3-D real-time ultrasound tracking of acoustically actuated swimming microdrone

Maneuverable microswimmers/microdrones that navigate in hard-to-reach spaces inside human bodies hold a great potential for various biomedical applications. Acoustically actuated microswimmers have already demonstrated feasibility. However, for eventual translation of this technology, a robust 3-D tracking strategy for the microswimmer is particularly required. This paper presents our lab-designed 3-D ultrasound tracking system for real-time tracking of an acoustically actuated 3-D swimming microdrone. The ultrasound tracking system utilizing two ultrasound probes, a step motor and a host controller, was built to track the 3-D arbitrary motion of the microdrone in real-time. The performance of tracking was evaluated in the benchtop experiments by comparing the reconstructed trajectories with synchronized camera recordings. The ultrasound tracking system showed high reliability, with an average error of less than 0.3 mm across six different trials when compared to camera tracking. The results demonstrated the capability of our lab-designed 3-D ultrasound tracking system in accurately tracking the undetermined motion of the acoustic actuated 3-D swimming microdrone in real-time. The developed tracking system holds promise as a potential approach for biomedical applications and could pave the way for future clinical translation of the microswimmer technology.

Lilium Gray Mold Suppression Conferred by the Host Antimicrobial Protein LsGRP1 Involves Main Pathogen-Targeted Manipulation of the Nonantimicrobial Region LsGRP1N

Antimicrobial protein LsGRP1 protects Lilium from gray mold mainly caused by the destructive pathogen Botrytis elliptica; however, its nonantimicrobial region LsGRP1N conversely promotes spore germination of this fungus. By assaying the effects of LsGRP1N, LsGRP1, and the combination of LsGRP1N and the antimicrobial region LsGRP1C on fungal spore germination, hyphal growth, and Lilium gray mold development, LsGRP1N was found to improve the LsGRP1C sensitivity of B. elliptica and disease suppression by LsGRP1C. B. elliptica cell vitality assays indicated that LsGRP1N pretreatment uniquely enhanced the lethal efficiency of LsGRP1C compared to the control peptides. In addition, LsGRP1N-treated B. elliptica was demonstrated to lower infection-related gene expression and increase host-defense-eliciting activity, as indicated by reverse transcription quantitative polymerase chain reaction and histochemical-staining-based callose detection results, respectively. Therefore, LsGRP1N showed a novel mode of action for antimicrobial proteins by manipulating the main pathogen, which facilitated the development of target-specific and dormant microbe-eradicating antimicrobial agents.

[Research progress on the role of adipose-derived stem cell exosomes in skin scar formation]

The adipose-derived stem cell exosomes are subcellular structures of adipose stem cells. They are nano-sized membrane vesicles that can transport various cell components and act on target cells by paracrine, and they play an important role in the exchanges of substance and information between cells. Scar healing is the commonest way of healing after skin tissue injury. Pathological scar can not only cause movement dysfunction, but also lead to deformity, which affects the appearance of patients and brings life and mental pressure to the patients. In recent years, many researches have shown that the adipose-derived stem cell exosomes contain a variety of bioactive molecules, which play an important role in reducing scar formation and scar-free wound healing, by affecting the proliferation and migration of fibroblasts and the composition of extracellular matrix. This article reviewed the recent literature on the roles and mechanisms of adipose-derived stem cell exosomes in scar formation, and prospected the future application and development of adipose-derived stem cell exosomes in scar treatment.

[A retrospective controlled study on the treatment effect of distraction osteogenesis and maxillomandibular advancement for severe obstructive sleep apnea hypopnea syndrome patients]

