A high density cell culture system for generation of human lymphokine-activated killer (LAK) cells for clinical use in adoptive immunotherapy

A high density cell culture system has been developed for large-scale production of lymphokine-activated killer (LAK) cells from peripheral blood lymphocytes (PBLs) of malignant tumor patients. The system consists of a culture bag, which has two compartments separated by a semipermeable membrane, and an external rotator. The system allows for a long-term, at least 4 weeks, culture of LAK cells at high cell density in the inner compartment. The collected PBLs were first divided between the two culture bags and cultured without harvesting for 7-10 days to obtain LAK cells. Half of the LAK cells from each bag was administered to patients twice a week for clinical trials. Culture of the remaining half was continued following addition of a fresh culture medium. LAK cells were transferred to patients alternatively from each bag for the following 2-3 weeks. The total number of LAK cells administered amounted to 3.9-9.8 (mean 5.8) times more than the PBLs collected by leukapheresis (n = 10). The 5 x 10(6)/ml of PBLS of the initial concentration reached a maximum of 2 x 10(7)/ml. Our system does not need for a CO2 incubator. Cytotoxicity of the LAK cells was evaluated in 4 hr 51Cr release assays. Mean cytotoxicity at maximum cell density was 95.4 +/- 3.2% against ONS-12 (a human glioma cell) and 84.8 +/- 3.0% against Daudi cells (n = 10), but gradually decreased to about 50% at the end of fourth week of the culture period. Cell viability of the LAK cells was normally over 80% through the entire culture period.(ABSTRACT TRUNCATED AT 250 WORDS)

Interleukin-2 induces motility of human lymphocytes, but not their mobility

Interleukin-2 induces cytotoxic and antitumor activities of human lymphocytes. For the expression of these activities, the cytoskeletal system is probably activated. This study was do;ne to find if interleukin-2 causes cell movement. Lymphocytes were incubated with interleukin-2, and their morphology and motile activities were studied. After 72 hr of incubation, some 29% of lymphocytes were larger than before; nucleoli had formed and the microvilli were well-developed. The membrane potential of the lymphocytes increased during incubation. Motility under agar after 3 days of incubation with interleukin-2 was examined. Cells aggregated in clumps in the incubation well, and migration was not observed. When mobility was examined with Boyden's method, fewer cells incubated with interleukin-2 migrated than in control preparations. Cells incubated with interleukin-2 were extracted with Triton X-100. The extract obtained had three more bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis than the controls. The band were at the positions for the molecular weights of 270,000-300,000. We concluded that interleukin-2 activated the motility of lymphocytes, but not their mobility.

Goblet cell carcinoid of the appendix

We have reviewed all cases of goblet cell carcinoid in the Department of Pathology, Edinburgh University. Of the 10 cases identified, two had died as a result of the tumour. This would suggest a poorer prognosis than is generally recognized. Those patients who subsequently had progression of their disease were not predicted by histological criteria. Because of the unpredictable behaviour of these tumours we recommend that such patients should correctly be treated by a right hemicolectomy.

Effect of aggregation of histone octamers in high-salt solutions on circular dichroism spectra

The circular dichroism (CD) of freshly prepared chicken erythrocyte core histones has been reexamined in high concentrations of ammonium sulfate and sodium chloride, conditions which cause drastic changes in the solubility and aggregative properties of these proteins. After sample clarification by ultracentrifugation, no significant net changes are detected in the secondary structure of the core histones in the range of 2.0-2.5 M ammonium sulfate. There is also no significant difference between the CD spectra of histone solutions in 2 M sodium chloride and clarified solutions of histones in high concentrations of ammonium sulfate. It was observed that sample clarification by ultracentrifugation immediately prior to taking CD spectra was necessary for signal stabilization, especially under conditions which begin to favor crystallization of the histones.

