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The purpose of this study was to investigate the feasibility of two-dimensional (2D) navigated, interleaved multishot echo-planar imaging (EPI) to enhance kidney diffusion-weighted imaging (DWI) in rats at 7.0 T. Fully sampled interleaved four-shot EPI with 2D navigators was tailored for kidney DWI (Sprague-Dawley rats, n = 7) on a 7.0-T small bore preclinical scanner. The image quality of four-shot EPI was compared with T(2) -weighted rapid acquisition with relaxation enhancement (RARE) (reference) and single-shot EPI (ss-EPI) without and with parallel imaging (PI). The contrast-to-noise ratio (CNR) was examined to assess the image quality for the EPI approaches. The Dice similarity coefficient and the Hausdorff distance were used for evaluation of image distortion. Mean diffusivity (MD) and fractional anisotropy (FA) were calculated for renal cortex and medulla for all DWI approaches. The corticomedullary difference of MD and FA were assessed by Wilcoxon signed-rank test. Four-shot EPI showed the highest CNR among the three EPI variants and lowest geometric distortion versus T(2) -weighted RARE (mean Dice: 0.77 for ss-EPI without PI, 0.88 for ss-EPI with twofold undersampling, and 0.92 for four-shot EPI). The FA map derived from four-shot EPI clearly identified a highly anisotropic region corresponding to the inner stripe of the outer medulla. Four-shot EPI successfully discerned differences in both MD and FA between renal cortex and medulla. In conclusion, 2D navigated, interleaved multishot EPI facilitates high-quality rat kidney DWI with clearly depicted intralayer and interlayer structure and substantially reduced image distortion. This approach enables the anatomic integrity of DWI-MRI in small rodents and has the potential to benefit the characterization of renal microstructure in preclinical studies.

Background and aim Nonattendance of outpatient colonoscopy leads to inefficient use of health-care resources. We aimed to study the effectiveness of using Short Message Service (SMS) reminder prior in patients scheduled for outpatient colonoscopy on their nonattendance rate. Methods Patients who scheduled for an outpatient colonoscopy and had access of SMS were recruited from three clinics in Hong Kong. Patients were randomized to SMS group and standard care (SC) group. All patients were given a written appointment slip on the booking date. In addition, patients in the SMS group received an SMS reminder 7-10 days before their colonoscopy appointment. Patients' demographics, attendance, colonoscopy completion, and bowel preparation quality were recorded. Logistic regression was performed to identify predictors of nonattendance. Results From November 2013 to October 2019, a total of 2225 eligible patients were recruited. A total of 1079 patients were allocated to the SMS group and 1146 to the SC group. The nonattendance rate of patients in the SMS group was significantly lower than that in the SC group (8.9% vs 11.9%, P = 0.022). There were no significant differences in their baseline characteristics and colonoscopy completion rate and bowel preparation quality. A trend towards a higher rate of adequate bowel preparation was observed in the SMS group when compared with the SC group (69.9% vs 65.8%, P = 0.053). Independent predictors for nonattendance included younger age, underprivilege, and existing diabetes. Conclusions An SMS reminder for outpatient colonoscopy is effective in reducing the nonattendance rate and may potentially improve the bowel preparation quality.

Idiopathic basal ganglia calcification is a brain calcification disorder that has been genetically linked to autosomal dominant mutations in the sodium-dependent phosphate co-transporter, SLC20A2. The mechanisms whereby deficiency of Slc20a2 leads to basal ganglion calcification are unknown. In the mouse brain, we found that Slc20a2 was expressed in tissues that produce and/or regulate cerebrospinal fluid, including choroid plexus, ependyma and arteriolar smooth muscle cells. Haploinsufficient Slc20a2 +/- mice developed age-dependent basal ganglia calcification that formed in glymphatic pathway-associated arterioles. Slc20a2 deficiency uncovered phosphate homeostasis dysregulation characterized by abnormally high cerebrospinal fluid phosphate levels and hydrocephalus, in addition to basal ganglia calcification. Slc20a2 siRNA knockdown in smooth muscle cells revealed increased susceptibility to high phosphate-induced calcification. These data suggested that loss of Slc20a2 led to dysregulated phosphate homeostasis and enhanced susceptibility of arteriolar smooth muscle cells to elevated phosphate-induced calcification. Together, dysregulated cerebrospinal fluid phosphate and enhanced smooth muscle cell susceptibility may predispose to glymphatic pathway-associated arteriolar calcification.

