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1.
Virology ; 595: 110067, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38653156

RESUMO

Two SARS-CoV-2 XBB sub-variants, FL.1 and GE.1, have been increasing in prevalence worldwide, but limited information is available about their ability to evade the immune system. FL.1 and GE.1 are emerging Omicron XBB variants possessing additional mutations in the spike RBD raising concerns of increased neutralization escape. In this study, we assessed the neutralizing ability of eleven FDA-approved monoclonal antibody combinations against different Omicron variants, including BA.2.75, BA.2.76, BA.4/5, XBB.1.5, and CH.1.1. Among the eleven antibodies, Sotrovimab was the only antibody to show broad neutralization ability against XBB.1.5. However, Sotrovimab showed attenuated neutralization efficiency against recently emerging XBB sub-lineages EG.5, FL.1, and GE.1 compared to XBB.1.5. Additionally, XBB.1.5 seropositive convalescent sera displayed lower neutralization activity against EG.5, FL.1, and GE.1. Overall, our findings present enhanced immune evasion capacity of emerging XBB variants and emphasize the importance of continued monitoring of novel variants.

2.
Sci Rep ; 14(1): 7217, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538722

RESUMO

To evaluate the antibody response following the initial four doses of mRNA vaccines (BNT162b2 or mRNA-1273) in SARS-CoV-2-naïve healthy adults and investigate factors influencing antibody titer increases, this prospective cohort study was conducted in Japan from March 2021. The study included participants who received either the 1st and 2nd doses (n = 467), 3rd dose (n = 157), or 4th dose (n = 89). Blood samples were collected before and up to 6 months after each dose, and anti-receptor-binding domain antibody levels were measured. Multivariate analysis (usin multiple linear regression or linear mixed models) revealed several factors significantly associated with higher post-vaccination antibody levels, including mRNA-1273 vaccine (after the 1st and 2nd dose), male gender (after the 3rd and 4th doses), younger age (after the 1st and 2nd dose), non-smoking status (after the 2nd dose), non-use of immunosuppressive agents (after the 1st dose), higher pre-vaccination antibody titers (after the 2nd, 3rd, and 4th doses), and higher post-vaccination fever (after the 2nd and 4th doses). Furthermore, longer intervals since the last dose were significantly associated with higher antibody levels after the 3rd and 4th doses. These findings provide valuable insights for optimizing vaccination strategies.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , COVID-19 , Adulto , Masculino , Humanos , SARS-CoV-2 , Vacina BNT162 , Vacinas contra COVID-19 , Estudos Prospectivos , COVID-19/prevenção & controle , Anticorpos , Febre , RNA Mensageiro , Anticorpos Antivirais , Vacinação
3.
Malar J ; 23(1): 82, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500094

RESUMO

BACKGROUND: Adults infected with Plasmodium spp. in endemic areas need to be re-evaluated in light of global malaria elimination goals. They potentially undermine malaria interventions but remain an overlooked aspect of public health strategies. METHODS: This study aimed to estimate the prevalence of Plasmodium spp. infections, to identify underlying parasite species, and to assess predicting factors among adults residing in an endemic area from the Democratic Republic of Congo (DRC). A community-based cross-sectional survey in subjects aged 18 years and above was therefore carried out. Study participants were interviewed using a standard questionnaire and tested for Plasmodium spp. using a rapid diagnostic test and a nested polymerase chain reaction assay. Logistic regression models were fitted to assess the effect of potential predictive factors for infections with different Plasmodium spp. RESULTS: Overall, 420 adults with an estimated prevalence of Plasmodium spp. infections of 60.2% [95% CI 55.5; 64.8] were included. Non-falciparum species infected 26.2% [95% CI 22.2; 30.5] of the study population. Among infected participants, three parasite species were identified, including Plasmodium falciparum (88.5%), Plasmodium malariae (39.9%), and Plasmodium ovale (7.5%) but no Plasmodium vivax. Mixed species accounted for 42.3% of infections while single-species infections predominated with P. falciparum (56.5%) among infected participants. All infected participants were asymptomatic at the time of the survey. Adults belonging to the "most economically disadvantaged" households had increased risks of infections with any Plasmodium spp. (adjusted odds ratio, aOR = 2.87 [95% CI 1.66, 20.07]; p < 0.001), compared to those from the "less economically disadvantaged" households. Conversely, each 1 year increase in age reduced the risk of infections with any Plasmodium spp. (aOR = 0.99 [95% CI 0.97, 0.99]; p = 0.048). Specifically for non-falciparum spp., males had increased risks of infection than females (aOR = 1.83 [95% CI 1.13, 2.96]; p = 0.014). CONCLUSION: Adults infected with malaria constitute a potentially important latent reservoir for the transmission of the disease in the study setting. They should specifically be taken into account in public health measures and translational research.


