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Biomedical subjects

J Wu

Publications and source records attributed to J Wu.

At least 1,081 records · Page 60Linked to original sources
PubMed1996

Protective effect of S-adenosyl-L-methionine on bromobenzene- and D-galactosamine-induced toxicity to isolated rat hepatocytes.

The protective effect of S-adenosyl-L-methionine (SAMe) on bromobenzene (BB)- or D-galactosamine (GalN)-induced damage to isolated rat hepatocytes and its effect on cellular glutathione (GSH) levels were investigated. SAMe at concentrations of 0.5 to 3.0 mmol/L significantly reduced lactate dehydrogenase leakage from cells exposed to 1.6 mmol/L BB (P < .05 to .001) during 2 hours' incubation. GalN at 25 to 50 mmol/L induced a marked increase of LDH leakage from the cells during the later stage of 24 hours' incubation and SAMe at 1.0 mmol/L clearly attenuated the LDH leakage in GalN (25 mmol/L)-exposed cells. The GSH content in the cells exposed to 2.4 mmol/L BB for 150 minutes was markedly decreased, and further decreased during 24 hours' incubation. SAMe (1.5 mmol/L) both reduced LDH leakage and corrected GSH depletion in cells exposed to 2.4 mmol/L BB. The GSH content in 25 and 50 mmol/L GalN-exposed cells was strikingly diminished to 51.2% and 32.8% of the controls, respectively, during 24 hours' of exposure. SAMe at 1.5 mmol/L significantly reduced the loss in GSH content in 25 mmol/L GalN-exposed cells. The findings show that SAMe has beneficial effects on both BB- and GalN-induced toxicity to rat hepatocytes. The main mechanism behind the protective effect of SAMe on BB and GalN toxicity seems to be associated with enhancement of GSH synthesis in the cells.

Animals↗
PubMed1996

Strategies for Unambiguous Detection of Allelic Heterozygosity via Direct DNA Sequencing of PCR Products: Application to the HLA DRB1 Locus.

Background: Many genetic loci exhibit substantial heterogeneity: the human leukocyte antigen (HLA) DRB loci include 139 alleles and the cystic fibrosis transmembrane regulator gene more than 500 known mutations. Identification of alleles at these loci is cumbersome with typical molecular diagnostic methods such as hybridization assays or restriction enzyme analysis. Direct DNA sequencing of polymerase chain reaction (PCR) products is a general approach to complex loci that allows detection of any allele within the nucleotide sequence analyzed. However, direct DNA sequence-based unambiguous identification of heterozygous nucleotide positions using PCR templates is a challenging problem. Methods and Results: The ability of direct DNA sequencing methods to accurately identify HLA DRB alleles was assessed. The authors evaluated the performance of modified T7 and Taq DNA polymerases in isothermal and thermal cycle sequencing of PCR products derived from HLA DRB genes in 235 individuals who were potential donors or recipients of bone marrow transplants. The uniformity of peak intensity and ability to identify heterozygous nucleotide positions was similar when either AmpliTaq FS- or Sequenase DNA polymerase-derived electropherograms were prepared. The modified Taq DNA polymerase allowed the use of unpurified, double-stranded PCR templates. Furthermore, this enzyme could be used in less laborious, less costly cycle sequencing assays coupled with automated fluorescent detection methodology. Direct sequencing performed with either enzyme allowed unambiguous identification of DRB1 alleles, resolution of difficult heterozygous combinations, and recognition of new alleles. Conclusions: The direct DNA sequencing methods employed here for HLA allele identification are relatively efficient and semiautomated, and may be reasonably considered as a general approach to other complex molecular diagnostic problems, especially when coupled to simplified sequencing chemistries allowing cycle sequencing.

Journal Article↗
PubMed1996

Amniotic fluid index and perinatal morbidity.

Our purpose was: (1) to determine whether assessment of amniotic fluid index in high risk patients with a reactive nonstress test (NST) allowed improved recognition of the fetus at risk for perinatal morbidity than a reactive NST alone; and (2) to determine the optimal low amniotic fluid index (AFI) which should prompt clinical concern. The last NST performed within a week of delivery and amniotic fluid index were retro-spectively compared with various indices of perinatal morbidity. In fetuses with a reactive NST, decreasing AFI was directly correlated with a risk of 5-minute Apgar score of less than 7 and delivery for fetal distress. When various subgroupings of AFI were compared, 7 cm or greater appeared to have a better inverse correlation with the indices of morbidity than lower cut-off values. The addition of AFI assessment to the standard NST allows better prediction of perinatal morbidity than the NSTs alone. Seven centimeters appears to be a reasonable cut-off for clinical concern.

