Subpolar North Atlantic western boundary density anomalies and the Meridional Overturning Circulation

Changes in the Atlantic Meridional Overturning Circulation, which have the potential to drive societally-important climate impacts, have traditionally been linked to the strength of deep water formation in the subpolar North Atlantic. Yet there is neither clear observational evidence nor agreement among models about how changes in deep water formation influence overturning. Here, we use data from a trans-basin mooring array (OSNAP-Overturning in the Subpolar North Atlantic Program) to show that winter convection during 2014-2018 in the interior basin had minimal impact on density changes in the deep western boundary currents in the subpolar basins. Contrary to previous modeling studies, we find no discernable relationship between western boundary changes and subpolar overturning variability over the observational time scales. Our results require a reconsideration of the notion of deep western boundary changes representing overturning characteristics, with implications for constraining the source of overturning variability within and downstream of the subpolar region.

KIF2A regulates ovarian development via modulating cell cycle progression and vitollogenin levels

The kinesin superfamily of proteins (KIFs) are microtubule motor proteins that use the hydrolysis of ATP to power directional movement along microtubules. KIFs induce microtubule depolymerization to regulate the length and dynamics of microtubules in a variety of cell processes and structures, including the mitotic and meiotic spindles and centriole and interphase microtubules. KIF plays a significant role in the transport of organelles, protein complexes and mRNAs. The brown planthopper (Nilaparvata lugens) is a major insect pest in rice paddy fields. Ovarian development is regulated by multiple factors, including endocrine factors. The role of KIFs in brown planthopper ovarian development remains unknown. We found that downregulation of KIF2A significantly compromised the development and eclosion of the brown planthopper, delayed ovarian cell cycle progression, disrupted ovarian development, reduced the expression of MCM genes required for DNA replication and significantly reduced the number of nuclei in the follicles. We also found a significant reduction in Vg mRNA and protein levels. We conclude that downregulation of KIF2A disrupts the cell cycle progression of cells. Alternatively, the ovarian phenotype could be an indirect effect of a compromised trophic cord. In summary, KIF2A regulates ovarian development via modulating cell cycle progression and/or vitollogenin transportation.

High expression of ACE2 in the human lung leads to the release of IL6 by suppressing cellular immunity: IL6 plays a key role in COVID-19

OBJECTIVE

The pathogenesis of coronavirus disease 2019 (COVID-19) remains clear, and no effective treatment exists. SARS-CoV-2 is the virus that causes COVID-19 and uses ACE2 as a cell receptor to invade human cells. Therefore, ACE2 is a key factor to analyze the SARS-CoV-2 infection mechanism.

MATERIALS AND METHODS

We included 9,783 sequencing results of different organs, analyzed the effects of different ACE2 expression patterns in organs and immune regulation.

RESULTS

We found that ACE2 expression was significantly increased in the lungs and digestive tract. The cellular immunity of individuals with elevated ACE2 expression is activated, whereas humoral immunity is dampened, leading to the release of many inflammatory factors dominated by IL6. Furthermore, by studying the sequencing results of SARS-CoV-2-infected and uninfected cells, IL6 was found to be an indicator of a significant increase in the number of infected cells. However, although patients with high expression of ACE2 will release many inflammatory factors dominated by IL6, cellular immunity in the colorectum is significantly activated. This effect may explain why individuals with SARS-CoV-2 infection have severe lung symptoms and digestion issues, which are important causes of milder symptoms.

CONCLUSIONS

This finding indicates that ACE2 and IL6 inhibitors have important value in COVID-19.

Screening and evaluation of Monascus purpureus FJMR24 for enhancing the raw material utilization rate in rice wine brewing

BACKGROUND

The rapid development of the rice wine industry has increased the demand for raw materials worldwide. A fungal strain with good adaptability to rice wine brewing conditions, which can also enhance the utilization rate of raw materials (URRM), thus increasing the production efficiency, was sought in the present research.

