Antibacterial and immunological properties of piperine evidenced by preclinical studies: a systematic review

Aim: To review in vitro, in vivo, and in silico studies examining the antibacterial and immunomodulatory properties of piperine (PPN). Methods: This systematic review followed PRISMA guidelines, and five databases were searched. Results: A total of 40 articles were included in this study. Six aspects of PPN activity were identified, including antibacterial spectrum, association with antibiotics, efflux pump inhibition, biofilm effects, protein target binding, and modulation of immune functions/virulence factors. Most studies focused on Mycobacterium spp. and Staphylococcus aureus. Cell lineages and in vivo models were employed to study PPN antibacterial effects. Conclusion: We highlight PPN as a potential adjuvant in the treatment of bacterial infections. PPN possesses several antibacterial properties that need further exploration to determine the mechanisms behind its pharmacological activity.

Prevalence of ictal injuries in functional (psychogenic nonepileptic) seizures: A systematic review and meta-analysis

OBJECTIVE

Ictal injuries have long been considered typical signs of epileptic seizures. However, studies have shown that patients with functional seizures (FS)-also named psychogenic nonepileptic seizures-can also present these signs, misleading physicians and delaying a correct diagnosis. This systematic review aimed to assess the prevalence of injuries from FS.

METHODS

A literature search was performed in PubMed, Embase, LILACS (Latin American and Caribbean Health Sciences Literature), Scopus, Web of Science, PsycINFO, Google Scholar, OpenGrey, and ProQuest. Observational studies were included. The risk of bias was assessed using the Joanna Briggs Institute (JBI) checklist for studies reporting prevalence data. RStudio was used for meta-analyses. Cumulative evidence was evaluated according to Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

From the 2607 identified records, 41 studies were included in the qualitative synthesis, and 28 were included in meta-analyses. A meta-analysis of 13 studies, including 1673 individuals, resulted in an overall lifetime prevalence of injuries due to FS per person of 25% (95% confidence interval [CI] = 19%-32%, I2  = 88%). Considering a limited period (video-electroencephalographic [VEEG] monitoring days), a meta-analysis of 13 studies, including 848 individuals, resulted in an injury prevalence due to FS per person of .7% (95% CI = 0%-3%, I2  = 73%). Also, a meta-analysis of eight studies, including 1000 individuals, resulted in a prevalence of injuries per FS of .1% (95% CI = 0%-.98%, I2  = 49%). The certainty in cumulative evidence assessed by GRADE was rated "very low" for lifetime prevalence of injuries per person, "low" for prevalence per person during VEEG monitoring, and "moderate" for prevalence per number of FS.

SIGNIFICANCE

Overall pooled lifetime prevalence of injuries due to FS per person was 25%. In comparison, the prevalence of injuries per person during VEEG monitoring and per functional seizure was .7% and .1%, respectively. [Correction added on 07 October 2023, after first online publication: In the preceding sentence, 'consecutively' was corrected to 'respectively'.] The evidence of the occurrence of injuries due to FS breaks the paradigm that epileptic seizures can cause injuries but FS cannot.

In vitro effects of lapachol and β-lapachone against Leishmania amazonensis

Leishmaniasis is a neglected disease that affects millions of people worldwide, and special attention should be given to treatment because the available drugs have limitations, which can lead to low therapeutic adherence and parasitic resistance. This study evaluated the activity of the bioactive naphthoquinones, lapachol and β-lapachone, against Leishmania amazonensis. The cell alterations were evaluated in vitro on promastigote and amastigote forms. The lethal dose (LD50) at 24, 48, and 72 h on the promastigote's forms using lapachol was 75.60, 72.82, and 58.85 μg/mL and for β-lapachone was 0.65, 1.24, and 0.71 μg/mL, respectively. The naphthoquinones significantly inhibited the survival rate of L. amazonensis amastigotes at 83.11, 57.59, and 34.95% for lapachol (82.28, 41.14, and 20.57 µg/mL), and 78.49, 83.25, and 80.22% for β-lapachone (3.26, 1.63, and 0.815 µg/mL). The compounds on the promastigote's forms led to the loss of mitochondrial membrane potential, induced changes in the integrity of the membrane, caused damage to cells suggestive of the apoptotic process, and showed inhibition of tumor necrosis factor (TNF)-α and interleukin (IL)-6 production. The results showed that these naphthoquinones are promising candidates for research on new drugs with anti-Leishmania activity derived from natural products.

