Development and validation of a simple and practical model for early detection of diabetic macular edema in patients with type 2 diabetes mellitus using easily accessible systemic variables.

OBJECTIVE: Diabetic macular edema (DME) is the leading cause of visual impairment in patients with diabetes mellitus (DM). The goal of early detection has not yet achieved due to a lack of fast and convenient methods. Therefore, we aim to develop and validate a prediction model to identify DME in patients with type 2 diabetes mellitus (T2DM) using easily accessible systemic variables, which can be applied to an ophthalmologist-independent scenario. METHODS: In this four-center, observational study, a total of 1994 T2DM patients who underwent routine diabetic retinopathy screening were enrolled, and their information on ophthalmic and systemic conditions was collected. Forward stepwise multivariable logistic regression was performed to identify risk factors of DME. Machine learning and MLR (multivariable logistic regression) were both used to establish prediction models. The prediction models were trained with 1300 patients and prospectively validated with 104 patients from Guangdong Provincial People's Hospital (GDPH). A total of 175 patients from Zhujiang Hospital (ZJH), 115 patients from the First Affiliated Hospital of Kunming Medical University (FAHKMU), and 100 patients from People's Hospital of JiangMen (PHJM) were used as external validation sets. Area under the receiver operating characteristic curve (AUC), accuracy (ACC), sensitivity, and specificity were used to evaluate the performance in DME prediction. RESULTS: The risk of DME was significantly associated with duration of DM, diastolic blood pressure, hematocrit, glycosylated hemoglobin, and urine albumin-to-creatinine ratio stage. The MLR model using these five risk factors was selected as the final prediction model due to its better performance than the machine learning models using all variables. The AUC, ACC, sensitivity, and specificity were 0.80, 0.69, 0.80, and 0.67 in the internal validation, and 0.82, 0.54, 1.00, and 0.48 in prospective validation, respectively. In external validation, the AUC, ACC, sensitivity and specificity were 0.84, 0.68, 0.90 and 0.60 in ZJH, 0.89, 0.77, 1.00 and 0.72 in FAHKMU, and 0.80, 0.67, 0.75, and 0.65 in PHJM, respectively. CONCLUSION: The MLR model is a simple, rapid, and reliable tool for early detection of DME in individuals with T2DM without the needs of specialized ophthalmologic examinations.

Effect of repetitive transcranial magnetic stimulation-assisted training on lower limb motor function in children with hemiplegic cerebral palsy.

OBJECTIVE: To explore the effect of repetitive transcranial magnetic stimulation (rTMS)-assisted training on lower limb motor function in children with hemiplegic cerebral palsy (HCP). METHOD: Thirty-one children with HCP who met the inclusion criteria were selected and randomly divided into a control group (n = 16) and an experimental group (n = 15). The control group received routine rehabilitation treatment for 30 min each time, twice a day, 5 days a week for 4 weeks. Based on the control group, the experimental group received rTMS for 20 min each time, once a day, 5 days a week for 4 weeks. The outcome measures included a 10-metre walk test (10MWT), a 6-minute walk distance (6MWD) test, D- and E-zone gross motor function measurements (GMFM), the symmetry ratio of the step length and stance time and the muscle tone of the triceps surae and the hamstrings (evaluated according to the modified Ashworth scale), which were obtained in both groups of children before and after treatment. RESULTS: After training, the 10MWT (P < 0.05), 6MWD (P < 0.01), GMFM (P < 0.001) and the symmetry ratio of the step length and stance time of the two groups were significantly improved (P < 0.05), there was more of an improvement in the experimental group compared with the control group. There was no significant change in the muscle tone of the hamstrings between the two groups before and after treatment (P > 0.05). After treatment, the muscle tone of the triceps surae in the experimental group was significantly reduced (P < 0.05), but there was no significant change in the control group (P > 0.05). CONCLUSION: Repetitive TMS-assisted training can improve lower limb motor function in children with HCP.

Quality of Life Benefit and Clinical Predictors of Complete Skin Clearance in Psoriasis: A Multicenter, Prospective, Real-World Study.

