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The evolution of gamma-secretase modulators (GSMs) through the introduction of novel heterocycles with the goal of aligning activity for reducing the levels of Aβ42 and properties consistent with a drug-like molecule are described. The insertion of a methoxypyridine motif within the tetracyclic scaffold provided compounds with improved activity for arresting Aβ42 production as well as improved properties, including solubility. In vivo pharmacokinetic analysis demonstrated that several compounds within the novel series were capable of crossing the BBB and accessing the therapeutic target. Treatment with methoxypyridine-derived compound 64 reduced Aβ42 levels in the plasma of J20 mice, in addition to reducing Aβ42 levels in the plasma and brain of Tg2576 mice.

Summary Purpose (1) To identify bone-shape changes from baseline to 3-years after anterior cruciate ligament reconstruction (ACLR). (2) to assess association between changes in bone-shape from baseline to 6-months and changes in cartilage matrix and patient functions and symptoms from baseline to 3-years after ACLR. Methods Bilateral knees of 30 patients with unilateral ACL injuries were scanned at baseline, 6-months, 1-, 2-, and 3-years after ACLR. Bilateral knees of 13 controls were scanned at baseline, 1- and 3-years. Mean T1ρ and T2 values of each cartilage compartment were computed. Bone shape was quantified using statistical shape modeling (SSM) and 3D-MRI. Patient functions and symptoms were evaluated using Knee Injury and Osteoarthritis Outcome Score (KOOS). Results Statistically significant changes were observed in Femur 2 (medial femoral condyle [MF] shape), Femur 6 (intercondylar notch width), Tibia 1 (tibia plateau area), and Tibia 7 (medial tibia slope) over 3-years after ACLR. Statistically significant differences were observed between injured and control knees in several modes. Statistically significant correlations were found between changes in bone shape (ΔFemur 6, ΔFemur 8 [trochlea inclination and MF height], ΔTibia 1) from baseline to 6-months and that of cartilage T1ρ and T2 and KOOS from baseline to 3-years after ACLR. Conclusion Bone shape remodeling occurs after ACLR, and early bone shape changes (within 6 months) correlated with cartilage matrix and patient outcomes at 3-years after ACLR. Bone shape can be a promising imaging biomarker that stratifies patients at high risk for post-traumatic osteoarthritis (PTOA).

Summary Objective To estimate the burden of knee osteoarthritis (OA) among Chinese population. Design Individuals with symptomatic knee OA based on self-reported physician-diagnosed arthritis and presence of knee pain were identified in China Health and Retirement Longitudinal Study. Severity of knee OA was divided into three categories: mild, moderate and severe, according to knee pain severity. We estimated sex-specific years lived with disability (YLD) and YLD rate (per 100,000 population) by multiplying the prevalence of knee OA with appropriate disability weight (DW) and examined associations between several key sociodemographic factors and YLDs. Results Among 17,459 subjects (52.1% women; mean age 59.1 years) included in this analysis, prevalence of mild, moderate and severe knee OA was 1.5%, 3.3%, and 3.9%, respectively. The total number of YLDs for knee OA in China was 4,149,628, and YLDs per 100,000 population was 968. Female sex, older age, rurality, lower education, and lower gross domestic production (GDP) per capita were associated with high YLDs rates for knee OA, respectively. The North and East regions of China had the lowest YLD rate per 100,000 population for knee OA (631 and 699), followed by South-central (858), Northeast (878), and Northwest (1502) regions. Southwest region had the highest YLD rate from knee OA (1653). Conclusions In this nationally representative sample, we demonstrated a high burden from knee OA among Chinese population. YLD rate for knee OA varied significantly according to sociodemographic factors. Our study calls for an urgent need for health policy support and cost-effective preventive strategies in China.

In this study, we identified potential serum biomarkers for the diagnosis of active tuberculosis (TB) and screening for latent TB infections (LTBIs). Peripheral blood samples from 40 healthy individuals, 40 patients with TB, and 40 LTBI individuals were stimulated with the TB-specific antigens ESAT-6 and CFP-10. Human inflammatory cytokine arrays were used to detect the expression of inflammatory cytokines. Cytokines with significant changes were screened to construct a cytokine regulation network. The levels of the cytokines CCL1 (I-309), CXCL9 (MIG), IL-10, IL-6, CSF2, CSF3, IL-8, IL-1α, IL-7, TGF-β1, CCL2, IL-2, IL-13, and TNFα were significantly upregulated in the active TB group. The levels of CCL3, IL-1β, CCL8, IFNγ, and CXCL10 were significantly increased in the TB groups compared to those in the healthy control group. sTNF RII was upregulated in the LTBI group. CCL4 and MIP1d were significantly increased in all groups.The upregulated cytokines were mainly found in the IFNγ and IL-1α regulatory networks. Importantly, we found that CXCL10 (IP-10), CCL3, CCL8, and IL-1β may be more suitable than IFNγ for active or latent TB infection screening. Furthermore, we found that levels of CCL1 (I-309), CXCL9 (MIG), IL-10, IL-6, CSF2, CSF3, IL-8, IL-1α, IL-7, TGF-β1, CCL2, IL-2, and IL-13 after TB antigen stimulation may help distinguish between active and latent TB.

The clinical diagnosis of snakebites is critical and necessary in many parts of the world, especially in Southeastern Asia, where venomous snakebites are a burden on public health. It is difficult to define or recognize the species of venomous snake because of the overlapping clinical manifestations of envenomations. A quick and reliable method for identifying the snake species is necessary. We designed and tested a strip of lateral flow system for the diagnosis of cobra snake bites in Taiwan.We developed a kit based on an immunochromatographic method for rapid detection of cobra (Naja atra) venom in human serum. The test and control lines composed of 1 mg/ml polyclonal duck antivenom and 0.5 mg/ml goat anti-rabbit immunoglobulin antibody solutions, respectively, were coated on nitrocellulose strips. Colloidal gold was conjugated with rabbit polyclonal anti-cobra venom antibodies. From July 2007 to December 2012, we used the kit to test serum from snakebite patients and to examine the agreement between our rapid test and the currently used sandwich enzyme-linked immunosorbent assay (ELISA).Our kit was able to detect cobra venom in serum samples in 20 minutes with a detection limit of 5 ng/ml. An absence of cross-reactivity with other non-cobra venoms from Taiwan was noted in vitro. A total of 88 snakebite patients (34 cobra and 54 other non-cobra) were tested. The sensitivity of the strips based on the ELISA results was 83.3% and the specificity was 100%. There was a strong agreement between the results of the ELISA and immunochromatographic strips (κ = 0.868).This data indicates that an immunochromatographic strip might be suitable for cobra venom detection and could be used as a quick diagnostic tool in cases of N. atra snakebite.

A cDNA microarray-assisted experiment was conducted to survey genes that respond early to heat shock in enriched immature porcine germ cells; the 5′-UTR flanking the highest upregulated gene, heat shock 105/110 kDa protein 1 ( Hsph1 or Hsp105 ), in response to heat shock was also investigated. We established a porcine testis cDNA microarray with 9944 transcripts from two libraries constructed from the testes of mature boars, with or without heat shock. After a mild heat shock treatment (39 °C for 1 h and recovered at 34 °C for 2 h), 380 transcripts demonstrated significant gene expression in enriched immature germ cells; 326 were upregulated and 54 were downregulated. Ten transcripts of interest exhibiting significance analysis of microarrays (SAM) scores higher than the median were subjected to quantitative real-time PCR; three ( Hsp105 , Hspa4l and Thap4 ) were upregulated >1.5-fold. The sequence of the 5′-UTR of Hsp105 , the highest upregulated transcript, was cloned and analyzed. A single nucleotide polymorphism (SNP) was found at position −762 (C or T) upstream of the translational start site (ATG codon). Only two genotypes (CC or TC) were found in the mature boars that were studied ( n = 31). A heterozygous genotype (TC) at this SNP site revealed an elevated percentage of morphologically normal sperm during hot and cold seasons; this SNP may be a useful marker for semen quality in boars. Furthermore, the cell-model established from enriched primitive germ cells has potential for the study of reproduction in mature animals.

