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1.
Exp Eye Res ; 82(5): 753-9, 2006 May.
Article in English | MEDLINE | ID: mdl-16289049

ABSTRACT

Glaucoma, one of the leading causes of blindness, is associated with high intraocular pressure (IOP) as a risk factor. The aim of this study was to examine both local and systemic effects of chronic topical administration of the synthetic CB1/CB2 agonist, WIN-55-212-2 and its potential to sustain ocular hypotension. WIN-55-212-2 (0.5%) or Tocrisolve, the vehicle, was administered topically three times daily to rats with surgically created glaucoma for 4 weeks, followed by a 1-week washout period. IOP, blood pressure and heart rate were measured weekly along with confocal microscopy and slit lamp biomicroscopy to detect ocular toxicity. IOP decreased rapidly by up to 47% in the WIN-55-212-2 treated group from 14.1+/-0.7 to 6.6+/-0.2 mmHg. The decrease was maintained during the treatment period. After the washout period, IOP (12.3+/-0.2 mmHg) was not different from baseline. In the contralateral eye, IOP showed a downward trend. Tocrisolve alone had no effect on IOP. No changes in blood pressure, heart rate or indicators of ocular toxicity were noted within either group. Topical application of WIN-55-212-2 significantly deceased IOP for duration of treatment. The decrease was sustained without the development of tolerance. Following cessation of therapy, IOP rapidly returned to baseline. No significant cardiovascular effects or ocular toxicity were noted during chronic topical therapy with either drug or vehicle.


Subject(s)
Antihypertensive Agents/therapeutic use , Glaucoma/drug therapy , Morpholines/therapeutic use , Naphthalenes/therapeutic use , Animals , Antihypertensive Agents/adverse effects , Benzoxazines , Blood Pressure/drug effects , Cornea/drug effects , Cornea/pathology , Drug Administration Schedule , Glaucoma/physiopathology , Heart Rate/drug effects , Male , Microscopy, Confocal , Morpholines/adverse effects , Naphthalenes/adverse effects , Ophthalmic Solutions , Rats , Rats, Sprague-Dawley
2.
J Ocul Pharmacol Ther ; 20(6): 533-47, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15684812

ABSTRACT

This study objectively compares efficacy of dexamethasone Na phosphate 0.1%, fluorometholone 0.1% (FML), loteprednol etabonate 0.5% (Lotemax [LE]; Bausch & Lomb Pharmaceuticals, Inc., Tampa, FL), prednisolone acetate 1% (Pred Forte [PRED F]; Allergan Pharmaceuticals, Irvine, CA), and generic prednisolone acetate 1% (PRED A). These steroids were administered for 24 hours or 72 hours to New Zealand white rabbits with endotoxin-induced uveitis. Intraocular pressure (IOP), slit-lamp examination, and confocal microscopy were performed daily. Internalization of the glucocorticoid receptor (GC) was assayed in iris tissue by Western blot, and protein in aqueous humor by Bradford assay. Only LE and PRED F treatments significantly internalized GC receptor after 72 hours of treatment. Only LE and PRED A reduced protein concentration between 24 hours and 72 hours of treatment. All drugs improved clinical signs after 24 hours of treatment. None of the steroids promoted return of the inflammation-induced corneal thickness to baseline. While none returned IOP to baseline, LE was most effective. Confocal microscopy indicated that only treatment with LE reverted the abnormal endothelial-cell shape to normal. In conclusion, all steroid treatments reduced uveitis to some degree but LE was consistently effective. A longer observation period may be required to document the return of IOP and corneal thickness to baseline values.


