Abnormal white matter structural connectivity in treatment-naïve young adults with borderline personality disorder

OBJECTIVE

The pathogenesis of borderline personality disorder (BPD) is not well understood. We examined the microstructure of white matter in patients with BPD.

METHOD

Treatment-naïve young adult with BPD (N = 30) and young-adult healthy controls (HCs; N = 31) were subjected diffusion tensor imaging (DTI). Microstructural parameters were analyzed via tract-based spatial statistics (TBSS) and post hoc tractography.

RESULTS

TBSS analysis revealed that, relative to the HC group, the BPD group had significantly lower fractional anisotropy (FA) values in the genu and body of the corpus callosum (CC), right superior corona radiate, right anterior corona radiate, as well as higher radial diffusivity (RD) in the left anterior thalamic radiation. Tractography showed that FA values of fiber bundles passing through the fornix were significantly reduced in BPD group relative to HCs. No significant correlations were observed between clinical symptom and DTI indices in BPD group (FDR corrected).

CONCLUSION

Focal microstructural alterations were found in BPD group, mainly in the limbic system and CC. The present findings support the fronto-limbic disconnectivity hypothesis and suggest that abnormal maturation of white matter structures may play an important role in mechanism of BPD.

The conceptual design of interferometer/polarimeter system on HL-2M

HL-2M is a new medium-sized tokamak with major radius of 1.78 m, minor radius of 0.65 m, and aspect ratio of 2.8 and will be finished soon. In the conceptual design, a double-pass, horizontal view, multi-channel far-infrared (FIR) laser interferometer/polarimeter system (at 432 μm) is proposed to simultaneously measure the phase change and the Faraday rotation for density and current profile reconstruction. A vertical CO₂ dispersion interferometer system (with wavelength of 10.6 μm and 5.3 μm) is designed to measure the line density, which will mainly be used for density feedback. The performance of the system is expected to meet the requirement of the measurements on HL-2M, with phase accuracy ∼0.1°, time resolution ∼1 μs, spatial resolution ∼7.2 cm, and density measurement range of 1 × 10 ¹⁸-1 ×10²¹ m^-3.

Identification of a PRX variant in a Chinese family with congenital cataract by exome sequencing

BACKGROUND

Congenital cataract is a common cause of childhood vision impairment or blindness with genetic and clinical heterogeneity. The aim of this study was to identify the disease-associated gene in a Chinese family with congenital cataract.

METHODS

A four-generation Chinese family with three enrolled patients suffering from congenital cataract was studied. Detailed family history and clinical data of all the members were collected and recorded. Exome sequencing was applied in the proband to screen potential genetic variants, and then Sanger sequencing was used to verify the variant within the family.

RESULTS

A heterozygous variant, c.3673G > A (p.V1225M), in the periaxin gene (PRX) was identified in three patients and two asymptomatic individuals of the family. The variant was absent in the other three unaffected family members and in 3290 ethnically matched in-house controls from BGI-Shenzhen.

CONCLUSIONS

By utilizing both exome sequencing and Sanger sequencing, we identified a missense variant in the PRX gene that is possibly associated with disease in this family. Our finding may broaden the spectrum of genes associated with congenital cataract, and may provide insights into lens development, pathogenic mechanism, future clinical genetic diagnosis and therapy of congenital cataract.

Effects of subtle cognitive manipulations on placebo analgesia - An implicit priming study

Background

Expectancy is widely accepted as a key contributor to placebo effects. However, it is not known whether non‐conscious expectancies achieved through semantic priming may contribute to placebo analgesia. In this study, we investigated if an implicit priming procedure, where participants were unaware of the intended priming influence, affected placebo analgesia.

Methods

In a double‐blind experiment, healthy participants (n = 36) were randomized to different implicit priming types; one aimed at increasing positive expectations and one neutral control condition. First, pain calibration (thermal) and a credibility demonstration of the placebo analgesic device were performed. In a second step, an independent experimenter administered the priming task; Scrambled Sentence Test. Then, pain sensitivity was assessed while telling participants that the analgesic device was either turned on (placebo) or turned off (baseline). Pain responses were recorded on a 0–100 Numeric Response Scale.

Results

Overall, there was a significant placebo effect (p < 0.001), however, the priming conditions (positive/neutral) did not lead to differences in placebo outcome. Prior experience of pain relief (during initial pain testing) correlated significantly with placebo analgesia (p < 0.001) and explained 34% of placebo variance. Trait neuroticism correlated positively with placebo analgesia (p < 0.05) and explained 21% of placebo variance.

Conclusions

Priming is one of many ways to influence behaviour, and non‐conscious activation of positive expectations could theoretically affect placebo analgesia. Yet, we found no SST priming effect on placebo analgesia. Instead, our data point to the significance of prior experience of pain relief, trait neuroticism and social interaction with the treating clinician.

Significance

Our findings challenge the role of semantic priming as a behavioural modifier that may shape expectations of pain relief, and affect placebo analgesia.

