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1.
Am J Pathol ; 193(12): 2047-2065, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37741453

RESUMEN

Toxoplasma gondii infection in pregnant women may cause fetal anomalies; however, the underlying mechanisms remain unclear. The current study investigated whether T. gondii induces pyroptosis in human placental cells and the underlying mechanisms. Human placental trophoblast (BeWo and HTR-8/SVneo) and amniotic (WISH) cells were infected with T. gondii, and then reactive oxygen species (ROS) production, cathepsin B (CatB) release, inflammasome activation, and pyroptosis induction were evaluated. The molecular mechanisms of these effects were investigated by treating the cells with ROS scavengers, a CatB inhibitor, or inflammasome-specific siRNA. T. gondii infection induced ROS generation and CatB release into the cytosol in placental cells but decreased mitochondrial membrane potential. T. gondii-infected human placental cells and villi exhibited NLRP1, NLRP3, NLRC4, and AIM2 inflammasome activation and subsequent pyroptosis induction, as evidenced by increased expression of ASC, cleaved caspase-1, and mature IL-1ß and gasdermin D cleavage. In addition to inflammasome activation and pyroptosis induction, adverse pregnancy outcome was shown in a T. gondii-infected pregnant mouse model. Administration of ROS scavengers, CatB inhibitor, or inflammasome-specific siRNA into T. gondii-infected cells reversed these effects. Collectively, these findings show that T. gondii induces NLRP1/NLRP3/NLRC4/AIM2 inflammasome-dependent caspase-1-mediated pyroptosis via induction of ROS production and CatB activation in placental cells. This mechanism may play an important role in inducing cell injury in congenital toxoplasmosis.


Asunto(s)
Inflamasomas , Toxoplasma , Ratones , Animales , Humanos , Femenino , Embarazo , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Piroptosis , Trofoblastos/metabolismo , Catepsina B/metabolismo , Catepsina B/farmacología , Placenta/metabolismo , ARN Interferente Pequeño , Caspasas/metabolismo , Proteínas de Unión al Calcio/metabolismo , Proteínas Adaptadoras de Señalización CARD/metabolismo , Proteínas NLR/metabolismo
2.
Mol Cancer ; 22(1): 200, 2023 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-38066564

RESUMEN

BACKGROUND: Commercial anti-CD19 chimeric antigen receptor T-cell therapies (CART19) are efficacious against advanced B-cell non-Hodgkin lymphoma (NHL); however, most patients ultimately relapse. Several mechanisms contribute to this failure, including CD19-negative escape and CAR T dysfunction. All four commercial CART19 products utilize the FMC63 single-chain variable fragment (scFv) specific to a CD19 membrane-distal epitope and characterized by slow association (on) and dissociation (off) rates. We hypothesized that a novel anti-CD19 scFv that engages an alternative CD19 membrane-proximal epitope independent of FMC63 and that is characterized by faster on- and off-rates could mitigate CART19 failure and improve clinical efficacy. METHODS: We developed an autologous CART19 product with 4-1BB co-stimulation using a novel humanized chicken antibody (h1218). This antibody is specific to a membrane-proximal CD19 epitope and harbors faster on/off rates compared to FMC63. We tested h1218-CART19 in vitro and in vivo using FMC63-CART19-resistant models. We conducted a first-in-human multi-center phase I clinical trial to test AT101 (clinical-grade h1218-CART19) in patients with relapsed or refractory (r/r) NHL. RESULTS: Preclinically, h1218- but not FMC63-CART19 were able to effectively eradicate lymphomas expressing CD19 point mutations (L174V and R163L) or co-expressing FMC63-CAR19 as found in patients relapsing after FMC63-CART19. Furthermore, h1218-CART19 exhibited enhanced killing of B-cell malignancies in vitro and in vivo compared with FMC63-CART19. Mechanistically, we found that h1218-CART19 had reduced activation-induced cell death (AICD) and enhanced expansion compared to FMC63-CART19 owing to faster on- and off-rates. Based on these preclinical results, we performed a phase I dose-escalation trial, testing three dose levels (DL) of AT101 (the GMP version of h1218) using a 3 + 3 design. In 12 treated patients (7 DLBCL, 3 FL, 1 MCL, and 1 MZL), AT101 showed a promising safety profile with 8.3% grade 3 CRS (n = 1) and 8.3% grade 4 ICANS (n = 1). In the whole cohort, the overall response rate was 91.7%, with a complete response rate of 75.0%, which improved to 100% in DL-2 and -3. AT101 expansion correlates with CR and B-cell aplasia. CONCLUSIONS: We developed a novel, safe, and potent CART19 product that recognizes a membrane-proximal domain of CD19 with fast on- and off-rates and showed significant efficacy and promising safety in patients with relapsed B-cell NHL. TRIAL REGISTRATION: NCT05338931; Date: 2022-04-01.


