Influence of dietary slow-release urea on growth performance, organ development and serum biochemical parameters of mutton sheep

Eighty Dorper × thin-tailed Han cross-bred non-castrated male lambs [mean body weight (BW), 25.87 ± 1.06 kg] were randomly allocated to one of five different concentrations of slow-release urea (urea phosphate, UP). The feed consisted of an equal amount of concentrate diet and roughage; the concentrate feed was formulated to be isoenergetic and isonitrogenic and contained 0%, 1%, 2%, 4% and 8% UP (UP0.0, UP1.0, UP2.0, UP4.0 and UP8.0, respectively) as a replacement for soya bean meal. Feed intake, BW, average daily gain (ADG), feed utilisation efficiency (FUE), absolute and relative organ weights and biochemical and histopathological parameters were measured. Feed intake, BW, ADG and FUE significantly decreased in the group receiving UP8.0 (p < 0.05), but no difference was found among the other groups (p > 0.05). Quadratic equations were developed between the UP dosage in the concentrate feed and ADG or FUE (r²  = 0.973 for ADG and r²  = 0.761 for FUE) to determine the appropriate dosage of UP given the desire to maximise either ADG or FUE, the appropriate dosage (feed concentration) was calculated as 2.01% UP to achieve the greatest ADG or 2.13% UP to achieve the best FUE. The relative weight of the liver (% BW) in the UP2.0 groups was significantly greater than that of UP0.0 (p < 0.05), and the relative weight of the intestine in the UP8.0 was significantly greater than that of UP0.0 (p < 0.05); the relative weight of the carcass, heart, spleen, lung, kidney, rumen, reticulum, omasum and abomasum did not differ among treatments (p > 0.05). The UP8.0 treatment significantly increased serum phosphorus levels (p < 0.05) and decreased the levels of alkaline phosphatase, glucose and calcium (Ca) compared with the lower UP dosage (p < 0.05). No histopathological differences were found in either hepatic tissues or renal tissues among treatments. Dietary UP as a replacement for soya bean in concentrate feeds for mutton sheep should not exceed 4%, as higher dosing may cause malnutrition and mineral disorders.

Orientation-dependent nanostructure arrays based on anisotropic silicon wet-etching for repeatable surface-enhanced Raman scattering

Repeatable fabrication of sensitive plasmonic substrates through a simple procedure has become a major challenge for SERS-based sensing and imaging. Herein, a new class of high-performance SERS substrates, including pyramid, ridged-hexagon, and quasi-triangle nanostructures, is successfully fabricated based on the nanosphere lithography technique and anisotropic wet etching. Using the wafer-scale Cr-hole array as the etching mask, cavity-templates of various configurations are fabricated by the orientation-dependent wet etching technique, from where the nanostructure arrays are finally peeled-off. The anisotropic wet etching on (100), (110), and (111) silicon wafers has been systematically studied at the nanoscale revealing the formation mechanism of these cavity-templates. The peeled-off nanostructure arrays provide high-density tips and/or gaps (about 2.5 × 10(7) mm(-2)) and thus facilitate the generation of "hot spots". The distribution of the electromagnetic field is visualized by the finite difference time domain calculation. And the calculation results are validated by SERS characterization. The SERS enhancement factors of these substrates are in the order of 10(6)-10(7), with the maximum enhancement factor of 1.32 × 10(7) yielded by the ridged-hexagon arrays. The proposed nanostructure arrays present excellent homogeneity and reproducibility (with the largest relative standard deviation of 16.43%) for the reason that the SERS-active substrates are peeled-off from an identical template. The cost-effective fabrication, high sensitivity, good homogeneity and well-performed reproducibility demonstrate that these orientation-dependent NSs are good candidates for SERS-based in vitro and in situ detection and biosensing.