Amniotic Fluid↗
PubMed1996

Determination of heterocyclic amines in flame-grilled fish patty by capillary electrophoresis.

A simple and reliable capillary zone electrophoretic (CZE) method for quantifying mutagenic and carcinogenic heterocyclic amines (HCAs) in cooked foods with UV-visible diode-array detection is described. The buffer system consisted of 50 mM disodium hydrogen phosphate, 30 mM sodium chloride, 20 mM citric acid and 26% methanol at pH 2.1. An uncoated silica tubing, 51 cm in length, was used for the CZE separation. The capillary tubing temperature was maintained at 25 degrees C with a constant voltage of 20 kV. The reproducibility of the method was over 95% for a five-replicate analysis of 10 micrograms/l-spiked 2-amino-3,4,7,8-tetramethylimidazo[4,5-f]quinoxaline (4,7,8-TriMeIQx) and the detection limit was in the low microgram/l range with coefficients of variation between 6 and 18%. An analytical run took only 15 min for 12 known HCAs. Using this procedure, up to 30 samples could be analysed in a single day. The method is reliable and can be used for screening of various HCAs. It has been applied to assess the concentrations of heterocyclic amines in otak-otak, a Malay-style grilled fish patty. The major mutagenic contaminant found in this foodstuff was 2-aminodipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2) (286-1068 micrograms/kg), followed by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) (1.6-13.0 micrograms/kg) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) (14.0-87.5 micrograms/kg). Two co-mutagens norharman (NH) and harman (H) were also detected in otak-otak at levels of 2.0-13.0 micrograms/kg and 12.8-21.3 micrograms/kg, respectively. The substantial amount of Glu-P-2 detected in otak-otak is probably a result of the ingredients used and the high temperature grilling process.

Amines↗
PubMed1996

Differential effects of ketamine and pentobarbitone on acetylcholine release from the rat hippocampus and striatum.

Using microdialysis, we examined the effects of ketamine and pentobarbitone on acetylcholine (ACh) release from the rat hippocampus and striatum. Ketamine 25 and 50 mg kg-1 increased ACh release from the hippocampus to 295% and 353% of basal release, respectively, but not from the striatum. SCH 23390 1 mumol litre-1, a D1 antagonist, significantly inhibited the facilitatory effect of ketamine 50 mg kg-1 on hippocampal ACh release (to 241% of basal level). In contrast, pentobarbitone 20 and 40 mumg kg-1 decreased basal ACh release from both the hippocampus by 41% and 69%, respectively, and the striatum by 37% and 58%, respectively. The results suggest that ketamine and pentobarbitone exert opposite effects on ACh release from the rat hippocampus and that the stimulating effect of ketamine may involve dopamine D1 receptors.

Acetylcholine↗
PubMed1996

Orthogonal array design for optimizing the capillary zone electrophoretic analysis of heterocyclic amines.

Orthogonal array design (OAD) has been applied to the optimization of the capillary zone electrophoretic (CZE) analysis of heterocyclic amines (HCAs), carcinogenic and mutagenic compounds that are found in cooked foods. The factors affecting separation efficiency, such as the pH of the buffer solution, organic modifier and buffer concentrations, the applied potential, and the operating temperature, are studied in two steps under OAD. In the first experiment, each variable is tested at two levels using an OA16 (2(15)) matrix to determine the most important factors and the interactions between them. Based on the results of the first step, the second experiment is implemented according to a three-level OAD with an OA9 (3(4)) matrix, in which more exact values for the important variables are chosen. Finally, the determined optimum conditions for the CZE analysis of the 12 HCAs are applied and evaluated.

Electrophoresis, Capillary↗
PubMed1996

Cancer mortality among silicotics in China's metallurgical industry.