1. The disposition of 3-[2-oxo-3-[3-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl) propyl]-imidazolidin-1-yl]-3(S)-(6-methoxy-pyridin-3-yl)propionic acid (compound A), a potent and selective alpha(v)beta(3) antagonist, was characterized in several animal species in support of its selection for preclinical safety studies and potential clinical development. 2. Compound A exhibited marked species differences in pharmacokinetics; the plasma clearances and bioavailabilities ranged from 33-47 ml min(-1) kg(-1) in rats and mice to 4-9 ml min(-1) kg(-1) in dogs and monkeys, and about 20% in rats to 70-80% in dogs and monkeys, respectively. Both the intravenous (i.v.) and oral kinetics of compound A were linear over the dose range studied in dogs (0.1-5 mg kg(-1) i.v. and 0.25-20 mg kg(-1) orally [p.o.]) and rats (1-30 mg kg(-1) i.v. and 4-160 mg kg(-1) p.o.). 3. Compound A was eliminated substantially by urinary excretion; the urinary recovery of the unchanged drug was 67% in rhesus, 48% in dogs and about 30% in rats. In these animal species, biotransformation was modest. 4. Following i.v. administration of [(14)C]-compound A to rats, the radioactivity rapidly distributed to all tissues investigated, with high levels of the radioactivity detected in liver, kidney and intestine soon after the drug administration. The radioactivity declined rapidly, with less than 1% of the i.v. dose remaining at 30-h post-dose. 5. Compound A was moderately bound to plasma proteins, with unbound fractions of 26, 20, 14 and 5% for rats, dogs, monkeys and humans, respectively. It was bound primarily to human alpha(1)-acid glycoprotein (about 85% binding at 0.1% concentration), as compared with human albumin (50% binding at 4% concentration). 6. Using simple allometry, compound A was predicted to exhibit relatively low clearance (1-3 ml min(-1) kg(-1)) and low volume of distribution (0.1-0.3 l kg(-1)) in humans. Based on the predicted values, compound A was projected to exhibit a favourable oral pharmacokinetic profile in humans, with good bioavailability (50-80%). These predicted values provided a basis for compound selection for further development.

1. The study investigated mechanisms underlying the stereoselective hepatic disposition observed in rats of a zwitterionic diastereomeric pair ((3S)-3-[(3R or 3S)-2-oxo-3-[3-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl)propyl]pyrrolidin-1-yl]-3-quinolin-3-ylpropanoic acid) with different lipophilicities. 2. In a recirculating isolated rat liver system, the more hydrophilic diastereomer II possessed biliary clearance, CLb, and bile-to-liver concentration ratio higher (about 10-30-fold) than the lipophilic zwitterion I, whereas both I and II exhibited comparably high concentration ratios between liver and perfusate. Although MK-571, a known multidrug resistance protein (MRP) inhibitor, significantly inhibited the CLb of both compounds, it did not inhibit their canalicular transport, as evident by unchanged concentration ratios between bile and liver of either I or II. 3. Following an intravenous infusion of I or II to Sprague-Dawley rats, the biliary clearance calculated either based on plasma (CL(b,p)) or liver concentration (CL(b,l)), of II was much higher than that of I (about 5-50-fold). In rats lacking multidrug resistance protein 2 (Mrp2) (Eisai hyperbilirubinemic rat, EHBR), the biliary excretion rate and CL(b,p) of II were also higher than the corresponding values for I. However, both CL(b,p) or CL(b,l) of either I or II were not reduced in EHBR, as compared with control SD rats. 4. In the in vitro rat canalicular membrane vesicle study, I and II exhibited no differences in their inhibitory effect on the Mrp2 mediated ATP-dependent [3H]DNP-SG initial uptake (no inhibition at 10 microM and only about 40% inhibition at 100 microM). 5. Collectively, these results suggested that (1) the difference in the hepatic disposition between the two isomers was due primarily to the difference in their transport mechanism across the canalicular membrane and (2) Mrp2 did not play a major role in the observed differences in the biliary excretion of the diastereomers I and II in rats.

To investigate prospectively the frequency and clinical determinants of poststroke dementia (PSD) in a cohort of consecutive ischemic stroke inpatients in southern Taiwan.A standard stroke evaluation protocol was conducted at admission and 3 months after an ischemic stroke. The protocol included clinical, neurologic, neurobehavioral, and functional assessments as well as neuroimaging examinations. Diagnoses were made according to the Neurologic Adaptation of the 10th edition of the International Classification of Diseases criteria for dementia.Excluding patients with prestroke dementia, a total of 283 patients were surveyed at 3 months after stroke; 26 (9.2%) of them met the criteria for PSD. The correlates of PSD in logistic regression analyses were age 65 years or older (odds ratio [OR] 6.6) vs65 years, previous occupation as a laborer (OR 3.3), prior stroke (OR 3.1), left carotid vascular territory (OR 12.5) vs vertebrobasilar and unknown territories, moderate to severe stroke severity (OR 3.4), and cognitive impairment (OR 4.5) and poorer functional status at admission (OR 4.5). Based on the significant predictors identified, the logistic regression model correctly classified PSD in 93.4% of subjects.The lower frequency of PSD in this study from Taiwan compared with previous studies from Western countries may have been due to the relatively younger age of the elderly population and the use of stricter diagnostic criteria.

1. The use of a beneficial interaction between indinavir and compound A, a potent investigational HIV protease inhibitor to enhance systemic exposure of compound A, was investigated. 2. When administrated alone, compound A underwent extensive hepatic first-pass metabolism in rats and monkeys, resulting in low oral bioavailability. 3. In vitro studies with liver microsomes revealed that compound A metabolism was mediated exclusively by CYP3A enzymes in rats, dogs and monkeys. Indinavir, which also was metabolized predominantly by CYP3A enzymes, extensively inhibited compound A metabolism in microsomes, whereas compound A showed weak inhibitory potency on indinavir metabolism. 4. Consistent with in vitro observations, co-administration of the two compounds resulted in a 17-fold increase in oral AUC of compound A in rats owing to the inhibition of metabolism of compound A by indinavir, whereas compound A did not affect indinavir metabolism as indicated by the unchanged indinavir AUC. Similarly, the systemic exposure of compound A in dogs and monkeys was increased substantially following oral co-administration with indinavir by 7- and > 50-fold, respectively. 5. Enhancement in compound A systemic exposure by indinavir in humans, as predicted based on the in vivo animal and in vitro human liver microsomal data, was confirmed in subsequent clinical studies.

A study was conducted to examine the tolerability and pharmacokinetics of single and multiple oral doses of L-365,260, a novel antagonist for type B cholecystokinin (CCK) receptors and to quantify effects of selective blockade of type B CCK receptors through treatment with L-365,260 on measures of anxiety, hunger, and cognitive performance. Healthy volunteers were given single oral doses of up to 50 mg of L-365,260 and multiple oral doses of up to 25 mg every 6 hours for 10 days. Plasma concentrations of L-365,260 were quantified by means of high-performance liquid chromatography. Anxiety and hunger were assessed by visual analog scale and the Spielberger State Anxiety Index. Cognitive testing was used to evaluate attention level and short-term memory. L-365,260 was rapidly absorbed and a biphasic pattern of elimination was demonstrated with a terminal half-life (t 1/2 ) of 8 to 12 hours. The mean (n = 6) values for peak plasma concentration (C max ) and time to peak concentration (t max ) of L-365,260 were 503 ng/mL and 1.25 hours, respectively, after a single 50-mg oral dose. Accumulation of L-365,260 plasma concentrations was seen after the prescribed multiple-dose regimens. Steady state was achieved after 3 days of oral administration. L-365,260 had an acceptable tolerability profile after oral administration. No changes in measures of anxiety, hunger, or short-term memory were observed at doses of L-365,260 shown to have antagonist activity at the CCK-B receptor.

