Wunderlich syndrome as a rare complication of polyarteritis nodosa: a case report.

Spontaneous subcapsular and perirenal hemorrhage, known as Wunderlich syndrome (WS), is a rare clinical manifestation of polyarteritis nodosa (PAN). We report a case of a 48-year-old male with a history of recurrent episodes of leg muscle tenderness and dysesthesia, bilateral flank pain, painful nodular skin lesions in the lower limbs, weight loss, and difficult-to-control arterial hypertension. The abdominopelvic computed tomography angiography showed a large left perirenal hematoma, leading to the patient's admission to the intensive care unit. After the exclusion of infectious or neoplastic foci, the patient was diagnosed with PAN and started intravenous methylprednisolone pulses with a good response. Since WS is a rare initial clinical manifestation of PAN, an early diagnosis and aggressive treatment will significantly improve clinical outcomes.

All-optical half-adder in a linear three-core fiber device.

The half-adder is one of the most useful combinational logic functions for data processing. Many research papers in the literature propose nonlinear all-optical half-adders. Few studies propose linear all-optical devices, and those that do usually employ microstructured 2D photonic crystals. This work presents the numerical acquisition of an all-optical half-adder using a linear three-core fiber device. The device presents high performance and acceptable values of fabrication and modulation tolerance. It can be made using any fiber technology and propagated by pulses of any wavelength. Depending on the type of fiber used, the precision needed to fabricate the device's smallest structures can range from 20 nm to 90 nm. This result is evidence of the possibility of obtaining nonlinear logical processing using only fiber design.

Modulation of the functional interfaces between retroviral intasomes and the human nucleosome.

Infection by retroviruses as HIV-1 requires the stable integration of their genome into the host cells. This process needs the formation of integrase (IN)-viral DNA complexes, called intasomes, and their interaction with the target DNA wrapped around nucleosomes within cell chromatin. To provide new tools to analyze this association and select drugs, we applied the AlphaLISA technology to the complex formed between the prototype foamy virus (PFV) intasome and nucleosome reconstituted on 601 Widom sequence. This system allowed us to monitor the association between both partners and select small molecules that could modulate the intasome/nucleosome association. Using this approach, drugs acting either on the DNA topology within the nucleosome or on the IN/histone tail interactions have been selected. Within these compounds, doxorubicin and histone binders calixarenes were characterized using biochemical, in silico molecular simulations and cellular approaches. These drugs were shown to inhibit both PFV and HIV-1 integration in vitro. Treatment of HIV-1-infected PBMCs with the selected molecules induces a decrease in viral infectivity and blocks the integration process. Thus, in addition to providing new information about intasome-nucleosome interaction determinants, our work also paves the way for further unedited antiviral strategies that target the final step of intasome/chromatin anchoring. IMPORTANCE In this work, we report the first monitoring of retroviral intasome/nucleosome interaction by AlphaLISA. This is the first description of the AlphaLISA application for large nucleoprotein complexes (>200 kDa) proving that this technology is suitable for molecular characterization and bimolecular inhibitor screening assays using such large complexes. Using this system, we have identified new drugs disrupting or preventing the intasome/nucleosome complex and inhibiting HIV-1 integration both in vitro and in infected cells. This first monitoring of the retroviral/intasome complex should allow the development of multiple applications including the analyses of the influence of cellular partners, the study of additional retroviral intasomes, and the determination of specific interfaces. Our work also provides the technical bases for the screening of larger libraries of drugs targeting specifically these functional nucleoprotein complexes, or additional nucleosome-partner complexes, as well as for their characterization.

Two step calibration method for ozone low-cost sensor: Field experiences with the UrbanSense DCUs.

