Abstract P2-09-02: BMN 673 is a PARP inhibitor in clinical development for the treatment of breast cancer patients with deleterious germline BRCA 1 and 2 mutations

Background: BMN 673 is the most potent and specific inhibitor of poly-ADP ribose polymerase (PARP) 1 and 2 in clinical development (IC50<1nM). In BRCA-related tumors, which are genetically dependent on PARP-mediated DNA repair by base excision repair, PARP inhibition induces synthetic lethality. Initial phase 1 results have been presented (de Bono et al JCO 31:5s, 2013 suppl; abstr 2580), showing good tolerability and anti-tumor activity with an MTD on a daily, oral dosing schedule of 1000 μ/day.

Methods: In this 2-stage study, patients with solid tumors including BRCA-related cancers, were enrolled during dose-escalation followed by an expansion phase at the MTD in breast, ovarian, and pancreatic cancer patients with deleterious germline BRCA mutations and in small cell lung cancer and Ewing sarcoma patients to further characterize safety and efficacy. This abstract summarizes demographics and safety for all patients and efficacy for patients with BRCA-related cancers.

Results: As of 17May2013, a total of 1 pancreatic, 18 breast (17F/1M), and 28 ovarian cancer pts with germline BRCA mutations were enrolled at doses from 100-1100 μg/day. All breast cancer patients were treated from 900-1100 μg/day. The median (range) age for all 70 patients is 51.5 (18-81), PS 0 (0-1) and # of prior therapies 4 (1-13), with 47 patients having deleterious BRCA mutations. An MTD of 1000 μg/day was established with thrombocytopenia being dose-limiting. Related adverse events occurring in > 10% of all 70 patients included fatigue, nausea, alopecia, anemia, thrombocytopenia and neutropenia. One patient has had related grade 4 thrombocytopenia. Grade 3 related AE's included fatigue in 1 patient (1%), anemia and thrombocytopenia in 9 each (13%) and neutropenia in 4 (6%). Dose reductions occurred in 11 pts due to myelosuppression. No patients discontinued for adverse events.

Response in Germline BRCA PatientsBRCA Tumor TypeNDose Range (μ/day)ResponseBreast18900-11001CR/6PR/5SD≥12 weeksOvarian28100-11001CR/10PR/19GCIG/4SD≥24 weeksPancreas110001 SD ≥ 12weeksTwo of 2 BRCA breast responders had responded to prior platinum while 0 of 4 non-responders to prior platinum responded to BMN 673. Five of 12 breast cancer pts with no prior platinum have responded.

Conclusions: BMN 673 is well tolerated with impressive anti-tumor activity in pts with deleterious germ line BRCA mutations. Myelosuppression and fatigue are the primary side effects associated with need for dose reduction. A phase 3 trial in metastatic breast cancer patients with deleterious germ line BRCA mutations is planned with single-agent, once-daily oral dosing of 1000 μg (1 mg) per day.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-09-02.

Abstract PD5-3: Anti-metastatic activity, chemotherapeutic enhancement and therapeutic potential of targeting Hsp90 with ganetespib in triple negative breast cancer

Background: While the incidence of triple negative breast cancer (TNBC) is only 10-20%, these tumors show a disproportionate mortality for breast cancer patients. Due to a lack of effective molecular targets in this disease, therapeutic options are largely limited to systemic chemotherapeutic approaches which have shown disappointing efficacy in the metastatic setting. Here we undertook a comprehensive evaluation of the activity of the drug candidate, ganetespib, a potent inhibitor of heat shock protein 90 (Hsp90), in this malignancy.

