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Medical Technology (MD)
Our Lady of Fatima University
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TYPES OF SAFETY HAZARDS
Biologic Source: Infectious agent Possible injury: bacterial, fungal, viral, or parasitic infections Sharps Source: needles, lancets, broken glass Possible injury: cuts, punctures, or blood borne pathogens exposure Chemical Source: preservatives and reagents Possible injury: exposure to toxic, carcinogenic, or caustic agents Radioactive Source: equipment and radioisotopes Possible injury: radiation exposure Electrical Source: ungrounded or wet equipment, frayed cords Possible injury: burns or shock Fire/explosive Source: open flames, organic chemicals Possible injury: burns or dismemberment Physical Source: wet floors, heavy boxes, patients Possible injury: falls, sprains, or strains Fomites soiled inanimate objects CHAIN OF INFECTION Infectious Agent Bacteria, fungi, parasites, viruses Reservoir Humans Animals Insects Fomites Blood/body fluids
Break the link: disinfection, hand hygiene Portal of Exit Nose Mouth Mucous membranes Specimen collection
Break the link: Sealed biohazardous waste containers Sealed specimen containers Hand hygiene Standard precautions Susceptible Hosts Patients Elderly Newborns Immunocompromised Health-care workers
Break the Link: Immunizations Patient isolation Nursery precautions Healthy lifestyle Means of Transmission Direct contact Touches the patient Airborne Dried aerosol particles Droplet Inhales materials Vehicle Ingestion of contaminated substance Vector Animal/ bite
Break the Link: Hand hygiene Standard precautions
PPE
Patient isolation Portal of Entry Nose Mouth Mucous membranes Skin Unsterile equipment
Break the Link: Hand hygiene Standard precautions PPE Sterile equipment Blood Borne Pathogens Hepatitis B virus (HBV) Hepatitis C virus (HCV)puncture-resistant, leak-proof container Human immunodeficiency Virus (HIV) Universal Precautions all patients are considered to be possible carriers of bloodborne pathogens Body Substance Isolation (BSI) Modification of Universal Precautions personnel should wear gloves at all times when encountering moist body substances. Standard Precautions Combined major features of UP and BSI guidelines HANDWASHING Procedure 1. Wet hands with warm water. Do not allow parts of body to touch the sink. 2. Apply soap, preferably antimicrobial. 3. Rub to form a lather, create friction, and loosen debris. Thoroughly clean between the fingers and under the fingernails for at least 20 seconds; include thumbs and wrists in the cleaning 4. Rinse hands in a downward position to prevent recontamination of hands and wrists hands in a downward position to prevent recontamination of hands and wrists. 5. Obtain paper towel from the dispenser. 6. Dry hands with paper towel. 7. Turn off faucets with a clean paper towel to prevent contamination. Biological Waste Disposal All biologic waste, except urine, must be placed in appropriate containers labeled with the biohazard symbol Chemical Spills and Exposure Skin contact: flush the area with large amounts of water for at least 15 minutes Sharp Hazards Disposed into puncture-resistant, leak proof container Fire/Explosive Hazards “RACE”
R: Rescue A: Alarm C: Contain E: Evacuate HAZARDOUS MATERIALS CLASSIFICATION BLUE HEALTH HAZARD 4: Deadly 3: Extreme Danger 2: Hazardous 1: Slightly Hazardous 0: Normal Material RED FIRE HAZARD/FLASH POINT 4: Below 73 F 3: Below 100 F 2: Below 200 F