RESULTS

The strain FJMR24 was successfully isolated and screened from 35 fermentation starters and exhibited high amylase activity (2200.9 ± 18.5 U g^-1 ) and high glucoamylase activity (2330.4 ± 31.9 U g^-1 ). Based on a morphological examination and a sequence analysis of the internal transcribed spacer (ITS) gene and β-tubulin gene, FJMR24 was identified as Monascus purpureus, which is an edible and versatile fungus that plays a dominant role in the processing of Hong Qu. A moderate pH of 5-6 under incubation at 35 °C for 5-6 days was favorable for the growth and enzyme production of FJMR24. The strain could also tolerate the extreme conditions of 15-45 °C, 18% ethanol (v/v), and an acidity of pH 2. The excellent fermentation adaptability of FJMR24 might enable it to retain high enzyme activity during rice wine brewing. As a result of the action of FJMR24, the URRM of the base liquor increased by around 26% due to increased starch hydrolysis efficiency, which was mainly due to the high unit enzyme activity of FJMR24.

CONCLUSION

This study provides perspectives for the application of a M. purpureus strain with high starch hydrolysis activity for enhancing the URRM in traditional rice wine brewing. © 2020 Society of Chemical Industry.

Cohort Profile: West China Health and Aging Trend (WCHAT)

OBJECTIVES

The West China Health and Aging Trends study (WCHAT) is intended to focus on the research that will guide efforts to reduce disability, maximize health and independent functioning, and enhance quality of life at older ages in different ethnicities. And provide the basis for understanding trends and dynamics in late-life functioning, how these differ in various ethnic subgroups, and the economic or social consequences of aging and disability in western China.

PARTICIPANTS

The cohort enrolled 7536 participants and 7439 participants aged 50 years and older in the baseline in 2018 and every year would be followed up. Finding to date: The data in WCHAT were prospectively collected from Yunnan, Guizhou, Sichuan and Xinjiang by 7 medical institutions. A number of age-related outcome measures were collected though corresponding geriatric assessments. Blood testing, saliva, urine and feces testing are available for all cohort participants. Future plans: The data in WCHAT can be used for various types of epidemiological research, particularly for examining how the culture specific life styles and diet influences geriatrics related outcomes. We are initially planning cohort studies and established a sample biobank in relation to the risk and prognosis of frailty, sarcopenia and other geriatric syndromes. Strengths and limitations of this study: It is a first multi-ethnic cohort study in West China that aimed to investigate the influence of culture specific life styles, diet and living environment on the prevalence of geriatric syndromes like frailty, sarcopenia and so on. This is a prospective multi-center observational study, which will be conducted in various ethnic groups gathering places. This study collected information that related to fatigue, falls, and cognition were obtained through self-reports, which might have recall bias and grouping errors. This study has problems such as the interviewees' refusal to visit, death, going out, and large population mobility may lead to high loss of visit rates. This study collected information from a comparatively healthier elderly population in which external validity was limited.

Evaluation of Four Methods for the Assessment of Sarcopenia in Older Adults in Nursing Homes

OBJECTIVES

We aimed to evaluate the comparative effectiveness and applicability of using calf circumference (CC), strength, need for assistance with walking, rising from a sitting position, climbing stairs, and the incidence of falls (SARC-F), as well as SARC-F plus CC (SARC-CalF) and the Ishii test, for assessing sarcopenia in older adult nursing home occupants.

METHOD

In this cross-sectional study, the diagnostic criteria of the AWGS2019 were used as the standard, and the accuracy of the four screening methods determined by indicators, including sensitivity, specificity, receiver operating characteristic (ROC) curve, positive predictive values (PPV), and negative predictive values (NPV).