Although the rates of cervical squamous cell carcinoma have been declining, the rates of cervical adenocarcinoma are increasing in some countries. Outcomes for advanced cervical adenocarcinoma remain poor. Precision mapping of genetic alterations in cervical adenocarcinoma may enable better selection of therapies and deliver improved outcomes when combined with new sequencing diagnostics. We present whole-exome sequencing results from 15 cervical adenocarcinomas and paired normal samples from Hong Kong Chinese women. These data revealed a heterogeneous mutation spectrum and identified several frequently altered genes including FAT1, ARID1A, ERBB2 and PIK3CA. Exome sequencing identified human papillomavirus (HPV) sequences in 13 tumors in which the HPV genome might have integrated into and hence disrupted the functions of certain exons, raising the possibility that HPV integration can alter pathways other than p53 and pRb. Together, these provisionary data suggest the potential for individualized therapies for cervical adenocarcinoma based on genomic information.

The relationship between body mass index (BMI) and fracture risk is controversial. We sought to investigate the effect of collinearity between BMI and bone mineral density (BMD) on fracture risk, and to estimate the direct and indirect effect of BMI on fracture with BMD being the mediator. The study involved 2199 women and 1351 men aged 60 years or older. BMI was derived from baseline weight and height. Femoral neck BMD was measured by dual-energy X-ray absorptiometry (DXA; GE-LUNAR, Madison, WI, USA). The incidence of fragility fracture was ascertained by X-ray reports from 1991 through 2012. Causal mediation analysis was used to assess the mediated effect of BMD on the BMI-fracture relationship. Overall, 774 women (35% of total women) and 258 men (19%) had sustained a fracture. Approximately 21% of women and 20% of men were considered obese (BMI ≥ 30). In univariate analysis, greater BMI was associated with reduced fracture risk in women (hazard ratio [HR] 0.92; 95% confidence interval [CI], 0.85 to 0.99) and in men (HR 0.77; 95% CI, 0.67 to 0.88). After adjusting for femoral neck BMD, higher BMI was associated with greater risk of fracture in women (HR 1.21; 95% CI, 1.11 to 1.31) but not in men (HR 0.96; 95% CI, 0.83 to 1.11). Collinearity had minimal impact on the BMD-adjusted results (variance inflation factor [VIF] = 1.2 for men and women). However, in mediation analysis, it was found that the majority of BMI effect on fracture risk was mediated by femoral neck BMD. The overall mediated effect estimates were −0.048 (95% CI, −0.059 to −0.036; p

Title. Childbirth-related fatigue trajectories during labour. Aim. This paper is a report on a study identifying trajectories of childbirth-related fatigue intensity changes over time and the influencing factors related to specific trajectory patterns. Background. Childbirth is a period of time that encompasses considerable physiological and psychological fatigue, often having an adverse impact on women in labour. Empirical studies on this issue are scarce. How childbirth-related fatigue changes over time, and factors influencing fatigue development, remain unclear. Method. A prospective, correlational design with repeated measures was used. Data were collected by self-reported measures and laboratory analysis of blood specimens. From December 2004 to November 2005 a convenience sample of 209 low-risk pregnant Taiwanese women was followed throughout the labour process. Repeated measures of fatigue were analysed by using a semiparametric mixture model. Variables explaining trajectory class membership were identified by means of logistic regression. Results. Two distinct trajectories of childbirth-related fatigue were identified: low intensity (30·8% of women) and high intensity (69·2% of women). Fatigue level of both classes intensified following labour. The fastest period of fatigue-increasing rate was in the active phase. After birth, fatigue levels in the high-fatigue intensity class remained high. Primiparas in the high-fatigue intensity class experienced significantly more anxiety and higher lactate concentration at admission than the low-intensity class. Conclusion. Caregivers should endeavour to prevent high levels of fatigue once women enter the labour phase. Women who present with high fatigue at onset of labour should be targeted for early intervention, especially in the period of rapid fatigue increase.