Urban air pollution is a global concern impairing citizens' health, thus monitoring is a pressing need for city managers. City-wide networks for air pollution monitoring based on low-cost sensors are promising to provide real-time data with detail and scale never before possible. However, they still present limitations preventing their ubiquitous use. Thus, this study aimed to perform a post-deployment validation and calibration based on two step methods for ozone low-cost sensor of a city-wide network for air pollution and meteorology monitoring using low-cost sensors focusing on the main challenges. Four of the 23 data collection units (DCUs) of the UrbanSense network installed in Porto city (Portugal) with low-cost sensors for particulate matter (PM), carbon monoxide (CO), ozone (O3), and meteorological variables (temperature, relative humidity, luminosity, precipitation, and wind speed and direction) were evaluated. This study identified post-deployment challenges related to their validation and calibration. The preliminary validation showed that PM, CO and precipitation sensors recorded only unreliable data, and other sensors (wind speed and direction) very few data. A multi-step calibration strategy was implemented: inter-DCU calibration (1st step, for O3, temperature and relative humidity) and calibration with a reference-grade instrument (2nd step, for O3). In the 1st step, multivariate linear regression (MLR) resulted in models with better performance than non-linear models such as artificial neural networks (errors almost zero and R2 > 0.80). In the 2nd step, the calibration models using non-linear machine learning boosting algorithms, namely Stochastic Gradient Boosting Regressor (both with the default and post-tuning hyper-parameters), performed better than artificial neural networks and linear regression approaches. The calibrated O3 data resulted in a marginal improvement from the raw data, with error values close to zero, with low predictability (R2 ∼ 0.32). The lessons learned with the present study evidenced the need to redesign the calibration strategy. Thus, a novel multi-step calibration strategy is proposed, based on two steps (pre and post-deployment calibration). When performed cyclically and continuously, this strategy reduces the need for reference instruments, while probably minimising data drifts over time. More experimental campaigns are needed to collect more data and further improve calibration models.

All-optical digital multiplexer/demultiplexer in a linear three-core fiber device.

Digital multiplexers/demultiplexers (MUX/DEMUXes) are essential for computing, data transmission, and data processing. However, research on all-optical digital MUX/DEMUXes is scarce and generally proposes single-function nonlinear devices. This work presents the numerical acquisition of all-optical digital MUX/DEMUXes using a linear three-core fiber device. Our device, called the interchanging-cores planar three-core fiber coupler, is propagated by low-powered amplitude modulated pulses, can operate with pulses of any wavelength, and can be made using any fiber technology. This result is further evidence of the possibility of obtaining logical processing, even nonlinear logical processing, using fiber-only design.

Reproductive alterations of Biomphalaria glabrata (Say, 1818) infected with Angiostrongylus cantonensis (Chen, 1935) and exposed to Euphorbia milii var. hislopii latex.

The natural phytochemical latex of Euphorbia milii var. hislopii is one of the most promising natural molluscicides for the control of Biomphalaria glabrata, and has been widely studied under laboratory conditions for selective control of schistosomiasis transmission. However, the effect of this product on B. glabrata infected by other helminths had not yet been investigated. The present study reports evaluation of the effect of E. milii var. hislopii latex on the survival and reproductive activity of B. glabrata infected by Angiostrongylus cantonensis. For this purpose, the following groups were formed: control (C), exposed (E), infected (I) and infected and exposed for different time intervals (1 day - I+E-1D, 7 days - I+E-7D, 14 days - I+E-14D, 21 days - I+E-21D and 28 days - I+E-28D). The experimental infection was performed with L1 larvae of A. cantonensis and exposure to 0.08 mg/L (LC50) of E. milii latex for a period of 24 hours. We analyzed the effects of E. milii latex on the survival of snails during four weeks, reproductive parameters and possible histophysiopathological changes in the gonad and albumen gland of the snails. Regarding survival, there was reduction of more than 50% in the groups exposed to latex (E and I + E) compared to the control group. As for the number of ovigerous masses, eggs, and average number of hatched snails, significant increases were observed in the I+E-1D group at the 4th week compared to the control group and the other weeks in the same group. Angiostrongylus cantonensis larvae were observed in the gonad and albumen gland from day 21 and 28 of infection in groups I and I+E, respectively, with granuloma-like formation. At these observation periods and in these groups, an increase in galactogen was observed in the albumen gland, which influenced egg laying, suggesting the existence of a fecundity compensation mechanism phenomenon. It was possible to conclude that both stressors - A. cantonensis infection and exposure to E. milii latex - directly influenced the survival and reproductive parameters of B. glabrata.

mm-wave Rydberg-Rydberg transitions gauge intermolecular coupling in a molecular ultracold plasma.

