MRI-based bone marrow radiomics for predicting cytogenetic abnormalities in multiple myeloma

AIM

To develop a radiomics signature applied to magnetic resonance imaging (MRI)-images to predict cytogenetic abnormalities in multiple myeloma (MM).

MATERIALS AND METHODS

Patients with newly diagnosed MM were enrolled retrospectively from March 2019 to September 2022. They were categorised into the high-risk cytogenetics (HRC) group and standard-risk cytogenetics (SRC) group. The patients were allocated randomly at a ratio of 7:3 into training and validation cohorts. Volumes of interest (VOI) was drawn manually on fat suppression T2-weighted imaging (FS-T2WI) and copied to the same location of the T1-weighted imaging (T1WI) sequence. Radiomics features were extracted from two sequences and selected by reproducibility and redundant analysis. The least absolute shrinkage selection operation (LASSO) algorithm was applied to build the radiomics signatures. The performance of the radiomics signatures to distinguish HRC with SRC was evaluated by ROC curves. The area under the curve (AUC), specificity, and sensitivity were also calculated.

RESULTS

A total of 105 MM patients were enrolled in this study. The four and 11 most significant and relevant features were selected separately from T1WI and FS-T2WI sequences to build the radiomics signatures based on the training cohort. Compared to the T1WI sequence, the radiomics signature based on the FS-T2WI sequence achieved better performance with AUCs of 0.896 and 0.729 in the training and validation cohorts respectively. A sensitivity of 0.833, specificity of 0.667, and Youden index of 0.500 were achieved for the FS-T2WI radiomics signature in the validation cohort.

CONCLUSIONS

The radiomics signature based on MRI provides a non-invasive and convenient tool to predict cytogenetic abnormalities in MM patients.

Hidden magnetism uncovered in a charge ordered bilayer kagome material ScV6Sn6

Charge ordered kagome lattices have been demonstrated to be intriguing platforms for studying the intertwining of topology, correlation, and magnetism. The recently discovered charge ordered kagome material ScV6Sn6 does not feature a magnetic groundstate or excitations, thus it is often regarded as a conventional paramagnet. Here, using advanced muon-spin rotation spectroscopy, we uncover an unexpected hidden magnetism of the charge order. We observe an enhancement of the internal field width sensed by the muon ensemble, which takes place within the charge ordered state. More importantly, the muon spin relaxation rate below the charge ordering temperature is substantially enhanced by applying an external magnetic field. Taken together with the hidden magnetism found in AV3Sb5 (A = K, Rb, Cs) and FeGe kagome systems, our results suggest ubiqitous time-reversal symmetry-breaking in charge ordered kagome lattices.

Seroprevalence of antibodies to classical swine fever virus and porcine reproductive and respiratory syndrome virus in healthy pigs in Hunan Province, China

Classical swine fever (CSF) and porcine reproductive and respiratory syndrome (PRRS) are responsible for major economic losses and represent a threat to the swine industry worldwide. Routine surveillance serology for CSF and PRRS viruses is critical to maintaining the health status of sow farms in Hunan Province, which is one of the top pig production provinces in China. The aim of our study was to investigate the serological statistics of CSF virus (CSFV) and PRRS virus (PRRSV) in Hunan Province. The cohort serum samples were collected from vaccinated and unvaccinated pigs. Our findings showed that the average rates of CSFV and PRRSV antibody seropositivity were 82.2% (95% CI: 80.1-84.3) and 84.8% (95% CI: 82.5-87.1), respectively, in the immunized group and that these rates were higher than those in the unvaccinated group (58.6% for CSFV and 47.8% for PRRSV). Additionally, the level of CSFV antibody in piglet serum declined gradually with age, whereas PRRSV-specific antibody level increased initially (1 to 2 weeks old) and then declined with age (2 to 4 weeks old). In summary, we investigated the difference in CSFV/PRRSV antibody levels among piglets at various weeks old (1 to 4 weeks) to further establish the duration of maternal immunity in piglets. In addition, routine monitoring of CSFV/PRRSV antibodies in immunized pigs was carried out to evaluate the efficacy of vaccination.

Hypoxia-mediated down-regulation of miRNAs' biogenesis promotes tumor immune escape in bladder cancer

BACKGROUND

The study examines the function of hypoxia-mediated down-regulation of microRNAs (miRNAs) (mir-30c, mir-135a, and mir-27a) in the process of bladder cancer immune escape.