Methods: The sensitivity of TNBC cells to ganetespib was determined in viability assays using a panel of tumor lines. The effects of ganetespib exposure on client proteins and their effector pathways were examined by Western blot and reverse phase protein array analysis. The anti-metastatic activity of ganetespib was evaluated using a 4T1 metastasis model. Combinatorial drug analyses were performed with chemotherapeutic agents. DNA damage and cell cycle disruption were assessed using the comet assay, Western blotting and fluorescence microscopy. The in vivo efficacy of the compound, both as a single agent and in combination, was established using MDA-MB-231 xenograft models. Computed tomography scans were obtained for a metastatic TNBC patient undergoing ganetespib treatment.

Results: Ganetespib reduced cell viability in TNBC cell lines with low nanomolar potency. Ganetespib treatment induced robust destabilization of multiple client proteins and oncogenic signaling pathways and suppressed lung metastasis in the experimental model. Ganetespib potentiated the cytotoxic activity of doxorubicin via enhanced DNA damage and mitotic arrest, conferring superior efficacy to the doxorubicin + cyclophosphamide (AC) regimen in MDA-MB-231 xenograft models. Ganetespib also promoted mitotic catastrophe and apoptosis in combination with taxanes in vitro, and these effects translated to significantly improved combinatorial activity in vivo. Marked tumor shrinkage of metastatic lung lesions was seen in the patient while on ganetespib monotherapy.

Conclusion: The preclinical activity profile and clinical evidence of tumor regression suggest that ganetespib offers considerable promise as a new therapeutic candidate to target TNBC. In particular, the capacity of ganetespib to potentiate the activity of standard of care chemotherapeutics provides a rationale for the exploration of this agent in novel combinatorial treatment strategies for this disease.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD5-3.

Observation of a charged charmoniumlike structure Zc(4020) and search for the Zc(3900) in e+e-→π+π-hc

We study e+e-→π+π-hc at center-of-mass energies from 3.90 to 4.42 GeV by using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross sections are measured at 13 energies and are found to be of the same order of magnitude as those of e+e-→π+π-J/ψ but with a different line shape. In the π±hc mass spectrum, a distinct structure, referred to as Zc(4020), is observed at 4.02  GeV/c2. The Zc(4020) carries an electric charge and couples to charmonium. A fit to the π±hc invariant mass spectrum, neglecting possible interferences, results in a mass of (4022.9±0.8±2.7)  MeV/c2 and a width of (7.9±2.7±2.6)  MeV for the Zc(4020), where the first errors are statistical and the second systematic. The difference between the parameters of this structure and the Zc(4025) observed in the D*D[over ¯]* final state is within 1.5σ, but whether they are the same state needs further investigation. No significant Zc(3900) signal is observed, and upper limits on the Zc(3900) production cross sections in π±hc at center-of-mass energies of 4.23 and 4.26 GeV are set.

An in vivo study of hindfoot 3D kinetics in stage II posterior tibial tendon dysfunction (PTTD) flatfoot based on weight-bearing CT scan

OBJECTIVE

The objective of this study was to evaluate the rotation and translation of each joint in the hindfoot and compare the load response in healthy feet with that in stage II posterior tibial tendon dysfunction (PTTD) flatfoot by analysing the reconstructive three-dimensional (3D) computed tomography (CT) image data during simulated weight-bearing.

METHODS

CT scans of 15 healthy feet and 15 feet with stage II PTTD flatfoot were taken first in a non-weight-bearing condition, followed by a simulated full-body weight-bearing condition. The images of the hindfoot bones were reconstructed into 3D models. The 'twice registration' method in three planes was used to calculate the position of the talus relative to the calcaneus in the talocalcaneal joint, the navicular relative to the talus in talonavicular joint, and the cuboid relative to the calcaneus in the calcaneocuboid joint.

