Biomedical subjects

N Ito

Publications and source records attributed to N Ito.

At least 145 records · Page 8Linked to original sources

PubMed1998

Medium-term bioassays as alternative carcinogenicity test.

A medium-term liver bioassay system for rapid detection of carcinogenic agents using male F344 rats has been developed, in order to bridge the gap between long-term carcinogenicity tests and short-term screening assays. The system is fundamentally based on the two-stage hypothesis of carcinogenesis: initiation with diethylnitrosamine (200 mg/kg bw, i.p.) is followed by test chemical administration during the second, in combination with 2/3 partial hepatectomy. It requires only 8 weeks for animal experimental treatment and a further few weeks for quantitative analysis of immunohistochemically-demonstrated glutathione S-transferase placental form positive hepatic foci. A total of 291 chemicals/substances have already been analyzed in this laboratory and the efficacy of the system for hepatocarcinogens has thereby been well established. This bioassay is particularly useful for dose-response and chemical mixture studies, usually requiring large-scale experiments and also for evaluation of chemopreventive agents. Another bioassay, a medium-term multiorgan bioassay system, using 5 different chemical carcinogens, diethylnitrosamine (DEN), N-methylnitrosourea (MNU), N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), 1,2-dimethylhydrazine (DMH) and 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN), has also been established for rapid detection of not only hepatocarcinogens, but also other organ-target carcinogens. Rats were initially treated with a single i.p. administration of 100 mg/kg DEN, 4 i.p. administrations of 20 mg/kg MNU, 4 s.c. doses of 40 mg/kg DMH for 2 weeks and then 0.1% DHPN for 2 weeks. Test chemicals are administered after the carcinogens exposure. Animals were sacrificed at the end of week 36, and major organs were examined histologically. Carcinogenic activities of test chemicals were compared between the test chemical treated group and carcinogen exposures group (control group). It is increasingly becoming regarded that these bioassays are useful methods and are appropriate alternative tests systems for carcinogenicity risk assessment. Therefore, 'the International Conference on Harmonization (ICH) of Technical Requirements for the Registration of Pharmaceuticals for Human Use' has proposed that these two bioassays can be used as "additional tests for carcinogenic activity in vivo."

Animals↗

PubMed1998

Strongyloidiasis associated with nephrotic syndrome.

We report a nephrotic syndrome patient with eosinophilia who developed ileus, epigastralgia and malabsorption due to strongyloidiasis which became symptomatic by steroid therapy. The patient was then treated with thiabendazole and recovered. A percutaneous renal biopsy revealed minimal change nephrotic syndrome. This renal injury may be brought on by severe infection of Strongyloides stercoralis. It is important to rule out strongyloidiasis prior to corticosteroid therapy to patients from eosinophilia endemic areas.

Abdominal Pain↗

PubMed1998

Antitussive effect of azelastine hydrochloride in patients with bronchial asthma.

To investigate the efficacy of azelastine hydrochloride (azelastine, CAS 79307-93-0, Azeptin) in suppressing cough, 22 bronchial asthma patients complaining mainly of cough were given the drug for four weeks. Peak flow rates (PEFR), pulmonary function tests, capsaicin cough threshold, and bronchial hyperresponsiveness were compared pre- and post-administration. After four-week's administration of azelastine (2 mg twice daily), cough decreased as demonstrated in a significant progressive improvement of cough points. The morning PEFR (1/min) was improved significantly at one week and two weeks post-administration. Changes were from 434 +/- 26.4 pre-administration to 461 +/- 25.8 at Week 1 (p < 0.05), 462 +/- 26.7 at Week 2 (p < 0.05), 452 +/- 22.5 at Week 3, and 462 +/- 20.8 at Week 4. The evening PEFR (1/min) showed 439 +/- 22.2 pre-administration, 454 +/- 21.4 at Week 1, 464 +/- 22.4 at Week 2, 457 +/- 19.3 at Week 3 and 467 +/- 17.8 at Week 4, improvement being significant at Week 1 (p < 0.05). Regarding pulmonary function tests no significant changes were observed. FVC (liter), FEV1 (liter), and FEV1/FVC (%) were 3.45 +/- 0.86, 2.68 +/- 0.52, and 83.6 +/- 5.93 pre-administration; and 3.48 +/- 0.21, 2.72 +/- 0.65, and 84.1 +/- 6.21 post-administration, respectively. The capsaicin cough threshold [Ccap (mumol/l)] showed significant improvement, changing from 5.95 (0.016-50.0) pre-administration to 19.7 (0.08-50.0) post-administration (p < 0.05). Conversely, an index of bronchial hyperresponsiveness, Dmin (mg/dl;U), showed no significant changes (14.9 +/- 5.2 vs. 19.7 +/- 5.3). These results suggest that azelastine inhibits cough in patients with bronchial asthma by increasing the level of the cough threshold without changing bronchial hyperresponsiveness.

