Analysis of lactate dehydrogenase gene polymorphisms and prediction of B cell epitopes in four human Plasmodium species / 中国血吸虫病防治杂志

Objective To analyze the polymorphism of Plasmodium lactate dehydrogenase (pLDH) gene and predict B-cell epitopes in pLDH peptides in four species of human malaria parasites. Methods The blood samples and epidemiological characteristics were collected from malaria cases in Yunnan Province registered in the National Notifiable Disease Report System. The pLDH genes of four human Plasmodium species were amplified using nested PCR assay and sequenced. The polymorphisms of pLDH genes was analyzed using the software MEGA version 7.0.26 and DnaSP version 5.10, and the B-cell epitopes were predicted in pLDH peptides using the Immune Epitope Database (IEDB). Results The sequences of P. vivax LDH (PvLDH), P. falciparum LDH (PfLDH), P. ovale LDH (PoLDH) and P. malariae LDH (PmLDH) genes were obtained from 153, 29, 17 and 11 blood samples from patients with P. vivax, P. falciparum, P. ovale and P. malariae malaria, respectively, which included 15, 2, 4 and 2 haplotypes and had a nucleotide diversity (π) of 0.104. A high level of intra-species differentiation was seen in the PoLDH gene (π = 0.012), and the π values were all < 0.001 for PvLDH, PfLDH and PmLDH genes. Active regions of B-cell antigen were predicted in the pLDH peptide chain of four human malaria parasites, of 4 to 5 in each chain, and the activity score was approximately 0.430. Among these peptide chains, the “86-PGKSDKEWNRD-96” short-peptide was a B-cell epitope shared by all four species of human malaria parasites, and the “266-GQYGHS (T)-271” short-peptide was present in PvLDH and PoLDH peptide chains, while “212-EEVEGIFDR-220” was only found in the PvLDH peptide chain, and “208-LISDAE-213” was only seen in the PfLDH peptide chain. Conclusions The PoLDH gene polymorphism may be derived from the weak negative purification selection, while PvLDH, PfLDH and PmLDH genes may maintain a relatively conservative state. There may be two B-cell epitopes “212-EEVEGIFDR-220” and “208-LISDAE-213” in the proximal region of the C terminal in the pLDH peptide chain, which is feasible to differentiate between P. vivax and P. falciparum infections.

Demoralization and depression in Chinese cancer patients.

OBJECTIVE: Demoralization and depression are common in cancer patients and closely related to suicide. But the association and difference between them are not clear. The aim of this study is to investigate demoralization and depression in Chinese cancer patients. METHODS: This study is a cross-sectional study. Two hundred ninety-six cancer patients completed the questionnaire. First is using the DS-II to evaluate demoralization in advanced cancer patients and using the PHQ-9 to evaluate their depression. Then determine the association between demoralization and depression by Pearson rank correlation test. Finally, an ANOVA was conducted using DS-II as the categorical variable and PHQ-9 as the continuous variable and using PHQ-9 as the categorical variable and DS-II as the continuous variable. RESULTS: There is a positive association between demoralization and depression. A special case that patients with high demoralization but low depression was discovered, which accounted for a large proportion. CONCLUSION: Demoralization and depression are two different psychological states, which require medical staff to identify and take corresponding intervention measures in time. Patients with high demoralization but low depression require further attention.

[Geographical features of malaria in Yunnan Province].

OBJECTIVE: To understand the geographical features of malaria in Yunnan Province, so as to provide the reference for malaria elimination. METHODS: The data of malaria in Yunnan Province from 2012 to 2015 were collected and analyzed. RESULTS: Totally 2 586 malaria cases were reported in Yunnan Province from 2012 to 2015, in which 274 (10.60%) were local cases and 2 311 (89.37%) were abroad imported, and one (0.03%) was domestic imported. The imported malaria cases and local cases were analyzed according to the sources and locations respectively, and the arithmetic means of the numbers of imported and local cases were 96.29 and 10.96 respectively, the standard deviations of the numbers of imported and local cases were 421.18 and 19.12 respectively, and the difference of the means was not significant (Z = - 0.326, P > 0.10). Both the imported and local malaria cases could be clustered into five sections by the number of 5. The Herfendal-Hirshman indexes of the imported and local malaria cases were 8 121 and 1 598 respectively. CONCLUSIONS: There is no significant difference of the distribution between the imported and local malaria cases, and they should be attaching equal importance. The non-uniform degree of imported cases is higher than that of the local cases, while both of them could be divided into five major clusters in the prevention and control work.