Inflammatory biomarkers on an LPS-induced RAW 264.7 cell model: a systematic review and meta-analysis

INTRODUCTION

Several experimental models have been designed to promote the development of new anti-inflammatory drugs. The in vitro model using RAW 264.7 cells has been widely used. However, there is still no consensus on which inflammatory mediators should initially be measured to screen for possible anti-inflammatory effects. To determine the rationality of measuring inflammatory mediators together with NO, such as the levels of tumor necrosis factor (TNF)-α, and interleukins (IL) 1β and 6, we carried out this systematic review (SR) and meta-analysis (MA).

METHODOLOGY

We conducted this SR and MA in accordance with the Preferred Reporting of Systematic Reviews and Meta-Analysis and the Cochrane Handbook for Systematic Reviews of Intervention. This review was registered in the Open Science Framework ( https://doi.org/10.17605/OSF.IO/8C3HT ).

RESULTS

LPS-induced cells produced high NO levels compared to non-LPS induced, and this production was not related to cell density. TNF-α, IL-1β, and IL-6, also showed high levels after cells had been stimulated with LPS. Though with some restrictions, all studies were reliable, as the risk of bias was detected in the test compounds and systems.

CONCLUSION

Measurement of NO levels may be sufficient to screen for possible anti-inflammatory action in the context of LPS-induced RAW 264.7 cells.

In vivo efficacy of meglumine antimoniate-loaded nanoparticles for cutaneous leishmaniasis: a systematic review

Background: Nanotechnology is a promising strategy to improve existing antileishmanial agents. Objective: To explore the evidence of encapsulated meglumine antimoniate for cutaneous leishmaniasis treatment in animal models. Materials & methods: The studies were recovered from PubMed, Scopus, EMBASE, LILACS, WoS and Google according to eligibility criteria following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Population, Intervention, Comparison, Outcomes and Study design (PICOS) strategy. Study appraisal was assessed using the Animal Research Reporting of In Vivo Experiments, SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) recommendations. Results: Five studies were included. Liposomes, metallic and polymeric nanoparticles were tested in BALB/c mice against Leishmania major, L. tropica or L. amazonensis. Limitations: Few studies were found to meet the eligibility criteria. Conclusion: All formulations had a significant efficacy, similar to the meglumine antimoniate reference treatment concerning the lesion size and parasite burden. The studies had a high and moderate risk of bias, and the confidence in cumulative evidence was considered low. Therefore, we encourage the development of high-quality preclinical studies. Registration: PROSPERO register CRD42020170191.

Genetic variations in the human immune system influence susceptibility to tegumentary leishmaniasis: a systematic review and meta-analysis

OBJECTIVES

The outcomes of tegumentary leishmaniasis (TL) rely on a complex interaction between the host immune system and the parasite. This study assessed the influence of polymorphisms in immune-related genes on TL.

METHODS

Web of Science, Scopus, PubMed, and Embase databases were searched systemically. The meta-analysis used a retrospective model in examining alleles, heterozygotes, and homozygotes. A quality assessment and an analysis of cumulative evidence were performed.

RESULTS

A total of 29 genes (encoding for cytokines, chemokines, and other immune receptors) and 84 polymorphisms were analyzed. The IL-1β_rs16944 (OR = 1.341, p = 0.003), TNF-α_rs1800629 (OR = 3.804, p = 0.004), MIF_rs755622 (OR = 3.357, p = 0.001), and INF- γ_rs243056 (OR = 1.670, p = 0.028) polymorphisms were speculated as risk factor for TL. They decrease the expression of the corresponding genes crucial for TL control. The quality assessment score was approximately 50%, suggesting the need for a clear method and polymorphism characterization for further comparison. The relevant risk of bias and other considerations resulted in low and moderate cumulative evidence confidence.

