[Effect of testicular puncture biopsy on the success rate of microdissection testicular sperm extraction for idiopathic non-obstructive azoospermia]

OBJECTIVE

To explore the predictive effect of testicular puncture biopsy and the biopsy results on the success rate of microdissection testicular sperm extraction (micro-TESE) in patients with idiopathic non-obstructive azoospermia.

METHODS

We retrospectively evaluated the micro-TESE performance in patients with idiopathic non-obstructive azoospermia (NOA) referred to the Reproductive Medicine Center of Peking University Third Hospital between January 2012 and August 2017. We discussed whether to take the testicular biopsy and testicular biopsy results, including the intraoperative microscopic examination and postoperative pathology findings, could predict the success rate of the late micro-TESE.

RESULTS

There were 237 patients who were diagnosed as idiopathic NOA and received micro-TESE involved in the study and the total sperm retrieve rate was 25.7%. In 103 patients without testicular biopsy and 134 patients with preoperative testicular biopsy, the sperm retrieve rate was 26.2% and 25.4%, respectively. And there was no significant difference between the two groups. The testicular volume and serum follicle stimulating hormone levels of the two groups were (4.3±1.4) mL vs.(8.5±2.4) mL and (36.1±5.2) IU/L vs.(26.1±3.5) IU/L, respectively. Compared to the patients with preoperative testicular biopsy, the group of patients without testicular biopsy had a much smaller test volume and higher serum follicle stimulating hormone and the difference between the two groups was statistically significant. For the patients who were found with a small amount of sperm in both intraoperative microscopic examination and postoperative pathological examination, the sperm retrieve rate was 100% (7/7). And for the patients who were only found with sperm in intraoperative microscopic examination or postoperative pathology examination, the sperm retrieve rate (SRR) was 47.2% (17/36). For the patients who could be not found with sperm in both intraoperative microscopic examination and postoperative pathological examination, the SRR was only 11% (10/91). The difference between the groups was statistically significant.

CONCLUSION

Idiopathic non-obstructive azoospermia patients with smaller testicular volume still have a chance to be found with sperm by micro-TESE. The testicular biopsy results, including intraoperative microscopic examination and postoperative pathological findings, have predictive effect on the SRR for late micro-TESE. The patient who could not be found with sperm in both intraoperative microscopic examination and postoperative pathological examination have a small chance of success in micro-TESE.

Dynamics in the Plastic Crystalline Phases of Cyclohexanol and Cyclooctanol Studied by Quasielastic Neutron Scattering

Plastic crystals are a promising candidate for solid state ionic conductors. In this work, quasielastic neutron scattering is employed to investigate the center of mass diffusive motions in two types of plastic crystalline cyclic alcohols: cyclohexanol and cyclooctanol. Two separate motions are observed which are attributed to long-range translational diffusion (α-process) and cage rattling (fast β-process). Residence times and diffusion coefficients are calculated for both processes, along with the confinement distances for the cage rattling. In addition, a binary mixture of these two materials is measured to understand how the dynamics change when a second type of molecule is added to the matrix. It is observed that, upon the addition of the larger cyclooctanol molecules into the cyclohexanol solution, the cage size decreases, which causes a decrease in the observed diffusion rates for both the α- and fast β-processes.

[Prevalence and influential factors of stroke in Jiangxi Province in 2014]

