[A list of social support gaining tactics].

Two studies were conducted to compile a list of social support gaining tactics. Support of three types (tangible, mental, and informational) from four sources (parents, professors, close friends/boy girl-friends/siblings, and friends) was considered. In Study 1, 25 Taiwanese college students were interviewed, and 151 students filled out an open-ended questionnaire. They were asked, for each type and source, to list the kinds of tactics they had used or they would use when they needed social support, and 33 items were collected. In Study 2, factor analysis found seven factors for them: passionate appeal, entreaty, roundabout appeal, other exploitation, reward, reason appeal, and threat.

Stress and social support in mental and physical health of Chinese students in Japan.

This study examined the influence of stress and social support on mental and physical health and happiness of 175 Chinese students enrolled in 13 Japanese universities. Needed support accounted for only 10% of the variance in reported stress, indicating that the relation between the two variables was not strong and they were generally independent. With greater scores on stress or needed support and lower scores on perceived or received support, depression and somatic complaints become more severe. The higher the scores on perceived or received support, the higher the reported happiness. Both perceived and received support showed a buffering effect on somatic complaints. Finally, stress and needed support had an interesting interaction, indicating that only among students reporting more stress did students who experienced greater need for support report more severe depression than those who experienced less need for support.

The causes and influence of transitional stress among Chinese students in Japan.

The structure, characteristics, and influence of stressors among Chinese students in Japan were examined. One hundred seventy-five Chinese students completed questionnaires that included stressor items from Holmes and Rahe (1967) and Yo and Matsubara (1990) and mental-physical health items that assessed depression, somatic complaints, and happiness. Stressors among Chinese students in Japan were classified as 5 factors: Interpersonal Problems, Academic Problems, Health/Living Problems, Financial Anxiety, and Environmental Problems. These 5 factors accounted for 35%, 18%, and 4%, respectively, of the variance in depression, somatic complaints, and happiness. Thus, the factors were clearly detrimental to mental health but had a limited influence on physical health and happiness.

Comparison of differences in the association of social support and adjustment between Chinese and Japanese students in Japan: a research note.

This study examined the associations of Japanese students' social support, and their adjustment in comparison with those of Chinese students. Needed and actual support and the discrepancy between the two were examined, and Japanese professors and other Japanese students were employed as major sources of support. Respondents were 68 Japanese and 64 Chinese students in Japan. Analyses indicated that, although there was no significant difference between Japanese and Chinese students' adjustment, the associations of social support and adjustment were different between the two groups. This study also documented that Japanese professors were important as a source of support for Chinese students more than they were for Japanese students and that the support needed from other Japanese students correlated negatively with the adjustment of Chinese students.

[The effects of social support reciprocity on mental and physical health of young adults].

The present study examined the effects that reciprocity of social support has on mental and physical health of young adults from the viewpoint that an individual is both an active and passive support provider as well as receiver. The questionnaire, completed by 505 young adults, included items that measured four kinds of support: requested by and provided to others, and requested and received by them. It also asked about the affects associated with support relationships, in addition to the level of adjustment and mental and physical health. Correlational analyses showed that young adults felt their support relationships were fairly reciprocal. ANOVA and multiple regression indicated that lack of reciprocity was in general associated with negative affects and poor health. Providing more support than receiving lead to dissatisfaction, and receiving more than providing to a feeling of indebtedness. Finally, the data supported the prediction that there was a path from support equity to affective state to mental and physical health.

Cross-cultural adjustment of Chinese students in Japan.

The present study examined responses of 92 Chinese students in Japan to questionnaires which included adjustment items selected from work of Baker in 1981 and Uehara in 1988. These items were classified by factor analysis into four scales of Emotional, Academic, Cultural-Social, and Environmental. Adjustment scores on the Environmental scale were higher than those on the other three scales. Country of origin was a significant influence only for scores on the Environmental scale. Students who came from Taiwan scored higher on adjustment. There were gender differences on Emotional and Academic scales; male students reported higher adjustment. The effects of students' length of residence and proficiency in the Japanese language could be seen in scores on Academic and Cultural-Social scales; the students who had a longer period of stay or had higher proficiency in Japanese language had higher scores on adjustment. Thus, results indicated that personal differences were reflected in subfactors of adjustment.

