[A case of Tsutsugamushi disease infected by mountain climbing in the Republic of Korea]

A 47-year-old male was infected with Tsutsugamushi disease showing typical findings after mountain climbing in the Republic of Korea (ROK). Immunoserological examinations suggested that he had been infected in ROK. In this case, detection of the characteristic sting was useful for early diagnosis and treatment. Until now, Tsusugamushi disease has not been reported in Hokkaido. It is the first case registered in Hokkaido. With extensive international intercourse these days, this case suggests that Tsutsugamushi disease can occur potentially all over Japan.

Analysis of expression of the melanoma-associated antigens MART-1 and gp100 in metastatic melanoma cell lines and in in situ lesions

MART-1 and gp100 melanoma associated antigens (MAA) are expressed by cells of the melanocytic lineage and are recognized by the majority of HLA-A2 restricted tumor-infiltrating lymphocytes. Heterogeneity of expression of MAA in tumor deposits may affect the natural history or response to therapy of patients with melanoma. In this study, we evaluated the expression of these MAA with a new monoclonal antibody (mAb) directed against MART-1 (M2-7C10) and the commercially available HMB45 mAb directed against gp100. Expression was tested in vitro by intracellular fluorescence analysis and in vivo by immunophenotyping of tissue specimens. Nine melanoma cell lines and 25 tissue specimens from metastatic melanoma were analyzed. One cell line did not express MART-1 or gp100. The expression of both antigens was more heterogeneous and significantly reduced (p < 0.01) in melanoma cell lines compared with melanocytes, suggesting progressive loss of expression of MAA by neoplastic cells. None of the nonmelanoma cancer lines tested stained for MART-1 or gp100. Analysis of melanoma lesions by immunohistochemistry showed significant heterogeneity of expression of both MART-1 and gp100 MAA either as a percentage of cells expressing MAA or as intensity of expression. Ten of 25 frozen sections expressed MART-1 in < 50% of the cells. In 6 of 25 lesions, immunoreactivity for MART-1 was totally absent. Fine needle aspiration of metastatic lesions seemed to yield information accurately about amount and heterogeneity of expression of MAA in tumor lesions in vivo. Heterogeneity of expression of MAA may be one of several mechanisms leading to tumor escape from immune recognition, and pretreatment evaluation of tumor lesion for expression of these antigens may help in selecting patients best suited to antigen-specific vaccine therapies.

The EMT/ITK/TSK (EMT) tyrosine kinase is activated during TCR signaling: LCK is required for optimal activation of EMT

Functional T lymphocyte activation requires concurrent stimulation of the TCR complex and an accessory molecule, most frequently CD28. We have previously demonstrated that the TEC family tyrosine kinase EMT/ITK/TSK (EMT) is activated following cross-linking of CD28. We demonstrate herein that cross-linking of the CD3 component of the TCR complex also leads to EMT activation as indicated by a rapid and transient increase in EMT tyrosine phosphorylation and kinase activity in anti-EMT immunoprecipitates. However, although concurrent cross-linking of the TCR and CD28 results in a marked increase in production of the T cell growth factor IL-2, it does not result in a significant alteration in the magnitude or duration of EMT activation. Somatic cell mutants of the Jurkat T cell line, which lack the SRC family kinase LCK (JCaM1.6), fail to produce IL-2 when stimulated through the TCR complex. EMT activation, as evidenced by increased EMT tyrosine phosphorylation and EMT-associated kinase activity, was also greatly reduced following stimulation of the TCR in the JCaM1.6 Jurkat T cell mutants that lack LCK. In support of a role for LCK in EMT activation, reconstitution of the LCK-negative Jurkat T cell line by enforced expression of LCK restored TCR-mediated EMT activation. Taken together, the data indicate that the EMT tyrosine kinase is activated following cross-linking of the TCR, a process in which LCK likely plays an important role.