Out-of-equilibrium, strong correlation in a many-body system can trigger emergent properties that act to constrain the natural dissipation of energy and matter. Signs of such self-organization appear in the avalanche, bifurcation, and quench of a state-selected Rydberg gas of nitric oxide to form an ultracold, strongly correlated ultracold plasma. Work reported here focuses on the initial stages of avalanche and quench and uses the mm-wave spectroscopy of an embedded quantum probe to characterize the intermolecular interaction dynamics associated with the evolution to plasma. Double-resonance excitation prepares a Rydberg gas of nitric oxide composed of a single selected state of principal quantum number, n0. Penning ionization, followed by an avalanche of electron-Rydberg collisions, forms a plasma of NO+ ions and weakly bound electrons, in which a residual population of n0 Rydberg molecules evolves to a state of high orbital angular momentum, ℓ. Predissociation depletes the plasma of low-ℓ molecules. Relaxation ceases and n0ℓ(2) molecules with ℓ ≥ 4 persist for very long times. At short times, varying excitation spectra of mm-wave Rydberg-Rydberg transitions mark the rate of electron-collisional ℓ-mixing. Deep depletion resonances that persist for long times signal energy redistribution in the basis of central-field Rydberg states. The widths and asymmetries of Fano line shapes witness the degree to which coupling in the arrested bath (i) broadens the allowed transition and (ii) mixes the local network of levels in the ensemble.

Developing and validating high-value patient digital follow-up services: a pilot study in cardiac surgery.

BACKGROUND: The existing digital healthcare solutions demand a service development approach that assesses needs, experience, and outcomes, to develop high-value digital healthcare services. The objective of this study was to develop a digital transformation of the patients' follow-up service after cardiac surgery, based on a remote patient monitoring service that would respond to the real context challenges. METHODS: The study followed the Design Science Research methodology framework and incorporated concepts from the Lean startup method to start designing a minimal viable product (MVP) from the available resources. The service was implemented in a pilot study with 29 patients in 4 iterative develop-test-learn cycles, with the engagement of developers, researchers, clinical teams, and patients. RESULTS: Patients reported outcomes daily for 30 days after surgery through Internet-of-Things (IoT) devices and a mobile app. The service's evaluation considered experience, feasibility, and effectiveness. It generated high satisfaction and high adherence among users, fewer readmissions, with an average of 7 ± 4.5 clinical actions per patient, primarily due to abnormal systolic blood pressure or wound-related issues. CONCLUSIONS: We propose a 6-step methodology to design and validate a high-value digital health care service based on collaborative learning, real-time development, iterative testing, and value assessment.

Insights on catheter-related bloodstream infections: a prospective observational study on the catheter colonization and multidrug resistance.

