Metabolic studies using recombinant escherichia coli cells producing rat mitochondrial CYP24 CYP24 can convert 1alpha,25-dihydroxyvitamin D3 to calcitroic acid

Previously we expressed rat 25-hydroxyvitamin D3 24-hydroxylase (CYP24) cDNA in Escherichia coli JM109 and showed that CYP24 catalyses three-step monooxygenation towards 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3 [Akiyoshi-Shibata, M., Sakaki, T., Ohyama, Y., Noshiro, M., Okuda, K. & Yabusaki, Y. (1994) Eur. J. Biochem. 224, 335-343]. In this study, we demonstrate further oxidation by CYP24 including four- and six-step monooxygenation towards 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3, respectively. When the substrate 25-hydroxyvitamin D3 was added to a culture of recombinant E. coli, four metabolites, 24, 25-dihydroxyvitamin D3, 24-oxo-25-hydroxyvitamin D3, 24-oxo-23, 25-dihydroxyvitamin D3 and 24,25,26,27-tetranor-23-hydroxyvitamin D3 were observed. These results indicate that CYP24 catalyses at least four-step monooxygenation toward 25-hydroxyvitamin D3. Furthermore, in-vivo and in-vitro metabolic studies on 1alpha,25-dihydroxyvitamin D3 clearly indicated that CYP24 catalyses six-step monooxygenation to convert 1alpha,25-dihydroxyvitamin D3 into calcitroic acid which is known as a final metabolite of 1alpha,25-dihydroxyvitamin D3 for excretion in bile. These results strongly suggest that CYP24 is largely responsible for the metabolism of both 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3.

Two novel cysteine substitutions (C1263R and C1995S) of thyroglobulin cause a defect in intracellular transport of thyroglobulin in patients with congenital goiter and the variant type of adenomatous goiter

We analyzed the thyroglobulin (Tg) gene of 2 unrelated patients with congenital goiter and the Tg gene of 2 siblings with the variant type of adenomatous goiter. The clinical characteristics of the patients with congenital goiter and the variant type of adenomatous goiter were very similar, except for serum Tg levels, which were less than 15 pmol/L in the patients with congenital goiter, but 117-181 pmol/L in the patients with the variant type of adenomatous goiter (normal, 15-50 pmol/L). The tissue content of Tg in the thyroid glands of all 4 patients was reduced at 0.9-3.8% of total protein (normal, 19-40%). The missense mutation C1263R was detected in the 2 unrelated patients with congenital goiter; the pedigree study showed an autosomal recessive pattern of inheritance. In the 2 siblings with the variant type of adenomatous goiter, the missense mutation C1995S was homozygously detected. In the Tg complementary DNA of 110 normal subjects, the allelic frequencies of the C1263R and C1995S mutations were each less than 0.5%. Also in the normal subjects were detected 35 nucleotide polymorphisms, the insertion of 3 nucleotides, and 1 alternative splicing, each of which was not associated with any specific thyroid disease. From these data, the molecular mechanism of the C1263R and C1995S mutations was elucidated. We first analyzed the carbohydrate residues of C1263R Tg and C1995S Tg. Sensitivity to treatment by endoglycosidase H suggests that C1263R Tg and C1995S Tg were retained in the endoplasmic reticulum (ER). Also, the presence of endoglycosidase H-resistant Tg as well as endoglycosidase H-sensitive Tg in the patients with the variant type of adenomatous goiter suggests that a fraction of C1995S Tg was transported to the Golgi and associated with the mildly increased serum Tg levels. Native PAGE and Western blot analysis with anti-Tg antibody showed that C1263R Tg and C1995S Tg form high mol wt aggregates in the ER. Our results suggest that missense mutations that replace cysteine with either arginine or serine cause an abnormal three-dimensional structure of Tg. Such misfolded Tg polypeptides are retained in the ER as high mol wt aggregates.