Adolescent↗

PubMed1998

[A case of ruptured P4 segment aneurysm of the posteior cerebral artery: therapeutic pitfalls encountered when dealing with the multiple intracranial aneurysms].

A P4 segment aneurysm of the posterior cerebral artery has rarely been described. A case of ruptured P4 segment aneurysm, which re-ruptured after clipping procedure for unruptured internal carotid artery aneurysm, was reported. A 57-old-man had sudden onset of severe headache and vomiting and was transferred to our hospital. CT scan on admission showed diffuse subarachnoid hemorrhage dominantly extending to the tentorial surface and the occipital interhemispheric tissue. Four-vessel angiography demonstrated a right internal carotid-posterior communicating artery junction aneurysm, and its neck clipping was performed on day 5. Intraoperative inspection of the whole appearance of the aneurysm was difficult because of the aneurysm existing on the ventral portion of the internal carotid artery and definite diagnosis of the bleeding source was not obtained. On day 23, he complained of severe headache and restricted vision and CT scan showed intracerebral hematoma in the left occipital lobe with intraventricular hemorrhage. The angiograms and CT scan on admission were reexamined, and another aneurysm on the left parieto-occipital artery (P4 segment) was retrospectively identified. The ruptured P4 segment aneurysm was obliterated via the interhemispheric approach and the patient enjoyed an uneventful postoperative course. When a thick subarachnoid hemorrhage distributed in the occipital interhemispheric fissure, quadrigeminal cistern, and ambient cistern is encountered, the existence of a possible P4 segment aneurysm should be suspected. Correct initial diagnosis and definite treatment of the ruptured lesion in the acute stage is essential in dealing with SAH-patient with multiple aneurysms. When they are unruptured lesions at a common aneurysm site, the existence of an unusually located aneurysm should not be overlooked as the possible source responsible for symptoms.

Aneurysm, Ruptured↗

PubMed1998

[A case of crushing head injury with bilateral abducens and facial nerve palsies].

A 20-year-old male was admitted to our hospital suffering from a crushing head injury. At accident, his head had been compressed by the printing machine on both temporal regions. He remained at dull conscious. On admission one hour after the injury, he showed bilateral sixth-nerve and seventh nerve palsies and bleeding from the nose. CT scan showed marked pneumocephalus, traumatic subarachnoid hemorrhage, fluid collections in the bilateral sphenoid sinuses and right mastoid air cells. Bone CT disclosed bilateral temporal bone fractures. MRI did not show cerebral parenchymal damage. He recovered fully conscious at four hours after the injury, but cranial nerve palsies sustained over 30 days after the injury. Bilateral decompression of the facial canal were performed at day 31. At one year after the injury, bilateral abducens nerve palsies and facial nerve palsies recovered incompletely (grade III). The case report and the mechanism of such cranial nerve injuries by low-velocity crushing head injury is described.

Abducens Nerve↗

PubMed1997

Sulfated lipids as inhibitors of pancreatic trypsin and chymotrypsin in epithelium of the mammalian digestive tract.

Cholesterol sulfate and I3SO3-GalCer, which were commonly contained in the epithelia of mammalian digestive tracts, were found to inhibit the activities of typical digestive enzymes, pancreatic trypsin and chymotrypsin, but steroid sulfates, gangliosides and the other membrane constituents did not show any inhibitory activity. The preincubation of trypsin with I3SO3-GalCer at 37 degrees C for 10min was necessary to inhibit the activity of trypsin, but cholesterol sulfate showed its inhibitory activity without preincubation. Sulfated lipid-treated enzyme gave the same Km as and lower Vmax than those of the original enzymes. Also, both sulfated lipids inhibited pronase from Streptomyces griseus, but not lysyl endopeptidase from Achromobacter lyticus. These findings indicate that cholesterol sulfate and I3SO3-GalCer in the digestive tract function as epithelial inhibitors to prevent tissue injury by endogenous and exogenous proteases.

