Functional independence of the epidermal growth factor receptor from a domain required for ligand-induced internalization and calcium regulation

We have located the distal boundary of the tyrosine kinase domain of the EGF receptor and have identified a distinct sequence in the C' terminus required for EGF-dependent receptor internalization, leading to receptor down-regulation and degradation. Within this receptor domain, an 18 amino acid highly negatively charged region of predicted helical structure is required both for endocytosis via a high-affinity, saturable pathway and for ligand-stimulated increases in cytosolic calcium. In contrast to kinase-inactive, internalization-competent receptors, kinase-active, internalization-defective receptors effectively signaled gene transcription, morphological transformation, and growth. These observations support the hypothesis that mitogenic responses to EGF are mediated by activation of the intrinsic protein tyrosine kinase activity of the membrane-bound receptor, with ligand-induced internalization serving to terminate the signal.

[Experience in using modified HM-3 Dornier lithotripter to treat urinary tract stones]

Low pressure generator has been developed mainly to reduce pain and kidney injury while at the same time maintain an equally effective stone-free rate. Our experience in using Modified HM-3 Dornier lithotripter to treat urinary tract stones has given an average of stone-free rate (58.88%) quite similar to what the conventional one can give. Compared with the conventional intervention, the modified one might increase by 52.07% (2281 vs 1500 pulses) in the average frequency of shock wave and by 26.52% (38.40 vs 30.35 minutes) in average operation time. However, low pressure may contribute to less complications and overall smoother procedure under oral analgesic use.

Identification and expression of a human cytomegalovirus early glycoprotein

A human cytomegalovirus early gene which possesses three temporally regulated promoters is located in the large unique component of the viral genome between 0.054 and 0.064 map units (C.-P. Chang, C.L. Malone, and M.F. Stinski, J. Virol. 63:281-290, 1989). This gene contains a major open reading frame (ORF) located 233 bases downstream of the cap site of an early unspliced RNA. The major ORF predicts a polypeptide of 17 kilodaltons (kDa) which contains a glycoproteinlike signal and anchor domains as well as potential N-glycosylation sites. Antisera were prepared against synthetic peptides derived from amino acid sequences within the major ORF. The antisera detected a viral glycoprotein of 48 kDa in infected cells and recognized the in vitro-translated 17-kDa protein early-gene product. The viral glycoprotein, designated gp48, was modified by N-linked glycans and possibly O-linked glycans. The synthesis of gp48 occurred in the absence of viral DNA replication but accumulated to the highest levels at late times after infection. Since gp48 was found in the virion, it is considered an early structural glycoprotein.

A human cytomegalovirus early gene has three inducible promoters that are regulated differentially at various times after infection

The long inverted repeat and the adjacent sequences are major early transcription sites of the human cytomegalovirus genome (M. W. Wathen and M. F. Stinski, J. Virol. 41:462-477, 1982). An early transcription unit which flanks the large terminal repeat was analyzed by RNA mapping at various times after infection. Three unspliced, overlapping RNAs were transcribed from different initiation sites and terminated at the same 3' end. Individual promoters were isolated for all three transcripts. These promoters were activated in trans by viral immediate-early (IE) regulatory proteins after either infection with virus or cotransfection with IE2 alone or IE1 plus IE2 genes. DNA sequence analysis detected TATA and CAAT boxes plus multiple-dyad symmetries in the promoter-regulatory region. Deletion analyses showed that the maximum inducible promoter activity lay in a 230-base-pair region. When in the viral genome, the three promoters were regulated differentially during the course of infection. The upstream promoter was used only at late times after infection. Possible reasons for viral RNAs with multiple 5' ends at different times after infection and the recognition of the upstream promoter at only late times after infection are discussed.

Secretion of functional antibody and Fab fragment from yeast cells

We have constructed yeast strains that secrete functional mouse-human chimeric antibody and its Fab fragment into the culture medium. For chimeric whole antibody, cDNA copies of the chimeric light-chain and heavy-chain genes of an anti-tumor antibody were inserted into vectors containing the yeast phosphoglycerate kinase promoter, invertase signal sequence, and phosphoglycerate kinase polyadenylylation signal. Simultaneous expression of these genes in yeast resulted in secretion of properly folded and assembled chimeric antibody that bound to target cancer cells. Yeast chimeric antibody exhibited antibody-dependent cellular cytotoxicity activity but not complement-dependent cytotoxicity activity. For production of Fab fragments, a truncated heavy-chain (Fd) gene was created by introducing a stop codon near the codon for the amino acid at which papain digestion occurs. Simultaneous expression of the resulting chimeric Fd and light-chain genes in yeast resulted in secretion of properly folded and assembled Fab fragment that bound to target cancer cells.

