Biomedical subjects

Y Yamazaki

Publications and source records attributed to Y Yamazaki.

At least 325 records · Page 18Linked to original sources

PubMed1996

Effects of KSG-504, a new cholecystokinin-A-receptor antagonist, on pancreatic exocrine and endocrine secretions in rats.

The effects of KSG-504 ((S)-arginium (R)-4-[N-(3-methoxypropyl)-N-pentylcarbamoyl]-5-(2-naphthylsulf onyl) pentanoate monohydrate), a new cholecystokinin (CCK)-A-receptor antagonist, on pancreatic exocrine secretion in anesthetized rats and endocrine secretion in conscious rats were studied. Intravenous injection of KSG-504 inhibited the pancreatic amylase output stimulated by intravenous infusion of CCK-8 in a dose-dependent manner (ED50: 18 micrograms/kg/min). Moreover, KSG-504 significantly reduced the CCK-8-stimulated increases in pancreatic juice volume and outputs of protein, trypsin and lipase. Intraduodenal infusion of casein increased the plasma CCK concentration and the pancreatic amylase output. KSG-504 significantly inhibited the pancreatic amylase output stimulated by casein. Pancreatic juice volume and bicarbonate output were significantly stimulated by intravenous infusion of secretin, but were not changed by KSG-504. When pancreatic exocrine secretion was stimulated by secretin plus CCK-8, KSG-504 suppressed the increases in juice volume and bicarbonate output to the level stimulated by secretin alone. Basal pancreatic amylase output was decreased by KSG-504. KSG-504 decreased the level of plasma immunoreactive insulin (IRI) stimulated by glucose plus CCK-8, but had no effect on IRI stimulated by glucose alone and the basal IRI. These in vivo studies suggest that KSG-504 has significant inhibitory effects both on the pancreatic exocrine and endocrine secretion stimulated by CCK, but has no effect on the exocrine secretion stimulated by secretin.

Animals↗

PubMed1996

["Vertigo" the fact analysis of clinical practice by ENT physicians of Chiba Prefecture by "send-out" questionnaires].

Despite the fact that vertigo has been one of the most frequent complaints encountered in daily practice in an ENT outpatient clinic, it is believed to be the most unwelcome subject for ENT physicians. The reasons are diverse; e.g., the understanding of vertigo is still a difficult task for most physicians and requires time-consuming multiple studies. However, answers to those questions, although speculated a posteriori, are yet to be substantiated. Therefore, we have analyzed the data obtained from multiple questionnaires that were addressed to ENT physicians practicing in Chiba Prefecture in November of 1993. However, those who work in publicly run hospitals were excluded from the study. The study included otorhinolaryngologists who were members of the Society of Otorhinolaryngology of Japan. We received filled questionnaire forms from 76 of 155 members (49%). The age ranged from 33 to 82 years (mean 55.8 years, 68 men and 8 women). From these questionnaires, it became apparent that physicians are not necessarily reluctant to see patients with vertigo. Instead, most ENT physicians appeared to be actively paying attention to this symptom and to be making efforts to approach its diagnosis and treatment. Although we are not certain if the data obtained here represent the majority of ENT physicians, the positive attitudes toward the patients with vertigo/dizziness would certainly encourage those of us who are interested in this particular symptom category.

Adult↗

PubMed1996

[Promotive factors of chronic subdural hematoma in relation to age].

To reveal the pathogenesis of chronic subdural hematoma (CSDH), 256 patients with CSDH over 1 year of age were studied in relation to various traumatic or nontraumatic promotive factors of CSDH including arachnoid cyst, implantation of a cerebrospinal fluid shunt, secondary cerebral atrophy, coagulopathies and past history of acute subdural hematoma or effusion. All patients were grouped according to decade of age. The incidences of associated promotive factors were individually analyzed in each group. The incidences of associated promotive factors in the 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th decades of life were 71%, 89%, 56%, 33%, 9%, 11%, 8%, 8% and 5%, respectively. Thus, they were divided into two groups; youth (1st to 4th decade: n = 34) and elder (5th to 9th decade: n = 222). The incidences of associated promotive factors were 62% and 8%, respectively (P < 0.001). Severity of head injury received was also evaluated in these two groups. In the youth group, 15 out of 34 patients (44.1%) had received severe head injuries with loss of consciousness, while in the elder group, only 22 out of 222 patients (9.9%) had received severe head injuries (P < 0.001). The analysis was repeated after each group was divided into two subgroups regarding the coexistence of promotive factors. Among the youth group, 13 patients had no promotive factors and 21 had one or more promotive factors. In those without any promotive factor, 9 out of 13 had received severe head injuries with loss of consciousness, while in those with promotive factors, 6 out of 21 had received severe head injuries. On the other hand, majority of the elder group had not received severe head injuries irrespective of whether patients had promotive factors or not. The present study revealed that majority of young CSDH patient had some promotive factors or severe head injuries with loss of consciousness, and that majority of patients aged over 40 years had no promotive factors and did not receive severe head injuries.

