Changes in the expression of α-tocopherol-related genes in liver and mammary gland biopsy specimens of peripartum dairy cows.

Blood α-tocopherol (α-Toc) concentrations decline gradually throughout the prepartum period, reaching the nadir after calving in dairy cows. The 6 α-Toc-related molecules [α-Toc transfer protein (TTPA); afamin; scavenger receptor class B, Type I; ATP-binding cassette transporter A1; tocopherol-associated protein (SEC14L2); and cytochrome P450 family 4, subfamily F, polypeptide 2 (CYP4F2)] are expressed in liver and other peripheral tissues. These molecules could regulate α-Toc transport, blood concentrations, and metabolism of α-Toc. Therefore, the aim of this study was to evaluate the changes in the expression of α-Toc-related genes in liver and mammary gland tissues of dairy cows around calving, which have remained elusive until now. In experiment (Exp.) 1, 28 multiparous Holstein cows were used (from -5 to 6 wk relative to parturition) to monitor the changes in dietary α-Toc intake, blood concentrations of α-Toc, and lipoproteins; in Exp. 2, 7 peripartum Holstein cows were used (from -4 to 4 wk relative to parturition) for liver tissue biopsy; and in Exp. 3, 10 peripartum Holstein cows were used (from -8 to 6 wk relative to parturition) to carry out the mammary gland tissue biopsy and milk sampling. In Exp. 1, the serum α-Toc concentrations declined gradually with decreasing amount of α-Toc intake and plasma high-density lipoprotein concentrations toward calving time. However, in the early lactation period after calving, serum α-Toc concentrations remained at a lower concentration despite the recovery of α-Toc intake and plasma high-density lipoprotein concentrations. In Exp. 2, just after calving, the TTPA, SEC14L2, afamin, and albumin mRNA expression levels in the liver were temporarily downregulated, and the hepatic mRNA levels of endoplasmic reticulum stress-induced unfolded protein response markers and acute-phase response marker increased at calving. In Exp. 3, the concentrations of α-Toc in colostrum were greater than those in precolostrum (samples were collected at wk -1 relative to parturition) and mature milk. The expression of TTPA, SEC14L2, and CYP4F2 mRNA in bovine mammary gland tissue was detected. However, TTPA and SEC14L2 mRNA expressions showed the opposite trends: the expression levels of TTPA mRNA peaked whereas SEC14L2 mRNA reached a nadir at calving. These results indicate that the expression of α-Toc-related genes involved in specific α-Toc transfer and metabolism in the liver and mammary gland are altered during calving. Moreover, these changes might be associated with the maintenance of lower serum α-Toc concentrations after calving.

Expression of α-tocopherol-associated genes and α-tocopherol accumulation in Japanese Black (Wagyu) calves with and without α-tocopherol supplementation.

The aim of the study was to clarify 1) the distribution of 6 α-tocopherol (α-Toc)-associated gene expressions in 20 major tissues, including metabolic, reproductive, endocrine, immune, and digestive and absorptive tissues, in relation to α-Toc status and 2) the change in expression patterns of the genes induced when α-Toc was orally administered to Japanese Black (JB) calves. This study examined weaned male JB calves ( = 10), of which 5 calves were orally administered α-Toc for 2 wk (30 IU·kg BW·d; TOC group). The others did not receive the α-Toc supplement and were the control (CONT) group. The 20 tissues and venous blood (serum) were sampled on the final day. In both groups, the mean mRNA expression levels for α-Toc transfer protein, afamin (AFM), ATP-binding cassette transporter A1, and tocopherol-associated protein were greatest in the liver ( < 0.05), whereas scavenger receptor class B, Type I (SR-BI) mRNA was greatest in the adrenal gland ( < 0.05). The gene for cytochrome P450 family 4, subfamily F, polypeptide 2 was most highly expressed in the liver, testes, and adrenal gland. The α-Toc content was greatest ( < 0.05) in the testes of the 20 sampled tissues in the CONT group. However, the levels in the testes and jejunum were similar and greater ( < 0.05) than the levels in the other 18 tissues in the TOC group. The mean increase in α-Toc levels after oral α-Toc administration (mean α-Toc content for the TOC group divided by the CONT group content) were greater ( < 0.05) in the jejunum (40.7-fold) and duodenum and liver (26.3- and 23.1-fold) than in the serum (7.8-fold). In the liver, α-Toc administration significantly increased ( < 0.05) the AFM and SR-BI mRNA expression levels. The results show that the liver may play an important role in the regulation of α-Toc disposition, but other peripheral tissues that accumulate large amounts of α-Toc could moderate the local α-Toc status and functions, as inferred from the high expressions of the α-Toc-associated genes in JB calves.