Assuntos
Malária Falciparum , Malária , Masculino , Adulto , Feminino , Humanos , República Democrática do Congo/epidemiologia , Estudos Transversais , Malária/epidemiologia , Malária/parasitologia , Malária Falciparum/epidemiologia , Plasmodium falciparum , Plasmodium malariae , Prevalência
4.
J Gen Fam Med ; 25(1): 53-61, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38240001

RESUMO

Background: Coronavirus disease 2019 (COVID-19) sequelae, also known as long COVID, can present with various symptoms. Among these symptoms, autonomic dysregulation, particularly postural orthostatic tachycardia syndrome (POTS), should be evaluated. However, previous studies on the treatment of POTS complicated by COVID-19 are lacking. Therefore, this study aimed to investigate the treatment course of long COVID complicated by POTS. Methods: The medical records of patients who complained of fatigue and met the criteria for POTS diagnosis were reviewed. We evaluated the treatment days, methods and changes in fatigue score, changes in heart rate on the Schellong test, and social situation at the first and last visits. Results: Thirty-two patients with long COVID complicated by POTS were followed up (16 males; median age: 28 years). The follow-up period was 159 days, and the interval between COVID-19 onset and initial hospital attendance was 97 days. Some patients responded to ß-blocker therapy. Many patients had psychiatric symptoms that required psychiatric intervention and selective serotonin reuptake inhibitor prescription. Changes in heart rate, performance status, and employment/education status improved from the first to the last visit. These outcomes were believed to be because of the effects of various treatment interventions and spontaneous improvements. Conclusions: Our study suggests that the condition of 94% of patients with POTS complicated by long COVID will improve within 159 days. Therefore, POTS evaluation should be considered when patients with long COVID complain of fatigue, and attention should be paid to psychological symptoms and the social context.

5.
Trop Med Health ; 51(1): 68, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062533

RESUMO

BACKGROUND: Chagas disease can lead to life-threatening cardiac manifestations. Regional factors, including genetic characteristics of circulating Trypanosoma cruzi (T. cruzi), have attracted attention as likely determinants of Chagas disease phenotypic expression and Chagas cardiomyopathy (CCM) progression. Our objective was to elucidate the differential transcriptomic signatures of cardiomyocytes resulting from infection with genetically discrete T. cruzi strains and explore their relationships with CCM pathogenesis and progression. METHODS: HL-1 rodent cardiomyocytes were infected with T. cruzi trypomastigotes of the Colombian, Y, or Tulahuen strain. RNA was serially isolated post-infection for microarray analysis. Enrichment analyses of differentially expressed genes (fold-change ≥ 2 or ≤ 0.5) highlighted over-represented biological pathways. Intracellular levels of reactive oxygen species (ROS) were compared between T. cruzi-infected and non-infected HL-1 cardiomyocytes. RESULTS: We found that oxidative stress-related gene ontology terms (GO terms), 'Hypertrophy model', 'Apoptosis', and 'MAPK signaling' pathways (all with P < 0.01) were upregulated. 'Glutathione and one-carbon metabolism' pathway, and 'Cellular nitrogen compound metabolic process' GO term (all with P < 0.001) were upregulated exclusively in the cardiomyocytes infected with the Colombian/Y strains. Mean intracellular levels of ROS were significantly higher in the T. cruzi-infected cardiomyocytes compared to the non-infected (P < 0.0001). CONCLUSIONS: The upregulation of oxidative stress-related and hypertrophic pathways constitutes the universal hallmarks of the cardiomyocyte response elicited by T. cruzi infection. Nitrogen metabolism upregulation and glutathione metabolism imbalance may implicate a relationship between nitrosative stress and poor oxygen radicals scavenging in the unique pathophysiology of Chagas cardiomyopathy.