Assessment of bilirubin clearance capacity of a newly developed ion-exchange adsorption column and its possible use as a supportive therapy in hepatorenal syndrome

We assessed the bilirubin reduction capacity of three different types of devices in vitro: a high-permeable membrane column for double-filtration plasmapheresis (DFP) (Evaflux 2A, Kuraray, Japan), and non-coated charcoal column for hemoperfusion (HP) (N-180, Asahi Medical, Japan), and ion-exchange columns for plasma adsorption (PA) (BR-350, Asahi Medical, Japan, and B-001, Kuraray, Japan). A column for DFP reduced the concentration of low-molecular proteins effectively such as plasma bilirubin and bile acids in an albumin-dependent manner. A charcoal column adsorbed low-molecular substances preferentially. But in these two columns, the loss of fibrinogen is a limiting factor for determining the processing plasma volume. Ion-exchange columns for PA adsorbed bile acids, disconjugated bilirubin, and monoconjugated bilirubin more efficiently compared with delta-bilirubin and unconjugated bilirubin. Pretreatment of the column with heparin reduced the loss of fibrinogen to less than 10%. We applied the BR-350 ion-exchange column in vivo for treatment of three patients with hyperbilirubinemia. After treatment, an alcoholic hepatitis patient with the hepatorenal syndrome (HRS) recovered from acute renal failure. However, in a patient with primary biliary cirrhosis and in a patient with fulminant hepatitis, the decrease of serum bilirubin was transient and no obvious beneficial responses were noted. The capacity and ability of the BR-350 column to adsorb plasma bilirubin was shown sufficient to treat deeply jaundiced patients, because 4 liters of the plasma of a patient with 108 mg/dl of initial total bilirubin concentration was able to be processed continuously without an obvious decrease in bilirubin adsorption capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

Conformational analysis of the immunodominant epitopes of the circumsporozoite protein of Plasmodium falciparum and knowlesi

All of the coat proteins of the sporozoite and merozoite stages of Plasmodium, determined to date, contain tandem repeats and most of these contain at least one proline residue. These tandemly repeated segments of the circumsporozite (CS) proteins of P. falciparum and P. knowlesi have been shown to constitute an immunodominant epitope. Antibodies to these peptide segments have been shown to be protective and cause the shedding of the CS protein, known as the CSP reaction. In this study, four synthetic peptides were prepared by solid-phase peptide synthesis. The first peptide corresponds to the tetrapeptide tandem repeat in the CS protein of P. falciparum, repeated eight times, (NANP)8. The second peptide is an analogue of the first in which glycine is substituted for proline, (NANG)8. The third peptide corresponds to the tandem repeat of P. knowlesi, PK(1-24), which is repeated twice (QAQGDGANAGQP)2. The fourth peptide is a tetrapeptide repeat, corresponding to the C-terminal tetrapeptide of PK(1-24) and is repeated eight times, (AGQP)8. It is shown by CD measurements that the presence of proline in these repeats induces an increase in beta-sheet (beta-turn) content in the (NANP)8 peptide relative to the repeat of (NANG)8 and PK(1-24) peptide in aqueous media. The (AGQP)8 peptide has the highest beta-sheet (beta-turn) content of all peptides studied. The Chou-Fasman predictive algorithm indicates a high beta-turn content in the synthetic peptides. It is concluded that this increase in defined structure correlates well with and hence may contribute to the increased antigenicity in these repeats.

[Expression of major histocompatibility complex on human medulloblastoma cells]

Medulloblastoma is one of the most common malignant brain tumors in childhood. These cells are immature bipotential cells that could differentiate into both neuronal and glial cells. The authors established two human medulloblastoma cell lines. One was derived from a 2-year-old girl with cerebellar tumor (designated as ONS-76) and another was from a 9-year-old girl with metastatic tumor in the right frontal lobe (ONS-81). Immunohistochemical studies showed that both cell lines possessed 145 and 200 kDa neurofilament proteins and neuron-specific enolase, without glial fibrillary acidic protein and S-100 protein. It was shown that interferon gamma could enhance or induce the expression of the major histocompatibility complex (MHC) antigens which play a major role in immune response. Also shown for the first time was the expression of MHC class II antigens on human medulloblastoma (ONS-76 and 81) with neuronal differentiation.

