Temporal slow waves and cerebrovascular diseases

Sporadic temporal slow waves are considered to be associated with mild cerebrovascular dysfunction. However, electroencephalogram (EEG) changes have not been consistently described by some investigators and correlations inferred on the basis of such data remain inconclusive. In the present study, we examined previously defined temporal slow waves in patients in relation to incidence of cerebrovascular disease. A total of 512 EEG were analyzed during a 1 year period at our laboratory and 74 reference EEG from healthy volunteers were all examined as to the presence of temporal low-voltage irregular delta wave (TLID), temporal minor slow and sharp activity (TMSSA) or bursts of rhythmical temporal theta (BORTT). The patterns were assessed in relation to clinical histories of patients and controls. There were similarities in clinical correlations for the three EEG changes including associations with mild cerebrovascular diseases and with aging. In addition these temporal EEG findings shared electrographic features and showed left side predominance as well as correlating with each other. Since TLID, TMSSA and BORTT have many clinical and electrographical similarities, we consider that these findings should be grouped into one EEG entity which appears in association with mild cerebrovascular dysfunction.

Population pharmacokinetics of tacrolimus in adult recipients receiving living-donor liver transplantation

OBJECTIVE

To characterize the pharmacokinetics of tacrolimus in adult recipients receiving living-donor liver transplantation (LDLT).

METHODS

Thirty-five patients were given tacrolimus as 18- to 60-h intravenous infusions after surgery, followed by a 4-week course of oral dose therapy (at 0900 hours and 2100 hours). Blood samples were collected daily in the morning (0800 hours) beginning the day after surgery. Whole blood concentration data were evaluated by nonlinear mixed-effect modeling using the program NONMEM and were characterized using a one-compartment model.

RESULTS

The clearance (CL, l h(-1)) was related to the grafted hepatic weight, postoperative days (POD), and hepatic and renal dysfunction. Interindividual variabilities in CL, volume of distribution (V), and bioavailability (F) were 57.4%. 39.7%, and 63.0%, respectively, and the correlation between individual CL and F was 0.776. Residual intraindividual variability was 2.9 ng ml(-1). Based on the estimated final parameters, a typical recipient of LDLT with grafted hepatic weight of 600 g and normal hepatic and renal function would have a CL of 0.737 l h(-1) on POD 0 and 1.14 l h(-1) on POD 30, V of 1.52 l kg(-1) and F of 6.8%.

CONCLUSIONS

Nonlinear mixed-effect modeling was useful for analysis of pharmacokinetic characteristics of tacrolimus in LDLT patients. Immediately after surgery, patients receiving LDLT showed a smaller CL value than other transplant patients, and CL value increased with POD within 30 days after surgery. The estimated population pharmacokinetic parameters can be applied for a priori dosage calculations in adult patients with LDLT.

Role of kidney-specific organic anion transporters in the urinary excretion of methotrexate

BACKGROUND

High-dose folinic acid is used to accelerate methotrexate elimination to avoid renal toxicity of the drug. The present study was carried out to examine the role of the renal organic anion transporters OAT-K1 and OAT-K2 in the urinary excretion of methotrexate, especially in the methotrexate-folinic acid rescue therapy.

METHODS

Madin-Darby canine kidney cells stably expressing OAT-K1 and OAT-K2 were used for the in vitro transport study; 5/6 nephrectomized rats were used to detect changes in mRNA expression levels of OAT-K1 and OAT-K2 and to evaluate methotrexate pharmacokinetics under conditions of renal insufficiency.

RESULTS

Methotrexate efflux mediated by these transporters in stable transfectants was stimulated in the presence of extracellular folic acid and folinic acid, suggesting that they could serve as anion exchangers to enhance the apical efflux of methotrexate. The mRNA expression levels of OAT-K1 and OAT-K2 were markedly diminished after 5/6 nephrectomy, but those of multidrug resistance associated protein 2, which could transport methotrexate, were maintained. Renal clearance of methotrexate was markedly decreased in 5/6 nephrectomized rats compared with that in sham-operated rats. Additional folinic acid treatment resulted in a significant increase in methotrexate renal clearance in sham-operated rats but not in 5/6 nephrectomized rats.

CONCLUSIONS

The decreased expressions of OAT-K1 and OAT-K2 may be attributable to the longer exposure to methotrexate and ineffective folinic acid rescue. In terms of contributing to patient safety, renal clearance of methotrexate, especially folinic acid-stimulated tubular secretion of the drug via these transporters, would be a key factor in methotrexate therapy.