Subject(s)
Glucocorticoids/therapeutic use , Uveitis, Anterior/drug therapy , Acute Disease , Administration, Topical , Androstadienes/administration & dosage , Androstadienes/therapeutic use , Animals , Aqueous Humor/chemistry , Aqueous Humor/drug effects , Blotting, Western , Conjunctiva/blood supply , Conjunctiva/physiopathology , Corneal Stroma/chemistry , Corneal Stroma/drug effects , Corneal Stroma/pathology , Dexamethasone/administration & dosage , Dexamethasone/analogs & derivatives , Dexamethasone/therapeutic use , Endothelium, Corneal/drug effects , Endothelium, Corneal/pathology , Endothelium, Corneal/physiopathology , Eye Proteins/analysis , Fibrin/analysis , Fluorometholone/administration & dosage , Fluorometholone/therapeutic use , Glucocorticoids/administration & dosage , Intraocular Pressure/drug effects , Lipopolysaccharides/administration & dosage , Lipopolysaccharides/toxicity , Loteprednol Etabonate , Male , Particle Size , Prednisolone/administration & dosage , Prednisolone/analogs & derivatives , Prednisolone/therapeutic use , Rabbits , Receptors, Glucocorticoid/metabolism , Suspensions , Time Factors , Uveitis, Anterior/chemically induced , Uveitis, Anterior/metabolism , Vitreous Body/chemistry , Vitreous Body/drug effects , Vitreous Body/pathology
3.
Ann Allergy Asthma Immunol ; 86(4): 373-81, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11345278

ABSTRACT

BACKGROUND: Accurate and reliable evaluation of the presence or absence of allergen-specific IgE is important in the differential diagnosis of allergic disease. A variety of different commercial tests are available for this purpose. There are few data available to judge how the results of these different tests compare with one another in everyday use. OBJECTIVE: To examine prospectively the extent of comparability among specific IgE results from different laboratories. METHODS: Six diagnostic laboratories employing five different methods to assay specific IgE were selected. Aliquots from 26 serum samples that contained variable levels of IgE specific to 17 common aeroallergens were sent in triplicate to each study laboratory during a 6-week time period. Results were reported numerically and by class scores and then compared by examining their concordance using Kendall's W nonparametric statistical test. In addition, cut-off values were compared by a best agreement analysis using reported results. Reproducibility was determined using precision profiles based upon the coefficient of variation among triplicates for each allergen across the range of reported results. RESULTS: In all, 7,813 tests were analyzed. Concordance among different assays in commercial use with one exception was not good. This was particularly true around the cut-off region where most assays demonstrated high imprecision. The Pharmacia CAP System used by two different laboratories demonstrated highly comparable results with good precision. Some assays were reproducible but not accurate. Others were neither reproducible nor accurate. CONCLUSIONS: The results of this study indicate that not all commercial laboratories/assays for specific IgE provide reproducible and accurate data. Significant potential for misdiagnosis was detected for some reported results. Methods were identified that do give sensitive, accurate, and reproducible results.


Subject(s)
Diagnostic Errors , Hypersensitivity, Immediate/diagnosis , Immunoglobulin E/analysis , Radioallergosorbent Test/standards , Allergens/immunology , False Negative Reactions , False Positive Reactions , Humans , Hypersensitivity, Immediate/immunology , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity
4.
Ann Allergy Asthma Immunol ; 86(2): 196-202, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11258690

ABSTRACT

BACKGROUND: UniCAP Phadiatop is a single laboratory test designed to determine the presence or absence of specific IgE to a variety of common inhalants. Its purpose is to aid in the differentiation of patients with symptoms attributable to allergic disease from other common causes. METHODS: Consecutive children and adolescent patients (n = 145) at two centers were examined by having their history and physical examination performed by two board certified allergists. Their conclusions along with skin prick tests and specific IgE measurements regarding seven common inhalants (mite, oak, ragweed, grass, dog, cat, Alternaria) were compared with UniCAP Phadiatop test results. This was done using concordance of all test results. Attempts to resolve test discrepancies, when found, included specific RAST inhibitions, total IgE values, and physicians' judgment after testing. RESULTS: All patients with resolved diagnoses (143 of 145, 103 positive and 40 negative) were identified correctly by the UniCAP Phadiatop test. Skin test results and specific IgE measurements correlated well, but neither correlated well with the history by itself, suggesting a minimal false-positive component of the history of 23%. UniCAP Phadiatop results demonstrated a quantitative relationship between the patient's score and the amount of IgE specific to these individual allergens. CONCLUSIONS: The UniCAP Phadiatop test was shown to be highly sensitive and specific in differentiating individuals who are sensitized to common inhalants from those who are not. This test is recommended to all physicians as an aid in diagnostic and referral decisions for patients suspected of having an inhalant allergic diathesis.


