[Efficacy of Barbed reposition pharyngoplasty combined with Han-Uvulopalatopharyngoplasty for the treatment of OSAHS patients]

Objective: To study the efficacy of Barbed reposition pharyngoplasty (BRP) combined with Han-Uvulopalatopharyngoplasty (H-UPPP) in surgical treatment of OSAHS patients. Methods: OSAHS patients admitted to our department from June 2021 to February 2022 who met the surgical enrollment criteria were divided into two groups by surgical procedure: H-UPPP operation group [Control group, 47 cases, including 42 males and 5 females, aged 18-64 (37.77±11.65)years, and H-UPPP+BRP group [Study group, 48 cases, including 45 males and 3 females, aged 23-60 (39.10±9.86) years]. The surgical efficacy 6 months after operation was retrospectively analyzed. Meanwhile, the relationship between the surgical efficacy and modified Friedman pharyngeal anatomical stages was analyzed. The postoperative pain VAS score at first 3 days and the incidence of foreign body sensation in pharynx after 6 months of operation were compared between the two groups. Statistical analysis was conducted by SPSS 23.0. Results: There were no significant differences in gender, age, BMI, Friedman pharyngeal anatomical stages, ESS score, AHI and LSpO2 between the two groups, preoperatively (P>0.05). There was significant difference between the two groups in ratio of cumulative time of oxygen saturation below 90% to total sleep time(CT90), preoperatively. Surgical efficacy of H-UPPP operation group was 48.9% (23/47), while H-UPPP+BRP operation group was 70.8% (34/48), which was statistically significant (χ2=4.74, P=0.029). H-UPPP+BRP group seemed to have a higher surgical efficacy than H-UPPP group in patients with Friedman Ⅱb (87% vs. 61.9%) and Ⅲ stage (44.4% vs. 15%), but there was no statistically significant difference (P>0.05). H-UPPP+BRP group had a higher pain VAS score in first three days (t=-3.10, P=0.003), also had higher incidence of pharyngeal foreign body sensation after 6 months of operation (χ2=4.727, P=0.030). Conclusions: In the surgical treatment of OSAHS patients, the overall efficacy of BRP combined H-UPPP surgery is higher than that of H-UPPP surgery alone. It may be more suitable for OSAHS patients with modified Friedman type Ⅱb and type Ⅲ stage.

Preventive and therapeutic benefits of nelfinavir in rhesus macaques and human beings infected with SARS-CoV-2

Effective drugs with broad spectrum safety profile to all people are highly expected to combat COVID-19 caused by SARS-CoV-2. Here we report that nelfinavir, an FDA approved drug for the treatment of HIV infection, is effective against SARS-CoV-2 and COVID-19. Preincubation of nelfinavir could inhibit the activity of the main protease of the SARS-CoV-2 (IC₅₀ = 8.26 μM), while its antiviral activity in Vero E6 cells against a clinical isolate of SARS-CoV-2 was determined to be 2.93 μM (EC₅₀). In comparison with vehicle-treated animals, rhesus macaque prophylactically treated with nelfinavir had significantly lower temperature and significantly reduced virus loads in the nasal and anal swabs of the animals. At necropsy, nelfinavir-treated animals had a significant reduction of the viral replication in the lungs by nearly three orders of magnitude. A prospective clinic study with 37 enrolled treatment-naive patients at Shanghai Public Health Clinical Center, which were randomized (1:1) to nelfinavir and control groups, showed that the nelfinavir treatment could shorten the duration of viral shedding by 5.5 days (9.0 vs. 14.5 days, P = 0.055) and the duration of fever time by 3.8 days (2.8 vs. 6.6 days, P = 0.014) in mild/moderate COVID-19 patients. The antiviral efficiency and clinical benefits in rhesus macaque model and in COVID-19 patients, together with its well-established good safety profile in almost all ages and during pregnancy, indicated that nelfinavir is a highly promising medication with the potential of preventative effect for the treatment of COVID-19.

A tandem-repeat dimeric RBD protein-based covid-19 vaccine zf2001 protects mice and nonhuman primates

Safe, efficacious, and deployable vaccines are urgently needed to control COVID-19 in the large-scale vaccination campaigns. We report here the preclinical studies of an approved protein subunit vaccine against COVID-19, ZF2001, which contains tandem-repeat dimeric receptor-binding domain (RBD) protein with alum-based adjuvant. We assessed vaccine immunogenicity and efficacy in both mice and non-human primates (NHPs). ZF2001 induced high levels of RBD-binding and SARS-CoV-2 neutralizing antibody in both mice and non-human primates, and elicited balanced T_H1/T_H2 cellular responses in NHPs. Two doses of ZF2001 protected Ad-hACE2-transduced mice against SARS-CoV-2 infection, as detected by reduced viral RNA and relieved lung injuries. In NHPs, vaccination of either 25 μg or 50 μg ZF2001 prevented infection with SARS-CoV-2 in lung, trachea, and bronchi, with milder lung lesions. No evidence of disease enhancement was observed in both animal models. ZF2001 has been approved for emergency use in China, Uzbekistan, Indonesia, and Columbia. The high safety, immunogenicity, and protection efficacy in both mice and NHPs found in this preclinical study was consistent with the results in human clinical trials.