Hypothalamic ATF3 is involved in regulating glucose and energy metabolism in mice.

AIMS/HYPOTHESIS: The pancreas and hypothalamus are critical for maintaining nutrient and energy homeostasis, and combined disorders in these organs account for the onset of the metabolic syndrome. Activating transcription factor 3 (ATF3) is an adaptive response transcription factor. The physiological role of ATF3 in the pancreas has been controversial, and its role in the hypothalamus remains unknown. To elucidate the roles of ATF3 in these organs, we generated pancreas- and hypothalamus-specific Atf3 knockout (PHT-Atf3-KO) mice in this study. METHODS: We crossed mice bearing floxed Atf3 alleles with Pdx1-cre mice, in which cre is specifically expressed in the pancreas and hypothalamus, and analysed metabolic variables, pancreatic morphology, food intake, energy expenditure and sympathetic activity in adipose tissue. We also used a hypothalamic cell line to investigate the molecular mechanism by which ATF3 regulates transcription of the gene encoding agouti-related protein (Agrp). RESULTS: Although PHT-Atf3-KO mice displayed better glucose tolerance, neither plasma glucagon nor insulin level was altered in these mice. However, these mice exhibited higher insulin sensitivity, which was accompanied by a leaner phenotype due to decreased food intake and increased energy expenditure. We also observed decreased hypothalamic Agrp expression in PHT-Atf3-KO mice. Importantly, an increase in ATF3 levels is induced by fasting or low glucose in the hypothalamus. We also showed that ATF3 interacts with forkhead box-containing protein, O subfamily 1 (FoxO1) on the Agrp promoter and activates Agrp transcription. CONCLUSIONS/INTERPRETATION: Our results suggest that ATF3 plays an important role in the control of glucose and energy metabolism by regulating Agrp.

Key role of ATF3 in p53-dependent DR5 induction upon DNA damage of human colon cancer cells.

Stress response gene ATF3 is one of the p53 target genes and has a tumor suppressor role in cancer. However, the biological role of p53-ATF3 pathway is not well understood. Death receptor 5 (DR5) is a death domain-containing transmembrane receptor that triggers cell death upon binding to its ligand TRAIL (tumor necrosis factor-related apoptosis-inducing ligand), and a combination of TRAIL and agents that increase the expression of DR5 is expected as a novel anticancer therapy. In this report, we demonstrate that ATF3 is required for efficient DR5 induction upon DNA damage by camptothecin (CPT) in colorectal cancer cells. In the absence of ATF3, induction of DR5 messenger RNA and protein is remarkably abrogated, and this is associated with reduced cell death by TRAIL and CPT. By contrast, exogenous expression of ATF3 causes more rapid and elevated expression of DR5, resulting in enhanced sensitivity to apoptotic cell death by TRAIL/CPT. Reporter assay and DNA affinity precipitation assay demonstrate that at least three ATF/CRE motifs at the proximal promoter of the human DR5 gene are involved in the activation of DNA damage-induced DR5 gene transcription. Furthermore, ATF3 is shown to interact with p53 to form a complex on the DR5 gene by Re-chromatin immunoprecipitation assay. Taken together, our results provide a novel insight into the role of ATF3 as an essential co-transcription factor for p53 upon DNA damage, and this may represent a useful biomarker for TRAIL-based anticancer therapy.

