Patient-Derived Xenograft: A More Standard "Avatar" Model in Preclinical Studies of Gastric Cancer

Despite advances in diagnosis and treatment, gastric cancer remains the third most common cause of cancer-related death in humans. The establishment of relevant animal models of gastric cancer is critical for further research. Due to the complexity of the tumor microenvironment and the genetic heterogeneity of gastric cancer, the commonly used preclinical animal models fail to adequately represent clinically relevant models of gastric cancer. However, patient-derived models are able to replicate as much of the original inter-tumoral and intra-tumoral heterogeneity of gastric cancer as possible, reflecting the cellular interactions of the tumor microenvironment. In addition to implanting patient tissues or primary cells into immunodeficient mouse hosts for culture, the advent of alternative hosts such as humanized mouse hosts, zebrafish hosts, and in vitro culture modalities has also facilitated the advancement of gastric cancer research. This review highlights the current status, characteristics, interfering factors, and applications of patient-derived models that have emerged as more valuable preclinical tools for studying the progression and metastasis of gastric cancer.

[A multi-center, randomized controlled study on the effect of Saccharomyces boulardii combined with triple therapy for the initial eradication of Helicobacter pylori infection]

Objective: To assess the efficacy and safety of Saccharomyces boulardii (S. boulardii) in combination with triple therapy as a first-line regimen for the eradication of Helicobacter pylori (H. pylori) in non-ulcer dyspepsia (NUD) patients. Methods: A total of 497 Helicobacter pylori-positive patients who underwent gastroscopy and diagnosed with NUD were enrolled from June 2018 to January 2020 in 9 medical centers across China. Participants were segmentedly randomly divided into 3 groups. Patients in group A received S. boulardii for 14 days and triple therapy for 10 days, while patients in group B received bismuth quadruple group for 10 days, and patients in group C received triple therapy for 10 days. The H. pylori status was determined by the ¹³C-urea breath test on the 44th day of the treatment. Symptom improvement and adverse reactions were assessed on the 14th and 44th day. Results: There were 229 males and 268 females in all 497 patients enrolled. They were aged 18-69 (46.1±11.8) years and 472 of them (158 cases in group A, 159 cases in group B, and 155 cases in group C) completed the trial. The intention-to-treat (ITT) eradication rates in patients in patients A, B and C were 77.8% (126/162), 80.1% (137/171) and 65.2% (107/164) respectively, and per protocol-based (PP) eradication rates were 79.7% (126/158), 86.2% (137/159) and 69.0% (107/155) respectively. The differences were statistically significant in ITT and PP analysis among 3 groups (ITT: χ²=11.14, P<0.01; PP: χ²=13.86, P<0.01). There was no significant difference between eradication rates of two quadruple therapys(all P>0.05), but both of them were significantly higher than that of standard triple therapy (both P<0.05). Statistics revealed that both quadruple therapys led to significantly higher symptom improvement of belching compared with that of standard triple therapy in day 14 (P<0.05). The relief of abdominal distension and belching symptom scores of group A were significantly higher than those of group C in day 44(all P<0.05). There was no serious adverse event reported. The incidence of diarrhea in group A was significantly lower than those in the other two groups (both P<0.05). Conclusions: The combination of S. boulardii and triple therapy can achieve a better eradication effect on H. pylori infection with NUD, and has advantages in symptom relief and safety.

[Progress in pulmonary enteric adenocarcinoma]