Effects of exogenous protease supplementation on endogenous trypsin activity and gene expression in broilers

Two hundred and forty one-day-old male broiler chickens (Ross-308) were fed corn-soybean basal diets with 0, 40, 80, or 160 mg/kg of an acid protease preparation from 1 to 42 days of age, in order to investigate the effects of an exogenous enzyme on growth performance, pancreatic trypsin activity and mRNA expression. Average daily gain (ADG) was greatest in the 160-mg/kg treatment group at 1-21 days, which was significantly higher than that in the control. After 42 days, average daily feed intake (ADFI) and ADG had significantly increased in the 80- and 160-mg/kg treatments (P < 0.05), with the 80-mg/kg treatment group having the highest ADFI and ADG values. The feed conversion ratio was not affected. Dietary acid protease at 80 and 160 mg/kg significantly decreased trypsin activity in the pancreas (relative to the control group) by 35.71 and 47.29%, respectively (P < 0.05). After 42 days, trypsin mRNA expression in the pancreas had significantly decreased by 19.5% in the 80-mg/kg treatment group relative to the control (P < 0.05). After 21 and 42 days, the diet supplemented with 160 mg/kg acid protease significantly decreased pancreatic trypsin mRNA by 19.6 and 37.7%, respectively, compared to the control. There were the 40-mg/kg treatment group and the control. Our results suggest that the amount of acid protease in the diet significantly affects trypsin activity and mRNA expression in broilers.

Brief reports: TRPM7 Senses mechanical stimulation inducing osteogenesis in human bone marrow mesenchymal stem cells

Mesenchymal stem cells (MSCs) are multipotential stem cells residing in the bone marrow. Several studies have shown that mechanical stimulation modulates MSC differentiation through mobilization of second messengers, but the mechanism of mechanotransduction remains poorly understood. In this study, using fluorescence and laser confocal microcopy as well as patch-clamp techniques, we identified the transient receptor potential melastatin type 7 (TRPM7) channel as the key channel involved in mechanotransduction in bone marrow MSCs. TRPM7 knockdown completely abolished the pressure-induced cytosolic Ca(2+) increase and pressure-induced osteogenesis. TRPM7 directly sensed membrane tension, independent of the cytoplasm and the integrity of cytoskeleton. Ca(2+) influx through TRPM7 further triggered Ca(2+) release from the inositol trisphosphate receptor type 2 on the endoplasmic reticulum and promoted NFATc1 nuclear localization and osteogenesis. These results identified a central role of TRPM7 in MSC mechanical stimulation-induced osteogenesis.

Recognizing the impact of ambient air pollution on skin health

Ambient air pollution is a known public health hazard that negatively impacts non-cutaneous organs; however, our knowledge regarding the effects on skin remains limited. Current scientific evidence suggests there are four mechanisms by which ambient air pollutants cause adverse effects on skin health: (i) generation of free radicals, (ii) induction of inflammatory cascade and subsequent impairment of skin barrier, (iii) activation of the aryl hydrocarbon receptor (AhR) and (iv) alterations to skin microflora. In this review, we provide a comprehensive overview on ambient air pollutants and their relevant sources, and highlight current evidence of the effects on skin.

Meta-analysis of associations between the TP53 Arg72Pro polymorphism with risk of head and neck carcinomas based on case-control studies

Genetic factors have been shown to play a role in the development of head and neck cancers (HNCs). However, studies investigating the association between the TP53 Arg72Pro polymorphism and HNCs susceptibility have yielded conflicting results. Hence, we performed a meta-analysis of all eligible studies (up to January 1, 2012) to derive a more precise estimation of this association in order to increase understanding of the possible risk factors of HNCs. Twenty-seven case-control studies involving 3966 cases and 4387 controls were included in our analysis. Overall, no evidence of association was observed between the TP53 Arg72Pro single nucleotide polymorphism (SNP) and the risk of HNCs in any genetic model (Arg/Arg vs Pro/Pro: odds ratio (OR) = 0.83, 95% confidence interval (CI): 0.65-1.06; Arg/Pro vs Pro/Pro: OR = 0.88, 95%CI= 0.70-1.10; Arg/Arg+Arg/Pro vs Pro/Pro: OR = 0.87, 95%CI= 0.70-1.09; Arg/Arg vs Arg/Pro+Pro/Pro: OR = 0.95, 95%CI= 0.82-1.11). Nevertheless, the TP53 Arg72Pro polymorphism shows diverse effects across different subtypes of HNCs. For example, there was a lack of association of this polymorphism with oral cavity cancer, whereas a significant association with nasopharyngeal cancer was observed. Results of this meta-analysis suggest that the TP53 Arg72Pro polymorphism might have different effects on the risk of various subtypes of HNCs.

Clinical controlled comparison between lobectomy and segmental resection for patients over 70 years of age with clinical stage I non-small cell lung cancer

AIMS

The standard surgical procedure for elderly (≥ 70 years) patients with clinical stage I non-small cell lung cancer (NSCLC) was investigated.

