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Lymphoproliferative disorders (LPDs) are serious complications that arise in patients with rheumatoid arthritis (RA) receiving immunosuppressive drugs (ISDs). Here, we reported a 73-year-old woman diagnosed with RA at 60 years of age and treated with methotrexate, bucillamine, prednisolone, and infliximab. She was referred to our hospital, Osaka Metropolitan University Hospital, with general malaise, pancytopenia, a right adrenal mass, and enlarged periaortic lymph nodes. Epstein-Barr virus was detected in serum. We suspected LPD development and performed a bone marrow biopsy, on which no malignant cells could be detected. Upon ISDs withdrawal, her symptoms and blood counts improved, and the right adrenal mass and enlarged lymph nodes regressed. The patient was followed up for clinical LPD. However, 7 months after the initial visit to our hospital, she developed fever and pancytopenia. A repeat bone marrow biopsy confirmed the diagnosis of Epstein-Barr virus-positive diffuse large B-cell lymphoma complicated by haemophagocytic syndrome. After pulse steroid therapy, the patient received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone therapy, which resulted in a complete response. In conclusion, when LPDs develop in patients with RA during ISD treatment, LPDs can progress and complicate haemophagocytic syndrome after partial remission following ISDs withdrawal. Therefore, we should carefully follow up RA patients with LPDs, and aim to achieve an early diagnosis of LPD and promptly initiate chemotherapy., (© Japan College of Rheumatology 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Abnormal gut motility is a feature of several mitochondrial encephalomyopathies, and mutations in genes such as TYMP and POLG, have been linked to these rare diseases. The human genome encodes three DNA ligases, of which only one, ligase III (LIG3), has a mitochondrial splice variant and is crucial for mitochondrial health. We investigated the effect of reduced LIG3 activity and resulting mitochondrial dysfunction in seven patients from three independent families, who showed the common occurrence of gut dysmotility and neurological manifestations reminiscent of mitochondrial neurogastrointestinal encephalomyopathy. DNA from these patients was subjected to whole exome sequencing. In all patients, compound heterozygous variants in a new disease gene, LIG3, were identified. All variants were predicted to have a damaging effect on the protein. The LIG3 gene encodes the only mitochondrial DNA (mtDNA) ligase and therefore plays a pivotal role in mtDNA repair and replication. In vitro assays in patient-derived cells showed a decrease in LIG3 protein levels and ligase activity. We demonstrated that the LIG3 gene defects affect mtDNA maintenance, leading to mtDNA depletion without the accumulation of multiple deletions as observed in other mitochondrial disorders. This mitochondrial dysfunction is likely to cause the phenotypes observed in these patients. The most prominent and consistent clinical signs were severe gut dysmotility and neurological abnormalities, including leukoencephalopathy, epilepsy, migraine, stroke-like episodes, and neurogenic bladder. A decrease in the number of myenteric neurons, and increased fibrosis and elastin levels were the most prominent changes in the gut. Cytochrome c oxidase (COX) deficient fibres in skeletal muscle were also observed. Disruption of lig3 in zebrafish reproduced the brain alterations and impaired gut transit in vivo. In conclusion, we identified variants in the LIG3 gene that result in a mitochondrial disease characterized by predominant gut dysmotility, encephalopathy, and neuromuscular abnormalities., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Precise regulation of cytoskeletal dynamics is important in many fundamental cellular processes such as cell shape determination. Actin and microtubule (MT) cytoskeletons mutually regulate their stability and dynamics. Nonmuscle myosin II (NMII) is a candidate protein that mediates the actin-MT crosstalk. NMII regulates the stability and dynamics of actin filaments to control cell morphology. Additionally, previous reports suggest that NMII-dependent cellular contractility regulates MT dynamics, and MTs also control cell morphology; however, the detailed mechanism whereby NMII regulates MT dynamics and the relationship among actin dynamics, MT dynamics and cell morphology remain unclear. The present study explores the roles of two well-characterized NMII isoforms, NMIIA and NMIIB, on the regulation of MT growth dynamics and cell morphology. We performed RNAi and drug experiments and demonstrated the NMII isoform-specific mechanisms-NMIIA-dependent cellular contractility upregulates the expression of some mammalian diaphanous-related formin (mDia) proteins that suppress MT dynamics; NMIIB-dependent inhibition of actin depolymerization suppresses MT growth independently of cellular contractility. The depletion of either NMIIA or NMIIB resulted in the increase in cellular morphological dynamicity, which was alleviated by the perturbation of MT dynamics. Thus, the NMII-dependent control of cell morphology significantly relies on MT dynamics., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.)

Background: Although guidelines recommend that blood pressure (BP) should be measured on a bare arm, BP is sometimes measured over clothing in clinical settings., Objective: To assess the accuracy of BP measurements over clothing rolled up to the elbow in clinical settings., Methods: This was a cross-sectional study to a total of 186 individuals recruited from a primary care clinic and two day-care facilities between July and September 2014. Main outcome measures were BP measurements on (i) a bare arm, (ii) over the sleeve of a cardigan and (iii) over the sleeve of a cardigan rolled up to the elbow. BP was compared across measurement conditions using the paired t-test and multiple analysis of variance adjusting for age, sex, measurement order and interaction between clothing condition and measurement order., Results: Of 186 subjects, 38.5% were male. Mean age was 74.6 years. Mean BP with a bare arm, over a sleeve and over a rolled-up sleeve was 128.9 (SD 19.1)/67.4 (10.8) mmHg, 132.8 (21.0)/72.6 (11.5) mmHg and 133.4 (21.3)/74.4 (12.1) mmHg, respectively. There were significant differences in BP between the bare arm and over a cardigan sleeve (P < 0.001) and the bare arm and over a rolled-up cardigan sleeve (P < 0.001). BP differences were significant even after adjusting for age group, sex, measurement order and interaction between clothing condition and measurement order., Conclusions: Although previous studies have suggested BP measurements over clothing are acceptable, our results suggest that BP should be measured on bare arms as recommended by guidelines whenever feasible., (© The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The 6- to 7-MeV high-energy gamma-ray calibration field by the (19)F(p, αγ)(16)O reaction is to be served at the Japan Atomic Energy Agency. For the determination of air kerma rates using an ionisation chamber in the 6- to 7-MeV high-energy gamma-ray field, the establishment of the charged particle equilibrium must be achieved during measurement. In addition to measurement of air kerma rates by the ionisation chamber with a thick build-up cap, measurement using the ionisation chamber and a build-up plate (BUP) was attempted, in order to directly determine air kerma rates under the condition of regular calibration for ordinary survey meters and personal dosemeters. Before measurements, Monte Carlo calculations were made to find the optimum arrangement of BUP in front of the ionisation chamber so that the charged particle equilibrium could be well established. Measured results imply that air kerma rates for the 6- to 7-MeV high-energy gamma-ray field could be directly determined under the appropriate condition using an ionisation chamber coupled with build-up materials., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The ambient dose equivalents H*(10) of photons mixed in the 144, 250 and 565 keV monoenergetic neutron fields were evaluated using measurements from an NaI(Tl) detector and calculations done using the MCNP-ANT code. It was found that H*(10) of the photons produced in the target assembly dominates the dose, particularly near the target. The H*(10) of the photons produced in other materials in the field increases with the increase in distance from the target and could not be neglected at a large distance from the target. The ratios of the H*(10) of the mixed photons to that of the monoenergetic neutrons for 144, 250 and 565 keV neutron fields, were evaluated to be below 5.5, 6.9 and 1.5 %, respectively. The ratios were calculated at calibration points between 100 and 500 cm from the target., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