Single-nucleus transcriptomic profiling of multiple organs in a rhesus macaque model of SARS-CoV-2 infection

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes diverse clinical manifestations and tissue injuries in multiple organs. However, cellular and molecular understanding of SARS-CoV-2 infection-associated pathology and immune defense features in different organs remains incomplete. Here, we profiled approximately 77 000 single-nucleus transcriptomes of the lung, liver, kidney, and cerebral cortex in rhesus macaques ( Macaca mulatta) infected with SARS-CoV-2 and healthy controls. Integrated analysis of the multi-organ dataset suggested that the liver harbored the strongest global transcriptional alterations. We observed prominent impairment in lung epithelial cells, especially in AT2 and ciliated cells, and evident signs of fibrosis in fibroblasts. These lung injury characteristics are similar to those reported in patients with coronavirus disease 2019 (COVID-19). Furthermore, we found suppressed MHC class I/II molecular activity in the lung, inflammatory response in the liver, and activation of the kynurenine pathway, which induced the development of an immunosuppressive microenvironment. Analysis of the kidney dataset highlighted tropism of tubule cells to SARS-CoV-2, and we found membranous nephropathy (an autoimmune disease) caused by podocyte dysregulation. In addition, we identified the pathological states of astrocytes and oligodendrocytes in the cerebral cortex, providing molecular insights into COVID-19-related neurological implications. Overall, our multi-organ single-nucleus transcriptomic survey of SARS-CoV-2-infected rhesus macaques broadens our understanding of disease features and antiviral immune defects caused by SARS-CoV-2 infection, which may facilitate the development of therapeutic interventions for COVID-19.

Characteristics of replication and pathogenicity of SARS-CoV-2 Alpha and Delta isolates

The continuously arising of SARS-CoV-2 variants has been posting a great threat to public health safety globally, from B.1.17 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.617.2 (Delta) to B.1.1.529 (Omicron). The emerging or re-emerging of the SARS-CoV-2 variants of concern is calling for the constant monitoring of their epidemics, pathogenicity and immune escape. In this study, we aimed to characterize replication and pathogenicity of the Alpha and Delta variant strains isolated from patients infected in Laos. The amino acid mutations within the spike fragment of the isolates were determined via sequencing. The more efficient replication of the Alpha and Delta isolates was documented than the prototyped SARS-CoV-2 in Calu-3 and Caco-2 ​cells, while such features were not observed in Huh-7, Vero E6 and HPA-3 ​cells. We utilized both animal models of human ACE2 (hACE2) transgenic mice and hamsters to evaluate the pathogenesis of the isolates. The Alpha and Delta can replicate well in multiple organs and cause moderate to severe lung pathology in these animals. In conclusion, the spike protein of the isolated Alpha and Delta variant strains was characterized, and the replication and pathogenicity of the strains in the cells and animal models were also evaluated.

Specific inhibition of the NLRP3 inflammasome suppresses immune overactivation and alleviates COVID-19 like pathology in mice

Background

The Coronavirus Disease 2019 (COVID-19) pandemic has been a great threat to global public health since 2020. Although the advance on vaccine development has been largely achieved, a strategy to alleviate immune overactivation in severe COVID-19 patients is still needed. The NLRP3 inflammasome is activated upon SARS-CoV-2 infection and associated with COVID-19 severity. However, the processes by which the NLRP3 inflammasome is involved in COVID-19 disease remain unclear.

Methods

We infected THP-1 derived macrophages, NLRP3 knockout mice, and human ACE2 transgenic mice with live SARS-CoV-2 in Biosafety Level 3 (BSL-3) laboratory. We performed quantitative real-time PCR for targeted viral or host genes from SARS-CoV-2 infected mouse tissues, conducted histological or immunofluorescence analysis in SARS-CoV-2 infected mouse tissues. We also injected intranasally AAV-hACE2 or intraperitoneally NLRP3 inflammasome inhibitor MCC950 before SARS-CoV-2 infection in mice as indicated.

Findings

We have provided multiple lines of evidence that the NLRP3 inflammasome plays an important role in the host immune response to SARS-CoV-2 invasion of the lungs. Inhibition of the NLRP3 inflammasome attenuated the release of COVID-19 related pro-inflammatory cytokines in cell cultures and mice. The severe pathology induced by SARS-CoV-2 in lung tissues was reduced in Nlrp3^−/− mice compared to wild-type C57BL/6 mice. Finally, specific inhibition of the NLRP3 inflammasome by MCC950 alleviated excessive lung inflammation and thus COVID-19 like pathology in human ACE2 transgenic mice.

