First pregnancy in China after ovarian tissue transplantation to prevent premature ovarian insufficiency

OBJECTIVE

This article reports the first case of pregnancy after frozen-thawed ovarian tissue transplantation to prevent iatrogenic premature ovarian insufficiency in China.

METHODS

Ovarian tissue cryopreservation was performed in a patient with myelodysplastic syndrome (MDS) before multi-agent chemotherapy and hematopoietic stem cell transplantation. Two years later, she showed complete remission from MDS, and six frozen-thawed ovarian tissue strips were transplanted into the peritoneal pocket.

RESULTS

The patient's ovarian activity was restored 3 months after transplantation, and pregnancy occurred spontaneously 27 months after grafting. Until now, the pregnancy has progressed for 30 weeks, and the repeated ultrasound showed normal fetal development.

CONCLUSION

This is the first pregnancy resulting from ovarian tissue cryopreservation and transplantation in China.

Prenatal exposure to solar radiation and hypertensive disorders of pregnancy

OBJECTIVE

To examine the association between prenatal exposure to solar radiation and hypertensive disorders of pregnancy (HDP).

DESIGN

A multicentre retrospective study.

SETTING

19 hospitals in the USA.

POPULATION

205 888 women with singleton gestation from the Consortium on Safe Labor (2002-2008).

MAIN OUTCOME MEASURES

Gestational hypertension, pre-eclampsia/eclampsia, and pre-eclampsia superimposed on chronic hypertension.

METHODS

Medical records of the participants were linked to solar radiation obtained from the National Solar Radiation Database. Average daily solar radiation of each woman was estimated over the entire pregnancy period and over three trimesters during pregnancy according to hospital sites. Generalised estimated equation was applied to investigate the relationship between quartiles of average daily solar radiation and HDP. Restricted cubic spline was applied to assess the nonlinear associations.

RESULTS

Higher average solar radiation during the entire pregnancy was associated with reduced risks of HDP. Compared with the 1st quartile of solar radiation during the entire pregnancy, odds ratios (ORs) of the 2nd, 3rd and 4th quartiles were respectively 0.80 (95% CI 0.72-0.90), 0.63 (95% CI 0.55-0.73), 0.65 (95% CI 0.54-0.78) for gestational hypertension; 0.66 (95% CI 0.57-0.76), 0.61 (95% CI 0.51-0.73), 0.77 (95% CI 0.62-0.95) for pre-eclampsia, and 0.44 (95% CI 0.36-0.55), 0.42 (95% CI 0.35-0.49), 0.60 (95% CI 0.46-0.78) for superimposed pre-eclampsia.

CONCLUSION

Exposure to higher daily solar radiation during pregnancy is associated with a decreased risk of HDP. The protective effect was stronger for superimposed pre-eclampsia than for pre-eclampsia or gestational hypertension.

TWEETABLE ABSTRACT

Exposure to higher daily solar radiation during pregnancy is associated with a decreased risk of HDP.

Stretchable and Compressible Si3 N4 Nanofiber Sponge with Aligned Microstructure for Highly Efficient Particulate Matter Filtration under High-Velocity Airflow

Particulate matter (PM) is one of the most severe air pollutants and poses a threat to human health. Air filters with high filtration efficiency applied to the source of PM are an effective way to reduce pollution. However, many of the present filtration materials usually fail because of their high pressure drop under high-velocity airflow and poor thermal stability at high temperatures. Herein, a highly porous Si₃ N₄ nanofiber sponge (Si₃ N₄ NFS) assembled by aligned and well-interconnected Si₃ N₄ nanofibers is designed and fabricated via chemical vapor deposition (CVD). The resulting ultralight Si₃ N₄ NFS (2.69 mg cm^-3 ) processes temperature-invariant reversible strechability (10% strain) and compressibility (50% strain), which enables its mechanical robustness under high-velocity airflow. The highly porous and aligned microstructure result in a Si₃ N₄ NFS with high filtration efficiency for PM_2.5 (99.97%) and simultaneous low pressure drop (340 Pa, only <0.33% of atmospheric pressure) even under a high gas flow velocity (8.72 m s^-1 ) at a high temperature (1000 °C). Furthermore, the Si₃ N₄ NFS air filter exhibits good long-term service ability and recyclability. Such Si₃ N₄ NFS with aligned microstructures for highly efficient gas filters provides new perspectives for the design and preparation of high-performance filtration materials.

