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1.
Parasitol Int ; 100: 102865, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38341021

RESUMO

In visceral and mucocutaneous leishmaniasis, humoral immune response can reflect disease severity and parasite burden. Cutaneous leishmaniasis (CL) in Sri Lanka is caused by a usually visceralizing parasite, Leishmania donovani. We assessed the parasite burden (relative quantity-RQ) in 190 CL patients using quantitative real-time PCR (qPCR-with primers designed for this study) and smear microscopy, then correlated it with clinical parameters and IgG response. RQ of parasite DNA was determined with human-specific glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as the internal control. The qPCR sensitivity was tested with serially diluted DNA from cultured L. donovani parasites. Smears were assigned a score based on number of parasites per high power field. Data from previous studies were used for comparison and correlation; nested Internal Transcribed Spacer 1 (ITS1) PCR as reference standard (RS) and IgG antibody titers to the Leishmania rKRp42 antigen as the immune response. The qPCR amplified and quantified 86.8% of the samples while demonstrating a fair and significant agreement with ITS1-PCR and microscopy. Parasite burden by qPCR and microscopy were highly correlated (r = 0.76; p = 0.01) but showed no correlation with the IgG response (r = 0.056; p = 0.48). Corresponding mean RQs of IgG titers grouped by percentiles, showed no significant difference (p = 0.93). Mean RQ was higher in early lesions (p = 0.04), decreased with lesion size (p = 0.12) and slightly higher among papules, nodules and wet ulcers (p = 0.72). Our study established qPCR's efficacy in quantifying parasite burden in Sri Lankan CL lesions but no significant correlation was observed between the parasite burden and host IgG response to the Leishmania rKRP42 antigen.


Assuntos
Leishmania donovani , Leishmaniose Cutânea , Parasitos , Animais , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Sri Lanka/epidemiologia , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Leishmania donovani/genética , DNA , Imunoglobulina G
2.
Parasit Vectors ; 16(1): 310, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653518

RESUMO

BACKGROUND: Blood-sucking phlebotomine sand flies are vectors of the protozoan parasites Leishmania spp. Although the intestinal microbiota is involved in a wide range of biological and physiological processes and has the potential to alter vector competence, little is known about the factors that modify the gut microbiota composition of sand flies. As a key step toward addressing this issue, we investigated the impact of host species on the gut bacterial composition in Phlebotomus and Lutzomyia sand flies reared under the same conditions. METHODS: Bacterial 16S rRNA gene amplification and Illumina MiSeq sequencing were used to characterize the overall bacterial composition of three laboratory-reared sandflies: Phlebotomus papatasi, Ph. duboscqi, and Lutzomyia longipalpis. RESULTS: Our results showed that the larvae of the three sand fly species harbored almost the same microbes but had different relative abundances. Adult Ph. papatasi and Ph. duboscqi revealed similar microbiome compositions, which were distinct from that of adult Lu. longipalpis. Furthermore, we showed that Ph. papatasi and Ph. duboscqi are hosts for different bacterial genera. The experiment was repeated twice to improve accuracy and increase reliability of the data, and the same results were obtained even when a distinct composition of the microbiome among the same species was identified probably because of the use of different larvae food batch. CONCLUSIONS: The present study provides key insights into the role of host species in the gut microbial content of different sand fly species reared under the same conditions, which may influence their susceptibility to Leishmania infection.


Assuntos
Microbiota , Phlebotomus , Psychodidae , Animais , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes , Larva
3.
Front Cell Infect Microbiol ; 13: 1162918, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545855