Objective: To discuss the prevalence and influential factors of stroke among population in Jiangxi Province. Methods: Four cities in urban areas and four counties in rural areas were selected firstly, in which two districts or townships were selected; and then three communities or villages were chosen from each district and township, respectively, using the simple random sampling (SRS) method. Finally 15 269 subjects aging 15 years old or above, living in Jiangxi Province ≥6 months were randomly selected to participate in this survey from November 2013 to August 2014. Information of population characteristics, life behavior way, individual disease history were collected through questionnaire survey, and height, weight, waist circumference, blood pressure, body fat rate, visceral fat index and so on were measured by instruments. Risk factors of stroke prevalence were analyzed by the unconditioned logistic regression analysis. Results: A total of 15 269 participants (6 267 males) from 15 364 eligible participants were included in the statistical analysis. Out of which, 7 793 participants came from urban areas, and their average age was (53.04±17.91) years old. In this study, 226 stroke patients (117 males) were found among15 269 participants, including 122 urban participants and 104 rural participants, whose average age was (67.76±9.74) years old. The prevalence of stroke was 1 480.12/100 000 in 2014, which was separately 1 866.92/100 000 and 1 210.84/100 000 among males and females. The prevalence of people aging (45-49) years old was 413.79/100 000 (6/1 450) , while which among people aging 75 years old and above was 3 311.62/100 000 (61/1 842) . The prevalence of stroke among residents in Jiangxi presented an uprising tendency with age increasing (linear-by-linear association χ(2)=62.23, P<0.01). The research showed that when other influencing factors including gender, BMI, waist circumference, pulse-pressure difference, VAI, and sleeping time in non-working days were controlled, hypertensive patients had a higher risk of stroke than people without hypertension (OR=6.88, 95%CI: 4.90-9.67), drinkers had a higher risk of stroke than non-drinkers (OR=1.56, 95%CI: 1.17-2.08), compared with people <65 years old, people aged 65-74 years old and ≥75 years old had a higher risk of stroke, the value of OR (95%CI) were 1.88 (1.36-2.59) and 1.97 (1.39-2.80), respectively, compared with people with normal body fat percentage, people whose body fat percentage on high side and people who with high body fat percentage had a higher risk of stroke, the value of OR (95%CI) were 1.71 (1.18-2.48) and 1.74 (1.18-2.56), respectively, people with sleep time >8 h had a higher risk of stroke than those with sleep time of 6-8 h. Conclusion: There was a high stroke prevalence among residents in Jiangxi province. Hypertension, drinking, age, BFP and sleep duration were associated with stroke prevalence. Corresponding measures for high-risk population and risk factors should be strengthened to prevent and control the stroke.

[Homocysteine induces calcium overload in neonatal rat atrial cells through activation of sodium current and CaMKⅡδ]

Objective: To investigate the effect and related mechanism of homocysteine (Hcy) on calcium overload in neonatal rat atrial cells (NRICs). Methods: NRICs were assigned to 9 groups after culture for 3 days: (1) control group; (2) Hcy group (0, 50, 100, 200, 500 μmol/L for 48 hours); (3) antioxidant group (NAC, 10 μmol/L for 24 hours); (4) Hcy+NAC group (500 μmol/L Hcy for 48 hours, then treated with 10 μmol/L NAC for 24 hours); (5) calcium/calmodulin dependent protein kinase Ⅱδ (CaMKⅡδ) inhibitor group (KN-93, 3 μmol/L KN-93 for 5 hours); (6) specific sodium current inhibitor group (ELE, 1 μmol/L ELE for 5 hours); (7) Hcy+KN-93 group (500 μmol/L Hcy for 48 hours, then treated with 3 μmol/L KN-93 for 5 hours); (8) Hcy+ELE group (500 μmol/L Hcy for 48 hours, then treated with 1 μmol/L ELE for 5 hours; (9) Hcy+KN-93+ELE group (500 μmol/L Hcy for 48 hours, then treated with 3 μmol/L KN-93 and 1 μmol/L ELE for 5 hours). Moreover, NRICs were also treated with CaMKⅡδ-siRNA lentivirus, and Nav1.5-siRNA lentivirus, negative lentivirus carrier containing green fluorescent protein (GFP) for 24 hours. The MOI values of the three groups were 10. Infection efficiency of lentivirus was determined by observing the percentage of GFP fluorescence under inverted fluorescence microscope after transfection for 24 hours, and cultured regularly with simultaneous Puro screening, then cells were grouped as Hcy+CaMKⅡδ-siRNA group, Hcy+Nav1.5-siRNA group and Hcy+negative group. The concentration of Ca(2+) in NRICs ([Ca(2+)]i) of various groups was detected through Fluo-4/AM fluorescence probe, then 2', 7'- two chlorofluorescein diacetate (DCFH-DA) was used as a probe to detect reactive oxygen species (ROS) in NRICs by flow cytometry. The malondialdehyde (MDA) was detected by the activity of superoxide dismutase (SOD) and xanthine oxidase was detected by thiobarbituric acid colorimetry. The protein and mRNA expression level of CaMKⅡδ and Nav1.5 in NRICs were detected by Western blot and quantitative real-time PCR. Results: (1) ROS, MDA and SOD were similar between NAC group and control group, ROS and MDA were significantly increased, while SOD was significantly reduced in Hcy group in a concentration-dependent manner. (2) [Ca(2+)]i: The level of [Ca(2+)]i was (155.57+7.25), (187.43+13.07), (248.98+27.22) and (307.36+15.09) nmol/L in 50, 100, 200 and 500 μmol/L Hcy groups, which was significantly higher than that in the control group ((123.18+7.24) nmol/L, P<0.01). In addition, the level of [Ca(2+)]i in Hcy+NAC group ((222.87+23.71)nmol/L) was significantly lower than that in Hcy 500 μmol/L group ((305.15+39.45) nmol/L, P<0.05), while [Ca(2+)]i level was similar between NAC group and the control group. (3) The protein expression of CaMKⅡδ and Nav1.5 was significantly upregulated in Hcy groups than in the control group. The protein expression level of CaMKⅡδ-Thr287 was significantly lower in NAC group than in Hcy 500 μmol/L group (P<0.01), however, there was no significant difference on the protein expression levels of CaMKⅡδ-Thr287 and Nav1.5 between NAC group and control group (all P>0.05). (4) The protein expression levels of CaMKⅡδ-Thr287 and the concentration of [Ca(2+)]i were significantly lower in Hcy+KN-93 group and Hcy+KN-93+ELE group than in Hcy 500 μmol/L group (P<0.05). [Ca(2+)]i concentration was significantly lower in Hcy+KN-93 group, Hcy+ELE group and KN-93+ELE+Hcy group than in Hcy 500 μmol/L group (P<0.05). (5) The mRNA and protein expression levels of CaMKⅡδ and Nav1.5 in each group infected with lentivirus: the GFP expression was ideal post lentivirus transfection for 24 hours (up to 90%), which was significantly lower in the CaMKⅡδ-siRNA group and Nav1.5-siRNA group than in the negative infection group (all P<0.05), which was similar between negative infection group and control group (P>0.05). Moreover, the mRNA and protein expression levels of CaMKⅡδ and CaMKⅡδ-Thr287 was significantly lower in Hcy+Nav1.5-siRNA group than in Hcy+negative infection group (P<0.05). The protein and mRNA levels of Nav1.5 were similar between Hcy+CaMKⅡδ-siRNA group and Hcy+negative infection group (P>0.05). Conclusions: Hcy can induce calcium overload in NRICs by increasing oxidative stress, upregulating the sodium channel protein, and activating the late sodium current and phosphorylating CaMKⅡδ.

