Image scanning fluorescence emission difference microscopy based on a detector array

We propose a novel imaging method that enables the enhancement of three-dimensional resolution of confocal microscopy significantly and achieve experimentally a new fluorescence emission difference method for the first time, based on the parallel detection with a detector array. Following the principles of photon reassignment in image scanning microscopy, images captured by the detector array were arranged. And by selecting appropriate reassign patterns, the imaging result with enhanced resolution can be achieved with the method of fluorescence emission difference. Two specific methods are proposed in this paper, showing that the difference between an image scanning microscopy image and a confocal image will achieve an improvement of transverse resolution by approximately 43% compared with that in confocal microscopy, and the axial resolution can also be enhanced by at least 22% experimentally and 35% theoretically. Moreover, the methods presented in this paper can improve the lateral resolution by around 10% than fluorescence emission difference and 15% than Airyscan. The mechanism of our methods is verified by numerical simulations and experimental results, and it has significant potential in biomedical applications.

Ubiquitination and regulation of AURKA identifies a hypoxia-independent E3 ligase activity of VHL

The hypoxia-regulated tumor-suppressor von Hippel-Lindau (VHL) is an E3 ligase that recognizes its substrates as part of an oxygen-dependent prolyl hydroxylase (PHD) reaction, with hypoxia-inducible factor α (HIFα) being its most notable substrate. Here we report that VHL has an equally important function distinct from its hypoxia-regulated activity. We find that Aurora kinase A (AURKA) is a novel, hypoxia-independent target for VHL ubiquitination. In contrast to its hypoxia-regulated activity, VHL mono-, rather than poly-ubiquitinates AURKA, in a PHD-independent reaction targeting AURKA for degradation in quiescent cells, where degradation of AURKA is required to maintain the primary cilium. Tumor-associated variants of VHL differentiate between these two functions, as a pathogenic VHL mutant that retains intrinsic ability to ubiquitinate HIFα is unable to ubiquitinate AURKA. Together, these data identify VHL as an E3 ligase with important cellular functions under both normoxic and hypoxic conditions.

Punch biopsy guided by both colposcopy and HR-HPV status is more efficient for identification of immediate high-grade squamous intraepithelial lesion or worse among HPV-infected women with atypical squamous cells of undetermined significance

OBJECTIVES

To investigate the accuracy of colposcopy for diagnosing high-grade squamous intraepithelial lesion (HSIL) or worse (HSIL+) in human papillomavirus (HPV)-infected patients with atypical squamous cells of undetermined significance (ASCUS) cytology, and determine whether genotyping and viral load quantitation can be useful for detecting immediate HSIL+ risk in these patients.

STUDY DESIGN

This study included 620 cases with ASCUS and positive for high-risk (HR)-HPV within 1 month before or after cervical cytology at Qilu Hospital between February 2013 and February 2014. Based on the colposcopic impression, lesion-targeted punch biopsy, endocervical curettage biopsy or random cervical punch biopsy in four quadrants was performed on these patients within 1 month. The accuracy of colposcopy for diagnosing HSIL+ was evaluated through comparison with the biopsy results. HR-HPV status determined by Hybrid Capture 2 or HPV genotyping was analysed retrospectively as a possible predictor of HSIL+.

RESULTS

Agreement between colposcopic impression and cervical pathology was matched perfectly in 89.2% of cases (553/620), and the strength of agreement with the κ statistic was 0.698 (p<0.001). Colposcopy had high specificity (96.9%) but low sensitivity for detecting HSIL+ (67.5%). The risk of HSIL+ was significantly higher in patients with HPV-16 infection (52.3%) than in patients infected with other types of HPV (17.9%, p<0.001). HSIL+ and virus load was correlated at cut-offs (CO) of 50 relative light units (RLU)/CO and 100 RLU/CO (p=0.024 and 0.044, respectively). If considering HPV16 infection or high virus load (at 50 RLU/CO) as a diagnostic standard of HSIL+ when colposcopic impression was negative, sensitivity was improved to 74.7% and 81.0%, respectively.

