[Treatment of chronic aplastic anemia with triolandren and cyclosporin A]

OBJECTIVE

To explore more effective regimen for chronic aplastic anemia (CAA).

METHODS

Forty-five cases of CAA were treated with triolandren (TLD) (15 cases) or TLD and cyclosporin A (CsA) (30 cases).

RESULTS

The response rate of TLD-CsA group (83.3%) was higher than that of TLD group (60.0%), furthermore, the recovery of bone marrow colony-forming cell (CFC) number of the responding patients was more complete and rapid in TLD-CsA group than in TLD group. Bone marrow CFC number had no significant change of all nonresponding patients in both groups.

CONCLUSION

The response rate of TLD-CsA was higher than that of TLD alone, and the recovery of bone marrow CFC number of the responding patients was more complete and rapid in TLD-CsA group.

[Serum level of granulocyte colony stimulating factor in severe aplastic anemia patients]

OBJECTIVE

To investigate the relationship between serum level of granulocyte colony stimulating factor (G-CSF) and clinical status, treatment outcome and prognosis in severe aplastic anemia (SAA-I) patients.

METHODS

Serum G-CSF level was detected by ELISA assay in 36 SAA-I patients.

RESULTS

Pre-treatment serum G-CSF levels of 27/36 (75%) SAA-I patients were above normal. These patients achieved better curative outcomes in a shorter period of treatment.

CONCLUSION

Detection of serum G-CSF level in SAA-I patients is helpful for judging the clinical status and prognosis.

Point mutations of muscle mitochondrial DNA from patients with mitochondrial encephalomyopathies

OBJECTIVE

To study the relation between point mutations at nt3243 and nt8344 of muscle mitochondrial DNA from patients with mitochondrial encephalomyopathies and phenotypes.

METHODS

DNA was extracted from muscle specimens from 5 patients with mitochondrial encephalomyopathies and and amplified by PCR method, using corresponding oligonucleotide primers. DNA fragments were digested with restriction enzymes Bgl I and Apa I, then the digested DNA fragments were analyzed with an electrophoresis method.

RESULTS

The point mutation at nt3243 of mtDNA was found in 2 patients, one with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) and another with myoclonic epilepsy with ragged red fibers (MERRF). The point mutation at nt8344 was found in 2 patients with MERRF, including the one with point mutation at nt3243.

CONCLUSION

The point mutation of DNA at nt3243 correlated with MELAS and nt8344 correlated with MERRF. In addition, the detection of point mutations at both nt3243 and nt8344 in a patient with MERRF shows the association of mutation with diversity in clinical manifestations of mitochondrial encephalomyopathies.

[A study on the effect of house dust mite on interleukin-10 secretion of peripheral blood lymphocytes in patients with allergic asthma]

OBJECTIVE

To investigate the relationship between interleukin (IL)-10 and allergic asthma, and the effect of antigen on IL-10.

METHODS

The supernatant of cultured peripheral blood lymphocytes (PBLC) from 20 patients with allergic asthma and 20 normal subjects with different stimuli [home-dust-mite (HDM) or dexamethasone] was determined for IL-10, by means f enzyme-linked immunosorbent assay.

RESULTS

(1) IL-10 was significantly decreased in asthma group, as compared with the control group (P < 0.01); (2) Less IL-10 was released in HDM-stimulated PBLC in asthma (P < 0.01); (3) IL-10 was obviously increased in dexamethason-stimulated whether in the asthma or in the control group.

CONCLUSION

The diminished IL-10 production from PBLC could be related to asthmatic attack in patients with allergic asthma. Dexamethason might exert, at least, a part of anti-inflammatory activity by inducing IL-10 secretion of PBLC.

[Detecting mycobacteria and their L-forms in peripheral blood from pulmonary tuberculosis patients by cultivation with hemolyzed-centrifugated blood in liquid medium]

OBJECTIVE

To establish a new method of detecting mycobacteria and their L-forms in blood.