Animals↗

PubMed1997

Pancreatic DNA adducts formed in vitro and in vivo by the food mutagens 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeA alphaC).

Genotoxic heterocyclic amines have been detected in grilled or fried meat and tobacco smoke. Among these, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeA alphaC) have been shown to induce tumours in rodents in several organs. Here we report on the DNA adduct formation by PhIP and MeA alphaC in vitro and in vivo, both in rat hepatic and rat pancreatic tissues or cells. Using 32P-postlabelling analysis both compounds were shown to induce a dose-dependent DNA modification in primary rat hepatocytes that was correlated with cytotoxicity in these cells. In explanted rat pancreas maintained in dynamic short-term organ culture MeA alphaC was shown to induce covalent DNA adducts. No DNA adducts were observed with PhIP in this assay. DNA adducts were observed in the liver and the pancreas of F344 rats treated with PhIP, with a 36-times higher level of adducts in the pancreas, confirming data reported earlier. DNA adduct levels induced by feeding 32, 160 or 800 ppm MeA alphaC in the diet were dose-dependent and higher in the liver compared with other organs including pancreas. While for PhIP the N2-(desoxyguanin-8-yl)-derivative was accounting for more than 90% of DNA adducts detected, in the case of MeA alphaC the N2-(desoxyguanin-8-yl) adduct was predominant in vitro and determined in vivo as one of up to 5 DNA adducts. MeA alphaC had been reported to induce preneoplastic foci and tumours in the liver and tumours and atrophy in the pancreas. In the case of MeA alphaC, the DNA adduct formation and cytotoxicity observed by us in vitro and in vivo correlate with the organ specificity of the reported pathological lesions. In the case of PhIP our in vitro data in pancreas and liver and the low adduct levels in liver in vivo also reflect the reported lack of pathological effects in these organs. In contrast, in pancreas, in vivo extraordinarily high adduct levels induced by PhIP were observed confirming studies published earlier, in spite of the fact that this compound does not cause pancreatic lesions. This enigmatic observation is discussed and the relevant literature is reviewed.

Animals↗

PubMed1997

Carcinogenicity of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in the rat.

A total of 10 highly-mutagenic heterocyclic amines have been identified to be carcinogenic in rodents. Among these, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), generally the most abundant with normal cooking procedures, induces mammary and colon carcinomas in rats in a clear dose-dependent manner. In a two-generation exposure (transplacental and trans-breast milk) experiment using Sprague-Dawley rats, an increased risk of mammary adenocarcinoma development was found in the second generation. Excretion of PhIP into the milk and transfer of PhIP to fetuses and neonates with resultant hepatic PhIP-DNA adduct formation were also confirmed. On the other hand, PhIP mammary carcinogenesis was significantly inhibited by coadministration of chlorophyllin or a synthetic antioxidant, 1-O-hexyl-2,3,5-trimethylhydroquinone, in long-term experiments using female F344 rats. The available findings strongly suggest that this food-derived carcinogen might be of importance as an environmental factor in the production of human cancers and that its carcinogenicity could be largely avoided by reducing intake of such compounds or by adoption of appropriate chemopreventive measures.

Adenocarcinoma↗

PubMed1997

Effects of the nitric oxide donor sodium nitroprusside on intracellular pH and contraction in hypertrophied myocytes.