CONCLUSIONS

Good agreement was found between colposcopic and pathologic diagnosis. HR-HPV genotyping or virus load is relevant to the detection of HSIL+ among HPV-infected patients with ASCUS cytology. In these patients, biopsies considering HPV-16 infection or virus load ≥50 RLU/CO may be helpful for increasing the HSIL+ detection rate.

First case of hepatopancreatic necrosis disease in pond-reared Chinese mitten crab, Eriocheir sinensis, associated with microsporidian

An epidemic of hepatopancreatic necrosis disease (HPND) with a high mortality rate (40%-50%) recently occurred in the cultured Chinese mitten crab, Eriocheir sinensis, which is a very important economic crustacean species in China. Histology revealed infection by a microsporidian parasite within the cytoplasm of the epithelial cells of the hepatopancreas. Numerous discrete inclusions in the infected cells and presumably free parasite spores were also observed. By negative staining using electron microscopy, a typical morphology of spores was observed with a protuberant front of the anchoring disc. Infection was confined to the epithelial cells of the hepatopancreas, with no other organ implicated. By sequencing the PCR products using specific primers based on conserved regions of microsporidian small subunit (18S) ribosomal DNA, it was revealed that the parasite from HPND ponds had 99% sequence identity to that of Hepatospora eriocheir. Phylogentic analysis also placed the microsporidian in the same lineage as H. eriocheir. This study reported the first case of widespread infections of H. eriocheir associated with HPND found in the pond-reared Chinese mitten crab, E. sinensis. The description of microsporidian in this important commercial host is fundamental for future consideration of factors affecting stock health and sustainability.

Phosphorylation-dependent cleavage regulates von Hippel Lindau proteostasis and function

Loss of von Hippel Lindau (VHL) protein function is a key driver of VHL diseases, including sporadic and inherited clear cell renal cell carcinoma. Modulation of the proteostasis of VHL, especially missense point-mutated VHL, is a promising approach to augmenting VHL levels and function. VHL proteostasis is regulated by multiple mechanisms including folding, chaperone binding, complex formation and phosphorylation. Nevertheless, many details underlying the regulations of VHL proteostasis are unknown. VHL is expressed as two variants, VHL30 and VHL19. Furthermore, the long-form variant of VHL was often detected as multiple bands by western blotting. However, how these multiple species of VHL are generated and whether the process regulates VHL proteostasis and function are unknown. We hypothesized that the two major species are generated by VHL protein cleavage, and the cleavage regulates VHL proteostasis and subsequent function. We characterized VHL species using genetical and pharmacological approaches and showed that VHL was first cleaved at the N-terminus by chymotrypsin C before being directed for proteasomal degradation. Casein kinase 2-mediated phosphorylation at VHL N-terminus was required for the cleavage. Furthermore, inhibition of cleavage stabilized VHL protein and thereby promoted HIF downregulation. Our study reveals a novel mechanism regulating VHL proteostasis and function, which is significant for identifying new drug targets and developing new therapeutic approaches targeting VHL deficiency in VHL diseases.

Association between high visceral fat area and postoperative complications in patients with Crohn's disease following primary surgery

AIM

The aim of this study was to determine the association between visceral fat area (VFA) on CT and postoperative complications after primary surgery in patients with Crohn's disease (CD).

METHOD

Inclusion criteria were patients with a confirmed diagnosis of CD who had preoperative abdominal CT scan. The areas of total fat, subcutaneous fat and visceral fat were measured using an established image-analysis method at the lumbar 3 (L3) level on CT cross-sectional images. Visceral obesity was defined as a visceral fat area (VFA) of ≥ 130 cm(2) . Clinical variables, intra-operative outcomes and postoperative courses within 30 days were analysed.

RESULTS

A total of 164 patients met the inclusion criteria. Sixty-three (38.4%) patients had postoperative complications. The mean age of the patients with complications (the study group) was 40.4 ± 15.4 years and of those without complications (the control group) was 35.8 ± 12.9 years (P = 0.049). There were no differences in disease location and behaviour between patients with or without complications (P > 0.05). In multivariable analysis, VFA [odds ratio (OR) = 2.69; 95% confidence interval (CI): 1.09-6.62; P = 0.032] and corticosteroid use (OR = 2.86; 95% CI: 1.32-6.21; P = 0.008) were found to be associated with postoperative complications. Patients with visceral obesity had a significantly longer operative time (P = 0.012), more blood loss (P = 0.019), longer bowel resection length (P = 0.003), postoperative ileus (P = 0.039) and a greater number of complications overall (P < 0.001).