Asunto(s)
Linfoma no Hodgkin , Receptores de Antígenos de Linfocitos T , Receptores Quiméricos de Antígenos , Humanos , Anticuerpos , Antígenos CD19 , Epítopos/metabolismo , Inmunoterapia Adoptiva/efectos adversos , Linfoma no Hodgkin/terapia , Linfoma no Hodgkin/metabolismo , Recurrencia Local de Neoplasia/metabolismo , Receptores Quiméricos de Antígenos/metabolismo , Receptores de Antígenos de Linfocitos T/antagonistas & inhibidores
3.
Eur Arch Otorhinolaryngol ; 280(9): 4121-4129, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37039894

RESUMEN

PURPOSE: Accumulating evidence suggests that Staphylococcus aureus plays a significant role as a disease modifier in upper and lower airway diseases. We aimed to assess the association between staphylococcal enterotoxins (SEs) with allergic diseases and the degree of allergen sensitisation in children, which remains unclear. METHODS: We retrospectively reviewed the medical records of 455 patients aged 3-18 years between March 2018 and March 2022. Clinical history and demographic data were obtained. The baseline study included paranasal sinus X-ray scan, multiple allergen simultaneous test, and ImmunoCAP® for measuring serum total and specific immunoglobulin E (IgE) levels to allergens and staphylococcal enterotoxin A and B (SEA and SEB). RESULTS: The mean age was 9.77 ± 4.3 years. 133 patients (29.2%) were sensitised to one inhalant allergen, and 188 patients (41.3%) showed polysensitisation. Patients sensitised to SEs showed higher total and specific IgE levels and total eosinophil counts compared to non-SE-sensitised patients. Sensitisation to SEs is closely associated with polysensitisation to inhalant allergens and allergic multimorbidity. When the SE-IgE value was 0.35 or higher, the odds ratio for allergen polysensitisation was significantly higher than when the SE-IgE value was lower than 0.35. CONCLUSIONS: Association between polysensitisation and sensitisation to SEs in children shows the higher the specific IgE levels for SEs, the higher the likelihood of polysensitisation. Considering the relationship between polysensitisation, high IgE levels, and the severity of allergic morbidity, sensitisation to SEs is thought to be related to allergy severity.


Asunto(s)
Hipersensibilidad , Humanos , Niño , Preescolar , Adolescente , Estudios Retrospectivos , Alérgenos , Enterotoxinas , Inmunoglobulina E
4.
J Craniofac Surg ; 34(8): 2533-2535, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37643111

RESUMEN

The pterygopalatine fossa is a clinically inaccessible space deep in the face, and reports of pterygopalatine fossa abscesses are rare. The authors present the case of a 63-year-old woman presenting with a severe headache owing to an abscess involving the pterygopalatine fossa. On a computed tomography scan, inflammation of the right pterygopalatine fossa associated with right maxillary sinusitis and periapical inflammation and a cystic lesion around the tooth were observed. After administering appropriate antibiotics, the headache improved considerably, and endoscopic nasal surgery resulted in adequate abscess drainage. To the authors' knowledge, this case study is one of the few reporting the successful treatment of an abscess in the pterygopalatine fossa through an endoscopic transnasal approach.


Asunto(s)
Absceso , Sinusitis Maxilar , Femenino , Humanos , Persona de Mediana Edad , Absceso/diagnóstico por imagen , Absceso/cirugía , Fosa Pterigopalatina/diagnóstico por imagen , Fosa Pterigopalatina/cirugía , Endoscopía/métodos , Sinusitis Maxilar/diagnóstico por imagen , Sinusitis Maxilar/cirugía , Drenaje , Cefalea
5.
Medicina (Kaunas) ; 59(8)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37629722

