Objective　To observe the characteristics and rules of craniocerebral injury resulting from a high explosive shell to provide the bases for treating explosive injury. Methods　A total of 36 sheep were distributed at the distance 6 to 48 m away from the explosive center and the shell was exploded electrically at 7 m above the earth. At the same time, the velocity of fragments and shock wave pressure were determined. Gross and pathological observations were performed after injury. Results　Among all sheep with fragment injury, craniocerebral injury was 32%. Their immediate death rate was 75% and all died 6 h later. The incidence rates of penetrating wound and blind wound were 75% and 25% respectively. Pollution of wound track was heavy. The percentage of head lost was 50% in sheep and 50% of injured animal suffered from comminuted fracture of skull base. Bleeding was found extensively on the surface of the cerebrum, even medulla oblongata was involved. Hemorrhage, edema, rupture of small blood vessels and degeneration of neuron were found at the regions 4 cm away from the wound tract with light microscopy. Combined blast injury was found and occurred most often in the abdomen and limbs, both accounting for 62.5%, and combined thoracic injury was the third, up to 50%. All the animals of craniocerebral injury combined with lung blast injury. Conclusion　High explosive shells destroy cranium badly and extensively. Many skulls are lost and the cranial base is readily fractured. The wound track is heavily polluted. Combined injury is more often occurred.

OBJECTIVETo establish a BALB/c nude mouse model with the huamanized chronic myeloid leukemia (CML) for the study of human CML.

METHODSThe BALB/c nude mice aged 4 weeks pretreated by splenectomy, the cyclophosphamide intraperitoneal injection and sublethal irradiation (SLI) were transplanted intravenously with bone marrow mononuclear cells from CML patients. The SLI-pretreated nude mice were divided into 2 groups: group A, in which the nude mice were injected with 0.3 ml PBS; group B, in which the nude mice were infused intravenously with 4.5×10mononuclear cells from CML patients. Then the changes of body weight and appetite were observed, the hemogram and cell morphology were determined, the expressions of human CD13 and CD45 were detected by flow cytometry, the pathologic analysis of bone, liver and intestine were performed by biopsy, and the BCR/ABL fusion gene was detected by RT-PCR.

RESULTSThe mice in group B displayed weakness, auantic, less foodintake and instabiligy of gait as time want on. The average survival time was 46.2±4.2 d (45-57 d). On the third week, the CD13CD45cells accounted for 0.56±0.05% and 2.56±0.36% respectively in group A and B. While on the sixth week, the CD13CD45cells accounted for 0.44±0.07% and 4.97±0.43% in A and B groups respectively, these results showed that cell count in B group was significantly higher than that in A group(P<0.05). Pathological examination showed that the leukemic cells were found in bone marrow of group B. The BCR/ABL fusion gene could be detected in bone marrow.

CONCLUSIONBALB/c nude mouse model with huamanized chronic myeloid leukemia(CML) model has been established by pretreating mice with SLI. The survival time of mice in this model has been long, and the cost to establish the model is low.

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.