[Long-term follow up experience of comprehensive treatment of testicular mixed germ cell tumors]

OBJECTIVE

Testicular mixed germ cell tumor is mixed with embryonal carcinoma, choriocarcinoma, yolk sac tumor, teratoma, seminoma and other two or more components of the testicular tumor, the clinical is relatively rare and high degree of malignancy, this article will summarize its clinical features and optimize its treatment.

METHODS

A retrospective analysis of the clinical data of 22 patients with testicular tumor mixed germ cell in Peking University Third Hospital from May 1994 to November 2016 was conducted using a combination of statistical analysis and discussion of the relevant literature.

RESULTS

The mean age of the 22 patients was (30.8±10.4) years and the rate of cryptorchidism was 13.6%. The maximum diameter of the tumor was (5.1±2.7 ) cm. The pathological results suggested that 12 cases (54.5%) contained two different germ cell tumor components, 7 cases (31.8%) contained 3 different tumor components, 2 cases (9.2%) contained 4 different tumor components, and 1 case (4.5%) contained 5 different tumor components. Tumor constituent analysis included yolk sac tumors(16 cases, 72.7%), mature teratoma (7 cases, 31.8%), immature teratoma (5 cases, 22.7%), embryonal carcinoma (17 cases, 77.3%) , choriocarcinoma (4 cases, 18.1%) and seminoma (6 cases, 27.3%). American Joint Committee of Cancer tumor staging indicated 19 cases of stage I a tumor, 2 cases of stage IIa tumor and 1 case of stage IIIa tumor. The mean values of human chorionic gonadotropin, alpha-fetoprotein and lactate dehydrogenase were 414.50 MIU/mL, 242.95 μg/L, 196.95 U/L (preoperative) and 17.20 MIU /mL, 90.20 μg/L, 183.70 U/L (postoperative within a year), and the comparison of the P values between the preoperative and the postoperative within a year were 0.079, 0.043 and 0.624. Fourteen patients underwent retroperitoneal lymph nodes dissection. Most patients lived with long-term survival (94.4%) after operation.

CONCLUSION

Comprehensive treatment of radical orchiectomy with retroperitoneal lymphadenectomy combined with necessary radiotherapy or chemotherapy might help to control the tumor and achieve long-term survival for most patients with testicular mixed germ cell tumor.