Cobaltous chloride-induced mutagenesis in the supF tRNA gene of Escherichia coli

The spectrum of mutations induced by cobalt(II) chloride (CoCl2) was examined using plasmid pUB3 DNA, which was propagated after transfection into Escherichia coli SY1032/pKY241 host cells. The vector plasmid carried an E.coli supF suppressor tRNA gene as a target for mutations. After CoCl2 treatment, 64 independent nalidixic acid-resistant, ampicillin-resistant and Lac+ (SupF-) clones were obtained and the altered sequences of the mutated supF genes were determined. Deletions and frameshifts were the predominant mutational event (61%) induced by CoCl2 and base substitutions were induced to a lesser degree (29%). Analysis of sequence alterations at all the sites of mutation revealed that: (i) 18 of 19 base substitutions and eight of 10 frameshifts occurred at G:C sites, suggesting that the formation of N7G-Co(II) adducts may be responsible for premutagenic lesions of these mutations; (ii) short sequence repeats were mostly found at the sites of deletions and frameshifts. Slippage-misalignment is also suggested to be a mechanism for the induction of mutations at these sites.

High-dose growth hormone (GH) treatment in prepubertal GH-deficient children

Two clinical studies were conducted to determine the effect of different doses of growth hormone (GH) on prepubertal growth in GH-deficient boys. In one study, GH doses of 1.0 and 1.5 IU/kg/week (0.33 and 0.5 mg/kg/week) were given to groups of five children and compared with a conventional Japanese dose of 0.5 IU/kg/week (0.17 mg/kg/week) in 15 children. A significant dose-dependent increase in height velocity occurred in the first year of treatment, but differences between doses were not significant thereafter. In a second study, GH was administered to ten boys at a dose of 0.5 IU/kg/week for the first year, 0.75 IU/kg/week for the second year, 1.0 IU/kg/week for the third year and 0.5 IU/kg/week for the fourth and subsequent years (0.17, 0.25, 0.33 and 0.17 mg/kg/week, respectively). During the second and third years of GH treatment, these boys had significantly higher growth rates than controls, who were given GH at 0.5 IU/kg/week (0.17 mg/kg/week) throughout, indicating successful reduction in 'waning' of the treatment effect. At the end of the fourth year, the different protocols from the two studies had both resulted in a greater height SDS than the controls, and did not advance bone maturation. In conclusion, these protocols may be effective in increasing prepubertal height gain in children with GH deficiency.

[The influence of dorsal neck proprioceptive inputs on vestibular compensation--by three-dimensional analysis of neck-induced nystagmus]

The influence of dorsal neck proprioceptive inputs on vestibular compensation was investigated in 21 patients with unilateral vestibular dysfunction. Subjects neither had history of spontaneous nystagmus nor of disequilibrium, indicating that they were in a good compensated stage. However, marked nystagmus was induced by applying vibratory stimulation to the dorsal neck of the patients, using a vibrator with a frequency of 110 Hz. The nystagmus was three-dimensional as analyzed by applying computerized eye movement analysis system. Twelve of 21 patients (57%) demonstrated three components of eye movement. All subjects showed a horizontal component directed towards the contralateral side of the vestibular lesion. Vertical and torsional components of the nystagmus were exhibited by 18 and 14 subjects, respectively. The average percentages of slow phase velocity of the horizontal, vertical and torsional components were 57%, 23% and 20%, respectively. No tendency towards any of the three components was observed. Furthermore, in order to investigate the relation between dorsal neck proprioceptive inputs and vestibular outputs, especially semicircular canal outputs, the author compared the direction of the nystagmus with the orientation of the semicircular canals. Normalized average velocity vectors of the nystagmus were calculated. In most subjects, the velocity vectors of the nystagmus were related to the horizontal semicircular canal. These results suggest that by controlling the neck proprioceptive inputs, neck vibration can cause discompensation in vestibularly well-compensated subjects with unilateral dysfunction secondary to vestibular lesion, and that neck proprioceptive inputs have a great influence on the horizontal vestibulo-ocular reflex pathways. However, in a few subjects the average vectors of the nystagmus were related to the vertical semicircular canals. This suggests that the proprioceptive inputs may also be related to the vertical vestibulo-ocular reflex pathways.