Fluorescence in situ hybridization analysis of peripheral blood cells in Pearson marrow-pancreas syndrome

We used a dual-color fluorescence in situ hybridization technique to estimate deleted mitochondrial DNA at a single-cell level and determine any correlation with the disease progression in lymphocytes from patients with Pearson marrow-pancreas syndrome. The method demonstrated a shift in heteroplasmy, paralleling the hematologic improvement.

Acquisition of the monocyte/macrophage phenotype in human mesangial cells

The function of intrinsic glomerular cells in active glomerular inflammation may be similar to that of monocytes/macrophages. Mesangial cells have phagocytic properties and release numerous mediators. In this study we examined whether human mesangial cells (hMCs) express a monocyte/macrophage phenotype in active glomerular inflammation. We report that the proto-oncogene c-fms, the macrophage colony-stimulating factor (M-CSF) receptor, which is a characteristic gene of monocytes/macrophages, is expressed in hMCs. Normal unmanipulated hMCs express weak c-fms mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR), and its expression increases after stimulation with platelet-derived growth factor-BB (PDGF-BB) and epidermal growth factor (EGF). The expression of c-fms was also demonstrated by flow cytometry with a specific polyclonal antibody. By immunohistochemistry, c-fms was prominently detected in acute glomerulonephritis, IgA nephritis, and lupus nephritis. These results indicate that hMCs express c-fms in active glomerular inflammation and are consistent with mesangial cells acquiring some macrophage-like characteristics in diseased states.

Recognition and transport characteristics of nonpeptidic compounds by basolateral peptide transporter in Caco-2 cells

Recent studies have revealed that diverse compounds lacking peptide bonds, such as valacyclovir and delta-aminolevulinic acid (delta-ALA), can be recognized by H+-coupled peptide transporters (PEPT1 and PEPT2). In the present study, recognition and transport characteristics of nonpeptidic compounds by the basolateral peptide transporter, which is distinct from PEPTs, were compared with those by PEPT1 using the human intestinal Caco-2 cells. [14C]Glycylsarcosine uptake via PEPT1 was inhibited by all nonpeptidic compounds tested. Similarly, most nonpeptidic compounds showed an inhibitory effect on [14C]glycylsarcosine uptake by the basolateral peptide transporter, although some kinds of nonpeptidic compounds, such as valine methyl ester, did not. Direct measurements of valacyclovir and delta-ALA transport revealed that both compounds were able to be transported by the basolateral peptide transporter. Because delta-ALA has been used recently in vitro and in clinical studies as an endogenous photosensitizer for photodynamic therapy, the intestinal transport characteristics of delta-ALA were further examined. Inhibition studies and Eadie-Hofstee plot analysis suggested that delta-ALA transport across the brush-border and basolateral membranes of the intestine was mainly mediated by peptide transporters. In addition, the apical-to-basolateral transport of delta-ALA was greater than that of the opposite direction. These findings provide the first evidence that the intestinal basolateral peptide transporter can recognize and transport nonpeptidic compounds, and play a definitive role in the absorption of delta-ALA.

A case of repetitive intrapleural cancer chemotherapy using INFUSE-A-PORT for malignant mesothelioma

A 57-year-old man was diagnosed as having malignant pleural mesothelioma. We placed an implantable reservoir (INFUSE-A-PORT) into his pleural cavity to administer repetitive intrapleural chemotherapy. We administered intrapleural chemotherapy 7 times over a period of 10 months. The progression of the disease was very gradual; he could continue working during this time. INFUSE-A-PORT may be useful for repetitive intrapleural chemotherapy in outpatient treatment of malignant mesothelioma.

EUS-guided one-step drainage of pancreatic pseudocysts: experience in 3 patients

BACKGROUND

EUS-guided drainage has been recognized as a nonsurgical treatment for pancreatic pseudocysts. Bleeding at the puncture site is a known complication of this procedure. This is a report of the use of new equipment for one-step drainage without the use of an electrosurgical needle.

METHODS

EUS-guided cystoenterostomy was performed in 3 patients. The mean size of the pseudocysts was 8 cm (head = 1, body = 2). A needle and drainage tube were inserted in a one-step procedure into the cyst through the accessory channel of an echoendoscope under EUS. The drainage tube was released immediately after insertion.

OBSERVATIONS

All 3 patients were treated successfully without complication. A drainage tube was inserted through the duodenal bulb (n = l) and the body of the stomach (n = 2). The drain was removed after 1 month in all patients. Two of the 3 drains were obstructed by sludge. One pseudocyst recurrence was observed at a mean follow-up of 3.6 months (range 2-6 months).