RESUMO

A rare sugar, allose, was reported to inhibit the development of Plasmodium parasites in Anopheles mosquitoes; however, the mechanism remains unknown. The present study addressed the inhibitory mechanism of allose on the development of the Plasmodium parasite by connecting it with bacteria involvement in the midgut. In addition, further inhibitory sugars against Plasmodium infection in mosquitoes were explored. Antibiotic-treated and antibiotic-untreated Anopheles stephensi were fed fructose with or without allose. The mosquitoes were infected with luciferase-expressing Plasmodium berghei, and parasite development was evaluated by luciferase activity. Bacterial composition analysis in gut of their mosquitoes was performed with comprehensive 16S ribosomal RNA sequencing. As the result, allose inhibited the development of oocysts in mosquitoes regardless of prior antibiotic treatment. Microbiome analysis showed that the midgut bacterial composition in mosquitoes before and after blood feeding was not affected by allose. Although allose inhibited transient growth of the midgut microbiota of mosquitoes after blood feeding, neither toxic nor inhibitory effects of allose on the dominant midgut bacteria were observed. Ookinete development in the mosquito midgut was also not affected by allose feeding. Additional 15 sugars including six monosaccharides, four polyols, and five polysaccharides were tested; however, no inhibitory effect against Plasmodium development in mosquitoes was observed. These results indicated that allose inhibits parasite development in midgut stage of the mosquito independently of midgut microbiota. Although further studies are needed, our results suggest that allose may be a useful material for the vector control of malaria as a "transmission-blocking sugar."


Assuntos
Anopheles , Malária , Microbiota , Parasitos , Animais , Anopheles/parasitologia , Açúcares , Mosquitos Vetores , Carboidratos , Plasmodium berghei , Malária/parasitologia , Bactérias
4.
Am J Case Rep ; 23: e937869, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36350797

RESUMO

BACKGROUND Centipede envenomation is usually mild, but a review of the existing literature revealed a more serious course in a small proportion of patients. In fact, necrotizing soft-tissue infections have been reported following centipede stings in a small number of cases and require early diagnosis and treatment because of a high mortality rate. CASE REPORT A 78-year-old man was stung by a centipede on the left abdomen. Treatment with antimicrobial agents was started due to cellulitis, but extensive erythema developed from the left chest to the left buttock. Six days after being stung, he visited our hospital. Necrotizing soft-tissue infection was diagnosed and treated immediately with antibiotics and debridement on the left side of the abdomen and chest. Group A Streptococcus was detected in the fascia. The wound was left partially open and washed daily, resulting in gradual improvement of the wound condition. On hospitalization day 8, the open wound was able to be closed. Antimicrobial therapy was completed on hospitalization day 16. The patient showed good progress. CONCLUSIONS Centipede stings are not rare in tropical and subtropical regions, and most occurrences of centipede envenomation cause only local symptoms. However, we believe that even wounds caused by centipedes should be monitored, given the possibility of subsequent severe infection, as in the present case. In addition, the causative organisms identified in the present patient with necrotizing soft-tissue infection following a centipede sting were commensal bacteria of the skin. Future research is thus needed to clarify the relationship between these causative organisms and centipedes.


Assuntos
Quilópodes , Infecções dos Tecidos Moles , Masculino , Animais , Humanos , Idoso , Infecções dos Tecidos Moles/diagnóstico , Infecções dos Tecidos Moles/terapia , Celulite (Flegmão)/microbiologia , Streptococcus pyogenes , Antibacterianos/uso terapêutico
5.
Acta Trop ; 234: 106602, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35817195

RESUMO

Transcriptome analysis of the salivary gland cDNA library from a phlebotomine sand fly, Lutzomyia ayacuchensis, identified a transcript coding for the PpSP15/SL1 family protein as the second most abundant salivary component. In the present study, a recombinant protein of the PpSP15/SL1 family protein, designated ayaconin, was expressed in Escherichia coli, and its biological activity was characterized. The recombinant ayaconin purified from the soluble fraction of E. coli lysate efficiently inhibited the intrinsic but not extrinsic blood coagulation pathway. When the target of ayaconin was evaluated using fluorescent substrates of coagulation factors, ayaconin inhibited factor XIIa (FXIIa) activity more efficiently in a dose-dependent manner, suggesting that FXII is the primary target of ayaconin. In addition, incubation of ayaconin with FXII prior to activation effectively inhibited FXIIa activity, whereas such inhibition was not observed when ayaconin was mixed after the production of FXIIa, indicating that ayaconin inhibits the activation process of FXII to produce FXIIa, but not the enzymatic activity of FXIIa. Moreover, ayaconin was shown to bind to FXII, suggesting that the binding of ayaconin to FXII is involved in the inhibitory mechanism against FXII activation. These results suggest that ayaconin plays an important role in the blood-sucking of Lu. ayacuchensis.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Escherichia coli/genética , Fator XIIa/metabolismo , Insetos Vetores , Psychodidae/genética
6.
Vet Dermatol ; 33(5): 450-453, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35644532

RESUMO

We report the novel use of cryosurgery to treat cutaneous feline leishmaniosis (FeL) in a domestic cat from mid-western Venezuela. Amastigotes, evident by microscopy in aspirates from the nodular, erythematous nose lesions, were identified as Leishmania mexicana by cytochrome b gene sequence analysis. Lesions resolved completely without relapse after 14 months.


