BACKGROUNDBacterial infection can pose a substantial diagnostic dilemma. (99m)Tc-labeled ciprofloxacin (CPF) was developed as a biologically active radiopharmaceutical to diagnose infection. In the present research, we studied the biodistribution and imaging properties of infection tracer (99m)Tc-CPF in a mouse model of infection.

METHODSCPF was labeled with (99m)Tc and the radiochemical purity and labeling rate were measured. A mouse model of infection was established. We then determined the biodistribution of (99m)Tc-CPF and conducted the whole body scintigraphy of the animal model.

RESULTS(99m)Tc-Ciprotech was stable for at least 6 hours at room temperature. The labeling rate of CPF by (99m)Tc was over 90%. Clearance of radioactivity mainly occurred in the liver and kidney, and the clearance from blood was rapid. Both biodistribution and imaging results showed higher uptake of (99m)Tc-CPF at sites of infection. The infectious tissue/normal tissue ratio peak was 4.30 at 4 hours after injection.

CONCLUSIONS(99m)Tc-CPF is a sensitive radiopharmaceutical for scintigraphy of infectious lesions and it is easy to prepare.

Animals ; Anti-Infective Agents ; chemistry ; pharmacokinetics ; Bacterial Infections ; diagnosis ; Ciprofloxacin ; chemistry ; pharmacokinetics ; Disease Models, Animal ; Isotope Labeling ; methods ; Mice ; Mice, Inbred BALB C ; Organotechnetium Compounds ; chemistry ; Tissue Distribution

AIMTo explore the synthetic methods of polypeptides containing new heart of kidney imaging agents.

METHODS AND RESULTSFive new target chelators--2-N-(2'-s-triphenylmethylacetyl) amino-(N'-2"-N",N"-diethylethylamine) phenylpropamide (MPNE), 2-N-(2'-s-triphenylmethyl acetyl) amino-(N'-2"-N",N"-dimethylethylamine) phenylpropamide (MPNM), 2-N-(2's-triphenylmethylacetyl) amino-3-methyl-(N'-2"-N",N"-dimethylethylamine) butyramide (MVNM), 2-N-(2'-s-triphenyl methylacetyl) amino-3-methyl-(N'-2"-N",N"-diethylethylamine) butyramide (MVNE), 2-N-(2'-s-triphenylmethylacetyl) amino-(N'-acetylglycine) phenylpropamide (MPG2)--were synthesized through five steps with mercaptoacetic acid as primitive materials, all of which were identified on the basis of spectroscopic data, such as IR, 1HNMR, MS or elementary analysis. The protection of the mercapto group was improved and the relatively new reaction condition of active ester with amino acid is developed. All the chelators were labeled with Technetium-99m and their biological activities in mice given in ID values was tested to explore new heart imaging agents, where ID is the percentage injected dose per organ. The ID was determined by in vivo biodistribution study. Tc-99m complexes 0.1 mL was injected into the laterial tail vein of 3 anaesthetised rats. At 2, 5, 10, 30, 60 min post-injection, rats were sacrificed by decapitation, bled from the neck and dissected. Organs were removed at dissection. The radioactivities in various organs were determined in an automatic twin crystal gamma counter.

CONCLUSIONThe bio-distribution results in mice indicate that 99Tcm-MVNM have higher heart uptake (ID = 8.40%/g, 2 min post-injection) and quicker blood clearance (ID = 4.3%/g, 60 min post-injection); 99Tcm-MPNE and 99Tcm-MPNM also have fairly high heart uptake and quick blood clearance; 99Tcm-MPG2 has better kidney accumulation and higher activity ratios of kidney to blood (about 4).

Amides ; chemical synthesis ; pharmacokinetics ; Animals ; Kidney ; metabolism ; Mice ; Molecular Structure ; Myocardium ; metabolism ; Organotechnetium Compounds ; chemical synthesis ; pharmacokinetics ; Peptides ; chemical synthesis ; chemistry ; pharmacokinetics ; Sulfides ; chemical synthesis ; pharmacokinetics ; Tissue Distribution

BACKGROUND: Some researchers have questioned the necessity of adjusting glomerular filtration rate (GFR) by body surface area (BSA). We compared the relationship between estimated GFR (eGFR) and radionuclide GFR (rGFR) with or without BSA adjustment by comparing the results obtained using various formulae with those obtained using 2 new proposed formulae. METHODS: A retrospective study was performed using 204 Korean individuals whose GFR had been estimated by the (99m)Tc-diethylenetriaminepentaacetic acid method between March 2004 and July 2008. We used the modification of diet in renal disease (MDRD) II formula, Mayo clinic quadratic (MCQ) formula, Cockcroft-Gault (CG) formula, and lean body mass-adjusted CG formula. Two new formulae, skeletal muscle mass index (SMI)-adjusted CG formula and SMIx3.4/SCr, were proposed by us. We analyzed each parameter with Pearson's correlation coefficient and also obtained the bias values. RESULTS: BSA did not satisfy the fundamental prerequisites of an adjustment factor for rGFR. MDRD II and MCQ GFR estimates demonstrated higher Pearson's correlation coefficient with BSA-unadjusted rGFR than they did with BSA-adjusted rGFR. The other GFR formulae estimates showed better correlation with rGFR and more favorable bias (P<0.001) when both GFR estimates and rGFR values were BSA-unadjusted. SMI-adjusted CG and SMIx3.4/SCr GFR estimates demonstrated correlation with rGFR and bias values similar to those of the MDRD II and CG GFR estimates. CONCLUSIONS: We suggest that absolute, non-corrected GFR and GFR estimate be preferred in daily practice. The absolute, non-corrected GFR and GFR estimate are considered helpful for patients with eGFR< or =60 mL/min/1.73 m2. We also recommend the clinical use of the new formulae, SMI-adjusted CG and SMIx3.4/SCr (BSA-unadjusted).
Adult ; Aged ; Aged, 80 and over ; Algorithms ; Body Surface Area ; Creatinine/blood ; Female ; *Glomerular Filtration Rate ; Humans ; Male ; Middle Aged ; Organotechnetium Compounds/chemistry ; Pentetic Acid/analogs & derivatives/chemistry ; Republic of Korea/ethnology ; Retrospective Studies

Thyrotoxic periodic paralysis (TPP) is a rare manifestation of hyperthyroidism characterized by muscle weakness and hypokalemia. All ethnicities can be affected, but TPP typically presents in men of Asian descent. The most common cause of TPP in thyrotoxicosis is Graves' disease. However, TPP can occur with any form of thyrotoxicosis. Up to our knowledge, very few cases ever reported the relationship between TPP and painless thyroiditis. We herein report a 25-yr-old Korean man who suffered from flaccid paralysis of the lower extremities and numbness of hands. The patient was subsequently diagnosed as having TPP associated with transient thyrotoxicosis due to painless thyroiditis. The paralytic attack did not recur after improving the thyroid function. Therefore, it is necessary that early diagnosis of TPP due to transient thyrotoxicosis is made to administer definite treatment and prevent recurrent paralysis.
Administration, Oral ; Adult ; Anti-Arrhythmia Agents/therapeutic use ; Humans ; Hypokalemic Periodic Paralysis/*diagnosis/drug therapy/etiology ; Male ; Organotechnetium Compounds/chemistry/diagnostic use ; Potassium Chloride/therapeutic use ; Propranolol/therapeutic use ; Radiopharmaceuticals/diagnostic use ; Thyroiditis/*complications/radiography/ultrasonography ; Thyrotoxicosis/*diagnosis/etiology