American Osteopathic Association (AOA), American Society of Histocompatibility and Immunogenetics (ASHI), Commission on Laboratory Assessment (COLA) Criteria for Urine Specimen Rejection Unlabeled containers Nonmatching labels and requisition forms Contaminated specimens with feces or toilet paper Containers with contaminated exteriors Insufficient volume of urine Improperly transported or preserved specimens Delay between time of collection and receipt in the laboratory HISTORY AND IMPORTANCE Hippocrates 5 th century BCE Wrote a book on “uroscopy” Color Charts 1140 AD Thomas Bryant Book about Charlatans “pisse” prophets Fredderick Dekkers 1694 Discovery of albuminuria in boiling urine Microscope 17 th century Thomas Addis: quantitating microscopic sediment Richard Bright Urinalysis: routine patient examination (1827) Urinalysis Beginning of laboratory medicine UTILITIES OF ANALYSIS 1. aid in diagnosis of disease 2. screen asymptomatic undetected diseases 3. monitor progress of disease URINE FORMATION Urine Ultrafiltrate of plasma 1200 mL Average daily urine output URINE COMPOSITION Urine 95% water 5% solutes PRIMARY COMPONENTS IN NORMAL URINE Urea Metabolic waste product Breakdown of protein and amino acids Creatinine Creatine metabolism (muscles) Uric Acid Nucleic acid breakdown (food and cells) Chloride Major inorganic solid dissolved in urine Sodium From salt Potassium Combined with chloride and salts Phosphate Combines with sodium (buffer) Ammonium Blood and tissue fluid acidity Calcium Combines with chloride, sulfate, and phosphate URINE VOLUME Oliguria Decrease in urine output <1 mL/kg/hr: infants <0 mL/kg/hr: children <400 mL/day: adults Anuria Cessation of urine flow severe acute nephritis, Hg poisoning, obstructive uropathy, kidney failure Nocturia Night (increase in nocturnal excretion) >500 mL Polyuria Increase in daily urine volume >2 L/day: adults >2-3 mL/kg/day: children Associated with diabetes mellitus and diabetes insipidus Diuresis Transitory increase in urine volume Diabetes insipidus Defect in pancreatic production and insulin function Decreased ADH Diabetes mellitus High specific gravity
Polydipsia Increased ingestion of water SPECIMEN COLLECTION Specimen Clean, dry, leak-proof container wide mouth container, flat bottom 50 mL Recommended capacity 12 mL Microscopic analysis Labels Name, date and time of collection Attached to container not on lid SPECIMEN REJECTION Improperly labeled Nonmatching labels Contaminated specimens Insufficient quantity CHANGES IN UNPRESERVED URINE INCREASED Odor Breakdown of urea to ammonia pH Urease-producing bacteria/loss of CO Nitrite Multiplication of nitrate-reducing bacteria Bacteria Multiplicaton Color Oxidation/reduction of metabolites Modified/darkened DECREASED Clarity precipitation Glucose Glycolysis and bacterial use Ketones Volatilization and bacterial metabolism Bilurubin Exposure to light/photo oxidation to biliverdin Red and white blood cells and casts Disintegration Trichomonas Loss of motility URINE PRESERVATIVES Refrigeration Prevents bacterial growth Precipitates amorphous phosphates and urates Phenol Causes odor change Toluene Floats on surface and clings to pipettes Thymol Preserves glucose and sediments Interferes with acid precipitation tests for protein Boric acid Prevent bacterial growth and metabolism Interferes with drug and hormone analysis Formalin (formaldehyde) Excellent sediment preservative Reducing agent and interferes chemical tests Sodium fluoride Prevents glycolysis preservative for drug analyses Saccommano Fixative Preserves cellular elements Cytology TYPES OF URINE SPECIMENS PURPOSE Random Routine screening 12-hour (timed) Addis count Afternoon specimen (2-4 pm) Urobilinogen determination Fastomh Diabetic screening/monitoring 2-hour Postprandial Diabetic monitoring First Morning Routine screening Pregnancy tests Orthostatic protein Ideal screening specimen Prevent false negative pregnancy tests Concentrated specimen 24-hour (timed) Quantitative chemical tests Hormone studies Catheterized Bacterial culture Midstream clean-catch Routine screening Bacterial culture Safer, less traumatic method