A portable, light-weight long counter (LC) with small dimensions was developed. This LC consists of a (3)He thermal neutron counter, a cylindrical moderator and outer shields. It was designed to have an almost flat response in a neutron energy range of 0.4 eV to 5 MeV. The portable LC has a radius of 11 cm and a length of 39 cm. Its weight was successfully reduced to 15 kg. Polystyrene was employed instead of polyethylene for the front part of the moderator in order to increase the sensitivity to low-energy neutrons. The response function calculated using the MCNP code was consistent with the results of experiments using monoenergetic neutron calibration fields., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Xlr6 is a novel but uncharacterized X-linked gene that is upregulated in meiotic prophase I during mouse spermatogenesis. Xlr6 belongs to the Xlr gene family, which includes a component of the axial/lateral element of the synaptonemal complex, Sycp3, and its transcripts are abundant in the fetal ovary and adult testis. Immunostaining and Western blot analysis demonstrate a diffuse localization pattern for this protein in the nucleus and an association with chromatin during the leptotene and zygotene stages. In males, XLR6 accumulates at the XY body of early pachytene to midpachytene spermatocytes, although the Xlr6 gene is subjected to meiotic sex chromosome inactivation. During the late pachytene and diplotene stages, the XLR6 protein relocalizes from the XY body to the nucleolus and, eventually, disappears by diakinesis. In females, XLR6 disappears at the pachytene stage, whereas it accumulates at the unpaired chromosomes occasionally observed in wild-type female mice. Although the amino acid sequence of XLR6 has a high similarity with SYCP3, its distinct localization pattern and dynamism suggest a unique chromatin modification function that leads to the transcriptional repression of ribosomal DNA in addition to sex chromosome genes.

Aims: Ethanol constricts hepatic vessels of isolated perfused livers of rats, but not dogs. However, it is not known whether ethanol constricts or dilates the hepatic vessels in other species such as guinea pigs and mice. In addition, the sites of hepatic venoconstriction induced by ethanol were not known in rat livers. We therefore studied the effects of ethanol on the segmental hepatic vascular resistance and liver weight of mice, rats and guinea pigs., Methods: The isolated livers were portally perfused with diluted blood at constant flow. The sinusoidal pressure was measured by the double occlusion method and was used to determine the pre- and post-sinusoidal resistance. The change of liver weight was also measured. Ethanol was administered cumulatively into the perfusate to gain clinically relevant concentrations of 1-300 mM., Results: Ethanol dose dependently caused predominant pre-sinusoidal constriction in livers of all three species. When compared with the livers of the guinea pigs and rats, the mouse livers were the weakest in response. Dose-dependent decreases in liver weight and bile flow accompanied predominant pre-sinusoidal constriction in guinea pigs and rats., Conclusion: Ethanol predominantly constricts pre-sinusoids in rat, guinea pig and mouse livers, although the mouse liver response was much weaker. Ethanol-induced pre-sinusoidal constriction is accompanied by reduction of liver blood volume in guinea pigs and rats.

Histamine dehydrogenase from Nocardioides simplex (HmDH) which catalyzes the oxidative deamination of histamine is an iron-sulphur-containing flavoprotein. For our further understanding on the intramolecular electron transfer process, the reductive half reaction of HmDH with histamine has been studied by stopped flow spectrophotometry at pH 7.5 and 10. The reaction at pH 7.5 is found to be analysed on a kinetic model composed of three sequential first-order reactions. The first fast phase, of which the rate constant shows a hyperbolic dependence on the histamine concentration, is assigned to a direct two-electron reduction of the oxidized flavin (CFMN(O)) by histamine with no involvement of the semiquinone form of the flavin (CFMN(S)). The second moderate process is the substrate-independent intramolecular single-electron transfer from the reduced flavin to the oxidized iron-sulphur cluster. The third slow process is considered to reflect the second binding of histamine to CFMN(S), which is responsible for the substrate inhibition. At pH 10, the reaction is analysed with one pseudo-first-order reaction phase which is substrate-dependent two-electron reduction of CFMN(O) coupled with the subsequent fast intersubunit single-electron transfer. The UV-vis spectroscopy of HmDH suggests the deprotonation of Tyr residues, which seems to cause the switching of the electron transfer property.

Histamine dehydrogenase from Nocardioides simplex (nHmDH) is a homodimer containing one 6-S-cysteinyl FMN (CFMN) and one [4Fe-4S] cluster per monomer. nHmDH catalyses the oxidative deamination of histamine to ammonia and imidazole acetaldehyde, but histamine inhibits its catalytic activity at high concentrations. We mutated gene-encoded residues (Tyr180, Gly268 and Asp269) near CFMN to understand the biophysical meaning of the substrate inhibition. Three mutants Y180F, G268D/D269C and Y180F/G268D/D269C were expressed by considering the DNA sequence alignment of histamine dehydrogenase from Rhizobium sp. 4-9 (rHmDH), which does not suffer from the substrate inhibition. The Y180F/G268D/D269C mutation to mimic rHmDH successfully suppressed the inhibition, although the catalytic activity decreased. The substrate inhibition was weakened by the Y180F mutation, but G268D/D269C was still susceptible to the inhibition. It was found that it also causes changes in the UV-vis absorption spectra of the substrate-reduced form and the redox potential of the enzymes. The characterization suggests that the thermodynamic preference of the semiquinone form of CFMN in the two-electron-reduced subunit of the enzyme is responsible for the substrate inhibition. However, destabilization of the semiquinone form leads to kinetic hindrance due to the uphill single electron transfer from the fully reduced CFMN to the [4Fe-4S] cluster.

