Alpha 1-antitrypsin is degraded and non-functional in chronic wounds but intact and functional in acute wounds: the inhibitor protects fibronectin from degradation by chronic wound fluid enzymes

Fluid obtained from chronic and acute wounds were examined for the presence of fibronectin, alpha 1-antitrypsin, and proteinases capable of degrading both proteins. Immunoblot analysis of fluids from ten chronic wounds revealed that fibronectin and alpha 1-antitrypsin were degraded in nine of ten samples. In contrast, both fibronectin and alpha 1-antitrypsin were intact in acute wound fluids. The degradation of the inhibitor and fibronectin occurred in the same wound fluids, and these two events correlated perfectly. Chronic or acute wound fluid proteins were coupled to benzamidine Sepharose 6B beads and incubated with fibronectin or alpha 1-antitrypsin. Chronic wound fluid proteins degraded fibronectin in the presence of ethylenediaminetetraacetate, leupeptin, cystatin, and pepstatin but not in the presence of phenylmethylsulfonyl fluoride. Acute wound fluids and normal human serum did not contain enzymes capable of degrading fibronectin. These data suggest that serine proteinases are responsible for fibronectin degradation in chronic wound fluids. Chronic wound fluids that contained degraded alpha 1-antitrypsin also contain proteinases capable of degrading alpha 1-antitrypsin from human serum. Acute wound fluids and normal human serum did not contain enzymes capable of degrading alpha 1-antitrypsin. The inhibitor from acute wound fluids bound to one of its targets, trypsin. In contrast, the fragment(s) of alpha 1-antitrypsin from chronic wound fluids did not bind trypsin. Chronic wounds associated with degraded fibronectin and the inhibitor contained ten- to forty-fold more elastase activity than acute wounds. The degradation of fibronectin by chronic wound fluid enzymes was inhibited by alpha 1-antitrypsin in a dose-dependent manner. Collectively, these results demonstrate that there are enzymes in chronic wounds that perturb the function of alpha 1-antitrypsin and allow fibronectin degradation by uninhibited serine proteinases.

Ceruloplasmin or fibronectin synergism with quartz dust on stimulating collagen gene transcription in human 2BS fibroblast

Human alpha 1(I), alpha 2(I) and alpha 1(III) cDNA probes and RNA dot hybridization were employed to quantitate collagen mRNA changes after adding silica dust into the media of human 2BS fibroblasts. At all dosages used (100, 200, 500 and 1000 micrograms), the alpha 1(I), alpha 2(I) and alpha 1(III) mRNA levels increased one day after dusting. At the same dosage of silica (100 micrograms), alpha 1(III) mRNA increased earlier than type I collagen mRNA did. The type I and type III collagen mRNA contents in the experimental groups were higher than those in control on days 3, 5, 7 and 9. The effect of ceruloplasmin (Cp) and fibronectin (Fn) on collagen mRNA synthesis was also studied, after adding silica dust, Cp or Fn into the media of human 2BS fibroblast. The results showed that Cp and Fn have stimulating effect on collagen mRNA production. When both Cp and silica dust were added into cell culture media, the collagen mRNA level was increased more than those of adding either Cp or silica dust alone. Similar situations were found for Fn. Cp (or Fn) synergism with silica dust on stimulating transcription of human collagen gene was suggested.

Canine bullous pemphigoid (BP): identification of the 180-kd canine BP antigen by circulating autoantibodies

Human bullous pemphigoid (BP) is an immune-mediated blistering disease characterized by autoantibodies against BP antigens (230/180 kd), which are constitutive glycoproteins of hemidesmosomes found in basal keratinocytes. Blistering diseases similar to human BP have been reported in dogs. IgG deposits at the basement membrane zone (BMZ) are a common feature of canine BP. Although circulating anti-BMZ IgG autoantibodies have been demonstrated in some cases of canine BP, the specific skin protein targeted by these autoantibodies has not been identified. In this study, we characterized the antigenic target of the autoantibodies in the serum from a 3-year-old castrated male Pit Bull Terrier with BP. Direct immunofluorescence of the patient's skin demonstrated IgG deposits at the dermal-epidermal junction. Indirect immunofluorescence demonstrated autoantibodies in the patient's serum that stained the epidermal roof of salt-split canine skin and left the dermal floor unstained. These serum autoantibodies did not stain normal intact dog skin but labeled intact bovine tongue. Direct immunoelectron microscopy of the dog's skin revealed IgG deposits within the hemidesmosomes of the basal keratinocytes. Western immunoblotting experiments showed that canine keratinocytes express both the 230-kd and 180-kd bullous pemphigoid antigens, and the autoantibodies from the patient's serum recognized the 180-kd bullous pemphigoid antigen in proteins extracted from canine and human keratinocytes. Canine BP has many parallel features with human BP including similar immune deposition of IgG within hemidesmosomes and a hemidesmosome-associated 180-kd glycoprotein target for circulating autoantibodies.

