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J Sorge

Publications and source records attributed to J Sorge.

36 records · Page 2Linked to original sources
PubMed1986

Cloning and sequence determination of a human rheumatoid factor light-chain gene.

The contribution of germ-line variable regions to autoantibody formation in humans is poorly understood. To study the gene structure of a human autoantibody, chronic lymphatic leukemia (CLL) cells from a patient with an IgM anti-IgG (rheumatoid factor, RF) paraprotein were utilized. The rearranged immunoglobulin gene encoding the kappa light chain for the RF was cloned, and the nucleic acid sequence of its variable region was determined. As demonstrated by Southern blot analysis using a kappa joining-region probe, the CLL cells, stable CLL-WIL2-729-HF2 RF-secreting hybridomas, and the cloned light-chain gene all had an identical restriction fragment containing the rearranged light-chain gene. The CLL RF light chains reacted weakly with an antipeptide antibody against a primary structure-dependent idiotype present on the light chains of the majority of IgM RF paraproteins. The nucleotide and predicted amino acid sequences of the CLL light-chain gene place it in the kappa III variable-region subgroup, and a comparison to known RF paraproteins reveals marked homology to the light-chain amino acid sequence of the IgM RF paraprotein Pom. Both Pom and the CLL light chain appear to identify a second kappa III gene or gene group that is able to encode RF paraprotein light chains.

Amino Acid Sequence↗
PubMed1985

Heterogeneity in type I Gaucher disease demonstrated by restriction mapping of the gene.

A cloned fragment of human glucocerebrosidase cDNA has been used as a probe to study restriction polymorphisms in the region of the gene for Gaucher disease. Variability in the size of fragments produced by digestion with the restriction endonucleases Pvu II and Kpn I was discovered. The Pvu II polymorphism was found to be a very prevalent one with a gene frequency of 0.65 for the Pv1.1- allele and 0.35 for the Pv1.1+ allele. Similar frequencies were encountered among diverse ethnic groups. Five of eight Jewish patients with Gaucher disease were found to be heterozygous for the Pvu II restriction polymorphism. One non-Jewish patient with type I Gaucher disease was heterozygous for the Kpn I variant. The existence of Gaucher disease genes in association with either allele of the ancient Pvu II polymorphism clearly indicates that, even within the Jewish population, the Gaucher disease mutation has occurred independently more than once. Presumably, different mutations have also occurred in the non-Jewish population.

Amino Acid Sequence↗
PubMed1985

Molecular cloning and nucleotide sequence of human glucocerebrosidase cDNA.

Mutations in the human glucocerebrosidase gene cause Gaucher disease. A cDNA clone containing the entire human glucocerebrosidase coding region from normal cells has been isolated using lambda gt11 expression libraries. The complete nucleotide sequence, a restriction map, and a hydropathy profile are presented. Hybridization to chromosome-specific DNA localizes the human glucocerebrosidase gene to chromosome 1. The likely precursor protein is 515 amino acids long. The NH2-terminal 19 amino acids constitute a leader sequence that is cleaved from the mature protein. The predicted molecular weight of the mature protein is 55,384, without glycosylation or carboxyl-terminal processing.

Amino Acid Sequence↗
PubMed1985

Glucocerebrosidase "processing" and gene expression in various forms of Gaucher disease.

Immunoblots were prepared using extracts of fibroblasts derived from five controls and from four unrelated patients with type I, three with type II, and two with type III Gaucher disease. Five monoclonal antisera and two rabbit sera, crude and affinity purified, were utilized to detect antigen transferred to nitrocellulose paper. Only a band of 63,000 molecular weight (Mr) was consistently detected. We found no 56-K band either in normal or in Gaucher disease fibroblast extracts. Thus, using a variety of antisera, we are unable to verify the claim that the types of Gaucher disease can be differentiated from one another by immunoblotting.

Cell Line↗
PubMed1984

Cross-reacting material in Gaucher disease fibroblasts.