Background. Much has been written about the anxiety of pregnant women undergoing maternal serum screening, but little has focused on the maternal self. Aims. The purpose of this study was to explore how the maternal self was affected by abnormal results of prenatal screening. Design. A qualitative design was used, based upon a grounded theory method. Methods. Twenty-seven women undergoing maternal serum screening engaged in qualitative interviews about how abnormal results affected them and their family life. Results. This study identified three forms of maternal self in women who had been informed of abnormal results of maternal serum screening. The three forms of maternal self could be described as self-stigmatizing, self-conflicting and self-knowledgeable. Conclusion. The self-stigmatizing and self-conflicting resulted from painful body image. The pregnant women responded to this vulnerability by reflecting on their experiences and constituting self-knowledgeable. Relevance to clinical practice. This study demonstrated that ethical issues were implicit in prenatal counselling in terms of various forms of maternal self. Understanding the self-perceptions of pregnant women coping with an increased risk of Down Syndrome could be very significant in delivering prenatal genetic counselling.

A facile route for synthesizing a diverse array of cargo‐loaded polymer capsules using polymer‐stabilized calcium carbonate particles is introduced by Frank Caruso and co‐workers in article number 1400007. Cargo, ranging from anti‐cancer drugs to plasmid DNA, could be loaded in high quantities, making this technique promising for a variety of applications.

Aims Cysteamine is used to reduce tissue cystine content in patients suffering from nephropathic cystinosis. The objectives of the current study were to investigate pharmacokinetics and pharmacodynamics of cysteamine bitartrate in children and young adults with nephropathic cystinosis. Methods Cysteamine bitartrate was administered to 11 cystinosis patients at their regular dose level in a single-dose, open-label, steady-state study. Blood samples were collected and analysed for plasma cysteamine and white blood cell cystine content and pharmacokinetic and pharmacodynamic parameters estimated by NONMEM analysis using a linked pharmacokinetic–pharmacodynamic model. Results Cysteamine was rapidly cleared from the plasma (mean CL/F = 32.3 ml min−1 kg−1, range = 17.3–52.2), appeared to be extensively distributed (mean Vss/F = 15.1 l, range 2.7–32.3) and exhibited a mean Tmax of 1.4 h. White blood cell cystine content post-dosing was significantly decreased compared with pre- and post-dose values (average decrement approximately 47%). A counter-clockwise hysteresis was noted in all patients, suggestive of a lag time (mean Tlag = 0.44 h, range 0.22–0.92) between drug concentration and effect. Conclusions The results of this study establish that cysteamine is rapidly cleared from the plasma but that an every 6 h dosing interval adequately maintains white blood cell cystine content below the target of 1 nmol cystine per mg protein.

Loss of heterozygosity (LOH) at chromosome 3p21 is frequent in cervical cancers. The candidate tumor suppressor gene, RASSF1A located at 3p21.3, is found to be inactivated in several major human cancers, implicating its significance in carcinogenesis. We aimed to investigate the status of RASSF1A in cervical cancers. The mutation and methylation status of RASSF1A were analysed in 4 cervical cancer cell lines, 50 primary cervical cancers including 33 squamous cell carcinoma (SCC), 17 adenocarcinoma (AC) and 11 normal controls. The primary cancer samples were also detected for LOH at 3p21 and human papillomavirus (HPV). Hypermethylation of RASSF1A was detected in 30% of SCC, 12% of AC and in 1 of the 4 cancer cell lines but was absent in all normal cases. Methylation of the cancer cell line was associated with loss of gene expression, which was restored by demethylation. About 67% (8 of 12) of hypermethylated primary cancers showed concomitant LOH at 3p21. No somatic mutation was found in all primary cancer samples or cell lines but 2 cases showed germline polymorphism at codon 133. Oncogenic HPV DNAs were found in most cancer samples. No correlation was detected between RASSF1A-hypermethylation or LOH at 3p21 and age of patient, HPV genotype, tumor grade and stage. Hypermethylation of RASSF1A occurs in a subset of cervical cancers, among which concomitant LOH at 3p21 is common. The results supported that RASSF1A may be one of the cervical cancer-related tumor suppressor genes located at 3p21 regions.