RESULTS

One hundred and ninety-nine older adults, 97 male and 102 female, were included. The prevalence of sarcopenia was 48.7%. Over all the participants, the sensitivity and specificity of CC were 74.22% and 51.96%, respectively, and 40.21% and 83.33%, respectively, for SARC-F. The use of SARC-CalF raised the SARC-F sensitivity (71.14%) while reducing the specificity (60.78%). The Ishii test had a sensitivity of 89.7% and a specificity of 74.51%. The PPV and NPV of CC, SARC-F, SARC-CalF, Ishii test were 0.6/0.68, 0.7/0.59, 0.55/0.63, and 0.77/0.88, respectively. The areas under the curve for CC, SARC-F, SARC-CalF, and the Ishii test were 0.67(95%CI, 0.59-0.74), 0.71(95%CI, 0.64-0.79), 0.71(95%CI, 0.64-0.79), and 0.86 (95% CI,0.81-0.92), respectively. The sensitivity and specificity of CC, SARC-F, SARC-CalF, and the Ishii test for sarcopenia screening in males were 71.69%/56.41%, 29.31%/79.49%, 67.24%/64.10%, and 94.83%/56.41%, respectively, and in females were 79.49%/49.21%, 56.41%/85.71%, 76.92%/58.73%, and 82.05%/85.71%, respectively. The PPV and NPV of CC, SARC-F, SARC-CalF, and the Ishii test in males were 0.71/0.56, 0.68/0.43, 0.74/0.57, and 0.76/0.88, respectively, while in females the values were 0.49/0.79, 0.71/0.76, 0.54/0.8, and 0.78/0.89, respectively.The areas under the curve for CC, SARC-F, SARC-CalF, and the Ishii test in males were 0.7(95%CI, 0.59-0.8), 0.63(95%CI, 0.52-0.75), 0.68(95%CI, 0.57-0.8), and 0.86(95% CI, 0.78-0.94), respectively, and in females 0.69(95%CI, 0.58-0.8), 0.81(95%CI, 0.72-0.89), 0.76(95%CI, 0.67-0.86), and 0.85 (95%CI, 0.77-0.94), respectively.

CONCLUSION

The overall screening ability of the Ishii test for sarcopenia was superior to that of the CC, SARC-F, and SARC-CalF in older adults in nursing homes.

Physiological effects of transport duration on stress biomarkers and meat quality of medium-growing Yellow broiler chickens

Pre-slaughter transport exerts negative effects on broilers' welfare, meat yield, and meat quality, but little is known about the effect of transport on medium-growing broiler chickens. This study aimed at evaluating the effects of different durations of transport (0, 0.5, 1, 2, and 3h) on stress biomarkers and meat quality of medium-growing Yellow-feathered broiler chickens. One hundred and eighty Chinese Yellow-feathered broilers aged 75days (marketing age), of 2.02kg average BW, were allotted into five groups; each group contained six replicates (six birds/replicate (crate)). Each crate with dimensions 74×55×27cm (length × width × height) was loaded with six birds, that is, 30kg live BW/m² crate. The tested transport durations increased BW loss (linear, P<0.01), plasma concentrations of ACTH (linear, P<0.10), cortisol and corticosterone (quadratic, P<0.05), and activity of glutathione peroxidase (linear, P<0.05), whereas plasma glucose was not affected. In breast muscle, contents of glycogen, lactic acid, malondialdehyde, and reduced glutathione were not affected (P>0.05), but total antioxidant capacity decreased (linear, P<0.01). The drip loss of breast muscle increased (linear, P<0.01), whereas shear force, pH at 24h postmortem, and breast meat color lightness (L*), redness (a*), and yellowness (b*) scores were not affected. In conclusion, the tested transport durations (from 0.5 to 3h) increased BW loss and some plasma stress biomarkers in 75-day-old Yellow-feathered broiler chickens, but the effect on meat quality attributes was minor.

