Amino acid replacements and wavelength absorption of visual pigments in vertebrates

An important unanswered question in phototransduction is how visual pigments (VPs) regulate their wavelength of maximal absorption (lambda max). By constructing the evolutionary tree for 28 opsins with known lambda max values, we can identify the times and directions of lambda max shift of different VPs. A total of 55 amino acid changes are shown to correlate with the directions of lambda max shift and might have been important in determining lambda max of a VP. Among these, three amino acid changes are already proven to be responsible in modifying the green-sensitive VP to the red-sensitive VP. The present evolutionary analysis opens a new direction in understanding the mechanism for the regulation of wavelength absorption by a VP and, more generally, in studying molecular mechanism involved in adaptive evolution.

Synthesis of oligonucleotide having a bent structure by incorporation of an interresidually cyclized uridylyl (3'-5')uridine unit

The chemical synthesis and conformational properties of interresidually cyclized uridylyl(3'-5')uridine derivatives were studied in order to introduce a stable turn structure into oligonucleotides. These cyclized molecules were analogs of uridylyl(3'-5')5-[methylamino(methyl)]-uridine which is the component of the U turn structure of tRNAarg E. coli. The conformational properties of these cyclic dinucleoside monophosphates were studied using NMR and CD spectroscopy with the aid of molecular mechanics and molecular dynamics simulations. These experiments indicated that the turn conformation could be stabilized by introducing a cyclic structure as expected. On the basis of these results, the chemical synthesis of phosphoramidite units of these cyclic dinucleoside monophosphate derivatives were studied to construct oligonucleotides having a stable bent structure.

Codon recognition by tRNA molecules with a modified or unmodified uridine at the first position of the anticodon

Effects of a single nucleoside modification at the first position of the anticodon of a transfer RNA molecule on its codon reading properties were investigated by use of a cell-free protein synthesis. We prepared two artificial tRNA molecules that differ only in the nucleotide at the first position of the anticodon. One has an unmodified uridine and the other has a 5-methoxyuridine (mo5U). These molecules were charged with labeled serine and introduced into a cell-free protein synthesis directed by a designed mRNA, and the relative codon reading efficiencies were calculated. The results showed that the modification of U into mo5U elevates the reading efficiencies of the UCU and UCG codons but reduces that of the UCA codon.

Alteration in gastric nerve fibers containing gastrin-releasing peptide in relation to the gastrin-producing cell population after truncal vagotomy in a rat model

The fine structural alteration in the gastric nerve fibers containing gastrin-releasing peptide (GRP) was studied in relation to the dynamics of gastrin-producing cells (G-cells) after truncal vagotomy in a rat model. The circulating gastrin levels were markedly elevated from the 1st day after vagotomy and the number of G-cells with positive immunoreaction for G17 and G34(1-15) was significantly increased in the vagotomized group. On the 3rd day after vagotomy, the G-cells showed conspicuous ultrastructural changes characterized by hypertrophy of the Golgi complexes and increased numbers of secretory granules. The GRP-positive nerve fibers formed a fine network in the gastric wall and were densely distributed in the oxyntic mucosa close to the blood vessels and showing varicosities composed of either small clear or GRP-positive large vesicles containing an electron-dense core. In the oxyntic mucosa of the vagotomized rats, axonal swelling of the nerves occurred on the 3rd day, and a depletion of GRP immunoreactivity was evidenced by a markedly decreased number of large-cored vesicles on the 7th day, when the serum GRP levels were also found to be markedly elevated. These findings indicate that the alteration in gastric nerve fibers containing GRP after truncal vagotomy may be related to hypergastrinemia and antral G-cell hyperplasia in the rat gastric mucosa.

