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Hemophagocytic lymphohistiocytosis (HLH) has been recognized as a rare adverse event following the coronavirus disease 2019 (COVID-19) vaccination. We report a case of neuropsychiatric symptoms and refractory HLH in a woman with systemic lupus erythematosus (SLE) after receiving her COVID-19 vaccine treated with belimumab, later found to have intravascular large B-cell lymphoma (IVLBCL) at autopsy. A 61-year-old woman with SLE was referred to our hospital because of impaired consciousness and fever. One month prior to consulting, she received her second COVID-19 vaccine dose. Afterward, her consciousness level decreased, and she developed a high fever. She tested negative for SARS-CoV-2. Neuropsychiatric SLE was suspected; therefore, glucocorticoid pulse therapy was initiated on day 1 and 8. She had thrombocytopenia, increased serum ferritin levels and hemophagocytosis. The patient was diagnosed with HLH and treated with etoposide, dexamethasone and cyclosporine. Despite treatment, the patient died on day 75; autopsy report findings suggested IVLBCL as the underlying cause of HLH. Differentiating comorbid conditions remains difficult; however, in the case of an atypical clinical presentation, other causes should be considered. Therefore, we speculate that the COVID-19 vaccination and her autoimmune condition may have expedited IVLBCL development.
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Vacinas contra COVID-19 , COVID-19 , Lúpus Eritematoso Sistêmico , Linfo-Histiocitose Hemofagocítica , Linfoma Difuso de Grandes Células B , SARS-CoV-2 , Humanos , Linfo-Histiocitose Hemofagocítica/etiologia , Feminino , Lúpus Eritematoso Sistêmico/complicações , Pessoa de Meia-Idade , Evolução Fatal , COVID-19/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , Vacinação/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/uso terapêuticoRESUMO
Bloom syndrome (BS) is an autosomal recessive genetic disorder caused by variants in the BLM gene. BS is characterized by distinct facial features, elongated limbs, and various dermatological complications including photosensitivity, poikiloderma, and telangiectatic erythema. The BLM gene encodes a RecQ helicase critical for genome maintenance, stability, and repair, and a deficiency in functional BLM protein leads to genomic instability and high predisposition to various types of cancers, particularly hematological and gastrointestinal malignancies. Here, we report a case of BS with a previously unreported variant in the BLM gene. The patient was a 34-year-old woman who presented with short stature, prominent facial features, and a history of malignancies, including lymphoma, breast cancer, and myelodysplastic syndromes (MDS). She was initially treated with azacitidine for MDS and showed transient improvement, but eventually died at age of 35 due to progression of MDS. Genetic screening revealed compound heterozygous variants in the BLM gene, with a recurrent variant previously reported in BS in one allele and a previously unreported variant in the other allele. Based on her characteristic clinical features and the presence of heterozygous variants in the BLM gene, she was diagnosed with BS harboring compound heterozygous BLM variants.
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Síndrome de Bloom , Síndromes Mielodisplásicas , RecQ Helicases , Humanos , Síndrome de Bloom/genética , Feminino , RecQ Helicases/genética , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/tratamento farmacológico , Adulto , Azacitidina/efeitos adversos , Azacitidina/uso terapêutico , Evolução Fatal , Mutação , HeterozigotoRESUMO
BACKGROUND: IL-18 and IL-1ß play a central role in the pathogenesis of systemic juvenile idiopathic arthritis and its life-threatening complication, macrophage activation syndrome (MAS). OBJECTIVES: This study aimed to clarify the role of IL-18 and IL-1ß in the pathogenesis of MAS. METHODS: We developed a mouse model to evaluate the role of each cytokine with Toll-like receptor 9 stimulation after continuous infusion with IL-18, IL-1ß, and a combination of both for 7 days. The symptoms and laboratory findings were compared among the IL-18, IL-1ß, and combination (IL-18+IL-1ß) groups. RESULTS: Body weight was significantly decreased in the IL-1ß and combination groups. Splenomegaly was observed in all groups, whereas hepatomegaly was noted in the IL-18 group only. Decreased T-cell numbers, anemia, and thrombocytopenia were observed in the combination group. IFN-γ, CXCL9, and IL-12A mRNA levels were upregulated and IL-10 mRNA levels in the spleen were downregulated in the IL-18 group. Hepatomegaly and splenomegaly in the IL-18 group were observed in a dose-dependent manner. TNF-α, CXCL9, and IL-12A mRNA levels were upregulated only in those mice with extremely elevated plasma IL-18 levels. CONCLUSION: IL-18 and IL-1ß have distinct roles in the pathogenesis of MAS. Dual blockade of IL-18 and IL-1ß might be necessary to treat MAS.
