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71.
Chen-Tong Hsu Yu-Tsan Lin Yao-Hsu Yang Bor-Luen Chiang 《Journal of microbiology, immunology, and infection》2004,37(2):121-123
Hyperimmunoglobulin E syndrome is a primary immunodeficiency disease characterized by markedly high titers of serum immunoglobulin E (IgE), chronic eczema, recurrent staphylococcal infections, pneumatoceles, reduced neutrophil chemotaxis, and variable impaired T cell function. There are no clinical tools for diagnosis and definitive laboratory investigation. Variability of presentation makes it easy to confuse the diagnosis with that of severe atopy or other rare immunodeficiencies. We report a case of a 6-year-old boy with hyperimmunoglobulin E syndrome with recurrent methicillin-resistant Staphylococcus aureus furunculosis. Physical examination revealed a peculiar facial appearance, pruritic dermatitis, and furunculosis over the scalp, neck, and back. Laboratory investigation revealed mild leukocytosis with eosinophilia, a very high immunoglobulin E level, defective neutrophil chemotaxis, and impaired lymphocyte proliferation to anti-CD3/CD28 monoclonal antibodies. The boy was discharged without incident after 2 weeks of antibiotic therapy and debridement. 相似文献
72.
Omalizumab in asthma 总被引:1,自引:0,他引:1
Omalizumab is a humanized mouse monoclonal antibody that binds specifically to the constant region of the immunoglobulin (Ig)E heavy chain. Omalizumab exerts its effects by reducing free serum IgE levels and FcepsilonRI expression on several cell types. These effects have been shown to result in decreased airway inflammation and clinical improvement. In multiple studies, omalizumab has been shown to be efficacious in the treatment of moderate-to-severe persistent asthma and is currently approved by the US Food and Drug Administration for the treatment of moderate-to-severe allergic asthma in patients age 12 yr and older. Moreover, omalizumab has been demonstrated to be effective in the treatment of children and adults with seasonal and perennial allergic rhinitis. Postmarketing surveillance has shown omalizumab to be a relatively safe and well-tolerated medication. 相似文献
73.
G Mirowski K F Austen L Chiang R F Horan A L Sheffer N Weidner G F Murphy 《Laboratory investigation; a journal of technical methods and pathology》1990,63(1):52-62
Biopsies of lesional and nonlesional skin from 14 patients with localized cutaneous or associated systemic mastocytosis were examined by ultrastructural and immunohistochemical techniques. Mast cells within lesions of the dermis were highly variable between patients with regard to cell number and extent of degranulation, although lesional sites consistently contained more mast cells than did nonlesional sites. Two mast cell patterns were identified based upon granule morphology. In biopsies from 8 patients, the majority of granules contained electron-dense amorphous zones; crystalline lattices; and indistinct, incomplete solid scrolls forming parallel lamellae. In biopsies from 6 patients, in addition to these granules, there were also granules composed of electron-dense amorphous zones, reticulated matrices, and/or distinct scrolls with lucent cores interrupted by dense spheres. The granule morphology for the first group (N = 8) was identical with that seen in the preponderant type of skin mast cell of 6 normal control subjects, whereas the granule morphology of the second group (N = 6) displayed an abnormal ultrastructural phenotype for skin that included granule types normally found not only in skin but also in intestinal lamina propria and lung. For individual patients, the patterns of granule ultrastructure were consistent between clinically nonlesional and lesional skin. A minority of cells in both patient groups appeared primitive ultrastructurally, exhibiting rudimentary, Golgi-associated progranules; monocyte-like morphologic characteristics; and mitotic activity. Moreover, when mast cells in lesional skin were screened for a limited panel of surface antigens, they displayed common patterns of reactivity (M718+, HLA-DR/DQ+, CD4+), and in a selected case, immunoelectron microscopy confirmed the presence of these antigens on mast cell plasma membranes. Dermal mast cells from normal donors (N = 6) lack these epitopes. These observations suggest that infiltrates in cutaneous mastocytosis may exhibit phenotypic characteristics not only of cutaneous mast cells, but in some patients also of mucosal mast cells. In either circumstance, the mast cells may display antigenic determinants common to monocyte/macrophages. Concordance of granule phenotype between lesional and clinically uninvolved skin of individual patients furthers the notion that even localized mastocytosis reflects covertly defective systemic mast cell homeostasis. 相似文献
74.
