Relationship between the Decrease of Cytotoxic Antibody with the Elapse of Time and Hyperacute Rejection in Hyperimmunized Rats

Preformed cytotoxic antibody which causes hyperacute rejection is formed on gestation, blood transfusion and infection. It is an important problem whether or not transplantation is possible in the recipients sensitized like this. We studied the decrease of preformed cytotoxic antibody with the elapse of time in sensitized recipients and its influence on graft survival time, using inbred rats. Inbred ACI rats and Fischer rats were used as experimental models. Hyperimmunized Fischer rat recipients were prepared by skin grafting and spleen lymphoid cell booster. In order to observe the course of decrease or disappearance of the antibody after sensitization, anti T cell warm cytotoxic antibody (CA-TW) was assayed in rat groups which were hyperimmunized one week, one, three and six months before, respectively. The hearts of ACI rats were transplanted to the groups of hyperimmunized Fischer rat recipients to study the relationship between graft survival time and cytotoxic antibody. 1. Controls: The heart of ACI rat transplanted to nontreated Fischer recipient showed graft survival time of 8.1 ± 1.4 days. 2. Group of rats hyperimmunized one week before: The transplanted ACI heart was hyperacutely rejected 0.55 ± 0.38 hr after grafting in all recipients. 3. Group of rats hyperimmunized one month before: The transplanted ACI heart was hyperacutely rejected in five of the 12 recipients. The graft survival time was 17.2 ± 9.2 hr. 4. Group of rats hyperimmunized three months before: Hyperacute rejection was observed in three of the 12 recipients. The graft survival time was 43.0 ± 28.1 hr. 5. Group of rats hyperimmunized six months before: Hyperacute rejection was not observed. The graft survival time of the transplanted heart was 96.0 ± 37.5 hr. The pattern of rejection varied from accelerate to acute rejection. 6. Spontaneous decrease of preformed cytotoxic antibody after hyperimmunization: Fischer rats were hyperimmunized by skin grafting from ACI rat and five booster shots of spleen lymphoid cell. The change of their antibody titer was examined. CA-TW of the groups hyperimmunized three and six months before, respectively were significantly lower than that for the group hyperimmunized one week before the transplantation. 7. Relationship between preformed cytotoxic antibody titer and graft survival time of transplanted heart: There was a negative correlation between CA-TW titer and graft survival time; r = —0.7274. To sum up, cytotoxic antibody generated by hyperimmunization was decreased with the passage of time. It was thought that the decrease of CA-TW closely related to graft survival time. It was revealed that hyperacute rejection no longer occurred after a lapse of six months after sensitization and that the graft was taken for more than 90 hr and then rejected either by accelerate or by acute rejection

Studies on the Control of Hyperacute Rejection in Hyperimmunized Rat: Combination of Donor Specific Blood Transfusion (DST) and Immunosuppressive Drugs

In order to decrease preformed cytotoxic antibodies, which are the main cause of hyper-acute rejection, donor specific blood transfusion (hereafter designated as DST) was performed. Immunosuppressants were administered at the same time to examine whether the combined treatment with DST can inhibit rapid reproduction of antibodies in the serum of a sensitized recipient. Hyper immunized Fischer rat recipients were used as experimental models. Blood of ACI rat was transfused to the recipients as DST. Beta-methosone and Anti-lymphocyte serum (hereafter designated as ALS) were given as immuno suppressive drugs combined with DST. The heart of ACI rat was transplanted to the hyperimmunized Fischer recipent treated as described above. The cardiac graft survival time was observed and the change in cytotoxic antibody titer of the recipient was determined with the elapse of time. Performed cytotoxic antibodies formed by hyperimmunization were adsorbed or diminished, by DST, and the heart graft survivied for about 54 hr in the group treated with DST, while it was hyperacutely rejected after about 0.4 hr in controls. However, DST was effective only when it was performed once. Transfusion after that acted as a booster, inducing reproduction of anti T-cell warm cytotoxic antibody (CA-TW). Therefore repeated transfusion was thought to be contraindication. Beta-methasone or ALS were administered after adsorption of antibodies by DST in order to prevent antibodies from being rapidly formed again in the serum of a sensitized recipient. The suppressive effect was greatest in the group treated with combination of DST and ALS, and the heart graft survivied for 94 hr. In this group, the pattern of rejection was not hyperacute rejection but acute to accerelated one. It wa revealed that hyperacute rejection can be depressed to some extent