Menstrual contamination Port Wine Porphyrins Red Brown Methemoglobin Myoglobin Brown Homogentisic acid (alkaptonuria) Black Malignant melanoma Melanin or melanogen Phenol derivatives: Interfere with copper reduction tests Argyrol (antiseptic) Methyldopa or levodopa: antihypertensive Metronidazole (Flagyl) Uroerythrin Precipitation of amorphous urates CLARITY transparency or turbidity Clear No visible particulates Hazy Few particulates Cloudy Many particulates NONPATHOLOGIC TURBIDITY Squamous epithelial cells Mucus Amorphous phosphates, carbonates, urates Semen, spermatozoa Fecal contamination Radiographic contrast media Talcum powder Vaginal creams PATHOLOGIC CAUSES OF URINE TURBIDITY RBCs WBCs Bacteria Yeast Nonsquamous epithelial cells Abnormal crystals Lymph fluid Lipids SPECIFIC GRAVITY 1 Specific gravity of plasma filtrate entering glomerulus Isosthenuric Consistent 1 SG <1 Hyposthenuric >1 Hypersthenuric Urinometer sink at 1 in distilled water, calibrated at 20 0 C less accurate 0 added or subtracted Protein: subtract 0 every g/dL Glucose: subtract 0 every g/dL Refractometer concentration of dissolved particles refractive index calibrated with 1 distilled water 3% NaCl (1), 5% NaCl (1), 7% NaCl (1), or 9% sucrose (1). Acceptable tolerance: target ± 0. Harmonic Oscillation Densitometry Mass gravity meter: Yellow IRIS Principle: sound waves oscillate Osmolality Changes in colligative properties Reagent Strip pKa changes of a polyelectrolyte GUIDELINES FOR STANDARDIZING MICROSCOPIC EXAMINATION OF URINE SEDIMENT a. Volume of urine examined 10, 12, or 15 mL b. Speed of centrifugation 400 g c. Length of centrifugation 5 minutes d. Sediment preparation 0 or 1 mL left after decantation e. Volume of sediment examined 20 μL or 0 mL f. Sediment examination At least 10 LPFs and 10 HPFs APPROACHES TO QUALITY MANAGEMENT Total Quality Management teams, processes, statistics reduce errors
Continuous Quality Improvement improve practices Patients: ultimate customers of CQI Six Sigma hands-on process with the single mantra of improvement POSSIBLE CAUSES OF URINE ODOR Aromatic Normal Ammoniacal Freshly voided Foul, ammonia-like Bacterial decomposition, urinary Fruity, sweet Ketones (diabetes mellitus, diabetes ketoacidosis) Maple syrup Maple syrup urine disease Sulfur odor Cystine disorders Mousy Phenylketonuria Rancid Tyrosinemia Sweaty feet Isovaleric acidemia Mercaptan Asparagus, garlic, and eggs Rotting fish Timethyl aminuria Fecaloid Rectovesicular fistula Cabbage/hops Methionine malabsorption Bleach Contamination TRANSPARENCY Clear No visible particulates, transparent Hazy Few particulates, print easily seen Cloudy Many particulates, print blurred Turbid Print cannot be seen Milky May precipitate or be clotted CHEMICAL EXAMINATION OF URINE Reagent Strip Technique 1. Drip briefly. 2. Blot horizontally. Handling and Storing Reagent Strips 1. Bottled is resealed immediately. 2. Stored at room temperature (<30 0 C) but do not refrigerate. 3. Do not use pass expiration date. Quality Control of Reagent Strips Checking of control: every 24 hours (every beginning of shift)
Confirmatory Testing different reagent/methodologies to detect same substances pH Morning Specimen: 5 to 6. Normal Random Samples: 4 to 8. Purpose: detect acid-base disorders CAUSES OF ACID AND ALKALINE URINE ACID URINE Emphysema Diabetes mellitus Starvation Dehydration Diarrhea Presence of acid-producing bacteria (E. coli): false positive High-protein diet Cranberry juice Medications (methenamine mandelate [Mandelamine], fosfomycin tromethamine [Monurol] ALKALINE URINE Hyperventilation Vomiting Renal tubular acidosis Presence of urease-producing bacteria Vegetarian diet Old specimens pH REAGENT STRIP Reagents Methyl red, bromthymol blue Sensitivity Multistix: 5 to 8 in 0 increments
Quaternary ammonium compounds (detergents) Antiseptics, chlorhexidine Loss of buffer from prolonged exposure of the strip to the specimen reagent High specific gravity False negative Proteins other than albumin Microalbuminuria Microalbumin Testing Immunologic Tests Micral Test Principle: Enzyme immunoassay Sensitivity: 0 to 10 mg/dL Reagents: Gold-labeled antibody B-galactosidase Chlorophenol red galactoside Interference: False negative: Dilute urine