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Bloom syndrome (BS) is a rare autosomal recessive disorder characterized by genomic instability that leads to various complications, including cancer. Given the low prevalence of BS in Japan, we conducted a nationwide survey. We recruited eight patients with BS, three of whom exhibited intellectual disability. The 631delCAA mutation in the BLM gene was detected in 9 out of 16 alleles. To investigate neuronal development in patients with BS, we generated induced pluripotent stem cells derived from one of these patients (BS-iPSCs). We examined the phenotypes of the induced cortical neurons derived from the generated BS-iPSCs using a previously reported protocol; the generated BS-iPSCs showed an approximately 10-times higher frequency of sister-chromatid exchange (SCE) than the control iPSCs. Immunocytochemistry revealed shorter axons and higher proliferative potential in BS-iPSC-derived cortical neurons compared with control iPSCs. To our knowledge, our study is the first to clarify the abnormality of the cortical neuron phenotypes derived from patients with BS. Our findings may help identify the pathogenesis of neuronal differentiation in BS and aid in the development of novel therapeutic agents.
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Síndrome de Bloom , Deficiência Intelectual , Humanos , Síndrome de Bloom/genética , Mutação , Fenótipo , NeurôniosRESUMO
Interleukin (IL)-18 is a pleiotropic, pro-inflammatory cytokine involved in the regulation of innate and adaptive immune responses. IL-18 has attracted increasing attention as a key mediator in autoinflammatory diseases associated with the development of macrophage activation syndrome (MAS) including systemic juvenile idiopathic arthritis and adult-onset Still's disease. In these diseases, dysregulation of inflammasome activity and overproduction of IL-18 might be associated with the development of MAS by inducing natural killer cell dysfunction. Serum IL-18 levels are high in patients with these diseases and therefore are useful for the diagnosis and monitoring of disease activity. In contrast, a recent study revealed the overproduction of IL-18 was present in cases of autoinflammation without susceptibility to MAS such as pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome. The pathogenic and causative roles of IL-18 remain unclear in these autoinflammatory diseases. Further investigations are necessary to clarify the role of IL-18 and its importance as a therapeutic target in the pathogenesis of autoinflammatory diseases.
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Doenças Hereditárias Autoinflamatórias , Síndrome de Ativação Macrofágica , Acne Vulgar , Adulto , Artrite Infecciosa , Citocinas , Doenças Hereditárias Autoinflamatórias/diagnóstico , Humanos , Inflamassomos , Interleucina-18 , Síndrome de Ativação Macrofágica/diagnóstico , Pioderma GangrenosoRESUMO
OBJECTIVES: To evaluate the efficacy and safety of tocilizumab (TCZ), an interleukin 6 receptor monoclonal antibody, in a subset of Japanese patients with familial Mediterranean fever (FMF). METHODS: We performed a double-blind, randomised, parallel-group trial, followed by an open-label extension trial, in patients with colchicine-resistant or -intolerant FMF (crFMF) (UMIN000028010). Patients were randomly assigned (1:1) to receive TCZ (162 mg every week) or placebo, administered subcutaneously, for 24 weeks. Rescue treatment was allowed if the rescue criteria were met. The primary endpoint was the number of fever attacks over the 24 weeks of treatment. Secondary endpoints included the frequency of accompanying symptoms during attacks, serum CRP and SAA values, and adverse events (AEs). The open-label extension study evaluated the long-term safety and efficacy of TCZ in patients who had completed the preceding study (UMIN000032557). RESULTS: We randomly assigned 23 patients to either TCZ (n=1) or placebo (n=12). The TCZ-placebo rate ratios were 0.691 (95% confidence intervals (CI), 0.189-2.531; p=0.577) for the fever attacks, based on the group rates per week. The recurrence of attacks was significantly lower in the TCZ group (hazard ratio = 0.457; 95% CI, 0.240-0.869). Fever attacks, accompanying symptoms, serum CRP and SAA values were controlled in most of the patients who received long-term TCZ. In these trials, the numbers and severity of AEs did not differ between groups. CONCLUSIONS: Although a primary endpoint was not met in the preceding trial, long-term administration of TCZ showed stable efficacy and safety for patients with crFMF.