Subject(s)
Allergens/administration & dosage , Diagnostic Tests, Routine/standards , Administration, Inhalation , Adolescent , Allergens/immunology , Antibodies, Anti-Idiotypic/blood , Antibodies, Anti-Idiotypic/immunology , Antibody Specificity , Asthma/diagnosis , Child , Conjunctivitis/diagnosis , Diagnostic Tests, Routine/methods , Female , Humans , Immunization , Immunoglobulin E/blood , Male , Medical History Taking , Physical Examination , Rhinitis/diagnosis , Skin Tests
5.
J Clin Pharmacol ; 41(12): 1259-70, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11762553

ABSTRACT

Development of problem-solving skills is vital to professional education as is factual recall. Student mastery must be measured to document student achievement requiredfor completion of educational requirements and professional certification. These measurements also help determine if the educational process is meeting its goal of helping students develop critical cognitive skills for therapeutic problem solving. Testing student growth in the ability to solve problems is less understood. Stressing integration of information across disciplines to derive answers is also important. Test items should resemble the real-world task that students are expected to master. Thatisreallythe essence of content validity, which means faculty should be biased toward presenting information that way. This article is based on a symposium presented at the annual meeting of the American College of Clinical Pharmacology in September 1996. Symposium goals were to define purposes and uses of student evaluations by type and format, including application of techniques that improve evaluation, precision, and validity. Technical applications of computer-based learning and evaluation of problem-solving skills are described. Actual experience with evaluation of problem solving in the curriculum is discussed. The process by which a medical school developed and implemented an evaluation system for a new problem-based curriculum is presented, followed by a critique of the successes and problems encountered during the first year of implementation. Criteria that a well-constructed evaluation program must meet are explored. The approach and philosophy of national standardized testing centers are explained.


Subject(s)
Educational Status , Pharmacology, Clinical/education , Problem-Based Learning , Reproducibility of Results , Software , Teaching
6.
Public Health ; 115(6): 387-93, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11781848

ABSTRACT

Disparities in health and medical conditions among ethnic and racial groups have been repeatedly documented. These inequalities, which have been noted in the recent past, include health outcomes such as quality of life and mortality, process, accessibility and appropriateness of care, and the prevalence of certain degenerative conditions and infectious diseases. Syphilis, a sexually transmitted disease (STD) which seemed to have disappeared or had been controlled over the years, has now re-emerged as a major public health problem in many rural, urban and suburban communities. Progression of the current rate of syphilis, which erupted in Baltimore during the later part of 1994, has continued unabated, most especially among the ethnic minorities, despite efforts of the Baltimore City Health Department and Maryland Department of Health and Mental Hygiene to control the epidemic. With the current incidence rates of 270 per 100 000 live births for congenital syphilis and 99.3 per 100 000 population for primary, secondary and latent syphilis (96% of the cases being in the non-white population), Baltimore becomes the city with the highest number of syphilis cases in the nation, surpassing the national average of 2.6 cases per 100 000 population. This study, which utilizes a combination of retrospective and questionnaire-oriented approach, was designed to assess factors that influenced the high incidence of syphilis among Baltimore inner-city dwellers between 1994 and 1998. Data for the study included syphilis reports from private physicians, the Baltimore City Health Department, STD clinics, the Center for Disease Control (CDC), and ethnographic interviews. Factors favoring the distribution and infectivity of the disease among the inner-city dwellers include greater poverty, high level of communication gaps between providers and a cross-section of minority inner-city dwellers, exchange of sex for crack cocaine, lower educational background, and inadequate and inappropriate health education/health promotion programs for the ethnic minorities.The paper calls for, among other things, culturally-sensitive and competent syphilis elimination/prevention health education and health promotion programs for the ethnic minority inner-city dwellers of Baltimore.


Subject(s)
Minority Groups/statistics & numerical data , Syphilis/ethnology , Urban Health/statistics & numerical data , Adolescent , Adult , Baltimore/epidemiology , Female , Humans , Male , Middle Aged , Prevalence , Risk Factors , Socioeconomic Factors , Surveys and Questionnaires , Syphilis/transmission
7.
J Clin Pharmacol ; 40(9): 990-1006, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10975070