Adolescent↗

PubMed1996

Mycotic aneurysm of the internal iliac artery caused by Klebsiella pneumoniae.

Mycotic aneurysms are rarely caused by Klebsiella species. We describe a male patient with diabetes mellitus and alcoholism who developed a mycotic aneurysm of the right internal iliac artery complicated by the formation of a false aneurysm. Klebsiella pneumoniae was cultured from arterial blood. An extra-anatomic bypass (left external iliac artery to right common femoral artery) was performed with a successful excision of the aneurysm.

Aneurysm, Infected↗

PubMed1996

[Nucleotide sequences at intron 6 and exon 7 junction of fibroblast growth factor receptor 2 and rapid mutational analysis in Apert syndrome].

Apert syndrome, acrocephalosyndactyly Type I, is an autosomal dominant craniosynostosis comprising acrocephaly, facial dysmorphism and severe syndactyly of the hands and feet. Missense mutations at codons 252 and 253 at 5'-end on exon 7 of fibroblast growth factor receptor (FGFR) 2 have been identified in a large number of patients with Apert syndrome. In this study, nucleotide sequences on the intron 6 were determined by vector ligation-PCR and direct sequencing. Five DNA samples from sporadic Apert syndrome were examined by non-RI SSCP and direct sequencing using a primer pair of intron 6 and exon 7. All cases of the syndrome showed abnormal banding pattern in the SSCP and missense mutations from Ser to Trp at codon 252 of the FGFR2 gene. The non-RI SSCP and direct sequencing of the FGFR2 exon 7 from genomic DNAs may be a useful and rapid molecular means for clinical diagnosis of Apert syndrome.

Acrocephalosyndactylia↗

PubMed1996

[Frequent missense mutations of fibroblast growth factor receptor (FGFR) gene families in craniofacial syndromes in Japanese patients].

Craniofacial syndromes, including Crouzon syndrome, Pfeiffer syndrome, Jackson-Weiss syndrome, Apert syndrome and achondroplasia, have been indicated that syndromes were associated with mutations of fibroblast growth factor receptor (FGFR) gene families. In this report, seven Japanese patients with craniofacial syndromes, three Crouzon syndromes and four achondroplasias, were analyzed on FGFR2 and FGFR3 genes by non RI-SSCP (single strand conformation polymorphisms) and direct sequencing. Missense mutations of the FGFR3 exon 10, at codon 380 in two sporadic cases and codon 375 in two familial cases, were detected in all cases of achondroplasia. Mutations of the FGFR2 were noted in Crouzon and Apert syndromes. One of three Crouzon syndromes has a missense mutation at codon 342 on exon 9. Highly frequent mutations were clustered within some localized regions of the FGFR genes in craniofacial syndromes. Alterations in these receptors due to missense mutations would thus appear closely involved in pathogenesis of craniofacial syndrome. The non RI-SSCP and direct sequencing of the FGFR genes, shown in this report, may be an appropriate approach for diagnosis of these syndromes with extensive clinical application.

Base Sequence↗

PubMed1996

Frequency specificity of 80-Hz amplitude-modulation following response.

