Chemical composition and antioxidant activity of Polygonatum kingianum processed by the traditional method of "Nine Cycles of Steaming and Sun-Drying"

Polygonatum kingianum Coll. et (Hemsl) is a famous Chinese traditional food and medicine analogous plant. The rhizome of P. kingianum showed a decrease in levels of alkaloids, amino acids and derivatives, terpenoids, and an increase in organic acid and saccharides when it was processed by the traditional method of "Nine Cycles of Steaming and Sun-Drying". The relative content of 341 metabolites were increased (fold change, FC > 2; variable importance in projection, VIP > 1 and P-value, P < 0.05); while 456 metabolites were decreased (FC < 0.5, VIP > 1, and P < 0.05). The changes in chemical components result in a decrease in numb taste and an increase in sweetness. The increased antioxidant activity was observed in the processed samples. Together, this work has advanced the mechanism of reducing numb taste and enhancing antioxidant activity in the resource plants, such as P. kingianum, processed by the traditional method.

A study on serum pro-neurotensin (PNT), furin, and zinc alpha-2-glycoprotein (ZAG) levels in patients with acromegaly

PURPOSE

Acromegaly caused by growth hormone cell adenoma is commonly associated with abnormal glucolipid metabolism, which may result from changes in adipocytokine secretion. This study aims to investigate serum adipokine levels, including pro-neurotensin (PNT), furin, and zinc alpha-2-glycoprotein (ZAG), in acromegalic patients and the correlation between the levels of these three adipokines and GH levels and glucolipid metabolism indices.

METHODS

Sixty-eight acromegalic patients and 121 controls were included, and their clinical data were recorded from electronic medical record system. Serum PNT, furin and ZAG levels were measured by ELISA.

RESULTS

Serum PNT levels in acromegalic patients were significantly higher than controls (66.60 ± 12.36 vs. 46.68 ± 20.54 pg/ml, P < 0.001), and acromegaly was an independent influencing factor of PNT levels (P < 0.001). Moreover, subjects with the highest tertile of PNT levels had a close correlation with acromegaly (OR = 22.200, 95% CI 7.156 ~ 68.875, P < 0.001), even in Model 1 adjusted for gender and age and Model 2 adjusted for gender, age and BMI. Additionally, serum PNT levels were positively correlated with BMI (r = 0.220, P = 0.002) and triglycerides (TGs, r = 0.295, P < 0.001), and TGs were an independent influencing factor of serum PNT levels in acromegalic subjects (P < 0.001). Furthermore, serum PNT levels in obese acromegalic patients were significantly higher than those with normal BMI (P < 0.05). However, serum furin levels were lower in acromegalic patients than controls (0.184 ± 0.036 vs. 0.204 ± 0.061 ng/ml, P < 0.001).

CONCLUSION

This study is the first to demonstrate that acromegalic patients have increased serum PNT levels. Moreover, serum PNT plays a potential role in abnormal lipid metabolism of acromegalic patients.

Bone microarchitecture impairment in prolactinoma patients assessed by HR-pQCT

PURPOSE

Prolactinoma may reduce bone mineral density (BMD) and increase fracture risk, but its influence on bone microarchitecture remains to be elucidated. The purpose of this study is to evaluate bone microarchitecture parameters by high-resolution peripheral quantitative computed tomography (HR-pQCT) in prolactinoma patients.

METHODS

31 prolactinoma patients and 62 age- and sex-matched healthy controls in our center were included, and HR-pQCT was used to evaluate their bone microarchitecture at the radius and tibia. Z-scores for bone microarchitecture parameters were calculated based on previously published reference.

RESULTS

After adjusting for height and weight, prolactinoma patients had lower trabecular (- 0.011 mm, p = 0.005) and cortical thickness (- 0.116 mm, p = 0.008) and cortical area (- 6.0 mm2, p = 0.013) at radius, as well as lower trabecular (- 0.014 mm, p = 0.008) and cortical (- 0.122 mm, p = 0.022) thickness at tibia compared with the controls. Patients with higher prolactin level had more severe bone microarchitecture impairments. After adjusting for prolactin level and age, male patients had lower trabecular volumetric BMD (vBMD), trabecular number, trabecular thickness, and cortical porosity at radius, as well as lower trabecular vBMD, trabecular bone volume fraction, trabecular number, and cortical area, and higher trabecular separation at tibia compared with female patients. Z-score for radius vBMD was correlated with Z-score for areal BMD (aBMD) at lumbar and femoral neck, while Z-score for tibia vBMD was correlated with Z-score for lumbar aBMD, and some patients with vBMD Z-score below - 2.0 had aBMD Z-score within normal range.

CONCLUSION

Peripheral bone microarchitecture was impaired in prolactinoma patients, especially in patients with higher prolactin level. We compared the bone microarchitecture of prolactinoma patients and healthy controls by high-resolution peripheral quantitative computed tomography (HR-pQCT), and found that many bone microarchitecture parameters were impaired among prolactinoma patients. Such impairment was more prominent among patients with higher prolactin level.

P-676 Comparison of hCG triggering versus hCG in combination with a GnRH agonist: a prospective randomized controlled trial

Study question

Does co-administration of GnRH agonist and Human chorionic gonadotropin(dual trigger) in PGT cycles improve the number of usable blastocysts per patient compared to hCG alone?

Summary answer

Using the dual trigger has no effect on the number of usable blastocysts undergoing the GnRH-ant protocol for PGT compared to triggering with hCG alone.

What is known already

HCG is used at the end of controlled ovarian hyperstimulation as a surrogate LH surge to induce final oocyte maturation. Recently, based on retrospective studies, the co-administration of GnRH agonist and hCG for final oocyte maturation (dual trigger) has been suggested to improve IVF outcome and pregnancy rates.

Study design, size, duration

A prospective, randomized, open-label controlled clinical trial (ChiCTR-ICR-2000031342), enrolled patients attending our university affiliated Infertility and IVF center (the Reproductive and Genetic Hospital of CITIC-Xiangya, China) between August 2020 and June 2021. This sample size achieves with a power of 80%, at a significance level(α) of 0.05. A sample size of 160 patients, 80 randomized to each group, was chosen to allow for those 10% dropped out.

Participants/materials, setting, methods

The inclusion criteria for participating were: women age 20–35years, AMH≥1.2ng/ml and /or AFC ≥5, Couples with PGT-SR preimplantation genetic testing for chromosomal structural rearrangements (patients with abnormal chromosomal structure only in male or female), undergoing one of their first PGT cycle attempts. Patients fulfilled the criteria on the trigger day were randomly assigned to receive hCG or the dual trigger for final oocyte maturation. The primary outcome was the number of usable blastocysts per patient.