Protective roles of bacterioruberin and intracellular KCl in the resistance of Halobacterium salinarium against DNA-damaging agents

Halobacterium salinarium, a member of the extremely halophilic archaebacteria, contains a C50-carotenoid namely bacterioruberin. We have previously reported the high resistance of this organism against the lethal actions of DNA-damaging agents including ionizing radiation and ultraviolet light (UV). In this study, we have examined whether bacterioruberin and the highly concentrated salts in this bacterium play protective roles against the lethal actions of ionizing radiation, UV, hydrogen peroxide, and mitomycin-C (MMC). The colourless mutant of H. salinarium deficient in bacterioruberin was more sensitive than the red-pigmented wild-type to all tested DNA-damaging agents except MMC. Circular dichroism (CD) spectra of H. salinarium chromosomal DNA at various concentrations of KCl (0-3.5 M) were similar to that of B-DNA, indicating that no conformational changes occurred as a result of high salt concentrations. However, DNA strand-breaks induced by ionizing radiation were significantly reduced by the presence of either bacterioruberin or concentrated KCl, presumably due to scavenging of free radicals. These results suggest that bacterioruberin and intracellular KCl of H. salinarium protect this organism against the lethal effects of oxidative DNA-damaging agents.

High prevalence of T354P sodium/iodide symporter gene mutation in Japanese patients with iodide transport defect who have heterogeneous clinical pictures

A missense and loss of function mutation of the Na+/I- symporter (NIS) gene, T354P [Thr354-->Pro (ACA-->CCA)], was found in the homozygous state in two unrelated Japanese patients with iodide transport defect. In this study we have identified the homozygous T354P NIS germline mutation in seven Japanese patients, including one previously reported, from five unrelated families. No other nucleotide changes were found in the coding regions and the exon-intron boundaries of the NIS gene in these seven patients. These results suggest a common prevalence of the T354P mutation in Japanese patients. Although these seven patients have the identical NIS mutation, T354P, marked heterogeneity in clinical pictures, especially concerning goiter and hypothyroidism, were noted among them. Therefore, another factor(s), but not the nature of the NIS mutation, may account for the clinical heterogeneity among patients with the iodide transport defect. We have previously reported that the NIS messenger ribonucleic acid was markedly increased in the thyroid of a patient with the homozygous T354P mutation. In this study we demonstrated that the NIS proteins in the patients' thyroids were significantly increased (approximately 10-fold) by Western blot analysis of integral membrane proteins using an antibody against the C-terminal peptide of the human NIS. Furthermore, we showed by immunohistochemical staining that the T354P mutant NIS proteins were overexpressed in the basal and lateral plasma membranes of patients' thyrocytes.

Accumulation of human T lymphotropic virus type I-infected T cells in the salivary glands of patients with human T lymphotropic virus type I-associated Sjögren's syndrome

OBJECTIVE

To clarify the involvement of human T lymphotropic virus type I (HTLV-I) in the pathogenesis of Sjogren's syndrome (SS).

METHODS

In HTLV-I-seropositive patients with SS, HTLV-I proviral DNA in the labial salivary glands (SG) was detected by polymerase chain reaction (PCR) amplification of the extracted cellular DNA, and the localization in the SG was examined by in situ PCR hybridization.

RESULTS

The cellular DNA extracted from the SG contained full HTLV-I proviral DNA, which was present in the nucleus of the infiltrating T cells, but not in either the SG epithelial cells or the acinar cells. Furthermore, the viral loads in the SG were approximately 8 times to 9 x 10(3) times higher than those in the peripheral blood mononuclear cells.

CONCLUSION

Accumulation of HTLV-I-infected T cells in the SG suggests that HTLV-I likely causes the self-reactive T cells to proliferate, which, as a result, induces SS.

Splenic artery aneurysm: value of color Doppler and the limitation of gray-scale ultrasonography

BACKGROUND

To reevaluate the advantages and limitations of gray-scale and color Doppler sonography in the diagnosis of splenic artery (Sp-A) aneurysm.

