Electronic screening-enhanced hole pairing in two-leg spin ladders studied by high-resolution resonant inelastic x-ray scattering at Cu M edges

We study the electronic screening mechanisms of the effective Coulomb on-site repulsion in hole-doped Sr(14)Cu(24)O(41) compared to undoped La(6)Ca(8)Cu(24)O(41) using polarization dependent high-resolution resonant inelastic x-ray scattering at Cu M edges. By measuring the energy of the effective Coulomb on-site repulsion and the spin excitations, we estimate superexchange and hopping matrix element energies along rungs and legs, respectively. Interestingly, hole doping locally screens the Coulomb on-site repulsion reducing it by as much as 25%. We suggest that the increased ratio of the electronic kinetic to the electronic correlation energy contributes to the local superexchange mediated pairing between holes.

A second-generation genetic linkage map for bighead carp (Aristichthys nobilis) based on microsatellite markers

Bighead carp (Aristichthys nobilis) is an important aquaculture fish worldwide. Genetic linkage maps for the species were previously reported, but map resolution remained to be improved. In this study, a second-generation genetic linkage map was constructed for bighead carp through a pseudo-testcross strategy using interspecific hybrids between bighead carp and silver carp. Of the 754 microsatellites genotyped in two interspecific mapping families (with 77 progenies for each family), 659 markers were assigned to 24 linkage groups, which were equal to the chromosome numbers of the haploid genome. The consensus map spanned 1917.3 cM covering 92.8% of the estimated bighead carp genome with an average marker interval of 2.9 cM. The length of linkage groups ranged from 52.2 to 133.5 cM with an average of 79.9 cM. The number of markers per linkage group varied from 11 to 55 with an average of 27.5 per linkage group. Normality tests on interval distances of the map showed a non-normal marker distribution; however, significant correlation was found between the length of linkage group and the number of markers below the 0.01 significance level (two-tailed). The length of the female map was 1.12 times that of the male map, and the average recombination ratio of female to male was 1.10:1. Visual inspection showed that distorted markers gathered in some linkage groups and in certain regions of the male and female maps. This well-defined genetic linkage map will provide a basic framework for further genome mapping of quantitative traits, comparative mapping and marker-assisted breeding in bighead carp.

Establishing HbA1c -mean blood glucose formulae for patients on continuous ambulatory peritoneal dialysis

AIM

To determine the relationship between HbA1c and mean blood glucose concentrations by using HbA1c -mean blood glucose formulae for people on continuous ambulatory peritoneal dialysis.

METHODS

A total of 305 people on continuous ambulatory peritoneal dialysis, including 13 people with Type 1 diabetes mellitus, 161 people with Type 2 diabetes mellitus and 131 people without diabetes, from a single peritoneal dialysis centre at the First Affiliated Hospital of Sun Yat-sen University, were enrolled between January 2006 and June 2011. Serum HbA1c concentration was measured quarterly and other laboratory variables, including blood glucose, were measured every month. The formulae were established using regression analysis and adjusted for other factors. The estimated blood glucose level calculated using our formulae was compared with that using previous formulae namely the Diabetes Control and Complications Trial and A1c -Derived Average Glucose formulae for people not on dialysis and the Hoshino formula for people on haemodialysis.

RESULTS

The HbA1c -mean blood glucose formulae obtained by linear regression analysis were: 1) mBGmmol/l = 0.107 × HbA1c (mmol/mol) + 1.764 [adjusted R(2) (Radj2)  = 0.494]; 2) mBGmmol/l  = 0.101 × HbA1c  (mmol/mol) - 0.001 × Cr (μmol/l) + 2.850 (Radj2 = 0.507); 3) mBGmmol/l  = 0.102 × HbA1c  (mmol/mol) - 0.095 × Alb (g/l) + 5.394 (Radj2 = 0.521); and 4) mBGmmol/l  = 0.099 × HbA1c (mmol/mol) - 0.001 × Cr (μmol/l)-0.084 × Alb (g/l) + 5.754 (Radj2 = 0.526), where mBG is mean blood glucose, Cr is serum creatinine and Alb is serum albumin. These new formulae performed as well as or better than previous formulae.

CONCLUSIONS

The relationship between HbA1c and mean blood glucose for people on continuous ambulatory peritoneal dialysis differs from that for people not on dialysis or for those on haemodialysis. Clinicians and patients can determine glycaemic control targets by applying our formulae.