BACKGROUND: We conducted a retrospective cohort study of lung cancer among silicotics in China's metallurgical industries. The study cohort consisted of 4372 male silicotics diagnosed and alive before 1 January 1980. The follow-up period was 1 January 1980 to 31 December 1989. RESULTS: Standardized mortality ratios (SMR) of all deaths, all cancers, chronic bronchopneumonia, pneumonia and pulmonary heart disease, and pulmonary tuberculosis showed statistically significant excesses. The SMR for lung cancer for the total cohort was 237 (P < 0.01). When the total study cohort was divided into various categories by occupation (including iron ore mining, ore-sintering, refractory brick manufacturing, iron and steel smelting, and steel casting), significant excess lung cancer risk was observed among silicotics in all categories (SMR > 200, P < 0.01) except for casting (SMR = 157, P > 0.05). Excess lung cancer was not related to years since diagnosis of silicosis or years of exposure to silica. There was more than twofold excess lung cancer risk among both smoking (SMR = 257, P < 0.01) and non-smoking silicotics (SMR = 209, P < 0.01). Silicosis increased the risk of lung cancer.

China↗
PubMed1996

Language in dreaming and regional EEG alpha power.

In an intensive single-subject design, electroencephalographic (EEG) alpha power and receptive and expressive language in dreaming were studied in 12 dreams during rapid eye movement (REM) sleep on 12 separate nights. Bilateral EEG was recorded continuously from 21 sites and digitized. We used the Fast Fourier transformation (FFT) for power spectral analysis to measure EEG power in the alpha frequency range (8-12 Hz) at each of the EEG sites. The subject was awakened after about 14 minutes into the second REM period, and dream reports were collected. We scored the dream reports for expressive and receptive language. The lower the alpha power on the left sides of those homologous pairs that roughly correspond to Broca's (C3) or Wernicke's area (P3), the more expressive or receptive language in dream reports. The largest difference between the correlation of the left and that of the right homologous pair of regions was found in the central (C3, C4) area for expressive language and in the parietal (P3, P4) area for receptive language. Our finding suggests lateralized and localized cortical activation in relation to language in dreaming.

Adult↗
PubMed1996

Murine cells transfected with human Hsp27 cDNA resist TNF-induced cytotoxicity.

Hyperthermia sensitizes tumor cells to killing by tumor necrosis factor-alpha (TNF). Sensitization is greater in cells exposed to TNF before heating begins than with the reverse sequence, and heat-shock proteins (hsp) have been suggested to protect cells from TNF cytotoxicity. Here we examined the role of Hsp27 in TNF resistance. Murine L929 cells were stably transfected with the vector pRc/CMV constitutively to express an inserted human hsp27 complementary DNA (cDNA) sequence. Parental cells produced no detectable murine homolog to human hsp27. Hsp27-sense clones expressed hsp27 messenger RNA (mRNA) and protein at 37 degrees C. Cells transfected with the cDNA in the anti-sense orientation produced anti-sense mRNA but no protein, and cells transfected with the vector alone produced neither product. Expression of hsp27 conferred significant resistance to TNF cytotoxicity in both neutral red cytotoxicity and clonogenic survival assays. Vector along and hsp27 anti-sense transfectants had a TNF response similar to that of parental L929 cells. Kinetic studies in L929 cells showed that hsp27-expressing clones exhibited resistance relative to parental cells beginning 6 h after TNF exposure, and this differential response increased by 12 and 24 h. Addition of actinomycin D to the TNF cytotoxicity assays accelerated the cytotoxicity development in parental and transfected cells, but the hsp27-sense clones were still more resistant. Hsp27-sense clones of L929 cells were also resistant to oxidative stress induced by menadione and released less arachidonic acid in response to TNF induction. These results show that hsp27 can negatively regulate the TNF cytotoxic mechanism.

Animals↗
PubMed1996

Surgical correction of submucous cleft palate with Furlow palatoplasty.

