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We performed the modified-embedded-atom-method (MEAM) based molecular dynamics (MD) simulations to investigate the plastic deformation and phase transformation behaviors in the CoCrFeMnNi HEA under high compression at room temperature. Our MD simulations revealed that the stress-induced phase transformations in the CoCrFeMnNi HEA are strongly crystal orientation-dependent. The [0 0 1] uniaxial compression can induce the significant face-centered-cubic (fcc) -to-hexagonal-close-packed (hcp) phase transformation via successive emissions of partial dislocations from the extended stacking faults, twin boundaries and hcp-lamellas created during the early stage of deformation. As for the [1 1 0] and [1 1 1] uniaxial compressions, however, the transformed hcp atoms can simply form the intrinsic/extrinsic stacking faults. Although the [0 0 1] uniaxial compression produced a much lower dislocation density than the other two systems, it induced much more constituents transformed into the hcp atoms at the end of phase transformation. Our results clearly indicated that the deformation twin boundaries and extended hcp-lamellas play a critical role in facilitating the stress-induced fcc-to-hcp phase transformation in the CoCrFeMnNi HEA. Furthermore, it was found that the phase transformation in the CoCrFeMnNi HEA can be effectively facilitated by a large deviatoric compressive stress while it may tend to be significantly retarded by a hydrostatic compression. Our results also showed that the plastic deformation behaviors in Ni under high compression are very similar to those occurred in the CoCrFeMnNi HEA though nearly all the hcp atoms can simply constitute the intrinsic/extrinsic stacking faults without the formation of any bulk hcp phase in the fcc lattice. The main discrepancy in the phase transformation behaviors between the Ni and CoCrFeMnNi HEA can be largely attributed to the much lower stacking fault energy of the CoCrFeMnNi HEA than other fcc metals.

The superior mechanical properties of high-entropy alloys (HEAs) have made an outstanding success in materials science and engineering. Studies to date have been devoted to what the severe lattice distortion induces. However, most researchers focus on its stimulation to plastic deformation instead of scrutinizing the variations on elasticity. Compared with conventional alloys, HEAs may perform disproportionate elasticity with uneven local lattice strain resulting from the severe lattice distortion. Therefore, it is necessary to survey its influence on the mechanical properties of HEAs systematically. In this study, the Lennard-Jones (LJ) potential, the embedded atom method (EAM) potential, and the modified embedded atom method (MEAM), are respectively conducted to investigate the lattice distortion effect on Young’s modulus E (hkl) and Poisson’s ratio ν (hkl, θ) along [100], [110], and [111] loading directions for several fcc metals composed of 1 ∼ 5 atomic types, including Ni, Ni98W2, Ni96W4, FeCrNi, and CoNiCrFeMn HEAs. Also, a method is used to analyze the performance of the individual element on the elastic properties in the HEA environment. As a result, it can be unveiled that the effect of electron density inconsistency is more dominant than the effect of lattice distortion associated with the atomic size difference. The electronic configuration in the HEA environment plays a major role in elastic anisotropy while the difference of the atomic radii does the minor one. The anisotropy of CoNiCrFeMn HEA analyzed by this work is also consistent with in-situ neutron diffraction measurements.

Summary: A 34-year-old para 2 + 0 Indonesian woman presented with persistent right-sided gestational gigantomastia some 24 months following delivery. This was severely debilitating her activities of daily living, including caring for her children. On examination, she was found to have extreme hypertrophy of her right breast, which was nodular throughout on palpation. Biochemical investigations were unremarkable and revealed no obvious etiology. Magnetic resonance imaging identified grossly enlarged right breast tissue with prominent vessels. Given the minimal involution of her breast over the 24 months postpartum, she elected for a breast reduction with free nipple grafting following appropriate counseling. This was performed through excision of breast parenchyma preserving superior-medial tissue, followed by a free nipple graft.

