Effect of the angiotensin-converting enzyme inhibitor enalapril on post-transplant erythrocytosis

Post-transplant erythrocytosis (PTE) is increasingly recognized as a complication of kidney transplantation. In this study we report the effect of the angiotesin-converting enzyme (ACE) inhibitor enalapril on hematocrit (Ht) and erythropoietin in four patients with PTE. Four renal allograft recipients with Ht greater than 51% were studied. Treatment was initiated with enalapril administered orally at a dose of 2.5 mg/day. All the patients had an increase of hemoglobin (Hb) (17.7 +/- 0.64 g/dl), Ht (54.5 +/- 1.29%) and red blood cell count (RBC) (584 +/- 19.2 x 10(4)/microliter). All patients responded to enalapril in 8 weeks with a significant decrease of Hb, Ht, and RBC. In one patient, the downward trend was more rapid and sustained, and treatment had to be discontinued to prevent the development of anemia. Serum erythropoietin showed normal in all four patients and remained unchanged during the study, even after discontinuation of enalapril treatment. Serum creatinine remained relatively stable throughout the study. These results suggest that PTE may not be dependent upon circulating erythropoietin and that enalapril treatment may be an effective treatment of PTE without renal dysfunction.

[Multicentric Castleman's disease with lymphoid interstitial pneumonia and polyneuropathy]

A 51-year-old woman was admitted to a local hospital because of pneumonia, and received a diagnosis of cervical lymphadenopathy, anemia, and hyperimmunoglobulinemia with suspected multicentric Castleman's disease (MCD). At the age of 53 she was transferred to our hospital because of numbness and muscle weakness. Polyclonal hyperimmunoglobulinemia was observed, and biopsy specimens of lymph node tissue revealed infiltration of plasma cells in the interfollicular areas, thus leading to a diagnosis of MCD. A chest computed tomography scan revealed diffuse nodular shadows in all lung fields, and a transbronchial lung biopsy disclosed infiltration of plasma cells in the alveolar septa. Together, these findings indicated lymphoid interstitial pneumonia (LIP). Polyneuropathy was diagnosed by neurological examination and nerve conduction studies. Treatment with prednisolone and cyclophosphamide was ineffective against LIP probably because the patient had coexising pulmonary fibrosis. Since pulmonary complications of MCD determine its prognosis, their early detection and treatment are essential.

Expression of bcl-2 homologue mRNAs in rat liver allograft: rejection-induced cell apoptosis is associated with upregulation of bax and bcl-xs expression

Apoptosis is considered to play an important role in rejection of organ transplants, although the precise mechanism has not been elucidated. In this study, we screened for the expression of bcl-2 homologues (bcl-2, bax, bcl-xl, and bcl-xs) and Fas ligand (FasL) by RT-PCR method in grafts during acute rejection in rats following liver transplantation. Both bax and bcl-xs (inducers of apoptosis) mRNA levels increased steadily in the allografted group from postoperative day (POD) 2 to 8, while no remarkable changes of bcl-2 and bcl-xl expression (inhibitors of apoptosis) were recognized. Significant induction of FasL gene expression was observed in the allografted group on POD 4 and expression gradually decreased thereafter, although minimal FasL mRNA expression was seen in isografts. Our results indicated, for the first time, that rejection-induced cell apoptosis is closely associated with upregulation of bax and bcl-xs expression besides FasL, but not with down-regulation of bcl-xl.

Effect of FTY720 on immunoregulation in concordant xenotransplantation

The present study was designed to analyze the immunosuppressive activity of FTY720 in concordant xenotransplantation. When T and B lymphocytes of human peripheral blood were incubated with FTY720, the number of viable cells decreased in a dose-dependent manner at doses higher than 4 x 10(-5) M. DNA fragmentation was observed at doses higher than 1 x 10(-5) M in T cell-rich fractions and at doses higher than 4 x 10(-5) M in B cell-rich fractions. These data demonstrate that FTY720 is cytotoxic to B lymphocytes as well as T lymphocytes and apoptosis may play an important role in this cytotoxicity. Golden Syrian hamsters were the donors and Lewis rats the recipients of skin grafts. The recipients were divided into the following four groups: (1) untreated recipients, (2) FTY720 (5 mg/kg per day) was administered orally for 8 days (days-1-6), (3) FK506 (1 mg/kg per day) was injected i.m. for 7 days (days 0-6), and (4) FK506 (1 mg/kg per day) was injected i.m. for 7 days (days 0-6) and FTY720 (5 mg/kg per day) was administered orally for 8 days (days-1-6). The mean graft survival times in groups 1-4 were 9.7 +/- 0.52 days (n = 6), 12.0 +/- 0.71 days (n = 6), 13.2 +/- 1.6 days (n = 6), and 37.7 +/- 4.3 days (n = 6), respectively. There was a significant difference in the mean survival time between groups one and four. Combined therapy with FTY720 and FK506 is a useful tool for immunoregulation in xenotransplantation.