CONCLUSIONS

The EUS-guided one-step system is simple to use and suitable for drainage of pancreatic pseudocysts. It appears to minimize the risk of hemorrhage.

[Therapeutic drug monitoring of immunosuppresants]

The pharmacokinetics and pharmacodynamics of tacrolimus were evaluated in the pediatric recipients of living-related liver transplant. The mean clearance for tacrolimus was estimated with large interindividual variability and was shown to change as a function of days after operation. The therapeutic blood concentration of tacrolimus ranges were concerned from nearly 10 to 20 ng/ml. We have examined whether the expression levels of the intestinal absorptive barriers, MDR1 gene product P-glycoprotein and cytochrome P450 IIIA4(CYP3A4), correlate with the trough levels of orally administered tacrolimus in a recipient of small bowel transplant for 4 months. Both the MDR1 and CYP3A4 mRNA levels changed markedly through out this period. The tacrolimus concentration/dose ratio correlated well with the mRNA expression level of MDR1, but not CYP3A4. Intestinal P-glycoprotein rather than CYP3A4 is a good probe to predict the intraindividual variation in the tacrolimus pharmacokinetics.

Mutational analysis of MECP2 in Japanese patients with atypical Rett syndrome

Rett syndrome (RTT) is one of the most common neurodevelopmental disorders in females. Recently, this disease was found to be linked with mutations in the methyl-CpG-binding protein 2 gene (MECP2) and various mutations have been reported. To explore the spectrum of phenotypes resulting from MECP2 mutations, we searched for mutations in the MECP2 of 20 Japanese patients who had more than five of the criteria necessary for RTT diagnosis proposed in 1988 (The Rett Syndrome Diagnostic Criteria Work Group, Ann Neurol 23 (1988) 425) and compared the phenotype between patients with and without mutation by giving a score to each diagnostic criterion. We found four missense mutations (T158M, R133C, Y120D, and R306C), two nonsense mutations (R168X and R270X), one frameshift (726delAAAG) mutation, and one polymorphism (A201V) in ten patients (50%). This included two novel mutations (726delAAAG and Y120D). All mutations were found in the highly conserved methyl-binding and transcription repression domains. Comparison of the mean total diagnostic criterion score of the groups with and without mutation did not reveal any statistically significantly difference (P=0.28). The only difference between the groups, which was of borderline significance (P=0.051), was the sum of the scores for diagnostic criteria 2 (apparently normal psychomotor development through the first 6 months) and 5 (loss of acquired purposeful hand skills between the ages of 6 and 30 months). From these results, it is suggested that the clinical phenotype of RTT is variable and it is important to investigate the MECP2 genotype for patients having more than five criteria and not only in those who exhibit all RTT diagnostic criteria. The diagnosis of RTT is clinically difficult before 3 years of age, especially in atypical cases, but molecular analysis of the MECP2 will assist diagnosis in some patients.

Prognostic factors in patients with resected pathologic (p-) T1-2N1M0 non-small cell lung cancer (NSCLC)

OBJECTIVES

To clarify prognostic factors in resected pathologic (p-) T1-2N1M0 non-small cell lung cancer (NSCLC).

METHODS

A total of 95 consecutive patients who underwent complete tumor resection and mediastinal dissection for pT1-2N1M0 NSCLC between 1976 and 1997 were retrospectively reviewed. p53 status and proliferative activity were evaluated immunohistochemically.

RESULTS

The extent of N1 stations and p53 status proved to be significant prognostic factors. The 5-year survival rate for tumor without hilar node (#10) involvement was 66%, significantly higher than that for tumor with #10 involvement (39%, P<0.01). The 5-year survival rate for tumor with aberrant p53 expression was 37%, significantly lower than that for tumor without aberrant p53 expression (74%, P<0.01). There proved to be no significant difference in the prognosis between pT1 disease and pT2 disease; the 5-year survival rates for pT1 and pT2 diseases were 62 and 56%, respectively. Age, gender, performance status, grade of tumor differentiation, histological type, or proliferative activity were not significant factors. Multivariate analysis of prognostic factors using Cox's proportional hazard model confirmed these results.

CONCLUSIONS

Involvement of the hilar node and aberrant p53 expression were significant factors to predict a worse prognosis in resected T1-2N1M0 NSCLC.