BACKGROUND: Newer biologics, such as interleukin (IL)-17 inhibitors, make it possible to achieve complete skin clearance (CSC) in patients with moderate-to-severe psoriasis. However, the clinical meaningfulness and predictive factors of CSC in daily practice have not yet been fully investigated. OBJECTIVE: The study was conducted to, first, assess the impact of CSC on quality of life (QoL) improvements compared with treatment responses without clearance and, second, identify clinical parameters as predictors of CSC response in psoriasis patients treated with ixekizumab. METHODS: Patients attending 26 dermatology centers across China were recruited into this real-world setting between August 2020 and May 2022. Prospective cohort study in which response to ixekizumab was assessed using the Psoriasis Area and Severity Index (PASI) and Dermatology Quality of Life Index (DLQI). The absolute DLQI score and DLQI (0) response at week 12 were compared between groups achieving various levels of skin clearance. A stepwise logistic regression analysis was applied to identify which baseline clinical characteristics were predictive factors for CSC. RESULTS: After 12 weeks of treatment, 226 of 511 (44.2%) patients achieved CSC, defined as 100% improvement in PASI score (PASI-100). A significantly higher proportion of patients with CSC versus almost clear skin (PASI 90-99) achieved DLQI score of 0, corresponding to the experience of no impairment on QoL (54.4% vs. 37.7%, p = 0.001). Females patients were more likely than males to achieve CSC response (odds ratio [OR] = 1.83; 95% confidence interval [CI]: 1.24-2.70), while previous biologic treatment (OR = 0.43; 95% CI: 0.24-0.81) and joint affected (OR = 0.61; 95% CI: 0.42-0.89) were significantly associated with less CSC response. CONCLUSIONS: This study highlights the fact that clinical parameters are important in determining CSC response in psoriasis. In daily practice, achieving CSC represents a clinically meaningful treatment goal, especially from the patient perspective.

Association between sociodemographic status and cardiovascular risk factors burden in community populations: implication for reducing cardiovascular disease burden.

BACKGROUND: We aimed to evaluate the burden of cardiovascular (CV) risk factors in the community populations of Guangdong Province and its association with sociodemographic status (SDS). METHOD: The data were from the community populations of Guangdong Province who have participated in the China PEACE Million Persons Project between 2016 and 2020 (n = 102,358, women 60.5% and mean age 54.3 years). The prevalence of CV risk factors (smoking, drinking, overweight/obesity, hypertension, dyslipidemia and diabetes mellitus) and its association with SDS (age, sex and socioeconomic status [SES]) was evaluated cross-sectionally. RESULTS: The prevalence of overweight/obesity was 48.9%, hypertension 39.9%, dyslipidemia 18.6%, smoking 17.2%, diabetes mellitus 16.1% and drinking 5.3%. Even in young adults (aged 35-44), nearly 60% had at least 1 CV risk factor. Overweight/obesity often coexisted with other risk factors, including smoking, hypertension, dyslipidemia and diabetes mellitus. The proportion of people with no risk factor decreased with increasing age. Women were more likely than men to have no CV risk factor (29.4% vs. 12.7%). People with ≥ high school degree were more likely than those with < high school to have no risk factor (28.5% vs. 20.4%), and farmers were less likely than non-farmers to have no risk factor (20.8% vs. 23.1%). CONCLUSION: The burden of CV risk factors is high and varied by SDS in the community populations of Guangdong Province. Cost-effective and targeted interventions are needed to reduce the burden of CV risk factors at the population level.

Pulmonary fibrosis and its related factors in discharged patients with new corona virus pneumonia: a cohort study.