Primary intraocular lymphoma mimicking late postoperative endophthalmitis

We treated a 65-year old woman with diffuse uveitis and an intraocular mass. The diffuse uveitis resolved with the administration of corticosteroids, but the intraocular mass did not respond to treatment. A transscleral biopsy of the lesion was performed. Histopathological study revealed non-Hodgkin's large-cell lymphoma. Immunohistochemical analysis showed that the tumor cells were derived from B-cells. The intraocular mass diminished after radiation therapy. The transscleral biopsy proved useful in establishing the correct diagnosis.

Overexpression of choline acetyltransferase reconstitutes discrete acetylcholine release in some but not all synapse formation-defective neuroblastoma cells

Secretion of acetylcholine (ACh) in neuroblastoma cells overexpressing choline acetyltransferase (ChAT) was examined. With transient transfection of ChAT cDNA, neuroblastoma cells, which have no endogenous ChAT and either adhere to myotubes or not, failed to form functional synapses, and thus no evidence for release of ACh was detected. Stable neuroblastoma cell lines overexpressing ChAT accumulated ACh inside the cell, and slowly released ACh to the outside of the cell in a calcium-independent fashion. However, after co-culturing them with rat muscle cells, these transformed cells adhered to myotubes and ACh was secreted in a discrete fashion into the synaptic cleft efficiently in some neuroblastoma cell lines but rather inefficiently in another cell line. The results show that the latent secretion machinery of ChAT overexpressing neuroblastoma cells either is competent or possess defect(s) in ACh release.

[Problems concerned with adult T-cell leukemia. 1) Causes of death and early diagnosis of cytomegalovirus pneumonia in adult T-cell leukemia. 2) Clinicopathological features of CD30 positive adult T-cell leukemia]

1) We studied the causes of death confirmed by autopsy or necropsy in 23 adult T-cell leukemia (ATL) patients. Of them eight showed involvement of tumor (35%), eleven infectious disease (47%) (nine cytomegalovirus (CMV) pneumonia, one varicella-zostervirus pneumonia, one pseudomonas aeruginosa pneumonia), and four others (17%). In seven recent cases treated with a new chemotherapy regimen in combination with G-CSF administration, survival was longer than in previous cases and tumor involvement as a cause of death decreased (one case, 14%). However, CMV pneumonia inclined to increase (six cases, 86%). Therefore, we tried to retrospectively detect CMV DNA in the serum of ATL patients using a nested polymerase chain reaction (PCR). CMV pneumonia was reliably diagnosed in eleven ATL patients, whereas CMV DNA was detected in all patients at the time of clinical onset of pneumonia and CMV DNA was detected only in eight patients from 7-35 days before the onset of pneumonia. These findings suggest that the nested PCR assay is a useful tool to early diagnosis CMV pneumonia in ATL patients. 2) Recently, several cases of ATL with CD30 antigen have been reported, but its clinical relevance remains unknown. Accordingly, we studied CD30 antigen expression in 36 ATL patients who had monoclonal integration of HTLV-I provirus in the tumor cells and demonstrated the immunohistochemical and clinical characteristics of these patients. CD30 antigen expression was evident in seven of these 36 patients (19.4%). A comparison of ATL cases with and without CD30 antigen expression revealed significantly large numbers of abnormal lymphocytes in the peripheral blood and lower serum calcium levels in CD30 antigen positive ATL.

Increased expression of CD48 on neutrophils activated in childhood patients with aplastic anemia

Activation-associated antigens such as CD11b, CD14 and CD64 of neutrophils have been reported. Although CD48 is an activation antigen of lymphocytes and monocytes, whether it is an activation antigen of neutrophils has not previously been examined. Herein, using FACS analysis, we examined the expression of surface CD48 on neutrophils activated in vivo by G-CSF administered for the treatment of idiopathic aplastic anemia. CD48 expression was increased 24 h after the initial G-CSF infusion and peaked within 1 week. Within a few days after discontinuation of G-CSF administration, it returned to the pretreatment level. This indicates that CD48 is an activation antigen of neutrophils.