ImmunoDip Principle: Immunochromographics Sensitivity: 1 to 8 mg/dL Reagents: Antibody-coated blue latex particles Interference: False-negative: Dilute urine Glycogenesis glucose to glycogen for storage Glycogenolysis breakdown of glycogen to glucose Clinical Significance of Urine Glucose <15 mg/dL Hyperglycemia Associated Diabetes mellitus Pancreatitis Pancreatic cancer Acromegaly Cushing syndrome Hyperthyroidism Pheochromocytoma Central nervous system damage Stress Gestational diabetes Renal Associated Fanconi syndrome Advanced renal disease Osteomalacia Pregnancy Copper Reduction Test (Clinitest) copper sulfate to cuprous oxide Benedict solution Brick red precipitate Ketones Products of acetone, acetoacetic acid, and β -hydroxybutyrate Ketonuria Type 1 DM: insulin deficiency Gerhardt’s, Lindeman’s Diacetic acid Frommer’s, Walhauster’s, Lange’s Jackson-Taylor’s Rantzmann’s, Lieben’s
acetone
Legal’s, Rothera’s, Acetest, Ketostix Diacetic acid and acetone Osterberg, Hart’s test B-hydroxybutyric acid Ketone Reagent Strip Reagents Sodium nitroprusside Glycine (Chemstrip) Sensitivity Sensitivity: Multistix: 5 to 10 mg/dL acetoacetic acid Chemstrip: 9 mg/dL acetoacetic acid; 70 mg/dL acetone False Positive Phthalein dyes Highly pigmented red urine Levodopa Medications containing free sulfhydryl groups
False Negative Improperly preserved specimens BLOOD Hematuria Blood present in urine Hemoglobinuria Product of red cell destruction/lysis of red blood cells Causes of Hematuria renal calculi, glomerular diseases, tumors, trauma, pyelonephritis, exposure to toxic chemicals, and anticoagulant therapy Hemosiderin large yellow brown granules of denatured ferritin Myoglobin Clear red-brown urine Associated with rhabdomyolysis Clinical Significance of a Positive Reaction for Blood Hematuria Renal calculi Glomerulonephritis Pyelonephritis Tumors Trauma Exposure to toxic chemicals Anticoagulants Strenuous exercise Hemoglobinuria Transfusion reactions Hemolytic anemias Severe burns Infections/malaria Strenuous exercise/red blood cell trauma Brown recluse spider bites Myoglobinuria Muscular trauma/crush syndromes Prolonged coma Convulsions Muscle-wasting diseases Alcoholism/overdose Drug abuse Extensive exertion Cholesterol-lowering statin medications Blood Reagent Strip Reagents Multistix: Diisopropylbenzene dihydroperoxide and 3,3’,5,5’-tetramethylbenzidine Chemstrip: dimethyldihydroperoxyhexane and tetramethylbenzidine Sensitivity Multistix: 5 to 20 RBCs/mL, 0 to 0 mg/dL hemoglobin Chemstrip: 5 RBCs/mL, hemoglobin corresponding to 10 RBCs/mL False positive Strong oxidizing agents Bacterial peroxidases Menstrual contamination False negative High specific gravity/crenated cells Formalin Captopril High concentrations of nitrite Ascorbic acid greater than 25 mg/dL Unmixed specimens Tests to differentiate hemoglobin and myoglobin Ammonium sulfate method BILIRUBIN Presence in urine indicates early liver disease highly pigmented yellow compound degradation product of hemoglobin Tests for Bilirubin a. Foam Shake Test b. Oxidation Test (Gmelin or Fouchet’s method) Acidic oxidation of bilirubin into a rainbow array of colors: green (biliverdin), blue
Multistix False Negative:
Old specimens Preservation in formalin Chemstrip False Positive:
Highly pigmented urine Chemstrip False Negative:
Old specimens Preservation in formalin High concentrations of nitrite Nitrite Rapid screening for Urinary Tract Infection Clinical Significance of Urine Nitrite Cystitis Pyelonephritis Evaluation of antibiotic therapy Monitoring of patients at high risk for urinary tract infection Screening of urine culture specimens Greiss Reaction nitrite at acidic pH reacts with an aromatic amine (para- arsanilic acid or sulfanilamide) to form a pink azodye Nitrite Reagent Strip Reagents Multistix: p-arsanilic acid Tetrahydrobenzo(h)-quinolin-3- ol Chemstrip: Sulfanilamide, hydroxytetrahydro benzoquinoline Sensitivity Multistix: 0 to 0 mg/dL nitrite ion Chemstrip: 0 mg/dL nitrite ion False Negative Nonreductase-containing bacteria Insufficient contact time between bacteria