RESULTS

From non- to full-body-weight-bearing condition, the difference in the talus position relative to the calcaneus in the talocalcaneal joint was 0.6° more dorsiflexed (p = 0.032), 1.4° more everted (p = 0.026), 0.9 mm more anterior (p = 0.031) and 1.0 mm more proximal (p = 0.004) in stage II PTTD flatfoot compared with that in a healthy foot. The navicular position difference relative to the talus in the talonavicular joint was 3° more everted (p = 0.012), 1.3 mm more lateral (p = 0.024), 0.8 mm more anterior (p = 0.037) and 2.1 mm more proximal (p = 0.017). The cuboid position difference relative to the calcaneus in the calcaneocuboid joint did not change significantly in rotation and translation (all p ≥ 0.08).

CONCLUSION

Referring to a previous study regarding both the cadaveric foot and the live foot, joint instability occurred in the hindfoot in simulated weight-bearing condition in patients with stage II PTTD flatfoot. The method used in this study might be applied to clinical analysis of the aetiology and evolution of PTTD flatfoot, and may inform biomechanical analyses of the effects of foot surgery in the future. Cite this article: Bone Joint Res 2013;2:255-63.

ROCK has a crucial role in regulating prostate tumor growth through interaction with c-Myc

Rho-associated kinase (ROCK) has an essential role in governing cell morphology and motility, and increased ROCK activity contributes to cancer cell invasion and metastasis. Burgeoning data suggest that ROCK is also involved in the growth regulation of tumor cells. However, thus far, the molecular mechanisms responsible for ROCK-governed tumor cell growth have not been clearly elucidated. Here we showed that inhibition of ROCK kinase activity, either by a selective ROCK inhibitor Y27632 or by specific ROCK small interfering RNA (siRNA) molecules, attenuated not only motility but also the proliferation of PC3 prostate cancer cells in vitro and in vivo. Importantly, mechanistic investigation revealed that ROCK endowed cancer cells with tumorigenic capability, mainly by targeting c-Myc. ROCK could increase the transcriptional activity of c-Myc by promoting c-Myc protein stability, and ROCK inhibition reduced c-Myc-mediated expression of mRNA targets (such as HSPC111) and microRNA targets (such as miR-17-92 cluster). We provided evidence demonstrating that ROCK1 directly interacted with and phosphorylated c-Myc, resulting in stabilization of the protein and activation of its transcriptional activity. Suppression of ROCK-c-Myc downstream molecules, such as c-Myc-regulated miR-17, also impaired tumor cell growth in vitro and in vivo. In addition, c-Myc was shown to exert a positive feedback regulation on ROCK by increasing RhoA mRNA expression. Therefore, inhibition of ROCK and its stimulated signaling might prove to be a promising strategy for restraining tumor progression in prostate cancer.

Synergistic function of Kras mutation and HBx in initiation and progression of hepatocellular carcinoma in mice

Although the activation of Ras pathway is frequently observed in human hepatocellular carcinoma (HCC), the in vivo role of Ras activation in HCC initiation and progression is underdetermined. To test the consequence of Kras activation in hepatocyte, we generated a hepatocyte-specific Kras(G12D) transgenic mouse strain and observed spontaneous development of HCC in these mice. Remarkably, HBV X protein (HBx) expression significantly promotes the formation and malignant progression of Kras(G12D)-driven HCC as shown with the accelerated tumor onset, the increased tumor burden and the more poorly differentiated lesions. At the cellular level, concomitant expression of Kras(G12D) and HBx results in a robust increase in hepatocellular proliferation. We reveal that the Akt, MAPK, p53 and TGF-β pathways are deregulated in the Kras(G12D)-driven HCCs. Also, the dysregulation is more pronounced in the HCCs developed in Kras(G12D) and HBx double transgenic mice. In addition, the altered expressions of β-catenin, CD44 and E-cadherin are only observed in the Kras(G12D) and HBx double transgenic mice. These results demonstrate a crucial role of Ras activation in hepatocellular carcinogenesis and the functional synergy between Kras(G12D) and HBx in HCC initiation and progression. The novel genetic mouse models that closely recapitulate the histopathologic progression and molecular alterations of human HCC may potentially facilitate the future therapeutic studies.