Tomac AC Grinberg A Huang SP Nosrat C Wang Y Borlongan C Lin SZ Chiang YH Olson L Westphal H Hoffer BJ 《Neuroscience》2000,95(4):1011-1023
Glial cell line-derived neurotrophic factor receptor alpha1 (GFRalpha1, also known as GDNFR-alpha) is a glycolipid-anchored membrane protein of the GFRalpha family, which binds glial cell line-derived neurotrophic factor [Jing S. et al. (1996) Cell 85, 1113-1124; Treanor J. J. et al. (1996) Nature 382, 80-83], a survival factor for several populations of central and peripheral neurons, including midbrain dopamine neurons [Lin L. F. et al. (1993) Science 260, 1130-1132], and mediates its ligand-induced cell response via a tyrosine kinase receptor called Ret [Takahashi M. et al. (1988) Oncogene 3, 571-578; Takahashi M. and Cooper G. M. (1987) Molec. Cell Biol. 7, 1378-1385]. In this paper, we show that mice with a null mutation of the GFRalpha1 gene manifest epithelial-mesenchymal interaction deficits in kidney and severe disturbances of intestinal tract development similar to those seen with glial cell line-derived neurotrophic factor or Ret null mutations. There is a marked renal dysgenesis or agenesis and the intrinsic enteric nervous system fails completely to develop. We also show that newborn GFRalpha1-deficient mice display no or minimal changes in dorsal root and sympathetic ganglia. This is in contrast to the deficits reported in these neuronal populations in glial cell line-derived neurotrophic factor and Ret null mutations. Mesencephalic dopaminergic neurons in the substantia nigra and ventral tegmental area appear intact at the time of birth of the mutated mice. Mice homozygous for the GFRalpha1 null mutation die within 24 h of birth because of uremia. Heterozygous animals, however, live to adulthood. There is a significantly reduced neuroprotective effect of glial cell line-derived neurotrophic factor in such heterozygous animals, compared with wild-type littermates, after cerebral ischemia. Taken together with previous data on glial cell line-derived neurotrophic factor and Ret, our results strongly suggest that GFRalpha1 is the essential GFRalpha receptor for signaling in the glial cell line-derived neurotrophic factor-Ret pathway in the kidney and enteric nervous system development, and that GFRalpha2 or GFRalpha3 cannot substitute for the absence of GFRalpha1. Moreover, neuroprotective actions of exogenous glial cell line-derived neurotrophic factor also require full GFRalpha1 receptor expression. 相似文献
75.
BACKGROUND: The skin of patients with atopic dermatitis (AD) exhibits a striking susceptibility to colonization and infection by Staphylococcus aureus. The exotoxins secreted by S. aureus can act as superantigens and classic allergens, inducing the production of functionally relevant specific IgE antibodies. The aim of this study was to compare the levels and positive rates of serum staphylococcal enterotoxin A (SEA)- and staphylococcal enterotoxin B (SEB)-specific IgE between atopic children with and without AD. METHODS: Sixty children with AD, 55 children with respiratory allergy without AD, and 24 nonatopic healthy children were studied. The levels and positive rates of serum SEA- and SEB-specific IgE were compared among three groups. The correlation between the levels or positive rates of serum SEA/SEB-specific IgE and the severity of AD or the presence of previous skin infections was studied. RESULTS: The children with AD had significantly higher levels and positive rates of serum SEA- and SEB-specific IgE than the atopic children without AD (P < 0.001) and the nonatopic children (P < 0.001). There was no significant difference in the levels and positive rates of serum SEA- and SEB-specific IgE between the atopic children without AD and the nonatopic children. With or without adjustment for the potential confounding effect of total serum IgE levels, the levels and positive rates of serum SEA- and SEB-specific IgE were significantly correlated with severity of AD (P <0.005), but they were not significantly different between AD children with and without previous skin infections. CONCLUSIONS: SEA and SEB may contribute to chronic inflammation and exacerbation of AD through the IgE-mediated immune response. 相似文献
76.
Chiao-Hsi Chiang Ronald D. Schoenwald 《Journal of pharmacokinetics and pharmacodynamics》1986,14(2):175-211
A single topical instillation of clonidine-3H HCl solution (0.2%) was administered to the rabbit eye (30 μl) in order to study the drug's ocular pharmacokinetics. Seven different tissues and plasma were excised and assayed for drug over 180min. By 45–60 min pseudoequilibrium is reached for the cornea, iris/ciliary body, and aqueous humor. Thereafter, drug levels in these tissues decline in parallel. The data are fit separately to a physiological model and a classical diffusion model for which seven ocular tissue compartments and a plasma reservoir are constructed for each model. Clearance terms and distribution equilibrium coefficients are determined from the tissue level data and used as parameters in fitting the mass balance differential equations representing the physiological model. The model parameters can also be fit to a 0.4% single dose. In a separate experiment, a topical infusion technique was designed to provide a constant rate input to the cornea until an apparent steady state was reached in aqueous humor at 55 min. Aqueous humor levels were assayed for clonidine over the infusion and postinfusion periods. The physiological model parameters are fit to the topical infusion data and show good agreement between the predicted and experimental data. The classical model is too complex to fit the data to integrated exponential equations primarily because the method of residuals is inadequate in determining a sufficient set of initial estimates. This is overcome by dividing the eight-compartment model into seven fragmental models, each representing one to five compartments. A stepwise procedure is developed in which initial estimates are obtained for each separate fragmental model and refined. The refined parameter values can then be used as initial estimates for the complex model. Differential equations for the complex model are fit simultaneously to tissue levels representing each compartment. By observation, the classical model fit the data more closely than the physiological model. Statistical moment theory is also applied to the topical infusion data to determine ocular pharmacokinetic parameters for clonidine. The calculated values are: corneal absorption rate constantk a , 0.00139 min?1; aqueous humor elimination rate constantk 10 , 0.0658min?1; mean residence timeMRT d , 35.6 min; apparent steadystate volume of distributionV ss, 0.530 ml; and ocular clearanceQ e , 14.9 =μl/min. The fraction absorbed from the single instillation is estimated as 0.0163. 相似文献
77.