Many surgeons have favored using the pharyngeal flap as the primary treatment for the velopharyngeal insufficiency associated with submucous cleft palate. However, the increasing number of reports of sleep apnea and airway compromise as a result pharyngeal flap surgery support the need to eliminate any unnecessary pharyngeal flap surgery. From 1988 to 1993, 35 Chinese submucous cleft palate patients with velopharyngeal insufficiency received surgery. A Furlow palatoplasty was used in 30 patients (3 to 26 years old). The follow-up duration was 9 months to 5 1/2 years. These patients were selected after a thorough study for velopharyngeal insufficiency including intraoral examination, perceptual speech assessment, videonasopharyngoscopy, and/or multiview videofluoroscopy. The criteria for selection included age, intraoral finding of an obviously anterior inserted levator palatine muscle, size of velopharyngeal gap, pattern of velopharyngeal closure, degree of lateral pharyngeal wall movement, and response to biofeedback speech therapy. In general, younger patients with circular or sagittal pattern closure, a velopharyngeal gap less than 5 mm, or good response to biofeedback speech therapy were considered to be the best candidates for a Furlow palatoplasty. The 5 patients who did not fulfill these criteria and whose velopharyngeal function failed to improve on preoperative biofeedback therapy were treated by pharyngeal flap operation. Twenty-nine patients (96.7 percent) achieved competent velopharyngeal function after the Furlow palatoplasty. The procedure corrected the velopharyngeal insufficiency in 3 patients older than 20 years with a velopharyngeal gap of less than 2 mm. The only patient with an unsatisfactory result was a 26-year old woman who had very prominent action of the musculus uvulae before the surgery. The results show that a Furlow palatoplasty can satisfactorily correct velopharyngeal insufficiency in carefully selected submucous cleft palate patients and thus avoid the serious complications of pharyngeal flap surgery.

Adolescent↗
PubMed1996

Morphological model of human colon tissue fluorescence.

Fluorescence spectroscopy of tissue is a promising technique for early detection of precancerous changes in the human body. Investigation of the microscopic origin of the clinically observed tissue fluorescence can provide valuable information about the tissue's histology. The objective of this study was the development of a morphological model of colon tissue fluorescence which connects the clinically observed spectra with their underlying microscopic origins. Clinical colon tissue fluorescence which connects the clinically observed spectra with their underlying microscopic origins. Clinical colon tissue fluorescence spectra were modeled by measuring the intrinsic fluorescence properties of colon tissue on a microscopic level and by simulating light propagation in tissue using the Monte-Carlo method. The computed spectra were in good agreement with the clinical spectra acquired during colonoscopy, and exhibited the characteristic spectral features of the in vivo collected spectra. Our analysis quantitated these spectral features in terms of the intrinsic fluorescence properties of tissue and its general histological characteristics. The fluorescence intensity difference between normal and adenoma observed in vivo was found to be due to the increased hemoglobin absorption, the reduced mucosal fluorescence intensity, and the absence of submucosal fluorescence in adenomatous polyps. The increased red fluorescence in adenoma was found to be associated with the dysplastic crypt cell fluorescence.

Absorption↗
PubMed1996

Strategy for distinguishing a new DQB1 allele (DQB1*0611) from the closely related DQB1*0602 allele via sequence specific PCR or direct DNA sequencing.

A novel DQ6 allele (DQB1*0611) was identified via direct DNA sequencing in an African-American donor for bone marrow transplantation. The allele was not suspected on the basis of a sequence specific PCR assay which instead indicated the presence of DQB1*0602. DQB1*0602 and DQB1*0611 differ in exon 2 only at codon 9 resulting in a tyrosine substitution for phenylalanine. A modification of current DQB1 sequence specific PCR assays was devised which allows distinction between the closely related DQB1*0602 and DQB1*0611 alleles. Preliminary allele frequency studies suggest that DQB1*0611 is rare both in a non-African American sample and in American of African descent carrying DR11, DQ6 haplotypes. The selection of various DQB1*0611 detection methods is discussed.

Alleles↗
PubMed1996

Potentiation by sevoflurane of the gamma-aminobutyric acid-induced chloride current in acutely dissociated CA1 pyramidal neurones from rat hippocampus.

