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1.
Nature ; 574(7778): 353-358, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31619795

RESUMEN

Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2-to end preventable child deaths by 2030-we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000-2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations.


Asunto(s)
Mortalidad del Niño/tendencias , Mortalidad Infantil/tendencias , Niño , Geografía , Salud Global , Humanos , Lactante , Recién Nacido , Objetivos Organizacionales , Salud Pública , Factores Socioeconómicos , Naciones Unidas
2.
BMC Infect Dis ; 24(1): 42, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172676

RESUMEN

BACKGROUND: Toxoplasmosis is a serious or life-threatening disease in immunosuppressed patients and pregnant women. This study examined the likely association between Toxoplasma gondii infection and COVID-19 patients with moderate illness. METHODS: Seventy blood samples were collected from patients at the Health Reference Laboratory of Tabriz, Northwest Iran from April 2021 to September 2021. In addition, 70 healthy subjects of the same age (37 ± 15 years) and sex distribution were ethnically matched. Sera samples were examined for the detection of anti-Toxoplasma antibodies using ELISA. Nested-PCR targets were amplified based on the B1 and GRA6 genes. GRA6 amplicons were subjected to sequencing and phylogenetic analysis. RESULTS: The seroprevalence of toxoplasmosis based on IgG titer was 35.7% in the COVID­19 patients and 27.1% in the control group, representing not to be associated with the Toxoplasma seropositivity in COVID­19 patients (P = 0.18) compared to healthy subjects. Anti-T. gondii IgM was not found in any of the patients and healthy individuals. According to PCR amplification of the B1 and GRA6 genes, the frequency of T. gondii in COVID-19 patients was 14.2% (10/70). However, no T. gondii infection was detected in the healthy group. The CD4+T cell count was relatively lower in toxoplasmosis-infected patients (430-450 cells/mm3) than in control group (500-1500 cells/mm3). High genetic diversity (Hd: 0.710) of the type I strain of T. gondii was characterized in the patients. Present results showed that consumption of raw vegetables and close contact with stray cats can increase the transmission of T. gondii to COVID-19 patients (P < 0.01). CONCLUSIONS: The current study revealed that T. gondii type I infection is unequivocally circulating among the COVID-19 patients in Tabriz; However, no significant association was observed between the occurrence of Toxoplasma and the severity of COVID-19. To make more accurate health decisions, multicenter investigations with a larger sample size of different ethnic groups of the Iranian population are needed.


Asunto(s)
COVID-19 , Toxoplasma , Toxoplasmosis , Humanos , Femenino , Embarazo , Gatos , Animales , Adulto Joven , Adulto , Persona de Mediana Edad , Toxoplasma/genética , Irán/epidemiología , Estudios Seroepidemiológicos , Estudios de Casos y Controles , Filogenia , Anticuerpos Antiprotozoarios , COVID-19/epidemiología , Toxoplasmosis/diagnóstico , Variación Genética , Inmunoglobulina M , Factores de Riesgo
3.
Microb Pathog ; 181: 106179, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37245631

RESUMEN

The genetic variability of apicomplexan parasite Babesia species is a principal strategy used by piroplasma to evade their hosts' immune responses. The purpose of this review was to evaluate our current knowledge on global haplotype distribution and phylogeography of Babesia ovis derived from sheep, goat, horse and ixodid (hard) ticks. Bibliographic English databases were searched from 2017 to 2023, identifying a total of 11 publications. The 18S ribosomal RNA (18S rRNA) sequences of B. ovis from Asia, Europe, and Africa were retrieved and subjected to estimate the genetic diversity and phylogenetic assessment. A haplotype network indicated a total of 29 haplotypes being classified into two distinct geographical haplogroups I and II including Nigeria and Uganda-derived B. ovis isolates. A moderately high level of genetic diversity was characterized in sheep/tick-derived B. ovis isolates originating from Iraq (Haplotype diversity: 0.781) and Turkey (Hd: 0.841). Based on the cladistic phylogenetic tree, two geographically different lineages of A and B were genetically differentiated except for Turkish isolates, indicating haplotype migration occurred between various geographical clades. In addition, the topology of UPGMA tree indicated that B. ovis population has a distinct clade compared to the rest clades of ovine babesiosis (B. crassa and B. motasi). The present results strengthen our knowledge to evaluate the evolutionary paradigms and transmission dynamics of B. ovis in different regions of the world; also it will provide groundwork for public health policy to control ovine babesiosis.