Morphological characterization of surface-induced platelet activation

Morphological changes of platelets activated on glass and dimethyldichlorosilane-treated glass were investigated using video microscopy. The platelet morphological changes were quantified by measuring the area and circularity of spreading platelets. In addition, re-organization of cytoskeletal structures of spread platelets was examined. The effects of precoated albumin and fibrinogen on the platelet spreading kinetics were examined as a function of surface protein concentrations. Results showed that platelet shape changes were very sensitive to the surface concentration of precoated proteins. In general, platelets on fibrinogen-precoated surfaces spread fully to a circular shape and developed an extensive inner filamentous zone. In the presence of albumin on the surface, however, platelets could not spread fully and the development of the inner filamentous zone was very poor. For both albumin and fibrinogen, the maximum effects of precoated proteins on platelet shape changes were observed when the surface protein concentration reached the monolayer concentration.

Surgical correction of astigmatism using paired T-incisions

Transverse incision astigmatic keratotomy procedures were performed, combined with radial keratotomy, in 16 eyes for correction of astigmatism and coexisting myopia. We used a transverse incision technique in which T-incisions vertically intersected radial incisions of the steepest corneal meridian. After a mean follow-up period of 10 months with a range of six to 27 months, an average 1.92 diopters of the cylinder was corrected. In comparison with 2.11 diopters of the cylinder corrected at postoperative one day, there was a 22.8% decrease in the effect of astigmatism correction after a postoperative period averaging 10 months.

[Treatment of acute leukemia with "MB-triple V" therapy--a comparative study of "MB-triple V" therapy and B-triple V therapy]

Eleven patients with acute leukemia were treated with MB-triple V therapy consisting of mitoxantrone, behenoyl-arabinoside, etoposide, vincristine and vindesine. In this regimen, the target points were set for WBC count in the peripheral blood (less than 1,500/microliters) and TNC count in the bone marrow (less than 15,000/microliters). In this study, we compared the WBC count in nadir state and the duration until WBC count returned to above 1,000/microliters between 11 patients with MB-triple V therapy and 15 patients with B-triple V therapy in which target points were not set. In particular, the standard distribution of WBC count in nadir state of MB-triple V group was significantly smaller than that of B-triple V group. The number of early deaths in the course of MB-triple V (0/11, 0%) decreased compared with B-triple V group (3/15, 20%). Seven patients of the eleven patients with this regimen achieved CR state (63.6%). Hereafter, further cases are necessary before this combination chemotherapy as a part of the induction therapy is evaluated.

The clinical report on six cases of epikeratoplasty

After the first description of epikeratoplasty for the correction of aphakia by Kaufman in 1980, the application of epikeratoplasty has been extended further to the treatment of keratoconus and high myopia. Six epikeratoplasty for five eyes of high myopia and one eye of keratoconus were performed and followed up for an average of 4.9 months. All cases improved their uncorrected visual acuity, and the preoperative best corrected visual acuity improved or had no change postoperatively except for one case. In the cases of high myopia, the mean preoperative spherical equivalent of -19.4 D was corrected to an average -0.23 D with a range of -1.0 D to +2.5 D postoperatively. In the case of keratoconus, there was a mean decrease in 12.0 D of myopia in terms of the spherical equivalent, and the cornea was flattened by over 8 D in keratometry readings.

