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111.
This study examines the immunomodulatory effect of a crude larval extract (CLE), obtained from first stage larvae (L1) of H. lineatum , and the purified fractions hypodermin A (HyA), HyB and HyC. Proliferative responses of peripheral blood mononuclear cells (PBMC) from uninfested and previously infested cattle and the production of the cytokines IL-10, IL-4 and IFN-γ, in response to concanavalin A (Con A), were determined. The stimulation index of peripheral blood mononuclear cells from uninfested cattle was significantly lower than that from infested animals with the different antigens assayed. The HyA was the antigen that most inhibited the proliferative response, followed by the HyB, the HyC and the CLE. This hypodermin provoked an increase of IFN-γ and a suppression of IL-10 production that would support a Th1-like cytokine response. The HyB reduced the production of IL-10 stimulated by the Con A in cultures from infested animals. The HyC did not modulate the production of cytokines. Finally, the CLE induced a marked suppression in the production of the different cytokines in cultures from naïve and previously sensitized animals. Our results indicate that Hypoderma larval secretions are comprised of different components (hypodermins) that individually induce distinct but partially overlapping modulatory responses.  相似文献   
112.
Disturbed grip function in women with rheumatoid arthritis.   总被引:2,自引:0,他引:2  
OBJECTIVE: Hand dysfunction is a frequent cause of disability in rheumatoid arthritis (RA). In patients with RA, we studied the precision grip-lift sequence in relation to pain, stiffness, and observer assessed hand function and their relation to patients' experience of clumsiness and tendency to drop objects. METHODS: Performance of the precision grip-lift sequence was studied in 23 women with RA and 7 age and sex matched controls. The results were correlated to self-estimation of pain and stiffness of hands and to observer assessed measurements of hand function. RESULTS: A prolongation of the preload and loading phases and of the acceleration part of the transition phase as well as a disturbance of the safety margin (SM) during precision grip-lift were noted. Patients with good hand function (low Grip Ability Test score; GAT) displayed normal or increased SM compared to the healthy controls, whereas patients with more pronounced disease exhibited a lower SM. Disturbances seen in the precision grip-lift performance were related to stiffness, range of motion, and GAT score. In RA patients with decreased hand function the SM was correlated to feeling of clumsiness, but did not explain the frequency of object dropping. CONCLUSION: A disturbance in the precision grip-lift performance was noted in patients with RA. These grip performance changes need further investigation to determine possible mechanisms.  相似文献   
113.
114.
Dexamethasone is a corticosteroid with proven efficacy for treating both anterior- and posterior-segment ocular diseases. Delivery of drugs to the back of the eye has always been a challenge, with dexamethasone being no exception. There are multiple delivery routes to the retina, with each exhibiting different pharmacokinetics, depending on the drug molecule and specific route of administration. In this study, we used intravenous (IV), subconjunctival (SC), and intravitreal (IVT) injections in rabbits to determine the pharmacokinetics of dexamethasone phosphate and its metabolic product, dexamethasone, at low (25 microg/kg) and high (250 microg/kg) doses. Plasma samples were collected from each group of animals at different time points up to 24 h after the injection. Using a liquid chromatographic mass spectrometric method with a limit of detection of 0.5 ng/mL, the plasma concentration for dexamethasone and its prodrug compound were quantified. IV delivery showed the fastest plasma elimination, followed by SC delivery. IVT delivery exhibited a depot effect, with very low plasma levels throughout the 24-h time course. At 24 h postinjection, only the high-dose IVT and low- and high-dose SC dexamethasone injections were still detectable in the plasma.  相似文献   
115.
116.
A predictive model for survival after in-hospital cardiopulmonary arrest   总被引:5,自引:0,他引:5  