Nous décrivons une nouvelle utilisation de la cryochirurgie pour traiter la leishmaniose féline cutanée (FeL) chez un chat domestique du centre-ouest du Venezuela. Les amastigotes, observés par microscopie dans les cytoponctions des lésions nodulaires et érythémateuses du nez, ont été identifiés comme Leishmania mexicana par analyse de la séquence du gène du cytochrome b. Les lésions ont complètement disparu sans rechute après 14 mois.


Describimos el uso novedoso de la criocirugía para tratar la leishmaniosis cutánea felina (FeL) en un gato doméstico del medio oeste de Venezuela. Los amastigotes, evidentes por microscopía en los aspirados de las lesiones nasales nodulares eritematosas, se identificaron como Leishmania mexicana mediante el análisis de la secuencia del gen del citocromo b. Las lesiones se resolvieron completamente sin recidiva tras 14 meses.


Neste estudo, relatamos a utilização inédita de criocirurgia para tratar leishmaniose felina cutânea (FeL) em um gato doméstico no centro-oeste da Venezuela. Amastigotas, evidentes à microscopia de aspirados da lesão nodular e eritematosa na região nasal, foram identificadas como Leishmania Mexicana por sequenciamento do gene do citocromo b. As lesões se resolveram completamente sem recidiva após 14 meses.


Assuntos
Doenças do Gato , Leishmania mexicana , Leishmaniose Cutânea , Animais , Doenças do Gato/cirurgia , Gatos , Crioterapia/veterinária , Leishmaniose Cutânea/terapia , Leishmaniose Cutânea/veterinária
7.
Microorganisms ; 10(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35630365

RESUMO

Clinical diagnosis has become a challenge amidst a surge of cutaneous leishmaniasis in Southern Sri Lanka. The routine diagnostic method, slit-skin smear (SSS), has variable sensitivity, leading to undiagnosed cases. Improved diagnostics are urgently needed. We assessed a new in-house ELISA method for its diagnostic capabilities against ITS-1 nested PCR (gold standard­Gs). A cohort of 190 clinical CL cases was examined by SSS microscopy, anti-rKRP42 IgG ELISA (serum- and urine-based), and rK39-Immunochromatographic strip test. Validation was done using non-endemic sera, and cutoffs were developed using the receiver operating curve. The sensitivity of SSS for case detection was 77.9% (authors) and 76.3% (technicians). ELISA vs. Gs demonstrated sensitivity (Sn) = 94.4%; specificity (Sp) = 50.0%; positive predictive value (PPV) = 97.1%; negative predictive value (NPV) = 33.3%; Kappa agreement (Kp) = 0.39/p < 0.01. Comparison of the combination method (SSS by technicians and ELISA) vs. Gs showed: Sn = 98.9%; Sp = 30.0; PPV = 96.2; NPV 60.0%; Kp = 0.378/p < 0.01. All methods performed better compared to SSS (29.4%) where the clinical diagnosis was doubtful (PCR = 94.15%; serum ELISA = 88.2%; combination = 94.1%; p < 0.01 for all). High serum anti-rKRP42 titers were seen in those with multiple lesions. Anti-rKRP42 urine ELISA was suboptimal as a diagnostic test. A 9% rate of positivity was seen for rk39-ICT, and positives recorded high anti-rKRP42 titers. The diagnostic accuracy can be increased above the level of the Gs by combining SSS and ELISA. Advanced studies are required to understand the association between rk39-ICT positivity and high anti-rKRP42 titers.

