In vitro activities of a new lipopeptide antifungal agent, FK463, against a variety of clinically important fungi

The in vitro antifungal activity and spectrum of FK463 were compared with those of amphotericin B, fluconazole, and itraconazole by using a broth microdilution method specified by National Committee for Clinical Laboratory Standards document M27-A (National Committee for Clinical Laboratory Standards, Wayne, Pa., 1997). FK463 exhibited broad-spectrum activity against clinically important pathogens including Candida species (MIC range, <==0.0039 to 2 microg/ml) and Aspergillus species (MIC range, <==0.0039 to 0.0313 microg/ml), and its MICs for such fungi were lower than those of the other antifungal agents tested. FK463 was also potently active against azole-resistant Candida albicans as well as azole-susceptible strains, and there was no cross-resistance with azoles. FK463 showed fungicidal activity against C. albicans, i.e., a 99% reduction in viability after a 24-h exposure at concentrations above 0.0156 microg/ml. The minimum fungicidal concentration (MFC) assays indicated that FK463 was fungicidal against most isolates of Candida species. In contrast, the MFCs of FK463 for A. fumigatus isolates were much higher than the MICs, indicating that its action is fungistatic against this species. FK463 had no activity against Cryptococcus neoformans, Trichosporon species, or Fusarium solani. Neither the test medium (kind and pH) nor the inoculum size greatly affected the MICs of FK463, while the addition of 4% human serum albumin increased the MICs for Candida species and A. fumigatus more than 32 times. Results from preclinical in vitro evaluations performed thus far indicate that FK463 should be a potent parenteral antifungal agent.

Efficacy of FK463, a new lipopeptide antifungal agent, in mouse models of disseminated candidiasis and aspergillosis

The efficacy of intravenous injection of FK463, a novel water-soluble lipopeptide, was evaluated in mouse models of disseminated candidiasis and aspergillosis and was compared with those of fluconazole (FLCZ) and amphotericin B (AMPH-B). In the candidiasis model, FK463 significantly prolonged the survival of intravenously infected mice at doses of 0.125 mg/kg of body weight or higher. In disseminated candidiasis caused by Candida species, including FLCZ-resistant Candida albicans, FK463 exhibited an efficacy 1.4 to 18 times inferior to that of AMPH-B, with 50% effective doses (ED(50)s) ranging from 0.21 to 1.00 mg/kg and 0.06 to 0.26 mg/kg, respectively, and was much more active than FLCZ. The protective effect of FK463 was not obviously influenced by the fungal inoculum size, the starting time of the treatment, or the immunosuppressed status of the host. The reduction in efficacy was less than that observed with FLCZ or AMPH-B. The efficacy of FK463 was also evaluated in the disseminated candidiasis target organ assay and was compared with those of FLCZ and AMPH-B. Efficacies were evaluated on the basis of a comparison between the mean log(10) CFU in kidneys in the groups treated with antifungal agents and that in control group. A single dose of FK463 at 0.5 mg/kg or higher significantly reduced the viable counts in kidneys compared with the numbers of yeast cells before treatment, and its efficacy was comparable to that of AMPH-B, while FLCZ at 4 mg/kg showed only a suppressive effect on the growth of C. albicans in the kidneys. In the disseminated aspergillosis model, FK463 given at doses of 0.5 mg/kg or higher significantly prolonged the survival of mice infected intravenously with Aspergillus fumigatus conidia. The efficacy of FK463 was about 2 times inferior to that of AMPH-B, with ED(50)s ranging from 0.25 to 0.50 mg/kg and 0.11 to 0.29 mg/kg, respectively. These results indicate that FK463 may be a potent parenterally administered therapeutic agent for disseminated candidiasis and aspergillosis.

Problems and solutions of pedicle screw plate fixation of lumbar spine

Fifty-seven patients with low back pain and sciatica of various causes were reviewed with reference to problems associated with pedicle plate fixation of the lumbar spine. Eleven percent of patients had neurologic problems postoperatively and 3.5% (two patients) had severe sensory impairments. All patients had this complication in the early phases of the study. Of 297 screws, 17 broke, ie, 5.7%. These breakages occurred in 12 of 57 patients (21%). In patients with spondylolisthesis, the degree of slip correction averaged 53% postoperatively, which decreased to 35% at the 1-year follow-up. Slip angle was maintained after correction. Pedicle screw plate fixation is an effective form of immobilization of the lumbar spine used in achieving arthrodesis. The surgeon must be fully trained in methodology. It is recommended that screw and plate materials be improved to prevent screw breakage.