The EMT/ITK/TSK (EMT) tyrosine kinase is activated during TCR signaling: LCK is required for optimal activation of EMT

Functional T lymphocyte activation requires concurrent stimulation of the TCR complex and an accessory molecule, most frequently CD28. We have previously demonstrated that the TEC family tyrosine kinase EMT/ITK/TSK (EMT) is activated following cross-linking of CD28. We demonstrate herein that cross-linking of the CD3 component of the TCR complex also leads to EMT activation as indicated by a rapid and transient increase in EMT tyrosine phosphorylation and kinase activity in anti-EMT immunoprecipitates. However, although concurrent cross-linking of the TCR and CD28 results in a marked increase in production of the T cell growth factor IL-2, it does not result in a significant alteration in the magnitude or duration of EMT activation. Somatic cell mutants of the Jurkat T cell line, which lack the SRC family kinase LCK (JCaM1.6), fail to produce IL-2 when stimulated through the TCR complex. EMT activation, as evidenced by increased EMT tyrosine phosphorylation and EMT-associated kinase activity, was also greatly reduced following stimulation of the TCR in the JCaM1.6 Jurkat T cell mutants that lack LCK. In support of a role for LCK in EMT activation, reconstitution of the LCK-negative Jurkat T cell line by enforced expression of LCK restored TCR-mediated EMT activation. Taken together, the data indicate that the EMT tyrosine kinase is activated following cross-linking of the TCR, a process in which LCK likely plays an important role.

Vascular endothelial growth factor is induced by long-term high glucose concentration and up-regulated by acute glucose deprivation in cultured bovine retinal pigmented epithelial cells

Vascular endothelial growth factor (VEGF) is closely correlated to diabetic retinopathy. Its basal production in three types of cultured retinal cells (endothelial cells, pericytes and retinal pigment epithelial cells; RPE) was examined. RPE production of VEGF was markedly higher than the rest of the cells. VEGF production in RPE was significantly elevated by 10-day, but not by 1- or 3-day exposure to 16.5 mM glucose compared to a 5.5 mM glucose group. Transient deterioration of diabetic retinopathy is frequently observed during rapid correction of glycemic control. To determine whether VEGF is up-regulated following a sharp drop in the glucose concentration or not, we examined the changes in VEGF production in RPE before and after a sudden drop in the glucose concentration. VEGF production was significantly increased by a glucose concentration decrease from 5.5 to 0.5 mM, but not by a decrease from 33 or 16.5 to 5.5 mM. These findings suggest that up-regulation of VEGF may contribute to the development of diabetic retinopathy and its worsening by hypoglycemia.

[A pediatric case of cerebral infarction following minor head injury presenting interesting neuroradiological findings]

We reported a case of juvenile cerebral infarction following minor head injury. The patient, a 12-year-old girl, developed right hemiparesis and aphasia almost immediately after having fallen from about 1 meter height during the exercise class at school. CT and MRI study showed lacunar lesions bilaterally and almost symmetrically in the paraventricular deep white matter on both sides. A new stroke area, responsible for the symptoms, was recognized about 24 hours later on CT scan just next to the lacuna of the left side. Although angiography revealed a rare anomaly of the right side aortic arch, associated with subclavian steal phenomenon, presumably of congenital in nature, no abnormality was found in the intracranial vessels. She made a rapid recovery during her hospital stay and showed no more than a slight motor weakness in her right upper extremity on discharge. The literature was reviewed on the embryology of the aortic arch and brachiocephalic arteries. We speculate that the lacunar lesions found bilaterally are dilated large normal Virchow-Robin space, and the pathogenesis of the stroke in this patient was discussed.

Lymphoproliferative disorder of granular lymphocytes (natural killer cell type) with interstitial pneumonia in a patient with familial pancytopenia

A 50-year-old woman is presented here with natural killer (NK) cell type lymphoproliferative disorder of granular lymphocytes. She was admitted to the hospital because of dyspnea on exertion. Chest X-ray revealed bilateral reticular shadows. Open lung biopsy demonstrated usual interstitial pneumonia (UIP). Her white blood cell count was 3,900/mm3, of which 55% was large granular lymphocytes (LGLs). The LGLs were CD3- CD16+CD56+, and the clonality of them was not confirmed. Despite steroid therapy, she died from exacerbation of UIP complicated with opportunistic infection. The patient, her father and son had pancytopenia. Congenital immunological abnormality might cause both large granular lymphocytosis and UIP.