Asunto(s)
Babesia , Babesiosis , Ixodidae , Enfermedades de las Ovejas , Animales , Babesia/genética , Babesiosis/epidemiología , Babesiosis/parasitología , Cabras , Haplotipos , Caballos , Nigeria , Filogenia , Filogeografía , ARN Ribosómico 18S/genética , Ovinos , Enfermedades de las Ovejas/epidemiología
4.
Parasitol Res ; 122(1): 177-184, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36369362

RESUMEN

Congenital toxoplasmosis can cause severe consequences in the fetus, such as spontaneous abortion which is affected by parasite strain. Also, recent studies revealed the high genetic diversity of Toxoplasma gondii. This study aims to investigate the serological status of T. gondii in pregnant women, multilocus genotyping in aborted fetuses' tissue, and archived formalin-fixed paraffin-embedded placenta. This study was performed on 100 pregnant women with spontaneous abortion and their aborted fetuses, and 250 of the archived placentae in Iran. The blood and tissue were examined for seroprevalence and genotype determination of T. gondii using ELISA and multilocus nested-PCR-RFLP, respectively. Anti-T. gondii IgG and IgM were detected in 68 samples (68%) and 1 (1%) out of 100 serums. Toxoplasma DNA was identified in 1 (1%) aborted fetuses' tissue and 32 (12.8%) placenta samples. Overall, ten positive DNA samples were successfully genotyped, and five genotypes were recognized (ToxoDB#1, #2, #10, #27, and #48). The obtained results indicated congenital toxoplasmosis is a severe risk in this region. As type I is highly pathogen and can lead to severe complications, the prevention of the infection should be considered in seronegative pregnant women.


Asunto(s)
Aborto Espontáneo , Toxoplasma , Toxoplasmosis Animal , Toxoplasmosis Congénita , Humanos , Femenino , Embarazo , Animales , Toxoplasma/genética , Toxoplasmosis Congénita/epidemiología , Irán/epidemiología , Genotipo , Estudios Seroepidemiológicos , Anticuerpos Antiprotozoarios , Toxoplasmosis Animal/parasitología
5.
Exp Parasitol ; 243: 108428, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36384195

RESUMEN

BACKGROUND: Cystic echinococcosis (CE), a widespread helminthic disease caused by the larval stage of the dog tapeworm Echinococcus granulosus represents a public health concern in humans. Albendazole (ABZ) is the first-line treatment for CE; however therapeutic failure of ABZ against CE occurs because of size and location of formed cysts as well its low aqueous solubility and consequently its erratic bioavailability in plasma. Serious adverse effects have also been observed following the long-term use of ABZ in vivo. METHODS: We evaluated the apoptotic effects of ABZ-loaded ß-cyclodextrin (ABZ-ß-CD) against protoscoleces (PSCs) versus ABZ alone. After 15 h of exposure, Caspase-3 enzymatic activity was determined by fluorometric assay in PSCs treated with ABZ and ABZ-ß-CD groups. To assess the treatment efficacy of ABZ-ß-CD against PSCs, mRNA expression of Arginase (EgArg) and Thioredoxin peroxidase (EgTPx) were quantified by Real-time PCR. RESULTS: A significant scolicidal activity of ABZ was observed only at a concentration of 800 µg/mL (100% PSCs mortality rate after 4 days of exposure), while the 200 and 400 µg/mL ABZ reached 100% PSCs mortality rate after 9 sequential days. The 400 µg/mL ABZ-ß-CD had 100% scolicidal rate after 5 days of exposure. Morphological alterations using scanning electron microscopy in treated PSCs revealed that 400 µg/mL ABZ-ß-CD induced higher Caspase-3 activity than their controls, indicating a more potent apoptotic outcome on the PSCs. Also, we showed that the 400 µg/mL ABZ-ß-CD can down-regulate the mRNA expression of EgArg and EgTPx, indicating more potent interference with growth and antioxidant properties of PSCs. CONCLUSIONS: In the present study, a significant scolicidal rate, apoptosis intensity and treatment efficacy was observed in PSCs treated with 400 µg/mL ABZ-ß-CD compared to ABZ alone. This provides new insights into the use of nanostructured ß-CD carriers with ABZ as a promising candidate to improve the treatment of CE in in vivo models.


Asunto(s)
Equinococosis , Echinococcus granulosus , beta-Ciclodextrinas , Animales , Perros , Humanos , Albendazol/farmacología , Caspasa 3 , Equinococosis/tratamiento farmacológico , beta-Ciclodextrinas/farmacología , ARN Mensajero
6.
Microb Pathog ; 157: 104962, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34022359

RESUMEN

Cystic echinococcosis, an important zoonotic disease, is caused by Echinococcus granulosus. MicroRNAs are a small group of single-stranded noncoding RNAs, which play an effective role in biological processes. This study aimed at comparing the expression levels of miR-146a and miR-155 in the plasma of patients with hydatidosis and healthy individuals. A group of 20 patients with hydatid cyst formed a study group and 20 healthy individuals with no known chronic diseases formed a control group. Plasma samples were collected from hydatidosis patients as well as sex- and age-matched healthy volunteers. After that, RNA extraction and cDNA synthesis were done and the expression levels of miR-146a and miR-155 were determined by quantitative real-time polymerase chain reaction (PCR) for both groups. The results indicated that the level of miR-146a increased in all patients with hydatidosis compared to the control group. Also, the level of miR-155 increased in all hydatidosis patients, but no correlation was observed in the level of miR-155 between the two groups. The results also revealed that miR-146a and miR-155 upregulation in the plasma leads to the development of novel biomarkers for echinococcosis. One of the reasons for the increase of miRNAs in hydatidosis may be their role in modulating the immune system. These miRNAs are likely to be considered as one of the most important biomarkers in determining the severity of hydatidosis.