8.
Microorganisms ; 10(5)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35630433

RESUMO

The recent surge in cutaneous leishmaniasis (CL) in Sri Lanka has rendered clinical diagnosis difficult; thus, laboratory confirmation is indispensable. A modified (two novel inner primers to detect CL caused by Leishmania donovani) nested Internal Transcribed Spacer-1 (ITS1) PCR-Restriction Fragment Length Polymorphism (RFLP) method was developed and tested. The sensitivity of the modified nested PCR was tested using serial dilutions (103 to 10−2) of the DNA extract of a cultured L. donovani DD8 strain. Patients (n = 194) from Southern Sri Lanka were examined clinically, microscopically (Slit Skin Smear-SSS) and using the modified nested PCR. The modified nested PCR detected 2.55 fg of parasite DNA compared to ITS1 PCR (25 fg) and detected more cases than SSS (94.3% vs. 77.3%; p < 0.01). The RFLP pattern was L. donovani in all cases. The modified nested PCR performed well in clinically doubtful lesions (95% by PCR vs. 60% by SSS; p < 0.01), ulcerated nodules (91% vs. 71.8%; p < 0.01) and plaques (100% vs. 66.7%; p < 0.01). SSS demonstrated sensitivity (80.9%), specificity (81.8%), PPV (98.7%) and NPV (20.5%) against modified PCR. Low parasite loads and atypical lesions can be diagnosed by the proposed method with higher accuracy.

9.
Intern Med ; 61(18): 2813-2815, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35228420

RESUMO

Human diplogonoporiasis caused by the tapeworm Diplogonoporus balaenopterae has been rarely reported in Japan in the last decade. A 38-year-old man complained of a fever, diarrhea, intermittent abdominal pain, and worm excretion. He had a history of consuming raw juvenile Japanese anchovy one month earlier. On admission, the patient had acute enteritis and received intravenous fluids. During hospitalization, he excreted a white worm in his stool. On a macroscopic examination, the worm was found to be a tapeworm with scolexes. His health improved spontaneously without taking anthelmintic agents. Based on the genetic analysis, the tapeworm was identified as Diplogonoporus balaenopterae.


Assuntos
Anti-Helmínticos , Cestoides , Infecções por Cestoides , Adulto , Animais , Anti-Helmínticos/uso terapêutico , Cestoides/genética , Peixes , Humanos , Japão , Masculino
10.
Front Immunol ; 12: 612910, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248928

RESUMO

Hepatocyte infection by malaria sporozoites is a bottleneck in the life-cycle of Plasmodium spp. including P. falciparum, which causes the most lethal form of malaria. Therefore, developing an effective vaccine capable of inducing the strong humoral and cellular immune responses necessary to block the pre-erythrocytic stage has potential to overcome the spatiotemporal hindrances pertaining to parasite biology and hepatic microanatomy. We recently showed that when combined with a human adenovirus type 5 (AdHu5)-priming vaccine, adeno-associated virus serotype 1 (AAV1) is a potent booster malaria vaccine vector capable of inducing strong and long-lasting protective immune responses in a rodent malaria model. Here, we evaluated the protective efficacy of a hepatotropic virus, adeno-associated virus serotype 8 (AAV8), as a booster vector because it can deliver a transgene potently and rapidly to the liver, the organ malaria sporozoites initially infect and multiply in following sporozoite injection by the bite of an infected mosquito. We first generated an AAV8-vectored vaccine expressing P. falciparum circumsporozoite protein (PfCSP). Intravenous (i.v.) administration of AAV8-PfCSP to mice initially primed with AdHu5-PfCSP resulted in a hepatocyte transduction rate ~2.5 times above that seen with intramuscular (i.m.) administration. This immunization regimen provided a better protection rate (100% sterile protection) than that of the i.m. AdHu5-prime/i.m. AAV8-boost regimen (60%, p < 0.05), i.m. AdHu5-prime/i.v. AAV1-boost (78%), or i.m. AdHu5-prime/i.m. AAV1-boost (80%) against challenge with transgenic PfCSP-expressing P. berghei sporozoites. Compared with the i.m. AdHu5-prime/i.v. AAV1-boost regimen, three other regimens induced higher levels of PfCSP-specific humoral immune responses. Importantly, a single i.v. dose of AAV8-PfCSP recruited CD8+ T cells, especially resident memory CD8+ T cells, in the liver. These data suggest that boost with i.v. AAV8-PfCSP can improve humoral and cellular immune responses in BALB/c mice. Therefore, this regimen holds great promise as a next-generation platform for the development of an effective malaria vaccine.