6.
Nat Commun ; 14(1): 8469, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123556

RESUMO

Effective early-stage markers for predicting which patients are at risk of developing SARS-CoV-2 infection have not been fully investigated. Here, we performed comprehensive serum metabolome analysis of a total of 83 patients from two cohorts to determine that the acceleration of amino acid catabolism within 5 days from disease onset correlated with future disease severity. Increased levels of de-aminated amino acid catabolites involved in the de novo nucleotide synthesis pathway were identified as early prognostic markers that correlated with the initial viral load. We further employed mice models of SARS-CoV2-MA10 and influenza infection to demonstrate that such de-amination of amino acids and de novo synthesis of nucleotides were associated with the abnormal proliferation of airway and vascular tissue cells in the lungs during the early stages of infection. Consequently, it can be concluded that lung parenchymal tissue remodeling in the early stages of respiratory viral infections induces systemic metabolic remodeling and that the associated key amino acid catabolites are valid predictors for excessive inflammatory response in later disease stages.


Assuntos
COVID-19 , Pneumonia , Humanos , Animais , Camundongos , SARS-CoV-2 , RNA Viral , Aminoácidos
7.
Trop Med Health ; 51(1): 64, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968745

RESUMO

CONTEXT: The Democratic Republic of Congo (DRC), one of the most malaria-affected countries worldwide, is a potential hub for global drug-resistant malaria. This study aimed at summarizing and mapping surveys of malaria parasites carrying molecular markers of drug-resistance across the country. METHODS: A systematic mapping review was carried out before July 2023 by searching for relevant articles through seven databases (PubMed, Embase, Scopus, African Journal Online, African Index Medicus, Bioline and Web of Science). RESULTS: We identified 1541 primary studies of which 29 fulfilled inclusion criteria and provided information related to 6385 Plasmodium falciparum clinical isolates (collected from 2000 to 2020). We noted the PfCRT K76T mutation encoding for chloroquine-resistance in median 32.1% [interquartile interval, IQR: 45.2] of analyzed malaria parasites. The proportion of parasites carrying this mutation decreased overtime, but wide geographic variations persisted. A single isolate had encoded the PfK13 R561H substitution that is invoked in artemisinin-resistance emergence in the Great Lakes region of Africa. Parasites carrying various mutations linked to resistance to the sulfadoxine-pyrimethamine combination were widespread and reflected a moderate resistance profile (PfDHPS A437G: 99.5% [IQR: 3.9]; PfDHPS K540E: 38.9% [IQR: 47.7]) with median 13.1% [IQR: 10.3] of them being quintuple IRN-GE mutants (i.e., parasites carrying the PfDHFR N51I-C59R-S108N and PfDHPS A437G-K540E mutations). These quintuple mutants tended to prevail in eastern regions of the country. Among circulating parasites, we did not record any parasites harboring mutations related to mefloquine-resistance, but we could suspect those with decreased susceptibility to quinine, amodiaquine, and lumefantrine based on corresponding molecular surrogates. CONCLUSIONS: Drug resistance poses a serious threat to existing malaria therapies and chemoprevention options in the DRC. This review provides a baseline for monitoring public health efforts as well as evidence for decision-making in support of national malaria policies and for implementing regionally tailored control measures across the country.