METHODS

We reviewed the gray-scale and color Doppler sonograms of five cases with Sp-A aneurysm (four patients with portal hypertension and one patient without portal hypertension). Color Doppler sonography was performed in all five patients, and power Doppler sonography was performed in three.

RESULTS

Gray-scale sonography failed to detect the aneurysm in four of five cases because of a surrounding splenorenal (Sp-R) shunt in three patients and marked calcification of the aneurysmal wall in one patient. Pulsed Doppler sonography showed a slightly turbulent pulsatile flow along the aneurysmal wall, which immediately led to the diagnosis in four cases, including the three cases with Sp-R shunt. In one case, color Doppler sonography failed to detect the aneurysm because of a markedly calcified aneurysmal wall, although power Doppler sonography could visualize the aneurysm.

CONCLUSIONS

Gray-scale sonography is not a useful diagnostic tool for Sp-A aneurysm. Clinicians should use color Doppler sonography in the evaluation of the splenic hilus in patients with Sp-R shunt to find a small Sp-A aneurysm. The addition of power Doppler sonography is helpful in visualizing calcified Sp-A aneurysms.

Molecular cloning of rat klotho cDNA: markedly decreased expression of klotho by acute inflammatory stress

We have recently identified a novel gene, termed klotho, that is involved in the suppression of several aging phenotypes. The gene encodes a membrane protein that shares sequence similarity with the beta-glucosidases of bacteria and plants. In this study, we isolated rat klotho cDNA and examined its tissue distribution in rats. The deduced amino acid sequence of rat Klotho protein was 1014 amino acids in length and 94 and 85% homologous to those of mouse and human Klotho proteins, respectively. Northern blot analysis using the rat klotho cDNA probe identified a single transcript of 5.2 kb in size expressed predominantly in the kidney, while RT-PCR detected low levels of expression also in the brain, lung, intestine, and ovaries. During development, klotho expression in the kidney was markedly augmented after birth. Chromosomal localization of rat klotho was mapped to 12q12. Northern blot analysis showed that expression of klotho was markedly decreased by lipopolysaccharide (LPS) in vivo, suggesting that expression of klotho is affected by acute inflammatory stress. The present study leads to a better understanding of the physiologic and pathophysiologic roles of Klotho.

Sonographic and color Doppler findings of gastrointestinal myogenic tumors with a marked extraluminal growth

We present five cases with gastro (four cases) and intestinal (one case) myogenic tumors with a marked extraluminal growth. In all cases, incidental discovery of an asymptomatic mass prompted further examination. One of three cases with a pedunculated growth mimicked a gallbladder cancer. The mass of a jejunal leiomyoma case changed markedly in location under probe compression. Color Doppler sonography confirmed not only the hypervascular nature of the mass but also feeding and draining vessels.

Direct repeat 3-type element lacking the ability to bind to the vitamin D receptor enhances the function of a vitamin D-responsive element

In a previous study, we identified the element which allows the maximum response to 1,25(OH)2D3 in concert with two vitamin D-responsive elements (VDREs) in the rat 25-hydroxyvitamin D3 24-hydroxylase gene promoter, and designated it an accessory element [Ohyama, Y., Ozono, K., Uchida, M., Yoshimura, M., Shinki, T., Suda, T. and Yamamoto, O. Functional assessment of two vitamin D-responsive elements in the rat 25-hydroxyvitamin D3 24-hydroxylase gene. J. Biol. Chem., 1996, 271, 30381-30385]. The accessory element located adjacent to the proximal VDRE is not capable of binding to the vitamin D receptor (VDR), while its nucleotide sequence resembles the consensus sequence of VDREs, direct repeat 3 (DR3). To clarify the difference between the accessory element and VDREs, the function of the accessory element was compared with that of VDREs. The mutated accessory elements with a single nucleotide substitution showed the capability of binding to the VDR in vitro. However, these mutants still did not act as a VDRE when driven by the heterologous SV40 promoter. The accessory element did not enhance the function of a cAMP-responsive element. The corresponding site of the accessory element in the human 24-hydroxylase is a DR4-type element, and this element did not function as an accessory element. These results indicate that a critical nucleotide sequence is necessary for the binding to the VDR and for mediating the vitamin D effect, and suggest the different regulation between the rat and human 24-hydroxylase gene.

