A recruiting protein of geranylgeranyl diphosphate synthase controls metabolic flux toward chlorophyll biosynthesis in rice.

In plants, geranylgeranyl diphosphate (GGPP) is produced by plastidic GGPP synthase (GGPPS) and serves as a precursor for vital metabolic branches, including chlorophyll, carotenoid, and gibberellin biosynthesis. However, molecular mechanisms regulating GGPP allocation among these biosynthetic pathways localized in the same subcellular compartment are largely unknown. We found that rice contains only one functionally active GGPPS, OsGGPPS1, in chloroplasts. A functionally active homodimeric enzyme composed of two OsGGPPS1 subunits is located in the stroma. In thylakoid membranes, however, the GGPPS activity resides in a heterodimeric enzyme composed of one OsGGPPS1 subunit and GGPPS recruiting protein (OsGRP). OsGRP is structurally most similar to members of the geranyl diphosphate synthase small subunit type II subfamily. In contrast to members of this subfamily, OsGRP enhances OsGGPPS1 catalytic efficiency and specificity of GGPP production on interaction with OsGGPPS1. Structural biology and protein interaction analyses demonstrate that affinity between OsGRP and OsGGPPS1 is stronger than between two OsGGPPS1 molecules in homodimers. OsGRP determines OsGGPPS1 suborganellar localization and directs it to a large protein complex in thylakoid membranes, consisting of geranylgeranyl reductase (OsGGR), light-harvesting-like protein 3 (OsLIL3), protochlorophyllide oxidoreductase (OsPORB), and chlorophyll synthase (OsCHLG). Taken together, genetic and biochemical analyses suggest OsGRP functions in recruiting OsGGPPS1 from the stroma toward thylakoid membranes, thus providing a mechanism to control GGPP flux toward chlorophyll biosynthesis.

Oxido[N-(2-oxidobenzyl-idene-κO)leucinato-κ²N,O](1,10-phenanthroline-κ²N,N')vanadium(IV).

In the title V(IV) complex, [VO(C13H15NO3)(C12H8N2)], the oxidovanadium cation is N,N'-chelated by a 1-10-phenanthroline ligand and N,O,O'-chelated by a Schiff base anion in a distorted octa-hedral geometry. Weak inter-molecular C-H⋯O hydrogen bonds occur in the crystal structure which contains solvent-accessible voids of 81 ų.

Solitary plasmacytoma of the left rib misdiagnosed as angina pectoris: A case report.

BACKGROUND: Solitary plasmacytoma in the left rib is rare and can cause chest discomfort such as chest pain and tightness, and its clinical manifestations are not typical, so it is often misdiagnosed. We report a case of left costal plasmacytoma misdiagnosed as angina pectoris. We also review the literature and provide suggestions as to how to avoid misdiagnosis. CASE SUMMARY: A 77-year-old man with a history of intermittent chest tightness for 3 years presented with pain in the left chest for 1 wk and was admitted to hospital. The cardiologists initially diagnosed angina pectoris but the findings of coronary angiography were not consistent with the symptoms. Computed tomography showed that the left eighth rib mass was accompanied by bone destruction. The patient was transferred to our department for further treatment. Preoperative biopsy indicated that the lesion was possibly malignant, and elective surgery was performed to remove the lesion. The size of the tumor was about 4 cm. The tumor was spindle-shaped and protruded into the pleural cavity, without invading the lungs. Postoperative pathology confirmed that the left rib lesion was plasmacytoma. After 14 mo follow-up, the patient died of systemic metastasis. CONCLUSION: Left rib solitary plasmacytoma is a rare disease confined to a specific rib and can cause local pain. Attention should be paid to the differential diagnosis of angina pectoris to avoid misdiagnosis.

Interrelationship of Gut Microbiota, Obesity, Body Composition and Insulin Resistance in Asians with Type 2 Diabetes Mellitus.