Cockroach hypersensitivity: preliminary study of allergic cockroach asthma in Taiwan

One hundred eight-two atopic patients were skin tested with cockroach antigen. Of these 182 patients, 54.9% gave positive immediate skin reaction by intracutaneous test. Among those atopic patients tested, 57.5% of patients with asthma and 50.7% of patients with allergic rhinitis were sensitive to cockroach extracts. The specific IgE antibody was determined by fluoroallergosorbent test. Of 79 cockroach-positive atopic patients, 39.2% were found to contain IgE antibodies against cockroach. No specific IgE was detected in cockroach-negative atopic and nonatopic subjects. Bronchial provocation test with cockroach antigen was performed on 15 subjects. Immediate asthmatic response was detected in six of nine cockroach-positive subjects with asthma. Two cockroach-negative subjects with asthma and four nonatopic subjects demonstrated no significant decrease in FEV1. The results indicate that cockroach induces antigen-specific IgE-mediated bronchial asthma, and cockroach is one of the major causes of allergic asthma.

Human stomach alcohol and aldehyde dehydrogenases (ALDH): a genetic model proposed for ALDH III isozymes

Isozyme phenotypes of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) from human gastroendoscopic as well as surgical gastric biopsies were determined by starch gel electrophoresis and agarose isoelectric focusing. gamma gamma ADH isozymes were expressed predominantly in the mucosal layer of the stomach, whereas beta beta isozymes were in the muscular layer. In the 56 gastroendoscopic mucosal biopsies examined, the homozygous ADH3 1-1 phenotype was found in 75% of the samples, and the heterozygous ADH3 2-1 phenotype in 25%. Accordingly, the gene frequencies of the alleles ADH1/3 and ADH2/3 were calculated to be 0.88 and 0.12, respectively. Using a modified agarose isoelectric focusing procedure, gastric ALDH I, ALDH II, and up to five ALDH III forms could be clearly resolved. The ALDH III isozymes accounted for more than 80% of the total ALDH activities in gastric mucosa and exhibited Km values in the millimolar range for propionaldehyde at pH 9.0. Forty-five percent of the 55 gastroendoscopic biopsies studied lacked ALDH I isozyme. The complex gastric ALDH III isozyme phenotypes seen in these biopsies fall into three patterns. They can be interpreted by a genetic hypothesis, based on a dimeric molecule, in which there are two separate genes, ALDH3a and ALDH3b, with the ALDH3b locus exhibiting polymorphism. The homozygous phenotypes ALDH3b 1-1 and ALDH3b 2-2 were found to be 4 and 76%, respectively, and the heterozygous ALDH3b 2-1 phenotype 20%, of the total. Therefore, the allele frequencies for ALDH1/3b and ALDH2/3b were calculated to be 0.14 and 0.86, respectively. Several lines of biochemical evidence consistent with this genetic model are discussed.

Escherichia coli secretion of an active chimeric antibody fragment

A chimeric mouse-human Fab protein that binds specifically to the human carcinoma cell line C3347 has been expressed and secreted from Escherichia coli. This molecule, which contains functionally assembled kappa and Fd proteins, binds as effectively to sites on the surface of C3347 cells as Fab fragments prepared proteolytically from whole chimeric or mouse antibody. The production in Escherichia coli of foreign heterodimeric protein reagents, such as Fab, should prove useful in the management of human disease.

Liver alcohol and aldehyde dehydrogenase isoenzymes in Chinese

Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) isoenzyme phenotypes were determined in 71 autopsy liver specimens by agarose isoelectric focusing and starch gel electrophoresis, respectively. Ninety percent of the livers examined exhibited a pH-optimum for ethanol oxidation at pH 8.5, instead of 10.5 which is usual among Caucasians. The homozygous ADH2 2-2 phenotype was found to be 59%, and the heterozygous ADH2 2-1 phenotype, 31%. The remaining 10% of the livers, exhibiting a pH-optimum at 10.5, were homozygous ADH2 1-1 phenotype. Accordingly, the gene frequencies of the alleles ADH2(2) and ADH2(1) were calculated to be 0.75 and 0.25, respectively. Fifty-eight percent of the 71 livers examined possessed both the activities of ALDH I and ALDH II isoenzymes, whereas 42% lacked the ALDH I activity. The implications of these distributions of liver ADH and ALDH isoenzyme patterns among Orientals for ethanol elimination, alcohol sensitivity and alcoholism are discussed.