METHODS

Quantitative Real-time PCR (qRT-PCR) was carried out to determine gene expression levels of Drosha and Dicer under hypoxia treatment, while western blotting and flow cytometry were used to determine protein expression. Seven reported miRNAs were identified via qRT-PCR assay. Flow cytometry detection of CD3/CD4/CD8-positive expression and statistics. Enzyme-linked immunosorbent assay (ELISA) detected cellular immune factors content. Cell apoptosis was checked via flow cytometry assay. Luciferase report assay and western blot assays were both used to verify the relationship between miRNAs and Casitas B-lineage lymphoma proto-oncogene b (Cbl-b). The animal model was established and Hematoxylin-eosin (HE) staining, TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, and immunohistochemistry (IHC) assays were separately used to verify the conclusions.

RESULTS

The CD3 + /CD4 + expression was increased in the hypoxia group, while CD3 + /CD8 + expression, the cellular immune factors content Interleukin-2 (IL-2) and Tumor Necrosis Factor-α (TNFα) along with the cell apoptosis were suppressed. The protein expression of Cbl-b was found to be up-regulated in the hypoxia group. After constructing the overexpression/ knockdown of Cbl-b in peripheral blood mononuclear cell (PBMC), Cbl-b has been found to promote tumor immune escape in bladder cancer. Furthermore, Cbl-b had been identified as the co-targets of mir-30c, mir-135a, and mir-27a and down-regulation of miRNA biogenesis promotes Cbl-b expression and deactivating T cells in vitro/in vivo.

CONCLUSION

Hypoxia-mediated down-regulation of miRNAs' biogenesis promotes tumor immune escape in bladder cancer, which could bring much more advance to the medical research on tumors.

[Curcumin induces human lens epithelial cell apoptosis and cell cycle arrest by inhibiting Wnt/β-catenin signaling pathway]

OBJECTIVE

To investigate the effect of curcumin on cell cycle and apoptosis of human lens epithelial cells and the possible molecular mechanism.

OBJECTIVE

Cultured human lens epithelial cell line HLEC-SRA01/04 was treated with 20, 40 and 60 μmol/L curcumin for 24 or 48 h. The cell proliferation inhibition rate was determined using MTT assay, and the changes in cell cycle, mitochondrial membrane potential and apoptosis rate were analyzed with flow cytometry. Western blotting was used to detect the expression levels of caspase-9, caspase-3, Bcl-2, Bax, cyclin B1, CDK1, β-catenin, c-myc, and cyclin D1 in the cells.

OBJECTIVE

Curcumin concentration- and time-dependently inhibited the proliferation of in HLEC-SRA01/04 cells as compared with the control cells (P < .05). Flow cytometric analysis showed that curcumin significantly increased apoptosis rate and cell percentage in G2/M phase and lowered mitochondrial membrane potential of HLEC-SRA01/04 cells in a concentrationdependent manner (P < 0.05). The results of Western blotting showed that curcumin also concentration-dependently increased the cellular expressions of caspase-3, caspase-9 and Bax and lowered the expressions of Bcl-2, cyclin B1, CDK1 and β-catenin along with the downstream proteins cyclin D1 and c-myc in the Wnt/β-catenin signaling pathway (P < 0.05).

OBJECTIVE

Curcumin inhibits the proliferation of HLEC-SRA01/04 cells possibly by inhibiting the Wnt/β-catenin signaling pathway and causing cell cycle arrest to induce cell apoptosis.

Expression of a bacterial 3-dehydroshikimate dehydratase (QsuB) reduces lignin and improves biomass saccharification efficiency in switchgrass (Panicum virgatum L.)

BACKGROUND

Lignin deposited in plant cell walls negatively affects biomass conversion into advanced bioproducts. There is therefore a strong interest in developing bioenergy crops with reduced lignin content or altered lignin structures. Another desired trait for bioenergy crops is the ability to accumulate novel bioproducts, which would enhance the development of economically sustainable biorefineries. As previously demonstrated in the model plant Arabidopsis, expression of a 3-dehydroshikimate dehydratase in plants offers the potential for decreasing lignin content and overproducing a value-added metabolic coproduct (i.e., protocatechuate) suitable for biological upgrading.

RESULTS

The 3-dehydroshikimate dehydratase QsuB from Corynebacterium glutamicum was expressed in the bioenergy crop switchgrass (Panicum virgatum L.) using the stem-specific promoter of an O-methyltransferase gene (pShOMT) from sugarcane. The activity of pShOMT was validated in switchgrass after observation in-situ of beta-glucuronidase (GUS) activity in stem nodes of plants carrying a pShOMT::GUS fusion construct. Under controlled growth conditions, engineered switchgrass lines containing a pShOMT::QsuB construct showed reductions of lignin content, improvements of biomass saccharification efficiency, and accumulated higher amount of protocatechuate compared to control plants. Attempts to generate transgenic switchgrass lines carrying the QsuB gene under the control of the constitutive promoter pZmUbi-1 were unsuccessful, suggesting possible toxicity issues associated with ectopic QsuB expression during the plant regeneration process.