Metabolic syndrome (MS) has been an important health issue in the world, and insulin resistance (IR) is one of the characteristics of MS, increasing the risk for the onset and poor prognosis of type 2 diabetes mellitus (T2D). However, the interactional effect of obesity or abnormal body composition on the correlation between gut microbiota and IR in T2D patients is not well-explored. This cross-sectional study used a body composition monitor to evaluate lean tissue mass and fat tissue mass. IR was calculated using homeostatic model assessment-insulin resistance (HOMA-IR). Eight pairs of 16S rRNA gene primers specific to Firmicutes, Bacteroidetes, Clostridium leptum group, Faecalibacteriumprausnitzii, B acteroides, Bifidobacterium, Akkermansia muciniphila, and Escherichia coli were utilized to measure their abundance by qPCR. One hundred and fifty-four T2D patients were enrolled and stratified by the median HOMA-IR (2.5) and body mass index (BMI) of 25 kg/m2. A lower abundance of A. muciniphila was found in T2D patients with high HOMA-IR and BMI respectively. HOMA-IR and BMI had a synergistic effect on the reduction of the abundance of A. muciniphila. After adjusting metabolic factors, the low abundance of A. muciniphila significantly increased the risk for greater severity of IR. Furthermore, the negative correlation between A. muciniphila and IR was only found in T2D patients with high lean tissue. In conclusion, decreased abundance of fecal A. muciniphila enhanced the severity of IR in Asians with T2D, especially those having lean mass, and this significant relationship was independent of obesity.

[Study on intra-gastric floating beads of naringenin].

OBJECTIVE: To prepare calcium alginate-chitosan intra-gastric floating beads of naringenin combining with the solid dispersion method and investigate the in vitro floating characteristics, entrapment efficiency and drug release property of the beads. METHODS: The solid dispersion of naringenin was prepared by the Eudragit RLPO. Sodium alginate solution mixed with the powder of the solid dispersion of naringenin and frother was slowly dripped into chitosan-calcium chloride solution added with acetic acid. Calcium alginatechitosan intra-gastric floating beads of naringenin were obtained after drying. The effects of solid dispersion on in vitro release of naringenin were investigated. RESULTS: Intra-gastric floating beads of naringenin were acquired successfully. More than 70% of the beads kept floating in artificial gastric juice in 9 h, the release ratio of naringenin during 9 h was 65%-70% and the entrapment efficiency was about 70%-80%. CONCLUSION: The sustained release of naringenin in the calcium alginate-chitosan intra-gastric floating beads could be achieved by using the solid dispersion method and it provides some ideas of intra-gastric floating preparations.

Z-ligustilide attenuates lipopolysaccharide-induced proinflammatory response via inhibiting NF-kappaB pathway in primary rat microglia.

AIM: To investigate the anti-inflammatory effect of Z-ligustilide (LIG) on lipopolysaccharide (LPS)-activated primary rat microglia. METHODS: Microglia were pretreated with LIG 1 h prior to stimulation with LPS (1 microg/mL). After 24 h, cell viability was tested with MTT, nitric oxide (NO) production was assayed with Griess reagent, and the content of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and monocyte chemoattractant protein (MCP-1) was measured with ELISA. Protein expression of the nuclear factor-kappaB (NF-kappaB) p65 subunit, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) was detected with immunocytochemistry 1 h or 24 h after LPS treatment. RESULTS: LIG showed a concentration-dependent anti-inflammatory effect in LPS-activated microglia, without causing cytotoxicity. Pretreatment with LIG at 2.5, 5, 10, and 20 micromol/L decreased LPS-induced NO production to 75.9%, 54.4%, 43.1%, and 47.6% (P<0.05 or P< 0.01), TNF-alpha content to 86.2%, 68.3%, 40.1%, and 39.9% (P<0.01, with the exception of 86.2% for 2.5 micromol/L LIG), IL-1beta content to 31.5%, 27.7%, 0.6%, and 0% (P<0.01), and MCP-1 content to 84.4%, 50.3%, 45.1%, and 42.2% (P<0.05 or P<0.01), respectively, compared with LPS treatment alone. LIG (10 micromol/L) significantly inhibited LPS-stimulated immunoreactivity of activated NF-kappaB, COX-2, and iNOS (P<0.01 vs LPS group). CONCLUSION: LIG exerted a potent anti-inflammatory effect on microglia through inhibition of NF-kappaB pathway. The data provide direct evidence of the neuroprotective effects of LIG and the potential application of LIG for the treatment of the neuroinflammatory diseases characterized by excessive microglial activation.

