[A Case Report of Uterine Metastasis Four Years after Breast Surgery for Breast Cancer]

We report a case of uterine metastasis of the breast cancer. The patient was diagnosed with invasive ductal carcinoma of the breast and underwent partial right mastectomy and sentinel lymph node biopsy. Tamoxifen was administered as adjuvant endocrine therapy. Four years after the surgery, she had irregular genital bleeding, and was referred to our hospital for cytological diagnosis of uterine cancer. Postoperative pathological diagnosis showed uterine metastasis of breast cancer, and it was decided to treat the recurrence of breast cancer with aromatase inhibitors and CDK4/6 inhibitors, a molecular targeted therapy. The patient has been progression-free for 5 months.

[A case of rectum metastasis of breast cancer]

A 53-year-old woman visited the hospital of this study complaining of constipation. Colonoscopy revealed a circumferential tumor with severe stenosis, and a computed tomography scan showed neoplastic lesions in the rectum and right breast area. Histology was poorly differentiated adenocarcinoma, requiring differentiation between type 4 and metastatic rectal cancer. Additional immunohistochemical tests were performed and a rectal metastasis of breast cancer diagnosis was made. Hormonal therapy was effective and the tumor volume was significantly reduced. Rectal metastasis of breast cancer is said to be rare. However, in the case of patients diagnosed with breast cancer or with a history of breast cancer, considering the possibility of gastrointestinal metastasis using histopathological examination is important.

Modified Cyclodextrin Sulphates(mCDS11) have Potent Inhibitory Activity against HIV and High Oral Bioavailability

Modified cyclodextrin sulphate (mCDS) in which lipophilic groups were introduced to cyclodextrin sulphate (CDS) was synthesized and proved more inhibitory to the replication of HIV-1 and HIV-2 than CDS or dextran sulphate (DS). The anti-coagulant activity of mCDS was lower than that of DS. Cyclodextrin phosphate (CDP) showed anti-HIV activity similar to that of CDS, and its anti-coagulant activity was even lower than that of mCDS. Flow cytometric analysis suggested that the mechanism of the anti-HIV-1 action of CDS, mCDS, and CDP is based on inhibition of HIV-1 binding to the cells. The peak blood concentration after oral administration of mCDS11(potassium tris[6-benzylthio-6-deoxy]-β-cyclodextrin hexadecasulphate) to rabbits was about 1000 times higher than the concentration showing anti-HIV activity. The retention time in the blood was also long (blood half-life: 4 h). These results point to the potential usefulness of oral mCDS administration in the prophylaxis and/or therapy of HIV infections.

Sequence analysis of a pea comb locus on chicken chromosome 1

To facilitate gene identification, this study aimed to narrow the scope of the genome region affecting chicken comb type by using two bird populations. First, an F2 resource population was generated by crossing Japanese game fowl (Shamo; pea comb, P/p and P/P) with White Plymouth Rock (single comb, p/p). Comb types of the 240 F2 offspring produced by an F1 intercross between eight males and 57 females were segregated at a ratio of 3:1 (pea:single). The pea comb locus was mapped to a chromosomal region on Gallus gallus chromosome 1 that was flanked by microsatellite markers MCW0112, MCW0019 and ABR521. The second population (five-generation, n=1300 animals) was derived from a cross between Shamo and Rhode Island Red (single comb, p/p) that had been genotyped for additional polymorphic single nucleotide polymorphisms and microsatellite markers within this region through development of chicken draft sequences. To close some gaps in these draft sequences, we constructed a bacterial artificial chromosome contig and sequenced it using the shotgun sequencing technique. Chickens selected from pedigrees in these populations were grouped by inheritance of a P or p haplotype at the locus constructed by the additional markers. Finally, this locus was fine-mapped to roughly 60 kb based on the association of haplotypes and comb types. Chicken genome sequences suggest that the most likely polymorphism responsible for the pea comb locus is a duplicated sequence and that the sex determining region Y-box 5 gene, one predicted gene and one expressed sequence tag in a critical region may be associated with the duplicated sequence.

Down-regulation of p73 correlates with high histological grade in Japanese with breast carcinomas

BACKGROUND

p73, a homologue of p53, has been located at chromosome 1p36-33, a region of frequently observed loss of heterozygosity in breast cancers. The objective of the present study was to investigate the function of p73 in Japanese with breast cancers.

METHODS

Sixty Japanese patients with breast cancer were assessed by polymerase chain reaction single strand confirmation polymorphism analysis and direct sequencing to detect the p73 allele. p73 mRNA levels were also determined in 40 out of 60 patients by reverse-transcriptional polymerase chain reaction.

RESULTS

We analyzed the entire open reading frame of the p73 gene by polymerase chain reaction single strand confirmation polymorphism and sequencing, and failed to identify any mutations of p73 in the encoding regions detected. Loss of heterozygosity of p73 was infrequent and only found in 9% of breast carcinomas. We revealed a few polymorphisms with a frequency of 13% - 29%, which had been reported previously. Down-regulation of p73 mRNA expression was observed in tumor tissues in comparison to the normal breast tissues. A significant inverse correlation was found between p73 transcripts and high histological grade, suggesting that down-regulated p73 expression could be related to poor prognosis in those patients.

CONCLUSION

Our results suggest that p73 may serve as a tumor suppressor gene and its expression plays a role in tumorigenesis in Japanese patients with breast cancer.

PDZK1 regulates organic anion transporting polypeptide Oatp1a in mouse small intestine

Recent studies indicate that various members of the organic anion transporting polypeptide (OATP) family are expressed on apical membranes of the small intestine. In the present study, we investigated possible interaction of Oatp with the PDZ protein PDZK1 in mouse small intestine, using [³H]estrone-3-sulfate (E3S) as a typical substrate. After intraduodenal administration, the level of [³H]E3S appearing in the portal vein of pdzk1 gene knockout (pdzk1(-/-)) mice was much lower than that in wild-type mice. Lower intestinal absorption of [³H]E3S in pdzk1(-/-) mice was confirmed in Ussing-type chamber experiments, which showed smaller uptake of [³H]E3S from the apical side in intestinal tissues of pdzk1(-/-) mice compared with wild-type mice. The kinetics and inhibition profile of [³H]E3S uptake in the Ussing-type chamber were similar to those in HEK293 cells stably expressing Oatp1a5, suggesting involvement of Oatp1a5 in [³H]E3S uptake. Immunoreactivity to anti-Oatp1a antibody was colocalized with PDZK1 in the small intestine of wild-type mice, whereas apical localization of Oatp1a protein was reduced in pdzk1(-/-) mice. An immunoprecipitation study revealed physical interaction of PDZK1 with Oatp1a. Thus, PDZK1 appears to act as an adaptor for Oatp1a. This is the first demonstration of a regulatory protein directly interacting with small-intestinal OATP.