Expression of STAT3 and IGF2 in adrenocortical carcinoma and its relationship with angiogenesis

OBJECTIVE

The aim of this study was to determine the correlation between human adrenocortical carcinoma and the proteins involved in tumor angiogenesis, and to evaluate the angiogenic status of adrenocortical carcinoma.

METHODS

The expression of signal transducer and activator of transcription 3 and insulin-like growth factor 2 as well as microvessel density was measured in a series of tissue samples from 44 human sporadic adrenocortical tumors by immunohistochemistry. These specimens were classified as adenomas (n = 20) and carcinomas (n = 24) according to the histological criteria defined by Weiss.

RESULTS

A total of 19 of 24 (79.17 %) malignant cases showed positive staining for signal transducer and activator of transcription 3 and 4 of 20 (20.00 %) benign cases showed positive, the difference of signal transducer and activator of transcription 3 expression between adrenocortical adenomas and adrenocortical carcinomas was statistically significant (P < 0.001). Similarly, insulin-like growth factor 2 staining was seen in 70.83 % (17/24) of the malignant cases versus 25.00 % (5/20) of the benign, the difference of insulin-like growth factor 2 expression among two groups was statistically significant (P = 0.002). Malignant cases showed higher microvessel density compared to benign tumors (84.70 ± 12.44 vs 21.05 ± 8.07, P < 0.001). Signal transducer and activator of transcription 3 and insulin-like growth factor 2 expression were positively correlated with microvessel density in all specimens (r_s = 0.832, P < 0.001; r_s = 0.703, P = 0.001).

CONCLUSIONS

This study has confirmed that adrenocortical carcinoma overexpress signal transducer and activator of transcription 3 and insulin-like growth factor 2; these results suggest that angiogenesis of human adrenocortical carcinoma may be mediated by these proteins and they could represent selective targets for the molecularly targeted treatments of adrenocortical carcinoma.

Leptin levels in patients with psoriasis: a meta-analysis

BACKGROUND

There have been inconsistent results reported for leptin levels in patients with psoriasis.

AIM

To evaluate leptin levels in patients with psoriasis using a meta-analysis of studies comparing leptin levels in controls and in patients with psoriasis.

METHODS

PubMed (MEDLINE), EMBASE and the Cochrane Library were searched for relevant papers published in English. Pooled weighted mean differences (WMDs) and 95% CIs were calculated using random-effects and fixed-effects models. Heterogeneity between studies was assessed using the Cochran Q and I(2) statistics.

RESULTS

In total, 11 studies, comprising 773 patients with psoriasis and 570 healthy controls, were identified. Leptin levels were significantly higher in patients with psoriasis compared with controls (WMD = 7.24, 95% CI 4.55-9.93; P < 0.001). On stratified analysis, significant differences in leptin levels between patients with psoriasis and controls were reported only in serum samples (P < 0.001), and not in plasma samples (P = 0.025). Sensitivity analysis showed that there were no changes in the direction of effect when any one study was excluded. No publication bias was detected.

CONCLUSIONS

Leptin levels are higher in patients with psoriasis compared with those in controls. Future studies are warranted to clarify the association between leptin levels and the pathomechanism of psoriasis.

Facile synthesis of graphene on dielectric surfaces using a two-temperature reactor CVD system

Direct deposition of graphene on a dielectric substrate is demonstrated using a chemical vapor deposition system with a two-temperature reactor. The two-temperature reactor is utilized to offer sufficient, well-proportioned floating Cu atoms and to provide a temperature gradient for facile synthesis of graphene on dielectric surfaces. The evaporated Cu atoms catalyze the reaction in the presented method. C atoms and Cu atoms respectively act as the nuclei for forming graphene film in the low-temperature zone and the zones close to the high-temperature zones. A uniform and high-quality graphene film is formed in an atmosphere of sufficient and well-proportioned floating Cu atoms. Raman spectroscopy, scanning electron microscopy and atomic force microscopy confirm the presence of uniform and high-quality graphene.