[A examination of a causal model for received support and adjustment of Chinese students in Japan].

The present study examined the effect of received support on adjustment by foreign students, with data from 33 Chinese students who completed questionnaires at three occasions: three months (the first period), nine months (the second period), and one year and nine months (the third period) after they arrived in Japan. The Social Support Scale for Chinese Students in Japan (Jou, 1993a) and items for measurement of adjustment were used in the questionnaires. Analysis of Variance results revealed no differences among the amounts of support received during the three periods, but compared with the first or second, adjustment was better during the third period. Results from path analysis indicated that support in the first period was positively related to adjustment in the first period, the first period adjustment and second period support positively to the second period adjustment, and only the second period adjustment positively to the third period adjustment. Thus, the present study suggests that it is especially necessary to provide more support to foreign students during the critical early period in order to facilitate their adjustment.

Immunospecific targeting of cytosine arabinonucleoside-containing liposomes to the idiotype on the surface of a murine B-cell tumor in vitro and in vivo.

A new tumor model is described that is suitable for the evaluation of antibody-directed drug-delivery protocols and a modification in the procedure for covalently coupling antibody to the surface of drug-containing liposomes is presented. These immunospecific liposomes containing cytosine arabinonucleoside (Ara-C) have been tested in vitro and in vivo for their ability to kill a B-cell tumor. The target of the immunospecific-Ara-C liposomes is the idiotype associated with an antigen-specific immunoglobulin receptor on the cell surface of a murine B-cell hybrid (2C3). Affinity-purified antibodies specific for the idiotype were covalently coupled to modified lipid on the surface of the large unilamelar liposomes containing drug. These liposomes were shown to kill idiotype-positive 2C3 cells in vitro, but not idiotype-negative variants of this same cell line. It was also established in vitro that the drug-containing liposomes were at least 40 times more efficient than free Ara-C in the killing of the tumor cells. The 2C3 tumor was also propagated in vivo following the i.p. administration of tumor cells. The tumor grew initially as multiple foci within the peritoneum and subsequently spread to the spleen. Tumor-bearing mice were treated either with free Ara-C or with immunospecific liposomes containing Ara-C. Tumor growth in the primary tumor nodules and in the spleen was monitored by the administration of bromodeoxyuridine to the tumor-bearing animals followed by the immunofluorescent staining of cells with a monoclonal anti-bromodeoxyuridine antibody to estimate the proportion of cells in S phase. Our data from five out of seven animal experiments shows that the immunospecific-Ara-C liposomes, but not free drug, reduced tumor growth in the spleen. However, neither the liposomes containing drug nor the free drug were able to alter the growth of the primary tumor nodules growing in the peritoneal cavity. These results suggest that immunospecific-Ara-C containing liposomes may be useful in conjunction with other cytoreductive protocols in controlling tumor growth or preventing the spread of the tumor to other sites, but that immunospecific-Ara-C containing liposomes by themselves are not likely to eliminate an established tumor in vivo. We also demonstrate here that the administration of immunospecific-Ara-C containing liposomes in an animal having high levels of circulating tumor-associated antigen (i.e., IgG containing the idiotype) represents a potential clinically relevant hazard which must be considered when designing antibody-directed drug-delivery protocols.

Monoclonal antibodies specific for two different histological types of human lung carcinoma.