Effects of hyperbaric oxygen on S-180 sarcoma in mice

The contents of oxygen free radicals (OFRs) and malondialdehyde (MDA) in S-180 sarcoma tissues were measured in four groups of mice: an untreated normoxic group, a normoxic hyperbaric group, a hyperbaric oxygen group, and an HBO group treated with superoxide dismutase (SOD). Measurements were done by electron resonance and spectrophotometry, and observations were made on the volume, weight, necrosis incidence rate of sarcoma tissues, and mortality in all groups. The OFR and MDA content in sarcoma tissues in the HBO group was significantly higher than those of the control groups (P < 0.001); necrosis incidence of sarcoma tissues and the survival rate of mice were higher; the time required for necrosis was shorter, and the volume and weight of sarcoma tissues were smaller and lighter than those of the control groups (P < 0.01). The results suggest that SOD cannot completely eliminate OFRs produced by hyperbaric exposure, although the role of HBO in producing more OFRs can be counterbalanced by SOD to a certain degree. Apparently HBO can check the growth rate of sarcoma and accelerate the necrosis of S-180 sarcoma cells.

Monitoring human risk and exposure to trinitrotoluene (TNT) using haemoglobin adducts as biomarkers

Two studies were carried out in a trinitrotoluene (TNT) plant using TNT haemoglobin (TNT-Hb) adduct as a biomarker to study dose-adduct and adduct-response relationships. In the first study, TNT-Hb adduct levels were determined in 117 TNT-exposed workers in different working sites with different exposure conditions. External exposure was calculated from the inhaled air concentration plus skin contamination. TNT-Hb adduct levels in blood were significantly correlated with their external exposure to TNT. Two methods, HPLC-UV and CI-ELISA, were developed for measuring TNT-Hb adduct: good correlations (r = 0.77 and 0.86) were found between these 2 methods. In the second study, TNT cataract was used as an indicator of health effects. The prevalence of cataract and the degree of lenticular damage increased with the increase of blood TNT-Hb level.

Peptide-based radioimmunoassay for the two isoforms of the human insulin receptor

The insulin receptor exists in two isoforms differing by the absence (HIR-A) or presence (HIR-B) of 12 amino acids in the COOH-terminus of the alpha-subunit as a consequence of alternative splicing of exon 11. In this study, we developed a radioimmunoassay for the two isoforms employing antibodies raised against two peptides, one (Pep-12) corresponding to residues encoded by exon 11, and the other (Pep-13) corresponding to a COOH-terminal domain of the alpha-subunit which is common to both HIR-A and HIR-B isoforms. These peptides were iodinated and used as both ligands and standards. The assay is specific, highly reproducible, and sensitive with a detection limit of 10 fmol of receptor. One mole of purified insulin receptor, measured by Scatchard analysis, is read as one mole of receptor in the radioimmunoassay with either Pep-12 or Pep-13 as standards. The radioimmunoassay is applicable to the measurement of total content and relative abundance of the two isoforms in extracts from various tissues. We applied the radioimmunoassay to measure the relative abundance of the two isoforms in fat and muscle from normal, obese non-diabetic and non-insulin-dependent diabetic (NIDDM) subjects. Results demonstrate that expression of the low-affinity HIR-B form is significantly increased in obese and NIDDM subjects compared with control subjects. In addition, the increased expression of the HIR-B isoform was significantly correlated with both body mass index (r = 0.52; p = 0.006) and fasting glucose levels (r = 0.59; p = 0.001).