Role of Necl-5 in the pathophysiology of colorectal lesions induced by dimethylhydrazine and/or dextran sodium sulphate.

Necl-5 is an immunoglobulin-like molecule that was originally identified as a poliovirus receptor. Although Necl-5 expression is often up-regulated in cancer cells, its pathophysiological significance in the development of cancer remains unclear. We investigated the roles of Necl-5 in the development of colitis-associated neoplasia. Necl-5-deficient mice were generated and treated with dimethylhydrazine (DMH) and/or dextran sodium sulphate (DSS) to induce colitis and its associated neoplasias. Colon tissues were examined for histology, Ki-67 expression by immunohistochemistry and K-ras gene mutation. Colon tumours occurred significantly less frequently in heterozygous (Necl-5(+/-)) or homozygous Necl-5-deficient (Necl-5(-/-)) mice than in wild-type (WT) mice with DMH/DSS treatment. Total ulcer index and inflammatory cell infiltration were significantly lower in Necl-5(-/-) mice than in WT mice with DSS alone or DMH/DSS treatment. Colon tumours in both WT and Necl-5(-/-) mice showed high cell proliferation ability but lacked K-ras mutation. The total Ki-67 labelling index in non-neoplastic colon epithelium was significantly higher in WT (45.9 +/- 0.94) than in Necl-5(+/-) (34.3 +/- 1.40) or Necl-5(-/-) (27.7 +/- 1.15) mice with DMH/DSS treatment (p < 0.001). Necl-5 plays a role in the development of colitis-associated cancer by up-regulating colonic mucosal cell proliferation.

Can low frequency sound stimulation during posturography help diagnosing possible perilymphatic fistula in patients with sensorineural hearing loss and/or vertigo?

Perilymphatic fistula (PLF) is often difficult to diagnose because of the similar symptomatology, such as vertigo, tinnitus and hearing loss, which is found in several inner ear diseases. We attempted to correlate a positive result of low frequency sound (LFS) stimulation tests in posturography with the presence or absence of a PLF confirmed by transtympanic endoscopy in 209 patients with various inner ear diseases (Meniere's disease ( n=128), vestibulopathy ( n=41), cochleopathy ( n=28) and sudden deafness ( n=12). LFS provoked unsteadiness in posturography without PLF in 24 patients with Meniere's disease, in 5 patients with vestibulopathy, in 3 patients with cochleopathy and in 2 patients with sudden deafness. In one patient, tympanoscopy revealed fistula in the round window membrane that was covered with a fibrinous layer. In four cases there was abnormal light reflex in the round window but without PLF. In eight cases, Hennebert's sign was present with nystagmus, without PLF. We conclude that pathological responses to the LFS test in posturography can also be encountered in other inner ear diseases without PLF.

Basic fibroblast growth factor in nasal polyps immunohistochemical and quantitative findings.

Basic fibroblast growth factor (bFGF) is a mediator with potent mitogenic properties. Increased amounts of this mediator have been demonstrated in damaged lung tissue, and it has been suggested to increase the healing of gastro-duodenal ulcers. In order to quantify the amounts and document the localization of bFGF in nasal polyps, polyp tissue from 12 patients undergoing polypectomy was analyzed by ELISA and immunohistochemistry. Mucosa from the inferior turbinate was analyzed in the same manner for comparison. The amount of bFGF detected in polyp tissue was significantly higher than that in turbinate mucosa. The amount of bFGF was also significantly higher in the group of patients with high degree of inflammation. The immunohistochemical findings demonstrated abundant bFGF activity mainly in the glandular acini, in the epithelium, in infiltrating inflammatory cells and in the vessel walls. We propose that bFGF may contribute in a significant way to the formation of nasal polyps.

Silicone granuloma on the entry points of acupuncture, venepuncture and surgical needles.

We describe a case of epithelioid granuloma on the entry points of needles used for acupuncture, venepuncture and for taking skin biopsy. The acupuncture needles used at each session were silicone coated. Silicon was detected in the vacuoles of macrophages and multiple nucleated giant cells by X-ray microanalysis. To our knowledge, this is the first case of silicone granuloma arising on the entry points of acupuncture, venepuncture and surgical needles.