Objective: Elastography is a technique for detecting the stiffness of tissues. We applied elastography for the diagnosis of prostate cancer and evaluated the usefulness of elastography for prostate biopsy., Methods: The subjects of this study were 311 patients who underwent elastography during prostate needle biopsy at Hitachi General Hospital. Strain images obtained during compression of the prostate tissue were displayed on a monitor and recorded on the computer. The elastographic moving images (EMI) were evaluated retrospectively. The evaluable images and biopsy results were compared in terms of the feasibility and accuracy., Results: The median patient age was 67 years (range 50-85 years), the median serum level of prostate-specific antigen was 8.4 ng/ml (range 0.3-82.5 ng/ml) and the median prostate volume was 42.6 ml (range 12-150 ml). Among the 311 patients, prostate cancer was detected in 95 patients (30%) by biopsy. The diagnostic sensitivity was 37.9% for digital rectal examination (DRE) and 59.0% for transrectal ultrasonography (TRUS), whereas it was 72.6% for elastography and 89.5% for the combination of TRUS and elastography. Elastography-positive EMIs with negative biopsies were eventually determined to be due to benign prostatic hyperplasia., Conclusion: Elastography has a significantly higher sensitivity for the detection of prostate cancer than the conventionally used examinations including DRE and TRUS. It is a useful real-time diagnostic method because it is not invasive, and simultaneous evaluation is possible while performing TRUS.

Histamine dehydrogenase from Nocardioides simplex is a homodimer and belongs to the family of iron-sulfur flavoproteins having one [4Fe-4S] cluster and one 6-S-cysteinyl FMN per monomer. In the reductive titration with histamine, two-electron reduction occurred per monomer at pH<9, while single-electron reduction proceeded at pH>9. The substrate-reduced histamine dehydrogenase yielded an electron paramagnetic resonance spectral signal assigned to the flavin semiquinone. The signal intensity increased with pH up to pH 9 and reached a maximum at pH>9. These unique features are explained in terms of the redox potential of the cofactors, where the redox potential was evaluated over a pH range from 7 to 10 by using a spectroelectrochemical titration method for the flavin and cyclic voltammetry for the [4Fe-4S] cluster. The bell-type pH dependence of the enzymatic activity is also discussed in terms of the pH dependence of the centers' redox potential.

Background: Maintenance of a competent permeability barrier in the face of external and internal stressors requires signals between the stratum corneum interface and the metabolic machinery in the underlying nucleated layers. For example, reductions in the ion gradients for Ca2+ after acute barrier disruption stimulate lamellar body (LB) secretion, a response required to restore barrier homeostasis. Although alterations in external K+ levels also regulate barrier recovery after acute insults, the mechanisms whereby K+ regulates barrier function remain unknown., Objectives: To evaluate effects of regulators of K+ channels on barrier homeostasis in hairless mice., Methods: We tested a number of chemically different drugs that alter intracellular K+ levels. Results Single applications of either K+ channel openers (i.e. 1-EBIO, minoxidil, diazoxide) or the K+ ionophore, valinomycin, accelerated barrier recovery after acute insults to murine skin, paralleled by a reduction in intracellular K+ levels in cultured human keratinocytes. In contrast, applications of K+ channel blockers (i.e. gilbenclamide, dequalinium) delayed barrier recovery. Alterations in intracellular K+ regulated barrier homeostasis by either stimulating (reduced K+) or inhibiting (elevated K+) LB secretion. Finally, development of epidermal hyperplasia, a downstream consequence of barrier disruption, was also inhibited by agents that reduce intracellular K+ levels., Conclusions: These results demonstrate that changes in K+ levels that can be presumed to occur after barrier disruption signal metabolic responses, i.e. LB secretion, which accelerates normalization of barrier function.

Background: Previous studies have demonstrated that sex hormones modulate epidermal permeability barrier homeostasis, and when the balance of these hormones is altered at menopause or during the menstrual cycle, skin sensitivity or barrier function is changed., Objectives: To observe the direct effects of sex hormones on epidermal homeostasis., Methods: We examined the effects of topical application of sex hormones on permeability barrier recovery after tape stripping in the hairless mouse. To avoid the influence of systemic hormonal alteration, we employed male animals., Results: Application of androgen (testosterone or androsterone) delayed the barrier recovery, and the delay was overcome by co-application of beta-estradiol. Progesterone also delayed the barrier recovery, but in this case the delay was enhanced by beta-estradiol., Conclusions: These results suggest that changes in sex hormone balance might be associated with the skin dysfunction that often occurs during menopause, and at certain points during the menstrual cycle.

The 8 and 27 keV monoenergetic neutron calibration fields have been developed by using (45)Sc(p, n)(45)Ti reaction. Protons from a 4-MV Pelletron accelerator are used to bombard a thin scandium target evaporated onto a platinum disc. The proton energies are finely adjusted to the resonance to generate the 8 and 27 keV neutrons by applying a high voltage to the target assemblies. The neutron energies were measured using the time-of-flight method with a lithium glass scintillation detector. The neutron fluences at a calibration point located at 50 cm from the target were evaluated using Bonner spheres. A long counter was placed at 2.2 m from the target and at 60 degrees to the direction of the proton beam in order to monitor the fluence at the calibration point. Fluence and dose equivalent rates at the calibration point are sufficient to calibrate many types of the neutron survey metres.

Evaluation of the properties for quasi-monoenergetic neutron calibration fields of high energies more than 20 MeV at TIARA is proceeding for development of the field. Among the properties needed for the development as the standard calibration field, we report on measurement of the neutron beam profile using an imaging plate with a polyethylene converter and on estimation of the contribution of scattered neutrons into the irradiation field based on pulse height distribution at various off-beam positions measured using an organic liquid scintillation detector.