RESUMEN

Background and Objectives: Limited palatal muscle resection (PMR) is a surgical technique employed to alleviate respiratory disturbances in obstructive sleep apnea (OSA) patients with retropalatal narrowing by reducing soft palate volume and tightening the muscles. Although some previous publications have demonstrated the effectiveness of limited PMR, the overall efficacy and therapeutic role of limited PMR for the treatment of OSA remain uncertain. This study utilized meta-analysis and a systematic literature review to estimate the overall effectiveness of limited PMR in treating OSA. Materials and Methods: Multiple databases, including PubMed, EMBASE, Cochrane Library, and Web of Science, were searched using specific keywords related to OSA and limited PMR. Original articles assessing respiratory disturbances before and after limited PMR in patients with OSA were included. Data from selected articles were collected using standardized forms, including clinicodemographic characteristics, apnea-hypopnea index (AHI), and lowest pulse oximetry values (minimum SpO2). Random effect models were used for analyzing significant heterogeneity. Egger's test and funnel plot were used to identify publication bias. Results: Four studies were included in this meta-analysis for AHI, and three studies were included for minimum SpO2 during sleep. A significant reduction in the AHI and an increase in the minimum SpO2 were shown following limited PMR as the standardized mean difference (95% confidence interval) was 2.591 (1.092-4.090) and 1.217 (0.248-2.186), respectively. No publication bias was found in either analysis. Conclusions: The results of the meta-analysis and systemic review add to the literature that limited PMR can result in a reduction in the AHI and an increase in min SaO2. In OSA patients with suspected retropalatal obstruction, limited PMR may be efficiently performed.


Asunto(s)
Músculos Palatinos , Apnea Obstructiva del Sueño , Humanos , Bases de Datos Factuales , Músculos Palatinos/cirugía , Sueño , Apnea Obstructiva del Sueño/cirugía
6.
Aesthetic Plast Surg ; 46(5): 2428-2437, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34799765

RESUMEN

BACKGROUND: Diced cartilage glue (DG) grafts have been widely used in dorsal augmentation but can induce dorsal irregularities. The authors evaluated the postoperative feasibility of a crushed septal cartilage-covered diced cartilage glue (CCDG) graft. METHODS: The medical records of 38 patients who underwent dorsal augmentation rhinoplasty with an open approach were retrospectively reviewed. DG graft was used in 18 patients (47.4%), and CCDG graft was used in 20 patients (52.6%). Surgical outcomes were assessed by comparing anthropometric data on facial photographs and satisfaction questionnaires on aesthetic outcomes and palpable irregularities on nasal dorsum before and after surgery. RESULTS: Both groups showed successful aesthetic outcomes. Dorsal height, radix height, and tip projection were all increased postoperatively in both groups. Tip rotation did not significantly increase (p > 0.05). Both groups showed similar outcomes in terms of aesthetic satisfaction but a significant difference in palpable irregularity. CCDG graft group showed significantly better (p = 0.04) satisfaction with dorsal irregularities (4.15 ± 0.75) than the DG graft group (3.56 ± 0.92). CCDG graft group also showed significantly better mean values (p = 0.048) in the degree of irregularity by two surgeons (3.85 ± 0.65) than the DG graft group (3.25 ± 0.97). No patient had significant complaints about irregular dorsum, and none of them underwent a revision rhinoplasty. CONCLUSION: CCDG graft can be a complementary option for avoiding postoperative irregular dorsum complications. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266 .


Asunto(s)
Rinoplastia , Humanos , Estudios Retrospectivos , Rinoplastia/métodos , Cartílago/trasplante , Nariz/cirugía , Estética , Complicaciones Posoperatorias/cirugía , Resultado del Tratamiento
7.
Int J Mol Sci ; 23(21)2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36362370

RESUMEN

Sirtuin 1 (SIRT1) regulates cellular processes by deacetylating non-histone targets, including transcription factors and intracellular signalling mediators; thus, its abnormal activation is closely linked to the pathophysiology of several diseases. However, its function in Toxoplasma gondii infection is unclear. We found that SIRT1 contributes to autophagy activation via the AMP-activated protein kinase (AMPK) and PI3K/AKT signalling pathways, promoting anti-Toxoplasma responses. Myeloid-specific Sirt1-/- mice exhibited an increased cyst burden in brain tissue compared to wild-type mice following infection with the avirulent ME49 strain. Consistently, the intracellular survival of T. gondii was markedly increased in Sirt1-deficient bone-marrow-derived macrophages (BMDMs). In contrast, the activation of SIRT1 by resveratrol resulted in not only the induction of autophagy but also a significantly increased anti-Toxoplasma effect. Notably, SIRT1 regulates the FoxO-autophagy axis in several human diseases. Importantly, the T. gondii-induced phosphorylation, acetylation, and cytosolic translocation of FoxO1 was enhanced in Sirt1-deficient BMDMs and the pharmacological inhibition of PI3K/AKT signalling reduced the cytosolic translocation of FoxO1 in BMDMs infected with T. gondii. Further, the CaMKK2-dependent AMPK signalling pathway is responsible for the effect of SIRT1 on the FoxO3a-autophagy axis and for its anti-Toxoplasma activity. Collectively, our findings reveal a previously unappreciated role for SIRT1 in Toxoplasma infection.