8.
Int J Parasitol Parasites Wildl ; 22: 167-174, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37876909

RESUMO

Japanese rock ptarmigans (Lagopus muta japonica) are birds that inhabit only alpine regions of central Honshu Island, Japan, known as the Japanese Alps. The number of these birds has recently declined, and in situ and ex situ national conservation programs for Japanese rock ptarmigans have been initiated. The infections of Eimeria spp. as protozoan parasites of the phylum Apicomplexa, E. uekii and E. raichoi, were frequently reported in the birds. However, the virulence of these Eimeria parasites has not been determined. Here, we analyzed the pathogenicity of these Eimeria parasites using experimental infections of a subspecies model of Japanese rock ptarmigans, Svalbard rock ptarmigans (Lagopus mutus hyperboreus), and evaluated acquired protective immunity against challenge in birds tolerant of low-dose inoculation with Eimeria parasites. Following inoculation with two Eimeria parasites derived from Japanese rock ptarmigans (dose range of 4 × 104 to 4 × 102 for E. uekii and 1.7 × 104 to 4 × 101 for E. raichoi), oocysts were detected at 6-8 days post-inoculation (PI), and the maximum number of oocysts per gram of feces was observed 7-10 days PI and then gradually decreased. The mortality rate and reduction in weight gain of chicks increased following high-dose inoculation of oocysts with abnormal feces (soft and diarrhea). Developmental zoites were detected histopathologically in epithelial tissues and sometimes the lamina propria from the duodenum to the colon. Chicks that survived low-dose inoculation did not show clear clinical symptoms after challenge inoculation. Our results suggest that the pathological characteristics of Eimeria parasites infecting Japanese rock ptarmigans include abnormal feces and reduction in weight gain, resulting in mortality in cases of heavy infection due to high-dose inoculation. These findings provide helpful data for Japanese rock ptarmigan conservation efforts.

9.
Vaccine ; 41(42): 6248-6254, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37673717

RESUMO

SARS-CoV-2 serological studies suggest that individual serum antibody repertoires can affect neutralisation breadth. Herein, we asked whether a BNT162b2 vaccine-induced epitope dominance pattern (i.e., predominant viral structural domain targeted by serum antibodies for virus neutralisation) affects cross-variant neutralisation. When a neutralisation assay against the ancestral strain was carried out using 16 vaccine sera preabsorbed with a recombinant receptor-binding domain (RBD) or an N-terminal domain (NTD) protein, three and 13 sera, respectively, showed lower neutralisation under NTD and RBD protein-preabsorbed conditions than under the other protein-preabsorbed conditions. This suggests that the NTD was responsible for virus neutralisation in three sera, whereas the other 13 sera elicited RBD-dominant neutralisation. The results also suggest the presence of infectivity-enhancing antibodies in four out of the 13 RBD-dominant sera. A neutralisation assay using SARS-CoV-2 variants revealed that NTD-dominant sera showed significantly reduced neutralising activity against the B.1.617.2 variant, whereas RBD-dominant sera retained neutralising activity even in the presence of infectivity-enhancing antibodies. Taken together, these results suggest the followings: (i) epitope dominance patterns are divided into at least two types: NTD-dominant and RBD-dominant; (ii) NTD-dominant sera have less potential to neutralise the B.1.617.2 variant than RBD-dominant sera; and (iii) infectivity-enhancing antibodies play a limited role in cross-variant neutralisation against the five variants tested.