Natriuretic peptides (NPs) are a group of hormones playing important roles in cardiovascular and osmoregulatory systems in vertebrates. Among the NP subtypes, atrial NP (ANP), B-type NP (BNP), and ventricular NP (VNP) are circulating hormones expressed exclusively in the heart (cardiac NPs). The constitution of cardiac NPs is variable among species of vertebrates. In order to understand the evolutionary and functional significance of such variation, we performed a systematic survey of cardiac NP cDNAs in nine taxonomically diverse teleosts inhabiting environments of varying salinity. The discovery of the coexistence of the ANP, BNP, and VNP genes in the eel and rainbow trout suggested that the ancestral teleost had all three cardiac NPs. As the VNP cDNA was undetectable in ayu and six species of Neoteleostei, it is possible that VNP was lost before the divergence of Osmeroidei. The ANP gene was also undetectable in the medaka. Thus, only the BNP gene is universal in species examined in the present study. Synthetic medaka BNP preferentially activated two medaka GC-A-type receptors, suggesting that the three cardiac NPs share the same receptor. However, the regulation of BNP expression may be the most strict because ATTTA repeats in the 3'-untranslated region and the dibasic motif in the ring are conserved among teleosts and tetrapods. Linkage analyses in the rainbow trout located ANP, BNP, and VNP genes on the same chromosome, which suggested the generation of the VNP gene by tandem duplication as observed with ANP and BNP genes. If the duplication occurred before the divergence of tetrapods and teleosts, VNP may exist in the tetrapod lineage.

Twenty-one monkeys (cynomolgus, rhesus, African green) were fed cyclamate (100 mg/kg and 500 mg/kg) in the diet five times per week from a few days after birth and continuing for up to 24 years. Malignant tumors were diagnosed in three 24-year-old cyclamate monkeys; these were metastatic colon carcinoma (rhesus; 500 mg/kg), metastatic hepatocellular carcinoma (cynomolgus; 500 mg/kg), and a small, well differentiated adenocarcinoma of the prostate (cynomolgus; 100 mg/kg). Benign tumors were found at necropsy in three females; these were adenoma of the thyroid gland (rhesus; 100 mg/kg) and two cases of leiomyoma of the uterus (rhesus; 100 mg/kg and 500 mg/kg). No tumors were detected in an age-matched control group of 16 monkeys. Examination of the testes revealed complete testicular atrophy in one of the old cyclamate monkeys, and focal germ cell aplasia (Sertoli-only tubules) in two other cyclamate monkeys. Focal spermatogenic interruption (maturation arrest) at various germ cell levels mixed with normal spermatogenesis was observed in both the cyclamate-treated and the control monkeys, all of which were over 20 years old. Measurements of terminal cyclohexylamine concentrations showed that three of the males dosed with cyclamate at 500 mg/kg were high converters, with plasma concentrations comparable to the levels that produce testicular atrophy in rats. However, only one of the three high converters showed histologic evidence of irregular spermatogenesis. The overall conclusion is that the testicular abnormalities and the sporadic cases of different malignancies found after more than 20 years of dosing do not provide clear evidence of a toxic or carcinogenic effect of sodium cyclamate in monkeys.

Background: Angiogenesis is an essential factor for progression and metastases in solid tumors. It has been reported that several angiogenic factors play a role in the regulation of angiogenesis. Vascular endothelial growth factor (VEGF) is one of the most important molecules in angiogenesis. We investigated expressions of VEGF in a series of lung carcinomas with regard to clinicopathological factors., Method: VEGF expression was investigated by use of immunohistochemical studies and Northern blot analysis, using 155 primary and 26 metastatic lung carcinomas for the immunohistochemical studies and 10 primary and two metastatic lung carcinomas for the Northern blot analysis. All lesions were resected at surgery., Results: The frequencies for positive VEGF expression were 64 of 74 (86.5%) adenocarcinomas, 38 of 67 (56.7%) squamous cell carcinomas, four of four (100%) large cell carcinomas, two of three (66.7%) adenosquamous carcinomas and one of five (20%) small-cell carcinomas, the degree of positivity generally being greater in well differentiated tumors. The majority of metastatic foci from adenocarcinomas and squamous cell carcinomas at other sites were also positive (76.5 and 66.7%, respectively). VEGF expression did not correlate with clinicopathological factors such as tumor size or pathological stage, but pathological stage I adenocarcinoma cases positive for VEGF demonstrated a shorter disease-free period when followed up for 48 months than those cases expressing VEGF negatively., Conclusions: The results indicated that VEGF expression was frequently detected in non-small-cell lung cancers and suggested that VEGF might relate to the disease-free period of the patients with early adenocarcinomas.

The efficacy of combination therapy with cis-diammine-dichloroplatinum (II) (CDDP) and o-(chloroacetyl-carbamoyl) fumagillol (AGM-1470) was evaluated experimentally using a transplantable rat osteosarcoma line, previously established in our laboratory, with a high potential for metastasis. Tumor-bearing male Fischer 344 rats were administered CDDP (2.5 mg/kg) together with, or after discontinuation of, AGM-1470 treatment (10 mg/kg/body weight/week). When CDDP was administered three days after discontinuation of AGM-1470 the most pronounced antimetastatic effects were observed, although the antitumor effect was approximately the same.

A case of Ki-1-positive anaplastic large cell lymphoma of the pancreas is presented. The patient complained of abdominal pain and was jaundiced. Examination of a biopsy specimen obtained by duodenal endoscopy revealed malignant lymphoma, and surgery confirmed a large mass located in the region from the intra-pancreatic tissue around the lower common bile duct to the peri-pancreatic lymph nodes. Histologically, this tumor was composed mainly of large and giant neoplastic cells. Immunohistochemically, these cells were diffusely positive for Ki-1 and CD45RO antigens, indicating the features of Ki-1 anaplastic large cell lymphoma with a T-cell phenotype among non-Hodgkin's lymphoma. The histologic types of the majority of malignant lymphomas of the pancreas reported previously were considered to be diffuse-type non-Hodgkin lymphoma (probably with predominance of the B-cell phenotype), except for a single Japanese lymphoma case with a T-cell phenotype. This is therefore the first known case of Ki-1 anaplastic large cell lymphoma of the pancreas.