[Adoptive immunotherapy in patients with medulloblastoma by LAK cells]

Medulloblastoma is one of the most popular malignant brain tumors in children. It accounts for about 15% of all pediatric brain tumors. Radiochemotherapy has prolonged the 5-year survival rate up to 60-85% for patients with medulloblastoma. But the conventional therapy is not so effective to recurrent cases, especially with meningeal dissemination, and generally fatal. There remains a big problem of the neurotoxicity to infants in a growth process under the whole-neuraxis irradiation and chemotherapy. Aiming to relieve the radiation and antitumor drugs, adoptive immunotherapy is greatly expectant. We have had clinical trials of adoptive immunotherapy for 8 patients with medulloblastoma by lymphokine-activated killer (LAK) cells. They were from 2-9 years in age and had cerebrospinal fluid (CSF) dissemination of the tumors. All patients underwent the whole-neuraxis irradiation and chemotherapy. After they had CSF dissemination, they were submitted to an adoptive transfer of allogeneic LAK cells. LAK cells were induced from peripheral blood lymphocytes (PBL) of their relatives with human recombinant interleukin-2. 3-15 x 10(9) LAK cells were transferred intrathecally in 2-3 months. In 3 of 8 patients, neurological signs were improved and malignant cells had never been detected on CSF cytology after the adoptive immunotherapy. One among these 3 patients showed complete response in 20 months. Thus, this is an attractive treatment for patients with medulloblastoma, especially with CSF dissemination, which cannot be cured by current therapeutic intervention.

Attenuation in the regulation of the pyrBI operon in Escherichia coli. In vivo studies of transcriptional termination

The attenuation model for transcriptional regulation of the Escherichia coli pyrBI operon is based on the assumption that transcription terminates upstream of the structural genes at a rho-independent terminator when cells contain high levels of UTP. When, however, the cells are limited for pyrimidines, the presence of ribosomes translating the short leader peptide is presumed to cause an alteration in the secondary structure of the terminator in a way that allows RNA polymerase to transcribe the entire operon. These two premises of transcriptional regulation were tested by using exonuclease protection assays to map the 3' ends of transcripts extracted from cells containing either ample or depleted concentrations of pyrimidines. The results support the model since 99% of the pyrBI transcripts terminated at the (G + C)-rich region of dyad symmetry upstream of the structural genes when cells were grown in excess uracil. In addition, a significant portion (36%) of the pyrBI transcripts extracted from cells containing reduced pyrimidine concentrations extended past the dyad into the structural genes. This observation correlated with the amounts of aspartate transcarbamoylase synthesized in cells under the various conditions. The mapping technique was also used to determine the position of the 5' ends of the transcripts to measure contributions of two potential start sites (P1 and P2) to the pool of pyrBI transcripts. The results show that under all conditions no more than 3% of the total transcripts had 5' ends corresponding to the upstream promoter, P1. In cells lacking P1 virtually all transcripts from P2 terminated at the (G + C)-rich hairpin when the cellular level of pyrimidines was high. Conversely 57% of the transcripts extended past the terminator when cells were grown in UMP. The S1 nuclease technique also provided a measure of the steady state level of transcripts originating at P2. In cells depleted of pyrimidines there was a 5-10-fold increase in these transcripts depending on the number of copies of pyrBI. This increase, which is independent of attenuation, is caused by a different regulatory mechanism which as yet has not been identified.

Sensitivity-enhanced, common-mode-compensated Mach-Zehnder fiber-optic sensor circuit with electro-optic feedback

A Mach-Zehnder fiber-optic sensor circuit incorporating an optical compensation circuit to reduce errors from common-mode perturbations and electro-optic feedback to enhance measurand sensitivity is proposed and demonstrated. Experimental results show that the phase bias and the feedback constant can be adjusted to yield an operating region with negligible sensitivity to common-mode perturbations and a measurand sensitivity an order of magnitude above that expected from an equivalent conventional Mach-Zehnder sensor, in good agreement with theory.