BACKGROUND: Thousands of Coronavirus Disease 2019 (COVID-19) patients have been discharged from hospitals Persistent follow-up studies are required to evaluate the prevalence of post-COVID-19 fibrosis. METHODS: This study involves 462 laboratory-confirmed patients with COVID-19 who were admitted to Shenzhen Third People's Hospital from January 11, 2020 to April 26, 2020. A total of 457 patients underwent thin-section chest CT scans during the hospitalization or after discharge to identify the pulmonary lesion. A total of 287 patients were followed up from 90 to 150 days after the onset of the disease, and lung function tests were conducted about three months after the onset. The risk factors affecting the persistence of pulmonary fibrosis were identified through regression analysis and the prediction model of the persistence of pulmonary fibrosis was established. RESULTS: Parenchymal bands, irregular interfaces, reticulation and traction bronchiectasis were the most common CT features in all COVID-19 patients. During the 0-30, 31-60, 61-90, 91-120 and > 120 days after onset, 86.87%, 74.40%, 79.56%, 68.12% and 62.03% patients developed with pulmonary fibrosis and 4.53%, 19.61%, 18.02%, 38.30% and 48.98% patients reversed pulmonary fibrosis, respectively. It was observed that Age, BMI, Fever, and Highest PCT were predictive factors for sustaining fibrosis even after 90 days from onset. A predictive model of the persistence with pulmonary fibrosis was developed based-on the Logistic Regression method with an accuracy, PPV, NPV, Sensitivity and Specificity of the model of 76%, 71%, 79%, 67%, and 82%, respectively. More than half of the COVID-19 patients revealed abnormal conditions in lung function after 90 days from onset, and the ratio of abnormal lung function did not differ on a statistically significant level between the fibrotic and non-fibrotic groups. CONCLUSIONS: Persistent pulmonary fibrosis was more likely to develop in patients with older age, higher BMI, severe/critical condition, fever, a longer viral clearance time, pre-existing disease and delayed hospitalization. Fibrosis developed in COVID-19 patients could be reversed in about a third of the patients after 120 days from onset. The pulmonary function of less than half of COVID-19 patients could turn to normal condition after three months from onset. An effective prediction model with an average area under the curve (AUC) of 0.84 was established to predict the persistence of pulmonary fibrosis in COVID-19 patients for early diagnosis.

Polymerase Chain Reaction Assays Reverted to Positive in 25 Discharged Patients With COVID-19.

We report the observation that 14.5% of COVID-19 patients had positive RT-PCR testing again after discharge. We describe correlations between laboratory parameters and treatment duration (P = .002) and time to virus recrudescence (P = .008), suggesting the need for additional measures to confirm illness resolution in COVID-19 patients.

The correlation between viral clearance and biochemical outcomes of 94 COVID-19 infected discharged patients.

OBJECTIVE: This study aims to evaluate the correlation between viral clearance and blood biochemical index of 94 discharged patients with COVID-19 infection in Shenzhen Third People's Hospital, enrolled from Jan 5 to Feb 13, 2020. METHODS: The clinical and laboratory findings were extracted from the electronic medical records of the patients. The data were analysed and reviewed by a trained team of physicians. Information on clinical signs and symptoms, medical treatment, virus clearance, and laboratory parameters including interleukin 6 (IL-6) and C-reactive protein were collected. RESULTS: COVID-19 mRNA clearance ratio was identified significantly correlated with the decline of serum creatine kinase (CK) and lactate dehydrogenase (LDH) levels. Furthermore, COVID-19 mRNA clearance time was positively correlated with the length of hospital stay in patients treated with either IFN-α + lopinavir/ritonavir or IFN-α + lopinavir/ritonavir + ribavirin. CONCLUSIONS: Therapeutic regimens of IFN-α + lopinavir/ritonavir and IFN-α + lopinavir/ritonavir + ribavirin might be beneficial for treatment of COVID-19. Serum LDH or CK decline may predict a favorable response to treatment of COVID-19 infection.

SHARPIN overexpression promotes TAK1 expression and activates JNKs and NF-κB pathway in Mycosis Fungoides.

Mycosis Fungoides (MF) is the most common subtype of cutaneous T-cell lymphomas (CTCL). Shank-associated RH domain-interacting protein (SHARPIN) participates in the initiation and development of multiple tumors. However, the clinical significance of SHARPIN in MF hasn't been investigated. The c-Jun N-terminal kinases (JNKs) pathway is a member of mitogen-activated protein kinases (MAPKs). Its dysregulation is observed in various tumors including CTCL, whereas the roles of JNKs pathway in MF remain largely unknown, the relationship between SHARPIN and JNKs pathway remains elusive. Herein, we showed that upregulated expression of SHARPIN was related to poor prognosis of MF patients. In vitro experiments found increased SHARPIN expression and activation of JNKs pathway in MF cell line MyLa2059. SHARPIN induced transforming growth factor ß activated kinase-1 (TAK1) transcription, which is an upstream kinase of JNKs, NF-κB and p38 pathway, leading to activation of JNKs and NF-κB pathway. SHARPIN also promoted p38 signalling independent of TAK1 expression, by which overexpression of SHARPIN induced cell proliferation, inhibited apoptosis, enhanced migration and invasion of MyLa2059. Our work provided direct evidences for effects of SHARPIN on JNKs and NF-κB pathway, and the contributing roles of JNKs, NF-κB and p38 pathway regulated by SHARPIN in the development of MF.

