A follow-up study on the recovery and reinfection of Omicron COVID-19 patients in Shanghai, China.

Limited follow-up data is available on the recovery of Omicron COVID-19 patients after acute illness. It is also critical to understand persistence of neutralizing antibody (NAb) and of T-cell mediated immunity and the role of hybrid immunity in preventing SARS-CoV-2 reinfection. This prospective cohort study included Omicron COVID-19 individuals from April to June 2022 in Shanghai, China, during a large epidemic caused by the Omicron BA.2 variant. A total of 8945 patients from three medical centres were included in the follow up programme from November 2022 to February 2023. Of 6412 individuals enrolled for the long COVID analysis, 605 (9.4%) individuals experienced at least one sequelae, mainly had fatigue and mental symptoms specific to Omicron BA.2 infection compared with other common respiratory tract infections. During the second-visit, 548 (12.1%) cases of Omicron reinfection were identified. Hybrid immunity with full and booster vaccination had reduced risk of SARS-CoV-2 reinfection by 0.29-fold (95% CI: 0.63-0.81) and 0.23-fold (95% CI: 0.68-0.87), respectively. For 469 participants willing to the hospital during the first visit, those who received full (72 [IQR, 36-156]) or booster (64 [IQR, 28-132]) vaccination had significantly higher neutralizing antibody titers than those with incomplete vaccination (36 [IQR, 16-79]). Moreover, non-reinfection cases had higher neutralizing antibody titers (64 [IQR, 28-152]) compared to reinfection cases (32 [IQR, 20-69]).

Is coronal imbalance in degenerative lumbar scoliosis patients associated with the number of degenerated discs? A retrospective imaging cross-sectional study.

BACKGROUND: Degenerative lumbar scoliosis (DLS) is a common degenerative disease of the spine, that predominates in the elderly, and causes spinal deformities along with severe pain and reduced quality of life. The relationship between DLS and degenerated discs is now a new direction of research. Our study aimed to the relationship between the imaging parameters of coronal imbalance and the number of degenerated discs in patients with degenerative lumbar scoliosis and analyzed the segmental distribution of the degenerated discs in patients with DLS. METHODS: We performed a retrospective analysis of the imaging of 40 patients who met the inclusion criteria who attended our outpatient clinic between April 2021 and July 2021, measuring the intervertebral space height of the AV (high side and low side), Cobb angle, and AVT (Apical vertebral translation) from coronal X-ray. Degenerated discs were evaluated by the Pfirrmann score based on T2-weighted magnetic resonance images. We record the number of degenerated discs (Graded as Grade III, Grade IV or Grade V by the Pfirrmann score) and the segments in which they are located. Finally, we explore the relationship between the imaging parameters of coronal imbalance and the number of degenerated discs in patients with DLS. RESULT: Among the 40 patients with DLS in our study, all patients had degenerated discs in the lumbar spine, 95% of patients had degenerated discs(Pfirrmann score Grade III, Grade IV or Grade V) in 2 or more segments, with the L4-L5 segment being the most involved segment with the most degenerated discs, followed by the L3-L4 segment and the L5-S1 segment. There was no statistically significant relationship between the number of degenerated discs and the coronal imbalance in patients with DLS. CONCLUSION: Our results showed an association between DLS and degenerated discs, but there was no statistically significant relationship between imbalance in the coronal plane of the lumbar spine and the number of degenerated discs in patients with DLS. The distribution of degenerated disc segments in patients with DLS showed a higher likelihood of disc degeneration in 2 or more segments, and a higher frequency of disc degeneration in the inferior disc and in the adjacent segments of the AV.

Shufeng Jiedu capsules protect rats against LPS-induced acute lung injury via activating NRF2-associated antioxidant pathway.

Shufeng Jiedu capsule (SFJDC) is a traditional Chinese medicine, which has been used for the treatment of respiratory infections for more than thirty years in Hunan (China). SFJDC protected rats against LPS-induced acute lung injury (ALI); however, the molecular mechanisms underlying the therapeutic effects of SFJDC remain unclear. Therefore, this study aimed at analyzing the major anti-inflammatory compounds of SFJDC and exploring the underlying molecular mechanisms. SFJDC dissolved in water was fingerprinted by UPLC/Q-TOF. Inflammation response was assessed by histopathological examination and ELISA assay. Arterial blood gases were also analyzed to evaluate the function of rat lungs. The expression levels of Kelch-like ECH-associating protein 1 (Keap1), Nrf2, heme oxygenase-1 (HO1), Cullin 3 (CUL3) and NQO1 were analyzed by Western blotting. Results indicated that SFJDC alleviated inflammation response by reducing the level of inflammatory cytokines, and upregulation of glutathione-S-transferase (GST) and superoxide dismutase (SOD) in lung tissues. Furthermore, SFJDC suppressed LPS-induced upregulation of Keap 1 and CUL3 in rat lungs. The expression of NRF2 HO1 and NQO1 were further upregulated by SFJDC in the presence of LPS, indicating that SFJDC might activate the NRF2-associated antioxidant pathway. In conclusion, SFJDC treatment may protect the rat lungs from LPS by alleviating the inflammation response via NRF2-associated antioxidant pathway.