ABSTRACT

Nineteenth century ophthalmology, characterized by significant gains in diagnostic techniques, provided the basis for great advancements in treatment during the 20th century. Drug therapy at the turn of the century was empiric, palliative, and often toxic. The development of ocular pharmacology during the 20th century provided the basis for a rational therapeutic approach to ocular disease. Foremost among the therapeutic developments were antibiotics, due to their potential to cure conditions that frequently resulted in blindness. Second, other therapeutic classes provided palliative therapy for chronic diseases, and thus decreased morbidity. For example, drugs specifically targeting many different aspects of glaucoma have had remarkable success controlling intraocular pressure and forestalling development of blindness. In addition, other new approaches provided palliative therapy for nonblinding conditions and effective adjuncts to surgical procedures. Antiallergy and anti-inflammatory drugs greatly increased patient comfort and facilitated treatment of allergic and inflammatory reactions. Local anesthetics and analgesia reduced patient discomfort during surgery. Other adjunct drugs improved surgical outcomes by reducing inflammation and infectious complications. The 21st century will undoubtedly provide novel approaches to address many of today's therapeutic dilemmas. Photodynamic therapy, growth factors, antisense technology, and genetic-based therapies all show great promise. Many of the conditions that are only treated palliatively today will be curable in the next century using many of these pharmacological advances.


Subject(s)
Eye Diseases/therapy , Ophthalmology/history , Anti-Allergic Agents/therapeutic use , Anti-Infective Agents/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Blindness/etiology , Blindness/prevention & control , Eye Diseases/complications , Eye Diseases/drug therapy , Eye Diseases/surgery , Glaucoma/etiology , Glaucoma/surgery , History, 20th Century , Humans , Mydriatics/administration & dosage , Mydriatics/therapeutic use , Ophthalmology/trends , Palliative Care
8.
J Allergy Clin Immunol ; 105(6 Pt 1): 1077-84, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10856139

ABSTRACT

During the past several years, immunoassays for specific IgE antibodies have been refined to permit reporting results in mass units. Thus quantitative immunoassays for IgE antibodies may be an adjunct to skin tests. In cases of food allergy among children with atopic dermatitis, cutoff values for IgE antibody concentrations to egg, milk, peanut, and fish have been derived to provide 95% positive and 90% negative predictive values. Food-specific IgE antibody determinations can also be used to predict which food allergies are resolving spontaneously. Elevated egg-specific IgE antibody levels in infancy are associated with significantly increased risk for development of inhalant allergies later in childhood. In cases of inhalant allergy, specific IgE antibody levels correlate closely with results of inhalation challenge studies in cat-sensitive persons. Also, mite-specific IgE antibody levels correlate significantly with the mite allergen contents of reservoir dust in the homes of mite-sensitive persons. Immunoassays for quantitation of specific IgE antibodies may be used to document allergen sensitization over time and to evaluate the risk of reaction on allergen exposure. However, immunoassays and skin tests are not entirely interchangeable, and neither will replace the other in appropriate circumstances.


Subject(s)
Antibodies, Anti-Idiotypic/blood , Hypersensitivity/blood , Child, Preschool , Food Hypersensitivity/blood , Humans , Immunoassay , Immunoglobulin E/immunology , Infant
9.
J Allergy Clin Immunol ; 105(6 Pt 1): 1221-30, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10856158

ABSTRACT

BACKGROUND: Different laboratory assays are used to detect and measure specific IgE antibodies. No standard exists to assess their analytic performance. OBJECTIVE: We sought to analyze reported specific IgE results from different laboratories on the same serum samples for their accuracy and precision. METHODS: Blinded serum samples (26) containing variable levels of specific IgE to 17 common aeroallergens were sent on 3 different occasions through normal channels to 6 laboratories that used 5 different test procedures. Six samples were presented as a dilution series. Laboratory-assay performance was assessed by analyzing the reported results (n = 12, 708) by using ordinary least squares regression with slope coefficients, the t statistic, SEs, confidence intervals, and R (2) values. These were compared with a theoretic ideal assay as the reference. RESULTS: Analysis revealed that one system used in two different laboratories performed nearly as well as the ideal standard, with an overall average slope (0.97; range, 0.91-1.01), SE (0.05; range, 0.02-0.16), R (2) value (93%; range, 0.64-0.99), and coefficient of variation (10.3%; range, 6%-14%). Extensive variability was observed in the other 4 laboratory-assay systems with respect to overall average slope (0.76; range, 0.11-1.24), SE (0.19; range, 0.03-0.95), R (2) value (53%; range, 0.00-0.98), and coefficient of variation (19%; range, 5%-49%). For some specific allergens, some laboratories-assays were not able to detect serial dilutions of the same sample. CONCLUSIONS: One commercial system used in two different laboratories performed nearly as well as the ideal standard. Four of the laboratories-assays for specific IgE antibodies demonstrated substandard overall performance with multiple instances of poor precision and accuracy, particularly for certain allergens, such as weeds and molds.