Adherence to Moisturizing Subjects in Patient with Dry Skin in the Winter.

Dry skin in winter and moisturization are important topics. We included 72 patients with a diagnosis of dry skin in winter, and the patients were instructed to apply moisturizing products as part of their treatment plan from October 2017 to January 2018. We contacted the patients via telephone 2 weeks after the dermatologist appointment. The results from this study showed that patient adherence to dermatologist-recommended moisturizers is low. This study indicates that patients need more guidance in their dry skin treatment.

Down-regulated SHARPIN may accelerate the development of atopic dermatitis through activating interleukin-33/ST2 signalling.

SHARPIN is an important component of the linear ubiquitin chain assembly complex (LUBAC). Loss of function of SHARPIN results in eosinophilic inflammation in multiple organs including skin with Th2 -dominant cytokines and dysregulated development of lymphoid tissues in mice. The clinicopathological features are similar to atopic dermatitis (AD) in humans. In order to investigate the potential role of SHARPIN in the pathogenesis of AD, we performed genetic association study of the genotypes and haplotypes as well as SHARPIN's expression between AD cases and controls. We found three mutations (g.480G>A, g.4576A>G and g.5070C>T) in patient group, and significantly decreased expression in AD lesions, suggesting a primary role of SHARPIN during AD development. Lentivirus-mediated in vitro assays identified that knockdown of SHARPIN can induce elevated expression of IL-33 and its orphan receptor ST2, FLG and STAT3 and NF-κB inactivation in HaCaT keratinocytes, which has been widely evidenced in regulating AD development. ST2 expression was highly induced in SHARPIN-silenced HaCaT keratinocytes after the combined stimulation of IL-4 and IL-13. Our in vivo and in vitro findings implicated that SHARPIN may be a novel participant in the pathogenesis and/or new therapeutic target of AD.

Azithromycin-resistant Neisseria gonorrhoeae isolates in Guangzhou, China (2009-2013): coevolution with decreased susceptibilities to ceftriaxone and genetic characteristics.

BACKGROUND: The recent emergence of azithromycin-resistant (AZM-R) N. gonorrhoeae isolates that have coevolved decreased susceptibility to extended-spectrum cephalosporins has caused great concern. Here we investigated the prevalence of decreased susceptibility to ceftriaxone (CRO(D)) in AZM-R isolates and genetically characterized AZM-R isolates in Guangzhou, China from 2009 to 2013. METHODS: The minimum inhibitory concentration (MIC) of AZM and ceftriaxone was determined using an agar-dilution method. All AZM-R isolates were screened for mutations in 23S rRNA, mtrR and penA genes and genotyped using N. gonorrhoeae multi-antigen sequence typing (NG-MAST). RESULTS: Of the 485 identified N. gonorrhoeae isolates, 445 (91.8%) were isolated from male urethritis subjects, and 77 (15.9%) were AZM-R (MIC ≥ 1 mg/L), including 33 (6.8%) with AZM low-level resistant (AZM-LLR, MIC = 1 mg/L) and 44 (9.1%) with AZM middle-level resistant (AZM-MLR, MIC ≥ 2 mg/L). Significantly more CRO(D) (MIC ≥ 0.125 mg/L) showed in AZM-MLR isolates (43.2%, 19/44) as compared with that in AZM-LLR isolates (18.2%, 6/33) (p < 0.05). For the 23S rRNA, mtrR, penA or combined 23S rRNA/MtrR/penA mutations, no significant difference was found between AZM-LLR isolates and AZM-MLR isolates (P > 0.05); similar results were detected between combined AZM-LLR/CRO(D) isolates and combined AZM-MLR/CRO(D) isolates (P > 0.05). No mutation A2059G or AZM high-level resistant (AZM-HLR, MIC ≥ 256 mg/L) isolate was detected. Among 77 AZM-R isolates, 67 sequence types (STs) were identified by NG-MAST, of which 30 were novel. Most STs were represented by a single isolate. CONCLUSIONS: The AZM-R together CRO(D) isolates are now present in Guangzhou, China, which deserve continuous surveillance and the mechanism of concurrent resistance needs further study.