[Outcome evaluation in putaminal hemorrhage by multiple regression analysis]

The aim of this study was to determine the factors that influence the prognosis of hypertensive putaminal hemorrhage. We investigated the outcome of the activity of daily living (ADL 1: full recovery at social life, 2: self cared, 3: required partial care at home, 4: remained bedridden, 5: vegetative state, 6: dead) one year after the onset of putaminal hemorrhage in comparison with initial data obtained on the day when it occurred. The following parameters were assessed: sex, age, side of hematoma, classification of computed tomography (CT) findings, neurological grade, degree of muscle power, hematoma volume, treatment, past history of cerebrovascular disease, and laboratory data. In 67 patients with putaminal hemorrhage, the relationships among these parameters were examined using Spearman's rank correlation analysis. Additionally, in 55 patients (24 male and 31 female) with complete data from the day of onset, multiple regression analysis was performed. The data of muscle power were handled by the quantification method. The result of Spearman's rank correlation coefficient indicated that the outcome had a positive correlation with age (correlation coefficient = 0.375), CT classification (0.595), neurological grade (0.714), hematoma volume (0.689), a past history of cerebrovascular disease (0.475), the white blood cell count (0.541), and the lactate dehydrogenase level (0.347). The outcome had a negative correlation with muscle power (-0.579) and the cholinesterase (-0.340).(ABSTRACT TRUNCATED AT 250 WORDS)

Cloning of the rhodopsin-encoding gene from the rod-less lizard Anolis carolinensis

The rhodopsin (Rh) of the lizard Anolis carolinensis has only been detected in the pineal gland which controls circadian rhythms [Foster et al., J. Comp. Physiol. (1993) 33-45]. In the present study, we isolated and sequenced a genomic DNA clone for the A. carolinensis Rh gene. The deduced amino acid (aa) sequence revealed six A. carolinensis-specific replacements in conserved aa residues among vertebrate Rhs. Four out of these six replacements (S22N, N199H, E232A and T319M) reside outside the transmembrane (TM) domains. Some of these replacements might have been required for Rh to function solely in the pineal gland.

Triglyceride transfer is required for net cholesteryl ester transfer between lipoproteins in plasma by lipid transfer protein. Evidence for a hetero-exchange transfer mechanism demonstrated by using novel monoclonal antibodies

In order to investigate the role of lipid transfer protein (LTP) in plasma lipoprotein metabolism, monoclonal antibodies (mAbs) have been raised against LTP isolated from rabbit plasma. mAbs 2-8G and 3-9F inhibited both [3H]cholesteryl ester (CE) and [3H]triglyceride (TG) transfer from low density lipoprotein (LDL) to high density lipoprotein (HDL) mediated by LTP. Although 3-9F cross-reacted with human LTP, 2-8G was species-specific for rabbit LTP. mAb 14-8H inhibited only [3H]TG but not [3H]CE transfer and was cross-reactive with human LTP. mAbs 2-8G and 3-9F interfered with association of LTP with lipid microemulsions, again 2-8G with species specificity, whereas 14-8H did not affect LTP-microemulsion binding. Thus, mAbs 3-9F and 14-8H were used for further study in human plasma. By total inhibition of CE and TG transfer by 3-9F, LTP was shown to be responsible for net mass transfer of neutral lipids between lipoprotein classes in plasma, namely of CE from HDL to very low density lipoprotein (VLDL) and TG from VLDL to LDL and HDL. Selective inhibition of TG transfer by mAb 14-8H was also able to inhibit such net neutral lipid transfer. Such effect of these antibodies was demonstrated more remarkably in the presence of cholesterol esterification. Thus, TG transfer activity of LTP was shown to be required for net CE transfer, suggesting that net neutral lipid transfer in plasma between lipoproteins occurred mainly by a hetero-exchange mechanism. Inhibition of net neutral lipid transfer in plasma did not affect cholesterol esterification occurring predominantly on HDL. Consequently, mAb inhibition of TG transfer in plasma leads to CE accumulation in HDL. It is possible that hyperalphalipoproteinemia may be induced by a mutation in LTP that causes a selective defect in TG transfer activity.