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Anticorpos Monoclonais Humanizados , Febre Familiar do Mediterrâneo , Anticorpos Monoclonais Humanizados/efeitos adversos , Colchicina/efeitos adversos , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/tratamento farmacológico , Humanos , Resultado do TratamentoRESUMO
Among the different etiologies for fever of unknown origin in children, infectious diseases are the most frequent final diagnosis, followed by autoimmune diseases and malignancies. Autoinflammatory diseases are relatively rare among children and are frequently overlooked as differential diagnoses for fever of unknown origin. Once the possibility of a particular autoimmune disease is considered by physicians, the diagnosis might be easily made by a genetic approach because many of autoinflammatory diseases are of monogenic origin. To reach the diagnosis, detailed history-taking, precise physical examinations, and cytokine profiling as well as extensive mutation analysis of candidate genes should be undertaken for febrile children. Such the approach will protect the patients, and their family to undergo "diagnostic odyssey" in which unnecessary and sometimes risky diagnostic and therapeutic interventions are taken.This short review discusses the clinical and laboratory features of familial Mediterranean fever and systemic juvenile idiopathic arthritis, as representative illnesses of monogenic and polygenic autoinflammatory diseases, respectively. Cytokine profiling and mutation analyses both help to understand and decipher the heterogeneous pathologies in both disease categories.
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Pseudohypoparathyroidism type 1a (PHP1a) is a genetic disorder caused by heterozygous loss-of-function mutations on the maternal allele of the GNAS gene. Patients with PHP1a predominantly exhibit parathyroid hormone (PTH) resistance and physical features of Albright's hereditary osteodystrophy. We report two unrelated cases with PHP1a who developed tertiary hyperparathyroidism (HPT). Molecular analyses of the GNAS gene identified a previously known heterozygous 4-bp deletion (c. 565_568delGACT) in exon 7 in case 1 and a novel heterozygous missense mutation (p.Lys233Glu) in exon 9 in case 2. Both patients developed tertiary HPT associated with hyperfunctioning parathyroid glands during long-term treatment of hypocalcemia. Case 1 had severe osteoporosis and underwent parathyroidectomy. Case 2 was asymptomatic with no evidence of bone diseases associated with tertiary HPT. PHP1a patients are at risk of developing tertiary HPT and should be treated with sufficient doses of calcium and vitamin D to achieve serum PTH levels within the mid - normal to double the upper limit of the normal range, regardless of serum calcium levels.
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A subarachnoid pleural fistula - a connection between the pleural cavity and the subarachnoid space - generally presents after trauma or surgery. A 1-year 11-month-old girl without a history of trauma or surgery presented with fatigue, cyanosis and dyspnoea. A chest radiograph and computed tomography (CT) demonstrated a massive pleural effusion in the right hemithorax. About 300 ml of a crystal-clear pleural effusion, which looked like pure water, was removed by insertion of a chest drain, but it continued to collect. Cisternography and CT myelography confirmed leakage of cerebral spinal fluid into the right pleural cavity around the thoracolumbar region. Magnetic resonance imaging demonstrated an 11-mm enhanced nodule in the epidural space around the right lumbar (L) 1/2 intervertebral foramen. The patient underwent surgery and epidural tumours attached to the L1 nerve root foramen were completely resected and a fistula of the dura adjacent to the tumour was sutured. Histopathological examination demonstrated a mature teratoma containing a pancreatic component. On retrospective analysis of stored pleural fluid, a raised level of pancreatic enzymes was detected. It is presumed that digestive enzymes secreted by the pancreatic component of the teratoma lysed the dura, resulting in formation of the fistula. When a crystal-clear pleural effusion is present, even in the absence of trauma or surgery, a subarachnoid pleural fistula should be considered. As far as we know, this is the first report of a subarachnoid pleural fistula caused by a paravertebral teratoma.Abbreviations: CSF: cerebrospinal fluid; CT: computed tomography; 111In-DTPA: indium-111 diethylene triamine penta-acetic acid; MRI: magnetic resonance imaging; NIPPV: non-invasive positive pressure ventilation.