[Therapeutic effects of vinorelbine-based chemotherapy--retrospective study of 65 patients with metastatic or relapsed breast cancer]

PATIENTS

The subjects were 65 stage IV or relapsed breast cancer patients who received vinorelbine monotherapy or combination therapy at Fukushima Medical University between May 2002 and November 2006.

METHOD

Chemotherapy was divided into the following 3 groups Vinorelbine monotherapy (group A), Trastuzumab combination therapy (group B), MMVC (mitomycin C, methotrexate, vinorelbine and cyclophosphamide) therapy(group C).

RESULTS

There were 33 patients in group A, 15 patients in group B, and 17 patients in group C. The percentage of patients who had received more than 3 prior chemotherapy regimens were 69. 7% in group A, 66. 7% in group B, and 82. 4% in group C. No complete responses were observed. Partial responses was observed 6 patients in group A, 5 patients in group B, and 2 patients in group C. Overall response rate was 18. 2% in group A, 33. 3% in group B, and 11. 8% in group C. Clinical benefit rate was 24. 2% in group A, 46. 7% in group B, and 23. 5% in group C. The median overall survival time was 267, 522, and 275 days in group A, B, and C respectively.

DISCUSSION

Vinorelbine-based chemotherapy was considered as a new treatment option for patients with metastatic or relapsed breast cancer. It is necessary to examine the use at the early stage or more to obtain a high response rate and duration of response.

A comparison of the production of reactive oxygen species by suspended particulate matter and diesel exhaust particles with macrophages

Oxidative stress has emerged as a pivotal mechanism that underlies the toxic pulmonary effects of suspended particulate matter (SPM). Experimental evidence shows that redox-active transition metals, redox-cycling quinoids, and polycyclic aromatic hydrocarbons (PAHs) contained in SPM act synergistically, producing reactive oxygen species (ROS). The direct production of superoxide anion and the damaging hydroxyl radical has been studied in aqueous and dimethyl sulfoxide (DMSO) suspensions of SPM both with and without H2O2; however, no study has reported on the release of ROS from ingesting macrophages with SPM. We investigated the time course of the ability to induce lucigenin-dependent chemiluminescence (CL) from human monocyte-derived macrophages exposed to SPM, carbon black particles, and diesel exhaust particles (DEP). We also examined hydroxyl radical generation from the same experimental system using the 2-deoxy-d-robse method. We found an increase of CL for SPM, but not for carbon black particles or for DEP. Hydroxyl radical generation was observed in both SPM and DEP, but the release from DEP was more frequent than that from SPM. These results suggest that certain components of SPM are important in the response of ROS from ingesting macrophages with SPM, and that those components are discharged from SPM into the atmosphere.

Mapping of the Recessive White Locus and Analysis of the Tyrosinase Gene in Chickens

An F(2) chicken population of 265 individuals, obtained from an intercross between the Japanese Game (colored plumage) and the White Plymouth Rock (the recessive white) and genotyped for microsatellite markers, was used for determining the locus of the gene responsible for the recessive white plumage phenotype in chickens. Two hundred twenty-five markers were mapped in 28 linkage groups. Linkage analysis revealed that the recessive white gene was mapped to chromosome 1. Detailed analysis using additional markers uncovered a significant linkage between 2 new markers, mapped to the flanking region of the tyrosinase gene, which is associated with skin and plumage color. The sequence of the tyrosinase gene was investigated in recessive white chickens and colored chickens. There were no obvious differences in the tyrosinase gene exons between the recessive white chicken and the colored chicken. However, sequence analysis of tyrosinase intron 4 in the recessive white chicken revealed a presence of an insertion of an avian retroviral sequence. The White Plymouth Rock and the F(2) generation with white plumage were identified as homozygous carriers of the retroviral sequence. Expression of the normal transcript containing exon 5 was substantially decreased in the recessive white chicken compared with the colored chicken. Some abnormal tyrosinase gene transcripts were expressed in the skin of the White Plymouth Rock: reverse transcription PCR products amplified from exon 3 to intron 4 and from retroviral sequence 3' long terminal repeat to exon 5. Based on these results, it was confirmed that an avian retroviral sequence insertion in the tyrosinase gene was the cause of recessive white phenotype in chickens.

Synthesis and properties of G-quartet oligonucleotide-HIV-1 tat peptide conjugate

Zintevir is a single strand DNA that forms an intramolecular quadruplex structure and shows potent anti-human immunodeficiency virus type 1 (HIV-1) activity. Zintevir was discovered as a potent inhibitor for HIV-1 integrase. Recently, the primary molecular target of Zintevir, however, was shown to be the HIV-1 gp120. In fact, in our previous study, Zintevir was shown to inhibit the only processes of the viral adsorption and the entry into the cell. This result suggests that Zintevir is not able to penetrate through the cell membranes. Therefore, we designed and synthesized the complex of D-17mer with HIV-1 tat peptide that has the cell membrane permeability.

[Two cases of HIV-1 acute infection with antibody negative by immunochromatography method]

We found two cases of HIV-1 acute infection, confirmed by nucleic amplification test (NAT) and/or RT-PCR, with HIV-1 antibody negative by immunochromatography (IC) method but weakly positive by particle agglutination (PA) test. These cases suggested that IC method was less sensitive than PA test in the detection of acute infections. It is necessary to execute the post counseling that considers the possibility of the acute infection in public health centers and testing places where IC method is used for the screening test. It is also important to recommend taking the following re-examination after a certain period to a person who seems to have had a chance of infection in a short time before testing.

