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1.
FASEB journal : official publication of the Federation of American Societies for Experimental Biology ; 36(Suppl 1), 2022.
Article in English | EuropePMC | ID: covidwho-1980839

ABSTRACT

Neuropathological complications are frequently observed in SARS‐CoV‐2 infection and brain autopsies from human subjects who died from COVID‐19 have revealed significant pathology, including wide‐spread neuroinflammation, hypoxic‐ischemic injury, and microhemorrhages. To begin to understand the neuropathogenesis of SARS‐CoV‐2 infection, we investigated brain from infected non‐human primates (NHP)s for pathological changes consistent with that seen among humans. Eight aged NHPs were inoculated with the 2019‐nCoV/USA‐WA1/2020 strain of SARS‐CoV‐2 via a multi‐route mucosal or aerosol challenge. Hematoxylin and eosin (H&E) and immunohistochemistry (IHC) staining was done on seven brain regions to elucidate general pathology, microhemorrhages, platelet derived thrombi, neuronal apoptosis, microglia and astrocyte morphology, hypoxia, and virus present. Similar to humans, pathology was variable but included wide‐spread neuroinflammation, nodular lesions, neuronal degeneration, and microhemorrhages. Neuronal degeneration was most often seen in the cerebellum and brainstem of infected animals. Neuronal death was confirmed through FluorJade C and cleaved (active) caspase 3 IHC, which showed foci of positivity, particularly among Purkinje cells of the cerebellum. Importantly, this was seen among infected animals that did not develop severe respiratory disease. Hypoxia inducible factor‐1α (HIF‐1α) was observed at a higher intensity around the vasculature within deep brain regions of the infected animals. Microhemorrhages were prevalent among all animals but were less frequently associated with platelet derived thrombi in the infected animals, as compared to mock‐infected controls. Sparse virus was detected in brain endothelial cells but did not associate with the severity of CNS injury. Increased HIF‐1α suggests that brain hypoxia may promote neuronal degeneration within infected brain. Wide‐spread neuroinflammation may also contribute to neuronal injury/death and neurological manifestations seen in the context of infection.

2.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-336004

ABSTRACT

SUMMARY SARS-CoV-2 infection causes a spectrum of clinical outcomes and diverse memory responses. Population studies indicate that viral neutralizing antibody responses are protective, but do not always develop post-infection. Other antiviral antibody effector functions, T-cell responses, or immunity to seasonal coronaviruses (OC43, 229E) have been implicated but not defined in all ages. Here, we identify that children and adult subjects generate polyfunctional antibodies to the spike protein after asymptomatic infection or mild disease, with some subjects developing cellular responses without seroconversion. Diversity in immunity was explained by two clusters distinguished by CD4+ T-cell cytokines, age, and antibodies to seasonal coronaviruses. Post-vaccination neutralizing responses were predicted by specific post-infection immune measures, including IL-2, spike-IgA, OC43-IgG1, 229E-IgM. We confirm a key role for CD4+ T cell cytokines in functionality of anti-spike antibodies, and show that antibody diversity is impacted by age, Th/Th2 cytokine biases, and antibody isotypes to SARS-CoV-2 and seasonal coronaviruses.

3.
Nat Commun ; 13(1): 1745, 2022 04 01.
Article in English | MEDLINE | ID: covidwho-1773978

ABSTRACT

Neurological manifestations are a significant complication of coronavirus disease (COVID-19), but underlying mechanisms aren't well understood. The development of animal models that recapitulate the neuropathological findings of autopsied brain tissue from patients who died from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are critical for elucidating the neuropathogenesis of infection and disease. Here, we show neuroinflammation, microhemorrhages, brain hypoxia, and neuropathology that is consistent with hypoxic-ischemic injury in SARS-CoV-2 infected non-human primates (NHPs), including evidence of neuron degeneration and apoptosis. Importantly, this is seen among infected animals that do not develop severe respiratory disease, which may provide insight into neurological symptoms associated with "long COVID". Sparse virus is detected in brain endothelial cells but does not associate with the severity of central nervous system (CNS) injury. We anticipate our findings will advance our current understanding of the neuropathogenesis of SARS-CoV-2 infection and demonstrate SARS-CoV-2 infected NHPs are a highly relevant animal model for investigating COVID-19 neuropathogenesis among human subjects.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Brain , Endothelial Cells , Humans , Primates
4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-325034