Quantitative MR phase-corrected imaging to investigate increased brain iron deposition of patients with Alzheimer disease.

PURPOSE: Brain iron deposition has been proposed to play an important role in the pathophysiology of neurodegenerative diseases. The aim of this study was to investigate the correlation of brain iron accumulation with the severity of cognitive impairment in patients with Alzheimer disease (AD). MATERIALS AND METHODS: This study was approved by the institutional review board of Tongji Hospital (Wuhan, China) and written informed consent was obtained from all participants. Fifteen patients with AD, 15 age-and sex-matched healthy controls, and 30 healthy volunteers underwent high-resolution magnetic resonance (MR) phase-corrected imaging. The phase shift and iron concentrations of the bilateral hippocampus (HP), parietal cortex (PC), frontal white matter, putamen (PU), caudate nucleus (CN), thalamus, red nucleus, substantia nigra, and dentate nucleus (DN) of the cerebellum were examined for correlation with severity of dementia by using a two-tailed Student-Newman-Keuls t test (analysis of variance) and linear correlation test. RESULTS: Regional phase shifts on phase-corrected images were negatively correlated with regional brain iron concentration in healthy adults (r = -0.926, P = .003). Iron concentrations in the bilateral HP, PC, PU, CN, and DN subregions of patients with AD were significantly higher than the controls (P < .05), Moreover, these brain iron concentrations, especially those in the PC at the early stages of AD, were positively correlated with the severity of patients' cognitive impairment (P < .05). CONCLUSION: Iron concentration in the PC was positively correlated with the severity of AD patients' cognitive impairment, indicating that it may be used as a biomarker to evaluate the progression of AD.

[Pharmacological activities of Z-ligustilide and metabolites in rats].

OBJECTIVE: To study the metabolism of Z-ligustilide(Z-LIG) in vivo and in vitro in rats and the pharmacological activities of Z-LIG and metabolites in vitro. METHODS: The biotransformation of Z-LIG in rats in vivo was tested. Z-LIG was also incubated with rat liver microsomes in vitro. The incubated product was extracted, separated and identified with high performance liquid chromatography (HPLC), high resolution mass spectrometry, nuclear magnetic resonance spectrum and UV. The effects of Z-LIG and its main metabolites on hydrogen peroxide (H1O2)-induced injuries were examined in cultured PC12 cells. RESULTS: The HPLC analysis of the metabolites of Z-LIG was obtained. Senkyunolide I (SYL) isolated from in vitro incubation was identified as the main metabolite of Z-LIG. Both Z-LIG and SYL showed significant and concentration-dependent protection against H2O2-induced injuries in PC12 cells. CONCLUSION: SYL is the main metabolite of Z-LIG in rats. Z-LIG and SYL exert similar protective effects against oxidative damage in cultured PC12 cells.

[Study on absorption mechanism of puerarin and its nanoparticles across Caco-2 cell model].

OBJECTIVE: To study the absorption mechanism of puerarin and its nanoparticles across Caco-2 cell model. METHODS: The Caco-2 monolayer model was used to explore the effect of time and drug concentration on the absorption of puerarin and its nanoparticeles. The drug concentration was determined by high-performance liquid chromatography and the Papp was caculated. RESULTS: The puerarin-PLGA-NP could significantly improve the absorption of puerarin. Puerarin was not only absorbed simply through passive diffusion, but also had relations with high dispersion of nanoparticles, increase of affinity and interaction with intestinal mucous membrane. CONCLUSION: The main mechanism of puerarin and its nanoparticles across Caco-2 monolayer model is passive transference. Puerarin-NP could increase the absorption of the drug in intestinal epithlial.

Magnetic resonance susceptibility weighted imaging in detecting intracranial calcification and hemorrhage.