Asunto(s)
Equinococosis , MicroARNs , Animales , Biomarcadores , Equinococosis/diagnóstico , Equinococosis/inmunología , Humanos , Inmunidad , MicroARNs/sangre
7.
Microb Pathog ; 153: 104804, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33609644

RESUMEN

Hydatid cyst fluid (HCF)-based therapeutics has experimentally targeted approaches for treating human cancer cell lines. MicroRNA-365 (miR-365) has been reported to be an important tumor suppressor miRNA in cancers. However, it remains unknown, how miR-365 plays a pivotal role in inducing apoptosis in HCF-treated cancer cells in vitro. The fertile/infertile HCF was aspirated from liver of infected sheep and in terms of molecular taxonomy was identified as G1 genotype of Echinococcus granulosus sensu stricto. A375 human melanoma cancer cells were cultured into two groups: fertile and infertile HCF-treated A375 cells. To assess the cytotoxicity of various concentrations of HCF on melanoma cells, cell viability was determined by using MTT assay. The IC50 value of HCF on A375 cells was determined 85 µg/mL. Caspase-3 enzymatic activity was evaluated by fluorometric assay in the HCF-treated melanoma cells. In addition, the mRNA expression of Bax, Bcl-2, Caspase-9 and miR-365 were determined by qRT-PCR. Findings of MTT assay showed that concentrations 85 µg/mL to 100 µg/mL of fertile HCF have the highest mortality (50%-52%) on A375 cells during 24 h. The fold change of Bax/Bcl-2 ratio, Caspase-9, miR-365 and Caspase-3 activity was higher in the fertile HCF-treated melanoma cells compared to infertile fluid treated A375 cells and human normal epithelial cell (as control cell). In conclusion, we over-expressed the miR-365 in melanoma A375 cells, via treatment of fertile HCF. Our findings suggested that inducing high expression of miR-365 might be a negative regulator of melanoma growth through activation of pro-apoptotic Bax, Caspase-9 and Caspase-3 that are essential to intrinsic apoptotic pathway. These findings provide new insights into the use of Echinococcus HCF-derived metabolites in the design of drug therapies and in vivo tumor cell vaccine to combat melanoma progression.


Asunto(s)
Equinococosis , Echinococcus granulosus , Echinococcus , Melanoma , MicroARNs , Animales , Apoptosis , Línea Celular Tumoral , Echinococcus granulosus/genética , Humanos , Melanoma/genética , MicroARNs/genética , Ovinos
8.
Parasitol Res ; 120(7): 2303-2309, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34110502

RESUMEN

Toxoplasma gondii is an intracellular protozoan parasite that can remarkably infect, survive, and replicate in almost all mammalian cells and can cause severe neurological and ocular damage in immunocompromised individuals. It is known that Natural Killer cells (NK cells), as a type of cytotoxic lymphocyte, have critical protective roles in innate immunity during the T. gondii infection through releasing interferon gamma (IFN-γ). Interleukin 12 (IL-12) is a pivotal critical cytokine for the generation of IFN-γ-producing NK cells. Several studies have shown cytokines' impact on NK cell activation; and IL-2 has an important role with a potent stimulatory factor for NK cells. In this review, we summarized the mechanism of interleukin-12 production stimulation by T. gondii tachyzoites and discussed several factors affecting this mechanism.


Asunto(s)
Interleucina-12/fisiología , Células Asesinas Naturales/inmunología , Toxoplasma/fisiología , Toxoplasmosis/inmunología , Animales , Humanos , Inmunidad Innata , Huésped Inmunocomprometido , Interferón gamma/inmunología , Interferón gamma/metabolismo , Toxoplasma/inmunología
9.
Microb Pathog ; 149: 104578, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33069795

