Effect of annealing temperature on the structure of carbon encapsulated Fe3O4 nanospheres

Yolk–shell structured Fe₃O₄@C was obtained at 600 °C. A possible evolution mechanism of core–shell to yolk–shell Fe₃O₄@C is elaborated.

Density, structure, and strength of the distal radius in patients with psoriatic arthritis: the role of inflammation and cardiovascular risk factors

We investigated the densitometric and microstructural features of the distal radius in psoriatic arthritis (PsA) patients using high-resolution peripheral quantitative computed tomography. PsA patients have unique bone microstructural deficits, manifested as lower cortical bone density and higher cortical porosity, which are associated with a propensity to bone fragility.

INTRODUCTION

The aim of this study was to investigate the densitometric, geometric, microstructural, and biomechanical features of the distal radius in psoriatic arthritis (PsA) patients.

METHODS

This study cohort consisted of 53 PsA patients (24 males and 29 females), with an average age of 53.1 years and 53 gender- and age-matched controls. Areal bone mineral density (aBMD) of the hip, lumbar spine, and ultradistal radius was measured by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) was performed at the distal radius to obtain measures of volumetric BMD (vBMD), microstructure, and derived biomechanical indices.

RESULTS

There were no significant between-group differences in aBMD at the femoral neck, total hip, and ultradistal radius, while aBMD at the lumbar spine was significantly higher in patients. The only indices indicating compromised bone quality in PsA patients were related to cortical bone quality. Cortical vBMD were -3.8% significantly lower, while cortical pore volume, porosity index, and pore diameter were 108, 79.5, and 8.6%, respectively, significantly higher in patients. Cortical stress was marginally lower (-1.3%, p = 0.077) in patients with stress significantly more unevenly distributed (4.9%, p = 0.035). Endocortical perimeter and cortical pore volume were significantly higher in patients with vertebral fracture. Deficits in cortical bone quality were associated with indices of disease activity/severity and were more prominent in patients with type 2 diabetes mellitus or hypertension.

CONCLUSIONS

There is an intertwined relationship between chronic inflammation, cardiovascular risk factors, and bone loss in PsA. PsA patients seem to have unique bone microstructural deficits which are associated with a propensity to bone fragility.

De novo DNA methylation of the paternal genome in 2-cell mouse embryos

The developmental dynamics of DNA methylation events have been well studied. Active demethylation of the paternal genome occurs in the zygote, passive demethylation occurs during cleavage stages, and de novo methylation occurs by the blastocyst stage. It is believed that the paternal genome has lower levels of methylation during early development than the maternal genome. However, in this study, we provide direct and indirect evidence of genome-wide de novo DNA methylation of the paternal genome after the first cell cycle in mouse embryos. Although very little methylation was detected within the male pronucleus in zygotes, an intense methylation signal was clearly visible within the androgenetic 2-cell embryos. Moreover, the DNA methylation level of the paternal genome in the post-zygotic metaphase embryos was similar to that of the maternal genome. Using indirect immunofluorescence with an antibody to methylated lysine 9 in histone H3, we provided new evidence to support the concept of spatial compartmentalization of parental genomes in 2-cell mouse embryos. Nevertheless, the transient segregation of parental genomes was not observed by determining the DNA methylation distribution in the 2-cell embryos even though DNA methylation asymmetry between the maternal and paternal pronucleus existed in the 1-cell stage. The disappearance of separate immunofluorescence signals of 5-methyl cytosine in the 2-cell embryos might be attributed to the de novo methylation of the paternal genome during the first mitotic cycle.