[A colorimetric method for determination of delta-bilirubin in serum using bilirubin oxidase (Trachyderma tsunodae)]

We developed a colorimetric method to measure delta-Bilirubin in human serum using bilirubin oxidase from Trachyderma tsunodae and diazo reagent. In the first step, bilirubin fractions except for delta-Bilirubin, such as diconjugated, monoconjugated and unconjugated forms, are removed by enzymatic oxidation at pH 8.0 in the presence of sodium salicylate. In the second step, delta-Bilirubin remaining after enzymatic oxidation is determined by the conventional indirect diazo method. The results obtained by this method showed intra-day CV of 2.4%, satisfactory linearity and good correlation (r = 0.93, p less than 0.001) with those obtained by high performance liquid chromatography method. This simple and rapid method was clinical useful for determining the bilirubin fractions in sera of hepatic patients.

[Antitumor efficacy of FK 973 on malignant glioma cells]

FK 973, a new substituted dihydrobenzoxazine, was obtained by chemical modification of a novel antibiotic which was isolated from the fermentation products of streptomyces sandaensis No. 6897. FK 973 had cytotoxic effects against in vitro cultured human and murine glioma cells. The concentration of FK 973 required to inhibit cell growth by 50% was 0.06-5 micrograms/ml, after 2-day exposure of this drug against human glioblastoma (ONS-6, 12, 23, and ONS-12/ACNU), human medulloblastoma (ONS-76, 81), human neuroblastoma (ST), and murine glioblastoma (RSV-M glioma). FK 973 showed antitumor efficacy in the meningeal gliomatosis models by RSV-M glioma cells. The median survival time (MST) of models treated by FK 973 (i.t.) was 30 days. However, the MST of control group was 23 days. In the in vitro neurotoxicity test, FK 973 proved to be slightly more toxic than ACNU and MTX, but it had no crucial problems, compared with ADM.

[Establishment and biological characterization of human medulloblastoma cell lines]

Two cell lines of human medulloblastoma (ONS-76 and ONS-81) were established, and their biological characteristics were investigated. The cell line, ONS-76, was established from a tumor specimens obtained from a large cerebellar tumor of a 2-year-old girl. The pathological diagnosis was a typical medulloblastoma. The other cell line, ONS-81, was derived from a metastatic tumor in right frontal lobe of a 9-year-old girl. The tumor specimens were minced into fragments approximately 1 mm in diameter and cultured in plastic culture flasks in RPMI 1640 medium supplemented with 10% heat-inactivated fetal calf serum (FCS) and 50% patients serum. The cells growing as a monolayer were subcultured in RPMI 1640 supplemented with 10% FCS and initially with L-glutamine, sodium pyruvate, and nonessential amino acid. Microscopically, both cultured cells exhibited various morphological appearances, and this morphological heterogeneity seemed to be specific for medulloblastoma cells. The in vitro population doubling time of ONS-76 and ONS-81 were 18.6 and 19.2 hr, respectively. The ONS-76 and ONS-81 cells formed subcutaneous tumors in nude mice as serial transplantable xenograft, and these tumors had a microscopic appearance similar to that of the original medulloblastoma. Ultrastructurally++, the cultured cells showed primitive, undifferentiated appearance, and no neuronal or glial structures were not seen. Immunohistochemical studies showed that both cells expressed neuron-specific enolase (NSE) and neurofilament protein (NFP 200 K, 145 K), but glial fibrillary acidic protein (GFAP) and S-100 protein were not detected. The NFP immunoreactivities of both cultured cells were demonstrated as abnormal perinuclear deposits.(ABSTRACT TRUNCATED AT 250 WORDS)

Meal-induced peptide tyrosine tyrosine inhibition of pancreatic secretion in the rat