Effect of Liposome-Encapsulated Zoledronic Acid on Microenvironment of Hepatocellular Carcinoma May Depend on the Ratio Between M1 and M2 Polarized Macrophages

We studied the effect of zoledronic acid encapsulated into liposomes (L-ZOL) on tumorassociated macrophages in the stroma of hepatocellular carcinoma xenograft. Liposomes were prepared from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, 1,2-dipalmitoyl-snglycero-3-phospho-sn-1-glycerol, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[carboxy(polyethylene glycol)-2000] using thin film method and loaded with zoledronic acid. It was shown that L-ZOL promoted apoptosis of RAW264.7 cells, eliminate much more protumoral M2 macrophages than antitumoral M1 macrophages in the tumor xenograft, and did not significantly reduce the size of xenograft in 6 days. Thus, the effect of treatment depends on the ratio between antitumoral M1 and protumoral M2 polarized macrophages in the tumor.

[Application of two-stage crestal approach sinus elevation in severe atrophic posterior maxilla]

Objective: To investigate the feasibility of two-stage crestal approach sinus elevation in severe atrophic maxilla. Methods: A total of 25 patients (male: 13 cases,female: 12 cases) who attended Department of Implant Center, Stomatological Hospital, Southern Medical University from May 2016 to May 2018 were included in this study. The age of the patients was 32-49 years old. The inclusion criteria were: single or multiple tooth loss in posterior maxilla with residual bone height ranged from 1.5 to 3.0 mm and vertical bone width≥6 mm, no pathological changes or septum were detected in the sinus. The elevated sides were divided into three groups according to different buccal-palatal sinus width (SW): wide (16 case, SW＞15 mm), normal (12 case, 12 mm≤SW≤15 mm), narrow (5 case, SW<12 mm). Finally, 23 patients with 33 implants were placed by the two-stage crestal approach for sinus elevation. Six months after implant placement, final restorations were delivered. Implant survival rate, implant stability quotient (ISQ), immediate vertical bone height (VBH) after surgeries, changes of sinus elevation height (cSEH), marginal bone loss (MBL) at 1 year follow-up were examined. Results: Twenty-three patients were finally included in the study, including 12 males and 11 females, aged (41.2±7.6) years old. All implants healed uneventfully. ISQ (wide: 50.81±2.69; normal: 60.58±2.54; narrow: 63.12±3.58), immediate VBH after 1st surgery [wide: (7.99±1.13) mm; normal: (8.95±0.81) mm; narrow: (9.18±0.90) mm] and 2nd surgery [wide: (11.46±0.88) mm; normal: (12.77±0.49) mm; narrow: (12.57±0.55) mm], cSEH six months after 1st [wide: (3.87±0.43) mm; normal: (2.01±0.65) mm; narrow: (1.49±0.33) mm] and 2nd [wide: (1.16±0.29) mm; normal: (1.04±0.33) mm ; narrow: (0.97±0.41) mm] surgery, MBL [wide: (0.91±0.05) mm; normal: (0.79±0.10) mm; narrow: (0.74±0.07) mm] were significantly different among three groups (P<0.05). In all the three groups, cSEH was barely detected at 1-year follow-up (P>0.05). Conclusions: Two-stage crestal approach for sinus elevation might be an alternative protocol in severe atrophic posterior maxilla, especially in cases with narrow and normal buccal-palatal width. There is an urgent need for long time follow-up and more clinical cases.

[Application of digital technique aided occlusal rehabilitation in implant-supported fixed prosthesis of fully edentulous patients]

Objective: To evaluate the clinical outcomes of digital technique-aided occlusal rehabilitation based on implant-supported fixed prostheses (ISFP), and to provide some information for clinical application of digital technique. Methods: Retrospectively reviewed the cases which had used neuromuscular system and condylar movement tracing device to reconstruct occlusion in one or double jaw fully edentulous ISFP from January, 2013 to January, 2020. A total of 6 eligible patients were enrolled in the present study with 56 implants and 8 ISFP, including 4 male patients and 2 female patients, aged from 43 to 74 years. The clinical outcomes were evaluated in four aspects, including implant survival rate, implants success rate, marginal bone loss and the occurrence of prosthesis complications. Results: The follow-up time was (4.0±2.2) years (1-7 years). The implant survival rate was 100% (56/56) and the implant success rate was 98% (55/56), with an average missal and distal marginal bone loss of (0.04±0.11) mm/year. Veneer chipping occurred at incisal edge of 2 adjacent incisors in only one prosthesis 3 years after rehabilitation. Conclusions: Combination of digital techniques of neuromuscular system and condylar movement tracing device to assist occlusal rehabilitation based on ISFP showed a high implant success rate. The complication seldom happened. Long and stable occlusion has been observed. The clinical outcomes were favorable.