1. The effects of a new kind of volatile anaesthetic, sevoflurane (Sev), on gamma-aminobutyric acid (GABA)-gated chloride current (Icl) in single neurones dissociated from the rat hippocampal CA1 area were examined using the nystatin perforated patch recording configuration under the voltage-clamp condition. All drugs were applied with a rapid perfusion system, termed the "Y-tube' method. 2. When the concentrations were higher than 3 x 10(-4) M, Sev, itself, induced an inward current (ISev) at a holding potential (VH) of -40 mV. The concentration-response curve of ISev was bell-shaped, with a suppressed peak and plateau currents at high concentrations (above 2 x 10(-3) M). The reversal potential of ISev (ESev) was close to the theoretical Cl- equilibrium potential, indicating that ISev was carried mainly by Cl-. 3. ISev was reversibly blocked by bicuculline (Bic), an antagonist of the GABAA receptor, in a concentration-dependent manner with a half-inhibitory concentration (IC50) of 7.2 x 10(-7) M. But ISev was insensitive to strychnine (Str), an antagonist of the glycine receptor. 4. At low concentrations (between 3 x 10(-4) and 10(-3) M), Sev markedly enhanced the 10(-6) M GABA induced current (IGABA) but reduced the IGABA with accelerating desensitization accompanied by a "hump' current after washout at high concentrations (higher than 2 x 10(-3) M). 5. Sev, 10(-3) M potentiated the current induced by low concentrations of GABA (between 10(-7) and 3 x 10(-6) M) but reduced the current induced by high concentrations (higher than 10(-5) M) of GABA with a clear acceleration of IGABA desensitization. 6. Sev, like pentobarbitone (PB), pregnanolone (PGN) or diazepam (DZP), potentiated the 10(-6) M GABA-induced response without shifting the reversal potential of IGABA. 7. ISev was augmented by PB, PGN, or DZP at concentrations that maximally potentiated IGABA, suggesting that Sev enhanced IGABA at a binding site distinct from that for PB, PGN, or DZP. 8. It is concluded that Sev acts on the GABAA receptor complex mimicking the GABA-induced chloride current at high concentrations. At low concentrations, Sev enhances GABA-gated chloride current at a binding site independent of the allosteric modulator sites of barbiturates, benzodiazepines or neurosteroids. The reversible potentiation of the inhibitory GABAA receptor-mediated Cl- current may result in the depressing of postsynaptic excitability and may, at least in part, underlie the anaesthetic action of Sev.

Animals↗
PubMed1996

Preponderance of Fis-binding sites in the R6K gamma origin and the curious effect of the penicillin resistance marker on replication of this origin in the absence of Fis.

Fis protein is shown here to bind to 10 sites in the gamma origin of plasmid R6K. The Fis-binding sites overlap all the previously identified binding sites in the gamma origin for the plasmid-encoded pi initiator protein and three host-encoded proteins, DnaA, integration host factor, and RNA polymerase. However, the requirement of Fis for R6K replication depends on the use of copy-up pi-protein variants and, oddly, the antibiotic resistance marker on the plasmid. In Fis-deficient cells, copy-up pi variants cannot drive replication of R6K gamma-origin plasmids carrying the bla gene encoding resistance to penicillin (Penr) but can drive replication of plasmids with the same origin but carrying the chloramphenicol acetyltransferase gene encoding chloramphenicol resistance (Cmr). In contrast, R6K replication driven by wild-type pi is unaffected by the antibiotic resistance marker in the absence of Fis protein. Individually, none of these elements (copy-up pi, Fis deficiency, or drug markers) prevents R6K replication. The replication defect is not caused by penicillin in the medium or runaway replication and is unaffected by the orientation of the bla gene relative to the origin. Replication remains inhibited when part of the bla coding segment is deleted but the bla promoter is left intact. However, replication is restored by insertion of transcriptional terminators on either side of the gamma origin, suggesting that excess transcription from the bla gene may inactivate replication driven by pi copy-up mutants in the absence of Fis. This study suggests that vector sequences such as drug markers may not be inconsequential in replication studies, as is generally assumed.

Bacterial Proteins↗
PubMed1996

Effects of nutrition and growth rate on Lrp levels in Escherichia coli.