Objective To compare plasma catecholamine (noradrenaline and adrenaline) levels in pre-eclamptic to normotensive pregnancy, and to study the activity of synthetic enzymes for catecholamines in placental and trophoblastic cell cultures. We postulated that catecholamines might be an important signal secreted by the fetoplacental unit in pre-eclampsia. Methods We recruited 12 women with pre-eclampsia and 12 pregnant women with nonproteinuric hypertension undergoing delivery by caesarean section, 23 normotensive women undergoing elective caesarean section at term, and 26 normotensive primigravid women with ongoing pregnancies at gestations equivalent to those women with pre-eclampsia. We measured venous blood concentrations of catecholamines. Following delivery, we studied tyrosine hydroxylase (the rate limiting enzyme for catecholamine synthesis) activity in placental tissue of these women as well as from four eclamptic women not in the observer study. We used Northern blot analysis to quantify mRNA for tyrosine hydroxylase and dopamine-β-hydroxylase (D-P-H, a non-rate-limiting synthetic enzyme for catecholamine) in placental tissue, as well as in trophoblast cells in primary culture and trophoblast cell lines. Results Venous blood concentrations of noradrenaline were significantly higher in pre-eclamptic women compared with normotensive women. Tyrosine hydroxylase activity was greater in placental tissue from pre-eclamptic and eclamptic compared with normotensive pregnancies, as were mRNA levels for this enzyme. The mRNA levels for the non-rate-limiting D-β-H in women with pre-eclampsia were similar to those in normotensive pregnancies. First trimester trophoblast cells in primary culture and trophoblast cell lines transcript mRNA for tyrosine hydroxylase and D-β-H. Conclusions Trophoblasts have the capacity to secrete catecholamines, and we found increased activity of the rate-limiting synthetic enzyme in placental tissue from pre-eclamptic pregnancies. We postulate that the higher levels of catecholamines we found in the plasma of women with pre-eclampsia might be of placental origin. We hypothesise that in pre-eclampsia ischaemic trophoblast tissue secretes catecholamines as a physiological signal to increase maternal blood flow to the fetoplacental unit, which itself is spared the vasoconstrictor effects of catecholamines (placental vessels are known to be unresponsive to catecholamines). However, since the basic pathology—defective trophoblast invasion—is not corrected, the increased blood flow fails to resolve the ischaemia, and the secretion of catecholamines is therefore sustained or even enhanced. Noradrenaline is known to cause lipolysis. This results in breakdown of triglycerides to free fatty acids, which are oxidized to lipid peroxides. The latter are cytotoxic and cause widespread endothelial cell damage and dysfunction, culminating in the clinical syndrome of pre-eclampsia.