In this study, two kinds of hydroxyethyl methacrylate–polyurethane (HEMA–PU) were used as volume shrinkage modifiers, and several hydroxyethyl methacrylate–polyurethane modified unsaturated polyester (HEMA–PU/St./UP) resins crosslinked with styrene were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and in terms of their mechanical properties, including their tensile strengths and Izod impact energies. The properties of the HEMA–PU–modified St./UP and St./UP were compared for potential applications as matrices for glass fiber-, aramid fiber-, and UHMWPE fiber-reinforced composites. The effects of the HEMA–PU content and the type of polyol in the HEMA–PU resin matrices of the composites were investigated through testing of their mechanical properties, bulletproof testing, and observations of their morphologies.

In this study, nanoscale organic rigid-rod compounds were utilized as self-reinforcing composites to enhance the physical properties of an epoxy resin diglycidylether of bisphenol A (DGEBA). First, DGEBA was used to react with an aromatic diisocyanate of methylene diphenyl isocyanate (MDI) to form an urethane linkage. Next, four different organic rigid-rod compounds including 4′-hydroxyphenyl-4-hydroxybenzoate, phenyl 4-hydroxybenzoate, 4,4′-isopropylidenediphenol, and 2-naphthol were incorporated to react individually with the remaining isocyanate groups of the MDI units after the previous step. Finally, the four different rigid-rod-modified DGEBA systems were examined using nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, scanning electric microscopy, and mechanical property analyses. Each of the four rigid-rod-reinforced DGEBA systems exhibited greatly improved mechanical properties, e.g., higher tensile strengths and fracture energies. POLYM. ENG. SCI., 47:1281–1288, 2007. © 2007 Society of Plastics Engineers

Two surface modification methods—plasma surface treatment and chemical agent treatment—were used to investigate their effects on the surface properties of ultrahigh-molecular-weight polyethylene (UHMWPE) fibers. In the analyses, performed using electron spectroscopy for chemical analysis, changes in weight, and scanning electron microscope observations, demonstrated that the two fiber-surface-modified composites formed between UHMWPE fiber and epoxy matrix exhibited improved interfacial adhesion and slight improvements in tensile strengths, but notable decreases in elongation, relative to those properties of the composites reinforced with the untreated UHMWPE fibers. In addition, three kinds of epoxy resins—neat DGEBA, polyurethane-crosslinked DGEBA, and BHHBP-DGEBA—were used as resin matrices to examine the tensile and elongation properties of their UHMWPE fiber-reinforced composites. From stress/strain measurements and scanning electron microscope observations, the resin matrix improved the tensile strength apparently, but did not affect the elongation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 655–665, 2007

An open clinical trial of thymopentin was conducted on 16 children with severe atopic dermatitis. The patients were treated with injections three times a week of 50 mg thymopentin for six weeks. They were then divided randomly into two groups: group A continued thymopentin for an additional six weeks, and group B were treated with normal saline. Clinical parameters and immunological function were evaluated serially. The total severity score started to decline from baseline significantly three weeks after treatment, and continued throughout the study period in group A but began to flare up in group B two weeks after stopping thymopentin. All the eight patients in group A completed the trial but three out of eight in group B dropped out because of flaring up of skin lesion. In vitro production of interleukin-4 tended to decrease and that of interferon gamma tended to increase, but total serum IgE, in vitro IgE synthesis, and abnormally low CD8+ CD11b+ suppressor T cells remained unchanged. Histamine releasing factor (HRF), plasma histamine, and respiratory burst activities of polymorphonuclear leucocytes were appreciably decreased after thymopentin treatment. It is concluded that the clinical efficacy of short term thymopentin treatment very possibly results from the decreased production of HRF and decreased release of polymorphonuclear leucocyte derived inflammatory mediators and may have no relation with antigen-IgE immune reaction.

