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Biomedical subjects

A Adachi

Publications and source records attributed to A Adachi.

At least 199 records · Page 11Linked to original sources
PubMed1993

Integration is essential for efficient gene expression of human immunodeficiency virus type 1.

A mutant of human immunodeficiency virus type 1 which carries a frameshift insertion in the integrase/endonuclease region of pol gene was constructed in vitro. Upon transfection into cells, although this mutant exhibited a normal phenotype with respect to expression of gag, pol, and env genes and to generation of progeny virions, no replication-competent virus in CD4-positive cells emerged. An assay for the single-step replication of a defective viral genome dependent on trans complementation by rev protein was established and used to monitor the early phase of viral infection process. Viral clones with a mutation in the vif, vpr, or vpu gene displayed no abnormality in the early phase. In contrast, the integrase mutant did not direct a marker gene expression after infection. Together with an observation that the mutant lacked the ability to integrate, these results indicated that the integration was required for efficient viral gene expression and productive infection of human immunodeficiency virus type 1.

Cell Line↗
PubMed1993

Cell-dependent requirement of human immunodeficiency virus type 1 Vif protein for maturation of virus particles.

A highly sensitive single-round infection assay using a bacterial chloramphenicol acetyltransferase was developed to analyze an early stage of human immunodeficiency virus type 1 replication. By a combination of transfection and single-round infection assay, a virus with a vif mutation, depending on host cells from which the virus was derived, was demonstrated to be defective at the early phase of infection cycle. Analysis of viral proteins synthesized in cells indicated that incorporation of the Env surface protein into virions of the vif mutant, again in a cell-dependent way, was greatly restricted. Taken together, it is concluded that the Vif protein acts through modulation of the Env protein in the virions, directly or indirectly, to enhance viral infectivity in a certain cell type.

Acquired Immunodeficiency Syndrome↗
PubMed1993

[Prediction of performance status after pneumonectomy].

To predict performance status (P.S.) following pneumonectomy, patients with lung carcinoma underwent pre-surgical pulmonary function tests with spirometry and unilateral pulmonary artery occlusion test (UPAO test). Between 1980 and 1991, twenty-nine patients who had survived more than six months after surgery were selected for the study. These patients were divided into two groups according to P.S. measured at six months after surgery: 16 patients with P.S. 0 to 1 were in Group A, and 13 patients with P.S. 2 to 3 were in Group B. The results of the following tests obtained prior to surgery were compared for the two groups to predict post-surgical P.S.; vital capacity (VC), VC/m2, forced expiratory volume in 1 second (FEV1.0), FEV1.0/m2, predicted VC/m2 and predicted FEV1.0/m2 calculated with residual pulmonary segments, mean pulmonary arterial pressure (PPA) before UPAO and 15 minutes after UPAO, total pulmonary vascular resistance (TPVR) before and during UPAO, and rate of changes in PPA and TPVR. Results obtained were as follows: Group B demonstrated significantly higher TPVR (p < 0.05) before the UPAO, PPA (p < 0.05) and TPVR (p < 0.002) during UPAO, and rate of change in TPVR (p < 0.02) than those in Group A. There were no significant differences between the two groups for other test results. From these results, lowering of post-surgical P.S. might be predicted when the TPVR during UPAO was 350 dyne.sec.cm-5/m2 or more.

Blood Pressure↗
PubMed1993

Women with human immunodeficiency virus infection and abnormal Papanicolaou smears: a prospective study of colposcopy and clinical outcome.