Rinderpest virus (RPV) ISCOM vaccine induces protection in cattle against virulent RPV challenge

Rinderpest virus (RPV), a member of genus Morbillivirus in the family Paramyxoviridae, causes an acute and often fatal disease in cattle and other large ruminants. A subunit rinderpest vaccine consisting of an immune-stimulating complex (ISCOM) incorporating the RPV haemaggulutinin (H) protein, was examined for its ability to induce protective immunity in cattle, the natural host of RPV. All of four cattle vaccinated with the ISCOM vaccine survived challenge with virulent virus. Three were solidly protected, showing no clinical signs of infection, while the fourth animal developed only mild and transient symptoms. Virus neutralizing antibodies were produced at a significant level in all vaccinated cattle. These results indicate that this ISCOM vaccine is effective in producing protective immunity in cattle and should be a suitable means of delivering glycoprotein antigens from other morbilliviruses.

Transport of levofloxacin in the OK kidney epithelial cell line: interaction with p-aminohippurate transport

PURPOSE

To evaluate the mechanism of renal transport of quinolone antibacterial drugs, we examined the interaction of levofloxacin with p-aminohippurate (PAH) transport systems and the transport of levofloxacin in renal epithelial cells.

METHODS

Transport of [14C]PAH or [14C]levofloxacin was measured using OK cell monolayers grown on microporous membrane filters.

RESULTS

Transcellular transport from the basolateral to the apical side and cellular accumulation of [14C]PAH were inhibited by levofloxacin. Both the initial uptake of [14C]PAH from the basolateral side and the efflux to the apical side were inhibited by levofloxacin. The basolateral-to-apical transcellular transport of [14C]levofloxacin was greater than that in the opposite direction. [14C]Levofloxacin efflux to the apical side was greater than that to the basolateral side. Unlabeled levofloxacin and grepafloxacin inhibited the transcellular transport of [14C]levofloxacin, accompanied by an increase of cellular accumulation. However, neither PAH nor an anion transport inhibitor 4-4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) affected the basolateral-to-apical transport of [14C]levofloxacin nor its uptake from the basolateral side.

CONCLUSIONS

These results indicated that levofloxacin inhibits PAH transport across both the basolateral and apical membranes of OK cells, but are not transported via the systems for PAH transport. The existence of a specific transport system for quinolones was indicated in OK cells.

Physiological and pharmacological implications of peptide transporters, PEPT1 and PEPT2

The H+/peptide co-transporters PEPT1 and PEPT2 mediate the cellular uptake of small peptides and peptide-like drugs from the glomerular filtrates. In the present study, we investigated the physiological and pharmacological implications of both transporters. (i) Comparison of the substrate affinity of PEPT1 and PEPT2 indicated that PEPT2 had higher affinity than PEPT1 for most substrates. (ii) The transport characteristics of beta-lactam antibiotics in the renal brush border membrane vesicles were well correlated with those in a PEPT2-expressing transfectant. These results suggested that PEPT2 predominantly contributed to reabsorption of beta-lactam antibiotics in the kidney at therapeutic concentrations. (iii) In rats with chronic renal failure, glycylsarcosine (Gly-Sar) uptake by the renal brush border membranes vesicles was maintained, whereas Na+-dependent glucose uptake was markedly reduced. It is therefore speculated that the function of peptide transporters is tolerant to chronic renal failure.

Prognostic significance of polysialic acid expression in resected non-small cell lung cancer

Polysialic acid (PSA) is a carbohydrate attached mainly to the neural cell adhesion molecule. Because PSA is composed of a linear homopolymer of alpha-2-8-linked sialic acid residues and has a large negative charge, the presence of PSA attenuates the adhesive property of neural cell adhesion molecule and increases cellular motility. In an earlier study, we demonstrated that PSA and STX, a polysialyltransferase, were associated with tumor progression in non-small cell lung cancer (NSCLC) (F. Tanaka et al., Cancer Res., 60: 3072-3080, 2000). Therefore, in the present study, to assess the prognostic significance of PSA in resected NSCLC, a total of 236 patients who underwent complete resection for pathological (p)-stage I-IIIa disease were reviewed retrospectively. PSA was expressed in 44 of 236 (18.6%) patients, and the expression was correlated with p-stage disease. For all p-stage patients, 5-year survival rates for those with PSA-positive and PSA-negative tumors were 52.1% and 71.3%, respectively, demonstrating a significantly worse prognosis for the PSA-positive patients (P = 0.012). Analysis for only p-stage I patients also demonstrated a significantly worse prognosis for the PSA-positive patients; 5-year survival rates of the PSA-positive and the PSA-negative patients were 45.1% and 83.5%, respectively, (P < 0.001). In addition, there proved to be no difference in the postoperative survival among p-stage I, II, and IIIa patients when PSA expression was positive. Multivariate analysis confirmed that PSA expression was an independent factor to predict poor prognosis in resected NSCLC. These results suggested that PSA could be an important clinical marker and that preoperative induction and/or postoperative adjuvant therapies should be performed for PSA-positive NSCLC, even if the disease is classified as p-stage I.