Lrp (leucine-responsive regulatory protein) activates some Escherichia coli operons that function in anabolism and represses others involved in catabolism (for a review, see J. M. Calvo and R. G. Matthews, Microbiol. Rev. 58:466-490, 1994). This overall pattern suggests that Lrp may help cells adapt to changes in the nutritional environment. Here, we tested the idea that the nutritional richness of the medium determines the amount of Lrp in cells. Lrp was measured directly by Western blotting (immunoblotting) in cells grown in a chemically defined rich medium or in a minimal medium. In addition, transcription from the lrp promoter was assessed with a lacZ reporter gene. The results with these two different measurements were nearly the same, indicating that under the conditions employed, beta-galactosidase measurements can accurately reflect Lrp levels. For cells in a minimal medium, Lrp levels were consistently lowest during the logarithmic phase of growth, but overall, there was not much variation in levels as a function of growth phase (1.3-fold difference between highest and lowest values). However, for cells in a rich medium, Lrp levels dropped 3- to 4-fold during the lag phase, remained constant during the log phase, and then rose to starting levels upon entry into the stationary phase. When cells in the log phase were compared, Lrp levels were 3- to 4-fold higher in cells growing in a minimal medium than those in a rich medium. The levels of lrp expression were the same or slightly higher in strains containing mutations in rpoS, cya, or crp compared with wild-type strains, suggesting that neither RpoS nor the cyclic AMP (cAMP) receptor protein-cAMP complex is required for expression. On the other hand, lrp expression was severely restricted in cells that could not make ppGpp because of mutations in relA and spoT. The reduced expression of lrp during logarithmic growth in a rich medium may be due to low ppGpp levels under these conditions. The repressive effects of rich medium and the stimulatory effects of ppGpp were also observed with a construct having only a minimal lrp promoter (-57 to +21). The results of other experiments suggest that Lrp levels vary inversely with the growth rate of cells instead of being determined by some component of the medium.

Adenylyl Cyclases↗
PubMed1996

Isolation, identification, and transcriptional specificity of the heat shock sigma factor sigma32 from Caulobacter crescentus.

We report the identification of the Caulobacter crescentus heat shock factor sigma32 as a 34-kDa protein that copurifies with the RNA polymerase holoenzyme. The N-terminal amino acid sequence of this protein was determined and used to design a degenerate oligonucleotide as a probe to identify the corresponding gene, rpoH, which encodes a predicted protein with a molecular mass of 33,659 Da. The amino acid sequence of this protein is similar to those of known bacterial heat shock sigma factors of Escherichia coli (41% identity), Pseudomonas aeruginosa (40% identity), and Citrobacter freundii (38% identity). The isolated C. crescentus gene complements the growth defect of an E. coli rpoH deletion strain at 37 degrees C, and Western blot (immunoblot) analysis confirmed that the gene product is related to the E. coli sigma32 protein. The purified RpoH protein in the presence of RNA polymerase core enzyme specifically recognizes the heat shock-regulated promoter P1 of the C. crescentus dnaK gene, and base pair substitutions in either the -10 or -35 region of this promoter abolish transcription. S1 nuclease mapping indicates that rpoH transcripts originate from two promoters, P1 and P2, under the normal growth conditions. The P2 promoter is similar to the sigma32 promoter consensus, and the P2-specific transcript increases dramatically during heat shock, while the P1-specific transcript remains relatively constant. These results suggest that although the structure and function of C. crescentus sigma32 appear to be very similar to those of its E. coli counterpart, the C. crescentus rpoH gene contains a novel promoter structure and may be positively autoregulated in response to environmental stress.

Amino Acid Sequence↗
PubMed1996

Charged amino acid residues of human immunodeficiency virus type 1 nucleocapsid p7 protein involved in RNA packaging and infectivity.

Interaction of the human immunodeficiency virus type 1 (HIV-1) Gag precursor polyprotein (Pr55Gag) with the viral genomic RNA is required for retroviral replication. Mutations that reduce RNA packaging efficiency have been localized to the highly basic nucleocapsid (NC) p7 domain of Pr55Gag, but the importance of the basic amino acid residues in specific viral RNA encapsidation and infectivity has not been thoroughly investigated in vivo. We have systematically substituted the positively charged residues of the NC domain of Pr55Gag in an HIV-1 viral clone by using alanine scanning mutagenesis and have assayed the effects of these mutations on virus replication, particle formation, and RNA packaging in vivo. Analysis of viral clones with single substitutions revealed that certain charged amino acid residues are more critical for RNA packaging efficiency and infectivity than others. Analysis of viral clones with multiple substitutions indicates that the presence of positive charge in each of three independent domains--the zinc-binding domains, the basic region that links them, and the residues that Hank the two zinc-binding domains--is necessary for efficient HIV-1 RNA packaging. Finally, we note that some mutations affect virus replication more drastically than RNA incorporation, providing in vivo evidence for the hypothesis that NC p7 may be involved in aspects of the HIV life cycle in addition to RNA packaging.

Base Sequence↗