RESUMEN

Toxoplasma gondii, the etiological agent of toxoplasmosis, can cause serious public health problems. Although Toxoplasma gondii tends more to neurotropic and ocular organs, some existing evidence suggest that this disease might induce serious pathological effects on liver. Hence, this study aimed to evaluate the relationship between chronic liver diseases and toxoplasmosis. Meanwhile, it attempted to assess whether patients with toxoplasmosis are susceptible to chronic liver diseases. To achieve this aim, the published studies related to the subject were systematically searched in five major electronic databases between the January 1, 1950 and October 1, 2019. The meta-analysis was carried out using the StatsDirect statistical software and a p-value less than 0.05 was considered significant for any test. Out of 691 identified studies, 10 studies met our inclusion criteria and entered this systematic review. The pooled prevalence rates of Toxoplasma gondii in patients with liver diseases (35.97%; 95% CI: 28.38-43.93) were higher than those in the control group (18.24%; 95% CI: 13.85-23.09). The meta-analysis indicated that the common Odd Ratio by a random effect model was 2.7 (95% CI: 2.30-3.24), revealing a significant association between chronic liver diseases and anti-Toxoplasma IgG antibody. The results of this systematic review confirmed the positive connection between toxoplasmosis and chronic liver diseases. Nonetheless, more studies are needed to clarify the detailed association between these diseases.


Asunto(s)
Hepatopatías , Toxoplasma , Toxoplasmosis , Anticuerpos Antiprotozoarios , Humanos , Hepatopatías/complicaciones , Hepatopatías/epidemiología , Factores de Riesgo , Estudios Seroepidemiológicos , Toxoplasmosis/complicaciones , Toxoplasmosis/epidemiología
10.
Transfus Apher Sci ; 59(3): 102723, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31948918

RESUMEN

BACKGROUND: Toxoplasmosis is a zoonotic disease in animals and human caused by the intracellular obligatory protozoan named Toxoplasma gondii. The purpose of this study was to evaluate the sero-molecular prevalence and genotyping T. gondii among healthy blood donors in north of Iran. METHODS: In this cross-sectional study, 400 blood donors participated from all Blood Transfusion Organization (BTO) in Mazandaran province during October and November 2014. The blood samples were investigated for seroprevalence, DNA detection and genotyping of T. gondii using ELISA, nested-PCR, and Multilocus nested-PCR-RFLP methods respectively. RESULTS: Among all of blood donors, 294 (73.5 %) and 9 (2.2 %) cases were seropositive for anti-T. gondii IgG and IgM antibodies. T. gondii DNA was detected in 7 samples. Four genotype of T. gondii were identified in blood donors samples (Genotype ToxoDB#1, #2, #10 and #27), which 50 % of T. gondii strains were highly pathogenic. CONCLUSIONS: Taking into account survive T. gondii in blood transfusion bag, the high prevalence of T. gondii and existence of pathogenic genotypes in Iranian blood donors, it seems that T. gondii screening should be performed at the BTO to prevent complications of toxoplasmosis in blood recipients.


Asunto(s)
Donantes de Sangre/estadística & datos numéricos , Toxoplasmosis/sangre , Adolescente , Adulto , Animales , Estudios Transversales , Genotipo , Humanos , Irán , Persona de Mediana Edad , Adulto Joven
11.
Parasitol Res ; 119(10): 3125-3143, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32803332

RESUMEN

Pediculosis by Pediculus humanus capitis is still an important health issue in school-age students worldwide. Although pediculicidal agents effectively kill head lice, the re-infestation rate is still high. This study was conducted to provide a summary of evidence about the prevalence of pediculosis capitis among school-age students worldwide. Different databases including MEDLINE/PubMed, Scopus, and Web of Science were searched for publications related to pediculosis capitis in school-age students from 1977 to 2020. All peer-reviewed original research articles describing pediculosis capitis among school-age students were included. Statistical heterogeneity of the different years among studies was assessed using the standard chi squared and I2 tests. Due to the significant heterogeneity, a random effect model was adopted to estimate the pooled, continent, and gender-specific prevalence of pediculosis. Two hundred and one papers met the inclusion criteria of this review and entered into the meta-analysis including 1,218,351 individuals. Through a random effect model, the prevalence of pediculosis capitis among school students was estimated as 19% (CI 95% = 0.18-0.20%, I2 = 99.89%). The prevalence of pediculosis capitis among boys was 7% (CI 95% = 0.05-0.10) compared to 19% (CI 95% = 0.15-0.24) in girls. The highest prevalence was in Central and South America (33%, CI 95% = 0.22-0.44, I2 = 99.81%) and the lowest was in Europe (5%, CI 95% = 4-6, I2 = 99.28%). Relatively high pediculosis capitis prevalence among school-age students observed in this study emphasizes the need for implementing screening and prophylaxis tailored to the local context.