The purpose of this study was to examine the psychometric properties of the Chinese version of Cerebral Palsy Quality of Life for Children (CP QOL-Child) questionnaire. We performed forward (into Chinese) and backward translation of the CP QOL-Child for: (1) the primary caregiver form (for parents of children with CP aged 4-12 years); and (2) the child self-report form (for children with cerebral palsy aged 9-12 years). Psychometric properties assessed included test-retest reliability, internal consistency, item discrimination, construct validity, and concordance between the forms of questionnaire. The Chinese CP QOL-Child was completed by 145 caregivers and 44 children. Excellent test-retest reliability and internal consistency were obtained. Item discrimination analysis revealed a majority of the items have moderate to good discriminating power. Confirmatory factor analysis demonstrated distinguishable domain structure as on the original English version. Significant associations were found between lower QOL and more severe motor disability. Consistent with the English version, the highest correlation between the primary caregiver and child forms on QOL was in the domain of functioning. Results of this study indicate that the Chinese CP QOL-Child appears to be valid for use in Mandarin-Chinese speaking children with cerebral palsy.

The aim of this study was to determine the percentage of lymphocyte subsets in peripheral blood in patients with active tuberculosis. A total of 21 patients with active tuberculosis and 15 healthy volunteers were included in the study. T-lymphocyte subsets, B-lymphocytes (CD19+ cells), natural killer (NK) cells and cells positive for costimulatory molecules CD28 and CD152 were evaluated using flow cytometry. Patients with tuberculosis had a significantly decreased percentage of CD3+ and CD3+CD4+ cells, and a significantly decreased ratio of CD3+CD4+ to CD3+CD8+ cells compared with healthy controls. In contrast, the percentage of B-cells (CD19+ cells), CD3+CD8+ cells, CD28+ cells, CD152+ cells, and subpopulations of CD4+CD152+, CD8+CD152+ and CD8+CD28+ T-cells were all significantly increased compared with healthy controls. There were no statistically significant differences in the percentages of NK cells or CD4+CD28+ cells between patients and controls. These results indicate that patients with active tuberculosis have altered lymphocyte homeostasis.

Thirty male volunteers participated in a study evaluating the effect of workspace envelope (work height and reach distance) and handle orientation on grip force capacity. Maximum voluntary power grip exertions were recorded using instrumented tool handles under three conditions: a pistol grip tool handle oriented horizontally and vertically and a right angle tool handle oriented horizontally. Significant main effects of handle height and reach location on normalized grip force capacity were observed with the horizontally oriented pistol grip and right angle handles, whereas only an interaction effect was observed with the vertically oriented pistol grip handle. Comparison of results to scores produced with a job assessment tool (RULA) is included as an appendix. The proposed methodology can provide information useful to job, workstation or tool design directed toward best accommodating the physical capacities of workers performing hand tool tasks.

Compound A (3-{2-oxo-3-[3-(5,6,7,8-tetrahydro-[1,8]napthyridin-2-yl)propyl]-imidazolidin-1-yl}-3(S)-(6-methoxy-pyridin-3-yl)propionic acid), a hydrophilic zwitter-ion, is a potent and selective alphavbeta3 integrin antagonist currently under clinical development for the treatment of osteoporosis. The mechanism of renal excretion of compound A was investigated using a combination of in vivo and in vitro approaches. In rats, renal excretion of compound A involved tubular secretion; ratios between renal clearance, corrected for unbound fraction in plasma (CLr,u) and glomerular filtration rate (GFR) were greater than unity (2-5). The tubular secretion of compound A was saturable at high plasma levels (26 microM), and was inhibited significantly, although modestly (about twofold) by relatively high plasma concentrations of the organic anion PAH (160 microM) and the cation cimetidine (about 400 microM), but not by the P-gp inhibitor quinidine (about 50 microM). However, compound A (about 100 microM) had a minimal effect on CLr/GFRs for cimetidine and PAH. In rhesus monkeys, renal elimination of compound A also involved tubular secretion, with a CLr,u/GFR ratio of about 30. The renal secretion of compound A was not affected by either cimetidine (about 120 microM) or PAH (about 80 microM). Similarly, compound A (about 40 microM) had a minimal effect on the renal tubular secretion of both cimetidine and PAH. At the doses studied, neither rat nor monkey plasma protein binding of compound A, cimetidine or PAH was affected in the presence of each other. In vitro transport studies showed that compound A was not a substrate for P-gp in the Caco-2, human MDR1 and mouse mdr1a transfected LLC-PK1 cell lines. In an uptake study using rOAT1 and rOAT3 transfected HEK cell lines, compound A was shown to be a substrate for rat OAT3 (Km= 15 microM), but not rat OAT1. The results suggest that the tubular secretion of compound A is not mediated by P-gp, but rather is mediated, at least in part, via the organic anion transporter OAT3, the renal transporter shown to be capable of transporting both the organic anion PAH and the organic cation cimetidine. Although there is a possibility for pharmacokinetic interactions between compound A and substrates or inhibitors of OAT3, at the renal excretion level, the magnitude of interaction would likely be modest in humans at clinically relevant doses.

1. The disposition and metabolism of ertapenem, a carbapenem antibiotic, was examined in rat, monkey and man. Sprague-Dawley rats and Rhesus monkeys were given, by intravenous administration, radiolabelled doses of ertapenem (60 and 30 mg kg(-1), respectively), and healthy normal volunteers received a single fixed dose of 1000 mg. Urine and faeces were collected for determination of total radioactivity. 2. In healthy volunteers, [14C]ertapenem was eliminated by a combination of hydrolytic metabolism to a beta-lactam ring-opened derivative and renal excretion of unchanged drug. Approximately equal amounts were excreted as a beta-lactam ring-opened metabolite and unchanged drug (36.7 and 37.5% of dose, respectively). A secondary amide hydrolysis product accounted for about 1% of the dose in man. About 10% of the administered radioactivity was recovered in faeces, which suggested that a minor fraction underwent biliary and/or intestinal excretion. 3. In animals, a greater fraction of the dose was eliminated via metabolism; excretion of unchanged drug accounted for 17 and 5% of dose in rats and monkeys, respectively. In monkeys, the beta-lactam ring-opened and amide hydrolysis metabolites accounted for 74.8 and 7.59% of the dose, respectively, whereas in rats, these metabolites accounted for 31.9 and 20% of dose, respectively. 4. In vitro studies with fresh rat tissue homogenates indicated that lung and kidney were the primary organs involved in mediating formation of the beta-lactam ring-opened metabolite. The specific inhibitor of dehydropeptidase-I, cilastatin, inhibited the in vivo and in vitro metabolism of ertapenem in rats, which suggested strongly that the hydrolysis of ertapenem in lung and kidney was mediated by this enzyme.

