Chronic Glucocorticoid Exposure Induced an S1PR2-RORγ Axis to Enhance Hepatic Gluconeogenesis in Male Mice

It is well established that chronic glucocorticoid exposure causes hyperglycemia. While glucocorticoid receptor (GR) stimulates hepatic gluconeogenic gene transcription, additional mechanisms are activated by chronic glucocorticoid exposure to enhance gluconeogenesis. We found that chronic glucocorticoid treatment activated sphingosine-1-phosphate (S1P)-mediated signaling. Hepatic knockdown of hepatic S1P receptor 1 (S1PR1) had no effect on chronic glucocorticoid-induced glucose intolerance but elevated fasting plasma insulin levels. In contrast, hepatic S1PR3 knockdown exacerbated chronic glucocorticoid-induced glucose intolerance without affecting fasting plasma insulin levels. Finally, hepatic S1PR2 knockdown attenuated chronic glucocorticoid-induced glucose intolerance and reduced fasting plasma insulin levels. Here, we focused on dissecting the role of S1PR2 signaling in chronic glucocorticoid response on glucose homeostasis. We found that chronic glucocorticoid-induced hepatic gluconeogenesis, gluconeogenic gene expression, and GR recruitment to the glucocorticoid response elements (GREs) of gluconeogenic genes were all reduced in hepatic S1PR2 knockdown male mice. Hepatic S1PR2 knockdown also enhanced glucocorticoid suppression of RAR-related orphan receptor γ (RORγ) expression. Hepatic RORγ overexpression in hepatic S1PR2 knockdown mice restored glucocorticoid-induced glucose intolerance, gluconeogenic gene expression, and GR recruitment to their GREs. Conversely, RORγ antagonist and the reduction of hepatic RORγ expression attenuated such glucocorticoid effects. Thus, chronic glucocorticoid exposure induces an S1PR2-RORγ axis to cooperate with GR to enhance hepatic gluconeogenesis. Overall, this work provides novel mechanisms of and pharmaceutical targets against steroid-induced hyperglycemia.

ARTICLE HIGHLIGHTS

The hepatic integrated stress response suppresses the somatotroph axis to control liver damage in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) can be ameliorated by calorie restriction, which leads to the suppressed somatotroph axis. Paradoxically, the suppressed somatotroph axis is associated with patients with NAFLD and is correlated with the severity of fibrosis. How the somatotroph axis becomes dysregulated and whether the repressed somatotroph axis impacts liver damage during the progression of NAFLD are unclear. Here, we identify a regulatory branch of the hepatic integrated stress response (ISR), which represses the somatotroph axis in hepatocytes through ATF3, resulting in enhanced cell survival and reduced cell proliferation. In mouse models of NAFLD, the ISR represses the somatotroph axis, leading to reduced apoptosis and inflammation but decreased hepatocyte proliferation and exacerbated fibrosis in the liver. NAD+ repletion reduces the ISR, rescues the dysregulated somatotroph axis, and alleviates NAFLD. These results establish that the hepatic ISR suppresses the somatotroph axis to control cell fate decisions and liver damage in NAFLD.

Bifidobacterium longum DS0956 and Lactobacillus rhamnosus DS0508 culture-supernatant ameliorate obesity by inducing thermogenesis in obese-mice

Excessive body fat and the related dysmetabolic diseases affect both developed and developing countries. The aim of this study was to investigate the beneficial role of a bacterial culture supernatant (hereafter: BS) of Lactobacillus and Bifidobacterium and their potential mechanisms of action on white-fat browning and lipolysis. For selection of four candidates among 55 Lactic acid producing bacteria (LAB) from human infant faeces, we evaluated by Oil Red O staining and Ucp1 mRNA quantitation in 3T3-L1 preadipocytes. The expression of browning and lipolysis markers was examined along with in vitro assays. The possible mechanism was revealed by molecular and biological experiments including inhibitor and small interfering RNA (siRNA) assays. In a mouse model, physiological, histological, and biochemical parameters and expression of some thermogenesis-related genes were compared among six experimental groups fed a high-fat diet and one normal-diet control group. The results allow us to speculate that BS treatment promotes browning and lipolysis both in vitro and in vivo. Moreover, the BS may activate thermogenic programs via a mechanism involving PKA-CREB signaling in 3T3-L1 cells. According to our data, we can propose that two LAB strains, Bifidobacterium longum DS0956 and Lactobacillus rhamnosus DS0508, may be good candidates for a dietary supplement against obesity and metabolic diseases; however, further research is required for the development as dietary supplements or drugs.

Bone marrow lesions in knee osteoarthritis: regional differences in tibial subchondral bone microstructure and their association with cartilage degeneration

OBJECTIVE

The aim of this study was to investigate how bone microstructure within bone marrow lesions (BMLs) relates to the bone and cartilage across the whole human tibial plateau.

DESIGN

Thirty-two tibial plateaus from patients with osteoarthritis (OA) at total knee arthroplasty and eleven age-matched non-OA controls, were scanned ex vivo by MRI to identify BMLs and by micro CT to quantitate the subchondral (plate and trabecular) bone microstructure. For cartilage evaluation, specimens were processed histologically.

RESULTS

BMLs were detected in 75% of the OA samples (OA-BML), located predominantly in the anterior-medial (AM) region. In contrast to non-OA control and OA-no BML, in OA-BML differences in microstructure were significantly more evident between subregions. In OA-BML, the AM region contained the most prominent structural alterations. Between-group comparisons showed that the AM region of the OA-BML group had significantly higher histological degeneration (OARSI grade) (P < .0001, P < .05), thicker subchondral plate (P < .05, P < .05), trabeculae that are more anisotropic (P < .0001, P < .05), well connected (P < .05, P = n.s), and more plate-like (P < 0.05, P < 0.05), compared to controls and OA-no BML at this site. Compared to controls, OA-no BML had significantly higher OARSI grade (P < .0001), and lower trabecular number (P < .05).

CONCLUSION

In established knee OA, both the extent of cartilage damage and microstructural degeneration of the subchondral bone were dependent on the presence of a BML. In OA-no BML, bone microstructural alterations are consistent with a bone attrition phase of the disease. Thus, the use of BMLs as MRI image-based biomarkers appear to inform on the degenerative state within the osteochondral unit.

Early complications after percutaneous radiofrequency ablation for hepatocellular carcinoma: an analysis of 1,843 ablations in 1,211 patients in a single centre: experience over 10 years

AIM

To evaluate the incidence of adverse events and associated factors after radiofrequency ablation (RFA) in patients with hepatocellular carcinoma within 30 days.