Characteristics of spermatogonial stem cells derived from neonatal porcine testis

The aim of this study was to isolate and characterise porcine spermatogonial stem cells (PSSCs). The putative porcine germline stem cells from testis were isolated successfully by an improving way of enrichment with lymphocyte separation medium (LSM). Results from RT-PCR analyses showed that PSSCs were positive for OCT4, SOX2, NANOG, PGP9.5, c-MYC, KEL4 and PRDM-14 which are multipotent stem cell markers. At the protein level, the results of immunofluorescence analyses showed that PSSCs were positive for OCT4, PGP9.5, SOX2 and CD29. We successfully differentiated these PSSCs into adipocytes and muscle cells and then defined their characteristics, including morphology, surface stem cell markers, and mechanical properties. But the experiment of teratoma formation was negative. The results indicated the PSSCs could be multipotent. Atomic force microscopy was used to characterise the morphological and mechanical properties of undifferentiated PSSCs, as well as the differentiated adipocytes and muscle cells, which could be potentially useful for distinguishing PSSCs from differentiated cells.

Controlling the window size in mesoporous SBA-16

Dotted line: constant mean curvature with Im3̄m symmetry. Solid surface: electron density map of calcined SBA-16.

Expression of budding uninhibited by benzimidazoles-1 and mitotic arrest deficient-2 in endometrial carcinoma and its significance

OBJECTIVE

The aim of this study was to explore the expression of budding uninhibited by benzimidazoles-1 (Bub1) and mitotic arrest deficient-2 (Mad2) in endometrial carcinoma and its significance.

MATERIALS AND METHODS

The expression of Bub 1 and Mad2 in 30 human normal endometrial tissues (group A), 30 complexly-hyperplastic endometrial tissues (group B), and 63 endometrial carcinoma tissues (group C) was observed using immunohistochemistry (the streptavidin-peroxidase method).

RESULTS

The positive expression rates of Bub1 in groups A, B, and C were 86.67%, 56.67%, and 28.57%, respectively. The positive rate of Bub1 protein was correlated with the differentiation degree and clinical stage of endometrial carcinoma (p < 0.05) other than lymph node metastasis (p > 0.05): A higher differentiation degree and a more advanced stage of endometrial carcinoma indicated a higher positive rate of Bub1 protein. The positive rates of Mad2 protein in groups A, B, and C were 23.33%, 56.67%, and 85.71%, respectively. The positive rate of Mad2 protein was correlated with the differentiation degree of endometrial carcinoma (p < 0.05) other than its clinical stage and lymph node metastasis (p > 0.05): A lower differentiation degree indicated a higher positive rate of Mad2 protein. Bub1 and Mad2 proteins were negatively correlated in the endometrial carcinoma tissues (r = - 0.719, p < 0.001).

CONCLUSION

Bub1 and Mad2 proteins interact with each other. They may play an important role in the initiation and development of endometrial carcinoma.

Clinical analysis of 65 cases of laparoscopic treatments on tubal infertility caused by tubal distortion

OBJECTIVE

This study aims to investigate the clinical value of laparoscopic treatment on tubal infertility caused by tubal distortion.

MATERIALS AND METHODS

A total of 65 cases of patients with tubal infertility were divided into three groups based on tubal distortion degree, i.e., 21 cases had a minimum angle of tubal distortion < 45 degrees (A group), 39 cases had a distortion angle between 45 degrees and 90 degrees (B group), and five cases had a distortion angle between 90 degrees and 145 degrees (C group). The pregnancy outcome and the impact of tubal distortion degree on pregnancy outcome were analyzed 6 to 24 months after operation.

RESULTS

The total pregnancy rate of these 256 cases were 43.75% with an intrauterine pregnancy rate of 40.23% and an ectopic pregnancy rate of 3.52%. In the simple distortion tubal infertility cases, the total pregnancy rate was 44.62%. In Group A, five cases became pregnant after operation (33.33%); in Group B, 19 cases (48.72%); and in Group C, three cases (60%). The differences in pregnancy rate between Groups A and B and Groups A and C were statistically significant (p < 0.05), whereas that between Groups B and C was not (p > 0.05).

CONCLUSION

Tubal plastic surgery via laparoscopy is an effective way to treat infertility caused by tubal distortion by restoring the normal shape of oviducts, especially in cases when the minimum angle of tubal distortion is greater than 45 degrees.