ABSTRACT

Background: A large-scale global outbreak of coronavirus disease-19 (COVID-19) out of Wuhan, from China, occurred in January 2020. Objective: To examine the clinical characteristics of COVID-19in infected patients out of Wuhan, from China. Patients and Methods: Thirteen patients were confirmed to be infected with novel coronavirus-2019 (2019-nCoV) between January 27andFebruary 8, 2020, in Baoji city, Shanxi, northwestern China. Epidemiological and clinical information, and computed to morphology imaging data from all COVID-19 patients were collected;cases were divided into two groups according to the severity of infection (mild or severe). Results: : Nine (9/13) COVID-19patientsexhibitedmild disease severity, and defined as second-generation, human-to-human transmission cases. Most patients (11/13) had a history of travel to or from Wuhan. There were no differences in sex and age between the mild and severe cases (all P >0.05). A moderate degree of fever (11/13), cough (13/13), and fatigue (8/13) were common symptoms;however, there was no statistical difference between mild and severe cases in this regard (all P >0.05). Oxyhemoglobin saturation and oxygenation index decreased, and C-reactive protein (CRP) and serum amyloid A (SAA) levels were elevated in all patients with COVID-19infection, with statistically significant differences between those with severe disease and mild infection (all P <0.05).Twelve of 13COVID-19patients exhibited changes in chest CT imaging features, and time course changes were different between mild and severe cases (all P <0.05). Conclusion: Most cases of COVID-19infection were second-generation human-to-human transmissions from Wuhan and were mild in severity. The clinical characteristics of COVID-19varied.Oxyhemoglobin saturation, oxygenation index, CRP and SAA levels, and CT features were reliable parameters to evaluate the severity of COVID-19 infection. However, a few patients with mild COVID-19diseaselackedtypicalcharacteristics such as fever and changes in CT imaging features.

5.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-310503

ABSTRACT

Neurological manifestations are a significant complication of coronavirus infection disease-19 (COVID-19). Understanding how COVID-19 contributes to neurological disease is needed for appropriate treatment of infected patients, as well as in initiating relevant follow-up care after recovery. Investigation of autopsied brain tissue has been key to advancing our understanding of the neuropathogenesis of a large number of infectious and non-infectious diseases affecting the central nervous system (CNS). Due to the highly infectious nature of the etiologic agent of COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is a paucity of tissues available for comprehensive investigation. Here, we show for the first time, microhemorrhages and neuropathology that is consistent with hypoxic injury in SARS-CoV-2 infected non-human primates (NHPs). Importantly, this was seen among infected animals that did not develop severe respiratory disease. This finding underscores the importance of vaccinating against SARS-CoV-2, even among populations that have a reduced risk for developing of severe disease, to prevent long-term or permanent neurological sequelae. Sparse virus was detected in brain endothelial cells but did not associate with the severity of CNS injury. We anticipate our findings will advance our current understanding of the neuropathogenesis of SARS-CoV-2 infection and demonstrate SARS-CoV-2 infected NHPs are a highly relevant animal model for investigating COVID-19 neuropathogenesis among human subjects.

6.
Cell Rep Methods ; 2(2): 100173, 2022 Feb 28.
Article in English | MEDLINE | ID: covidwho-1670392

ABSTRACT

SARS-CoV-2 variants of concern (VOCs) that increase transmission or disease severity or reduce diagnostic or vaccine efficacy continue to emerge across the world. Current methods available to rapidly detect these can be resource intensive and thus sub-optimal for large-scale deployment needed during a pandemic response. Here, we describe a CRISPR-based assay that detects mutations in spike gene CRISPR PAM motif or seed regions to identify a pan-specific VOC single-nucleotide polymorphism (SNP)) ((D614G) and Alpha- and Delta-specific (S982A and D950N) SNPs. This assay exhibits good diagnostic sensitivity and strain specificity with nasal swabs and is designed for use in laboratory and point-of-care settings. This should enable rapid, high-throughput VOC identification required for surveillance and characterization efforts to inform clinical and public health decisions. Furthermore, the assay can be adapted to target similar SNPs associated with emerging SARS-CoV-2 VOCs, or other rapidly evolving viruses.