Assuntos
Dependovirus/imunologia , Imunização Secundária/métodos , Fígado/imunologia , Vacinas Antimaláricas/imunologia , Malária Falciparum/prevenção & controle , Plasmodium falciparum/imunologia , Vacinas contra Adenovirus/imunologia , Animais , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Dependovirus/genética , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Memória Imunológica , Fígado/citologia , Fígado/efeitos dos fármacos , Vacinas Antimaláricas/administração & dosagem , Malária Falciparum/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Protozoários/imunologia , Vacinas de DNA/imunologia
11.
Pharmaceutics ; 13(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202866

RESUMO

The present study aims to evaluate the efficacy of a novel drug delivery system of the modified rice hydrogel containing praziquantel (PZQ) against Philophthalmus gralli isolated from ostrich eyes and determine the toxicity of the preparation on chicken eye model. The parasiticidal activity of PZQ (0, 1, 10, and 100 µg/mL) was tested on P. gralli. The ophthalmic antiparasitic hydrogel was formulated with appropriate amount of PZQ and chemically modified rice gel. The parasitic morphology after exposure with the preparation was examined under scanning electron microscope (SEM). The anthelminthic efficacy of the preparation on motility and mortality of parasites was performed by visual inspection and vital dye staining. The ocular irritation of the preparation was evaluated for 21 days using standard avian model followed by OECD 405. The results demonstrated that the parasiticidal activity of PZQ against P. gralli appears to be in a concentration- and time-dependent manner. In addition, the concentration of PZQ 10 µg/mL (Chi squared test, p = 0.003) and exposure time for 24 h (log-rank test, p = 0.0004) is sufficient to kill parasites, when statistically compared to negative control group. Rice hydrogel containing a lethal concentration of 10 µg/mL PZQ was successfully prepared. The preparation illustrated good parasitic killing and motile inhibiting effect on P. gralli compared with PZQ 10 µg/mL and its control (p < 0.05). An appearance under SEM of non-viable parasite after being incubated with the preparation, showing parasitic deformity, was observed comparing with the viable parasite in 0.9% normal saline solution (NSS). Moreover, no irritation of chicken eyes was also observed. Our results contribute to understanding the efficacy and the safety of the rice hydrogel of PZQ which have a predictive value for controlling P. gralli on the animal eyes. However, the pharmacological application needs to be further investigated for the best possible therapeutic approach.

12.
PLoS Negl Trop Dis ; 15(4): e0009352, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33857155

RESUMO

The natural infection of sand flies by Leishmania was investigated in Andean areas located between the Central and Eastern Cordilleras of northern Peru where cutaneous leishmaniasis caused by Leishmania (Viannia) peruviana is endemic. Sand flies were captured at five locations along the Utcubamba River in the Department of Amazonas, and morphologically identified under a microscope. Among 422 female sand flies dissected, the most dominant species was Pintomyia verrucarum (320 flies), followed by Pi. maranonensis (83 flies), Pi. robusta (13 flies), and Lutzomyia castanea (6 flies). Genetic analysis of sand flies from these areas together with those from other areas revealed that individuals of Pi. verrucarum were closely related regardless of morphological variation of their spermathecae. On the other hand, individuals of Pi. maranonensis collected in the study area were distant from those of other areas with genetic distances over the intraspecific level but mostly below the interspecific level, suggesting the unique characteristics of sand flies in this area. The natural infection of sand flies by flagellate parasites was detected mainly in the hindgut of each one of Pi. verrucarum and Pi. maranonensis. Both parasite species were identified as L. (V.) peruviana based on cytochrome b and mannose phosphate isomerase gene analyses. In addition, parasite species obtained from the lesion of a patient with cutaneous leishmaniasis in the study area in this period was identified as L. (V.) peruviana. These results strongly suggest that Pi. verrucarum and Pi. maranonensis are responsible for the transmission of L. (V.) peruviana in these areas. This is the first report of the natural infection of Pi. maranonensis by L. (V.) peruviana.