BACKGROUND: In-hospital cardiopulmonary resuscitation (CPR) has seen a steady increase in the application of technology and techniques since the introduction of closed cardiac massage in 1960. Despite this progress, there has not been a demonstrated improvement in survival rates after in-hospital cardiac arrest over the last 40 years. Identification of prognostic factors associated with survival after a resuscitation attempt can help physician decisions and patients' end-of-life choices in a pre-arrest situation. METHODS: Using an Utstein-based template we analyzed 219 consecutive adult attempted resuscitations in a large urban teaching hospital over a 3-year period. The main outcome measures were survival to discharge, 1 and 3 months. Backwards stepwise logistic regression was used to select baseline variables that predict survival at discharge, 1 and 3 months. RESULTS: Survival rates at discharge, 1 and 3 months were 15.1, 13.3, and 11.5%. Meaningful neurological status (cerebral performance score of 1) at discharge was achieved in 61% of survivors. Independent predictors of survival were: higher body-mass index (BMI), presence of chronic renal insufficiency (CRI), respiratory arrest, ventricular tachycardia/fibrillation (VT/VF) as initial rhythm and arrest early during the hospital stay. A risk model based on these variables demonstrated a significant fit between predicted and observed survival at discharge with goodness of fit test P-value of 0.87. CONCLUSIONS: Survival after in-hospital cardiopulmonary arrest is poor and can be estimated by using clinical variables. If validated in a large prospective trial, this score could help physicians in attempting resuscitation, patients and families in making end-of-life decisions and hospitals in resource allocation.  相似文献   
117.
Inhibitors of nitric oxide synthase (NOS) have been reported to increase mean arterial pressure in animal models of sepsis and recently have been given to patients in septic shock. However, controlled studies to determine the effects of these agents on cardiovascular function and survival in awake animal models of sepsis have not been reported. To examine the therapeutic potential of NOS inhibition in septic shock, we challenged canines with endotoxin (2 or 4 mg/kg i.v.) and treated them with either normal saline or N omega-amino-L-arginine (10 or 1 mg/kg/h), the most specific inhibitor available for the isoform of NOS implicated in septic shock. Endotoxemic animals treated with N omega-amino-L-arginine (n = 11) had higher systemic and pulmonary vascular resistance indices (SVRI and PVRI, p less than or equal to 0.033) and decreased heart rates (p = 0.009), cardiac indices (CI, p = 0.01), oxygen delivery indices (p = 0.027), and oxygen consumption indices (p = 0.046) compared with controls (n = 6). Moreover, N omega-amino-L-arginine increased mortality rates after endotoxin challenge (10 of 11 vs. 1 of 6 controls, p = 0.005). Administration of L-arginine did not improve survival or alter the cardiopulmonary effects of N omega-amino-L-arginine, which suggests that inhibition of NOS may not have been competitive. In normal animals, N omega-amino-L-arginine alone (n = 3) increased SVRI (p = 0.0008) and mean arterial pressure (p = 0.016), and decreased CI (p = 0.01) compared with saline-treated controls (n = 3), but, at the high dose, also produced neuromuscular rigidity and seizure-like activity that was not apparent in the endotoxemic model. Thus, the mortality rate from endotoxemia increased either because of NOS inhibition per se or because of properties unique to N omega-amino-L-arginine, or both.  相似文献   
118.
The purpose of the study was to compare a heel stick conducted during Kangaroo Care (skin-to-skin contact) with the mother to a heel stick in a warmer in reducing premature infant physiologic and behavioral pain responses. Twenty-four premature infants in a university-based neonatal intensive care unit were recruited and randomized to 2 sequences: sequence A group received 3 hours of Kangaroo Care (with a heel stick in Kangaroo Care) followed by 3 hours in a warmer (with a heel stick in the warmer). Sequence B group had warmer care and a heel stick (in the warmer) before Kangaroo Care and a heel stick (in Kangaroo Care). Heart rate, respiratory rate, oxygen saturation, crying time, and behavioral state were measured before, during, and after heel stick. Repeated measures ANOVA and Mann Whitney U statistics were performed. Heart rate and length of crying in response to pain were significantly reduced during Kangaroo Care and the Kangaroo Care heel stick as compared to when infants were in the warmer and had a heel stick in the warmer. Three infants did not cry at all during the Kangaroo Care heel stick; infants slept more during Kangaroo Care than in the warmer. Kangaroo Care positioning before and during heel stick is a simple and inexpensive analgesic intervention to ameliorate pain in stable premature infants.  相似文献   
119.