METHODS

65 samples of peripheral blood from patients with pulmonary tuberculosis were cultivated directly or cultivated with hemolyzed-centrifugated blood sediments in 92-3TB and 92-3TBL liquid medium, and the cultures were staining with immunoenzyme technique (ABC method).

RESULTS

In 65 specimens, the positive rates of mycobacteria and their L-forms were 15%, 26% respectively with total isolation rate of 32%. In cultivating with hemolyzed-centrifugated blood the positive rate was much higher than direct cultural method (P < 0.05). In sputum the positive rates of acid-fast bacilli and their L-forms were 38% and 20% respectively, with total isolation rate of 52%, higher than that in peripheral blood (P < 0.05), and the total positive rate of combinative detection of blood and sputum salmples was 65%.

CONCLUSIONS

Mycobacteria and their L-forms exist in peripheral blood of patients with pulmonary tuberculosis, and mainly in L-forms. Cultivation with hemolyzed-centrifugated blood in liquid medium and staining with immunoenzyme technique are valuable in routine detection of mycobacteria and their L-forms in peripheral blood. The positive rate of bacterial culture of pulmonary tuberculosis could be increased in combination with sputum mycobacteria and their L-forms examination.

[Evaluation of preventive studies of Chinese Journal of Tuberculosis and Respiratory Diseases 1978-1997]

OBJECTIVE

To investigate the current situation of clinical trial about preventive research paper on respiratory diseases in China. To stress the design of the research, and to improve the quality of the studies.

METHODS

All the preventive and treatment studies of Chinese Journal of Tuberculosis and Respiratory Diseases (1978-1997) were assessed according to evidence based medicine (EBM) standard.

RESULTS

In the past 20 years, 394 preventive study papers were published, 41 were random control trial (RCT), 50 were clinical control trial (CCT), the total percentage of RCT and CCT was 23.1%, and quality problem also existed.

CONCLUSIONS

The design of the study in the respiratory diseases is not rigorous, thus the accuracy of the result is greatly affected. Improving the design of the research and the statistics method is very important to improve the quality of the research.

A preliminary investigation of Tanakan in the treatment of hypertensive arteriosclerosis and stroke in rats

OBJECTIVE

To observe the changes in hypertensive cerebral arteriosclerosis and the incidence of stroke in rats following treatment with Tanakan, a preparation of Ginkgo Biloba (GB).

METHODS

Using two-kidney, two clip renovascular hypertensive rats (RHRs) as animal models--we investigated changes in these hypertensive arteriosclerosis-associated factors: A I, A II, ALD, ET, SOD and cGMP. Blood levels were observed after oral administration of GB, at both early and late stages of hypertension.

RESULTS

The degree of arteriosclerosis was more severe in both RHRs control and the later treated group than in the early treated group, with blood levels of A I, A II, ALD and ET in the former two groups significantly elevated. The degree of arteriosclerosis in the early treated group decreased and the blood levels of A I, A II, ALD and ET in this group decreased nearly to normal levels. The blood levels of SOD and cGMP were also elevated in the early treated group.

CONCLUSIONS

These results reveal that it is important to treat hypertension as soon as possible, in order to reduce the occurrence of stroke.

[Transarterial chemoembolization with high dose iodized oil for the treatment of large hepatocellular carcinoma]

OBJECTIVE

To report the method and result of high dose iodized oil chemoembolization for the treatment of large hepatocellular carcinoma.

METHODS

From 1993 to 1998, 163 patients with unresectable hepatocellular carcinoma were treated by transarterial chemoembolization (TACE) with more than 20 ml lipiodol.

RESULTS

TACE with high dose lipiodol was well tolerated by the treated patients. In patients whose liver function was of Child A stage, or in patients whose residual indocyanine green level 15 min after injection was less than 20%, the frequency of post-treatment hepatic insufficiency was not significantly different from that of patients treated with routine dose of lipiodol. On CT scan at 4 wk after TACE, more lipiodol was located in the liver. The 1-, 2-,3-year survival rate of patients in Child A stage was 79.8%, 50.3%, and 38.5%, respectively, as compared to 57.5%, 24.8% and 8.37%, respectively in patients treated with routine dose of lipiodol (P = 0.0136).