Genomic epidemiology of Corynebacterium striatum from three regions of China: an emerging national nosocomial epidemic

BACKGROUND

Corynebacteritum straitum has been considered as an emerging multi-drug-resistant (MDR) pathogen. Isolation of MDR C. striatum as the only organism from respiratory samples from hospitalized patients is increasing in China.

AIM

To elucidate the genomic epidemiology and evolution of C. striatum in China.

METHODS

A total of 260 isolates from 2016 to 2018 were collected from three hospitals in three regions of China. Antibiotic sensitivity testing was performed on all isolates. Whole-genome sequencing was applied to all isolates to assess their genomic diversity and relationships and detect the presence of antimicrobial resistance genes (ARG) and ARG cassettes.

FINDINGS

Almost all isolates (96.2%, 250/260) showed multi-drug-resistance. Genome sequencing revealed four major lineages with lineage IV emerging as the epidemic lineage. Most of the diversity was developed in the last 6 years. Each hospital has its own predominant clones with potential spread between Hebei and Guangdong hospitals. Genomic analysis further revealed multiple antimicrobial resistance genes.

CONCLUSIONS

Our results suggested that four lineages of C. striatum have spread in parallel across China, causing persistent and extensive transmissions within hospitals. MDR C. striatum infection has become a national epidemic. Antibiotic-driven selection pressure may have played significant roles in forming persistent and predominant clones. Our data provide the basis for surveillance and prevention strategies to control the epidemic caused by MDR C. striatum.

Research Note: Responses of growth performance, immune traits, and small intestinal morphology to dietary supplementation of chromium propionate in heat-stressed broilers

This study was conducted to investigate the dose responses of growth performance, immune traits, and small intestinal morphology to dietary supplementation of chromium propionate (CrPro) in heat-stressed broilers. A total of 252 1-day-old Cobb 500 male broilers were randomly assigned to 6 treatments with 7 replicate cages of 6 birds per cage. The dietary treatments consisted of a basal diet supplemented with 0, 0.2, 0.4, 0.8, 1.6, and 3.2 mg/kg Cr in the form of CrPro. The birds had ad libitum access to feed and tap water for an experimental period of 42 D. For induction of heat stress, the house temperature was set at 35°C ± 2°C from 22 to 42 D of age. No differences were detected among treatments in growth performance during the experimental period (P > 0.05). Serum IgA concentrations were not affected by treatment (P > 0.05). However, a quadratic response was detected for serum IgG (P < 0.01) and IgM (P < 0.01) concentration as dietary Cr supplementation was increased. The highest response of IgG and IgM in serum was observed for broilers fed a diet supplemented with 0.2 mg of Cr/kg. Dietary supplementation of Cr had no impacts on villus height, crypt depth, or the ratio of villus height to crypt depth in the jejunum and ileum. A quadratic response of villus height and the ratio of villus height to crypt depth and a linear response of crypt depth to increased dietary Cr supplementation were observed in the duodenum (P < 0.01). The results indicate that CrPro supplementation could modify the intestinal morphology of the duodenum and influence serum IgG and IgM concentrations in heat-stressed broiler chickens. Based on the results of this experiment, the 0.2-mg Cr/kg diet from CrPro increases immune response and intestinal health in heat-stressed broilers.