MATERIALS AND METHODS

The early complications that occurred within 30 days after RFA at a single institution from January 2000 to July 2010 were reviewed in order to evaluate the morbidity, mortality, and risk factors associated with the complications. In total, 1,211 patients (845 men, 70.5%) with a mean age of 68 years (range, 27-88 years) underwent 1,843 RFA procedures.

RESULTS

The overall incidence rate of complications was 6.8% (125 cases). Major complications (n=36, 2%) included liver abscess (n=15, 0.8%), intraperitoneal bleeding (n=8, 0.4%), liver failure (n=5, 0.3%), variceal bleeding (n=3, 0.2%), haemothorax (n=2, 0.1%), cholecystitis (n=2, 0.1%), and bowel perforation (n=1, 0.1%). Among the minor complications (n=89, 4.8%), the most common was the post RFA syndrome accompanied by pain and fever (n=75, 4.1%). Other minor complications included significant pleural effusion (n=7, 0.4%), skin wound infection (n=4, 0.2%), and thermal injuries to the skin (n=3, 0.2%). Procedural infections significantly increased with tumour size (OR=1.379; 95% confidence interval [CI], 1.191-1.579; p<0.001), and multiple overlapping ablations (OR=1.118; 95% CI, 1.019-1.227, p=0.018). Thrombocytopenia (<50,000/μl), prothrombin time, and serum albumin level were significantly associated with post-RFA bleeding episodes (p=0.041, p=0.021, and p=0.003, respectively). The overall mortality rate was 0.3% (three cases of hepatic failure, two case of sepsis, and one case of renal failure).

CONCLUSIONS

RFA is a safe and effective local treatment for hepatocellular carcinoma. Careful selection of patients and appropriate RFA planning could decrease procedural mortality and morbidity.

Glechoma hederacea Suppresses RANKL-mediated Osteoclastogenesis

Glechoma hederacea (GH), commonly known as ground-ivy or gill-over-the-ground, has been extensively used in folk remedies for relieving symptoms of inflammatory disorders. However, the molecular mechanisms underlying the therapeutic action of GH are poorly understood. Here, we demonstrate that GH constituents inhibit osteoclastogenesis by abrogating receptor activator of nuclear κ-B ligand (RANKL)-induced free cytosolic Ca(2+) ([Ca(2+)]i) oscillations. To evaluate the effect of GH on osteoclastogenesis, we assessed the formation of multi-nucleated cells (MNCs), enzymatic activity of tartrate-resistant acidic phosphatase (TRAP), expression of nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), and [Ca(2+)]i alterations in response to treatment with GH ethanol extract (GHE) in primarily cultured bone marrow-derived macrophages (BMMs). Treatment of RANKL-stimulated or non-stimulated BMMs with GHE markedly suppressed MNC formation, TRAP activity, and NFATc1 expression in a dose-dependent manner. Additionally, GHE treatment induced a large transient elevation in [Ca(2+)]i while suppressing RANKL-induced [Ca(2+)]i oscillations, which are essential for NFATc1 activation. GHE-evoked increase in [Ca(2+)]i was dependent on extracellular Ca(2+) and was inhibited by 1,4-dihydropyridine (DHP), inhibitor of voltage-gated Ca(2+) channels (VGCCs), but was independent of store-operated Ca(2+) channels. Notably, after transient [Ca(2+)] elevation, treatment with GHE desensitized the VGCCs, resulting in an abrogation of RANKL-induced [Ca(2+)]i oscillations and MNC formation. These findings demonstrate that treatment of BMMs with GHE suppresses RANKL-mediated osteoclastogenesis by activating and then desensitizing DHP-sensitive VGCCs, suggesting potential applications of GH in the treatment of bone disorders, such as periodontitis, osteoporosis, and rheumatoid arthritis.

Abstract P5-07-04: Aurora kinase regulates PKC-mediated MMP-9 expression and invasion in MCF-7 breast cancer cells

Aurora kinase is a novel family of serine/threonine kinases. Elevated expression of aurora kinase A and B is observed in many tumor cells, and dysregulation of aurora kinase has been linked to tumorigenesis. Therefore, a number of studies focused in their oncogene activities as anti-tumor targets. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix (ECM) and it is important process for breast cancer cell invasion. MMP-9 can be stimulated by activation of various cellular signaling pathways including protein kinase C (PKC), and mitogen-activated protein kinase (MAPKs), activator protein-1 (AP-1) and nuclear factor-kappaB (NF-κB) signaling pathways. Here, we show that 12-O-tetradecanoylphorbol-13-acetate (TPA), a directly PKC activator stimulation resulted in an up-regulation and phosphorlyation of aurora kinases in MCF-7 breast cancer cells. Also, Results showed that inhibition of the aurora kinases suppressed TPA-induced MMP-9 secretion/expression and cell invasion through suppression of NF-κB, AP-1, and MAPKs in MCF-7 breast cancer cell. In conclusion, this study provides new insight into the novel role of aurora kinase for expression of MMP-9 by TPA and regulation of aurora kinase by TPA through MAPKs signaling pathway.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-07-04.

SPA0355, a thiourea analogue, inhibits inflammatory responses and joint destruction in fibroblast-like synoviocytes and mice with collagen-induced arthritis

BACKGROUND AND PURPOSE

NF-κB has been implicated as a therapeutic target for the treatment of rheumatoid arthritis. We previously synthesized a thiourea analogue, SPA0355, which suppressed NF-κB activity. Here we have assessed the anti-inflammatory and anti-arthritic effects of SPA0355.

EXPERIMENTAL APPROACH

We evaluated the effects of SPA0355 on human rheumatoid fibroblast-like synoviocytes in vitro and on collagen-induced arthritis (CIA) in mice in vivo.

KEY RESULTS

In vitro experiments demonstrated that SPA0355 suppressed chemokine production, matrix metalloproteinase secretion and cell proliferation induced by TNF-α in rheumatoid fibroblast-like synoviocytes. In addition, SPA0355 inhibited osteoclast differentiation induced by macrophage colony-stimulating factor and the receptor activator of NF-κB ligand, in bone marrow macrophages. Mice with CIA that were pretreated with SPA0355 had a lower cumulative disease incidence and severity of arthritis, based on hind paw thickness, radiological and histopathological findings, and inflammatory cytokine levels, than mice treated with vehicle. Mice treated with SPA0355, after the onset of CIA, also showed significantly decreased disease incidence and joint oedema. The in vitro and in vivo protective effects of SPA0355 were mediated by inhibition of the NF-κB signalling pathway.