1. The study investigated mechanisms underlying the pharmacokinetic differences of two zwitterionic diastereomers ((3S)-3-[(3R or 3S)-2-oxo-3-[3-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl)propyl]pyrrolidin-1-yl]-3-quinolin-3-ylpropanoic acid) with different lipophilicities using a combination of in vivo and in vitro approaches. 2. In rat, both isomers possessed comparable plasma clearances (CL). However, the more lipophilic diastereomer I exhibited a higher metabolic clearance (>2-fold higher than II), whereas the hydrophilic zwitterion II exhibited a higher biliary clearance (approximately 5-fold higher than I). Following oral administration, the bioavailability (F) of I (17%) was much higher than that of II (1%). 3. Consistent with these in vivo observations and the expectation based on their lipophilicity differences, the metabolism in rat liver microsomes was faster and the permeability in Caco-2 and LLC-PK1 cells and in situ rat intestinal loop was better for I than for II. 4. Only the absorption of the more lipophilic diastereomer I was subjected to an efflux system in the Caco-2 and in situ rat intestinal loop models. I was a good substrate for P-glycoprotein (P-gp) in both the human MDR1 and mouse mdr1a transfected cell lines, and in the wild-type mdr1a (-/-) mouse when compared with the P-gp-deficient mdr1a (-/-) mouse. Concomitant administration of I with verapamil in rat caused significant increases in oral AUC, F and Cmax of I without affecting its CL, further supporting the effect of P-gp in limiting the intestinal absorption of I in vivo in this animal model. 5. Since the findings that the lipophilic diastereomer I, but not II, was a good P-gp substrate were not in line with the observations that I was excreted to bile much slower than II and that I was absorbed better than II, the results suggested that P-gp played a minor role to the observed differences in the biliary excretion and intestinal absorption of the diastereomers I and II in rat.

Echocardiography played an important role in the screening and diagnosis of hypertrophic cardiomyopathy. In the study reported here, we attempted to evaluate the effects of birth season, breed, sex, and sire family on cardiac morphology determined in pigs by use of echocardiography.A total of 411 pigs (mean body weight and age of 105.7 +/- 10.6 kg and 214.4 +/- 25.5 days, respectively) with different genetic backgrounds (Landrace, Yorkshire, and their two-way crossbred) were studied. Cardiac morphologic measurements included thickness of left ventricle and interventricular septum at end-systolic and end-diastolic phases. Meanwhile, the statistical model included the following effects: birth season, breed, sex, interaction between breed and sex, sire family, body weight, and age.Mean cardiac morphologic measurements were as follows: thickness of the interventricular septum at end-systolic and end-diastolic phases was 1.74 and 1.14 cm, respectively; and thickness of the left ventricular free wall at end-systolic and end-diastolic phases was 1.81 and 0.98 cm, respectively. Medium positive correlations existed among the cardiac morphologic measurements r = 0.31 to 0.53; P0.001). Pigs born in spring had significantly (P0.05) lower cardiac thickness at the end systolic phase than did pigs born in other seasons, and Landrace pigs had higher cardiac morphologic measurements than did Yorkshire and two-way crossbred pigs. Additionally, thickness of interventricular septum at the end-diastolic phase in male pigs was significantly higher than that in female pigs (P0.05). Cardiac morphologic measurements for the sire family were significantly (P0.05) different, and contributed 77.2 to 87.9% of the total variation, suggesting that genetic variation in cardiac morphology might exist in pigs.Cardiac morphology of pigs might be influenced by genetic background. The effects of birth season, breed, sire family, and sex should be adjusted when using pigs as an animal model for comparative cardiovascular studies.

The purpose of this study was to examine the relationships between severity of disability and factors such as rehabilitation fees, length of stay and efficiency for hospitalized stroke patients. One hundred and seven first-time stroke patients were studied consecutively for this study. They were recruited from a rehabilitation ward in a university medical center during 1997. Functional ability was evaluated using the Functional Independence Measure (FIM) instrument on admission and discharge. Stroke patients who presented with similar degrees of disability were put together using the admission FIM score (FIM Function-Related Groups, FIM-FRGs) for further analysis. Twenty-eight (26.2%) patients examined were categorized as severely disabled (scored 18-36), 48 (44.8%) moderately disabled (scored 37-72) and 31 (29.0%) mildly disabled (scored 73-126). The average expense on rehabilitation fees, for the average rehabilitation length of stay (LOSR) of 34.7 +/- 16.7 days, was NT$ 27,645 +/- 13,812. The FIM score improved from 56.8 +/- 24.2 on admission to 76.6 +/- 26.2 at discharge, with a rehabilitation efficiency index (EIR) of 0.7 +/- 0.7. Further analysis indicated that there were significant differences among the three disability groups on rehabilitation fees and LOSR while EIR was unaffected. The findings of this study suggest that FIM-FRGs can differentiate different rehabilitation needs in terms of rehabilitation fees and LOSR; therefore, a prospective case payment system based on FIM-FRGs is suggested for stroke rehabilitation reimbursement scheme in the future.

Compound I (1-(3-chlorophenyl)-4-[(1-(4-cyanobenzyl)-1H-imidazol-5-yl)methyl]piperazin-2-one) is a potent and selective inhibitor of farnesyl-protein transferase (FPTase). The pharmacokinetics and metabolism of compound I displayed species differences in rats and dogs. After oral administration, the drug was well absorbed in dogs but less so in rats. Following i.v. administration, compound I was cleared rapidly in rats in a polyphasic manner with a terminal t(1/2) of 41 min. The plasma clearance (CL(p)) and volume of distribution (V(dss)) were 41.2 ml/min/kg and 1.2 l/kg, respectively. About 1% of the dose was excreted in rat bile and urine as unchanged drug over a period of 24 h, suggesting that biotransformation is the major route of elimination of compound I. Using liquid chromatography (LC)-tandem mass spectometry, nineteen metabolites of compound I were identified in urine and bile from dogs and rats. Structures of two major metabolites were confirmed by LC-NMR. N-Dealkylation and phase II metabolism were the major metabolic pathways. Animal and human liver microsomal intrinsic clearance values were scaled to predict hepatic clearance and half-life in humans, and the predicted values were in good agreement to the in vivo data.

All current 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors [simvastatin (SV), lovastatin (LV), atorvastatin, pravastatin, fluvastatin, and cerivastatin] are believed to undergo an atypical beta-oxidation of the dihydroxy heptanoic or heptanoic acid side chain. Metabolites, which are shortened by two- and/or four-carbon units consistent with beta-oxidation products, have been reported exclusively in rodents following LV and SV administration and across species (rodents, dogs, and humans) following the other statins. In this study, in vitro formation of a beta-oxidation product of simvastatin hydroxy acid (SVA) and its intermediates in mouse livers is described. Incubation of SVA with mouse liver preparations fortified with CoASH and ATP led to formation of SV and two major products (P1 and P2). Based on mass spectrometry (MS), tandem mass spectrometry, and/or NMR spectral characteristics, P1 was an alpha,beta-unsaturated metabolite, formed by dehydration of the D,D-dihydroxy heptanoic acid side chain, whereas P2 was probably the L,D-dihydroxy acid isomer of SVA, formed by stereospecific hydration of P1. When NAD(+) was also included in the incubation mixture, there were two additional metabolites with the MS and/or NMR characteristics consistent with a two-carbon shortened product (P3) and its dehydrated derivative (P4). In a complete incubation system with all cofactors (ATP, CoASH, NAD(+), and NADPH) present, there was an additional product with MS spectra and liquid chromatography retention time identical to the beta-oxidized, unsubstituted pentanoic acid metabolite (P5) detected in rats and mice following simvastatin administration. The involvement of CoASH and NAD(+) and the presence of the four metabolic intermediates suggest that SVA (and presumably the other statins) is a substrate for the beta-oxidation enzyme complex in mice. Additionally, the present finding of CoASH-dependent formation of SV substantiates a mechanism proposed previously for the in vivo lactonization of statin hydroxy acids.

The purpose of this study was to determine whether the admission functional status influences the functional gain and efficiency of stroke rehabilitation. We prospectively studied 105 first time stroke patients consecutively admitted to the inpatient rehabilitation department of a university hospital during 1997. Functional status was assessed with the Functional Independence Measure (FIM) instrument on admission and discharge of inpatient rehabilitation program. The patients were stratified into three groups according to their FIM total scores on admission, i.e., 18 to 36, 37 to 72, and 73 to 126. One-way ANOVA with Tukey's studentized range tests indicated that patients with FIM total scores ofor = 73 at admission were significantly younger (58.2 +/- 12.3 yr) and scored lower functional gain (16.6 +/- 11.7) than those who scored ofor = 36 (66.3 +/- 9.4 yr) of age and functional gain of (27.6 +/- 23.3). However, there were no significant differences on rehabilitation efficiency among the three groups. The findings of this study suggest that the functional groups stratified by admission FIM score seem to predict the degree of functional gain for first time stroke patients after inpatient rehabilitation.