Main results and the role of chance

160 patients were included in the study. The age (29.1 years versus 29.4 years), BMI (22.1 kg/m2 versus 21.9 kg/m2) and the AMH (5.3 ng/ml versus 5.3 ng/ml) were comparable between the two groups. Based on PP analysis, there were no statistical difference in the number of eggs retrieved (17.1 versus 15.9), the MII oocytes (13.3 versus 12.5), the number of usable blastocysts per patient (5.0 versus 4.6) and top-quality blastocysts per patient (3.4 versus 3.2) between the two groups.

Limitations, reasons for caution

None

Wider implications of the findings

The enhanced response observed with the dual trigger might lead to better IVF outcomes were it used more widely.

Trial registration number

ChiCTR-ICR-2000031342

P-407 Pregnancy outcomes of different endometrial preparation in patients with a history of cesarean section

Study question

To investigate the efficacies of three cycle regimens in women receiving frozen embryo transfer with a history of cesarean section(CS).

Summary answer

In women undergoing frozen embryo transfer with a history of CS, hormone replacement therapy for endometrial preparation was associated with a higher early miscarriage rate.

What is known already

Rates of CS are rising worldwide. Many women with a history of a CS delivery conceived through assisted reproductive technology (ART) are in need of frozen embryo transfer (FET) for their second progeny. Various protocols for endometrium preparation have been used to provide an optimal uterine environment for the transfer of thawed embryos, but the evidence supporting the superiority of one protocol over another is insufficient.

Study design, size, duration

A retrospective cohort study of patients (N = 6,159) with a history of CS who fulfilled the inclusion criteria were enrolled in the study from January 2014 to December 2019 at the CITIC-Xiangya Hospital of Reproduction and Genetics.

Participants/materials, setting, methods

Reproductive outcomes of patients in the natural cycle （NC） (n = 4,306) versus hormone replacement therapy（HRT） (n = 1,007) versus gonadotropin-releasing hormone agonist （GnRH-a） + HRT groups (n = 846) were compared. Multiple logistic regression analyses were performed to investigate the potential confounding factors.

Main results and the role of chance

The unadjusted odds of the miscarriage rate of singleton pregnancies were also significantly higher in the hormone replacement therapy compared with the natural cycle (25.5% versus 20.4%, respectively). After adjusting for possible confounding factors, the early miscarriage rate and the miscarriage rate of singleton pregnancies remained significantly higher in the hormone replacement therapy than the natural cycle. The clinical pregnancy rates in the hormone replacement therapy, hormone replacement therapy and treatment with gonadotropin-releasing hormone agonist of women with a history of cesarean section was 48.8%, 48% and 47.1%, respectively, and the live birth rates were 37%, 34.1% and 35.7%, respectively.

Limitations, reasons for caution

This study is limited by its retrospective design. Furthermore, the detailed ultrasound information on uterine myometrial defects, complications related to CS and the number of previous CSs were unavailable in our study. Another limitation is that pregnancy-related complications and neonatal outcomes were not analyzed.

Wider implications of the findings

Our study could help physicians improve their understanding of the impact of different protocols on pregnancy outcomes in patients with a history of CS. Prospective randomized trials should be conducted to assess the efficacy of endometrial preparation protocols for FET in women with a history of CS.

Trial registration number

not applicable

P-060 Bubble-shaped Acrosome: Novel phenotype of Teratozoospermia Caused by Mutation in Actin-like 7A

Study question

What’s the etiology of severe teratozoospermia characteristic as bubble-shaped acrosome (BSA)?

Summary answer

Severe teratozoospermia characterized as BSA caused by mutation (c.1024G&gt;A) in actin-like 7A (ACTL7A).

What is known already

Teratozoospermia is a common cause of male infertility, defined by having a proportion of morphologically normal sperm at less than 4%. It exhibits aberrant sperm phenotypes in the head, neck, midpiece, and endpiece of sperm. Teratozoospermia with ephalic abnormalities are among the most severe and characteristic sperm defects. Some genetic factors are reported to be associated with ephalic abnormalities such as globozoospermia and macrozoospermia. However, other phenotypes and the causative genes of ephalic abnormalities, especially in acrosomal structure, and were largely unknown.

Study design, size, duration

Severe teratozoospermia were recruited from the Reproductive and Genetic Hospital of CITIC-Xiangya from Jan 2019 to Dec 2021.

Participants/materials, setting, methods

Whole-exome sequencing analysis was used to analyze the genetic factor of man. An Actl7a-mutated mouse model was generated by CRISPER-Cas9. Transmission electron microscopy was used to detect the abnormality of ultrastructure during acrosome biogenesis. Immunostaining was used to analyze the localization of ACTL7A and PLCζ. Immunoprecipitation followed by liquid chromatography-mass spectrometry (LC-MS) was used to select the differentially expressed proteins. ICSI with calcium ionophore exposure was performed in couple with ACTL7A mutation.

Main results and the role of chance

We found a man with severe teratozoospermia characterized as BSA carrying a mutation (c.1024G&gt;A) in ACTL7A. Homozygous Actl7a-mutated male mice were sterile, and all of sperm showed acrosomal abnormalities. During acrosomal biogenesis, it detected the acrosome detach from the nuclear in Actl7a-mutated mice. Furthermore, mutant ACTL7A failed to attach to the acroplaxome and was discharged by cytoplasmic droplets, which led to the absence of ACTL7A in mature sperm. The mutant sperm failed to activate the oocyte, and PLCζ discharge accompanied by ACTL7A was observed, leading to total fertilization failure (TFF). Immunoprecipitation followed by LC-MS showed that several differentially expressed proteins participate in acrosome assembly and actin filament organization. Furthermore, assisted oocyte activation by calcium ionophore exposure successfully overcame TFF in a couple with an ACTL7A mutation.

Limitations, reasons for caution

More cases are needed to demonstrate the relationship between mutation and phenotype.

Wider implications of the findings

Our study defined a novel phenotype of the acrosomal abnormality characterized as BSA and revealed the underlying mechanism of mutation in ACTL7A and provided a genetic marker and a therapeutic option for male infertility.

Trial registration number

Not Applicable

Pregnancy outcome after in-vitro fertilization/intracytoplasmic sperm injection in women with congenital uterus didelphys

OBJECTIVE

To investigate the pregnancy and obstetric outcomes of patients with congenital uterus didelphys who achieved clinical pregnancy after in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

METHODS

This was a retrospective matched-cohort study of 83 infertile patients with uterus didelphys who underwent IVF/ICSI and achieved clinical pregnancy from January 2005 to December 2018 at our center. For each patient in the study group, three control patients with normal uterine morphology who underwent IVF/ICSI in 2018 were selected randomly. Patients in the two groups were matched for number of gestational sacs, maternal age, infertility type, cause of infertility, fertilization method, endometrial thickness 1 day before embryo transfer and number of embryos transferred. The classification of congenital uterine anomalies was based on the American Fertility Society system (1988). The pregnancy and obstetric outcomes of the didelphic and control groups were compared separately for singleton and twin pregnancies, and for all pregnancies combined.