Asunto(s)
Toxoplasma , Animales , Humanos , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sirtuina 1/genética , Toxoplasma/metabolismo , Factores de Transcripción Forkhead/metabolismo
8.
J Cell Mol Med ; 25(19): 9460-9472, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34464509

RESUMEN

Fas-associated factor 1 (FAF1) has gained a reputation as a member of the FAS death-inducing signalling complex. However, the role of FAF1 in the immunity response is not fully understood. Here, we report that, in the human retinal pigment epithelial (RPE) cell line ARPE-19 cells, FAF1 expression level was downregulated by Toxoplasma gondii infection, and PI3K/AKT inhibitors reversed T. gondii-induced FAF1 downregulation. In silico analysis for the FAF1 promoter sequence showed the presence of a FOXO response element (FRE), which is a conserved binding site for FOXO1 transcription factor. In accordance with the finding, FOXO1 overexpression potentiated, whereas FOXO1 depletion inhibited intracellular FAF1 expression level. We also found that FAF1 downregulation by T. gondii is correlated with enhanced IRF3 transcription activity. Inhibition of PI3K/AKT pathway with specific inhibitors had no effect on the level of T. gondii-induced IRF3 phosphorylation but blocked IRF3 nuclear import and ISGs transcription. These results suggest that T. gondii can downregulate host FAF1 in PI3K/AKT/FOXO1-dependent manner, and the event is essential for IRF3 nuclear translocation to active the transcription of ISGs and thereby T. gondii proliferation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Reguladoras de la Apoptosis/genética , Regulación de la Expresión Génica , Interacciones Huésped-Parásitos/genética , Factor 3 Regulador del Interferón/metabolismo , Toxoplasma/fisiología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Línea Celular , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Proteína Forkhead Box O1/metabolismo , Humanos , Factor 3 Regulador del Interferón/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Toxoplasmosis/genética , Toxoplasmosis/metabolismo , Toxoplasmosis/parasitología
9.
Korean J Parasitol ; 59(2): 121-129, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33951767

RESUMEN

We aimed to explore the population dynamics of snail in 3 sites of the White Nile in Sudan. More specifically, we aimed to investigate the annual patterns of snail populations that act as intermediate hosts of schistosomes and monthly snail infection rates and ecological characteristics presumably related to snail populations. We collected snails for 1 year monthly at 3 different shore sites in the vicinity of El Shajara along the White Nile river in Khartoum State, Sudan. In addition, we measured air and water temperatures, water turbidities, vegetation coverages, and water depths and current speeds. Most of the collected snails were Biomphalaria pfeifferi and Bulinus truncatus. The population densities of snails and their infection rates varied across survey sites. The collected snails liberated S. mansoni and S. haematobium cercariae as well as Amphistome and Echinostome cercariae. Infected snails were found during March-June. The ecological characteristics found to be associated with the absence of snails population were: high turbidity, deep water, low vegetation coverage (near absence of vegetation), high water temperature, and high current speed. To our knowledge, this is the first longitudinal study of the snail population and ecological characteristics in the main basin of the White Nile river.


Asunto(s)
Biomphalaria/crecimiento & desarrollo , Bulinus/crecimiento & desarrollo , Reservorios de Enfermedades/estadística & datos numéricos , Ríos/parasitología , Animales , Biomphalaria/parasitología , Bulinus/parasitología , Reservorios de Enfermedades/parasitología , Ecosistema , Dinámica Poblacional , Ríos/química , Schistosoma/clasificación , Schistosoma/genética , Schistosoma/aislamiento & purificación , Estaciones del Año , Sudán
10.
J Korean Med Sci ; 35(46): e394, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33258330

RESUMEN

This study compared the anthelminthic effects of three different brands of praziquantel being used in Sudan against Schistosoma haematobium (S. haematobium) infection. We enrolled 1,286 schoolchildren from six primary schools and examined their urine samples for eggs of S. haematobium at the baseline survey and follow-up two weeks after administering the medication. The schoolchildren were divided into three groups based on the three brands of praziquantel (different material production), with two school children for one brand. The overall baseline prevalence of S. haematobium infection was 15.5%. Two weeks after treatment with brands A, B, and C of praziquantel, cure rates were 87.1%, 82.4% and 83.8% respectively, and the egg-reduction rates were 69.0%, 81.0% and 70.6% respectively. There was no statistically significant difference in cure rates and egg-reduction rates between the three brands. We conclude that the three different commercial brands of praziquantel used in Sudan have similar anthelminthic effects on S. haematobium.