Novel method of inactivation of human immunodeficiency virus type 1 by the freeze pressure generation method

It has been reported that high-pressure (over 600 MPa) treatment at room temperature inactivates human immunodeficiency virus type 1 (HIV-1), and it has recently been shown that the high pressure generated by the expansion of water due to freezing (freeze pressure generation method, or FPGM) has an inactivating effect on bacteria and fungi. In this study, we examined the effects of treatment by FPGM on HIV-1. A sturdy vessel filled with water and securely closed with a lid was kept at 0 degrees C to -30 degrees C. High pressures of 200 MPa and 250 MPa were generated at -20 degrees C and -30 degrees C, respectively. When T-cell-tropic and macrophage-tropic laboratory strains of HIV-1 were kept at -10 degrees C, the virus infectivity decreased to approximately 1/100, and was completely lost at -20 degrees C and -30 degrees C. Four T-cell-tropic and four macrophage-tropic laboratory strains and clinical isolates of HIV-1 became completely inactivated at -30 degrees C. Treatment by FPGM at -20 degrees C to -30 degrees C reduced HIV-1 reverse transcriptase activity to approximately one tenth. In addition, treatment by FPGM at -20 degrees C was found to destroy the ability of HIV-1 to bind to CD4+ cells. In conclusion, this study showed that treatment by FPGM at -20 degrees C to -30 degrees C destroyed the infectivity of a wide range of HIV-1 strains, and suggested that the mechanisms of HIV-1 inactivation were the reduction in viral enzyme activity and the loss of the cell-binding ability of a viral envelope protein.

[A study on enterovirus infection in Osaka prefecture --comparison with virus isolation and RT-PCR amplifying viral protein 1 region]

Detection of viral genomes with RT-PCR, which amplifies viral protein 1 region, as well as virus isolation was performed on 860 patients (996 specimens) who had been suspected for enterovirus (EV) infection in Osaka Prefecture from April 2003 to Jury 2004. The viral positive rates of the clinical materials, combining above two procedures, were as follows: 48.2% from the feces, 38.3% from the throat swabs, and 18.0% from the cerebrospinal fluids. The positive rate by the clinical diagnosis indicated that herpangina was the highest at 44.7%, while encephalitis was the lowest at 13.4%. Out of the all specimens, the viral positive rate of RT-PCR varied from 22.3 to 24.7%, while that of virus isolation was 15.6%. The total viral positive rate of both procedures combined was 29.8%. Since the detection of EV by RT-PCR amplifing viral protein 1 region was more rapid than virus isolation and superior in detection of coxsackie group A virus, RT-PCR is an effective procedure for diagnosis of herpangina.

Higher frequency of premature stop codon mutations at vpu gene of human immunodeficiency virus type 1 CRF01_AE compared with those of other subtypes

Our previous study demonstrated the anti-apoptosis function of the human immunodeficiency virus type 1 (HIV-1) vpu gene product in normal CD4+ T lymphocytes. In this study, using sequences obtained from the HIV sequence database, we compared vpu sequences from 184 preparations of various subtypes of HIV-1 from diverse geographical regions. Our analysis revealed that CRF01_AE isolates had premature stop codon mutations at the vpu gene at a much higher rate (36%) than other subtypes (0-9%). The premature stop codon mutations in vpu existed mostly at two amino acid residues: the methionine initiation codon and the boundary between the transmembrane (TM) and cytoplasmic domains. The mutations at the latter site were more often detected in CRF01_AE. The higher mutation rates at vpu in CRF01_AE were confirmed by sequence comparison of polymerase chain reaction products newly obtained directly from the DNA extracted from peripheral blood mononuclear cells (PBMCs), but not from the RNA from the plasma, in CRF01_AE- and subtype B-infected individuals. This finding may indicate the possibility that the more abundant population of HIV-1 CRF01_AE is able to induce apoptosis in CD4+ T lymphocytes than the populations of other subtypes.

Anti-HIV-1 activity and mode of action of mirror image oligodeoxynucleotide analogue of Zintevir

Zintevir is an oligonucleotide analogue, which has the phosphorothioate modification at both termini, that forms a K(+)-induced quadruplex structure and shows potent anti-human immunodeficiency virus (HIV)-1 activity. We synthesized the non-modified analogue (D-17mer) of Zintevir and its enantiomer (L-17mer), and compared their anti-HIV-1 activity and molecular mechanism of action. Although L-17mer forms the exact mirror image quadruplex structure of D-17mer, which has a very similar structure with Zintevir, L-17mer showed comparable anti-HIV-1 activity with Zintevir. The results obtained by the time-of-addition experiments and the immunofluorescence binding assay strongly suggest that the primary molecular target of L-17mer is the viral gp120 envelope protein as well as Zintevir, regardless of their reciprocal chirality.

Anti-HIV-1 activity of L-DNA quadruplex

Zintevir is a DNA 17mer that forms a quadruplex and shows strong anti-human immunodeficiency virus (HIV)-1 activity. The quadruplex formation is thought to be essential for the anti-HIV-1 activity of Zintevir. We synthesized the enantiomer of Zintevir and evaluated its structure and anti-HIV-1 activity. The results showed that the enantiomer has anti-HIV-1 activity comparable to that of Zintevir although it forms the mirror image quadruplex structure of Zintevir.

Mutational analysis of TGF-beta type II receptor, Smad2, Smad3, Smad4, Smad6 and Smad7 genes in colorectal cancer

Transforming growth factor-beta(TGF-beta) is known to play an important role in controlling embryonal development, cell proliferation and homeostasis. The purpose of this study is to elucidate the involvement of the TGF-beta pathway in colorectal carcinogenesis. DNA was extracted from 100 patients with colorectal cancer. Then, all coding regions of the TGF-beta type II receptor (TRII) and the genes for Smad2, Smad3, Smad4, Smad6, and Smad7 were analyzed by PCR-SSCP and direct sequencing. Also, a LOH analysis of 18q21, where the Smad2 and Smad4 genes are located, was performed. We detected 11 cases of frameshift mutation in the TRII gene (11%) and 5 cases of point mutations in the Smad4 gene (5.0%); LOH at 18q21 was detected with 33% frequency. No abnormalities were found in the genes for Smad2, Smad3, Smad6, and Smad7. These results suggest that the abnormalities of TRII and Smad4 play an important role inhibiting TGF-beta signaling in colorectal carcinogenesis.