and urinary nitrate Lack of urinary nitrate Large quantities of bacteria converting nitrite to nitrogen Presence of antibiotics High concentrations of ascorbic acid High specific gravity False Positive Improperly preserved specimens Highly pigmented urine Leukocyte Esterase presence of leukocytes that have been lysed Indoxylcarbonic acid ester: purple azodye Leukocyturia without bacteriuira Trichomonas, Chlamydia, yeast, and inflammation of renal tissues Leukocyte Esterase Reagent Strip Reagents Multistix: Derivatized pyrrole amino acid ester Diazonium salt Chemstrip: Indoxylcarbonic acid ester Diazonium salt Sensitivity Multistix: 5 to 15 WBC/hpf Chemstrip: 10 to 25 WBC/hpf False Positive Strong oxidizing agents Formalin Highly pigmented urine, nitrofurantoin False Negative High concentrations of protein, glucose, oxalic acid, ascorbic acid, gentamicin, cephalosporins, tetracyclines; inaccurate timing Clinical Significance of Urine Specific Gravity Monitoring patient hydration and dehydration Loss of renal tubular concentrating ability Diabetes insipidus Determination of unsatisfactory specimens due to low concentration Urine Specific Gravity Reagent Strip
Reagents Multistix: Poly (methyl vinyl ether/maleic anhydride) bromthymol blue Chemstrip: Ethylene glycol diaminoethyl ether tetraacetic acid, bromthymol blue Senstivity 1 to 1. False Positive High concentrations of protein False Negative Highly alkaline urines (greater than 6) Macroscopic Screening and Microscopic Correlations Color Blood Clarity Hematuria versus hemoglobinuria/ myoglobinuria pathologic or nonpathologic cause of turbidity Blood RBC, RBC casts Protein Casts, cells Nitrite Bacteria, WBCs Leukocyte esterase WBCs, WBC casts. Bacteria Glucose Yeast Centrifugation Urine Sediment Stain Characteristics Sternheimer-Malbin Delineates structure and colors of nucleus and cytoplasm Identifies WBCs, epithelial cells, and casts Toluidine blue nuclear detail Enhances nuclear detail 2% acetic acid Lyses RBCs and enhances nuclei of WBCs Distinguishes RBCs from WBCs, yeast, oil droplets, and crystals Lipid stains: Oil Red O and Sudan III triglycerides and neutral fats orange red Identify free fat droplets and lipid-containing cells and casts Gram stain Differentiates gram positive and gram negative bacteria Identifies bacterial casts Hansel stain Methylene blue and eosin Y stains eosinophilic granules Identifies urinary eosinophils Prussian blue stain Stains structures containing iron Identifies yellow brown granules of hemosiderin in cells and casts Expected Staining Reactions of Urine Sediment Constituents RBCs Neutral: pink to purple Acid: pink (unstained) Alkaline: purple WBCs (dark-staining cells) Nuclei: Purple Cytoplasm: purple granules Glitter cells (Sternheimer-Malbin positive cells) Nuclei: colorless or light blue Cytoplasm: pale blue or gray Glitter cells: Brownian movement Renal tubular epithelial cells Nuclei: dark shade of blue purple Cytoplasm: light shade of blue purple Bladder tubular epithelial cells Nuclei: Blue purple Cytoplasm: Light purple Squamous epithelial cells Dark shade of orange purple Light purple or blue Hyaline casts Pale pink or pale purple Slightly darker than mucous threads Coarse granular inclusion casts Dark purple granules in purple matrix Finely granular inclusion casts Fine dark purple granules in pale pink or pale purple matrix Waxy casts Pale pink or pale purple Darker than hyaline casts Distinct broken ends Fat inclusion casts Fat globules unstained Rare: polarized tight: double refraction Red cell inclusion casts Pink to orange red
Clue cells: Gardnerella vaginalis coccobacilli Transitional Cells Appearance Spherical, polyhedral, or caudate with centrally located nucleus Syncytia Increased numbers of transitional cells in pairs or clumps Catheterization