[Effect of different oxygen tension on the cytoskeleton remodeling of goat temporomandibular joint disc cells]

Objective The effect of different oxygen tensions on the cytoskeleton remodeling of goat temporomandibular joint (TMJ) disc cells were investigated. Methods Goat TMJ disc cells were cultured under normoxia (21% O₂) and hypoxia (2%, 4%, and 8% O₂). Toluidine blue, picrosirius red, and type Ⅰ collagen immunocytochemical staining were performed to observe the changes in cell phenotype under different oxygen levels. Immunofluorescent staining and real-time reverse transcription-polymerase chain reaction analysis were then performed to identify actin, tubulin, and vimentin in the cultured disc cells. Results TMJ disc cells still displayed fibroblast characteristics under different oxygen levels and their cytoskeletons had regular arrangement. The fluorescence intensities of actin and vimentin were lowest at 4% O₂(P<0.05), whereas that of tubulin was highest at 2% O₂ (P<0.05). No significant difference among the other groups was observed (P>0.05). Actin mRNA levels were considerably decreased at 2% O₂ and 4% O₂ in hypoxic conditions, while actin mRNA expression was highest in 21% O₂. Tubulin mRNA levels considerably increased at 2% O₂, while tubulin mRNA expression was lowest in 8% O₂ (P<0.05). Vimentin mRNA expression was lowest at 4% O₂ and highest at 21% O₂, and significant differences were observed between vimentin mRNA expression levels among these oxygen levels (P<0.05). Conclusion Cytoskeletons were reconstructed in different oxygen tensions, and 2% O₂ may be the optimal oxygen level required to proliferate TMJ disc cells.

Generation of Mesenchymal-Like Stem Cells From Urine in Pediatric Patients

OBJECTIVES

Mesenchymal stem cells (MSCs) have been widely used for regenerative medicine. Traditionally, the procedures of MSC isolation are usually invasive and time-consuming. Urine is merely a body waste, and recent studies have suggested that urine represents an alternative source of stem cells. We, therefore, determined whether the possibility of isolating mesenchymal-like stem cells was practical from human urine.

METHODS

A total of 16 urine samples were collected from pediatric patients. Urine-derived cells were isolated, expanded, and identified for specific cell surface markers using flow cytometry. Cell morphology was observed by microscopy. Osteogenic and adipogenic differentiation potential were determinded by culturing cells in specific induction medium, and assessed by alkaline phosphatase and oil red O stainings, respectively.

RESULTS

Clones were established and passaged successfully from primary cultures of urine cells. Cultured urine-derived cells at passage 3 were fusiform and arranged with certain directionality. Urine-derived cells at passage 5 displayed expressions of cell surface markers (CD29, CD105, CD166, CD90, and CD13). There was no expression of the general hematopoietic cell markers (CD45, CD34, and HLA-DR). Under in vitro induction conditions, urine-derived cells at passage 5 were able to differentiate into osteoblasts, but not adipocytes.

CONCLUSIONS

Urine may be a noninvasive source for mesenchymal-like stem cells. These cells could potentially provide a new source of autologous stem cells for regenerative medicine and cell therapy.

[Recurrent syncope related to catecholaminergic polymorphic ventricular tachycardia due to de novo RyR2-R2401H mutation]

Objective: To explore the clinical and molecular genetic features of a Chinese patient with catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods: Clinical data including resting electrocardiography, echocardiography and treadmill exercise testing of a patient with CPVT admitted to our department in March 2013 were analyzed, and the peripheral venous blood samples of the patient and his family members and 400 ethnicity-matched healthy controls were obtained. All exons and exon-intron boundaries of the six CPVT-related genes including RYR2, CASQ2, TRDN, CALM1, KCNJ2 and ANKB were sequenced to detect the variants related to CPVT. The relationship between the genotypes and phenotypes was analyzed to direct the target therapy. Results: Recurrent syncope induced either by exercise or extreme frightened fear was observed in this patient. There was no positive family history of syncope or sudden death. The resting electrocardiography and echocardiography of the patient were normal, while the exercise testing revealed bidirectional and polymorphic ventricular tachycardia. A cardiac ryanodine receptor gene mutation (R2401H) was identified in this patient, while this mutation was absent in his parents and sister and 400 controls. No variant was detected in the remaining five candidate genes. Treatment with high dose of metoprolol succinate (118.75 mg/d) was effective and patient was free of syncopal attack during the 2 years follow-up. Conclusion: This is the first report on RyR2-R2401H mutation in Chinese patient with CPVT, and high dose of metoptolol is the effective therapy option for CPVT related to RyR2 mutation.

