Prevalence and genetic diversity of human rhinovirus among patients with acute respiratory infections in China, 2012-2021.

To understand the prevalence of rhinovirus (RV) among acute respiratory infection (ARI) patients, 10-year ARI surveillance in multiple provinces of China were conducted during 2012-2021. Of 15 645 ARI patients, 1180 (7.54%) were confirmed to have RV infection and 820 (69.49%) were children under 5 years of age. RV typing was performed on the 527 VP1 gene sequences, and species A, B, and C accounted for 73.24%, 4.93%, and 21.82%, respectively. Although no significant difference in the proportions of age groups or disease severity was found between RV species, RV-C was more frequently detected in children under 5 years of age, RV-A was more frequently detected in elderly individuals (≥60), and the proportions of pneumonia in RV-A and RV-C patients were higher than those in RV-B patients. The epidemic peak of RV-A was earlier than that of RV-C. A total of 57 types of RV-A, 13 types of RV-B, and 35 types of RV-C were identified in RV-infected patients, and two uncertain RV types were also detected. The findings showed a few differences in epidemiological and clinical features between RV species in ARI patients, and RV-A and RV-C were more prevalent than RV-B.

Genetic characterization of pediatric SARI-associated human adenoviruses in eight Chinese provinces during 2017-2021.

Human adenovirus (HAdV) is a significant viral pathogen causing severe acute respiratory infections (SARIs) in children. To improve the understanding of type distribution and viral genetic characterization of HAdV in severe cases, this study enrolled 3404 pediatric SARI cases from eight provinces of China spanning 2017-2021, resulting in the acquisition of 112 HAdV strains. HAdV-type identification, based on three target genes (penton base, hexon, and fiber), confirmed the diversity of HAdV types in SARI cases. Twelve types were identified, including species B (HAdV-3, 7, 55), species C (HAdV-1, 2, 6, 89, 108, P89H5F5, Px1/Ps3H1F1, Px1/Ps3H5F5), and E (HAdV-4). Among these, HAdV-3 exhibited the highest detection rate (44.6%), followed by HAdV-7 (19.6%), HAdV-1 (12.5%), and HAdV-108 (9.8%). All HAdV-3, 7, 55, 4 in this study belonged to dominant lineages circulating worldwide, and the sequences of the three genes demonstrated significant conservation and stability. Concerning HAdV-C, excluding the novel type Px1/Ps3H1F1 found in this study, the other seven types were detected both in China and abroad, with HAdV-1 and HAdV-108 considered the two main types of HAdV-C prevalent in China. Two recombinant strains, including P89H5F5 and Px1/Ps3H1F1, could cause SARI as a single pathogen, warranting close monitoring and investigation for potential public health implications. In conclusion, 5 years of SARI surveillance in China provided crucial insights into HAdV-associated respiratory infections among hospitalized pediatric patients.

Transmission Pattern of Measles Virus Circulating in China During 1993-2021: Genotyping Evidence Supports That China Is Approaching Measles Elimination.

BACKGROUND: To provide useful insights into measles elimination progress in China, measles surveillance data were reviewed, and the transmission patterns of measles viruses circulating in China during 1993-2021 were analyzed. METHODS: Measles incidence data from the National Notifiable Disease Reporting System of the China Center for Disease Control and Prevention were analyzed. A total of 17 570 strains were obtained from 30 of 31 provinces in mainland China during 1993-2021. The recommended genotyping window was amplified. Genotyping analysis was conducted for comparison with the reference strains. Phylogenetic analyses were performed to identify genetic relationships among different lineages within the genotypes. RESULTS: With high coverage of routine immunization and intensive supplementary immunization activities, measles incidence has shown a downward trend since 1993, despite 2 resurgences, reaching a historic low level in 2020-2021 (average 0.5 per million). During 1993-2021, 9 genotypes including domestic genotype H1; imported genotypes B3, D4, D8, D9, D11, G3, and H2; and vaccine-associated genotype A were identified. Among them, the genotype H1 strain circulated endemically in China for more than 25 years; the last strain was detected in Yunnan Province in September 2019. Multiple imported genotypes have been identified since 2009 showing different transmission patterns. Since April 2020, no imported strains have been detected, while vaccine-associated genotype A continues to be detected. CONCLUSIONS: The evidence of low incidence during 2020-2021 and virological surveillance data in this study confirm that China is currently approaching measles elimination.

Circulation pattern and genetic variation of human respiratory syncytial virus in China during 2008-2021.