The usefulness of 80-Hz amplitude-modulation following response (AMFR) detected by phase coherence to predict the hearing threshold during sleep was evaluated in 90 ears of 53 children with hearing impairment. The threshold of 80-Hz AMFR at carrier frequency of 1,000 Hz and the threshold of auditory brainstem response (ABR) elicited by 1,000 Hz tone pips in children during sleep were compared with behavioral hearing threshold, which was determined by standard pure-tone audiometry or play audiometry. In 12 ears of 12 children with various patterns of hearing impairment, 80-Hz AMFR at different carrier frequencies were examined, and the threshold pattern was compared with the pure-tone audiogram to investigate the frequency specificity of 80-Hz AMFR detected by phase coherence. The mean and standard deviation of the difference between 80-Hz AMFR and pure-tone thresholds was 4.3 and 12.1 dB, respectively, and that between ABR and pure-tone thresholds was 6.6 and 14.2 dB, respectively. The threshold patterns of 80-Hz AMFR very closely resembled the corresponding audiogram patterns in all types of hearing impairment. The measurement of 80-Hz AMFR in children during sleep thus appeared to be more accurate in hearing prediction than that by ABR elicited with tone pips and to have a good frequency specificity.

Adolescent↗

PubMed1996

Immunohistochemical detection of CDK4 and p16INK4 proteins in cutaneous malignant melanoma.

p16INK4 gene, which encodes a specific inhibitor of cyclin-dependent kinase 4 (CDK4), has been recently reported as an important tumour suppressor gene. It is mapped to chromosome 9p21, which is frequently deleted or mutated in many tumour cell lines including malignant melanoma. Since the CDK4/cyclin D complex propels a cell to go through the G1 check point of the cell cycle, a critical phase of cell division, alteration of the p16INK4 gene could lead a cell to uncontrolled proliferation and malignant transformation. To clarify any role for p16INK4 and CDK4 proteins in the development of human malignant melanoma, we have examined, immunohistochemically, the expression of these two proteins in melanocytic neoplasms including 19 primary lesions of non-familial melanoma. Intense nuclear and/or cytoplasmic expression of the CDK4 protein was observed in 11 of 19 cases (58%) of melanoma. In contrast, virtually no nuclear or cytoplasmic staining for CDK4 protein was detected in 28 benign melanocytic naevi, including six Spitz naevi. Expression of p16INK4 protein was observed in three of 19 melanomas (16%) and in 17 of 28 benign naevi (61%). Inverse expression of CDK4 and p16INK4, at individual cell level, was detected in one case of melanoma. The present study suggests that CDK4 overexpression is characteristic for malignant melanoma, and probably reflects its autonomous accelerated cell proliferation. The expression rate of p16INK4 protein in malignant melanoma was lower than that in benign naevi, although the significance of p16INK4 deletion in melanoma development has not been definitely confirmed.

Carrier Proteins↗

PubMed1996

[Pulmonary malignant fibrous histiocytoma presenting as hemothorax].

A 39-year-old woman, who suffered from a sudden episode of severe left-sided back pain, was admitted to our hospital because of hemothorax. Chest CT scans revealed a mass extending from the left hilum to the posterior thoracic wall. The mass occluded the left pulmonary artery at the left main bronchus. Examination of a frozen section of a specimen obtained during a thoracotomy showed a sarcomatous tumor. A left pneumonectomy was then performed. Microscopic examination of a specimen revealed that the tumor was composed of spindle cells with cellular atypia and mitosis forming fascicles and storiform arrays. Malignant fibrous histiocytoma (storiform-pleomorphic pattern) was diagnosed. Chemotherapy was carried out six times during the year after surgery. No recurrence of the tumor has been seen during 20 months of follow-up.

Adult↗

PubMed1996

[Fatty acid metabolic disorder detected by 123I-BMIPP SPECT shortly after elective percutaneous transluminal coronary angioplasty].

UNLABELLED: Decreased or unchanged BMIPP uptake is often observed in the repeated SPECT imaging soon after successful angioplasty, although coronary flow remarkably recovers. To evaluate clinical significance of this phenomenon, 23 patients underwent BMIPP SPECT before elective PTCA (BM-1), soon after PTCA (72 hours, BM-2), and 3 months later (BM-3). SPECT imagings were divided into 7 segments and were semiquantitatively evaluated by 2 cardiologists in the blinded fashion. Decreased uptake at BM-2 compared with BM-1 was evaluated by comparing with stress Thallium-201 SPECT performed in the same schedule but on the different date (TI-1, 2, 3), ischemic manifestation at PTCA, and wall motion change of LVG. Patients with restenosis were excluded from this study. RESULTS: BM-2 showed decreased uptake in 14 (61%), unchanged in 2 (9%), and increased in 7 (30%) patients, while stress TI showed increased perfusion in all patients. Among 91 myocardial segments correspondent to PTCA vessels, 30 (33%) showed overt uptake reduction, and only 13 (14%) segments showed increased uptake. BM-2 uptake reduction was significantly associated with the absence of collateral artery (odds ratio, OR = 3.1, p <0.01), multi vessel disease (OR = 2.0, p = 0.01), total balloon inflating time (p <0.05), ST elevation on ECG (OR = 3.6, p = 0.01), chest pain during PTCA (OR = 3.1, p <0.1), while pre-dilatation by using small size balloon catheter prevented BM-2 uptake reduction (OR = 6.0, p = 0.01). Multiple logistic regression analysis showed that chest pain, balloon inflating time and pre-dilatation were independently associated with BM-2 uptake reduction. Three months after PTCA. the segments with BM-2 reduction had stress TI uptake similar to the segments without BM-2 reduction, however, they showed poorer recovery of BM-3 uptake and LV wall motion. CONCLUSION: BMIPP uptake reduction shortly after angioplasty was associated with ischemic manifestation and poor LV motion recovery, thus, it may be a sensitive representation of the stunned myocardium.