7.
Emerg Microbes Infect ; 11(1): 629-638, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1665837

ABSTRACT

Mounting evidence indicates that SARS-CoV-2 can infect multiple systemic tissues, but few studies have evaluated SARS-CoV-2 RNA dynamics in multiple specimen types due to their reduced accessibility and diminished performance of RT-qPCR with non-respiratory specimens. Here, we employed an ultrasensitive CRISPR-RT-PCR assay to analyze longitudinal mucosal (nasal, buccal, pharyngeal, and rectal), plasma, and breath samples from SARS-CoV-2-infected non-human primates (NHPs) to detect dynamic changes in SARS-CoV-2 RNA level and distribution among these specimens. We observed that CRISPR-RT-PCR results consistently detected SARS-CoV-2 RNA in all sample types at most time points post-infection, and that SARS-CoV-2 infection dose and administration route did not markedly affect the CRISPR-RT-PCR signal detected in most specimen types. However, consistent RT-qPCR positive results were restricted to nasal, pharyngeal, and rectal swab samples, and tended to decrease earlier than CRISPR-RT-PCR results, reflecting lower assay sensitivity. SARS-CoV-2 RNA was detectable in both pulmonary and extrapulmonary specimens from early to late infection by CRISPR-RT-PCR, albeit with different abundance and kinetics, with SARS-CoV-2 RNA increases detected in plasma and rectal samples trailing those detected in upper respiratory tract samples. CRISPR-RT-PCR assays for SARS-CoV-2 RNA in non-respiratory specimens may thus permit direct diagnosis of suspected COVID-19 cases missed by RT-PCR, while tracking SARS-CoV-2 RNA in minimally invasive alternate specimens may better evaluate the progression and resolution of SARS-CoV-2 infections.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Humans , Primates , RNA, Viral/analysis , Sensitivity and Specificity , Serologic Tests
8.
Front Oncol ; 11: 719554, 2021.
Article in English | MEDLINE | ID: covidwho-1533689

ABSTRACT

Peritoneal lymphomatosis is extremely rare and associated with poor prognosis. Most practitioners only pay more attention to peritoneal carcinomatosis. However, peritoneal lymphomatosis can be neglected and misdiagnosed. We report a teenager with 10 days of abdominal distension and pain accompanied by computed tomography scan suggesting diffuse thickening of the peritoneum and omentum and abdominopelvic effusion. Tuberculous peritonitis and peritoneal carcinomatosis were initially suspected. However, it was finally confirmed as non-Hodgkin's B-cell lymphoma by omentum biopsies. He achieved complete remission after chemotherapy and autologous stem cell transplantation. But unfortunately, he suffered a relapse and died 10 months after diagnosis. Following a review of the literature, it can be concluded that the discovery of lymphomatosis in peritoneum is a rare finding. Lymphoma should be considered in the differential diagnosis of unexplained peritoneal thickening on computed tomography, and this case emphasizes the importance of early pathological diagnosis to make sure that the right treatment can be started opportunely.