Antiemesis effect and brain fMRI response of gastric electrical stimulation with different parameters in dogs

BACKGROUND

The aims of this study were to investigate the effect of gastric electrical stimulation (GES) with different parameters on emesis induced by apomorphine, and possible center mechanisms by brain functional magnetic resonance imaging (fMRI).

METHODS

Six dogs implanted with electrodes on gastric serosa were used in this study. Part 1: Apomorphine was injected in the control session and GES sessions. GESs with different parameters were applied in GES session. Gastric slow waves and emesis and behaviors suggestive of nausea were recorded in each session. Part 2: Each dog was anesthetized and given GESs with different parameters or sham stimulation for 15 min after baseline (5 min), respectively. The location of cerebral activation induced by GES was investigated by fMRI.

KEY RESULTS

Apomorphine induced emesis and behaviors suggestive of nausea, and gastric dysrhythmia. The emesis frequency in control session was 5.5 ± 0.99, and symptoms score was 22.17 ± 1.01. GES with short pulse and long pulse could not improve emesis and symptoms induced by apomorphine. The emesis frequency (4.5 ± 0.76 in short pulse and 6.33 ± 1.05 in long pulse) and symptoms scores had no significant difference compared to control session (each p > 0.05). GES with trains of short pulse reduced emesis time frequency (3.83 ± 0.7, p = 0.042 vs control) and symptoms score (p = 0.037 vs control) obviously. Brain fMRI showed that GES with short pulse and long pulse activated brain stem region, and trains of short pulse made amygdala and occipital lobe activation.

CONCLUSIONS & INFERENCES

Apomorphine induced emesis and gastric dysrhythmia. GES with trains of short pulses relieves emetic responses through activation of amygdala region.

Linezolid in the treatment of extensively drug-resistant tuberculosis

PURPOSE

To investigate the linezolid (LZD) treatment outcome and correlation between in vitro susceptibility to LZD and clinical outcome.

METHODS

We retrospectively reviewed records of tuberculosis (TB) patients who received treatment with linezolid between March 2012 and February 2013.

RESULTS

A total of 43 extensively drug-resistant (XDR) TB patients identified by drug susceptibility testing were enrolled in this study, including 15 (34.9 %) received LZD as part of individualized treatment regimens. Among the 43 XDR TB patients, 15 patients (34.9 %) obtained favorable clinical outcome, including 9 (60.0 %) from LZD group and 6 (21.4 %) from control group without LZD. Statistical analysis revealed that the percentage of favorable outcomes of LZD group was significantly higher than that of control group (P = 0.011). Furthermore, we analyzed the LZD minimum inhibitory concentrations of Mycobacterium tuberculosis (MTB) isolates from patients in LZD group and identified 4 (26.7 %) resistant to LZD. All of the patients with LZD resistance harbored adverse clinical outcome, while most of the patients infected with LZD sensitive MTB harbored favorable clinical outcome (81.8 %, 9/11). Statistical analysis revealed that the percentage of favorable outcome among the patients with LZD resistance was statistically lower than that among the LZD susceptible group (P = 0.011).

CONCLUSION

This study demonstrates that linezolid has efficacy against XDR pulmonary TB patients, even in shorter duration of administration. The XDR TB patients infected with LZD-resistant isolates were more likely to obtain the adverse clinical outcome under the treatment of regimen containing LZD.

Midkine expression is associated with clinicopathological features and BRAF mutation in papillary thyroid cancer

The objective of this study is to detect the expression of midkine (MK) in papillary thyroid cancer (PTC) and to evaluate whether MK expression is associated with clinicopathological features and BRAF mutation in PTC. The expression of MK in samples from 200 cases of PTC, 60 cases of adenomatoid nodule of thyroid, and 40 samples of tumor-adjacent normal thyroid tissue were assessed with immunohistochemistry. The BRAF mutation was detected by direct sequencing. The relationships between MK expression and the clinicopathological features of PTC and BRAF mutation were analyzed. The results demonstrated that MK was not expressed in tumor-adjacent normal tissue. The positive expression rates and MK scores were both higher in PTC than in adenomatoid nodule (positive expression rates: 88 vs. 8.3 %, P < 0.001; MK scores: 2.02 ± 0.93 vs. 0.08 ± 0.28, P < 0.001). The expression level of MK in PTC with extrathyroidal invasion, lymph node metastasis, or stage III/IV was significantly higher than that in PTC without such biological features (all P < 0.01). The overall prevalence of BRAF mutation was 66.5 % in PTC. The expression level of MK in PTC with BRAF mutation was significantly higher than that in PTC with wild-type BRAF (P < 0.001). We can conclude that MK is specifically expressed in PTC tissues and is associated with clinicopathological features and BRAF mutation. MK may be a helpful diagnostic and prognostic marker for PTC.