Interpretation

Inflammatory activation induced by SARS-CoV-2 is an important stimulator of COVID-19 related immunopathology. Targeting the NLRP3 inflammasome is a promising immune intervention against severe COVID-19 disease.

Funding

This work was supported by grants from the Bureau of Frontier Sciences and Education, CAS (grant no. QYZDJ-SSW-SMC005 to Y.G.Y.), the key project of the CAS “Light of West China” Program (to D.Y.) and Yunnan Province (202001AS070023 to D.Y.).

[Different concentrations of specialized pro-resolving mediators in eosinophilic and non-eosinophilic chronic rhinosinusitis with nasal polyps]

Objective: To investigate the difference of concentrations of specialized pro-resolving mediators (SPMs) derived from fatty acids in eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) and non-eosinophilic chronic rhinosinusitis with nasal polyps (nECRSwNP). Methods: A total of 36 patients with bilateral chronic rhinosinusitis with nasal polyps (CRSwNP) who underwent endoscopic nasal surgeries in Peking Union Medical College Hospital from May 2019 to September 2020 were enrolled, including 27 males and 9 females, with the age from 13 to 67 years. There were 23 cases of ECRSwNP and 13 cases of nECRSwNP. At the same time, 12 control subjects were enrolled. The concentrations of multiple SPMs, including lipoxins (LXA₄ and LXB₄), resolvins (RvD₁, RvD₂, RvD₃, RvD₅ and RvE₁), protectins (PDX) and maresins (Mar-1) in nasal polyps with different histological subtypes and normal nasal mucosa were analyzed using liquid chromatography-tandem mass spectrometry. The concentrations of SPMs between groups were compared using Mann-Whitney U test. Spearman's rank correlation coefficient was used to measure the correlation between the concentrations of SPMs in nasal polyps and tissue eosinophil counts. Results: The concentrations of RvD₂, RvD₃, RvD₅, LXA₄, LXB₄, Mar-1 and PDX in ECRSwNP group were significantly higher than that in controls (Z value was -2.276, -2.313, -3.371, -2.094, -2.051, -3.104 and -2.294, respectively, all P<0.05). The concentrations of RvD₂, RvD₅, Mar-1 and PDX in ECRSwNP group were significantly higher than those in nECRSwNP group (Z value was -2.175, -2.289, -2.243 and -2.124, respectively, all P<0.05). There was no significant difference in all these SPMs between nECRSwNP and controls (all P>0.05). The concentrations of RvD₂, RvD₃, RvD₅, LXB₄, Mar-1 and PDX in nasal polyps correlated positively with tissue eosinophil counts (r value was 0.443, 0.436, 0.371, 0.502, 0.340 and 0.386, respectively, all P<0.05). Conclusions: A varienty of SPMs are elevated in ECRSwNP. Dysregulation of fatty acid metabolism might play an important role in the chronic inflammation of ECRSwNP.

Pro-inflammatory microenvironment and systemic accumulation of CXCR3+ cell exacerbate lung pathology of old rhesus macaques infected with SARS-CoV-2

Understanding the pathological features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in an animal model is crucial for the treatment of coronavirus disease 2019 (COVID-19). Here, we compared immunopathological changes in young and old rhesus macaques (RMs) before and after SARS-CoV-2 infection at the tissue level. Quantitative analysis of multiplex immunofluorescence staining images of formalin-fixed paraffin-embedded (FFPE) sections showed that SARS-CoV-2 infection specifically induced elevated levels of apoptosis, autophagy, and nuclear factor kappa-B (NF-κB) activation of angiotensin-converting enzyme 2 (ACE2)+ cells, and increased interferon α (IFN-α)- and interleukin 6 (IL-6)-secreting cells and C-X-C motif chemokine receptor 3 (CXCR3)+ cells in lung tissue of old RMs. This pathological pattern, which may be related to the age-related pro-inflammatory microenvironment in both lungs and spleens, was significantly correlated with the systemic accumulation of CXCR3+ cells in lungs, spleens, and peripheral blood. Furthermore, the ratio of CXCR3+ to T-box protein expression in T cell (T-bet)+ (CXCR3+/T-bet+ ratio) in CD8+ cells may be used as a predictor of severe COVID-19. These findings uncovered the impact of aging on the immunopathology of early SARS-CoV-2 infection and demonstrated the potential application of CXCR3+ cells in predicting severe COVID-19.