10.
Parasitol Res ; 122(8): 1795-1800, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37264281

RESUMO

Eimeria spp. are protozoan parasites that are commonly found in a broad range of vertebrate hosts. These parasites generally exhibit strict host specificity, but some Eimeria spp. can infect groups of closely related species such as species within a genus or family. Compared with Eimeria spp. that infect livestock, limited information is available about such infections in wild animals including data on host specificity, virulence, and prevalence. The Japanese rock ptarmigan, Lagopus muta japonica, is an endangered bird belonging to the family Phasianidae, order Galliformes, and inhabits only alpine areas of Japan. In conservation efforts for these birds, two Eimeria spp., E. uekii and E. raichoi, were frequently detected. Here, we examined cross-transmission of the parasites to other bird species to characterize their infectivity as well as the development of experimental bird models to contribute to conservation programs by the oocyst transfer. Consequently, among the examined eight bird species (chickens, Japanese pheasants, turkeys, chukar partridges, quails, helmeted guineafowls and ducks), only turkeys (family Phasianidae, order Galliformes) could be infected with E. raichoi. However, the number of oocysts per feces was relatively low, and few parasites in the intestinal mucosa could be found by histopathological analyses. These results might indicate that E. uekii and E. raichoi are highly adapted to Japanese rock ptarmigans that inhabit the alpine zone although further studies are anticipated.


Assuntos
Animais Selvagens , Coccidiose , Eimeria , Espécies em Perigo de Extinção , Galliformes , Especificidade de Hospedeiro , Animais , Galinhas/parasitologia , Coccidiose/veterinária , Coccidiose/parasitologia , Galliformes/parasitologia , Oocistos , Codorniz/parasitologia , Japão , Fezes/parasitologia , Animais Selvagens/parasitologia , Patos/parasitologia
11.
Nat Commun ; 14(1): 2810, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208330

RESUMO

Several vaccines have been widely used to counteract the global pandemic caused by SARS-CoV-2. However, due to the rapid emergence of SARS-CoV-2 variants of concern (VOCs), further development of vaccines that confer broad and longer-lasting protection against emerging VOCs are needed. Here, we report the immunological characteristics of a self-amplifying RNA (saRNA) vaccine expressing the SARS-CoV-2 Spike (S) receptor binding domain (RBD), which is membrane-anchored by fusing with an N-terminal signal sequence and a C-terminal transmembrane domain (RBD-TM). Immunization with saRNA RBD-TM delivered in lipid nanoparticles (LNP) efficiently induces T-cell and B-cell responses in non-human primates (NHPs). In addition, immunized hamsters and NHPs are protected against SARS-CoV-2 challenge. Importantly, RBD-specific antibodies against VOCs are maintained for at least 12 months in NHPs. These findings suggest that this saRNA platform expressing RBD-TM will be a useful vaccine candidate inducing durable immunity against emerging SARS-CoV-2 strains.


Assuntos
COVID-19 , Vacinas , Animais , Cricetinae , Humanos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Motivo de Reconhecimento de RNA , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Neutralizantes , Anticorpos Antivirais
12.
Clin Exp Med ; 23(7): 3663-3670, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37027067

RESUMO

PURPOSE: The long-term symptoms of coronavirus disease 2019 (COVID-19), i.e., long COVID, have drawn research attention. Evaluating its subjective symptoms is difficult, and no established pathophysiology or treatment exists. Although there are several reports of long COVID classifications, there are no reports comparing classifications that include patient characteristics, such as autonomic dysfunction and work status. We aimed to classify patients into clusters based on their subjective symptoms during their first outpatient visit and evaluate their background for these clusters. METHODS: Included patients visited our outpatient clinic between January 18, 2021, and May 30, 2022. They were aged ≥ 15 years and confirmed to have SARS-CoV-2 infection and residual symptoms lasting at least 2 months post-infection. Patients were evaluated using a 3-point scale for 23 symptoms and classified into five clusters (1. fatigue only; 2. fatigue, dyspnea, chest pain, palpitations, and forgetfulness; 3. fatigue, headache, insomnia, anxiety, motivation loss, low mood, and forgetfulness; 4. hair loss; and 5. taste and smell disorders) using CLUSTER. For continuous variables, each cluster was compared using the Kruskal-Wallis test. Multiple comparison tests were performed using the Dunn's test for significant results. For nominal variables, a Chi-square test was performed; for significant results, a residual analysis was conducted with the adjusted residuals. RESULTS: Compared to patients in other cluster categories, those in cluster categories 2 and 3 had higher proportions of autonomic nervous system disorders and leaves of absence, respectively. CONCLUSIONS: Long COVID cluster classification provided an overall assessment of COVID-19. Different treatment strategies must be used based on physical and psychiatric symptoms and employment factors.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Estudos Transversais , Japão/epidemiologia , Fadiga/epidemiologia
13.
Front Immunol ; 14: 1087473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36742291