Downregulation of the Klotho gene in the kidney under sustained circulatory stress in rats

We recently reported the isolation of the klotho gene, which in predominantly expressed in the kidney and involved in human aging phenotypes. In our previous studies, we demonstrated that the Klotho protein or its metabolites may possibly function as humoral factor(s) and protect against endothelial dysfunction because acetylcholine-mediated NO production in arteries was impaired in heterozygous klotho deficient mice (kl/+). However, the pathophysiological significance of the Klotho protein has not been clarified yet. In the present study, we examined expression of the klotho gene in the kidney of the following rat models for human diseases: (1) spontaneously hypertensive rat, (2) deoxycorticosterone acetate-salt hypertensive rat, (3) 5/6 nephrectomized rat, (4) non-insulin-dependent diabetes mellitus rat (the Otsuka Long-Evans Tokushima Fatty rat), and (5) rat with acute myocardial infarction. The expression levels of klotho mRNA in the kidney in these models were significantly lower than controls except for MI rats. This is the first report showing the expression of the klotho gene in the kidney is regulated under sustained circulatory stress such as long-term hypertension, diabetes mellitus, and chronic renal failure.

Klotho protein protects against endothelial dysfunction

Arteriosclerosis caused by aging is recognized to be a crucial risk factor of cardiovascular disease. We recently established klotho mouse which causes age-related disorders including arteriosclerosis. However, no information on endothelial function of klotho mouse or the physiological role of klotho protein as a circulating factor is available. In this report, we demonstrate that 50% effective dose of aortic relaxation in response to acetylcholine in heterozygous klotho mice is significantly greater (4 x 10(-5) M) than in wild-type mice (8 x 10(-6) M, n = 7, p < 0.05) and that the vasodilator response of arterioles to acetylcholine is significantly attenuated in heterozygous (20% effective dose; 2 x 10(-6) M) and homozygous klotho mice (>1 x 10(-5) M) as compared with wild-type mice (1 x 10(-7) M, n = 7, p < 0.05). Nitric oxide metabolites (NO-2 and NO-3) in urine are significantly lower in heterozygous klotho mice (142 +/- 16 nmol/day) than wild-type mice (241 +/- 28 nmol/day, n = 13, p < 0.05). Parabiosis between wild-type and heterozygous klotho mice results in restoration of endothelial function in heterozygous klotho mice. We conclude that the klotho protein protects the cardiovascular system through endothelium-derived NO production by humoral pathways.

The somatostatin analog, octreotide, inhibits in vitro outgrowth of smooth muscle cells from canine coronary and carotid atherosclerotic plaque tissues

Restenosis is caused by excessive neointima formation resulting from smooth muscle cell (SMC) proliferation and migration from the arterial media into the subendothelial space, stimulated by growth factors. A long-acting somatostatin analog, octreotide, activates protein tyrosine phosphatases and can inhibit the stimulatory effects of growth factors. In this study, we evaluated the effect of octreotide on SMC outgrowth from in vitro explants of both coronary and carotid arterial tissues in a canine endothelium-injury model. After 6 days of culture, SMC grew out of 33.3% and 58.3% of the explants from the injured canine carotid and coronary arterial tissues, respectively. In contrast, SMC outgrowth was not observed from any of the explants from normal canine carotid arterial tissue. Octreotide completely inhibited SMC outgrowth from injured canine carotid arterial tissue at a concentration of 10(-6) M. This agent also inhibited SMC outgrowth from injured canine coronary arterial tissue by 57% and 71% of the control value at concentrations of 10(-8) M and 10(-6) M, respectively. We conclude that our explant cell-culture model may prove to be valuable for assessing the effect of agents designed to reduce intimal proliferation, and that the use of the somatostatin analog octreotide in clinical settings may modify the high incidence of restenosis after coronary interventions by reducing SMC proliferation.

