Molecular evolution of catalytic antibodies in autoimmune mice

Catalytic Abs (catAbs) preferentially evolved in autoimmune MRL/MPJ-lpr/lpr (MRL/lpr) mice upon immunization with the phosphonate transition-state analogue (TSA), but this did not happen in normal BALB/c mice. The majority of the catAbs from MRL/lpr mice were from several independent clones of the same family. Most of them had a lysine at position 95 in the heavy chain (H95), which is at the junctional region. This residue, which interacts with the phosphonate moiety of the TSA and presumably is involved in the catalytic activity, was not changed even after expansive evolution following multiple mutations. By contrast, the majority that arose from BALB/c mice were the non-catAbs, which were quite different in the sequence from the catAbs from MRL/lpr mice, but they were clonally related to one another, so most of them were originated from a single clone. In the MRL/lpr mice, the catalytic subsets that existed in the initial repertoire were effectively captured by the phosphonyl oxygens in the TSA by interacting with the lysine at H95. In the BALB/c mice, however, another noncatalytic subset with only the binding capability directed to a moiety other than the phosphonate moiety was alternatively evolved, because of the lowest abundance or elimination of the catalytic subsets.

Ectopic expression of DREF induces DNA synthesis, apoptosis, and unusual morphogenesis in the Drosophila eye imaginal disc: possible interaction with Polycomb and trithorax group proteins

The promoters of Drosophila genes encoding DNA replication-related proteins contain transcription regulatory element DRE (5'-TATCGATA) in addition to E2F recognition sites. A specific DRE-binding factor, DREF, positively regulates DRE-containing genes. In addition, it has been reported that DREF can bind to a sequence in the hsp70 scs' chromatin boundary element that is also recognized by boundary element-associated factor, and thus DREF may participate in regulating insulator activity. To examine DREF function in vivo, we established transgenic flies in which ectopic expression of DREF was targeted to the eye imaginal discs. Adult flies expressing DREF exhibited a severe rough eye phenotype. Expression of DREF induced ectopic DNA synthesis in the cells behind the morphogenetic furrow, which are normally postmitotic, and abolished photoreceptor specifications of R1, R6, and R7. Furthermore, DREF expression caused apoptosis in the imaginal disc cells in the region where commitment to R1/R6 cells takes place, suggesting that failure of differentiation of R1/R6 photoreceptor cells might cause apoptosis. The DREF-induced rough eye phenotype was suppressed by a half-dose reduction of the E2F gene, one of the genes regulated by DREF, indicating that the DREF overexpression phenotype is useful to screen for modifiers of DREF activity. Among Polycomb/trithorax group genes, we found that a half-dose reduction of some of the trithorax group genes involved in determining chromatin structure or chromatin remodeling (brahma, moira, and osa) significantly suppressed and that reduction of Distal-less enhanced the DREF-induced rough eye phenotype. The results suggest a possibility that DREF activity might be regulated by protein complexes that play a role in modulating chromatin structure. Genetic crosses of transgenic flies expressing DREF to a collection of Drosophila deficiency stocks allowed us to identify several genomic regions, deletions of which caused enhancement or suppression of the DREF-induced rough eye phenotype. These deletions should be useful to identify novel targets of DREF and its positive or negative regulators.