Objective: To compare the treatment effect of distraction osteogenesis (DO) and maxillomandibular advancement (MMA) for severe obstructive sleep apnea hypopnea syndrome (OSAHS) patients and to guide clinical decisions about treatment of OSAHS. Methods: Thirty-seven OSAHS patients which accepted maxillomandibular advancement (MMA) or distraction osteogenesis (DO) in Stomatological Hospital of the Department of Maxillofacial Trauma and Orthognathic Surgery, School of Stomatology, The Forth Military Medical University from June 2017 to June 2019 were collected. Their preoperative and postoperative data of cephalometry, polysomnography (PSG), Pittsburgh sleep quality index (PSQI) and Epworth sleepiness scale (ESS) scores were collected and analyzed. With propensity score matching method, the treatment effect of MMA and DO was analyzed and compared. Results: According to the statistics of MMA group, only AHI was correlated with operative successful rate and cure rate. With the increase of AHI, the treatment effect of MMA on OSAHS patients gradually decreased. The cut-off point of AHI as a predictor of MMA treatment failure was 78.2 n/h. All the matched cases were severe OSAHS patients. Statistical analysis showed that the mandibular elongation of DO patients[(24.00±4.39) mm] was significantly more than that of MMA group [(11.20±1.37) mm] (t=-6.11, P<0.001), the improvement of PSG index [including lowest oxygen saturation (LSpO₂), longest apnea (LA) and longest hypopnea (LH)] in DO group [LSpO₂=(93.40±1.82)%; LA=(18.28±8.32) s; LH=(61.84±32.94) s] was significantly higher than that in the MMA group [LSpO₂=(86.00±4.06)%, LA=(64.08±21.78) s, LH=(172.40±30.70) s](t=-3.72, P=0.005; t=4.39, P=0.003; t=5.49, P=0.004). The PSQI and the ESS scores of DO group (PSQI=4.20±0.83; ESS=3.40±1.52) were also significantly better than that of MMA group (PSQI=8.80±2.39, ESS=9.40±2.88)(t=4.07, P=0.001; t=4.12, P=0.002). Conclusions: For severe OSAHS patients, the objective and subjective indicators of DO treatment group showed a better therapeutic effect than that of MMA.

3-D swimming microdrone powered by acoustic bubbles

Mobile microrobots that maneuver in liquid environments and navigate inside the human body have drawn a great interest due to their possibility for medical uses serving as an in vivo cargo. For this system, the effective self-propelling method, which should be powered wirelessly and controllable in 3-D space, is of paramount importance. This article describes a bubble-powered swimming microdrone that can navigate in 3-D space in a controlled manner. To enable 3-D propulsion with steering capability, air bubbles of three lengths are trapped in microtubes that are embedded and three-dimensionally aligned inside the drone body using two-photon polymerization. These bubbles can generate on-demand 3-D propulsion through microstreaming when they are selectively excited at their individual resonance frequencies that depend on the bubble sizes. In order to equip the drone with highly stable maneuverability, a non-uniform mass distribution of the drone body is carefully designed to spontaneously restore the drone to the upright position from disturbances. A mathematical model of the restoration mechanism is developed to predict the restoration behavior showing a good agreement with the experimental data. The present swimming microdrone potentially lends itself to a robust 3-D maneuverable microscale mobile cargo navigating in vitro and in vivo for biomedical applications.

Electrocatalytic Reduction of CO2 to Methanol by Iron Tetradentate Phosphine Complex Through Amidation Strategy

The iron complex of tetradentate tris[2-(diphenylphosphino) ethyl]phosphine (PP₃ ), [Fe(PP₃ )(MeCN)₂ ](BF₄ )₂ , was able to electrocatalytically reduce CO₂ to formate with a Faradaic efficiency (FE) of approximately 97.3 % in acetonitrile. Upon addition of diethylamine as a cocatalyst, electrocatalytic reduction to methanol was achieved with an FE of 68.5 %, and other products were formamide and formate. A mechanistic study suggested that the [FeH(PP₃ )](BF₄ ) hydride complex was the active species in the electrocatalysis. Added amine as cocatalyst could react with CO₂ to form carbamate, which could then be reduced to formamide and further to methanol. By contrast, free CO₂ could only be reduced to formate as the end-product.

Cobalt Complex with Redox-Active Imino Bipyridyl Ligand for Electrocatalytic Reduction of Carbon Dioxide to Formate

An imino bipyridine cobalt(II) complex was developed for the electrocatalytic reduction of CO₂ to formate in acetonitrile with a faradaic efficiency of approximately 80 %. For comparison, a symmetric bis-imino pyridine complex showed lower catalytic activity because of less conjugation in the system. Cyclic voltammetry, electron paramagnetic resonance and IR spectroscopy studies provided mechanistic details and the structures of the key intermediates. DFT calculations confirmed the role of large π-conjugated groups for stabilizing key intermediates through electronic conjugation.

[Correlation of serum androgen levels with lipid metabolism in middle-aged and elderly men in Zunyi, Guizhou]

OBJECTIVE

To investigate the relationship of the levels of serum androgens with lipid metabolism in middle-aged and elderly men in Zunyi, Guizhou.