RESULTS

In singleton pregnancies, women with uterus didelphys had increased risk of preterm birth (odds ratio (OR), 4.68; rate difference (RD), 0.14; P < 0.001), Cesarean section (OR, 2.80; RD, 0.17; P = 0.016) and birth weight < 2500 g (OR, 4.06; RD, 0.10; P = 0.017) compared to women with normal uterine morphology. In twin pregnancies, the presence of uterus didelphys was associated with increased risk of preterm delivery (OR, 4.79; RD, 0.37; P = 0.006), perinatal mortality (OR, 3.16; RD, 0.19; P = 0.043) and birth weight < 2500 g (OR, 9.57; RD, 0.35; P = 0.001).

CONCLUSIONS

The presence of uterus didelphys was associated with significantly increased risk of some adverse pregnancy outcomes compared to pregnancies with normal uterine morphology in women who underwent IVF/ICSI. A twin pregnancy in women with uterus didelphys was associated with worse perinatal outcome. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

P–405 The diagnosis and management of heterotopic intramural pregnancy after in vitro fertilization-embryo transfer: six-case series

Study question

What are the ultrasonic characteristics of heterotopic intramural pregnancy (HIMP)? How to manage and what about the clinical outcomes of HIMP?

Summary answer

Expectant management may be a considerable choice for an non-viable intramural pregnancy (IMP). Most intrauteine pregnancies (IUPs) of HIMPs seems to have good outcomes.

What is known already

Heterotopic pregnancy (HP) post in vitro fertilization is very rare in infertility women, with a prevalence of 0.04%. HIMP is one of the rarest types of HP, where one gestational sac (GS) is embedded within the endometrial cavity and the other one GS is implanted in the myometriun. HIMP was firstly and only described by Jiangtao Lyu et al. in 2018. So far, little is known about its natural history and ultrasonic imaging characteristics. And there is no consensus regarding the ultrasound diagnosis and clinical management for HIMP due to few evidence-based medicine records.

Study design, size, duration

A retrospective observational study was conducted of 6 infertile women who obtained a HIMP through in vitro fertilization-embryo transfer (IVF-ET) between January 2009 and December 2019 at our reproductive centre.

Participants/materials, setting, methods

Six infertile women conceived a HIMP via IVF-ET were retrospectively retrieved between January 2009 and December 2019 at the Reproductive and Genetic Hospital of CITIC-Xiangya (Changsha City, China). The ultrasound diagnosis, clinical management and pregnancy outcome of these cases were analysed. The ultrasound findings, therapeutic methods and clinical outcomes were obtained from the hospital’s electronic medical records. This study was approved by the local ethics committee. Main results and the role of chance: Six women with HIMPs were retrospectively analysed. Among them, 5 cases were revealed by ultrasound scans; however, one case was misdiagnosed. The diagnostic accuracy was 83.3%.

Five cases of HIMP were diagnosed at initial scan. The diagnostic time ranged from 22 to 38 days after ET (5 + 6 - 7 + 6 weeks). Among them, an intramural GS was observed in all 5 cases; embryonic cardiac activity (ECA) was detected in one case by the followed-up scans; there was a yolk sac only in one case; an empty GS was noted in 3 cases. An IUP was revealed in all 6 cases, and ECA was observed in 5 cases at the initial diagnosis or later. A GS with a yolk sac only was showed in one case.

Among the 5 diagnostic women, one case with a live IMP was treated with laparoscopy at 8 + 1 weeks, 4 cases were managed expectantly. Of them, the IUPs of 4 cases delivered live infants and one case managed expectantly experienced miscarriage. In one case, IMP was misdiagnosed as interstitial pregnancy at day–28 scan. Exploratory laparoscopy and foetal reduction were performed at 8 + 2 weeks. Laparoscopy confirmed an IMP and the retained IUP delivered a live infant.

Limitations, reasons for caution

The case numbers are too few to draw any objective conclusions, because of the extreme rarity of HIMP. Thus, a further multi-centre larger prospective study will help to confidently illustrate the clinical significance, and effective and appropriate management method for women with a HIMP.

Wider implications of the findings: Our study showed that HIMP may not be as rare as previously reported. Increased awareness of this condition, better comprehension of the diagnostic criteria and improved resolution of ultrasound equipment may result in more frequent and accurate detection of HIMP, which will be helpful for early management to preserve IUP.

Trial registration number

Not applicable.

P–568 Homozygous Pathogenic Variants in ACTL9 Cause Fertilization Failure and Male Infertility in Human and Mouse

Study question

What are the other male factors that cause total fertilization failure (TFF) excepting for variants in PLCZ1?

Summary answer

Homozygous variants in ACTL9 (actin like 9) cause abnormal localization of PLCζ in a loosened perinuclear theca (PT) structure and leads to TFF.

What is known already

In previous studies, investigators have reported that the female factors in TFF after intracytoplasmic sperm injection (ICSI) include pathogenic variants in WEE2, TLE6, and TUBB8, whereas for male factors, pathogenic variants in PLCZ1 were reported to be the primary cause of TFF, which account for approximately 30% of couples with male factors in TFF excluding globozoospermia. Most recently, it was reported that pathogenic variants in ACTL7A led to reduced expression and abnormal localization of PLCζ, thereby identifying this genetic variant as a potential cause of TFF.

Study design, size, duration

Fifty-four infertile couples with TFF or poor fertilization (fertilization rate of &lt; 20%) at the Reproductive and Genetic Hospital of CITIC-Xiangya during January 2014 to June 2020 were recruited into this study.

Participants/materials, setting, methods

Male factors were identified in (MOAT). WES analysis was used to analyze the genetic factors of individuals with male factors. Sperm morphological study was conducted by H&E staining and TEM. Immunostaining of PLCζ was used to analyze the status of sperm-borne activation factor. A knock-in mouse model was generated by CRISPER-Cas9 technology. Sperm from homozygous Actl9 variant mice were analyzed by TEM and ICSI. ICSI with AOA was performed in couples with ACTL9 variants.