Turner syndrome and Xp deletions: clinical and molecular studies in 47 patients

Although clinical features of Turner syndrome have primarily been explained by the dosage effects of SHOX (short stature homeobox-containing gene) and the putative lymphogenic gene together with chromosomal effects leading to nonspecific features, several matters remain to be determined, including modifying factors for the effects of SHOX haploinsufficiency, chromosomal location of the lymphogenic gene, and genetic factors for miscellaneous features such as multiple pigmented nevi. To clarify such unresolved issues, we examined clinical findings in 47 patients with molecularly defined Xp deletion chromosomes accompanied by the breakpoints on Xp21-22 (group 1; n = 19), those accompanied by the breakpoints on Xp11 (group 2; n = 16), i(Xq) or idic(X)(p11) chromosomes (group 3; n = 8), and interstitial Xp deletion chromosomes (group 4; n = 4). The deletion size of each patient was determined by fluorescence in situ hybridization and microsatellite analyses for 38 Xp loci including SHOX, which was deleted in groups 1-3 and preserved in group 4. The mean GH-untreated adult height was -2.2 SD in group 1 and -2.7 SD in group 2 (GH-untreated adult heights were scanty in group 3). The prevalence of spontaneous breast development in patients aged 12.8 yr or more (mean +/- 2 SD for B2 stage) was 11 of 11 in group 1, 7 of 12 in group 2, and 1 of 7 in group 3. The prevalence of wrist abnormality suggestive of Madelung deformity was 8 of 18 in group 1 and 2 of 23 in groups 2 and 3, and 9 of 18 in patients with spontaneous puberty and 1 of 23 in those without spontaneous puberty. The prevalence of short neck was 1 of 19 in group 1 and 7 of 24 in groups 2 and 3. Soft tissue and visceral anomalies were absent in group 1 preserving the region proximal to Duchenne muscular dystrophy and were often present in groups 2 and 3 missing the region distal to monoamine oxidase A (MAOA). Multiple pigmented nevi were observed in groups 1-3, with the prevalence of 0 of 7 in patients less than 10 yr of age and 15 of 36 in those 10 yr or older regardless of the presence or absence of spontaneous puberty. Turner phenotype was absent in group 4, including a fetus aborted at 21 wk gestation who preserved the region distal to MAOA. The results provide further support for the idea that clinical features in X chromosome aberrations are primarily explained by haploinsufficiency of SHOX and the lymphogenic gene and by the extent of chromosome imbalance in mitotic cells and pairing failure in meiotic cells. Furthermore, it is suggested that 1) expressivity of SHOX haploinsufficiency in the limb and faciocervical regions is primarily influenced by gonadal function status and the presence or absence of the lymphogenic gene, respectively; 2) the lymphogenic gene for soft tissue and visceral stigmata is located between Duchenne muscular dystrophy and MAOA; and 3) multiple pigmented nevi may primarily be ascribed to cooperation between a hitherto unknown genetic factor and an age-dependent factor other than gonadal E.

Ectopic expression of BEAF32A in the Drosophila eye imaginal disc inhibits differentiation of photoreceptor cells and induces apoptosis

Transgenic flies were established in which ectopic expression of boundary element-associated factor (BEAF) 32A was targeted to the Drosophila eye imaginal disc. The eyes of the adult fly displayed a severe rough eye phenotype. When these eyes were sectioned, most ommatidia were found to be fused and irregularly shaped rhabdomeres were observed. In the developing eye imaginal disc, expression of BEAF32A inhibited differentiation of photoreceptor cells. Expression of BEAF32A also induced extensive apoptosis of eye imaginal disc cells and, consistent with this, co-expression of baculovirus P35 in the eye imaginal disc suppressed the BEAF32A-induced rough eye phenotype. To investigate the effects of BEAF32A on regulation of chromatin structure, genetic crosses of the BEAF32A-overexpressing flies with loss-of-function mutants for genes encoding other boundary element-binding factors or regulators of chromatin structure were conducted. Interestingly, half-dose reduction of the su(Hw) gene strongly enhanced the rough eye phenotype induced by BEAF32A. Furthermore, genetic crosses of the transgenic flies with loss-of-function mutants for genes interacting with Polycomb revealed specific links between BEAF32A and genes such as Distalless and kohtalo, suggesting a relation to the chromatin insulator function of BEAF. In addition, genetic crosses of transgenic flies expressing BEAF32A with a collection of Drosophila deficiency stocks allowed us to identify several genomic regions, deletions of which caused enhancement or suppression of the BEAF32A-induced rough eye phenotype. The transgenic flies established in this study should be useful to identify targets of BEAF32A and its positive or negative regulators in Drosophila.

Dependence on the sample width of signals from a near-field optical microscope

We numerically investigated signals from a scanning near-field optical microscope (NOM) for samples of various sizes by using the finite-difference time-domain method. Under the usual conditions that apply to detection, the signal intensity depends on the width of the sample, even though the sample will be wider than the wavelength, which is much larger than the aperture, i.e., the lateral resolution of the NOM. This is an obstacle to measuring the local optical constant of samples by means of obtaining the signal intensity. When waves propagating in all directions are collected, this dependence on the sample width is reduced. The whole angle detection is important for observing the distribution of the optical constants.

The preparation and crystallization of Fab fragments of a family of mouse esterolytic catalytic antibodies and their complexes with a transition-state analogue

The Fab fragments of a family of mouse esterolytic monoclonal antibodies MS6-12, MS6-126 and MS6-164 have been obtained by digestion of whole antibodies with papain, purified and crystallized in a range of different forms either alone or in complex with a transition-state analogue. The crystals diffract X-rays to resolutions between 2.1 and 1.2 A and are suitable for structural studies. The determination of these structures could be important in understanding the different catalytic power of each of these related catalytic antibodies.