The authors are indebted to the collaborators in the participating centres and all parents, children, teachers and other school staff who participated in the surveys. There are many field workers and funding agencies who supported data collection and national, regional and international meetings, including the meetings of the ISAAC Steering Committee. Unfortunately, these are too numerous to mention (they are acknowledged elsewhere) but the authors particularly wish to thank the funders who supported the ISAAC International Data Centre including the Health Research Council of New Zealand, the Asthma and Respiratory Foundation of New Zealand, the National Child Health Research Foundation, the Hawke’s Bay Medical Research Foundation, the Waikato Medical Research Foundation, Glaxo Wellcome New Zealand and Astra New Zealand, as well as Glaxo Wellcome International Medical Affairs for finding the regional coordinating centres. The International Data Centre is now supported by a grant from the BUPA Foundation., The International Study of Asthma and Allergies in Childhood (ISAAC) Phase One showed large worldwide variations in the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema, up to 10 to 20 fold between countries. Ecological analyses were undertaken with ISAAC Phase One data to explore factors that may have contributed to these variations, and are summarised and reviewed here. In ISAAC Phase One the prevalence of symptoms in the past 12 months of asthma, rhinoconjunctivitis and eczema were estimated from studies in 463,801 children aged 13 - 14 years in 155 centres in 56 countries, and in 257,800 children aged 6-7 years in 91 centres in 38 countries. Ecological analyses were undertaken between symptom prevalence and the following: Gross National Product per capita (GNP), food intake, immunisation rates, tuberculosis notifications, climatic factors, tobacco consumption, pollen, antibiotic sales, paracetamol sales, and outdoor air pollution. Symptom prevalence of all three conditions was positively associated with GNP, trans fatty acids, paracetamol, and women smoking, and inversely associated with food of plant origin, pollen, immunisations, tuberculosis notifications, air pollution, and men smoking. The magnitude of these associations was small, but consistent in direction between conditions. There were mixed associations of climate and antibiotic sales with symptom prevalence. The potential causality of these associations warrant further investigation. Factors which prevent the development of these conditions, or where there is an absence of a positive correlation at a population level may be as important from the policy viewpoint as a focus on the positive risk factors. Interventions based on small associations may have the potential for a large public health benefit., peer-reviewed

Four children with chronic arthritis (3 juvenile rheumatoid arthritis and 1 juvenile ankylosing spondylitis) and poorly controlled chronic uveitis, were given sulphasalazine (SASP) therapy for a mean period of 3.3 years. Three patients showed an excellent response, as evidenced by a reduction of inflammatory cells in the anterior chamber of the eyes and improvement of visual acuity. The response occurred after a mean of 7.7 weeks. These data suggested SASP therapy may have a role in the treatment of chronic anterior uveitis in children with chronic arthritis.

The purpose of this study was to investigate the prevalence and risk factors of latex-allergy in hospital personnel and the presence of latex-specific IgE in a latex-allergic group in Taiwan. A total of 1,021 hospital employees were initially screened for latex allergy with a questionnaire, which included sex, age, job categories, number of years of employment, daily working hours, frequency of latex glove wearing, symptoms of immediate reactions to latex gloves and history of previous atopic diseases. Among them, 70 hospital employees (6.8%; 95% confidence interval 1.9%-11.8%) had symptoms associated with glove wearing. The frequencies in different job categories were 28.3% of surgical nurses, 9.2% of surgeons, 5.8% of regular floor nurses, 5.2% of technicians, 4.6% of physicians, and 4.5% of laboratory researchers. The symptoms were significantly related to the frequency of latex glove exposure, surgical work, current hand eczema and history of atopic dermatitis. In contrast, the number of years of employment, daily working hours and previous history of hand eczema were not correlated with the symptoms of latex allergy. Latex-specific IgE was assayed by the dot blot method in 36 hospital employees of the latex allergic group (positive rate, 55.6%). We concluded that the prevalence of latex-allergy among hospital personnel was 6.9% and certain predisposing factors such as atopic dermatitis, current hand eczema ad surgical work may play a critical role in triggering and aggravating the symptoms.