Pulmonary enteric adenocarcinoma (PEAC), as a rare histologic subtype of primary lung adenocarcinoma, is defined as an adenocarcinoma in which the enteric component exceeds 50%. It is named after its shared morphological and immunohistochemical features with colorectal cancer. While with such similarity, the differential diagnosis of PEAC and lung metastatic colorectal cancer is a great challenge in the clinic. PEAC may originate from the intestinal metaplasia of respiratory basal cells stimulated by risk factors such as smoking. Current studies have found that KRAS is a relatively high-frequency mutation gene, and other driver gene mutations are rare. In terms of immunohistochemistry, in pulmonary enteric adenocarcinoma, the positive rate was 88.2% (149/169) for CK7, 78.1% (132/169) for CDX2, 48.2% (82/170) for CK20 and 38.8% (66/170) for TTF1. As for clinical features, the average age of onset for pulmonary enteric adenocarcinoma was 62 years, male patients accounted for 56.5% (35/62), smokers accounted for 78.8% (41/52), and 41.4% (24/58) of the primary lesion was located in the upper lobe of the right lung. In terms of treatment, conventional non-small cell lung cancer (NSCLC) regimens rather than colorectal cancer regimens are now recommended. There is still an urgent need for more basic and clinical research, in-depth exploration of its molecular feature and pathogenesis from the level of omics and other aspects, to help diagnosis and differential diagnosis, and find the optimal chemotherapy regimen, possibly effective targeted therapy and even immunotherapy.

Risk factors of herpes simplex virus reactivation after surgery for primary trigeminal neuralgia

The objective of this study is to investigate the risk factors of oral or facial herpes simplex virus (HSV-1) infection after primary trigeminal neuralgia (PTN). The clinical data of 33 PTN patients admitted by the same surgeon in the neurosurgery were retrospectively analyzed. Among the 33 patients, 26 patients underwent microvascular decompression (MVD), 6 patients who have not been found the clear offending vessels during the operation underwent partial sensory rhizotomy (PSR), and only one underwent adhesive band separation. Thirteen patients with postoperative oral and facial HSV-1 infection were selected as the herpes group, and the remaining 20 patients without postoperative oral and facial HSV-1 infection were selected as the non-herpes group. The differences between the two groups were compared by statistical analysis of factors such as gender, age, operation mode, operation time, and serum HSV-1 antibody titer value before surgery. Compared with the non-herpes group, there were no statistically significant differences in sex ratio (P = 0.930), age composition (P = 0.261), or disease profile (P = 0.226). Twenty-six patients underwent MVD operation, eight of whom were infected, and the difference between the two groups was statistically significant (P = 0.029). The operation time of the herpes group was 10-30 min, which was significantly longer than that of the non-herpes group. The difference in operation time between the two groups was statistically significant (P = 0.023). Serum HSV-1-IgM was negative (< 0.9 COI) in all patients before surgery, but the positive rate of HSV-1-IgG (≥ 1.1 COI) was 97%, and the titer was greater than four times in 97% (32/33) of patients. The titer of IgG antibody in the herpes group was significantly lower than that in the non-herpes group, and the difference between the two groups was statistically significant (P = 0.017). The serum HSV-1-IgG in most of the PTN patients was positive. Latent HSV-1 in the trigeminal ganglion may be reactivate after PTN surgery to produce ipsilateral oral and facial herpes infection. The infection of HSV-1 reactivation after PTN surgery was positively correlated with the operation time but negatively correlated with the titer of HSV-1-IgG antibody before PTN surgery. The incidence of HSV-1 infection after PTN operation is related to different surgical procedures.

Diagnostic efficacy of FibroScan for liver inflammation in patients with chronic hepatitis B: a single-center study with 1185 liver biopsies as controls

Background

Noninvasive diagnostic technologies that can dynamically monitor changes in liver inflammation are highly important for the management of chronic hepatitis B (CHB) patients and thus warrant further exploration. This study assessed the diagnostic efficacy of FibroScan for liver inflammation in CHB patients.

Methods

A total of 1185 patients were selected, and ultrasound-guided liver biopsy was performed within 1 month after the FibroScan test. The liver stiffness measurement (LSM), the reliability criteria (IQR/M) of LSM, the quality of liver biopsy (complete portal area, PA), and the liver inflammation grades were the main observation items of this study. With liver biopsy as the control, the diagnostic efficacy of FibroScan for liver inflammation in CHB patients was evaluated by receiver operating characteristic (ROC) curve analysis.