Saturated FFAs, palmitic acid and stearic acid, induce apoptosis in human granulosa cells

Obesity is associated with insulin resistance and some reproductive abnormalities. Circulating FFAs are often elevated in obese subjects and are also closely linked to insulin resistance. In this study, we demonstrated that saturated FFAs, such as palmitic acid and stearic acid, markedly suppressed the granulosa cell survival in a time- and dose-dependent manner. Polyunsaturated FFA, arachidonic acid, had no effect on the cell survival, even at supraphysiological concentrations. The suppressive effect of saturated FFAs on cell survival was caused by apoptosis, as evidenced by DNA ladder formation and annexin V-EGFP/propidium iodide staining of the cells. The apoptotic effects of palmitic acid and stearic acid were unrelated to the increase of ceramide generation or nitric oxide production and were also completely blocked by Triacsin C, an inhibitor of acylcoenzyme A synthetase. In addition, acylcoenzyme A, pamitoylcoenzyme A, and stearylcoenzyme A markedly suppressed granulosa cell survival, whereas arachidonoylcoenzyme A had no such effect, and this finding was consistent with the effect of the respective FFA form. Surprisingly, arachidonic acid instead showed a protective effect on palmitic acid- and stearic acid-induced cell apoptosis. A Western blot analysis showed the apoptosis of the granulosa cells induced by palmitic acid to be accompanied by the down-regulation of an apoptosis inhibitor, Bcl-2, and the up-regulation of an apoptosis effector, Bax. These results indicate that saturated FFAs induce apoptosis in human granulosa cells caused by the metabolism of the respective acylcoenzyme A form, and the actual composition of circulating FFAs may thus play a critical role in the apoptotic events of human granulosa cells. These effects of FFAs on granulosa cell survival may be a possible mechanism for reproductive abnormalities, such as amenorrhea, which is frequently observed in obese women.

[Neoral (Cyclosporin microemulsion preconcentrate): pharmacokinetics, pharmacodynamics and its improved clinical outcome]

Sandimmun displays considerable inter- and intra-patient variability because its absorption is bile-dependent and affected by concomitant intake of food. Neoral is a microemulsion preconcentrate; a microemulsion is a mixture of the lipophilic active substance with accurately balanced amounts of lipophilic solvent, hydrophilic solvent and surfactant. As the result of advanced microemulsion technique, Neoral has more consistent and improved absorption characteristics. Cyclosporin (cyclosporin A) has been used as an immunosuppressive agent. The major pharmacodynamic action of cyclosporin within T cells is calcineurin inhibition. The complex cyclophilin-cyclosporin competitively binds to the Ca(2+)- and calmodulin-dependent phosphatase calcineurin which then inhibits downstream dephosphorylation and activation of NFAT(transcription factor). The greatest calcineurin inhibition is seen 1-2 h after administration of Neoral in parallel to the highest blood concentration. Variability in cyclosporin exposure was also identified as a risk factor for acute rejection in organ transplant recipients. "Absorption profiling" provides a more accurate prediction of drug exposure and leads to less acute rejection and toxicity. The evolution of Neoral monitoring strategies from trough level to absorption profile will raise the standard of performance of Neoral, resulting in clinical benefits for transplant patients.

Combined treatment with specific ligands for PPARgamma:RXR nuclear receptor system markedly inhibits the expression of cytochrome P450arom in human granulosa cancer cells

Our previous study demonstrated that PPARgamma specific ligand troglitazone (TGZ) or RXR specific ligand LG100268 (LG) alone decreased the aromatase activity in cultured human ovarian granulosa cells from pre-ovulatory follicles, and combined treatment caused an even greater reduction in this activity. Since similar manners of effects of TGZ or/and LG on the aromatase activity in human ovarian granulosa cancer cell line were observed, we performed the detailed analysis of the mechanisms of these effects using this cell line. The changes in the aromatase activity were associated with comparable changes in the P450arom mRNA levels based on a RNase protection assay. A nuclear run-on assay indicated the P450arom transcript to decrease by 40 and 66% at 24 and 48 h, respectively, after TGZ plus LG treatment. An RNA stability analysis showed the half-life of P450arom mRNA to decrease from 13 to 9 h after the TGZ plus LG treatment. The inhibitory effect of TGZ plus LG on the aromatase activity and P450arom mRNA may not be mediated by the cAMP-PKA pathway that is usually implicated in the regulation of aromatase activity in granulosa cells: because (1) the aromatase activity stimulated by forskolin was not inhibited by TGZ plus LG; (2) the specific PKA inhibitor H89 could not block the inhibitory effect of TGZ plus LG on the aromatase activity; and (3) the luciferase activity of P450arom promoter II did not decrease by the addition of TGZ and LG in transfected cells either at a basic state or in the states stimulated by forskolin or PGE2, respectively. Taken together, these results indicate that TGZ plus LG inhibited the aromatase activity and also decreased the P450arom mRNA level in granulosa cancer cells, and the loss of P450arom mRNA expression was considered to be due to both the decreased transcription and rapid degradation of its RNA.