CONCLUSION AND IMPLICATIONS

Taken together, these results suggested that using SPA0355 to block the NF-κB pathway in rheumatoid joints reduced both the inflammatory responses and tissue destruction. Therefore, SPA0355 may have therapeutic value in preventing or delaying joint destruction in patients with rheumatoid arthritis.

Inhibition of VEGF blocks TGF-beta1 production through a PI3K/Akt signalling pathway

Vascular endothelial growth factor (VEGF) is a mediator of airway inflammation and remodelling in asthma. Transforming growth factor (TGF)-beta(1) plays pivotal roles in diverse biological processes, including tissue remodelling and repair in a number of chronic lung diseases. However, there are few studies elucidating the interactions between VEGF and TGF-beta(1) in allergic airway disease. A murine model of allergic airway disease was used to define the mechanism by which VEGF induces subepithelial fibrosis and to investigate a potential relationship between VEGF and TGF-beta(1) and the mechanisms by which VEGF signalling regulates TGF-beta(1) expression in allergic airway disease. The ovalbumin (OVA)-inhaled murine model revealed the following typical pathophysiological features of allergic airway disease in the lungs: increased numbers of inflammatory cells of the airways, airway hyperresponsiveness, increased peribronchial fibrosis, and increased levels of VEGF and TGF-beta(1). Administration of VEGF inhibitors reduced the pathophysiological signs of allergic airway disease and decreased the increased TGF-beta(1) levels and peribronchial fibrosis, including phosphoinositide 3-kinase (PI3K) activity after OVA inhalation. In addition, the increased TGF-beta(1) levels and collagen deposition after OVA inhalation were decreased by administration of PI3K inhibitors. These results suggest that inhibition of vascular endothelial growth factor attenuates peribronchial fibrosis, at least when mediated by regulation of transforming growth factor-beta(1) expression through phosphoinositide 3-kinase/Akt pathway in a murine model of allergic airway disease.

CT halo sign: the spectrum of pulmonary diseases

The CT halo sign indicates ground glass attenuation surrounding a pulmonary nodule on CT. Although it was initially proposed as an early, specific finding of invasive pulmonary aspergillosis, it can be caused by many other pathological conditions such as infection, neoplastic and inflammatory diseases. The halo of ground glass attenuation pathologically represents pulmonary haemorrhage, tumour infiltration, or non-haemorrhagic inflammatory processes. Although non-specific, this sign is important because the clinical setting and associated radiological features may give a clue to the differential diagnosis. In this review, we demonstrate the spectrum of pulmonary diseases showing the "CT halo sign" on thin-section CT and discuss their radiological and clinical features.

The most useful findings for diagnosing acute appendicitis on contrast-enhanced helical CT

PURPOSE

To evaluate the most useful findings to look for in diagnosing acute appendicitis on contrast-enhanced helical CT.

MATERIAL AND METHODS

Appendiceal helical CT scans with intravenous contrast administration (abdomen, 7-mm collimation; abdominopelvic junction, 5-mm collimation) of 71 patients with surgically proven acute appendicitis and 167 patients with alternative diagnoses were reviewed retrospectively. Three radiologists analyzed the following parameters: enlarged appendix (>6 mm in diameter), appendiceal wall thickening, appendiceal wall enhancement, no identification of the appendix, appendicolith(s), appendiceal intraluminal air, intramural air, extraluminal air, periappendiceal fat stranding, extraluminal fluid, phlegmon, abscess, lymphadenopathy, segmental terminal ileal wall thickening, focal cecal apical thickening, focal colonic wall thickening, and segmental colonic wall thickening. The features that best distinguished appendicitis from alternative diagnoses were selected with stepwise logistic regression analysis.

RESULTS

Nine CT findings distinguished acute appendicitis from alternative diagnoses (P < 0.05): enlarged appendix (R = 0.739), appendiceal wall thickening (R = 0.525), periappendiceal fat stranding (R = 0.414), appendiceal wall enhancement (R = 0.404), focal cecal apical thickening (R = 0.171), appendicolith(s) (R = 0.157), extraluminal air (R = 0.050), intramural air (R = 0.043), and phlegmon (R = 0.030). Enlarged appendix (sensitivity, 93%; specificity, 92%), appendiceal wall thickening (sensitivity, 66%; specificity, 96%), periappendiceal fat stranding (sensitivity, 87%; specificity, 74%), and appendiceal wall enhancement (sensitivity, 75%; specificity, 85%) showed the statistically most significant association with acute appendicitis.

CONCLUSION

On 5-mm-section contrast-enhanced helical CT examinations, enlarged appendix, appendiceal wall thickening, periappendiceal fat stranding, and appendiceal wall enhancement were the most useful findings for diagnosing acute appendicitis.

The most useful findings for diagnosing acute appendicitis on contrast-enhanced helical CT

PURPOSE

To evaluate the most useful findings to look for in diagnosing acute appendicitis on contrast-enhanced helical CT.

MATERIAL AND METHODS

Appendiceal helical CT scans with intravenous contrast administration (abdomen, 7-mm collimation; abdominopelvic junction, 5-mm collimation) of 71 patients with surgically proven acute appendicitis and 167 patients with alternative diagnoses were reviewed retrospectively. Three radiologists analyzed the following parameters: enlarged appendix (>6 mm in diameter), appendiceal wall thickening, appendiceal wall enhancement, no identification of the appendix, appendicolith(s), appendiceal intraluminal air, intramural air, extraluminal air, periappendiceal fat stranding, extraluminal fluid, phlegmon, abscess, lymphadenopathy, segmental terminal ileal wall thickening, focal cecal apical thickening, focal colonic wall thickening, and segmental colonic wall thickening. The features that best distinguished appendicitis from alternative diagnoses were selected with stepwise logistic regression analysis.

RESULTS

Nine CT findings distinguished acute appendicitis from alternative diagnoses (P < 0.05): enlarged appendix (R = 0.739), appendiceal wall thickening (R = 0.525), periappendiceal fat stranding (R = 0.414), appendiceal wall enhancement (R = 0.404), focal cecal apical thickening (R = 0.171), appendicolith(s) (R = 0.157), extraluminal air (R = 0.050), intramural air (R = 0.043), and phlegmon (R = 0.030). Enlarged appendix (sensitivity, 93%; specificity, 92%), appendiceal wall thickening (sensitivity, 66%; specificity, 96%), periappendiceal fat stranding (sensitivity, 87%; specificity, 74%), and appendiceal wall enhancement (sensitivity, 75%; specificity, 85%) showed the statistically most significant association with acute appendicitis.