Glucocerebrosidase is the enzyme that is deficient in Gaucher diseases. Four monoclonal antibodies reacting with at least two different epitopes of this enzyme have been produced. The amounts of glucocerebrosidase in fibroblasts of patients with all three types of Gaucher disease were investigated by radioiodinating two of the antibodies and measuring their binding to fibroblast extracts immobilized on nitrocellulose filters. The amount of glucocerebrosidase antigen was decreased in all cases of Gaucher disease, particularly in the fibroblasts of patients with the more severe neuronopathic forms of the disorder, types II and III. The catalytic activity was reduced to a greater extent than the amount of antigen in all cases, so that the specific activity of the residual enzyme was found to be diminished. Although measurements in individual cases were quite reproducible and the amount of antigen detected by monoclonal antibodies reacting with different epitopes was quite similar, there was considerable variation between patients. This finding is consistent with the apparent within-type genetic heterogeneity of Gaucher disease, even within the Ashkenazi Jewish population in which it is most prevalent.

Antibodies, Monoclonal↗
PubMed1984

Integration-specific retrovirus expression in embryonal carcinoma cells.

The undifferentiated embryonal carcinoma (EC) cell line PCC4 aza 1 was infected with a selectable amphotropic retrovirus. Although EC cells are generally refractory to retroviral gene expression, we found that approximately 1 of 5,000-10,000 recombinant proviruses was transcribed in these cells. Cells containing an active recombinant provirus were cloned and expanded. Nucleic acid analysis revealed approximately one intact provirus per cell. Viral RNA levels were different for each cell clone examined [between 0.05% and 0.5% of the poly(A)+ RNA], and transcription was initiated and terminated in the long terminal repeats as in permissive differentiated cells. The cells retained an undifferentiated phenotype and remained positive for stage-specific embryonic antigen 1 and negative for H-2 surface antigens. The cells retained the block to the expression of other proviruses integrated at other chromosomal locations. The data suggest that a cis-acting genetic element, at or near the chromosomal site of integration, or mutations in the viral control elements themselves may be responsible for provirus expression in these cells.

Animals↗
PubMed1984

Amphotropic retrovirus vector system for human cell gene transfer.

Retroviral vectors have been constructed for gene transfer in mammalian and avian cells, however most retroviral vector systems are complicated by the spread of a replication-competent helper virus. This problem has been circumvented by segregating the viral genome into cis- and trans-acting components. By establishing helper cell lines that produce the trans-acting viral gene products, one can propagate the cis-acting component in them and harvest defective viral particles that contain only the cis-acting component. The cis-acting component can provide a useful vehicle for the highly efficient transfer of genes into target cells. The defective vector systems described to date, however, are restricted in host range to murine, avian, rat, and dog cells. We describe a helper-free vector system based entirely on an amphotropic murine virus with a wide mammalian host range, including the ability to carry out efficient gene transfer into human cells. We also describe a double mutation constructed in the trans-acting genome which reduces the frequency of replication-competent recombinant viruses to undetectable levels.

Animals↗
PubMed1983

cis-Acting RNA packaging locus in the 115-nucleotide direct repeat of Rous sarcoma virus.

The v-src gene of Schmidt-Ruppin strain A of Rous sarcoma virus is flanked by a 115-nucleotide direct repeat. Mutants that lack either the upstream or downstream copy replicate normally. However, mutants that lack both copies do not replicate. Cloned viral DNA lacking both copies of the 115-nucleotide sequence is capable of directing the transcription of viral RNA posttransfection. This viral RNA is polyadenylated, spliced, exported from the nucleus, and translated into protein normally. However, virions isolated from the culture medium 48 h posttransfection lack viral RNA. When mutant DNA is contransfected with wild-type DNA, the virions produced 48 h later contain wild-type RNA but not mutant RNA, even though both RNAs are present in the cytoplasm. We propose that the 115-nucleotide element of Rous sarcoma-avian leukosis virus encodes a cis-acting sequence that is necessary for the proper incorporation of viral RNA into virions.

Animals↗
PubMed1982

Polypurine tract adjacent to the U3 region of the Rous sarcoma virus genome provides a cis-acting function.

The v-src coding region was deleted from cloned Rous sarcoma virus DNA, and the deleted clones were tested for infectivity by transfection. All of the coding region, as well as most of the sequences lying between v-src and the unique 3' region (U3), could be deleted without affecting viability. However, at least 9 and at most 29 of the nucleotides in the purine-rich tract adjacent to U3 were necessary for growth, even in the presence of a helper virus. It is concluded that these nucleotides (the polypurine tract) provide a cis-acting function necessary for retrovirus replication.