Quantitative analysis of Aconitum alkaloids in the urine and serum of a male attempting suicide by oral intake of aconite extract

A method for the quantitation of diesterditerpene-type Aconitum alkaloids and their hydrolysis products by gas chromatography-selected ion monitoring was applied to a clinical case study. A 45-year-old male attempted suicide by oral intake of Aconitum alkaloids, which are highly intoxicant extracts of Aconitum tubers. It was estimated that he had ingested approximately 11 mg of diesterditerpene-type alkaloids but was saved by intensive gastric irrigation. Mesaconitine, aconitine, hypaconitine, and their hydrolysis products were detected in the serum on the first day only. On the other hand, some alkaloids were still detectable in the urine even six days after intoxication. Aconitum alkaloids are biotransformed, and their hydrolysis products are excreted time-dependently to the urine. The urine was a useful material to identify the toxicants in the case of aconite intoxication.

Mechanisms of the genotoxic effects associated with 5-formyluracil: effect of exogenous 5'-formyl-2'-deoxyuridine

E. coli HB101 harboring plasmid pUC19 was grown in the presence of 5-formyl-2'-deoxyuridine (fdU) to evaluate the genotoxic and cytotoxic potentials associated with this DNA lesion. Cell growth was inhibited by fdU in a concentration-dependent manner, but increased mutation was not observed in the lacZ(alpha) gene of pUC19. The lack of the mutagenic effect was attributed to poor utilization of fdU as a substrate by thymidine kinase, which converts exogenous thymidine analogs to the corresponding 5'-monophosphates in the salvage pathway.

[Three patients with insulin-treated diabetes and senile dementia of Alzheimer's type]

Senile dementia of Alzheimer's type (SDAT) is reported to be less frequent in patients with Diabetes Mellitus. However the, the number of elderly people in still increasing in Japan, an is the incidence of diabetes mellitus, especially in middle-aged and elderly people. Thus, we can expect to encounter more elderly people with diabetes and SDAT. We encountered three patients with diabetes who were treated with insulin and in whom SDAT developed. In all three, control of blood glucose levels gradually worsened, despite increases in the dose of injected insulin. It was later found that they did not inject insulin properly because of SDAT. They lived alone and their dementia was not diagnosed before their admission to the hospital. In its early phase, SDAT can be difficult to diagnose, especially in patients who live alone. SDAT should be considered when the control of blood glucose levels for no apparent reason in elderly patients with diabetes.

Pitfalls of CT diagnosis of aortic dissection: nonvisualized intimal flap in the ascending aorta or aortic arch

We describe our experience with initial CT scans that failed to demonstrate an intimal flap in the ascending aorta or aortic arch that was subsequently identified on echocardiography, angiography, or MR imaging in four patients. This problem was presumably caused by the flailing motion of a thin intimal flap and localized small dissection in the ascending aorta, or transverse intimal flap within the aortic arch. Radiologists should be aware of this pitfall in CT diagnostic imaging.

Differential time course of induction of 1alpha,25-dihydroxyvitamin D3-24-hydroxylase mRNA expression in rats by 1alpha,25-dihydroxyvitamin D3 and its analogs

In order to investigate the in vivo mechanisms of target gene activation by vitamin D3 analogs, we compared the effects of two vitamin D3 analogs, 22-oxa-1alpha,25-(OH)2D3 (OCT) and 2beta (3-hydroxypropoxy) -1alpha,25-(OH)2D3 (ED-71) with that of 1alpha,25-(OH)2D3 on 1alpha,25-(OH)2D3 -24-hydroxylase[24(OH)ase] mRNA expression in the kidney and intestine of normal rats. In these experiments, all three compounds induced 24(OH)ase mRNA, but the time course of induction for each respective treatment was clearly different. OCT caused the most rapid onset of increased 24(OH)ase mRNA expression and its subsequent return to pre-injection levels. In marked contrast, ED-71 was the slowest to increase expression which was prolonged over that observed with the other compounds tested. These differences probably relate to the pharmacokinetic properties of these analogs, which are mainly generated by the affinity of analogs for the vitamin D-binding protein(DBP).