Background

A novel subcutaneous allergen immunotherapy formulation (gpASIT+?) containing Lolium perenne peptides (LPP) and having a short up‐dosing phase has been developed to treat grass pollen–induced seasonal allergic rhinoconjunctivitis. We investigated peptide immunotherapy containing the hydrolysate from perennial ryegrass allergens for the optimum dose in terms of clinical efficacy, immunogenicity and safety.

Methods

This prospective, double‐blind, placebo‐controlled, phase IIb, parallel, four‐arm, dose‐finding study randomized 198 grass pollen–allergic adults to receive placebo or cumulative doses of 70, 170 or 370 μg LPP. All patients received weekly subcutaneous injections, with the active treatment groups reaching assigned doses within 2, 3 and 4 weeks, respectively. Efficacy was assessed by comparing conjunctival provocation test (CPT) reactions at baseline, after 4 weeks and after completion. Grass pollen–specific immunoglobulins were analysed before and after treatment.

Results

Conjunctival provocation test (CPT) response thresholds improved from baseline to V7 by at least one concentration step in 51.2% (170 μg; P = .023), 46.3% (370 μg), and 38.6% (70 μg) of patients receiving LPP vs 25.6% of patients receiving placebo (modified per‐protocol set). Also, 39% of patients in the 170‐μg group became nonreactive to CPT vs 18% in the placebo group. Facilitated allergen‐binding assays revealed a highly significant (P < .001) dose‐dependent reduction in IgE allergen binding across all treatment groups (70 μg: 17.1%; 170 μg: 18.8%; 370 μg: 26.4%). Specific IgG4 levels increased to 1.6‐fold (70 μg), 3.1‐fold (170 μg) and 3.9‐fold (370 μg) (mPP).

Conclusion

Three‐week immunotherapy with 170 μg LPP reduced CPT reactivity significantly and increased protective specific antibodies.
  相似文献   
120.

Background

Systemic allergic reactions are a risk for allergen immunotherapy that utilizes intact allergen preparations. We evaluated the safety, efficacy and immune mechanisms of short‐course treatment with adjuvant‐free Lolium perenne peptides (LPP) following a 6‐week dose‐escalation protocol.

Methods

In a prospective, dose‐escalation study, 61 grass pollen–allergic patients received 2 subcutaneous injections of LPP once weekly for 6 weeks. Safety was assessed evaluating local reactions, systemic reactions and adverse events. The clinical effect of LPP was determined by reactivity to the conjunctival provocation test (CPT). Specific IgE, IgG4 and blocking antibodies were measured at baseline (V1), during (V6) and after treatment (V8).

Results

No fatality, serious adverse event or epinephrine use was reported. Mean wheal diameters after injections were <0.6 cm and mean redness diameters <2.5 cm, independent of dose. Transient and mostly mild adverse events were reported in 33 patients. Two patients experienced a grade I and 4 patients a grade II reaction (AWMF classification). At V8, 69.8% of patients became nonreactive to CPT. sIgG4 levels were higher at V6 (8.1‐fold, < .001) and V8 (12.2‐fold, < .001) than at V1. The sIgE:sIgG4 ratio decreased at V6 (?54.6%, < .001) and V8 (?71.6%, < .001) compared to V1. The absolute decrease in IgE‐facilitated allergen binding was 18% (< .001) at V6 and 25% (< .001) at V8.

Conclusion

Increasing doses of subcutaneous LPP appeared safe, substantially diminished reactivity to CPT and induced blocking antibodies as early as 4 weeks after treatment initiation. The benefit/risk balance of LPP immunotherapy remains to be further evaluated in large studies.
  相似文献   
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