LncRNA HOXA-AS2 regulates microRNA-216a-5p to promote malignant progression of non-small cell lung cancer

OBJECTIVE

Previous studies have shown that long non-coding RNA (lncRNA) HOXA-AS2 is a cancer-promoting gene. However, the role of HOXA-AS2 in non-small cell lung cancer (NSCLC) has not been reported. This study aims to investigate the expression characteristics of HOXA-AS2 in NSCLC and whether HOXA-AS2 can promote the malignant progression of NSCLC by regulating microRNA-216a-5p.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to examine the HOXA-AS2 level in 40 pairs of NSCLC tumor tissue samples and adjacent ones. Then, the relationship between HOXA-AS2 expression and clinical indicators and prognosis of NSCLC was analyzed. Meanwhile, qRT-PCR further verified the expression level of HOXA-AS2 in NSCLC cell lines. Also, HOXA-AS2 knockdown and overexpression models were constructed using lentivirus in NSCLC cell lines, and the effects of HOXA-AS2 on the biological function of NSCLC cells were analyzed using the Cell Counting Kit-8 (CCK-8), transwell migration, and cell wound healing assays. Finally, Western blotting assay and cell recovery experiment were used to explore the regulatory mechanism of HOXA-AS2 and microRNA-216a-5p in NSCLC.

RESULTS

In this experiment, qRT-PCR results revealed that HOXA-AS2 level in NSCLC tumor tissue specimens was remarkably higher than that in adjacent tissues. Compared with those with low expression of HOXA-AS2, the patients with high expression had a higher incidence of distant metastases and a lower overall survival rate. The proliferative and metastasis abilities of the cells in the HOXA-AS2 overexpression group were remarkably increased when compared with the control group, while the opposite results were observed in HOXA-AS2 silence group. Subsequently, qRT-PCR verified that microRNA-216a-5p level was remarkably decreased in NSCLC tissues and negatively correlated with HOXA-AS2 expression. In addition, the result of the cell recovery experiment and Western blotting revealed that there might be a mutual regulation between HOXA-AS2 and microRNA-216a-5p, the two of which could jointly regulate the malignant progression of NSCLC.

CONCLUSIONS

The results indicate that lncRNA HOXA-AS2 is upregulated in NSCLC and is remarkably associated with distant metastasis and poor prognosis of NSCLC patients. In addition, lncRNA HOXA-AS2 is found to be able to promote the malignant progression of NSCLC via regulating microRNA-216a-5p.

Increased expression of Toll-like receptor 7 and 9 in vitiligo melanocytes: a pilot study

BACKGROUND

Toll-like receptors (TLRs) are expressed on human melanocytes, and play an important role in innate and acquired immunity. The role of TLRs in the pathogenesis of vitiligo has not been fully described.

AIM

To investigate the expression of TLRs in melanocytes from patients with vitiligo and healthy controls (HCs).

METHODS

Primary cultured vitiligo and control melanocytes were obtained from perilesional normal skin of patients with generalized vitiligo and HCs. TLRs mRNA expression in melanocytes were determined by real-time reverse transcription PCR and protein expression by western blotting. Apoptosis was analysed using an annexin V-fluorescein isothiocyanate apoptosis detection kit, and tyrosinase activity and melanin content were measured by a modified dopachrome and colorimetric method. Interleukin (IL)-6, IL-8 and soluble cell adhesion molecule (sICAM)-1 expression were measured by ELISA.

RESULTS

In vitiligo melanocytes, compared with control melanocytes, apoptosis rate, expression of TLR7 and TLR9 mRNA and protein, and production of IL-8, IL-6 and sICAM-1 were significantly increased, whereas tyrosinase activity and melanin content were significantly decreased.

CONCLUSIONS

Our results suggest that the increased expression of TLR7 and TLR9 might correlate with melanocyte dysfunction in vitiligo.