[Immune regulatory effect of tacrolimus in patients with severe aplastic anemia and in murine model]

Objective: To investigate the immunomodulatory effect of tacrolimus in severe aplastic anemia (SAA). Methods: Patients diagnosed with SAA at the Department of Hematology, General Hospital of Tianjin Medical University from June 2015 to January 2018 were enrolled. CD8⁺T cells were sorted by immunomagnetic separation from peripheral blood of SAA patients. MTT method was used to detect the proliferation of CD8⁺T cells. The SAA mouse model was established by total body irradiation (TBI) and donor lymphocyte infusion (DLI). There were 10 normal controls without pretreatment, 10 rats in TBI group, 15 rats received TBI and DLI. The expression of perforin and granzyme in CD8⁺T cells and the ratio of CD4⁺/CD8⁺cells in peripheral circulation were measured by flow cytometry. The level of interferon-γ (IFN-γ) in medium supernatant of cultured CD8⁺T cells was tested with enzyme-linked immunosorbent assay (ELISA). SAA mouse model was established to study the recovery of hemogram and survival time after treatment. Results: A total of 16 SAA patients were enrolled, and there were 10 males and 6 females, with a median age of 35 (22-49) years. Tacrolimus inhibited the proliferation of CD8⁺T cells when IL-2 concentration was 20.0,200.0 and 2 000.0 U/ml (P<0.05). The expression of perforin in CD8⁺T cells of SAA patients treated with tacrolimus was significantly lower than that in blank control group and IL-2 group [(2.25±0.76)%, (6.70±0.82)% vs (9.10±1.90)%,all P<0.05]. The level of IFN-γ in CD8⁺T cells group after applying tacrolimus was significantly lower than that in the blank control group (P<0.05). After 10 days of administration, the peripheral blood hemoglobin (Hb), white blood cell (WBC) and platelet (PLT) counts of SAA mice in tacrolimus group were all higher than those in SAA group (all P<0.05). The expression of perforin in CD8⁺T cells in tacrolimus group was significantly lower than that in SAA group [(18. 39±6.65) vs (29. 99±9.83),P<0.05]. The median survival time of SAA group was 18.6 days, and the 90 day survival rate was 0. The median survival time of tacrolimus group was 44.6 days, and the 90 day survival rate was 80%. The survival time of SAA mice in tacrolimus group was significantly longer than that in SAA group (P<0.05). Conclusion: The immunomodulatory effect of tacrolimus in SAA is similar to CsA. It has an immunosupressive effect on CD8⁺T lymphocyte.

Alternating Multilayered Si3N4/SiC Aerogels for Broadband and High-Temperature Electromagnetic Wave Absorption up to 1000 °C

Lightweight electromagnetic (EM) wave absorbers made of ceramics have sparked tremendous interest for applications in EM wave interference protection at high temperatures. However, EM wave absorption by pure ceramics still faces huge challenges due to the lack of efficient EM wave attenuation modes. Inspired by the energy dissipation mechanism during fracture of lobster shells with a soft and stiff multilayered structure, we fabricate a high-performance EM wave absorption ceramic aerogel composed of an alternating multilayered wave transparent Si₃N₄ (N) layer and wave absorption SiC (C) layer by a simple restack method. The obtained N/C aerogel shows ultralow density (∼8 mg/cm³), broad effective absorption bandwidth (8.4 GHz), strong reflection loss (-45 dB) at room temperature, and excellent EM wave absorption performance at high temperatures up to 1000 °C. The attenuation of EM wave mainly results from a "reflection-absorption-zigzag reflection" process caused by the alternating multilayered structure. The superior absorption performance, especially at high temperatures, makes the N/C aerogel promising for next-generation wave absorption devices served in high-temperature environments.