HIV-1 integrase inhibitory substances from Coleus parvifolius

For the purpose of discovering anti-HIV-1 agents from natural sources, water and EtOH extracts of 50 Thai plants were screened for their inhibitory activity against HIV-1 integrase (IN), an enzyme essential for viral replication. Of these plants, an EtOH extract of Coleus parvifolius Benth. (aerial parts) showed potent activity against HIV-1 IN with an IC50 value of 9.2 microg/mL. From this extract, 11 compounds were isolated and identified as luteolin 5-O-beta-d-glucopyranoside (1), luteolin (2), luteolin 7-methyl ether (3), luteolin 5-O-beta-d-glucuronide (4), 5-O-beta-d-glucopyranosyl-luteolin 7-methyl ether (5), rosmarinic acid (6), rosmarinic acid methyl ester (7), daucosterol (8), a mixture of alpha- and beta-amyrin (9, 10) and phytol (11). Of these compounds, rosmarinic acid methyl ester (7), rosmarinic acid (6), luteolin (2) and luteolin 7-methyl ether (3) exhibited inhibitory activities against HIV-1 IN with IC50 values of 3.1, 5.0, 11.0 and 11.0 microM, respectively. Among rosmarinic acid derivatives, the HIV-1 IN inhibitory activity increased in turn for a dimer (IC50 = 5.0 microM), a trimer (IC50 = 1.4 microM), and a tetramer (IC50 = 1.0 microM).

Synthesis and evaluation of anti-HIV-1 and anti-HSV-1 activities of 4H-[1,2,4]-triazolo[1,5-a]pyrimidin-5-one derivatives

In a one pot procedure, 18 compounds of 7-(substituted phenyl)-2-substituted-6,7-dihydro-4H-[1,2,4]triazolo[1,5-a] pyrimidin-5-one derivatives (16-33) have been synthesized. 3(5)-Amino-5(3)-substituted-1,2,4-triazole derivatives (7-12) were used as synthomes which were cyclo-condensed by fusion with substituted methyl cinnamate esters (13-15) to afford the target compounds (16-33). In an effort to develop new non-nucleoside antiviral agents, compounds 16-33 were evaluated for their anti-HIV-1 and anti-HSV-1 activities. Complete inhibition of the proliferation of HIV-1 viruses was achieved by compounds 22, 23 and 24 at concentrations of 25, 25 and 50 micrograms/ml, respectively. 7-Phenyl-2-(n-pentyl)-6,7-dihydro-4H-[1,2,4]triazolo[1,5-a]pyrimidin-5-one (19) exhibited potential activity against HSV-1 with 88% reduction in the viral plaques. The suggested marked specificity of this class of compounds as anti-HIV-1 and HSV-1 agents is discussed.

The role of posterior guidances under the altered anterior guidance

In five subjects, bilateral condylar movement was assessed during lateral excursions with different tooth guidance angles without changing the intercuspal position. Statistical analysis of anova (P < 0.01) revealed that when the incisal path angle became steeper than the natural tooth guidance, distances of the non-working side condyle paths (centre of condyle) decreased significantly, while distances of the working side condyle paths (centre of condyle) remained unchanged. Directions of the working side condyle paths were random, while directions of the non-working side condyle paths remained stable. By analysing six points around the centre of the condyle, it was not possible to confirm any affect on the working side condyle movement by changing the tooth guidance angle. It was revealed that the non-working side condyle had an 'active' role during lateral excursions, and that the working side condyle moved as a result of mandibular movement that was changed because of a steepening of the incisal path angle during lateral excursions. This suggests the possibility that the working side condyle movements were affected 'passively' by altering the tooth guidance.

A novel substance purified from Perilla frutescens Britton inhibits an early stage of HIV-1 replication without blocking viral adsorption

Pf-gp6, a 6 kDa anti-degranulation glycoprotein purified from the extract of Perilla frutescens, was examined for its antiviral activity against HIV-1 and HIV-2 in vitro. HIV-1-induced cytopathic effect and proviral DNA synthesis were inhibited in the presence of Pf-gp6. The 50% inhibitory concentrations of Pf-gp6 for various HIV-1 strains, including clinical isolates and CCR5-using (R5) HIV-1, ranged between 1.3 and 71.0 microg/ml, depending on the combination of viral strain and host cell. Furthermore, Pf-gp6 did not directly inactivate infectious viral particles. A time-of-addition experiment revealed that Pf-gp6 lost its activity before zidovudine but after the CXCR-4 antagonist AMD3100 during the early stage of viral infection. Although the pinpoint target of Pf-gp6 remains to be elucidated, it may interfere with a step between viral entry and reverse transcription.

Anti-human immunodeficiency virus-type 1 activity of constituents from Juglans mandshurica

Three naphthalene glycosides (1-3), four flavonoids (4-7), and two galloyl glycosides (8-9) were isolated from the stem-bark of Juglans mandshurica (Juglandaceae). Their structures were determined by chemical and spectral means, including to 2D-NMR (COSY, HMQC, and HMBC) experiments. Amongst the isolated compounds, taxifolin (4) showed the most potent HIV-induced cytopethic activity against MT-4 cells with complete inhibitory concentration (IC100) value of 25 microg/ml and maximum cytotoxic concentration (CC100) value of above 100 microg/ml. However, naphthalene glycosides (1-3), flavonoids (5-7), and galloyl tannins (8-9) were inactive against anti-HIV-1 activity.

Inhibitory effects of triterpene-azidothymidine conjugates on proliferation of human immunodeficiency virus type 1 and its protease

The conjugates of some dicarboxylic acid hemiesters of triterpenes which show potent inhibition against human immunodeficiency virus type 1 protease (HIV-1 PR) with a reverse transcriptase inhibitor azidothymidine (AZT) or anti-HIV alkaloid FK 3000 were prepared, and their inhibitory activities were investigated against HIV-induced cytopathic effects (CPE) and HIV-1 PR. Most of the triterpene-AZT conjugates showed potent anti-HIV activity as well as moderate to potent PR inhibitory activity, though AZT itself showed no PR inhibitory activity at all. However, the triterpene-FK 3000 conjugates showed neither PR inhibitory activity nor anti-HIV activity.

Ability to induce p53 and caspase-mediated apoptosis in primary CD4+ T cells is variable among primary isolates of human immunodeficiency virus type 1

Infection with human immunodeficiency virus type 1 (HIV-1) is associated with dramatic depletion of CD4(+) T cells, the major HIV-1-induced pathogenesis. Apoptosis has been suggested to play an important role for the T cell depletion and a number of mechanisms have been proposed for the apoptosis in T cells. Here, we compared the levels for apoptosis induction in primary peripheral blood mononuclear cells (PBMCs) among several laboratory strains and primary isolates of the HIV-1 subtypes B and E. The results showed that apoptosis in infected PBMCs, preferentially in CD4+ T cell population, became detectable around the time for virus production by flow cytometric terminal transferase dUTP nick end labeling (TUNEL) technique and staining with the nuclear dye Hoechst 33342. The abilities to induce apoptosis in PBMCs were highly variable in individual isolates. The increase of p53 protein in infected PBMCs, which was initiated before virus production, was observed in infected PBMCs and the levels of p53 protein were almost proportional to the rates of the isolates to induced apoptosis. The cells infected and cultured in the presence of Z-VAD-FMK had significantly decreased cell mortalities, indicating that activated caspases also played a significant role in the apoptosis. Thus, HIV-1-induced apoptosis in primary T cells was accompanied by the p53 protein and caspase activation at varied levels in primary isolates.