Laser-assisted myringoplasty--technical aspects.

At lower power, lasers fuse collagen fibres and weld tissues. Welded collagen fibres make a solid bond and allow tissue growth along the bonded edges. Our aim was to study applicability of lasers in myringoplasty. We used a KTP-532 laser in outpatient myringoplasty. The laser beam was delivered through a micromanipulator connected to a microscope or through a 200-400-micron silica fibre. The perichondrium was used for transplantant and harvested from the tragus. The margins of the perforation in the eardrum were evaporated, with the laser operating in a continuous mode at 2-4 W. The middle ear was filled with gelfilm to provide support for the transplant. The perichondrium was placed under the margins of the tympanic membrane and lazed at low power (0.2-1.5 W) in continuous mode. In pale tissues, venous blood, methylene blue or fluorescein was used to enhance the tissue admittance of laser energy. Surgical failures were linked to thermal tissue damage due to excessive energy during lazing. In two cases, visibility via microscope into the anterior edge was not complete and the transplantant did not adhere in the relatively limited area. One patient had epidermal growth under the tympanic membrane and developed local cholesteatoma. Laser-assisted myringoplasty provides several advantages over traditional myringoplasty: it is minimally invasive, no manipulation of the ossicles is needed and it is convenient in anterior perforations, where it can be done endoscopically. We prefer a fibre delivery system to a micromanipulator, as lazing with endoscopes is possible and thermal damage is easier to prevent.

Involvement of a small GTP-binding protein (G protein) regulator, small G protein GDP dissociation stimulator, in antiapoptotic cell survival signaling.

Small GTP-binding protein GDP dissociation stimulator (Smg GDS) regulates GDP/GTP exchange reaction of Ki-Ras and the Rho and Rap1 family members and inhibits their binding to membranes. In fibroblasts, Smg GDS shows mitogenic and transforming activities in cooperation with Ki-Ras. However, the physiological function of Smg GDS remains unknown. Here we show that mice lacking Smg GDS died of heart failure shortly after birth, not resulting from developmental heart defects but from enhanced apoptosis of cardiomyocytes triggered by cardiovascular overload. Furthermore, neonatal thymocytes and developing neuronal cells underwent apoptotic cell death. Smg GDS-/- thymocytes were susceptible to apoptotic inducers, such as etoposide and UV irradiation. Smg GDS-/- thymocytes were protected from etoposide-induced cell death by ex vivo transduction of the Smg GDS cDNA. These phenotypes partly coincide with those observed in Ki-Ras-deficient mice, suggesting that Smg GDS is involved in antiapoptotic cell survival signaling through Ki-Ras.

[Phaeomycotic cyst caused by Phaeoacremonium parasiticum].

Phaeoacremonium parasiticum was identified as the causative agent of a phaeomycotic cyst seen just below the right knee of a 59-year-old healthy woman. She had no history of trauma. Direct KOH examination of the pus aspirated from the subcutaneous nodule revealed abundant mycelia, which were not too deeply brown in color. The nodule was surgically excised, and there was no recurrence during a half year of observation. Tissue section of the excised material revealed rather a large cavity extending from the cutis to the subcutis. The cavity had a thick wall composed of granulomatous tissues. Mycelial and yeast-like fungal elements were seen within the cavity and the granulomatous tissues. A dematiaceous fungus was cultured from both pus and the excised material. The isolates were characterized by a dark green to black colony, unbranched or infrequently branched, brownish conidiophores bearing an aculeate monophialide with a narrow funnel-shaped collarette, and slimy, hyaline, one-celled, ellipsoid to allantoid conidia.

Practical protective tools for occupational exposure: 1) double focus spectacles for the aged with highly refracted glass lens 2) remodeled barrier for radiation protection.