Novel compound heterozygous mutations for lipoprotein lipase deficiency. A G-to-T transversion at the first position of exon 5 causing G154V missense mutation and a 5' splice site mutation of intron 8

We systematically investigated the molecular defects causing a primary LPL deficiency in a Japanese male infant (patient DI) with fasting hyperchylomicronemia (type I hyperlipoproteinemia) and in his parents. Patient DI had neither LPL activity nor immunoreactive LPL mass in the pre- and post-heparin plasma. The patient was a compound heterozygote for novel mutations consisting of a G-to-T transversion at the first nucleotide of exon 5 [+1 position of 3' acceptor splice site (3'-ass) of intron 4] and a T-to-C transition in the invariant GT at position +2 of the 5' donor splice site (5'-dss) of intron 8 (Int8/5'-dss/t(+2)c). The G-to-T transversion, although affecting the 11 nucleotide of the 3'-consensus acceptor splice site, resulted in a substitution of Gly(154) to Val (G154V; GG(716)C(-->)GTC). The mutant G154V LPL expressed in COS-1 cells was catalytically inactive and hardly released from the cells by heparin. The Int8/5'-dss/t(+2)c mutation inactivated the authentic 5' splice site of intron 8 and led to the utilization of a cryptic 5'-dss in exon 8 as an alternative splice site 133 basepairs upstream from the authentic splice site, thereby causing joining of a part of exon 8 to exon 9 with skipping of a 134-bp fragment of exon 8 and intron 8. These additional mutations in the consensus sequences of the 3' and 5' splice sites might be useful for better understanding the factors that are involved in splice site selection in vivo.

In vitro abzyme evolution to optimize antibody recognition for catalysis

Enzymes have evolved their ability to use binding energies for catalysis by increasing the affinity for the transition state of a reaction and decreasing the affinity for the ground state. To evolve abzymes toward higher catalytic activity, we have reconstructed an enzyme-evolutionary process in vitro. Thus, a phage-displayed combinatorial library from a hydrolytic abzyme, 6D9, generated by the conventional in vivo method with immunization of the transition-state analog (TSA), was screened against a newly devised TSA to optimize the differential affinity for the transition state relative to the ground state. The library format successfully afforded evolved variants with 6- to 20-fold increases in activity (kcat) as compared with 6D9. Structural analysis revealed an advantage of the in vitro evolution over the in vivo evolution: an induced catalytic residue in the evolved abzyme arises from double mutations in one codon, which rarely occur in somatic hypermutation in the immune response.

Development of growth hormone and adrenocorticotropic hormone deficiencies in patients with prenatal or perinatal-onset hypothalamic hypopituitarism having invisible or thin pituitary stalk on magnetic resonance imaging

A gradual loss of anterior pituitary hormones is suspected in patients treated with irradiation due to brain tumors. Development of growth hormone deficiency (GHD) with age has been documented in patients with idiopathic GHD. A gradual loss of adrenocorticotropic hormone (ACTH) secretion has been also shown in a patient with severe GHD and an invisible pituitary stalk on magnetic resonance imaging (MRI). The purpose of this longitudinal and cross-sectional study was to evaluate the gradual loss of growth hormone (GH) and ACTH in a homogeneous group of patients with hypopituitarism. Twenty-eight patients (23 males, 5 females) from four hospitals were diagnosed as having prenatal or perinatal-onset hypothalamic hypopituitarism. They had an abnormal pituitary stalk on MRI (invisible in 18 patients, thin in 10 patients) without any other organic disease of the brain. Each patient had GHD upon initial evaluation. Height (n=20) was analyzed as standard deviation score (SDS). Longitudinal (n=8) and cross-sectional (n=28) GH secretion capacity was evaluated by GH peaks, in response to insulin tolerance test (ITT) and growth hormone releasing factor test (GRF test). Longitudinal (n=10) and cross-sectional (n=28) ACTH secretion capacity was evaluated by cortisol peaks in response to ITT. Height SDS decreased each year in all the untreated patients after birth. GH peaks decreased gradually with age. Longitudinal data showed decreased GH peaks with age in seven out of eight patients using ITT and in all four patients using GRF tests. Cortisol peaks also decreased gradually together with signs and symptoms for adrenal deficiency such as general fatigue. Cortisol peaks of less than 414 nmol/L (15 microg/dl) in response to ITT were seen in 24% of the tests before age 10 and 56% before age 25. In conclusion, GHD and ACTH deficiency developed gradually in patients with prenatal or perinatal-onset hypothalamic hypopituitarism who had invisible or thin pituitary stalks examined by MRI.