Avaliação multiparamétrica por ressonância magnética e correlação com testes neuropsicológicos em pacientes com epilepsia do lobo temporal

Orientador: Prof. Dr. Carlos Eduardo Soares SilvadoCoorientador: Prof. Dr. Arnolfo de Carvalho NetoColaboradora: Dra. Maria Joana Mader-JoaquimTese (doutorado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Medicina Interna e Ciências da Saúde. Defesa : Curitiba, 27/10/2021Inclui referênciasResumo: Objetivo: Determinar se medidas de volume hipocampal total ou de seus segmentos internos (subfields), obtidos de processamentos de exames de ressonância magnética, tem associação com testes neuropsicológicos de memória episódica, verbal e não verbal, analisando pacientes com epilepsia do lobo temporal com atrofia hipocampal unilateral. Os testes neuropsicológicos podem inferir a lateralização da área epileptogênica, associando a memória verbal a estruturas mesiais do lobo temporal esquerdo e a memória visual ou não verbal com o lado direito. A hipótese testada é que existe correlação entre as volumetrias hipocampal total e de seus segmentos internos e o desempenho em testes neuropsicológicos. Método: Os pacientes selecionados apresentavam síndrome de epilepsia do lobo temporal mesial refratária ao tratamento medicamentoso, com atrofia hipocampal unilateral com zona de início ictal homolateral definida na videoeletroencefalografia. Foram adquiridas imagens de ressonância magnética em aparelho de alto campo de 3 teslas utilizando protocolo de alta resolução e processadas com o software FreeSurfer. A memória verbal foi avaliada usando o Teste de Aprendizagem Auditivo- Verbal de Rey e os testes de memória visual empregaram o Teste da Figura Complexa de Rey-Osterrieth. Na primeira fase do estudo foram analisados volumes hipocampais totais de 35 pacientes (15 com atrofia hipocampal esquerda), extraídos com a versão 6.0 do software, e foram considerados os resultados das evocações tardias dos testes neuropsicológicos. Na segunda fase do estudo foram analisados os volumes dos segmentos internos (subfields) Cornu Ammonis (CA)1, CA2/3 e CA4 de uma amostra ampliada com 62 pacientes (29 com atrofia hipocampal esquerda), extraídos com a versão 7.1 do software, e foram analisadas as memórias de curto prazo e as evocações imediata e tardia. Na análise estatística foram considerados os índices de assimetria entre os volumes direito e esquerdo, tanto na análise de volume total do hipocampo quanto na análise de volumes dos segmentos internos. Foram estudadas as relações entre estes índices de assimetria do hipocampo (primeira fase do estudo) e dos segmentos internos (segunda fase) e o desempenho nos testes de memória. Resultados: Primeira fase (volumetria hipocampal total): foram observados déficits na memória verbal e visual em pacientes com redução de volume tanto no hipocampo esquerdo quanto no direito. Os pacientes com redução do volume do hipocampo esquerdo apresentaram desempenho inferior nos testes de memória verbal em comparação com aqueles com atrofia do hipocampo direito (t = -3,813, p <0,001). Em relação aos déficits de memória visual não foi observado diferença estatisticamente significativa (t = 0,074, p = 0,942). A correlação entre o Índice de assimetria dos hipocampos e os escores Z das evocações tardias verbais e visuais foi significativo apenas para o escore Z visual na epilepsia do lobo temporal no lado direito (R = - 0,45, p = 0,048). Segunda fase (volumetria dos segmentos internos do hipocampo): em relação aos segmentos internos, observou-se moderada correlação do segmento CA2/3 com o desempenho na memória visual tanto para a atrofia hipocampal direita quanto esquerda, sem distinção entre evocação imediata ou tardia. Observou-se moderada correlação do segmento CA4 com a memória visual em pacientes com atrofia hipocampal direita. Não foram observadas associações com o segmento CA1. Conclusões: Apesar dos pacientes com atrofia hipocampal esquerda apresentarem resultados inferiores nos testes de memória verbal comparado a pacientes com atrofia hipocampal direita, não há correlação entre a perda volumétrica e o desempenho nestes testes. Por outro lado, apesar de não haver diferença estatística significativa nos testes de memória visual entre pacientes com atrofia hipocampal direita e esquerda, alguns volumes hipocampais apresentam correlação nos testes de memória visual, mais evidente na atrofia hipocampal