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Fístula , Doenças Pleurais , Derrame Pleural , Teratoma , Feminino , Fístula/diagnóstico , Fístula/etiologia , Fístula/cirurgia , Humanos , Lactente , Doenças Pleurais/diagnóstico , Doenças Pleurais/etiologia , Doenças Pleurais/cirurgia , Derrame Pleural/complicações , Derrame Pleural/diagnóstico , Estudos Retrospectivos , Espaço Subaracnóideo , Teratoma/complicaçõesRESUMO
Acute leukemia is typically diagnosed from presenting features related to hematological symptoms, but certain patients present with prominent musculoskeletal pain without signs of hematological abnormality. We reviewed the medical records of 58 children diagnosed with acute lymphoblastic leukemia (ALL) at our hospital to evaluate initial features. Forty six of these patients had hematological symptoms, anemia, or hemorrhage (Group H), while 12 patients had prominent musculoskeletal pain without hematological symptoms (Group P). Diagnosis of leukemia took significantly more time for those 12 patients (Group H, 17.1 days; Group P, 48.5 days). In three of the 12 patients in Group P, localized abnormal imaging findings and unremarkable blood test results led to initial diagnoses of chronic recurrent multifocal osteomyelitis, bone fracture, and septic osteomyelitis. However, 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) revealed multiple intense bone foci or systemic bone marrow uptake, leading to the diagnosis of ALL. A review of 18F-FDG-PET results from 23 patients with ALL who underwent a PET scan (Group H, n = 15; Group P, n = 8) showed multiple bone foci or systemic bone marrow uptake in all cases. In conclusion, lack of hematological symptoms in ALL patients can delay diagnosis, and 18F-FDG-PET is useful for diagnosing leukemia in such cases.
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Tomografia por Emissão de Pósitrons , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico por imagem , Osso e Ossos/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Fluordesoxiglucose F18/análise , Humanos , Masculino , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/análiseRESUMO
We herein report a 36-year-old man with repeated necrotizing lymphadenitis due to MEFV gene mutations. The patient's chief complaints were a fever and painful cervical lymphadenopathy. We diagnosed him with necrotizing lymphadenitis based on the pathological findings of the lymph nodes and the exclusion of other differential diseases. The same episode recurred four times. We speculated the involvement of autoinflammatory backgrounds and detected MEFV gene mutations of E148Q (homo), P369S, and R408Q. Considering the elevation of interleukin-18, these mutations probably played roles in the repeated necrotizing lymphadenitis.
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Linfadenite , Adulto , Febre , Humanos , Linfonodos , Masculino , Mutação/genética , Dor , Pirina/genéticaRESUMO
BACKGROUND: Familial Mediterranean fever (FMF) is an autosomal recessive disease caused by mutations in the MEFV gene. Mutations in exon 10 are associated with typical FMF. Most Japanese patients with typical FMF are compound heterozygotes of M694I in exon 10 and E148Q in exon 2. However, the pathogenic role of E148Q remains controversial. METHODS: We assessed symptoms and serum cytokines among patients with FMF and their family members. They were divided into three subgroups, based on MEFV mutations: individuals carrying M694I and E148Q (group A, n = 14), individuals carrying M694I, but not E148Q (group B, n = 10), and individuals carrying E148Q, but not M694I (group C, n = 11). RESULTS: All but one individual in group A had typical FMF phenotypes, whereas no individual in groups B and C exhibited any episodes of fever or serositis. The serum levels of interleukin-18 during the afebrile phase were significantly elevated in group A (2,806 ± 2,107 pg/mL), compared to those in groups B (499 ± 369 pg/mL) and C (427 ± 410 pg/mL). No difference in interleukin-6 levels was observed among the three groups. CONCLUSIONS: These findings indicated that E148Q may contribute to disease development of FMF in Japanese patients carrying the heterozygous M694I mutation in MEFV and that genetic testing of both parents would lead to better counseling for their children.
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Febre Familiar do Mediterrâneo , Éxons/genética , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/genética , Heterozigoto , Humanos , Mutação , Pirina/genéticaRESUMO
OBJECTIVE: To identify potential biomarkers to distinguish familial Mediterranean fever (FMF) from sepsis. METHOD: We recruited 28 patients diagnosed with typical FMF (according to the Tel Hashomer criteria), 22 patients with sepsis, and 118 age-matched controls. Serum levels of 40 cytokines were analyzed using multi-suspension cytokine array. We performed a cluster analysis of each cytokine in the FMF and sepsis groups in order to identify specific molecular networks. Multivariate classification (random forest analysis) and logistic regression analysis were used to rank the cytokines by importance and determine specific biomarkers for distinguishing FMF from sepsis. RESULTS: Fifteen of the 40 cytokines were found to be suitable for further analysis. Levels of serum granulocyte-macrophage colony-stimulating factor (GM-CSF), fibroblast growth factor 2, vascular endothelial growth factor, macrophage inflammatory protein-1b, and interleukin-17 were significantly elevated, whereas tumor necrosis factor-α (TNF-α) was significantly lower in patients with FMF compared with those with sepsis. Cytokine clustering patterns differed between the two groups. Multivariate classification followed by logistic regression analysis revealed that measurement of both GM-CSF and TNF-α could distinguish FMF from sepsis with high accuracy (cut-off values for GM-CSF = 8.3 pg/mL; TNF-α = 16.3 pg/mL; sensitivity, 92.9%; specificity, 94.4%; accuracy, 93.4%). CONCLUSION: Determination of GM-CSF and TNF-α levels in combination may represent a biomarker for the differential diagnosis of FMF from sepsis, based on measurement of multiple cytokines.