METHODS

Using the stratified cluster sampling method, we conducted a questionnaire investigation and physical examinations among 437 men in Zunyi City. We divided the subjects into a middle-aged (40－64 ［53.20 ± 7.41］ years, n = 269) and an elderly group (=≥65 ［70.63 ± 4.66］ years, n = 168) and collected fasting elbow venous blood samples from them for measuring the levels of total testosterone (TT), sex hormone-binding globulin (SHBG), luteinizing hormone (LH), total cholesterol (TCH), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), calculated free testosterone (cFT), free testosterone index (FTI), and testosterone secretion index (TSI).

RESULTS

Compared with the elderly group, the middle-aged males showed significantly lower SHBG, LH, HDL and LDL, and higher cFT, FTI, TSI, TG and TCH (all P < 0.05). TT and SHBG were negatively correlated with TG, TCH, HDL and LDL, while cFT was positively correlated with TCH, and so was FTI with TG, TCH with LDL, and TSI with TCH, HDL and LDL (all P < 0.05), but LH was negatively correlated with TG, TCH and LDL (all P < 0.05). Multivariate linear regression analysis showed that TT and SHBG were negatively correlated with TG, TCH, HDL and LDL, and so was LH with TCH, HDL and LDL (all P < 0.05).

CONCLUSIONS

In the middle-aged and elderly men in Zunyi, low concentrations of TT, SHBG and LH were associated with the increased risk of high-TCH and -LDL dyslipidemia, low concentrations of TT and SHBG with that of high-TG dyslipidemia, while high concentrations of TT, SHBG and LH with that of low-HDL dyslipidemia.

Correction to: Prokaryotic expression and action mechanism of antimicrobial LsGRP1C recombinant protein containing a fusion partner of small ubiquitin-like modifier

The published online version contains editing mistake in Table 2. See below for the corrected Table.

Prokaryotic expression and action mechanism of antimicrobial LsGRP1C recombinant protein containing a fusion partner of small ubiquitin-like modifier

Antimicrobial peptides (AMPs) are peptides exhibiting broad-spectrum antimicrobial activities and considered as potential therapeutic agents. LsGRP1^C, a novel AMP derived from defense-related LsGRP1 protein of Lilium, was proven to inhibit kinds of bacteria and fungi via alteration of microbial membrane permeability and induction of fungal programmed cell death-like phenomena by in vitro assays using synthetic LsGRP1^C. In this study, the prokaryotic production of LsGRP1^C recombinant protein containing an N-terminal fusion partner of the yeast small ubiquitin-like modifier (SUMO) was achieved by using optimized Escherichia coli host and purification buffer system, which lead to a high yield of soluble SUMO-LsGRP1^C fusion protein. In vitro assay revealed that E. coli-expressed SUMO-LsGRP1^C exhibited even better antifungal activity as compared to synthetic LsGRP1^C. Meanwhile, the ability of SUMO-LsGRP1^C in conducting fungal membrane permeabilization and programmed cell death was verified by SYTOX Green staining and 4',6-diamidino-2-phenylindole staining/terminal deoxynucleotidyl transferase dUTP nick-end labeling assays, respectively, indicating that E. coli-expressed SUMO-LsGRP1^C shares identical modes of action with synthetic LsGRP1^C. Herein, this E. coli expression system enables the effective and convenient production of antimicrobial LsGRP1^C in a form of SUMO-fused recombinant protein.

[Shi Weishan, the pioneer of the western medicine in Hubei in the Late Qing Dynasty]

The Englishman Shi Weishan (Frederick Porter Smith) is the first Christianity medical missionary sent to Central China, who is also the founder of the first mission hospital named 'Hospital of Universal Love' in Hubei. Arrived at Hankou in May 1864, he started medical work in July, and left Hankou in December 1870 because of health problem. In addition to medical mission, he tried to communicate with Chinese doctors in Hankou, then enlightened local people with health knowledge by written several books and articles, which brought some success. He also devoted to the translation of Chinese proper names and also wrote related book.

[Vasectomy has no obvious longterm influence on the levels of serum androgens in aging males]

OBJECTIVE

To explore the longterm influence of vasectomy on the levels of serum androgens in aging males.

METHODS

Using stratified random sampling, we conducted a questionnaire survey and physical examinations among 437 adult males aged ≥40 years, 232 with and 205 without the history of vasectomy. In addition, we measured the levels of serum total testosterone (TT), sexhormone binding globulin (SHBG), calculated free testosterone (cFT), testosterone secreting index (TSI), free testosterone index (FTI), and luteinizing hormone (LH).