direita. Os resultados mostram que podem ser observadas correlações entre medidas volumétricas e testes neuropsicológicos. As limitações observadas no estudo devem ser consideradas com cautela, recomendando-se estudos adicionais com aprimoramentos nos protocolos de imagem e correlações histopatológicas para a validação em uso clínico.Abstract: Objective: To determine whether measurements of total hippocampal volume or its internal segments (subfields), obtained from the processing of MRI scans, are associated with neuropsychological tests of episodic, verbal, and non-verbal memory, analyzing patients with temporal lobe epilepsy with unilateral hippocampal atrophy. Neuropsychological tests can infer the lateralization of the epileptogenic area, associating verbal memory with mesial structures of the left temporal lobe and visual or non-verbal memory with the right side. The hypothesis tested is a correlation between total hippocampal volumetry and its internal segments and performance in neuropsychological tests. Method: The selected patients had mesial temporal lobe epilepsy syndrome refractory to drug treatment, with unilateral hippocampal atrophy and homolateral ictal onset zone defined on video electroencephalography. Magnetic resonance images were acquired in a 3-tesla high-field scanner using a high-resolution protocol and processed with FreeSurfer software. Verbal memory was assessed using the Rey Auditory-Verbal Learning Test, and the visual memory tests employed the Rey-Osterrieth Complex Figure Test. In the first phase of the study, total hippocampal volumes of 35 patients (15 with left hippocampal atrophy) were analyzed, extracted with software version 6.0, and the results of late recall of neuropsychological tests were considered. In the second phase of the study, the volumes of the internal segments (subfields) Cornu Ammonis (CA)1, CA2/3, and CA4 of a sample of 62 patients (29 with left hippocampal atrophy), extracted with the software version 7.1, were correlated to short-term memory and immediate and late recalls. The statistical analysis considered the asymmetry indices between the right and left volumes, both in the analysis of the total volume of the hippocampus and in the analysis of the volumes of the internal segments. The relationships between the asymmetry indices of the total volume of the hippocampus (first phase of the study) and internal segments (second phase) and performance in memory tests were studied. Results: First phase (total hippocampal volumetry): deficits in verbal and visual memory were observed in patients with volume reduction in both the left and right hippocampi. Patients with reduced left hippocampal volume performed poorly on verbal memory tests compared with those with right hippocampal atrophy (t = -3.813, p <0.001). Regarding visual memory deficits, no statistically significant difference was observed (t = 0.074, p = 0.942). The correlation between the Hippocampal Asymmetry Index and the Z-scores of late verbal and visual recalls was significant only for the visual Z-score in right-sided temporal lobe epilepsy (R = -0.45, p = 0.048). Second phase (volumetry of the internal segments of the hippocampus): considering the inner segments, there was a moderate correlation of the CA2/3 segment with performance in visual memory for both right and left hippocampal atrophy, with no distinction between immediate and late recall. A moderate correlation of the CA4 segment with visual memory was observed in patients with right hippocampal atrophy. No associations with the CA1 segment were observed. Conclusions: Although patients with left hippocampal atrophy had worse results in verbal memory tests compared to patients with right hippocampal atrophy, there is no correlation between volume loss and performance in these tests. On the other hand, although there is no statistically significant difference in the visual memory tests between patients with right and left hippocampal atrophy, some hippocampal volumes show a correlation with visual memory tests, more evident in the right hippocampal atrophy. The results show that correlations between volumetric measurements and neuropsychological tests can be observed. The limitations observed in the study should be considered with caution, recommending additional studies with improvements in imaging protocols and histopathological correlations for validation in clinical use