Results

The grade of liver inflammation was positively correlated with the stage of fibrosis (rho = 0.829, P < 0.001). Different grades of inflammation will have significant rise in LSM values within the same fibrosis stage, and LSM values were positively correlated with liver inflammation grade and fibrosis stage, and the rho is 0.579 and 0.593 respectively (P < 0.001). Significant differences in the LSM of FibroScan were observed among different grades of liver inflammation (P < 0.0001). Liver biopsy (PA > 10) served as the control, and the cutoff point and the area under ROC curves (AUCs) of the LSMs for different inflammation grades were as follows: G2, 8.6 kPa, 0.775; G3 9.8 kPa, 0.818; and G4, 11.0 kPa; 0.832. With LSM cutoff values of 8.6 kPa, 9.8 kPa and 11.0 kPa, FibroScan showed certain diagnostic value for CHB patients with G2, G3 and G4 liver inflammation, especially those with G4 inflammation.

Conclusions

The grade of liver inflammation was positively correlated with the stage of fibrosis, different grades of inflammation will have significant rise in LSM values within the same fibrosis stage. In addition to liver fibrosis, FibroScan could evaluate liver inflammation in CHB patients in a noninvasive manner.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02108-0.

Control and Prevention of the COVID-19 Epidemic in China: A Qualitative Community Case Study

Background

Cross-infection among residents in communities is one of the most critical reasons for the rapid spread of the COVID-19 epidemic. The COVID-19 epidemic has been well controlled within Chinese communities, which has made important contributions to the country's fight against it.

Methods

In this study, a qualitative case study design, with mixed methods applied to data collection and analysis, was employed to explore epidemic prevention measures taken by a Chinese community, namely Mulin, during the pandemic.

Results

The Mulin community established an integrated plan for epidemic prevention, including the prevention of the invasion of COVID-19, the prevention of cross-infection within the community, gaining the residents' trust and support, and providing the residents with convenient services.

Conclusion

In the present work, the Mulin community was taken as a typical case study, and qualitative methods were employed to comprehensively summarize the practice and experience of the community's epidemic prevention. Mulin's practices could shed light on how communities in other countries, especially developing countries with large populations, can prevent the spread of COVID-19.

MiR-4282 is a tumor-suppressor gene for preventing metastasis of epithelial ovarian cancer by negatively regulating MIER1

OBJECTIVE

To elucidate the biological role of miR-4282 in influencing metastasis of epithelial ovarian cancer (EOC) by regulating MIER1.

PATIENTS AND METHODS

MiR-4282 expressions in 45 cases of EOC specimens and normal controls were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The relationship between miR-4282 and clinical features in EOC patients, including pathological indicators and overall survival, was analyzed. After intervening miR-4282 level in SKOV3 and 3AO cells by plasmid transfection, changes in migratory and invasive abilities were determined by transwell assay and wound healing assay. The target gene of miR-4282 was observed by Dual-Luciferase reporter assay, followed by exploration of its involvement in EOC progression via rescue experiments.

RESULTS

MiR-4282 was downregulated in EOC specimens than normal controls. EOC patients expressing low level of miR-4282 had higher incidences of lymphatic metastasis and distant metastasis, as well as worse prognosis than those overexpressing miR-4282. Overexpression of miR-4282 in SKOV3 cells weakened metastatic ability, and conversely, knockdown of miR-4282 in 3AO cells yielded the promotive trends. MIER1 was confirmed to be the target gene binding miR-4282, which was highly expressed in EOC specimens. MIER1 was able to reverse the regulatory effect of miR-4282 on EOC cell metastasis.

CONCLUSIONS

Lowly expressed miR-4282 in EOC specimens is closely linked to the incidence of metastasis and overall survival. MiR-4282 prevents EOC metastasis by a negative regulation on MIER1.