We describe the successful use of HLA-compatible sibling bone marrow transplantation (BMT) in a 17-month-old Chinese boy in whom Wiskott-Aldrich syndrome (WAS) was diagnosed on the basis of eczema, thrombocytopenia, recurrent otitis media and abnormal immunological tests. The conditioning chemotherapy included 2 days' oral busulfan, 40 mg/m2/6 hours, and 2 days' intravenous cyclophosphamide, 60 mg/kg/day (BU2CY2). Complete hematological chimerism was achieved 3 weeks after transplantation. Eight months after his BMT the eczema has resolved, platelet count is normal, and he no longer has frequent infections. BU2CY2 as a preconditioning regimen gave complete lymphohematopoietic engraftment in this WAS patient with no evidence of graft-versus-host disease. The excellent clinical response of this patient and the inevitable fatal outcome of WAS support the opinion that where a histocompatible donor is available, BMT at the earliest opportunity is the best option. We believe this is the first case of successful BMT in a Chinese patient with WAS.

Forty-one children, aged six to 36 months (mean, 23.3 months), with a past history of acute bronchiolitis with or without recurrent wheezing episodes were treated with either a beclomethasone dipropionate metered dose inhaler 150 microgram twice daily, or a placebo for 12 weeks. Aerosols were inhaled through an AeroChamber (Trudell, Canada) using a mask. The patients were followed up biweekly. The two groups were well matched in anthropometric data and frequency of wheezing prior to the study being undertaken. At the end of four to six weeks, the beclomethasone dipropionate treatment group showed a significant improvement in both wheezing and sleep patterns, and systemic steroid therapy was able to be tapered. No significant side effect could be ascribed to this treatment.

Fifty-six Dermatophagoid farinae (D.f)-sensitive asthmatic children were hyposensitized by D.f-crude extract for two years. Serum total IgG subclass antibodies and D.f-specific IgE and IgG subclass antibodies were measured by ELISA before and after 2 years of treatment. The results showed that 1) After two years of treatment, there were significantly higher levels of total serum IgG1 in both responder and non-responder groups than those before treatment (p less than 0.01). The responder group also had significantly higher values of total IgG2 and IgG4 after immunotherapy (IT) (p less than 0.05), but not in the non-responder group. 2) The serum levels of D.f-specific IgG3 and IgG4 antibodies in responder group increased significantly after IT (p less than 0.05). On the contrary, the D.f-specific IgE and IgG1 IgG1 in the responder group were significantly lower than those before IT. No signi- in the responder group were significantly lower than those before IT. No signi-body titres before and after IT was found in non-responder group. 3) There was a significant correlation between the total IgG4 and D.f-specific IgG4 antibody (r = 0.634, p less than 0.01). The correlation coefficient was 0.634. No correlation was found between the other IgG subclass antibodies and D.f-specific IgG subclass antibodies. 4) Correlations between the levels of D.f-specific IgE and IgG subclass antibodies were highly significant both in IT-responder and non-responder groups. There was a significant correlation between the levels of D.f-specific IgG1 and IgG4 in non-responders, while no relationship was observed in the responder group.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant interleukin-2 (rIL-2) and adriamycin were administered systemically to treat nine patients (age 15.5-68 years, mean 48.9 +/- 15.5 years) with far advanced primary hepatocellular carcinoma. Three patients were newly diagnosed, and the remaining patients had received surgery, transcatheter arterial embolization, chemotherapy and other treatments but without improvement. rIL-2 was given at a dose of 10,000 to 30,000 units/kg every 8 hours for consecutive 9 days, and on the fifth day, a single dose of adriamycin 30 to 60 mg/m2 was administered. Four patients interrupted the immunotherapy because of severe intolerable side effects, 4 patients completed one course and the remaining one received 2 courses of treatment. Various adverse reactions were encountered, however, they subsided promptly after stopping therapy. All patients failed to respond to the regimen. Primary hepatic tumors continued to enlarge in 8 patients and remained unchanged in one, and pulmonary metastasis also increased in size and number in 4 patients. Transient decrease in serum alpha-fetoprotein was found in 6 patients. These results suggest that systemic IL-2 immunotherapy, even in combination with chemotherapy, is not effective for the treatment of far advanced hepatocellular carcinoma. However, in view of its immune amplifying effect, rIL-2 in combination with other treatment modalities may still be worth trying in early stages of hepatocellular carcinoma.