Naltrexone/Bupropion extended release-induced weight loss is independent of nausea in subjects without diabetes

Naltrexone/bupropion extended release (NB) is indicated as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management in adults with an initial body mass index of ≥30 or ≥27 kg m(-2) and ≥1 weight-related comorbidity (e.g. hypertension, type 2 diabetes and dyslipidaemia). In phase 3 clinical studies, nausea occurred in significantly higher proportions of subjects randomized to NB vs. placebo (PBO). In this pooled analysis of three phase 3, 56-week, PBO-controlled studies, we characterized nausea and weight loss in NB- and PBO-treated subjects without diabetes. Subjects receiving NB (n = 1778) lost significantly more weight than those receiving PBO (n = 1160). Weight change was not significantly different between subjects reporting and not reporting nausea in either treatment arm. Severity of nausea was mild to moderate in ≥95% of all cases. In the NB arm, the highest incidence of nausea onset (9%) was reported during week 1. The median duration of mild, moderate and severe nausea in subjects receiving NB was 14, 9 and 13 days, respectively. Our results demonstrate that nausea associated with NB is rarely severe, primarily occurs early in treatment and is not a contributor to weight loss.

[Outcome of treatment of Y chromosome AZFc microdeletion patients]

OBJECTIVE

To discuss the treatment options for patients with azoospermia factor (AZF) c microdeletion on Y chromosome.

METHODS

One hundred and eighty three patients, who were diagnosed as AZFc microdeletion on Y chromosome in Peking University Third Hospital, were recruited in our study. In order to get better treatment option for this kind of patients, we retrospectively analyzed their clinic data including the treatment process and pregnancy outcome and found out the characteristics of their semen.

RESULTS

Among the 183 patients, sperms can be found in ejaculated semen in 105 patients (57.4%, 105/183). One hundred and three patients (98.1%, 103/105) were diagnosed as severe or extremely severe oligospermia. Regular medication was given to 98 patients, 6 patients (6.1%, 6/98) of which got natural pregnancy. The other 99 patients who have sperms in their semen received intracytoplasmic sperm injection (ICSI), 68 patients (68.7%, 68/99) of which got pregnancy. Seventy eight patients were diagnosed as azoospermia among all the 183 patients. Forty nine patients received testicular sperm aspiration (TESA), and 21 patients choose to receive micro-TESE directly. Among the 49 patients with TESA, sperms were retrieved in 17 patients (34.7%, 17/49), and sperms were not retrieved in 32 patients (65.3%, 32/49), of which 12 patients (37.5%, 12/32) gave up treatment and 20 patients (62.5%, 20/32) choose micro-TESE. Among the 41 patients who choose to receive micro-TESE, operation has been done on 19 patients, of which 11 patients (57.9%, 11/19) got sperms. Among the 11 patients, TESA has been done on 6 patients before micro-TESE, of which 4 patients (66.6%, 4/6) got sperms. ICSI has already been done on 7 azoospermia AZFc microdeletion patients who underwent micro-TESE, of which 4 patients (57.1%, 4/7) get pregnancy.

CONCLUSION

AZFc microdeletion patients who had sperms were always diagnosed as severe or extremely severe oligospermia. ICSI was their first choice instead of drug therapy. For AZFc microdeletion patients who were diagnosed as azoospermia, TESA was one of their choices, however, the success rate is not high. Micro-TESE is still possible to get sperms even after the failure of TESA. Therefore, we may choose micro-TESE instead of TESA in some azoospermia patients in order to reduce surgical trauma on patients.

[Outcome of treatment of Y chromosome AZFc microdeletion patients]

OBJECTIVE

To discuss the treatment options for patients with azoospermia factor (AZF) c microdeletion on Y chromosome.

METHODS

One hundred and eighty three patients, who were diagnosed as AZFc microdeletion on Y chromosome in Peking University Third Hospital, were recruited in our study. In order to get better treatment option for this kind of patients, we retrospectively analyzed their clinic data including the treatment process and pregnancy outcome and found out the characteristics of their semen.