Animals↗
PubMed1982

Optical measurements of oxygen delivery and consumption in gerbil cerebral cortex.

Oxygen metabolism of the cerebral cortex of anesthetized gerbils was monitored by surface fluorescence and reflectance spectrophotometry both in vivo and in specimens freeze-trapped by the surface-freezing technique. Fiber optic light guides were used for optical coupling for determining mitochondrial flavoprotein and pyridine nucleotide fluorescence and for recording dual-wavelength reflectance spectra that indicated the levels of ferrocytochromes aa3 and c + c1 in the cortex and the oxygen saturation of cortical hemoglobin. During anoxic episodes increases in ferrocytochromes aa3 and c + c1 and in reduced pyridine nucleotides and flavoproteins were observed only when the cortical hemoglobin was more than 85% disoxygenated. Indeed the steady-state levels of oxidation-reduction of mitochondrial respiratory-chain components remained constant over a wide range of oxygen delivery, increased reduction being observed only when the fraction of inspired oxygen fell below 6%; these properties of mitochondria in vivo resemble those found in vitro. However, in normoxic animals the absorbance at 605 nm that may arise from ferri- or ferrocytochrome aa3 is larger than would be expected of purified mitochondria and may represent a pool of mitochondria that remains reduced at all levels of tissue oxygenation or a pigment not involved in oxygen metabolism.

Animals↗
PubMed1982

Splicing of intervening sequences introduced into an infectious retroviral vector.

The v-src gene was removed from Rous sarcoma virus DNA and replaced with either a cDNA or genomic clone of human alpha-chorionic gonadotropin. Transfection of the recombinant retrovirus genomes into normal chicken fibroblasts produced nontransforming recombinant virus in high titer. Neither helper virus nor selective conditions were needed. Cells infected with the recombinant viruses expressed RNA containing the gonadotropin sequences in levels equivalent to those of term human placenta (approximately 0.5% of poly A+). Essentially every fibroblast in the culture was infected; the infected cells contained approximately one recombinant provirus each. The gonadotropin intervening sequences were removed precisely from the recombinant genomes that contained them, creating recombinants carrying a perfect cDNA copy of the original genomic insert. However, the intervening sequences were removed inefficiently such that several viral replicative cycles were necessary before all genomes had been processed completely. The implications of these observations to the transduction of viral oncogenes and the creation of processed pseudogenes are discussed.

Animals↗
PubMed1978

Heterogeneity of oxygen delivery in normoxic and hypoxic states: a fluorometer study.

An on-line, real-time histogram display of heterogeneity of oxygen delivery to perfused and in situ organs is afforded by a flying-spot fluorometer that provides excitation for either oxidized flavoprotein of the mitochondrial space or reduced pyridine nucleotide of mitochondrial and cytosolic spaces. Emission from the two fluorochromes is acquired at 10(4) to 10(5) data points/s and histograms of the fluorescence intensity versus the number of occurrences of that intensity are displayed at 1--10 times per second. The histograms show alterations of the intensity and of the degree of heterogeneity of the redox states of perfused heart with model coronary occlusion, of perfused and in situ rat liver, and of rat and gerbil models of stroke. The percentage change of oxygen delivery to the intracellular space can be calculated from the areas under the histogram.

Brain↗
PubMedDate not supplied

[Use of strong opioids in the treatment of cancer pain in adults and children].

A high percentage of adults and children with advanced cancer suffer from pain. Strong opioids for pain control, e.g. morphine, slow-released morphine or buprenorphine, should be administered early according to the intensity of pain. The analgesics should be given orally whenever possible. They must be given at fixed intervals based on the duration of their action. The dose must be titrated to the needs of the patient. Sometimes more than 1000 mg morphine orally per day is necessary. Correctly used strong opioids produce only a few side-effects, especially constipation and vomiting. Many studies in adult cancer patients all over the world demonstrate the effectiveness of strong opioids for pain control. Children should be treated in the same way and comparable data in children with cancer pain must be collected.

Administration, Oral↗