BACKGROUND: Computed tomography (CT) is better than routine magnetic resonance imaging (MRI) in detecting intracranial calcification. This study aimed to assess the value of MR susceptibility weighted imaging (SWI) in the detection and differentiation of intracranial calcification and hemorrhage. METHODS: Enrolled in this study were 35 patients including 13 cases of calcification demonstrated by CT and 22 cases of intracerebral hemorrhage. MR sequences used in all the subjects included axial T1WI, T2WI and SWI. The phase shift (PS) of calcification and hemorrhage on SWI was calculated and their signal features on corrected phase images were compared. The sensitivity of T1WI, T2WI and SWI in detecting intracranial calcification and hemorrhage was analyzed statistically. RESULTS: The detection rate of SWI for cranial calcification was 98.2%, significantly higher than that of T1WI and T2WI. It was not significantly different from that of CT (P > 0.05). There were 49 hemorrhagic lesions at different stages detected on SWI, 30 on T2WI and 18 on T1WI. The average PS of calcification and hemorrhage was +0.734 +/- 0.073 and -0.112 +/- 0.032 respectively (P < 0.05). The PS of calcification was positive and presented as a high signal or the mixed signal dominated by a high signal on the corrected phase images, whereas the PS of hemorrhage was negative and presented as a low signal or the mixed signal dominated by a low signal. CONCLUSIONS: SWI can accurately demonstrate intracranial calcification, not dependant on CT. Being more sensitive than routine MRI in detecting micro-hemorrhage, SWI may play an important role in differentiating cerebral diseases associated with calcification or hemorrhage.

[Evaluation of whole body MRI and diffusion-weighted MRI in detecting intranodal lesions in patients with lymphoma].

OBJECTIVE: To evaluate the whole body MRI and diffusion-weighted MRI in detecting intranodal lesions in patients with lymphoma. METHODS: Whole body MRI and diffusion-weighted MRI (DWI) were performed in 23 patients with histologically proven lymphoma. A conventional coronal MRI scan from head to inguinal groove was done for whole body scanning. In the DWI, axial MRI scans were performed after segmentation based on SENSE technique, and all images were merged into whole body image reconstruction by software. RESULTS: 417 lymph nodes were detected by MRI in the 23 patients. The overall positive rate of whole body MRI and DWI was 79.1% and 89.7%, respectively. It was 70.9% versus 85.2% and 79.4% versus 90.1% for the lymph nodes of < 2 cm and 2-3 cm in diameter, with a significant difference between the two methods (P < 0.01). However, it was 94.7% versus 97.9% for the lymph nodes of > 3 cm in diameter, not significantly different between the two methods (P > 0.05). Both methods had similar sensitivity in detecting the lymph nodes in the neck, supraclavicular and infraclavicular fossae, mediastinum and axillary fossa. However, the positive rate of whole body MRI was 51.2%, 43.8% and 52.2%, significantly less sensitive than 83.7%, 71.9% and 87.0%, respectively, by DWI in detecting the lymph nodes in the retroperitoneal space, pelvic cavity and inguinal groove (all P < 0.01). CONCLUSION: Both whole body MRI and diffusion-weighted MRI have a relative high sensitivity in detecting intranodal lesions for patients with lymphoma, showing a certain value in clinical application.

Spontaneous retroperitoneal hemorrhage in a mediastinal tumor in a patient with polymyositis: a case report.

Spontaneous retroperitoneal hemorrhage is a lethal cause of acute abdomen that is most frequently related to drugs, coagulopathy and intra-abdominal tumors. In patients with polymyositis and dermatomyositis, acute abdomen is attributed to intestinal vasculitis causing ischemia, ulceration or perforation. Spontaneous retroperitoneal hemorrhage, however, has rarely been reported in patients with polymyositis. We report the case of a 65-year-old woman with newly diagnosed polymyositis and suspected thymoma who suffered from spontaneous retroperitoneal hemorrhage. She experienced two massive retroperitoneal hemorrhage episodes within 24 hours, which resulted in shock and required emergent angiographic embolization. There was no evidence of tumor, vasculitis or aneurysm from abdominal angiography and computed tomography.

Detection of activated K-ras in non-small cell lung cancer by membrane array: a comparison with direct sequencing.

