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1.
Parasit Vectors ; 17(1): 164, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555448

RESUMO

BACKGROUND: The immunocompetence handicap hypothesis suggests that males with a higher testosterone level should be better at developing male secondary traits, but at a cost of suppressed immune performance. As a result, we should expect that males with an increased testosterone level also possess a higher parasite load. However, previous empirical studies aimed to test this prediction have generated mixed results. Meanwhile, the effect of testosterone level on parasite load in female hosts remains poorly known. METHODS: In this study, we tested this prediction by manipulating testosterone level in Daurian ground squirrels (Spermophilus dauricus), a medium-sized rodent widely distributed in northeast Asia. S. dauricus is an important host of ticks and fleas and often viewed as a considerable reservoir of plague. Live-trapped S. dauricus were injected with either tea oil (control group) or testosterone (treatment group) and then released. A total of 10 days later, the rodents were recaptured and checked for ectoparasites. Fecal samples were also collected to measure testosterone level of each individual. RESULTS: We found that testosterone manipulation and sex of hosts interacted to affect tick load. At the end of the experiment, male squirrels subjected to testosterone implantation had an averagely higher tick load than males from the control group. However, this pattern was not found in females. Moreover, testosterone manipulation did not significantly affect flea load in S. dauricus. CONCLUSIONS: Our results only lent limited support for the immunocompetence handicap hypothesis, suggesting that the role of testosterone on regulating parasite load is relatively complex, and may largely depend on parasite type and gender of hosts.


Assuntos
Infestações por Pulgas , Doenças dos Roedores , Sifonápteros , Carrapatos , Animais , Feminino , Masculino , Sciuridae/parasitologia , Infestações por Pulgas/veterinária , Testosterona/fisiologia , Imunocompetência/fisiologia
4.
N Engl J Med ; 390(6): 522-529, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38324485

RESUMO

A multinational outbreak of nosocomial fusarium meningitis occurred among immunocompetent patients who had undergone surgery with epidural anesthesia in Mexico. The pathogen involved had a high predilection for the brain stem and vertebrobasilar arterial system and was associated with high mortality from vessel injury. Effective treatment options remain limited; in vitro susceptibility testing of the organism suggested that it is resistant to all currently approved antifungal medications in the United States. To highlight the severe complications associated with fusarium infection acquired in this manner, we report data, clinical courses, and outcomes from 13 patients in the outbreak who presented with symptoms after a median delay of 39 days.


Assuntos
Surtos de Doenças , Fusariose , Fusarium , Doença Iatrogênica , Meningite Fúngica , Humanos , Antifúngicos/uso terapêutico , Fusariose/epidemiologia , Fusariose/etiologia , Fusarium/isolamento & purificação , Doença Iatrogênica/epidemiologia , Meningite Fúngica/epidemiologia , Meningite Fúngica/etiologia , México/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Internacionalidade , Imunocompetência , Farmacorresistência Fúngica , Analgesia Epidural/efeitos adversos
7.
Virol J ; 21(1): 39, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336670

RESUMO

Pneumonia is the most common complication of varicella infections. Although previous studies have tended to focus mainly on immunocompromised patients, varicella pneumonia can also occur in healthy adults. Therefore, in this study, we aimed to assess the progression of varicella pneumonia in immunocompetent hosts. This retrospective study involved immunocompetent adult outpatients with varicella who attended the adult Fever Emergency facility of Peking University Third Hospital from April 1, 2020, to October 31, 2022. Varicella pneumonia was defined as a classic chickenpox-type rash in patients with infiltrates on chest computed tomography. The study included 186 patients, 57 of whom had a contact history of chickenpox exposure. Antiviral pneumonia therapy was administered to 175 patients by treating physicians. Computed tomography identified pneumonia in 132 patients, although no deaths from respiratory failure occurred. Seventy of the discharged patients were subsequently contacted, all of whom reported being well. Follow-up information, including computed tomography findings, was available for 37 patients with pneumonia, among whom 24 reported complete resolution whereas the remaining 13 developed persistent calcifications. Notably, we established that the true incidence of varicella pneumonia is higher than that previously reported, although the prognosis for immunocompetent hosts is generally good.