Expression of recombinant proteins in insect cells by their direct infection with Escherichia coli transformed with baculovirus bacmids

The baculovirus-insect cell expression system (BES), one of the most popular systems for expression of eukaryotic proteins, was known to have drawbacks such as laborious manipulation of large-size baculovirus bacmids and the transfection procedure. These problems could be eliminated by direct infection of eukaryotic cells with nonpathogenic bacteria harbouring the respective gene - bactofection. However, it was unknown whether this system could be applied to insect cells. Therefore, in this study, the possibility of delivery of enhanced green fluorescent protein (EGFP) gene as a marker into the insect cell lines Sf9 and BmN-SWU1 using the above-mentioned approach with the Bac-to-Bac system was investigated. Using a simple co-incubation of Escherichia coli strains containing recombinant baculovirus bacmids with the EGFP gene and insect cells, it was possible to demonstrate the EGFP expression in these cells and to obtain high-titer recombinant baculoviral stocks. Furthermore, BmN-SWU1 cells proved more susceptible to the used E. coli strains than Sf9 cells. However, the co-expression of invasin and listeriolysin-O, known to enhance the E. coli-mediated gene delivery to mammalian cells, with EGFP, had no effect on insect cells. Summing up, this study proved that a heterologous gene can be efficiently delivered and expressed in insect cells by their simple incubation with non-pathogenic E. coli strains harboring recombinant baculovirus bacmids with the respective gene.

A 12-week subchronic intramuscular toxicity study of risperidone-loaded microspheres in rats

Long-acting injectable formulations of antipsychotics have been an important treatment option to increase the compliance of the patient with schizophrenia by monitoring drug administration and identifying medication noncompliance and to improve the long-term management of schizophrenia. Risperidone, a serotoninergic 5-HT2 and dopaminergic D2 receptor antagonist, was developed to be a long-acting sustained-release formulation for the treatment of schizophrenia. In this study, 12-week subchronic toxicity study of risperidone-loaded microspheres (RMs) in rats by intramuscular injection with an 8-week recovery phase was carried out to investigate the potential subchronic toxicity of a novel long-acting sustained-release formulation. The results indicated that the dosage of 10-90 mg/kg of RM for 2 weeks did not cause treatment-related mortality. The main drug-related findings were contributed to the dopamine D2 receptor and α1-adrenoceptor antagonism of risperidone such as elevation of serum and pituitary prolactin levels and ptosis and changes in reproductive system (uterus, ovary, vagina, mammary gland, testis, seminal vesicle, epididymis, and prostate). In addition, foreign body granuloma in muscle at injection sites caused by poly-lactide-co-glycolide was observed. At the end of the recovery phase, these changes mostly returned to normal. The results indicated that RM had a good safety profile in rats.

TNF superfamily member TL1A elicits type 2 innate lymphoid cells at mucosal barriers

Immune responses at mucosal barriers are regulated by innate type 2 lymphoid cells (ILC2s) that elaborate effector cytokines interleukins 5 and 13 (IL5 and IL13). IL25 and IL33 are key cytokines that support ILC2s; however, mice deficient in these pathways retain some functional ILC2s. Analysis of human and murine cells revealed that ILC2s highly express tumor necrosis factor (TNF)-receptor superfamily member DR3 (TNFRSF25). Engagement of DR3 with cognate ligand TL1A promoted ILC2 expansion, survival, and function. Exogenous protein or genetic overexpression of TL1A activated ILC2s independent of IL25 or IL33. Dr3(-/-) mice failed to control gut helminthic infections, and failed to mount ILC2 responses in the lung after nasal challenge with papain. Our data demonstrate a key role for TL1A in promoting ILC2s at mucosal barriers.

