The function of bone morphogenetic proteins in the human ovary

The gonadotropins, follicle-stimulating hormone (FSH), and luteinizing hormone (LH), are of particular importance in ovarian physiology. However, FSH receptors and LH receptors are not expressed until the secondary follicle stage, indicating that initiation of follicular growth is independent of the gonadotropins. Among many intra-ovarian growth factors, many studies have shown that bone morphogenetic proteins (BMPs) play pivotal roles in regulating the early phases of follicular growth. The BMP system induces the gonadotropin system by modulating gonadotropin receptors in early-stage follicles. Interestingly, the BMP system also prevents precocious maturation of the follicle by suppressing luteinization. Signals provoked by the preovulatory LH surge eliminate BMPs, enabling luteinization to progress. Thus, the BMP system and the gonadotropin system seem to cooperate in regulating follicular development, maturation, and luteinization.     

Cyclin D1 overexpression in Spitz nevi: an immunohistochemical study

The morphologic distinction between Spitz nevus and malignant melanoma can be difficult. Because cyclin D1 has been reported to be overexpressed in malignant melanomas, but not in common acquired nevi, we hypothesized that cyclin D1 might be a useful marker to distinguish Spitz nevi from malignant melanoma. Thus, we assessed for cyclin D1 expression in 11 Spitz nevi (10 compound and 1 intradermal) and 9 malignant melanomas (4 Clark stages I-III and 5 Clark stages IV-V) using an immunohistochemical method and routinely fixed and processed tissues. The cyclin D1 results were arbitrarily divided into three groups: 0% to 10%, >10% to 25%, and >25%. We confirmed the observations reported previously by others that cyclin D1 is expressed in malignant melanomas but not in common acquired nevi. Unexpectedly, a relatively high number of cyclin D1-positive cells (i.e., >10%) was also found in all cases of Spitz nevus. However, unlike malignant melanoma, the cyclin D1 positivity in Spitz nevi was present in a zonal pattern. In other words, the number of cyclin D1-positive cells decreased as the lesion extended more deeply, with the number of positive cells in the reticular dermis being less than that in the papillary dermis. Fluorescence in situ hybridization methods were used to assess amplification of 11q13, the locus harboring the cyclin D1 gene, in four cases of Spitz nevus; all were disomic. Using the antibody MIB-1, we compared cyclin D1 expression to the proliferation rate in Spitz nevi. Despite the high cyclin D1 positivity, all Spitz nevi had a relatively low number of MIB-1-positive cells (mean=3.2%), which was significantly lower than that of malignant melanomas (mean=15.3%) (p < 0.001). Thus, unlike malignant melanoma, there appears to be a dissociation between cyclin D1 overexpression and cell proliferation in Spitz nevi.     

Addition of fexofenadine to a topical corticosteroid reduces the pruritus associated with atopic dermatitis in a 1-week randomized,multicentre, double-blind,placebo-controlled,parallel-group study

BACKGROUND: Fexofenadine, a nonsedating, H1-receptor selective antihistamine, exhibits consistent efficacy and safety in the treatment of allergic rhinitis and urticaria. The pruritus associated with atopic dermatitis is considered to be induced, in part, by histamine. Therefore, we thought that fexofenadine may be useful in the relief of pruritus associated with atopic dermatitis. OBJECTIVE: To compare the efficacy of twice-daily fexofenadine hydrochloride (HCl) 60 mg vs. placebo in reducing the pruritus associated with atopic dermatitis. METHODS: In this randomized, multicentre, double-blind, placebo-controlled study, patients (aged >or= 16 years) with atopic dermatitis underwent a 1-week placebo lead-in period, followed by randomization to fexofenadine HCl 60 mg twice daily or placebo for 1 week. All patients also received topical treatment with 0.1% hydrocortisone butyrate twice daily throughout the study. The primary efficacy endpoint was mean change in pruritus score from baseline. Patients reflectively recorded pruritus scores twice daily (day and night) using a five-point scale (0 = none; 4 = very severe). RESULTS: Fexofenadine (n = 201) significantly decreased the severity of pruritus compared with placebo (n = 199) (mean change in score -0.75 (unadjusted 95% confidence interval [-0.88, -0.62]) vs. -0.5 [-0.62, -0.38], respectively; P = 0.0005). This improvement was seen after just 1 day of treatment (P = 0.039) and was maintained throughout the treatment period (P = 0.019). Compared with placebo, fexofenadine significantly improved both diurnal (P = 0.0001) and nocturnal pruritus (P = 0.013). In addition, significantly more patients in the fexofenadine group experienced a reduction in the ratio of pruritus area to body surface area compared with those in the placebo group (P = 0.007). The incidence of adverse events was low and similar across all treatment groups. CONCLUSIONS: Fexofenadine HCl 60 mg twice daily demonstrated a rapid, significant improvement in the pruritus associated with atopic dermatitis, with a safety profile equivalent to that of placebo.     