Asunto(s)
Antihelmínticos/uso terapéutico , Praziquantel/uso terapéutico , Esquistosomiasis Urinaria/tratamiento farmacológico , Animales , Antihelmínticos/química , Antihelmínticos/farmacología , Niño , Femenino , Humanos , Masculino , Óvulo/efectos de los fármacos , Praziquantel/química , Praziquantel/farmacología , Schistosoma haematobium/efectos de los fármacos , Schistosoma haematobium/crecimiento & desarrollo , Schistosoma haematobium/aislamiento & purificación , Instituciones Académicas , Sudán , Resultado del Tratamiento
11.
Korean J Parasitol ; 58(3): 237-247, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32615737

RESUMEN

Dendritic cell is one of the first innate immune cell to encounter T. gondii after the parasite crosses the host intestinal epithelium. T. gondii requires intact DC as a carrier to infiltrate into host central nervous system (CNS) without being detected or eliminated by host defense system. The mechanism by which T. gondii avoids innate immune defense of host cell, especially in the dendritic cell is unknown. Therefore, we examined the role of host PI3K/AKT signaling pathway activation by T. gondii in dendritic cell. T. gondii infection or T. gondii excretory/secretory antigen (TgESA) treatment to the murine dendritic cell line DC2.4 induced AKT phosphorylation, and treatment of PI3K inhibitors effectively suppressed the T. gondii proliferation but had no effect on infection rate or invasion rate. Furthermore, it is found that T. gondii or TgESA can reduce H2O2-induced intracellular reactive oxygen species (ROS) as well as host endogenous ROS via PI3K/AKT pathway activation. While searching for the main source of the ROS, we found that NADPH oxidase 4 (NOX4) expression was controlled by T. gondii infection or TgESA treatment, which is in correlation with previous observation of the ROS reduction by identical treatments. These findings suggest that the manipulation of the host PI3K/AKT signaling pathway and NOX4 expression is an essential mechanism for the down-regulation of ROS, and therefore, for the survival and the proliferation of T. gondii.


Asunto(s)
Células Dendríticas/metabolismo , Interacciones Huésped-Parásitos , NADPH Oxidasa 4/fisiología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/fisiología , Toxoplasma/fisiología , Animales , Línea Celular , Regulación hacia Abajo , Humanos , Ratones
12.
Korean J Parasitol ; 58(4): 421-430, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32871636

RESUMEN

This study aimed to investigate whether mass drug administration (MDA) intervention has an equivalent effect on reducing the prevalence and intensity of Schistosoma haematobium infection regardless of the baseline values. A repeated cross-sectional survey was performed targeting students of 12 primary schools in Al Jabalain and El Salam districts of White Nile State, Sudan, at both 1 week before and 8 months after the MDA. Prior to the baseline survey, school-aged children in Al Jabalain had received MDA interventions twice in 4 years, while those in El Salam had not. The baseline prevalence was 9.1% in Al Jabalain and 35.2% in El Salam, which were reduced to 1.8% and 5.5% at 8 months after the MDA, respectively. The corresponding reduction rates were 80.3% and 84.4%, not significant difference between both districts. However, changes in the geometric mean intensity (GMI) of egg counts were significantly different between both districts. The baseline GMIs were 14.5 eggs per 10 ml of urine (EP10) in Al Jabalain and 18.5 EP10 in El Salam, which were reduced to 7.1 and 11.2 EP10 after treatment, respectively. The corresponding reduction rates were 51.0% and 39.5%. In conclusion, MDA interventions were found to bring about similar relative reduction in prevalence regardless of the baseline value; however, the relative reduction in infection intensity was more salient in the district with a low baseline value for both prevalence and intensity. This clearly points to the importance of repeated MDA interventions in endemic areas, which will eventually contribute to schistosomiasis elimination.


Asunto(s)
Antihelmínticos/administración & dosificación , Administración Masiva de Medicamentos , Esquistosomiasis Urinaria/epidemiología , Esquistosomiasis Urinaria/prevención & control , Adolescente , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Instituciones Académicas , Sudán/epidemiología , Encuestas y Cuestionarios
13.
Korean J Parasitol ; 58(1): 7-14, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32145722

RESUMEN

Toxoplasma gondii is an intracellular protozoan parasite that infects approximately one third of the human popu- lation worldwide. Considering the toxicity and side effects of anti-toxoplasma medications, it is important to develop effec- tive drug alternatives with fewer and less severe off-target effects. In this study, we found that 4-hydroxybenzaldehyde (4- HBA) induced autophagy and the expression of NAD-dependent protein deacetylase sirtuin-1 (SIRT1) in primary murine bone marrow-derived macrophages (BMDMs). Interestingly, treatment of BMDMs with 4-HBA significantly reduced the number of macrophages infected with T. gondii and the proliferation of T. gondii in infected cells. This effect was impaired by pretreating the macrophages with 3-methyladenine or wortmannin (selective autophagy inhibitors) or with sirtinol or EX527 (SIRT1 inhibitors). Moreover, we found that pharmacological inhibition of SIRT1 prevented 4-HBA-mediated expres- sion of LC3-phosphatidylethanolamine conjugate (LC3-II) and the colocalization of T. gondii parasitophorous vacuoles with autophagosomes in BMDMs. These data suggest that 4-HBA promotes antiparasitic host responses by activating SIRT1- mediated autophagy, and 4-HBA might be a promising therapeutic alternative for the treatment of toxoplasmosis.