RESULTS

Compared with the nonvasectomy group, the vasectomy group showed significantly increased levels of serum TT (［16.01±5.41］ vs ［17.39±6.57］ nmol/L), SHBG (［58.91±36.89］ vs ［70.28±40.90］ nmol/L), and LH (［8.86±6.49］ vs ［10.85±11.73］ IU/L) (all P< 0.05) and a decreased level of FTI (0.33±0.15 vs 0.30±0.12, P< 0.05). There were no statistically significant differences between the nonvasectomy and vasectomy groups in cFT (［0.24±0.07］ vs ［0.23±0.09］ nmol/L) or TSI (［2.42±1.34］ vs ［2.46±1.51］ nmol/IU) (both P>0.05), nor after adjustment for relevant factors in TT (β: 1.015, 95% CI: －0.180－2.210), SHBG (β: 5.118, 95% CI: －2.069－12.305), cFT (β: 0.003, 95% CI: －0.011－0.018), FTI (β: －0.012, 95% CI: －0.035－0.011), TSI (β: 0.138, 95% CI: －0.131－0.407), and LH (β: 1.011, 95% CI: －0.811－2.834) (all P>0.05).

CONCLUSIONS

Vasectomy has no obvious longterm influence on the levels of serum androgens in aging males.

Efficient SNP Discovery by Combining Microarray and Lab-on-a-Chip Data for Animal Breeding and Selection

The genetic markers associated with economic traits have been widely explored for animal breeding. Among these markers, single-nucleotide polymorphism (SNPs) are gradually becoming a prevalent and effective evaluation tool. Since SNPs only focus on the genetic sequences of interest, it thereby reduces the evaluation time and cost. Compared to traditional approaches, SNP genotyping techniques incorporate informative genetic background, improve the breeding prediction accuracy and acquiesce breeding quality on the farm. This article therefore reviews the typical procedures of animal breeding using SNPs and the current status of related techniques. The associated SNP information and genotyping techniques, including microarray and Lab-on-a-Chip based platforms, along with their potential are highlighted. Examples in pig and poultry with different SNP loci linked to high economic trait values are given. The recommendations for utilizing SNP genotyping in nimal breeding are summarized.

Racial disparities and patterns of ovarian cancer surgical care in California

OBJECTIVE

To investigate disparities in the frequency of ovarian cancer-related surgical procedures and access to high-volume surgical providers among women undergoing initial surgery for ovarian cancer according to race.

METHODS

The California Office of Statewide Health Planning and Development database was accessed for women undergoing a surgical procedure that included oophorectomy for a malignant ovarian neoplasm between 1/1/06 and 12/31/10. Multivariate logistic regression analyses were used to evaluate differences in the odds of selected surgical procedures and access to high-volume centers (hospitals ≥ 20 cases/year) according to racial classification.

RESULTS

A total of 7933 patients were identified: White = 5095 (64.2%), Black = 290 (3.7%), Hispanic/Latino = 1400 (17.7%), Asian/Pacific Islander = 836 (10.5%) and other = 312 (3.9%). White patients served as reference for all comparisons. All minority groups were significantly younger (Black mean age 57.7 years, Hispanic 53.2 years, Asian 54.5 years vs. 61.1 years, p < 0.01). Hispanic patients had lower odds of obtaining care at a high-volume center (adjusted OR (adj. OR) = 0.72, 95% CI = 0.64-0.82, p < 0.01) and a lower likelihood of lymphadenectomy (adj. OR = 0.80, 95% CI=0.70-0.91, p<0.01), bowel resection (adj. OR = 0.80, 95% CI = 0.71-0.91, p < 0.01), and peritoneal biopsy/omentectomy (adj. OR = 0.69, 95% CI = 0.58-0.82, p<0.01). Black racial classification was associated with a lower likelihood of lymphadenectomy (adj. OR = 0.76, 95% CI = 0.59-0.97, p = 0.03).

CONCLUSIONS

Among women undergoing initial surgery for ovarian cancer, Hispanic patients are significantly less likely to be operated on at a high-volume center, and both Black and Hispanic patients are significantly less likely to undergo important ovarian cancer-specific surgical procedures compared to White patients.