Asunto(s)
Infestaciones por Piojos/epidemiología , Pediculus/crecimiento & desarrollo , Estudiantes/estadística & datos numéricos , Adolescente , Animales , Niño , Europa (Continente)/epidemiología , Femenino , Humanos , Infestaciones por Piojos/tratamiento farmacológico , Masculino , Tamizaje Masivo , Prevalencia , Salud Pública , Instituciones Académicas , América del Sur/epidemiología
12.
J Cell Physiol ; 234(7): 10782-10788, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30565688

RESUMEN

Toxoplasma gondii, an intracellular parasitic protozoan, is capable of infecting man and all warm-blooded animals. Cell-mediated immunity is vital in mounting protective responses against T. gondii infection. Recent studies have shown that T-helper (Th) 17 responses may play a key role in parasite control. In this current study, we constructed a DNA vaccine encoding T. gondii ROP13 in a pcDNA vector. Groups of BALB/c mice were immunized intramuscularly with pcROP13 or controls and challenged with the RH strain of T. gondii. The results showed that immunization with pcROP13 could elicit an antibody response against T. gondii. The expression of the canonical Th17 cytokines, interleukin (IL)-17 and IL-22, were significantly increased after immunization with pcROP13 compared with control groups ( p < 0.05). Furthermore, vaccination resulted in a significant decrease in parasite load ( p < 0.05). The induction of Th17 related cytokines, using a ROP13 DNA vaccine, against T. gondii should be considered as a potential vaccine approach for the control of toxoplasmosis.


Asunto(s)
Inmunogenicidad Vacunal , Interleucina-17/sangre , Interleucinas/sangre , Proteínas Protozoarias/administración & dosificación , Vacunas Antiprotozoos/administración & dosificación , Células Th17/metabolismo , Toxoplasma/inmunología , Toxoplasmosis/prevención & control , Vacunas de ADN/administración & dosificación , Animales , Anticuerpos Antiprotozoarios/sangre , Modelos Animales de Enfermedad , Femenino , Inmunización , Interleucina-17/genética , Interleucina-17/inmunología , Interleucinas/genética , Interleucinas/inmunología , Ratones Endogámicos BALB C , Carga de Parásitos , Proteínas Protozoarias/genética , Proteínas Protozoarias/inmunología , Vacunas Antiprotozoos/genética , Vacunas Antiprotozoos/inmunología , Células Th17/inmunología , Células Th17/parasitología , Toxoplasma/genética , Toxoplasmosis/sangre , Toxoplasmosis/inmunología , Toxoplasmosis/parasitología , Vacunas de ADN/genética , Vacunas de ADN/inmunología , Interleucina-22
13.
Microb Pathog ; 134: 103601, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31212035

RESUMEN

Toxoplasma gondii, the etiological agent of toxoplasmosis, can cause severe or lethal damages in both animals and man. So, tends to develop a more effective vaccine to prevent this disease is extremely needed and would be so prominent. The novel dense granule antigen 14 (GRA14) has been identified as a potential vaccine candidate against T. gondii infection. The aim of this study was evaluation of protective immunity induced by prime/boost vaccination strategy of GRA14 antigen with calcium phosphate (CaPNs) or Aluminum hydroxide (Alum) nano-adjuvants in BALB/c mice. The finding showed that immunization with the prime-boost strategy using plasmid DNA (pcGRA14) and recombinant protein (rGRA14) with nano-adjuvants significantly elicited levels of specific IgG antibodies and cytokines against T. gondii infection. Given that, there were the high levels of total IgG, IgG2a, IFN-γ in mice of rGRA14-CaPNs and pcGRA14 + rGRA14-CaPNs groups, which indicating a Th-1 type response. While immunization of mice with Alum based rGRA14 and pcGRA14 + rGRA14 elicited specific IgG1 and IL-4 levels, which was confirmed a Th-2 type response. Mice immunized with DNA prime-protein boost vaccine with nano-adjuvants produce more vigorous specific lymphoproliferative responses than mice immunized with other antigen formulations. In addition, the CaPNs-based prime-boost vaccine of pcGRA14 + rGRA14 showed the longest survival time in mice and the lowest parasitic load in their brain tissue compared to the other groups. The results obtained in this study show that the use of GRA14 based DNA prime-protein boost vaccination regime with CaPNs can dramatically enhanced both humoral and cellular immune responses. Therefore, this strategy can provide a promising approach to the development of an effective vaccine against T. gondii infection in the future.


Asunto(s)
Antígenos de Protozoos/inmunología , Inmunización Secundaria/métodos , Proteínas Protozoarias/inmunología , Vacunas Antiprotozoos/inmunología , Proteínas Recombinantes/inmunología , Toxoplasma/inmunología , Toxoplasmosis Animal/prevención & control , Vacunación , Adyuvantes Inmunológicos , Hidróxido de Aluminio , Animales , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/genética , Fosfatos de Calcio , Citocinas/sangre , Modelos Animales de Enfermedad , Femenino , Inmunidad Celular/efectos de los fármacos , Inmunidad Humoral/efectos de los fármacos , Inmunoglobulina G/sangre , Interferón gamma/sangre , Interleucina-4/sangre , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Carga de Parásitos , Proteínas Protozoarias/genética , Vacunas Antiprotozoos/genética , Toxoplasma/genética , Toxoplasmosis Animal/inmunología , Vacunas de ADN/inmunología
14.
Lung ; 197(5): 651-661, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31203380