The strategy to treat disseminated neuroblastoma utilizing bone marrow transplantation: what is the surgeon's role?

The current role of surgery was evaluated in seven consecutive patients with high-risk neuroblastoma (six stage 4 patients and one stage 3, abdominal origin, and all over 12 months of age at diagnosis) treated with new modalities utilizing bone marrow transplantation (BMT). In six of these seven patients, a grossly complete excision of the primary tumor was achieved, and four have survived for 133, 69, 39, and 28 months with no further evidence of disease. The remaining patient with celiac neuroblastoma only underwent a biopsy during a second-look laparotomy after chemoradiotherapy, and thereafter developed local and distant recurrences and ultimately succumbed to the tumor. The timing of surgical intervention varied, either before or after chemotherapy, and did not appear to affect the ultimate survival. Although surgical excision of the primary tumor remains a very high priority in the overall treatment scheme, the most important factor remains the eradication of the tumor by well-planned courses of intensive chemotherapy (e.g., A1 Protocol of the Study Group of Japan). Thus, after having induced complete remission, for consolidation, it is necessary to kill all remaining tumor cells by giving supralethal doses of chemotherapy including total body irradiation (TBI) assisted by BMT.

Clinicopathological features of adult T-cell leukemia with CD30 antigen expression

Recently, several cases of adult T-cell leukemia (ATL) with CD30 antigen have been reported, but its clinical significance remains unknown. Accordingly, we studied CD30 antigen expression in ATL cases and documented the clinicopathological characteristics of these cases. Immunohistochemical and clinical characteristics were studied in 46 patients with malignant lymphoma or benign lesions of lymphoid tissue, who had antibodies against human T-cell leukemia virus type I (HTLV-I). Monoclonal integration of HTLV-I provirus was demonstrated in the tumor cells in 36 (ATL) of the 46 cases. CD30 antigen expression was evident in seven of these 36 cases (19.4%), however it was not seen in any of the ten cases lacking the integration of HTLV-I provirus. A comparison of ATL cases with and without CD30 antigen expression revealed significantly larger numbers of abnormal lymphocytes in the peripheral blood and lower serum calcium levels in ATL expressing CD30 antigen.

Molecular characterization of a class IV human alcohol dehydrogenase gene (ADH7)

Class IV alcohol dehydrogenase (ADH) is a form preferentially expressed in stomach. We report here the isolation and sequence determination of a novel human ADH gene (ADH7). Phylogenetic analysis strongly suggests that ADH7 is a functional class IV ADH gene.

Multiple origins of the green-sensitive opsin genes in fish

Vertebrate opsins are divided into four major groups: RH1 (rhodopsins), RH2 (rhodopsinlike with various absorption sensitivities), SWS (short-wavelength sensitive), and LWS/MWS (long and middle-wavelength sensitive) groups. The green opsin genes (g101Af and g103Af) in a Mexican characin Astyanax fasciatus belong to the LWS/MWS group, whereas those in goldfish belong to the RH2 group (Yokoyama 1994, Mol Biol Evol 11:32-39). A newly isolated opsin gene (rh11Af) from A. fasciatus contains five exons and four introns, spanning 4.2 kilobases from start to stop codons. This gene is most closely related to the two green opsin genes of goldfish and belongs to the RH2 group. In the LWS/MWS group, gene duplication of the ancestral red and green opsin genes predates the speciation between A. fasciatus and goldfish, suggesting that goldfish also has an additional gene which is orthologous to g101Af and g103Af.