Asunto(s)
Autofagia , Benzaldehídos/farmacología , Macrófagos/fisiología , Sirtuina 1 , Toxoplasma/crecimiento & desarrollo , Animales , Células Cultivadas , Depresión Química , Ratones Endogámicos C57BL
14.
Korean J Parasitol ; 57(2): 135-144, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31104405

RESUMEN

There have been some reports on schistosomiasis of school children in Sudan's Nile River basin area; however, information about the infection status of Schistosoma species and intestinal helminths among village residents of this area is very limited. Urine and stool samples were collected from the 1,138 residents of the Al Hidaib and Khour Ajwal villages of White Nile State, Sudan in 2014. The prevalence of overall schistosomiasis and intestinal helminthiasis was 36.3% and 7.7%, respectively. Egg positive rates were 35.6% for Schistosoma haematobium, 2.6% for S. mansoni, and 1.4% were mixed. The prevalence of schistosomiasis was significantly higher in men (45.6%) than in women (32.0%), in Khou Ajwal villagers (39.4%) than in Al Hidaib villagers (19.2%), and for age groups ≤15 years old (51.5%) than for age groups >15 years old (13.2%). The average number of eggs per 10 ml urine (EP10) of S. haematobium infections was 18.9, with 22.2 eggs in men vs 17.0 in women and 20.4 in Khou Ajwal villagers vs 8.1 in Al Hidaib villagers. In addition to S. mansoni eggs, 4 different species of intestinal helminths were found in the stool, including Hymenolepis nana (6.6%) and H. diminuta (1.0%). Collectively, urinary schistosomiasis is still prevalent among village residents in Sudan's White Nile River basin and was especially high in men, children ≤15 years, and in the village without a clean water system. H. nana was the most frequently detected intestinal helminths in the 2 villages.


Asunto(s)
Helmintiasis/epidemiología , Parasitosis Intestinales/epidemiología , Esquistosomiasis/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Coinfección/epidemiología , Coinfección/parasitología , Estudios Epidemiológicos , Heces/parasitología , Femenino , Helmintiasis/parasitología , Humanos , Hymenolepis diminuta/aislamiento & purificación , Hymenolepis nana/aislamiento & purificación , Lactante , Recién Nacido , Parasitosis Intestinales/parasitología , Masculino , Persona de Mediana Edad , Recuento de Huevos de Parásitos , Prevalencia , Población Rural , Schistosoma haematobium/aislamiento & purificación , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis/parasitología , Factores Sexuales , Sudán/epidemiología , Orina/parasitología , Adulto Joven
15.
Korean J Parasitol ; 57(2): 83-92, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31104400

RESUMEN

Based on the reactive oxygen species (ROS) regulatory properties of diphenyleneiodonium (DPI), we investigated the effects of DPI on host-infected T. gondii proliferation and determined specific concentration that inhibit the intracellular parasite growth but without severe toxic effect on human retinal pigment epithelial (ARPE-19) cells. As a result, it is observed that host superoxide, mitochondria superoxide and H2O2 levels can be increased by DPI, significantly, followed by suppression of T. gondii infection and proliferation. The involvement of ROS in anti-parasitic effect of DPI was confirmed by finding that DPI effect on T. gondii can be reversed by ROS scavengers, N-acetyl-L-cysteine and ascorbic acid. These results suggest that, in ARPE-19 cell, DPI can enhance host ROS generation to prevent T. gondii growth. Our study showed DPI is capable of suppressing T. gondii growth in host cells while minimizing the un-favorite side-effect to host cell. These results imply that DPI as a promising candidate material for novel drug development that can ameliorate toxoplasmosis based on ROS regulation.