CONCLUSION

High dose lipiodol TACE for the treatment of large hepatocellular carcinoma is practically acceptable with better therapeutic effect but its use should be limited to those patients with compensated liver function.

[Study on the in vitro and in vivo thrombolytic efficacy of bispecific antifibrin-antiurokinase monoclonal antibodies]

OBJECTIVE

To evaluate the thrombolytic efficacy of bispecfic antifibrin-antiurokinase monoclonal antibodies.

METHODS

Murine hybrid hybridomas secreting bispecific monoclonal antibodies (bsMcAbs) were prepared by fusing a mutant hybridomas secreting antifibrin McAbs with spleen cells of murine immunized with urokinase. The binding power of bsMcAbs with fibrin or urokinase was determined by ELISA method. The in vitro thrombolytic efficacy was measured by the dissolving rate of 131I-plasma clot. The in vivo thrombolytic efficacy was measured by using the rabbit jugular vein thrombus model.

RESULTS

8 strains of bsMcAbs have been obtained. ELISA experiments showed that bsMcAbs have very strong binding power with fibrin or urokinase. The bsMcAbs bound with urokinase increased the in vitro thrombolytic efficacy of urokinase by 15.5%. The in vivo thrombolytic efficacy of bsMcAbs bound with urokinase was 1.6-2.1 times as high as urokinase.

CONCLUSIONS

Monoclonal antibody-directed thrombolytic agents have advantages of high specificity and strong local thrombolytic efficacy. It is well worth going on further study.

[Effect of a new triclosan-containing mouth rinse on oral infection]

OBJECTIVE

To study the effect of a new Triclosan-containing mouthrinse--LIBO Anti-plaque mouth rinse on oral infection.

METHODS

1. Before and after the use of triclosan mouthrinse: the gingival data were checked and secorded; plaque sausples were collected, cultured in selective and non-selective media, bacteria were isolated, sounted, and compased. 2. With Streptococcus mutans and P. Gingivalis as experimental bacteria, triclosan and chlorhexidine (CHX) mouthrinses anti-bacterium substance, the minimum inhibitory concentrations (MICs) of the two rinses were compared. 3. Smooth plates with the film of Streptococcus mutans C were set in different mouthrinses and water. Observing the exfoliation of bacteria film from the plates in three agents.

RESULTS

1. Triclosan mouthrinse was effective to decrease the plaque index (PLI) and supragingival bleeding index (SBI). 2. The bacteria count obtained after use of triclosan mouthrinse was lower than that before using it. 3. The minimum inhibitory concentrations of triclosan mouthrinse against Streptococcus mutans C was much lower than that of chlorhexidine mouthrinse. 4. In triclosan mouthrinse, the bacterial films were most easily exfoliated from the plate. Triclosan mouthrinse has strongest anti-adhesion effect among the three tested agents.

CONCLUSIONS

Triclosan mouthrinse has continuous disinfecting effect and help control the formation and adhesion of dental plaque.

[Mitochondrial DNA sequence evolution and phylogenetic relationships of gibbons]

The phylogenetic relationships of gibbons are still open questions. We have sequenced a mitochondrial cytochrome b gene fragment from Hylobates hoolock, H. concolor, H. lar and H. syndactylus. Combined with the sequences from Garza and Woodruff (1992), we have constructed a comprehensive phylogenetic tree of the gibbons using the maximum-parsimony analysis. Our results suggested that the gibbons should be divided into four groups: (1) hoolock, (2) syndactylus, (3) agilis, lar, muelleri and klossi, and (4) concolor, which correspond to the four morphological subgenera. There are at least four distinct clades in the concolor population, which indicates that the concolor may be divided into at least four species. Therefore, those four clades should be managed separately with the same conservation effort.

Improved ultrastructural preservation of bioprosthetic tissue

BACKGROUND AND AIMS OF THE STUDY

Poor ultrastructural tissue preservation of bioprosthetic heart valves is associated with a higher propensity for calcification. In spite of this realization, commercial valve fixation remains suboptimal.