BACKGROUND: Central venous catheter-related bloodstream infection (CRBSI) is a huge public health concern with considerable impact on mortality and health costs. AIM: A three-year observational study enrolling three tertiary hospitals located in Lisbon, Portugal, was designed to identify the major aetiological agents of CRBSI, their ability to colonize central venous catheters and their antimicrobial resistance profiles. METHODS: Aetiological agents of CRBSI were identified by Vitek 2. Whole-genome sequencing was used to confirm CRBSI by the most prevalent aetiological agents and characterize their resistome. Central venous catheter colonization (namely by biofilm assembly) was monitored by scanning electron microscopy. FINDINGS: Staphylococci were the most prevalent causative agent (36/58, 62.0%), with S. aureus and coagulase-negative S. epidermidis accounting for 24.1% and 36.2% of CRBSIs, respectively. Fifty-nine of 72 staphylococci isolates were meticillin resistant. Comparative genomic analysis of central venous catheters/haemoculture pairs of isolates revealed genomic matches for 35 of 36 pairs and a good correlation between antibiotic susceptibility phenotype and the presence of antimicrobial resistance genetic determinants. Biofilms were present on 48.6% of the central venous catheters; nevertheless, no statistically significant association was established between biofilm assembly and CRBSI, and the presence/absence of ica operon and agr groups did not correlate with biofilm phenotypes, highlighting the need for further studies to elucidate biofilms' role on this healthcare-associated infection. CONCLUSION: Whole-genome sequencing was shown to be a valuable tool to confirm CRBSI. Although more than 42.3% of the central venous catheters were colonized by staphylococci, no statistically significant association was found between CRBSI and biofilms.

Pythium and Phytopythium species associated with weeds collected in vegetable production fields in Brazil.

This study aimed to identify Pythium and Phytopythium species from weeds collected in vegetable fields and test their pathogenicity. Weeds with symptoms of damping-off, root rot or wilt were sampled in the Brazilian states of Ceará, Goiás and Pernambuco, as well as in the Distrito Federal, for isolation and identification of the causal agents. Once isolated, colonies with typical Pythium and Phytopythium characteristics grew in selective V8 medium. Procedures for species identification included morphology and amplification of the ITS and Cox II regions, which were compared with other accessions available at GenBank. The phylogenetic relationships among the isolates and pathogenicity to their original hosts were evaluated. Six Pythium species were identified: P. aphanidermatum, P. oopapillum, P. orthogonon, P. ultimum var. ultimum, P. myriotylum and P. sylvaticum, and two species of Phytopythium, Phy. chamaehyphon and Phy. oedochilum. In the pathogenicity tests, the 10 weed hosts showed symptoms of damping-off or root rot after inoculation, with exception of Portulaca oleraceae in which none of the isolates was pathogenic. Therefore, common weeds in vegetable fields areas can host different Pythium and Phytopythium species and play an important role in the epidemiology of vegetable diseases, in particular on pathogen survival and population increase.

Characterization of biofilm structure and properties via processing of 2D optical coherence tomography images in BISCAP.

MOTIVATION: Processing of Optical Coherence Tomography (OCT) biofilm images is currently restricted to a set of custom-made MATLAB scripts. None of the tools currently available for biofilm image processing (including those developed for Confocal Laser Scanning Microscopy-CLSM) enable a fully automatic processing of 2D OCT images. RESULTS: A novel software tool entitled Biofilm Imaging and Structure Classification Automatic Processor (BISCAP) is presented. It was developed specifically for the automatic processing of 2D OCT biofilm images. The proposed approach makes use of some of the key principles used in CLSM image processing, and introduces a novel thresholding algorithm and substratum detection strategy. Two complementary pixel continuity checks are executed, enabling very detailed pixel characterizations. BISCAP delivers common structural biofilm parameters and a set of processed images for biofilm analysis. A novel biofilm 'compaction parameter' is suggested. The proposed strategy was tested on a set of 300 images with highly satisfactory results obtained. BISCAP is a Python-based standalone application, not requiring any programming knowledge or property licenses, and where all operations are managed via an intuitive Graphical User Interface. The automatic nature of this image processing strategy decreases biasing problems associated to human-perception and allows a reliable comparison of outputs. AVAILABILITY AND IMPLEMENTATION: BISCAP and a collection of biofilm images obtained from OCT scans can be found at: https://github.com/diogonarciso/BISCAP. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Evaluation of the reproductive profile of Subulina octona (Gastropoda, Subulinidae) experimentally infected by Paratanaisia bragai (Digenea, Eucotylidae) / Avaliação do perfil reprodutivo de Subulina octona (Gastropoda, Subulinidae) infectada experimentalmente por Paratanaisia bragai (Digenea, Eucotylidae)