Partial characterization of matrix-associated serine protease inhibitors from human skin cells

Serine protease inhibitors have important regulatory roles in angiogenesis, intravascular fibrinolysis, wound healing, and cell migration. In this study, the extracellular matrix secreted by cultured human keratinocytes, foreskin fibroblasts, and SV-40-transformed human skin fibroblasts was analyzed for serine protease inhibitors by substrate reverse zymography. We found that the extracellular matrix deposited by these cells contained three inhibitors (M(r) 33,000, 31,000, and 27,000). These inhibitors protected the degradation of gelatin by trypsin and elastase, and of casein by plasmin. In contrast, the gelatinolytic activities of thermolysin and papain were not inhibited. Compared to untreated cells, cells treated with phorbol 12-myristate 13-acetate showed a two- to 10-fold increase in the expression of these inhibitors. Cycloheximide and actinomycin D decreased the cellular expression of these inhibitors, suggesting the involvement of de novo protein and mRNA synthesis. Antitrypsin activity of these inhibitors was resistant to heat and sodium dodecylsulfate, but was lost after reduction of disulfide bonds. The inhibitors bound specifically to trypsin and could be eluted from a trypsin column in active form. Collectively, these data suggest that the extracellular matrix deposited by keratinocytes and dermal fibroblasts contains active serine protease inhibitors.

Novel extracellular matrix-associated serine proteinase inhibitors from human skin fibroblasts

Serine proteinase inhibitors play a major role in the turnover of connective tissues. In this study, we isolated and determined partial amino-terminal amino acid sequence of trypsin/elastase/plasmin inhibitors (M(r) 33,000 and 31,000) from the extracellular matrix of SV40-transformed human skin fibroblasts. The antitrypsin activity of the inhibitors was monitored by substrate reverse zymography. Polyclonal antisera to alpha 1-antitrypsin, alpha 1-antichymotrypsin, alpha 2-antiplasmin, inter-alpha-trypsin inhibitor, plasminogen activator inhibitors-1 and -2, and a monoclonal antibody to protease nexin-1 did not label the 33-, 31-, and 27-kDa inhibitors. A computer search for amino acid sequence homology indicated that the 31-kDa inhibitor is novel. In contrast, the sequence of the 33-kDa inhibitor shared 70 to 90% homology with the amino-terminal sequence of a recently characterized 32-kDa trypsin/tissue factor inhibitor called tissue factor pathway inhibitor-2. The 33- and 31-kDa inhibitors bind to heparin-Sepharose and were recovered from the affinity beads as well as from the t12 FB extracellular matrix with 1 M NaCl. Based on these results, we propose that the extracellular matrix of human mesenchymal cells sequester a family of novel serine proteinase inhibitors.

Substance P induces degranulation of mast cells and leukocyte adhesion to venular endothelium

Substance P (SP), one of the established neurotransmitters, evokes an immunoinflammatory response involving leukocyte adhesion to venular endothelium and the degranulation of mast cells. The pathogenetic relationship between these responses, however, remains unresolved. In this study, we propose to examine the changes associated with the activation of mast cells, as well as leukocyte adhesion to venular endothelium by in vivo observation of the rat mesentery. The use of an in vitro assay for intracellular Ca2+ mobilization and the degranulation of mast cells demonstrated the significant upper shift of concentration response to SP (10(-4)-10(-5) M). In vivo experiments on the mesenteric microcirculation also showed that SP induced a significant increase in the number of degranulated mast cells as well as in the number of leukocytes adherent to the venular wall. Tranilast, a mast cell stabilizer, as well as SP antagonist (CP-96,345) significantly attenuated the extent of mast cell degranulation and leukocyte adhesion elicited by SP. Although an immunoneutralization against CD18 by WT-3 significantly attenuated the leukocyte adhesion, it had no influence on the mast cell degranulation after SP superfusion. These separate in vivo observations show that SP induces leukocyte adhesion to the venular endothelium, possibly through the degranulation of mast cells.