We suggested for the introduction of a prolyl residue into a protein that if the N-terminus residue is glycine, an unfavorable interaction in the folded state caused by the introduction of the prolyl residue can be substantially avoided by use of mutant lysozymes in which Gly-Pro and Pro-Gly sequences are introduced to positions 101-102 in the loop region of the lysozymes [Ueda, T., Tamura, T., Maeda, Y., Hashimoto, Y., Miki, T., Yamada, H., and Imoto, T. (1993) Protein Eng. 6, 183-187]. In order to determine whether or not the information obtained is applicable to other regions, we prepared mutant lysozymes with Gly-Pro and Pro-Gly sequences at position 47, which is located in the beta-sheet, positions 70-71, which are located in the loop, positions 117-118, which are located in the beta-turn, and positions 121-122, which are located in the 3(10)-helix. The free energy changes of the native and mutant lysozymes for unfolding were determined at pH 5.5 and 35 degrees C. However, a mutant lysozyme with the Gly-Pro sequence was not always stabler than that with the Pro-Gly sequence at the same site. On the other hand, in order to determine whether or not strain caused by these sequences exists in the folded or unfolded state, the structures of these mutant lysozymes were determined by use of energy minimization. On comparison of the differences in the free energy change between the mutant lysozymes with Gly-Pro and Pro-Gly sequences at the same site with those in their total local conformational energies, it was found there is a good correlation between them. Therefore, it was suggested that the difference in total local conformational energy caused by the introduction of a Gly-Pro or Pro-Gly sequence could be estimated by use of the energy minimized structure. Moreover, the correlation indicated that the differences in the free energy change between Gly-Pro and Pro-Gly lysozymes may be reflected by the differences in the total local conformational energies in their folded state. It was suggested that the energy levels in the unfolded states of mutant lysozymes with Gly-Pro and Pro-Gly sequences at the same site in a Gdn-HCl solution were almost identical.

The efficacy of the anti-angiogenic agent, O-(chloroacetyl-carbamoyl)fumagillol (AGM-1470), against primary tumor growth and spontaneous lung metastasis was evaluated experimentally using a transplantable osteosarcoma line in rats previously established in our laboratory. Male Fischer 344 rats bearing the tumor with a high potential for metastasis received intermittent or continuous subcutaneous administrations of AGM-1470. Both treatment regimens resulted in significant inhibitions of spontaneous lung metastasis and primary tumor growth in a dose-dependent manner, with continuous administration of AGM-1470 exerting the most pronounced inhibitory effects on both parameters.

Prolonged exposure of the GnRH receptor to high concentrations of GnRH leads to receptor down-regulation. The role of altered receptor biosynthesis in this agonist-induced receptor down-regulation was investigated in the mouse gonadotrope cell line, alpha T3-1 cells. After exposure to 1 microM GnRH for 24 h, the number of GnRH receptor-binding sites in alpha T3-1 cells decreased to 25 +/- 6% of the control levels. No corresponding changes were observed in GnRH receptor messenger RNA (mRNA) using either quantitative ribonuclease protection/solution hybridization assay or Northern blot analysis. However, when the ability of this RNA to direct the synthesis of functional GnRH receptors was examined by quantitative assessment of the voltage clamp response in Xenopus oocytes, GnRH-induced currents in oocytes injected with RNA isolated from down-regulated cells was reduced to 40 +/- 13% of the response obtained after the injection of RNA from control alpha T3-1 cells. Thus, although GnRH receptor mRNA levels were not altered, the ability of cellular RNA isolated from alpha T3-1 cells to direct the synthesis of functional GnRH receptors was regulated in concert with receptor binding. To investigate the possibility that GnRH receptor mRNA translational efficiency was reduced, the distribution of polyribosome-associated GnRH receptor mRNA was studied. Polyribosome-associated mRNA was separated by linear sucrose gradient, and GnRH receptor mRNA distribution was determined by ribonuclease protection assay. GnRH receptor mRNA distribution shifted from the largest to smaller polyribosome and monosome fractions in cells exposed to GnRH compared to controls. The weighted mean of GnRH receptor mRNA distribution among eight fractions shifted from fraction 5.924 +/- 0.06 in control polysomes to fraction 5.45 +/- 0.219 for polysomes from down-regulated cells (P < 0.05). These results demonstrate that GnRH receptor down-regulation is accompanied by decreased GnRH receptor mRNA translation in the absence of any change in GnRH receptor mRNA levels. These data suggest that decreased efficiency of GnRH receptor mRNA translation contributes to the down-regulation of this receptor in alpha T3-1 cells.

The presence of the Ki-ras gene mutations in 14 cases of intrahepatic cholangiocarcinoma (IHC) and nine cases of extrahepatic cholangiocarcinoma (EHC) were investigated by polymerase chain reaction-single strand conformation polymorphism analysis. To obtain enriched tumor cell DNA, the microdissection method was used on formalin-fixed paraffin-embedded tissue sections. Point mutations at codon 12 of the Ki-ras gene were detected in seven (50%) of the 14 cases of IHC and six (67%) of the nine EHC cases. In all but one of the ras gene mutation cases, G to A transitions in the second position of codon 12 were detected, the exception being a G to T transition in the same position in one IHC. No point mutations were detected at codon 13 or 61 in either IHC or EHC. Furthermore, there was no demonstrable correlation between Ki-ras mutation and patient age, tumor Stage, histological findings or prognosis. The present results demonstrated a higher participation of Ki-ras gene mutations in EHC than found in previous studies, and provided a confirmation and extension of the results earlier reported by Tada et al. and Tsuda et al. for IHC.

Genetic factors related to the development of alcoholic liver and pancreatic diseases (ALD and APD) and of alcohol-induced asthma were analyzed. The development of ALD is genetically controlled and is directly associated with the polymorphisms of the genes of acetaldehyde (Ac-CHO) and ethanol-metabolizing enzymes, aldehyde dehydrogenase-2 (ALDH2) and cytochrome P4502E1. The development of ALD and APD may also be genetically linked with the induction of gamma-glutamyl transferase (GTT) by alcohol. Alcohol-induced asthma is related to the genotypes of ALDH2 and is caused by rapid elevation of blood Ac-CHO. ALDH1 plays a very important role in the oxidation of Ac-CHO in blood.

Since heavy drinkers do not always develop alcoholic liver disease (ALD), genetic factors may be involved. Cytochrome P4502E1 (P4502E1) is the main enzyme that oxidizes ethanol in the non-alcohol dehydrogenase pathway. Recently, the presence of genetic polymorphisms at the 5'-flanking region of this enzyme was confirmed. We recently detected the c2 gene of P4502E1 in most patients with ALD, suggesting that development of ALD may be genetically controlled. Although high transcriptional activity of the c2 gene was confirmed in studies using the Hep G2 cell, little is known about transcriptional activity in humans with the c2 gene. Therefore, messenger RNA (mRNA) contents of P4502E1 in livers of patients with different P4502E1 genotypes were measured. Hepatic mRNA contents in type B were three times higher than in type A, suggesting that transcriptional activity of the c2 gene of P4502E1 is stronger than that of the c1 gene, even in human liver. The results of the present study are compatible with those in the Hep G2 cells. These results suggest that polymorphisms of the P4502E1 gene may be linked to the development of ALD through enhancement of ethanol metabolism in the non-alcohol dehydrogenase pathway.