9.
Blood ; 136(Supplement 1):40-41, 2020.
Article in English | PMC | ID: covidwho-1339040

ABSTRACT

IntroductionIn the absence of effective and readily available therapy for COVID-19, immediate interventions to improve its mortality are a public health emergency. COVID-19 convalescent plasma (CCP) carries antibodies against SARS-CoV-2 and represents a promising approach. Studies regarding the clinical use of CCP have been inconsistent, and the optimal timing and frequency of CCP infusion remain largely unknown. Similarly, the role of CCP in cancer patients, particularly those with hematological malignancies (HM), remains unknown. Herein we describe the outcomes of 16 critically ill patients with COVID-19, including HM, who were treated with CCP with marked clinical improvement.MethodsCCP donors donated 2-4 units each (200 ml per unit), 18 to 56 days following full recovery from COVID-19. 16 patients received CCP following informed consent. 5 patients were treated after obtaining individual emergency Investigational New Drug (eIND) from the FDA, while the remaining 11 patients were enrolled in our investigator-initiated clinical trial, Expanded Access to Convalescent Plasma to Treat and Prevent Pulmonary Complications Associated With COVID-19 (clinicaltrials.gov Identifier: NCT04358211). We used ELISA to determine the Spike protein IgG titers on most CCP units. Treatment was with a single unit of 200ml of CCP given over 1h, with the exception of patients 4 and 9 who received two units eight days apart.Results10 males and 6 females between the ages of 24-81 were treated, 6 of which with HM. 12 patients were diagnosed by an RT-PCR-based technique while 4 were diagnosed by the highly sensitive clustered regularly interspaced short palindromic repeats (CRISPR)-based qualitative COVID-19 assay. Interestingly, these 4 patients have HM and had multiple false negative RT-PCR results prior to the CRISPR diagnosis. The Spike protein IgG titers on CCP units used to treat patient-5, patient-6, patient-8, patient-9, patient-11, patient-13, patient-14, patient-15, and patient-16 were 1:1600, 1:3200, 1:3200, 1:800, 1:400, 1:1600, 1:3200, 1:6400, and 1:3200, respectively. At the time of CCP infusion, patients were either mechanically ventilated (5), on noninvasive support with high flow nasal cannula (4), bilevel ventilation (1), or nasal cannula (5). Only 1 patient was on room air at the time of CCP infusion. No adverse events were reported in all patients with the exception of a fever during CCP transfusion in patient-10 resulting in infusion of only 100 ml. Steady improvement in oxygenation levels was observed following each CCP infusion. All of the 5 intubated patients were extubated between 1- and 19-days post CCP infusion. The remaining 11 showed a dramatic decline in oxygen needs and did not require ventilatory support. Of the 16 patients included here, only 1 patient expired following extubation secondary to progression of medical co-morbidities and the family's decision to transition to comfort care. Among the 15 patients surviving, patient-12 remains inpatient for respiratory failure following extubation to tracheostomy, while the rest were successfully discharged including the 6 patients with HM (Figure 1). Although all of our patients showed improvement following CCP, we noted a strong correlation between early CCP infusion and clinical improvement (r=0.6, p=0.02, for correlation between time from disease onset to CCP, and time from CCP to oxygen independence or discharge).Interpretation of the data could potentially be affected by the concomitant clinical trial enrollment of some patients. Patients 14, and 15 were enrolled in ACTT-1, a randomized, double-blind, placebo-controlled trial to evaluate the safety and efficacy of remdesivir in hospitalized adults diagnosed with COVID-19 (ClinicalTrials.gov Identifier: NCT04280705);patients 3, 15, and 16, were enrolled in REGN88, a randomized, double-blind, placebo-controlled trial to evaluate the safety and efficacy of sarilumab in hospitalized adults diagnosed with COVID-19 (ClinicalTrials.gov Identifier: NCT04327388), while patients 1, 2, 5 and 6 received remdesivir out ide of a clinical trial context, and patients 5, 6, 7, 8 ,12, and 15 received dexamethasone.ConclusionWhile a randomized controlled clinical trial remains the gold standard, our limited data represent a signal that CCP is safe and efficacious in COVID-19 and underscores a potential role for passive immunity in this disease.