Snail hosts of Paragonimus in Asia and the Americas

We have undertaken a comprehensive review of snail hosts of Paragonimus world-wide exclusive of Africa based on modern malacological data, where available, and with consideration of the phylogeny of the snail groups involved. This is the first comprehensive review since those made by Chen (1979) and Chen et al. (1983), and there have been considerable taxonomic changes over the past decade. A number of names and concepts found in the medical malacological and parasitological literature up to the present time require revision or correction. There are vast radiations of snails of the superfamilies Cerithiacea and Rissoacea involved in the transmission of Paragonimus in China. We list 54 species world-wide of which 35(65%) occur in China. Revisions and corrections pertaining to China include: (i) The family Hydrobiidae does not occur in China or S.E. Asia, and the Pomatiopsidae should be used. (ii) The genus Bythinella is entirely European (Hydrobiidae: Amnicolinae). The so-called Bythinella of China belongs to the genus Erhaia (Pomatiopsidae). (iii) The generic name Pseudobythinella described from China is preoccupied, a junior synonym of Pseudobythinella Melville 1956, a fossil from England. All Chinese Pseudobythinella are now classified as Erhaia. (iv) Akiyoshia has been used as a generic name for some snails in Hunan transmitting Paragonimus. Akiyoshia is from Japan and biological/ecological data indicate that the Chinese taxon is not Akiyoshia. (v) The genus Tricula in recent Chinese literature is comprised of four genera determined by detailed comparative anatomical data: Tricula, Neotricula, Gammatricula, and Jinhongia. Shells cannot be used to discriminate among them. (vi) Tricula cristella has been consistently misidentified in collections in China and literature. However, genuine T. cristella does transmit Paragonimus skrjabini. (vii) Tricula minutoides in the Chinese literature has been misidentified, and specimens are T. cristella. (viii) The genus Melania and the family Melaniidae are used in the Chinese literature. The so-called melaniidae snails belong to the families Thiaridae, Pleuroceridae, and Melanopsidae. Asian Semisulcospira is pleurocerid while Melanoides and Tarebia are thiarid (ix) Semisulcospira libertina is correctly identified for populations ranging throughout Japan to Taiwan. This species is most probably not distributed throughout all south China, and intense systematic research on Semisulcospira is needed. A modern classification is given for snails transmitting Paragonimus.

[Response rate of small cell lung cancer treated with CE-CAP alternating chemotherapy]

From Sep. 1989 to Dec. 1992, 122 evaluable patients with small cell lung cancer (SCLC) treated with chemotherapy combined with radiotherapy in our hospital were analysed. There were 95 men and 27 women. The age ranged from 20 to 70 years. All were proven by pathology or cytology. They all did not receive previous treatment and had a measurable mass. Of them, 83 patients had limited disease (LD) and 39 extensive disease (ED). Using CE-CAP alternating chemotherapy, 48 LD and 27 ED were given two cycles, 35 LD and 12 ED four cycles. In this series, remission time was not evaluated because all patients received radiotherapy shortly after chemotherapy. Of 122 patients, 10 patients (8.2%) achieved CR, 89 (72.9%) PR, 18 (14.7%) S and 5 (4%) P. The total response rate was 81.1% (99/122), which is higher than that of COMVP and PE-CAV regimens. The response rates were 80.0% and 82.9% in two and four cycle groups, respectively. There was no significant difference between the two groups. The main toxicity observed was nausea, vomiting and bone marrow suppression, but were tolerated by the patients. In conclusion, CE-CAP regimen can be recommended as the treatment of choice in SCLC.

Characteristics of immunocomplex in autopsy tissues of hemorrhagic fever with renal syndrome

Using repeated PAP or repeated PAP and ABC immunocytochemical methods, we were able to demonstrate viral antigens, Ig and Clq in the tissues of 20 autopsy materials that had been preserved for 3-30 years. Serial paraffin sections were stained with the first antibodies against both viral antigens (G2 and Np) and human IgG, IgM, C3 and Clq. Immunocomplex, composed of viral antigen, IgG and Clq were found diffusely in the cells of each organ and extracellularly in the sera, various secretions and exudates. When stained by A25 etc, coarse granular antigen or inclusion bodies were found without demonstrable Ig and Clq. It was concluded that the immunocomplex in tissues of epidemic hemorrhagic fever in Shaanxi Province, China was both intracellular and extracellular and was perhaps soluble due to antigens in excess, with characteristics quite different from that of other immune diseases.

Abnormal fatty acid composition of lymphocytes of biotin-deficient rats

The relative proportions (% of total fatty acids) of odd-chain (15:0-29:0) and long-chain (22:0-30:0) saturated fatty acids in phospholipids of biotin-deficient rat lymphocytes were significantly increased as compared with biotin-supplemented rats, and the ratio of unsaturated fatty acids to saturated fatty acids in the former was significantly decreased mainly due to the reduced composition of polyunsaturated fatty acids in the omega-3, omega-6, and omega-9 pathway. The ratio of cis-vaccenic acid to palmitoleic acid in biotin-deficient rats was significantly lower than that in control rats, and was thought to be another important, but previously unreported indicator of biotin deficiency. These changes imply that the elongation and desaturation of unsaturated fatty acids are depressed in lymphocytes of biotin-deficient rats, and may contribute to the associated immunological dysfunction in biotin deficiency through abnormal prostaglandin metabolism and/or cell membrane functions.