Recurrent excitation of motoneurons in the isolated spinal cord of newborn rats detected by whole-cell recording

Motoneurons in the isolated spinal cord of newborn rats (1- to 6-day-old) were visualized using infrared videomicroscopy. Whole-cell recordings were performed from the neurons under observation. Stimulation of a sciatic nerve which adjoined ventral roots elicited postsynaptic currents (PSCs) in 28 out of 88 motoneurons. When membrane potentials were changed, some PSCs reversed at around -70 mV, which was compatible with the chloride equilibrium potential calculated. Thus, they were considered to be recurrent inhibitory, namely Renshaw inhibition. On the other hand, we detected PSCs which reversed at +3.3 mV on average. They were interpreted as excitatory based on the level of the reversal potential which was similar to that of orthodromic excitatory PSCs. To determine the origin of the antidromic excitatory inputs, the effect of d-tubocurarine (10 microM) on the PSCs was examined. In three out of five motoneurons, the excitatory currents were eliminated. Therefore, it was concluded that the excitatory inputs, if not all, are mediated via the axon collaterals. Furthermore, it was found that the locations of motoneurons receiving the recurrent inhibitory and the excitatory PSCs were different in the spinal cord.

H-7-induced apoptosis in the cells of a Drosophila neuronal cell line through affecting unidentified H-7-sensitive substance(s)

The present study was undertaken to reveal underlying mechanisms of apoptosis in neurons using clonal neuronal cells, ML-DmBG2-c2, derived from Drosophila larval central nervous system 1-(5-Isoquinolinesulfonyl)-2-methylpiperazine (H-7), a protein kinase inhibitor, induced cell death with typical features of apoptosis such as internucleosomal DNA fragmentation, nuclear condensation and apoptotic bodies in the cells. Though H-7 is known to inhibit cAMP-dependent protein kinase (PKA), protein kinase C (PKC), cGMP-dependent protein kinase (PKG), myosin light chain kinase (MLCK), and casein kinase I (CKI), specific inhibitors for these kinases such as H-89, calphostin C, ML-9, or CKI-7 did not induce apoptosis in the cells. Other kinases such as tyrosine kinase. PI3-kinase and Ca2+/CaM kinase II so far examined in the present study were interpreted not to be involved in the apoptotic cascade. Therefore, it is concluded that an H-7-sensitive substance(s) other than these kinases is responsible for the apoptosis in the neuronal cells. Caspase inhibitors prevented apoptosis in the cells treated with H-7. These results suggest that caspase(s) is involved downstream of the H-7-sensitive point in the cascade of the apoptosis.

[Memory function in aging and Parkinson's disease--an event-related potential study]

The N400 of event-related potentials (ERPs) was recorded in 17 healthy young subjects (mean age 24.4 years), 14 healthy old subjects (healthy control subjects, mean age 62.7 years), and 21 patients with nondemented Parkinson's disease (PD, mean age, 63.8 years) as they listened to words or nonwords. Some words were repeated immediately after the initial presentation (2 sec), while others were repeated after 5 intervening words (12 sec) or after 2 to 4 minutes. The subjects were required to respond to occasional nonwords. Rey's auditory verbal learning test(AVLT) was also performed. The mean N400 amplitude was smaller in patients with PD than in either healthy group, but there was no difference between the two healthy groups. In the young subjects, N400 was attenuated for repeated words, and the attenuation was more pronounced for immediate than for delayed repetitions. N400 attenuation in the old subjects was more markedly reduced as the interval between the 1st and 2nd presentation increased than in the young subjects. In PD patients, attenuation was noted only for immediate repetition. Free recall by the old subjects was impaired relative to the young subjects throughout the AVLT trials, and was even more impaired in patients with PD. In addition, the number of free recalls increased less with the number of trials in patients with PD than in the old subjects. These results may indicate that episodic memory declines with advancing age, and declines even more in patients with PD. In addition, the ability to transform information form short-term memory to long-term memory appear to be impaired in patients with PD.