A recombinant receptor-binding domain in trimeric form generates protective immunity against SARS-CoV-2 infection in nonhuman primates

A safe and effective vaccine is critical to combat the COVID-19 pandemic. Here, we developed a trimeric SARS-CoV-2 receptor-binding domain (RBD) subunit vaccine candidate that simulates the natural structure of the spike (S) trimer glycoprotein. Immunization with the RBD trimer-induced robust humoral and cellular immune responses, and a high level of neutralizing antibodies was maintained for at least 4.5 months. Moreover, the antibodies that were produced in response to the vaccine effectively cross-neutralized the SARS-CoV-2 501Y.V2 variant (B.1.351). Of note, when the vaccine-induced antibodies dropped to a sufficiently low level, only one boost quickly activated the anamnestic immune response, conferring full protection against a SARS-CoV-2 challenge in rhesus macaques without typical histopathological changes in the lung tissues. These results demonstrated that the SARS-CoV-2 RBD trimer vaccine candidate is highly immunogenic and safe, providing long-lasting, broad, and significant immunity protection in nonhuman primates, thereby offering an optimal vaccination strategy against COVID-19.

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A SARS-CoV-2 trimeric vaccine candidate demonstrates safe, long-lasting, broad, and significant immunity protection in nonhuman primates

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The vaccine-induced antibodies can effectively neutralize the SARS-CoV-2 501Y.V2 variant

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A booster vaccination can quickly activate the memory immune response to avoid re-infection

Northern pig-tailed macaques ( Macaca leonina) infected with SARS-CoV-2 show rapid viral clearance and persistent immune response

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), has become an unprecedented global health emergency. At present, SARS-CoV-2-infected nonhuman primates are considered the gold standard animal model for COVID-19 research. Here, we showed that northern pig-tailed macaques ( Macaca leonina, NPMs) supported SARS-CoV-2 replication. Furthermore, compared with rhesus macaques, NPMs showed rapid viral clearance in lung tissues, nose swabs, throat swabs, and rectal swabs, which may be due to higher expression of interferon (IFN)-α in lung tissue. However, the rapid viral clearance was not associated with good outcome. In the second week post infection, NPMs developed persistent or even more severe inflammation and body injury compared with rhesus macaques. These results suggest that viral clearance may have no relationship with COVID-19 progression and SARS-CoV-2-infected NPMs could be considered as a critically ill animal model in COVID-19 research.

S-Trimer, a COVID-19 subunit vaccine candidate, induces protective immunity in nonhuman primates

SARS-CoV-2 is the underlying cause for the COVID-19 pandemic. Like most enveloped RNA viruses, SARS-CoV-2 uses a homotrimeric surface antigen to gain entry into host cells. Here we describe S-Trimer, a native-like trimeric subunit vaccine candidate for COVID-19 based on Trimer-Tag technology. Immunization of S-Trimer with either AS03 (oil-in-water emulsion) or CpG 1018 (TLR9 agonist) plus alum adjuvants induced high-level of neutralizing antibodies and Th1-biased cellular immune responses in animal models. Moreover, rhesus macaques immunized with adjuvanted S-Trimer were protected from SARS-CoV-2 challenge compared to vehicle controls, based on clinical observations and reduction of viral loads in lungs. Trimer-Tag may be an important platform technology for scalable production and rapid development of safe and effective subunit vaccines against current and future emerging RNA viruses.

S-Trimer, a COVID-19 subunit vaccine candidate, induces protective immunity in nonhuman primates

SARS-CoV-2 is the underlying cause for the COVID-19 pandemic. Like most enveloped RNA viruses, SARS-CoV-2 uses a homotrimeric surface antigen to gain entry into host cells. Here we describe S-Trimer, a native-like trimeric subunit vaccine candidate for COVID-19 based on Trimer-Tag technology. Immunization of S-Trimer with either AS03 (oil-in-water emulsion) or CpG 1018 (TLR9 agonist) plus alum adjuvants induced high-level of neutralizing antibodies and Th1-biased cellular immune responses in animal models. Moreover, rhesus macaques immunized with adjuvanted S-Trimer were protected from SARS-CoV-2 challenge compared to vehicle controls, based on clinical observations and reduction of viral loads in lungs. Trimer-Tag may be an important platform technology for scalable production and rapid development of safe and effective subunit vaccines against current and future emerging RNA viruses.

COVID-19-like symptoms observed in Chinese tree shrews infected with SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic continues to pose a global threat to the human population. Identifying animal species susceptible to infection with the SARS-CoV-2/ HCoV-19 pathogen is essential for controlling the outbreak and for testing valid prophylactics or therapeutics based on animal model studies. Here, different aged Chinese tree shrews (adult group, 1 year old; old group, 5-6 years old), which are close relatives to primates, were infected with SARS-CoV-2. X-ray, viral shedding, laboratory, and histological analyses were performed on different days post-inoculation (dpi). Results showed that Chinese tree shrews could be infected by SARS-CoV-2. Lung infiltrates were visible in X-ray radiographs in most infected animals. Viral RNA was consistently detected in lung tissues from infected animals at 3, 5, and 7 dpi, along with alterations in related parameters from routine blood tests and serum biochemistry, including increased levels of aspartate aminotransferase (AST) and blood urea nitrogen (BUN). Histological analysis of lung tissues from animals at 3 dpi (adult group) and 7 dpi (old group) showed thickened alveolar septa and interstitial hemorrhage. Several differences were found between the two different aged groups in regard to viral shedding peak. Our results indicate that Chinese tree shrews have the potential to be used as animal models for SARS-CoV-2 infection.