Rate dependent of strength in metallic glasses at different temperatures

The correlation between the strength at the macroscale and the elastic deformation as well as shear cracking behavior at the microscale of bulk metallic glasses (BMGs) is investigated. The temperatures of 298 K and 77 K as well as the strain rate ranging from 10⁻⁶ s⁻¹ to 10⁻² s⁻¹ are applied to the BMGs, in which the mechanical responses of the BMGs are profiled through the compression tests. The yield strength is associated with the activation of the elementary deformation unit, which is insensitive to the strain rate. The maximum compressive strength is linked to the crack propagation during shear fracture process, which is influenced by the strain rate. The cryogenic temperature of 77 K significantly improves the yield strength and the maximum compressive strength of the BMGs.

Anorexia is Associated with Stress-Dependent Orexigenic Responses to Exogenous Neuropeptide Y

Chicken lines that have been divergently selected for either low (LWS) or high (HWS) body weight at 56 days of age for more than 57 generations have different feeding behaviours in response to a range of i.c.v. injected neurotransmitters. The LWS have different severities of anorexia, whereas the HWS become obese. Previously, we demonstrated that LWS chicks did not respond, whereas HWS chicks increased food intake, after central injection of neuropeptide Y (NPY). The present study aimed to determine the molecular mechanisms underlying the loss of orexigenic function of NPY in LWS. Chicks were divided into four groups: stressed LWS and HWS on day of hatch, and control LWS and HWS. The stressor was a combination of food deprivation and cold exposure. On day 5 post-hatch, each chick received an i.c.v. injection of vehicle or 0.2 nmol of NPY. Only the LWS stressed group did not increase food intake in response to i.c.v. NPY. Hypothalamic mRNA abundance of appetite-associated factors was measured at 1 h post-injection. Interactions of genetic line, stress and NPY treatment were observed for the mRNA abundance of agouti-related peptide (AgRP) and synaptotagmin 1 (SYT1). Intracerebroventricular injection of NPY decreased and increased AgRP and SYT1 mRNA, respectively, in the stressed LWS and increased AgRP mRNA in stressed HWS chicks. Stress was associated with increased NPY, orexin receptor 2, corticotrophin-releasing factor receptor 1, melanocortin receptor 3 (MC3R) and growth hormone secretagogue receptor expression. In conclusion, the loss of responsiveness to exogenous NPY in stressed LWS chicks may be a result of the decreased and increased hypothalamic expression of AgRP and MC3R, respectively. This may induce an intensification of anorexigenic melanocortin signalling pathways in LWS chicks that block the orexigenic effect of exogenous NPY. These results provide insights onto the anorexic condition across species, and especially for forms of inducible anorexia such as human anorexia nervosa.

[Postoperative analgesia effect of different background volumes of ropivacaine in continuous tibial nerve block in patients with calcaneal surgery]

OBJECTIVE

To observe the clinical effect of different background volumes of ropivacaine in continuous tibial nerve block of postoperative analgesia after calcaneal surgery.

METHODS

This study was a prospective, randomized, controlled study. Sixty cases of calcaneal visual analogue scale (ASA) I or II undergoing elective surgery were selected and randomly assigned to two groups, thirty cases in each group. The patients received popliteal fossa posterior tibial nerve block using ultrasound guided. The continuous stimulation catheter was inserted after successful position and the 0.2% ropivacaine was injected. The background volumes of the A and B groups were 5 mL/h and 3.2 mL/h. The VAS score, the sensory block and motor block of tibial nerve and common peroneal nerve, and the satisfaction of the patients at h 12, h 24 and h 48 were recorded after catheter insertion.

RESULTS

The VAS scores at the three time points (h 12, h 24 and h 48) on the two groups of the patients were compared, and the difference was not statistically significant (P > 0.05). The difference of the sensory block and the motor block of the tibial nerve at the three time points (h 12, h 24 and h 48) on the two groups of the patients were also compared, and the difference was not statistically significant (P> 0.05). The difference of the sensory block and the motor block of common peroneal nerve at h 48 hs was statistically significant, group A was higher than the group B (P< 0.05). The difference of the patient satisfaction at the three time points (h 12, h 24 and h 48) on the two groups was not statistically significant (P> 0.05).

CONCLUSION

The use of 0.2% ropivacaine with the background volume of 3.2 mL/h in continuous tibial nerve block can provide good analgesia and reduce the incidence of the sensory block and motor block of the common peroneal nerve.

A longitudinally split rabbit segmental gracilis to simulate penile erectile function: anatomic basis and animal models

OBJECTIVE

The gracilis was once applied in reconstructing erectile function but its appearance was bulky. We aimed to design a model meeting the requirements of both reducing volume and retaining function.

MATERIALS AND METHODS

The gracilis muscles of 6 rabbits were harvested, applied colorful vascular perfusion and modified Sihler's intramuscular nerve staining. According to their intramuscular nerves and blood vessels, 9 rabbit right gracilis muscles were then longitudinally split into two halves. The anterior muscle bundle was selected as the functional unit and blood supply.