Main results and the role of chance

A total of 54 couples with TFF or poor fertilization were screened, with 21 couples determined to have a male infertility factor by MOAT. Whole-exome sequencing of these 21 male individuals identified three homozygous pathogenic variants in ACTL9 in three individuals. ACTL9 variations led to abnormal ultrastructure of the PT, with PLCζ absent in the head and present in the neck of the mutant sperm, which contributed to failed normal calcium oscillations in oocytes and subsequent TFF. The key roles of ACTL9 in the PT structure and TFF after ICSI were further confirmed in Actl9-mutated mouse model. Furthermore, assisted oocyte activation by calcium ionophore exposure successfully overcame TFF and achieved live births in a couple with an ACTL9 variant.

Limitations, reasons for caution

The mechanism of how ACTL9 regulate PLCζ remains unknown.

Wider implications of the findings: It provided a genetic marker and a therapeutic option for individuals who have undergone ICSI without successful fertilization.

Trial registration number

not applioable

Serum glypican4 and glycosylphosphatidylinositol-specific phospholipase D levels are associated with adipose tissue insulin resistance in obese subjects with different glucose metabolism status

OBJECTIVES

Glypican4 (GPC4) is a novel adipokine associated with obesity and insulin resistance. GPC4 was cleaved by the glycosylphosphatidylinositol-specific phospholipase D (GPLD1) in an anchored site of the glycosylphosphatidylinositol, and then was released into the extracellular environment. Herein, we investigated the changes of serum GPC4 and GPLD1 levels in obese subjects with different glucose metabolism status and their relationship with adipose tissue insulin resistance index (Adipo-IR) in Chinese north populations.

METHODS

A total of 221 obese subjects and 37 normal controls (NC) were recruited in this study. Obese subjects were divided into normal insulin (NI) group, hyperinsulinemia (HI) group, impaired glucose tolerance (IGT) group, and type 2 diabetes mellitus (DM) group. Serum GPC4, GPLD1, and adiponectin were determined by commercially available ELISA kits.

RESULTS

Serum GPC4 levels in the HI, IGT, and DM groups were significantly higher than those in the NC and NI groups (2.27 ± 0.58 ng/mL, 2.21 ± 0.60 ng/mL, 2.49 ± 0.67 ng/mL vs. 1.70 ± 0.33 ng/mL, 1.93 ± 0.34 ng/mL, P < 0.05). GPC4 was positively correlated with GPLD1, which was the most important influencing factor of GPC4. Adipo-IR was independently and positively associated with serum GPC4 and GPLD1. For GPC4, after adjustment for confounders, the risk of adipose tissue insulin resistance in subjects with the highest tertile was 2.974-fold that of those with the lowest tertile (OR = 2.974, P = 0.013). For GPLD1, before adjustment for lipids, the increased probability still existed (Model 2, OR = 3.568, P = 0.003).

CONCLUSION

GPC4 is an adipokine associated with adipose tissue insulin resistance, and its activity may be regulated by GPLD1. GPC4 may be a marker for adipose tissue insulin resistance in Chinese north obese populations.

Effect of insulin-like growth factor-1 on promoting healing of skin ulcers in diabetic rats

To investigate the effect of exogenous insulin-like growth factor-1 (IGF-1) on the healing of skin ulcers in diabetic rats, male Sprague Dawleys (SD) rats with back skin ulcers were selected and divided into control group, model group and IGF-1 treatment group which received different doses of IGF-1 (0.5, 1.0, 1.5, and 2.0mg/L). The results showed that the healing speed of the skin ulcers was significantly affected by IGF-1, which reduced the size of wound (P less than 0.05). The expression of MMP-9 was enhanced while the expression of TIMP-1 was decreased in diabetic rats with skin ulcers. The IGF-1 treatment helped to re¬store the normal expression of both MMP-9 and TIMP-1 in diabetic rats with skin ulcers, and diabetic skin ulcers in the 1.5 mg/L IGF-1 group showed the best healing. Histological examination showed that after 20 days, fibroblasts in the IGF-1 experimental group with an appropriate concentration increased and the numbers of fibroblasts and capillaries were significantly higher than those of the other groups. Moreover, there were obvious wound surface contractions and re-epithelialization, and the new epithelium moved to the center of the wound faster. Therefore, it is concluded that an appropriate concentration of IGF-1 can significantly promote the healing of skin ulcers in diabetic rats.

[Effects of sural nerve nutrition vess els-supported flap for reconstruction of distal lower leg and ankle soft tissue defects]

Objective: To observe the effects of sural nerve nutrition vessels-supported flap for reconstruction of distal lower leg and ankle soft tissue defects. Methods: From June 2014 to June 2017, 37 patients with calf distal and ankle soft tissue defect were repaired with sural nerve nutrition vessels-supported flap, of them 12 cases with calf distal soft tissue defect wounds and 25 cases with ankle soft tissue defect wounds.The scope of flaps was 9 cm×4 cm to 18 cm×9 cm, anti-infection, anti-freezing and dressing treatments were carried out after operation.The results of two-point discrimination among reexamination were recorded. Results: All the flaps survived without ulcer and effusion, only 1 flap for reconstruction of medial malleolus swelled and deactivated at the beginning while it recovered with proper dressings.During the follow-up periods, all the flaps kept favorable feelings, aspects and functions, and the two-point discrimination was 5 to 15 mm [averaged (11.2±1.7) mm]. Conclusion: Sural nerve nutrition vessels-supported flap brings significant effects with excellent safety and reliability in repairing calf and ankle soft tissue defects.

[Acute toxicity and bio-distribution of silver nitrate and nano-silver with different particle diameters in rats]