Transcription factor OsbZIP49 controls tiller angle and plant architecture through the induction of indole-3-acetic acid-amido synthetases in rice

Tiller angle is an important determinant of plant architecture in rice (Oryza sativa L.). Auxins play a critical role in determining plant architecture; however, the underlying metabolic and signaling mechanisms are still largely unknown. In this study, we have identified a member of the bZIP family of TGA class transcription factors, OsbZIP49, that participates in the regulation of plant architecture and is specifically expressed in gravity-sensing tissues, including the shoot base, nodes and lamina joints. Transgenic rice plants overexpressing OsbZIP49 displayed a tiller-spreading phenotype with reduced plant height and internode lengths. In contrast, CRISPR/Cas9-mediated knockout of OsbZIP49 resulted in a compact architecture. Follow-up studies indicated that the effects of OsbZIP49 on tiller angles are mediated through changes in shoot gravitropic responses. Additionally, we provide evidence that OsbZIP49 activates the expression of indole-3-acetic acid-amido synthetases OsGH3-2 and OsGH3-13 by directly binding to TGACG motifs located within the promoters of both genes. Increased GH3-catalyzed conjugation of indole-3-acetic acid (IAA) in rice transformants overexpressing OsbZIP49 resulted in the increased accumulation of IAA-Asp and IAA-Glu, and a reduction in local free auxin, tryptamine and IAA-Glc levels. Exogenous IAA or naphthylacetic acid (NAA) partially restored shoot gravitropic responses in OsbZIP49-overexpressing plants. Knockout of OsbZIP49 led to reduced expression of both OsGH3-2 and OsGH3-13 within the shoot base, and increased accumulation of IAA and increased OsIAA20 expression levels were observed in transformants following gravistimulation. Taken together, the present results reveal the role transcription factor OsbZIP49 plays in determining plant architecture, primarily due to its influence on local auxin homeostasis.

Characterization of Cowhage-induced Pruritus in Sensitive Skin: An Observational Laboratory Study

Sensitive skin is a prevalent syndrome, characterized by discomfort in response to mild stimuli, which impacts on quality of life. Pruritus is one of the major symptoms of sensitive skin. However, the pathomechanism of sensitive skin is insufficiently understood. As an experimental model for pruritus, the cowhage skin prick test might provide insight into the understanding of sensitive skin. This study aimed to specify the characteristics of cowhage-induced pruritus in sensitive skin. Female volunteers, 20 with sensitive skin and 20 controls, were recruited. Self-report questionnaires were distributed and the responses evaluated; moreover, alongside assessments by dermatologists, skin physiology assessments, lactic acid sting test, capsaicin test and cowhage skin challenge were performed. Pruritus in sensitive skin was perceived as more intense and longer-lasting than in normal skin, with different qualities of accompanying sensations. Cowhage skin challenge results showed moderate consistency with clinical assessments. The results suggest that cowhage skin challenge could be a new tool for the assessment of sensitive skin.

CypB promotes cell proliferation and metastasis in endometrial carcinoma

Background

The molecular pathogenesis of endometrial cancer is not completely understood. CypB upregulated in many cancers, however, its role in endometrial carcinoma has not been studied. Here, we determine the effect of CypB on the growth of endometrial cancer.

Methods

In this study, we examined the expression of CypB in endometrial cancer tissues using immunohistochemistry. CypB silenced in HEC-1-B cell line by shRNA. CCK-8, colony formation assays, wound healing assays, and transwell analysis were performed to assess its effect on tumor cell proliferation and metastasis. Furthermore, microarray analysis was carried out to compare the global mRNA expression profile between the HEC-1-B and CypB-silenced HEC-1-B cells. Gene ontology and KEGG pathway enrichment analysis were performed to determine the potential function of differentially expressed genes related to CypB.

Results

We found that CypB was upregulated in endometrial cancer, inhibit CypB expression could significantly suppress cell proliferation, metastasis, and migration. We identified 1536 differentially expressed genes related to CypB (onefold change, p < 0.05), among which 652 genes were upregulated and 884 genes were downregulated. The genes with significant difference in top were mainly enriched in the cell cycle, glycosphingolipid biosynthesis, adherens junctions, and metabolism pathways.