Delayed severe cytokine storm and immune cell infiltration in SARS-CoV-2-infected aged Chinese rhesus macaques

As of June 2020, Coronavirus Disease 2019 (COVID-19) has killed an estimated 440 000 people worldwide, 74% of whom were aged ≥65 years, making age the most significant risk factor for death caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. To examine the effect of age on death, we established a SARS-CoV-2 infection model in Chinese rhesus macaques ( Macaca mulatta) of varied ages. Results indicated that infected young macaques manifested impaired respiratory function, active viral replication, severe lung damage, and infiltration of CD11b + and CD8 + cells in lungs at one-week post infection (wpi), but also recovered rapidly at 2 wpi. In contrast, aged macaques demonstrated delayed immune responses with a more severe cytokine storm, increased infiltration of CD11b + cells, and persistent infiltration of CD8 + cells in the lungs at 2 wpi. In addition, peripheral blood T cells from aged macaques showed greater inflammation and chemotaxis, but weaker antiviral functions than that in cells from young macaques. Thus, the delayed but more severe cytokine storm and higher immune cell infiltration may explain the poorer prognosis of older aged patients suffering SARS-CoV-2 infection.

[Effects of different crystalloid fluids resuscitation on renal structure and function in sepsis rats]

To evaluate the effects of resuscitation with normal saline and sodium potassium magnesium calcium and glucose injection on renal structure and function in septic rats. Rat model of sepsis was established by ligation and perforation of cecum. Male SD rats were divided into four groups: sham operation group, sepsis group, saline resuscitation group, sodium potassium magnesium calcium and glucose injection resuscitation group. Blood gas analysis was performed at the end of resuscitation. The rats were sacrificed 72 hours after resuscitation. Blood samples were taken to measure the plasma levels of blood urea nitrogen (BUN), creatinine, interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factorα (TNFα). Caspase-3 expression was detected by immunohistochemistry in kidney sections. The degree of renal injury was evaluated by regular HE staining and electron microscope. Compared with normal saline resuscitation, sodium potassium calcium magnesium glucose injection resuscitation could decrease the levels of BUN, serum creatinine, IL-1β, IL-6 and TNFα (P<0.05) , reduce the expression of caspase-3 (P<0.05) , and improve the renal injury score (P<0.05) . Sodium potassium calcium magnesium glucose injection resuscitation can significantly improve the renal function of sepsis rats with less pathological damage of the kidney.

[Efficacy analysis of T type tube dilatation in adult cervical tracheal stenosis]

Objective:To investigate the efficacy, recurrence and strategy of T silicone tube dilatation for cicatricial stenosis of cervical trachea in adults.Method:Cinical data of 37 cases with the cervical tracheal stenosis were retrospectively analyzed, who were firstly treated by T shape silicone tube dilation for at least 10 months, from Jun 2006 to Jun 2016.Result:In 37 adult patients with cicatricial stenosis of the trachea, 29 cases were caused by tracheal intubation or incision, 6 cases were traumatic, and 2 cases were multiple osteochondritis. Twentythree cases were experienced one time surgery and extubated successfully, 8 cases were experienced 2 times and more than 2 times surgery (sternohyoid muscle flap pedicled hyoid bone with T tube expansion in 3 cases, tracheal endoscopic dilatation in 2 cases, T tube dilatation in 3 cases), extubation success rate of 83.7%. Among the 6 cases with failure of extubation, 2 cases were multiple osteochondritis, 3 cases had severe scar constitution, 1 cases were lost of follow-up.Conclusion:T type silicon tube expansion for the treatment of adult cervical tracheal stenosis can be achieved relatively high decannulation rate. For recurrent stenosis, we can consider to use various methods of expansion, and improve the decannulation rate. Intratracheal granulation tissuextubation after exbation should be observed for at least 1 month. For concurrent with polychondritis and severe scar the constitution, the operation should be carefully chosen.

Aikeqing decreases viral loads in SHIV89.6-infected Chinese rhesus macaques

BACKGROUND

Aikeqing (AKQ) has been shown in clinical studies to improve quality of life of HIV/AIDS patients, but anti-HIV activity has not been determined. The SHIV-infected macaque is an important animal model for testing antiviral drugs. This study aimed to determine the anti-HIV activity of AKQ in chronically SHIV89.6-infected Chinese rhesus macaques.