CONCLUSION

This study validates the transfer of the QsuB engineering approach from a model plant to switchgrass. We have demonstrated altered expression of two important traits: lignin content and accumulation of a co-product. We found that the choice of promoter to drive QsuB expression should be carefully considered when deploying this strategy to other bioenergy crops. Field-testing of engineered QsuB switchgrass are in progress to assess the performance of the introduced traits and agronomic performances of the transgenic plants.

[Postoperative acute laryngeal spasm in 1 cases of thyroid cancer]

Thirty-eight years old male patient. Accepted the radical thyroidectomy for thyroid cancer in our department. When surgery was ended, laryngeal spasm occurred during pulling out the tracheal intubation, the quick check of calcium was 1.87 mmol/L, after intravenous injection the calcium gluconate the laryngeal spasm was relieved. After surgery, we gave calcium gluconate intravenously and oral Caltrate D, the patient did not appear the presence of numbness, convulsions and other symptoms. The fasting serum calcium was 2.28 mmol/L and the parathyroid hormone was 18 pg/ml before the patient discharge. In this case, we should be alert to the occurrence of low calcium and laryngeal spasm.

Generation of Individual Whole-Brain Atlases With Resting-State fMRI Data Using Simultaneous Graph Computation and Parcellation

The human brain can be characterized as functional networks. Therefore, it is important to subdivide the brain appropriately in order to construct reliable networks. Resting-state functional connectivity-based parcellation is a commonly used technique to fulfill this goal. Here we propose a novel individual subject-level parcellation approach based on whole-brain resting-state functional magnetic resonance imaging (fMRI) data. We first used a supervoxel method known as simple linear iterative clustering directly on resting-state fMRI time series to generate supervoxels, and then combined similar supervoxels to generate clusters using a clustering method known as graph-without-cut (GWC). The GWC approach incorporates spatial information and multiple features of the supervoxels by energy minimization, simultaneously yielding an optimal graph and brain parcellation. Meanwhile, it theoretically guarantees that the actual cluster number is exactly equal to the initialized cluster number. By comparing the results of the GWC approach and those of the random GWC approach, we demonstrated that GWC does not rely heavily on spatial structures, thus avoiding the challenges encountered in some previous whole-brain parcellation approaches. In addition, by comparing the GWC approach to two competing approaches, we showed that GWC achieved better parcellation performances in terms of different evaluation metrics. The proposed approach can be used to generate individualized brain atlases for applications related to cognition, development, aging, disease, personalized medicine, etc. The major source codes of this study have been made publicly available at https://github.com/yuzhounh/GWC.

Effect of Spin-Draw Rate and Stretching Ratio on Polypropylene Hollow Fiber Membrane Made by Melt-Spinning and Stretching Method

A series of polypropylene hollow fiber membranes was fabricated by melt-spinning and stretching. The crystalline behavior and hard elasticity of precursor hollow fibers were studied by differential scanning calorimetry (DSC), elastic recovery and strain-stress curves. The structure and properties of membranes were investigated in detail by scanning electron microscopy (SEM), optical microscopy, pure water flux, and so on. The results showed that membranes with excellent structure and properties can be obtained at a spin-draw rate of 350 m/min and a stretching ratio of 200 %. The evolution of crystal structure was explored during the annealing and stretching processes by two-dimensional small-angle X-ray scattering (2D-SAXS). Shish-kebab structure was obtained during annealing for hollow fibers at a spin-draw rate of 350 m/min. The crystalline lamellae were destroyed and micropores were formed during the fabrication of membranes by stretching.