[Longitudinal surveillance of schistosomiasis in hilly regions of Sichuan Province from 2015 to 2019]

OBJECTIVE

To investigate the changes in the endemic situation of schistosomiasis in national surveillance sites of Sichuan Province, so as to provide the scientific evidence for formulating the schistosomiasis elimination strategy.

METHODS

From 2015 to 2019, 63 national schistosomiasis surveillance sites were assigned in Sichuan Province, in which Schistosoma japonicum infections were monitored in humans, livestock, wild feces and snails. The monitoring data were descriptively analyzed.

RESULTS

A total of 94 119 person-time local residents were serologically screened for S. japonicum infections in 63 national surveillance sites of Sichuan Province from 2015 to 2019, with sero-prevalence rates ranging from 1.28% to 3.11%, and the sero-positives were predominantly detected in local residents at ages of over 50 years and in farmers. A total of 94 119 person-time mobile populations were serologically screened for S. japonicum infections in the national surveillance sites during the 5-year period, with sero-prevalence of 1.10% to 1.59%. There were no egg-positives identified in either local residents or mobile populations. Among the 6 126 herd-time livestock detected, no egg-positives were identified, and no S. japonicum infection was detected in the 205 wild feces. Snail survey was performed covering an area of 8 484.08 hm², and 724.80 hm² snail habitats were identified, including 2.43 hm² emerging snail habitats and 63.00 hm² re-emerging snail habitats. The mean occurrence of frames with snails was 6.87% to 19.63%, and the mean density of living snails was 0.18 to 0.62 snails/0.1 m² in the national surveillance sites of Sichuan Province from 2015 to 2019; however, no S. japonicum infection was detected in snails.

CONCLUSIONS

The endemic situation of schistosomiasis has reduced to the lowest level in Sichuan Province; however, there is a rise in snail habitats, and there is still a risk of schistosomiasis resurgence. Further improvements of the surveillance system for schistosomiasis are required to achieve the goal of schistosomiasis elimination in Sichuan Province as soon as possible.

Circulating miR-374b-5p negatively regulates osteoblast differentiation in the progression of osteoporosis via targeting Wnt3 AND Runx2

Osteoporosis is defined as an aging-related skeletal disorder involving deterioration of bone mass and bone structure, and consequently, increased risk of fractures. Emerging evidence indicates the dysregulation of microRNAs (miRNAs) in the progression of osteoporosis. However, whether such associated miRNAs control osteoblast differentiation or constitute therapeutic targets remains elusive. In the present study, we found elevated circulating miR-374b-5p level associated with postmenopausal osteoporosis. miR-374b-5p served as a critical suppressor of osteoblast differentiation. We further identified that miR-374b-5p directly targeted Wnt family member 3 (Wnt3) and Runt-related transcription factor 2 (Runx2) through its 3'-untranslated regions (3'UTRs). Moreover, the antagonist of miR-374b-5p could promote bone formation in ovariectomy (OVX)-induced mice. Together, our results revealed that miR-374b-5p directly targeted Wnt3 and Runx2, negatively regulating osteoblast differentiation and bone formation. Collectively, circulating miR-374b-5p in the serum might serve as a potential diagnostic and therapeutic strategy for osteoporosis.

[Analysis of factors affecting health-related behaviors for schistosomiasis prevention and control among primary and secondary school students in Sichuan Province]

OBJECTIVE

To analyze the influencing factors of health-related behaviors for schistosomiasis prevention and control among primary and secondary school students in Sichuan Province using a multilevel and multivariate logistic model, so as to provide the theoretical evidence for developing the schistosomiasis prevention and control strategy among primary and secondary school students in Sichuan Province.

METHODS

A multi-stage sampling was conducted among 63 schistosomiasis-endemic counties (districts) in Sichuan Province. Five endemic townships were sampled from each county (district), and 100 Grade 4 to 6 students in each primary school and 100 Grade 1 to 3 students in each secondary school were sampled from each township as the study subjects. The health-related behaviors for schistosomiasis prevention and control were investigated using a questionnaire survey, and factors affecting infested water contact behaviors were identified using univariate and multilevel logistic analyses.