A 60-year-old male with a small cell carcinoma of the right lower ureter is presented. The tumor mainly comprised a small cell carcinoma but also included a full variety of histological types such as transitional cell carcinoma, squamous cell carcinoma, adenocarcinoma, leiomyosarcoma and chondrosarcoma. Immunohistochemical staining was positive for neuron specific enolase and cluster 1 small cell lung cancer antigen/N-CAM in the small cell carcinoma and S-100 in the chondrosarcoma component. The patient underwent a right nephroureterectomy, and received prophylactic radiation of the pelvic and para-aortic lymph node regions and cisplatin and etoposide combination chemotherapy. Eight months after the chemotherapy, a transitional cell carcinoma was found in the bladder neck, and a cystectomy with urethrectomy performed. To our knowledge, this is the second report of a small cell carcinoma originating from the ureter.

We studied the effect of brotizolam (BRO) (0.25 mg) and zopiclone (ZPC) (7.5 mg) on the sleep electroencephalograms (EEG) of seven healthy young women (ages 20-21 years). In addition to conventional sleep scoring, we performed spectral analysis of EEG wave forms using the Fast Fourier Transformation (FFT) method. Four weeks following two consecutive polysomnographic recordings with placebo administration (for baseline data), polysomnography with BRO or ZPC administration was performed on the subjects who were then crossed over to polysomnography with ZPC or BRO, respectively, 1 week later. Total rapid eye movement (REM) time was decreased on the ZPC and BRO nights and REM latency was prolonged on the ZPC night compared with baseline (BL) night. Other parameters, however, were not significantly different between the drug nights and the BL night. There were also no differences in standard scoring results between both drug nights. FFT analysis revealed significant differences in total power density percentage and mean power density percentage in both nonrapid eye movement (NREM) and REM sleep between ZPC and BRO nights and between both drug nights compared to the BL night. Total power density and mean power density per epoch showed significant decreases in the theta band (6.0-8.0 Hz) and sigma band (12.0-14.0 Hz) on the ZPC night versus the BRO night or BL night during specific NREM periods. The results of this study corroborate previous reports that suggest computer-aided quantitative electroencephalography aids in differentiating specific effects of hypnotics and other central-nervous-system-acting agents on the sleep EEG.(ABSTRACT TRUNCATED AT 250 WORDS)

Characteristic histological features of alcoholic liver disease (ALD) are pericellular and perivenular fibrosis. It has been emphasized from immunohistochemical studies that pericellular and perivenular fibrosis may be caused by the increase of type IV collagen (IV-C) and/or laminin (LM). However, quantitative changes of hepatic IV-C and LM contents in ALD are not well known. Recently, we have developed assay systems for IV-C and LM contents in liver biopsy specimens. In the present study, hepatic IV-C and LM contents in ALD and non-ALD patients were measured. Liver biopsy specimens were obtained from 36 patients with ALD, 24 patients with non-ALD and five patients without liver disease. IV-C and LM contents in liver biopsy specimens were measured using the one-step sandwich enzyme immunoassay system for human serum IV-C and LM levels. Total collagen (T-C) content was also measured by the method of Leon and Rojkind. Hepatic IV-C, LM and T-C contents were significantly higher in all types of liver disease than in controls, and tended to increase with the progression of fibrosis. Especially in ALD, both IV-C and LM contents increased from the early stage, and the values in each type of ALD were significantly higher than those in the corresponding type of non-ALD. The ratio of IV-C or LM to T-C was also significantly higher in ALD than in the corresponding non-ALD. The prominent increases of IV-C and LM at the early stage of fibrosis may be one of the characteristics of collagen metabolism in ALD.(ABSTRACT TRUNCATED AT 250 WORDS)

It has been reported that microheterogeneity of serum glycoproteins including transferrin is found in alcoholic liver disease. In the present study, microheterogeneity of serum glycoproteins in alcoholic liver disease patients was analysed using the Western blotting technique after isoelectric focusing. Microheterogeneity was found for serum alpha 1-antitrypsin, alpha 2-macroglobulin, caeruloplasmin, alpha 1-acid glycoprotein and hemopexin as well as transferrin. Microheterogeneity disappeared following treatment with sialidase in some but not all glycoproteins. In hemopexin, microheterogeneity was recognized only after treatment with sialidase. These results suggest that mechanisms of microheterogeneity of serum glycoproteins in alcoholic liver disease may vary. One mechanism may be the interference of glycosylation of glycoproteins in the Golgi apparatus, and another may be the decrease of asialo-protein receptors in hepatocytes.

It has been reported that basement membranes were found around the sinusoidal walls in cirrhotic livers, indicating the development of capillarization of the sinusoids. It has been also emphasized that capillarization of the sinusoids is more prominent in alcoholic liver disease (ALD). In the present study, factor VIII related antigen (VIII-Ag) and UEA-1 were identified immunohistochemically in order to analyze capillarization of the sinusoids in chronic liver diseases. Electron microscopic studies on the endothelial cells and sinusoids were also performed. Electron microscopic studies revealed that the number of fenestra in the endothelial cells decreased and basement membranes were clearly observed in the space of Disse from an early stage of ALD. However, these changes were not observed in the early stage of non-ALD. VIII-Ag or UEA-1 was not stainable in the sinusoidal cells of normal livers or at an early stage of non-ALD. However, in ALD, both VIII-Ag and UEA-1 were clearly demonstrated in the sinusoidal cells from the early stage of fibrosis. These results suggest that the sinusoidal endothelial cells may transform to vascular endothelial cells from an early stage of ALD. The alterations in the sinusoidal endothelium and the basement membrane formation in the Disse space indicate that capillarization of the sinusoid may occur. Capillarization of the sinusoid may cause a disturbance in exchanges of many bioactive substances between the sinusoidal blood and hepatocytes across the Disse space and may thereby contribute to the pathogenesis of ALD.