CONCLUSION

High VFA was found to be associated with an increased risk for 30-day postoperative complications in patients with CD undergoing primary surgery.

Voxel-Based Morphometry and fMRI Revealed Differences in Brain Gray Matter in Breastfed and Milk Formula-Fed Children

BACKGROUND AND PURPOSE

Infant diets may have significant impact on brain development in children. The aim of this study was to evaluate brain gray matter structure and function in 8-year-old children who were predominantly breastfed or fed cow's milk formula as infants.

MATERIALS AND METHODS

Forty-two healthy children (breastfed: n = 22, 10 boys and 12 girls; cow's milk formula: n = 20, 10 boys and 10 girls) were studied by using structural MR imaging (3D T1-weighted imaging) and blood oxygen level-dependent fMRI (while performing tasks involving visual perception and language functions). They were also administered standardized tests evaluating intelligence (Reynolds Intellectual Assessment Scales) and language skills (Clinical Evaluation of Language Fundamentals).

RESULTS

Total brain gray matter volume did not differ between the breastfed and cow's milk formula groups. However, breastfed children had significantly higher (P < .05, corrected) regional gray matter volume measured by voxel-based morphometry in the left inferior temporal lobe and left superior parietal lobe compared with cow's milk formula-fed children. Breastfed children showed significantly more brain activation in the right frontal and left/right temporal lobes on fMRI when processing the perception task and in the left temporal/occipital lobe when processing the visual language task than cow's milk formula-fed children. The imaging findings were associated with significantly better performance for breastfed than cow's milk formula-fed children on both tasks.

CONCLUSIONS

Our findings indicated greater regional gray matter development and better regional gray matter function in breastfed than cow's milk formula-fed children at 8 years of age and suggested that infant diets may have long-term influences on brain development in children.

Acquiring Kupffer cells in mice using a MACS-based method

OBJECTIVE

This study sought to establish a new method to isolate Kupffer cells (KCs) by magnetic activated cell sorting (MACS).

METHODS

Nonparenchymal cells were acquired from C57BL/6 mice livers by a perfusion system in vivo and then stained with F4/80(+) fluorescein isothiocyanate and CD11c(-) phycoerythrin antibodies. After incubating with immunomagnetic beads, F4/80(+)CD11c(-) KCs were obtained by MACS selection. The purity was evaluated by flow cytometry, and the morphological features and vitality were analyzed in in vitro cultures.

RESULTS

Compared with traditional methods, acquiring KCs by MACS was characterized by economy, efficiency, and high purity. The F4/80(+)CD11c(-) KCs cultured in vitro also showed the typical adherent shape and excellent phagocytic ability.

CONCLUSIONS

With the 2-step method using immunomagnetic beads, we provide a new method by which KCs can be obtained from mouse liver with high purity and distinct phenotype of F4/80(+) CD.

Prevalence and risk factors of Helicobacter pylori infection in asymptomatic Chinese children: a prospective, cross-sectional, population-based study

BACKGROUND

Limited research has been published on current Helicobacter pylori infection rate in asymptomatic children in China.

AIM

To assess current Helicobacter pylori infection rate, distribution characteristics and risk factors in Chinese asymptomatic children.

METHODS

A prospective, cross-sectional, population-based study was performed from 2009 to 2011 in three cities of China. Helicobacter pylori infection was diagnosed by a stool antigen test. Multi-stage cluster random sampling was used to select asymptomatic children including neonates. Socioeconomic details were obtained through a standardised questionnaire.