Inhibition of cytopathic effect of human immunodeficiency virus type-1 by various phorbol derivatives

Forty-eight derivatives of phorbol (9) and isophorbol (14) were evaluated for their inhibition of human immunodeficiency virus (HIV)-1 induced cytopathic effects (CPE) on MT-4 cells, as well as their activation of protein kinase C (PKC), as indices of anti-HIV-1 and tumor promoting activities, respectively. Of these compounds, the most potent inhibition of CPE was observed in 12-O-tetradecanoylphorbol 13-acetate (8) and 12-O-acetylphorbol 13-decanoate (6). The former also showed the strongest PKC activation activity, while the latter showed no activity at 10 ng/ml. Both activities were generally observed in those phorbol derivatives with an A/B trans configuration, but not in the isophorbol derivatives with an A/B cis configuration. Acetylation of 20-OH in the phorbol derivatives significantly reduced the inhibition of CPE, as shown in 12-O-, 20-O-diacetylphorbol 13-decanoate (6a) (IC100=15.6 microg/ml) vs. compound 6 (IC100=0.0076 microg/ml), and 12-O-tetradecanoylphorbol 13,20-diacetate (8a) (IC100=15.6 microg/ml) vs. 12-O-tetradecanoylphorbol 13-acetate (8) (IC100=0.00048 microg/ml), except in the case of 12-O-decanoylphorbol 13-(2-methylbutyrate) (4) and phorbol 12,13-diacetate (9c). The reduction of a carbonyl group at C-3 abruptly reduced the inhibition of CPE, as observed in 3beta-hydroxyphorbol 12,13,20-triacetate (9f) (IC100=500 microg/ml) vs. phorbol 12,13,20-triacetate (9d) (IC100=62.5 microg/ml). Although 8 was equipotent in the inhibition of CPE, and activation of PKC, both activities were abruptly decreased by the acetylation of 20-OH and methylation of 4-OH [as in 8a and 4-O-methyl-12-O-tetradecanoylphorbol 13,20-diacetate (8b), respectively]. On the other hand, its positional isomer (12-O-acetylphorbol 13-tetradecanoate (8c) showed neither activities. The removal of a long acyl group in 8 led to a substantial loss of both activities, as shown in phorbol 13-acetate (9b). Of the 12-O-acetyl-13-O-acylphorbol derivatives, the highest inhibition of CPE was observed in 6, which has a dodecanoyl residue at C-13. Both an increase and decrease in the number of fatty acid carbon chains resulted in significant reduction of the inhibition of CPE.

Screening of Chinese and Mongolian herbal drugs for anti-human immunodeficiency virus type 1 (HIV-1) activity

Water and methanol extracts of 30 Chinese and Mongolian medicinal plants were tested for their human immunodeficiency virus type-1 (HIV-1) inhibitory activity. Of the 60 extracts, 23 showed anti-HIV activity. Bioassay-guided fractionation of one of the most active extracts, the methanol extract of the root tuber of Stephania cepharantha, led to the isolation of two alkaloids, aromoline and FK-3000 as potent inhibitory substances. They completely inhibited the cytopathic effects of HIV-1 on MT-4 cells at 31.3 and 7.8 microg/mL, respectively.

Resting CD4(+) T cells with CD38(+)CD62L(+) produce interleukin-4 which contributes to enhanced replication of T-tropic human immunodeficiency virus type 1

A significant increase in the CD38(+) population among T lymphocytes has been observed in human immunodeficiency virus type 1 (HIV-1)-infected carriers. We previously reported a higher replication rate of T-tropic HIV-1 in the CD4(+)CD38(+)CD62L(+) than CD38(-) subset under conditions of mitogen stimulation after infection. Here, we revealed a similarly high susceptibility in the CD38(+) subset on culture with conditioned medium containing Th2 cytokine, interleukin (IL)-4 that was produced endogenously from this subset on stimulation with mitogen or anti-CD3 antibody for 3 days. The contribution of IL-4 to the upregulated production of virus in the CD38(+) subset was confirmed by culture of this subset with recombinant human IL-4. In contrast, the rate of replication in the CD38(-) subset was not augmented in the conditioned medium from either subset or with IL-4. However, there were no differences in the surface expression of IL-4 receptor or HIV-1 receptors CD4 and CXCR4 between the two subsets. Thus, the CD4(+)CD38(+)CD62L(+) subset comprises a specific cell population secreting endogenous Th2 cytokine that contributes to the efficient production of T-tropic HIV-1 through upregulation at a certain stage of the viral life cycle, probably after the adsorption step.

Effect of size of man-made and natural mineral fibers on chemiluminescent response in human monocyte-derived macrophages

Fiber size is an important factor in the tumorigenicity of various mineral fibers and asbestos fibers in animal experiments. We examined the time course of the ability to induce lucigenin-dependent chemiluminescence (CL) from human monocyte-derived macrophages exposed to Japan Fibrous Material standard reference samples (glass wool, rock wool, micro glass fiber, two types of refractory ceramic fiber, refractory mullite fiber, potassium titanium whisker, silicon carbide whisker, titanium oxide whisker, and wollastonite). We determined how fiber length or width might modify the response of cells. We found that the patterns of time-dependent increase of CL (sigmoid type) were similar for each sample except wollastonite. We observed a strong correlation between geometric-mean length and ability to induce CL in seven samples > 6 microm in length over the time course (largest r(2) = 0.9760). Although we also observed a close positive correlation between geometric-mean width and the ability to induce CL in eight samples < 1.8 microm in width at 15 min (r(2) = 0.8760), a sample of 2.4 microm in width had a low ability to induce CL. Moreover, the relationship between width and the rate of increase in ability to induce CL had a negative correlation at 30-60 min (largest r(2) = 0.7473). Our findings suggest that the release of superoxide from macrophages occurs nonspecifically for various types of mineral fibers depending on fiber length.