10.
Blood ; 136(Supplement 1):6-7, 2020.
Article in English | PMC | ID: covidwho-1338986

ABSTRACT

IntroductionPatients with hematological malignancies (HM) are uniquely immunocompromised and considered at high risk for COVID-19. However, data regarding the diagnosis, clinical course, treatment, and outcomes of these patients is sparse. In particular, the ability to successfully detect SARS-CoV-2 in patients with HM remains unknown. We have previously reported 2 cases of allogeneic stem cell transplant (SCT) diagnosed with COVID-19 using clustered regularly interspaced short palindromic repeats (CRISPR) technique, following multiple negative nasopharyngeal RT-PCR testing (Niu et al. Bone Marrow Transplantation - Nature). Here we examine 29 patients with a variety of HM with high suspicion for COVID-19 based on clinical presentation, lab results, and imaging, whom were tested with CRISPR and/or RT-PCR based techniques. From 3/31/20 to 7/17/20, 29 patients (age 24 to 82) with a variety of HM (20 lymphoid, 9 myeloid;Table 1), 24 of which presented with an undiagnosed respiratory illness and 5 presented while asymptomatic for testing prior to chemotherapy, were evaluated for COVID-19. While 16 patients tested positive for COVID-19 with guideline-directed nasopharyngeal RT-PCR testing (including the 5 asymptomatic patients), 13 patients tested negative with the same technique. However, based on their clinical history, imaging, and disease course, concern for COVID-19 infection remained in these 13 patients. We then used CRISPR technology available at our institution (Huang et al. Biosensors and Bioelectronics) to test 8 patients who initially tested negative by RT-PCR. Surprisingly, 7 of the 8 patients tested positive for COVID-19 with either a blood sample and/or nasal swab for the SARS-CoV-2 specific N gene and ORF1ab gene. Excluding the patients who were negative by RT-PCR and not tested by CRISPR, the rate of false negativity with RT-PCR testing is significantly elevated at 29% (7/24) in our cohort of HM, which compares unfavorably with the expected false negative rates of RT-PCR techniques.A very high fatality rate was observed with 9 out of the 29 patients (31%) ultimately dying. Fifteen patients were undergoing active chemotherapy, 4 had received an autologous SCT, 6 had received an allogeneic SCT, and 4 were on surveillance. Of the 23 COVID-19 positive patients (by RT-PCR or CRISPR), 8 patients received COVID-19-directed therapy with either hydroxychloroquine/azithromycin, remdesivir, and/or Covid-19 convalescent plasma (CCP) depending on their clinical status, and 4 patients expired. Of the 8 treated patients, 7 improved while 1 patient expired. For the 5 patients who were negative for RT-PCR with no CRISPR completed, 1 patient received hydroxychloroquine/azithromycin proactively due to symptoms and imaging and recovered, while 3 patients expired at outside facilities due to unknown causes. Breakdown of testing and treatment is shown in Fig. 1.The majority of our patients had undergone SCT or were actively on chemotherapy, notably lymphodepleting chemotherapy. Associated with the fact that COVID-19 is known to worsen lymphopenia, our patient's symptoms and immune response to COVID-19 is likely to differ from immunocompetent hosts. This translated into an overall worse outcome as seen by the high mortality with our patients. In our limited dataset, patients presented with a variety of symptoms ranging from asymptomatic to acute respiratory failure. Intriguingly, the 5 asymptomatic patients had lymphoid malignancies and were on chemotherapy.It is thus imperative to establish the diagnosis of COVID-19 quickly, as faster initiation of treatment has been associated with better outcomes. The 8 patients who were diagnosed and treated improved substantially. However, as seen by our dataset, a strikingly high false negative rate was observed. Thus, a high clinical suspicion must guide further workup and therapy in patients with HM who present with an undiagnosed respiratory illness consistent with COVID-19. Patients with HM can have a wide variety of presentations when infected with COVID-19. For this select patient population we must establish an algorithm to diagnose COVID-19 efficiently as we reported a high number of initial false negative COVID-19 tests before the more sensitive CRISPR revealed a positive test. In addition, treatment pathways need to be instituted to not only treat COVID-19 infection, but also provide the best treatment for these patient's underlying HM.

11.
Nat Nanotechnol ; 16(9): 1039-1044, 2021 09.
Article in English | MEDLINE | ID: covidwho-1322483

ABSTRACT

Plasma SARS-CoV-2 RNA may represent a viable diagnostic alternative to respiratory RNA levels, which rapidly decline after infection. Quantitative PCR with reverse transcription (RT-qPCR) reference assays exhibit poor performance with plasma, probably reflecting the dilution and degradation of viral RNA released into the circulation, but these issues could be addressed by analysing viral RNA packaged into extracellular vesicles. Here we describe an assay approach in which extracellular vesicles directly captured from plasma are fused with reagent-loaded liposomes to sensitively amplify and detect a SARS-CoV-2 gene target. This approach accurately identified patients with COVID-19, including challenging cases missed by RT-qPCR. SARS-CoV-2-positive extracellular vesicles were detected at day 1 post-infection, and plateaued from day 6 to the day 28 endpoint in a non-human primate model, while signal durations for 20-60 days were observed in young children. This nanotechnology approach uses a non-infectious sample and extends virus detection windows, offering a tool to support COVID-19 diagnosis in patients without SARS-CoV-2 RNA detectable in the respiratory tract.


Subject(s)
COVID-19/diagnosis , Extracellular Vesicles/metabolism , Liposomes/therapeutic use , RNA, Viral/blood , SARS-CoV-2/isolation & purification , Animals , Biosensing Techniques , COVID-19/blood , COVID-19 Nucleic Acid Testing , Chlorocebus aethiops , Disease Models, Animal , HEK293 Cells , Humans , Kinetics , Liposomes/metabolism , RNA, Viral/genetics , SARS-CoV-2/genetics , Tetraspanin 28/immunology , Tetraspanin 28/metabolism
12.
World J. Pediatric Surg. ; 1(3)20200423.
Article in English | WHO COVID, ELSEVIER | ID: covidwho-1318222

ABSTRACT

The outbreak of Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged and spread rapidly throughout the world. As of February 29, 2020, 79 389 cases of COVID-19 have been reported, and the outbreak is linked to 2838 deaths. The population is generally susceptible to the disease, and differences in incubation periods after infection exist among individuals. These two aspects of COVID-19 pose significant challenges to pediatric orthopedic diagnosis and treatment. As a dedicated center for managing pediatric cases of SARS-CoV-2 in Shanghai, our hospital has mobilized all branches and departments to undertake joint actions for scientific prevention and control, precise countermeasure and comprehensive anti-epidemic efforts. Combined with our experience, we have consulted the relevant national regulations and the latest research advances and have formulated the prevention and control measures of SARS-CoV-2 infection, including outpatient, emergency, inpatient and surgical cares, for clinical practices of pediatric orthopedics according to the physicochemical properties of SARS-CoV-2. It may serve as practical references and recommendations for managing SARS-CoV-2 infection in other pediatric specialties and in other hospitals.