[Combination neoadjuvant therapy with continuous intra-arterial CDDP infusion and radiotherapy for locally advanced breast cancer]

Neoadjuvant therapy combined with intra-arterial continuous infusion of CDDP and external radiation was evaluated in a patient with locally advanced breast cancer. Although only MR was observed on the primary tumor, PR was found in several metastatic lymph nodes and daughter nodules. All tumor markers elevated before treatment decreased to normal ranges only by this therapy, and histological damage was also recognized remarkably with a high concentration of free Pt (8.89 micrograms/g) in cancer tissues. Since no severe side effects appeared during the present therapy, extended radical mastectomy with wide skin resection could be performed following additional intra-arterial chemotherapy using 5-FU, epi-ADM and MMC. From this experience, it was suggested that CDDP was an useful drug in the chemotherapy for breast cancer.

Sequence-specific cleavage of oligoribonucleotide capable of forming a stem and loop structure

The precursor of an RNA molecule from T4-infected Escherichia coli cells (p2Sp1 RNA) has the capacity to cleave itself at specific positions ((UpA (137-138) and CpA (170-171)) within a possible loop and stem structure. This specific cleavage requires at least a monovalent cation and nonionic detergents. To confirm that the sequence-specific cleavage occurs autolytically, we studied the selective hydrolysis of RNA using a chemically synthesized 13-mer (GUUUCGUACAAAC) having sequences corresponding to G131-C143 of p2Sp1 RNA. The cleavage occurred at two identical sites (UpA and CpA) of a hairpin loop under physiological conditions and was affected by monovalent or divalent metals, nonionic detergent, salt, pH, and temperature. The hairpin loop domain and specific sequences are necessary for the cleavage of RNA 13-mer (GUUUCGUACAAAC).

Characterization of the secondary structure of an oligonucleotide corresponding to the autocleavage site of a precursor RNA from bacteriophage T4

We studied the secondary structure of an RNA fragment (GUUUCGUACAAAC) (R1) having the sequence corresponding to the self-cleavage domain in a precursor RNA molecule from bacteriophage T4 infected Escherichia coli cells (p2Sp1 RNA). We synthesized an oligoribonucleotide (CAAACGUACAAAC) (R3) which contained the sequence (CGUACA) proposed for the p2Sp1 RNA self-cleavage site but did not form the hairpin loop structure. The self-cleavage ability of the single stranded RNA (R3) is significantly lower than that of R1. We have also designed a modified RNA fragment (R2), which contained a noncleavable RNA with 2'-O-methylcytidine or 2-O-methyluridine. R3 did not exhibit cleavage. To further investigate the structural requirements in the cleavage reaction, we synthesized mutant RNAs which contained different bases within consensus sequences and the cleavage sites were tested for self-cleavage. Guanosine and adenosine 3'-phosphates seemed not to be susceptible to transesterification at the cleavage site. The data from native gel electrophoresis, the CD spectra and the Tm suggested that the hairpin structure is necessary for the cleavage.

Protective effect of recombinant neutrophil elastase inhibitor (R-020) on sepsis-induced organ injury in rat

Severe inflammatory responses after major surgeries, trauma, and infection develop multiple organ dysfunction. In the mechanisms of the pathogenesis of these responses, activated neutrophils are thought to be important in terms of their ability to produce various kinds of proteinases, which can degrade various proteins constructing human tissues. Among their proteinases, neutrophil elastase is the strongest serine proteinase secreted from activated neutrophils. Thus, we examined in this study the inhibitory effect and therapeutic efficacy of newly produced recombinant human Kunitz-type proteinase inhibitor (R-020), which coded the second domain of human urinary trypsin inhibitor. R-020 was effective in significantly improving the survival rate after induction of the rat lethal peritonitis model (cecal ligation and puncture-induced septic shock model). We suggest that various serine proteinases are implicated in the pathogenesis of neutrophil-related multiple organ failure and that recombinant human Kunitz-type proteinase inhibitor might be effective in the treatment of these kinds of organ dysfunction.