CONCLUSIONS

IL-1β_rs16944, TNF-α_rs1800629, MIF_rs755622, and INF-γ_rs2430561 polymorphisms were speculated as risk factor for TL, corroborating that IL-1β, TNF-α, INF-γ, and MIF are involved in the TL pathogenesis.

Campomanesia xanthocarpa (Mart.) O. Berg essential oil induces antileishmanial activity and remodeling of the cytoplasm organelles

Leishmaniasis is a neglected disease that affects millions of people worldwide. This study aimed to analyze antileishmanial activity of Campomanesia xanthocarpa leaf essential oil (EO) on promastigote and amastigote forms of Leishmania amazonensis, cytotoxicity in murine macrophages and sheep erythrocytes. The essential oil (EO) was analyzed by gas chromatography/mass spectrophotometry. The main and most abundant compounds were sesquiterpene hydrocarbons (71.22%) such as trans-caryophyllene (7.87%), bicyclogermacrene (11.28%), and δ-cadinene (8.34%). The IC₅₀ for promastigote and amastigote forms of L. amazonensis was 70 µg mL^-1 and 6 µg mL^-1, respectively. C. xanthocarpa EO was not cytotoxic for murine macrophages (CC₅₀ 1860 µg mL^-1) and sheep erythrocytes (1.5%), presenting high selectivity index for protozoan (310). C. xanthocarpa EO induced effects on the morphology and ultrastructure of this parasite. The high activity for intracellular amastigote forms, low toxicity to murine macrophages, and erythrocytes, suggest that C. xanthocarpa EO is promising for the treatment of leishmaniasis.

Photodynamic therapy in wound healing in vivo: a systematic review

Wounds constitute severe problems in public health. Inappropriate manipulation to promote wound healing and indiscriminate use of antibiotics may contribute to failure in wound treatment, leading to bacterial growth and resistance. Appropriate and correct approaches to wound treatment are crucially important. Further, the development of new and effective treatment modalities is important to decrease infection-related mortality and to reduce patient suffering and side effects. Photodynamic therapy (PDT) could be a promising approach to ameliorate this global health problem. We researched articles that used PDT in wound healing in vivo. The systematic review included articles that investigated the effect of PDT on wound healing in animals, published from May 2008 through 2018, in the databases PubMed and Web of Science. The main types of wounds described in the selected articles were burns, abrasions, and excisional wounds. Most of the studies tested PDT in wounds infected by methicillin-resistant Staphylococcus aureus, S. aureus standard strain, or Pseudomonas aeruginosa. The studies demonstrated that PDT contributes in several ways to the wound healing process, such as killing bacterial cells and stimulating the proliferation of fibroblasts and consequently of collagen and elastin. Based on these studies, PDT provided excellent results for the wound healing process, acting in several steps and accelerating tissue repair. PDT has proven to be a promising therapeutic modality, able to inhibit bacterial regrowth or kill bacteria, contributing significantly to accelerate the wound healing process.

Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) was characterized as an autoimmune condition with the production of antiphospholipid antibodies (aPL) associated with thrombosis and morbidity in pregnancy. The prevalence of aPL in the population ranges from 1% to 5% in patients with APS. The hypotheses regarding pathophysiological mechanisms are strongly related to binding proteins and antiphospholipid antibodies. The exact mechanisms by which they lead to clinical manifestations appear to be heterogeneous, but it is believed which aPL contribute to the cellular activation/coagulation, and so cause the thrombotic events. The treatment of APS should be an individual character and several factors should be taken into accounts, such as a number of antibodies, the age of the patient and the history of thrombotic events.

