Expression of human interleukin-11 cDNA in E. coli

A 551-bp hIL-11 gene fragment that includes no nucleotide sequences encoding signal polypeptide and the initial 8 amino acids of the mature protein was cloned into a high-level expression vector pEx31B of E. coli. The authors identified the recombinant plasmid, designated pEx31-IL11, by restriction endonucleases digestion and DNA sequencing. The resulting recombinant plasmids were then used to transform E. coli strain HB101, and expression in the PL promoter system, which is temperature-regulated, was achieved. The expressed fusion protein amounts to 50% of total bacterial proteins. The hIL-11 protein expressed in E. coli was fused to the N-terminal 99 amino acids of the MS2 polymerase to form the inclusion body. These recombinant proteins can be purified to about 80% by extracting inclusion body with urea. One IL-6-dependent cell line 7 TD1 was used for bioassay. The recombinant hIL-11 protein was preliminarily purified and renatured to a specific activity of 10(5)U/mg, even in the presence of an excess of a neutralizing anti-IL-6 antibody.

Adaptation of HIV-1 to pigtailed macaques

In vitro infectivity experiments were performed to assess the susceptibility of cells from various monkey species to HIV-1. T lymphocytes from pigtailed macaques, but not those from rhesus or cynomolgus monkeys, were susceptible to infection, but virus expression was limited. The majority of HIV-1 isolates were unable to productively infect pigtailed macaque cells. Inoculation of autologous, HIV-1 expressing cells led to establishment of persistent infection in pigtailed macaques as evidenced by recovery of infectious virus and development of virus-specific antibody responses.

Localization of a gene for progressive myoclonus epilepsy to chromosome 21q22

Progressive myoclonus epilepsy of Univerricht-Lundborg type is a clinically defined entity among the progressive myoclonus epilepsies. It is an autosomal recessive disorder. The underlying biochemical defect is unknown. We used linkage analysis to localize the gene in 12 families with the aid of polymorphic DNA markers. Close linkage was detected with three markers on distal chromosome 21. The loci BCEI and D21S154 gave the highest positive logarithm-of-odds (lod) scores of 5.49 and 4.25, respectively, at zero recombination. The third locus, D21S112, gave a lod score of 6.91 at a recombination fraction of 0.034. There was no evidence of heterogeneity. Multipoint lod scores calculated against a fixed map of the three marker loci gave a maximum four-point lod score of 10.08 at a location of the disease gene at 6.0 centimorgans distal to locus BCEI and 0.8 centimorgan proximal to locus D21S154. As markers BCEI and D21S154 have previously been localized to 21q22.3 by physical methods, our findings place the EMP1 gene locus (for progressive myoclonus epilepsy of the Unverricht-Lundborg type) in chromosome 21 band q22.3. This finding provides an opportunity to test several other epilepsy phenotypes, particularly the so-called Ramsay Hunt syndrome, for linkage to the same locus. It also is a starting point toward isolating and characterizing the gene and its protein product.

X linked neonatal myotubular myopathy: one recombination detected with four polymorphic DNA markers from Xq28

A three generation family with X linked myotubular myopathy (MTM1) was studied with several polymorphic markers from the distal long arm of the X chromosome. A recombination between the disease gene and four markers (loci DXS52, DXS134, DXS15, F8C) from the Xq28 cluster was detected. A new polymorphic marker (U6.2) defining the locus DXS304 in the Xq27-28 region proximal to the Xq28 cluster did not show any recombination with MTM1. These results suggest the following order of loci in distal Xq: cen-DXS42-DXS105-(DXS304, MTM1)-(DXS52, DXS134, DXS15, F8C)-tel.

[Amplification and rearrangement of proto-oncogene c-abl in human leukemia cells]

DNA of peripheral blood or bone marrow leukocytes from 8 normal subjects, 7 cases of acute lymphocytic leukemia (ALL), 2 of acute myelogenous leukemia (AML) and 1 of chronic myelogenous leukemia (CML), having been digested by endonuclease Eco RI or Pst I separately, was hybridized with the probes of 3' fragment (Pst I/Hind III) or 5' fragment (Hinc II/Pst I) of Abelson murine leukemia virus (A-MuLV) oncogene v-abl. The proto-oncogene c-abl, which is homologous to v-abl, was found amplified in 4 ALL, 1 CML and 1 AML. In one of these 4 ALL, c-abl was amplified even over 100 times. A new c-abl BamH I fragment with 6.7 kilobase pairs (kb) in length was observed in 2 ALL and 1 CML out of these 6 cases with amplification, but none of this fragment was found in the normal subjects or other leukemia patients. These 3 patients with the presence of 6.7 kb fragment were high risk ones and 2 of them had died, suggesting that 6.7 kb fragment be the index of poor prognosis. The amplification and rearrangement of c-abl imply the activation of proto-oncogene in leukemogenesis.