Inhibitory effects of Korean plants on HIV-1 activities

In the search for novel anti-human immunodeficiency virus type 1 (anti-HIV-1) agents from natural sources, 49 MeOH extracts of Korean plants were screened for their inhibitory effects against RNA-dependent DNA polymerase (RT) and ribonuclease H (RNase H) activities of HIV-1 reverse transcriptase and HIV-1 protease, and anti-HIV-1 activity. Regarding the HIV-1 reverse transcriptase, Agrimonia pilosa (whole plant), Cornus kousa (stem and leaf), Limonium tetragonum (root) and Mallotus japonicus (stem) showed significant inhibitory activity on RT activity with 50% inhibitory activity (IC(50)) of 8.9, 6.3, 7.5 and 11.9 microg/mL, respectively, whereas Agrimonia pilosa was also active against RNase H activity (IC(50) = 98.4 microg/mL). Four plants, namely Agrimonia pilosa (whole plant), Atractylodes japonica (root), Clematis heracleifolia (whole plant) and Syneilesis palmata (whole plant), were appreciably active (<35%) against recombinant HIV-1 protease at a concentration of 100 microg/mL. Crinum asiaticum var. japonicum (root) showed significant anti-HIV-1 activity (ED(50) = 12.5 microg/mL) with a favourable SI value of 16.

Analysis of organic esters of plasticizer in indoor air by GC-MS and GC-FPD

The aim of this study was to assess the performance of a method of analyzing organic esters of plasticizer in indoor air by sampling air in a charcoal tube and extracting the esters in toluene using a gas chromatography-mass spectrometer (GC-MS) and flame photometric detector (FPD). An internal standardization method was used for the GC-MS measurement of phthalate esters, whereas an external calibration method was employed to determine the levels of phosphate esters by FPD. The instrumental detection limit, the instrumental lower limit of determination, and the blank and method detection limits were also determined. Mean recoveries of phthalate esters from the charcoal tube were 97.9-115%. Mean recoveries of phosphate esters were lower but reproducible. Recoveries of the esters from indoor air were generally greater than 80%. For all the compounds, no significant breakthrough was detected up to 100 microg. Thus, indoor organic esters could be accurately determined in the range of 0.6 x 10(-3)-23 microg/m3 by the procedure presented here. Preliminary analysis of the organic esters indicated that exposure to phthalate esters via indoor air inhalation could constitute a significant contribution to total daily intake.

Low or no antibody responses to human immunodeficiency virus type 1 Nef in infected carriers with subtype E, in contrast to subtype B that showed antibodies preferentially recognizing subtype-specific Nef epitopes

The viral accessory gene product Nef has been shown to play an important role in human immunodeficiency virus type 1 (HIV-1)-induced pathogenesis. Only little information is available regarding the differences in the host immune responses against Nef protein and its function in vivo among different subtypes of HIV-1. In the present study, we showed marked differences in the immune responses to Nef protein between subtypes B and E. The amino acid sequence in subtype E Nef showed 72% homology with that in subtype B. Most murine monoclonal antibodies obtained by immunization with subtype B or E Nef protein showed cross-reactivity with both Nef proteins (80 and 67%, respectively). Next, we focused on the immune responses among infected Japanese and Thai individuals. Subtyping of the individuals into B and E was carried out by enzyme-linked immunosorbent assay (ELISA) using synthetic peptides corresponding to the V3 loop representing the principal neutralizing domain. Most of the sera from these individuals reacted strongly with Gag p24 proteins derived from subtypes B and E at similar levels. However, the immune responses among these individuals to Nef protein were markedly different. Some subtype B-infected Japanese and Thai individuals (40 and 35%, respectively) showed higher levels of anti-Nef antibodies, although these antibodies preferentially recognized epitopes specific to subtype B. On the other hand, most of the subtype E-infected Japanese and Thai individuals showed low or no antibody responses to Nef proteins. Thus, immune responses to Nef were markedly different between subtypes B- and E-infected carriers, suggesting different function(s) for Nef in AIDS pathogenesis. Further, vaccine design must take into account the different subtypes of HIV-1.

[Evaluation of antiretroviral chemotherapy based on the profile of virus isolation from HIV-1 infected individuals]

It is well-known that the biological characteristics of HIV-1 persistently infected in the host have often changed into a rapid growth in vitro, T-cell line tropism and marked syncytium inducing (SI) ability accompanied by the progress of clinical stages from AC to ARC or AIDS. We have developed a follow-up diagnostic test using the clinical markers based on the virus phenotypes mentioned above, and reported that the test was significantly useful for determining the clinical status of HIV infected individuals. Recently, highly active antiretroviral therapy (HAART) was introduced into HIV-1 chemotherapy, and has been reported to be a markedly effective treatment for HIV infected individuals. In this study, we carried out an investigation to see whether the follow-up diagnosis was useful even after introducing the HAART in Japan in 1997. The results by the laboratory diagnosis on 139 HIV infected individuals who were clinically observed over a long period showed that the positive rate of virus isolation and MT-4 cell tropism in the isolates during the two years between 1997 and 1998 were significantly lower than that of the nine years from 1988 to 1996 before the implementation of HAART. In addition, we obtained data that the effect of HAART reflects the biological profiles of virus isolation more than the CD4+ T cell counts. These results suggest that data of clinical examination using virus isolation as a parameter are useful not only for predicting the development of AIDS but also for evaluating the effects of HAART, particularly in patients showing no association between the CD4+ T cell counts and the plasma viral load.

The chemiluminescent response from human monocyte-derived macrophages exposed to various mineral fibers of different sizes

The aims of the present work were to quantify ability to induce lucigenin-dependent chemiluminescence (CL) from 6-9 day-old human monocyte-derived macrophages exposed to various mineral fibers, and to examine the relationship between ability to induce CL and fiber size. All fiber samples induced the CL response from the cells. The relationship between the number of fibers administered and the CL response was examined on all fiber samples by linear regression. The slope of the regression line supplies an approximation of the ability to induce CL. A strong increased correlation between geometric-mean length of fibers and ability to induce CL was observed for the seven fiber samples more than 6 microns in length (r = 0.9895). Geometric-mean width and the ability to induce CL showed no correlation. However, among the two fiber samples having a similar length distribution (RF2, RF3), the wider width sample (RF3, 2.4 microns) demonstrated lower ability to induce the CL than the narrower width sample (RF2, 1.1 microns). The present method enabled comparison of ability to induce lucigenin-dependent CL from human monocyte-derived macrophages for various mineral fibers with different sizes. Our findings suggested the possibility that ability to induce O2- production increased with fiber length, when fibers are longer than approximately 6 microns.