Chimeric mouse-human IgG1 antibody that can mediate lysis of cancer cells

A chimeric mouse-human antibody has been created that recognizes an antigen found on the surface of cells from many carcinomas. Immunoglobulin constant (C) domains of the mouse monoclonal antibody L6, C gamma 2a and C kappa, were substituted by the human C gamma 1 and C kappa by recombining cDNA modules encoding variable or C domains. The cDNA constructs were transfected into lymphoid cells for antibody production. The chimeric antibody and mouse L6 antibody bound to carcinoma cells with equal affinity and mediated complement-dependent cytolysis. In the presence of human effector cells, the chimeric antibody gave antibody-dependent cellular cytotoxicity at 100 times lower concentration than that needed for the mouse L6 antibody. The chimeric antibody, but not the mouse L6 antibody, is effective against a melanoma line expressing small amounts of the L6 antigen. The findings point to the usefulness of the chimeric antibody approach for obtaining agents with strong antitumor activity for possible therapeutic use in man.

Synthesis, evaluation of chemical reactivity, and murine antineoplastic activity of 2-hydroxy-5-(3,4-dichlorophenyl)-6,7-bis(hydroxymethyl)-2,3-dihydro-1H- pyrrolizine bis(2-propylcarbamate) and 2-acyloxy derivatives as potential water-soluble prodrugs

2-Hydroxy-5-(3,4-dichlorophenyl)-6,7-bis(hydroxymethyl)-2,3-dihydro-1H- pyrrolizine bis(2-propylcarbamate) (11) was prepared in a multistep synthesis. The 2-hydroxy group was used to prepare ester prodrugs 14 and 15, and the antineoplastic activities of 11, 14, and 15a were compared to 1 (the 2-deoxy analogue of 11) in murine P388 lymphocytic leukemia and B16 melanocarcinoma. The alcohol 11 showed comparable activity to 1, while 14 was less active and 15a showed very low activity. The hydrolytic rates of 1, 11, 14, 15a, and 15b were compared, and it was found that the two carbamate moieties were much more susceptible toward hydrolysis than the C-2 esters. The salts 15a and 15b exhibited good water solubility, 3.0 X 10(-2) and 3.88 X 10(-2) M, respectively.

Identification of 2-keto-4-methylthiobutyrate as an intermediate compound in methionine synthesis from 5'-methylthioadenosine

The synthesis of methionine from 5'-methylthioadenosine was examined in vitro using cell-free homogenates of rat liver. We had previously reported that methionine synthesized by this system contained carbons from the ribose moiety of 5'-methylthioadenosine (Backlund, P. S., Jr., and Smith, R. A. (1981) J. Biol. Chem. 256, 1533-1535). The present study examines some of the steps involved in this conversion. 2-Keto-4-methylthiobutyrate was identified as one of the products of 5'-[methyl]14C]methylthioadenosine when incubated in vitro with rat liver homogenates. Partial purification of the enzyme system by gel exclusion chromatography to remove small molecular weight substrates and cofactors revealed that synthesis of 2-keto-4-methylthiobutyrate requires magnesium and is inhibited by calcium. 5-Methylthioribose 1-phosphate can replace 5'-methylthioadenosine as a substrate for methionine synthesis under these conditions, but 5-methylthioribose cannot. 5-Methylthioribonic acid was prepared and was found not to be an intermediate compound in this pathway. The final step in this pathway for methionine synthesis is then the transamination of the keto acid, catalyzed by glutamine and asparagine transaminases.

Vinylogous carbinolamine tumor inhibitors. 8. Activity of bis(acyloxymethyl) derivatives of pyrroles and pyrrolizines against a panel of murine leukemias and solid tumors

The activity of three pyrroles and four pyrrolizines is compared in several different experimental leukemias and solid tumors in mice. Two compounds were particularly noteworthy, the bis(N-cyclohexylcarbamate) and the bis[N-(2-propyl)] derivatives of 2,3-dihydro-5-(3,4-dichlorophenyl)-6,7-bis(hydroxymethyl)-1H-pyrrolizine. These two compounds showed a very high level of activity against B16 melanocarcinoma, CD8F1 mammary tumor, colon tumor 26, and colon tumor 38, and a significant number of "cures" were recorded. The isopropyl compound was more potent than the cyclohexyl compound, but both showed a similar profile of activity.