Activated c-Ha-ras oncogene with a guanine to thymine transversion at the twelfth codon in a human stomach cancer cell line

The rat fibroblast cell line Rat 1 was transfected with total DNA of a gastrocarcinoma cell line, BGC-823. The transforming gene was cloned from the genomic library of the secondary transformants using in situ hybridization with a probe of the human Alu repeat sequence. This cloned gene is homologous to the protooncogene c-Ha-ras. The activation lesion of the transforming gene was identified by sequence analysis as a single nucleotide substitution of thymine for guanine in the 12th codon. This results in the substitution of valine for glycine at the 12th amino acid of the Mr 21,000 protein.

[DNA transformation activity of a human gastrocarcinoma cell line]

DNAs of three cell lines of human gastrocarcinoma (MGC-803, BGC-823 and PACM-82) and two fresh solid tumors of human stomach cancer were used to transfect NIH3T3 and Rat-1 cells. The transformed cells were selected with high concentration of glucose and low concentration of serum, or with medium containing Geneticin (G418) after co-transfection of pSVneo and DNAs of stomach cancer cell line or primary transformants. From the second round transfection, we had obtained transformants which could grow with high colony forming efficiency in soft agarose and were tumorigenic in nude mice. The southern blot analysis showed that the cellular DNA of the transformants contained human Alu repeat sequence and the transformed gene from stomach cancer cell line (BGC-823) and was homologous to proto-oncogene c-Ha-ras. The transforming gene is able to induce neoplastic transformation of NIH3T3 and Rat-1 cells.

Spatial distribution of [14C]-lidocaine and blood flow in transmural and lateral border zones of ischemic canine myocardium

The purpose of this study was to determine the spatial distribution of lidocaine relative to blood flow in ischemic, normal and border zone canine myocardium. Ischemic zone tissue was distinguished from normal zone tissue by a special microsphere technique in adjacent sections 4 to 5 mm wide from the center to the lateral border of the ischemic region in 14 open chest dogs. Gamma-labeled microspheres were separated by a special technique from carbon-14 ([14C])-lidocaine in the same tissue sample. Blood flow (mean value +/- 1 standard deviation) was reduced to 46 +/- 25 percent of normal in the ischemic subepicardium and 17 +/- 18 percent of normal in the subendocardium. [14C]-lidocaine was 0.56 +/- 0.12 microgram/g in normal myocardium 10 minutes after bolus injection of [14C]-lidocaine; it was reduced to 91 +/- 15 percent of normal in ischemic subepicardium and 58 +/- 12 percent of normal in the subendocardium. Blood flow and lidocaine concentration were uniformly lowest in gross samples from the central and intermediate ischemic zones, and highest in the gross samples from the border normal zone (p less than 0.05). The values for flow and lidocaine in samples from the border ischemic zone were intermediate, that is, higher than values from central ischemic (p less than 0.05) and lower than values from border normal zone samples (p less than 0.05). However, the labeling technique for normal zone tissue revealed that the values of blood flow and lidocaine in the gross samples from the lateral border of the ischemic zone were intermediate between those of adjacent ischemic and normal samples because of the mixture of overlapping normal and ischemic tissues components--not because of a unique mildly ischemic region. Both blood flow and lidocaine concentration were lower in the subendocardial third than in the subepicardial third of the ischemic zone (p less than 0.05) even after the contribution of normal zone tissue was subtracted, suggesting a gradient of ischemia across the transmural border zone. In conclusion, lidocaine is distributed uniformly in ischemic components from the center to the lateral border of the ischemic zone, but there is an endocardial to epicardial gradient. Both lateral and transmural border zone distributions must be considered to understand the mechanisms of drug effects in myocardial ischemia.

Diet and vitamin nutrition of the high esophageal cancer risk population in Linxian, China

In order to examine the nutritional status of the population of Linxian (in Henan, China) known to be at high risk for esophageal cancer (EC), we analyzed blood samples and conducted 3-day dietary surveys on 3 groups of normal adults, age 40-50, from Henan province. Two groups were from Linxian, where the EC mortality rate is about 138/100,000 (Group C, consisting of volunteers with a family history of EC, and Group NC, consisting of those who did not have a family history of EC). The third group, Group F, was from Fanxian, where the EC mortality rate is about 24/100,000. The average plasma retinol level was found to be about 0.27 micrograms/ml in all 3 groups; about 13%-20% of the individuals had a level less than 0.2 micrograms/ml. The average plasma carotene level of all 3 groups appeared to be adequate, ranging from 0.5-1.0 micrograms/ml. About 23% of the subjects in both Groups C and NC had low (less than 2 micrograms/ml) plasma ascorbate levels; in Group F, 16% had low ascorbate levels. Less than 12% of the individuals in each of the 3 groups had erythrocyte glutathione reductase activation coefficients less than 1.2, indicating a widely occurring riboflavin deficiency. Consumption of alcoholic beverages was not found to be a contributing factor to EC. The results of the present study reveal a deficiency of vitamins in the study populations, but do not indicate that the average nutritional status of the volunteers in Group C was worse than that of Groups NC and F with regard to vitamin A, ascorbate, and riboflavin.