CONCLUSION

On 5-mm-section contrast-enhanced helical CT examinations, enlarged appendix, appendiceal wall thickening, periappendiceal fat stranding, and appendiceal wall enhancement were the most useful findings for diagnosing acute appendicitis.

Solid and papillary epithelial neoplasm of the pancreas with peritoneal metastasis and its recurrence: a case report

Solid and papillary epithelial neoplasm of the pancreas is a low-grade malignant tumor, generally occurring as a slowly growing upper abdominal mass in a young female. With complete excision, the prognosis is good. Malignant behavior with metastasis does occur, but the incidence is very low. We report a young woman who had this neoplasm in the pancreatic tail with peritoneal seeding and its recurrence.

Proximal gastrectomy and jejunal pouch interposition: radiographic evaluation of postoperative findings

BACKGROUND

We assessed the postoperative findings of proximal gastrectomy and jejunal pouch interposition with contrast radiography.

METHODS

Eleven patients with proximal gastrectomy and jejunal pouch interposition for proximal gastric carcinoma underwent contrast radiography. We evaluated the radiographic findings of the remnant stomach and interposed jejunal pouch.

RESULTS

The interposed jejunal pouch showed good expansion, and the motility of the remnant gastric antrum was normal in all patients. One patient had significant lumenal narrowing of the esophageal pouch anastomotic site. Leak at the anastomotic site was not found. Reflux into the esophagus from the pouch was observed in two patients. Gastric emptying time was considerably delayed in two patients.

CONCLUSION

Follow-up upper gastrointestinal series of the proximal gastrectomy and jejunal pouch interposition showed different postoperative findings. Awareness of the normal and abnormal findings is essential in the accurate postoperative evaluation of these patients.

A novel plant kinesin-related protein specifically associates with the phragmoplast organelles

In higher plants, the formation of the cell plate during cytokinesis requires coordinated microtubule (MT) reorganization and vesicle transport in the phragmoplast. MT-based kinesin motors are important players in both processes. To understand the mechanisms underlying plant cytokinesis, we have identified AtPAKRP2 (for Arabidopsis thaliana phragmoplast-associated kinesin-related protein 2). AtPAKRP2 is an ungrouped N-terminal motor kinesin. It first appeared in a punctate pattern among interzonal MTs during late anaphase. When the phragmoplast MT array appeared in a mirror pair, AtPAKRP2 became more concentrated near the division site, and additional signal could be detected elsewhere in the phragmoplast. In contrast, the previously identified AtPAKRP1 protein is associated specifically with bundles of MTs in the phragmoplast at or near their plus ends. Localization of the tobacco homolog(s) of AtPAKRP2 was altered by treatment of brefeldin A in BY-2 cells. We discuss the possibility that AtPAKRP1 plays a role in establishing and/or maintaining the phragmoplast MT array, and AtPAKRP2 may contribute to the transport of Golgi-derived vesicles in the phragmoplast.

A novel plant kinesin-related protein specifically associates with the phragmoplast organelles

In higher plants, the formation of the cell plate during cytokinesis requires coordinated microtubule (MT) reorganization and vesicle transport in the phragmoplast. MT-based kinesin motors are important players in both processes. To understand the mechanisms underlying plant cytokinesis, we have identified AtPAKRP2 (for Arabidopsis thaliana phragmoplast-associated kinesin-related protein 2). AtPAKRP2 is an ungrouped N-terminal motor kinesin. It first appeared in a punctate pattern among interzonal MTs during late anaphase. When the phragmoplast MT array appeared in a mirror pair, AtPAKRP2 became more concentrated near the division site, and additional signal could be detected elsewhere in the phragmoplast. In contrast, the previously identified AtPAKRP1 protein is associated specifically with bundles of MTs in the phragmoplast at or near their plus ends. Localization of the tobacco homolog(s) of AtPAKRP2 was altered by treatment of brefeldin A in BY-2 cells. We discuss the possibility that AtPAKRP1 plays a role in establishing and/or maintaining the phragmoplast MT array, and AtPAKRP2 may contribute to the transport of Golgi-derived vesicles in the phragmoplast.

Altered mRNA expression of sialyltransferase in squamous cell carcinomas of the cervix

OBJECTIVE

Increased sialylation has been reported in various kinds of cancers, but to date, sialylation of cervical carcinoma has never been evaluated. This study of the changes in messenger ribonucleic acid (mRNA) expression of the four sialyltransferases (ST3Gal I, ST3Gal III, ST3Gal IV, and ST6Gal I) in a normal cervix and that with FIGO stage IB1 squamous cell carcinoma was undertaken to assess the extent of sialylation associated with establishment of the carcinoma.

METHODS

Alterations in ST mRNA expression in FIGO IB1 cervical cancer (n = 30) and normal cervixes (n = 30) were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

ST6Gal I expression was enhanced in squamous cell carcinoma of the cervix (P = 0.026, Mann-Whitney U test), but mRNA expression from the other three STs (ST3Gal I, ST3Gal III, and ST3Gal IV) was significantly down-expressed in squamous cell carcinoma of the cervix compared to the normal cervix (P = 0.003, P < 0.001, and P = 0.001, respectively). High ST6Gal I expression was associated with more invasive properties of cervical cancer, such as deep stromal invasion, lymph or vascular space involvement, and poor differentiation (P = 0.010, P < 0.001, P < 0.001, respectively).

CONCLUSIONS

A combination of enhanced ST6Gal I mRNA expression and decreased mRNA expression from ST3Gal I, ST3Gal III, and ST3Gal IV might be important in cervical cancer. Future studies will investigate whether RT-PCR detection of the expression of these enzymes can be helpful for prognostic purposes.

Inhibitory effects of anti-inflammatory drugs on interleukin-6 bioactivity

Interleukin-6 (IL-6) is known as a proinflammatory cytokine involved in immune response, inflammation, and hematopoiesis. Inhibitory effects of anti-inflammatory drugs on IL-6 bioactivity using IL-6-dependent hybridoma have been evaluated. Three out of 16 nonsteroidal anti-inflammatory drugs (NSAIDs) showed IC50 values of less than 100 microM, which were in the order of oxyphenylbutazone hydrate (IC50=7.5 microM)>meclofenamic acid sodium salt (31.9 microM)>sulindac (74.9 microM). Steroidal anti-inflammatory drugs (SAIDs) exhibited significant inhibitory effects at 100 microM on the IL-6 bioactivity, and their inhibitory potencies were in the order of budesonide (IC50=2.2 microM)>hydrocortisone 21-hemisuccinate (6.7 microM), prednisolone (7.5 microM), betamethasone (10.9 microM)>dexamethasone (18.9 microM) and triamcinolone acetonide (24.1 microM). The results would provide an additional mechanism by which anti-inflammatory drugs display their anti-inflammatory and immunosuppressive effects at higher concentrations.