[Novel missense mutations of the FLG gene identified in two Chinese families affected with ichthyosis vulgaris].

OBJECTIVE: To identify potential mutations of the FLG gene in two Chinese families affected with ichthyosis vulgaris. METHODS: All coding exons and exon-intron boundary of the FLG gene were amplified by polymerase chain reaction (PCR) and analyzed by direct sequencing. The results were compared with those of 100 unrelated healthy controls. RESULTS: Two novel missense mutations, c.1360A>G (p.T454A) and c.10363G>T (p.D3455Y), were detected in all affected individuals from family 1 and family 2 respectively but none of the controls. CONCLUSION: The c.1360A>G (p.T454A) and c.10363G>T (p.D3455Y) of the FLG gene may lead to alteration of the structure and function of the FLG protein and cause ichthyosis vulgaris in the two families.

Trends in antimicrobial resistance in Neisseria gonorrhoeae isolated from Guangzhou, China, 2000 to 2005 and 2008 to 2013.

A total of 1224 Neisseria gonorrhoeae isolates from Guangzhou in 2 periods (2000-2005 and 2008-2013) were subjected to antimicrobial susceptibility testing. The percentage of penicillin- and ciprofloxacin-resistant isolates increased from 71.1% (473/665) to 90.9% (508/559) and 88.9% (591/665) to 98.0% (548/559), respectively. All isolates remain susceptible to spectinomycin and ceftriaxone, with increasing minimum inhibitory concentrations.

The Safety of Ixekizumab in Chinese Adults with Moderate-to-Severe Plaque Psoriasis: Analyses from a Prospective, Single-Arm, Multicenter, 12-Week Observational Study.

INTRODUCTION: Ixekizumab, a monoclonal antibody against interleukin-17A, is efficacious and well tolerated for the treatment of moderate-to-severe plaque psoriasis. However, there are limited data on the real-world safety of ixekizumab in Chinese patient populations. We performed an observational study of ixekizumab for the treatment of moderate-to-severe plaque psoriasis in routine clinical practice in China. Here we present a further safety analysis of this study. METHODS: In this prospective, observational, single-arm, multicenter, post-marketing safety study, adults (≥18 years) with moderate-to-severe plaque psoriasis receiving ixekizumab were enroled at dermatology departments in hospitals across China and prospectively followed for 12 weeks or until their last dose of ixekizumab. In this analysis, we evaluated adverse events (AEs) of special interest (AESIs) identified using MedDRA® search strategies. We also analyzed AEs and AESIs occurring in greater than ten patients in subgroups by age (< 65/≥ 65 years), sex, body weight (< 60/60 kg to < 80/≥ 80 kg), renal impairment, hepatic impairment, history of tuberculosis, history of HBV infection, recent or active infection, history of allergic reaction/hypersensitivity, and number (0-1/2-4/5-7) of ixekizumab 80 mg injections after baseline until day 105. RESULTS: This analysis included 663/666 patients enrolled in the primary study. At least one AESI was reported in 224 (33.8%) patients and considered related to ixekizumab in 181 (27.3%); the most common were injection site reactions (n = 131, 19.8%), infections (n = 80, 12.1%), and allergic reactions/hypersensitivity events (n = 59, 8.9%). The proportion of patients with ≥ 1 AE was higher for females versus males (99/186, 53.2% versus 184/477, 38.6%, p = 0.0006). The proportion of patients with ≥ 1 AE increased with the number of ixekizumab injections after baseline [61/188 (32.4%) for zero to one injection, 151/338 (44.7%) for two to four injections, and 61/106 (57.5%) for five to seven injections; p = 0.0001]. CONCLUSIONS: In this real-world study, ixekizumab was well tolerated in Chinese patients with moderate-to-severe plaque psoriasis, with no difference in safety across most patient subgroups.

Effectiveness of Ixekizumab in Chinese Patients with Moderate-Severe Plaque Psoriasis with Special Area Involvement: Subanalysis of a Prospective, Multicenter, Observational Real-World Study.