Subject(s)
Air Pollutants/analysis , Air Pollution/analysis , Allergens/immunology , Antibodies, Anti-Idiotypic/blood , Air Pollutants/standards , Antibody Specificity , Antigens, Fungal/analysis , Diagnostic Tests, Routine/standards , Epitopes , Humans , Immunoassay/standards , Immunoglobulin E/immunology , Reference Standards , Reproducibility of Results
10.
Proteins ; 38(3): 341-9, 2000 Feb 15.
Article in English | MEDLINE | ID: mdl-10713993

ABSTRACT

The 2 S seed storage protein, sunflower albumin 8, contains an unusually high proportion of hydrophobic residues including 16 methionines in a mature protein of 103 amino acids. A structural model, based on the known structure of a related protein, has been constructed as a four-helix bundle cross-linked by four disulphide bonds. This model structure is consistent with data from circular dichroism and nuclear magnetic resonance experiments. Analysis of the model's surface shows the presence of a large hydrophobic face that may be responsible for the highly stable emulsions this protein is known to form with oil/water mixtures.


Subject(s)
Plant Proteins/chemistry , 2S Albumins, Plant , Amino Acid Sequence , Antigens, Plant , Circular Dichroism , Helianthus/chemistry , Magnetic Resonance Spectroscopy , Mass Spectrometry , Methionine/chemistry , Models, Molecular , Molecular Sequence Data , Plant Proteins/isolation & purification , Protein Structure, Quaternary , Protein Structure, Secondary , Seeds/chemistry , Sequence Alignment , Ultracentrifugation
11.
Ann Allergy Asthma Immunol ; 84(2): 193-6, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10719776

ABSTRACT

PURPOSE: To compare the diagnostic value of two commercial in vitro tests for the detection of latex-specific IgE antibodies. METHODS: Serum samples were collected from latex-allergic and nonlatex-allergic individuals. Persons were classified as latex allergic if they had a positive clinical history and a positive skin prick test with a latex extract. Persons with no latex-related symptoms and negative skin tests were classified as nonlatex allergic. The serum samples were tested in a blinded fashion by a laboratory using the CAP (Pharmacia-Upjohn) and AlaSTAT (Diagnostic Products Company) assays. Values of 0.35 kA U/L or greater were considered positive in both tests. RESULTS: The 143 sera studied came from 83-latex allergic and 60 nonallergic persons. The in vitro tests were found to have sensitivities of 79.5% and 73.8%, and specificities of 90.2% and 91.7%, for CAP and AlaSTAT, respectively. The positive predictive values were 91.7% and 92.5%, while the negative predictive values were 76.4% and 71.4% for the CAP and AlaSTAT, respectively. CONCLUSION: In individuals classified by the combination of clinical history and skin test results, both the Pharmacia CAP and the DPC AlaSTAT demonstrated acceptable sensitivities, specificities, and predictive values for detection of antilatex IgE antibodies. These findings suggest that both assays can be useful adjuncts to the diagnosis of latex allergy.


Subject(s)
Latex Hypersensitivity/blood , Skin Tests/instrumentation , Adolescent , Adult , Antibodies, Anti-Idiotypic/blood , Child , Child, Preschool , Female , Humans , Immunoglobulin E/immunology , Infant , Male , Middle Aged , Predictive Value of Tests , Skin Tests/methods
13.
J Biol Chem ; 274(38): 26828-37, 1999 Sep 17.
Article in English | MEDLINE | ID: mdl-10480890