Rat CINC/gro: a novel mediator for locomotive and secretagogue activation of neutrophils in vivo

The effects of rat CINC/gro, a member of the interleukin-8 family, on the endothelium-neutrophil interaction and transendothelial macromolecular leakage were studied in rat mesenteric microcirculation. Thirty minutes after superfusion with 10 nM CINC/gro, the number of neutrophils adherent to the venular endothelium and those migrated across the venules were significantly increased with a concomitant elevation of luminol-dependent chemiluminescence at the site of adhesion. Transendothelial macromolecular leakage as assessed by the relative length of venular wall stained with monastral blue B was also increased at 30 min after the start of CINC/gro superfusion. Pretreatments with a CD18-directed monoclonal antibody, WT-3 (1 mg/kg), significantly attenuated the increase in number of adherent and migrated neutrophils, the increase in luminol-dependent chemiluminescence, and the venular macromolecular leakage after the application of CINC/gro. These data suggest that CINC/gro is a novel stimulator that evokes not only locomotive but also secretagogue activation of neutrophils via a CD18-dependent mechanism in vivo.

Investigating the role of conserved residue Asp134 in Escherichia coli ribonuclease HI by site-directed random mutagenesis

The role of the conserved Asp134 residue in Escherichia coli ribonuclease HI, which is located at the center of the alpha V helix and lies close to the active site, was analyzed by means of site-directed random mutagenesis. Mutant rnhA genes encoding proteins with ribonuclease H activities were screened by their ability to suppress the ribonuclease-H-dependent, temperature-sensitive growth phenotype of E. coli strain MIC3001. Based on the DNA sequences, nine mutant proteins were predicted to have ribonuclease H activity in vivo. All of these mutant proteins were purified to homogeneity and examined for enzymic activity and protein stability. Among them, only the mutant proteins [D134H]RNase H and [D134N]RNase H were shown to have considerable ribonuclease H activities. Determination of the kinetic parameters revealed that replacement of Asp134 by amino acid residues other than asparagine and histidine dramatically decreased the enzymic activity without seriously affecting the substrate binding. Determination of the CD spectra indicated that none of the mutations seriously affected secondary and tertiary structure. The protein stability was determined from the thermal denaturation curves. All mutant proteins were more stable than the wild-type protein. Such stabilization effects would be a result of a reduction in the negative charge repulsion between Asp134 and the active-site residues, and/or an enhancement of the stability of the alpha V helix. These results strongly suggest that Asp134 does not contribute to the maintenance of the molecular architecture but the carboxyl oxygen at its delta 1 position impacts catalysis.

[Estimation of latency period of lung cancer]

A case-control study with time-related factors was conducted to estimate the latency period of lung cancer. This study included 168 incident male cases of lung cancer histologically confirmed and 336 control patients with non-neoplastic diseases. All patients were interviewed in the hospital wards from May 1987 to May 1990. Data concerning smoking, occupation, method of house heating and cooking fuel used from twelve time windows of looking forward and diet were obtained for three periods of time. A synthetical analysis of forward measures and backward measures were applied. By means of calculating accumulated effective exposure score and excess exposure fraction, the latency period of lung cancer was estimated using multivariate model. Latency of lung cancer is 54.48 years for indoor air pollution, and 56.17 years for total smoking. From estimating latency period of lung cancer from multivariate analysis, it was found that the latency of lung cancer could be affected by the effects of other factors. Therefore, measures which prolong latency period may be of use in the prevention of lung cancer.