Antimutagenic structural modification of quinoline assessed by an in vivo mutagenesis assay using lacZ-transgenic mice

Quinoline, a hepatocarcinogen, mutates the bacterial tester strains in the presence of the rat liver microsomal enzymes and induces GST-P (placental glutathione S-transferase)-positive foci in a medium-term bioassay system for hepatocarcinogenesis. On the other hand, 3-fluorinated quinoline was neither mutagenic nor carcinogenic in the same assay systems, whereas, 5-fluoroquinoline was mutagenic and carcinogenic. Quinoline was recently demonstrated to be mutagenic in an in vivo mutagenicity assay system using the lacZ-transgenic mouse (MutaMouse). The present study was undertaken to know whether 3-fluoroquinoline would be devoid of in vivo mutagenicity in MutaMouse. Quinoline and 5-fluoroquinoline were also tested in the same system. Mutagenicity was evaluated in the liver, the target organ of quinoline carcinogenesis, and also in the bone marrow and testis. The results strongly indicate that fluorine-substitution at the position-3 of quinoline could be an anti-genotoxic structural modification of quinoline in a wide range of its genotoxic end-points.

Relationship of xenogeneic microchimerism to graft outcome in hamster-to-rat lung xenotransplantation

BACKGROUND

In spite of the progress in allogeneic microchimerism research, few reports have dealt with the biologic relevance of xenogeneic microchimerism after organ xenotransplantation. These experiments were designed to analyze the development of xenogeneic microchimerism and its relationship to graft outcome in hamster-to-rat lung xenotransplantation.

METHODS

Golden Syrian hamsters were the donors and Lewis rats the recipients of xenogeneic lung transplantation. Animals were divided into three groups: group 1 were untreated; group 2 received cyclophosphamide (10 mg/kg/day for 6 days) and a short course of FK506 (2 mg/kg/day for 8 days); and group 3 were treated with cyclophosphamide and a long course of FK506 (2 mg/kg/day for 8 days, 1 mg/kg/day for 23 days, and then 0.5 mg/kg/day continuously). Xenogeneic microchimerisms were evaluated by use of polymerase chain reaction with primers specific for the hamster hypoxanthine phosphoribosyl-transferase gene.

RESULTS

The median graft survival times for groups 1, 2, and 3 were 3 days (n = 6), 22 days (n = 7), and 96.5 days (n = 6), respectively. In groups 1 and 2, the incidence of microchimerisms declined in parallel with the progression of rejection. In group 3, it changed dynamically, initially declining, then progressively increasing and finally disappearing.

CONCLUSIONS

In the short-term graft survivors, xenogeneic microchimerism in the peripheral blood was closely related to graft outcome. However, it showed dynamic changes and finally disappeared in long-term graft survivors, and the incidence of microchimerism at a single time point did not reflect the donor-recipient immunologic status.

In vivo mutagenesis by the hepatocarcinogen quinoline in the lacZ transgenic mouse: evidence for its in vivo genotoxicity

Quinoline is carcinogenic to the liver of rats and mice and mutagenic to bacterial tester strains in the presence of rat liver microsomal enzymes. The unscheduled DNA synthesis (UDS) study suggested that quinoline might be a non-genotoxic carcinogen because of the lack of UDS-inducing capacity. In order to determine whether or not cancer induction is initiated by mutagenic DNA lesions, the present study was undertaken to evaluate the mutagenicity of quinoline in an in vivo mutation assay system using the lac Z transgenic mouse (Muta Mouse). Mutation was only induced in the liver, the target organ of carcinogenesis by quinoline, but not in the other organs examined, i.e. lung, kidney and spleen. Mutant frequency in the liver was 4-fold higher than in the untreated control animals. Dimethylnitrosamine, used as a positive control, induced mutation at a frequency 5-fold higher in the liver and 3-fold higher in the spleen than in their respective control organs. It can be concluded that the genotoxicity of quinoline is responsible for its hepatocarcinogenesis, although UDS was not induced under the conditions previously reported.