OBJECTIVE: To determine the effect of human immunodeficiency virus (HIV) infection on colposcopic and histologic findings and clinical outcome in women who have abnormal Papanicolaou smears. METHODS: We conducted a prospective study of women with abnormal Papanicolaou smears from among those participating in a longitudinal study of HIV infection, human papillomavirus infection, and genital neoplasia. Women with squamous intraepithelial lesions (SIL) on blindly interpreted Papanicolaou smears were referred for colposcopy and standard gynecologic care. Colposcopic and histologic findings were correlated with cytology, and differences between HIV seropositives and seronegatives were analyzed. RESULTS: Thirty-eight of 48 women referred underwent colposcopy, of whom 36 (94.7%) had colposcopic or histologic findings no more severe than those suggested by Papanicolaou smear. Seventeen of 25 HIV seropositives (68%) had cervical or vaginal condyloma or neoplasia, compared with three of 13 seronegatives (23%) (odds ratio [OR] 7.1, 95% confidence interval [CI] 1.5-33.0). Among seropositives, seven (28%) had cervical intraepithelial neoplasia (CIN) grade II or III; ten (40%) had cervical or vaginal condyloma, CIN I, or both; and eight (32%) had no vaginal or cervical SIL. There was no case of invasive carcinoma. Seven seropositives (28%) had or developed multicentric disease, compared with no seronegatives (P = .07). Follow-up ranged at 3-37 months and showed that all three treated seronegative women and five of ten treated seropositive women had normal examinations. Three seropositive patients had persistent disease without progression, and two had progression of condyloma. No CIN II, CIN III, or invasive carcinoma was seen during follow-up. CONCLUSIONS: Among women seropositive for HIV who had SIL on a Papanicolaou smear, colposcopic and histologic findings were predicted reliably by the cytologic smear. Rapid progression of CIN after standard gynecologic care for early genital lesions was not seen.

Acquired Immunodeficiency Syndrome↗
PubMed1993

[A case report: multiple liver metastasis of gastric cancer responding to intraarterial infusion of MTX and 5-FU].

In a 63-year-old male patient with gastric cancer having multiple liver metastases, the metastatic lesions responded well to postoperative staggered intraarterial infusion therapy with MTX and 5-FU. The intraarterial infusion therapy was administered once a week. A total of 5 courses of this therapy produced marked regression of liver metastases and remarkable necrosis. The effect was thus rated as PR. The patient is healthy and has been successfully rehabilitated. His dose is oral 5-FU (200 mg x 2).

Adenocarcinoma↗
PubMed1992

Genetic characterization of simian immunodeficiency virus isolated from an African mandrill.

We constructed an infectious molecular clone of simian immunodeficiency virus from an African mandrill (SIVMND). Upon transfection, this clone directed the production of progeny virus particles infectious to and cytopathic for CD4+ human leukemia cells. Thirteen frameshift proviral mutants with an alteration in the eight open reading frames of SIVMND were generated by recombinant DNA techniques, and were analyzed biologically and biochemically. While mutations in the structural genes gag, pol, and env abolished viral growth and induction of cytopathology, mutants of the vif, vpr, and nef genes were fully biologically active. Of the tat and rev mutants, only one rev mutant grew in CD4+ cells with delayed kinetics. In reporter-based transient expression systems, transactivation potentials of the tat and rev mutants were evaluated. A mutant lacking 2nd coding exon of tat gene exhibited tat activity similar to that of the wild type clone. The infectious rev mutant was partially defective for rev gene activity.

Amino Acid Sequence↗
PubMed1992

Effect of hepatic portal infusion of water on water intake by water-deprived rats.

To determine whether or not hepatoportal osmoreceptive (or sodium-receptive) signals participate in the control of drinking, we examined the effects of portal infusion of water, 0.9% saline, and 1.8% saline on water intake by water-deprived rats. Infusion was started 0.5 h prior to the end of the water deprivation period for 3.5 h at a rate of 52 microliters/min through either a portal or a jugular catheter. After 24-h water deprivation, water intake was measured successively for 24 h without food. As a result of the water infusion tests, water intake of the portal infusion group was significantly less than that of the jugular infusion group during and after the infusion. Portal infusion of neither 0.9% nor 1.8% saline affected the water intake compared to similar infusion into the jugular vein. It is concluded that hypotonic stimulation of the hepatoportal osmoreceptor suppresses water intake in water-deprived rats. On the contrary, isotonic or hypertonic stimulation does not produce any change of water intake.