RESUMO

More people with a history of prior infection are receiving SARS-CoV-2 vaccines. Understanding the level of protection granted by 'hybrid immunity', the combined response of infection- and vaccine-induced immunity, may impact vaccination strategies through tailored dosing. A total of 36 infected ('prior infection') and 33 SARS-CoV-2 'naïve' individuals participated. Participants provided sera six months after completing a round of BNT162b2 vaccination, to be processed for anti-spike antibody measurements and the receptor binding domain-ACE2 binding inhibition assays. The relationships between antibody titer, groups and age were explored. Anti-spike antibody titers at 6 months post-vaccination were significantly higher, reaching 13- to 17-fold, in the 'prior infection' group. Semi-log regression models showed that participants with 'prior infection' demonstrated higher antibody titer compared with the 'naïve' even after adjusting for age. The enhancement in antibody titer attributable to positive infection history increased from 8.9- to 9.4- fold at age 30 to 19- to 32-fold at age 60. Sera from the 'prior infection' group showed higher inhibition capacity against all six analyzed strains, including the Omicron variant. Prior COVID-19 led to establishing enhanced humoral immunity at 6 months after vaccination. Antibody fold-difference attributed to positive COVID-19 history increased with age, possibly because older individuals are prone to symptomatic infection accompanied by potentiated immune responses. While still pending any modifications of dosing recommendations (i.e. reduced doses for individuals with prior infection), our observation adds to the series of real-world data demonstrating the enhanced and more durable immune response evoked by booster vaccinations following prior infection.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Pessoa de Meia-Idade , Vacina BNT162 , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , SARS-CoV-2 , Adulto
14.
J Infect Dis ; 227(6): 780-787, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36546706

RESUMO

BACKGROUND: Cross-neutralizing capacity of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants is important in mitigating (re-)exposures. Role of antibody maturation, the process whereby selection of higher affinity antibodies augments host immunity, to determine SARS-CoV-2 neutralizing capacity was investigated. METHODS: Sera from SARS-CoV-2 convalescents at 2, 6, or 10 months postrecovery, and BNT162b2 vaccine recipients at 3 or 25 weeks postvaccination, were analyzed. Anti-spike IgG avidity was measured in urea-treated ELISAs. Neutralizing capacity was assessed by surrogate neutralization assays. Fold change between variant and wild-type neutralization inferred the breadth of neutralizing capacity. RESULTS: Compared with early-convalescent, avidity indices of late-convalescent sera were significantly higher (median, 37.7 [interquartile range 28.4-45.1] vs 64.9 [57.5-71.5], P < .0001). Urea-resistant, high-avidity IgG best predicted neutralizing capacity (Spearman r = 0.49 vs 0.67 [wild-type]; 0.18-0.52 vs 0.48-0.83 [variants]). Higher-avidity convalescent sera better cross-neutralized SARS-CoV-2 variants (P < .001 [Alpha]; P < .01 [Delta and Omicron]). Vaccinees only experienced meaningful avidity maturation following the booster dose, exhibiting rather limited cross-neutralizing capacity at week 25. CONCLUSIONS: Avidity maturation was progressive beyond acute recovery from infection, or became apparent after the booster vaccine dose, granting broader anti-SARS-CoV-2 neutralizing capacity. Understanding the maturation kinetics of the 2 building blocks of anti-SARS-CoV-2 humoral immunity is crucial.