13.
The FASEB Journal ; 35(S1), 2021.
Article in English | Wiley | ID: covidwho-1233967

ABSTRACT

SARS-CoV-2 infection impacts multiple organ systems, including the central nervous system (CNS). Multiple reports have described a variety of neurological manifestations associated with infection that may contribute to worsening COVID-19. The neuropathology of SARS-CoV-2 is not well understood, necessitating the development of relevant animal models for investigation. Here, we report marked neuropathology but with limited virus in the CNS of two non-human primate models (NHPs) of SARS-CoV-2 infection. Adult male and female purpose-bred Rhesus macaques (RMs;n = 4) and wild-caught African green monkeys (AGMs;n = 4) were inoculated with the 2019-nCoV/USA-WA1/2020 strain of SARS-CoV-2 via multi-route mucosal or aerosol challenge. SARS-CoV-2 nucleocapsid (SARS-N) mRNA was detected in nasal swabs within the first week of inoculation, demonstrating infection of all study animals. All animals were euthanized at the study endpoint of 4 weeks post-inoculation, with the exception of two AGMs that reached humane endpoints at 8- and 22-days post-challenge. Seven regions of the CNS were investigated for pathology and virus infection. Archival brain tissues from two non-infected adult female RMs were used as aged-matched controls. Mild, but chronic, hypoxemia with impaired gas exchange were suggested by SpO2 values that stayed at or below 95% and elevated blood CO2 in the majority of the study animals. Neuroinflammation was seen throughout the brain and brainstem but with limited virus detection by immunohistochemistry and RNAscope of fixed tissues and viral RNA detection using a highly sensitive CRISPR-fluorescent detection system on RNA extracted from sectioned brain lysates. In addition, neuronal injury and death were suggested by pyknotic and karyolytic nuclei and cellular blebbing. Limited myelin vacuolation was revealed in two infected animals through Luxol Fast Blue staining. Neuronal cleaved caspase 3 positivity was seen at a greater frequency in infected animals compared to controls, suggesting increased apoptosis in infection. Microhemorrhages were larger and more frequent among infected NHPs, as compared to controls. Neuroinflammation, neuronal injury and death, and microhemorrhages were seen in animals that did not develop severe respiratory disease and may suggest neuropathology contributes to on-going symptoms of convalesced patients. Our findings in NHPs are in agreement with human autopsy and neuroimaging studies and demonstrate this is a relevant animal model for investigating neuropathological changes associated with COVID-19. Our results also suggest that hypoxic-ischemic events leading to energy failure and neuronal injury, contribute to the neuropathological consequences of COVID-19. Further studies are warranted to elucidate the mechanisms of SARS-CoV-2 neuropathogenesis.

14.
Preprint in English | medRxiv | ID: ppmedrxiv-21257164

ABSTRACT

The emergence of the novel coronavirus pneumonia (Covid-19) pandemic at the end of 2019 led to chaos worldwide. The world breathed a sigh of relief when some countries announced that they had obtained the appropriate vaccine and gradually began to distribute it. Nevertheless, the emergence of another wave of this disease has returned us to the starting point. At present, early detection of infected cases has been the paramount concern of both specialists and health researchers. This paper aims to detect infected patients through chest x-ray images. The large dataset available online for Covid-19 (COVIDx) was used in this research. The dataset consists of 2,128 x-ray images of Covid-19 cases, 8,066 normal cases, and 5,575 cases of pneumonia. A hybrid algorithm was applied to improve image quality before conducting the neural network training process. This algorithm consisted of combining two different noise reduction filters in the images, followed by a contrast enhancement algorithm. In this paper, for Covid-19 detection, a novel convolution neural network (CNN) architecture, KL-MOB (Covid-19 detection network based on MobileNet structure), was proposed. KL-MOB performance was boosted by adding the Kullback-Leibler (KL) divergence loss function at the end when trained from scratch. The Kullback-Leibler (KL) divergence loss function was adopted as content-based image retrieval and fine-grained classification to improve the quality of image representation. This paper yielded impressive results, overall benchmark accuracy, sensitivity, specificity, and precision of 98.7%, 98.32%, 98.82%, and 98.37%, respectively. The promising results in this research may enable other researchers to develop modern and innovative methods to aid specialists. The tremendous potential of the method proposed in this research can also be utilized to detect Covid-19 quickly and safely in patients throughout the world.