METHODS

A non-randomized prospective controlled study was conducted to compare lobectomy with segmental resection for the treatment of elderly clinical stage I lung cancer patients under different pulmonary function. Perioperative indicators including time and volume of thoracic drainage, incidence of postoperative complications, locoregional recurrence rates, and 1, 3, and 5-year survival rates were analyzed.

RESULTS

A total of 184 patients were included in the study. Patients were classified into two groups according to pulmonary function: group 1 included 64 patients who had poor pulmonary function, with a forced expiratory volume in 1 s (FEV(1)) of less than 1.5 L, whereas group 2 consisted of 120 patients with an FEV(1) ≥ 1.5 L. The patients in group 1 had a longer postoperative mechanical ventilation time and a higher incidence rate of respiratory associated complications than those in group 2 (21.9 vs. 8.35%, p = 0.009). The local recurrence and long-term survival rates were not significantly different between lobectomy and segmental resection. Among the patients who underwent segmental resection, those who had regional lymph node dissection showed a higher 3-year and 5-year survival rate than those undergoing selected lymph node resection (77.8 vs. 51.7%, p = 0.042; 55.6 vs. 27.6%, p = 0.034), but this was not significant in lobectomy.

CONCLUSIONS

Segmental resection combined with regional lymph node resection could be the best choice for elderly clinical stage I NSCLC patients with FEV(1) < 1.5 L.

Electrochemical isothermal-capacitance-transient spectroscopy: a new depth profiling method of deep levels

The authors report on a new depth profiling method of deep levels, which we call electrochemical isothermal-capacitance-transient spectroscopy (EICTS). This is combined with electrochemical capacitance-voltage using the Schottky barrier of etchable electrolyte and isothermal-capacitance-transient spectroscopy using the capacitance-transient profile at a fixed temperature. We proved its validity by applying to the ZnSe:N epitaxial film of thickness of more than 1000 nm and comparing the characteristics of an obtained deep level with the results measured by conventional deep-level detection techniques. It is expected that EICTS is very effective to assess the deep levels of wide-bandgap semiconductors that suffer from various point defects and their complexes.

Transferrin and haemoglobin polymorphism in domesticated goats in the USA

The distribution of transferrin (Tf) and haemoglobin (Hb) polymorphisms in five goat breeds in the USA is reported. Two Tf types, A and B, were identified. A significant difference in frequency (P less than 0.05) was observed only between the Spanish and Alpine goats. Haemoglobin beta-globin variants, Hb beta A, Hb beta D and Hb beta E were observed with isoelectric focusing at pH ranges 5-8 and 6.7-7.7. Hb beta D was not found in the Alpine and Angora breeds. Haemoglobin allelic frequencies varied widely and differed significantly (P less than 0.05) among breeds.

Construction and identification of an antisense glucose transporter-1 plasmid

Our aim was to construct a pcDNA3.1(+) eucaryotic expression system vector containing the antisense glucose transporter-1 (Glut-1) gene. Total RNA was isolated from human Hep-2 laryngeal carcinoma cells, and the Glut-1 and antisense Glut-1 sequences were amplified by polymerase chain reaction. Expression plasmids containing the sense and antisense cDNA were constructed using the pcDNA3.1(+) vector. The resulting sense and antisense vectors, pcDNA3.1(+)-Glut-1 and pcDNA3.1(+)-antiGlut-1, respectively, were examined by restriction analysis and DNA sequencing. The pcDNA3.1(+)-antiGlut-1 was subsequently transfected into Hep-2 cells. AntiGlut-1 mRNA expression was detected, indicating the successful construction of an antisense Glut-1 plasmid capable of transfecting Hep-2 laryngeal carcinoma cells. These data provide a firm basis for additional studies using the plasmid pcDNA3.1(+)-antiGlut-1 to determine its therapeutic potential for the treatment of laryngeal carcinoma.

Primary malignant myoepithelioma of the left maxillary sinus: a case report

We describe the case of a 41-year-old woman who presented with a malignant myoepithelioma (MME) in her left maxillary sinus. Exploratory biopsy of the left maxillary sinus was performed and pathological examination demonstrated that the tumour was positive for calponin and cytokeratin 14, which are indicative of MME. Lateral rhinotomy and left total maxillectomy were undertaken and the patient received radiotherapy and chemotherapy post-surgery. Primary recurrence and metastasis to the left angle of the mandible occurred 9 months after the surgery. The patient died of cachexia 13 months after the surgery.