RESULTS

Among total of 3491 children (0-18 years), the global infection rate was 6.8% and there were no significant differences between genders. Age specific infection rate between regions was significantly different (P < 0.05). The infection rate significantly increased with age (P for trend <0.01). It was low during the newborn (0.6%) to preschool period and was significantly increased in high school students (13.5%) (P < 0.01). Multivariable regression indicated that hand sanitisation, individually served meals, higher education level of mother, above average living space and residence in urban areas were significantly protective against infection (OR 0.749, 0.698, 0.720, 0.838 and 0.770 respectively). Conversely, consuming meals in unsanitised conditions, sharing towels, receiving pre-chewed food from the mother, artificial feeding and family history of gastrointestinal disease were significantly associated with the risk of infection (OR 1.200, 1.965, 2.002, 1.071 and 2.093 respectively).

CONCLUSIONS

Helicobacter pylori infection rate increases with age in Chinese asymptomatic children and is common after 10 years of age. The rate of infection is related to socioeconomic status.

Relationship between polyunsaturated fatty acid levels in maternal diets and human milk in the first month post-partum

BACKGROUND

The present study evaluated the relationship between dietary fatty acid (FA) intakes and human milk FA levels.

METHODS

Healthy lactating women (n = 514) from Northern China participated in the study. Dietary intake was assessed with a 24-h dietary recall questionnaire and evaluated using golden key maternal nutrition software (Wincome, Shanghai, China) and China Food Composition 2009. Human milk FA composition was determined by gas chromatography.

RESULTS

The maternal daily median intakes of linoleic acid (LA), α-linolenic acid (ALA) and arachidonic acid (AA) were 19.93 g, 3.08 g and 16.33 mg, respectively. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intakes were below the recommended levels. FA levels in 100 g of human milk were 0.363 g LA, 0.038 g γ-linolenic acid (GLA), 0.052 g dihomo γ-linolenic acid (DGLA), 0.144 g ALA, 0.079 g AA, 0.007 g EPA, 0.018 g docosatetraenoic acid (DTA) and 0.048 g DHA. Multiple linear regression analysis revealed that human milk DGLA levels were negatively correlated with dietary LA intake (β = -0.223, P = 0.030), and human milk GLA and DTA levels were negatively correlated with dietary ALA intake (β = -2.189, P = 0.031; β = -2.252, P = 0.027) after adjusting for possible confounding factors.

CONCLUSIONS

The results of the present study suggest the presence of competitive interactions between n-3 fatty acids (ALA) and n-6 fatty acids (GLA and DTA).

Influence of niche similarity on hybridization between Myriophyllum sibiricum and M. spicatum

The impact of ecological factors on natural hybridization is of widespread interest. Here, we asked whether climate niche influences hybridization between the two closely related plant species Myriophyllum sibiricum and M. spicatum. Eight microsatellite loci and two chloroplast fragments were used to investigate the occurrence of hybridization between these two species in two co-occurring regions: north-east China (NEC) and the Qinghai-Tibetan Plateau (QTP). The climate niches of the species were quantified by principal component analysis with bioclimatic data, and niche comparisons were performed between the two species in each region. Reciprocal hybridization was observed, and M. sibiricum was favoured as the maternal species. Furthermore, hybrids were rare in NEC but common in the QTP. Accordingly, in NEC, the two species were climatically distinct, and hybrids only occurred in the narrow geographical or ecological transition zone, whereas in the QTP, obvious niche overlaps were found for the two species, and hybrids occurred in multiple contact zones. This association between hybridization pattern and climate niche similarity suggests that the level of hybridization was promoted by niche overlap. Compared with the parental species, similar climate niches were found for the hybrid populations in the QTP, indicating that other environmental factors rather than climate were important for hybrid persistence. Our findings highlight the significance of climate niche with respect to hybridization patterns in plants.

Profilin1 regulates invadopodium maturation in human breast cancer cells

Invadopodia are actin-driven membrane protrusions that show oscillatory assembly and disassembly causing matrix degradation to support invasion and dissemination of cancer cells in vitro and in vivo. Profilin1, an actin and phosphoinositide binding protein, is downregulated in several adenocarcinomas and it is been shown that its depletion enhances invasiveness and motility of breast cancer cells by increasing PI(3,4)P2 levels at the leading edge. In this study, we show for the first time that depletion of profilin1 leads to an increase in the number of mature invadopodia and these assemble and disassemble more rapidly than in control cells. Previous work by Sharma et al. (2013a), has shown that the binding of the protein Tks5 with PI(3,4)P2 confers stability to the invadopodium precursor causing it to mature into a degradation-competent structure. We found that loss of profilin1 expression increases the levels of PI(3,4)P2 at the invadopodium and as a result, enhances recruitment of the interacting adaptor Tks5. The increased PI(3,4)P2-Tks5 interaction accelerates the rate of invadopodium anchorage, maturation, and turnover. Our results indicate that profilin1 acts as a molecular regulator of the levels of PI(3,4)P2 and Tks5 recruitment in invadopodia to control the invasion efficiency of invadopodia.