[Detection of genotypic and phenotypic drug-resistant HIV-1 in patients receiving antiretroviral therapy]

We have analyzed the sequences of HIV-1 reverse transcriptase and protease genes in peripheral blood mononuclear cells obtained from patients receiving antiretroviral therapy to evaluate the drug resistance-associated mutations. Of 84 HIV-1-infected individuals treated with reverse transcriptase inhibitors, 43 (51.2%) have been found to carry amino acid substitutions predicted to acquire drug-resistances. One to 3 mutations at amino acid residues reported to be associated with protease inhibitor-resistance were detected in more than 80% of protease inhibitor-naive patients. However, these pre-existing mutations did not seem to raise a real resistance after the initiation of therapy with protease inhibitors. Phenotypic resistance assay was performed with 6 clinical isolates to compare with genotypic resistance. In most of the cases, phenotype was correlated with genotypic changes, however, two strains which were isolated from patients having no experience of chemotherapy showed a decrease in susceptibility to several drugs without any resistance-related mutations detected in their genes. Taken together, determination of phenotypic resistance is necessary, especially when a newly-infected patients starts antiviral therapy.

Quantitative assessment of regional myocardial blood flow using oxygen-15-labelled water and positron emission tomography: a multicentre evaluation in Japan

Recently, a method has been proposed for the quantitative measurement of regional myocardial blood flow (MBF) using oxygen-15-labelled water and positron emission tomography (PET). A multicentre project was organized with the intention of evaluating the accuracy of this method, particularly as a multicentre clinical investigative tool. Each of seven institutions performed PET studies on more than five normal volunteers following a specified protocol. The PET study included a transmission scan, a 15O-carbon monoxide static scan and a 15O-water dynamic scan, thereby yielding MBF values which should have been independent of the spatial resolution of the PET scanner employed. Fifty-three subjects (aged 20-63 years, mean+/-SD 36+/-12 years) were studied at rest, and 31 of these subjects were also studied after dipyridamole in five institutions. Inter-institution consistency and intra-subject variation in MBF values were then evaluated. MBF averaged for all subjects was 0.93+/-0.34 ml min(-1) g(-1) at rest and 3.40+/-1.73 ml min(-1) g(-1) after the administration of dipyridamole, and the flow reserve (defined as the ratio of the two MBF values) was 3.82+/-2.12; these values are consistent with previous reports. Resting MBF values were significantly correlated with the heart rate-blood pressure product (RPP) (y=0.31+6.56E-5x, P<0.010), and RPP was in resting MBF observed in all institutions was well explained by the age-dependent RPP. No significant difference was observed in resting MBF among the institutions. Except in one institution, no significant difference was seen in dipyridamole MBF or myocardial flow reserve. No significant difference was found among the myocardial segments. Regional variation was reasonably small in five institutions, but was not acceptable in two institutions, which was attributed to the scanner performance. These observations suggest that the 15O-water PET technique is useful for a multicentre clinical study if the PET scanner can provide time-activity data with good count statistics.

Anti-HIV-1 phorbol esters from the seeds of Croton tiglium

Five phorbol diesters, together with three known ones, were isolated from a MeOH extract of the seeds of Croton tiglium, and their structures were determined by spectroscopic methods and selective hydrolysis of acyl groups. These compounds were assessed for their abilities to inhibit an HIV-induced cytopathic effect (CPE) on MT-4 cells and to activate protein kinase C (PKC) associated with tumor-promoting action. 12-O-Acetylphorbol-13-decanoate and 12-O-decanoylphorbol-13-(2-methylbutyrate) effectively inhibited the cytopathic effect of HIV-1 [complete inhibitory concentration (IC100) values of 7.6 ng/ml and 7.81 microg/ml, and minimum cytotoxic concentration (CC0) value of 62.5 and 31.3 microg/ml, respectively]; however, 12-O-acetylphorbol-13-decanoate showed no activation of PKC at concentrations of 10 and 100 ng/ml. 12-O-Tetradecanoylphorbol-13-acetate (TPA) was found to be not only the most potent inhibitor of HIV-1-induced CPE (IC100 value of 0.48 ng/ml), but also the most potent activator of PKC (100% activation at 10 ng/ml).

The effect of Kana literacy acquisition on the speech segmentation unit used by Japanese young children

Three experiments were undertaken to investigate whether young children's segmentation units would change as they learned to read kana letters, which represent morae (subsyllabic rhythmic units). The first 2 experiments used a vocal-motor segmentation task to examine whether 4- to 6-year-olds preferred to segment spoken words containing the special syllables CVN, CVQ, or CV: into syllables or into morae. The third experiment used a target monitoring task for CVN to examine whether children's detection of the target syllable in a series of words would vary depending on the moraic constitution of the target and the moraic-syllabic status of the word initial in which the target was embedded. Results indicated that the children's conscious segmentation of words, except for those having a geminate stop consonant (CVQ), developed from being a mixture of syllable- and mora-based to being predominantly mora-based as they learned to read kana letters. The tendency toward mora-based segmentation was also found in the target monitoring task, which required segmentation at a less conscious level.

HIV-1 protease inhibition and anti-HIV effect of natural and synthetic water-soluble lignin-like substances

Water-soluble lignin extracted from natural sources and dehydrogenated polymers of p-coumaric acid and ferulic acid inhibited HIV-1 protease activity. The dehydrogenated polymers, which are thought to be model compounds for lignin, were synthesized and fractionated into four ranges of molecular mass by ultra-filtration: i.e., over 30 kDa, 30-10 kDa, 10-1 kDa and 1 kDa-500 Da. All of these fractions had HIV-1 protease inhibitory activity. The anti-HIV-1 effect of the smallest mass fractions of the dehydrogenated polymers (1 kDa-500 Da) was also tested, and it was found that these fractions inhibited the replication of HIV-1 in MT-4 cells.

Anti-HIV-1 activity of myo-inositol hexaphosphoric acid (IP6) and myo-inositol hexasulfate(IS6)

It is known that polysulfates have some anti-HIV-1 activity. We investigated the anti-HIV-1 activity of myo-inositol hexaphosphoric acid (IP6) and myo-inositol hexasulfate(IS6), low molecular weight carbohydrates. IP6 and IS6 inhibited the replication of HIV-1 in a T cell line as well as that of a freshly isolated strain in peripheral blood mononuclear cells. Neither substance inhibited HIV-1-induced giant cell formation, but addition of IS6 when infecting cells with HIV-1 inhibited the replication of HIV-1. Neither substance inhibited HIV-1 reverse transcriptase activity in vitro and no influence on late stage replication was noted. Although the mechanisms of IP6 and IS6 action remain unclear, it can be speculated that they act on HIV-1 early replicative stage. Although it is not possible to develop IP6 and IS6 themselves as anti-AIDS drugs, studies of these anti-HIV agents might be expected to provide seed for eventual production of superior drugs for AIDS treatment.