In the present studies we examined the distribution, release, and biological actions of peptide tyrosine tyrosine (PYY) in the rat. The concentration and distribution of PYY was highest in the ileum and colon as determined by both radioimmunoassay of rat tissue extracts and immunocytochemistry. An ultrastructural comparison of rat and dog colonic PYY cells revealed a bipolar distribution of peptide-containing secretory granules in both species. Serum PYY and pancreatic exocrine secretory responses were monitored after presentation of a meal to meal-trained rats (n = 12). A significant increase in PYY concentrations was not observed until 120 min after meal presentation, a delayed response similar to that previously observed in the dog. PYY responses were also observed in rats after perfusion of the intestine at the level of the duodenum and ileum with an 80 mOsm micellar solution of sodium oleate. Duodenal instillations of the fatty acids resulted in a maximum PYY response after 120 min, whereas rats subject to ileal perfusion of fat exhibited maximum PYY release within the first hour. In other experiments, infusion of exogenous PYY at 100 pmol.kg-1.h-1, which reproduced plasma PYY levels observed after a meal and perfusion of the gut with fat, significantly inhibited CCK-stimulated bile pancreatic volume (P less than 0.02), protein (P less than 0.01), and amylase (P less than 0.01) output. These studies demonstrate a bipolar distribution of PYY-containing secretory granules in cells of the jejunal, ileal, and colonic mucosa, and show that PYY is released in response to a meal in amounts sufficient to inhibit cholecystokinin-stimulated pancreatic secretion. Evidence is presented that PYY may mediate the delayed inhibition of pancreatic secretion that is observed in the rat after ingestion of a meal.

Structural features of the acetyl-CoA carboxylase gene: mechanisms for the generation of mRNAs with 5' end heterogeneity

Acetyl-CoA carboxylase [acetyl-CoA:carbondioxide ligase (ADP-forming), EC 6.4.1.2] is the rate-limiting enzyme in the biogenesis of long-chain fatty acids. We have previously characterized five acetyl-CoA carboxylase mRNA species that differ in their 5' untranslated regions but not in the coding region. We have now characterized the exon-intron structure of the genomic DNA that encodes the 5' untranslated region of the mRNA. Generation of different forms of the mRNA is the result of the selective use of two promoters and differential splicing of five different exons. These five exons contain a total of 645 nucleotides and they are scattered over a 50-kilobase-pair genomic DNA region that we have characterized.

Promotion of incompatible allograft acceptance in rhesus monkeys given posttransplant antithymocyte globulin and donor bone marrow. II. Effects of adjuvant immunosuppressive drugs

Previous studies from this laboratory demonstrated prolonged acceptance of MHC-mismatched kidney allografts in rhesus monkeys treated with posttransplant rabbit antithymocyte globulin (RATG)* and donor-specific bone marrow (DBM). Here we have investigated the effect of adjunctive immunosuppressive drugs on induction of allogeneic unresponsiveness in this primate model. Parameters examined included median kidney allograft survival time (MST), development of specific antidonor T lymphocyte-mediated cytotoxicity (LMC) and antidonor antibody-dependent cellular cytotoxicity (ADCC). Posttransplant infusion of DBM in RATG-treated kidney allograft recipients resulted in 70 days MST and a dramatic reduction in the incidence of antidonor LMC. However, development of antidonor ADCC was similar to that of RATG controls, suggesting an immune deviation or split tolerance in these animals. Adjunctive azathioprine did not have a beneficial effect in recipients given RATG & DBM, resulting in decreased MST and increased antidonor LMC responses. In contrast, adjunctive cyclosporine (CsA) and low-dose prednisone (P) exerted an additive immunosuppressive effect resulting in a 50% increase in MST and no detectable antidonor LMC. However, CsA & P appeared to enhance the humoral alloimmune response, increasing the incidence of recipients with antidonor ADCC. Long-term graft survival in this group was limited by chronic rejection and especially by CsA-associated toxicity. These studies point out deterrents and also directions for optimizing adjunctive immunosuppression in primates treated with posttransplant RATG & DBM. The results with CsA are relatively encouraging. However, the prevalence of alloantibody and of chronic rejection in these animals suggests that more homogeneous success with tolerance induction in this model may require adjunctive immunosuppressive strategies that reduce humoral immunity.