Interleukin-1 beta decreases sensitivity of guinea-pig airway to potassium chloride and isoproterenol by an epithelium-dependent mechanism

Airway inflammation may cause alteration of airway responses in chronic airway diseases, such as bronchial asthma. The objective of this study was to examine whether interleukin-1beta (IL-1beta) [corrected], one of the pro-inflammatory cytokines, has a direct effect on airway functions. The effects of IL-1beta on carbachol, KCl and isoproterenol (ISO) responses of isolated guinea-pig tracheal strips were examined by measuring isometric tension in tissue bath. Responses of tracheal strips with or without epithelium to each agonist were compared before and after incubation with IL-1beta (25 ng or 250 ng/mL). Both 1 h and 5 h incubation of the strips with 250 ng/mL IL-1beta significantly decreased the sensitivity not only to KCl (P < 0.05; P < 0.01, respectively), but also to ISO (both P < 0.05) without affecting maximum contraction or relaxation. Response to carbachol was not affected by IL-1beta. Epithelial denudation abolished the effects of IL-1beta on KCl and ISO responses. Indomethacin (2 micromol/L) [corrected] reversed the effects of IL-1beta both on KCl and on ISO. These results suggest that IL-1 beta decreases the sensitivity of airway strips to KCl and ISO, possibly by stimulating prostaglandin production from the airway epithelium [corrected].

Utilization of an alternative open reading frame of a normal gene in generating a novel human cancer antigen

Tumor infiltrating lymphocytes (TILs) derived from tumor-bearing patients recognize tumor-associated antigens presented by major histocompatibility complex (MHC) class I molecules. The infusion of TIL586 along with interleukin (IL) 2 into an autologous patient with metastatic melanoma resulted in the objective regression of tumor. A gene encoding a tumor antigen recognized by TIL586 was recently isolated and shown to encode gp75. Here we report that an antigenic peptide, MSLQRQFLR, recognized by TIL586 was not derived from the normal gp75 protein. Instead, this nonamer peptide resulted from translation of an alternative open reading frame of the same gene. Thus, the gp75 gene encodes two completely different polypeptides, gp75 as an antigen recognized by immunoglobulin G antibodies in sera from a patient with cancer, and a 24-amino acid product as a tumor rejection antigen recognized by T cells. This represents the first demonstration that a human tumor rejection antigen can be generated from a normal cellular gene using an open reading frame other than that used to encode the normal protein. These findings revealed a novel mechanism for generating tumor antigens, which may be useful as vaccines to induce tumor-specific cell-mediated immunity against cancer.

Mechanism of inhibition of H+, K(+)-ATPase by sodium 2-[[4-(3- methoxypropoxy)-3-methylpyridin-2-yl]methylsulfinyl]-1H-benzimidazole (E3810)

Sodium 2-[[4-(3-methoxypropoxy)-3-methylpyridin-2-yl]methylsulfinyl ]- 1H-benzimidazole (E3810) and omeprazole inhibit gastric acid secretion through inhibition of the activity of H+, K(+)-ATPase present in parietal cell membrane vesicles, by chemical modification of SH groups in the enzyme molecule. In order to clarify the mechanism of the chemical modification, reaction products of E3810 and omeprazole with 2-mercaptoethanol under acidic conditions (pH 3, 4, 5, 6) were isolated by HPLC, and subjected to structural analysis by UV, 1H-NMR and mass spectrometry. E3810 and omeprazole appeared to undergo two kinds of reactions, affording disulfide-type products (type I reaction) and sulfide-type products (type II reaction). The rates of these reactions were determined by HPLC, and the stability of the products in the presence and absence of glutathione was investigated. In the case of E3810, type I reaction was found to proceed faster than type II reaction at every pH value studied. The type I reaction of E3810 was faster than that of omeprazole. The rate of type I reaction decreased at pH 5 and 6, especially for omeprazole, and the contribution of type II reaction increased as the pH of the reaction mixture was increased. The sulfide-type modification products were stable, whereas the formation of the disulfide-type modification products was reversed by the action of endogenous SH compounds such as glutathione. These results suggest that higher inhibitory activity of E3810 against gastric acid secretion and faster recovery of the enzyme activity after inhibition by E3810 can be expected, as compared with those of omeprazole.