A new method for evaluation of fracture healing by echo tracking

Assessment of bone healing on radiographs depends on the volume and radio-opacity of callus at the healing site, but is not necessarily objective, and there are differences of judgment among observers. To overcome this disadvantage, a clinical system was developed to quantify the stiffness of healing fractures of the tibia in patients by the echo tracking (ET) method in a manner similar to a three-point bending test. The purpose of this study was to ensure that the ET system could clinically assess the progress, delay or arrest of healing. The fibular head and the lateral malleolus were supported. A 7.5-MHz ultrasound probe was placed on the proximal and distal fragments and a load of 25 N was applied. Five tracking points were set along the long axis of the ultrasound probe at intervals of 10 mm. With a multiple ET system, two probes measured the displacement of five tracking points on each of the proximal and distal fragments of the tibia, thereby detecting the bending of the two fragments generated by the load. ET angle was defined as the sum of the inclinations of the proximal and distal fragments. Eight tibial fractures in seven patients treated by a cast or internal fixation were measured over time. In patients with radiographically normal healing, the bending angle decreased exponentially over time. However, in patients with nonunion, the angle remained the same over time. It was demonstrated that the ET method could be clinically applicable to evaluate fracture healing as a versatile, quantitative and noninvasive technique. (E-mail: ohnishii-dis@h.u-tokyo.ac.jp)     

Induction of innate immune response and absence of subsequent tolerance to dsRNA in biliary epithelial cells relate to the pathogenesis of biliary atresia

Background/Aims: Biliary epithelial cells (BECs) possess negative regulatory mechanisms of Toll‐like receptor (TLR)‐based tolerance to bacteria (e.g. endotoxin tolerance). Viral infections of the Reoviridae genus with a dsRNA genome are suspected to be part of the aetiology of biliary atresia (BA), but the negative biliary mechanisms remain unexplored. Methods: Cultured human intrahepatic BECs (HIBECs) pretreated with polyinosinic–polycytidylic acid [poly(I:C)] (a synthetic analogue of viral dsRNA) for 24 h were exposed to poly(I:C) in fresh medium. The activation of nuclear factor‐κB (NF‐κB) and the expression of myxovirus resistance protein A (MxA) and tumour necrosis factor‐related apoptosis‐inducing ligand (TRAIL) mRNAs were evaluated. Moreover, after the pretreatment, the transition of these molecules was examined in poly(I:C)‐free conditions. Results: Treatment with poly(I:C) significantly upregulated NF‐κB activity in fresh HIBECs, and pretreatment failed to show tolerance to poly(I:C). The production of MxA and TRAIL was also preserved. Moreover, upregulation in the pretreated HIBECs was well preserved in poly(I:C)‐free medium for at least 72 h. Conclusions: BECs fail to show tolerance to poly(I:C), and once innate immunity is activated it is sustained in poly(I:C)‐free conditions, suggesting that the initiation of the immune response to dsRNA in HIBECs and its presence after the clearance of virus are closely associated with the progression of BA.     

Phosphoprotein analysis for investigation of in vivo relationship between protein phosphatase inhibitory activities and acute hepatotoxicity of microcystin-LR

Microcystin-LR (MCLR) produced by freshwater cyanobacteria is a potent hepatotoxin and inhibits protein serine/threonine phosphatases 1 and 2A (PP1 and PP2A). Okadaic acid (OA) is a similar phosphatase inhibitor, which has less affinity to PP1 than PP2A. MCLR and OA behave similarly with primary culture hepatocytes with the induction of phosphorylation of the cytokeratins, morphological changes, and apoptosis. The purpose of this study was to investigate the in vivo relationship between the protein phosphatase inhibitory activities and the acute hepatotoxicity of MCLR compared to OA. MCLR and OA were intraperitoneally administrated to mice at approximately 220 microg/kg. After 30 min, the liver of only the MCLR-treated mouse was dark-colored and heavier than that of the control mouse. Subsequently, the phosphoproteins of the mouse liver were chemically modified with reversible biotinylation reagent and selectively analyzed by LC/MS/MS. Consequently, the phosphorylated Ser 354 of formyltetrahydrofolate dehydrogenase, which is an abundant enzyme in the liver cytoplasm, was observed in the MCLR- and the OA-treated mice 9.5 and 5.3 times more intensely than in the control mouse respectively, suggesting that MCLR and OA inhibited PP2A and induced the resulting phosphorylation. These results supported the hypothesis that the acute hepatotoxicity is possibly caused by the PP1 inhibition, and not by the PP2A inhibition.     