SUMMARY: Two practical protective tools for occupational exposure for neurointerventional radiologists are presented. The first purpose of this study was to investigate the effectiveness of double focus spectacles for the aged with a highly refracted glass lens (special spectacles for the aged) for radiation protection of the crystalline lens of the eye in comparison with other spectacles on the market, based on the measurement of film density which was obtained by exposure of X-ray through those spectacles. As a result of the film densitometry mentioned above, the effectiveness of special spectacles for the aged in radiation protection was nearly equal to the effectiveness of a goggle type shield which is made with a 0.07 mm lead-equivalent plastic lens. The second purpose of this study was to investigate the effectiveness of the protective barrier, which we remodeled for cerebral angiography or neuroendovascular therapy, for radiation exposure, based on the measurement in a simulated study with a head phantom, and on the measurement of radiation exposure in operaters during procedures of clinical cases. In the experimental study radiation exposure in supposed position of the crystalline lens was reduced to about one third and radiation exposure in supposed position of the gonadal glands was reduced to about one seventh, compared to radiation exposure without employing the barrier. The radiation exposure was monitored at the left breast of three radiologists, in 215 cases of cerebral angiography. Employing the barrier in cerebral angiography, average equivalent dose at the left breast measured 1.49mu Sv during 10 min of fluoroscopy. In three kinds of neuroendovascular therapy in 40 cases, radiation exposure in an operator was monitored in the same fashion and the dose was recorded less than the result reported in previous papers in which any protective barrier have not been employed in the procedure (1,2). As a result, the two above mentioned protective tools are considered practical in clinical usage and very effective to reduce radiation exposure in an operator of interventional neuroradiolgy which may sometimes require many hours to complete the therapy under extended fluoroscopic time. 1) The first topic of this report is double focus spectacles for the aged with a highly refracted glass lens (special spectacles for the aged).

Afadin: A key molecule essential for structural organization of cell-cell junctions of polarized epithelia during embryogenesis.

Afadin is an actin filament-binding protein that binds to nectin, an immunoglobulin-like cell adhesion molecule, and is colocalized with nectin at cadherin-based cell-cell adherens junctions (AJs). To explore the function of afadin in cell-cell adhesion during embryogenesis, we generated afadin(-/-) mice and embryonic stem cells. In wild-type mice at embryonic days 6.5-8.5, afadin was highly expressed in the embryonic ectoderm and the mesoderm, but hardly detected in the extraembryonic regions such as the visceral endoderm. Afadin(-/-) mice showed developmental defects at stages during and after gastrulation, including disorganization of the ectoderm, impaired migration of the mesoderm, and loss of somites and other structures derived from both the ectoderm and the mesoderm. Cystic embryoid bodies derived from afadin(-/-) embryonic stem cells showed normal organization of the endoderm but disorganization of the ectoderm. Cell-cell AJs and tight junctions were improperly organized in the ectoderm of afadin(-/-) mice and embryoid bodies. These results indicate that afadin is highly expressed in the ectoderm- derived cells during embryogenesis and plays a key role in proper organization of AJs and tight junctions of the highly expressing cells, which is essential for proper tissue morphogenesis.

Progressive impairment of kidneys and reproductive organs in mice lacking Rho GDIalpha.

The Rho small G protein family members regulate various actin cytoskeleton-dependent cell functions. The Rho GDI (GDP dissociation inhibitor) family, consisting of Rho GDIalpha, -beta, and -gamma, is a regulator that keeps the Rho family members in the cytosol as the GDP-bound inactive form and translocates the GDP-bound form from the membranes to the cytosol after the GTP-bound form accomplishes their functions. Rho GDIalpha is ubiquitously expressed in mouse tissues and shows GDI activity on all the Rho family members in vitro. We have generated mice lacking Rho GDIalpha by homologous recombination to clarify its in vivo function. Rho GDIalpha -/- mice showed several abnormal phenotypes. Firstly, Rho GDIalpha -/- mice were initially viable but developed massive proteinuria mimicking nephrotic syndrome, leading to death due to renal failure within a year. Histologically, degeneration of tubular epithelial cells and dilatation of distal and collecting tubules were readily detected in the kidneys. Secondly, Rho GDIalpha -/- male mice were infertile and showed impaired spermatogenesis with vacuolar degeneration of seminiferous tubules in their testes. Thirdly, Rho GDIalpha -/- embryos derived from Rho GDIalpha -/- female mice were defective in the postimplantation development. In addition, these morphological and functional abnormalities showed age-dependent progression. These results suggest that the signaling pathways of the Rho family members regulated by Rho GDIalpha play important roles in maintaining the structure and physiological function of at least kidneys and reproductive systems in adult mice.