Efficacy of FK463, a new lipopeptide antifungal agent, in mouse models of pulmonary aspergillosis

The efficacy of FK463, a novel water-soluble lipopeptide, was evaluated in mouse models of pulmonary aspergillosis and was compared with that of amphotericin B (AMPH-B). In the pulmonary aspergillosis models induced by intranasal inoculation, FK463 exhibited good efficacy, with 50% effective doses in the range of 0. 26 to 0.51 mg/kg of body weight; these values were comparable to those of AMPH-B. In an Aspergillus target organ assay with immunosuppressed mice, under conditions of constant plasma levels of FK463, using a subcutaneously implanted osmotic pressure pump, a significant reduction in viable fungal cells was observed at plasma FK463 levels of 0.55 to 0.80 microgram/ml or higher. We conclude that FK463 is highly effective in the treatment of pulmonary aspergillosis in this animal model. These results indicate that FK463 may be a potent parenterally administered antifungal agent for pulmonary aspergillosis.

Acid hydrolases in leukocytes and platelets of normal subjects and in patients with Gaucher's and Fabry's disease

Lymphocytes, monocytes, neutrophilic granulocytes and platelets were each separated to greater than 95% purity from six normal subjects, three patients with Gaucher's disease, two heterozygotes for Gaucher's disease, and one patient with Fabry's disease. Activities of the following acid hydrolases were determined: "acid" (pH 4.0) beta-glucosidase, pH 5.0 beta-glucosidase, alpha-galactosidase, alpha-arabinosidase, alpha-mannosidase, alpha-glucosidase, beta-glucuronidase, beta-galactosidase, beta-hexosaminidase, and acid phosphatase. Enzymatic activity varied greatly with cell type and the enzyme being measured; the importance of assaying pure preparations especially for heterozygote detection is emphasized. Gaucher's disease patients' cells were found to be deficient in the pH 4.0 acid beta-glucosidase, variable in the pH 5.0 beta-glucosidase, and normal in all other acid hydrolases tested, including acid phosphatase, the activity of which is known to be elevated in plasma. Blood cells of a patient with Fabry's disease were deficient in alpha-galactosidase and normal in all other acid hydrolases tested.

Comparison of ultrasonically activated scalpel versus conventional division for the pancreas in distal pancreatectomy

PURPOSE

The goal of this study was to compare the benefits and complications of using an ultrasonically activated scalpel and conventional division of the pancreas in patients undergoing a distal pancreatectomy.

METHODS

A retrospective review was performed of all patients who underwent distal pancreatectomy at the Department of Surgery, Koshigaya Municipal Hospital. In the ultrasonically activated scalpel (US) group (n = 11), the pancreas was divided using coagulation shears. The stump of the pancreas was left open without parenchymal suturing. In the conventional surgical division (CV) group (n = 20), the pancreas was cut with a knife and the stump was oversewn with interrupted mattress sutures. The main pancreatic duct was ligated in all patients in both groups. The postoperative courses in the two groups were then compared in terms of postoperative serum amylase levels and the incidence of pancreatic fistulas.

RESULTS

The postoperative serum amylase levels were significantly lower in the US group than in the CV group (P < 0.01 on the day of operation). The incidence of pancreatic fistulas was also significantly lower in the US group (0%) than in the CV group (30%) (P = 0.04).

CONCLUSIONS

The use of the ultrasonically activated scalpel was found to reduce the incidence of pancreatic fistula in distal pancreatectomy. Furthermore, the use of this device without any clamping or parenchymal suturing may reduce the damage to the remnant pancreas.

Hepatic resection using the harmonic scalpel

We describe herein our technique of performing extensive resection of the liver by blunt dissection in combination with excision using a harmonic scalpel. A ball coagulator was inserted at 3-cm intervals along the proposed cutting line in the liver, and the liver parenchyma between these holes was then cut using coagulation shears. Regardless of the condition of the liver, good coagulation and cutting were achieved using the harmonic scalpel without vascular occlusion when dividing the shallow layer of the liver, and no complications in association with the harmonic scalpel, such as postoperative bleeding, bile leakage, or abscess formation at the cut margins, occurred. In the deep layer below the main trunk of the hepatic vein, blunt dissection was used, since it was difficult to achieve sufficient control of bleeding from large vessels using the harmonic scalpel alone. Therefore, when used in combination with other techniques, the harmonic scalpel appears to be an effective device for liver surgery that minimizes bleeding and decreases the vascular clamping time.