To better understand the circulation pattern and genetic characterization of human respiratory syncytial virus (HRSV) in China during 2008-2021, a total of 3967 HVR2 sequences were obtained from 20 provinces in China for phylogenetic analysis and sequence variation analysis. The results showed that the HRSV subtype presented the prevalence pattern of "ABBAABAABAAABB." Further genotyping identified seven genotypes for HRSVA and nine genotypes for HRSVB. Multiple genotypes of HRSV were cocirculating during 2008-2015, while ON1 and BA9 became the only predominant genotypes for HRSVA and HRSVB, respectively, since 2015. A genotype switch from NA1 to ON1 for HRSVA occurred in approximately 2014, while genotype BA9 of HRSVB had been the predominant genotype for at least 14 years. ON1 strains could be divided into four lineages with no temporal or geographical distribution tendency. In contrast, BA9 strains could be divided into three lineages with noticeable temporal clustering. Sequence variation analysis showed that two ON1 sequences in 2017 had 10 nucleotide deletion and compensatory extension at the C-terminal; 15 BA9 sequences during 2019-2021 had novel insertions between K225 and E226, along with 6 identical amino acid variant sites. This study further enriched the genetic data of HRSV circulating in China and provided an important basis for the development of HRSV vaccines and drugs as well as the formulation of prevention and control strategies.

Molecular evolution and genomic characteristics of genotype H1 of measles virus.

Measles is one of the most infectious diseases of humans. It is caused by the measles virus (MeV) and can lead to serious illness, lifelong complications, and even death. Whole-genome sequencing (WGS) is now available to study molecular epidemiology and identify MeV transmission pathways. In the present study, WGS of 23 MeV strains of genotype H1, collected in Mainland China between 2006 and 2018, were generated and compared to 31 WGSs from the public domain to analyze genomic characteristics, evolutionary rates and date of emergence of H1 genotype. The noncoding region between M and F protein genes (M/F NCR) was the most variable region throughout the genome. Although the nucleotide substitution rate of H1 WGS was around 0.75 × 10-3 substitution per site per year, the M/F NCR had an evolutionary rate three times higher, with 2.44 × 10-3 substitution per site per year. Phylogenetic analysis identified three distinct genetic groups. The Time of the Most Recent Common Ancestor (TMRCA) of H1 genotype was estimated at approximately 1988, while the first genetic group appeared around 1995 followed by two other genetic groups in 1999-2002. Bayesian skyline plot showed that the genetic diversity of the H1 genotype remained stable even though the number of MeV cases decreased 50 times between 2014 (52 628) and 2020 (993). The current coronavirus disease 2019 (COVID-19) pandemic might have some effect on the measles epidemic and further studies will be necessary to assess the genetic diversity of the H1 genotype in a post-COVID area.

Comparative analysis of the clinical and epidemiological characteristics of human influenza virus versus human respiratory syncytial virus versus human metapneumovirus infection in nine provinces of China during 2009-2021.

A comparative analysis of confirmed cases of human influenza virus (HIFV), human respiratory syncytial virus (HRSV), and human metapneumovirus (HMPV) was conducted to describe their clinical and epidemiological characteristics. During 2009-2021, active surveillance of acute respiratory infections (ARIs) was performed in nine provinces of China. Clinical and epidemiological information and laboratory testing results of HIFV, HRSV, and HMPV were analyzed. Among 11591 ARI patients, the single-infection rates of HIFV, HRSV, and HMPV were 15.00%, 9.59%, and 2.24%, respectively; the coinfection rate of these three viruses was 0.64%. HIFV infection was mainly in adults aged 15-59 years, accounting for 39.10%. HRSV and HMPV infections were mainly in children under 5 years old, accounting for 87.13% and 83.46%, respectively. Patients with HRSV infection were younger than HMPV. HRSV and HMPV had high similarities in clinical manifestations, presenting with lower respiratory symptoms. HIFV mainly presented with an upper respiratory infection. The epidemic peak of HRSV was earlier than that of HIFV, and that of HMPV was later than those of HRSV and HFIV. A total of 85.14% of coinfection cases were children under 5 years old. Coinfection might increase the risk of pneumonia in HIFV cases. During 2020-2021, the positive rates and seasonal patterns of these three viruses changed due to the impact of the COVID-19 pandemic. Certain clinical and epidemiological features were observed in HIFV, HRSV, and HMPV infections, which could be beneficial for guiding clinical diagnosis, treatment, and prevention of these three viruses in China.