Whole genome expression profiling of hepatitis B virus-transfected cell line reveals the potential targets of anti-HBV drugs

Hepatitis B virus (HBV) infection is a major health concern world wide, and few effective treatments have been developed. It has recently been reported that inhibiting host-cell proteins can prevent viral infection. The human genome may contain more genes required for HBV infection and replication than the viral genome. A systematic approach to find these potential antiviral targets is by host gene expression analysis using DNA microarrays. The aim of this study was to identify and validate novel cellular anti-HBV targets. The Human Whole Genome Bioarray was used to analyze differentially expressed genes in HepG2.2.15 cells and HepG2 cells. Altered gene expression in HepG2.2.15 cells was studied following treatment with the anti-HBV drug, lamivudine. Genes that were differentially expressed during HBV infection and reversed with anti-HBV drugs were validated by semiquantitative reverse transcription-PCR. Bioinformatics analysis revealed ABHD2, EREG, ACVR2B, CDC34, KHDRBS3 and RORA as potential cellular anti-HBV targets. Antisense oligodeoxynucleotides were used to test the antiviral activity of these potential targets. Results strongly suggested that inhibition of ABHD2 or EREG significantly blocked HBV propagation in HepG2.2.15 cells. This study demonstrates that ABHD2 and EREG are essential for HBV propagation and provides strong evidence that these proteins could be used as potential targets for anti-HBV drugs.

Telomerase antisense inhibition for the proliferation of endometrial cancer in vitro and in vivo

The objective of this study was to investigate the antitumor effect of antisense telomerase oligodeoxynucleotides to endometrial cancer cells in vitro and in vivo. Antisense oligodeoxynucleotides (ODNs) against the human telomerase transcripatse (hTERT) synthesized to serve as telomerase inhibitors. Reverse transcription–polymerase chain reaction and 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide (MTT) assay were used to test the expression of hTERT messengerRNA (mRNA) and inhibition of cell proliferation in vitro. In vivo, antitumor effects of ODNs or combined with cisplatin were evaluated in endometrial cancer xenograft. Telomerase activity was tested by telomeric repeat amplification protocol. Antisense ODNs could inhibit proliferation of human endometrial cancer cells (HEC-1-A) in vitro, and downregulate the expression hTRET mRNA in a dose- and period-dependent manner. The tumor growth inhibitory rate of low- and high-dose ODNs were 34.20% and 89.21%, and combined group was 75.30%. Telomerase activity was downregulated to 87.32% compared to the control in the ODNs-treated xenograft tumors. Antisense oligonucleotides of hTERT effectively inhibit the growth of endometrial cancer cell line. Telomerase inhibitor might be a new strategy for chemotherapy or chemoprevention in endometrial cancer.

Antisense oligonucleotides targeted against asialoglycoprotein receptor 1 block human hepatitis B virus replication

Chronic hepatitis B virus (HBV) infection is a major worldwide public health problem. Better therapeutics and treatment strategies are urgently needed because of ineffective clinical treatment. Our previous study showed that asialoglycoprotein receptor 1 (ASGPR1) was upregulated by HBV but downregulated by lamivudine in HepG2.2.15 cells. It has also been reported that ASGPR is a candidate receptor for HBV attachment to hepatocytes. Therefore, as a major subunit of ASGPR, ASGPR1, might be a potential target for anti-HBV drugs. To validate this hypothesis, antisense oligonucleiotides (ASODNs) were used to downregulate ASGPR1 level in HepG2.2.15 cells. By using the MFOLD web server and BLAST searches, five ASODNs theoretically targeting ASGPR1 were selected. After 72 h post-transfection, HBV-DNA level in cell medium were examined by real-time polymerase chain reaction (PCR). Hepatitis B surface antigen (HBsAg) and Hepatitis B e antigen (HBeAg) were detected using enzyme-linked immunosorbent assay (ELISA). ASGPR1 mRNA and protein level were measured by semi-quantitative reverse transcriptase (RT)-PCR and Western blot analysis respectively. The results showed that ASODN2 significantly downregulated ASGPR1 level. It also reduced HBV-DNA, HBsAg and HBeAg level in cell medium as observed with lamivudine. In contrast, the sense sequence and scrambled sequence of ASODN2 had no effect on ASGPR1 and HBV markers in HepG2.2.15 cells. This indicated that ASODN2 could specifically reduce HBV replication in vitro. Additionally, cell proliferation and apoptosis assay suggested that downregulation of ASGPR1 did not affect cell viability. We, therefore, proposed that ASODNs targeted against ASGPR1 could block HBV replication without the influence of other changes, and ASGPR1 could be targeted for anti-HBV drug development.