METHODS

Nine Chinese rhesus macaques were inoculated intravenously with SHIV89.6 virus. At 11 weeks post-infection, the animals were arbitrarily divided into three groups: high-dose (AKQ 1.65 g/kg; n = 3), low-dose (AKQ 0.55 g/kg; n = 3), and control (water 1 mL/kg; n = 3). Treatment was administered by the intragastric gavage route once-daily for 8 weeks. Blood (5 mL) was collected biweekly. Viral loads were analyzed by real-time quantitative RT-PCR assays, and T cell counts were monitored by FACS analyses throughout the treatment.

RESULTS

AKQ induced a persistent decline (P = 0.02) in plasma viral loads during treatment in the high-dose group compared with their baseline levels, and cessation of the therapy caused viral load rebound to the pretreatment levels. No significant difference (P = 0.06) was found in the plasma viral loads during treatment in the low-dose group. The CD4(+) T cell counts and CD4/CD8 ratios remained at stable high levels during the treatment period.

CONCLUSION

AKQ reduced plasma viral loads in the SHIV89.6-infected Chinese rhesus macaque model.

Sequence variation and gene duplication at the MHC DRB loci of the spotted seal Phoca largha

The major histocompatibility complex (MHC) is one of the most important genetic systems associated with resistance to infectious diseases in vertebrates. The spotted seal (Phoca largha) is one of the most endangered species in China. In this study, we present the first step in the molecular characterization of a DRB-like locus in the spotted seal by analyzing the nucleotide sequence of the polymorphic exon 2 segments, a 288-nucleotide sequence. By examining the segment from a group of 41 individuals, 28 alleles were identified. No deletion, insertion, or exceptional stop codon was detected, suggesting that these alleles could be functional in vivo. The nucleotide and amino acid sequences of the segment both showed a relatively high level of similarity (nucleotides 97%; amino acids 98%) to those of Meles meles and Zalophus californianus. The high level of spotted seal MHC-DRB polymorphism revealed in the present study has not been reported for the Phocidae and could be a consequence of the small spotted seal population adapting to the Bohai Sea, which probably has a relatively high level of pathogens.

Independent birth of a novel TRIMCyp in Tupaia belangeri with a divergent function from its paralog TRIM5

The origin of novel genes and their evolutionary fates are long-standing questions in evolutionary biology. These questions become more complicated for genes conserved across various lineages, such as TRIM5, an antiretroviral restriction factor and a retrovirus capsid sensor in immune signaling. TRIM5 has been subjected to numerous pathogenic challenges and undergone dynamic evolution, making it an excellent example for studying gene diversification. Previous studies among several species showed that TRIM5 gained genetic and functional novelty in a lineage-specific manner, either through gene duplication or a cyclophilin A retrotransposing into the TRIM5 locus, creating the gene fusion known as TRIM5-Cyclophilin A (TRIMCyp). To date, the general pattern of TRIM5 across the mammalian lineage remains elusive. In this study, we surveyed 36 mammalian genomes to verify a potentially novel TRIM5 pattern that uniquely seems to have occurred in tree shrews (Tupaia belangeri), and found that both gene duplication and retrotransposition worked jointly to form a specific TRIM5/TRIMCyp cluster not found among other mammals. Evolutionary analyses showed that tree shrew TRIMCyp (tsTRIMCyp) originated independently in comparison with previously reported TRIMCyps and underwent strong positive selection, whereas no signal of positive selection was detected for other tree shrew TRIM5 (tsTRIM5) genes. Functional assay results suggest a functional divergence between tsTRIMCyp and its closest paralog TRIM5-4, likely reflecting different fates under diverse evolutionary forces. These findings present a rare example of novel gene origination resulting from a combination of gene duplication, retrotransposition, and exon shuffling processes, providing a new paradigm to study genetic innovations and evolutionary fates of duplicated genes.

Molecular characterization, balancing selection, and genomic organization of the tree shrew (Tupaia belangeri) MHC class I gene

The major histocompatibility complex (MHC) class I genes play a pivotal role in the adaptive immune response among vertebrates. Accordingly, in numerous mammals the genomic structure and molecular characterization of MHC class I genes have been thoroughly investigated. To date, however, little is known about these genes in tree shrews, despite the increasingly popularity of its usage as an animal model. To address this deficiency, we analyzed the structure and characteristic of the tree shrew MHC class I genes (Tube-MHC I) and performed a comparative gene analysis of the tree shrew and other mammal species. We found that the full-length cDNA sequence of the tree shrew MHC class I is 1074bp in length. The deduced peptide is composed of 357 amino acids containing a leader peptide, an α1 and α2 domain, an α3 domain, a transmembrane domain and a cytoplasmic domain. Among these peptides, the cysteines, CD8(+) interaction and N-glycosylation sites are all well conserved. Furthermore, the genomic sequence of the tree shrew MHC class I gene was identified to be 3180bp in length, containing 8 exons and 7 introns. In 21 MHC class I sequences, we conducted an extensive study of nucleotide substitutions. The results indicated that in the peptide binding region (PBR) the rate of non-synonymous substitutions (dN) to synonymous substitutions (dS) was greater than 1, suggesting balancing selection at the PBR. These findings provide valuable contributions in furthering our understanding of the structure, molecular polymorphism, and function of the MHC class I genes in tree shrews, further improving their utility as an animal model in biomedical research.