Hybridomas secreting monoclonal antibodies specific for human lung cancer were produced by fusing immunized mouse spleen cells with mouse myeloma line X63-Ag8.653. Prior to fusion, BALB/c mice were immunized with two different histological types of human lung cancer (Squamous cell carcinoma and adenocarcinoma) obtained from surgery. An immunocytoadherence test was used to select hybridomas secreting antibodies that bound the patient's lung tumor, but did not bind to a B-lymphoblastoid cell line derived from the same patient. Five stable antibody-producing hybrids have been established and cloned. The antibodies produced by these clones have been characterized according to their light and heavy chain isotypes and for their specificity. In addition to binding to the tumor used for immunization, the antibodies bound to other lung tumors of the same histological type (i.e., squamous cell or adenocarcinoma). This reactivity was observed with both established lung tumor cell lines and with fresh tumors obtained from biopsy of patients in our clinic. Some significant reactivity was also observed with large cell carcinoma but the antibodies did not react with small cell carcinomas of the lung, bronchiolo-alveolar cell carcinoma, cancer of the esophagus and stomach, melanomas, several types of leukemias, normal human lung tissue, fibroblasts, or erythrocytes of type A, B, or O. Two of the five antibodies, 5C7 and 5E8 cross-reacted with one breast cancer obtained from surgery, and 5C7 also cross-reacted with one melanoma biopsy specimen. These results suggest that we have generated monoclonal antibodies that recognize a set of antigenic determinants that are commonly expressed on a portion of human lung tumors that are not detectable on a variety of other human tumors or normal human tissue.

A filtration double antibody radioimmunoassay that simplifies and semi-automates the isolation of immune precipitates.

A semi-automation of fluid phase double antibody radioimmunoassay has been developed. The immune precipitate that was formed in 96-well microtitration plates was harvested and washed on microfibre filters using a Titertek cell harvester. A disc transfer system originally designed for use with the harvester was used as a quick and easy method of transferring the filter discs containing immune precipitate into vials for counting. The results of radioimmunoassay using the microtitration plate-filtration and conventional tube-centrifugation method are essentially identical. The microtitration plate-filtration radioimmunoassay has the following advantages over the conventional tube-centrifugation method: (1) there is no centrifugation required; (2) handling of microtitration plate is easier than the tubes in racks; and (3) it requires much less time to perform the assay.

Chemical nature of mouse antibodies homologous to the 3-pyridylazo group: the fine specificities of hybridoma and serum antibodies.

Rabbit antibodies which bind aromatic annular nitrogen-containing haptens exhibit a specificity wherein such nitrogens are distinguished from the closely related aromatic CH group. The mouse hybridoma system was used to extend this work producing hybridoma antibodies homologous to the 3-pyridylazo group. Fine specificity mapping by double antibody radioimmunoassay revealed differences among the individual hybridomas, as well as a greater resemblance of mouse serum antibodies to rabbit serum antibodies than to hybridoma antibodies. Quantitative structure-activity relationships applying the parameters of hapten molar refractivity had hydrophobicity were used to help elucidate the types of intermolecular forces involved in the interaction of pyridine derivatives with the antibodies. The results are consistent with the interpretation that pyridine binding to antibody does not involve desolvation.

Alternative-substrate inhibition and the kinetic mechanism of the beta-galactoside/proton symport of Escherichia coli.

The effects of competing alternative substrates on the rate of uptake by galactoside/proton symport were investigated. These experiments produced a decrease in apparent maximum velocity with increased alternative-substrate concentration that cannot be accounted for by a simple ordered mechanism. This, together with non-linearities in the variation of the apparent kinetic constants with alternative-substrate concentration, can be accounted for by a random mechanism for galactoside and proton binding.

Monoclonal antibodies and a heterobifunctional reagent: a novel approach to the vectorial labeling of selected membrane proteins.

Many applications exist and others are envisioned for the chemical coupling of macromolecules to membrane proteins on the surface of mammalian cells. The ability to use antibody as a means to label and subsequently to follow the distribution of cell surface proteins is reported here. A new procedure is outlined for covalently coupling monoclonal antibodies to thiol-containing membrane proteins. The key reagent in the coupling reaction is the commercially available heterobifunctional reagent N-succinimidyl 3-(2-pyridyldithio)propionate (SPDP). The coupling proceeds in a simple two-step reaction in aqueous medium under very mild conditions. This results in a very efficient and stable attachment of anti-hapten antibodies to a selected set of cell surface proteins without any loss in cell viability and without denaturing the antibody molecule. The hapten-binding activity of the antibody is exploited to monitor the re-distribution of the antibody-labeled cell surface proteins periodically after the coupling reaction. The hapten binding activity can also be utilized to isolate membrane macromolecules via affinity chromatography.