ABSTRACT

The 2 S seed storage protein, sunflower albumin 8 (SFA-8), contains an unusually high proportion of hydrophobic residues including 16 methionines (some of which may form a surface hydrophobic patch) in a disulfide cross-linked, alpha-helical structure. Circular dichroism and fluorescence spectroscopy show that SFA-8 is highly stable to denaturation by heating or chaotropic agents, the latter resulting in a reversible two-state unfolding transition. The small m(U) (-4.7 M(-1) at 10 degrees C) and DeltaC(p) (-0.95 kcal mol(-1) K(-1)) values indicate that relatively little nonpolar surface of the protein is exposed during unfolding. Commensurate with the unusual distribution of hydrophobic residues, stopped-flow fluorescence data show that the folding pathway of SFA-8 is highly atypical, in that the initial product of the rapid collapse phase of folding is a compact nonnative state (or collection of nonnative states) that must unfold before acquiring the native conformation. The inhibited folding reaction of SFA-8, in which the misfolded state (m(M) = -0.95 M(-1) at 10 degrees C) is more compact than the transition state for folding (m(T) = -2.5 M(-1) at 10 degrees C), provides direct kinetic evidence for the transient misfolding of a protein.


Subject(s)
Plant Proteins/chemistry , Protein Folding , 2S Albumins, Plant , Antigens, Plant , Helianthus , Kinetics , Models, Chemical , Protein Denaturation , Seeds/chemistry
14.
Curr Eye Res ; 18(2): 150-7, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10223660

ABSTRACT

PURPOSE: After corneal injury, persistent epithelial defects (PED's) may occur due to the chronic failure of the regenerating epithelium to adhere to the underlying stroma. The aim of this study was to examine the potential of epsilonaminocaproic acid (EACA) as a topical treatment for PED's. EACA inhibits the activation of plasmin, which metabolizes fibronectin. Fibronectin, a glycoprotein, anchors corneal epithelium to the basement membrane and the underlying stroma. METHODS: In anesthetized rabbits, PED's were induced with sodium hydroxide (1 N). Seven days later, during the late healing phase, treatment began with administration of EACA (30%) to the right eye and administration of vehicle alone to the left eye three times daily. A control group received neither EACA nor vehicle. Rabbits were treated for 19 days. PED's were visualized by fluorescein staining. Their size was mapped using digital planimetry. RESULTS: After 11 days of treatment with EACA, treated PED's were 50% smaller than in corneas treated with vehicle alone. Following treatment for 15 days, corneas treated with EACA had significantly greater re-epithelialization than vehicle-treated or control corneas. Frozen sections stained immunofluorescently for fibronectin appeared to qualitatively contain more adherent fibronectin in treated corneas. Transmission and scanning electron microscopy indicated that the epithelium was more polymorphic, thinner and vacuolated in untreated controls compared to EACA treated eyes. Light microscopy demonstrated more continuous adherent epithelium after EACA treatment. CONCLUSIONS: Topically administered EACA decreases both the severity and incidence of persistent epithelial defects produced by alkali bums to the cornea. EACA appears to promote adherence of the regenerating epithelium to the underlying stroma. Thus, topically administered EACA may be an effective treatment for this chronic condition.


Subject(s)
Aminocaproic Acid/therapeutic use , Antifibrinolytic Agents/therapeutic use , Corneal Diseases/drug therapy , Epithelium, Corneal/physiology , Regeneration/drug effects , Wound Healing/drug effects , Administration, Topical , Aminocaproic Acid/administration & dosage , Animals , Antifibrinolytic Agents/administration & dosage , Burns, Chemical/drug therapy , Burns, Chemical/metabolism , Burns, Chemical/pathology , Cell Adhesion/drug effects , Corneal Diseases/metabolism , Corneal Diseases/pathology , Epithelium, Corneal/metabolism , Epithelium, Corneal/ultrastructure , Eye Burns/chemically induced , Eye Burns/metabolism , Eye Burns/pathology , Female , Fibronectins/metabolism , Fluorescent Antibody Technique, Indirect , Microscopy, Fluorescence , Rabbits , Sodium Hydroxide
16.
Can J Ophthalmol ; 33(6): 308-13, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9818127