Objective: To explore the acute toxic effect and the cumulative target organ of silver nitrate and nano-silver with two different particle diameters in rats. Methods: Thirty-six adult SD rats were divided into small particle size nano-silver group (SNS), large particle size nano-silver group (LNS), silver nitrate group (SN), and control group (C) according to the random number table, with 9 rats in each group. The rats of the four groups were respectively injected with 10 mg/mL nano-silver solution (particle diameter of 20 nm, prepared by saline) in silver dose of 30 mg/kg by tail vein for once, 10 mg/mL nano-silver solution (particle diameter of 100 nm, prepared by saline) in silver dose of 30 mg/kg, 1.67 mg/mL silver nitrate solution (prepared by glucose solution) in silver dose of 3 mg/kg, and 30 mg/mL polyvinylpyrrolidone solution (prepared by saline) in dose of 90 mg/kg. (1) Toxicity test. The general observation was performed within 14 days after injection, and the deviation between value of body mass before injection and each of that on post injection day (PID) 1, 7, and 14 were respectively recorded. On PID 1, 7, and 14, 3 rats of each group were harvested for determination of serum content of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein, and albumin by fully automatic biochemical analyzer. Then the rats were sacrificed immediately, and heart tissue, liver tissue, spleen tissue, lung tissue, kidney tissue, and brain tissue were collected to calculate the organ coefficient. Organ samples with obvious changes in organ coefficient were collected for histopathological observation by HE staining, with 3 samples in each group at each time point. (2) Bio-distribution. The specimens of heart, liver, spleen, lung, and kidney of rats from groups SNS, LNS, and SN were collected for detection of silver content by inductively coupled plasma mass spectrometry, with 3 samples in each group at each time point. Data were processed with analysis of variance of factorial design, LSD test, and Dunnett's T3 test. Results: (1) The general condition of rats in groups C and SN after injection were normal. The state of rats of groups SNS and LNS was poor with black secretion in the eye and other phenomena on PID 1, which recovered from PID 3 on. (2) The deviations between values of body mass before injection and that on PID 14 in rats of groups LNS and SN were significantly decreased as compared with deviation of group C (with P values below 0.01), but deviation of group SNS was not significantly changed (P>0.05). The deviations between values of body mass before injection and each of that on PID 1 and 7 in rats in the other three groups were similar to those in group C (with P values above 0.05). (3) Compared with those in group C, the serum content of total protein of rats in group SN on PID 1 was significantly decreased, and liver coefficient was significantly increased (with P values below 0.05). On PID 1, the serum content of ALT of rats in group LNS was (61.0±8.7) U/L, which was significantly higher than that in group C [(40.0±4.6) U/L, P<0.01]. Compared with those in group C [(126.0±3.5) U/L and 4.05±0.23], the serum content of AST of rats in groups SNS and LNS on PID 1[(249.7±107.2) and (237.0±38.3) U/L] was significantly increased, and liver coefficients (3.50±0.38 and 3.31±0.07) were significantly decreased, with P values below 0.05. Compared with those in group C [(69.2±4.8) U/L and 4.32±0.39], the serum content of AST of rats in groups SNS and LNS on PID 7 [(181.0±51.5) and (167.7±16.5) U/L] was also significantly increased, and liver coefficients (3.55±0.18 and 3.62±0.21) were also significantly decreased, P<0.05 or P<0.01. On PID 14, the four liver biochemical indexes in serum and all organ coefficients of rats in the other three groups were similar to those in group C (with P values above 0.05). (4) The liver of rats in group SN had slight degeneration on PID 1, the liver cells around the central vein of liver of rats in group SNS had slight degeneration on PID 7, and the liver cells got severely eosinophilic degeneration in liver of rats in group LNS on PID 7. There was no significant pathological change in the liver of rats in each group at the rest time points. (5) The silver content of lung and kidney in rats of group SNS on PID 1, that of spleen and kidney in rats of group LNS on PID 1, and that of heart and kidney in rats of groups LNS and SNS on PID 7 was significantly less than that of group SN (with P values below 0.05). The silver content of liver and spleen in rats of group SNS on PID 14 was significantly more than that of group SN (with P values below 0.05). Compared with that of group SN, the silver content of lung on PID 1 and liver on PID 7 in rats of group LNS was significantly increased (with P values below 0.05). On PID 14, there was no significant change in the silver content of all organs of rats between group SN and group LNS (with P values above 0.05). The silver content of heart, lung, and kidney on PID 1 and heart on PID 7 in rats of group LNS was significantly more than that of group SNS (with P values below 0.05). On PID 14, the silver content of each organ of rats in group SNS was close to that in group LNS (with P values above 0.05). Conclusions: Silver nitrate and nano-silver with two different particle diameters have a short acute toxic effect on the liver of rats, and the liver has certain ability of self-healing. Nano-silver is mainly accumulated in the liver. The distribution of nano-silver with large particle diameter in organs is more widely than that of nano-silver with small particle diameter.

Whole-exome sequencing identifies a homozygous donor splice-site mutation in STAG3 that causes primary ovarian insufficiency

Primary ovarian insufficiency (POI) is the depletion or loss of normal ovarian function, which cause infertility in women before the age of 40 years. Two homozygous germline truncation mutations in STAG3 gene had been reported to causes POI in consanguineous families. Here, we aimed to identify the genetic cause of POI in 2 affected sisters manifested with primary amenorrhea and partial development of secondary sexual characters with normal range of height of a consanguineous Han Chinese family. Whole-exome and Sanger sequencing identified a homozygous donor splice-site mutation (NM_012447.2: c.1573+5G>A) in the STAG3 gene. RT-PCR revealed that the mutation causes loss of wild-type donor splice-site which leads to aberrant splicing of STAG3 mRNA and consecutive formation of STAG3 alternative transcript (p.Leu490Thrfs*10) . This is the first report of splice-site mutation of STAG3 gene causes POI in 2 Han Chinese patients.

Mps1 kinase regulates tumor cell viability via its novel role in mitochondria

Targeting mitotic kinase monopolar spindle 1 (Mps1) for tumor therapy has been investigated for many years. Although it was suggested that Mps1 regulates cell viability through its role in spindle assembly checkpoint (SAC), the underlying mechanism remains less defined. In an endeavor to reveal the role of high levels of mitotic kinase Mps1 in the development of colon cancer, we unexpectedly found the amount of Mps1 required for cell survival far exceeds that of maintaining SAC in aneuploid cell lines. This suggests that other functions of Mps1 besides SAC are also employed to maintain cell viability. Mps1 regulates cell viability independent of its role in cytokinesis as the genetic depletion of Mps1 spanning from metaphase to cytokinesis affects neither cytokinesis nor cell viability. Furthermore, we developed a single-cycle inhibition strategy that allows disruption of Mps1 function only in mitosis. Using this strategy, we found the functions of Mps1 in mitosis are vital for cell viability as short-term treatment of mitotic colon cancer cell lines with Mps1 inhibitors is sufficient to cause cell death. Interestingly, Mps1 inhibitors synergize with microtubule depolymerizing drug in promoting polyploidization but not in tumor cell growth inhibition. Finally, we found that Mps1 can be recruited to mitochondria by binding to voltage-dependent anion channel 1 (VDAC1) via its C-terminal fragment. This interaction is essential for cell viability as Mps1 mutant defective for interaction fails to main cell viability, causing the release of cytochrome c. Meanwhile, deprivation of VDAC1 can make tumor cells refractory to loss of Mps1-induced cell death. Collectively, we conclude that inhibition of the novel mitochondrial function Mps1 is sufficient to kill tumor cells.

[Effect of astaxanthin on vascular smooth muscle cells proliferation induced by platelet derived growth factor-BB]

OBJECTIVE

To investigate the effect of astaxanthin (AST) on vascular smooth muscle cells (VSMCs) proliferation in vitro induced by platelet derived growth factor-BB (PDGF-BB), and to explore its possible mechanism.