PCR primers designed for new world Leishmania: A systematic review

Studies of the primers that were designed to detect New World Leishmania were systematically reviewed to report the characteristics of each target, detection limit, specificity of the primers designed and diagnostic sensibility. The papers identified in the databases PubMed and Web of Science involved 50 studies. Minicircle is the most applied target in molecular research for diagnosis, due to its high sensitivity in detecting Leishmania in different clinical samples, a characteristic that can be partially attributed to the higher number of copies of the minicircle per cell. The other molecular targets shown in this review were less sensitive to diagnostic use because of the lower number of copies of the target gene per cell, but more specific for identification of the subgenus and/or species. The choice of the best target is an important step towards the result of the research. The target allows the design of primers that are specific to the genus, subgenus or a particular species and also imparts sensitivity to the method for diagnosis. The findings of this systematic review provide the advantages and disadvantages of the main molecular targets and primers designed for New World Leishmania, offering information so that the researcher can choose the PCR system best suited to their research need. This is a timely and extremely thorough review of the primers designed for New World Leishmania.

PERCEPÇÃO E CONSCIENTIZAÇÃO DE UNIVERSITÁRIOS SOBRE O SISTEMA ÚNICO DE SAÚDE

O objetivo desse estudo foi avaliar a percepção dos acadêmicos participantes do Programa de Educação Tutorial (PET) da Universidade Estadual de Maringá (UEM) sobre o Sistema Único de Saúde (SUS) e elucidá-los sobre os serviços disponibilizados pelo sistema, bem como seus direitos e deveres enquanto usuários. Um questionário semiestruturado foi aplicado e simultaneamente desenvolveu-se um processo de conscientização dos acadêmicos sobre a importância e funções do sistema para o Brasil por meio de dinâmicas e debates. Ao final do processo de conscientização, 97,97% dos petianos afirmaram ser usuário do SUS, comparado aos 72,97% que inicialmente declararam fazer uso do sistema. O conhecimento dos acadêmicos do PET-UEM sobre o SUS, embora satisfatório, é ainda limitado e carece de informações a respeito dos direitos e deveres enquanto usuários, sendo influenciado pela perspectiva midiática.

Contribution of photodynamic therapy in wound healing: A systematic review

OBJECTIVE

We researched articles that used photodynamic therapy (PDT) for skin wound healing in humans.

METHODS

The systematic review was conducted through scientific articles that investigated the action of PDT on wound healing in humans, published from July 2005 to March 2017, in the data bases PubMed and LILACS.

RESULTS

The main types of wound described in selected articles in this review were chronic ulcer and non-melanoma skin cancer. For accomplishing the PDT, second generation of photosensitizing agents with laser or light emitting diode were used. The studies demonstrated that PDT contribute in several ways to the wound healing process: leading to cellular death; reducing or increasing inflammation; stimulating fibroblasts proliferation and, consequently, of collagen and elastin; raising transforming growth factor beta and metalloproteinases. Based on this, PDT provided good results in wound healing process, acting in several steps and accelerating tissue repair.

CONCLUSIONS

PDT improved healing in many wound models in humans, revealing itself as a promising therapeutic modality for stimulating wound healing and remodelling.

Efficacy and Safety of the Immunization with DNA for Alzheimer's Disease in Animal Models: A Systematic Review from Literature

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disease that does not have a proven cure; however, one of the most promising strategies for its treatment has been DNA vaccines.

OBJECTIVE

The present review is aimed to report the new developments of the efficacy and safety of DNA vaccines for AD in animal models.

METHOD

The method PRISMA was used for this review. The article search was made in the electronic databases PubMed, LILACS, and Scopus using the descriptors ''Alzheimer disease" and ''Vaccine, DNA". Articles published between January 2001 and September 2017 in English, Portuguese, and Spanish were included.

RESULTS

Upon the consensus, the researchers identified 28 original articles. The studies showed satisfying results as for the decrease of amyloid plaques in mouse, rabbits, and monkeys brains using mostly the DNA Aβ42 vaccine, AV-1955, and AdPEDI-(Aβ1-6)11, mainly with a gene gun. In addition to a reduction in tau by the first DNA vaccine (AV-1980D) targeting this protein. The use of adjuvants and boosters also had positive results as they increased the destruction of the amyloid plaques and induced an anti-inflammatory response profile without side effects.