Phosphorylation of the immunosuppressant FK506-binding protein FKBP52 by casein kinase II: regulation of HSP90-binding activity of FKBP52

FKBP52 (HSP56, p59, HBI) is the 59-kDa immunosuppressant FK506-binding protein and has peptidyl prolyl isomerase as well as a chaperone-like activity in vitro. FKBP52 associates with the heat shock protein HSP90 and is included in the steroid hormone receptor complexes in vivo. FKBP52 possesses a well conserved phosphorylation site for casein kinase II (CK2) that was previously shown to be associated with HSP90. Here we examined whether FKBP52 is phosphorylated by CK2 both in vivo and in vitro. Recombinant rabbit FKBP52 was phosphorylated by purified CK2. We expressed and purified deletion mutants of FKBP52 to determine the site(s) phosphorylated by CK2. Thr-143 in the hinge I region was identified as the major phosphorylation site for CK2. A synthetic peptide corresponding to this region was phosphorylated by CK2, and the peptide competitively inhibited the phosphorylation of other substrates by CK2. The [32P]phosphate labeling of FKBP52-expressing cells revealed that the same site is also phosphorylated in vivo. FK506 binding to FKBP52 did not affect the phosphorylation by CK2 and, conversely, the FK506-binding activity of FKBP52 was not affected by the phosphorylation. Most importantly, CK2-phosphorylated FKBP52 did not bind to HSP90. These results indicate that CK2 phosphorylates FKBP52 both in vitro and in vivo and thus may regulate the protein composition of chaperone-containing complexes such as those of steroid receptors and certain protein kinases.

[Pulmonary metastasis after resection of non-invasive thymoma: a case report--analysis of nuclear DNA pattern and pathological findings]

After resection of a non-invasive thymoma, two metastatic lung tumors were found in the left upper lobe and the left lower lobe. There were differences in tumor doubling time (TDT) and invasion between the metastatic tumor in the lower lobe and the one in the upper lobe. The TDTs of the tumors were 834.1 days and 328.3 days, and the tumor of the left lower lobe invaded the left lateral basal segmental bronchus (B9). The differences in the two tumors were determined by pathological findings and nuclear DNA pattern. Pathologically, the resected thymoma and both of the metastatic tumors were mixed type, which consisted of epithelial cells and lymphocytes. But by epithelium form, the resected thymoma and the tumor in the lower lobe were classified as cortex type, and only the slow growing tumor in the upper lobe contained a spindle-cell component. The DNA pattern of the resected thymoma was aneuploid and the two metastatic tumors were diploid. As this case is very interesting clinically and pathologically, we reported it.

Near-infrared spectroscopic method for assessing the tissue oxygenation state of living lung

To quantify changes in tissue oxygenation of pathologic lungs, we applied a novel method using near-infrared spectroscopy (NIRs). In in vitro experiments, we assayed the effect of photon scattering on the absorption spectra of an in vitro system simulating structures of lung, which consists of test tube containing air in hematocrit tubes and red blood cell suspension with various predetermined hemoglobin concentrations. It was determined that photon scattering of the tissue containing air did not affect the absorption in the NIR region. In in vivo experiments, we tested the applicability of the NIRs technique in rat lungs under the following conditions: (1) hypoxic loading; (2) administration of an inhibitor (NaCN) of the mitochondrial respiratory chain; (3) hemorrhagic shock. We found that: (1) Changes in hemoglobin oxygenation state in the lung measured by NIRs depended on inspired oxygen concentrations; (2) NaCN-induced reduction of cytochrome oxidase a,a3 in the lung was observed; and (3) Total hemoglobin levels in the lung decreased after bleeding. Changes in the hemoglobin oxygenation state and cytochrome oxidase redox state in the lung were determined using the least-square-curve fitting for NIR absorption spectra. Our NIRs technique was capable of assessing the hemoglobin oxygenation and cytochrome oxidase redox state in the lung.