Production of muconic acid in plants

Muconic acid (MA) is a dicarboxylic acid used for the production of industrially relevant chemicals such as adipic acid, terephthalic acid, and caprolactam. Because the synthesis of these polymer precursors generates toxic intermediates by utilizing petroleum-derived chemicals and corrosive catalysts, the development of alternative strategies for the bio-based production of MA has garnered significant interest. Plants produce organic carbon skeletons by harvesting carbon dioxide and energy from the sun, and therefore represent advantageous hosts for engineered metabolic pathways towards the manufacturing of chemicals. In this work, we engineered Arabidopsis to demonstrate that plants can serve as green factories for the bio-manufacturing of MA. In particular, dual expression of plastid-targeted bacterial salicylate hydroxylase (NahG) and catechol 1,2-dioxygenase (CatA) resulted in the conversion of the endogenous salicylic acid (SA) pool into MA via catechol. Sequential increase of SA derived from the shikimate pathway was achieved by expressing plastid-targeted versions of bacterial salicylate synthase (Irp9) and feedback-resistant 3-deoxy-D-arabino-heptulosonate synthase (AroG). Introducing this SA over-producing strategy into engineered plants that co-express NahG and CatA resulted in a 50-fold increase in MA titers. Considering that MA was easily recovered from senesced plant biomass after harvest, we envision the phytoproduction of MA as a beneficial option to add value to bioenergy crops.

Effect of Cdc42 on myocardial ischemia-reperfusion of rats

To investigate the effects and their possible mechanisms of cell division cycle 42 (Cdc42) to neonatal rat myocardial cells subjected to the ischemia-repefusion. Neonatal rat cardiomyocytes were cultured and then subjected to the ischemia-reperfusion. Experimental groups 1. Control group; 2. Ischemia-repefusion group (I/R group); 3. Oligofectamine group (Oli group); 4. Oligofectamine and antisense oligodeoxynucleotide (AS-ODN) group (As group); 5. Oligofectamine and missense oligodeoxynucleotide (MS-ODN) group (Ms group); 6. SP600125 and Oligofectamine and AS-ODN group (SP600125/As group); 7. SP600125 and Oligofectamine and MS-ODN group (SP600125/Ms group). The cardiacmyocyte apoptosis rate was detected by AnnexinV/PI with flow cytometry. Cdc42, JNK, p-JNK, Bax and Bcl-2 were detected by western blot. In comparison with control group, Cdc42, the cardiacmyocyte apoptosis rate and phosphorylation of JNK were increased and the ratio of Bcl-2/Bax was reduced in the I/R group; Cdc42, the cardiacmyocyte apoptosis rate and phosphorylation of JNK in As group was lower than the I/R group, Oli group and the Ms group, and the ratio of Bcl-2/Bax was the highest in the four groups; Cdc42, cardiacmyocyte apoptosis rate, phosphorylation of JNK and the ratio of Bcl-2/Bax showed no differences in the I/R group, Oli group and the Ms group. Compared with As group, phosphorylation of JNK was lower in the SP600125/As group, phosphorylation of JNK in SP600125/Ms group was lower than the Ms group, and it showed no differences between the SP600125 &amp; As group and the SP600125 &amp; Ms group. Cdc42 in myocardial I/R can promote cardiacmyocyte apoptosis rate. AS-ODN of Cdc42 can decrease the cardiacmyocyte apoptosis rate in I/R. Cdc42 may played a role in myocardial I/R via JNK , Bcl-2 and Bax signal pathway.

Plasma pharmacokinetics of quinocetone in ducks after oral and intravenous administration

Quinocetone (QCT), an antimicrobial growth promoter, is widely used in food-producing animals. However, information about pharmacokinetics (PK) of QCT in ducks still remains unavailable up to now. In this study, QCT and its major metabolites (1-desoxyquinocetone, di-desoxyquinocetone and 3-methyl-quinoxaline-2-carboxylic) in ducks were studied using a simple and sensitive UHPLC-MS/MS assay. Twenty ducks were divided into two groups. (n = 10/group). One group received QCT by oral administration at dose of 40 mg/kg while another group received QCT intravenously at 10 mg/kg. Plasma samples were collected at various time points from 0 to 96 hr. QCT and its major metabolites in duck plasma samples were extracted by 1 ml acetonitrile and detected by UHPLC-MS/MS, with the gradient mobile phase that consisted of 0.1% formic acid in water (A) and acetonitrile (B). A noncompartment analysis was used to calculate the PK parameters. The results showed that following oral dosing, the peak plasma concentration (C_max ) of QCT was 32.14 ng/ml and the area under the curve (AUCINF_obs) was 233.63 (h ng)/ ml. Following intravenous dosing, the C_max , AUCINF_obs and Vss_obs were 96.70 ng/ml, 152.34 (h ng)/ ml and 807.00 L/kg, respectively. These data indicated that the QCT was less absorbed in vivo following oral administration, with low bioavailability (38.43%). QCT and its major metabolites such as 1-desoxyquinocetone and 3-methyl-quinoxaline-2-carboxylic were detected at individual time points in individual ducks, while the di-desoxyquinocetone was not detected in all time points in all ducks. This study enriches basic scientific data about pharmacokinetics of QCT in ducks after oral and intravenous administration and will be beneficial for clinical application in ducks.