Peripheral blood monocytes obtained from 8 colorectal cancer patients and 6 normal controls were incubated in vitro with interferon-r (IFN-r) in the presence of bacterial lipopolysaccharide (LPS). The cytotoxic properties of the monocyte were determined subsequent to the interaction with radiolabeled autologous, allogeneic, as well as cultured colorectal cancer cells. Monocytes from normal controls and all colorectal cancer patients were activated in vitro to become tumoricidal; monocytes lysed tumorigenic cells but not nontumorigenic cells. Activators of protein kinase C (e.g. phorbol esters, PMA) and Ca2+ ionophores (A23187) when added alone did not effect the activation state of the monocyte. Whereas, PMA and A23187 cooperatively reproduced the ability of IFN-r to prime monocytes for tumoricidal activity. In the presence of PMA, A23187, and EGTA, the addition of excessive Ca2+ was sufficient for priming, whereas the addition of excessive Mg2+ was much less efficient. Priming by IFN-r, however, was not blocked by EGTA. An efflux of Ca2+ from preloaded monocytes was significantly increased by A23187 and by IFN-r. Quin-2/AM, an intracellular chelator of Ca2+, blocked priming by IFN-r. The results suggest that priming of monocytes for tumoricidal function by IFN-r may be involved in the activation of protein kinase C and mobilization of intracellular Ca2+.

The cell-mediated immunity in 19 patients with stage I and II cervical carcinoma was evaluated before and after postoperative PS-K immunotherapy. Lymphocyte subpopulations were enumerated using specific monoclonal antibodies (moAbs) of the Leu series (Leu2, Leullb, Leu15, and Leu19) and the OKT series (OKT3, and OKT4). A 4-hour 51Cr-release assay was used to measure natural killer (NK) cell activity. Serum levels of interleukin-2 (IL-2), soluble interleukin-2 receptor (IL-2R), and tumor necrosis factor (TNF) were also determined before and after postoperative PS-K immunotherapy. The results showed that the number of cells carrying the marker of a non-major histocompatibility complex (MHC), restricted cytotoxic lymphocytes in the peripheral blood and NK activity at three different effector/target ratios increased significantly after postoperative PS-K immunotherapy. It is therefore concluded that postoperative PS-K immunotherapy enhanced the NK activity in patients with cervical carcinoma, in which NK activity tended to be lower. Further clinical investigation to assess the effectiveness of PS-K immunotherapy in improving the overall survival is in progress.

Peripheral blood mononuclear cells (PBMC) were cultured with phytohemagglutinin (PHA) in 46 colorectal cancer patients and 27 normal controls. By collectively comparing the cancer patients with the normal controls, the cancer patients had: (1) decreased interleukin-2 (IL-2) secretion, (2) fewer interleukin-2 receptor (IL-2R) expression on cell surface, and (3) less 3H thymidine incorporation. The ability of the phorbol ester, phorbol 12-myristate 13-acetate (PMA), and the calcium ionophore, A23187, in co-stimulation with PHA, to enhance the IL-2 secretion, IL-2R expression and 3H thymidine incorporation were studied in the PBMC of colorectal cancer patients. By adding A23187 into the PHA-stimulated PBMC from colorectal cancer patients, IL-2 production and IL-2R expression were increased up to levels equal to that obtained in PHA-stimulated PBMC from normal controls. Whereas there was no significant increase in proliferative response. However, PMA has no effect on all three parameters. A23187 is known to be effective in elevating cytosolic free Ca2+ and PMA is regarded as an activator of protein kinase C. Therefore, we may conclude that the impairment of IL-2 production and IL-2R expression in PHA-stimulated cultures is mainly due to failure of the free Ca2+ release which can be repaired by A23187. While protein kinase C activation may not be impaired since its deficit in IL-2 production and IL-2R expression can not be corrected by PMA.

The G2m(n) allotype was significantly increased in Chinese female and high autoantibody cases, and in caucasians with pure ocular myasthenia, or undetectable autoantibody. In contrast to the strong Glm(x) association reported in Japanese, no overall Gm haplotype, or Am or Km allotype association was found in 90 (Taiwan) Chinese and 181 caucasian myasthenia gravis patients.