[Hypersensitivity pneumonitis caused by a factory humidifier. A case report]

A 64-year-old man was hospitalized for productive cough and dyspnea. Both chest radiographs and CT scans showed areas of ground-glass opacity in the middle and lower lung fields on both sides. The BAL and TBLB findings were compatible with hypersensitivity pneumonitis. The serum was negative for antibodies against Trichosporon species, and the result of a lymphocyte stimulating test for administered drugs including a Chinese medicine was also negative. A humidifier was suspected as the cause because it had been used for more than 10 years in the factory where the patient had been working. An inhalation test using the humidifier fluid successfully provoked dyspnea, fever and fine crackle, and laboratory tests demonstrated hypoxemia, reduction in vital capacity and the elevation of CRP. Agar gel diffusion using the patient's serum showed a precipitating line against Cephalosporium acremonium, but this line did not fuse with any precipitating line formed between the humidifier fluid and the serum, indicating that no Cephalosporium was Present in the humidifier fluid. Since a high level of beta-D glucan was detected in the humidifier fluid, an unidentified fungus was suspected to be the antigen.

Characterization of the stromal protease(s) degrading the cross-linked products of the D1 protein generated by photoinhibition of photosystem II

When photosystem (PS) II-enriched membranes are exposed to strong light, cross-linking of the intrinsic D1 protein with the surrounding polypeptides and degradation of the D1 protein take place. The cross-linking of the D1 protein with the alpha-subunit of cytochrome b(559) is suggested to be an early event of photoinduced damage to the D1 protein (Barbato et al., FEBS Lett. 309 (1992) 165-169). The relationship between the cross-linking and the degradation of the D1 protein, however, is not yet clear. In the present study, we show that the addition of stromal extract from chloroplasts degrades the 41 kDa cross-linked product of D1/cytochrome b(559) alpha-subunit and enhances the degradation of the D1 protein. Incubation of the preilluminated PS II-enriched membranes with the stromal extract at 25 degrees C causes the degradation of the cross-linked product by more than 70%. The activity of the stromal extract showed a pH optimum at 8.0, and was enhanced by the addition of ATP or GTP. Consistent with the nucleotide effect, this stromal activity was eliminated by the preincubation of the stromal extract with apyrase, which hydrolyzes nucleotides. Also, the stromal activity was nearly fully inhibited by a serine-type protease inhibitor, 3,4-dichloroisocoumarin, which suggests participation of a serine-type protease(s).

Establishment and characterization of a steroidogenic human granulosa-like tumor cell line, KGN, that expresses functional follicle-stimulating hormone receptor

We established a steroidogenic human ovarian granulosa-like tumor cell line, designated KGN, from a patient with invasive ovarian granulosa cell carcinoma. KGN had a relatively long population doubling time of about 46.4 h and had an abnormal karyotype of 45,XX, 7q-, -22. A steroid analysis of the cultured medium by RIA performed 5 yr after the initiation of culture showed that KGN was able to secrete pregnenolone and progesterone, and both dramatically increased after stimulation with (Bu)(2)cAMP. However, little or no secretion of 17alpha-hydroxylated steroids, dehydroepiandrosterone, androstenedione, or estradiol was observed. The aromatase activity of KGN was relatively high and was further stimulated by (Bu)(2)cAMP or FSH. These findings showed a pattern similar to that of steroidogenesis in human granulosa cells, thus allowing analysis of naturally occurring steroidogenesis in human granulosa cells. Fas-mediated apoptosis of KGN was also observed, which mimicked the physiological regulation of apoptosis in normal human granulosa cells. Based on these findings, this cell line is considered to be a very useful model for understanding the regulation of steroidogenesis, cell growth, and apoptosis in human granulosa cells.