Inhibitory effects of chloroquine on the activation of plasmacytoid dendritic cells in SIVmac239-infected Chinese rhesus macaques

It is currently widely accepted that immune activation in HIV-infected individuals leads to a severe loss of CD4⁺ T cells and the progression to AIDS. However, the underlying mechanism of this immune activation remains unclear. Experimental data suggest that the activation of plasmacytoid dendritic cells (pDCs) by plasma viremia may play a critical role in HIV-induced immune activation. In this study, we found that the level of immune activation was higher in the late phase of SIVmac239 infection compared with chronic infection, which suggests that immune activation might be related to disease progression in SIVmac239-infected non-human primate models. Our work also showed that chloroquine could effectively inhibit the activation of pDCs in vitro and in vivo. However, chloroquine treatment of SIVmac239-infected macaques had no significant influence on the Cellular composition of peripheral blood in these animals.

Intercomparison of methods for coincidence summing corrections in gamma-ray spectrometry--part II (volume sources)

The second part of an intercomparison of the coincidence summing correction methods is presented. This exercise concerned three volume sources, filled with liquid radioactive solution. The same experimental spectra, decay scheme and photon emission intensities were used by all the participants. The results were expressed as coincidence summing corrective factors for several energies of (152)Eu and (134)Cs, and different source-to-detector distances. They are presented and discussed.

[Epidemiological survey of a captive Chinese rhesus macaque breeding colony in Yunnan for SRV, STLV and BV]

Nonhuman primates are critical resources for biomedical research. Rhesus macaque is a popularly used laboratory nonhuman primate that share many characteristics with humans. However, rhesus macaques are the natural host of two exogenous retroviruses, SRV (simian type D retrovirus) and STLV (simian T lymphotropic virus). SRV and STLV may introduce potentially significant confounding factors into the study of AIDS model. Moreover, B virus (ceropithecine herpesvirus 1) is likely to harm not only rhesus macaque but also humans in experiments involving rhesus macaque. Yunnan province has large-scale breeding colonies of Chinese rhesus macaque. Therefore there is an urgent need for SPF Chinese rhesus macaque colonies. Here we investigated SRV, STLV and BV infections in 411 Chinese rhesus macaque by PCR technique. The results showed that the prevalence of SRV, STLV and BV among Chinese rhesus macaque breeding colony was 19.71% (81/411), 13.38% (55/411) and 23.11% (95/411), respectively. Comparison of viruses infection in different age-groups and male/female of Chinese rhesus macaque was also analyzed. This study will contribute to establishment of SPF Chinese rhesus macaque breeding colony.

Effect of plasma viremia on apoptosis and immunophenotype of dendritic cells subsets in acute SIVmac239 infection of Chinese rhesus macaques

Non-human primates such as Chinese rhesus macaques (Ch Rhs) provide good animal models for research on human infectious diseases. Similar to humans, there are two principal subsets of dendritic cells (DCs) in the peripheral blood of Ch Rhs: myeloid DCs (mDCs) and plasmacytoid DCs (pDCs). In this study, two-color fluorescence-activated cell sorting (FACS) analyses were used to identify the main DC subsets, namely CD1c(+) mDCs and pDCs from Ch Rhs. Then, the apoptosis and immunophenotype changes of DCs subsets were first described during the acute phase of SIVmac239 infection. Both the DCs subsets showed decreased CD4 expression and enhanced CCR5 expression; in particular, those of pDCs significantly changed at most time points. Interestingly, the plasma viral loads were negatively correlated with CD4 expression, but were positively correlated with CCR5 expression of pDCs. During this period, both CD1c(+) mDCs and pDCs were activated by enhancing expressions of co-stimulatory molecules, accompanied with increase in CCR7. Either CD80 or CD86 expressed on CD1c(+) mDCs and pDCs was positively correlated with the plasma viral loads. Our analysis demonstrates that the pDCs were more prone to apoptosis after infection during the acute phase of SIVmac239 infection, which may be due to their high expressions of CD4 and CCR5. Both DCs subsets activated through elevating the expression of co-stimulatory molecules, which was beneficial in controlling the replication of SIV. However, a mere broad immune activation initiated by activated DCs may lead to tragic AIDS progression.