[Comparative study on the efficacy of ritipenem acoxil and cefotiam hexetil in chronic lower respiratory tract infections by the double-blind method]

To objectively evaluate the efficacy, safety and usefulness of the newly developed penem oral antibiotic, ritipenem acoxil (RIPM-AC), against chronic lower respiratory tract infections, we conducted a multi-center double-blind comparative study using cefotiam hexetil (CTM-HE) as a control drug. RIPM-AC was orally administered at 200 mg, and CTM-HE at 400 mg, t.i.d. for 14 days, in principle. The results were as follows: The total number of patients enrolled in this trial was 202, of which 151 cases (RIPM-AC group: 75, CTM-HE group: 76) were evaluable for clinical efficacy. 1. The clinical efficacy rates (excellent+good) were 85.3% (64/75) in the RIPM-AC group and 80.3% (61/76) in the CTM-HE group. There was no significant difference between the two groups, hence the clinical equivalency of RIPM-AC to CTM-HE was demonstrated. 2. In the patients enrolled in the evaluation of clinical efficacy, the eradication rates of the causative organisms were 50.0% (13/26) in the RIPM-AC group and 75.0% (18/24) in the CTM-HE group, with no significant difference between the two groups. 3. Side effects were noted in 10 cases (11.0%) of the RIPM-AC group and 10 cases (10.9%) of the CTM-HE group. Abnormal laboratory test findings were observed in 8 cases(9.5%) of the RIPM-AC group and in 14 cases (16.7%) of the CTM-HE group. There were no significant differences between the two groups in the incidence of side effects and abnormal laboratory test findings. In the safety evaluation, RIPM-AC was judged to be safe in 73 cases (80.2%) and CTM-HE in 71 cases (77.2%), with no significant difference. 4. The usefulness rates (markedly useful+useful) were 79.5% (62/78) in the RIPM-AC group and 76.9% (60/78) in the CTM-HE group. There was no significant difference between the two groups. Since RIPM-AC showed clinical efficacy similar to those of CTM-HE and posed no particular safety problems, it is expected to be a useful antibiotic for the treatment of chronic lower respiratory tract infections.

[Three siblings with interstitial pneumonia]

Patient 1: A 64-year-old woman was admitted for further examination after reticulonodular shadows were found on a chest X-ray film. Idiopathic interstitial pneumonia (IIP) was diagnosed. Patient 2: The 60-year-old sister of patient 1 was admitted for further examination after reticulonodular shadows were found on a chest X-ray film. IIP was diagnosed. About half a year later, her proximal interphalangeal joints had become swollen and the result of a rheumatoid hemagglutination test was positive. Therefore, the pneumonia was suspected to have been caused by a collagen-vascular disease (CVD), rheumatoid arthritis. Patient 3: The 64-year-old brother of patient 1 was examined. A chest X-ray film revealed reticulonodular shadows that were strongly suggestive of IIP. The remaining three siblings were examined. In a 62-year-old sister, the chest X-ray film was normal, but the level of anti-nuclear antigen was elevated. The fact that the level of this antigen was high in these four siblings and that the 60-year-old sister later suffered from rheumatoid arthritis suggested the presence of a factor predisposing to CVD in these siblings. The interstitial pneumonia in these siblings may have been related to CVD.