Hsiang-Han Kao Hua-Shui Hsu Tai-Hsien Wu Hui-Fen Chiang Hui-Ying Huang Hui-Ju Wang Gloria Yang Wen-Yuan Lin 《Obesity research & clinical practice》2021,15(1):58-63
ObjectivesModerate-intensity exercise improves insulin sensitivity, which may depend on the intensity, duration, and frequency of exercise. We examined the effects of a single bout of short-duration high-intensity exercise (HIE) and long-duration lowintensity exercise (LIE) on insulin sensitivity and the adiponectin/leptin ratio in individuals with different body mass indices (BMIs) who do not exercise regularly.MethodsWe enrolled 42 healthy volunteers aged 20–64 years and divided them into two groups based on BMI: BMI <24 kg/m2 and BMI ≥27 kg/m2. They were randomly assigned to either the short-duration (20 min) HIE (70%–80% heart rate reserve, HRR) or long-duration (60 min) LIE training groups (30%–40% HRR). Glucose, insulin, adiponectin, and leptin levels were assessed before training and at 0, 30, 60, and 120 min after training.ResultsWe finally analyzed 27 normal weight and 9 obese individuals. No significant differences were observed in the baseline information of both BMI groups. Homeostatic model assessment for insulin resistance significantly improved for both exercise patterns in the normal weight group and for the HIE pattern in the obese group (P < 0.01), whereas the adiponectin/leptin ratio increased significantly only among normal weight participants with the LIE intervention.ConclusionBoth exercise patterns in BMI <24 kg/m2 and BMI ≥27 kg/m2 benefit on insulin resistance. Therefore, people can choose the way they can fit to improve insulin resistance both short-duration high-intensity exercise and long-duration low-intensity exercise. 相似文献
78.
Mohammad M. Obaidat James C. Graziano Maria Morales-Betoulle Shelley M. Brown Cheng-Feng Chiang John D. Klena 《Emerging infectious diseases》2021,27(2):653
The epidemiology of Rift Valley fever virus (RVFV) and Crimean-Congo hemorrhagic fever virus (CCHFV) in Jordan is unknown. Our investigation showed 3% of 989 tested dairy cattle, sheep, and goats were RVFV seropositive and 14% were CCHFV seropositive. Ongoing surveillance is needed to assess risk to humans and protect public health. 相似文献
79.
Vemulakonda Vijaya M. Sevick Carter Juarez-Colunga Elizabeth Chiang George Janzen Nicolette Saville Alison Adams Parker Beltran Gemma King Jordon Ewing Emily Kempe Allison 《International urology and nephrology》2021,53(8):1485-1495
International Urology and Nephrology - Studies based on administrative databases show that infant pyeloplasty is associated with minority race/ethnicity but lack clinical data that may influence... 相似文献
80.
As long as drug use and abuse persist in our society, a significant number of patients with various types of drug withdrawal will present to Emergency Departments. It is imperative that we recognize the signs and symptoms of drug withdrawal and render the appropriate treatments. Although it may be easy to recognize "skid row" alcoholics, a drug abuser with track marks on his (or her) arms or with a perforated nasal septum, the executive alcoholic, the elderly patient on chronic diazepam therapy, or the "blue collar" worker using cocaine may be more common and more elusive. Because most drug abusers use and can be dependent on multiple drugs, detoxification may need to proceed with one drug or one class of drugs at a time. Although our discussion has concentrated on the acute presentation and treatment of these symptoms for the emergency physician, we recognize that the acute treatment of withdrawal symptoms is only a small but vital part of withdrawal treatment. These patients will require chronic treatment, including social and psychologic counseling. As emergency physicians, by performing our jobs of recognition, stabilization, and counseling, we will fulfill the first critical link in the treatment of these patients. 相似文献