Asunto(s)
Antiprotozoarios/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/parasitología , Factores Inmunológicos/farmacología , Compuestos Onio/farmacología , Especies Reactivas de Oxígeno/metabolismo , Toxoplasma/crecimiento & desarrollo , Antiprotozoarios/toxicidad , Línea Celular , Células Epiteliales/fisiología , Humanos , Factores Inmunológicos/toxicidad , Compuestos Onio/toxicidad , Epitelio Pigmentado de la Retina/efectos de los fármacos , Epitelio Pigmentado de la Retina/parasitología , Toxoplasma/efectos de los fármacos
16.
Parasitol Res ; 117(8): 2597-2605, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29858945

RESUMEN

The conversion of tachyzoites into bradyzoites is a way for Toxoplasma gondii to establish a chronic and asymptomatic infection and achieve lifelong persistence in the host. The bradyzoites form tissue cysts in the retina, but not much is known about the horizontal distribution of the cysts or their interactions with glial cells in the retina. A chronic ocular toxoplasmosis model was induced by per oral administration of T. gondii Me49 strain cysts to BALB/c mice. Two months after the infection, retinas were flat-mounted and immunostained to detect cysts, ganglion cells, Müller cells, astrocytes, and microglial cells, followed by observation under fluorescence and confocal microscope. The horizontal distribution showed a rather clustered pattern, but the clusters were not restricted to certain location of the retina. Axial distribution was confined to the inner retina, mostly in ganglion cell layer or the inner plexiform layer. Both ganglion cells, a type of retinal neurons, and Müller cells, predominant retinal glial cells, could harbor cysts. The cysts were spatially separated from astrocytes, the most abundant glial cells in the ganglion cell layer, while close spatial distribution of microglial cells was observed in two thirds of retinal cysts. In this study, we demonstrated that the retinal cysts were not evenly distributed horizontally and were confined to the inner retina axially. Both neurons and one type of glial cells could harbor cysts, and topographic analysis of other glial cells suggests role of microglial cells in chronic ocular toxoplasmosis.


Asunto(s)
Toxoplasma/fisiología , Toxoplasmosis Ocular/parasitología , Animales , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Microglía/parasitología , Neuroglía/parasitología , Neuronas/parasitología , Retina/parasitología
17.
J Korean Med Sci ; 33(33): e238, 2018 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-30093850

RESUMEN

BACKGROUND: Schistosoma haematobium which causes urogenital schistosomiasis (UGS) is highly prevalent in African countries. Urine microscopy (UM) is the first-line diagnostic method of UGS. Enzyme-linked immunosorbent assay (ELISA) is a common method for screening many parasite infections primarily or alternatively. The present study established an in-house diagnostic system by ELISA and evaluated its diagnostic efficacy in comparison with UM for screening UGS in White Nile State, Republic of Sudan, 2011-2013. METHODS: A total of 490 participants were screened by UM or ELISA, and 149 by both. The in-house ELISA system was established employing soluble egg antigen of S. haematobium and the cut-off absorbance was set at 0.270. RESULTS: Of the 149 subjects, 58 participants (38.9%) were positive by UM, 119 (79.9%) were positive by ELISA and 82 (55.0%) showed consistently positive or negative results by both methods. The diagnostic sensitivity of ELISA was 94.8% and specificity was 29.7% based on UM results. The ELISA positive serum samples also cross-reacted with egg antigens of Schistosoma mansoni and Schistosoma japonicum. CONCLUSION: We have established in-house ELISA for screening serum immunoglobulin (Ig) G antibodies by employing soluble egg antigen of S. haematobium for diagnosis of UGS with 94.8% sensitivity and 29.7% specificity. The ELISA system can supplement the conventional diagnosis by UM.


Asunto(s)
Schistosoma haematobium , Adolescente , Animales , Antígenos Helmínticos , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Microscopía , Esquistosomiasis Urinaria , Esquistosomiasis mansoni , Urinálisis
18.
Korean J Parasitol ; 56(2): 135-145, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29742868

RESUMEN

Due to the critical location and physiological activities of the retinal pigment epithelial (RPE) cell, it is constantly subjected to contact with various infectious agents and inflammatory mediators. However, little is known about the signaling events in RPE involved in Toxoplasma gondii infection and development. The aim of the study is to screen the host mRNA transcriptional change of 3 inflammation-related gene categories, PI3K/Akt pathway regulatory components, blood vessel development factors and ROS regulators, to prove that PI3K/Akt or mTOR signaling pathway play an essential role in regulating the selected inflammation-related genes. The selected genes include PH domain and leucine- rich-repeat protein phosphatases (PHLPP), casein kinase2 (CK2), vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), glutamate-cysteine ligase (GCL), glutathione S-transferase (GST), and NAD(P)H: quinone oxidoreductase (NQO1). Using reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), we found that T. gondii up-regulates PHLPP2, CK2ß, VEGF, GCL, GST, and NQO1 gene expression levels, but down-regulates PHLPP1 and PEDF mRNA transcription levels. PI3K inhibition and mTOR inhibition by specific inhibitors showed that most of these host gene expression patterns were due to activation of PI3K/Akt or mTOR pathways with some exceptional cases. Taken together, our results reveal a new molecular mechanism of these gene expression change dependent on PI3K/Akt or mTOR pathways and highlight more systematical insight of how an intracellular T. gondii can manipulate host genes to avoid host defense.