INTRODUCTION: Ixekizumab, a monoclonal antibody against interleukin-17A, demonstrated effectiveness in the treatment of psoriasis in a Chinese real-world study that was consistent with previous randomized controlled trials. Here, we report further analyses from this study to explore the effectiveness of ixekizumab for treating patients with psoriasis and the involvement of special body areas (scalp, nail, joint, palmoplantar, or genital areas). METHODS: A multicenter, prospective, observational, single-arm, post-marketing surveillance study was conducted in patients aged ≥ 18 years with moderate-to-severe plaque psoriasis and prescribed with ixekizumab in 26 Chinese hospitals. Psoriasis Area and Severity Index (PASI) and Dermatology Life Quality Index (DLQI) scores were compared between patients with versus without psoriasis in special body areas in the overall study population and across subgroups by body area. RESULTS: In total, 612 patients were included. At baseline, most patients (93.6%) had psoriasis involvement in at least one special body area. Overall, patients with psoriasis in special body areas reported a worse quality of life (QoL) than those without. Patients with versus without psoriasis in special body areas achieved a comparable mean reduction from baseline in PASI score (10.9 vs. 9.2 at week 2, and 16.9 vs. 14.7 at week 12, respectively) and DLQI score (6.0 vs. 4.4 at week 2, and 9.9 vs. 7.5 at week 12, respectively); a similar proportion of patients also achieved PASI 50 at week 2, and PASI 75 and PASI 90 at week 12, and a DLQI (0/1) at weeks 2 and 12. Several significantly different results were reported between subgroups, the majority of which favored patients with special body area involvement. CONCLUSION: Most patients had psoriasis involvement in a special body area which was associated with worse QoL. Ixekizumab is similarly effective in reducing disease severity and improving QoL in patients with plaque psoriasis across different special body areas.

Genetic variation of promoter sequence modulates XBP1 expression and genetic risk for vitiligo.

Our previous genome-wide linkage analysis identified a susceptibility locus for generalized vitiligo on 22q12. To search for susceptibility genes within the locus, we investigated a biological candidate gene, X-box binding protein 1(XBP1). First, we sequenced all the exons, exon-intron boundaries as well as some 5' and 3' flanking sequences of XBP1 in 319 cases and 294 controls of Chinese Hans. Of the 8 common variants identified, the significant association was observed at rs2269577 (p_(trend) = 0.007, OR = 1.36, 95% CI = 1.09-1.71), a putative regulatory polymorphism within the promoter region of XBP1. We then sequenced the variant in an additional 365 cases and 404 controls and found supporting evidence for the association (p_(trend) = 0.008, OR = 1.31, 95% CI = 1.07-1.59). To further validate the association, we genotyped the variant in another independent sample of 1,402 cases and 1,288 controls, including 94 parent-child trios, and confirmed the association by both case-control analysis (p_(trend) = 0.003, OR = 1.18, 95% CI = 1.06-1.32) and the family-based transmission disequilibrium test (TDT, p = 0.005, OR = 1.93, 95% CI = 1.21-3.07). The analysis of the combined 2,086 cases and 1,986 controls provided highly significant evidence for the association (p_(trend) = 2.94x10(-6), OR = 1.23, 95% CI = 1.13-1.35). Furthermore, we also found suggestive epistatic effect between rs2269577 and HLA-DRB1*07 allele on the development of vitiligo (p = 0.033). Our subsequent functional study showed that the risk-associated C allele of rs2269577 had a stronger promoter activity than the non-risk G allele, and there was an elevated expression of XBP1 in the lesional skins of patients carrying the risk-associated C allele. Therefore, our study has demonstrated that the transcriptional modulation of XBP1 expression by a germ-line regulatory polymorphism has an impact on the development of vitiligo.

Longitudinal analysis of antibody dynamics in COVID-19 convalescents reveals neutralizing responses up to 16 months after infection.