Acceleration of thrombomodulin gene transcription by retinoic acid: retinoic acid receptors and Sp1 regulate the promoter activity through interactions with two different sequences in the 5'-flanking region of human gene

The interactions between retinoic acid- (RA)-dependent transcriptional regulatory sequences of the 5'-untranslated region of the thrombomodulin gene and nuclear RA-responsive proteins were studied using human pancreas BxPC-3 cells. Deletion mutants of pTM-CAT plasmid revealed the presence of distal and proximal RA-responsive regions containing direct repeat with 4 spaces (DR4) and three of four Sp1 sites, respectively. Cotransfection of a pTM-CAT plasmid with expression plasmids of RA receptors (RARalpha, RARbeta, and RARgamma) augmented the promoter activity under the condition of lower retinoid X receptor-alpha (RXRalpha) expression, whereas the activity was greatly diminished when RXRalpha was highly expressed. An electrophoretic mobility shift assay with cDNA containing the DR4 indicated that heterodimers of RAR and RXRalpha interacted with the DR4 site, although the interaction gradually disappeared with the increase in the ratio of RXRalpha/RAR. On the other hand, Sp1 protein interacted especially with the tandem Sp1 site corresponding to the first and second Sp1 sequences of the four Sp1 sites in the proximal RA-responsive region. The binding of Sp1 to Sp1 sites was independent of RAR-RXR heterodimer but increased with the increase in Sp1 concentration in the presence of unknown factor(s) of reticulocyte lysate. Upon treatment of the cells with RA, time-dependent increases in the ratio of RARbeta to RXRalpha and the phosphorylated form of Sp1 were observed. We concluded that two genomic DNA regions, the DR4 site (-1531 to -1516) and the first and second Sp1-binding sites (-145 to -121), were involved in the RA-dependent augmentation of thrombomodulin gene expression through increased interactions of the two regions with heterodimer of RAR-RXRalpha and nuclear Sp1, respectively.

Follow-up of children after fetal treatment for obstructive uropathy

BACKGROUND

Improvement in the ability to evaluate fetuses with obstructive uropathy, combined with technologic advances, has allowed successful fetal treatment of these conditions in Japan. We analyzed the prenatal and postnatal clinical courses of patients who underwent shunt placement in utero.

METHODS

We treated 6 patients who underwent fetal intervention and were transferred to us for urologic management. Gestational age at detection of abnormalities ranged from 11 weeks to 31 weeks, and fetal intervention was done between 16 weeks and 32 weeks. Excluding 1 infant who was delivered 6 days after the intervention, the mean period between shunt placement and delivery was 17 weeks.

RESULTS

Urologic pathology included prune belly syndrome with urethral hypoplasia in 3 patients, cloacal anomaly in 1, posterior urethral valves in 1, and pelviureteric junction stenosis of a solitary kidney in 1. Four patients required ventilation support in the neonatal period, and 2 of them suffered frequent infections during follow-up. Five patients who underwent vesico-amniotic shunt placement continue to require clean intermittent catheterizations via vesicostomy because of hypoactive detrusors and hypoplastic urethras. After urologic treatment, serum creatinine in 5 patients reached a minimum of less than 0.4 mg/dL at some time during the first year of life. Another patient with a minimum creatinine level of 1.0 mg/dL has moderate renal insufficiency.

CONCLUSION

From our series, it appears that early (before 20 weeks of gestation) shunt placement in severe lower urinary tract obstruction may benefit renal and pulmonary function. However, its efficacy in regard to bladder function remains questionable: shunt placement does not permit regular storage and evacuation, which may be essential for functional bladder development.

Histology of the fetal prune belly syndrome with reference to the efficacy of prenatal decompression

BACKGROUND

Deficient abdominal musculature, complex abnormalities of urinary tracts and bilateral abdominal cryptorchidism represent the basic characteristics of prune belly syndrome (PBS). Although prenatal diagnosis of PBS is rarely made, because of the wide variety of ultrasonographic images, reported cases have gradually increased. Once a fetus suspected of having PBS is found, it is sometimes difficult for the pediatric urologists to decide how to treat them. The histology of the kidney and urinary tracts in fetuses with PBS was reviewed in order to give suggestions on the management of prenatal cases.

METHODS

Autopsy records of nine fetuses (5 males, 2 females and 2 undetermined) with characteristically distended and deficient abdominal wall were reviewed. Gestational age (GA) at detection ranged from 12 to 25 weeks and at delivery from 13 to 32 weeks.