METHODS

There were 4 groups in this experiment: blank control group, PDGF-BB group, PDGF-BB+ AST group, AST group. After the cells received different intervention for the indicated time, the cell growth was determined by Trypan blue staining; cell proliferation was demonstrated using CCK-8 kit; the cell cycle progression was analyzed by flow cytometry, and the mRNA expression of cyclin D1, cyclin E, CDK6, CDK4, cyclin kinase inhibitor protein P21 was determined by real-time PCR; reactive oxygen species (ROS) generation was detected using a Microplate reader; the total and phosphorylated forms of ERK1/2, p38 MAPK, JNK was observed in AST pretreated VSMCs in 5, 10 and 15 min after PDGF-BB treatment by Western blot analysis.

RESULTS

(1) Cell viability: AST and/or PDGF-BB did not induce VSMCs necrosis with the different concentration compared with untreated cells (P>0.05). (2) Cell proliferation: PDGF-BB induced VSMCs proliferation (2.5±0.3 vs 1, P<0.01), while AST reversed the effect in a concentration-dependent manner when co-treated with PDGF-BB (all P<0.01); Cell cycle: Flow cytometry analysis showed that AST at a dose of 25 μmol/L reduced the percentages of cells in S phase and increased the G0/G1 populations in PDGF-BB-stimulated VSMCs; mRNA expression of the check-point proteins: Real Time PCR results demonstrated that, compared with the control group, the mRNA expression of CDK6, CDK4, cyclin D1, cyclin E in the PDGF-BB group was higher (4.20±0.30, 2.90±0.18, 3.50±0.30, 2.70±0.11 vs 1, all P<0.01), while p21 mRNA expression was lower (0.52±0.03 vs 1, P<0.01), while AST reversed these effects when co-treated with PDGF-BB. (3) ROS expression: compared with the control group, ROS level was significantly higher in the PDGF-BB group (2.10±0.09 vs 1, P<0.01), while AST reversed the effect in a concentration-dependent manner when co-treated with PDGF-BB (all P<0.01). (4) Signaling pathway: AST blocking the proliferation of VSMCs induced by PDGF-BB was related to suppress ERK1/2, p-p38 MAPK signaling pathway, but little effect to JNK. Conclutions: These results demonstrate that AST can block the proliferation and migration of VSMCs through G0/G1 to S phase of the cell cycle arrest. Further study indicates that AST suppress PDGF-BB-induced VSMCs proliferation is associated with an inhibition of ROS generation and ERK1/2, p-p38 MAPK signal pathways.

Mutations of glucocerebrosidase gene and susceptibility to Parkinson's disease: An updated meta-analysis in a European population

This meta-analysis aims to investigate the association between mutations of glucocerebrosidase (GBA) gene and susceptibility to Parkinson's disease (PD) in a European population. Several electronic databases were extensively searched. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the association. In total, fourteen published papers screening L444P, N370S and other GBA variants were identified. The GBA mutations were significantly associated with PD in the European population. Subgroup analysis stratified by the age of onset (AAO) revealed that the association between GBA mutations and PD existed in the patients with age at onset ⩽50 years but did not exist in the patients with age at onset >50 years. Furthermore, the associations between N370S, and L444P with PD were also analyzed to explore the roles of the two most frequent GBA mutations in the development of PD. The results showed that significant associations between N370S, and L444P with PD were observed, respectively. Overall, the study supported that GBA mutations were a risk factor for PD in the European population. Patients with early-onset were more likely to carry GBA mutations than those with late-onset. Moreover, both L444P and N370S were associated with increased PD risk.

Expression of VEGF and its effect on cell proliferation in patients with chronic myeloid leukemia

OBJECTIVE

The aim of this study is to investigate the expression of vascular endothelial growth factor (VEGF) in the serum of patients with chronic myeloid leukemia (CML) and the effect of VEGF on cell proliferation.

PATIENTS AND METHODS

Serum VEGF levels in 12 CML patients (7 chronic phase, 5 blast crisis phase) were measured using enzyme linked immunosorbent assay (ELISA). VEGF expression was interfered by transfection of K562 cells. VEGF mRNA levels in transfected K562 cells were determined using RT-PCR and the effect of VEGF on the proliferation of transfected K562 cells was investigated.

RESULTS

VEGF expression levels were significantly higher in CML patients than normal controls and significantly increased during blast crisis phase than during chronic phase. Compared to controls, the proliferation of the K562 cells was suppressed when VEGF expression was inhibited. However, the inhibited proliferation of K562 cells after gene silencing of VEGF was partially abolished after introducing exogenous VEGF into the cells.

CONCLUSIONS

VEGF plays an important role in the initiation and development of CML and monitoring serum VEGF assists guiding the treatment and predicting the prognosis of CML.

Autophagy promotes paclitaxel resistance of cervical cancer cells: involvement of Warburg effect activated hypoxia-induced factor 1-α-mediated signaling

Paclitaxel is one of the most effective chemotherapy drugs for advanced cervical cancer. However, acquired resistance of paclitaxel represents a major barrier to successful anticancer treatment. In this study, paclitaxel-resistant HeLa sublines (HeLa-R cell lines) were established by continuous exposure and increased autophagy level was observed in HeLa-R cells. 3-Methyladenine or ATG7 siRNA, autophagy inhibitors, could restore sensitivity of HeLa-R cells to paclitaxel compared with parental HeLa cells. To determine the underlying molecular mechanism, differentially expressed proteins between HeLa and HeLa-R cells were identified by two-dimensional gel electrophoresis coupled with electrospray ionization quadrupole time-of-flight MS/MS. We found glycolysis-associated proteins were upregulated in HeLa-R cell lines. Inhibition of glycolysis by 2-deoxy-D-glucose or koningic acid could decrease autophagy and enhance sensitivity of HeLa-R cells to paclitaxel. Moreover, glycolysis could activate HIF1-α. Downregulation of HIF1-α by specific siRNA could decrease autophagy and resensitize HeLa-R cells to paclitaxel. Taken together, a possible Warburg effect activated HIF1-α-mediated signaling-induced autophagic pathway is proposed, which may provide new insight into paclitaxel chemoresistance.