Short-term effects of escitalopram on regional brain function in first-episode drug-naive patients with major depressive disorder assessed by resting-state functional magnetic resonance imaging

BACKGROUND

Most knowledge regarding the effects of antidepressant drugs is at the receptor level, distal from the nervous system effects that mediate their clinical efficacy. Using functional magnetic resonance imaging (fMRI), this study investigated the effects of escitalopram, a selective serotonin reuptake inhibitor (SSRI), on resting-state brain function in patients with major depressive disorder (MDD).

METHOD

Fourteen first-episode drug-naive MDD patients completed two fMRI scans before and after 8 weeks of escitalopram therapy. Scans were also acquired in 14 matched healthy subjects. Data were analyzed using the regional homogeneity (ReHo) approach.

RESULTS

Compared to controls, MDD patients before treatment demonstrated decreased ReHo in the frontal (right superior frontal gyrus), temporal (left middle and right inferior temporal gyri), parietal (right precuneus) and occipital (left superior occipital gyrus and right cuneus) cortices, and increased ReHo in the left dorsal medial prefrontal gyrus and left anterior lobe of the cerebellum. Compared to the unmedicated state, ReHo in the patients after treatment was decreased in the left dorsal medial prefrontal gyrus, the right insula and the bilateral thalamus, and increased in the right superior frontal gyrus. Compared to controls, patients after treatment displayed a ReHo decrease in the right precuneus and a ReHo increase in the left anterior lobe of the cerebellum.

CONCLUSIONS

Successful treatment with escitalopram may be associated with modulation of resting-state brain activity in regions within the fronto-limbic circuit. This study provides new insight into the effects of antidepressants on functional brain systems in MDD.

Normative reference of short-term heart rate variability and estimation of cardiovascular autonomic neuropathy prevalence in Chinese people

BACKGROUND

The cardiovascular autonomic neuropathy (CAN) prevalence is rapidly growing in all populations worldwide. This study aimed to evaluate the reference values for the short-term heart rate variable (HRV) and estimate CAN prevalence in our cross-sectional dataset.

METHODS

We conducted a large-scale, community-based, cross-sectional study in a Chinese population. Of 2,092 subjects available for data analysis, 371 healthy subjects were selected to reference the values for the short-term HRV. The short-term HRV analysis was performed for all subjects using a computer-aided examination and evaluation system for spectral analysis to investigate changes in autonomic regulation.

RESULTS

In the total sample, the reference value for total power was more than 356.13 ms(2). The cutoff points of 55.45 and 36.64 ms(2) were set for low frequency (LF) and high frequency (HF), respectively. The cutoff points of LFn and HFn were 6.40 and 4.83 ν, respectively. The normative reference of LF/HF ranged from 0.3 to 6.5. Using HRV test (model 1), the estimated age-adjusted CAN prevalence in the total sample was 16.83 %. The estimated age-adjusted CAN prevalence values were 31.07, 21.97 and 20.81 % in DM, HT, and MS patients, respectively.

CONCLUSION

Our findings provided reference values for short-term HRV. The estimated CAN prevalence was high in the Chinese population.

Clinical study of exercise on improvement of β-cell function and insulin resistance in non-diabetic young offsprings of diabetic patients

BACKGROUND

Previous studies have shown that exercise could improve β-cell function in humans or animal models of type 2 diabetes. However, whether it can prevent the progression of pre-diabetes to diabetes remains unclear.

AIM

To study the effects of exercise on glycolipid metabolism, β-cell function, and insulin resistance in the non-diabetic young offsprings of diabetic patients.

METHODS

One hundred and eighty-two normal glucose tolerance young offsprings of type 2 diabetic parents were enrolled. Individuals with fasting insulin ≥ 12.0 mU/L were assigned to hyperinsulinemia group (n = 72) and those with fasting insulin <12.0 mU/L were assigned to normal group (n = 110). The subjects in hyperinsulinemia group received 12-week exercise intervention. A 75-g oral glucose tolerance test and insulin release test were conducted before and after intervention. The area under curve of glucose (AUCglu), area under curve of insulin (AUCINS), HOMA insulin resistance index (HOMA-IR), HOMA β-cell function (HOMA-β), and early insulin secretion index (ΔI 30/ΔG 30) were calculated. Body composition was measured by dual energy X-ray absorptiometry.