RESULTS

Among the 183 patients, sperms can be found in ejaculated semen in 105 patients (57.4%, 105/183). One hundred and three patients (98.1%, 103/105) were diagnosed as severe or extremely severe oligospermia. Regular medication was given to 98 patients, 6 patients (6.1%, 6/98) of which got natural pregnancy. The other 99 patients who have sperms in their semen received intracytoplasmic sperm injection (ICSI), 68 patients (68.7%, 68/99) of which got pregnancy. Seventy eight patients were diagnosed as azoospermia among all the 183 patients. Forty nine patients received testicular sperm aspiration (TESA), and 21 patients choose to receive micro-TESE directly. Among the 49 patients with TESA, sperms were retrieved in 17 patients (34.7%, 17/49), and sperms were not retrieved in 32 patients (65.3%, 32/49), of which 12 patients (37.5%, 12/32) gave up treatment and 20 patients (62.5%, 20/32) choose micro-TESE. Among the 41 patients who choose to receive micro-TESE, operation has been done on 19 patients, of which 11 patients (57.9%, 11/19) got sperms. Among the 11 patients, TESA has been done on 6 patients before micro-TESE, of which 4 patients (66.6%, 4/6) got sperms. ICSI has already been done on 7 azoospermia AZFc microdeletion patients who underwent micro-TESE, of which 4 patients (57.1%, 4/7) get pregnancy.

CONCLUSION

AZFc microdeletion patients who had sperms were always diagnosed as severe or extremely severe oligospermia. ICSI was their first choice instead of drug therapy. For AZFc microdeletion patients who were diagnosed as azoospermia, TESA was one of their choices, however, the success rate is not high. Micro-TESE is still possible to get sperms even after the failure of TESA. Therefore, we may choose micro-TESE instead of TESA in some azoospermia patients in order to reduce surgical trauma on patients.

[Collagen structure and biomechanical properties of the goat temporomandibular joint disc]

OBJECTIVE

To establish objectively biomechanical criteria for temporomandibular joint disc tissue engineerings.

METHODS

Eight temporomandibular joint discs from a four-month-old goat were separated completely. A cylindrical sample with diameter of 3 mm in the anterior, intermediate, and posterior bands was obtained, and the samples underwent pre-compression test with three cycles under a speed of 0.025 mm · s⁻¹. With the end condition for the maximum load of less than 4.9 N and 1.5 mm compression displacement, the formal compression test was performed with the same speed. Moreover, this test obtained the stress-strain relationship and elastic modulus of each disc band. Ultrastructure and collagen fiber orientation of the district zone were observed by scanning electron microscope and polarized light microscope.

RESULTS

1) The physiological strain range of an articular disc was within 10%, and the quasilinear constitutive equation of articular disc tissues can be fitted with the polynomial function: y = ax + bx² + cx³. 2) The elastic modulus of the intermediate disc zone was the largest (P < 0.05). No significant difference existed between the anterior and posterior bands (P = 0.361). 3) Scanning electron microscope and polarized light microscope showed an annular disc collagen network structure, which was the internal part of the goat temporomandibular joint disc. The collagen arrangement of intermediate bands was tensely arranged anterior-posteriorly. The collagen of anterior and posterior bands went through mediolaterally with intersection of anterior-posterior branch fibersd.

CONCLUSION

Annular collagen network structure is the basis for goat temporomandibular joint disc compression resistance properties. The intermediate band demonstrated higher compression resistance performance than the anterior and posterior bands.

Relationship between epicardial adipose tissue volume and atrial fibrillation : A systematic review and meta-analysis

BACKGROUND

Several studies have suggested that epicardial adipose tissue (EAT) volume may be associated with the risk of atrial fibrillation (AF). However, these studies have reported conflicting results. We therefore aimed to investigate the relationship between EAT volume and AF.

METHODS

We systematically retrieved the relevant studies reporting on the relationship between EAT volume and AF using the Cochrane Library, PubMed, Medline, EBSCO, and Embase databases. Data were extracted from applicable articles, and mean differences were pooled using the RevMan 5.3 software.

RESULTS

Ten case-control studies were identified. With regard to the relationship between EAT volume and AF, both total-EAT volume (24.23 ml, 95 % CI: 19.40-29.06, p < 0.00001) and EAT volume surrounding the left atrium (LA-EAT; 16.35 ml, 95 %CI: 12.73-19.98, p < 0.00001) were significantly increased in patients with AF. With regard to the relationship between the different types of AF and EAT volume, there was a significant difference in the total-EAT volume subgroup (19.38 ml, 95 % CI: 11.45-27.31, p < 0.0001) and in the LA-EAT volume subgroup (17.91 ml, 95 % CI: 15.13-20.69, p < 0.00001) between patients with persistent AF (PeAF) and paroxysmal AF (PAF). However, there was no significant difference between the total-EAT and LA-EAT volume subgroups (χ (2)  = 0.12, p = 0.70).

CONCLUSION

EAT volume may be associated with an increased risk of AF. Additionally, the EAT volume in patients with PeAF was larger than that in PAF patients, independent of the location of EAT.