Guinea pig T lymphocyte responses to a decapeptide antigen (NH1-Asp5-Ans6-Glu7-Glu8-Gly9-Phe10-Phe11-Ser12-Ala13-Arg14-OH) of human fibrinopeptide B (hFPB) were examined using various synthetic peptide analogues containing single residue substitutions. Each analogue was examined for antigenicity as determined by an in vitro proliferative responses of hFPN-immune strain 2 guinae pig T cells. In addition, both strain 2 and strain 13 animals were immunized with each analogue and immunogenicity assessed by in vitro T cell-proliferative responses with the homologous immunizing analogue and the parent peptide. Replacement of arginine14 with lysine formed an immunogenic analogue which showed no antigenic cross-reactivity with the native peptide in strain 2 T cell responses. In addition, substitution of arginine14 with blocked lysine again produced a unique immunogenic analogue that showed little or no antigenic identity with the intact lysine analogue or the native peptide. In similar fashion, substitution of resideu phenylalanie10 with tyrosine or Phe(4-NO2) created unique immunogenic analogues with little or no antigenic identity to the native peptide with strain 2 T cells. By contrast, replacement of phenylalanine11 with either tyrosine or Phe(4-NO2) resulted in analogues with a total loss of immunogenicity and antigenicity in strain 2 T cell responses. An analogue in which glutamic acid7,8 were replaced with glutamine retained a small degree of antigenicity with hFPB-immune T cells, but T cells from strain 2 animals immunized with the Gln analogue responded only marginally to the Gln analogue while producing good proliferative responses with the native peptide. On the other hand, an analogue in which asparatic acid5 was replaced with asparagine retained most of the antigenic identity with hFPB for strain 2 T cell responses. None of thee analogues were immunogenic for strain 13 guinea pigs. These observations are discussed with respect to the contribution of each substituted residue to T cell respones, mechanism of Ir gene function, and a model for T cell recognition of small peptide antigens.

Lymphokine activated killer cell is a newly described lytic system against a variety of solid tumours and is distinct in several respects from the classic cytolytic T cell and the natural killer systems. This study was conducted to evaluate the lytic activity of lymphokine activated killer cells against fresh autologous and allogeneic, as well as cultured hepatocellular carcinoma cells. Lymphokine activated killer cell was generated by incubating peripheral blood mononuclear cells with various concentrations of recombinant IL-2 (rIL-2, Cetus, USA) for various periods of time. A four hour 51Cr release assay was used to measure cytotoxicity. The results show that fresh and cultured hepatocellular carcinoma cells were only slightly susceptible to natural killer cells. Normal hepatocytes were resistant to lymphokine activated killer-mediated lysis. Lymphokine activated killer cells could be generated from mononuclear cells of hepatocellular carcinoma patients and normal subjects with lytic activity against fresh autologous and allogeneic and cultured hepatocellular carcinoma cells, but lymphokine activated killer cells from the former was less efficient than that from the latter. It is concluded that the adoptive immunotherapy with combined rIL-2 and lymphokine activated killer may be worth trying in early cases of primary hepatocellular carcinoma.

Interpenetrating Polymer Networks (IPNs), composed of polyurethane (PU) and poly(styrene-acrylic acid) (PSAA), with containing mutual opposite charge groups, i.e., tertiary amine group in PU and carboxyl groups in PSAA, were prepared in PU/PSAA ratio of 75/25 (PU-dominated), and 25/75 (PSAA-dominated). The compatibility and morphology of these IPNs were investigated through dynamic mechanical analysis and scanning electronic microscopy studies. Compatibility of IPNs was greatly enhanced through the introduction of charge groups into the system. There are different morphology and dynamic mechanical behaviours for PU/PSAA alloys between PU-dominated and PSAA-dominated alloys. PSAA in the PU-dominated alloys was found to aggregate to the hard segment of the PU matrix, resulting in heterogeneous distribution of hard/soft segments in morphology and having little effect on the shift of the temperature transition while PU in PSAA-dominated alloys was found to be distributed homogeneously in the PSAA matrix.