Genomic structures and chromosomal location of p91, a novel murine regulatory receptor family

Recently, we found a novel murine cell-surface glycoprotein, designated as p91, expressed mainly in myeloid cells such as macrophages and mast cells. The molecule has six immunoglobulin-like extracellular domains, a transmembrane segment, and a cytoplasmic tail containing four immunoreceptor tyrosine-based inhibition motif (ITIM) or ITIM-like sequences, resembling the structural features of human killer-cell inhibitory receptors (KIR). Here we show that p91 comprises a polymorphic gene family, harboring one potent inhibitory-type p91 and at least two other p91 genes. Tyrosine-phosphorylated, but not nonphosphorylated, synthetic peptides matching the third ITIM and the fourth ITIM-like sequences, respectively, found in the cytoplasmic portion of p91A, the sole inhibitory-type p91, were associated with the tyrosine phosphatases, SHP-1 and SHP-2. In addition, the phosphotyrosyl peptide matching the third ITIM sequence also bound the inositol 5-phosphatase, SHIP. These results support the notion that p91A may function as an inhibitory cell-surface molecule against cell activation. The p91 genes were shown to be clustered in the proximal region of mouse chromosome 7, a syntenic position of human chromosome 19 where the genes for the KIR family are found. A human cDNA clone cross-hybridizing to a murine p91 probe was isolated from a human spleen cDNA library, and was found to code for a molecule quite similar to members of the immunoglobulin-like transcript (or ILT) family. The gene was found to be located on human chromosome 19q13.3-13.4. These results establish the existence of a novel set of potent regulatory receptors in mouse and man, similar but different from the KIR family.

Novel modification of 5-formyluracil by cysteine derivatives in aqueous solution

Reactivities of 5-formyl-2'-deoxyuridine (fdU) and its 5'-monophosphate (fdUMP) to amino acids, amines and thiol compounds in neutral aqueous solution have been studied to elucidate the postmodification of the 5-formyluracil (fU) moiety in cells. fdU and fdUMP specifically reacted with cysteine and its analogs to form thiazolidine derivatives. The reaction involved condensation of the formyl group of fU with both alpha-NH2 (or NH2 at the equivalent position) and SH groups of cysteine derivatives.

Acute mesenteric ischemia. CT and plain radiographic analysis of 26 cases

The purpose of this study was to assess the computed tomography (CT) and plain radiographic findings of acute mesenteric ischemia, in an effort to elucidate its poor prognostic signs. The study group consisted of 26 cases with pathologically or angiographically proven mesenteric ischemia. The pathologically proven longitudinal extent of the bowel ischemia was graded using six degrees, and correlated with the radiographic findings. The mortality of the patients depended primarily on the extent of infarctions and the age of the patient. Patients with bowel dilation or abnormal gas in the bowel wall or portal system were prone to have wider extents of ischemia.

Sonographic findings of anomalous position of the gallbladder

Anomalous position of the gallbladder is relatively rare and has been reported only in isolated case reports. We tried to determine its ultrasound (US) findings on the basis of 18 such patients. In the left-side gallbladder group (nine patients), the gallbladder was imaged as an oval cystic mass in front of the pancreas. In all patients, the narrow neck of the gallbladder was clearly detected by US in the usual location before the main portal vein. Four of nine patients had small gallbladder stones. The retrohepatic gallbladder group (four patients) showed marked atrophy of the right lobe of the liver. Two patients had multiple gallstones in the bile ducts of the right lobe. All patients in the suprahepatic retrohepatic gallbladder group (four patients) were cirrhotic, and the anterior segment of the right lobe was markedly atrophied. In the intercostal scan, the gallbladder mimicked a perihepatic fluid. In the floating gallbladder group (one patient), the gallbladder was imaged as a cystic mass in the anterior abdominal wall. Surgical intervention showed a severely inflamed gallbladder, with small stones adhered into the anterior abdominal wall and partially ruptured. Knowledge of the wide range of US findings of malposition of the gallbladder helps in avoiding misdiagnosis.