ABSTRACT

BACKGROUND: Tranexamic acid has been shown to greatly reduce the incidence of secondary hemorrhage when administered orally or intravenously. Topical administration of the drug should result in much lower serum concentrations, with fewer adverse effects. We performed a study to determine whether topical application of tranexamic acid would yield higher intraocular concentrations and lower serum concentrations of drug than intravenous administration. METHODS: Ten New Zealand white rabbits received 25 mg/kg of tranexamic acid intravenously every 8 hours for 3 days. Another group of 10 rabbits received one drop (0.05 mL) of commercially available tranexamic acid solution (100 mg/mL) every 8 hours for 3 days to one eye. Tranexamic acid levels in the aqueous humour, vitreous humour and serum 1 hour after administration of the last dose of drug were determined. RESULTS: Analysis of variance showed that aqueous concentrations of tranexamic acid were significantly higher with topical delivery than with intravenous administration (15 vs. 9 micrograms/mL)(p < 0.05). Serum concentrations were significantly lower following topical administration (9 vs. 19 micrograms/mL)(p < 0.01). The drug was not detected in the vitreous humour in either group. INTERPRETATION: Topical delivery of tranexamic acid may prove to be valuable in yielding therapeutic intraocular concentrations of drug in patients with hyphema while minimizing systemic toxicity.


Subject(s)
Antifibrinolytic Agents/pharmacokinetics , Aqueous Humor/metabolism , Tranexamic Acid/pharmacokinetics , Vitreous Body/metabolism , Administration, Topical , Animals , Antifibrinolytic Agents/administration & dosage , Chromatography, High Pressure Liquid , Follow-Up Studies , Injections, Intravenous , Pilot Projects , Rabbits , Therapeutic Equivalency , Tissue Distribution , Tranexamic Acid/administration & dosage
17.
J Ocul Pharmacol Ther ; 14(2): 109-18, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9572536

ABSTRACT

Antifibrinolytic agents, epsilon-aminocaproic acid (EACA) and tranexamic acid (TXA), have been reported to be efficacious in the treatment of chronic persistent epithelial defects. Within the regulatory mechanism of corneal reepithelialization, fibronectin serves as a primary adhesive component in the healing process and anchors regenerating epithelial cells to underlying stroma. EACA and TXA inhibit the activation of plasmin thereby decreasing plasmin-induced catabolism of fibronectin. In this study, acute reepithelialization following treatment with EACA and TXA was evaluated in the cultured rat cornea model. Sprague Dawley rat corneal explants with 3 mm corneal defects, induced with 1 N NaOH, were cultured with either EACA or TXA. After 12 or 24 hr incubation periods, corneal explants were stained with bromodeoxyuridine stain for measuring cellular division and migration or Trypan Blue for measuring the extent of dead cells. Both EACA and TXA increased the rate of reepithelialization in comparison to an untreated control. EACA was up to 35% more efficacious than TXA. Thus, this study demonstrated an acute effect for EACA and TXA versus the previously reported efficacy of chronic therapy required for persistent epithelial defects. Broad applications may prove beneficial in the clinical treatment of corneal abrasions, persistent corneal epithelial defects, or alkali burns.


Subject(s)
Aminocaproic Acid/pharmacology , Antifibrinolytic Agents/pharmacology , Epithelium, Corneal/drug effects , Epithelium, Corneal/physiology , Regeneration/drug effects , Tranexamic Acid/pharmacology , Animals , Cell Division/drug effects , Coloring Agents , Culture Techniques , Epithelium, Corneal/cytology , Female , Rats , Rats, Sprague-Dawley , Trypan Blue
18.
Ann Allergy Asthma Immunol ; 79(4): 303-10, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9357374