16.
BMC Infect Dis ; 21(1): 207, 2021 Feb 24.
Article in English | MEDLINE | ID: covidwho-1102332

ABSTRACT

BACKGROUND: A large-scale global outbreak of coronavirus disease-19 (COVID-19) out of Wuhan, from China, occurred in January 2020. To examine the clinical characteristics of COVID-19 in infected patients out of Wuhan, from China. METHODS: Thirteen patients were confirmed to be infected with novel coronavirus-2019 (2019-nCoV) between January 27 and February 8, 2020, in Baoji city, Shannxi, northwestern China. Epidemiological and clinical information, and computed to morphology imaging data from all COVID-19 patients were collected; cases were divided into two groups according to the severity of infection (mild or severe). RESULTS: Nine (9/13) COVID-19 patients exhibited mild disease severity, and defined as second-generation human-to-human transmission cases. Most patients (11/13) had a history of travel to or from Wuhan. There were no differences in sex and age between the mild and severe cases (all P > 0.05). A moderate degree of fever (11/13), cough (13/13), and fatigue (8/13) were common symptoms; however, there was no statistical difference between mild and severe cases in this regard (all P > 0.05). Oxyhemoglobin saturation and oxygenation index decreased, and C-reactive protein (CRP) and serum amyloid A (SAA) levels were elevated in all patients with COVID-19 infection, with statistically significant differences between those with severe disease and mild infection (all P < 0.05). Twelve of 13 COVID-19 patients exhibited changes in chest CT imaging features, and time course changes were different between mild and severe cases (all P < 0.05). CONCLUSION: Most cases of COVID-19 infection were second-generation human-to-human transmissions from Wuhan and were mild in severity. The clinical characteristics of COVID-19 varied. Oxyhemoglobin saturation, oxygenation index, CRP and SAA levels, and CT features were reliable parameters to evaluate the severity of COVID-19 infection. However, a few patients with mild COVID-19 disease lacked typical characteristics such as fever and changes in CT imaging features.


Subject(s)
COVID-19/complications , SARS-CoV-2 , Adult , Aged , C-Reactive Protein/analysis , COVID-19/blood , COVID-19/epidemiology , Case-Control Studies , China/epidemiology , Female , Humans , Male , Middle Aged , Serum Amyloid A Protein/analysis , Tomography, X-Ray Computed
17.
J Clin Invest ; 131(7)2021 04 01.
Article in English | MEDLINE | ID: covidwho-1076050

ABSTRACT

BACKGROUNDCirculating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA may represent a more reliable indicator of infection than nasal RNA, but quantitative reverse transcription PCR (RT-qPCR) lacks diagnostic sensitivity for blood samples.METHODSA CRISPR-augmented RT-PCR assay that sensitively detects SARS-CoV-2 RNA was employed to analyze viral RNA kinetics in longitudinal plasma samples from nonhuman primates (NHPs) after virus exposure; to evaluate the utility of blood SARS-CoV-2 RNA detection for coronavirus disease 2019 (COVID-19) diagnosis in adults cases confirmed by nasal/nasopharyngeal swab RT-PCR results; and to identify suspected COVID-19 cases in pediatric and at-risk adult populations with negative nasal swab RT-qPCR results. All blood samples were analyzed by RT-qPCR to allow direct comparisons.RESULTSCRISPR-augmented RT-PCR consistently detected SARS-CoV-2 RNA in the plasma of experimentally infected NHPs from 1 to 28 days after infection, and these increases preceded and correlated with rectal swab viral RNA increases. In a patient cohort (n = 159), this blood-based assay demonstrated 91.2% diagnostic sensitivity and 99.2% diagnostic specificity versus a comparator RT-qPCR nasal/nasopharyngeal test, whereas RT-qPCR exhibited 44.1% diagnostic sensitivity and 100% specificity for the same blood samples. This CRISPR-augmented RT-PCR assay also accurately identified patients with COVID-19 using one or more negative nasal swab RT-qPCR results.CONCLUSIONResults of this study indicate that sensitive detection of SARS-CoV-2 RNA in blood by CRISPR-augmented RT-PCR permits accurate COVID-19 diagnosis, and can detect COVID-19 cases with transient or negative nasal swab RT-qPCR results, suggesting that this approach could improve COVID-19 diagnosis and the evaluation of SARS-CoV-2 infection clearance, and predict the severity of infection.TRIAL REGISTRATIONClinicalTrials.gov. NCT04358211.FUNDINGDepartment of Defense, National Institute of Allergy and Infectious Diseases, National Institute of Child Health and Human Development, and the National Center for Research Resources.