Prenatal ethanol exposure has sex-specific effects on hippocampal long-term potentiation

Alcohol consumption during pregnancy is deleterious to the developing brain of the fetus and leads to persistent deficits in adulthood. Long-term potentiation (LTP) is a biological model for learning and memory processes and previous evidence has shown that prenatal ethanol exposure (PNEE) affects LTP in a sex specific manner during adolescence. The objective of this study was to determine if there are sex specific differences in adult animals and to elucidate the underlying molecular mechanisms that contribute to these differences. Pregnant Sprague-Dawley dams were assigned to either; liquid ethanol, pair-fed or standard chow diet. In vivo electrophysiology was performed in the hippocampal dentate gyrus (DG) of adult offspring. LTP was induced by administering 400 Hz stimuli. Western blot analysis for glutamine synthetase (GS) and glutamate decarboxylase from tissue of the DG indicated that GS expression was increased following PNEE. Surprisingly, adult females did not show any deficit in N-methyl-D-aspartate (NMDA)-dependent LTP after PNEE. In contrast, males showed a 40% reduction in LTP. It was indicated that glutamine synthetase expression was increased in PNEE females, suggesting that altered excitatory neurotransmitter replenishment may serve as a compensatory mechanism. Ovariectomizing females did not influence LTP in control or PNEE animals, suggesting that circulating estradiol levels do not play a major role in maintaining LTP levels in PNEE females. These results demonstrate the sexually dimorphic effects of PNEE on the ability for the adult brain to elicit LTP in the DG. The mechanisms for these effects are not fully understood, but an increase in glutamine synthetase in females may underlie this phenomenon.

Long distance directional growth of dopaminergic axons along pathways of netrin-1 and GDNF

Different experimental and clinical strategies have been used to promote survival of transplanted embryonic ventral mesencephalic (VM) neurons. However, few studies have focused on the long-distance growth of dopaminergic axons from VM transplants. The aim of this study is to identify some of the growth and guidance factors that support directed long-distance growth of dopaminergic axons from VM transplants. Lentivirus encoding either glial cell line-derived neurotrophic factor (GDNF) or netrin-1, or a combination of lenti-GDNF with either lenti-GDNF family receptor α1 (GFRα-1) or lenti-netrin-1 was injected to form a gradient along the corpus callosum. Two weeks later, a piece of embryonic day 14 VM tissue was transplanted into the corpus callosum adjacent to the low end of the gradient. Results showed that tyrosine hydroxylase (TH(+)) axons grew a very short distance from the VM transplants in control groups, with few axons reaching the midline. In GDNF or netrin-1 expressing groups, more TH(+) axons grew out of transplants and reached the midline. Pathways co-expressing GDNF with either GFRα-1 or netrin-1 showed significantly increased axonal outgrowth. Interestingly, only the GDNF/netrin-1 combination resulted in the majority of axons reaching the distal target (80%), whereas along the GDNF/GFRα-1 pathway only 20% of the axons leaving the transplant reached the distal target. This technique of long-distance axon guidance may prove to be a useful strategy in reconstructing damaged neuronal circuits, such as the nigrostriatal pathway in Parkinson's disease.

Genetic variants of the genes encoding zinc finger protein 313 and interleukin-13 confer a risk for psoriasis in a Chinese Uygur population

BACKGROUND

Recent work using genome–wide association studies (GWAS) in Chinese Han and white populations have discovered several novel psoriasis susceptibility genes.

AIM

To examine whether the risk loci for psoriasis identified in previous GWAS in a white population are also associated with psoriasis in a Chinese Uygur population in Xinjiang.

METHODS

Genotyping analysis of eight single-nucleotide polymorphisms (SNPs) associated with psoriasis was performed for 539 patients with psoriasis and 749 controls, all of Chinese Uygur descent, using a commercial assay.