One of the problems in nursing home care in Taiwan is resident restraint, including physical and chemical restraints. This pre-experimental study was conducted to investigate whether a restraint reduction program could reduce the prevalence of restraint in nursing homes. Three registered nursing homes were randomly selected from nursing homes in the Kaohsiung area. Staff and residents of these nursing homes were educated in restraint alternatives, balance training and managing behavior problems in one month of interventions. Three days before and after interventions, prevalence of restraints, falls, and of pressure sores, balance reaction, frequency of agitation, use of psychotic drugs, as well as the restraint knowledge of the nursing staff, was measured. After the restraint reduction program, the prevalence of restraint and frequency of resident agitation decreased significantly. The prevalence of falls and pressure sores of residents was not changed significantly. The restraint knowledge of the nursing staff significantly increased after the restraint reduction program. The information from this study led to a better strategy to reduce restraint for the elderly in nursing homes. The results could also provide a model to improve the quality of care in nursing homes in Taiwan.

Tumor-selective delivery of doxorubicin by a prostate-specific antigen (PSA)-targeted peptide conjugate prodrug of doxorubicin was demonstrated in a nude mouse xenograft model of human prostate cancer. The prodrug (referred to as doxorubicin conjugate) contains doxorubicin linked to a seven-amino acid peptide conjugate that was designed to increase delivery of doxorubicin to tumor sites through the hydrolytic properties of PSA, which prostate tumors express in high amounts. Following i.p. administration of the doxorubicin conjugate to mice, tumor exposure to doxorubicin was increased 2.5-fold as compared with that achieved after an equimolar dose of doxorubicin itself. However, in heart tissue, the site of clinical dose-limiting toxicity, doxorubicin concentrations observed after administration of doxorubicin conjugate were substantially lower than those in mice that received doxorubicin itself. While the prodrug provided selective delivery of doxorubicin to tumor tissue, there was substantial non-PSA-specific formation of doxorubicin in laboratory animals, a factor that would limit the extent of therapeutic gain of the prodrug. Following i.v. administration to mice, rats, dogs, and monkeys, about one-third of the dose was metabolized to doxorubicin. In tumor-bearing mice, the fraction of the dose metabolized to doxorubicin appeared even higher. This is likely the result of conjugate conversion to doxorubicin by both PSA-specific (in tumor) and non-PSA-specific proteolytic activities. In vitro studies provided further support for the PSA specificity of metabolism; LNCaP cells mediated rapid metabolism of the conjugate, while DuPRO-1 cells, which are deficient in PSA, were incapable of metabolism.

Secondary hypertension is a potentially curable disease. One-hundred-and thirty six children was diagnosed as hypertension in the National Taiwan University Hospital from January 1992 to June 1998 and they were retrospectively reviewed and analysed for the etiological factors, presentation, and clinical outcome. The most common cause of hypertension was coarctation of aorta in infants and systemic lupus nephritis in adolescents. These children often presented symptoms and signs not directly related hypertension (37.5%). Twenty eight children (20.6%) died. The hypertension of the survival had been controlled by surgery, chronic hemodialysis, or medication.

Methylation at the 2-position of the imidazole ring of IBN (I), a 1, 5-substituted imidazole-containing compound, was carried out to minimize its inhibition of rat cytochrome P450 (CYP)3A activity. The resulting analog 2-MIBN (II) exhibited an inhibitory potency 70-fold weaker (K(i) = 25 microM) than that of I (K(i) = 0.3 microM) toward CYP3A, the major rat liver microsomal P450 isoform(s) for the metabolism of I and II by rat liver microsomes in the presence of NADPH. The structural modification did not switch the major metabolic pathways for I and II, but significantly decreased the affinity of II to the metabolizing enzyme(s) as reflected by the difference in their K(i) values for CYP3A. Enzyme kinetic studies also demonstrated that I had a lower apparent K(m) (0.3 microM) than than II (18 microM), but an apparent V(max) 14 times lower than II. This finding indicates that methylation at the imidazole ring reduced the affinity of the compound to CYP3A, but increased the catalytic capacity, turning I as a substrate of low K(m) value but low capacity into a compound of high K(m) but high capacity for the metabolism. Our results suggest the significance of substrate concentration in comparing the metabolic stability of compounds with different kinetic parameters. Although higher intrinsic clearance is implied for I when the substrate concentration is below or close to its K(m) value, higher metabolic rate was constantly seen with II over micromolar range. The different kinetic parameters of I and II may also explain the observation that no significant difference in pharmacokinetic behavior was seen after an i.v. administration of I and II to the rat.

L-754,394, a furanopyridine derivative, is an experimental HIV protease inhibitor. Previous studies from this laboratory have demonstrated that L-754,394 is cleared very rapidly in animals, and that this drug is a potent mechanism-based inactivator (suicide inhibitor) for CYP3A4 in human liver microsomes. Because L-754,394 is a high-clearance drug and an enzyme inactivator, it is expected that this drug will be subject to significant first-pass metabolism, and that the degree of enzyme inactivation will be dependent not only on the dose, but also on the route of administration. The purpose of this study is to examine the effects of dose and route of administration on the kinetics of L-754,394 using rats and dogs as animal models. In both rats and dogs, L-754,394 exhibited marked dose-dependent pharmacokinetics after i.v. and oral administration. Irrespective of i.v. or oral administration, the area under the plasma concentration-time curve from zero to infinity increased with dose in a greater than proportional manner. However, the magnitude of area under the plasma concentration-time curve from zero to infinity increase was much greater after oral dosing than after i.v. administration, indicating route-dependent pharmacokinetics. Data from in vitro and in vivo studies suggested that the dose- and route-dependent pharmacokinetics were due mainly to the inactivation (destruction) of the enzymes responsible for its own metabolism.

We report the case of a 36-year-old Chinese man with a history of complex partial seizure of temporal lobe origin since the age of 12 years, superimposed by myasthenia gravis since the age of 27 years and psoriasis vulgaris since the age of 29 years. With an eight-year follow-up, the above three diseases remained without complete remission. Anticonvulsant therapy (phenytoin and trimethadione) caused drug-induced myasthenia gravis, which should gradually disappear after discontinuing the drugs. However, the myasthenic symptoms and serum acetylcholine receptor antibody persisted following the discontinuation of phenytoin in our patient. Myasthenia gravis and psoriasis are both autoimmune diseases and correlate with specific human histocompatibility antigens. This suggests a close connection between these two diseases. The coexistence of epilepsy, myasthenia gravis and psoriasis vulgaris has not been previously reported, and to the best of our knowledge, our patient is the first reported case. The relationship among these three diseases requires further investigation.