RESUMEN

BACKGROUND: Microbiological cultures are the mainstay of the diagnosis of tuberculosis (TB). False-positive TB results lead to significant unnecessary therapeutic and economic burden and are frequently caused by laboratory cross-contamination. The aim of this meta-analysis was to quantify the prevalence of laboratory cross-contamination. METHODS: Through a systematic review of five electronic databases, we identified studies reporting rates of laboratory cross-contamination, confirmed by molecular techniques in TB cultures. We evaluated the quality of the identified studies using the National Institute of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies, and conducted a meta-analysis using standard methodology recommended by the Cochrane Collaboration. RESULTS: Based on 31 eligible studies evaluating 29,839 TB cultures, we found that 2% (95% confidence intervals [CI] 1-2%) of all positive TB cultures represent false-positive results secondary to laboratory cross-contamination. More importantly, we evaluated the rate of laboratory cross-contamination in cases where a single-positive TB culture was available in addition to at least one negative TB culture, and we found a rate of 15% (95% CI 6-33%). Moreover, 9.2% (91/990) of all patients with a preliminary diagnosis of TB had false-positive results and received unnecessary and potentially harmful treatments. CONCLUSIONS: Our results highlight a remarkably high prevalence of false-positive TB results as a result of laboratory cross-contamination, especially in single-positive TB cultures, leading to the administration of unnecessary, harmful treatments. The need for the adoption of strict technical standards for mycobacterial cultures cannot be overstated.


Asunto(s)
Técnicas Bacteriológicas , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis/diagnóstico , Reacciones Falso Positivas , Humanos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Tuberculosis/microbiología , Tuberculosis/terapia , Procedimientos Innecesarios
15.
Nanomedicine ; 18: 221-233, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30904586

RESUMEN

Mosquitoes (Diptera; Culicidae) present a major threat to millions of people and animals worldwide, as they act as vectors for various pathogens, especially parasites and viruses. Resistance to insecticides, such as organophosphates and microbial control agents, and insufficient adherence to application guidelines are common reasons for insecticide treatment failure. Therefore, there is an urgent need for exploration of safer, cheaper, and more effective agents, with novel modes of action, to improve mosquito control. Biosynthesized nanoparticles (NPs) have recently been considered as a potential approach for combating vectors of malaria and also as a treatment for malaria. Here, we present current knowledge about the characterization and effectiveness of biogenic NPs against major vectors of malaria, including avian malaria (which may also provide useful insights on vectors of human malaria). This article is the first systematic review of the effects of biosynthesized nanoparticles on both malaria parasites (Plasmodium spp.) and relevant vectors.


Asunto(s)
Biotecnología , Malaria/prevención & control , Nanotecnología , Animales , Bacterias/metabolismo , Humanos , Nanopartículas
16.
Parasitol Res ; 118(9): 2455-2466, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31402401

RESUMEN

Echinococcus granulosus sensu lato and E. multilocularis are the causative agents of life-threatening cystic and alveolar echinococcoses (CE and AE), respectively, which lead to serious public health concerns across the globe. Benzimidazoles (BMZs) are the drugs of choice for the treatment of human CE and AE. Presently, the chemotherapeutic failures of BMZs against CE and AE are caused by their low aqueous solubility, poor absorption, and consequently their erratic bioavailability. Among the BMZ compounds used for CE/AE treatment, albendazole (ABZ) and mebendazole (MBZ) are the only drugs licensed for human use. Nevertheless, the administration of these BMZs for a long period of time leads to undesirable adverse effects. Therefore, there is an urgent need for designing new formulations of BMZs with increased bioavailability. To bridge these therapeutic gaps, nanoparticle enantiomers of ABZ and drug delivery systems based on nanostructured entities currently provide an interesting new formulation of already existing drugs to improve the pharmacokinetic effects of BMZs. This study provides an overview of the tested nanocompounds against E. granulosus and E. multilocularis, including their effective dose, type of nanoparticles (NPs), assay setting, and therapeutic outcomes. This review suggests that BMZ derivatives loaded in NPs can significantly improve the scolicidal and cysticidal activities compared with single BMZ. Moreover, BMZ-loaded polymeric NPs show a tendency to increase mortality rate against protoscoleces and microcysts compared with metallic formulations, nanoemulsions, lipid nanocapsules, solid lipid NPs, liposomes, and nanocrystals. In the future, the use of the newly structured entities, attained by bridging ligands to the modified surface of NPs, as well as the electromagnetically produced nanodrugs could be helpful for developing fine-tuned formulations as an alternative to the already existing drugs against these neglected parasitic infections.