HMGB1 is involved in chronic rejection of cardiac allograft via promoting inflammatory-like mDCs

Chronic rejection that leads to diffuse narrowing and occlusion of graft vessels is the most important cause of morbidity and mortality following cardiac transplantation. The role and underlying mechanism of high-mobility group box 1 (HMGB1), as an established inflammatory mediator in acute rejection, remains poorly understood in chronic rejection. Here, we assessed the effects and mechanisms of HMGB1 on the chronic rejection using single MHC Class II-mismatched mouse cardiac transplantation model. It was found that HMGB1 was increased accompanying with the development of chronic rejection, while blockade of HMGB1 with specific neutralizing mAb substantially ameliorated chronic rejection-mediated vasculopathy and fibrosis of allograft, as well as markedly decreased T cell infiltration and production of IL-17A and interferon-gamma in allograft and recipient's spleen. Further, anti-HMGB1 antibody treatment significantly declined the number and frequency of mature dendritic cells (DCs) in allograft and recipient's spleen, especially CD11b(+) Ly6C(high) matured DCs that share the phenotypes with inflammatory-DCs. These findings indicate that HMGB1 contributes to chronic rejection, and HMGB1 blockade may be a novel mean to disrupt the proinflammatory loop after heart transplantation.

Using SNP array to identify aneuploidy and segmental imbalance in translocation carriers

Translocation is one of the more common structural rearrangements of chromosomes, with a prevalence of 0.2%. The two most common types of chromosomal translocations, Robertsonian and reciprocal, usually result in no obvious phenotypic abnormalities when balanced. However, these are still associated with reproductive risks, such as infertility, spontaneous abortion and the delivery of babies with mental retardation or developmental delay.

In recent years, array-based whole-genome amplification (WGA) technologies, including microarray comparative genomic hybridization (array CGH; aCGH) and single-nucleotide polymorphism (SNP) micro-arrays, have enabled the screening of every chromosome for whole-chromosome aneuploidy and segmental imbalance. These techniques have been shown to have clinical application for translocation carriers. Promising studies have indicated that array-based PGD of translocation carriers can lead to transfer pregnancy rates of 45–70% [2].

In addition to genetic testing techniques, the embryo biopsy stage (polar body, cleavage embryo or blastocyst) and the mode of embryo transfer (fresh or frozen embryos) can affect the outcome of PGD. It is now generally recommended that blastomere biopsy should be replaced by blastocyst biopsy to avoid a high mosaic rate and biopsy-related damage to cleavage-stage embryos, which might affect embryo development. However, more clinical data are required to confirm that the technique of SNP array-based PGD (SNP-PGD) combined with trophectoderm (TE) biopsy and frozen embryo transfer (FET) is superior to traditional FISH-PGD combined with Day 3 (D3) blastomere biopsy and fresh embryo transfer.

CpG7909 adjuvant enhanced immunogenicity efficacy in mice immunized with ESAT6-Ag85A fusion protein, but does not confer significant protection against Mycobacterium tuberculosis infection

AIMS

This study aimed to investigate the ability of CpG7909 adjuvant to enhance immunogenicity and protective efficacy of a subunit vaccine composed of ESAT6-Ag85A fusion protein (Pe685a) of Mycobacterium tuberculosis.

METHODS AND RESULTS

ELISA was used to detect specific antibody and IFN-γ expression in sera; ELISPOT, to detect IFN-γ expression in splenocytes; MTT assay and FACS, to detect T-lymphocytes proliferation in spleens; and RT-PCR, to detect cytokines expression in lungs of mice after immunization. Bacterial load and histopathological lesions in lungs or spleens of mice challenged with Myco. tuberculosis H37Rv strain were analysed. Compared with incomplete Freund's adjuvant, CpG7909 induced more potent production of Pe685a-specific IgG2a/IgG1 antibody and higher expression of IFN-γ in sera, stimulated more generation of antigen-specific IFN-γ-secreting splenocytes, enhanced frequencies of CD3(+) CD4(+) and CD3(+) CD8(+) T-lymphocytes in spleen and increased transcription of TNF-α, IFN-γ, IL-6 and TLR9 in lung. However, lower bacterial load in lung and less severe lung pathology were not observed in CpG7909 group mice.

CONCLUSIONS

CpG7909 is able to enhance immunological effects of Pe685a subunit vaccine, but does not confer significant protective efficacy against Myco. tuberculosis infection.

SIGNIFICANCE AND IMPACT OF THE STUDY

CpG7909 as an adjuvant of subunit vaccine against Myco. tuberculosis is worthy of further investigation.

Local hemodynamic disturbance accelerates early thrombosis of small-caliber expanded polytetrafluoroethylene grafts

OBJECTIVE

Small-caliber expanded polytetrafluoroethylene (ePTFE) grafts cannot be used widely in the clinical situation because of early thrombosis and occlusion. This unsolved and under-recognized problem warrants further investigation.

METHODS

Grafts of uncoated ePTFE (n = 6) and anti-CD34-coated ePTFE (n = 6) were implanted unilaterally into the carotid artery in 12 domestic pigs. Ultrasonography was used to test the proximal and distal anastomotic stoma morphology, diameters and blood velocities. A thrombosis instrument was used to examine the blood coagulation state. After seven days, the pigs were sacrificed and the implanted grafts were excised for general and histological analysis. Computational fluid dynamics was used to investigate the blood flow fields of the implanted grafts and to calculate parameters that might be indicative of thrombosis.

RESULTS

Thrombosis was detected in 10 of 12 (83.3%) implanted ePTFE grafts, 5 in uncoated grafts and 5 in anti-CD34-coated grafts. Endothelial cell coverage was observed in both uncoated and anti-CD34-coated grafts. No obvious abnormalities in anastomotic stoma or blood coagulation state were observed. Computer-based local hemodynamic simulation showed the low flexibility of synthetic ePTFE grafts caused obvious coarctation. Local wall pressure, velocity and wall shear stress were much higher than in the contralateral normal vessel.

CONCLUSIONS

The patency of small-caliber ePTFE grafts for clinical use is impaired by early thrombosis due to mixed causes. Local hemodynamic disturbance was the most powerful predictor of early thrombosis. Decreasing local hemodynamic disturbance, improving the quality of anastomotic stoma, selecting reasonable anticoagulation strategies and promoting rapid endothelialization may increase the long-term patency of small-caliber vascular grafts.