The cytochrome P-450 (CYP)3A4-mediated metabolism of diclofenac is stimulated in vitro by quinidine. A similar effect is observed in incubations with monkey liver microsomes. We describe an in vivo interaction of diclofenac and quinidine that leads to enhanced clearance of diclofenac in monkeys. After a dose of diclofenac via portal vein infusion at 0.055 mg/kg/h, steady-state systemic plasma drug concentrations in three male rhesus monkeys were 87, 104, and 32 ng/ml, respectively (control). When diclofenac was coadministered with quinidine (0.25 mg/kg/h) via the same route, the corresponding plasma diclofenac concentrations were 50, 59, and 18 ng/ml, representing 57, 56, and 56% of control values, respectively. In contrast, steady-state systemic diclofenac concentrations in the same three monkeys were elevated 1.4 to 2.5 times when the monkeys were pretreated with L-754,394 (10 mg/kg i.v.), an inhibitor of CYP3A. Further investigation indicated that the plasma protein binding (99%) and blood/plasma ratio (0.7) of diclofenac remained unchanged in the presence of quinidine. Therefore, the decreases in plasma concentrations of diclofenac after a combined dose of diclofenac and quinidine are taken to reflect increased hepatic clearance of the drug, presumably resulting from the stimulation of CYP3A-catalyzed oxidative metabolism. Consistent with this proposed mechanism, a 2-fold increase in the formation of 5-hydroxydiclofenac derivatives was observed in monkey hepatocyte suspensions containing diclofenac and quinidine. Stimulation of diclofenac metabolism by quinidine was diminished when monkey liver microsomes were pretreated with antibodies against CYP3A. Subsequent kinetic studies indicated that the K(m) value for the CYP-mediated conversion of diclofenac to its 5-hydroxy derivatives was little changed (75 versus 59 microM), whereas V(max) increased 2.5-fold in the presence of quinidine. These data suggest that the catalytic capacity of monkey hepatic CYP3A toward diclofenac metabolism is enhanced by quinidine.

A 41-year-old man was admitted for symptoms of progressive congestive heart failure. His family history and the results of a physical examination were highly suggestive of Osler-Weber-Rendu disease (hereditary hemorrhagic telangiectasia, HHT). Cardiac catheterization and hepatic angiography demonstrated HHT with left-to-right shunting from the liver. The patient underwent transcatheter arterial embolization (TAE) of the right hepatic artery. We performed both Doppler sonography and angiography before and after TAE. The treatment improved the clinical manifestations of congestive heart failure, including the edema of the leg and dyspnea. Doppler sonographic studies also showed an increased resistive index in the right hepatic artery and decreased flow volumes and velocities in the right and middle hepatic veins, respectively, after treatment. Corresponding changes on angiography after TAE showed decreased right hepatic arterial flow and nonopacified branches distal to the coils, disappearance of the mottled hepatogram in the right lobe, reduction of contrast agent staining, and enhanced calibers in the right and middle hepatic veins. This case illustrates that qualitative and quantitative studies with duplex and color Doppler ultrasound can be used to detect or define the extent of hepatic involvement in HHT patients before TAE, monitor hemodynamic changes of the intrahepatic vasculature after TAE, evaluate the efficacy of treatment, and possibly obviate the need for repeated angiography for diagnosis only.

This prospective study evaluated the clinical use of the Fugl-Meyer Balance Scale (FMBS) on stroke patients during hospitalization and assessed the relationship between balance score at admission to the rehabilitation program and functional outcome at discharge. One hundred and sixty-three stroke patients admitted to the in-patient rehabilitation department of a university-based medical center between January 1 and December 31, 1997 were recruited for this investigation. Functional ability was evaluated with the Functional Independence Measure (FIM) instrument, and balance was measured using the 7-item Fugl-Meyer Balance Scale. These measures were assessed both at admission to and discharge from the inpatient rehabilitation program. Pearson correlation and multiple regression analyses were used to determine the relationship between balance and functional ability scores at admission and rehabilitation outcomes at discharge, including length of stay, functional gain, and efficiency. The results demonstrated that the balance score at admission accounted for 6% of the variation in length of stay, once demographic influences were controlled. The FIM efficiency score could possibly be predicted by the balance ability at admission, which accounted for 3% of the variance. However, the balance score could not provide predictive information about the FIM gain beyond that already provided by the FIM score at admission, which accounted for 4% of the variance with demographic factors controlled. Overall, balance ability at admission, assessed by the Fugl-Meyer Balance Scale, had no or at least only little, contribution to account for the variance in rehabilitation outcomes. These findings suggest that the use of Fugl-Meyer Balance Scale at admission to stroke inpatient rehabilitation seemed not to enhance the ability to predict rehabilitation outcomes.

Indinavir, a potent and specific inhibitor of HIV protease, is a known substrate of cytochrome P-450 (CYP) 3A and p-glycoprotein. The purpose of this study is to investigate and compare the inducing effect of dexamethasone (DEX) on CYP3A and p-glycoprotein in the hepatic and intestinal first-pass metabolism of indinavir in rats. Pretreatment of rats with DEX had little effect on the pharmacokinetics (Cl and T(1/2)) after i.v. administration of indinavir, whereas DEX markedly altered the peak concentration (C(max)) and bioavailability of indinavir after oral dosing. The C(max) decreased from 2.8 microM in control rats to 0.28 microM in DEX-treated rats, and bioavailability decreased from 28 to 12.4%. The decreased bioavailability after DEX pretreatment was due mainly to an increase in first-pass metabolism. Intestinal first-pass metabolism (E(G)) increased from 6% in control rats to 34% in DEX-treated rats, and hepatic first-pass metabolism (E(H)) increased from 65 to 82%. Analysis of in vitro kinetic data revealed that the increased intestinal and hepatic metabolism by DEX was attributed to an increase in the V(max), as a result of CYP3A induction, without a significant change in the K(m) values. DEX pretreatment also induced p-glycoprotein in the intestine and liver of rats. p-Glycoprotein appeared to increase the intestinal metabolism of indinavir whereas it had little effect on the hepatic metabolism of indinavir. Although it has been suggested that the role of intestinal metabolism for some drugs is quantitatively greater than that of hepatic metabolism in the overall first-pass metabolism, the contribution of intestinal metabolism to the overall first-pass metabolism of indinavir in rats is not quantitatively as important as the hepatic metabolism, regardless of DEX induction.

Previous studies in vitro have revealed that L-754,394, an HIV protease inhibitor, is a potent suicide inhibitor of cytochrome P-450 enzymes. The present report examines the effect of chronic treatment of L-754,394 on hepatic cytochrome P-450s in adult male rats. L-754,394 was administered orally once a day for 7 days and resulted in significant changes in marker activities. An unusual parabolic (ascending, then descending) profile was observed for testosterone 2beta-/6beta-(CYP 3A1/2-catalyzed) hydroxylase activities during the 7-day treatment with 20 mg/kg L-754,394. These activities, which were elevated 2-fold on day 2, returned to basal levels by day 8. In contrast, testosterone 2alpha-/16alpha-(CYP2C11-catalyzed) hydroxylase activities showed an opposite parabolic (descending, then ascending) profile during the same period, reducing to 40% of control activities on day 4, followed by a rebounding trend. Immunoquantitation of CYP 3A1/2 and 2C11 showed that the expressed protein levels were in parallel with the associated activities. Furthermore, mRNA levels of CYP 3A2 and CYP2C11 showed the same trends as the protein expression of the respective isoforms. These observations show that L-754,394 perturbs the relative abundance of P-450 isoforms in rat liver by affecting the regulation at a pretranslational step. This may further involve a disturbance of hormonal homeostasis. Although serum levels of testosterone did not show a marked change during treatment, thyroxine and triiodothyronine markedly decreased on days 2 and 4, and subsequently increased to basal levels.