Aged↗

PubMed1996

Effects of the new calcium antagonist efonidipine hydrochloride on resting and exercise hemodynamics in patients with stable effort angina.

The action of efonidipine hydrochloride ((+/-)-2-[benzyl(phenyl)-amino]ethyl 1,4-dihydro-2,6-dimethyl-5-(5,5-dimethyl-2-oxo-1, 3,2-dioxaphosphorinan-2-yl)-4-(3-nitrophenyl)-3-pyridinecarboxy late hydrochloride ethanol, CAS 1110011-76-8, NZ-105) a new dihydropyridine calcium antagonist, on cardiac hemodynamics at rest and during exercise as well as plasma concentration and pharmacokinetic parameters were studied in 9 patients with angina pectoris. NZ-105 was administered 40 mg once daily for a week and cardiac hemodynamics parameters were measured at rest and during exercise using a bicycle ergometer before and after treatment. All patients showed anginal symptoms during exercise before treatment, while only 4 showed anginal symptoms during exercise after treatment. Improvement on electrocardiograms (ECG) (> 0.1 treatment mV) was detected in 4 out of 9, and NZ-105 was recognized to have an anti-anginal action. The mean plasma concentration of NZ-105 at the time was 14.5 ng/ml. At rest, reduction in blood pressure and decrease in total peripheral vascular resistance were observed, however, NZ-105 showed no effect on heart rate, cardiac index, pulmonary arterial pressure and central venous pressure. During maximum exercise, a decrease in total peripheral vascular resistance, reduction in pulmonary arterial pressure and central venous pressure, increasing tendency of left ventricular ejection fraction, and increase in cardiac index were observed. However, NZ-105 showed no effect on heart rate and blood pressure. Based on the results mentioned above, cardiac hemodynamics of NZ-105 during exercise, featured primarily, reduction of afterload and improvement of cardiac functional deterioration due to exercise. In conclusion, NZ-105 is useful in patients with ischemic cardiac diseases by improving hemodynamics and ECG findings during exercise in patients with effort angina.

Angina Pectoris↗

PubMed1996

Human blood lactate and ammonia levels after supramaximal uphill and downhill running.

The purposes of this study were 1) to confirm whether there is a difference in the levels of blood lactate and ammonia after supramaximal uphill and downhill running for the same short duration and 2) to examine the relationship between peak blood lactate levels and work/lean body mass (LBM), as well as the relationship between peak blood ammonia levels and work/LBM following supramaximal uphill and downhill running. Eight healthy, untrained male subjects performed supramaximal uphill and downhill running on a motor-driven treadmill for about 70 sec. Though there was a significant difference (p < 0.05) in running speed and work/LBM between supramaximal uphill and downhill running, no significant difference was found in exhaustion time or heart rate. Both the peak blood lactate and ammonia concentrations were significantly lower after downhill running than after uphill running (p < 0.05). Although there was no significant relationship between peak blood ammonia levels and work/LBM following either uphill or downhill running, significant linear relationships between the peak blood lactate levels and work/LBM were observed following uphill running (r = 0.74, p < 0.05) and downhill running (r = 0.72, p < 0.05). These results suggest that the differences in the blood lactate and ammonia concentration between supramaximal downhill and uphill running of the same duration may be due to the total recruitable muscle mass during exercise, and that peak blood lactate can be used as an index of anaerobic work capacity for untrained subjects under these running conditions.