In vitro metabolism of a new anticancer agent, 6-N-formylamino-12, 13-dihydro-1,11-dihydroxy-13-(beta-D-glucopyranosil)5H-indolo+ ++[2,3-a]pyrrolo[3,4-c]carbazole-5,7(6H)-dione (NB-506), in mice, rats, dogs, and humans.

The metabolism of 6-N-formylamino-12,13-dihydro-1, 11-dihydroxy-13-(beta-D-glucopyranosil)5H-indolo [2,3-a]pyrrolo [3, 4-c]carbazole-5,7(6H)-dione (NB-506), a potent inhibitor of DNA topoisomerase I, was characterized in mice, rats, dogs, and humans in vitro. NB-506 was deformylated to ED-501 in mouse and rat plasma with enzyme activity of 140 and 116 pmol/min/mg protein, respectively. The enzyme activity in dog and human plasma was found to be less than 1.7 pmol/min/mg protein. In liver S9 and small intestine S9 samples from mice and rats, activity of the enzyme was very low. Also, there was no activity in the liver or small intestine of dogs and humans. The enzyme involved in the conversion of NB-506 to ED-501 in rat plasma is a rodent-specific serine enzyme with a molecular mass of 138KDa. The Vmax and Km values were 6.3 nmol/min/ml plasma and 54 microM at an optimum pH of 7.4, respectively. Although NB-506 was converted to ED-551 in dog and human plasma in vitro, no conversion was observed in mouse and rat plasma. In human plasma this conversion was not affected by heat treatment (100 degreesC for 1 min), but was inhibited completely by 50 mM EDTA, indicating that the reaction is a chemical reaction catalyzed by metal ions. Although NB-506 was not metabolized by cytochrome P-450 isozymes in liver, this drug was glucuronized in mice, rats, and humans, but not in dogs. These results suggest that a species difference in the metabolism of NB-506 occurred in the liver as well as in plasma. There appeared to be species differences in the metabolism of NB-506 in vitro, correlating well with the species-dependent pharmacokinetics of this drug in vivo.

In vivo metabolism of a new anticancer agent, 6-N-formylamino-12, 13-dihydro-1,11-dihydroxy-13-(beta-D-glucopyranosil)5H-indolo [2,3-a]pyrrolo [3,4-c]carbazole-5,7(6H)-dione (NB-506) in rats and dogs: pharmacokinetics, isolation, identification, and quantification of metabolites.

6-N-formylamino-12,13-dihydro-1, 11-dihydroxy-13-(beta-D-glucopyranosil)5H-indolo [2,3-a]pyrrolo [3, 4-c]carbazole-5,7(6H)-dione (NB-506), a potent inhibitor of DNA topoisomerase I, is currently under development for the treatment of cancer. We investigated the pharmacokinetics of NB-506 after i.v. administration in rats and dogs. The plasma concentration of NB-506 decreased biexponentially in rats and dogs with terminal half-lives of approximately 2 h. The area under the curve increased nonlinearly with increasing dose in rats. In contrast, there was a linear relationship between the area under the curve and the dose in dogs. In rats, the plasma clearance decreased with increasing dose up to 187.5 mg/m2 but remained virtually unchanged at the highest dose. The Vdss of NB-506 in rats and dogs was much greater than the plasma volume, indicating that NB-506 is highly distributed to tissue from plasma in these animals. There were marked species differences in the plasma concentrations of ED-501 after i.v. administration of NB-506 to rats and dogs. To better understand the mechanisms of nonlinear pharmacokinetics in rats, in vivo metabolites were determined. After i.v. administration of [14C]NB-506 to rats, two unknown metabolites (RBM-1 and RBM-2), deformyl metabolite (ED-501), and unchanged drug (NB-506) were identified. Mass and NMR spectra analysis revealed that RBM-1 is an 11-O-glucuronide of NB-506 (ED-594) and that RBM-2 is an 11-O-glucuronide of ED-501 (ED-595). In this study, the pharmacokinetics of NB-506 was demonstrated to be nonlinear in rats, probably because of saturation of the enzyme systems catalyzing the deformylation and glucuronidation of NB-506 in rats.