The high prevalence of hepatitis C virus (HCV) markers in alcoholic liver cirrhosis (AL-LC) and hepatocellular carcinoma (HCC) suggests a close aetiopathogenic relationship between alcoholic liver disease (ALD) and HCV infection. In the present study, HCV markers in ALD were measured by the highly sensitive methods, and the changes of sequential HCV markers after abstinence in ALD patients were analysed in order to elucidate the effect of alcohol on HCV. Antibodies to HCV-related antigen were determined using the first or second generation test kit. HCV-RNA genomes encoding the NS-5 region were detected using the RT-PCR method. In the HCV-NS5 negative serum, HCV genomes of the 5'-noncoding region were detected using the two-stage PCR method. Titres of HCV-RNA were measured by multiple cyclic PCR and cDNA dot blotting. Typing of HCV genomes was carried out on the PCR product from the NS-5 region by slot blot hybridization using type-specific cDNA probes, or by restriction fragment length polymorphisms analysis. In alcoholic fibrosis and alcoholic hepatitis, the prevalence of HCV markers was low, suggesting that the main aetiological factor is alcohol but not HCV in these types of ALD. HCV markers were positive in the half of the patients with AL-LC, and in more than 80% of patients with AL-CH and AL-HCC, indicating that HCV infection closely relates to these types of ALD. The ratio of the K1 type to the K2 type of HCV genomes was 4:1 in all types of NANB liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Heavy drinkers do not always develop alcoholic liver disease or cancer of the digestive organs, indicating that genetic factors may be involved. Recently, the presence of genetic polymorphisms of cytochrome P4502E1 (2E1) was confirmed. The genotype of 2E1 was separated into three types; type A which is homozygous for the c1 gene, type B which is heterozygous for the c1 and c2 genes, and type C which is homozygous for the c2 genes. In the present study the relationship between genotypes of 2E1 and digestive diseases, including alcoholic liver disease, was analyzed. In healthy controls, the prevalence of types A, B and C was 69%, 31% and 0%, respectively. In patients with esophageal cancer, four out of five patients (80%) were type B, and the prevalence of type B was significantly higher than that in normal controls. These results suggest that the c2 gene of 2E1 may be related to the development of esophageal cancer. In patients with gastric disease, the prevalence of types A and B was 72% and 28%, respectively. In patients with large bowel disease, the prevalence of type A was 83-100%, significantly higher than that in healthy controls. These results suggest that the c2 gene of 2E1 may not be related to the development of large bowel disease. However, the possibility should be considered that the c1 gene of 2E1 may link to its development. In this study, the relationship between the genotype of 2E1 and alcoholic liver disease was also analyzed. All patients with alcoholic liver disease, including one hepatoma, had the c2 gene but not the c1 gene. The frequency of the c2 gene was quite different from that in non-alcoholic liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

At least four types of aldehyde dehydrogenase (ALDH) isozymes exist in human liver: acetaldehyde (Ac-CHO) is metabolized mainly by ALDH2. However, the role of ALDH1 in Ac-CHO metabolism is not well known, because ALDH1 deficiency is rare. In the present study, changes in blood levels of Ac-CHO were analyzed in a person with ALDH1 deficiency who is also heterozygous for the ALDH2 alleles, and subjects with normal ALDH1, in order to clarify the roles of ALDH1 in the metabolism of Ac-CHO. By isoelectric focusing analysis of ALDH in red blood cells (RBC), the ALDH1 band was not detectable in a male subject, indicating ALDH1 deficiency. In this subject, ALDH1 activity was nearly null, but the activities in his wife and two children were normal. Serial changes of blood Ac-CHO levels following a small amount of ethanol were analyzed. The peak levels of Ac-CHO were not different between the subject with ALDH1 deficiency and the person with normal ALDH1. However, the decrease from the peak values of Ac-CHO was clearly slower in the deficient subject than in ALDH1 normal subjects. Changes in Ac-CHO in blood were also analyzed in vitro. Ac-CHO metabolism by RBC from the ALDH1 deficient subjects was clearly slower than in those from controls. These results indicate that ALDH1 plays an important role in the metabolism of Ac-CHO in blood.

To assess the temporal changes of the pancreatic duct following the administration of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) in two dogs, serial pancreatography was performed. They received intraductal administration of a total of 595 and 500 mg ENNG in each one, over the periods of 12 and 13.5 months, respectively. In one dog, sequential changes of the main duct were observed, a small round filling defect developed a circumferential defect and became a severe stenosis associated with proximal dilatation of the duct. While no gross tumors were macroscopically detected at autopsy, continuous lesions with features of hyperplasia, atypical hyperplasia, and cancerous change of duct epithelial cells were microscopically seen. In the other one, a small round filling defect was detected by pancreatography, which was histopathologically hyperplasia of pancreatic duct, rather than cancerous cells. The present dog model for induction of pancreatic duct carcinomas appears useful for elucidating clinico-pathological changes occurring during cancer development.

The multiplicity of transitional cell carcinomas in the renal pelvis, ureter and bladder was analyzed in terms of (1) tumor configuration, i.e., papillary, nodular cancers, (2) associated mucosal changes such as carcinoma in situ (CIS) and dysplasia and (3) the possible involvement of human papillomavirus (HPV) in the development of multiple papillary cancers in the bladder. The incidences of concurrent or subsequent bladder cancer in renal pelvic cancer and/or ureteral cancer cases were 7/31 (22%) for renal pelvic cancer, 17/28 (60%) for ureteral cancer and 10/15 (67%) for renal pelvic and ureteral cancer. In 33 cases of renal pelvic and/or ureteral cancer occurring since 1978, 67% of the papillary and 13% of the nodular cancers in the upper tract exhibited a simultaneous or later development of bladder cancer. In 211 cases of bladder cancer for which cystectomy was performed, 77% of the papillary cancers arose in multiple form, 57% being associated with CIS and/or dysplasia, whereas 72% of the nodular cancers developed singly, 55% being associated with CIS and/or dysplasia. No positive signals hybridizing to HPV types 1, 5, 6, 11, 16, 17, 18, 20, 33 and 38 were detected in any of 19 papillary bladder cancers and 13 specimens of normal bladder mucosa under conditions of low stringency, suggesting that HPV may not be a factor in multiple bladder tumor development. Definite findings from the present study are: (1) there is multiple development of papillary cancers but they remain superficial, whereas nodular cancers develop singly and are invasive, (2)) there was no steady tendency towards a relation between multiplicity and associated mucosal changes, (3) HPV was not, to our knowledge, involved in the multiple development of papillary cancers in the bladder.