Differentially expressed cellular genes following HBV: potential targets of anti-HBV drugs?

The aim of the study was to screen for cellular genes that are differentially expressed following hepatitis B virus (HBV) infection, in an attempt to identify potential targets of anti-HBV drugs. An oligonucleotide microarray containing 231 virus-infection-associated genes was prepared. Differential gene expression in HepG2.2.15 cells compared to control with HepG2 cells was analysed by this in-house microarray. The change in gene expression in HepG2.2.15 cells treated by lamivudine on days 4 and 8 after exposure was also studied. Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was used to comfirm the differentially expressed genes induced by HBV and lamivudine. There were 31 upregulated and four downregulated genes in HepG2.2.15 cells compared with the HepG2 control cells. Eleven genes were consistently altered by lamivudine at both time points. Of the 31 genes that were upregulated in HepG2.2.15 cells, there were seven genes which were downregulated by lamivudine. Of the four downregulated genes, there was one gene which was upregulated by lamivudine. Of the differentially expressed genes induced by HBV and lamivudine, the expression of five genes was confirmed by semi-quantitative RT-PCR. These results shed new light on the effects of HBV and lamivudine on cellular gene expression. Differentially expressed genes induced by HBV and lamivudine could potentially become new anti-HBV drug targets in novel therapies.

Oligonucleotide microarray for HLA-DRB1 genotyping: preparation and clinical evaluation

In this study, HLA-DRB1 gene was genotyped by using the microarray technique. Oligonucleotide probes were designed based on partial sequences of various genotypes of HLA-DRB1, and were fixed on a silylated slide to form a microarray. The second exon of HLA-DRB1 gene in the extracted genomic DNA samples was amplified and labelled by means of polymerase chain reaction (PCR); then it was hybridized to the microarray. The microarray was scanned, and the result was analysed in order to determine the genotypes of HLA-DRB1 of the tested sample. A total of 1574 of 1592 clinical samples had accordant results of genotypes in either microarray assay or PCR-SSP assay; 8 of 10 samples that had inconsistent results of genotypes were proved to be microarray-assay reliable by confirmation of DNA sequencing. It is concluded that microarray is an alternative reliable method for HLA-DRB1 genotyping.

HBx protein of hepatitis B virus (HBV) can form complex with mitochondrial HSP60 and HSP70

HBx, a transcriptional transactivating protein of hepatitis B virus (HBV), is required for viral infection and has been implicated in virus-mediated liver oncogenesis. However, the molecular mechanism for its influence on cell remains largely unknown. It was proved that HBx need the help of host cell proteins to exert its function by binding to them. During purifying of GSTX (fusion protein of GST and HBx) expressed in E. coli, we found that it can bind specifically with GrpE (HSP60) and DnaK (HSP70) of E. coli while GST cannot. Using GST pull-down, two-dimensional gel electrophoresis and mass spectrum, we found that GSTX can also bind to human mitochondrial HSP60 and HSP70, which are homologues of GrpE and DnaK. These interactions between HBx and mitochondrial HSP60 and HSP70 are supported by the result of co-immunoprecipitation experiment. It means that HBx can form complex with E. coli and human HSP60 and HSP70. The implication of HBx, HSP60 and HSP70 complex in molecular mechanism of virus infection is discussed.

Quantification of the relative levels of wild-type and lamivudine-resistant mutant virus in serum of HBV-infected patients using microarray

During the course of lamivudine administration in hepatitis B virus (HBV)-infected patients, a dynamic development of the viral population in serum is observed. Total HBV level is initially reduced, then lamivudine-resistant mutants appear, and finally, the viral level is increased. All methods of mutant detection so far described can only identify mutants in the serum, and cannot determine the proportion of those mutants. In this paper, we report the development of a novel technique that can quantify the relative proportion of mutants in serum utilizing gene microarray technology. Based on the nucleotide sequence at the loci of the mutations in lamivudine-resistant HBV mutants, 28 probes were designed and dotted on glass film to prepare the oligonucleotide microarray. Ten standard curves were established by employing 15 reference plasmids as templates. Ten standard math functions were simulated, which allowed quantification of the proportion of mutants in the sample by measuring the value of fluorescent intensity on the microarray. By utilizing the standard math function, the relative proportion of two different mutation sequences in the mixed template could be detected with an error <10%. The HBV-lamivudine oligonucleotide microarray is reliable to quantify the relative proportion of wild-type HBV vs HBV mutants in patient's sera.