Segregation of secondary metabolite biosynthesis in hybrids of Fusarium fujikuroi and Fusarium proliferatum

Fusarium fujikuroi and Fusarium proliferatum are two phylogenetically closely related species of the Gibberella fujikuroi species complex (GFC). In some cases, strains of these species can cross and produce a few ascospores. In this study, we analyzed 26 single ascospore isolates of an interspecific cross between F. fujikuroi C1995 and F. proliferatum D4854 for their ability to produce four secondary metabolites: gibberellins (GAs), the mycotoxins fusarin C and fumonisin B(1), and a family of red polyketides, the fusarubins. Both parental strains contain the biosynthetic genes for all four metabolites, but differ in their ability to produce these metabolites under certain conditions. F. fujikuroi C1995 produces GAs and fusarins, while F. proliferatum D4854 produces fumonisins and fusarubins. The segregation amongst the progeny of these traits is not the expected 1:1 Mendelian ratio. Only eight, six, three and three progeny, respectively, produce GAs, fusarins, fumonisin B(1) and fusarubins in amounts similar to those synthesized by the producing parental strain. Beside the eight highly GA(3)-producing progeny, some of the progeny produce small amounts of GAs, predominantly GA(1), although these strains contain the GA gene cluster of the non-GA-producing F. proliferatum parental strain. Some progeny had recombinant secondary metabolite profiles under the conditions examined indicating that interspecific crosses can yield secondary metabolite production profiles that are atypical of the parent species.

Bioethanol production from hydrolysates of inulin and the tuber meal of Jerusalem artichoke by Saccharomyces sp. W0

It has been confirmed that Saccharomyces sp. W0 can produce high concentration of ethanol. However, this yeast strain cannot secrete inulinase. Therefore, in this study, inulin was hydrolyzed into reducing sugar by the recombinant inulinase produced by Pichia pastoris X-33/pPICZaA-INU1. It was found that 38.2U of the recombinant inulinase per gram of inulin was suitable for the inulin hydrolysis and ethanol production by Saccharomyces sp. W0 and the fermentation period was 120 h. At the end of the fermentation, over 14.6 ml of ethanol per 100ml of the fermented medium was produced, the ethanol productivity was over 0.384 g of ethanol/g of inulin and over 98.8% of total sugar was utilized. When the Saccharomyces sp. W0 was grown in the mixture of 4.0% hydrolysate of soybean meal and 20.0% of the hydrolysate of inulin for 120 h, over 14.9 ml of ethanol per 100ml of the fermented medium was yielded, the ethanol productivity was over 0.393 g of ethanol/g of inulin and 98.9% of total sugar was used by the yeast strain. When Saccharomyces sp. W0 carrying the same inulinase gene was grown in the medium containing 50 g of the tuber meal of Jerusalem artichoke per 100ml for 144 h, over 12.1+/-0.35%ml of ethanol per 100ml of the fermented medium was yielded, the ethanol productivity was 0.319+/-0.9 g of ethanol/g of sugar and 3.7% (w/v) of total sugar and 0.5% (w/v) of reducing sugar were left in the fermented media.

Mesenchymal stroma cells improve hyperglycemia and insulin deficiency in the diabetic porcine pancreatic microenvironment

BACKGROUND

Stem cell differentiation is controlled by extracellular cues from the environment and by intrinsic genetic programs within the stem cell. The present study aimed to explore whether mesenchymal stromal cells (MSC) could improve hyperglycemia and insulin production in the diabetic microenvironment.

METHODS

We transplanted male porcine bone marrow-derived EGFP-expressing MSC directly into female diabetic porcine pancreas by multi-point injection. Enzyme-linked immunosorbent assay (ELISA) and fluorescent immunohistochemistry were used to analyze recipients' sera and pancreas tissues for assessment of the therapeutic effect.

RESULTS

Blood glucose levels decreased gradually in MSC-treated recipients from 15 days after the transplantation compared with untreated diabetic controls (15.94+/-0.31 mmol/L versus 16.66+/-0.11 mmol/L; P=0.01). Blood insulin increased and glucagons decreased notably in recipients from 2 weeks post-transplantation compared with untreated diabetic controls (0.049+/-0.004 microg/L versus 0.037+/-0.02 microg/L and 392.9+/-20.3 ng/L versus 433.1+/-27.6 ng/L). Hematoxylin and eosin (HE)-stained sections demonstrated that the number of islets from each section was markedly increased in recipients compared with that of diabetic controls (10.9+/-2.2 versus 4.6+/-1.4; P<0.05) and similar to that of normal controls (10.9+/-2.2 versus 12.6+/-2.6; P>0.05). The newly formed islets were smaller than normal islets (47.2+/-19.6 microm versus 119.6+/-27.7 microm; P<0.05). Analysis of pancreatic sections for EGFP in recipients indicated that the transplanted MSC survived within the pancreas. Insulin immunoreactivity of pancreatic islets showed that the newly formed islets expressed insulin.

DISCUSSION

MSC could improve diabetes upon pancreatic microenvironment without obvious immune rejections. This has theoretical and clinical applications.

Nonlinear pressure shifts of alkali-metal atoms in inert gases

Precise measurements show that the microwave resonance frequencies of ground-state Rb or Cs atoms have a nonlinear dependence on the pressure of the buffer gases Ar and Kr. No nonlinearities were observed in the gases He or N(2). These observations strongly suggest that the nonlinearities are due to the van der Waals molecules that form in Ar and Kr, but not in He or N(2). The nonlinear part of the shifts is largest in the pressure range of a few tens of torr, similar to the operating pressures of gas-cell atomic clocks. The observed shifts are very well described by a simple function, parametrized by the effective three-body formation rate of molecules and by the effective product of the collisionally limited lifetime times the shift of the hyperfine coupling coefficient in the molecule.

Mesenchymal stem cells contribute to insulin-producing cells upon microenvironmental manipulation in vitro

BACKGROUND

Extracellular microenvironment and intrinsic genetic programs determine the fate of stem cells. We observed whether mesenchymal stem cells (MSCs) contributed to insulin-producing cells in a manipulated microenvironment.

METHODS

We delivered pancreatic pieces into Niobium-Coated Dynamatrix to construct a simulated pancreatic microenvironment, upon which soluble cytokine exchange and direct cell-cell contact between MSCs and pancreatic cells could occur. Bone marrow-derived MSCs were cultured upon the microenvironment. Differentiated isletlike cells were observed under an inverted microscope. Insulin in supernates was measurement by enzyme-linked immunosorbent assay. Insulin and c-peptide expression were verified by fluorescent immunocytochemistry and fluorescence in situ hybridization. Apoptosis of isletlike masses in high-glucose DMEM was detected by FACS.

RESULTS

After 3 to 4 weeks in culture, typical isletlike masses were observed. Insulin secreted by differentiated cells (414.47+/-30.30 mIU/L) was much greater than that of undifferentiated cells (4.89+/-1.01 mIU/L; P<.05). Insulin and c-peptide expression were positive both in protein and mRNA levels. The transdifferentiated isletlike mass did not undergo apoptosis after another 3 weeks of culture in high-glucose DMEM.

CONCLUSION

This simulated injury microenvironment without induction guided MSCs to functional isletlike cells hopefully to replace beta cells.