Guinea pig T lymphocyte responses to the octapeptide antigen angiotensin II (NH(2)-Asp(1)-Arg(2)-Val(3)-Tyr(4)-Ile(5)-His(6)-Pro(7)-Phe(8)-OH; AII) were examined using various synthetic peptide analogues and homologues. Each peptide antigen was assessed for immunogenicity and antigenicity in strain 2 and strain 13 guinea pigs as determined by in vitro T cell proliferative responses. The genetic control of T cell responses to these peptides was found to be highly specific and capable of distinguishing subtle differences in the antigens. For example, strain 2 guinea pigs responded to AII and were low responders to [Val(5)]-AII, whereas strain 13 animals responded to [Val(5)]-AII but not to AII. The genetic control in this case involved the difference of one methyl group between Val(5) and Ile(5). Differences in T cell responsiveness by strain 2 and strain 13 guinea pigs were also observed with analogues involving para substitutions on the phenyl ring of Tyr(4) and of Phe(8). However, the genetic regulation of T cell responses did not seem to be based on a single peptide residue. For example, removal of Asp(1) allowed strain 13 animals to respond to the Ile(5)-containing analogue, but eliminated responsiveness to the Val(5)-containing analogue. Thus, the first and fifth AII residues are both involved in the regulation of strain 13 T cell responses. Substitutions for Tyr(4) and Phe(8) suggested that the same residue may serve to alter the specificity of T cell responses in one strain, and determine responsiveness or unresponsiveness in the other strain. One of the most striking observations is that T cell responsiveness to the various AII analogues and homologues randomly fluctuates between strain 2 and strain 13 guinea pigs, and in general neither strain responds to the same peptide antigens. This suggests that strain 2 and strain 13 T cell responses are rarely directed against the same antigenic determinants, and that the T cell antigen-combining diversity is usually exclusive between these two strains. These results are discussed with respect to the specificity of Ir gene control and the relationship between Ir gene function and antigen recognition by T cells. Note added in proof: More recent experiments using a new lot of [Val(5)]- AII have indicated that [Val(5)]-AII-immune strain 2 T cells show significant stimulation with AII but remain relatively low responders with [Val(5)]-AII, as shown in Table I. The difference in priming for cross-reactivity for AII with the different lots of [Val(5)]-AII is at present unknown.

In order to elucidate the working mechanisms of immunotherapy (IT), the in vitro productions of histamine, prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) were studied in 18 newly diagnosed and 20 hyposensitized (greater than 2 yr) asthmatic children. All were sensitive to house dust and dust mites. (D. pteronyssinus). Ten age-matched normal children were included as control. Polymorphonuclear (PMNs) and mononuclear (MNCs) leukocytes were separated by density gradient centrifugation and dextran sedimentation. PMNs (2 x 10(7) cells/ml) and MNCs (2 x 10(7) cells/ml) were stimulated with mite allergen (10 micrograms/ml) and calcium ionophore A23187 (1 microgram/ml) for 15 minutes. The plasma and culture supernatant (sup) histamine levels and sup PGE2 and LTC4 were measured by RIA. The results showed; 1) When compared to new patients, the treated patients had much lower plasma and sup histamine (p less than 0.001), no matter whether PMNs and MNCs were stimulated with allergen or A23187 and the normals had the lowest histamine level among 3 groups; 2) LTC4 in A23187-stimulated sup was lower in treated patients (p less than 0.05); 3) The PGE2 in allergen-stimulated sup was markedly increased in treated patients as compared to new patients (p less than 0.01) and the PGE2 in sup of normals was also much higher than that of new patients. Thus, immunotherapy is able to reverse the abnormal secretory pattern of inflammatory mediators of allergic patients, and this change may account, partly, for its clinical effectiveness.