Conclusion

The results of our study suggest that CypB may serve as a novel regulator of endometrial cell proliferation and metastasis, thus representing a novel target for gene-targeted endometrial therapy.

Trial registration

YLYLLS [2018] 008. Registered 27 November 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08374-7.

Meta-analysis of competitive antagonists in asthma treatment

BACKGROUND

This meta-analysis was developed to explore the efficacy of using antagonists to the chemokine receptor of T helper type 2 (Th2) cells (CRTH2) in the treatment of asthma, so as to provide theoretical foundation and assistance for treatment of asthma.

METHODS

The Boolean logic search method (Boolean method) was adopted to search the publications in PubMed, Medline, and HowNet with "antagonist", "asthma", "competitive antagonist", and "efficiency" as the search terms. The publications taking placebo as control to treat the asthma were searched. The Review Manager software was applied for meta-analysis.

RESULTS

A total of 13 publications were included in this study, and most of them were low-risk bias (medium-high quality). The results of Meta-analysis showed that the treatment methods of the two groups of patients showed no statistically heterogeneous effects on the one-second forced expiratory volume (FEV1) in the maximum exhalation after the maximum deep inhalation (Chi2 =4.70, I2=0%, and P=0.79). The FEV1 of the control group was much lower than that of the experimental group (Z=3.61, P=0.0003). There was no great difference in the incidence of adverse events between the two groups (Z=0.46, P=0.64). No statistical heterogeneity (Chi2 =3.72, I2=0%, P=0.45) and difference (Z=1.57, P=0.12) were found in asthma exacerbation between the two groups. The asthma control questionnaire (ACQ) score of the control group was much lower than that of the experimental group (Z=3.20, P=0.001).

CONCLUSIONS

Competitive antagonists of CRTH2 could effectively improve FEV1 and lower ACQ scores in patients with asthma, and were therefore effective in treating asthma.

The correlation between selenium levels and autoimmune thyroid disease: a systematic review and meta-analysis

BACKGROUND

This investigation systematically evaluated the selenium levels and the effects of selenium supplementation in patients with autoimmune thyroid disease (AITD).

METHODS

Randomized controlled trials (RCTs) related to selenium supplementation in patients with AITD were selected from the PubMed, Medline, Web of Sciences, Embase, Cochrane Library, and Spring databases. All related literature published between January 2000 and November 2020 were included. The RCT bias risk assessment was conducted according to the Cochrane Handbook 5.0.2. The Review Manager 5.3 software was applied for meta-analysis of the included literature.

RESULTS

A total of 17 articles meeting the requirements were selected, including a total of 1,911 subjects. Meta-analysis results showed that the serum free triiodothyronine (FT3) levels in patients was greatly reduced after selenium supplementation compared to placebo treatment (MD =-0.40; 95% confidential interval (CI): -0.70--0.10; Z=2.61; P=0.009). Serum free thyroxine (FT4) levels and anti-thyroid peroxidase antibody (TPOAb) levels were also significantly reduced (MD = -0.76; 95% CI: -1.58--0.07; Z=1.79; P=0.07), and anti-thyroid peroxidase antibody (TPOAb) level was decreased observably (MD =-150.25; 95% CI: -04.06--96.43; Z=5.47; P<0.00001). The thyroid stimulating hormone (TSH) levels (MD =0.06; 95% CI: -0.53-0.66; Z=0.21; P=0.83) and anti-thyroglobulin antibody (TGAb) levels (MD =17.19; 95% CI: -254.86-289.25; Z=0.12; P=0.90) were not significantly different between the experimental group and the control group.

CONCLUSIONS

Selenium-containing drugs were effective in treating AITD patients, and greatly reduced the levels of FT3, FT4, and TPOAb in AITD patients. These results suggested that selenium level had a great effect on AITD and selenium supplementation showed a very important effect on AITD.