METHODS

In an attempt to maintain tissue integrity through improved cross-linking procedures, transmission electron microscopy and a 21-point damage score were applied to assess the ultrastructural preservation of aortic wall tissue-the main component of contemporary aortic valve bioprostheses. An ideal glutaraldehyde (GA) concentration was assessed by immediate tissue fixation at 4 degrees C comparing 0.2%, 0.5%, 0.65%, 1.0%, 2.0%, 3.0% and 4.0% GA in phosphate-buffered saline (PBS). Subsequently, an optimal concentration of 3.0% GA was used to determine the effect of fixation temperature (4 degrees, 22 degrees and 37 degrees C). Finally, the superior glutaraldehyde concentration (3.0%) and cross-linking temperature (4 degrees C) were used to assess tolerance towards delayed fixation.

RESULTS

When different GA concentrations were used almost identical damage scores of 6.3 and 5.8 were found for 0.2% and 0.65% fixation. The first significant improvement was found at a concentration of 1.0% (score 3.3; p < 0.01) followed by a further improvement at 3.0% (score 2.6; p = 0.05). The optimal fixation temperature was 4 degrees C (3.7) with the worst results obtained at room temperature (score 9.2; p < 0.03). When fixation was delayed, the most significant damage occurred during the initial 30 min after slaughter (from 2.3 to 7.4; p < 0.02) followed by another significant deterioration between 4 and 16 h (from 5.6 to 9.7; p < 0.02).

CONCLUSIONS

In summary, the prerequisites for an ideal ultrastructural preservation of bioprosthetic aortic wall tissue are immediate fixation (within 30 min), high GA concentrations (> 1.0%) and cold-temperature fixation (4 degrees C).

Are risk factors for patellofemoral and tibiofemoral knee osteoarthritis different?

OBJECTIVE

To determine whether patellofemoral (PF), tibiofemoral (TF), and combined patterns of knee osteoarthritis (OA) differ in their strengths of associations with any of the known risk factors for knee OA, and especially to evaluate whether body mass index (BMI) correlates with all 3 patterns, or only with tibiofemoral disease, as previously suggested.

METHODS

We obtained anteroposterior and lateral knee radiographs on 608 participants at the 22nd biennial examination of the Framingham cohort study (1992-3). The presence or absence of OA in the TF and PF compartments of each knee was scored, and subjects were classified on the basis of the pattern of compartmental involvement in their 2 knees. The strength of association of age, sex, BMI, chondrocalcinosis, and knee injury was computed for PF, TF, and combined pattern of knee OA using multiple logistic regression.

RESULTS

The mean age and BMI of the sample were 80.7 yrs (SD 5.0) and 25.4.kg-2 (SD 3.7), respectively. PF, TF, and combined patterns of knee OA were present in 5.3, 23.0 and 19.7%, respectively. Elevated BMI was a risk factor for all 3 patterns of disease (adjusted OR for highest vs lowest tertile of BMI 3.7, 1.9, and 7.0 for PF, TF, and combined pattern, respectively). Risk factor profiles were broadly similar for TF and PF OA, with the possible exception of knee injury in men (adjusted OR = 2.0 for PF, 3.7 for TF OA). Risk factors were generally more strongly associated with the combined pattern of OA.

CONCLUSION

Obesity is an important risk factor for PF, TF, and combined patterns of knee OA. The relationships of these patterns with the risk factors investigated here appear similar and are strongest for the combined pattern.