Silenced miR-21 inhibits renal interstitial fibrosis via targeting ERK1/2 signaling pathway in mice

OBJECTIVE

To study the influence of micro ribonucleic acid (miR)-21 on the renal interstitial fibrosis (RIF) model mice, and to preliminarily elucidate the mechanism of action of miR-21 in the development of RIF by studying the influences of miR-21 on the expressions of the proteins related to the extracellular signal-regulated kinase (ERK) 1/2 signaling pathway and its downstream proteins.

MATERIALS AND METHODS

The mouse model of the left unilateral ureteral obstruction (UUO) was established. The experimental mice were divided into the Sham group and UUO group and were normally fed for 3 weeks. Then, they were executed, and their blood was extracted to determine the renal function-related indicators. The left kidney was excised, and the corresponding specimens were reserved for observing the appearance of the kidney and the morphology of the renal tubules and interstitium. The relative expression levels of epithelial (E-)cadherin, α-smooth muscle actin (α-SMA), and ERK1/2 phosphorylated ERK1/2 (p-ERK1/2), the transforming growth factor-β1 (TGF-β1) and the connective tissue growth factor (CTGF) proteins in renal tissues were determined. After the human renal proximal tubular epithelial cell line, the human kidney-2 (HK-2) was treated with high glucose (HG) combined with silenced miR-21 or the ERK1/2 inhibitor PD98059, the relative expression levels of ɑ-SMA and TGF-β1 protein were measured.

RESULTS

UUO group had significantly higher content of blood urea nitrogen (BUN), serum creatinine (SCr), and uric acid (UA) than the Sham group, and exhibited the infiltration of renal interstitial monocytes and lymphocytes, renal tubular podocyte damage, phenotypic transformation and atrophy, the activation and proliferation of interstitial fibroblasts, and excessive deposition of extracellular matrix (ECM). Moreover, the expression level of E-cadherin in the renal tissues was decreased, but the relative expression levels of ɑ-SMA, and TGF-β1, CTGF, and p-ERK1/2 proteins were evidently elevated. Lower relative expression levels of ɑ-SMA and TGF-β1 protein were detected in the human renal proximal tubular epithelial cell line HK-2 after the combined treatment with HG and silenced miR-21 or the ERK1/2 inhibitor PD98059.

CONCLUSIONS

MiR-21 may be related to the occurrence and development of RIF. Silenced miR-21 probably suppresses RIF via the ERK1/2 signaling pathway.

Clinical and immunologic features among COVID-19-affected mother-infant pairs: antibodies to SARS-CoV-2 detected in breast milk

The coronavirus disease 2019 (COVID-19) pandemic remains threatening to women and children, but clinical evidence regarding women during pregnancy, puerperium and lactation is limited. We assessed clinical and immunologic features of and breastfeeding advice provided to mother–infant pairs. This observational analysis was conducted in a tertiary-care centre in Wuhan, China. Pregnant patients with laboratory-confirmed COVID-19 who delivered during hospitalization were enrolled. Clinical characteristics and serial specimens of the mother–infant pairs were examined, supplemented with follow-ups regarding recovery and breastfeeding. Fourteen pregnant patients had live births and recovered well; four patients continued breastfeeding while taking precautions. No neonatal infections were observed. No infants developed COVID-19 during breastfeeding. Common maternal symptoms were fever (11/14, 78.1%) and cough (6/14, 42.9%). A pregnancy-specific symptom was abnormal foetal movement, which was noticed by three patients (21.4%). The mean virus shedding time was 9 days (standard deviation, 6 days; range, 1–22 days). The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome was not detected in breast milk or maternal vaginal secretions. Immunologic assay revealed seroconversion of IgM on day 8 after onset and IgG on day 28. Both IgM and IgG antibodies to SARS-CoV-2 were detected in breast milk, cord blood and neonatal serum. The study results suggest that passive acquisition of antibodies against SARS-CoV-2 is available by ingesting breast milk. Breastfeeding has a low risk of transmitting SARS-CoV-2 or escalating maternal disease, so continuing breastfeeding with prudent precautions is encouraged.