Adult↗

PubMed1995

Direct evaluation of stereoselectivity of cancer esterases by polyacrylamide gel electrophoresis coupled with activity staining with chiral naphthyl esters.

Both enantiomers of alpha-naphthyl 2-phenylpropanoate (PhPr(ONap)), N-acetylalaninate (AcAla(ONap)), N-methoxycarbonylalaninate (MocAla(ONap)), N-methoxycarbonylvalinate (MocVal(ONap)), N-acetylprolinate (AcPro(ONap)), and N-(trifluoroacetyl)prolinate (TfaPro(ONap)) were prepared and used with Fast Blue RR salt for activity staining of esterases separated by polyacrylamide gel electrophoresis. Comparison of the band thicknesses stained with each enantiomer indicates stereoselectivity of the major esterase in that band. Several esterases in normal rat liver, rat hepatoma-derived cells, and mouse B16 melanoma showed alteration or inversion of stereoselectivity by the substrate change from MocAla(ONap) to MocVal(ONap) or from AcPro(ONap) to TfaPro(ONap). The stereoselectivity of the major esterases for MocVal(ONap) was reversed between the murine liver and the B16 melanoma enzymes. The present staining with chiral naphthyl esters is very effective for surveying rapidly the stereoselectivity of animal tissue and cancer esterases.

Animals↗

PubMed1995

Fine localization of low and high calcium dependent ATPase activities in the rat sciatic nerve.

We tried to demonstrate the electron microscopic histochemical localization of membrane Ca(2+)-ATPase activity in glutaraldehyde-fixed rat sciatic nerves. Although conventional glutaraldehyde fixatives containing impurities interfered with the reactivity of Ca(2+)-ATPase, this activity was successfully preserved in the tissues fixed with pure glutaraldehyde as well as in those fixed with paraformaldehyde. In unmyelinated nerve fibers, an ATPase activity depending on 10 mM CaCl2 was detected on the whole external surface of Schwann cell plasma membranes. In myelinated fibers, this activity was localized on the surface of Schwann cell outer loops at the paranodal region of Ranvier nodes and on the axonal membrane at the nodal region. Another activity depending on 0.1 mM CaCl2 was demonstrated on the axolemma of unmyelinated fibers. These results indicated that there may be two types of Ca(2+)-ATPase activities showing high and low affinity to calcium ions localized in peripheral nerve systems in a different manner between myelinated and unmyelinated fibers.

Animals↗

PubMed1995

Effects of various dopamine uptake inhibitors on striatal extracellular dopamine levels and behaviours in rats.

In vivo central effects of some dopamine uptake inhibitors were evaluated in both brain microdialysis and behavioural studies in rats, and compared with their in vitro affinities to dopamine uptake sites. IC50 values of GBR12909 (1-[2- bis(4-fluorophenyl)methoxy]ethyl]-4-(3- phenylpropyl)piperazine), diclofensine, mazindol, amfonelic acid and nomifensine for inhibiting 1 nM [3H]GBR12935 (1-[2-(diphenylmethoxy)ethyl]-4-(3-phenylpropyl)piperazine) binding to rat striatal membrane were 7.0, 36, 81, 187 and 290 nM, respectively. In the brain microdialysis study, dopamine levels in the striatal dialysates were increased to 16.3- (GBR12909), 14.1- (nomifensine), 4.8- (diclofensine) and 1.9-fold (amfonelic acid) the respective basal levels 40-60 min after i.p. administration (0.1 mmol/kg) and thereafter decreased slowly but remained at the elevated levels for a further 3 h, while mazindol gradually increased dopamine levels though less pronouncedly than others (1.7-fold 200 min after administration). Remarkable and comparable stereotyped behaviours (licking and forepaw treading) were continuously observed at least for 3 h after administration of GBR12909, nomifensine and amfonelic acid, while stereotypies induced by diclofensine and mazindol were moderate and marginal, respectively. In vivo potencies of dopamine uptake inhibitors to increase the extracellular dopamine levels in the striatum tended to correlate with their in vitro affinities to dopamine uptake sites except in the case of nomifensine, and correlated significantly with their potencies to induce stereotyped behaviours except in the case of amfonelic acid. Based on these findings, pharmacological characteristics of these dopamine uptake inhibitors are discussed.