Asunto(s)
Albendazol/uso terapéutico , Antiprotozoarios/uso terapéutico , Equinococosis/tratamiento farmacológico , Echinococcus granulosus/efectos de los fármacos , Echinococcus multilocularis/efectos de los fármacos , Mebendazol/uso terapéutico , Animales , Disponibilidad Biológica , Sistemas de Liberación de Medicamentos , Diseño de Fármacos , Equinococosis/parasitología , Humanos , Lípidos , Nanocápsulas , Nanopartículas/química
17.
Parasitol Res ; 117(6): 1717-1727, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29602972

RESUMEN

The study of pathogenesis mechanisms of larval stages in the Taeniidae has recently focused on host genetic factors, particularly toll-like receptor (TLR) variations. However, the potential role of TLR4 polymorphism in hydatidosis has not yet been sufficiently elucidated in postoperative patients. In this case-control investigation, 80 patients from Iran, including 40 with acute hydatidosis (AH) and 40 with recurrent hydatidosis (RH), and 80 ethnically matched controls were evaluated from February 2015 to February 2017. Hydatidosis patients were confirmed using radiological, immunological, and histopathological examinations. Genotyping of Asp299Gly and Thr399Ile of TLR4 single-nucleotide polymorphisms was determined by restriction fragment length polymorphism, sequencing, and phylogenetic strategies. The heterozygous mutant-type TLR4 Asp299Gly genotype indicated a tendency to be associated with the occurrence of RH (P = 0.060) and conferred a 3-fold risk for susceptibility. There was no difference in genotype frequency of Asp299Gly between patients with AH and healthy controls (P = 0.42; OR, 1.82; 95% CI, 0.11-30.1%). Interestingly, a frequency of the G allele (12%: Gly) was observed to be a risk factor for susceptibility to RH patients (P = 0.050; OR, 7.08; 95% CI, 0.97-51.5%). A relative genetic variability of TLR4 Asp299Gly was found in RH patients (haplotype diversity: 0.700) compared to AH patients and healthy controls (Hd: 0.000). The Asp299Gly genotype was dominantly identified in patients with hepatic hydatid cysts. The TLR4 Thr399Ile codon was not detected except in a patient with a pulmonary hydatid cyst. The current findings enhance our knowledge regarding the TLR4 Asp299Gly polymorphism potentially leading to the development of RH, by skewing the immune system towards a Th2 response. Identification of the Asp299Gly codon may be a diagnostic hallmark in RH patients who have undergone unsuccessful postoperative intervention. However, further studies with a higher case number are needed on ethnic population from various geographic regions, in order to confirm this hypothesis.


Asunto(s)
Equinococosis/parasitología , Equinococosis/terapia , Echinococcus granulosus/aislamiento & purificación , Predisposición Genética a la Enfermedad/genética , Receptor Toll-Like 4/genética , Adulto , Alelos , Animales , Estudios de Casos y Controles , Echinococcus granulosus/genética , Echinococcus granulosus/inmunología , Femenino , Genotipo , Haplotipos/genética , Humanos , Irán , Masculino , Persona de Mediana Edad , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Células Th2/inmunología
18.
Parasitol Res ; 116(8): 2159-2166, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28560572

RESUMEN

Apoptosis of infected host macrophages by Leishmania spp. is mainly addressed as one of the survival mechanisms of the parasite. However, there is no eligible data about whether tumor suppressor p53 could induce the apoptosis of host lymphocytes-treated Leishmania major via the mitochondrial intrinsic pathway. In this study, the amastigotes of L. major obtained from ten cutaneous leishmaniases (CL) patients were separately isolated and cultured in N.N.N and RPMI 1640 media. L. major was definitely confirmed by targeting Cyt b gene following sequencing. Subsequently, 2-3 × 106 lymphocytes obtained from ten healthy individuals were isolated and co-cultured with 1-2 × 106 L. major promastigotes. Following 6 h of exposure time, the enzymatic activity of caspase-3 was determined by fluorometric assay in each L. major-treated lymphocytes and cell control (only lymphocyte). The mRNA expressions of Bax, Bcl-2, p53, and caspase-3 genes were assessed by quantitative real-time-PCR analysis following 6 to 9 h of exposure times. The Bcl-2 mRNA expression in L. major-treated lymphocytes was 100-fold down-regulated relative to cell control. The mRNA expressions of p53 and caspase-3 were over-expressed 1.8- and 3.2-fold up-regulated relative to control lymphocytes, respectively. The Bax/Bcl-2 ratio and caspase-3 activity were higher than the control group (Pv <0.05). The current new findings indicate that the apoptotic effects of L. major-treated host lymphocytes dependent on p53 tumor suppressor via mitochondrial pathway may probably address as an auxiliary survival mechanism of L. major in CL patients. However, here is much work ahead to figure out the multiple functions played by apoptosis in the evasion of L. major.