Immunochemical characterization of prostatic acid phosphatase with monoclonal antibodies.

Hybridoma-derived monoclonal antibodies to human PAP have been produced by fusion of mouse myeloma cells [P3 x 63 Ag 8.653] with spleen cells from mice immunized with purified PAP. One hundred fifty-six out of 252 clones were found to produce antibodies against PAP. These monoclonal antibodies were classified into four different subclasses as IgM [3 clones], IgG2a [2 clones], IgG3 [1 clone], and IgG1 (150 clones] with k-chains. Four monoclonal antibodies, IgG1, IgG2 a, IgG3, and IgM, were selected from the 156 hybridoma clones for immunologic characterization. Results from a binding assay suggested that monoclonal anti-PAP antibodies IgG1 and IgM recognized two distinct antigenic determinants of the PAP molecule, while the hybridoma IgG2a and IgG3 antibodies recognized another antigenic determinant. The specificity of these four hybridoma anti-PAP antibodies has been evaluated by the immunohistochemical method and competitive-binding assay. Monoclonal antibodies IgG2a and IgG3 as well as polyclonal xenoantibodies were found to react with PAP as well as with nonprostatic acid phosphatases; and antibodies IgG1 and IgM reacted more specifically with PAP. These results indicated that monoclonal anti-PAP antibodies IgG1 and IgM possessed a higher specificity for human PAP in comparison with monoclonal antibodies IgG2a, IgG3, and xenoantibodies. The monoclonal anti-PAP IgG1 and IgM antibodies may be useful in delineating antigenic structure of the PAP molecule, as well as in the refinement of serologic determination and immunocytochemical study of PAP in human prostate cancer.

Coupling of protein antigens to erythrocytes through disulfide bond formation: preparation of stable and sensitive target cells for immune hemolysis.

An efficient technique has been developed for coupling protein antigens to erythrocyte membranes. The procedure involves three steps. First, 3-(2-pyridyldithio)propionyl residues are introduced into the protein by reaction with a heterobifunctional reagent, N-succinimidyl 3-(pyridyldithio) propionate. Second, the addition of disulfide groups to sheep erythrocytes (SRBC) is achieved by coupling dithiodiglycolic acid to SRBC with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. The disulfide bonds of the dithiodiglycolyl-SRBC conjugate are then reduced with dithiothreitol. Finally, the 3-(2-pyridyldithio)propionyl-protein conjugate is covalently coupled to the thiolated SRBC through thiol/disulfide exchange to form the disulfide-linked antigen-SRBC conjugate. The procedure requires only 10-500 microgram of protein antigen for the preparation of 50 microliter of packed protein-coupled SRBC. Antibodies binding to antigen on the erythrocyte initiate a complement-dependent immune lysis of the target cells. Target cells prepared by this method are stable for at least 4 wk at 4 degrees C in phosphate buffer (pH 7.2) and are capable of detecting as little as 40 pg of antibody in a hemolytic assay without noticeable nonspecific lysis.

Succinylation of hapten-protein conjugates facilitates coupling to erythrocytes by water soluble carbodiimide: preparation of stable and sensitive target cells for use in hemolytic assays.

A facile method is described for the preparation of haptenated sheep red blood cells (SRBC) for use as targets in hemolytic spot and plaque assays for the detection of anti-hapten antibody. The method involves the use of the water soluble 1-ethyl-3-(3-dimethyl-aminopropyl)carbodiimide (EDCI) as a reagent to couple hapten-succinyl-rabbit serum albumin conjugates to SRBC. The presence of the succinyl groups on such conjugates is shown to increase the efficacy of the resulting target cells, presumably by acting as a substrate for the EDCI and thus increasing the extent of coupling to SRBC.