CONCLUSION

The results of DNA vaccines targeting the amyloid-β and the tau protein with or without adjuvants and boosters were promising in reducing amyloid plaques and tau protein without side effects in animals. Although there are many vaccines being tested in animals, few reach clinical trials. Thus, as a future perspective, we suggest that clinical studies should be conducted with vaccines that have been promising in animal models (e.g., DNA Aβ42 vaccine, AV-1955, and AdPEDI-(Aβ1-6)11).

Antiphospholipid syndrome and recurrent miscarriage: A systematic review and meta-analysis

Antiphospholipid syndrome (APS) is an autoimmune condition that is associated with thrombosis and morbidity in pregnancy. The exact mechanisms by which these associations occur appear to be heterogeneous and are not yet well understood. The aim of this study was to identify and analyze publications in recent years to better understand the diagnosis and its contribution to monitoring APS among women with recurrent miscarriage (RM). This systematic review and meta-analysis was conducted using the PubMed and Web of Knowledge databases, with articles published between 2010 and 2014, according to the PRISMA statement. Of the 85 identified studies, nine were selected. Most of the studies reported an association between recurrent miscarriage and specific antiphospholipid antibodies, as anticardiolipin antibodies (aCL), lupus anticoagulant (LA), anti-β2-glycoprotein I antibodies (aβ2GPI) and antiphosphatidylserine (aPS), which showed a relationship with RM. The main result of the meta-analysis revealed association between antiphospholipid antibodies (aPLs) and/or APS compared to the patients with RM (OR: 0.279; 95% CI: 0.212-0.366) and APS cases compared to the patients with RM (OR: 0.083; 95% CI: 0.036-0.189). High heterogeneity among these studies (I²=100.0%, p <0.001) was observed. In addition, there was no significant publication bias across studies according to Begg's test (p=0.230), although Egger's test (p=0.037) suggests significant publication bias. The funnel plot was slightly asymmetrical. Systematic review and meta-analysis demonstrated a positive association between antiphospholipid antibodies and/or antiphospholipid syndrome in patients with recurrent miscarriage.

EVOLUTION OF AMERICAN TEGUMENTARY LEISHMANIASIS CASES REPORTED IN PARANÁ STATE, BRAZIL

Leishmaniases are infectious diseases caused by protozoa of the genus Leishmania. They are widely distributed worldwide and endemic in 88 countries in four continents. The present study analyzed the reported cases of American Tegumentary Leishmaniasis (ATL) in Paraná State (Brazil) from January 2007 to December 2013. The data were grouped according to Regional Health (RH) districts and macroregions, which allowed visualization of the reality in each region in the state. A total of 2,879 ATL cases were reported and distributed among the 22 RH districts, with an average detection rate of 3.9 cases per 100,000 inhabitants. The northwestern region accounted for 50.1% of the total cases, and the northern region accounted for 26.0-76.1% of the reported cases. The 6^th RH district did not report any cases. The 7^th, 9^th, and 18^th RH districts had a higher cure rate (> 80%), and lower cure rates were found in the 1^st, 4^th, and 12^th RH districts. Reported unfavorable outcomes included treatment abandonment and death. Overall cure rates are based on the entire country, and unfavorable outcomes require greater attention of managers and health professionals to meet the goals of the Brazilian Ministry of Health.