Assuntos
Leishmania/classificação , Leishmania/genética , Psychodidae/parasitologia , Animais , Feminino , Leishmania/isolamento & purificação , Peru , Filogenia
13.
Front Cell Infect Microbiol ; 11: 625001, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732663

RESUMO

Approximately 20 Leishmania species are known to cause cutaneous, mucocutaneous, and visceral disorders in humans. Identification of the causative species in infected individuals is important for appropriate treatment and a favorable prognosis because infecting species are known to be the major determinant of clinical manifestations and may affect treatments for leishmaniasis. Although Leishmania species have been conventionally identified by multilocus enzyme electrophoresis, genetic analysis targeting kinetoplast and nuclear DNA (kDNA and nDNA, respectively) is now widely used for this purpose. Recently, we conducted countrywide epidemiological studies of leishmaniasis in Ecuador and Peru to reveal prevalent species using PCR-RFLP targeting nDNA, and identified unknown hybrid parasites in these countries together with species reported previously. Furthermore, comparative analyses of kDNA and nDNA revealed the distribution of parasites with mismatches between these genes, representing the first report of mito-nuclear discordance in protozoa. The prevalence of an unexpectedly high rate (~10%) of genetically complex strains including hybrid strains, in conjunction with the observation of mito-nuclear discordance, suggests that genetic exchange may occur more frequently than previously thought in natural Leishmania populations. Hybrid Leishmania strains resulting from genetic exchanges are suggested to cause more severe clinical symptoms when compared with parental strains, and to have increased transmissibility by vectors of the parental parasite species. Therefore, it is important to clarify how such genetic exchange influences disease progression and transmissibility by sand flies in nature. In addition, our aim was to identify where and how the genetic exchange resulting in the formation of hybrid and mito-nuclear discordance occurs.


Assuntos
Leishmania , Leishmaniose Cutânea , Psychodidae , Animais , Humanos , Peru , Prevalência
14.
Acta Trop ; 215: 105807, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33385365

RESUMO

Cutaneous leishmaniasis (CL) is transmitted by Phlebotomine sand fly vectors, among which Phlebotomus papatasi is prevalent in Western Asia, Northern Africa and Southern Europe, and it is known as a vector for Leishmania major parasite in the world. However, in Iraq, morphological studies showed that P. papatasi is a predominant sand fly species and hypothesised to transmit CL causing Leishmania species including L. major and L. tropica. Few studies have found Leishmania species in sand flies in mixed pools of samples in this country. Accurate identification of sand flies as vectors of Leishmania species is required in Iraq. The current study aims to identify sand fly species, using both morphological and molecular phylogenetic analyses, in a region where CL tends to be endemic. Furthermore, molecular phylogenetic analysis has also used to confirm Leishmania species in the sand fly samples collected in 11 villages between Diyala and Sulaymaniyah Provinces. For the first time, we have found L. major in three individual sand flies, one engorged (with fresh blood meal) and two non-engorged (without visible fresh blood meal) P. papatasi females in an area of CL outbreaks since 2014-till now due to civil wars and internal conflicts happen in the region. Further study should be performed on sand fly population and Leishmania reservoirs in this region.


Assuntos
Surtos de Doenças , Insetos Vetores/parasitologia , Leishmania major/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Phlebotomus/parasitologia , Animais , Feminino , Iraque/epidemiologia , Leishmania major/genética , Leishmaniose Cutânea/parasitologia , Masculino , Filogenia
15.
Parasitol Int ; 80: 102179, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32853776

RESUMO

Plasmodium falciparum (P. falciparum) parasites still cause lethal infections worldwide, especially in Africa (https://www.who.int/publications/i/item/world-malaria-report-2019). During P. falciparum blood-stage infections in humans, low-density lipoprotein, high-density lipoprotein and cholesterol levels in the blood become low. Because P. falciparum lacks a de novo cholesterol synthesis pathway, it must import cholesterol from the surrounding environment. However, the origin of the cholesterol and how it is taken up by the parasite across the multiple membranes that surround it is not fully understood. To answer this, we used a cholesterol synthesis inhibiter (simvastatin), a cholesterol transport inhibitor (ezetimibe), and an activating ligand of the peroxisome proliferator-activated receptor α, called ciprofibrate, to investigate the effects of these agents on the intraerythrocytic growth of P. falciparum, both with and without HepG2 cells as the lipoprotein feeders. P. falciparum growth was inhibited in the presence of ezetimibe, but ezetimibe was not very effective at inhibiting P. falciparum growth when used in the co-culture system, unlike simvastatin, which strongly promoted parasite growth in this system. Ezetimibe is known to inhibit cholesterol absorption by blocking the activity of Niemann-Pick C1 like 1 (NPC1L1) protein, and simvastatin is known to enhance NPC1L1 expression in the human body's small intestine. Collectively, our results support the possibility that cholesterol import by P. falciparum involves hepatocytes, and cholesterol uptake into the parasite occurs via NPC1L1 protein or an NPC1L1 homolog during the erythrocytic stages of the P. falciparum lifecycle.