[Roles of calcitonin gene-related peptide family in pain and opioid tolerance]

The calcitonin gene-related peptide (CGRP) family mainly includes CGRPα, CGRPβ, adrenomedullin, calcitonin and amylin. The members of CGRP family and their receptors are widely distributed in the central and peripheral nervous systems. Studies show that members of CGRP family such as CGRP and adrenomedullin play important roles in the transmission of nociceptive information. At spinal level, CGRP promotes the transmission of nociceptive information, spinal morphine tolerance, migraine, inflammatory pain and neuropathic pain. At superspinal level, CGRP suppresses the transmission of nociceptive information. Adrenomedullin is a pain-related neuropeptide which has recently been demonstrated. It facilitates the transmission of nociceptive information and is involved in the development and maintenance of opioid tolerance. The involvement of amylin and calcitonin in pain is not clear yet.

Disparities in uterine cancer epidemiology, treatment, and survival among African Americans in the United States

OBJECTIVE

The objective of this article is to comprehensively review the scientific literature and summarize the available data regarding the outcome disparities of African American women with uterine cancer.

METHODS

Literature on disparities in uterine cancer was systematically reviewed using the PubMed search engine. Articles from 1992 to 2012 written in English were reviewed. Search terms included endometrial cancer, uterine cancer, racial disparities, and African American.

RESULTS

Twenty-four original research articles with a total of 366,299 cases of endometrial cancer (337,597 Caucasian and 28,702 African American) were included. Compared to Caucasian women, African American women comprise 7% of new endometrial cancer cases, while accounting for approximately 14% of endometrial cancer deaths. They are diagnosed with later stage, higher-grade disease, and poorer prognostic histologic types compared to their Caucasian counterparts. They also suffer worse outcomes at every stage, grade, and for every histologic type. The cause of increased mortality is multifactorial. African American and white women have varying incidence of comorbid conditions, genetic susceptibility to malignancy, access to care and health coverage, and socioeconomic status; however, the most consistent contributors to incidence and mortality disparities are histology and socioeconomics. More robust genetic and molecular profile studies are in development to further explain histologic differences.

CONCLUSIONS

Current studies suggest that histologic and socioeconomic factors explain much of the disparity in endometrial cancer incidence and mortality between white and African American patients. Treatment factors likely contributed historically to differences in mortality; however, studies suggest most women now receive equal care. Molecular differences may be an important factor to explain the racial inequities. Coupled with a sustained commitment to increasing access to appropriate care, on-going research in biologic mechanisms underlying histopathologic differences will help address and reduce the number of African American women who disproportionately suffer and die from endometrial malignancy.

Stationary headband for clinical time-of-flight optical imaging at the bedside

Conventional brain-imaging modalities may be limited by high cost, difficulty of bedside use, noncontinuous operation, invasiveness or an inability to obtain measurements of tissue function, such as oxygenation during stroke. Our goal was to develop a bedside clinical device able to generate continuous, noninvasive, tomographic images of the brain using low-power nonionizing optical radiation. We modified an existing stage-based time-of-flight optical tomography system to allow imaging of patients under clinical conditions. First, a stationary head-band consisting of thin, flexible optical fibers was constructed. The headband was then calibrated and tested, including an assessment of fiber lengths, the existing system software was modified to collect headband data and to perform simultaneous collection of data and image reconstruction, and the existing hardware was modified to scan optically using this headband. The headband was tested on resin models and allowed for the generation of tomographic images in vitro; the headband was tested on critically ill infants and allowed for optical tomographic images of the neonatal brain to be obtained in vivo.

Long-term effect of leprosy control in two Prefectures of China, 1955-1993

In Weifang Prefecture, Shandong Province, and Wenshan Prefecture, Yunnan Province of China, leprosy was highly prevalent in the 1950s. Due to differences in geographical conditions and socioeconomic development, the decline in leprosy prevalence between 1955 and 1993 was 99.5% (10.1 to 0.05/10,000) in Weifang and 93.9% (19.7 to 1.2/10,000) in Wenshan. The decrease in the detection rate was 99.9% (35.2 to 0.05/10,000) in Weifang and 91.7% (69.9 to 5.8/10,000) in Wenshan. The decrease was more apparent in these two prefectures since the implementation of multidrug therapy (MDT) in 1986. Findings such as specific detection rates by age, sex and type, as well as the multibacillary, child, and deformity rates of patients detected since 1980 were studied. Using the detection and prevalence rates between 1980 and 1993, the number of patients until the year 2000 is extrapolated for these two prefectures.