Controlling molecular ordering in solution-state conjugated polymers

Rationally encoding molecular interactions that can control the assembly structure and functional expression in a solution of conjugated polymers hold great potential for enabling optimal organic optoelectronic and sensory materials. In this work, we show that thermally-controlled and surfactant-guided assembly of water-soluble conjugated polymers in aqueous solution is a simple and effective strategy to generate optoelectronic materials with the desired molecular ordering. We have studied a conjugated polymer consisting of a hydrophobic thiophene backbone and hydrophilic, thermo-responsive ethylene oxide side groups, which shows a step-wise, multi-dimensional assembly in water. By incorporating the polymer into phase-segregated domains of an amphiphilic surfactant in solution, we demonstrate that both chain conformation and degree of molecular ordering of the conjugated polymer can be tuned in hexagonal, micellar and lamellar phases of the surfactant solution. The controlled molecular ordering in conjugated polymer assembly is demonstrated as a key factor determining the electronic interaction and optical function.

Correction: Controlling molecular ordering in solution-state conjugated polymers

Correction for 'Controlling molecular ordering in solution-state conjugated polymers' by J. Zhu et al., Nanoscale, 2015, DOI: 10.1039/c5nr02037a.

Trehalose decreases mutant SOD1 expression and alleviates motor deficiency in early but not end-stage amyotrophic lateral sclerosis in a SOD1-G93A mouse model

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder for which there is currently no effective treatment. Studies indicate that enhancing autophagy in mouse models of neurodegenerative disease can ameliorate the behavioral symptoms and pathological damage associated with the accumulation of pathological mutant proteins such as mutant superoxide dismutase (SOD1). This study investigated the effects of trehalose treatment on both early and end-stage disease in a transgenic mouse model of ALS via short-term (30 days after administration) and long-term (from 60 days after administration to death) trehalose treatment experiments. Sixty-day-old female SOD1-G93A transgenic mice were treated daily with 2% (w/v) trehalose in their drinking water for 30 days and monitored until they reached a neurological score of four, whereupon they were euthanized by cervical dislocation. Neurological, rotarod performance test and hanging wire test scores were recorded and body weight monitored. After death, the spinal cord was removed to assess the number of motor neurons and to measure the expression of mutant SOD1, LC3-II and p62. Trehalose significantly reduced the levels of mutant SOD1 and p62 and increased LC3-II in the spinal cords of 90-day-old SOD1-G93A transgenic mice. Furthermore, trehalose treatment significantly postponed disease onset, lengthened the time it took to reach a neurological score of 2 and preserved motor function; however, trehalose became less effective at delaying further disease progression as the disease progressed beyond a neurological score of 2 and it failed to extend the survival of SOD1-G93A transgenic mice. Additionally, independent of autophagy, trehalose consistently inhibited microgliosis and astrogliosis throughout the entire duration of the study. In conclusion, trehalose may be a useful add-on therapy in conjunction with other ALS treatment options to alleviate symptoms in early-stage ALS.

Inter-particle correlations in a hard-sphere colloidal suspension with polymer additives investigated by Spin Echo Small Angle Neutron Scattering (SESANS)

Using a neutron scattering technique that measures a statistically-averaged density correlation function in real space rather than the conventional reciprocal-space structure factor, we have measured correlations between poly(methyl-methacrylate) (PMMA) colloidal particles of several sizes suspended in decalin. The new method, called Spin Echo Small Angle Neutron Scattering (SESANS) provides accurate information about particle composition, including the degree of solvent penetration into the polymer brush grafted on to the PMMA spheres to prevent aggregation. It confirms for particles, between 85 nm and 150 nm in radius that inter-particle correlations closely follow the Percus-Yevick hard-sphere model when the colloidal volume-fraction is between 30% and 50% provided the volume-fraction is used as a fitted parameter. No particle aggregation occurs in these systems. When small amounts of polystyrene are added as a depletant to a concentrated suspension of PMMA particles, short-range clustering of the particles occurs and there is an increase in the frequency of near-neighbor contacts. Within a small range of depletant concentration, near-neighbor correlations saturate and large aggregates with power law density correlations are formed. SESANS clearly separates the short- and long-range correlations and shows that, in this case, the power-law correlations are visible for inter-particle distances larger than roughly two particle diameters. In some cases, aggregate sizes are within our measurement window, which can extend out to 16 microns in favorable cases. We discuss the advantages of SESANS for measurements of the structure of concentrated colloidal systems and conclude that the method offers several important advantages.