Animals↗
PubMed1992

Functional analysis of biologically distinct genetic variants of simian immunodeficiency virus isolated from a mandrill.

We examined the biological properties of two infectious clones of a simian immunodeficiency virus, SIVMND, which were designated as pMD121 and pMD122. Upon transfection into CD4-negative cells, pMD122 generated virions much less efficiently than pMD121. Likewise, the growth kinetics in CD4-positive cells of virus derived from pMD122 were remarkably delayed relative to those of virus from pMD121. The cytocidal activity of the MD122 virus was also low. A series of recombinant clones were constructed from pMD121 and pMD122 to determine the sequence responsible for the low virulence of the MD122 virus. The genetic determinant in pMD122 responsible for its properties was mapped to within a region (316 base pairs) encompassing the tat, rev, and env coding sequences. Sequence analysis revealed that the two clones differed by only one nucleotide in this region. A nucleotide substitution G (pMD121) to T (pMD122) altered an arginine codon to a serine codon in the first tat coding exon. Transient transfection experiments showed that the tat activity of pMD122 was about twofold less than that of pMD121. These findings indicate that small differences in tat activity can have a dramatic effect on the biological behavior of SIVMND.

Amino Acid Sequence↗
PubMed1992

Functional classification of simian immunodeficiency virus isolated from a chimpanzee by transactivators.

In reporter-based transient expression systems, we characterized simian immunodeficiency virus from a chimpanzee (SIVCPZ), with special reference to the human immunodeficiency virus type 1 (HIV-1). SIVCPZ was not equally activated by tat and rev transactivators derived from representative primate lentiviruses. HIV-1 alone activated SIVCPZ to the full extent in both tat and rev assays. The tat and rev gene products of SIVCPZ, as well as those of HIV-1, efficiently transactivated the other viruses. These results indicate that SIVCPZ is identical to HIV-1 with regard to the compatibility of tat and rev gene activities among four subgroups of primate lentiviruses.

Amino Acid Sequence↗
PubMed1992

Immunoelectronmicroscopic differentiation of linear IgA bullous dermatosis of adults with coexistence of IgA and IgG deposition from bullous pemphigoid.

BACKGROUND: The differentiation between linear IgA bullous dermatosis (LABD) and bullous pemphigoid (BP) is sometimes difficult in patients who have both IgA and IgG deposition in a linear pattern at the basement membrane zone. OBJECTIVE: We address whether two cases of acquired subepidermal blistering disease with coexistence of IgA and IgG deposition in a linear pattern at the basement membrane zone are LABD or BP. METHODS: The two cases were investigated by immunoelectron microscopy and compared with two typical cases of LABD. RESULTS: In both cases, the deposition of IgA and IgG was ultrastructurally localized below the lamina densa in close association with anchoring fibrils, as was seen in two cases of typical LABD. CONCLUSION: These findings indicate that our two cases of acquired blistering disease with co-existence of IgA and IgG deposition are LABD, rather than BP.

Aged↗
PubMed1992

SIV/HIV recombinants and their use in studying biological properties.

A series of chimeric clones between human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency viruses (SIV) were constructed. Viability of the recombinant viruses was dependent on the position of recombination. Infectious chimeric viruses between HIV-1 and SIVAGM (isolated from an African green monkey) and those between HIV-1 and SIVMAC (isolated from a rhesus monkey) were examined for host cell tropism. Viral determinants that restrict the replication of SIVAGM in human MT-4 cells and that of HIV-1 in macaque monkey peripheral blood mononuclear cells (PBMC) mapped to the 5' half of the virus genome. One HIV-1/SIVMAC chimera which contained the HIV-1 env gene was shown to replicate in macaque PBMC in vitro and to infect macaque monkeys in vivo. This HIV-1/SIVMAC chimera will be useful for a variety of AIDS pathogenesis and vaccine studies.