The ability to detect K-ras oncogene may provide additional information for the management of patients with non-small cell lung cancer (NSCLC). In the present study, we detected the K-ras oncogene in 76 patients with NSCLC by two methods: direct sequencing of K-ras in tumor tissues and membrane array detection of the gene overexpression specific for activated K-ras in peripheral blood. The results showed that 28 (36.8%) of the 76 Taiwanese NSCLC patients had K-ras mutations, with a frequency of 36.4% (20/55) in adenocarcinomas and 38.1% (8/21) in squamous cell carcinomas. The K-ras mutations were more frequently found in smokers than in non-smokers (51.4 vs. 24.4%, P=0.015). The incidences of K-ras mutation in the subgroups of non-smokers and squamous cell carcinomas are relatively higher in Taiwan than in other countries. On the other hand, the membrane array method could positively detect circulating activated K-ras in all of the 27 NSCLC patients with K-ras mutations at codons 12, 13 and 61, and in 4 of the 48 patients with wild-type K-ras. Our results suggest that the K-ras oncogene membrane array serves as a sensitive and convenient tool for the detection of K-ras oncogene, and therefore, has a great potential for clinical applications.

Ligustilide reduces phenylephrine induced-aortic tension in vitro but has no effect on systolic pressure in spontaneously hypertensive rats.

Radix Angelica sinensis, known as Danggui in Chinese, has been used to treat cardiovascular diseases in traditional Chinese medicine for a long time. Experimental evidence showed that the essential oil of Danggui could reduce blood pressure in rabbits, cats or hypertensive dogs when given intravenously. In this study, we investigated the effects of Z-ligustilide, the main lipophilic component of the essential oil of Danggui on aortic tension induced by phenylephrine, an alpha-adrenergic agonist, in vitro and the systolic blood pressure in SHR rats. We demonstrated for the first time that ligustilide can significantly reduce the phenylephrine-induced aortic tension in vitro with IC(50) about 64 mug/ml, but has no in vivo effect on systolic blood pressure in SHR rats when administrated orally. The data on transport of ligustilide across Caco-2 monolayer suggested an efficient intestinal absorption of ligustilide in vivo, implying that the non-effectiveness of ligustilide in vivo is not due to the poor absorption in the gastrointestinal tract. Further studies on whether ligustilide is one of the main anti-hypertensive components of the essential oil are needed.

[Determination of butylidenephthalide in Ligusticum chuanxiong by HPLC].

OBJECTIVE: To determine butylidenephthalide in Ligusticum Chuanxiong with RP-HPLC. METHOD: The sample was extracted with methanol using sonication. The ESTD was used to quantify butylidenephthalide. HPLC separation was carried out in a Hypersil ODS columm (4.6 mm x 150 mm, 5 microm) , eluted at 1 mL x min(-1) with methanol-5% isopropyl alcohol (60: 40) at 25 degrees C. The detection wavelength was 230 nm. RESULT: The linear range was 0.07-0.7 microg for butylidenephthalide. The average recovery was 95.3%, and RSD was 2.3% (n =6). CONCLUSION: This method was simple and could be used to determine butylidenephthalide with satisfactory accuracy and reproducibility.

Rb deficiency accelerates progression of carcinoma of the urinary bladder in vivo and in vitro through inhibiting autophagy and apoptosis.

Urinary bladder cancer is known as a common cancer diagnosed across the world and results in significant mortality and morbidity rates among patients. The retinoblastoma (Rb) protein, as a main tumor suppressor, controls cellular responses to potentially oncogenic stimulation. Rb phosphorylation could disrupt E2F complex formation, resulting in diverse transcription factor dysfunction. In our study, we investigated how Rb is involved in controlling urinary bladder cancer progression. The results indicate that Rb expression is reduced in mice with urinary bladder tumor, and its suppression leads to urinary bladder cancer progression in vivo and in vitro. Rb mutation directly results in tumor size with lower survival rate in vivo. Rb knockdown in vitro promoted bladder tumor cell proliferation, migration and invasion. Interestingly, Rb knockout and knockdown result in autophagy and apoptosis inhibition via suppressing p53 and caspase-3 signaling pathways, enhancing bladder cancer development in vitro and in vivo. These findings reveal that Rb deficiency accelerated urinary bladder cancer progression, exposing an important role of Rb in suppressing urinary bladder cancer for treatment in the future.