A rare loss-of-function SCN5A variant is associated with lidocaine-induced ventricular fibrillation

The human genome contains over 4 million variant sites, as compared to the reference genome, including rare sequence variants, which have the potential to exert large phenotypic effects, such as susceptibility to drug toxicity. We report identification and functional characterization of a rare non-synonymous (p.A1427S) variant in the SCN5A gene that was associated with incessant and lethal ventricular tachycardia and fibrillation after administration of lidocaine to a patient with acute myocardial infarction. The variant, located in a highly conserved domain distinct from the predicted lidocaine binding site, decreased peak current density of the sodium channel. With the increasing availability of the whole exome and whole genome sequencing data, it would be possible to identify and characterize rare variants in SCN5A that might predispose to lethal ventricular arrhythmias.

PCR screening reveals considerable unexploited biosynthetic potential of ansamycins and a mysterious family of AHBA-containing natural products in actinomycetes

AIMS

Ansamycins are a family of macrolactams that are synthesized by type I polyketide synthase (PKS) using 3-amino-5-hydroxybenzoic acid (AHBA) as the starter unit. Most members of the family have strong antimicrobial, antifungal, anticancer and/or antiviral activities. We aimed to discover new ansamycins and/or other AHBA-containing natural products from actinobacteria.

METHODS AND RESULTS

Through PCR screening of AHBA synthase gene, we identified 26 AHBA synthase gene-positive strains from 206 plant-associated actinomycetes (five positives) and 688 marine-derived actinomycetes (21 positives), representing a positive ratio of 2·4-3·1%. Twenty-five ansamycins, including eight new compounds, were isolated from six AHBA synthase gene-positive strains through TLC-guided fractionations followed by repeated column chromatography. To gain information about those potential ansamycin gene clusters whose products were unknown, seven strains with phylogenetically divergent AHBA synthase genes were subjected to fosmid library construction. Of the seven gene clusters we obtained, three show characteristics for typical ansamycin gene clusters, and other four, from Micromonospora spp., appear to lack the amide synthase gene, which is unusual for ansamycin biosynthesis. The gene composition of these four gene clusters suggests that they are involved in the biosynthesis of a new family of hybrid PK-NRP compounds containing AHBA substructure.

CONCLUSIONS

PCR screening of AHBA synthase is an efficient approach to discover novel ansamycins and other AHBA-containing natural products.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work demonstrates that the AHBA-based screening method is a useful approach for discovering novel ansamycins and other AHBA-containing natural products from new microbial resources.

Impaired natural killer cell-induced antibody-dependent cell-mediated cytotoxicity is associated with human immunodeficiency virus-1 disease progression

This study evaluates the correlation between natural killer (NK) cell function and human immunodeficiency virus (HIV)-1 disease progression in 133 untreated HIV-1 positive Chinese subjects, including 41 former plasma donors (FPDs) and 92 men who have sex with men, and 35 HIV-negative controls. Flow cytometry was used to determine the abundance of NK cell subsets, the expression levels of receptor species, human leucocyte antigen (HLA) genotyping and the antibody-dependent cell-mediated cytotoxicity (ADCC) responses of NK cells. We observed a decreased expression of CD56(dim) CD16(+) NK cell subsets and an increased expression of CD56(-) CD16(+) with HIV-1 infection. As well, the expression of activating and inhibitory receptors increased significantly in NK cells, but CD16 receptor levels and the NKG2A/NKG2C ratio were down-regulated with HIV-1 infection. ADCC responses were higher in elite controllers than in all other groups, and were correlated inversely with HIV-1 viral load but correlated positively with CD4 count only in FPDs. Furthermore, individuals infected for < 1 year have lower ADCC responses than those infected for > 1 year. We also observed a negative association between ADCC responses and viral load in those who carry the HLA-A*30/B*13/Cw*06 haplotype. The positive correlation between CD16 expression and ADCC responses and a negative correlation trend between CD158a and ADCC responses were also observed (P = 0·058). Our results showed that the ADCC response is associated with patients' disease status, receptor expression levels, infection time and specific HLA alleles, which indicates that ADCC may offer protective effects against HIV-1 infection.

Optical-Fiber Power Meter Comparison between NIST and KRISS

We describe the results of a comparison of reference standards between the National Institute of Standards and Technology (NIST-USA) and Korea Research Institute of Standards and Science (KRISS-R.O. Korea) for optical fiber-based power measurements at wavelengths of 1302 nm and 1546 nm. We compare the laboratories' reference standards by means of a temperature-controlled optical trap detector. Measurement results showed the largest difference of less than 2.5 parts in 10(3), which is within the combined standard (k=1) uncertainty for the two laboratories' reference standards.