Potential implication of activating killer cell immunoglobulin-like receptor and HLA in onset of pulmonary tuberculosis

Killer cell immunoglobulin-like receptor (KIR) and human leucocyte antigen (HLA) play crucial role in maintaining immune homoeostasis and controlling immune responses. To investigate the influence of KIR and HLA-C ligands on the risk of pulmonary tuberculosis (PTB), we studied 200 patients who were confirmed to have PTB and 200 healthy controls on the different frequencies of KIR and HLA-C ligands. Genotyping of these genes was conducted by sequence-specific primer polymerase chain reaction (SSP-PCR) method. Gene frequencies were compared between PTB group and the control group by χ(2) test, and P < 0.05 was regarded as statistically significant. As a result, the frequency of KIR genotype A/B was increased in PTB than controls but A/A was decreased. Moreover, striking differences were observed in the frequencies of HLA-Cw*08 between the two groups. Besides, the frequencies of '2DL2/3 with C1' in PTB were increased compared with control group. In addition, individuals with no KIR2DS3 and no Cw*08 were higher in controls than in PTB. KIR2DS1 was increased in PTB when HLA-C group 2 alleles were missing. In conclusion, KIR and HLA-C gene polymorphisms were related to susceptibility to PTB.

[Prospective study of lethal blood concentration of organophosphorous in humans]

Total cases of organophosphorous (dichlorvos, methamidophos, dimethoate) poisoning outpatients from six hospitals during four years were collected consecutively for lethal blood concentration study. Blood samples were detected with gas chromatography. The probabilities of death, coma were analyzed with Bliss method and their linear regressive equations of probit were obtained respectively, their 50% lethal concentrations (LC50) and 50% coma concentrations(CC50) were calculated by the formulas above. As the death rate was influenced by therapy, its natural death probability has been discussed and estimated their natural LC50 were between the LC50 and CC50 themselves. Combined LC50 and CC50, their natural LC50 were calculated.

[Effects of 6-(alpha alpha-diphenylacetylpiperazinyl) phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone on rabbit platelet aggregation and TXB2, cAMP production]

6-(alpha alpha-diphenylacetylpiperazinyl) phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone (DMDP) is a new synthetic pyridazinone derivative. This compound was shown to inhibit AA, ADP and PAF-induced rabbit platelet aggregation, and its IC50s were found to be 1.12 +/- 0.1, 4.19 +/- 0.5 and 2.97 +/- 0.1 mumol/L, respectively. At the concentration range of 1-500 mumol/L, the compound was found to depress TXB2 content and to increase cAMP levels in washed rabbit platelets in a dose-dependent manner. These might be the mechanisms of the compound on the inhibition of rabbit platelets.

[Comparative observation on the invasiveness of different leukemia cells in various organs in vivo]

Using patho-morphological method and transplantation bio-assay, the in vivo invasiveness of leukemia cells in three transplantable mouse T cell leukemia models was comparatively studied. The results showed that the invasion to the liver was consistent, but that to other organs was obviously different. L615 and L7212 leukemia cells preferred bone marrow and spleen to peritoneum but L7811 leukemia cells were just the opposite. Transplantation bio-assay demonstrated that leukemia cells were present in the bone marrow of L615 mice as early as 6 hours after leukemic cell inoculation, but no leukemia cells were detected in the bone marrow of L7811 mice 2 days after inoculation. In the terminal phase, L615 mice bone marrow became filled with leukemia cells, but L7811 mice bone marrow contained only a few leukemia cells. The difference in invasiveness of leukemia cells into organs is probably related to "homing" receptor. The same type of leukemia cells may possess multiple "homing" receptors.

Treatment of the thalassemia syndrome with splenectomy

Splenectomy was performed on 152 patients with thalassemia (thal), including 90 cases with Hb H disease, 48 cases with homozygous beta-thal, and 14 cases with Hb E-beta-thal. The therapeutic effect in Hb H disease was 83.3%, and 32.3% in Hb E-beta-thal and beta-thal. In Hb H disease, the hemoglobin (Hb) level increased 30 g/l in 14 of 29 cases. After splenectomy, the life-span (T1/2) of 51Cr RBC in Hb H and Hb E-beta-thal increased to 18.2 +/- 2.6 and 18.2 days, respectively. The number of inclusion (Heinz) bodies attached to the RBC membrane increased after surgery. The interdermal delayed supersensitivity reaction became negative in seven of 26 cases of Hb H disease; the IgG also decreased after surgery. The number of PAS positive foam cells in the spleen correlated to Hb level after surgery. Infection is a common complication.