Assuntos
Varicela , Pneumonia Viral , Adulto , Humanos , Varicela/complicações , Varicela/epidemiologia , Estudos Retrospectivos , Prevalência , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Imunocompetência , Herpesvirus Humano 3
8.
Immun Inflamm Dis ; 12(1): e1134, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38270318

RESUMO

INTRODUCTION: This study aimed to investigate the role of immunocompetence in chronic hepatitis B (CHB) patients with normal alanine transaminase (ALT) levels and negative hepatitis B e antigen (HBeAg) in the risk assessments of the progression of liver fibrosis. METHODS: We collected the clinical data of 57 patients with CHB, with normal ALT levels and negative HBeAg from December 2020 to December 2022. With hepatitis B virus (HBV) DNA > 20 IU/mL and ALT ≤ 40 U/L, these patients had never undergone antiviral therapy. The levels of CD4+ , CD4+ CD25+ , CD8+ , and CD4+ CD25+ CD127LOW regulatory T cells (Tregs) in the patients were detected using flow cytometry; the liver stiffness measurement (LSM) values of the patients were detected using Fibroscan. RESULTS: There was a statistically significant difference between the levels of fibrosis-4 (FIB-4) and hepatitis B surface antigen (HBsAg) when the cutoff point was HBsAg ≥ 1500 (p < .001). FIB-4 was negatively correlated with HBsAg (R = -0.291, p = .028) and positively correlated with age (R = 0.787, p < .001). LSM was negatively correlated with Treg but this correlation was not statistically significant (p > .05). Findings based on the analysis using logistic regression were as follows: (i) age was the independent risk factor when FIB-4 was used as the indicator for assessing liver fibrosis; (ii) Treg was the independent risk factor when LSM was used as the indicator for assessing liver fibrosis. When Treg was used to predict liver fibrosis, the cutoff value, diagnostic efficacy, area under the receiver operating characteristic (ROC) curve, and p value of the ROC curve were 6.875, 0.641, 0.84, and .027, respectively. CONCLUSION: Age and Treg are independent risk factors for progressive liver fibrosis. The cutoff value of Treg > 6.81 indicates the need for timely antiviral treatment and can serve as an indicator for evaluating liver fibrosis.


Assuntos
Antígenos E da Hepatite B , Hepatite B , Humanos , Alanina Transaminase , Antígenos de Superfície da Hepatite B , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Hepatite Crônica , Imunocompetência
10.
Z Rheumatol ; 83(2): 87-97, 2024 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-37644129

RESUMO

Patients with inflammatory rheumatic diseases have a higher risk of infections in comparison to the general population. For this patient group, in addition to cardiovascular diseases, infections play an important role with respect to morbidity and mortality. Even if it is difficult to make concrete statements with respect to individual diseases, it can be assumed that there is a lower risk of infections in inflammatory joint diseases in comparison to connective tissue diseases and vasculitides. The increased risk of infections is determined by multiple factors, whereby the underlying factors are classified into three main categories: patient-related factors (age, comorbidities, lifestyle), disease-related factors (immunological dysfunction as part of the disease pathophysiology) and drug-related factors (type and dosage of the immunosuppression and/or immunomodulation). An improved understanding of the complexity of these associations enables the optimization of treatment and disease control taking the individual risk factors into account, with the aim of a significant reduction in the risk of infections.


Assuntos
Doenças Reumáticas , Febre Reumática , Humanos , Doenças Reumáticas/epidemiologia , Febre Reumática/epidemiologia , Comorbidade , Terapia de Imunossupressão , Imunocompetência
11.
Chemosphere ; 346: 140630, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939926

RESUMO

Mercury (Hg) is a globally important pollutant that can negatively impact metabolic, endocrine and immune systems of marine biota. Seabirds are long-lived marine top predators and hence are at risk of bioaccumulating high Hg concentrations from their prey. Here, we measured blood total mercury (THg) concentrations and relationships with physiology and breeding parameters of breeding brown skuas (Stercorarius antarcticus) (n = 49 individuals) at Esperanza/Hope Bay, Antarctic Peninsula. Mean blood THg concentrations were similar in males and females despite the differences in body size and breeding roles, but differed between study years. Immune markers (hematocrit, Immunoglobulin Y [IgY] and albumin) were negatively correlated with blood THg concentrations, which likely indicates a disruptive effect of Hg on immunity. Alanine aminotransferase (GPT) activity, reflecting liver dysfunction, was positively associated with blood THg. Additionally, triacylglycerol and albumin differed between our study years, but did not correlate with Hg levels, and so were more likely to reflect changes in diet and nutritional status rather than Hg contamination. Egg volume correlated negatively with blood THg concentrations. Our study provides new insights into the sublethal effects of Hg contamination on immunity, liver function and breeding parameters in seabirds. In this Antarctic species, exposure to sublethal Hg concentrations reflects the short-term risks which could make individuals more susceptible to environmental stressors, including ongoing climatic changes.