Treatment of a subdural empyema complicated by intracerebral abscess due to Brucella infection

A 55-year-old male presented with fever, stupor, aphasia, and left hemiparesis. A history of head trauma 3 months before was also reported. Cranial magnetic resonance imaging revealed slight contrast enhancement of lesions under the right frontal skull plate and right frontal lobe. Because of deterioration in nutritional status and intracranial hypertension, the patient was prepared for burr hole surgery. A subdural empyema (SDE) recurred after simple drainage. After detection of Brucella species in SDE, craniotomy combined with antibiotic treatment was undertaken. The patient received antibiotic therapy for 6 months (two doses of 2 g ceftriaxone, two doses of 100 mg doxycycline, and 700 mg rifapentine for 6 months) that resulted in complete cure of the infection. Thus, it was speculated that the preexisting subdural hematoma was formed after head trauma, which was followed by a hematogenous infection caused by Brucella species.

Does gastric bypass surgery change body weight set point?

The relatively stable body weight during adulthood is attributed to a homeostatic regulatory mechanism residing in the brain which uses feedback from the body to control energy intake and expenditure. This mechanism guarantees that if perturbed up or down by design, body weight will return to pre-perturbation levels, defined as the defended level or set point. The fact that weight re-gain is common after dieting suggests that obese subjects defend a higher level of body weight. Thus, the set point for body weight is flexible and likely determined by the complex interaction of genetic, epigenetic and environmental factors. Unlike dieting, bariatric surgery does a much better job in producing sustained suppression of food intake and body weight, and an intensive search for the underlying mechanisms has started. Although one explanation for this lasting effect of particularly Roux-en-Y gastric bypass surgery (RYGB) is simple physical restriction due to the invasive surgery, a more exciting explanation is that the surgery physiologically reprograms the body weight defense mechanism. In this non-systematic review, we present behavioral evidence from our own and other studies that defended body weight is lowered after RYGB and sleeve gastrectomy. After these surgeries, rodents return to their preferred lower body weight if over- or underfed for a period of time, and the ability to drastically increase food intake during the anabolic phase strongly argues against the physical restriction hypothesis. However, the underlying mechanisms remain obscure. Although the mechanism involves central leptin and melanocortin signaling pathways, other peripheral signals such as gut hormones and their neural effector pathways likely contribute. Future research using both targeted and non-targeted 'omics' techniques in both humans and rodents as well as modern, genetically targeted, neuronal manipulation techniques in rodents will be necessary.

Nox1 promotes colon cancer cell metastasis via activation of the ADAM17 pathway

OBJECTIVE

Reactive oxygen species (ROS) generated by endogenous metabolic enzymes are involved in a variety of pathology processes, including cancer. In particular, superoxide-generating NADPH oxidase 1 (Nox1), a member of Nox enzyme family, is highly expressed in the colon tissue and has been implicated in physiological and pathophysiological states of colon cancer. However, the underlying molecular mechanism of Nox1 in the regulation of colon cancer progression remains largely unknown.

MATERIALS AND METHODS

In vitro scratch wound healing and invasion assays were used to compare the migration and invasion abilities of HT29 cells in which Nox1 protein levels were manipulated. Western blot assay was performed to detect the expression of key proteins of the EGFR-PI3K-AKT signaling pathway. Immunoprecipitation assay was performed to detect the interaction between Nox1 and ADAM17.

RESULTS

Nox1 overexpression promoted colon cancer cell growth, migration, and invasion through the EGFR-PI3K-AKT signaling pathway. At the molecular level, Nox1 regulated the expression of tumor necrosis factor-α (TNF-α) converting enzyme (TACE)/a disintegrin and metalloprotease domain 17 (ADAM17). Furthermore, Nox1 interacted with and stabilized ADAM17 from ubiquitin-mediated degradation, leading to the activation of the ADAM17 signaling pathway.

CONCLUSIONS

This study suggests that Nox1 promotes colorectal cancer metastasis by modulating the stability of ADAM17.