[Experimental study of proliferation effects of platelet derived wound healing factor on tissue cells of wound]

This experiment was designed to observe the proliferative effects of platelet derived wound healing factor (PDWHF) of different concentrations on fibroblasts from rat wounds and on epithelial from human wounds. Cultured fibroblasts from rat wound and epithelia from human wound were randomly divided into three groups. (1) In blank control, the cells were treated with basic medium (BM, contains 1640/0.5% FCS); (2) the positive control, the cells were treated with 1640/10% FCS and (3) in the PDWHF group, the cells were treated respectively with BM/1% PDWHF, BM/3% PDWHF, BM/5% PDWHF, BM/7% PDWHF, BM/10% PDWHF, BM/12% PDWHF, respectively. The Cells were collected after 48 hours culturing with BM or PDWHF, and the cell proliferation was measured by MTT method according to the OD values. The result showed that the PDWHF could remarkably enhance the proliferation of fibroblasts and epithelial cells when its concentration was between 1% and 7%, which was obviously higher than that of the blank control (P < 0.01). When the concentration of PDWHF reached 10%, its proliferative effect was not remarkable when compared with the blank control, When the concentration of PDWHF reached 12%, it showed inhibitory effect on fibroblasts and manifested no obvious inhibitory effect on epithelial cells. It was concluded that the PDWHF was a combination of a variety of growth factors. In a certain range of concentration, the PDWHF might effectively promote the proliferation of fibroblasts and epithelial cells. Howerve, when its concentration reached to relatively higher level, its effect was not remarkable any more, or even showed inhibitory effect on cell proliferation.

[Treatment of avascular necrosis of talus with vascularized bone graft]

In order to study the curative effect of vascularized bone graft in the treatment of avascular necrosis of talus, 24 patients were treated with vascularized bone grafts, in which 9 cases had received 1st cuneiform bone graft with a malleolaris anteriomedialis, 4 cases with the 1st cuneiform bone graft with the medial tarsal artery and 11 cases with vascularized cuboid bone graft with the lateral tarsal artery. All of the patients were followed up for 3-5.5 years. The clinical observation and X-ray examination showed that function of the ankle joint was completely or almost normal in 16 cases, and the bone repair was excellent. There was slight pain in the ankle joint in 4 cases. The efficiency rate of the treatment was 83.3%. It could be concluded that vascularized bone graft might be an effective method in the treatment of avascular necrosis of talus.

Efflux transport of [3H]GABA across blood-brain barrier after cerebral ischemia-reperfusion in rats

AIM

To study whether the efflux transport of [3H]GABA across the blood-brain barrier (BBB) would be enhanced after cerebral ischemia-reperfusion.

METHODS

Brain efflux index (BEI) of [3H]GABA was determined in ischemic-reperfused rats after [3H]GABA or [3H]GABA combined with unlabeled GABA or probenecid (Pro) was microinjected into the parietal cortex area 2 (Par 2), and brain uptake of Evans blue (EB) was assessed after i.v. EB.

RESULTS

BEI in rats subjected to 10-min ischemia and 30-min, 2-h, 6-h, or 24-h reperfusion were 67%, 83%, 92%, and 87%, respectively, which were higher than that in control (58%). The brain uptake of EB was also considerably increased. Unlabeled GABA or Pro obviously decreased BEI in normal or 6-h reperfused rats, but GABA had no obvious effect on that in 5-min reperfused rats.

CONCLUSION

The efflux transport of [3H]GABA was markedly enhanced after cerebral ischemia-reperfusion in rats.

Promotion of chondrocyte proliferation by versican mediated by G1 domain and EGF-like motifs

We have previously demonstrated that versican stimulated NIH3T3 fibroblast proliferation. Since versican is expressed in cartilage, we investigated whether versican plays a role in chondrocyte proliferation. We developed a technique to stably express a recombinant versican mini-gene in chicken chondrocytes, and its effect on chondrocyte proliferation was analyzed by the increase in cell number. The effect of cell adhesion on cell proliferation was tested. Finally, the versican mini-gene was truncated to assess the role of EGF-like motifs in cell proliferation. Expression of the recombinant versican mini-gene stimulated chondrocyte proliferation. Antisense oligonucleotides complementary to versican inhibited chondrocyte proliferation. The G1 domain of versican stimulated chondrocyte proliferation by destabilizing chondrocyte adhesion. Furthermore, deletion of the two EGF-like motifs from the G3 domain also reduced the function of versican in stimulating cell proliferation. Versican enhances chondrocyte proliferation through a mechanism involving its G1 and G3 domains. This finding may have implications for our understanding of the pathogenesis of various joint diseases.