Experiments were carried out to explore the possible role played by the nitric oxide (NO) system in the organum vasculosum laminae terminalis (OVLT) of rat brain in arterial pressure regulation. Intracerebroventricular (ICV) or intra-OVLT administration of NO donors such as hydroxylamine, sodium nitro-prusside or s-nitro-acetylpenicillamine caused an up to 55 mmHg decrease in blood pressure (BP) but an increase in NO release (measured by porphyrin/nafion coated carbon fibre electrodes in combination with voltammetry) in the OVLT. In contrast, ICV or intra-OVLT administration of N(G)-nitro-L-arginine methyl ester (L-NAME; a constitutive NO synthase inhibitor) caused an up to 45 mmHg increase in BP but a fall in NO release in the OVLT. Compared with the BP responses induced by ICV injection of NO donors or NO synthase inhibitors, the OVLT route of injection required a much lower dose of NO donors or NO synthase inhibitors to produce a similar BP effect. The depressor effects induced by ICV or intra-OVLT administration of NO donors were attenuated by pretreatment with intra-OVLT injection of methylene blue (an inhibitor of guanylate cyclase), haemoglobin (a NO scavenger), L-NAME or spinal transection. On the other hand, the L-NAME-induced pressor effects were attenuated by pretreatment with intra-OVLT injection of L-arginine or spinal transection. The data suggest that activation of cyclic GMP-dependent NO synthase in the OVLT of rat brain causes cyclic GMP-dependent decreases in arterial pressure via inhibiting the sympathetic efferent activity.

The purpose of this prospective study was to investigate the influence of rehabilitation therapy on the prognosis for stroke patients. Sociodemographic and clinical factors were collected in a sample of 147 stroke patients (81 men and 66 women) admitted to the inpatient rehabilitation department at our university hospital over 10 days between January 1, 1997 and December 31, 1997. Functional Independence Measure (FIM) scores at discharge and gains during rehabilitation period were used as the prognosis index. Statistical techniques with univariate and multiple regression analyses indicated that significant predictors of discharge FIM scores include age, previous attacks twice or over, medical comorbidities, sensory and orientation impairments, and dementia. In addition, previous stroke attacks twice or over and sensory impairment were significant predictors of FIM gains during rehabilitation period. We concluded that: 1) age is a critical factor to determine the rehabilitation outcome, but may not be an important factor to predict the ability for the improvement through rehabilitation therapy; 2) the delay of rehabilitation therapy may not affect the potential for further improvement; 3) patients with low initial functional level may have poor final outcome, they may still have good rehabilitation potential to improve the functional level; 4) complications of stroke may affect the rehabilitation outcome and should be prevented; and 5) patients with impaired mental status should not routinely be excluded from rehabilitation programs.

To study the influences of procainamide (PA) on thrombin-induced rabbit platelet aggregation and thromboxane B2 (TXB2) production in vitro.Turbidimetry and radioimmunoassay were used.PA 8.5, 34, 136, and 544 mumol.L-1 inhibited thrombin-induced platelet aggregation and TXB2 production, and the inhibitory rates were 45% +/- 37%, 48% +/- 32%, 88% +/- 23%, 92% +/- 15% and 53% +/- 24%, 65% +/- 26%, 90% +/- 6%, 95% +/- 6%, respectively. There was positive correlation between PA concentration and efficiency of inhibition of platelet aggregation and TXB2 production, and also between the inhibition % of platelet aggregation and that of production of TXB2. The three linear equations and main parameters were Y = 0.2075X-4.9157, r = 0.9985; Y = 0.9546X-34.6724, r = 0.9921; Y = 0.8202X + 19.7062, r = 0.9921.PA inhibited thrombin-induced platelet aggregation and TXB2 production in rabbits.

Efavirenz (EFV, Sustiva, Stocrin, DMP-266, L-743,726) is a potent and selective non-nucleoside inhibitor of HIV-1 reverse transcriptase. Pharmacokinetics of EFV was studied in rats and monkeys, the safety assessment species. In rats, after 2 and 5 mg/kg i.v. administrations, the mean CLp, Vdss, and T1/2 were 67 ml/min/kg, 5.0 liters/kg, and 1 h, respectively. EFV was metabolized completely, and the products were excreted almost exclusively via bile. At the higher dose of 15 mg/kg, the CLp was reduced by 36%, implying saturation of metabolism processes. A similar phenomenon occurred in monkeys, where the CLp declined by 60% as the i.v. dose was increased from 5 to 15 mg/kg. After oral dosing, the bioavailability of EFV in rats (10 mg/kg) and monkeys (2 mg/kg) was 16% and 42%, respectively. Higher doses in both species led to disproportionate increases in the AUC and higher Tmax values, suggesting saturation of metabolism and/or prolongation of absorption. The delay in Tmax was more pronounced in monkeys where the plasma concentrations reached plateaus and were sustained for 4 to 20 h. In rats, the prolongation of absorption was due to delayed gastric emptying as demonstrated by10-fold slower transit of [14C]polyethylene glycol through the stomach of EFV-pretreated animals. The delayed gastric emptying in monkeys also was observed when the animals dosed at 160 mg/kg exhibited emesis, 8 h postdose, which was found to contain a substantial portion of the dose. These results demonstrated that in rats and monkeys, both delayed gastric emptying and saturation of metabolic processes played significant roles in the nonlinear pharmacokinetics of EFV.

The barriers to oral delivery of the hydrophilic zwitterion L-767, 679 (I) and its carboxyl ester prodrug L-775,318 (II) were examined. In the Caco-2 cell model, transport of II, but not I, was strongly oriented in the secretory direction. The basal-to-apical transport of II displayed saturable kinetics and was markedly inhibited by verapamil and quinidine, known P-glycoprotein inhibitors. In Caco-2 cells, metabolism of I was not observed, whereas hydrolysis of II was modest (/=20%). In the in situ rat intestinal loop model, verapamil did not affect the absorption of I but significantly increased the absorption of II. I was resistant to intestinal metabolism, whereas II underwent hydrolysis partially in rat lumen but more extensively in rat intestinal tissue and blood. In vitro metabolism studies indicated that verapamil also inhibited the hydrolysis of II in rats. The inhibition was relatively specific for the intestinal and not the luminal esterases. These results suggested that the intestinal absorption of I was limited not by intestinal efflux or metabolism but more likely by the low lipophilicity of I. However, an efflux system, likely mediated by P-glycoprotein, played an important role in limiting the absorption of II. In rats, metabolism served as an additional barrier to the absorption of II. Verapamil increased the intestinal absorption of the prodrug by inhibiting the efflux system in the two models studied, as well as possibly inhibiting metabolism in rats. For the first time, secretory transport was identified as a cause of the failure to increase the absorption of a lipophilic and cationic prodrug developed to overcome the absorption problem.

We describe a male infant with unusual facial appearance, relative pancytopenia, bilateral simian creases, and an accessory nipple. Cytogenetic analysis showed deletion of the long arm of chromosome 11 [46,XY,del(11)(pter--q23.2:)]. Bone-marrow study showed a myelodysplastic change of hemopoietic cells compatible with peripheral blood findings. Pachygyria of the temporal and frontal lobes was demonstrated by magnetic resonance image (MRI) of the brain. We present our findings in order to contribute to the information on 11q23 deletion.

Congenital nephrotic syndrome of Finnish type is a rare disease in Taiwan characterized by intrauterine onset of massive urinary loss of protein. We describe a typical baby of congenital nephrotic syndrome with generalized edema occurring at 3 months of age. Renal biopsy at 4 months of age showed a tubular microcystic change in histology. He had a partial response to corticosteroid. We tried persantin, indomethacin, and captopril since 10 months of age without significant improvement. The baby suffered from recurrent infections and respiratory difficulties due to having upper airway edema since 3 months of age. The baby passed away at 1 year and 2 months of age with severe psychomotor retardation. The first try of the combination of persantin, indomethacin, and captopril for congenital nephrotic syndrome is described.