Asunto(s)
Apoptosis , Caspasa 3/metabolismo , Leishmania major/fisiología , Leishmaniasis Cutánea/parasitología , Linfocitos/parasitología , Proteína p53 Supresora de Tumor/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Adolescente , Adulto , Animales , Apoptosis/efectos de los fármacos , Niño , Activación Enzimática , Femenino , Humanos , Leishmaniasis Cutánea/enzimología , Masculino , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Adulto Joven , Proteína X Asociada a bcl-2/genética
19.
Parasitol Res ; 116(4): 1111-1128, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28110441

RESUMEN

Cryptosporidiosis caused by Cryptosporidium spp. is an important parasitic disease that can be life-threatening for children and immunocompromised patients. This systematic review and meta-analysis was designed to determine the prevalence rate of Cryptosporidium infection and related risk factors among the Iranian general population. We searched electronic databases including Google Scholar, PubMed, Science Direct, Scopus and Proquest for articles in English and SID, Magiran, IranMedex, and IranDoc for articles in Persian. Out of 4816 studies identified in the electronic search, 94 articles were eligible for inclusion in the systematic review and meta-analysis. The prevalence rate of cryptosporidiosis by using the random effect model among children, healthy people, and gastroenteritis and immunocompromised patients in Iran was estimated as 3.65, 2.94, 1.29, and 4.54%, respectively. Findings of a phylogenetic analysis inferred by gp60 and 18S ribosomal RNA markers indicated that most of the infection rate belonged to C. parvum (particularly subtype IIaA15G2R1) and C. hominis among understudied groups. The present study is the first systematic review and meta-analysis providing a comprehensive view of the prevalence of human cryptosporidiosis and its related risk factors in Iran. It seems that the awareness of Cryptosporidium prevalence, risk factors, and disease complications may be required for developing effective strategies to prevent infection.


Asunto(s)
Criptosporidiosis/epidemiología , Gastroenteritis/epidemiología , Gastroenteritis/parasitología , Adyuvantes Inmunológicos , Adolescente , Adulto , Anciano , Animales , Niño , Preescolar , Criptosporidiosis/parasitología , Cryptosporidium/clasificación , Bases de Datos Factuales , Femenino , Humanos , Huésped Inmunocomprometido , Lactante , Recién Nacido , Irán/epidemiología , Masculino , Persona de Mediana Edad , Filogenia , Prevalencia , ARN Ribosómico 18S/genética , Factores de Riesgo , Sialoglicoproteínas/genética , Adulto Joven
20.
Parasitol Res ; 116(2): 609-616, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27909791

RESUMEN

Many recent studies have been conducted to evaluate protective immunity mediated by DNA vaccines against toxoplasmosis. Cocktail DNA vaccines showed better immune responses compared to single vaccines. The objective of the current study was to evaluate the protective efficacy of rhomboid 4 (ROM4) and cocktail DNA vaccines (ROM4 + GRA14) of the Toxoplasma gondii RH strain with or without coated calcium phosphate nanoparticles (CaPNs) as the adjuvant to improve the immunogenicity against the T. gondii RH strain in BALB/c mice. Cocktail DNA vaccines of pcROM4 + pcGRA14 of the T. gondii RH strain were constructed. CaPNs were synthesized and the cocktail DNA vaccine was coated with the adjuvant of CaPNs. Immunogenicity and the protective effects of cocktail DNA vaccines with or without CaPNs against lethal challenge were evaluated in BALB/c mice. pcROM4 and cocktail DNA vaccine coated with CaPNs significantly enhanced cellular and humoral immune responses against Toxoplasma compared to pcROM4 and cocktail DNA vaccine without CaPNs (p < 0.05). These findings indicate that the survival time of immunized mice after challenge with the RH strain of T. gondii was increased compared to that of controls and the DNA vaccine provided significant protection in mice (p < 0.05). The CaPN-based cocktail DNA vaccine of pcROM4 + pcGRA14 showed the longest survival time compared to the other groups. Co-immunization with CaPN-based cocktail DNA vaccine (pcROM4 + pcGRA14) boosted immune responses and increased the protective efficacy against acute toxoplasmosis in BALB/c mice compared to both single gene and bivalent DNA vaccine without nano-adjuvants.


Asunto(s)
Toxoplasma/inmunología , Toxoplasmosis Animal/inmunología , Vacunas de ADN/inmunología , Adyuvantes Inmunológicos/genética , Animales , Anticuerpos Antiprotozoarios/inmunología , Fosfatos de Calcio/química , ADN , Femenino , Humanos , Inmunidad Humoral , Inmunización , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Proteínas Protozoarias/genética , Vacunas Antiprotozoos/inmunología , Toxoplasma/genética , Toxoplasmosis Animal/parasitología , Toxoplasmosis Animal/prevención & control , Vacunación , Vacunas de ADN/administración & dosificación , Vacunas de ADN/genética
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