Selective stimulation of G-CSF gene expression in macrophages by a stimulatory monoclonal antibody as detected by a luciferase reporter gene assay

We have identified a stimulatory monoclonal antibody (mAb) from autoimmune mice that selectively stimulates granulocyte colony-stimulating factor (G-CSF) gene expression in a mouse macrophage cell line. The induction was observed not only in the cell line, but also in normal peritoneal macrophages. This mAb bound to the monocyte/macrophage cell lines and pre-B leukemia cell lines, but also in normal peritoneal macrophages, whereas it did not bind to normal T and B cells in the spleen or fibroblastic cell lines. It could even bind to a human promyelocytic leukemia cell line, when they were differentiated into monocytic cells. On Western blotting, this mAb mainly recognized an approximately 30-kDa band and it was unique because there have been no reports of membrane-associated proteins with a similar molecular mass found in macrophages. These results suggest that there could be a specific gateway molecule to induce G-CSF in macrophages.

A nuclear receptor system constituted by RAR and RXR induces aromatase activity in MCF-7 human breast cancer cells

Estrogen is the most important endocrine hormone that stimulates the growth of hormone-dependent breast cancer. The biosynthesis of estrogens in breast tissue is catalyzed by cytochrome P450 aromatase (P450arom). The expression of P450arom is controlled by the tissue- or cell-specific promoters of CYP 19 gene. The roles of nuclear receptor systems for the aromatase activity in breast cancer cells have not yet been fully investigated. In the present study, we investigated the effects of a nuclear receptor system constituted by retinoid X receptor (RXR) and its heterodimer partner on the aromatase activity in a cultured MCF-7 human breast cancer cell line, using each selective ligand for retinoic acid receptor (RAR) (TTNPB), RXR (LG100268), PPARgamma (troglitazone), and vitamin D(3) receptor (vitamin D(3)). The treatment of the cells with TTNPB or LG100268 alone for 2 days increased slightly the aromatase activity, but the increases were not statistically significant in comparison to the control. However, the combined treatment with TTNPB (10(-7) M) and LG100268 (10(-7) M) caused a dramatic stimulation of the aromatase activity. The treatment with other ligands had little or no effect on the aromatase activity. The stimulation of the aromatase activity by TTNPB plus LG100268 was dose-dependent, and a maximum stimulation was observed at 10(-7) M in both compounds. In addition, the increase in the aromatase activity was accompanied by an increase in the P450arom mRNA levels determined by RT-PCR in MCF-7 cells. The increase in the P450arom transcript was also found to be related to the specific usage of promoter 1a of the CYP 19 gene based on the analysis using RT-PCR. This is the first demonstration that a nuclear receptor system constituted by a RAR:RXR heterodimer is involved in the regulation of aromatase activity in MCF-7 breast cancer cells.

Distribution of capsaicin-sensitive substance P- and calcitonin gene-related peptide-immunoreactive nerves in bovine respiratory tract

The distribution of nerve fibers immunoreactive for substance P (SP) and calcitonin gene-related peptide (CGRP) was examined by means of immunohistochemical methods in the respiratory tract from nose to lung of normal and capsaicin-treated cattle. SP- and CGRP-immunoreactive (IR) nerve fibers with varicosities were detected in all portions. They were more numerous in calves than in cows. They were abundant in the nasal and laryngeal mucosae and tracheal bronchus, and few in number in the lung. SP- and CGRP-IR nerve fibers were mainly seen in the epithelium, in connective tissue beneath the epithelium and around blood vessels, and in the glands throughout the respiratory tract. In contrast, SP- and CGRP-IR nerve fibers were sparse in the smooth muscle layer. Capsaicin treatment of neonates caused a remarkable reduction in the number of SP- and CGRP-IR nerve fibers in the respiratory tract of calves. Double immunofluorescence experiments showed the colocalization of SP and CGRP in most of the nerve fibers. The present findings suggest that SP- and CGRP-IR nerve fibers are involved in the regulation of the bovine respiratory tract, and that capsaicin-sensitive SP- and CGRP-IR nerve fibers are sensory neurons of the bovine respiratory tract.

A Drosophila Winged-helix nude (Whn)-like transcription factor with essential functions throughout development

A Drosophila gene, Dwhn (Drosophila whn-like), encoding a putative transcriptional regulator with a DNA binding domain similar to that of mouse Winged-helix nude (Whn) was cloned. Analyses of the phenotypes produced by a hypomorphic mutation and transgene expression suggested a role in cell fate decision during the differentiation of the compound eye, wing veins and bristles. During embryonic development, Dwhn expression started ubiquitously followed by more restricted expression in striking contrast to the expression patterns of other Drosophila forkhead (fkh) family genes whose local expression correlate well to their roles as local homeotic genes. This broad expression may correspond to the multiple defects in embryos homozygous for strong alleles, such as defects in the formation of central and peripheral nervous systems, germ band retraction, head involution, and dorsal closure. The DNA binding specificity of Dwhn differed from that of Whn despite the strong sequence conservation in the DNA binding domain. Dwhn is the first invertebrate Whn-like transcriptional regulator, and should provide insights into the basic functions and evolution of the whn family genes.