Asunto(s)
Expresión Génica , Interacciones Huésped-Parásitos/genética , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Epitelio Pigmentado de la Retina/parasitología , Transducción de Señal , Serina-Treonina Quinasas TOR , Toxoplasma/patogenicidad , Toxoplasmosis/genética , Toxoplasmosis/parasitología , Animales , Células Cultivadas , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa
19.
Korean J Parasitol ; 56(3): 301-304, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29996636

RESUMEN

Rodents are important reservoirs of diseases affecting people and livestock, and are major sources of parasite contamination of agricultural products. We surveyed the infection status of intestinal helminths in 2 species of field mice, Apodemus agrarius and A. peninsulae, captured in the agricultural fields of Gangwon-do and Chungcheongnam-do, Korea. Total 83 mice (57 A. agrarius and 26 A. peninsulae) were collected in 2 surveyed areas, and the intestines of each mouse were opened with scissors, and then intestinal contents were examined with microscope. Total 6 species of intestinal helminth were detected in 61 (73.5%) out of 83 mice examined. Four species of nematode, i.e., Nippostrongylus brasiliensis, Aspiculuris tetraptera, Heterakis spp. and ascarid, were found in 40 (48.2%), 14 (16.9%), 11 (13.3%) and 13 (15.7%) mice respectively. One species of cestode, Hymenolepis diminuta and 1 unidentified egg were also detected in the intestines of 14 (16.9%) and 1 (1.2%) mice, respectively. Conclusively, this study identified 5 helminth species in the gastrointestinal tracts of wild rodents captured in some areas in central and northern Korea, and N. brasiliensis was the most prevalent (dominant) species rather than zoonotic ones.


Asunto(s)
Animales Salvajes/parasitología , Helmintos/aislamiento & purificación , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Murinae/parasitología , Nematodos/aislamiento & purificación , Enfermedades de los Roedores/epidemiología , Enfermedades de los Roedores/parasitología , Animales , Cestodos/aislamiento & purificación , Intestinos/parasitología , Ratones , República de Corea/epidemiología
20.
Korean J Parasitol ; 56(4): 325-334, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30196664

RESUMEN

Toxoplasma gondii is an apicomplexan zoonotic protozoan parasite that infects most species of warm-blooded animals, including humans. The heavy incidence and severe or lethal damage caused by T. gondii infection clearly indicate a need for the development of an effective vaccine. T. gondii GRA8 is a member of the dense granules protein family and is used as a marker of acute infection. In the present study, we evaluated the protective immunity induced by DNA vaccination based on a recombinant eukaryotic plasmid, pDsRed2-GRA8, against acute toxoplasmosis in mice. BALB/c mice were intramuscularly immunized with the pDsRed2-GRA8 plasmid and then challenged by infection with the highly virulent GFP-RH strain of T. gondii. The specific immune responses and protective efficacy against T. gondii of this vaccine were analyzed by measuring cytokine and serum antibody titers, splenocyte proliferation assays, and the survival times of mice after challenge. Our results showed that mice immunized with pDsRed2-GRA8 demonstrated specific humoral and cellular responses, induced higher IgG antibody titers with predominant IgG2a production; increased levels of IL-10, IL-12 (p70), IFN-γ, TNF-α, and splenocyte proliferation; and prolonged survival times compared to those of control mice. The present study showed that DNA immunization with pDsRed2-GRA8 induced humoral and cellular immune responses, and all immunized mice showed greater Th1-type immune responses and longer survival times than those of control mice. These results indicated that T. gondii GRA8 DNA immunization induces a partial protective effect against acute toxoplasmosis.


Asunto(s)
Antígenos de Protozoos/genética , Antígenos de Protozoos/inmunología , Proteínas Protozoarias/genética , Proteínas Protozoarias/inmunología , Vacunas Antiprotozoos/inmunología , Toxoplasma/inmunología , Toxoplasmosis/inmunología , Toxoplasmosis/prevención & control , Vacunas de ADN/inmunología , Enfermedad Aguda , Animales , Anticuerpos Antiprotozoarios/sangre , Proliferación Celular , Citocinas/sangre , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunidad Celular , Inmunidad Humoral , Inmunoglobulina G/sangre , Ratones Endogámicos BALB C , Bazo/citología , Bazo/inmunología
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