Animals↗

PubMed1995

Water structural changes at the proton uptake site (the Thr46-Asp96 domain) in the L intermediate of bacteriorhodopsin.

Fourier transform infrared spectra of the L intermediate of light-adapted bacteriorhodopsin were examined for recombinant proteins with amino acid substitutions at Thr46 and Asp96. Two O-H stretching vibrational bands of water, at 3607 and 3577 cm-1, change into stronger H-bonding states in L of the wild type. Thr46-->Val substitution abolished these bands in spite of the fact that [3-18O]threonine-labeling did not shift them, indicating that they correspond to coordination of the water with Thr46. The two water bands were restored, although with changed frequencies, by an additional Asp96-->Asn substitution in Thr46-->Val/Asp96-->Asn. A single Asp96-->Asn substitution abolished the 3607 cm-1 band. Thus, Asp96 also takes part in structural changes in water. The perturbations of these water molecules in the L intermediate displayed a weak correlation with the ratio of intensity change in the two vibrational bands of the Schiff base mode at 1312 and 1301 cm-1 and the rate for the deprotonation of the Schiff base at the L-to-M reaction of the photocycle. We find, therefore, that the water molecules in the cytoplasmic Asp96-Thr46 domain, which comprises the site of proton uptake after formation of the M intermediate, undergo structural changes in the L intermediate already. These changes are transmitted to the extracellular domain and affect interaction of the Schiff base with Asp85, that is far removed from this region.

Aspartic Acid↗

PubMed1995

Gene trap capture of a novel mouse gene, jumonji, required for neural tube formation.

A mouse mutation, termed jumonji (jmj), was generated by a gene trap strategy. Expression of the trapped gene (jmj gene), as monitored by X-gal staining, was detected predominantly at the midbrain-hindbrain boundary and in the cerebellum, depending on the stage of development. All embryos homozygous for the jmj mutation died before embryonic day 15.5. Some, but not all, of the homozygotes developed an abnormal groove in a region just anterior to the midbrain-hindbrain boundary on the neural plate at embryonic day 8-8.5 and showed a defect in neural tube closure in the midbrain region. Analyses of jmj cDNA revealed that the jmj gene is novel, conserved among vertebrates, and disrupted by vector insertion in the jmj homozygotes. The amino acid sequence deduced from the cDNA shared a portion of significant homology with human retinoblastoma-binding protein RBP-2 and with a putative protein encoded by human gene XE169 that escapes X-chromosome inactivation. These results suggest that jmj gene is essential for normal morphogenesis of the neural tube.

Amino Acid Sequence↗

PubMed1995

Difference between cancer cells and the corresponding normal tissue in view of stereoselective hydrolysis of synthetic esters.

This study has aimed at taking information necessary for design of anticancer prodrugs modified with chiral acyl group, especially about the effect of chirality of the acyl group on its enzymic removal in specific cells. Thus, 13 species of chiral esters were synthesized and stereoselectivity in their enzymic hydrolysis was investigated with six cancer cell lines, solid tumors, and the corresponding normal tissues. Cultured cancer cells from rat liver, pancreas, and muscle hydrolyzed the R enantiomer of (+/-)-ethyl 2-methoxy-2-phenylacetate (3c) more preferentially than its antipode, whereas this stereoselectivity was reversed in the reaction by homogenate of the corresponding normal tissue of rat. The difference in stereoselectivity between cancer cells and normal tissue was also found in the hydrolysis of other esters including those of actual anticancer agents, p-hydroxyaniline mustard and 5-fluorouridine. The investigation was expanded to real tumor to show that the degree of stereoselectivity or the hydrolytic activity was significantly different between a human brain tumor and its surrounding normal tissue for such substrates as (+/-)-ethyl 2-phenoxypropanoate and N-trifluoroacetylphenylalaninate. The esterases of rat liver cancer cells (Anr4) and normal rat liver gave different band patterns in active staining after gel electrophoresis. The enzymes were fractionated by ion exchange column chromatography and then tested on their stereoselectivity against (+/-)-3c. Comparison of the results and electrophoretograms of the fractions suggests that esterases with different stereoselectivity are expressed in different ways by normal and cancer cells. These results show that stereoselectivity in enzymic hydrolysis of some synthetic chiral esters is different between cancer and normal cells, leading to the possibility that specific activation of ester-type anticancer prodrugs in cancer cells would be controlled by the chiral structure of the acyl group.

Animals↗