Comparison of efficacy of different embolic agents on uterine leiomyoma

The aim of this study was to explore the efficacies, postoperative side effects, and complications of uterine artery embolization (UAE) treatments for uterine leiomyoma (UL) with different embolic agents. The study included 107 patients with UL that were treated with UAE with polyvinyl alcohol (PVA group) or pingyangmycin lipiodol emulsion and silk-segment (PLES group). Six months later, the improvement rate of anaemia, the menstrual improvement rate, the incidence rate of fever, the disappearance rates of compression symptoms and abdominal symptoms in the PVA group were 93.8%, 94.7%, 22.0%, 60.0%, and 88.9%, respectively, which showed no significant difference from those in the PLES group (90.5%, 92.3%, 84.8%, 53.3%, and 8 1.3%, respectively). The incidence rate of fever after embolization in PVA group was significantly lower than that in PLES group (c² = 41.958, p = 0.000). However, the efficacy, improvement rate of symptoms, and postoperative side effects of two groups showed no significant difference (p > 0.05). PVA and PLES have significant efficacy for UAE treatment on patients with UL.

Association between Longevity and Element Levels in Food and Drinking Water of Typical Chinese Longevity Area

OBJECTIVES

To carrying out an integrated analysis on regional environment and human health in China and to detect the association between longevity and daily element intake from food and drinking water.

DESIGN

Cross-sectional study.

SETTING

All the 18 cities and counties in Hainan Province.

MEASUREMENTS

The distribution of elderly population and longevity indexes at a county level in Hainan Province were investigated. Quality of food and drinking water in Hainan was evaluated by comparing the chemical elements with National Standards. In addition, the association between element concentrations in food and water and longevity was examined using spearman's rank correlation.

RESULTS

The proportion of elderly people is higher in the northern part of the province compared with southern counties. Food contributes a greater proportion of daily element intake than drinking water. Compared with the National Standards, reaching rates for elements were over 85% for both food and drinking water. There was a positive correlation between daily intake of Cu, Se, and Zn from food and water and aging and longevity indexes, and a negative correlation between Pb intake and these indexes.

CONCLUSION

The quality of food and water in Hainan Province are good and that, compared with water, food is a more important source of trace elements. An appropriate supply of Cu, Se, and Zn is important, whereas excessive intake of Pb should be avoided. The findings also provide basic data to support further studies on regional variations in longevity and their relationship to diet and drinking water.

Downregulation of GAUT12 in Populus deltoides by RNA silencing results in reduced recalcitrance, increased growth and reduced xylan and pectin in a woody biofuel feedstock

BACKGROUND

The inherent recalcitrance of woody bioenergy feedstocks is a major challenge for their use as a source of second-generation biofuel. Secondary cell walls that constitute the majority of hardwood biomass are rich in cellulose, xylan, and lignin. The interactions among these polymers prevent facile accessibility and deconstruction by enzymes and chemicals. Plant biomass that can with minimal pretreatment be degraded into sugars is required to produce renewable biofuels in a cost-effective manner.

RESULTS

GAUT12/IRX8 is a putative glycosyltransferase proposed to be involved in secondary cell wall glucuronoxylan and/or pectin biosynthesis based on concomitant reductions of both xylan and the pectin homogalacturonan (HG) in Arabidopsis irx8 mutants. Two GAUT12 homologs exist in Populus trichocarpa, PtGAUT12.1 and PtGAUT12.2. Knockdown expression of both genes simultaneously has been shown to reduce xylan content in Populus wood. We tested the proposition that RNA interference (RNAi) downregulation of GAUT12.1 alone would lead to increased sugar release in Populus wood, that is, reduced recalcitrance, based on the hypothesis that GAUT12 synthesizes a wall structure required for deposition of xylan and that cell walls with less xylan and/or modified cell wall architecture would have reduced recalcitrance. Using an RNAi approach, we generated 11 Populus deltoides transgenic lines with 50 to 67% reduced PdGAUT12.1 transcript expression compared to wild type (WT) and vector controls. Ten of the eleven RNAi lines yielded 4 to 8% greater glucose release upon enzymatic saccharification than the controls. The PdGAUT12.1 knockdown (PdGAUT12.1-KD) lines also displayed 12 to 52% and 12 to 44% increased plant height and radial stem diameter, respectively, compared to the controls. Knockdown of PdGAUT12.1 resulted in a 25 to 47% reduction in galacturonic acid and 17 to 30% reduction in xylose without affecting total lignin content, revealing that in Populus wood as in Arabidopsis, GAUT12 affects both pectin and xylan formation. Analyses of the sugars present in sequential cell wall extracts revealed a reduction of glucuronoxylan and pectic HG and rhamnogalacturonan in extracts from PdGAUT12.1-KD lines.

CONCLUSIONS

The results show that downregulation of GAUT12.1 leads to a reduction in a population of xylan and pectin during wood formation and to reduced recalcitrance, more easily extractable cell walls, and increased growth in Populus.