Characterization of the rpsL and rrs genes of streptomycin-resistant clinical isolates of Mycobacterium tuberculosis in Japan

Mutations in the rpsL and rrs genes associated with streptomycin resistance in Mycobacterium tuberculosis clinically isolated in Japan were characterized. The rpsL genes of 172 clinical isolates were amplified by PCR and classified into two groups on the basis of MboII restriction digestion. Thirty-three out of 54 (61.1%) streptomycin-highly resistant isolates (MIC > 200 micrograms ml-1) were not digested by MboII. By contrast, the remaining 21 of 54 (38.9%) streptomycin-highly resistant isolates, all of 41 isolates with streptomycin resistance at a lower level (20 micrograms ml-1 < MIC < or = 200 micrograms ml-1), and all of 77 streptomycin-sensitive isolates, were restricted. Thus, all isolates resistant for MboII digestion showed a high level of resistance to streptomycin. Subsequently, the sequence for the rpsL and rrs genes from the 46 isolates were analysed. Eighteen out of 19 (94.7%) streptomycin-highly resistant isolates carried a mutation in any rpsL gene at position 43 or 88, or the rrs gene; 10 out of 17 (58.8%) streptomycin-resistant isolates at a lower level were confirmed to exhibit the mutation of either the mutated rpsL gene at position 88, or the rrs gene. In the total 36 streptomycin-resistant isolates, the mutation of the rpsL or rrs gene was observed in 28 streptomycin-resistant isolates, corresponding to 77.8%, whereas none of the streptomycin-sensitive isolates had mutations in either the rpsL or rrs gene.

Allelic variants of the human MHC class I chain-related B gene (MICB)

The human major histocompatibility complex (MHC) is located within a 4 megabase segment on chromosome 6p21.3. Recently, a highly divergent MHC class I chain-related gene family, MIC was identified within the class I region. The MICA and MICB genes in this family have unique patterns of tissue expression. The MICA gene is highly polymorphic, with more than 20 alleles identified to date. To elucidate the extent of MICB allelic variations, we sequenced exons 2 (alpha 1), 3 (alpha 2), 4 (alpha 3), and 5 (transmembrane) as well as introns 2 and 4 of this gene in 46 HLA homozygous B-cell lines. We report the identification of eleven alleles based on seven non-synonymous, two synonymous, and four intronic nucleotide variations. Interestingly, one allele has a nonsense mutation resulting in a premature termination codon in the alpha 2 domain. Thus, MICB appears to have fewer alleles than MICA, not unlike the allelic ratio between the HLA-C and -B loci. A preliminary linkage analysis of the MICB alleles with those of the closely located MICA and HLA-B genes revealed no conspicuous linkage disequilibrium between them, implying the presence of a potential recombination hotspot between the MICB and MICA genes.

[Interstitial pneumonia associated with human adjuvant disease which developed 30 years after silicone augmentation mammoplasty]

A 51-year-old woman was admitted to our hospital with exertional dyspnea, swelling and stiffness in her fingers. Raynaud's phenomenon and mammary and axillary lymphadenopathy. She had received silicone augmentation mammoplasty 30 years ago, and had since noticed bilateral mammary and axillary lymphadenopathy that was stable in size. In the 2 years before admittance she had become aware of an exacerbation of the lymphadenopathy had begun to experience and exertional dyspnea several months before admission suggesting a connective tissue disease. Physical examination revealed symmetrical weakness of the proximal limb muscles and fine crackles in the base of both lungs. Elevated myogenic enzymes, inflammatory reactions, and positive anti-SSA antibody were noted. Based upon these findings, muscle and lip biopsy results, myogenic EMG, and an apple tree appearance on sialography, a differential diagnosis of polymypositis or sjögren's syndrome was made. Axillary lymph node biopsy findings were consistent with silicone lymphadenitis. In addition, chest roentgenogram and HRCT (which revealed decreased lung volumes and interstitial opacities with no honeycombing, present predominatly in the subpleural space), pulmonary function tests (decreased VC and DLco), bronchoalveolar lavage (elevated total cell count and neutrophil and eosinophil fractions), and transbronchial lung biopsy specimens (unevently distributed alveolitis with fibrosis) indicated concurrent interstitial pneumonia. The clinical correlation between exacerbation of silicone lymphadenopathy and the development of connective tissue disease with accompanying interstitial pneumonia strongly suggested human adjuvant disease (HAD) as the pathogenesis. To our knowledge, interstitial pneumonia associated with HAD is rare.