BACKGROUND: We compared the effects of the nitric oxide donor sodium nitroprusside (SNP) on intracellular pH (pHi), intracellular calcium concentration ([Ca2+]i) transients, and cell contraction in hypertrophied adult ventricular myocytes from aortic-banded rats and age-matched controls. METHODS AND RESULTS: pHi was measured in individual myocytes with SNARF-1, and [Ca2+]i transients were measured with indo 1 simultaneously with cell motion. Experiments were performed at 37 degrees C in myocytes paced at 0.5 Hz in HEPES-buffered solution (extracellular pH = 7.40). At baseline, calibrated pHi, diastolic and systolic [Ca2+]i values, and the amplitude of cell contraction were similar in hypertrophied and control myocytes. Exposure of the control myocytes to 10(-6) mol/L SNP caused a decrease in the amplitude of cell contraction (72 +/- 7% of baseline, P < .05) that was associated with a decrease in pHi (-0.10 +/- 0.03 U, P < .05) with no change in peak systolic [Ca2+]i. In contrast, in the hypertrophied myocytes exposure to SNP did not decrease the amplitude of cell contraction or cause intracellular acidification (-0.01 +/- 0.01 U, NS). The cGMP analogue 8-bromo-cGMP depressed cell shortening and pHi in the control myocytes but failed to modify cell contraction or pHi in the hypertrophied cells. To examine the effects of SNP on Na(+)-H+ exchange during recovery from intracellular acidosis, cells were exposed to a pulse and washout of NH4Cl. SNP significantly depressed the rate of recovery from intracellular acidosis in the control cells compared with the rate in hypertrophied cells. CONCLUSIONS: SNP and 8-bromo-cGMP cause a negative inotropic effect and depress the rate of recovery from intracellular acidification that is mediated by Na(+)-H+ exchange in normal adult rat myocytes. In contrast, SNP and 8-bromo-cGMP do not modify cell contraction or pHi in hypertrophied myocytes.

Animals↗

PubMed1997

Effects of n-tritriacontane-16,18-dione, curcumin, chlorphyllin, dihydroguaiaretic acid, tannic acid and phytic acid on the initiation stage in a rat multi-organ carcinogenesis model.

The modifying effects of the naturally occurring antioxidants n-tritriacontane-16,18-dione (TTAD), curcumin, dihydroguaiaretic acid (DHGA), chlorophyllin, tannic acid and phytic acid on the initiation stage in a rat multi-organ carcinogenesis model were examined in male F344 rats. Animals were initiated with two i.p. injections of 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN), followed by two i.g. administrations of N-ethyl-N-hydroxyethylnitrosamine (EHEN), and then three s.c. injections of 3,2'-methyl-4-aminobiphenyl (DMAB) during the first 3 weeks. Starting 1 day before the first carcinogen application, groups of rats received diet containing one of the antioxidants (0.2% TTAD, the others at 1% each) until 1 week after the last carcinogen exposure. Surviving animals were killed and complete autopsies were performed at the end of week 36. Histological examination revealed no inhibitory effects in terms of the multiplicities and/or incidences of neoplastic lesions in any of the organs examined, other than a significant increase in seminal vesicle atypical hyperplasia observed in rats treated with tannic acid. Thus, the antioxidants, with the exception of tannic acid, did not show any modifying effects on the initiation stage in the present multi-organ carcinogenesis model and at the present dose levels applied.

Aminobiphenyl Compounds↗

PubMed1997

misshapen encodes a protein kinase involved in cell shape control in Drosophila.

We have identified a novel protein kinase encoded by the misshapen gene, which is required for the normal shape and orientation of Drosophila photoreceptor cells. misshapen is also expressed in the embryonic mesoderm, pole plasm and other sites of cell shape change or movement. We propose that msn may act in a signal transduction pathway leading to cytoskeletal re-arrangements.

Amino Acid Sequence↗

PubMed1997

The prostate: a target for carcinogenicity of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) derived from cooked foods.

Prostate tissues obtained from rats given a food-derived carcinogen, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), at a dose of 400 ppm in the diet for 52 weeks were histopathologically evaluated and found to contain prostate carcinomas limited to the ventral lobe in 18 of 27 cases. Atypical hyperplasias were also detected in the ventral and anterior prostate as well as the seminal vesicles. 32P-Postlabeling analysis of DNA demonstrated that PhIP-DNA adducts are produced in all lobes of the prostate of rats receiving PhIP. The findings indicate that PhIP is carcinogenic to rat prostate in addition to the previously demonstrated targeting of the colon and mammary glands, providing evidence of a possible role of PhIP in human prostate carcinogenesis and highlighting the potential importance of PhIP for man.

Animals↗

PubMed1997

Endothelin and angiotensin II stimulation of Na+-H+ exchange is impaired in cardiac hypertrophy.