Animals↗
PubMed1992

Sequences responsible for efficient replication of simian immunodeficiency virus SIVMND in cells of the monocyte/macrophage lineage.

We determined the susceptibility of monocytic cell lines to infection with viral strains derived from two infectious clones of simian immunodeficiency virus isolated from a mandrill. One of the strains, which replicates poorly in T cell lines, was found to grow more rapidly than the other in these cells. The viral determinant for this property was genetically mapped within the env gene encoding a surface protein. Six amino acid substitutions identified appeared to be located outside of the domains corresponding to human immunodeficiency virus type 1 env functional domains such as the CD4-binding and V3 loop regions.

Animals↗
PubMed1992

Production of feline immunodeficiency virus in feline and non-feline non-lymphoid cell lines by transfection of an infectious molecular clone.

An infectious molecular clone of the TM1 strain of feline immunodeficiency virus (FIV) was transfected into each of one feline (CRFK), two simian (COS and Vero) and two human (SW480 and HeLa) non-lymphoid cell lines, and virus production was assayed on feline T lymphoblastoid MYA-1 cells by monitoring reverse transcriptase activity. Infectious virus was produced in CRFK, Vero and HeLa cells, but not in COS and SW480 cells. When the basal promoter activity of the FIV long terminal repeat (LTR) was examined in these cell lines by using a chloramphenicol acetyltransferase assay, the activity correlated with the virus production in each cell line. Furthermore, when the activity of the FIV LTR was compared with those of three primate lentivirus LTRs, the highest activity in all the cell lines examined was produced by the LTR of simian immunodeficiency virus from African green monkey (SIVAGM), suggesting that it has a wide expression range. In COS and SW480 cells, the activity of the FIV LTR was much lower than that of the SIVAGM LTR. These results indicate that, whereas the primary block to FIV infection of certain cells may occur at the cell surface, the FIV LTR may also participate in controlling virus replication, as an intracellular mechanism.

Animals↗
PubMed1992

Drug-resistant Staphylococcus aureus contamination in the ward environment.

A total of 282 strains of Staphylococcus were isolated from University Hospital ward environment from April 1991 to January 1992 and drug-susceptibility tests were performed. The main isolates were 84 strains of S. epidermidis (30%), 65 strains of S. aureus (23%), and 58 strains of S. haemolyticus (21%). One hundred and thirty-six strains of all staphylococci (48%) and 13 of 65 strains of S. aureus (20%) were methicillin (DMPPC)-resistant. The DMPPC-resistant strains of S. aureus were multiple drug-resistant to three to seven antibiotics; ampicillin. cephaloridine, cephametazole, tetracycline, erythromycin, gentamicin, and methicillin, while the DMPPC-susceptible strains were resistant to less than two drugs. These results indicate that this routine testing, along with testing of the anterior nares of the medical staff, is necessary to prevent nosocomial transmission.

Anti-Bacterial Agents↗
PubMed1992

Identification of a feline immunodeficiency virus gene which is essential for cell-free virus infectivity.

Feline immunodeficiency virus (FIV) contains at least three small open reading frames (ORFs) in the genome, in addition to the three structural genes. Two of these ORFs (putative vif and ORF-A) have unknown functions. Northern (RNA) blot analysis of mRNAs from an FIV-infected cell line showed that the putative-vif-specific mRNA was expressed as a 5.2-kb species. To examine the function of the putative vif gene, we constructed mutants carrying a deletion in either the vif-like gene or the rev gene from an infectious molecular clone of FIV. Although the vif mutant produced virion-associated reverse transcriptase at a normal level upon transfection, cell-free virus prepared from the transfected cells could not infect feline CD4+ cells. The infectivity of the vif mutant, however, was demonstrated in a coculture of the transfected cells and feline CD4+ cells. We conclude that FIV contains the vif gene, which is structurally and functionally similar to that of the primate lentiviruses.

Base Sequence↗