In vitro and in vivo studies on biodegradable CaMgZnSrYb high-entropy bulk metallic glass

In order to enhance the corrosion resistance of the Ca65Mg15Zn20 bulk metallic glass, which has too fast a degradation rate for biomedical applications, we fabricated the Ca20Mg20Zn20Sr20Yb20 high-entropy bulk metallic glass because of the unique properties of high-entropy alloys. Our results showed that the mechanical properties and corrosion behavior were enhanced. The in vitro tests showed that the Ca20Mg20Zn20Sr20Yb20 high-entropy bulk metallic glass could stimulate the proliferation and differentiation of cultured osteoblasts. The in vivo animal tests showed that the Ca20Mg20Zn20Sr20Yb20 high-entropy bulk metallic glass did not show any obvious degradation after 4 weeks of implantation, and they can promote osteogenesis and new bone formation after 2 weeks of implantation. The improved mechanical properties and corrosion behavior can be attributed to the different chemical composition as well as the formation of a unique high-entropy atomic structure with a maximum degree of disorder.

Response characteristics of primary auditory cortex neurons underlying perceptual asymmetry of ramped and damped sounds

Sound envelope plays a crucial role in perception: ramped sounds (slow attack and quick decay) are louder in strength and longer in subjective duration than damped sounds (quick attack and slow decay) even if they are equal in intensity and physical duration. To explain the asymmetrical perception, the perceptual constancy hypothesis supposes that the listener eliminates the slow decay of damped sounds from the judgment of perception, while the persistence of perception hypothesis supposes asymmetrical neural responses after the source has stopped. To understand neural mechanisms underlying the perceptual asymmetry, we explored response properties of the primary auditory cortex (A1) neurons during ramped and damped stimuli in awake cats. We found two distinct types of cells tuned to specific features of the sound envelope: edge cells sensitive to the temporal edge, such as quick attack and decay, while slope cells sensitive to slow attack and decay. The former needs a short (<2.5 ms) period of stimulus duration for evoking maximal peak responses, while the latter needs a long (20 ms) period, suggesting that the timescale of processing underlies differential sensitivity between the cell types. The findings suggest that perceptual constancy is not yet be executed at A1 because the specific cells distinguishing the direction of amplitude change (attack or decay) are lacking in A1. On the other hand, there is evidence of persistence of perception: overall response duration during ramped sound reached 1.4 times longer than that during damped sound, originating mainly from the response asymmetry of the edge cell (sensitive to the quick decay of ramped sounds but not to the slow decay of damped sounds), and neuronal persistence of excitation after the termination of ramped sounds was substantially longer than that of damped sounds, corresponding to the psychological evidence of persistence of perception.

High-risk features in radiation-associated breast angiosarcomas

BACKGROUND

Radiation-associated breast angiosarcoma (RT-AS) is an uncommon malignancy with an incidence of less than 1 % of all soft tissue sarcomas. The overall prognosis is quite dismal with high rates of recurrences and poor overall survival. There is an obvious paucity of data regarding clinical outcomes of patients with breast RT-AS.

METHODS

We identified all patients with RT-AS treated at the Memorial Sloan-Kettering Cancer Center between 1982-2011 and collected their correlative clinical information.

RESULTS

We identified 79 women with RT-AS with a median age of 68 (range 36-87). The median interval between radiation and development of RT-AS was 7 years (range 3-19). The median time to local and distant recurrence was 1.29 years (95 % CI 0.72-NA) and 2.48 years (95 % CI 1.29-NA), respectively. The median disease-specific survival was 2.97 years (95 % CI 2.21-NA). Independent predictors of worse disease-specific survival included age 68 years (HR 3.11, 95 % CI 1.20-8.08, P=0.020) and deep tumors (HR 3.23, 95 % CI 1.02-10.21, P=0.046.)

CONCLUSION

RT-AS has high local/distant recurrence rates, limited duration on standard chemotherapy and poor disease-specific survival.