Dendritic cell subsets dynamics and cytokine production in SIVmac239-infected Chinese rhesus macaques

Background

Several studies have demonstrated that SIV infection progresses more slowly to experimental AIDS in Chinese rhesus macaques (Ch Rhs) than in Indian rhesus macaques (Ind Rhs). Here we investigated the dynamic and functional changes in dendritic cell (DC) subsets in SIVmac239-infected Ch Rhs.

Results

The numbers of both mDC and pDC strongly fluctuated but were not significantly changed during the acute and chronic phases of infection. However, the concentration of both poly (I:C)-induced IL-12 and HSV-1-induced IFN-α significantly increased in the acute phase of infection but returned to normal levels at the chronic phase of infection. The peak of IFN-α emerged earlier than that of IL-12, and it had a significantly positive correlation with IL-12, which indicated that IFN-α may initiate the immune activation. We also found that only the concentration of IFN-α was positively correlated with CD4+ T-cell counts, but it was negatively correlated with viral load.

Conclusion

High levels of IFN-α in the early stage of infection may contribute to effective control of virus replication, and normal levels of IFN-α during chronic infection may help Ch Rhs resist the disease progression. The change in DC subsets dynamics and cytokine production may help further our understanding of why Ch Rhs are able to live longer without progressing to an AIDS-like illness.

Photochromism and two-photon luminescence of Ag-TiO(2) granular composite films activated by near infrared ps/fs pulses

We reported photochromism and largely enhanced visible two-photon luminescence (TPL) of Ag-TiO(2) granular composite films by using ps/fs laser at the wavelength of 800 nm. Three types of photochromism spectra were observed when the Ag atom fraction are less than, comparable to and larger than the percolation threshold. The strong surface-plasmon-resonance enhanced visible TPL emissions near Ag(2)O transition band from the photoactivated Ag-TiO(2) samples were also observed. Furthermore, we found that the TPL intensity saturatedly increased while the absorbance at 800 nm exponentially decreased with the same rate as the increasing of photoactivation time, which means that both photochromism and TPL of Ag-TiO(2) composite films are originated from the photo-oxidation of Ag to Ag(+). These observations exhibit the multifunctional features of Ag nanoparticle materials.

Modulation of natural killer cell activity affected by electroacupuncture through lateral hypothalamic area in rats

Electroacupuncture (EA) has been reported to modulate natural killer cell (NK cell) activities. Also it is well known that hypothalamus directly mediates the effects of EA on analgesia. Especially lateral hypothalamic area (LHA) is related to splenic NK cell activities. In order to investigate the relationship between hypothalamus and effects of EA on NK cell activity, lesions have been made bilaterally at LHA of Spraque-Dawley rats. Subsequently, NK cell cytotoxities of normal and lesioned rats were measured with (51)Cr release immunoassay after EA stimulation for 2 and 14 days. NK cell activity of EA group was significantly higher than sham group. In addition, lesions abolished effects of EA on NK cell activity. These results strongly suggest that LHA is closely related to increase of NK cell activity induced by EA.

Relationship between regional cardiac hyperinnervation and ventricular arrhythmia

BACKGROUND

Sympathetic nerve activity is known to be important in ventricular arrhythmogenesis, but there is little information on the relation between the distribution of cardiac sympathetic nerves and the occurrence of spontaneous ventricular arrhythmias in humans.

METHODS AND RESULTS

We studied 53 native hearts of transplant recipients, 5 hearts obtained at autopsy of patients who died of noncardiac causes, and 7 ventricular tissues that had been surgically resected from the origin of ventricular tachycardia. The history was reviewed to determine the presence (group 1A) or absence (group 1B) of spontaneous ventricular arrhythmias. Immunocytochemical staining for S100 protein, neurofilament protein, tyrosine hydroxylase, and protein gene product 9.5 was performed to study the distribution and the density of sympathetic nerves. The average left ventricular ejection fraction was 0.22+/-0.07. A total of 30 patients had documented ventricular arrhythmias, including ventricular tachycardia and sudden cardiac death. A regional increase in sympathetic nerves was observed around the diseased myocardium and blood vessels in all 30 hearts. The density of nerve fibers as determined morphometrically was significantly higher in group 1A patients (total nerve number 19.6+/-11.2/mm(2), total nerve length 3.3+/-3.0 mm/mm(2)) than in group 1B patients (total nerve number 13.5+/-6.1/mm(2), total nerve length 2.0+/-1.1 mm/mm(2), P<0. 05 and P<0.01, respectively).

CONCLUSIONS

There is an association between a history of spontaneous ventricular arrhythmia and an increased density of sympathetic nerves in patients with severe heart failure. These findings suggest that abnormally increased postinjury sympathetic nerve density may be in part responsible for the occurrence of ventricular arrhythmia and sudden cardiac death in these patients.