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Febre Familiar do Mediterrâneo , Sepse , Biomarcadores , Febre Familiar do Mediterrâneo/diagnóstico , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Sepse/diagnóstico , Fator de Necrose Tumoral alfa , Fator A de Crescimento do Endotélio VascularAssuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Eritema/patologia , Dermatoses do Pé/patologia , Metotrexato/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Criança , Eritema/induzido quimicamente , Dermatoses do Pé/induzido quimicamente , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , PrognósticoRESUMO
BACKGROUND: Insulin-like growth factor-binding protein (IGFBP) 2 plays an important role in the regulation of cell adhesion, migration, growth, and apoptosis. This study aimed to investigate the clinical significance of serum IGFBP2 as a biomarker for disease activity and severity in hemolytic uremic syndrome (HUS) induced by enterohemorrhagic Escherichia coli (EHEC). METHODS: IGFBP2 production by human renal glomerular endothelial cells (RGECs) after exposure to Shiga toxin 2 (Stx-2) was investigated in vitro. Serum IGFBP2 levels in blood samples obtained from 22 patients with HUS and 10 healthy controls (HCs) were quantified using an enzyme-linked immunosorbent assay. The results were compared to the clinical features of HUS and serum tau and cytokine levels. RESULTS: Stx-2 induced the production of IGFBP2 in RGECs in a dose-dependent manner. Serum IGFBP2 levels were significantly higher in patients with HUS than in HCs and correlated with disease severity. Additionally, serum IGFBP2 levels were significantly higher in patients with encephalopathy than in those without encephalopathy. A serum IGFBP2 level above 3585 pg/mL was associated with a high risk of encephalopathy. Furthermore, serum IGFBP2 levels significantly correlated with serum levels of tau and inflammatory cytokines associated with the development of HUS. CONCLUSIONS: Correlation of serum IGFBP2 level with disease activity in patients with HUS suggests that IGFBP2 may be considered as a possible indicator for disease activity and severity in HUS. Larger studies and additional experiments using various cells in central nervous system should elucidate the true value of IGFBP2 as a clinical diagnostic marker. ABBREVIATIONS: IGFBP: insulin-like growth factor-binding protein; HUS: hemolytic uremic syndrome; EHEC: enterohemorrhagic Escherichia coli; RGECs: renal glomerular endothelial cells; STx-2: Shiga toxin 2; HCs: healthy controls; LPS: lipopolysaccharide; ROC: receiver operating characteristic; sTNFR: soluble tumor necrosis factor receptor.
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Escherichia coli Êntero-Hemorrágica/patogenicidade , Infecções por Escherichia coli/microbiologia , Síndrome Hemolítico-Urêmica/sangue , Síndrome Hemolítico-Urêmica/microbiologia , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Infecções por Escherichia coli/complicações , Feminino , Síndrome Hemolítico-Urêmica/patologia , Humanos , Lactente , Masculino , Curva ROC , Índice de Gravidade de Doença , Adulto JovemRESUMO
The components of ginger root (Zingiber officinale Roscoe) are widely used for various medicinal purposes. Several bioactive compounds have been identified in ginger, including 6, 8 and 10gingerols, and 6shogaol, which are agonists of the thermosensors transient receptor potential (TRP) cation channel subfamily V member 1 and TRP ankyrin 1. Our previous study demonstrated that ginger powder may affect human metabolism in vivo. However, the effects of the bioactive compounds of ginger on cells have not been completely elucidated. The present study investigated whether ginger powder extracts could modify cell functions in mouse fibroblast cells. The active components of ginger powder extracts were characterized using highperformance liquid chromatography. The activation of protein kinases, actin assembly, cell migration, expression levels of heat shock proteins (HSPs) and cell viability after heat shock were analyzed in NIH3T3 mouse fibroblast cells. Subsequently, 6, 8, 10 and 12gingerols, as well as 6, 8 and 10shogaols, were detected in ginger powder extracts. The levels of phosphorylated Akt, mTOR, ERK and p38 MAPK increased after a 10min stimulation with ginger powder extracts. In addition, HSP expression levels, lamellipodia formation occurring at cell edges, cell migration and tolerance against heat shock were facilitated following ginger powder extract stimulation. These results suggest that ginger modified cell functions, including actin assembly and heat tolerance, in vitro.