RESULTS

Renal histology in two fetuses showed earlier than normal disappearance of cortical nephrogenic zone replaced by cortical cysts and dysplastic structures. The nephrogenic zone was retained in five fetuses which were younger than GA 20 weeks. While the number of glomeruli along the medullary ray was normal for the age in three fetuses younger than GA 20 weeks, it was decreased in all others. Bladder histology was variable showing both increased musculature and defective or dysplastic muscles. There was a tendency for connective tissues in the bladder wall to increase in proportion to GA, The ureter revealed scarcity of muscle bundles among dense connective tissue. The urethra was atretic in eight fetuses.

CONCLUSION

The clinical implication from the renal histology is that decompression of the urinary tract should be done before GA 20 weeks. However, the early fetal treatment appears to have no effect on the urodynamics in this disorder with deficient musculature.

Urological management of cloacal anomalies

BACKGROUND

A cloacal anomaly results from incomplete urorectal division and is frequently associated with genitourinary abnormalities. Experience of the urological reconstruction of this entity is reported.

METHODS

Nine girls with cloacal malformation have been treated at the Osaka Medical Center in the past 9 years. Seven patients were detected by prenatal ultrasonography as having: megacystis (two patients); hydronephrosis (two patients); or hydrometrocolpos (three patients). Two patients underwent prenatal shunt placement between the enlarged bladder and the amniotic space.

RESULTS

For neonatal urinary diversion, four patients received cystostomy. Six of seven patients with associated hydrocolpos required intermittent catheterization to decompress an enlarged vagina. Vesicoureteral reflux was detected in 12 ureters of seven patients. Antireflux surgery was indicated in four patients before definitive repair. Definitive reconstruction was performed on eight patients. The posterior sagittal approach was used in all patients. Vaginal reconstruction was done utilizing a perineal skin flap (one patient), a tubularized vaginal flap (three patients), distal rectum (three patients) and total urogenital mobilization (one patient). Postoperatively, urethrovaginal fistula was created in one patient and complete occlusion was seen in one patient.

CONCLUSION

The anatomical variety of this entity determines the management options from in utero. It involves not only the creation of three perineal orifices, but also a continent, catheterizable urethra under the stabilization of renal function. Accomplishment of the definitive repair requires the combined expertise of experienced pediatric surgeons and pediatric urologists.

Difference in urinary 11-dehydro TXB2 and LTE4 excretion in patients with rheumatoid arthritis

Thromboxane and leukotrienes have been implicated in inflammation. However, the production level of these eicosanoids in patients with rheumatoid arthritis is still unclarified. In the present study, endogenous synthesis of thromboxane and cysteinyl leukotrienes in patients was investigated. The production of eicosanoids in patients is assessed by measuring stable urinary metabolites,11-dehydro thromboxane B2 and leukotriene E4, using gas chromatography/selected ion monitoring and liquid chromatography/tandem mass spectrometry. The level of urinary thromboxane in patients was significantly higher than that in healthy volunteers (P < 0.05). Furthermore, we investigated the effects of administered drugs on the production of these eicosanoids. The urinary thromboxane level of the untreated group (1630 +/- 613 pg/mg creatinine) was much higher than that of healthy volunteers (342 +/- 263 pg/mg creatinine). The level in the group receiving NSAID alone was similar to that in healthy volunteers, and the group receiving steroid alone showed slightly lower thromboxane levels than the untreated group. On the other hand, the leukotriene E4 level in patients (280 +/- 360 pg/mg creatinine) was also significantly higher than that in healthy volunteers (59 +/- 54 pg/mg creatinine, P < 0.05). In particular, the group receiving methotrexate (904 +/- 685 pg/mg creatinine) had higher leukotriene levels than not only healthy volunteers but also other medicated groups. These findings demonstrated that endogenous thromboxane and leukotriene production in patients with rheumatoid arthritis are enhanced, and the effects of medication on the production of these eicosanoids differed in thromboxane and leukotriene E4.

Animal pharmacokinetics of FK037, a novel parenteral broad-spectrum cephalosporin