Assuntos
Charadriiformes , Mercúrio , Humanos , Masculino , Animais , Feminino , Aves/metabolismo , Mercúrio/análise , Regiões Antárticas , Monitoramento Ambiental , Charadriiformes/metabolismo , Fígado/metabolismo , Imunocompetência , Albuminas/metabolismo
12.
Cell Mol Biol (Noisy-le-grand) ; 69(11): 219-226, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38015517

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a disease characterized by profound immunosuppression and the prognosis of HNSCC patients remains poor. Necroptosis is a programmed lytic cell-death mechanism that can promote tumor growth, angiogenesis, invasion and metastasis. The differentially expressed NRGs were screened by using the LIMMA package of R software (version 4.1.2) and the prognosis-related NRGs were obtained by COX regression analysis. We separated patients into high- and low-risk groups via the prognostic model consisting of those NRGs. The receiver operating characteristic (ROC) curve and Kaplan-Meier survival curves were used to validate the prognostic model. By bioinformatics analysis, the prognostic risk and immunocompetent models were constructed. We reevaluate the prognostic model based on the GES27020 data sets, clinicopathological variables and chemotherapeutic efficacy. Individuals in the high-risk group had much shorter overall survival (OS) times than their counterparts. Compared with clinicopathological variables, the risk model has a higher diagnostic efficiency, with the area under the ROC being 0.699. Decision Curve Analysis (DCA) showed the prognostic model-based risk score was the superior prognostic factor compared to additional indicators. Furthermore, the high- and low-risk groups had differences in immune cell infiltration and immune functions. And the CCK-8 showed that small molecular drugs could inhibit HNSCC cell proliferation in vitro. We have constructed a new necroptosis-related model, which can be used to predict the prognosis and immunocompetence of HNSCC patients and provide a theoretical basis for the study of necroptosis in the clinical prognosis of HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Necroptose , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Imunocompetência , Apoptose , Neoplasias de Cabeça e Pescoço/genética
15.
Nat Plants ; 9(9): 1468-1480, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37591928

RESUMO

Although many studies have shown that microbes can ectopically stimulate or suppress plant immune responses, the fundamental question of whether the entire preexisting microbiota is indeed required for proper development of plant immune response remains unanswered. Using a recently developed peat-based gnotobiotic plant growth system, we found that Arabidopsis grown in the absence of a natural microbiota lacked age-dependent maturation of plant immune response and were defective in several aspects of pattern-triggered immunity. Axenic plants exhibited hypersusceptibility to infection by the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 and the fungal pathogen Botrytis cinerea. Microbiota-mediated immunocompetence was suppressed by rich nutrient conditions, indicating a tripartite interaction between the host, microbiota and abiotic environment. A synthetic microbiota composed of 48 culturable bacterial strains from the leaf endosphere of healthy Arabidopsis plants was able to substantially restore immunocompetence similar to plants inoculated with a soil-derived community. In contrast, a 52-member dysbiotic synthetic leaf microbiota overstimulated the immune transcriptome. Together, these results provide evidence for a causal role of a eubiotic microbiota in gating proper immunocompetence and age-dependent immunity in plants.


Assuntos
Arabidopsis , Microbiota , Nível de Saúde , Imunocompetência , Reconhecimento da Imunidade Inata , Solo
16.
Cell Tissue Res ; 394(2): 309-323, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37572164

RESUMO

Subclinical hypothyroidism (SCH) affects 10% of the global population, which is most prevalent in women and the elderly. However, it remains debatable whether the elderly with subclinical hypothyroidism needs thyroxine supplement. Human amnion-derived mesenchymal stem cells (hAMSCs) could play important roles in autoimmune diseases, suggesting that hAMSC be a candidate to regulate the thyroid function of female age-related subclinical hypothyroidism. Herein, we established the model of SCH in the aged female mice. This study was designed to investigate whether human amnion-derived mesenchymal stem cells (hAMSC) could effect on immune regulation, apoptosis inhibition of thyroid cells, thyroid function, blood lipid levels, and heart function. In addition, qualified hAMSCs were intravenously injected into aged female SCH mice via the tail vein on day 0 and day 10. The levels of thyroid hormone and blood lipids as well as cardiac function, serum immunological indexes, and apoptosis of thyroid cells were then analyzed on day 5, 10, 15, and 20; meanwhile, the quantity of Th1, Th2, Th17, and Treg immune cells in peripheral blood was evaluated before and on day 20 post-injection. Our study demonstrated that after hAMSC transplantation, the thyroid functions, blood lipid levels, and heart function indexes of age-related SCH (AR-SCH) mice were significantly improved. Consistent with this, Th1 and Treg cells increased significantly, while Th2 and Th17 cells decreased in peripheral blood. Apoptosis was also suppressed in the thyroid cells. In summary, hAMSC delivery can potentially be a safe and effective therapy for treating SCH in the elderly, improving related complications by immunomodulatory and apoptosis inhibition.