Abnormal morphology indicates malignancy or viral infection Renal Tubular Epithelial Cells Appearance Rectangular, columnar, round, oval or, cuboidal with an eccentric nucleus possibly bilirubin stained or hemosiderin-laden Most clinically significant >2/hpf = tubular injury Bilirubin laden hepatitis Hemosiderin laden Hemolytic conditions Oval Fat Bodies Appearance Highly refractile RTE cells Staining Sudan III Oil Red O Lipiduria Damage to glomerulus caused by nephrotic syndrome, severe tubular necrosis, diabetes mellitus Large fat laden histiocytes Lipid storage diseases Bacteria Appearance Small spherical and rod shaped structures Staphylococcus and Enterococcus Causes UTI Yeast Appearance Branched, mycelial form Small, oval, refractile structures with buds or mycelia Candida albicans Seen in urine of diabetic patients Most common Parasites Trichomonas vaginalis Most frequent parasite in urine Trophozoite: pear shaped with undulating membrane Associated with vaginal inflammation motile, flagellated Schistosoma haematobium Bladder parasite Ova: appear in the urine Enterobius vermicularis Most common contaminant pinworm Spermatozoa Appearance Tapered oval head with long, thin tail Mucus uromodulin Major constituent of mucus Thread like structures with low refractive index Single or clumped Casts Examinaion Lower power magnification Cylindruria presence of urinary casts Hyaline Casts Colorless, homogenous matrix RBC Casts damage to the glomerulus (glomerulonephritis) WBC Casts Pyelonephritis, interstitial nephritis (+eosinophils) Bacterial Casts Bacilli bound to protein matrix Epithelial Cell RTE cells attached to protein matrix Granular Cast Stasis of urine flow Fatty Casts Nephrotic syndrome Fat droplets and oval fat bodies attached to protein matrix Lipiduria Waxy Casts Chronic renal failure/ extreme urine stasis
Highly refractile cast with jagged ends and notches Final phase of cast degeneration Broad Casts renal failure casts Urinary Casts liver disease, inborn errors of metabolism, or renal damage Crystals precipitation of urine solutes Normal Crystals Seen in Acidic Urine Uric Acid Yellow brown (rosettes, wedges) Increased in gout, leukemia, and Lesch Nyhan syndrome Amorphous Urates Brick dust or yellow brown Refrigerated specimens Calcium Oxalate Colorless (envelopes, oval, dumbbell) Dihydrate: most common form of calcium oxalate crystal (octahedral envelope) Ethylene glycol poisoning, renal Calculi Acid Urates Small brown spheres; may cluster in pairs and triplets Sodium Urates Colorless birefringent needles Calcium Sulfate Long, thin colorless needles or prisms Hippuric Acid Yellow brown or colorless, needles, rhombic plates and four-sided prisms containing benzoic acid Radiographic Dye Flat, colorless, notched rhombic plates; highly birefringent Soluble in 10% NaOH markedly elevated SG (>1) Sulfonamide Crystals Colorless to yellowbrown needles, sheaves of wheat,and rosettes Soluble in acetone Ampicillin Crystals Colorless needles that tend to form bundles following refrigeration Normal Crystals Seen in Alkaline Urine Phosphates represent the majority of the crystals seen in alkaline urine Amorphous Phosphates White colorless Milky white granular Calcium Phosphate Colorless Flat rectangular plates/thin prisms(rosette formations) Triple Phosphate Colorless (“coffin lids”) ammonium magnesium phosphate birefringent under polarized light Ammonium biurate Yellow brown (“thorny apples”) Soluble in acetic acid and heat Calcium carbonate Colorless (dumbbells) Soluble in acetic acid with evolution of gas Uric Acid rhombic, four-sided flat plates (whetstones), wedges, and rosettes similar to cystine crystals Abnormal Urine Crystals Cystine Crystals Cystinuria colorless, hexagonal plates and may be thick or thin Cholesterol Crystals rectangular plate with a notch in one or more corners Nephrotic Syndrome Highly birefringent Lipiduria Leucine Yellow (concentric circles) Liver disease Tyrosine Colorless yellow needles Liver disease Bilirubin Yellow Clumped needles or granules
Week 10 AUBF - AUBF
Course: Medical Technology (MD)
University: Our Lady of Fatima University
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