We compared the effects of endothelin-1 (ET-1) on intracellular pH, intracellular [Ca2+]i, and cell contraction in hypertrophied adult ventricular myocytes from ascending aortic banded rats and age-matched controls. Intracellular pH (pH(i)) was measured in individual myocytes with SNARF-1, and [Ca2+]i was measured with indo-1, simultaneous with cell motion. Experiments were performed at 36 degrees C in myocytes paced at 0.5 Hz in Hepes-buffered solution (pH(o) 7.40) containing 1.2 mM CaCl2. At baseline, calibrated pH(i), diastolic and systolic [Ca2+]i values, and the amplitude of cell contraction were similar in hypertrophied and control myocytes. Exposure of the control myocytes to 10 nM ET-1 caused an increase in the amplitude of cell contraction to 163+/-22% of baseline (P < 0.05), associated with intracellular alkalinization (pH(i) + 0.08+/-0.02 U, P < 0.05) and a slight increase in peak systolic [Ca2+]i (104+/-11% of baseline, P < 0.05). In contrast, in the hypertrophied myocytes, exposure to ET-1 did not increase the amplitude of cell contraction or cause intracellular alkalinization (-0.01+/-0.02 U, NS). Similar effects were observed in the hypertrophied and control myocytes in response to exposure to 10 nM angiotensin II. ET-1 also increased the rate of recovery from intracellular acidosis induced by the washout of NH4Cl in the control cells, but did not do so in the hypertrophied cells. In the presence of 10 microM 5-(N-ethyl-N-isopropyl)-amiloride, which inhibits Na+-H+ exchange, ET-1 did not cause a positive inotropic effect or intracellular alkalinization in control cells. The activation of protein kinase C by exposure to phorbol ester caused intracellular alkalinization and it increased the rate of recovery from intracellular acidification induced by an NH4Cl pulse in control cells but not in hypertrophied cells. ET-1, as well as angiotensin II, and phorbol ester, fail to stimulate forward Na+-H+ exchange in adult hypertrophied myocytes. These data suggest a defect in the coupling of protein kinase C signaling with Na+-H+ exchange in adult hypertrophied myocytes.

Amiloride↗

PubMed1997

The restriction of diffusion of cations at the external surface of cardiac myocytes varies between species.

In cardiac muscle sarcolemmal structures such as T-tubules, caveolae and negatively charged protein-polysaccharides may affect the rate of cation exchange on the external surface of the cells. To test this hypothesis, we examined the rate of external cation exchange in adult rabbit and rat ventricular myocytes using a rapid solution switcher to change the bulk external solution within 4 ms. To assess the rate of diffusion of monovalent cations, we increased [K+]o from 4.4 to 6.6 or 8.8 mM and measured the time required to achieve a stable membrane depolarization. In rat myocytes, the mean time to 90% depolarization (t90) was significantly longer than that in rabbit myocytes (137 and 64 ms, respectively) and the difference in t90 was not associated with the cell size. To assess the time course of exchange of external Ca2+, we rapidly exposed the myocytes to 0 Ca2+-2 mM EGTA solution at specific time points before action potentials or voltage clamp steps, and measured the rate of alteration of the normalized peak [Ca2+]i transient (Fluo-3) or Ca2+ current. Exposure to 0 Ca2+-2 mM EGTA solution caused a decline in the intracellular calcium transient. In rat myocytes, the rate of decline in the [Ca2+]i transient was much slower (t90 > 1500 ms, the time required for 90% decline) than for the rabbit (t90 = 295 ms). Also, the rate of decline in the Ca2+ current was prolonged in rat myocytes (t90 = 910 ms) compared with rabbit myocytes (t90 = 241 ms). These data indicate that there is a restricted space on the external surface of sarcolemma which limits diffusion of divalent cations more markedly than monovalent cations. The extent of this limitation of cation diffusion varies between species, and may have functional significance.

Animals↗

PubMed1997

A virus-neutralizing epitope on the glycoprotein of rabies virus that contains Trp251 is a linear epitope.

We have established a hybridoma producing monoclonal antibody (MAb) against a linear epitope of glycoprotein (G protein) of the RC-HL strain of rabies virus. This MAb15-13 showed almost the same neutralizing activity to all of five rabies fixed strains, including RC-HL, and reacted to the denatured G protein in western blot analysis. To characterize and map this linear epitope, an antigenic variant NR15-13 was selected from RC-HL strain in the presence of neutralizing MAb15-13. The variant reacted with MAb15-13 in an immunofluorescent antibody test but was not neutralized by the antibody and the antibody did not bind to the variant G protein in a Western blot analysis. The variant NR15-13 had an amino acid substitution at position 251 of the G protein, where tryptophan of the parental RC-HL strain was replaced by arginine. Site-directed mutagenesis analysis using the expression system in simian COS7 cells revealed that a single amino acid substitution at 251-tryptophan by arginine on the G protein of the parental RC-HL strain abolished the antigenicity of the epitope for MAb15-13 in western blot analysis, and the replacement of 251-arginine by tryptophan recovered the activity. These results strongly suggest that tryptophan at position 251 on the G protein is essential for construction of the linear epitope against MAb15-13.