[Gene typing of merozoite surface protein 1 of Plasmodium falciparum isolates from Hainan Province]

OBJECTIVE

To identify the genotype of merozoite surface protein 1 (MSP1) of Plasmodium falciparum isolates from Hainan Province.

METHODS

Nested PCR was applied to amplify the MSP1 of Blocks 2 and 3 Plasmodium falciparum isolates from Hainan Province. Two allelic family representative gene fragments were sequenced.

RESULTS

From 36 out of 39 blood samples from Plasmodium falciparum patients, 44 gene fragments of blocks 2 and 3 of the MSP1 were amplified, of which the MAD20-type allele was dominant(75%). followed by K1-type allele. No RO33-type allele was found. The mixed infection rate of the two different allelic type was 19.4%. Sequence analysis showed that the sequences of MAD20- and K1-type isolates from Hainan Province were highly homologous to that of the MAD20 and K1 allelic prototypes.

CONCLUSION

Two principal allelic types of MSP1 gene, MAD20- and K1-type, exist in malaria endemic areas in Hainan Province, the MAD20-type being the dominant.

[Investigation on genotype constitution of different Plasmodium vivax isolates and its geographical distribution in China]

OBJECTIVE

To investigate the population constitution and geographical distribution of Plasmodium vivax in China using molecular technique.

METHODS

Blood-spot filter paper samples with related epidemiological data were collected from vivax malaria patients living in malarious area of 10 provinces (autonomous region) in China. Semi-nested- or nested-allelic-specific PCR genotyping method was used to identify CSP genotypes, families and types of Plasmodium vivax of each isolate from these patients.

RESULTS

Of 384 field isolates of Plasmodium vivax, 258 temperate zone family strains were identified, including 14 allelic variant genotypes spreading among 10 sampling provinces; allelic variants sized less than 731 bp were only seen in 5 provinces in southern China; 79 tropical zone family strains including 5 genotypes were also distributed in 5 provinces of southern China south to 25 degrees N. lat; and 14 PV Type-2 strains including 2 genotypes were found in some areas of Hainan and Yunnan Provinces. In addition, 33 isolates from genotype-mixed infections were revealed.

CONCLUSION

At present, area north to 25 degrees N. lat. of the country is the sole area prevalent for Plasmodium vivax family strains of temperate zone; there is overlapping distribution of P. v. of temperate zone family and tropical zone family of this parasite in the southern China south to 25 degrees N. lat; where the most complex isolate constitution is in Yunnan and Hainan Provinces, and PV Type-2 strains have been found in some areas of the two provinces. Besides, there were 2 groups of genotype with distinct geographic distribution feature within the temperate zone family.

[Studies on identification of circumsporozoite protein genotyping of Plasmodium vivax]

OBJECTIVE

To develop a new method of genotyping circumsporozoite protein (CSP) gene for identification of field isolates of Plasmodium vivax.

METHODS

Improved Chelex-100 ion-exchange method was used to extract DNA from blood filter paper samples, nested PCR and allele-specific PCR techniques, agarose gel electrophoresis analysis and dot/southern blotting-probe hybridization were employed for amplification, resolution and identification of the diagnostic fragments.

RESULTS

Using the nest-allele-specific PCR assay reported here, small amounts of DNA extracted from a piece of blood filter paper sample were amplified which produced three different size ranges of diagnostic bands: 650-770 bp PV-species-specific band, 170-230 bp diagnostic band for temperate zone family and 588 bp band for PV type-2. The sizes and patterns of the bands produced by the reference strains were consistent with those of designed target sequences. Of 59 examined isolates from 6 provinces of China, 42 temperate zone family strains, 15 tropical zone family strains and two PV type-2 strains were identified.

CONCLUSION

1, Three genotype strains of P. vivax mentioned above could be identified by this method with only two rounds of PCR and without probe hybridization. 2, The preliminary results showed that PV type-1 including temperate zone family strains and tropical zone family strains as well as PV type-2 strains are present in China. In addition, another CSP genotype with both sequence characteristics of temperate zone and tropical zone family might also be present in China.