Assuntos
Vacina BNT162 , COVID-19 , Humanos , Afinidade de Anticorpos , Soroterapia para COVID-19 , SARS-CoV-2 , Ureia , Vacinação , Imunoglobulina G , Anticorpos Neutralizantes , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus
16.
J Infect Chemother ; 29(2): 223-227, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36379403

RESUMO

Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) is being increasingly recognized as a severe complication that contributes to poor prognoses among patients with COVID-19. However, little is known regarding the clinical course of CAPA with hematological malignancies, especially after allogeneic hematopoietic stem cell transplantation (HSCT). A 29-year-old woman was diagnosed with proven CAPA with an Aspergillus fumigatus identified by cultures of bronchoalveolar lavage and lung biopsy four years after haploidentical HSCT for acute myelogenous leukemia. She had been taking oral prednisolone for bronchiolitis obliterans syndrome that developed after HSCT. Although prolonged RT-PCR positivity for SARS-CoV-2 (133 days after the onset of COVID-19) without shedding of viable virus was observed, the COVID-19 was treated with favipiravir, remdesivir, dexamethasone, and enoxaparin. However, the CAPA did not respond to combination therapy, which included triazole (voriconazole, itraconazole, posaconazole) and echinocandin (caspofungin, micafungin), even though the Aspergillus fumigatus isolate was found to be susceptible to these agents in vitro. Nevertheless, a total of 16 weeks of liposomal amphotericin B (L-AMB) therapy led to a favorable response, and the patient was discharged from the hospital on day 213. This case provided essential experience of CAPA treated with L-AMB in a recipient with chronic respiratory disease after HSCT.


Assuntos
Síndrome de Bronquiolite Obliterante , COVID-19 , Transplante de Células-Tronco Hematopoéticas , Aspergilose Pulmonar , Feminino , Humanos , Adulto , Antifúngicos/uso terapêutico , COVID-19/complicações , SARS-CoV-2 , Aspergilose Pulmonar/complicações , Aspergilose Pulmonar/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Aspergillus fumigatus
17.
Antioxid Redox Signal ; 38(7-9): 463-479, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36112670

RESUMO

Aims: Cell-cell interactions between hepatocytes (Hep) and other liver cells are key to maintaining liver homeostasis. Cytoglobin (CYGB), expressed exclusively by hepatic stellate cells (HSC), is essential in mitigating mitochondrial oxidative stress. CYGB absence causes Hep dysfunction and evokes hepatocarcinogenesis through an elusive mechanism. CYGB deficiency is speculated to hinder nitric oxide dioxygenase (NOD) activity, resulting in the elevated formation and release of nitric oxide (NO). Hence, we hypothesized that NO accumulation induced by the loss of NOD activity in CYGB-deficient HSC could adversely affect mitochondrial function in Hep, leading to disease progression. Results: NO, a membrane-permeable gas metabolite overproduced by CYGB-deficient HSC, diffuses into the neighboring Hep to reversibly inhibit cytochrome c oxidase (CcO), resulting in the suppression of respiratory function in an electron transport chain (ETC). The binding of NO to CcO is proved using purified CcO fractions from Cygb knockout (Cygb-/-) mouse liver mitochondria. Its inhibitory action toward CcO-specific activity is fully reversed by the external administration of oxyhemoglobin chasing away the bound NO. Thus, these findings indicate that the attenuation of respiratory function in ETC causes liver damage through the formation of excessive reactive oxygen species. Treating Cygb-/- mice with an NO synthase inhibitor successfully relieved NO-induced inhibition of CcO activity in vivo. Innovation and Conclusion: Our findings provide a biochemical link between CYGB-absence in HSC and neighboring Hep dysfunction; mechanistically the absence of CYGB in HSC causes mitochondrial dysfunction of Hep via the inhibition of CcO activity by HSC-derived NO. Antioxid. Redox Signal. 38, 463-479.