RESULTS

The intramuscular nerves and vessels were simultaneously presented on a same specimen. Their relationship suggested gracilis muscle to be composed of two relatively independent subunits. The reconstructed penis survived well, simulating erectile action satisfactorily.

DISCUSSION

The penis model reconstructed with longitudinally split rabbit segmental gracilis myocutaneous flap had met the requirements of both restoring erectile function and improving the appearance.

Abnormalities of cortical structures in adolescent-onset conduct disorder

BACKGROUND

Converging evidence has revealed both functional and structural abnormalities in adolescents with early-onset conduct disorder (EO-CD). The neurological abnormalities underlying EO-CD may be different from that of adolescent-onset conduct disorder (AO-CD) patients. However, the cortical structure in AO-CD patients remains largely unknown. The aim of the present study was to investigate the cortical alterations in AO-CD patients.

METHOD

We investigated T1-weighted brain images from AO-CD patients and age-, gender- and intelligence quotient-matched controls. Cortical structures including thickness, folding and surface area were measured using the surface-based morphometric method. Furthermore, we assessed impulsivity and antisocial symptoms using the Barratt Impulsiveness Scale (BIS) and the Antisocial Process Screening Device (APSD).

RESULTS

Compared with the controls, we found significant cortical thinning in the paralimbic system in AO-CD patients. For the first time, we observed cortical thinning in the precuneus/posterior cingulate cortex (PCC) in AO-CD patients which has not been reported in EO-CD patients. Prominent folding abnormalities were found in the paralimbic structures and frontal cortex while diminished surface areas were shown in the precentral and inferior temporal cortex. Furthermore, cortical thickness of the paralimbic structures was found to be negatively correlated with impulsivity and antisocial behaviors measured by the BIS and APSD, respectively.

CONCLUSIONS

The present study indicates that AO-CD is characterized by cortical structural abnormalities in the paralimbic system, and, in particular, we highlight the potential role of deficient structures including the precuneus and PCC in the etiology of AO-CD.

Uterine microvascular sensitivity to nanomaterial inhalation: An in vivo assessment

With the tremendous number and diverse applications of engineered nanomaterials incorporated in daily human activity, exposure can no longer be solely confined to occupational exposures of healthy male models. Cardiovascular and endothelial cell dysfunction have been established using in vitro and in situ preparations, but the translation to intact in vivo models is limited. Intravital microscopy has been used extensively to understand microvascular physiology while maintaining in vivo neurogenic, humoral, and myogenic control. However, a tissue specific model to assess the influences of nanomaterial exposure on female reproductive health has not been fully elucidated. Female Sprague Dawley (SD) rats were exposed to nano-TiO2 aerosols (171 ± 6 nm, 10.1 ± 0.39 mg/m(3), 5h) 24-hours prior to experimentation, leading to a calculated deposition of 42.0 ± 1.65 μg. After verifying estrus status, vital signs were monitored and the right horn of the uterus was exteriorized, gently secured over an optical pedestal, and enclosed in a warmed tissue bath using intravital microscopy techniques. After equilibration, significantly higher leukocyte-endothelium interactions were recorded in the exposed group. Arteriolar responsiveness was assessed using ionophoretically applied agents: muscarinic agonist acetylcholine (0.025 M; ACh; 20, 40, 100, and 200 nA), and nitric oxide donor sodium nitroprusside (0.05 M; SNP; 20, 40, and 100 nA), or adrenergic agonist phenylephrine (0.05 M; PE; 20, 40, and 100 nA) using glass micropipettes. Passive diameter was established by tissue superfusion with 10(-4)M adenosine. Similar to male counterparts, female SD rats present systemic microvascular dysfunction; however the ramifications associated with female health and reproduction have yet to be elucidated.

MicroRNA-155 Deficiency Suppresses Th17 Cell Differentiation and Improves Locomotor Recovery after Spinal Cord Injury

Spinal cord injury (SCI) is considered to be primarily associated with loss of motor function and leads to activate diverse cellular mechanisms in the central nervous system to attempt to repair the damaged spinal cord tissue. Mir-155 has been reported to be involved in both innate and adaptive immune responses. But the role of Mir-155 in spinal cord injury is still unknown. In our current study, Mir-155 deficiency displays increased myelin sparring and enhanced SC repair process. The number of T cells, B cells and neutrophils are all significantly lower in Mir-155(-/-) group than that in WT group after SCI. IL-17A-producing cells and the expression of IL-17A are markedly lower in Mir-155(-/-) mice than that in WT mice. We also found higher production of IL-17 by WT CD4(+) T cells than Mir-155(-/-) CD4(+) T cells in vitro. In our further DC-T cell coculture system, Mir-155 deficiency in DCs results in significantly less IL-17 production from T cells. Furthermore, the inhibited Th17 differentiation induced by Mir-155 deficiency is partly dependent on increased expression of SOCS1. In conclusion, our present work provides evidence to support the concept that Mir-155 deficiency suppresses Th17 cell differentiation and improves locomotor recovery after SCI.