Montelukast sodium [1-([(1(R)-(3-(2-(7-chloro-2-quinolinyl)-(E)- ethenyl)phenyl)-3-(2-(1-hydroxy-1-methylethyl)phenyl)propyl)thio]methyl)cyclopropylacetic acid sodium salt] (MK-476, Singulair) is a potent and selective antagonist of the cysteinyl leukotriene (Cys-LT1) receptor and is under investigation for the treatment of bronchial asthma. To assess the metabolism and excretion of montelukast, six healthy subjects received single oral doses of 102 mg of [14C]montelukast, and the urine and feces were collected. Most of the radioactivity was recovered in feces, with/=0.2% appearing in urine. Based on these results and the reported modestly high oral bioavailability of montelukast, it could be concluded that a major part of the radioactivity was excreted via bile. A second clinical study was conducted to identify biliary metabolites of montelukast. The bile was aspirated using a modified procedure involving a nasogastric tube placed fluoroscopically near the ampulla of Vater, after an oral dose of 54.8 mg of [14C]montelukast. This technique appears to be a new application for drug metabolism studies. The study was conducted with fasted and nonfasted subjects, with the bile being aspirated continuously under suction over periods of 2-8 hr and 8-12 hr after the dose, respectively. Two hours before the end of the collection procedure, cholecystokinin carboxyl-terminal octapeptide was administered iv to stimulate gallbladder contraction. Plasma samples also were collected periodically over 10 hr. Due to the nature of the collection procedure and the limited sampling time, recovery of radioactivity in bile was incomplete and varied from 3 to 20% of the dose. Radiochromatographic and LC-MS/MS analyses of bile showed the presence of one major and several minor metabolites, along with small amounts of unchanged parent drug. The minor metabolites were identified, by LC-MS/MS comparison with synthetic standards or by NMR, as acyl glucuronide (M1), sulfoxide (M2), 25-hydroxy (a phenol, M3), 21-hydroxy (diastereomers of a benzylic alcohol, M5a and M5b), and 36-hydroxy (diastereomers of a methyl alcohol, M6a and M6b) analogs of montelukast. The major metabolite was characterized as a dicarboxylic acid (M4), a product of further oxidation of the hydroxymethyl metabolite M6. Chiral LC-MS/MS analyses of M4 revealed that this diacid, like M5 and M6, was formed in both diastereomeric forms. The levels of metabolites in the systemic circulation were low in the fed as well as fasted subjects, with2% of the circulating radioactivity being due to metabolites M5a, M5b, M6a, and M6b. Overall, this bile aspiration technique, which is less invasive than either T-tube drainage or fine-needle percutaneous puncture, provided a convenient and expedient means of identifying the biliary metabolites of montelukast, relatively free of contributions from colonic microflora.

In vitro microsomal formation of primary metabolites of indinavir (CRIXIVAN, MK-0639, L-735,524), an HIV protease inhibitor, were qualitatively similar among the different developmental stages in humans, although the fetal liver had a lower capability to form the metabolites than the pediatric and adult liver. The lower activity of fetal liver was mainly owing to a decrease in the Vmax values. The Vmax value in the fetus was about one-third of that in the adult human, while no significant difference was found in Km values between groups. The liver microsomes were also characterized using P450 markers to examine the development-associated alteration in P450 functional activities. Debrisoquine 4-hydroxylase activity was comparable among the three age groups. In contrast, tolbutamide methyl hydroxylase activity, as well as the CYP3A marker, testosterone 6beta-hydroxylase activity, in the fetal liver microsomes was much lower than in the pediatric and adult by more than 40-fold. However, the difference in testosterone 2beta-hydroxylase and nifedipine N-oxidase activities between fetus and adult was markedly smaller. The ratio of indinavir metabolism in pediatric or adult liver to fetus was 1.7 for pediatric and 3.6 for adult liver microsomes. Similarly, testosterone 2beta-hydroxylase and nifedipine N-oxidase activities showed smaller differences between adult (or pediatric) and fetal liver microsomes than testosterone 6beta-hydroxylase activity. The reason for the observed marked differences in the development-associated alteration may lie in the differences of substrate specificities between CYP3A isoforms.

Montelukast (L-706,631, MK-0476, SINGULAIR), a potent and selective leukotriene D4 (CysLT1) receptor antagonist, is currently under development for the treatment of asthma. In vitro studies were conducted using human liver microsomes to evaluate: 1) the difference in the metabolic kinetics of montelukast between adult and pediatric subjects; 2) the relative contribution of flavin-containing monooxygenase and cytochrome P450 (P450) to the sulfoxidation; and 3) the P450 isoforms responsible for montelukast oxidation. No statistically significant difference was observed in the in vitro kinetics for acyl glucuronidation and oxidative metabolism between the two age groups. Results from studies on heat inactivation of flavin-containing monooxygenase and immunochemical inhibition by an anti-rat NADPH P450 reductase antibody on montelukast oxidation indicated that all oxidative metabolism of montelukast-including diastereomeric sulfoxidations, as well as 21- and methyl-hydroxylations-are catalyzed exclusively by P450. Five in vitro approaches have been used to identify the P450 isoforms responsible for the human liver microsomal oxidation of montelukast. The experimental results consistently indicated that CYP3A4 catalyzes sulfoxidation and 21-hydroxylation, whereas CYP2C9 selectively mediates methyl-hydroxylation.

The metabolism of indinavir, a human immune deficiency virus (HIV) protease inhibitor, has been characterized extensively in rats and humans. All oxidative metabolites found in vivo were formed when indinavir was incubated with NADPH-fortified hepatic and intestinal microsomes obtained from rats and humans. In vitro kinetic studies revealed that Vmax/Km values (microL/min/mg protein) in rat and human liver microsomes were approximately 8- and 2-fold greater than those in the intestinal microsomes of the corresponding species (55.8 and 6.7 for the liver and intestine, respectively, in rats; 16.5 and 7.7 for the liver and intestine, respectively, in humans). However, when Vmax/Km was scaled up to intrinsic clearance (mL/min/kg body weight), hepatic intrinsic clearance was much greater than the intestinal clearance by 50- to 200-fold. These results suggest that the liver plays a much greater role in first-pass metabolism of indinavir than the intestine in both species. Consistently, ketoconazole, a selective inhibitor for CYP3A, and an anti-rat CYP3A1 antibody strongly inhibited hepatic and intestinal metabolism of indinavir in both rats and humans, suggesting the involvement of CYP3A isoforms in both organs. Oral treatment of rats with dexamethasone (50 mg/kg/day for 4 days), a potent CYP3A inducer, increased both hepatic and intestinal metabolism of indinavir by a factor of 7 and 3, respectively. Furthermore, indinavir selectively inhibited 6beta-hydroxylase activity of testosterone, a CYP3A marker activity, in rat and human liver microsomes; the interactions between testosterone and indinavir were competitive with Ki values of1.0 microM.

Acute promyelocytic leukemia (APL;M3) is specifically characterized by a predominance of malignant promyelocytes having atypical reciprocal translocation involving chromosome 15 and 17 [t(15;17)(q22;q11)] resulting in the fusion of retinoic acid receptor alpha (RAR alpha) on chromosome 17 and the putative transcription factor gene PML, ie the translocation generates two fusion transcripts, PML/RAR alpha and RAR alpha/PML. We describe a patient with clinical and morphologic characteristics of atypical APL but with a previously undescribed variant translocation. A 35-year-old Hispanic having atypical APL was referred for cytogenetic evaluation. The cytogenetic findings with GTG-banding coupled with FISH analysis revealed the following karyotype: 46,XX,der(9)t(1;9)(q25;q34)der(9)t(9;?)(q34;?), t(15;17)(q22;q11)ish. der(9)t(1;9)(q25;q34)(WCP1+,WCP9+),t(9;17;15)(q34;q11;q22) (WCP9+,WCP15+,PML+;WCP17+,RAR alpha +;WCP15+,WCP17+,PML-)[20]/46,XX[5]. The chromosome 17q was translocated to the chromosome 15q. However, chromosome 15q including the PML gene normally translocating to 17q and creating the RAR alpha/PML fusion gene, translocated to chromosome 9q. Does this patient have another subset of APL? Or is the genetics of APL different in cases with variant translocations as opposed to those with atypical t(15;17) translocation, though in the majority of the cases their clinical presentation remains the same.