Beta-blocker and survival in patients with lung cancer: A meta-analysis

Background

Beta-blocker (BB) is suggested to have anticancer efficacy. However, the potential influence of BB use on overall survival (OS) in patients with lung cancer remains undetermined. We aimed to evaluate the above relationship in an updated meta-analysis.

Methods

Observational studies comparing OS between users and non-users of BB with lung cancer were identified by search of PubMed, Embase, and Cochrane’s Library. A random-effect model was used to pool the results.

Results

Ten retrospective cohort studies with 30870 patients were included. Overall, BB use was not associated with significantly improved OS in lung cancer (hazard ratio [HR] = 1.02, 95% confidence interval [CI]: 0.98 to 1.06, p = 0.33) with moderate heterogeneity (I² = 29%). Stratified analyses showed similar results in patients with non-small cell lung cancer and small cell lung cancer, in studies with BB use before and after the diagnosis of lung cancer, and in studies with or without adjustment of smoking. Use of BB was associated with improved OS in patients with stage III lung cancer (HR = 0.91, 95% CI: 0.85 to 0.98, p = 0.02) and in patients that did not receive surgery resection (HR = 0.78, 95% CI: 0.64 to 0.96, p = 0.02), while use of non-selective BB was associated with worse OS (HR = 1.14, 95% CI: 1.01 to 1.28, p = 0.03).

Conclusions

This meta-analysis of retrospective cohort studies does not support a significant association between BB use and improved OS in lung cancer.

[Effect of levothyroxine treatment on pregnancy outcomes in euthyroid women with thyroid autoantibody positive: a Meta-analysis]

Objective: To conduct a systematic review of the association of levothyroxine treatment with pregnancy outcomes in euthyroid women who are thyroid autoantibody positive. Methods: Medline, Excerpta Medica (EMBASE), Cochrane Library, China National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), Wanfang data and VIP database were searched from inception until Jan. 28, 2020. All published randomized controlled trials assessing the association of levothyroxine treatment with pregnancy outcomes in euthyroid women with thyroid autoantibody-positive were included. STATA 11.0 and RevMan 5.3 softwares were used to perform this Meta-analysis. Results: A total of 6 studies met the inclusion criteria, with 2 188 women randomized. Meta-analysis showed that there was no significantly association between miscarriage (OR=0.85, 95%CI: 0.65-1.11, P=0.234) and preterm birth (OR=0.79, 95%CI: 0.54-1.16, P=0.224) with levothyroxine treatment. Conclusions: Levothyroxine therapy could not reduce the risk of miscarriage and preterm birth in euthyroid women with thyroid autoantibody-positive. Therefore, levothyroxine should be used with caution for these pregnant women.

miR‑576‑3p overexpression enhances cisplatin sensitivity of ovarian cancer cells by dysregulating PD‑L1 and cyclin D1

Cisplatin (DDP) resistance is a major obstacle in the chemotherapeutic efficacy of ovarian cancer. The present study aimed to explore the role of miR‑576‑3p in DDP sensitivity of ovarian cancer cells. Ovarian cancer cell lines SKOV3 and A2780 and DDP‑resistant ovarian cancer cell lines SKOV3/DDP and A2780/DDP were used in the present study. In vitro studies demonstrated that microRNA (miR)‑576‑3p overexpression increased the DDP sensitivity of DDP‑resistant ovarian cancer cells. A dual‑luciferase assay verified that both programmed death‑ligand 1 (PD‑L1) and cyclin D1 were targets of miR‑276‑3p and were reversely associated with the expression of miR‑576‑3p. Moreover, in vivo studies indicated that tumorigenesis was inhibited by DDP, which was enhanced by further miR‑576‑3p overexpression in tumor tissues. Taken together, the results suggested that miR‑576‑3p overexpression increased DDP chemosensitivity of ovarian cancer cells via decreasing PD‑L1 and cyclin D1, indicating that miR‑576‑3p may serve as a promising therapeutic target for ovarian cancer.