Assuntos
Hipotireoidismo , Células-Tronco Mesenquimais , Idoso , Humanos , Feminino , Camundongos , Animais , Âmnio , Hipotireoidismo/terapia , Apoptose , Lipídeos , Imunocompetência
17.
J Therm Biol ; 116: 103640, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37542840

RESUMO

Short Periods of Incubation During Egg Storage (SPIDES) approach improves chick quality and hatching rates. Also, embryonic thermal conditioning (TC) is a strategy for enhancing thermotolerance in avian species. Until now, evaluating the effect of either SPIDES or embryonic TC effects has only been separately conducted, so we hypothesized that combining TC and SPIDES may enhance the response of broilers to thermal stress. Eight hundred Ross broiler eggs were divided into two groups; the first one was kept under appropriate storage room conditions, S0 (control) The 2nd was subjected to SPIDES for 5 h at 37.8 ○C ± 0.1 three times at days 5, 10, and 15 (S1) after egg collection respectively. On the 14th day of incubation (DOI) each of the two main groups was randomly divided into two equal subgroups; the control one was left under the appropriate incubation settings (TC0) whereas the other received prenatal heat conditioning (TC1) at 39.5 ○C ± 0.1 for 6 h/d from the 14th to the 18th embryonic day (E), resulting finally in four experimental subgroups (S0TC0, S1TC0, S0TC1 & S1TC1). RESULTS: showed that SPIDES treatment improved the hatchability of the stored eggs by almost 20% compared to untreated eggs. A combination of SPIDES and TC (S1TC1) increased significantly the levels of Immunoglobulin (IgG and IgM) production at hatch and heat-stressed birds. Our findings revealed that the hepatic heat shock proteins (hsp70, 90 A,90 B, 60 and hspA9), antioxidants-related genes (CAT, and SOD2), and NADPH4 were significantly downregulated in the thermally conditioned group that challenged with thermal stress conditions. As opposed to that, the SPIDES group showed a significant increase in hepatic heat shock proteins, antioxidants-related genes, and NADPH4 when subjected to thermal-stress conditions. In conclusion, the combination of SPIDES and TC has a positive effect on some pre and post-hatch traits of broiler chicks. Under heat stress challenge, thermal conditioning can modify the expression of antioxidant-related genes and Hsps, leading to the enhanced acquisition of thermotolerance as evidenced by lower expression of Hsps and NADPH4. While SPIDES does not have a significant role in thermotolerance acquisition.


Assuntos
Galinhas , Proteínas de Choque Térmico , Animais , Galinhas/fisiologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Antioxidantes/metabolismo , Resposta ao Choque Térmico , Imunocompetência
18.
Comp Immunol Microbiol Infect Dis ; 100: 102036, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37541170

RESUMO

Feral birds residing close to urban settings exhibit higher immunocompetence against environmental pathogens than their counterparts in rural areas. In this study, we comprehensively evaluated the immunocompetence of five specific feral bird species and investigated the potential for interspecies transmission and pathogenicity of Avian orthoavulavirus-1 (AOAV-1) originating from the Anseriformes order. The immunocompetence assessment involved administering the phytohemagglutinin (PHA) test to individual groups of birds from rural and urban settings, measuring patagium thickness at specific time intervals (12, 24, 36, 48, and 60 h) following the administration of 0.1 mL (1 mg/mL) of PHA. Urban birds displayed significantly enhanced mean swelling responses, particularly urban pigeons, which exhibited a significant difference in patagium thickness at all-time intervals except for 24 h (p = 0.000, p = 0.12). Similarly, rural and urban quails and crows showed substantial differences in patagium thickness at all-time intervals except for 12 h (p = 0.542, p = 0.29). For the assessment of interspecies transmission potential and pathogenicity, each feral bird group was separately housed with naive broiler birds (n = 10 each) and challenged with a velogenic strain of AOAV-1 isolate (Mallard-II/UVAS/Pak/2016) at a dose of 1 mL (108 EID50/mL). Urban birds demonstrated higher resistance to the virus compared to their rural counterparts. These findings highlight the specific immunocompetence of feral bird species and their potential contributions to AOAV-1 transmission and pathogenicity. Continuous monitoring, surveillance, and strict implementation of biosafety and biosecurity measures are crucial for effectively controlling AOAV-1 spillover to the environment and wild bird populations in resource-limited settings, particularly Pakistan.