Inorganic phosphate (Pi) is required for cells, and as a negatively-charged anion, must be actively transported into the cell. The highly-homologous and ubiquitously-expressed transmembrane type III sodium-dependent inorganic phosphate transporters (PiT) PiT-1 (also called Slc20a1 or Glvr-1) and PiT-2 (also called Slc20a2 or Ram-1) are proposed to have a general “housekeeping” function of transporting Pi into cells (reviewed in Collins, et al., 2004). Inorganic phosphate additionally plays a role in diseases where ectopic calcification occurs, as fluctuations in mineral metabolisms are risk factors. Hyperphosphatemia is correlated with severe coronary calcification in patients with end-stage renal disease (Shigematsu, et al., 2003; Tomiyama, et al., 2006). Studies into the function of PiT-1 uncovered an essential role in human vascular smooth muscle cell calcification, as cells with reduced PiT-1 levels had reduced susceptibility to phosphate-induced calcification (Li, et al., 2006). Supporting a role for PiT-1 specifically in ectopic calcification, a recent study of Werner Syndrome patients with subcutaneous calcification had overexpression of PiT-1 in their skin (Honjo, et al., 2008). Thus, animal models to examine the physiological and potential pathological role of PiT- 1 are of great interest. Since there were no available knockout mice of PiT-1, this is the first report of the creation of conditional (PiT-1flox) and null (PiT-1Δe3,4) alleles in the mouse model. Here we describe the generation of a murine PiT-1 conditional allele with loxP sites flanking exons 3 and 4, allowing for the conditional deletion of these exons by Cre recombinase. The mouse PiT-1 gene consists of eleven exons and spans over 12.8 kb. Ten of these eleven exons code for a protein of 681 amino acid residues and has at least ten transmembrane domains (Boyer, et al., 1998). Amino acid residues critical for Pi transport have been determined for PiT-2 and include D28, E68, S113, D506, E575, and S593 (Bottger and Pedersen, 2002; Bottger and Pedersen, 2005; Salaun, et al., 2004); these sites are conserved in PiT-1 and thus, would also be predicted to be critical for Pi transport. Removal of exons 3 and 4 in the PiT-1 gene results in a shift in the protein reading frame after position 116 and the creation of an early stop codon after position 120; this truncation removes four of the six residues involved in Pi transport and 83% of the full-length protein. Thus, this PiT-1 recombined allele is predicted to be a null allele. To generate the conditional allele of PiT-1, a targeting vector was constructed where a loxP site was placed upstream of exon 3 and a pGK-gb2-neomycin (Neo) resistance cassette flanked by loxP and FRT sites was placed downstream of exon 4, with Neo being in opposite orientation to the PiT-1 reading frame: this is the PiT-1flox-neo allele (Fig. 1a). The targeting vector was linearized and electroporated into iTLBA1 mouse embryonic stem (ES) cells and neomycin-resistant colonies were screened via PCR for confirmation of correct targeting of the short and long homology arms (Fig. 1b and c, respectively). Though a number of ES cell colonies had recombination of the short homology arm (Fig. 1b), not all had recombination of the long arm (clones 112 and 311) (Fig. 1c). Two clones that had recombination of both arms (clones 111 and 221) were selected for microinjection and produced chimera offspring. Germline transmission of the conditional allele PiT-1flox-neo from clone 111 was confirmed by PCR screening (data not shown). Fig. 1 Generation of the PiT-1flox-neo allele. (a) A genomic sequence (shown to scale) containing exons 2-4 was subcloned for targeting vector construction and a loxP site was placed between exons 2 and 3, while a Neo cassette (in reverse orientation) flanked ... The PiT-1+/flox-neo mouse was bred to a FLP1 mouse line to remove the Neo cassette via the FRT sites and generated the PiT-1flox allele in somatic and germ tissue. PiT-1flox heterozygous animals were bred and wildtype (WT), heterozygous, and homozygous progeny were produced at Mendelian ratio (Table 1). PCR analysis using primers that flank the loxP sites were able to detect the 3′ insertion and removal of the Neo cassette leaving the 5′ loxP site and a FRT site (Fig. 2a and b). Mice heterozygous and homozygous for the conditional allele were viable, healthy, fertile, and grossly indistinguishable from wildtype littermates. Both of the loxP sites are functional, as exposure to Cre recombines the allele into the null allele (data not shown). Fig. 2 Alleles from Cre and FLP-mediated recombination and the PCR strategy used to identify them. (a) WT (top), PiT-1flox (middle), and PiT-1Δe3,4 (bottom) alleles (to scale) and relative placement of the primers (arrows) used to genotype them. (b) ... Table 1 Ratio of wildtype (WT), heterozygous, and homozygous offspring at postnatal day (P) 21 from heterozygous matings. The PiT-1+/flox-neo mouse was additionally bred to a Cre mouse line to produce the PiT-1Δe3,4 allele in somatic and germ tissues. PiT-1Δe3,4 heterozygous mice were bred, but only WT and heterozygous progeny were born; the absence of PiT-1 null offspring was statistically significant (p

Polymer microcapsules are of particular interest for applications including self‐healing coatings, catalysis, bioreactions, sensing, and drug delivery. The primary way that polymer capsules can exhibit functionality relevant to these diverse fields is through the incorporation of functional cargo in the capsule cavity or wall. Diverse functional and therapeutic cargo can be loaded into polymer capsules with ease using polymer‐stabilized calcium carbonate (CaCO3) particles. A variety of examples are demonstrated, including 15 types of cargo, yielding a toolbox with effectively 500+ variations. This process uses no harsh reagents and can take less than 30 min to prepare, load, coat, and form the hollow capsules. For these reasons, it is expected that the technique will play a crucial role across scientific studies in numerous fields.