Genome-wide Analyses Identify a Novel Risk Locus for Nonsyndromic Cleft Palate

The 3 major subphenotypes observed in patients with nonsyndromic orofacial clefts (NSOFCs) are nonsyndromic cleft lip only (NSCLO), nonsyndromic cleft lip with palate (NSCLP), and nonsyndromic cleft palate only (NSCPO). However, the genetic architecture underlying NSCPO is largely unknown. Here we performed a 2-stage genome-wide association study (GWAS) on NSCPO and replication analyses of selected variants in other NSOFCs from the Chinese Han population. We identified a novel locus (15q24.3) and a known locus (1q32.2) where variants in or near the gene reached genome-wide significance (2.80 × 10^-13 < P < 1.72 × 10^-08) in a test for association with NSCPO in a case-control design. Although a variant from 15q24.3 was found to be significantly associated with both NSCPO and NSCLP, the direction of estimated effects on risk were opposite. Our functional annotation of the risk alleles within 15q24.3 coupled with previously established roles of the candidate genes within identified risk loci in periderm development, embryonic patterning, and/or regulation of cellular processes supports their involvement in palate development and the pathogenesis of cleft palate. Our study advances the understanding of the genetic basis of NSOFCs and provides novel insights into the pathogenesis of NSCPO.

Enhanced Oral Bioavailability of Felodipine from Solid Lipid Nanoparticles Prepared Through Effervescent Dispersion Technique

Felodipine (FLD), a dihydropyridine calcium channel blocker with excellent antihypertensive effect, is poorly soluble and undergoes extensive hepatic metabolism, which lead to poor oral bioavailability (about 15%) and limit its clinic application. The goal of this study was to develop solid lipid nanoparticles (SLNs) loading FLD to improve the oral bioavailability. The FLD loaded solid lipid nanoparticles (FLD-SLNs) were prepared by the effervescent dispersion technique developed by our laboratory, which might have some advantages over traditional methods. The FLD-SLNs showed desired particle characteristics with particle size (198.15 ± 1.82 nm), poly dispersity index (0.26 ± 0.02), zeta-potential (- 25.53 ± 0.60 mV), entrapment efficiency (95.65 ± 0.70%), drug loading (2.33 ± 0.10%), and a spherical appearance. Pharmacokinetic results showed that the FLD-SLNs presented 3.17-fold increase in area under the curve (AUC_(0-t)) compared with free FLD after oral administration in beagle dogs, which indicated that SLNs prepared using the effervescent dispersion technique can improve the bioavailability of lipophilic drugs like felodipine by enhancement of absorption and reduction first-pass metabolism.

Short-term skin reactions following use of N95 respirators and medical masks

Background

In the context of the COVID‐19 pandemic, cases of adverse skin reactions related to the wearing of masks have been observed.

Objectives

To analyze the short‐term effects of N95 respirators and medical masks, respectively, on skin physiological properties and to report adverse skin reactions caused by the protective equipment.

Methods

This study used a randomized crossover design with repeated measurements. Twenty healthy Chinese volunteers were recruited. Skin parameters were measured on areas covered by the respective masks and on uncovered skin 2 and 4 hours after donning, and 0.5 and 1 hour after removing the masks, including skin hydration, transepidermal water loss (TEWL), erythema, pH, and sebum secretion. Adverse reactions were clinically assessed, and perceived discomfort and non‐compliance measured.

Results

Skin hydration, TEWL, and pH increased significantly with wearing the protective equipment. Erythema values increased from baseline. Sebum secretion increased both on the covered and uncovered skin with equipment‐wearing. There was no significant difference in physiological values between the two types of equipment. More adverse reactions were reported following a N95 mask use than the use of a medical mask, with a higher score of discomfort and non‐compliance.

Conclusions

This study demonstrates that skin biophysical characters change as a result of wearing a mask or respirator. N95 respirators were associated with more skin reactions than medical masks.