Insulin sensitizer, troglitazone, directly inhibits aromatase activity in human ovarian granulosa cells

Ovarian granulosa cells synthesize estrogens from androgens, which are catalyzed by aromatase cytochrome P450 (P450arom). Troglitazone (Tro), one of the insulin-sensitizing compounds, thiazolidinediones (TZDs), is a ligand for peroxisome proliferator activated receptor gamma (PPARgamma) and is effective in the treatment of both non-insulin-dependent diabetes mellitus (NIDDM) as well as polycystic ovary syndrome (PCOS). PPARgamma exerts a transcriptional activity as a PPARgamma:RXR heterodimer. In this study, we investigated the effects of Tro and/or RXR ligand, LG100268 (LG) on the aromatase activity in cultured human ovarian granulosa cells obtained from patients who underwent in vitro fertilization. Human ovarian granulosa cells expressed PPARgamma mRNA assessed by RT-PCR. The treatment of the granulosa cells with Tro for 24 h resulted in a dramatic inhibition of the aromatase activity in a dose-dependent manner. While the treatment with LG alone also inhibited the aromatase activity, the combined treatment with both Tro and LG caused a much more reduction in the aromatase activity. The changes in the aromatase activity by Tro and/or LG were associated with comparable changes in P450arom mRNA assessed by RT-PCR. These results suggest that Tro directly inhibit the aromatase activity in human granulosa cells probably via nuclear receptor system PPARgamma:RXR heterodimer. The findings may provide a biochemical basis for the decrease in the blood concentrations of estrogens which is observed after the in vivo administration of Tro and may also possibly be useful as a novel therapy for estrogen-dependent diseases.

Impression pressures against teeth in a partially edentulous model with a mobile tooth: influence of impression tray design

The purpose of the present study was to examine the effect of custom tray designs on local pressures against teeth during the impression procedure. In a previous study, a partially edentulous simulation model with a mobile tooth was used, and the effect of custom tray designs on the displacement of the mobile tooth was examined during the impression procedure. Based on that study's results, we have assumed that the differences in impression pressures between the labial and the lingual sides of a mobile tooth could either cause or affect displacement. The present study was undertaken to determine the local impression pressures against each side of three anterior teeth, including one mobile tooth, using the same simulation model and the same custom trays as in the previous study. It was found that the local pressures exerted against teeth during the impression procedure were affected by the custom tray designs and varied according to the coronal shape, axis inclination and location of the teeth.

Prevalence of GH-1 gene deletion in patients with isolated growth hormone deficiency in Japan. GH Gene Study Group

A multicenter study was carried out to investigate the prevalence of growth hormone (GH-1) gene deletions among patients with isolated growth hormone deficiency (IGHD) and extremely short stature in Japan, using PCR method. Genomic DNA was extracted from the whole blood samples of 48 patients (34 males and 14 females) at 20 hospitals. All the patients fulfilled the inclusion criteria as follows: (1) IGHD patients whose every peak serum GH level in more than two tests <5 ng/ml and (2) pretreatment height < -- 3SD, regardless of family history and facial feature characteristic of GH-1 gene deletion. The subjects were screened for deletions in GH-1 gene, using a PCR method that could identify deletions of 6.7, 7.0 and 7.6 kbp. Three (6.25%) out of 48 subjects were found to have such deletion fragments. The first case was a boy homozygous for deletion of 6.7 kbp fragments. The second case was a girl heterozygous for 6.7 kbp deletion. A direct sequence analysis revealed a 2-bp deletion in exon 3 on the remaining allele that created a stop codon in exon 4. The third case was a boy also heterozygous for 6.7 kbp deletion. By direct sequencing analysis, three point mutations were detected in the promoter region on the opposite allele together with a four-base addition at base 250. One of the mutations was in the area of Pit-1 binding site (at base - 123). The latter two cases apparently represent new types of compound heterozygote of GH-1 gene deletion. Our results suggest that GH-1 gene mutation is not so rare in extremely short IGHD children in Japan.