Assuntos
Animais Selvagens , Galinhas , Animais , Vírus da Doença de Newcastle/fisiologia , Patos , Imunocompetência
19.
Poult Sci ; 102(10): 102897, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37562125

RESUMO

Ginger contains bioactive compounds that possess anti-inflammatory and antimicrobial properties. In this study, 432-day-old Ross 708 broiler male chicks were randomly allocated to 6 dietary treatments to investigate the effect of ginger root extract (GRE) on immunocompetence and growth performance to 6 wk of age. Treatment 1 (CON) consisted of chicks fed a corn-soybean meal (SBM), a base diet without GRE. Treatment 2 (MX) chicks were given basal diets containing bacitracin methylene disalicylate (BMD) at 0.055 g/kg. Treatments 3 (GRE-0.375%), 4 (GRE-0.75%), 5 (GRE-1.5%), and 6 (GRE-3%) were fed similar diet to control with GRE supplemented at 0.375%, 0.75%, 1.5%, and 3%, respectively. Moreover, HPLC analysis of GRE was carried out to determine the concentration of bioactive compounds found in GRE. Each treatment consisted of 6 replicate pens with 12 chicks/pen. Bodyweight (BW) and feed conversion ratio (FCR) were recorded. Results show that the concentration of bioactive compounds increased with increasing GRE supplementation. Likewise, dietary GRE supplementation did not have any detrimental effect on growth performance parameters up to 1.5%, as values for BWG was not different from CON and MX; however, 3% GRE had the poorest FCR and a lower BWG as compared to other treatments. On d 27 and d 41, fecal and cecal concentrations of total bacteria count (TBC), Escherichia coli, Lactobacillus spp., and Bifidobacterium spp enumerated using selective plating media showed that GRE supplementation significantly reduced (P < 0.05) the amount of TBC and E. coli but increased the number of beneficial microorganisms such as Lactobacillus spp. and Bifidobacterium spp. On d 20, no significant differences were observed (P > 0.05) among all treatments for antibody titer against Newcastle disease virus and total IgY antibodies; however, on d 27, GRE-0.75% had the highest value for both immune indicators and was not different from MX. Dietary supplementation of GRE up to 1.5% enhanced the immune system and suppressed E. coli while promoting the growth of healthy bacteria, without any detrimental effect on growth performance.


Assuntos
Galinhas , Animais , Masculino , Escherichia coli , Dieta/veterinária , Suplementos Nutricionais/análise , Extratos Vegetais/farmacologia , Imunocompetência , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal
20.
Fish Shellfish Immunol ; 140: 108968, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37481103

RESUMO

Among trace metals, copper is essential for crustaceans' normal growth and metabolism. In the present study, an attempt was made to determine whether the addition of copper in rearing water influences the physiological and immunological responses of Penaeus monodon to white spot syndrome virus infection (WSSV). Adult P. monodon were distributed in experimental tanks and exposed to 0, 0.05, 0.1, 0.2 and 0.3 mg l-1 copper concentrations. After 14 days, the shrimps were challenged with WSSV and the biochemical/immune variables were determined on post-metal exposure day 14 and post-challenge days 2 and 5. Significant variations could be observed in the haemolymph (biochemical and immune) variables of P. monodon on exposure to copper and WSSV challenge. Shrimps exposed to copper at 0.1 mg l-1 showed higher total haemocyte count, phenol oxidase activity, nitro blue tetrazolium salt reduction, alkaline/acid phosphatase activity, total protein, carbohydrates, lipids, glucose and cholesterol besides maximum post-challenge survival. However, exposure to copper at 0.2 and 0.3 mgl-1 increased the susceptibility to WSSV infection, showing a decrease in the biochemical/immune variables. Therefore, the present study concludes that copper in ambient water induces immunomodulation and evokes physiological responses in P. monodon at sub-lethal doses. Immunostimulatory effects elicited by copper at 0.1 mg l-1 enhanced the immunocompetence and reduced the susceptibility of P. monodon to WSSV infection, conferring protection to the animals and resulting in higher survival.


Assuntos
Decápodes , Penaeidae , Vírus da Síndrome da Mancha Branca 1 , Animais , Cobre/toxicidade , Vírus da Síndrome da Mancha Branca 1/fisiologia , Imunocompetência
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