Single-dose pharmacokinetics of FK037 has been investigated in laboratory animals. After bolus intravenous dosing with 20 mg/kg, the elimination half-life of FK037 varied in the species; with values of 0.27, 0.30, 0.97, 1.29 and 1.76 hours in mice, rats, rabbits, dogs and monkeys, respectively. The volume of distribution ranged between 260 ml/kg in rats and 390 ml/kg in dogs. These parameters approximated those of ceftazidime and cefpirome used as reference drugs. The renal clearance of FK037 was almost equal to glomerular filtration rate (GFR) in rabbits. Probenecid did not affect the elimination half-life of FK037 and its clearance ratio to GFR. These findings suggest that FK037 is solely excreted by glomerular filtration. FK037 readily penetrated into the tissues and inflammatory exudate fluid in rats, and the tissue level was highest in the kidneys, and decreased in the following order; lungs > heart > liver > spleen. Penetration of FK037, cefpirome and ceftazidime into the cerebrospinal fluid were determined using induced staphylococcal meningitis in rabbits. The penetration percentage ranged from 14.2 to 16.0% for these drugs with no significant differences. The major route of excretion of FK037 was via the kidney, with more than 74% of the dose being excreted in the urine within 24 hours after dosing to each species. Biliary excretion was low, 0.79% in rats. Bioautograms showed only unchanged drug in the plasma, urine and bile. Serum protein binding was low (8.8 to 17.6%) in all the species studied.

Evaluation of serum concentration of parathyroid hormone-related protein and its implication in hypercalcemia in squamous cell carcinoma of the head and neck

Hypercalcemia is a common and serious complication associated with squamous cell carcinoma (SCC) and is considered to be caused by a tumor-derived factor, parathyroid hormone-related protein (PTHrP). However, the correlation between serum levels of calcium and PTHrP and the kinetics of PTHrP in SCC of the head and neck is unknown, because the behavior of the circulating form of PTHrP in patients has not been determined. In the present study, the PTHrP concentrations in serum samples from 54 patients (37 with SCC and 17 with benign tumors) were measured by a recently developed radioimmunoassay directed toward the C-terminal region of PTHrP, and the laboratory data including those calcium levels in corresponding samples were reviewed retrospectively. Results showed hypercalcemia in four patients with advanced cancer and in whom elevation of the serum PTHrP concentration was observed simultaneously. The regression analysis also revealed the linear relationship of the calcium level to the PTHrP concentration, but not to the concentration of phosphorus or creatinine, suggesting that monitoring of serum PTHrP level is useful for prediction of hypercalcemia associated with head and neck cancer.

In vitro antibacterial activity of FK037, a novel parenteral broad-spectrum cephalosporin

FK037 is a new parenteral cephalosporin, which offers some advantages over the commercially available parenteral cephalosporins. It demonstrated potent broad-spectrum activity against clinical isolates of Gram-positive bacteria including methicillin-resistant staphylococci, and Gram-negative bacteria including Pseudomonas aeruginosa. Against clinical isolates of aerobic Gram-positive bacteria, FK037, like cefpirome, demonstrated more potent activity than ceftazidime, cefoperazone and ceftizoxime. It is noteworthy that FK037, on the basis of the MIC90s, was the most active of all the cephalosporins tested against methicillin-resistant Staphylococcus aureus (MRSA). It was similar in activity to cefpirome against methicillin-sensitive S. aureus (MSSA). Against clinical isolates of aerobic Gram-negative bacteria, FK037, like cefpirome, was superior to cefoperazone, similar to ceftazidime and inferior to ceftizoxime in activity. Against P. aeruginosa, FK037 was superior to cefoperazone, similar or slightly superior to cefpirome and inferior to ceftazidime in activity. However, FK037 exhibited significant activity against Citrobacter and Enterobacter which were highly resistant to ceftazidime, cefoperazone and ceftizoxime. FK037 had an advantage in that its bactericidal activity against S. aureus, Escherichia coli and P. aeruginosa at sub-MICs (1/2 or 1/4 the MIC) was much stronger than those of cefpirome and ceftazidime. Moreover, it exhibited potent bactericidal activity against MSSA, MRSA and P. aeruginosa in a pharmacokinetic in vitro model simulating human plasma concentrations after intravenous dosage of 0.125, 1.0 and 1.0 g, respectively. FK037 inhibited essential penicillin-binding proteins (PBPs), 1, 2 and 3 of S. aureus with a 50% inhibitory concentration (I50) of 0.58 micrograms/ml or lower. Of essential PBPs 3, 1a and 1b of E. coli and P. aeruginosa, FK037 inhibited PBP 3 at the lowest I50 (0.03 and 0.04 micrograms/ml, respectively) and PBPs 1a and 1b with I50 values of 2.7 micrograms/ml or lower. FK037, like cefpirome, was highly stable to hydrolysis by various beta-lactamases except Ic cephalosporinase from Bacteroides fragilis, and had extremely low affinity for beta-lactamases. Therefore, FK037 was more potent than ceftazidime in activity against beta-lactamase-producing bacteria except P. aeruginosa and Serratia marcescens. The ability of FK037 to penetrate the outer membrane of E. coli was slightly higher than that of ceftazidime, but slightly lower than that of cefpirome.