RESULTS

Two SNPs had an association with psoriasis in this Chinese Uygur population: SNP rs495337 in the gene encoding for zinc finger protein 313 (P < 0.001; OR = 0.80) and SNP rs20541 of the gene encoding for interleukin-13 (P < 0.001; OR = 0.82). In subgroup analyses, the two SNPs were significantly associated (P < 0.05) with type I psoriasis, Rs495337 showed statistically difference between positive family history of psoriasis patients and controls whereas rs20541 might preferentially associated with negative family history psoriasis patients. Interestingly, using multifactor dimensionality reduction, a significant two-locus interaction was seen between rs495337 and rs20541, with a crossvalidation consistency of 4/5 and average balanced prediction (accuracy 55.5%, P < 0.001).

CONCLUSIONS

ZNF313 and IL-13 are associated with risk for psoriasis in a Chinese Uygur population, and there is an effect of interaction between the two genes on this risk.

Clinical analysis of the characterization of magnetic resonance imaging in 102 cases of refractory haematospermia

To analyze the pathogenesis of persistent and refractory haematospermia and to evaluate the aetiological diagnostic value of magnetic resonance imaging (MRI) for this type of haematospermia. Clinical data from 102 patients with persistent and refractory haematospermia was retrospectively analysed. Data collected included history, symptoms, as well as ultrasound and MRI of the morphological features of the bilateral seminal vesicles (SV) and ejaculatory duct (ED) areas. Criteria for inclusion were haematospermia symptoms that occurred more than six times, that lasted more than 6 months, and that did not improve after >1 month of conservative treatment. Patients underwent seminal vesiculoscopy with a post-surgery follow-up of 3-48 months [average (18.1 ± 10.3) months]. Of the 102 patients that underwent MRI examination, data from 88 patients (86.3%) showed typical and characteristic changes in the ED area, including the signal intensity changes in 60 (58.8%), SV volume changes in 32(31.4%), the formation of cysts such as prostatic utricular cysts in 27 (26.5%), Müllerian cysts in 4 (3.9%), ED cysts in 5 (4.9%) and a SV cyst in 1(1.0%). The MRI findings were confirmed by seminal vesiculoscopy and all patients received appropriate treatment. In 14 patients (13.7%), no obvious abnormal changes were observed with MRIs, however, these patients were diagnosed and successfully managed using seminal vesiculoscopy. Some degrees of ED obstruction was usually found during surgery. The symptoms of haematospermia disappeared 1-2 months after surgery in all patients. Two patients had a recurrence of haematospermia, underwent the same treatment, and recovered during the follow-up period. The aetiology of the most cases of the refractory haematospermia can be distinguished using the three-dimensional MRI. Typical abnormalities observed on MR images are signal intensity, SV volume changes and cyst formation. MRI has significant etiological diagnostic value and provides reliable information for the subsequent treatment of patients with persistent and refractory haematospermia.

Atorvastatin overcomes gefitinib resistance in KRAS mutant human non-small cell lung carcinoma cells