Polarization-resolved output analysis of X-ray multiple-wave interaction

The polarization suppression of the interfering components in X-ray multiple-wave interaction is observed for the first time by using a polarization analyzer with an arbitrary inclination of the diffraction plane with respect to that of the investigated crystal. The condition for total suppression of the multiple-wave interaction outside the investigated crystals by a polarization analyzer is derived theoretically from the modified Born approximation. By means of the partial suppression of the strong interfering component, the increase in the visibility of multiple-wave interference is experimentally and theoretically demonstrated. The proposed experimental polarization-resolved technique provides an operational way to enhance the visibility of X-ray multiple-wave interaction outside the investigated crystals for direct phase determination.

Photochemically removable silyl protecting groups

Several o-phenol-containing alkoxyvinylsilanes were prepared and their photochemistry was investigated. These materials were prepared via hydrosilylation of the corresponding o-acetoxy arylacetylenes. Two major classes of photochemical processes were identified in these reactants: trans-->cis isomerization, leading to an intramolecular nucleophilic substitution process at silicon, and 1,5-silyl shift, leading to an unsymmetrical dialkoxysilane. The major outcome of this work is a novel class of photochemically removable protecting groups. Two alkyl substitutions on silicon, the dimethyl and diisopropyl, were examined. The latter is more stable and is preferred for protecting groups that must tolerate multiple steps or reagents. Protection of alcohols is generally performed starting with the arylethynyl acetate, which can be subjected to hydrosilylation, alcohol substitution, and acetate deprotection without isolation of intermediates. Two groups were studied in detail, the phenol and 2-naphthol vinyl silane derivatives. A variety of primary and secondary alcohols were protected with these reagents. These groups can be deprotected cleanly and in high yield by irradiation from 250 to 350 nm.

Design and synthesis of novel fluorocyclopropanoid nucleosides

Novel fluorocyclopropanoid nucleosides were designed, synthesized and evaluated their antiviral activities against poliovirus, HSV, HIV, and HBV.

Hepatocyte growth factor (HGF) activator expressed in hair follicles is involved in in vitro HGF-dependent hair follicle elongation

Hepatocyte growth factor (HGF), a paracrine factor secreted by follicular papilla cells, acts on neighboring follicular epithelial cells to promote follicular growth, while HGF activator is a serine proteinase, which converts inactive single-chain HGF to the active heterodimeric form. In this study, using 3' rapid amplification of cDNA end/nested polymerase chain reaction (3' RACE/nested PCR) and immunoblotting, we confirmed the expression of HGF activator in both cultured human follicular papilla cells and outer root sheath cells. HGF activator mRNA was expressed in all of the isolated 15 anagen hair follicles taken from the scalps of seven individuals. In an organ culture system, single-chain HGF stimulated hair follicle elongation, which was partially inhibited by aprotinin, a serine proteinase inhibitor (P<0.01). These results suggest that single-chain HGF secreted from follicular papilla cells is converted to an active heterodimeric form by intrinsic HGF activator and that the resultant active form of HGF stimulates hair growth.

Pancreatitis due to Ascaris lumbricoides: second occurrence after 2 years

Pancreatitis is a common disease in the United States, with the most likely etiologies being biliary tract disease and alcohol use. Infections with parasites such as Ascaris lumbricoides comprise a small percentage of pancreatitis cases in the United States, but they are a common etiology in developing countries. In the United States, the incidence of pancreatic and biliary ascariasis has been increasing because of the migration of people from endemic countries, as well as increased travel by Americans to such countries. Patients treated for this roundworm can have reinvasion for the same reasons. We report the case of a patient with two episodes of pancreatitis due to A. lumbricoides 2 years apart.

Molecular and pharmacological aspects of antiestrogen resistance

Endocrine therapy is effective in approximately one-third of all breast cancers and up to 80% of tumors that express both estrogen and progesterone receptors. Despite the low toxicity, good overall response rates, and additional benefits associated with its partial agonist activity, most Tamoxifen-responsive breast cancers acquire resistance. The development of new antiestrogens, both steroidal and non-steroidal, provides the opportunity for the development of non-cross-resistant therapies and the identification of additional mechanisms of action and resistance. Drug-specific pharmacologic mechanisms may confer a resistance phenotype, reflecting the complexities of both tumor biology/pharmacology and the molecular endocrinology of steroid hormone action. However, since all antiestrogens will be effective only in cells that express estrogen receptors (ER), many mechanisms will likely be directly related to ER expression and signaling. For example, loss of ER expression/function is likely to confer a cross-resistance phenotype across all structural classes of antiestrogens. Altered expression of ERalpha and ERbeta, and/or signaling from transcription complexes driven by these receptors, may produce drug-specific resistance phenotypes. We have begun to study the possible changes in gene expression that may occur as cells acquire resistance to steroidal and non-steroidal antiestrogens. Our preliminary studies implicate the altered expression of several estrogen-regulated genes. However, resistance to antiestrogens is likely to be a multigene phenomenon, involving a network of interrelated signaling pathways. The way in which this network is adapted by cells may vary among tumors, consistent with the existence of a highly plastic and adaptable genotype within breast cancer cells.

Identification of a phragmoplast-associated kinesin-related protein in higher plants

The phragmoplast executes cytokinesis in higher plants. The major components of the phragmoplast are microtubules, which are arranged in two mirror-image arrays perpendicular to the division plane [1]. The plus ends of these microtubules are located near the site of the future cell plate. Golgi-derived vesicles are transported along microtubules towards the plus ends to deliver materials bound for the cell plate [2] [3]. During cell division, rapid microtubule reorganization in the phragmoplast requires the orchestrated activities of microtubule motor proteins such as kinesins. We isolated an Arabidopsis cDNA clone of a gene encoding an amino-terminal motor kinesin, AtPAKRP1, and have determined the partial sequence of its rice homolog. Immunofluorescence experiments with two sets of specific antibodies revealed consistent localization of AtPAKRP1 and its homolog in Arabidopsis and rice cells undergoing anaphase, telophase and cytokinesis. AtPAKRP1 started to accumulate along microtubules towards the spindle midzone during late anaphase. Once the phragmoplast microtubule array was established, AtPAKRP1 conspicuously localized to microtubules near the future cell plate. Our results provide evidence that AtPAKRP1 is a hitherto unknown motor that may take part in the establishment and/or maintenance of the phragmoplast microtubule array.