Assuntos
Células Estreladas do Fígado , Óxido Nítrico , Camundongos , Animais , Citoglobina/metabolismo , Células Estreladas do Fígado/metabolismo , Óxido Nítrico/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Globinas , Hepatócitos/metabolismo
18.
J Infect Chemother ; 29(1): 112-114, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36167304

RESUMO

Vaccines having aided in escaping the majority of the population from immunological naïvety, our strategies are now shifting towards an increased focus on identifying and protecting the extremely vulnerable. We here describe the results of testing 12 patients, those with lymphoid malignancies having been targeted their B-cells for therapy with rituximab-containing regimens or a Bruton tyrosine kinase inhibitor, for anti-SARS-CoV-2 spike antibodies after receiving the BNT162b2 mRNA vaccine doses. The interval from last dosing of B-cell depletion therapy to SARS-CoV-2 vaccination was at median 5.3 (range 3.1-6.6) months. Using the 'seroprotection' threshold of 775 [BAU/mL] for the anti-spike antibody titer, our finding points out the crucial unresponsiveness of the targeted population with 0/12 (0%) achieving 'seroprotection'. Although IgG seroconversion was observed in 4/12 (33%), supporting the overall benefit of vaccination, the figures still point out a potential need for optimization of practice. IgA was further less responsive (unsuccessful 'seroconversion' in 11/12 (92%)), implicating an underlying class switch defect. Those with depletion on B-cells are caught at a dilemma between, being too early and too late on receiving SARS-CoV-2 vaccines. They wish to get over their immunological naïvety at the earliest, while, in order to assure quality immune memory, are also required to hold the patience for their B-cells to repopulate. Although it remains an issue whether intensified vaccine schedules and/or regimens will lead to stronger immunogenicity or more effective boosters for non-responders, we shall take advantage of every increasing evidence in order to optimize current options.


Assuntos
COVID-19 , Neoplasias , Vacinas Virais , Humanos , Formação de Anticorpos , Vacinas contra COVID-19 , Vacina BNT162 , Switching de Imunoglobulina , Vacinas Virais/farmacologia , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinação , Anticorpos Antivirais , Vacinas de mRNA
19.
Vaccine X ; 15: 100412, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38161985

RESUMO

Background: To evaluate antibody responses against the primary series of vaccination of severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2] vaccines in the staff and residents of Japanese geriatric intermediate care facilities. Methods: All subjects (159 staff and 96 residents) received two doses of the BNT162b2 mRNA vaccine 3 weeks apart. Baseline data of subject were collected using a structured form. Serum samples were collected three times: before vaccination, 3 weeks after the first dose, and 4 weeks after the second dose, and anti-receptor binding domain of the spike protein of SARS-CoV-2 [anti-RBD] IgG was measured using two immunoassays. Results: After the second dose, geometric mean titers [GMT] of anti-RBD with both the Abbott and Roche assay were significantly lower in residents than staff (2282 AU/mL vs. 8505 AU/mL, and 258 U/mL vs. 948 U/mL, respectively). Multivariate analysis of characteristics affecting antibody responses (≥1280 AU/mL for Abbott and > 210 U/mL for Roche) showed lower odds ratios [ORs] for older age (adjusted OR per 10 year increase [aOR] = 0.62, 95 % confidence interval [95 %CI]; 0.38-1.02), steroid usage (aOR = 0.09, 95 %CI; 0.01-0.60) and regular nonsteroidal anti-inflammatory drugs [NSAIDs] usage (aOR = 0.16, 95 %CI; 0.03-0.88). Conclusions: Elderly people and steroid and NSAID users had lower antibody responses following the second vaccine dose.

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