Acylcarnitine profile in tissues and body fluids of biotin-deficient rats with and without L-carnitine supplementation

Since biotin-deficient (BD) rats are a good animal model for human multiple carboxylase deficiency and have low plasma free carnitine levels, short-chain acylcarnitine profiles in biotin-deficient rats with L-carnitine supplementation (BDC rats) and BD rats were investigated by fast-atom bombardment and tandem mass spectrometry and gas chromatography/mass spectrometry. By the latter method, 3-hydroxyisovalerylcarnitine was identified in BD rats, and showed the greatest accumulation among short-chain acylcarnitines in tissues of BD rats, while the tissue levels of propionic acid were more markedly elevated than those of 3-hydroxyisovaleric acid. The tissue levels of 3-hydroxyisovaleryl-carnitine were significantly lower and those of propionyl-carnitine were somewhat higher in BDC rats than in BD rats, while the tissue levels of propionic acid and 3-hydroxyisovaleric acid in BDC rats were lower than those in BD rats. These changes were more apparent in kidney than in other tissues. The amounts of urinary excretion of acylcarnitines were markedly larger, and those of 3-hydroxyisovaleric acid were somewhat smaller in BDC rats than in BD rats, while those of propionic acid were very low in BD and BDC rats as compared with those of 3-hydroxyisovaleric acid. It seems that the relationship between the concentrations of 3-hydroxyisovalerylcarnitine and those of propionylcarnitine reflects the unique metabolism of the related metabolites in tissues, especially in kidney, which may be influenced by their urinary excretion and the availability of free carnitine. These data in biotin deficiency suggest that carnitine supplementation is possibly beneficial for patients with holocarboxylase synthetase deficiency who respond incompletely to biotin therapy.

The effects of biotin deficiency on organic acid metabolism: increase in propionyl coenzyme A-related organic acids in biotin-deficient rats

Volatile organic acid levels in plasma and tissues and nonvolatile organic acid levels in urine of biotin-deficient (BD) rats were measured and compared with other factors of biotin deficiency. Biotin levels and the activities of propionyl coenzyme A (CoA) carboxylase (PCC) in the livers of these rats were decreased, respectively, to 22% +/- 3% and 3.6% +/- 0.3% of the average values of pair-fed controls. Plasma concentrations of propionate were higher (15 to 223 micrograms/mL) than those of controls (5 to 7 micrograms/mL), whereas plasma levels of 3-methylcrotonate were only minimally increased as compared with those of controls. Concentrations of these volatile acids in the tissues were similarly increased, although those in brain showed less remarkable increases as compared with levels in other tissues. In the urine of BD rats, large amounts of organic acids derived from propionyl CoA, as well as those from 3-methylcrotonyl CoA, were excreted. Plasma propionate levels were not apparently related to the severity of clinical symptoms, biotin levels, or carboxylase activities, but were related to the amounts of urinary ketone bodies, lactate, and some of the organic acids derived from branched-chain amino acids, including those from propionyl CoA.

Pharmacokinetics of [18F]fleroxacin in healthy human subjects studied by using positron emission tomography

Positron emission tomography (PET) with [18F]fleroxacin was used to study the pharmacokinetics of fleroxacin, a new broad-spectrum fluoroquinolone, in 12 healthy volunteers (9 men and 3 women). The subjects were infused with a standard therapeutic dose of fleroxacin (400 mg) supplemented with approximately 20 mCi of [18F]fleroxacin. Serial PET images were made and blood samples were collected for 8 h, starting at the initiation of the infusion. The subjects were then treated with unlabeled drug for 3 days (400 mg/day). On the fifth day, infusion of radiolabeled drug, PET imaging, and blood collection were repeated. In most organs, there was rapid accumulation of radiolabeled drug, with stable levels achieved within 1 h after completion of the infusion. Especially high peak concentrations (in micrograms per gram) were achieved in the kidney (> 34), liver (> 25), lung (> 20), myocardium (> 19), and spleen (> 18). Peak concentrations of drug more than two times the MIC for 90% of Enterobacteriaceae strains tested (> 10-fold for most organisms) were achieved in all tissues except the brain and remained above this level for more than 6 to 8 h. The plateau concentrations in tissues (2 to 8 h, in micrograms per gram +/- standard error of the mean) of drug were as follows: brain, 0.83 +/- 0.032; myocardium, 4.53 +/- 0.24; lung, 5.80 +/- 0.48; liver, 7.31 +/- 0.33; spleen, 6.00 +/- 0.47; bowel, 3.53 +/- 0.74; kidney, 8.85 +/- 0.64; bone, 2.87 +/- 0.29; muscle, 4.60 +/- 0.33; prostate, 4.65 +/- 0.48; uterus, 3.87 +/- 0.39; breast, 2.68 +/- 0.11; and blood, 2.35 +/- 0.09. Concentrations of fleroxacin in tissue were similar in males and females, before and after pretreatment with unlabeled drug.