One-pot construction of medium- and large-sized ring substituted furans. Efficient conversion to dibenzofurans, coumestans, and 4-pyrones

New efficient synthesis of medium- and large-sized ring substituted furans is achieved by 1,3-dicarbonyl compounds with vinyl sulfides in the presence of Ag(2)CO(3)/Celite (Fétizon's reagent) in a one-pot procedure. The synthesized furans can be further converted to biologically interesting compounds such as dibenzofurans, coumestans, benzofuroquinolinone, and 4-pyrone.

Radiological features of leiomyomatous tumors of the colon and rectum

PURPOSE

The purpose of this study was to evaluate the radiological features of 12 pathologically proven cases of colorectal leiomyomatous tumors.

METHOD

A retrospective analysis of radiologic findings was performed in 12 patients with pathologically proven colorectal leiomyomatous tumors (2 leiomyomas and 10 leiomyosarcomas). Available radiologic studies included abdominal CT scans in 11 patients, double contrast barium studies in 4, and pelvic MRI in 1. On imaging, we evaluated the size, tumor margin (smooth or lobulated), morphologic appearance, growth patterns (endocolic, exocolic, or combined), contrast enhancement patterns, presence or absence of calcification within the tumors, and metastasis.

RESULTS

The involved tumor sites were the colon in 2 patients and the rectum in 10. The mean tumor size was 7.9 cm (range 2-15 cm): It was 3.5 cm in leiomyomas and 8.8 cm in leiomyosarcomas. On imaging studies, the tumor margin was smooth in three patients and lobulated in nine, with endocolic growth in one, exocolic in four, and combined in the remaining seven. Eight of the 12 tumors showed varying degrees of internal necrosis with heterogeneous contrast enhancement. Dystrophic calcification was noted in five patients. Metastasis was seen in the liver in three patients at the time of initial diagnosis, and lymphadenopathy was noted in two patients (paraaortic space in one and perirectal space in two).

CONCLUSION

Although rare, the diagnosis of leiomyomatous tumor may be suggested especially when the tumor occurring in the colorectum shows exocolic growth or calcification with varying degree of internal necrosis.

Hair cycle-dependent expression of hepatocyte growth factor (HGF) activator, other proteinases, and proteinase inhibitors correlates with the expression of HGF in rat hair follicles

We previously reported that hepatocyte growth factor (HGF) had a stimulatory effect on hair growth in vivo and in vitro. The secreted inactive form of HGF is processed into an active form by serine proteinases such as HGF activator and urokinase. The mRNA expressions of various proteinases and their inhibitors in relation to HGF activation in hair growth were examined using animals with a synchronous hair cycle. Total RNA were extracted from the anterior dorsal skin of rats in different hair cycle stages, and mRNA expressions of the specific genes were compared using semiquantitative reverse transcription polymerase chain reaction. The mRNA of HGF, HGF activator, urokinase, plasminogen activator inhibitor (PAI)-1, nexin-1, matrix metalloproteinase (MMP)-2, and tissue inhibitor of metalloproteinase (TIMP)-1 were expressed strongly in anagen tissue and slightly in telogen tissue. Moreover, topical application of 1% minoxidil sulfate to the anterior dorsal skin of rats in telogen stimulated hair growth and increased the mRNA expressions of HGF and MMP-2. These findings suggest that some proteinases and their inhibitors, strongly expressed in anagen, may act as hair growth regulatory molecules, and may also be involved in processing the latent form of HGF.

Systematic mutation analysis of the catechol O-methyltransferase gene as a candidate gene for schizophrenia

OBJECTIVE

Catechol O-methyltransferase (COMT) is involved in the degradation of catecholamine neurotransmitters. Recent linkage studies of schizophrenia and molecular studies of velocardiofacial syndrome suggest that the COMT gene might be a candidate gene for schizophrenia.

METHOD

The authors systematically searched for mutations and microdeletion of the COMT gene in 177 Chinese schizophrenic patients from Taiwan; 99 comparison subjects were also studied.

RESULTS

Five molecular variants were identified: c.186C > T at exon 3, c.408C > G at exon 4, c.472G > A at exon 4, c.597G > A at exon 5, and c.821-827insC at the 3' untranslated region. However, no differences in the genotype and haplotype frequencies of these molecular variants between the schizophrenic and comparison subjects were detected. Furthermore, no microdeletion was identified among the patients.

CONCLUSIONS

These data suggest that the COMT gene does not play a major role in the pathogenesis of schizophrenia, and the genotypic overlap between schizophrenia and velocardiofacial syndrome was rare in this cohort.

Evaluation of solid breast lesions with power Doppler sonography

PURPOSE

We compared the abilities of power and conventional color Doppler sonography to depict the vascularity of solid breast lesions and evaluated the usefulness of power Doppler sonography in differentiating between benign and malignant breast lesions.

METHODS

One hundred two solid breast lesions (59 benign and 43 malignant lesions) were studied with power and color Doppler sonography. Power and color Doppler sonograms were retrospectively compared for the depiction of blood flow signals. Power Doppler images were also reviewed for the amount of Doppler signals, pattern of vascularity, and morphology of vessels. The sensitivity, specificity, and accuracy of the 2 techniques were calculated.

RESULTS

Compared with color Doppler sonography, power Doppler sonography depicted flow superiorly in 61 cases (60%) and equally in 41 cases (40%). On power Doppler sonography, the incidence of marked blood flow in malignant lesions (65%) was higher than that in benign lesions (39%). The pattern of vascularity was predominantly central (86%) and/or penetrating (65%) more often in malignant lesions than in benign lesions (51% and 34%, respectively). Branching (56%) and disordered vessels (42%) were seen more often in malignant lesions than in benign lesions (22% and 8%, respectively). The sensitivity, specificity, and accuracy in diagnosing malignancy were 64%, 76%, and 71%, respectively, for power Doppler sonography and 77%, 76%, and 76% for color Doppler sonography.

CONCLUSIONS

Power Doppler sonography was more sensitive than color Doppler sonography in the detection of flow in solid breast lesions. Although power Doppler sonography was not more effective in diagnosing malignant lesions, central and penetrating vascularity patterns and branching and disordered vessels seem to be helpful findings in predicting malignancy.