[Analysis of polymorphism of Pfhrp2 gene in Plasmodium falciparum from falciparum malaria patients in Yunnan Province].

OBJECTIVE: To analyze the polymorphism of histidine rich protein 2 (HRP II) gene in Plasmodium falciparum (Pfhrp2) from falciparum malaria patients in Yunnan Province, so as to lay the foundation for studying the defection of antigen genes of Plasmodium. METHODS: The filter paper blood samples and related information of falciparum malaria cases reported were obtained in Yunnan Province from August 2012 to September 2015. Under the guidance of the specific primers, the exon2 regions in Pfhrp2 gene in P. falciparum from DNA samples were amplified by PCR, and the PCR products were sequenced. The sequences of exon2 region in Pfhrp2 gene were blasted by comparing with the reference sequences AY816237, AY816240, and AY816301. Next, the polymorphism of the sequence in exon2 region of Pfhrp2 gene was analyzed by MEGA 5.04 software. The conserved sites and genetic distances between sequences were calculated by using the software as well, and the clustering tree was drawn according to the genetic distances between the amino acid sequences. RESULTS: A total of 218 bloods samples from the falciparum malaria cases in 15 prefectures of Yunnan Province were collected, and the sources of infection included Yunnan, Africa and Myanmar. The PCR results showed that the exon2 regions in Pfhrp2 genes of 155 samples were positive by amplification and their products were sequenced successfully. The sequence analysis showed that the length range of the amino acid residues of exon2 region in Pfhrp2 gene was from 115 aa to 298 aa, the average length was 239.7 aa. There was no statistically significance among the means of the amino acid residues of the isolates from Africa (239.9 aa), Myanmar (239.5 aa) and Yunnan (241.6 aa) (F = 0.025, P > 0.05). All the 155 amino acid sequences ended with type 12 repeat, 98.1% (152/155) of them started with type 1 repeat and 1.9% (3/155) of them started with type 2. Type 2 presented most frequently repeat in all the sequences and the average repeat times were 12.9. The homologous locus of the DNA sequences in exon2 regions of the 155 Pfhrp2 genes was 894 bp, among which the conservative sites accounted for 20.6% (186/894), and the variable sites for 78.2% (699/ 894). The genetic distances between the sequences of Africa isolates ranged from 0 to 0.741, and those of the Myanmar and Yunnan isolates were 0-0.948 and 0-0.750, respectively. The cluster analysis showed that all the 155 sequences clustered into 3 categories on genetic distances between amino acid sequences according to the size of the amino acid sequence length. At the same level, the sequences had approximate lengths and amino acid repeat types. CONCLUSIONS: The sequence of exon2 region in Pfhrp2 gene of P. falciparum from falciparum malaria cases in Yunnan Province is highly polymorphic, the P. falciparum isolates are clustered mainly according to the size of the amino acid sequence of exon2 region in Pfhrp2 gene.

Stress and continuous relaxation spectrum of porcine cornea after LASIK / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To explore the characteristic of relaxation of porcine cornea after LASIKMETHODS: Usual LASIK was performed on fresh porcine corneas with stable intraoculer pressure (IOP) maintained through optic nerve irrigation. The ablation depth on stroma is 30%, 50% and 70% respectively. Then the dumbbell-shaped corneal strip specimens were cut and stored in 20% Human Albumin solution for use (4℃).Sip up the Albumin solution on specimens, and fixed them on homemade jig. Stress relaxation tests were erformed on Tytron250 Dynamics Experiment System. the loading speed was 385mm/min,extending ratewas 1.5, and relaxation time was 1 000s. The data werecollected electronically and automatically.RESULTS: In LASIK procedure, though a single flap-cutting can cause a little reduction of corneal stress relaxation (P＜0.05,P=0.49), the cornea may still remain its property of visco-elasticity. When ablation depth was 30% or more, corneal stress relaxation decreased to almost one half (P＜0.01).The change of corneal stress relaxation degree in vertical meridian specimen was lower than that in horizontal specimen, especially when ablation depth was 70%, and it's statistically significant (P＜0.001). In LASIK operation, the more depth the ablation, the more reduce the stress relaxation degree, and it's easy to cause deformation and creep deformation.CONCLUSION: The changes of the stress relaxation in verticai and longitudinal meridian specimens are similar, and slightly obvious in longitudinal specimen, especially in 70%ablation group.