Effects of sex hormones on action potential and contraction of guinea pig papillary muscle

AIM

To study the effects of sex hormones, estradiol (Est), progesterone (Pro) and testosterone (Tes) on the action potential (AP) and contraction of guinea pig papillary muscle.

METHODS

Using conventional glass microelectrode and mechanical recording of myocardial contraction.

RESULTS

Est slowed down the maximal rate of rise of phase 0 (Vmax) of AP at low concentration (1 mumol.L-1). At 10 mumol.L-1 and above, Est also prolonged AP duration (APD50 and APD90), effective refractory period (ERP) and decreased the maximal isometric tension (Pmax) and velocity of tension development (dT/dt) of contraction. Tes (100 mumol.L-1 - 1 mmol.L-1) prolonged APD90 and ERP with decreased Pmax and dT/dt. But Pro (1 mumol.L-1 - 1 mmol.L-1) had no effects on both AP and contraction.

CONCLUSION

Est prolonged AP and depressed contraction of guinea pig papillary muscle.

Involvement of interleukin-2 in analgesia produced by Coriolus versicolor polysaccharide peptides

AIM

To study the role of interleukin-2 (IL-2) and mediobasal hypothalamus (MBH) in analgesia produced by Coriolus versicolor polysaccharide peptide (PSP).

METHODS

The IL-2 antiserum was injected i.c.v. or i.p. and the MBH was destroyed electrolytically.

RESULTS

PSP i.g. 1 g.kg-1.d-1 for 6 d increased the pain threshold in tail stimulation-vocalization test in rats. This PSP-produced analgesia was blocked by i.c.v., but not i.p., IL-2 antiserum and disappeared after electrolytic lesion of MBH.

CONCLUSION

The analgesia produced by PSP is mediated by IL-2 which is activated by PSP and interacts with IL-2 receptors in the MBH.

Tissue folate binding protein levels in transgenic mice with tumors and in non-transgenic controls

Localized folate deficiency may be a risk factor for cancer. Since, folate binding proteins (FBP) and reduced folate carrier proteins (RFC) mediate cellular transport of folate, we compared FBP concentrations in several organs from tumor-bearing transgenic (TBT) mice and tumor-free non-transgenic controls (NTC) of the same strain, age, and fed identical diets. Liver, spleen, brain, small intestine and kidney were individually homogenized in phosphate-buffered saline (PBS) and separated into membrane, cytoplasmic, mitochondrial/lysomal and nuclear fractions (confirmed with marker enzymes). Homogenates and fractions was analyzed for total protein, and FBP. We used rabbit anti-bovine milk antibody and ELISA to measure FBP. FBP concentrations in kidney, small intestine, and spleen of TBT mice were higher than those of NTC mice; the opposite was true in liver and lung. FBP seemed to be upregulated in kidneys (all fractions), small intestine (all fractions), and spleen (cytoplasmic and nuclear fractions only) of TBT mice compared to NTC mice; the opposite appeared true in liver (all fractions) and lung (all fractions). FBP concentrations in brain, heart, and muscle of TBT mice were not different from those in brain, heart and muscle of NTC mice. A longitudinal study will determine if these changes in FBP concentrations precede tumor onset.

[Genetic complementation group analysis of xeroderma pigmentosum patients in China]

OBJECTIVE

To establish skin fibroblast cell strains derived from Chinese xeroderma pigmentosum(XP) patients and to analyze the genetic complementation group and distribution.

METHODS

From four XP patients, skin fibroblast cell strains were derived and used for the complementation group analysis by autoradiography and cell-fusion technique.

RESULTS

Of the four XP patients from apparently independent families, three were assigned to group C, and one belonged to group E. This is the first report on XP-E patient in China.