Axonotmesis-evoked plantar vasodilatation as a novel assessment of C-fiber afferent function after sciatic nerve injury in rats.

Quantitative assessment of the recovery of nerve function, especially sensory and autonomic nerve function, remains a challenge in the field of nerve regeneration research. We previously found that neural control of vasomotor activity could be potentially harnessed to evaluate nerve function. In the present study, five different models of left sciatic nerve injury in rats were established: nerve crush injury, nerve transection/suturing, nerve defect/autografting, nerve defect/conduit repair, and nerve defect/non-regeneration. Laser Doppler perfusion imaging was used to analyze blood perfusion of the hind feet. The toe pinch test and walking track analysis were used to assess sensory and motor functions of the rat hind limb, respectively. Transmission electron microscopy was used to observe the density of unmyelinated axons in the injured sciatic nerve. Our results showed that axonotmesis-evoked vasodilatation in the foot 6 months after nerve injury/repair recovered to normal levels in the nerve crush injury group and partially in the other three repair groups; whereas the nerve defect/non-regeneration group exhibited no recovery in vasodilatation. Furthermore, the recovery index of axonotmesis-evoked vasodilatation was positively correlated with toe pinch reflex scores and the density of unmyelinated nerve fibers in the regenerated nerve. As C-fiber afferents are predominantly responsible for dilatation of the superficial vasculature in the glabrous skin in rats, the present findings indicate that axonotmesis-evoked vasodilatation can be used as a novel way to assess C-afferent function recovery after peripheral nerve injury. This study was approved by the Ethics Committee for Laboratory Animals of Nantong University of China (approval No. 20130410-006) on April 10, 2013.

Neurological function following intra-neural injection of fluorescent neuronal tracers in rats.

Fluorescent neuronal tracers should not be toxic to the nervous system when used in long-term labeling. Previous studies have addressed tracer toxicity, but whether tracers injected into an intact nerve result in functional impairment remains to be elucidated. In the present study, we examined the functions of motor, sensory and autonomic nerves following the application of 5% Fluoro-Gold, 4% True Blue and 10% Fluoro-Ruby (5 µL) to rat tibial nerves via pressure injection. A set of evaluation methods including walking track analysis, plantar test and laser Doppler perfusion imaging was used to determine the action of the fluorescent neuronal tracers. Additionally, nerve pathology and ratio of muscle wet weight were also observed. Results showed that injection of Fluoro-Gold significantly resulted in loss of motor nerve function, lower plantar sensibility, increasing blood flow volume and higher neurogenic vasodilatation. Myelinated nerve fiber degeneration, unclear boundaries in nerve fibers and high retrograde labeling efficacy were observed in the Fluoro-Gold group. The True Blue group also showed obvious neurogenic vasodilatation, but less severe loss of motor function and degeneration, and fewer labeled motor neurons were found compared with the Fluoro-Gold group. No anomalies of motor and sensory nerve function and no myelinated nerve fiber degeneration were observed in the Fluoro-Ruby group. Experimental findings indicate that Fluoro-Gold tracing could lead to significant functional impairment of motor, sensory and autonomic nerves, while functional impairment was less severe following True Blue tracing. Fluoro-Ruby injection appears to have no effect on neurological function.

Laser doppler perfusion imaging of skin territory to reflect autonomic functional recovery following sciatic nerve autografting repair in rats.

Peripheral nerve repair requires comprehensive evaluation of functional outcomes of nerve regeneration; however, autonomic nerve function is seldom evaluated probably due to lack of suitable quantitative methods. This study sought to determine whether autonomic functional recovery could be reflected by cold-induced vasodilation (CIVD) within target skin territory, as monitored by laser Doppler perfusion imaging (LDPI). Rats with sciatic nerve defect injury received autologous nerve grafting, and the plantar surface of the hind feet was subjected to LDPI analysis following nerve repair. The results indicated that at 3 and 6 months after autologous nerve grafting, the plantar surface of the hind foot exhibited the same level of CIVD as contralateral normal side, whereas rats in nerve defect group (negative control) showed significantly reduced CIVD. In addition, suitable nerve regeneration and functional recovery were achieved as assessed by pain sensation tests as well as electrophysiological and immunohistological examinations. Based on the potential influence of local autonomic nerve signals on CIVD, it was possible to evaluate functional recovery of autonomic nerves by using LDPI measurements of dermal CIVD.