Reduced expression of members of the mhc-i antigen processing machinery in ethnic Uighur women with cervical cancer in the Xinjiang region of China

OBJECTIVE

Cervical cancer is a major cause of mortality in Uighur women compared with Han women in the Xinjiang region of China. Although a reduction in the class i major histocompatibility complex (mhc-i) antigen processing machinery (apm) is associated with the development of cervical cancer, the mhc-i apm has not been studied in this particular group of women, who have the highest incidence rate of cervical cancer in China.

STUDY DESIGN

We used immunohistochemical staining and polymerase chain reaction amplification of viral dna from infection with the human papilloma virus (hpv) to study the expression of members of the mhc-i apm in cervical cancer sections collected from Uighur and Han women and in cervicitis samples from age-matched counterparts.

RESULTS

Expression of the molecules of interest was compared between two ethnic groups, and expression of transporter associated with antigen processing 1 and 2, heat shock protein 90, and calnexin were found to be reduced even more significantly in Han women with cervical cancer than in Uighur women with same disease. However, compared with Han women, Uighur women had a higher rate of infection with hpv 16.

CONCLUSIONS

The mhc-i apm were reduced in cervical cancer, with heterogeneity in the two ethnic groups. The reduction was more pronounced in Han women, who less frequently had hpv 16 infection, suggesting possible differences in the roles of members of the mhc-i apm and in the mechanisms of cervical cancer development in these two ethnic groups despite residence in the same region of China.

Prevalence and impact of premature ejaculation in outpatients complaining of ejaculating prematurely: using the instruments of intravaginal ejaculatory latency time and patient-reported outcome measures

This study was designed to assess the impact of premature ejaculation (PE) on a large population of men and their female partners using the instruments of intravaginal ejaculatory latency time (IELT) and patient-reported outcome (PRO) measures. A non-interventional, observational and cross-sectional field survey enrolled 2704 men with self-reported PE and their female partners from January 2010 to January 2012. PE was diagnosed by the International Society for Sexual Medicine (ISSM) criterion. IELT and sexual dysfunction were measured using a stopwatch and PRO measures, respectively. The incidence of PE in this study was 19.27%. PE negatively impacted on subjects and their partners, including reduced ejaculatory control and sexual satisfaction, and increased personal distress and interpersonal difficulty (P<0.001 for all). The severity of PE was considered worse by subjects than by their female partners (P<0.001). Reduced ejaculatory control and sexual satisfaction were considered the central themes of PE. Furthermore, a correlation was observed among the outcomes of IELT and PRO measures for subjects and their partners (absolute correlation coefficient ranged from 0.33 to 0.67). This in-depth qualitative study provides valuable insight into the PE status in Chinese men. Further research is needed to confirm and extend these results.

Loss of Arabidopsis GAUT12/IRX8 causes anther indehiscence and leads to reduced G lignin associated with altered matrix polysaccharide deposition

GAlactUronosylTransferase12 (GAUT12)/IRregular Xylem8 (IRX8) is a putative glycosyltransferase involved in Arabidopsis secondary cell wall biosynthesis. Previous work showed that Arabidopsis irregular xylem8 (irx8) mutants have collapsed xylem due to a reduction in xylan and a lesser reduction in a subfraction of homogalacturonan (HG). We now show that male sterility in the irx8 mutant is due to indehiscent anthers caused by reduced deposition of xylan and lignin in the endothecium cell layer. The reduced lignin content was demonstrated by histochemical lignin staining and pyrolysis Molecular Beam Mass Spectrometry (pyMBMS) and is associated with reduced lignin biosynthesis in irx8 stems. Examination of sequential chemical extracts of stem walls using 2D (13)C-(1)H Heteronuclear Single-Quantum Correlation (HSQC) NMR spectroscopy and antibody-based glycome profiling revealed a reduction in G lignin in the 1 M KOH extract and a concomitant loss of xylan, arabinogalactan and pectin epitopes in the ammonium oxalate, sodium carbonate, and 1 M KOH extracts from the irx8 walls compared with wild-type walls. Immunolabeling of stem sections using the monoclonal antibody CCRC-M138 reactive against an unsubstituted xylopentaose epitope revealed a bi-lamellate pattern in wild-type fiber cells and a collapsed bi-layer in irx8 cells, suggesting that at least in fiber cells, GAUT12 participates in the synthesis of a specific layer or type of xylan or helps to provide an architecture framework required for the native xylan deposition pattern. The results support the hypothesis that GAUT12 functions in the synthesis of a structure required for xylan and lignin deposition during secondary cell wall formation.