Assuntos
Colesterol/metabolismo , Eritrócitos/metabolismo , Ezetimiba/farmacologia , Ácidos Fíbricos/farmacologia , Hipolipemiantes/farmacologia , Plasmodium falciparum/fisiologia , Sinvastatina/farmacologia , Anticolesterolemiantes/farmacologia , Células Hep G2 , Humanos
16.
Biomed Rep ; 14(1): 6, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33235721

RESUMO

Histoplasmosis is a fungal infection caused by Histoplasma capsulatum (HC), which can occasionally be aggressive resulting in the formation of granulomatous lesions. These are usually located in the lungs; however, immunocompromised patients may occasionally develop disseminated lesions in other organs as well. Human immunodeficiency virus (HIV) primarily infects cells of the immune system expressing CD4 molecules. Not only does HIV multiply within these cells, but it can also kill them or otherwise cause loss of cellular function, leading to an immunocompromised state. As a result, in an immunocompromised patient, infection with HC can have serious implications, often the development of visceral histoplasmosis in different organs. Although several types of lesions are formed in HC-infected organs, it may be difficult to distinguish the causative organism from other pathogens based on morphology alone. The present case report describes the case of a 57-year-old woman, from South America, who may have been infected with HC >20 years previously, remaining asymptomatic over the years. She later developed a lesion in the duodenum associated with immunodeficiency caused by HIV infection. The differential diagnosis of this case was made on the basis of several specific morphological findings using histopathological analysis and molecular pathological techniques. The pathogenesis of characteristic lesions caused by HC in the presence of HIV infection was also reviewed.

17.
PLoS Negl Trop Dis ; 14(10): e0008797, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33075058

RESUMO

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mannose phosphate isomerase (mpi) gene was applied to 134 skin samples collected from patients with cutaneous leishmaniasis (CL) in Peru for identification of the infecting parasite at the species level, and the results were compared with those of cytochrome b (cyt b) gene sequencing obtained in previous studies. Although most results (121/134) including 4 hybrids of Leishmania (Viannia) braziliensis and L. (V.) peruviana corresponded to those obtained in the previous study, PCR-RFLP analyses revealed the distribution of putative hybrid strains between L. (V.) peruviana and L. (V.) lainsoni in two samples, which has never been reported. Moreover, parasite strains showing discordance between kinetoplast and nuclear genes (kDNA and nDNA), so-called mito-nuclear discordance, were identified in 11 samples. Of these, six strains had the kDNAs of L. (V.) braziliensis or L. (V.) peruviana and nDNAs of L. (V.) guyanensis, and three strains had the kDNAs of L. (V.) shawi and nDNAs of L. (V.) braziliensis. The rest were identified as mito-nuclear discordance strains having kDNAs of L. (V.) braziliensis or L. (V.) peruviana and nDNAs of L. (V.) lainsoni, and kDNAs of L. (V.) lainsoni and nDNAs of L. (V.) braziliensis. The results demonstrate that Leishmania strains in Peru are genetically more complex than previously considered.


Assuntos
Núcleo Celular/parasitologia , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Leishmania/genética , Leishmaniose Cutânea/parasitologia , Cruzamentos Genéticos , Citocromos b/genética , Humanos , Leishmania/classificação , Leishmania/isolamento & purificação , Peru , Filogenia , Proteínas de Protozoários/genética
18.
Am J Trop Med Hyg ; 103(2): 752-755, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32524951

RESUMO

An 88-year-old man with mutilating mucosal leishmaniasis (ML) involving septal perforation, with granulomas in the pharynx and larynx, was treated with oral miltefosine, 50 mg three times/day for 28 days. Miltefosine, an antineoplastic agent, is considered an alternative option for the treatment of ML, showing efficacies of 75-92% in Bolivia, Brazil, and Argentina. The patient denied having previous cutaneous (CL) leishmaniasis, and no CL lesions were recognized by physical examination. Parasites obtained from mucosal lesions were identified by cytochrome b gene sequencing as Leishmania guyanensis. Clinical cure was observed 2 months posttreatment, and no evidence of reactivation was observed in the 3-year follow-up. Adverse effects such as nausea, loss of appetite, and epigastric pain were experienced during treatment with miltefosine. There is a need for improved access to miltefosine in leishmaniasis-endemic areas of Latin America and a greater awareness of ML and its treatment among physicians working in endemic countries.