Antileishmanial and immunomodulatory effects of the essential oil from Tetradenia riparia (Hochstetter) Codd

Cutaneous leishmaniasis usually presents therapeutic resistance to antimonials, and the existing therapies for leishmaniasis have many adverse effects and toxicity. Natural products may be regarded as possible candidates for alternative leishmaniasis treatment. The plant Tetradenia riparia has shown promise for the treatment of infectious diseases in folk medicine. We evaluated the antileishmanial activity of an essential oil from T. riparia (TrEO) and the modulatory effects of TrEO on cytokine modulation by peritoneal fluid cells that were infected with L. (L.) amazonensis. Peritoneal fluid cells were infected with Leishmania and incubated with TrEO (30 ng/mL) for 3, 6, and 24 h. Cytokines were screened using semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) and flow cytometry. Antileishmanial activity was evaluated at 24 h by microscopic counting and quantitative PCR (qPCR). TrEO treatment induced the death of 50% of Leishmania amastigotes (indicated by microscopic counting) and 91% of the parasite load (indicated by qPCR). TrEO inhibited some of the most critical cytokines for parasite growth and the establishment of infection, including granulocyte-macrophage colony-stimulating factor, interleukin-4 (IL-4), IL-10, and tumour necrosis factor. The parasite inhibited interferon-γ and IL-12, and TrEO blocked this inhibition, indicating that these cytokines are critical for activating mechanisms associated with the death and elimination of the parasite. These results suggest that TrEO may be an alternative leishmaniasis therapy when considering its antileishmanial and immunomodulatory activity.

Diagnostic methods to cutaneous leishmaniasis detection in domestic dogs and cats

Cutaneous leishmaniasis is caused by different species of Leishmania. In domestic animals such as dogs and cats, the diagnostic consists of clinical, epidemiological and serological tests, which changes among countries all around the world. Because of this diversity in the methods selected, we propose this systematic literature review to identify the methods of laboratory diagnosis used to detect cutaneous leishmaniasis in domestic dogs and cats in the Americas. Articles published in the last 5 years were searched in PubMed, ISI Web of Science, LILACS and Scielo, and we selected 10 papers about cutaneous leishmaniasis in dogs and cats in the Americas. In Brazil, often the indirect immunofluorescence and enzyme immunoassay (ELISA) have been applied. Other countries like United States and Mexico have been using antigenic fractions for antibodies detections by Western blot. ELISA and Western blot showed a higher sensitivity and efficacy in the detection of leishmaniasis. Analysis of sensibility and specificity of the methods was rarely used. Although confirmatory to leishmaniasis, direct methods for parasites detection and polymerase chain reaction showed low positivity in disease detection. We suggested that more than one method should be used for the detection of feline and canine leishmaniasis. Serological methods such as Western blot and enzyme immunoassay have a high efficacy in the diagnosis of this disease.

In vitro characterization of Leishmania (Viannia) braziliensis isolates from patients with different responses to Glucantime(®) treatment from Northwest Paraná, Brazil

Leishmaniasis is a group of diseases that presents various clinical manifestations. Many studies have shown that the parasite plays an important role in the clinical manifestations and prognosis of this disease. The cutaneous and mucosal forms of American tegumentary leishmaniasis (ATL) are associated with Leishmania (Viannia) braziliensis, which exhibits intraspecific genetic polymorphisms and various clinical manifestations. The present study focused on four different L. braziliensis strains that were isolated from patients with distinct Glucantime(®) treatment responses. The isolates were described based on their molecular, biological, and infective characteristics. Growth patterns in culture medium and different grow phases were analyzed, MID-Logarithimic (Mid-LOG), Logarithimic (LOG) and Stationary (STAT) phases. Complement resistance was evaluated using guinea pig serum. Infection to murine peritoneal macrophages, cytokine and nitric oxide were analyzed. Ultrastructural features were determined by transmission electron microscopy, and molecular characteristics were determined based on random amplified polymorphic DNA (RAPD). All of the L. braziliensis isolates showed typical growth and similar complement sensitivity patterns. Markedly lower infectivity indexes were observed for all strains in the LOG phase, with different cytokine profiles. The ultrastructure analysis revealed distinct differences between the MID-LOG, LOG, and STAT phases. The RAPD results showed a divergence between the isolates of the L. braziliensis. The in vitro characterization of L. braziliensis isolates from humans with different treatment responses using various parameters enabled us to observe differences among the isolates. Molecular and in vivo characterizations are currently under study to improve understanding of the parasite-host interaction that can imply in the clinical manifestation differences.