A mutated beta-catenin gene encodes a melanoma-specific antigen recognized by tumor infiltrating lymphocytes

A number of antigens recognized by tumor-reactive T cells have recently been identified. The antigens identified in mouse model systems appear, with one exception, to represent the products of mutated genes. In contrast, most of the antigens recognized by human tumor-reactive T cells reported to date appear to represent the products of non-mutated genes. Here we report the isolation of a cDNA clone encoding beta-catenin, which was shown to be recognized by the tumor-infiltrating lymphocyte (TIL) 1290, a HLA-A24 restricted melanoma-specific CTL line from patient 888. The cDNA clone, which was isolated from the autologous melanoma cDNA library, differed by a single base pair from the published beta-catenin sequence, resulting in a change from a serine to a phenylalanine residue at position 37. Normal tissues from this patient did not express the altered sequence, nor did 12 allogeneic melanomas, indicating that this represented a unique mutation in this patient's melanoma. A peptide corresponding to the sequence between amino acids 29 and 37 of the mutant gene product was identified as the T cell epitope recognized by TIL 1290. The observation that HLA-A24 binding peptides contain an aromatic or hydrophobic residue at position 9 suggested that the change at position 37 may have generated a peptide (SYLDSGIHF) which was capable of binding to HLA-A24, and a competitive binding assay confirmed this hypothesis. The beta-catenin protein has been shown previously to be involved in cell adhesion mediated through the cadherin family of cell surface adhesion molecules. The high frequency of mutations found in members of cellular adhesion complexes in a variety of cancers suggests that these molecules may play a role in development of the malignant phenotype.

Effects of M1-selective antimuscarinics on respiratory chemosensitivity in humans

We examined effects of selective M1 antagonists on hypercapnic and hypoxic ventilatory responses in 17 healthy human volunteers. Subjects were intravenously treated with placebo, pirenzepine (10 mg) and biperiden lactate (4 mg) on three separate days in a randomized double-blind design. Ventilatory responses to hyperoxic progressive hypercapnia and isocapnic progressive hypoxia were studied after the drug administration. There were no statistically significant differences in the mean delta VE/delta PET CO2 or delta VE/delta SaO2 among the three treatments. However, the delta VE/delta PET CO2 with placebo negatively correlated with the difference in delta VE/delta PET CO2 between the biperiden and placebo studies (r=-0.65, P < 0.01), but not with that between the pirenzepine and placebo studies. On the other hand, the delta VE/delta SaO2 with placebo negatively correlated with the difference in delta VE/delta SaO2 between the pirenzepine and placebo studies (r = -0.79, P < 0.001), but not with that between the biperiden and placebo studies. These data suggest the possible involvement of M1 cholinergic receptors in the central CO2 and peripheral O2 sensing mechanisms in humans, although the degree of its involvement is not consistent among subjects. These findings may explain the interindividual variation in the control of breathing in humans.

[Trends in asthma-related death among adults in Japan, 1986-1991--analysis of responses to questionnaires sent to hospitals with at least 200 beds]

The death rate among patients with asthma in Japan has been reported by Japan's Ministry of Health and Welfare to approximately 5/100,000 population. Over the past 15 years, this rate has remained relatively constant, but it is higher than that in western countries. To clarify recent trends in adult asthma mortality, the Japan Asthma Death Investigation Committee studied the clinical characteristics of 649 patients who died of asthma between 1986 and 1991. The annual number of deaths decreased slightly: from 145 in 1986 to 89 in 1991. There was a large difference between sexes: the male:female ratio was 3:2. Most patients ranged in age from 50 to 70 years old. It is noteworthy that in one third of the patients death was caused by asphyxic-type asthma, while status asthmaticus was the cause in only 23.7%. The number of patients with mild or moderate asthma was slightly increased, although patients with severe asthma accounted for at least 70% of all deaths. The main causes of fatal asthma attacks were airway infections, fatigue, and stress. Other responses on the questionnaires indicated the following areas of concern: deficiencies in patient education, delays in treatment with corticosteroids and other antiasthma drugs, and delays in provision of emergency treatment.