Rb knockdown accelerates bladder cancer progression through E2F3 activation.

Bladder cancer is one of the most common cancers diagnosed in the world and leads to significant mortality and morbidity among affected patients. The retinoblastoma (Rb) protein is a main tumor suppressor, controlling cellular responses to potentially oncogenic stimulation. E2F3 was invariably disrupted in different human cancers for its central role in the control of cellular proliferation. Here, we investigated how Rb is integrated to control bladder cancer progression through E2F3 and p53 regulation. The results exhibit that Rb expression is lower in patients with bladder tumor, while E2F3 level is high. Rb knockdown enhanced bladder tumor cell proliferation and migration, aggravated with p53 silence. Interestingly, Rb silence results in E2F3, Myc and mTOR signaling pathway activation, contributing to bladder cancer cell proliferation and apoptosis suppression mainly through caspase-3 inhibition in vitro and in vivo. Immunohistochemical analysis revealed that Rb is highly expressed in normal bladder cells, but was repressed in tumor tissues of the bladder completely, suggesting a possible role of Rb as a tumor suppressor.

Prophenoloxidase-Mediated Ex Vivo Immunity to Delay Fungal Infection after Insect Ecdysis.

Skin immunity protects animals from airborne pathogen infection. Unlike mammals, arthropods, including insects, undergo periodic ecdysis to grow and develop. Newly molted insects emerge with unsclerotized thin cuticles but successfully escape pathogenic infections during the post-molt period. Here we show that prophenoloxidases (PPOs) in molting fluids remain bioactive on the integument and impede fungal infection after ecdysis. We found that the purified plasma PPOs or recombinant PPOs could effectively bind to fungal spores (conidia) by targeting the cell wall components chitin and ß-1,3-glucan. Pretreatment of the spores of the fungal pathogen Beauveria bassiana with PPOs increased spore hydrophilicity and reduced spore adhesion activity, resulting in a significant decrease in virulence as compared with mock infection. We also identified a spore-secreted protease BPS8, a member of peptidase S8 family of protease that degrade PPOs at high levels to benefit fungal infection, but which at lower doses activate PPOs to inhibit spore germination after melanization. These data indicate that insects have evolved a distinct strategy of ex vivo immunity to survive pathogen infections after ecdysis using PPOs in molting fluids retained on the underdeveloped and tender integument of newly molted insects for protection against airborne fungal infection.

Actein induces autophagy and apoptosis in human bladder cancer by potentiating ROS/JNK and inhibiting AKT pathways.

Human bladder cancer is a common genitourinary malignant cancer worldwide. However, new therapeutic strategies are required to overcome its stagnated survival rate. Triterpene glycoside Actein (ACT), extracted from the herb black cohosh, suppresses the growth of human breast cancer cells. Our study attempted to explore the role of ACT in human bladder cancer cell growth and to reveal the underlying molecular mechanisms. We found that ACT significantly impeded the bladder cancer cell proliferation via induction of G2/M cycle arrest. Additionally, ACT administration triggered autophagy and apoptosis in bladder cancer cells, proved by the autophagosome formation, LC3B-II accumulation, improved cleavage of Caspases/poly (ADP-ribose) polymerase (PARP). Furthermore, reduction of reactive oxygen species (ROS) and p-c-Jun N-terminal kinase (JNK) could markedly reverse ACT-induced autophagy and apoptosis. In contrast, AKT and mammalian target of rapamycin (mTOR) were greatly de-phosphorylated by ACT, while suppressing AKT and mTOR activity could enhance the effects of ACT on apoptosis and autophagy induction. In vivo, ACT reduced the tumor growth with little toxicity. Taken together, our findings indicated that ACT suppressed cell proliferation, induced autophagy and apoptosis through promoting ROS/JNK activation, and blunting AKT pathway in human bladder cancer, which indicated that ACT might be an effective candidate against human bladder cancer in future.