Chromium chloride increases insulin-stimulated glucose uptake in the perfused rat hindlimb

AIM

To determine the effect of chromium chloride (CrCl3 ) on healthy skeletal muscle glucose uptake in the absence and presence of submaximal insulin using the rat hindlimb perfusion technique.

METHODS

Sprague-Dawley rats were randomly assigned to an experimental group: basal (Bas), chromium chloride (Cr), submaximal insulin (sIns) or chromium chloride plus submaximal insulin (Cr-sIns).

RESULTS

Insulin significantly increased [H(3)]-2 deoxyglucose (2-DG) uptake in the gastrocnemius muscles. Additionally, Cr-sIns displayed greater rates of 2-DG uptake than sIns (Cr-sIns 6.86 ± 0.74 μmol g h(-1) vs. sIns 4.83 ± 0.42 μmol g h(-1)). There was no difference between Cr and Bas treatment groups. It has been speculated that chromium works to increase glucose uptake by increasing insulin signalling. We found that Akt and AS160 phosphorylation was increased in the sINS treatment group, while chromium treatment had no additional effect on Akt or AS160 phosphorylation in the absence or presence of insulin. Cr-sIns significantly increased plasma membrane GLUT4 concentration above that of sIns (Cr-sIns 72.22 ± 12.7%, sIns 53.4 ± 6.1%), but in the absence of insulin, chromium had no effect.

CONCLUSION

Exposure of healthy skeletal muscle to chromium may increase skeletal muscle insulin-stimulated GLUT4 translocation and glucose uptake. However, these effects do not appear to result from enhanced insulin signalling proximal to AS160.

Proteomic pattern changes associated with obesity-induced asthenozoospermia

Obesity, an increasingly frequent societal disease can also be accompanied by declines in spermatozoa quality and male subfecundity. To determine if there are obesity-associated proteomic changes potentially affecting sperm quality and motility, differential proteomic analysis was performed on spermatozoa from both obesity-associated asthenozoospermia and clinically healthy individuals, using a label-free quantitative LC-MS/MS approach. We resolved 1975 proteins in the human sperm proteome, amongst which, 105 proteins were less abundant, whereas 22 other proteins increased in obesity-associated asthenozoospermia. Functional category analyses indicated that the differentially expressed proteins are mainly related to cytoskeletal regulation, vesicle biogenesis, metabolism, and protein degradation involved in spermiogenesis and sperm motility. Furthermore, declines in endoplasmic reticulum protein 57 (ERp57) and actin-binding-related protein T2 (ACTRT2) expression were verified by immunofluorescence, Western blot, and flow cytometry analyses. It is evident that ERp57 is localized in the acrosome region, neck and principal piece of human spermatozoa, whereas ACTRT2 is localized in the post-acrosomal region and middle piece. Thus, these differences in protein expression in asthenozoospermia may contribute to the underlying sperm quality defects afflicting these individuals. Notably, declines in ERp57 and ACTRT2 expression in obesity-associated asthenozoospermia may play critical roles in reducing sperm motility.