Arabidopsis thaliana 'extra-large GTP-binding protein' (AtXLG1): a new class of G-protein

Heterotrimeric GTP-binding proteins, composed of alpha, beta, and gamma subunits, are involved in signal transduction pathways in animal and plant systems. In plants, physiological analyses implicate heterotrimeric G-proteins in ion channel regulation, light signaling, and hormone and pathogen responses. However, only one class of plant G alpha genes has been identified to date. We have cloned a novel gene, 'Arabidopsis thaliana extra-large GTP-binding protein' (AtXLG1). AtXLG1 appears to be a member of a small gene family and is transcribed in all tissues assayed: roots, leaves, stems, flowers, and fruits. The conceptually translated protein from AtXLG1 is 99 kDa, twice as large as typical G alpha proteins. The carboxy-terminal half of the AtXLG1 protein has significant homology to animal and plant G alpha proteins. This region includes a GTP-binding domain, a predicted helical domain, and an aspartate/glutamate-rich loop, which are characteristics of G alpha's. Despite the absence of some of the amino acids implicated in GTP binding and hydrolysis by crystallographic and mutational analyses of mammalian G alpha's, recombinant AtXLG1 binds GTP with specificity. The amino-terminal region of AtXLG1 contains domains homologous to the bacterial TonB-box, which is involved in energy transduction between the inner and outer bacterial membranes, and to zinc-finger proteins. Given the unique structure of AtXLG1, it will be of interest to uncover its physiological functions.

Cultural influences on caregiving burden: cases of Koreans and Americans

This study compared cultural influences on caregiver burdens of Korean adult children and American adult children caring for parents with dementia, and identified culturally specific values, norms, and customs associated with low or high burden. The findings suggested that the low burden of the Korean caregivers was associated with extended family support and high filial responsibility while that of the American caregivers was related to the use of formal services and high gratification from caregiving. Obversely, the high burden of the Koreans was seen to be associated with limited formal services outside the family and low gratification from caregiving for in-laws while that of the Americans was suggested to be due to limited extended family support and low filial responsibility. Needs for culturally-appropriate interventions are discussed.

Guard cells possess a calcium-dependent protein kinase that phosphorylates the KAT1 potassium channel

Increasing evidence suggests that changes in cytosolic Ca2+ levels and phosphorylation play important roles in the regulation of stomatal aperture and as ion transporters of guard cells. However, protein kinases responsible for Ca2+ signaling in guard cells remain to be identified. Using biochemical approaches, we have identified a Ca(2+)-dependent protein kinase with a calmodulin-like domain (CDPK) in guard cell protoplasts of Vicia faba. Both autophosphorylation and catalytic activity of CDPK are Ca2+ dependent. CDPK exhibits a Ca(2+)-induced electrophoretic mobility shift and its Ca(2+)-dependent catalytic activity can be inhibited by the calmodulin antagonists trifluoperazine and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide. Antibodies to soybean CDPK alpha cross-react with CDPK. Micromolar Ca2+ concentrations stimulate phosphorylation of several proteins from guard cells; cyclosporin A, a specific inhibitor of the Ca(2+)-dependent protein phosphatase calcineurin enhances the Ca(2+)-dependent phosphorylation of several soluble proteins. CDPK from guard cells phosphorylates the K+ channel KAT1 protein in a Ca(2+)-dependent manner. These results suggest that CDPK may be an important component of Ca2+ signaling in guard cells.

Revised Relative and Absolute Stereochemistry of (+)-Purpurin

The relative and absolute stereochemistries of (+)-purpurin (3), a flavanone natural product from Tephrosia, were determined to be 2S,7aR,10S,10aS by synthesis from semiglabrin in conjunction with X-ray crystallographic analysis.

Lack of allelic association between 102T/C polymorphism of serotonin receptor type 2A gene and schizophrenia in Chinese

Recent studies have reported an association between a 102T/C polymorphism of serotonin receptor type 2A gene (5-HT2A) and schizophrenia. In addition, an association was detected between a 102T/C polymorphism of the 5-HT2A receptor gene and drug response to clozapine in the treatment of schizophrenic patients. These studies suggest an important role of the 5-HT2A gene in schizophrenia. To study the possible involvement of the 5-HT2A gene in the pathogenesis of schizophrenia, a case-control association study was carried out in a Chinese population from Taiwan. No significant differences of genotype distributions, allele frequencies and homozygosity were detected between schizophrenic patients (n = 177) and nonpsychiatric controls (n = 98). When subjects were divided into subgroups according to sex, still no differences of allele frequencies or genotype distributions were noted between patients and controls. Our data do not support an allelic association between the 102T/C polymorphism of the 5-HT2A receptor gene and schizophrenia in Chinese population.

Cultural differences in caregiving motivations for demented parents: Korean caregivers versus American caregivers

The study examined differences in motivations for parent care of Korean caregivers and Caucasian American caregivers of elderly parents with dementia. A number of American caregivers, mostly daughters of the demented parents, had affectionate relationships with their parents, but they expressed a relatively low degree of filial responsibility. In contrast, among Korean caregivers, the care of demented parents was predominantly the responsibility of daughters-in-law who were less likely to have affectionate relationships with the parents-in-law. However, Korean caregivers expressed a significantly higher level of filial responsibility than the American caregivers. Some cultural differences between the two ethnic groups associated with parent care were discussed.

Combination of insulin-like growth factor (IGF)-I and IGF-binding protein-1 promotes fibroblast-embedded collagen gel contraction