RESULTS

At baseline, AUCINS and HOMA-β in hyperinsulinemia group were significantly higher compared with the normal group (P < 0.05). After the 12-week exercise intervention, no significant changes in blood pressure, body mass index, blood glucose, serum lipids, and percentage of body fat were found in hyperinsulinemia group; however, AUCINS, HOMA-β, HOMA-IR (P < 0.05) and ΔI 30/ΔG 30 (P < 0.01) were significantly decreased.

CONCLUSIONS

Exercise is effective for preventing pre-diabetic insulin resistance and β-cell dysfunction in non-diabetic young offsprings of diabetic patients.

Identification and characterization of the free fatty acid receptor 2 (FFA2) and a novel functional FFA2-like receptor (FFA2L) for short-chain fatty acids in pigs: evidence for the existence of a duplicated FFA2 gene (FFA2L) in some mammalian species

Free fatty acid receptor 2 (FFA2, also called GPR43) is reported to play a critical role in mediating the actions of short-chain fatty acids (SCFAs) in humans and mice. However, little is known about the structure, functionality, and tissue expression of FFA2 in other mammalian species, including pigs. In the present study, the full-length cDNAs of FFA2 (pFFA2) and a novel FFA2-like gene (named pFFA2L) were cloned from pig intestines by reverse transcription PCR. Both cloned pFFA2 and pFFA2L are predicted to encode 2 receptors of remarkable structural similarity and share high amino acid sequence identities with FFA2 from other mammalian species. Interestingly, the novel FFA2L could also be identified in 9 other mammalian species, suggesting that FFA2L was likely duplicated from FFA2 in the last common ancestor of these species. With the use of a pGL4-SRE-luciferase reporter assay, we demonstrated that pFFA2 expressed in human embryonic kidney 293 cells could be activated by acetate, propionate, and butyrate equipotently, whereas pFFA2L could be activated only by acetate and propionate, indicating that both pFFA2 and pFFA2L are functional receptors for SCFAs with nonidentical pharmacologic properties. Reverse transcription PCR found that pFFA2 mRNA was widely expressed in nearly all tissues examined, including adipose tissue and gastrointestinal (GI) tract, whereas pFFA2L expression was mainly restricted to the GI tract. Taken together, our findings raise a novel concept that the actions of SCFAs are likely mediated by 2 FFA2s (FFA2 and FFA2L) in target tissues of some mammalian species, such as the GI tract of pigs.

Genetic variants of 17q21 are associated with childhood-onset asthma and related phenotypes in a northeastern Han Chinese population: a case-control study

A genome-wide association study (GWAS) suggested that variants on chromosome 17q21 were associated with childhood-onset asthma in white populations. Two replication studies had been conducted in southern Han Chinese population in 2009 and 2012. However, these two Chinese replication results were inconsistent. To further confirm the role of 17q21 common variants, an association study of 17q21 single nucleotide polymorphisms (SNPs) with the risk of childhood-onset asthma was performed in a Han population from northeastern China. In this study, rs3894194, rs12603332 and rs11650680 were genotyped in 435 asthmatic children and 601 healthy controls by using a SNaPshot method. Our data showed that the allelic frequency of rs12603332 and rs11650680 showed significant differences between asthmatic cases and healthy controls, with an odds ratio (OR) of 1.36 [95% confidence interval (CI) 1.12-1.65, P=0.002] and an OR of 1.36 (95% CI 1.07-1.74, P=0.01). Genotype distribution analysis also showed the significant associations of the above two loci with childhood asthma under dominant, recessive and additive model (dominant OR=1.57, 95% CI 1.04-2.36, P=0.032; recessive OR=1.41, 95% CI 1.09-1.83, P=0.009; additive OR=1.97, 95% CI 1.24-3.14, P=0.004; recessive OR=1.50, 95% CI 1.13-1.98, P=0.005). Besides, linear regression analysis showed that rs3894194 and rs12603332 were also significantly associated with asthma phenotypes such as log10 -transformed immunoglobulin E (IgE) level (IU/ml) and log10 -transformed eosinophil percentage (dominant, P=0.04; additive, P=0.01; recessive, P=0.04; recessive, P=0.03; additive, P=0.02). Collectively, our findings suggest that orosomucoid 1-like 3 (ORMDL3) locus on chromosome 17q21 is a risk factor for childhood-onset asthma in northeastern Han Chinese population. Further studies will be needed to elucidate the pathogenesis that ORMDL3 locus predisposes to childhood-onset asthma.