Discotic liquid crystals of transition metal complexes 50(dagger): spiranthes-like supramolecular structure of phthalocyanine-fullerene dyads

We have synthesized novel liquid crystalline Pc-C-60 dyads (CnS)(6)PcCu-C-60 (n = 14, 16, 18: 1a-1c) by using our developed synthetic method in order to investigate the mesomorphism and alignment behavior. Each of the (CnS)(6)PcCu-C-60 dyads shows perfect homeotropic alignment in the Col(ho) mesophase between two glass plates for n = 14, 16, 18 and also on a glass plate for n = 14, although none of the parent Pc compounds (CnS)(8)PcCu and the Pc precursors (CnS)(6)PcCu-OH and (CnS)(6)PcCu-OFBA shows homeotropic alignment. It may be attributed to the strong affinity between fullerene and glass surface. Although the reason is not so clear at the present time, this is very useful guideline for the molecular design to prepare homeotropic alignment-showing discotic liquid crystals. Very interestingly, the spherical C-60 parts form a helical structure around the column formed by the disk-like Pc parts. This supramolecular structure very resembles spiranthes. The spiranthes-like supramolecular structure is compatible with one-dimensional nano-array expecting the high conversion efficiency of solar cells.ArticleJOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 18(5):366-379 (2014)journal articl

Ⅴ. Application and other cases

富山大学名城大学Editor : Tazaki, Kazue |田崎, 和

Approximation Algorithms for the Longest Run Subsequence Problem

We study the approximability of the Longest Run Subsequence problem (LRS for short). For a string S = s_1 ? s_n over an alphabet ?, a run of a symbol ? ? ? in S is a maximal substring of consecutive occurrences of ?. A run subsequence S\u27 of S is a sequence in which every symbol ? ? ? occurs in at most one run. Given a string S, the goal of LRS is to find a longest run subsequence S^* of S such that the length |S^*| is maximized over all the run subsequences of S. It is known that LRS is APX-hard even if each symbol has at most two occurrences in the input string, and that LRS admits a polynomial-time k-approximation algorithm if the number of occurrences of every symbol in the input string is bounded by k. In this paper, we design a polynomial-time (k+1)/2-approximation algorithm for LRS under the k-occurrence constraint on input strings. For the case k = 2, we further improve the approximation ratio from 3/2 to 4/3

Proton inelastic scattering to continuum studied with antisymmetrized molecular dynamics

Intermediate energy (p,p$'$x) reaction is studied with antisymmetrized molecular dynamics (AMD) in the cases of $^{58}$Ni target with $E_p = 120$ MeV and $^{12}$C target with $E_p =$ 200 and 90 MeV. Angular distributions for various $E_{p'}$ energies are shown to be reproduced well without any adjustable parameter, which shows the reliability and usefulness of AMD in describing light-ion reactions. Detailed analyses of the calculations are made in the case of $^{58}$Ni target and following results are obtained: Two-step contributions are found to be dominant in some large angle region and to be indispensable for the reproduction of data. Furthermore the reproduction of data in the large angle region \theta \agt 120^\circ for $E_{p'}$ = 100 MeV is shown to be due to three-step contributions. Angular distributions for E_{p'} \agt 40 MeV are found to be insensitive to the choice of different in-medium nucleon-nucleon cross sections $\sigma_{NN}$ and the reason of this insensitivity is discussed in detail. On the other hand, the total reaction cross section and the cross section of evaporated protons are found to be sensitive to $\sigma_{NN}$. In the course of the analyses of the calculations, comparison is made with the distorted wave approach.Comment: 16 pages, 7 Postscript figure