Down regulation of epidermal growth factor receptors in rat hepatocytes treated with clofibric acid.

The effect of clofibric acid (CA), a peroxisome proliferator and a non-genotoxic hepatocarcinogen was investigated on epidermal growth factor (EGF) receptors in hepatocytes of female Sprague-Dawley rats treated at a dose of 9000 ppm in a diet for up to 13 weeks. Hepatocyte plasma membranes were isolated in Weeks 1 and 13, and assayed with [125I]EGF. The binding of EGF to the hepatocyte plasma membranes was reduced in Week 1 as a result of decreased number of low-affinity receptors. The fall of binding capacity was further evident in Week 13, which was associated with decreased numbers of both high- and low-affinity receptors. The equilibrium dissociation constant remained unchanged either in Week 1 or 13. These results were in agreement with previous observations of a decreased hepatocyte response to mitogens after prolonged treatment with CA. This suggested that the CA-associated liver tumor promoting effect is related to its ability to decrease the number of EGF receptors and the resultant aberrant growth environment.

The distribution of G and P types within isolates of bovine rotavirus in Japan.

Various combinations of G type and P type were observed in 76 bovine rotavirus (BRV) strains isolated from 235 diarrheal calves in three prefectures of Japan in 1992-1994. The most prevalent combination was G6:P5 (46/76, 60.5%), followed by G10:P11 (13/76, 17.1%), G6:P11 (7/76, 9.2%) and G10:P5 (5/76, 6.6%). No G6:P1 strain of BRV was recognized from the isolates in the present study, though this type of BRV is well known as a suitable vaccine strain against BRV infection.

Insect prothoracicotropic hormone: a new member of the vertebrate growth factor superfamily.

Prothoracicotropic hormone (PTTH) is a brain neurosecretory protein that controls insect development. PTTH of the silkmoth Bombyx mori is a homodimeric protein, the subunit of which consists of 109 amino acids. Clear-cut sequence similarity to any other proteins has not been observed. By disulfide-bond pattern analysis and modeling of the PTTH structure based on the known three-dimensional (3D) structures of growth factor family with cystine-knot motif, we propose that the PTTH protomer adopts the fold unique to the structural superfamily of the growth factors, beta-nerve growth factor (beta-NGF), transforming growth factor-beta 2 (TGF-beta 2), and platelet-derived growth factor-BB (PDGF-BB). The insect neurohormone PTTH appears to be a member of the growth factor superfamily, sharing a common ancestral gene with the three vertebrate growth factors, beta-NGF, TGF-beta 2 and PDGF-BB.

Osteoplastic changes in attic cholesteatoma.

Eighty-nine cases of attic type cholesteatoma were operated on during a three and a half-year period. Of these, eight cases were characterized by bony tissue proliferation at the aditus ad antrum or mastoid antrum. Sex, age, and hearing levels were not significant in these cases. Bony fixation of the incus and the malleus was seen in six cases. Bony tissue blocked further expansion of attic cholesteatoma at the aditus in four cases, narrowed the epithelial tract to the antrum in two cases, and completely separated the cholesteatoma into two cholesteatomas in two cases. Infectious stimuli, at an early stage of the disease, might stimulate such osteoplastic activity at the aditus. Axial CT scans give useful information regarding structure before surgery.