Patients with allergic diseases are characterized by the presence of elevated serum IgE and specific IgE antibodies against a variety of environmental allergens, especially house dust, mites and molds in Taiwan. A series of studies on allergic asthmatic children have been conducted to explore the non-immunological and immunological causes for their augmented production of IgE antibody and to explore the working mechanisms of hyposensitization. The results showed that the patients had multiple defects in their defects in their defense mechanisms, including hyper-permeability of mucosae, hyperreactivity of target organs, defective phagocyte functions, and deficient helper and suppressor T-cell functions. Hyposensitization was able to partially correct the immunological aberrations. More over, a newly found lymphokine termed "T-cell growth factor" or "interleukin 2" may be used not only as an indicator for the initiation and termination of hyposensitization, but may also provide a promising tool for the treatment of allergic diseases in the future because of its capability of enhancing and expanding allergen-specific suppressor T cells.

Two patients with recurrent sinopulmonary infections and normal total serum immunoglobulin levels were found to have selective deficiencies in IgG subclasses. The serum of one patient contained abnormally low IgG2 and IgG4; and the other was deficient in IgG4. Both patients responded to the treatment with high dose intravenous immunoglobulin. The experiences on these two cases strongly suggest that IgG subclasses should be checked in patients with recurrent sinopulmonary infections in face of normal total immunoglobulins.

Recombinant interleukin-2 (RIL-2) and lymphokine-activated killer (LAK) cells were administered to 2 boys with the end-stage of primary hepatocellular carcinoma (HCC); the efficacy and toxicity were evaluated. Immunologically, the natural killer and LAK activities were enhanced. Clinically, the side effects were similar to those reported for adults but milder. This kind of treatment may be considered for children with the early stages of hepatocellular carcinoma.

To explore the working mechanism(s) and the safety of long-term hyposensitization (HS) with house dust (HD), a series of studies were undertaken on 30 newly diagnosed and 30 hyposensitized asthmatic children. Twenty age- and sex-matched school children were included as control. The results showed: (1) HS was able to decrease the total serum IgE and increase the production of allergen-specific IgG blocking antibody, however, the allergen-specific IgE antibody remained nearly the same after HS for a couple of years, (2) Normal controls had allergen-specific IgG antibody but no IgE antibody, (3) Circulating immune complex concentration in the treated group did not differ significantly from the untreated group, (4) HS was able to suppress in vivo and in vitro histamine production and restore polymorphonuclear leukocyte (PMN) function in terms of Fc gamma R expression. These results suggest that HS is a specific and safe treatment, and provide solid rationale for its use in the treatment of respiratory allergic disease.

Two Chinese families with X-linked chronic granulomatous disease (CGD) are reported. The first case was an 11-month-old male baby and the second a 2-month-old male baby. Both patients presented with persistent infections caused by Staphylococcus and Candida since birth. Neutrophil functions were studied in patients and a number of family members. Chemotaxis and phagocytosis were normal in every subject. Slide and spectrophotometric nitroblue tetrazolium (NBT) tests of both patients were abnormal and remained unchanged in spite of treatment with ascorbic acid, levamisole, sulfamethoxazole, trimethoprim and isoniazide. Mothers were proved to be carriers as evidenced by the presence of both normal and CGD phagocytes in the slide NBT test. During the 2-month follow-up period, the percentage of normal phagocytes from the mother of case 1 varied from 12% to 73%, which correlated with the fluctuation of spectrophotometric NBT value. The slide NBT test of the mother of case 2 was nearly normal in face of the presence of CGD phagocytes. Both carrier mothers were healthy and asymptomatic.

Modulation-doped Ga0.47In0.53As/Al0.48In0.52As heterojunctions were grown by molecular beam epitaxy. Electron mobilities were measured at room temperature and 77 K as a function of undoped Al0.48In0.52As spacer layer thickness and sheet carrier concentration. Enhanced mobilities were as high as 10 900 cm2V−1s−1 at room temperature and 55 500 cm2V−1s−1 at 77 K in these samples with sheet carrier concentrations at 1 33 × 1012 cm−2 (room temperature) and 1.26 × 1012 cm−12 (77 K).