Studies on the progress of occupational cervicobrachial disorder by analysing the subjective symptoms of work-women in assembly lines of a cigarette factory

The Committee on Cervicobrachial Syndrome in Japan Association of Industrial Health (JAIH) made a report on the questionnaires for checking for the complaints of patients suffering from Occupational Cervicobrachial Disorder (OCD). In order to reveal how the complaints develop in the progress of OCD, we analysed the complaints of 117 workwomen in assembly lines of a cigarette factory by using the questionnaires. And the followings were made clear: 1) At the mild stage of OCD, stiffness or dullness at the neck and shoulders, and eyestrain become remarkable. 2) At the moderate stage, pain at the neck, shoulders, arms and hands, dullness at extremities, general fatigue, pain or heavy feeling in the head, increased irritability etc. become remarkable in addition to the mild stage complaints. 3) At the severe stage, pain and dullness at the back, numbness at arms and hands, hand coldness, sleep disturbance etc. become remarkable in addition to the moderate stage complaints. 4) Various sufferings in daily life such as "I want to lie down at rest time," "I lack patience to go on reading long," "It is hard for me to go on writing long," and "Fixed sitting soon tires me" become more and more frequent as the stage advances. We consider it is important in the diagnosis of OCD to pay attention to the general symptoms such as general fatigue, pain or heavy feeling in the head, increased irritability and sleep disturbance, together with complaints at the neck, shoulders, arms and hands.

A surveillance of human influenza virus in swine in southern Taiwan

From September 1970 to December 1971, samples were taken monthly from farm pigs, piglets and abattoir pigs in Southern Taiwan for virus isolations and serologic studies. A total of 10 strains of hemagglutinating agent were isolated in January and July 1971, following 2 epidemics of human influenza occurring in December 1970 and June 1971, respectively. Three strains were antigenically confirmed as influenza A similar to A/Hong Kong/68 virus.

Cold water immersion test in patients with vibration disease

Peripheral vascular disorder is one of the most important symptoms in diagnosing vibration disease. Several kinds of tests have been introduced to evaluate the peripheral vascular function. Among those tests, cold water immersion test has been mostly applied. In Japan, the generally used method is to measure the skin temperature of one finger of the hand immersed up to the wrist joint in water at 5 degreesC for 10 minutes. However, because the suffering during the test is so severe and some unfavorable warning symptoms have been observed during group examinations, a safer and milder method is more desirable. In order to examine the applicability of the test by using water at 10 degreesC in comparison with that at 5 degreesC, and to know the degree of suffering during the tests, a comparative study was performed. Sixteen students and 29 patients with vibration disease joined in this study. The results suggest that water at 10 degreesC can be effective stimulus, if the immediate rewarming response is used for evaluation. The self-rating scores revealed that the suffering was milder in case of water of 10 degreesC than at 5 degreesC for both the students and the patients. And the patients seemed to suffer more from chest discomfort than the students.

Enterotoxigenicity and invasive capacity of "enteropathogenic" serotypes of Escherichia coli

Forty-two strains of Escherichia coli that agglutinated in pools of antisera used to identify "enteropathogenic" serotypes were tested for heat-labile and heat-stable toxin production and for their ability to invade intestinal mucosa. None of the strains tested were enterotoxigenic or enteroinvasive as determined by the adrenal cell (heat-labile toxin), the suckling mouse (heat-stable toxin), or guinea pig eye (invasive capacity) assays. Our observations suggest that serotyping of E. coli is an unreliable method to identify isolates that are capable of causing gastroenteritis, at least as determined by available in vitro techniques.

Influenza virus isolations from dogs during a human epidemic in Taiwan

During an islandwide outbreak of human influenza in June and July 1971, throat swabs were taken from dogs and cats in 3 urban communities of Taiwan. Eight influenza isolates were obtained from dogs in July 1971: two were identified as influenza A closely related to the human Hong Kong/68 virus, and one was a strain of influenza type B closely resembling human influenza B virus. The latter is the first such reported isolation from dogs under natural conditions.

Renal adenocarcinoma in an owl monkey (Aotus trivirgatus)

A renal adenocarcinoma in the right kidney of a 5-year-old female owl monkey is reported.