Elucidating the dynamics of the neutralizing antibody (nAb) response in coronavirus disease 2019 (COVID-19) convalescents is crucial in controlling the pandemic and informing vaccination strategies. Here we measured nAb titres across 411 sequential plasma samples collected during 1-480 d after illness onset or laboratory confirmation (d.a.o.) from 214 COVID-19 convalescents, covering the clinical spectrum of disease and without additional exposure history after recovery or vaccination against SARS-CoV-2, using authentic SARS-CoV-2 microneutralization (MN) assays. Forty-eight samples were also tested for neutralizing activities against the circulating variants using pseudotyped neutralization assay. Results showed that anti-RBD IgG and MN titres peaked at ~120 d.a.o. and subsequently declined, with significantly reduced nAb responses found in 91.67% of COVID-19 convalescents (≥50% decrease in current MN titres compared with the paired peak MN titres). Despite this decline, majority of the COVID-19 convalescents maintained detectable anti-RBD IgG and MN titres at 400-480 d.a.o., with undetectable neutralizing activity found in 14.41% (16/111) of the mild and 50% (5/10) of the asymptomatic infections at 330-480 d.a.o. Persistent antibody-dependent immunity could provide protection against circulating variants after one year, despite significantly decreased neutralizing activities against Beta, Delta and Mu variants. In conclusion, these data show that despite a marked decline in neutralizing activity over time, nAb responses persist for up to 480 d in most convalescents of symptomatic COVID-19, whereas a high rate of undetectable nAb responses was found in convalescents from asymptomatic infections.

Comparisons of mouse models for hair follicle reconstitution.

Three methods are currently available to reconstitute hair follicles in mice. Direct comparisons have yet to be made to determine which method is most efficient. In this study, mouse epithelial cells (MECs) and mouse dermal cells (MDCs) were grafted onto the dorsal skin of nude mice using the chamber, flap or patch assays. Comparisons were made based on gross, scanning electron microscopic and histological observations. MDCs alone induced hair follicle reconstitution with the production of hairs yielding false-positive results caused by contamination by hair follicle remnants. Neither primary MECs nor cultured MDCs alone formed hair follicles but did result in hair follicle formation when mixed together. Frozen MECs or MDCs resulted in decreased hair follicle-inductive activity but could still regenerate hairs. The hair patch assay was the quickest model (20±3 days) to determine whether cell mixtures would reconstitute hair follicles that produce hairs; however, the hair follicles were randomly orientated and often associated with foreign body granulomas. The flap assay took the longest time (29±2 days) to produce follicles and hairs to develop with a clinically natural appearance, but an epidermal sheet was needed. The chamber assay was the most labour-intensive and cell number-dependent procedure but follicles developed in a dense, clinically normal manner.

Fine mapping of the psoriasis susceptibility locus PSORS1 supports HLA-C as the susceptibility gene in the Han Chinese population.

PSORS1 (psoriasis susceptibility gene 1) is a major susceptibility locus for psoriasis. Several fine-mapping studies have highlighted a 300-kb candidate region of PSORS1 where multiple biologically plausible candidate genes were suggested. The most recent study has indicated HLA-Cw6 as the primary PSORS1 risk allele within the candidate region in a Caucasian population. In this study, a family-based association analysis of the PSORS1 locus was performed by analyzing 10 polymorphic microsatellite markers from the PSORS1 region as well as HLA-B, HLA-C and CDSN loci in 163 Chinese families of psoriasis. Five marker loci show strong evidence (P<10(-3)), and one marker locus shows weak evidence (P = 0.04) for association. The haplotype cluster analysis showed that all the risk haplotypes are Cw6 positive and share a 369-kb region of homologous marker alleles which carries all the risk alleles, including HLA-Cw6 and CDSN*TTC, identified in this study. The recombinant haplotype analysis of the HLA-Cw6 and CDSN*TTC alleles in 228 Chinese families showed that the HLA-Cw6(-)/CDSN*TTC(+) recombinant haplotype is clearly not associated with risk for psoriasis (TratioNT = 29:57, p = 0.0025) in a Chinese population, suggesting that the CDSN*TTC allele itself does not confer risk without the presence of the HLA-Cw6 allele. The further exclusion analysis of the non-risk HLA-Cw6(-)/CDSN*TTC(+) recombinant haplotypes with common recombination breakpoints has allowed us to refine the location of PSORS1 to a small candidate region. Finally, we performed a conditional linkage analysis and showed that the HLA-Cw6 is a major risk allele but does not explain the full linkage evidence of the PSORS1 locus in a Chinese population. By performing a series of family-based association analyses of haplotypes as well as an exclusion analysis of recombinant haplotypes, we were able to refine the PSORS1 gene to a small critical region where HLA-C is a strong candidate to be the PSORS1 susceptibility gene.