Caffeinated nitric oxide-releasing lozenge improves cycling time trial performance

Boosting nitric oxide production during exercise by various means has been found to improve exercise performance. We investigated the effects of a nitric oxide releasing lozenge with added caffeine (70 mg) on oxygen consumption during steady-state exercise and cycling time trial performance using a double-blinded randomized, crossover experimental design. 15 moderately trained cyclists (7 females and 8 males) were randomly assigned to ingest the caffeinated nitric oxide lozenge or placebo 5 min before exercise. Oxygen consumption and blood lactate were assessed at rest and at 50%, 65% and 75% maximal oxygen consumption. Exercise performance was assessed by time to complete a simulated 20.15 km cycling time-trial course. No significant treatment effects for oxygen consumption or blood lactate at rest or during steady-state exercise were observed. However, time-trial performance was improved by 2.1% (p<0.01) when participants consumed the nitric oxide lozenge (2,424±69 s) compared to placebo (2,476±78 s) and without a significant difference in rating of perceived exertion. These results suggest that acute supplementation with a caffeinated nitric oxide releasing lozenge may be a practical and effective means of improving aerobic exercise performance.

Impaired white matter development in extremely low-birth-weight infants with previous brain hemorrhage

BACKGROUND AND PURPOSE

Brain hemorrhage is common in premature infants. The purpose of the study is to evaluate white matter development in extremely low-birth-weight infants with or without previous brain hemorrhage.

MATERIALS AND METHODS

Thirty-three extremely low-birth-weight infants were prospectively enrolled and included in this institutional review board-approved study. Another 10 healthy term infants were included as controls. The medical records of the extremely low-birth-weight infants were reviewed for sonography diagnosis of intraventricular hemorrhage. All infants had an MR imaging examination at term-equivalent age for detection of previous hemorrhage, and their white matter was scored and compared among different groups. DTI measured fractional anisotropy values were also compared voxelwise by tract-based spatial statistics.

RESULTS

Compared with controls, the white matter score was not significantly different in extremely low-birth-weight infants without blood deposition on MR imaging (P = .17), but was significantly worse in extremely low-birth-weight infants with blood deposition on MR imaging but no intraventricular hemorrhage diagnosis by sonography (P = .02), in extremely low-birth-weight infants with grade 1 or 2 intraventricular hemorrhage on sonography (P = .003), and in extremely low-birth-weight infants with grade 3 or 4 intraventricular hemorrhage on sonography (P = .0001). Extremely low-birth-weight infants without blood deposition on MR imaging did not show any white matter regions with significantly lower fractional anisotropy values than controls. Extremely low-birth-weight infants with blood deposition on MR imaging, but no intraventricular hemorrhage diagnosis, did show white matter regions with significantly lower fractional anisotropy values, and extremely low-birth-weight infants with intraventricular hemorrhage diagnosis had widespread white matter regions with lower fractional anisotropy values.

CONCLUSIONS

Previous brain hemorrhage is associated with abnormal white matter in extremely low-birth-weight infants at term-equivalent age, and sonography is not sensitive to minor hemorrhages that are sufficient to cause white matter injury.

Polymorphisms of inflammation-related genes and colorectal cancer risk: a population-based case-control study in China

The previous studies found that chronic inflammation related to an increased risk of colorectal cancer (CRC). This study aims to explore the associations of polymorphisms in inflammation-related genes (IL10, IL10RA, IL6R, TNFRSF1A, TNFRSF1B, LTA and IL4) and their interactions with the risk of colorectal cancer among Chinese population. A population-based case-control study including 299 cases and 296 controls was conducted from January 2001 to December 2009. Multivariate unconditional logistic regression was used to analyse the association of nine SNPs in inflammation-related genes with the risk of CRC, colon cancer and rectal cancer, respectively. Generalized multifactor dimensionality reduction (GMDR) was implemented to explore the gene-gene interactions among all SNPs on CRC. A decreased risk of colorectal cancer in subjects with rs1800872 AC genotype of IL10 (OR = 0.643, 95%CI = 0.453, 0.912) or AC/CC genotype (OR = 0.636, 95%CI = 0.457, 0.885) was observed, compared with those with AA genotype. Meanwhile, similar associations were observed between rs1800872 and rectal cancer. Additionally, in rs1061624 of TNFRSF1B gene, AG genotype (OR=0.566; 95% CI= 0.362, 0.885) and AG/GG genotype (OR=0.638; 95% CI=0.420, 0.971) were significantly associated with a decreased risk of rectal cancer, respectively. Our findings indicated that mutants in IL10 and TNFRSF1B genes may change the CRC risk. However, there is no interaction between inflammation-related genes on CRC risk.