[Genetic analysis of bronchial asthma in Japanese population--Fc epsilon RI beta gene and beta 2 adrenergic receptor gene]

Atopy and bronchial hyperresponsiveness are important elements for the development of bronchial asthma. On the basis of the progression of molecular biology, the genetic regulations of asthma are being examined extensively and, recently, the gene encoding a beta subunit of the high affinity receptor for IgE (Fc epsilon RI beta) and the gene encoding beta 2 adrenergic receptor (beta 2ADR) are considered to be responsible for asthma. The mutation in the Fc epsilon RI beta gene on chromosome 11q13 is reported to be associated with atopy in British families with maternal inheritance of atopy. However there is no such an association between atopy and 11q13 in Japanese families. The polymorphisms in the beta 2 adrenergic receptor gene are reported to be related to the degree of agonist promoted downregulation of the receptor, and these polymorphisms are found to affect the severity of asthma. There is also evidence which supports a relationship between the polymorphism of the receptor and airway hyperresponsiveness in Japanese families.

[Research trends in molecular genetics of respiratory medicine]

In order to identify necessary or susceptibility genes of respiratory diseases, molecular genetic approaches have been chosen more frequently than before because a tremendous number of anonymous markers over the human genome are now available. However, conventional linkage analysis such as the maximum likelihood method and affected sib-pair analysis have limitations mainly due to heterogeneity of disease genes. Association studies have more power to detect susceptibility genes, however, they tend to yield more false positive results than linkage studies unless corrected for multiple observations. There are some new methods potentially applicable to a genome-wide search for candidate genes. Each method has advantages and disadvantages. Reverse genetics is promising but destined to return to regular biochemical, physiological, and clinical approaches of respiratory medicine.

Effect of 4G-beta-D-galactosylsucrose (lactosucrose) on fecal microflora in patients with chronic inflammatory bowel disease

Metabolic interaction between the intestinal microflora and the host has been suggested to play a role in the pathogenesis of chronic inflammatory bowel disease. Elemental or low-fat, low-residual diets in patients with Crohn's disease or ulcerative colitis are reported to decrease anaerobic bacteria and to change the composition of the intestinal microflora. We examined the effect of an indigestible agent, 4G-beta-D-galactosylsucrose (lactosucrose), which is selectively utilized by intestinal Bifidobacterium, on the composition of the intestinal microflora. After the administration of lactosucrose to two patients with Crohn's disease and five patients with ulcerative colitis for 2 weeks, significant induction of the growth of Bifidobacterium was observed, and significant reduction in the population level of Bacteroidaceae was seen. Bowel movements improved in four patients. The intestinal environment, estimated by measuring fecal pH, fecal levels of short-chain fatty acids and putrid products, and the urinary secretion of indican, also improved in these patients. These results suggest that lactosucrose may be useful for patients with chronic inflammatory bowel disease.

Cerebral metastasis of parathyroid carcinoma

A 54-year-old female presented with a cerebral metastasis of functioning parathyroid carcinoma in the right occipital lobe. After surgical removal of the metastatic tumor, her symptoms of left hemianopsia and hypercalcemia improved. Surgical treatment should be considered in a case of brain metastasis of parathyroid carcinoma associated with secondary hyperparathyroidism to prevent metabolic complications and reduce the mass of the tumor.

[Idiopathic interstitial pneumonia and TNF gene restriction fragment length polymorphism]

Tumor necrosis factor alpha (TNF alpha) and lymphotoxin (TNF beta) are cytokines with numerous similar immunoregulatory effects. In pulmonary fibrosis, TNF alpha/beta appears to play a critical role in the regulation of the fibroproliferative response. The human TNF alpha/beta genes are located between the HLA-B and the HLA-DR region. In man 5.5 kb and 10.5 kb of TNF alpha/beta restriction fragment length polymorphic (RFLP) bands have recently been identified by means of enzyme NcoI. TNF alpha/beta production is reported to be correlated to the NcoI RFLP. In some collagen diseases, a decreasing frequency of the 10.5 kb band is reported. The two allele NcoI RFLP of the TNF alpha region, yielding bands of 5.5 kb and 10.5 kb, was investigated in normal Japanese subjects and patients with IIP. The frequency of these bands was not different between normal subjects and patients with IIP. However, in female patients, the frequency of the 5.5 kb band was significantly increased compared with those in the male patients and normal subjects. The increase of this band may have some relation to the pathogenesis of idiopathic interstitial pneumonia.