Transmission Dynamics of the Rubella Virus Circulating in China During 2010-2019: 2 Lineage Switches Between Genotypes 1E and 2B.

BACKGROUND: To provide a better understanding of the progress on rubella control and elimination in China, a genetic analysis was conducted to examine the transmission pattern of the endemic rubella virus in China during 2010-2019. METHODS: A total of 4895 strains were obtained from 29 of the 31 provinces in mainland China during 2010-2019. The genotyping regions of the strains were amplified, determined, and assembled. Genotyping analysis and lineage division were performed by comparisons with the World Health Organization reference strains and reported lineage reference strains, respectively. Further phylogenetic analyses were performed to compare the genetic relationship. RESULTS: During 2010-2019, the domestic lineage 1E-L1 and multiple imported lineages of rubella viruses including 2B-L1, 1E-L2, and 2B-L2c were identified. Further analysis of the circulation trend of the different lineages indicated that 2 switches occurred among the lineages. The first shift was from lineage 1E-L1 to 2B-L1, which occurred around 2015-2016, followed by the lowest rubella incidence in 2017. The second shift was from lineage 2B-L1 to 1E-L2 and 2B-L2c, which occurred around 2018-2019, coinciding with rubella resurgence and the subsequent nationwide epidemic during 2018-2019. Insufficient genomic information worldwide made it impossible to trace the origin of the imported viruses. CONCLUSIONS: China was moving toward rubella elimination, as evidenced by the fact that previous endemic lineages were not detected. However, rubella reemerged in 2018 2019 due to the newly imported rubella viruses. Therefore, to realize the rubella elimination goal, joint efforts are required for all countries worldwide.

Emerging Human Metapneumovirus Gene Duplication Variants in Patients with Severe Acute Respiratory Infection, China, 2017-2019.

We detected human metapneumovirus (HMPV) in 72 (7.1%) of 1,021 patients hospitalized with severe acute respiratory infection in Luohe, China, during 2017-2019. We detected HMPV most frequently in young children and less often in adults. HMPV genotype A2c variants 111 nt and 180 nt duplications predominated, demonstrating their continuing geographic spread.

Genetic analysis of human parainfluenza virus type 4 associated with severe acute respiratory infection in children in Luohe City, Henan Province, China, during 2017-2018.

During 2017-2018, nasopharyngeal aspirates (NPAs) from 627 hospitalized patients with severe acute respiratory infection at Luohe Center Hospital were tested by RT-PCR for human parainfluenza virus 4 (HPIV-4). Fourteen (2.2%) of the 627 samples were positive for HPIV-4. The complete HN gene was amplified from nine positive samples and sequenced. Sequence comparisons showed that the HPIV-4 strains circulating in the city of Luohe are closely related to HPIV-4A strains. Our study indicated that there were multiple lineages of HPIV-4 circulating in Henan Province in China during the study period. This will improve our understanding of the epidemiological and clinical characteristics of HPIV-4.

Measles Vaccine-Associated Rash Illness in China: an Emerging Issue in the Process of Measles Elimination.

Along with the implementation of measles case-based surveillance, measles vaccine-associated rash illness (VARI) cases were detected in China. To better understand the characteristics of VARI, 101 VARI cases confirmed by measles virus genotyping in 2011 to 2018 were analyzed in this study. With the decrease in measles incidence, the detection rate of VARI cases increased among the cases confirmed by genotyping. Compared with genotype H1 wild-type measles, VARI occurred throughout the year, without obvious seasonal distribution. Infants and children of ages 8 to 23 months were the main population of VARI. VARI mainly occurred within 14 days after measles vaccination. The number of VARI cases peaked on the 8th day after measles vaccination, which was later than that of genotype H1 wild-type measles cases with a measles vaccination history. VARI presents clinical symptoms similar to those of measles. The frequencies of the "3Cs" (cough, coryza, and conjunctivitis), Koplik spots, and complications in VARI cases were significantly lower than those in wild-type measles cases. In total, 94.06% of sequences from VARI cases were identical to measles vaccine strain S191 in the C-terminal 450-nucleotide sequence of the nucleoprotein (N-450) gene. A few substitutions were found in N-450 sequences of the VARI cases. The confirmation of VARI has become an emerging issue in the process of measles elimination. Rapid confirmation of VARI is critical for measles surveillance and will help to determine the response measures for measles, especially in measles preelimination and elimination settings. The suspected measles cases with measles-containing vaccine (MCV) vaccination were recommended to be tested by the laboratory to identify wild-type measles or VARI.