Characterization of an 800 kb region at 3p22-p21.3 that was homozygously deleted in a lung cancer cell line

We have characterized a homozygous deletion at 3p22-p21.3 found in a lung cancer cell line ACC-LC-5. Three yeast artificial chromosomes (YACs) were isolated from a YAC library by hybridization with two cosmid probes (cCI3-1994 and cCI3-1999) representing loci that were homozygously deleted in five lung cancer cell lines. Cloning both ends of the region deleted in the cell line ACC-LC-5 revealed the deletion was an interstitial deletion within the chromosomal arm. A cosmid contig map covering the entire region corresponding to the homozygous deletion was constructed by means of Southern hybridizations. From these results and analyses by pulsed-field gel electrophoresis, this interstitial deletion on chromosome 3p22-21.3 in this cell line was estimated to be nearly 800 kb long and is smallest among five cell lines containing the homozygous deletion. The cosmid clones representing this region will contribute important new resources for isolating the putative tumor suppressor gene(s) on chromosome 3p22-21.3.

Mutations that abolish the ability of Ha-Ras to associate with Raf-1

Recent studies have revealed that Ras can associate physically with Raf. In the present study, we tested 34 mutants of Ha-Ras carrying substitution(s) in the region of residues 23-71 for their ability to associate with Raf-1. Mouse Ba/F3 cell lysates were incubated with each mutant Ras protein, in either the guanosine 5'-[gamma-thio]triphosphate (GTP gamma S)- or the guanosine 5'-[beta-thio]diphosphate (GDP beta S)-bound form, and the anti-Ras antibody Y13-238. The immunoprecipitates were analysed for the presence of Raf-1 by Western blotting with an anti-Raf-1 antibody. Six mutants of Ras, E31K, P34G, T35S, D38N, D57A and A59T, failed to bind Raf-1. Mutations N26G, V29A, S39A, Y40W, R41A, V44A, V45E, L56A and T58A partially reduced the ability to bind Raf-1. All the other mutants could associate with Raf-1 with nearly the same efficiency as that of wild-type Ras. Thus, the Raf-I-binding ability of Ras appears to be affected by mutations in the N-terminal region, and in particular, by those in and neighboring the effector region (residues 32-40) and in the region (residues 56-59) flanking the N-terminal of Switch II. The abilities to bind Raf-1 and to induce neurite outgrowth of pheochromocytoma (PC) 12 cells correlate to each other for 22 Ras mutants. However, mutation A59T, which does not reduce the neurite-inducing or transforming activities, abolishes the ability to bind Raf-1. In contrast, mutations Y32F, K42A and L53A, which impair the neurite-inducing activity of Ras, have no effect on the Ras.Raf-1 association. Partially reduced Raf-1-binding ability was observed for mutants V29A, S39A, Y40W, R41A, V44A, L56A and T58A, which exhibit full neurite-inducing activity, and also for mutant V45E, which has no activity of neurite induction.

[Pre-operative autologous blood collection in neurosurgical patients]

Homologous transfusion has been known to cause viral infections and other complications. Recently, autologous transfusion has been adopted widely as a safer and more effective procedure to prevent these complications. The authors report the experiences of 29 patients who had been operated on after preparation of autologous blood. Furthermore, the authors report a study concerning maximum surgical blood order schedule (MSBOS) of these operations. 212 patients operated on between January, 1991 and June, 1993 were used for this study of MSBOS. Although intraoperative transfusion was performed on 14 of 29 patients, the need for homologous transfusion was avoided in 12 of these 14 patients by the use of autologous blood. The frequency of homologous transfusion was reduced significantly after the introduction of pre-operative autologous blood collection in our clinic. The patients' value of hemoglobin fell after the collection of blood but these levels were not so seriously low as to impede the performance of operations. 212 cases of operated patients were divided according to the operative methods and diagnosis for calculation of MSBOS. The results were as follows; Craniotomy and removal of glioma 5u, meningioma 11u, neurinoma 7u, AVM 5u, transsphenoidal surgery 3u, Moyamoya disease 2u and V-P or S-P shunt 0u. Pre-operative autologous blood collection is easy to achieve for scheduled neurosurgical operations, and autologous transfusion is a beneficial procedure which should be used more widely.