Assuntos
Antiprotozoários/uso terapêutico , Leishmaniose Mucocutânea/tratamento farmacológico , Doenças Nasais/tratamento farmacológico , Doenças Faríngeas/tratamento farmacológico , Fosforilcolina/análogos & derivados , Idoso de 80 Anos ou mais , Citocromos b/genética , Disfonia/etiologia , Humanos , Leishmania guyanensis/genética , Leishmania guyanensis/isolamento & purificação , Masculino , Perfuração do Septo Nasal/etiologia , Doenças Nasais/complicações , Doenças Nasais/patologia , Doenças Faríngeas/complicações , Doenças Faríngeas/patologia , Fosforilcolina/uso terapêutico , Índice de Gravidade de Doença
19.
Acta Trop ; 210: 105473, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32505596

RESUMO

Salivary gland transcriptome analysis of the Asiatic Triatoma rubrofasciata was performed by high-throughput RNA sequencing. This analysis showed that the majority of reads accounting for 85.38% FPKM (fragments per kilobase of exon per million mapped fragments) were mapped with a secreted class. Of these, the most abundant subclass accounting for 89.27% FPKM was the lipocalin family. In the lipocalin family, the most dominant molecules making up 70.49% FPKM were homologues of procalin, a major allergen identified from T. protracta saliva, suggesting an important role in blood-sucking of T. rubrofasciata. Other lipocalins showed similarities to pallidipin and triplatin, inhibitors of collagen-induced platelet aggregation identified from T. pallidipennis and T. infestans, respectively, Td38 from T. dimidiata with unknown function, triatin-like lipocalin with unknown function, and triafestin, an inhibitor of the activation of the kallikrein-kinin system, identified from T. infestans saliva. Other than lipocalin family proteins, homologues of antigen-5 (3.38% FPKM), Kazal-type serine protease inhibitor (1.36% FPKM), inositol polyphosphate 5-phosphatase (1.32% FPKM), and apyrase/5'-nucleotidase (0.64% FPKM) were identified as abundant molecules in T. rubrofasciata saliva. Through this study, de novo assembly of 42,580,822 trimmed reads generated 35,781 trinity transcripts, and a total of 1,272 coding sequences for the secreted class were deposited in GenBank. The results provide further insights into the evolution of salivary components in blood-sucking arthropods.


Assuntos
Glândulas Salivares/química , Triatoma/química , Animais , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Agregação Plaquetária , Glândulas Salivares/metabolismo , Triatoma/genética
20.
Data Brief ; 30: 105647, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32420432

RESUMO

The dataset in this report is related to the research article entitled: "Salivary gland transcriptome of the Asiatic Triatoma rubrofasciata" [1]. Lipocalin family proteins were identified as the dominant component in T. rubrofasciata saliva, and phylogenetic analysis of the salivary lipocalins resulted in the formation of five major clades (clade I-V). For further characterization, each clade of T. rubrofasciata lipocalin was subjected to alignment and phylogenetic analyses together with homologous triatomine lipocalins: procalin, a major allergen in T. protracta saliva and its homologue Td04 from T. dimidiata (clade I), pallidipin and triplatin, inhibitors of collagen-induced platelet aggregation identified from T. pallidipennis and T. infestans, respectively, and their homologue Pc20 identified from Panstrongylus chinai (clade II), Td30 and Td38 from T. dimidiata with unknown functions (clade III), triatin-like salivary lipocalins, Pc58 and Pc226 identified from P. chinai and Td18 from T. dimidiata (clade IV), and triafestin, an inhibitor of the activation of the kallikrein-kinin system, identified from T. infestans saliva and its homologues, Td25 and Td40 from T. dimidiata and Pc64 from P. chinai (clade V).

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