The effect of amniotic membrane transplantation on rabbit conjunctival surface reconstruction at the recovering stage of alkali burn / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: (1) To investigate the effect of amniotic membrane transplantation (AMT) on rabbit conjunctival surface reconstruction with severe alkali burns. (2) To evaluate the possibility of AMT treatment for ocular alkali burns during recovering stage.METHODS: Animal models were established on 30 eyes of rabbits by creating severe alkali burns on the conjunctiva from the upper corneal limbus to the upper conjunctival fornix.Preserved human amniotic membrane transplantations and reconstruction of conjunctival fornix were performed at one week after injury (recovering stage). Epithelium growth of burned area after transplantation was observed using light microscope at 1, 2, 3, 4, and 8 weeks. Conjunctival tissue in transplantation area was collected at 1, 4 and 8 weeks. The ultrastructure of the collected tissue was studied by electron microscope. The results were compared with control group,which received only vitamin C subconjunctival injection and antibiotic eye drops as treatment for alkali burn. Exterior eye pictures were also taken at the end of the observation, the width from upper corneal limbus to the edge of upper fornix was measured. Data was analyzed statistically.RESULTS: 1) Tn the transplant group, conjunctival epithelium growth was observed in the area of AMT under both light and electron microscope 1 week after surgery. At 4weeks, conjunctival epithelium with goblet cells that resembled normal conjunctival tissues was observed in the whole amniotic membrane area. At 12 weeks, the conjunctival epithelium on the amniotic membrane was well formed, and the connective tissue under the epithelium was loose at the fornix. No fibrosis was identified. In contrast, conjunctival epithelium necrosis was observed in the control group at 2weeks after alkali burns. Re-epithelization did not occur through the 12-week observation. Severe fibrosis with inflammatory cells infiltration was observed between 4 to 8weeks. At 12 weeks, fibrosis of the connective tissue at the fornix developed and there were no conjunctival epithelium covering the burned area. 2) In the transplant group, the conjunctiva in transplanted area had no scarring and appeared smooth at 12 weeks. Upper fornix was reconstructed. The depth of fornix was 7.9±0.3mm (7.6-8.2mm), which was approximate to the normal depth 8.2±0.2mm (8.0-8.4 mm,P＞.05). While in the control group, the burned area appeared rough with granuloma formation and severe scarring. Upper fornix became shallow. The depth of fornix was 3.1±1.7mm(1.0 to 4.5mm.), and significant difference was found between control and transplant group (P＜0.01).CONCLUSION: Human amniotic membrane preserved in glycerin can promote cell adhering, migrating and differentiating of normal conjunctival epithelium.Reconstruction of conjunctival surface in early stage of alkali burn can be achieved by AMT. AMT can effectively prevent symblepharon formation.

Chemical constituents of Geranium eristemon / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents of Geranium eristemon.</p><p><b>METHOD</b>Chromatography and spectral analysis were used to isolate the constituents and elucidate their structures.</p><p><b>RESULT</b>Five compounds were isolated from acetone extract of the whole grass of G. eristemon, and identified as beta-sitosterol, protocatechuic acid, myricetin, kaempferol-7-O-alpha-L-arabifuranoside and kaempferol-3-O-alpha-L-arabifuranoside.</p><p><b>CONCLUSION</b>kaempferol-7-O-alpha-L-arabifuranoside and kaempferol-3-O-alpha-L-arabifuranoside were isolated from G. genus for the first time.</p>