CONCLUSION

Based on the data from the previous 7 cases and the present 4 cases, the distribution of complementation group in Chinese XP patients known at present is: nine XP-C, one XP-F and one XP-E. Although the number of cases is still limited, XP-C appears to be more frequent in China. This forms a marked contrast to Japanese XP patients, who are dominated by XP-A with infrequent presence of XP-C.

Highly selective isolation of unknown mutations in diverse DNA fragments: toward new multiplex screening in cancer

Cancer research would greatly benefit from technologies that allow simultaneous screening of several unknown gene mutations. Lack of such methods currently hampers the large-scale detection of genetic alterations in complex DNA samples. We present a novel mismatch-capture methodology for the highly efficient isolation and amplification of mutation-containing DNA from diverse nucleic acid fragments of unknown sequence. To demonstrate the potential of this method, heteroduplexes with a single A/G mismatch are formed via cross-hybridization of mutant (T-->G) and wild-type DNA-fragment populations. Aldehydes are uniquely introduced at the position of mismatched adenines via the Escherichia coli glycosylase, MutY. Subsequent treatment with a biotinylated hydroxylamine results in highly specific and covalent biotinylation of the site of mismatch. For PCR amplification, synthetic linkers are then ligated to the DNA fragments. Biotinylated DNA is then isolated and PCR amplified. Mutation-containing DNA fragments can subsequently be sequenced to identify type and position of mutation. This method correctly detects a single T-->G transversion introduced into a 7-kb plasmid containing full-length cDNA from the p53 gene. In the presence of a high excess wild-type DNA (1:1000 mutant:normal plasmids) or in the presence of diverse DNA fragment sizes, the DNA fragments containing the mutation are readily detectable and can be isolated and amplified. The present Aldehyde-Linker-Based Ultrasensitive Mismatch Scanning has a current limit of detection of one base substitution in 7 Mb of DNA and increases the limit for unknown mutation scanning by two to three orders of magnitude. Homozygous and heterozygous p53 regions (G-->T, exon 4) from genomic DNA are also examined, and correct identification of mutations is demonstrated. This method should allow large-scale detection of genetic alterations in cancer samples without any assumption as to the genes of interest.

Analysis of DYS19 and DYS287 polymorphisms in the Han population and three other ethnic groups of northeast China

The allelic distribution of the Y-chromosome specific microsatellite DYS19 in the Han population and in the Daur, Oroqen and Ewenki ethnic groups (Northeast China) was analyzed by PCR and denatured polyacrylamide gel electrophoresis. The allelic distribution in the Han population group is as follows: A = 2.90%, B = 26.09%, C = 26.09%, D = 29.98%, E = 15.94%. This allelic distribution differs statistically significant from that observed in the three other ethnic groups (p < 0.05). Furthermore the polymorphism of the Y-chromosome specific Alu insert sequence DYS287 was tested in these four groups. However, no Alu sequence insert was found.

[Genetic diversity and phylogenetic relationships among Chinese Macacas based on protein electrophoresis]

In this paper, using protein electrophoresis method, we studied proteinpolymorphism and genetic divergence of 5 species in Genus Macaca: M. mulatta, M. arctoides, M. assamensis, M. thibetana, M. fascicularis. A total of 30 genetic loci were analyzed for 29 individuals, including 4 Nycticebus pygmaeus as outgroup. For the 19 M. mulatta, 9 loci were found to be polymorphic. Accordingly, the percentage of polymorphic loci, P = 0.3; the mean number of alleles, A = 1.4, and the mean heterozygosity, H = 0.1045, indicating a rather high level of genetic diversity in this species. Furthermore, 10 loci showed polymorphic among the 5 species, which can be used as information loci for phylogenetic reconstruction. Three programs (conml, neighbor, fitch) in PHYLIP 3.5 c were chosen to construct phylogenetic trees. All of the three trees show support a close relationship between M. mulatta and M. fascicularis. However, two trees have the same topology, suggesting that M. arctoides belongs to an independent species group, while M. assamensis and M. thibetana are closely related and belong to another species group, and the other tree gives a different topology which implies that M. arctoides, M. assamensis and M. thibetana belong to one species group.