Evaluation of the reference value for the Montenegro skin test

INTRODUCTION

The Montenegro skin test (MST) has good clinical applicability and low cost for the diagnosis of American tegumentary leishmaniasis (ATL). However, no studies have validated the reference value (5mm) typically used to discriminate positive and negative results. We investigated MST results and evaluated its performance using different cut-off points.

METHODS

The results of laboratory tests for 4,256 patients with suspected ATL were analyzed, and 1,182 individuals were found to fulfill the established criteria. Two groups were formed. The positive cutaneous leishmaniasis (PCL) group included patients with skin lesions and positive direct search for parasites (DS) results. The negative cutaneous leishmaniasis (NCL) group included patients with skin lesions with evolution up to 2 months, negative DS results, and negative indirect immunofluorescence assay results who were residents of urban areas that were reported to be probable sites of infection at domiciles and peridomiciles.

RESULTS

The PCL and NCL groups included 769 and 413 individuals, respectively. The mean ± standard deviation MST in the PCL group was 12.62 ± 5.91mm [95% confidence interval (CI): 12.20-13.04], and that in the NCL group was 1.43 ± 2.17mm (95% CI: 1.23-1.63). Receiver-operating characteristic curve analysis indicated 97.4% sensitivity and 93.9% specificity for a cut-off of 5mm and 95.8% sensitivity and 97.1% specificity for a cut-off of 6mm.

CONCLUSIONS

Either 5mm or 6mm could be used as the cut-off value for diagnosing ATL, as both values had high sensitivity and specificity.

Antileishmanial activity of the essential oil from Tetradenia riparia obtained in different seasons

The herbaceous shrub Tetradenia riparia has been traditionally used to treat inflammatory and infectious diseases. Recently, a study showed that T. riparia essential oil (TrEO) obtained in summer has antileishmanial effects, although these results could be influenced by seasonal variation. This study evaluated the activity of the TrEO obtained in different seasons against Leishmania (Leishmania) amazonensis, in vitro and in vivo. The compounds in the TrEO were analysed by gas chromatography-mass spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO reduced intracellular amastigote infection, independently of season. The TrEO from plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO production did not change in samples of the TrEO from different seasons. The antileishmanial effect in vivo consisted of a reduction of the parasite load in the spleen. These results suggest that the TrEO has potential effects on L. (L.) amazonensis, consonant with its traditional use to treat parasitic diseases.

Antileishmanial activity of essential oil and 6,7-dehydroroyleanone isolated from Tetradenia riparia

Tetradenia riparia plant is used as a traditional medicine in Africa for the treatment of inflammatory and infectious diseases as like parasitic. Therapy for leishmaniasis caused by Leishmania (Leishmania) amazonensis specie often fails, and the conventional drugs are toxic, expensive, require a long period of treatment, and adverse effects are common. The alternative therapies using natural products are inexpensive and have few or any adverse reaction. These reasons are sufficient to investigate the new natural therapeutic for leishmaniasis. We evaluated the potential of the essential oil (TrEO) and 6,7-dehydroroyleanone (TrROY) isolated from T. riparia on L. (L.) amazonensis promastigote and amastigote forms, cytotoxicity on human erythrocytes and murine macrophages, nitric production and inducible nitric oxide synthase (iNOS) mRNA expression. TrEO was the most effective to promote the Leishmania promastigote death. After 72 h incubation, the lethal dose of TrEO and TrROY that promoted 50% Leishmania death (LD50) were 0.8 μg/mL and 3 μg/mL, respectively. TrEO and TrROY were not cytotoxic to human erythrocytes, but TrROY was toxic to murine macrophages resulting in a low selectivity index. The transmission electronic microscopy showed that TrEO (0.03 μg/mL) was able to modify the promastigote ultrastructures suggesting autophagy as chromatin condensation, blebbing, membranous profiles and nuclear fragmentation. Infected-macrophages treated with TrEO (0.03 μg/mL) or TrROY (10 μg/mL) had an infection index decreased in 65 and 48%. TrEO did not induce iNOS mRNA expression or nitrite production in macrophages infected with Leishmania. TrROY and mainly TrEO promoted the Leishmania death, and TrROY showed loss toxicity to erythrocytes cells. Other compounds derived from T. riparia and the essential oil could be explored to develop a new alternative treatment for leishmaniasis.