12-O-acetylphorbol-13-decanoate potently inhibits cytopathic effects of human immunodeficiency virus type 1 (HIV-1), without activation of protein kinase C

Through bioactivity-guided fractionation, eight phorbol diesters, including five new ones (1-5), were isolated from the seeds of Croton tiglium collected in Egypt. 12-O-Acetylphorbol-13-decanoate (6) and 12-O-decanoylphorbol-13-(2-methylbutyrate) (4) potently inhibited the HIV-1-induced cytopathic effect on MT-4 cells (IC100 values of 7.6 ng/ml and 7.81 micrograms/ml, and CC0 values of 62.5 micrograms/ml and 31.3 micrograms/ml, respectively) without activating protein kinase C.

Primary small cell carcinoma of the esophagus with achalasia in a patient in whom pro-gastrin-releasing peptide and neuron-specific enolase levels reflected the clinical course during chemotherapy

We report a case of primary small cell carcinoma of the esophagus in a patient with achalasia in whom pro-gastrin-releasing peptide (ProGRP) and neuron-specific enolase (NSE) levels were measured. Although chemotherapy markedly reduced the size of the primary tumor and lymph node metastases, it had no effect on liver metastases. The tumor marker levels decreased after chemotherapy as the primary tumor and lymph node metastases decreased in size, and they increased as the liver metastases enlarged. However, there was a discrepancy between the levels of ProGRP and NSE during the patient's clinical course. We demonstrate the usefulness of measuring ProGRP and NSE levels to assess the effect of chemotherapy in patients with esophageal small cell carcinoma.

Sevoflurane exposure time and the neuromuscular blocking effect of vecuronium

PURPOSE

To determine the effect of sevoflurane exposure time on the duration of vecuronium neuromuscular blockade.

METHODS

In 40 adult patients anesthesia was induced with 1.5-2 mg x kg(-1) propofol and 3-5 microg x kg(-1) fentanyl and the trachea was intubated without the aid of muscle relaxant. Patients were randomized into four groups of 10. In group 1, 0.05 mg x kg(-1) vecuronium was administered with N2O and anesthesia was maintained by propofol infusion and fentanyl. Vecuronium was administered with sevoflurane 2% in 30 patients, commencing at the same time (group 2) and at 30, and 60 min after sevoflurane (groups 3, 4). Adductor pollicis force of contraction to train-of-four ulnar nerve stimulation was recorded. Times from vecuronium injection to 95%, maximal block, and recovery times to 25% recovery were recorded.

RESULTS

There were no differences in times to 95% and maximal block in the four groups. Recovery times were longer in groups 3 and 4 than in groups 2 and 1 (P < 0.01). Times to 5% recovery were 15.0 +/- 3.7, 17.8 +/- 4.8, 28.2 +/- 9.9, and 29.5 +/- 9.5, and to 25% recovery were 22.3 +/- 5.2, 27.2 +/- 6.4, 42.3 +/- 16.3, and 50.5 +/- 16.4 in groups 1, 2, 3, and 4 respectively. No differences were found between group 1 and group 2 nor between group 3 and group 4.

CONCLUSION

Sevoflurane produced time-dependent potentiation of vecuronium. After 30 min exposure, 25% recovery was prolonged by 89% and after 60 min by more than 100% compared with the control group.

Pitch accent in spoken-word recognition in Japanese

Three experiments addressed the question of whether pitch-accent information may be exploited in the process of recognizing spoken words in Tokyo Japanese. In a two-choice classification task, listeners judged from which of two words, differing in accentual structure, isolated syllables had been extracted (e.g., ka from baka HL or gaka LH); most judgments were correct, and listeners' decisions were correlated with the fundamental frequency characteristics of the syllables. In a gating experiment, listeners heard initial fragments of words and guessed what the words were; their guesses overwhelmingly had the same initial accent structure as the gated word even when only the beginning CV of the stimulus (e.g., na- from nagasa HLL or nagashi LHH) was presented. In addition, listeners were more confident in guesses with the same initial accent structure as the stimulus than in guesses with different accent. In a lexical decision experiment, responses to spoken words (e.g., ame HL) were speeded by previous presentation of the same word (e.g., ame HL) but not by previous presentation of a word differing only in accent (e.g., ame LH). Together these findings provide strong evidence that accentual information constrains the activation and selection of candidates for spoken-word recognition.

Inhibitory effects of Sudanese plant extracts on HIV-1 replication and HIV-1 protease

Forty-eight methanol and aqueous extracts from Sudanese plants were screened for their inhibitory activity on viral replication. Nineteen extracts showed inhibitory effects on HIV-induced cytopathic effects (CPE) on MT-4 cells. The extracts were further screened against HIV-1 protease (PR) using an HPLC assay method. Of the tested extracts, the methanol extracts of Acacia nilotica (bark and pods), Euphorbia granulata (leaves), Maytenus senegalensis (stem-bark) and aqueous extracts of A. nilotica (pods) and M. senegalensis (stem-bark) showed considerable inhibitory effects against HIV-1 PR. Inhibitory principles were isolated from M. senegalensis and their activities were also discussed.

Characterization of human immunodeficiency virus type 1 resistant to modified cyclodextrin sulphate (mCDS71) in vitro

Drug resistance of human immunodeficiency virus type 1 (HIV) to modified cyclodextrin sulphate (mCDS71) has been analysed with respect to both the in vitro appearance of resistance to the compound and the mechanism of the acquisition of resistance. Resistant strains could be obtained in all three strains (NL432, KK-1 and A018) tested after serial passages in MT-4 cells with a gradual increase of the concentration of mCDS71. Cross-resistance both to mCDS71 and dextran sulphate 8000 was observed. As a result of sequencing analysis of the gp120 V3-C5 region of resistant strains, the mechanism of resistance can be explained in several ways: (i) substitution of sugar chain-binding amino acids, N and S; (ii) three to five amino acid deletion in V4 loop; and (iii) several mutations in V3 and V4 regions. The real cause of the resistance may be a combination of these three mechanisms. The results suggest that the target of mCDS71 is relatively widely distributed on the viral surface glycoprotein.