The nucleic acid positive rate and genotype distribution of human cytomegalovirus in human milk banks in China.

To determine the status of human cytomegalovirus (HCMV) infection in human milk in China, a total of 510 human milk samples obtained from three provinces, including 211 donor human milk samples from human milk banks and 299 milk samples obtained from the mothers of premature infants, were tested to detect HCMV DNA. Overall, 46.4% of the donated milk samples and 59.2% of the samples obtained from mothers of premature infants were positive for HCMV DNA. The concentration of HCMV DNA was approximately 103 -104 copies/ml in the HCMV-DNA-positive human milk samples. Based on the nucleotide sequence of a 299- to 305-bp fragment of the glycoprotein B (gB) gene, three HCMV genotypes (gB1, gB2 and gB3) were identified in human milk samples. Mixed infection with genotypes gB1 and gB3 was also found in four milk samples from mothers. Genotype gB1 was the predominant genotype in the HCMV-DNA-positive human milk samples, and it could be subdivided into three lineages. There were also some characteristic nucleotides and amino acids in the three HCMV genotypes, which were helpful for distinguishing the genotypes. This is the first study to clarify the HCMV infection status and genetic characteristics of human milk obtained from banks in China, which will be helpful in preventing postnatal HCMV infections and ensuring the safety of human milk banks.

Downregulation of miR-493 promoted melanoma proliferation by suppressing IRS4 expression.

Accumulating evidence indicated that aberrantly expressed microRNAs play critical roles in the initiation and progression of human cancers. However, the underlying functions of miR-493 in human melanoma remains unknown. Here, our study found that miR-493 expression was downregulated in human melanoma tissues and cells. Overexpression of miR-493 suppressed cell proliferation and cell cycle in human melanoma cell line A375. IRS4 was defined as a target for downregulation by miR-493 and was confirmed by luciferase assay. We also found that knockdown of IRS4 counteracted the proliferation promotion by miR-493 inhibitor. In summary, these results demonstrated that miR-493 acts as a tumor suppressor and inhibits cell proliferation and cell cycle in human melanoma by directly targeting IRS4.

Nationwide distribution of varicella-zoster virus clades in China.

BACKGROUND: In 2010, a universal nomenclature for varicella-zoster virus (VZV) clades was established, which is very useful in the monitoring of viral evolution, recombination, spread and genetic diversity. Currently, information about VZV clades has been disclosed worldwide, however, there are limited data regarding the characterization of circulating VZV clades in China, even where varicella remains widely epidemic. METHODS: From 2008 to 2012, clinical samples with varicella or zoster were collected in General Hospital in eight provinces and analyzed by PCR, restriction endonuclease digestion and sequencing. The viral clades were determined by analysis of five single nucleotide polymorphisms (SNPs) within the 447-bp fragment of open reading frame (ORF) 22, and the restriction fragment length polymorphisms (RFLPs) of ORF 38 (PstI), ORF 54 (BglI) and ORF 62 (SmaI) were evaluated to understand genetic diversity of VZV and determinate varicella vaccine adverse event (VVAE). RESULTS: Seventy-seven varicella and 11 zoster samples were identified as being positive for VZV. The five SNPs profile showed that the majority of VZV strains belonged to clade 2, but clade 5 and clade 4 strains were also found in Guangdong. The RFLPs analysis of the DNA fragments of ORF 38, 54 and 62 showed that 85 of these samples were characterized as PstI + BglI + SamI-, and the remaining three VZV strains from varicella patients were characterized as PstI-BglI + SamI+ which is the genetic profile of VVAEs. CONCLUSIONS: The study suggested that the predominant clade 2 VZVs had been continually circulating since at least the 1950s in China. Nearly all VZV strains except VVAEs possessed the genetic profile of PstI + BglI + Sam-. However, the other clades were also found to be co-circulating with clade 2, especially in the border regions. These results highlighted the need for the constant and broad use of virologic surveillance to provide an important genetic baseline for varicella control and vaccination programs in China.

Slow magnetization relaxation in Ni(II)Dy(III)Fe(III) molecular cycles.

Two cyano- and phenoxo-bridged hexanuclear Ni(II)2Dy(III)2Fe(III)2 (1) and octanuclear Ni(II)4Dy(III)2Fe(III)2 (2) trimetallic cyclic complexes have been obtained. They are the first trimetallic metallocycles. Magnetic studies reveal that 1 and 2 exhibit single-molecule-magnet behavior with an energy barrier of 17.9 K for complex 1 in a 2000 Oe static field and 25.0 K for complex 2 in a zero static field.