Activity of antiretroviral drugs in human infections by opportunistic agents

Highly active antiretroviral therapy (HAART) is used in patients infected with HIV. This treatment has been shown to significantly decrease opportunist infections such as those caused by viruses, fungi and particularly, protozoa. The use of HAART in HIV-positive persons is associated with immune reconstitution as well as decreased prevalence of oral candidiasis and candidal carriage. Antiretroviral therapy benefits patients who are co-infected by the human immunodeficiency virus (HIV), human herpes virus 8 (HHV-8), Epstein-Barr virus, hepatitis B virus (HBV), parvovirus B19 and cytomegalovirus (CMV). HAART has also led to a significant reduction in the incidence, and the modification of characteristics, of bacteremia by etiological agents such as Staphylococcus aureus, coagulase negative staphylococcus, non-typhoid species of Salmonella, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Mycobacterium tuberculosis. HAART can modify the natural history of cryptosporidiosis and microsporidiosis, and restore mucosal immunity, leading to the eradication of Cryptosporidium parvum. A similar restoration of immune response occurs in infections by Toxoplasma gondii. The decline in the incidence of visceral leishmaniasis/HIV co-infection can be observed after the introduction of protease inhibitor therapy. Current findings are highly relevant for clinical medicine and may serve to reduce the number of prescribed drugs thereby improving the quality of life of patients with opportunistic diseases.

Acaricidal activity of the essential oil from Tetradenia riparia (Lamiaceae) on the cattle tick Rhipicephalus (Boophilus) microplus (Acari; Ixodidae)

Tetradenia riparia (Lamiaceae) is a well-known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of T. riparia essential oil (EO) against engorged females of Rhipicephalus (Boophilus) microplus (Acari; Ixodidae). For this purpose, nine serial concentrations (12.50%, 6.25%, 3.75%, 1.80%, 0.90%, 0.45%, 0.22%, 0.11%, and 0.056% w/v) of T. riparia were used for the adult immersion test (AIT). For the larval packet test (LPT), we used 14 serial concentrations (100.00%, 50.00%, 25.00%, 12.50%, 6.25%, 3.65%, 1.82%, 0.91%, 0.45%, 0.228%, 0.114%, 0.057%, 0.028%, and 0.014% w/v). The results for AIT showed 100.00% and 2.05% mortality, 19.00 and 90.20% for the total number of eggs, egg-laying inhibition of 0.00% and 90.20%, hatchability inhibition of 0.00% and 70.23%, and product effectiveness of 100.00% and 2.89%, respectively. The AIT indicated that the LC(50) and LC(99.9), calculated using the Probit test, were for mortality (%) 0.534g/mL (0.436-0.632) and 1.552g/mL (1.183-1.92); for total number of eggs were 0.449g/mL (0.339-0.558) and 1.76g/mL (1.27-2.248); and for hatchability inhibition were 0.114g/mL (0.0-0.31) and 2.462g/mL (1.501-3.422), respectively. Larvae between 14 and 21days old were fasted and placed in each envelope. Bioassays were performed at 27°±1°C, RH⩾80%. Larval mortality was observed 24h after treatment and showed 10.60-100% mortality in the LPT bioassay. The LPT showed that the LC(50) and LC(99.9) were 1.222g/mL (0.655-1.788) and 11.382g/mL (7.84-14.91), respectively. A positive correlation between T. riparia EO concentration and tick control, was observed by the strong acaricidal effects against R. (B.) microplus, and the mortality rate of ticks was dose-dependent. Our results showed that T. riparia is a promising candidate as an acaricide against resistant strains of R. (B.) microplus.