A new variant neuropathic type of Gaucher's disease characterized by hydrocephalus, corneal opacities, deformed toes, and fibrous thickening of spleen and liver capsules

We report a new variant type of Gaucher's disease characterized by hydrocephalus, corneal opacities, deformed toes, gastroesophageal reflux, and fibrous thickening of splenic and hepatic capsules. This patient had 1 D409H allele. He differed from other reported cases with a 1342G to C (D409H) homozygous mutation (onset at 4 months, no cardiac involvement until the age of 12 years, and massive hepatosplenomegaly with fibrous thickening of spleen and liver capsules). Enzyme replacement therapy was given for 4 years, resulting in an improvement of visceral and hematologic abnormalities but no neurologic improvement.

Apoptosis and p53 status predict the efficacy of postoperative administration of UFT in non-small cell lung cancer

To examine whether efficacy of postoperative oral administration of UFT, a 5-fluorouracil derivative chemotherapeutic agent, may be influenced by incidence of apoptosis (apoptosis index) or apoptosis-related gene status (p53 and bcl-2) of the tumour, a total of 162 patients with pathologic stage I non-small cell lung cancer were retrospectively reviewed. UFT was administrated postoperatively to 44 patients (UFT group), and not to the other 118 patients (Control group). For all patients, 5-year survival rate of the UFT group (79.9%) seemed higher than that of the Control group (69.8%), although without significant difference (P = 0.054). For patients with higher apoptotic index, 5-year survival rate of the UFT group (83.3%) was significantly higher than that of the Control group (67.6%, P = 0.039); for patients with lower apoptotic index, however, there was no difference in the prognosis between these two groups. Similarly, UFT was effective for patients without p53 aberrant expression (5-year survival rates: 95.2% for the UFT group and 74.3% for the Control group, P = 0.022), whereas not effective for patients with p53 aberrant expression. Bcl-2 status did not influence the efficacy of UFT. In conclusion, apoptotic index and p53 status are useful factors to predict the efficacy of postoperative adjuvant therapy using UFT.

SSCP analysis by RT-PCR for the prenatal diagnosis of Niemann-Pick disease type C

The molecular prenatal diagnosis of Niemann-Pick disease type C (NPC) is presented. The proband with a late infantile type of NPC was a compound heterozygote of a paternal missense mutation, T529G, and a maternal 2 bp deletion at nt 350 of the NPC1 gene. These mutations were detected by single-strand conformation polymorphism (SSCP) analysis of RT-PCR products. When the proband was aged 4 years 3 months, prenatal diagnosis for the second child was performed using both biochemical and molecular methods. SSCP analysis for the parental mutations using cDNA from cultured amniotic fluid cells revealed the absence of both mutations and the fetus was diagnosed as being unaffected. This diagnosis was supported by a normal level of cholesterol esterification using cultured amniotic fluid cells. After the child's birth, when he was 21 months old, the diagnosis was confirmed by SSCP analysis of genomic DNAs of his family. This analysis also revealed a unique variation of intron 13, IVS13+753-758 del TTTTTT, that was shared only by the proband and the father, and was suspected as being linked to the T529G missense mutation. A combination of both biochemical and molecular analyses is very useful and reliable for prenatal diagnosis of Niemann-Pick disease type C.

Inhibitory mechanism by polysialic acid for lamina-specific branch formation of thalamocortical axons

During development, thalamocortical axons form arbors primarily in layer 4 of the neocortex. This lamina-specific branch formation was studied in cultures of rat thalamic explants grown next to chemically fixed cortical slices. After a week in vitro, thalamic axons formed branches specifically in the target layer of fixed cortical slices, regardless of the orientation of the ingrowth. This in vitro system permits a direct assessment of contributions of membrane-associated molecules to thalamic axon branch formation. To this end, the present study uses three enzymatic perturbations: chondroitinase, phosphatidylinositol phospholipase C, or the polysialic acid (PSA)-specific endoneuraminidase (endo N). With endo N pretreatment of cortex, the number of branch points was increased significantly, whereas branch tip length was decreased. In addition, the localization of branch points to the target layer was weakened considerably. These features of branch formation were not altered by the other two enzymatic treatments, except that branch tips were shortened by chondroitinase treatment to the same extent as in endo N treatment. These results suggest that membrane-bound components are involved in lamina-specific branch formation of thalamocortical axons, and in particular that PSA moieties contribute to laminar specificity by inhibiting branch emergence in inappropriate layers.