Sineoculis homeobox homolog 1 protein as an independent biomarker for gastric adenocarcinoma.

Sine oculis homeobox homolog 1 (SIX1) protein is a member of the homeobox transcription factor family. Overexpression of SIX1 contributes to cancer progression and is associated with adverse outcomes in various cancer types including breast, ovarian, uterine cervical and liver. To investigate the clinicopathological significance of SIX1 protein expression in gastric adenocarcinomas (GAC), localization of the SIX1 protein was determined in MKN-1, a gastric cancer cell line, using immunofluorescence (IF) staining; SIX1 mRNA level was detected in fresh tissues of GAC and normal gastric mucosa using quantitative real-time polymerase chain reaction (qRT-PCR); and SIX1 protein expression was assessed in 163 GAC, 35 gastric dysplasia and 26 normal gastric mucosa using immunohistochemical (IHC) staining. Correlations between SIX1 protein expression and pathological parameters of GAC were analyzed using Chi-square tests, differences in survival curves were analyzed using log-rank tests, and multivariate survival analysis was performed using the Cox proportional hazards regression model. SIX1 protein showed a mainly cytoplasmic staining pattern in GAC using IF and IHC staining. The positive SIX1 protein expression rate was 80.4% in GAC, which was significantly higher than in either gastric dysplasia (45.7%) or normal gastric mucosa (26.9%) (P<0.01). qRT-PCR data also confirmed increased levels of SIX1 mRNA expression in GAC compared with the normal gastric mucosa in fresh tissues. In addition, the strongly positive SIX1 protein expression rate was significantly correlated with clinical stage, lymph node metastasis and serosal invasion of GAC (P<0.01 or P<0.05), while there was no association with gender, age, tumor size, Lauren classification or histological types of GAC. Notably, strongly positive signals were frequently observed in tumor blood vessels and/or lymphatic vessels. GAC patients with high expression of the SIX1 had shorter overall and disease-free survival rates than those with low SIX1 protein expression (P<0.01). Furthermore, using multivariate analysis, SIX1 protein expression was found to be an independent risk factor for survival in patients with GAC along with clinical stage and serosal invasion (P<0.01). In conclusion, SIX1 protein expression status may be an independent biomarker for prognostic evaluation of GAC.

Toward higher nuclearity: tetranuclear cobalt(II) metallogrid exhibiting spin crossover.

Supramolecular strategy was employed to achieve the highest nuclearity Co(II) cluster exhibiting spin-crossover (SCO) behavior. Magnetic susceptibility characterization of the Co4(II) complex shows that two different spin-transition processes occur. The SCO behavior is directed by the partially deprotonated polydentate ligand, which favors the structural distortion required by the spin transition.

NCPAD2 is a favorable predictor of prognostic and immunotherapeutic biomarker for multiple cancer types including lung cancer.

BACKGROUND: Non-SMC condensin I complex subunit D2 (NCAPD2) belongs to the chromosomal structural maintenance family. While the different contribution of NCAPD2 to chromosome in mitosis have been thoroughly investigated, much less is known about the expression of NCAPD2 in pan-cancer. Thus, we used a bioinformatics dataset to conduct a pan-cancer analysis of NCAPD2 to determine its regulatory role in tumors. METHODS: Multiple online databases were analyzed NCAPD2 gene expression, protein level, patient survival and functional enrichment in pan-cancer. Genetic alteration and tumor stemness of NCAPD2 were analyzed using cBioPortal and SangerBox. The GSCA and CellMiner were used to explore the relationship between NCAPD2 and drug sensitivity. The diagnostic value of prognosis was evaluated by ROC curve. Subsequently, the immune infiltration level and immune subtype of NCAPD2 in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) were analyzed using TIMER1 and TISIDB. RESULTS: NCAPD2 gene expression was significantly higher in most cancers and associated with clinical stage and poor prognosis. Genomic heterogeneity of NCAPD2 promoted the occurrence and development of tumors. GO enrichment analysis suggested NCAPD2 might be involved in DNA repair and immune response. NCAPD2 was involved in immune infiltration of LUAD and LUSC. ROC curves showed that NCAPD2 has important prognosis diagnostic value in LUAD and LUSC. Moreover, NCAPD2 was drug sensitive to topotecan, which may be an optimize immunotherapy. CONCLUSIONS: It was found that NCAPD2 was overexpressed in pan-cancers, which was associated with poor outcomes. Importantly, NCAPD2 could be a diagnostic marker and an immune related biomarker for LUAD and LUSC.