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Fibroblastos/metabolismo , Resposta ao Choque Térmico/efeitos dos fármacos , Temperatura Alta , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Extratos Vegetais/farmacologia , Zingiber officinale/química , Animais , Movimento Celular , Camundongos , Células NIH 3T3 , Extratos Vegetais/químicaRESUMO
Since Yachie et al. reported the first description of human heme oxygenase (HO)-1 deficiency more than 20 years ago, few additional human cases have been reported in the literature. A detailed analysis of the first human case of HO-1 deficiency revealed that HO-1 is involved in the protection of multiple tissues and organs from oxidative stress and excessive inflammatory reactions, through the release of multiple molecules with anti-oxidative stress and anti-inflammatory functions. HO-1 production is induced in vivo within selected cell types, including renal tubular epithelium, hepatic Kupffer cells, vascular endothelium, and monocytes/macrophages, suggesting that HO-1 plays critical roles in these cells. In vivo and in vitro studies have indicated that impaired HO-1 production results in progressive monocyte dysfunction, unregulated macrophage activation and endothelial cell dysfunction, leading to catastrophic systemic inflammatory response syndrome. Data from reported human cases of HO-1 deficiency and numerous studies using animal models suggest that HO-1 plays critical roles in various clinical settings involving excessive oxidative stress and inflammation. In this regard, therapy to induce HO-1 production by pharmacological intervention represents a promising novel strategy to control inflammatory diseases.
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Anemia Hemolítica/metabolismo , Transtornos do Crescimento/metabolismo , Heme Oxigenase-1/deficiência , Heme Oxigenase-1/metabolismo , Distúrbios do Metabolismo do Ferro/metabolismo , Estresse Oxidativo , Animais , Humanos , InflamaçãoRESUMO
BACKGROUND: Exotoxins secreted from Staphylococcus aureus or Streptococcus pyogenes act as superantigens that induce systemic release of inflammatory cytokines and are a common cause of toxic shock syndrome (TSS). However, little is known about TSS caused by coagulase-negative staphylococci (CoNS) and the underlying mechanisms. Here, we present a rare case of TSS caused by Staphylococcus simulans (S. simulans). CASE PRESENTATION: We report the case of a 75-year-old woman who developed pneumococcal pneumonia and bacteremia from S. simulans following an influenza infection. The patient met the clinical criteria for probable TSS, and her symptoms included fever of 39.5 °C, diffuse macular erythroderma, conjunctival congestion, vomiting, diarrhea, liver dysfunction, and disorientation. Therefore, the following treatment was initiated for bacterial pneumonia complicating influenza A with suspected TSS: meropenem (1 g every 8 h), vancomycin (1 g every 12 h), and clindamycin (600 mg every 8 h). Blood cultures taken on the day after admission were positive for CoNS, whereas sputum and pharyngeal cultures grew Streptococcus pneumoniae (Geckler group 4) and methicillin-sensitive S. aureus, respectively. However, exotoxins thought to cause TSS, such as TSS toxin-1 and various enterotoxins, were not detected. The patient's therapy was switched to cefazolin (2 g every 8 h) and clindamycin (600 mg every 8 h) for 14 days based on microbiologic test results. She developed desquamation of the fingers on hospital day 8 and was diagnosed with TSS. Conventional exotoxins, such as TSST-1, and S. aureus enterotoxins were not detected in culture samples. The serum levels of inflammatory cytokines, such as neopterin and IL-6, were high. CD8+ T cells were activated in peripheral blood. Vß2+ population activation, which is characteristic for TSST-1, was not observed in the Vß usage of CD8+ T cells in T cell receptor Vß repertoire distribution analysis. CONCLUSIONS: We present a case of S. simulans-induced TSS. Taken together, we speculate that no specific exotoxins are involved in the induction of TSS in this patient. A likely mechanism is uncontrolled cytokine release (i.e., cytokine storm) induced by non-specific immune reactions against CoNS proliferation.