Subject(s)
COVID-19/blood , COVID-19/virology , Cell-Free Nucleic Acids/blood , Cell-Free Nucleic Acids/genetics , RNA, Viral/blood , RNA, Viral/genetics , SARS-CoV-2 , Adolescent , Adult , Aged , Animals , COVID-19/diagnosis , COVID-19 Nucleic Acid Testing/methods , COVID-19 Nucleic Acid Testing/statistics & numerical data , CRISPR-Cas Systems , Child , Child, Preschool , Disease Models, Animal , Female , Humans , Infant , Longitudinal Studies , Macaca mulatta , Male , Middle Aged , Pandemics , SARS-CoV-2/genetics , Sensitivity and Specificity , Time Factors
18.
Sci Adv ; 7(2)2021 01.
Article in English | MEDLINE | ID: covidwho-1066788

ABSTRACT

Point-of-care COVID-19 assays that are more sensitive than the current RT-PCR (reverse transcription polymerase chain reaction) gold standard assay are needed to improve disease control efforts. We describe the development of a portable, ultrasensitive saliva-based COVID-19 assay with a 15-min sample-to-answer time that does not require RNA isolation or laboratory equipment. This assay uses CRISPR-Cas12a activity to enhance viral amplicon signal, which is stimulated by the laser diode of a smartphone-based fluorescence microscope device. This device robustly quantified viral load over a broad linear range (1 to 105 copies/µl) and exhibited a limit of detection (0.38 copies/µl) below that of the RT-PCR reference assay. CRISPR-read SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) RNA levels were similar in patient saliva and nasal swabs, and viral loads measured by RT-PCR and the smartphone-read CRISPR assay demonstrated good correlation, supporting the potential use of this portable assay for saliva-based point-of-care COVID-19 diagnosis.


Subject(s)
COVID-19 Nucleic Acid Testing , COVID-19/diagnosis , Point-of-Care Testing , Saliva/virology , Smartphone , Animals , CRISPR-Cas Systems , Chlorocebus aethiops , Computer Simulation , Female , Humans , Limit of Detection , Macaca mulatta , Male , Molecular Diagnostic Techniques/instrumentation , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and Specificity , Vero Cells , Viral Load
20.
Front Immunol ; 11: 2033, 2020.
Article in English | MEDLINE | ID: covidwho-760861

ABSTRACT

Immune dysfunction and aberrant cytokine storms often lead to rapid exacerbation of the disease during late infection stages in SARS-CoV and MERS-CoV patients. However, the underlying immunopathology mechanisms are not fully understood, and there has been little progress in research regarding the development of vaccines, anti-viral drugs, and immunotherapy. The newly discovered SARS-CoV-2 (2019-nCoV) is responsible for the third coronavirus pandemic in the human population, and this virus exhibits enhanced pathogenicity and transmissibility. SARS-CoV-2 is highly genetically homologous to SARS-CoV, and infection may result in a similar clinical disease (COVID-19). In this review, we provide detailed knowledge of the pathogenesis and immunological characteristics of SARS and MERS, and we present recent findings regarding the clinical features and potential immunopathogenesis of COVID-19. Host immunological characteristics of these three infections are summarised and compared. We aim to provide insights and scientific evidence regarding the pathogenesis of COVID-19 and therapeutic strategies targeting this disease.


Subject(s)
Betacoronavirus/immunology , Coronavirus Infections/pathology , Middle East Respiratory Syndrome Coronavirus/immunology , Pneumonia, Viral/pathology , SARS Virus/immunology , Severe Acute Respiratory Syndrome/immunology , COVID-19 , Coronavirus Infections/immunology , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/pathology , Humans , Pandemics , Pneumonia, Viral/immunology , SARS-CoV-2 , Severe Acute Respiratory Syndrome/pathology
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