Wound contraction is an important event that minimizes the wound defect during the healing process. Involvement of insulin-like growth factor (IGF)-I and IGF-binding protein (IGFBP)-1 in wound contraction was studied using an in vitro model. Human dermal fibroblasts (1 x 10(5) cells/ml) were incorporated into a porcine type I collagen (0.21% final) in serum-free medium. The fibroblast-embedded collagen gels in a 12-well plate were floated from the well, and various reagents were then added to the assay medium. The surface area of the gel was calculated by measuring the diameters of the collagen gel. IGF-I at high doses (30 and 100 ng/ml) revealed 6.8% (P < 0.01) and 7.7% (P < 0.001) gel contraction, respectively, and des (1-3) IGF-I at 10 ng/ml produced a 4.5% gel contraction (P < 0.01). Meanwhile, IGFBP-I did not induce any significant contraction throughout the tested concentrations (0.1-100 ng/ml). A combination of IGF-I and IGFBP-1 at 1 ng/ml of each reagent, a concentration at which gel contraction was not observed when each of the reagents was tested individually, produced a 14% gel contraction (P < 0.001), whereas combinations of des (1-3) IGF-I with IGFBP-1 at the same concentrations did not promote gel contraction. The increased IGFBP-I doses in combination with 1 ng/ml IGF-I tended to enhance the gel contraction. IGF-I- and IGFBP-1-induced gel contraction was prominent during the initial 12-h incubation period. When anti-IGF-I, anti-IGFBP-1, or anti-IGF-I receptor antibody was added to the assay medium before the addition of IGF-I and IGFBP-1, the IGF-I- and IGFBP-1-induced gel contraction was significantly suppressed (P < 0.001). Endothelin-1, a vasoconstrictor peptide that is known to promote fibroblast-embedded collagen gel contraction, appeared to be partially involved in the IGF-I- and IGFBP-1-induced gel contraction, because the addition of an endothelin receptor antagonist (Bosentan or BE-18257B at 1 microg/ml) moderately suppressed the IGF-I- and IGFBP-1-induced gel contraction (P < 0.01). On the other hand, when IGF-I and IGFBP-1 were applied with endothelin-1 (1 nM), an enhanced gel contraction (29.4%) was observed that was significantly greater than that induced by either individually (P < 0.001). These results clearly indicate that the combination of IGF-I and IGFBP-1 promotes fibroblast contraction in collagen gel, and that this phenomenon is caused by IGFBP-1's strong potentiation of the IGF-I-induced gel contraction.

Identification of a BglI polymorphism of catechol-O-methyltransferase (COMT) gene, and association study with schizophrenia

Several linkage studies suggested chromosome 22q11-13 may harbor susceptible genes for schizophrenia. Catechol-O-methyl-transferase (COMT), which is involved in the metabolism of catecholamines, was mapped to 22q11 and is considered a possible candidate gene for schizophrenia. Recently, we identified a polymorphic marker, a single nucleotide C insertion at the 3' untranslated region of the COMT gene, which obliterates a BglI site. Using this BglI polymorphism, we conducted a case-control association study in Chinese patients with schizophrenia. No significant differences of allele and genotype frequencies were noted between patients (N = 177) and controls (N = 99). When patients were subgrouped according to sex, no significant differences of genotype and allele frequencies were noted in either male or female patients compared to normal controls. Our results do not support an association between the BglI polymorphism of COMT gene and schizophrenia.

Electrophysiological and electrochemical responses of NMDA in the cerebellum: interactions with nonadrenergic pathway

In the present experiments, we measured N-methyl-D-aspartate (NMDA)-induced norepinephrine (NE) release and extracellular action potentials in the cerebellar cortex of urethane-anesthetized rats. The overflow of NE was measured using a Nafion coated-carbon fiber electrode and in vivo chronoamperometry. We found that both NMDA and quisqualate evoked NE release. Our previous work demonstrated that the electrophysiological activity of cerebellar Purkinje neurons could be either excited or inhibited by local NMDA application. It was reported that bicuculline antagonized NMDA-induced inhibition in Purkinje neurons, suggesting that a GABAergic mechanism was activated during NMDA application. We and others previously found that GABA-mediated electrophysiological depressions were enhanced by NE acting via beta-adrenergic receptors while these responses were decreased by activation of alpha-adrenergic receptors. Since NMDA evokes overflow of endogenous NE, the electrophysiological depression induced by NMDA may contain an NE-mediated modulatory component. In this study, we first examined the interaction of NMDA with beta-adrenergic agonist. We found that local application of isoproterenol facilitated NMDA- or GABA-mediated electrophysiological depressions of the Purkinje neurons. Applications of phenoxybenzamine, which antagonized the alpha-adrenergic response of synaptically released NE, also facilitated NMDA-elicited depression. In contrast, the depression induced by GABA, which did not induce NE overflow, was not potentiated by phenoxybenzamine. The facilitation of NMDA-induced depression by phenoxybenzamine was antagonized by the beta-adrenergic antagonist timolol. Taken together, these data suggested that the nonadrenergic pathway is involved in NMDA-induced electrophysiological responses in the cerebellum. NMDA may induce neuronal depression through modulation of GABAergic inhibition via NMDA-evoked NE release onto cerebellar Purkinje neurons.

A soybean 101-kD heat shock protein complements a yeast HSP104 deletion mutant in acquiring thermotolerance

A cDNA clone encoding a 101-kD heat shock protein (HSP101) of soybean was isolated and sequenced. Genomic DNA gel blot analysis indicated that the corresponding gene is a member of a multigene family. The mRNA for HSP101 was not detected in 2-day-old etiolated soybean seedlings grown at 28 degrees C but was induced by elevated temperatures. DNA sequence comparison has shown that the corresponding gene belongs to the Clp (caseinolytic protease) (or Hsp100) gene family, which is evolutionarily conserved and found in both prokaryotes and eukaryotes. On the basis of the spacer length between the two conserved ATP binding regions, this gene has been identified as a member of the ClpB subfamily. Unlike other Clp genes previously isolated from higher plants, the expression of this soybean Hsp101 gene is heat inducible, and it does not have an N-terminal signal peptide for targeting to chloroplasts. Transformation of the soybean Hsp101 gene into a yeast HSP104 deletion mutant complemented restoration of acquired thermotolerance, a process in which cells survive an otherwise lethal heat stress after they are given a permissive heat treatment.

Changes in the protein components of vitelline envelope during oogenesis of a tubiculous polychaete, Schizobranchia insignis

In sabellid polychaetes the vitelline envelopes, in which microvilli with glycocalyx structures at the tips are invested, change in structure during oogenesis. Vitelline envelopes isolated from Schizobranchia oocytes 25-100 micron and 160-185 micron in diameter, were analyzed in protein components by iodination, electrophoresis, Western blotting and radioactive labeling technique. The observations demonstrate that the membrane proteins of the vitelline envelopes are not consistent but variable in components during oogenesis. Most of these proteins, particularly the high molecular weight proteins, are PAS-positive glycoproteins, which may have specific carbohydrate residues binding to wheat germ agglutinin. The proteins could be labeled with [3H]valine within 36 h by incubating the whole oocytes in sea water to a high level, indicating that the proteins are actively synthesized by the growing oocytes. Synthetic rates of the proteins differ from each other at one stage and are higher in the small than in the large oocytes in general, suggesting that the membrane proteins are involved in the function of the vitelline envelopes during oogenesis.