Pentaketides relating to aspinonene and dihydroaspyrone from a marine-derived fungus, Aspergillus ostianus

Three new pentaketides, aspinotriols A ( 1) and B ( 3) and aspinonediol ( 5), were isolated together with two known compounds, aspinonene ( 7) and dihydroaspyrone ( 9), from the marine fungus Aspergillus ostianus strain 01F313, which was collected in Pohnpei and cultured with bromine-modified artificial seawater. The structures of the new compounds were determined by spectroscopic analyses including 1D and 2D NMR. Although 1 and 3 are diastereomers, they show nearly superimposable (1)H and (13)C NMR spectra. The absolute configurations of compounds 1, 3, 5, and 9 were elucidated by the modified Mosher's method.     

Mcl-1 down-regulation potentiates ABT-737 lethality by cooperatively inducing Bak activation and Bax translocation

The Bcl-2 antagonist ABT-737 targets Bcl-2/Bcl-xL but not Mcl-1, which may confer resistance to this novel agent. Here, we show that Mcl-1 down-regulation by the cyclin-dependent kinase (CDK) inhibitor roscovitine or Mcl-1-shRNA dramatically increases ABT-737 lethality in human leukemia cells. ABT-737 induces Bax conformational change but fails to activate Bak or trigger Bax translocation. Coadministration of roscovitine and ABT-737 untethers Bak from Mcl-1 and Bcl-xL, respectively, triggering Bak activation and Bax translocation. Studies employing Bax and/or Bak knockout mouse embryonic fibroblasts (MEFs) confirm that Bax is required for ABT-737+/-roscovitine lethality, whereas Bak is primarily involved in potentiation of ABT-737-induced apoptosis by Mcl-1 down-regulation. Ectopic Mcl-1 expression attenuates Bak activation and apoptosis by ABT-737+roscovitine, whereas cells overexpressing Bcl-2 or Bcl-xL remain fully sensitive. Finally, Mcl-1 knockout MEFs are extremely sensitive to Bak conformational change and apoptosis induced by ABT-737, effects that are not potentiated by roscovitine. Collectively, these findings suggest down-regulation of Mcl-1 by either CDK inhibitors or genetic approaches dramatically potentiate ABT-737 lethality through cooperative interactions at two distinct levels: unleashing of Bak from both Bcl-xL and Mcl-1 and simultaneous induction of Bak activation and Bax translocation. These findings provide a mechanistic basis for simultaneously targeting Mcl-1 and Bcl-2/Bcl-xL in leukemia.     

Parameter Predicting the Recurrence of Adhesive Small Bowel Obstruction in Patients Managed with a Long Tube

Introduction Some of our patients showed a recurrence of adhesive small bowel obstruction (ASBO) with nonoperative management. The aim of this study was to evaluate the parameters predicting the recurrence of ASBO in patients managed with a long tube. Methods Of 234 patients with ASBO admitted from April 1998 to September 2002, a total of 91 who recovered with nonoperative management after long tube placement were enrolled in this retrospective clinical study. We divided them into two groups for follow-up: the recurrence group and the no-recurrence group. We compared baseline characteristics, the number of previous ASBO admissions, the number of abdominal operations, the interval from the onset of symptoms to long-tube insertion, the duration of long-tube placement, the type of the contrasted intestine through the long tube, the location of the long-tube tip, and the drainage volume through the long tube between the two groups. We then examined the cumulative recurrence rate. Results A significant difference was found in the number of previous ASBO admissions, the duration of long-tube placement (77 hours vs. 43 hours), the contrasted intestine through the long tube, and the location of the long-tube tip. By multivariate analysis, the duration of long-tube placement was an independent parameter predicting the recurrence of ASBO. Conclusions These results suggest that the duration of long-tube placement might serve as a parameter for predicting recurrence of ASBO in patients managed with a long tube.