The exact influence of statins on gefitinib resistance in human non-small cell lung cancer (NSCLC) cells with KRAS mutation alone or KRAS/PIK3CA and KRAS/PTEN comutations remains unclear. This work found that transfection of mutant KRAS plasmids significantly suppressed the gefitinib cytotoxicity in Calu3 cells (wild-type KRAS). Gefitinib disrupted the Kras/PI3K and Kras/Raf complexes in Calu3 cells, whereas not in Calu3 KRAS mutant cells. These trends were corresponding to the expression of pAKT and pERK in gefitinib treatment. Atorvastatin (1 μM) plus gefitinib treatment inhibited proliferation, promoted cell apoptosis, and reduced the AKT activity in KRAS mutant NSCLC cells compared with gefitinib alone. Atorvastatin (5 μM) further enhanced the gefitinib cytotoxicity through concomitant inhibition of AKT and ERK activity. Atorvastatin could interrupt Kras/PI3K and Kras/Raf complexes, leading to suppression of AKT and ERK activity. Similar results were also obtained in comutant KRAS/PTEN or KRAS/PIK3CA NSCLC cells. Furthermore, mevalonate administration reversed the effects of atorvastatin on the Kras/Raf and Kras/PI3K complexes, as well as AKT and ERK activity in both A549 and Calu1 cells. The in vivo results were similar to those obtained in vitro. Therefore, mutant KRAS-mediated gefitinib insensitivity is mainly derived from failure to disrupt the Kras/Raf and Kras/PI3K complexes in KRAS mutant NSCLC cells. Atorvastatin overcomes gefitinib resistance in KRAS mutant NSCLC cells irrespective of PIK3CA and PTEN statuses through inhibition of HMG-CoA reductase-dependent disruption of the Kras/Raf and Kras/PI3K complexes.

Hesperidin pretreatment protects hypoxia-ischemic brain injury in neonatal rat

Neonatal hypoxia-ischemic encephalopathy (HIE) remains a major cause of brain damage, leading to high disability and mortality rates in neonates. In vitro studies have shown that hesperidin, a flavanone glycoside found abundantly in citrus fruits, acts as an antioxidant. Although hesperidin has been considered as a potential treatment for HIE, its effects have not been fully evaluated. In this study, the protective effect of hesperidin pretreatment against hypoxia-ischemic (HI) brain injury and possible signal pathways were investigated using in vivo and in vitro models. In vivo HI model employed unilateral carotid ligation in postnatal day 7 rat with exposure to 8% hypoxia for 2.5h, whereas in vitro model employed primary cortical neurons of neonatal rats subjected to oxygen and glucose deprivation for 2.5h. Hesperidin pretreatment significantly reduced HI-induced brain tissue loss and improved neurological outcomes as shown in 2,3,5-triphenyltetrazolium chloride monohydrate staining and foot-fault results. The neuroprotective effects of hesperidin are likely the results of preventing an increase in intracellular reactive oxygen species and lipid peroxide levels. Hesperidin treatment also activated a key survival signaling kinase, Akt, and suppressed the P-FoxO3 level. Hesperidin pretreatment protected neonatal HIE by reducing free radicals and activating phosphorylated Akt.

First Report of Phytophthora palmivora Causing Fruit Rot of Fig (Ficus carica L.) in China

Fresh fig (Ficus carica L.) has been grown on a large scale in Beijing, China, since 2011. In late July 2012, a rot disease occurred on immature fruit of fig after a heavy rain (average daily rainfall 170 mm) in Fangshan District, Beijing, which caused about 30% incidence of green fruit on trees. The symptom first appeared as a water-soaked lesion that was covered with a white, fluffy mass of mycelia, followed by a soft, mushy rot of infected area on the fruit. To isolate the causal agent, mycelia and sporangia from 10 symptomatic fruits were suspended in sterile water, spread on potato dextrose agar (PDA) plates, and incubated at 25°C for 18 h. The isolates from each diseased fruit showed the same colonial characteristics. A single sporangium was isolated under a dissecting microscope and transferred onto PDA to obtain a pure culture. On carrot agar, the colony was white and homogeneous with tidy edge, with a few aerial hyphae. Sporangia were obpyriform with obvious papillae and measured 54.7 to 63.8 (59.3) × 26.5 to 36.3 (30.7) μm. The chlamydospores produced in culture were spherical. The pathogen was identified as Phytophthora palmivora based on the morphological characteristics (3) and confirmed with ITS sequences by PCR amplification using rDNA universal primers ITS1 and ITS4. The resulting sequence (Accession No. KC131229) had a 99% identity to that of P. palmivora (JQ354937) isolated from Pachira aquatica. Koch's postulates were conducted by inoculating six surface-sterilized figs with a PDA plug from a 7-day-old culture, with six noninoculated (PDA plugs only) fruits serving as controls. The inoculated fruits were incubated at room temperature in a plastic box covered with film. Symptoms similar to those on the naturally infected fruits began on wounded fruits 48 h after inoculation and on non-wounded fruits 60 h after inoculation, while the six control fruits remained healthy. P. palmivora was reisolated from the symptomatic fruit tissue. P. palmivora is one of the most severe pathogens on edible figs, being reported by Japanese in 1941 (2). Fruit rot of fig caused by the pathogen was reported in Florida in 1984 (1). To our knowledge, this is the first report of P. palmivora leading to fruit rot on fig in China. References: (1) N. E. El-Gholl and S. A. Alfieri, Jr. Proc. Fla. State Hort. Soc. 97:327, 1984. (2) Y. Nisikado et al. Ber. Ohara Inst. 8:427, 1941. (3) Y. N. Yu. Flora Fungorum Sinicorum: Peronosporales (in Chinese) Vol. 6. Science Press, Beijing, 1998.