An Arabidopsis cell wall proteoglycan consists of pectin and arabinoxylan covalently linked to an arabinogalactan protein

Plant cell walls are comprised largely of the polysaccharides cellulose, hemicellulose, and pectin, along with ∼10% protein and up to 40% lignin. These wall polymers interact covalently and noncovalently to form the functional cell wall. Characterized cross-links in the wall include covalent linkages between wall glycoprotein extensins between rhamnogalacturonan II monomer domains and between polysaccharides and lignin phenolic residues. Here, we show that two isoforms of a purified Arabidopsis thaliana arabinogalactan protein (AGP) encoded by hydroxyproline-rich glycoprotein family protein gene At3g45230 are covalently attached to wall matrix hemicellulosic and pectic polysaccharides, with rhamnogalacturonan I (RG I)/homogalacturonan linked to the rhamnosyl residue in the arabinogalactan (AG) of the AGP and with arabinoxylan attached to either a rhamnosyl residue in the RG I domain or directly to an arabinosyl residue in the AG glycan domain. The existence of this wall structure, named ARABINOXYLAN PECTIN ARABINOGALACTAN PROTEIN1 (APAP1), is contrary to prevailing cell wall models that depict separate protein, pectin, and hemicellulose polysaccharide networks. The modified sugar composition and increased extractability of pectin and xylan immunoreactive epitopes in apap1 mutant aerial biomass support a role for the APAP1 proteoglycan in plant wall architecture and function.

Evolving views of pectin biosynthesis

Recent progress in the identification and characterization of pectin biosynthetic proteins and the discovery of pectin domain-containing proteoglycans are changing our view of how pectin, the most complex family of plant cell wall polysaccharides, is synthesized. The functional confirmation of four types of pectin biosynthetic glycosyltransferases, the identification of multiple putative pectin glycosyl- and methyltransferases, and the characteristics of the GAUT1:GAUT7 homogalacturonan biosynthetic complex with its novel mechanism for retaining catalytic subunits in the Golgi apparatus and its 12 putative interacting proteins are beginning to provide a framework for the pectin biosynthetic process. We propose two partially overlapping hypothetical and testable models for pectin synthesis: the consecutive glycosyltransferase model and the domain synthesis model.

Deletion of Fas protects islet beta cells from cytotoxic effects of human islet amyloid polypeptide

AIMS/HYPOTHESIS: Islet amyloid, which is mainly composed of human islet amyloid polypeptide (hIAPP), is a pathological characteristic of type 2 diabetes and also forms in cultured and transplanted islets. We used islet beta cells as well as two ex vivo models of islet amyloid formation, cultured human islets and hIAPP-expressing transgenic mouse islets with or without beta cell Fas deletion, to test whether: (1) the aggregation of endogenous hIAPP induces Fas upregulation in beta cells; and (2) deletion or blocking of Fas protects beta cells from amyloid toxicity. METHODS: INS-1, mouse or human islet cells were cultured with hIAPP alone, or with amyloid inhibitor or Fas antagonist. Non-transduced islets, and human islets or hIAPP-expressing mouse islets transduced with an adenovirus that delivers a human proIAPP-specific small interfering RNA (siRNA) (Ad-ProhIAPP-siRNA) were cultured to form amyloid. Mouse islets expressing hIAPP with or without Fas were similarly cultured. Beta cell Fas upregulation, caspase-3 activation, apoptosis and function, and islet IL-1β levels were assessed. RESULTS: hIAPP treatment induced Fas upregulation, caspase-3 activation and apoptosis in INS-1 and islet cells. The amyloid inhibitor or Fas antagonist reduced apoptosis in hIAPP-treated beta cells. Islet cells with Fas deletion had lower hIAPP-induced beta cell apoptosis than those expressing Fas. Ad-ProhIAPP-siRNA-mediated amyloid inhibition reduced Fas upregulation and IL-1β immunoreactivity in human and hIAPP-expressing mouse islets. Cultured hIAPP-expressing mouse islets with Fas deletion had similar amyloid levels, but lower caspase-3 activation and beta cell apoptosis, and a higher islet beta:alpha cell ratio and insulin response to glucose, compared with islets expressing Fas and hIAPP. CONCLUSIONS/INTERPRETATION: The aggregation of biosynthetic hIAPP produced in islets induces beta cell apoptosis, at least partially, via Fas upregulation and the Fas-mediated apoptotic pathway. Deletion of Fas protects islet beta cells from the cytotoxic effects of endogenously secreted (and exogenously applied) hIAPP.