An allergenic pentasaccharitol, Gp-1 beta-b6, was isolated as a minimum structural unit responsible for the allergic reaction in skin of patients with sea squirt allergy from a saccharitol fraction, Gp-1 beta-b, that had been liberated by beta-elimination from a glycopeptide in a Pronase digest of a sea squirt antigen, Gi-rep. Methylation/GC-MS and FAB-MS analyses indicated the sugar sequence of Gp-1 beta-b6 to be GalNAcl----2Fucl----(GalNAc1----) 3,4GlcNAc1----3GalNAc-ol. To analyze the structure in more detail, Gp-1 beta-b6 was labeled with p-aminobenzoic acid ethyl ester (ABEE), i.e., the reducing terminal 3-O-substituted GalNAc-ol of the saccharitol was oxidized to 2-O-substituted L-ThrNAc with equimolar periodate, and the resultant aldehyde was labeled with ABEE by reductive amination. The ABEE-labeled Gp-1 beta-b6 was subjected to sequential exoglycosidase digestion with beta-N-acetylhexosaminidase, alpha-N-acetylgalactosaminidase, and alpha-fucosidase, and the digests were chromatographed on an HPLC column of TSK gel Amide 80. From the results of the HPLC, methylation/GC-MS, and FAB-MS analyses of the digests of the labeled substrate, the structure of Gp-1 beta-b6 was determined to be GalNAc alpha 1----2Fuc alpha 1----3(GalNAc beta 1----4)GlcNAc beta 1----3GalNAc-ol. Enzymatic elimination of either the non-reducing terminal beta-GalNAc or the non-reducing terminal alpha-GalNAc led to inactivation of the allergenic pentasaccharitol. Accordingly, it is possible that the allergenic saccharitol contains two disaccharide units as the allergy-specific epitopes, one GalNAc alpha 1----2Fuc alpha 1---- and the other GlcNAc beta 1----4GLcNAc beta 1----.

A rapid-production model incorporating the principle of selection by resistance to cytotoxicity demonstrated earlier for liver carcinogenesis in rats was established for pancreatic carcinoma development in Syrian hamsters. Adenocarcinomas were induced in 84% of treated animals by 10 weeks after initiation with 70 mg of N-nitroso-bis(2-oxopropyl)amine (BOP) per kg of body weight when augmentation pressure (choline-deficient diet combined with DL-ethionine and L-methionine and administration of 20 mg/kg BOP upon return to basal diet) was applied three times. A 52% yield of cholangiocellular tumors also resulted from this experimental protocol.

We used 29 polymorphic DNA markers to analyze tumor DNA samples from six patients with sporadic pheochromocytoma for possible loss of chromosomal heterozygosity; four had benign disease and two had malignant disease. Loss of heterozygosity was observed on four chromosomes: 1p (three of four patients), 2p (one of one), 5q (two of six), and 11p (three of five). Chromosomes 1p and 11p frequently had allelic deletions in these tumors, and these deletions may play an important role in the development of pheochromocytoma.

A new perfusion system of isolated rat femora was established, and the effect of PTH or calcitonin (CT) on cAMP release from the adult bone was examined. Stimulation of cAMP release from the isolated perfused bone peaked rapidly between 5 and 10 min after human PTH (hPTH)-(1-34) or eel CT injection, respectively, and declined gradually toward the preinjection level. However CT exhibited a longer lived effect than PTH. Release of cAMP was still significantly greater than control at 60 min after a bolus injection of CT. The rate of cAMP release was directly related to the dose of PTH or CT. H2O2-oxidized PTH (biologically inactive) caused no increase in cAMP release. hPTH-(1-34) was markedly more potent than hPTH-(1-84) in stimulating cAMP release from the perfused bone on an equimolar basis. Simultaneous administration of 5 micrograms PTH and 5 micrograms CT at maximal stimulatory doses produced additive effects, indicating the presence of separate receptor sites for PTH and CT in the bone. In conclusion, this system provides us a means by which hormone actions on adult bone with integrity of the organ can be evaluated and therefore makes possible systemic investigation of the osteoblast-osteoclast function.

The present studies were designed to explore the mechanism underlying skeletal refractoriness to PTH in a vitamin D-deficient animal by assessment of PTH-stimulated cAMP release from isolated perfused bone. In vitamin D-deficient (-D) rats both basal and PTH-stimulated cAMP release were markedly diminished, compared with that in vitamin D-replete (+D) rats. Isolated perfused bones from -D rats that had undergone parathyroidectomy 2 days before death still showed reduced cAMP release in response to PTH, compared with +D bones. To investigate which factors in terms of Ca, endogenous PTH, or vitamin D might primarily be responsible for the impaired PTH-stimulated cAMP release from -D bones, some -D rats were switched to a diet identical to the vitamin D-deficient diet but with high Ca content (4%) for 2 or 5 weeks before death. This schedule maintained normocalcemia despite vitamin D deficiency. PTH-stimulated cAMP release in these rats was increased to a level intermediate between that in -D rats and +D rats, indicating partial restoration of the impaired response to PTH in -D rats. These data indicate that skeletal refractoriness to PTH in vitamin D-deficient animals might, in part, be due to the impaired activation of adenylate cyclase, which cannot be explained entirely by hypocalcemia or associated secondary hyperparathyroidism. Vitamin D deficiency per se, therefore, may play a key role in the impaired cAMP response to PTH.

Although more than 50 patients with the tumor-induced osteomalacia syndrome, characterized by remission of unexplained osteomalacia after resection of a coexisting tumor, have been reported, the pathogenesis of this syndrome is still not clear. We investigated the cause of biopsy-confirmed osteomalacia which was resistant to treatment with 1 alpha-hydroxyvitamin D3 in a 54-yr-old man. He had severe hypophosphatemia, a high serum alkaline phosphatase level, a low plasma 1,25-dihydroxyvitamin D level, and remarkably increased urinary phosphorus excretion. A tumor, with histological characteristics of a hemangiopericytoma, was found on his left thigh. After surgical removal of this tumor, his plasma 1,25-dihydroxyvitamin D and serum phosphorus levels increased to normal levels, and his bone pain subsided. The tumor was transplanted to athymic nude mice. A nodule formed in each mouse, with histological features identical to those of the original tumor, and the tumor-bearing mice had hypophosphatemia, high serum alkaline phosphatase levels, and increased urinary phosphorus excretion. When extracts of the original tumor were added to primary cultures of renal tubular cells, renal cAMP levels did not change, but 25-hydroxyvitamin D-1 alpha-hydroxylase activity was significantly inhibited. These data indicate tumoral production of some humoral factor(s) inhibiting 25-hydroxyvitamin D-1 alpha-hydroxylase activity and phosphorus reabsorption unrelated to adenylate cyclase-cAMP production in proximal renal tubules.