Blood pressure reducing effects of piromelatine and melatonin in spontaneously hypertensive rats

BACKGROUND

Recently, widespread interest has grown regarding melatonin treatment of hypertension including its cardioprotective effects. Studies in rodents indicate that melatonin plays a role in the pathogenesis of hypertension in rats with metabolic syndrome. Piromelatine, a melatonin agonist, serotonin 5-HT-1A and 5-HT-1D agonist and serotonin 5-HT2B antagonist is a multimodal agent with sleep promoting, anti-diabetic, analgesic, anti-neurodegenerative, anxiolytic and antidepressant potential, currently in development for the treatment of insomnia.

AIM

In this report we assessed the effects of piromelatine and melatonin treatment on blood pressure in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats.

MATERIALS AND METHODS

Five groups of 12-wk-old rats (10/group) were treated for 5 weeks with a vehicle, piromelatine (5, 15 and 50 mg/kg BW) and melatonin (10 mg/kg BW) and an age-matched WKY control group. Systolic blood pressure (tail-cuff method) was measured weekly at 9:00 a.m. and at 9:00 p.m. The rats body weight, plasma glucose, insulin, triglyceride, adiponectin, total cholesterol, HDL and LDL/VLDL cholesterol were also measured.

RESULTS

Our results showed that both piromelatine and melatonin reduced SHR blood pressure significantly both during the morning and the evening. Piromelatine, but not melatonin, also reduced SHR body weight gain and both significantly decreased plasma glucose and insulin levels and increased adiponectin levels.

CONCLUSIONS

Piromelatine, similar to melatonin, has an antihypertensive effect and also attenuates body weight, improves metabolic profiles and might be useful in the treatment of hypertension and the metabolic syndrome.

Controllable transition of silk fibroin nanostructures: an insight into in vitro silk self-assembly process

Silk fiber is one of the strongest and toughest biological materials with hierarchical structures, where nanofibril with size <20nm is a critical factor in determining its excellent mechanical properties. Although silk nanofibrils have been found in natural and regenerated silk solutions, there is no way to actively control nanofibril formation in aqueous solution. This study shows a simple but effective method of preparing silk nanofibrils by regulating the silk self-assembly process. Through a repeated drying-dissolving process, a silk fibroin solution composed of metastable nanoparticles was first prepared and then used to reassemble nanofibrils with different sizes and secondary conformations under various temperatures and concentrations. These nanofibrils have a similar size to that of natural fibers, providing a suitable unit to further assemble the hierarchical structure in vitro. Several important issues, such as the relationships between silk nanofibrils, secondary conformations and viscosity, are also investigated, giving a new insight into the self-assembly process. In summary, besides rebuilding silk nanofibrils in aqueous solution, this study provides an important model for furthering the understanding of silk structures, properties and forming mechanisms, making it possible to regenerate silk materials with exceptional properties in the future.