Protein adsorption on polymer surfaces: calculation of adsorption energies

In an attempt to understand the mechanisms of protein adsorption at the solid-liquid interface, we have calculated the interaction potential energy between the protein and the polymer surface by a computer simulation approach. The adsorption of four proteins--lysozyme, trypsin, immunoglobulin Fab, and hemoglobin--on five polymer surfaces was examined. The model polymers used for the calculation were polystyrene, polyethylene, polypropylene, poly(hydroxyethyl methacrylate), and poly(vinyl alcohol). All possible orientations of the protein on the polymer surfaces were simulated and the corresponding interaction energies for the initial contact stage of protein adsorption were calculated. In the calculation of interaction energies, the hydrophobic interaction was not treated explicitly owing to the difficulty in the theoretical treatment. The results showed that the interaction energy was dependent on the orientation of the protein on the polymer surfaces. The energy varied from -850 to +600 kJ/mol with an average of about -155 kJ/mol. The interaction energy was also dependent on the type of polymer. The average interaction energies of the four proteins with poly(vinyl alcohol) were always lower than those with the other polymers. The interaction energy was not dependent on the protein size. It was found that the dispersion attraction played the major role in protein adsorption on neutral polymer surfaces.

A pancreatic tumour presenting as a ruptured spleen

We report a case of spontaneous rupture of the spleen due to invasion from a pancreatic tumour. We are unaware of any similar case having been reported in the literature.

Enzyme-digestible swelling hydrogels as platforms for long-term oral drug delivery: synthesis and characterization

A method was developed for synthesizing enzyme-digestible swelling hydrogels. Albumin molecules were modified using glycidyl acrylate to introduce vinyl groups. The functionalized albumin molecules participated as cross-linkers in the polymerization of vinyl monomers, such as acrylic acid or acrylamide. The extent of chemical modification of albumin was an important variable in controlling the cross-linking ability. The albumin in the synthesized hydrogels retained its property of enzymatic digestion by proteolytic enzymes. The kinetics of swelling and enzymatic digestion of the hydrogels were examined using various enzyme concentrations. It was observed that the digestion kinetics were largely determined by the relative concentrations of albumin and enzyme. The potential application of the enzyme-digestible swelling hydrogels as platforms for long-term oral drug delivery is discussed.

An unusual case of oesophageal rupture treated by transhiatal oesophagectomy

Spontaneous rupture of the oesophagus is an uncommon surgical emergency. A case is presented in which the extensive nature of the rupture precluded standard methods of treatment and was treated by transhiatal oesophagectomy.

The histone octamer, a conformationally flexible structure

The conformation of the histone octamer complex in solution has been shown, by circular dichroism studies, to be highly dependent on the nature of the salt milieu and its concentration. In 2 M NaCl, the complex has 43.5% alpha-helix, 16% beta-sheet, and 40.5% random structure. In 2.3 M (NH4)2SO4, the octamer has 49.0% alpha-helix and 51% random structure. These results partially explain the discrepant results obtained by the X-ray analysis of crystals obtained under varying conditions.

Promotion of incompatible allograft acceptance in rhesus monkeys given posttransplant antithymocyte globulin and donor bone marrow. I. In vivo parameters and immunohistologic evidence suggesting microchimerism

This report extends previous studies demonstrating that prolonged acceptance of incompatible kidney allografts in rhesus monkeys can be achieved by a short recipient rabbit antithymocyte globulin (RATG) treatment course followed by donor bone marrow infusion on day 12 without a requirement for chronic immunosuppression. Serial studies of antilymphocyte cyctotoxic antibody in recipients' sera following RATG injections showed pan-lymphocyte-reactive antibody present until day 10 posttransplant. On days 11 and 12, pan-lymphocyte-reactive antibody was no longer detectable, but cytotoxic antibody specific for mature T cells remained in recipients' sera. These findings might explain the critical time relationship between antithymocyte globulin treatment and donor bone marrow infusion, and further suggest that the tolerance-promoting cell in donor bone marrow is not a mature T cell, but rather a pre-T or a non-T cell. Finally, it was found that this treatment protocol resulted in development of lymphoid nodules in the transplanted kidney that express a CD8-positive, FcIgG-receptor-positive phenotype and appear to be of donor origin. The possibility of a veto cell type of mechanism is discussed as an explanation for the promotion of allograft acceptance in this model.