ABSTRACT

BACKGROUND: Endotoxin is an inflammatory made by gram negative bacteria that can irritate the skin, induce respiratory problems, fever, and shock. It is an adjuvant for both delayed hypersensitivity and IgE production and has been shown to magnify antigen specific mediator release. Since many of the clinical problems associated with natural latex products involve similar clinical sequelae, we investigated the possibility that latex gloves might be contaminated with endotoxin. OBJECTIVE: To measure the endotoxin content of a variety of natural latex gloves, investigate the its distribution and origin, associated with latex proteins, and determine the particle sizes associated with its release. METHODS: Endotoxin, protein, and allergen were measured using a quantitative kinetic Limulus assay, modified Lowry, and RAST inhibition, respectively. Particle size and density were determined using an Anderson multistage air sampler and CsCl2 gradient. RESULTS: Endotoxin was found to be a highly significant contaminant of some latex gloves. Levels ranged from 0.09 ng to 2.8 micrograms/g of glove. Protein levels ranged from < 25 to 1150 micrograms/g of glove while allergen levels ranged from < 1 to 837 micrograms/g of glove. Endotoxin and protein eluted rapidly from the interior of the gloves tested. Greater than 70% of the endotoxin was found to be associated with particles in the < 7 microns aerodynamic diameter range. The highest levels of endotoxin were found in nonsterile examination gloves with a tendency towards powdered gloves containing more endotoxin and protein. A slurry containing cross-linked dextran through which gloves were dipped revealed very high endotoxin contamination (64 micrograms/mL) while unused cross-linked dextran has very little associated endotoxin. CONCLUSIONS: These data demonstrate that some natural rubber latex gloves, particularly nonsterile examination gloves, are contaminated with high amounts of endotoxin and proteins. These were found mostly on the inside of gloves and were released as very small respirable particles that were not physically associated with the powder. These findings support the hypothesis that endotoxin may be responsible for some of the tissue irritation associated with latex glove use. In addition, this material may be responsible for the enhancement of delayed and immediate hypersensitivity reactions to chemicals and proteins found in these products and offers a possible explanation for the disproportionate severity of these reactions.


Subject(s)
Endotoxins/pharmacology , Latex/adverse effects , Allergens/analysis , Dermatitis, Contact/etiology , Endotoxins/analysis , Humans , Hypersensitivity, Delayed/chemically induced , Hypersensitivity, Immediate/chemically induced , Latex/chemistry , Latex/immunology , Proteins/analysis
19.
J Urol ; 158(5): 1867-9, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9334619

ABSTRACT

PURPOSE: Recent studies have suggested that the primary site of metabolism for prostate specific antigen (PSA) is the liver. We evaluated men undergoing liver transplantation to determine whether chronic hepatic insufficiency affected serum PSA levels and whether improved hepatic function altered serum PSA levels. MATERIALS AND METHODS: Ten men with a mean age of 46 years (range 23 to 67) undergoing liver transplantation were evaluated. Liver function tests, including serum bilirubin, serum glutamic-oxaloacetic transaminase and serum glutamic pyruvic transaminase, as well as serum PSA were determined 1 day before and a mean of 12.6 months (range 4 to 18) after transplantation. RESULTS: Serum bilirubin and serum glutamic-oxaloacetic transaminase declined significantly after liver transplantation. There was no difference in mean serum PSA levels before and after liver transplantation. CONCLUSIONS: Our results suggest that severe hepatic dysfunction does not significantly alter the serum concentration of PSA. These data, combined with recent investigations demonstrating an intrahepatic mechanism for PSA elimination, suggest that the liver has a significant reserve to metabolize the relatively small quantities of PSA in the circulation.


Subject(s)
Liver Failure/metabolism , Liver Transplantation/physiology , Liver/metabolism , Prostate-Specific Antigen/blood , Adult , Aged , Humans , Liver Failure/surgery , Male , Middle Aged
20.
Ann Otol Rhinol Laryngol ; 106(9): 790-4, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9302915

ABSTRACT

In inflamed tissue, neutrophils produce tissue necrosis factors such as free oxygen radicals. We investigated the role of neutrophils in random flap survival using the tissue neutrophil marker myeloperoxidase (MPO), an in whole blood using flow cytometry with the neutrophil activation marker 2'7'dichlorofluorescein diacetate. Hypopigmented pigs were treated with the experimental 21-aminosteroid lipid antioxidant U-74389G (oxygen free radical scavenger) before dorsal random skin flaps were elevated. Extent of flap survival was measured by surface planimetry 7 days after surgery. Mean flap survival was 64.1% +/- 3.4% in the 3-mg/kg-treated group, and 68.0% +/- 3.4% in the 1-mg/kg-treated group-both significantly greater than the survival in vehicle-treated controls (48.6% +/- 2.3%). We measured MPO in tissue extracts using an enzyme-linked immunoassay, which showed less MPO in treated animals than in controls. Flow cytometry results were nonspecific. These data suggest that U-74389G improves random skin flap viability by inhibiting neutrophil infiltration into the flap.


Subject(s)
Antioxidants/pharmacology , Graft Survival , Neutrophil Activation/drug effects , Skin/drug effects , Surgical Flaps , Animals , Dermatologic Surgical Procedures , Swine
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