Seasonal and Genetic Characteristics of Human Metapneumovirus Circulating - Henan Province, China, 2017-2023.

Introduction: This study examines the seasonal and genetic characteristics of human metapneumovirus (HMPV) in Henan from 2017 to 2023. Methods: Samples from patients with acute respiratory infection (ARI) testing positive for HMPV were subjected to real-time reverse transcription polymerase chain reaction The G gene was amplified and sequenced from these samples for epidemiological and phylogenetic analysis. Results: We enrolled 2,707 ARI patients from October 2017 to March 2023, finding an HMPV positivity rate of 6.17% (167/2,707). Children under five exhibited the highest infection rate at 7.78% (138/1,774). The 2018 and 2019 HMPV outbreaks predominantly occurred in spring (March to May), with peak positivity rates of 31.11% in May 2018 and 19.57% in May 2019. A notable increase occurred in November 2020, when positivity reached a historic high of 42.11%, continuing until January 2021. From February 2021 through March 2023, no significant seasonal peaks were observed, with rates ranging from 0% to 8.70%. Out of 81 G gene sequences analyzed, 46.91% (38/81) were identified as subtype A (A2c: 45.67%, 37/81; A2b: 1.23%, 1/81) and 53.09% (43/81) as subtype B (B1: 9.88%, 8/81; B2: 43.21%, 35/81). Notably, an AAABBA switch pattern was observed in HMPV subtypes. The dominant strains were A2c111nt-dup in subtype A and B2 in subtype B. Conclusions: Six years of surveillance in Henan Province has detailed the seasonal and genetic dynamics of HMPV, contributing valuable insights for the control and prevention of HMPV infections in China. These findings support the development of targeted HMPV vaccines and immunization strategies.

Epidemiological Characteristics of Human Parainfluenza Viruses Infections - China, 2019-2023.

Introduction: A retrospective study based on sentinel surveillance was conducted in 10 provincial-level administrative divisions (PLADs) in China to enhance the understanding of the epidemiological characteristics of human parainfluenza viruses (HPIVs). Methods: From January 2019 to June 2023, respiratory specimens were collected from individuals with acute respiratory infections (ARIs) and screened for four HPIVs serotypes and other common respiratory viruses using multiplex real-time polymerase chain reaction (PCR). This study analyzed the association of HPIVs infections with seasonal patterns, geographical distribution, demographic profiles, clinical features, and co-infection status. Results: During the study period, a total of 12,866 ARIs were included. The overall detection rate of HPIVs was 6.15%, varying from 5.04% in 2022 to 9.70% in 2020. The median age of HPIVs-infected patients was 3 years. HPIV2 was more prevalent among individuals aged 5-17 years (42.57%), while HPIV4 was more common in those over 65 years (12.24%). HPIV3 (54.16%) and HPIV1 (27.18%) were the predominant serotypes, and their prevalence exhibited significant seasonal fluctuations post- coronavirus disease 2019 (COVID-19) pandemic. The peak of HPIV3 shifted three months later in 2020 compared to 2019 and returned to a summer peak thereafter. Two peaks of HPIV1 were observed in 2021 following the peak of HPIV3. Additionally, co-infections were frequent in HPIVs cases (overall rate: 22.12%), with human rhinovirus being the most common co-infecting virus. Conclusions: The prevalence of HPIVs in China was predominantly due to HPIV3 and HPIV1, and their seasonal patterns were altered by pandemic restrictions. Hence, continuous surveillance of HPIVs is essential.

Spin transitions in Fe(II) metallogrids modulated by substituents, counteranions, and solvents.

Two bis(tridentate) Schiff base ligands H2L(x) were used to construct three 2×2 grid-type tetranuclear Fe(II) complexes 1-3 to obtain polynuclear spin-crossover materials. Magnetic susceptibility measurements show that the spin states of the complexes are related to the substituents of H2L(x), and that spin transition occurs only in complexes 1 and 2, which are derived from a bulky ligand, whereas complex 3 is diamagnetic. The transition temperatures of complexes 1 and 2 are close to room temperature and are dependent on counteranions. The spin transition of complex 1 can be reversibly tuned by the dehydration and hydration process.