Surface characterization of biomaterials by immunogold staining--quantitative analysis

The labeling of target proteins by immunogold particles has been analyzed based on Einstein's law of Brownian motion. The theory was confirmed from the experiments which employed antifibrinogen gold markers to label fibrinogen molecules adsorbed on the polyethylene surface. The theory predicts that the degree of labeling depends on the concentration of gold markers, temperature, medium viscosity, size of gold markers, and staining time. Of these factors most important is the concentration of immunogold particles. Small change in the marker concentration results in a significant variation in the staining efficiency when other variables are kept constant. The effect of temperature is always accompanied with that of the medium viscosity. There is a linear relationship between the degree of labeling and the temperature when the viscosity effect is combined. The staining of fibrinogen molecules adsorbed on the polyethylene surface at three different temperatures shows a temperature dependence which is in close agreement with the theory. The degree of labeling is inversely related to a square root of the size of gold markers. This analysis makes it possible to maximize the staining sensitivity and to improve the reproducibility of the labeling. Thus, the immunogold staining under a well defined condition allows quantification as well as positive identification and localization of target proteins. This technique has been used to study protein adsorption on biomaterials.

The effect of fibrinogen sialic acid residues on ex vivo platelet deposition on biomaterials

The effect of fibrinogen sialic acid residues on platelet deposition onto polymer surfaces was examined using a canine ex vivo shunt model. To test the hypothesis that desialylated fibrinogen may enhance platelet deposition when precoated on biomaterials, canine fibrinogen was desialylated and precoated on polyvinyl chloride (PVC) shunts. When protein-coated PVC shunts were exposed to flowing whole blood, both the native and the desialylated fibrinogen elicited the same profile of platelet deposition. This study indicates that platelet deposition and thrombus formation on biomaterial surfaces is not mediated by a mechanism which involves the sialic acid residues of fibrinogen.

Human leukocyte antigen (HLA) in Korean patients with autoimmune thyroid diseases

In previous studies, there has been evidence of different allelic associations with a particular disease among various ethnic groups. The present study was done to investigate the associations between HLA and autoimmune thyroid diseases in the Korean. We found no association between Graves’ disease and HLA-B8 or -B35. However, increased frequencies of HLA-A11 and -DRw8, and the decreased frequencies of HLA-A10 and B12 were found in patients with Graves’ disease. In the cases of Hashimoto’s disease, the frequencies of HLA-A2 and -DRw8 were found to be significantly increased and the frequency of HLA-DRw6y decreased. These data indicate that the association between autoimmune thyroid disease and HLA in the Korean would appear to be different from that in most other racial groups, including Caucasians, Japanese and Chinese.

Acute surface-induced thrombosis in the canine ex vivo model: importance of protein composition of the initial monolayer and platelet activation

The initial events occurring at the blood-polymer interface were examined using a canine ex vivo arteriovenous shunt model. Thrombogenic (fibrinogen) and nonthrombogenic (albumin) proteins were preadsorbed on poly(vinyl chloride), polyethylene, and silicone rubber shunt surfaces, and the blood responses were analyzed using the platelet deposition profile as an indicator of surface thrombogenicity. The distributions of preadsorbed protein molecules on the various polymer surfaces were studied using an immunogold bead (colloidal gold particles coated with antibodies) staining technique and shown to be homogeneous. A sequential protein adsorption technique was developed to probe the nature of competitive protein adsorption and to observe the effect of surface protein concentration on thrombogenicity. The thrombogenicity of a surface was determined by the composition of the initial protein layer rather than the total concentration of protein on the polymer surfaces. The composition of this layer determines the extent of platelet activation and the adhesive strength between platelets and the polymer surface.