RESULTS

Among the 62 200 questionnaires distributed, there were 59 134 recovered, and 56 510 were qualified. The qualified 56 510 respondents included 22 955 secondary school students and 33 555 primary school students, and 28 297 male students and 28 213 females. A higher proportion of infested water contacts was seen in male students than in females (P < 0.001), and the students living in heavily endemic areas had a higher proportion of infested water contacts than those in mildly endemic areas (P < 0.001). In addition, there was no significant difference in the proportion of infested water contacts between primary and secondary school students (P >0.05). Multilevel and multivariate logistic analyses revealed a lower proportion of infested water contacts with the increase of knowledge, belief and self-efficacy levels (P < 0.001), and there was a cluster of infested water contacts among students at a county scale (P < 0.001).

CONCLUSIONS

There is a cluster of infested-water contact behaviors among primary and secondary school students at a county scale in Sichuan Province. Individual and environmental factors should be considered during the formulation of health education strategy and interventions for schistosomiasis among primary and secondary school students.

Non-ambulatory dogs with cervical intervertebral disc herniation: single versus multiple ventral slot decompression

OBJECTIVE

To evaluate the proportion of non-ambulatory dogs with cervical intervertebral disc herniation (IVDH) in a private clinic and to compare signalment and outcome between those that underwent single or multiple ventral slot decompression (VSD).

DESIGN

Retrospective cohort study.

METHODS

After screening 43,378 medical records (January 2010-September 2016), those of 185 dogs with non-ambulatory tetraparesis or tetraplegia along with cervical IVDH that had undergone single (123) or multiple (62) VSD were included in this study. Data on signalment, preoperative neurological status, location of affected intervertebral disc(s), time to ambulation and short-term outcome were compared between single and multiple VSD groups.

RESULTS

The proportion of non-ambulatory dogs with IVDH was 35.3%. The prevalence of non-ambulation was higher in male dogs (0.56%) than in female dogs (0.26%; P < 0.001) and in neutered dogs than in unneutered dogs (0.51% and 0.27%, respectively, P < 0.001). After surgery, 96.2% of the dogs reached ambulatory status. Dogs with multiple IVDH were older than those with single IVDH. Sex, neutering status or size did not affect the outcome or ambulation status postsurgery. The Pekingese was the most commonly affected breed in both groups. There was no difference in the time to reach ambulation and the presence of neurological deficits after surgery between dogs that underwent single and multiple VSD.

CONCLUSIONS

In this cohort, dogs undergoing multiple VSD had a good postoperative outcome, and their short-term functional recovery was equal to that of dogs undergoing single ventral slot compression.

Hydrophobic SiC@C Nanowire Foam with Broad-Band and Mechanically Controlled Electromagnetic Wave Absorption

With the booming of modern information technology, electromagnetic wave (EMW) absorption materials are playing more and more crucial roles in applications ranging from wearable smart electronics to national defense security. However, the application of present EMW absorption materials is severely hindered by their drawbacks, such as narrow absorption bandwidth and low absorption intensity. In this work, a series of highly porous and well-interconnected SiC@C nanowire foams (SCNFs) are rationally designed to exhibit modified impedance match and multiscale EMW energy dissipation mechanisms. The SCNF with a density of 108 mg cm^-3 realizes a broad absorption bandwidth covering the whole X and Ku bands with an intensity of -52.5 dB. The SCNF with a density of 36 mg cm^-3 and a thickness of 9.6 mm exhibits a mechanically controlled absorption band ranging from 2.9 to 18 GHz (covering over 93% of the entire radar band, 2-18 GHz) with a minimum intensity of -46 dB by simply applying a reversible compressive strain from 0 to 66.7%. Moreover, the special microstructure of SCNF also endows it with excellent hydrophobicity, which enables its good self-cleaning property. These encouraging achievements pave the way to the development of the continuous network microstructure of absorbents with a broad-band and tunable EMW absorption property.