Animals↗

PubMed1997

Characterization of 26S proteasome alpha- and beta-type and ATPase subunits from spinach and their expression during early stages of seedling development.

Three kinds of cDNAs encoding 26S proteasome subunits have been cloned from spinach (Spinacia oleracea L.). These genes, designated as SOPSC8, SOPSC1 and SOPRS7, encode an alpha-type and a beta-type subunit of the 20S catalytic core, and an ATPase subunit of the 19/22S regulatory complex, respectively. The deduced protein sequences showed high sequence similarities to other proteasome alpha- and beta-type and ATPase subunit proteins. Southern blot analysis indicates that there are additional members of these dispersed proteasome families in the spinach genome. These three subunit genes are expressed simultaneously during germination and reach a maximum one day after sowing followed by a decline. The expression of these genes also increases during cotyledon senescence.

Adenosine Triphosphatases↗

PubMed1997

Aberrant glycosylation based on the neo-expression of poly-N-acetyllactosamine structures in squamous cell carcinomas of the head and neck.

An immuno- and lectin-histochemical study was performed to investigate the aberrant expression of blood group-related antigens and poly-N-acetyllactosamine structures in squamous cell carcinomas of the maxillary sinus, the larynx, the apipharynx, the hypopharynx, the oral cavity, the parotid gland and the tonsil from 52 patients using monoclonal antibodies against A, B and H antigens, and six lectins, UEA-I, PNA, VVA-B4, PWM, LEA and DSA. In addition, GSA-II staining following endo-beta-galactosidase digestion procedure was also applied. A, B and H antigens were expressed in most normal epithelial cells of head and neck organs, and depended on the patient blood type. However, in squamous cell carcinoma, A antigen was not detected in eight out of 25 individuals of blood groups A and AB, although B antigen was consistently expressed in carcinoma cells from all the B and AB individuals. On the other hand, H antigen was expressed in carcinoma cells not only from all blood group O individuals, but from 32 out of 35 individuals of blood groups A, B and AB. T and Tn antigens, which are recognized by PNA and VVA-B4, were strongly expressed in carcinoma cells from 40 and 42 out of 52 individuals respectively. Reactivity with GSA-II staining following endo-beta-galactosidase digestion, which recognizes linear poly-N-acetyllactosamine structures, was found in a few malignant cells from 21 individuals. Staining with anti-A, -B and -H monoclonal antibodies and UEA-I lectin was diminished after endo-beta-galactosidase digestion in some cases. Lectins specific for poly-N-acetyllactosamine, such as PWM, LEA and DSA, exhibited reactivity in some malignant cells from 30, 22 and 32 out of 52 individuals respectively. These results suggested that the expression of the blood group-related antigens is suppressed and immature carbohydrate chains, that is H, T and Tn antigens, are accumulated in squamous cell carcinomas of the head and neck. The results further suggested that poly-N-acetyllactosamine structures are simultaneously synthesized along with the deletion of A antigen and the accumulation of precursors.

ABO Blood-Group System↗

PubMed1997

Increased circulating transforming growth factor beta1 in a patient with giant hepatic hemangioma: possible contribution to an impaired immune function.

A patient, having a huge hepatic hemangioma, presented with decreases in the number of peripheral lymphocytes and in serum concentrations of gamma-globulin and immunoglobulin (Ig) G, and a negative purified protein derivatives skin test, indicating that the patient's immunity was impaired. The plasma concentration of transforming growth factor beta1 (TGF-beta1), a potent immunosuppressor, in the patient was markedly elevated (113 ng/mL, normal < 5). After the surgical removal of the tumor, the plasma TGF-beta1 concentration decreased, and the patient's immunity was restored to normal. Northern blot analysis showed an overexpression of the TGF-beta1 gene in the hemangioma tissue, while normal control liver tissue expressed undetectable levels of TGF-beta1 messenger RNA. These results suggest that the elevated levels of TGF-beta1 in the plasma were derived from the giant hemangioma tissue and may have contributed to the impaired immune function in the patient.

Cytokines↗