Identification of novel human GH-1 gene polymorphisms that are associated with growth hormone secretion and height

Height, which is partially determined by GH secretion, is genetically influenced. The purpose of this study was to identify polymorphisms in the GH-1 gene, which are associated with altered GH production. The subjects included prepubertal short children with GH insufficiency without gross pituitary abnormalities (n = 43), short children with normal GH secretion (n = 46), and normal adults (n = 294). A polymorphism in intron 4 (P-1, A or T at base 1663) was identified. Two additional polymorphic sites (P-2, T or G at base 218, and P-3, G or T at base 439) in the promoter region of the GH-1 gene were also identified and matched with the P-1 polymorphism (A or T, respectively) in more than 90% of the subjects. P-1, P-2, and P-3 were considered to be associated with GH production, and the results of P-2 are explained as a representative in this abstract. For example, the allele frequency of T at P-2 in prepubertal short children with GH insufficiency without gross pituitary abnormalities (58.1%) was significantly different from that in short children with normal GH secretion and normal adults (37.0% and 43.5%, respectively; P < 0.001). Furthermore, significant differences were observed in maximal GH peaks in provocative tests (11.1 vs. 18.2 ng/mL, P = 0.006), insulin-like growth factor I SD scores (SDS) (-2.4 vs. -0.8, P < 0.0001), and height (Ht) SDS (-3.7 vs. -3.0, P = 0/001) in children with the T/T or G/G genotypes at P-2, respectively. In the entire study group, significant differences in insulin-like growth factor SDS (T/T, -0.9; G/G, -0.2; P = 0.0009) and Ht SDS (T/T, -1.0; G/G, -0.4; P = 0.022) were observed between the T/T and G/G genotypes at P-2. These data indicate that GH secretion is partially determined by polymorphisms in the GH-1 gene, which explain some of the variations in GH secretion and Ht.

Identification of a novel 70 kDa protein that binds to the core promoter element and is essential for ribosomal DNA transcription

Mammalian ribosomal RNA genes (rDNA) are transcribed by RNA polymerase I and at least two auxiliary factors, UBF and SL1/TFID/TIF-IB. It has also been reported that an additional factor(s) is required to reconstitute efficient initiation of rDNA transcription in vitro, depending upon the procedures of chromatographic separation. In an attempt to elucidate the molecular identity of such yet uncertain activities, we have developed agarose gel shift and UV cross-linking assays to detect proteins directly bound to the core promoter region of murine rDNA. With these techniques, we identified a 70 kDa protein (p70) in the flow-through fraction of a phosphocellulose column (TFIA-fraction). Interestingly, the binding of p70 to the rDNA core promoter was observed only in the presence of the SL1-containing fraction. The probable human orthologue of p70 was also detected in HeLa cells. Consistent with the observation that p70 bound to the core promoter only in the presence of the TFIA- and SL1-fractions, alteration of DNase I footprint pattern over the core promoter element was demonstrated by cooperative action of the TFIA- and SL1-fractions. A reconstituted in vitro transcription assay with further purified p70 indicated that p70 was required for accurate initiation of rDNA transcription. These results indicate that the p70 identified recently by the current DNA-binding experiments represents a novel transcription factor in rDNA transcription.

Improved generation of catalytic antibodies by MRL/MPJ-lpr/lpr autoimmune mice

To compare the abilities of different strains of mice to elicit catalytic antibodies (Abs), we determined the occurrence of esterolytic Abs in BALB/c (normal strain) and MRL/MPJ-lpr/lpr (MRL/lpr, autoimmune) mice after immunization with the transition state analog (TSA) 1. Hybridoma supernatants elicited against TSA 1 were screened by ELISA for binding to the BSA-conjugated TSA 1 (=3b), and then screened for binding to the BSA-linked short TSA 2 (=4). We obtained eight times more positives from MRL/lpr mice than from BALB/c mice by these screening steps. The monoclonal antibodies (mAbs) obtained here were examined for binding and catalytic activity. Fifteen of 25 mAbs from MRL/lpr had esterolytic activity, compared with only two of 21 mAbs from BALB/c. These results demonstrated that the occurrence of catalytic Abs was much higher in MRL/lpr mice than in BALB/c mice, which is in good agreement with the previous report by Tawfik et al. [Tawfik, D.S., Chap, R., Green, B.S., Sela, M., Eshhar, Z., 1995. Proc. Natl. Acad. Sci. U.S.A. 92, 2145-2149] using a different kind of TSA. Thus, these studies strongly suggest that using the appropriate strain can be a key factor in the efficient production of catalytic Abs. Furthermore, these mAbs were characterized to elucidate the mechanism of strain difference, and determine whether MRL/lpr mice can be used with other TSAs for the efficient production of catalytic Abs.