Abstract Snails infected by trematodes may increase or decrease their reproductive activity in response to the presence of infection. Our aim was to verify the reproductive alterations in Subulina octona after infection by Paratanaisia bragai. The infected snails were individually exposed for 24 hours to 20 parasite eggs and four groups were formed (10, 20, 30 and 40 d.p.i.- days after infection), along with control groups. Every 10 days, the number of eggs in the reproductive tract, number of eggs hatched, galactogen content and histopathological changes were evaluated. The reproductive in the control and infected snails presented an alternating pattern, where periods of high production of eggs and newly hatched were followed by periods of low production. However, in relation to the amount of galactogen, both control and infected groups followed the same pattern of variation. In the histology, we observed the presence of male and female gametes with marked reduction in the number of oocytes. The results indicate that the intra-snail development of the parasite affects the reproductive biology of the host.

Resumo Moluscos infectados por trematódeos podem aumentar ou diminuir sua atividade reprodutiva em resposta à presença da infecção. Nosso objetivo foi verificar as alterações reprodutivas de Subulina octona após a infecção por Paratanaisia bragai. Os moluscos infectados foram individualmente expostos durante 24 horas a 20 ovos do parasito e quatro grupos foram formados (10, 20, 30 e 40 d.p.i. - dias pós infecção), com respectivos grupos controle. A cada 10 dias, o número de ovos no trato reprodutivo, o número de ovos eclodidos, o conteúdo de galactogênio e alterações histopatológicas eram avaliadas. O padrão reprodutivo nos moluscos controle e infectados evidenciou um comportamento alternante, nos quais períodos de alta produção de ovos e filhotes foram seguidos por períodos de baixa produção. No entanto, em relação ao conteúdo de galactogênio, moluscos controle e infectados seguiram o mesmo padrão de variação. Na histologia, observamos a presença de gametas masculinos e femininos com acentuada redução no número de óocitos. Os resultados indicam que o desenvolvimento intramolusco do parasito afeta a biologia reprodutiva do hospedeiro.

Linear multi-functional logic gate in a three-core photonic crystal fiber.

The growth of transmission rates in optical fibers can increase the demand for devices that perform network node processing. Usually, such devices achieve complex optical signal processing through high non-linearity effects and optoelectronic devices. In this work, we present the numerical acquisition of a configurable multi-function logic gate in which the OR and AND gates can be enabled based on the logic values entered in a selector. Our device consists of a single piece of three-core PCF, with linear pulse propagation, and without the need for any other mechanisms. This result presents evidence that information processing within functional fibers is possible and might be achieved using only fiber design.

Endometrial carcinoma metastatic to the scalp: a rare case report and literature review / O Carcinoma endometrial é uma causa rara de metástases cutâneas

ABSTRACT: Endometrial carcinoma is a very rare cause of cutaneous metastasis.The most frequent presentations of cutaneous metastasis are fast developing nodules or tumors, which are evi-dence of widespread dissemination in such patients.We report a case of scalp metastasis from an endometrial adenocarcinoma with a fatal prognosis. (AU)

RESUMO: O carcinoma endometrial é uma causa rara de metástases cutâneas.A apresentação mais frequente de metástases cutâneas são nódulos ou tumores de rápido desenvolvimento, que evidenciam uma disseminação generalizada nesses pacientes.Relatamos um caso de metástase no couro cabeludo de um adenocarcinoma endometrial com prognóstico fatal. (AU)

Can biochemical endpoints improve the sensitivity of the biomonitoring strategy using bioassays with standard species, for water quality evaluation?

The Water Framework Directive (WFD) was adopted in 2000 and is a common framework for water policy, management and protection in Europe. The WFD assesses specific parameters; however, it ignores indicators of ecosystem functioning and sub-individual performance. Reservoirs are strongly influenced by anthropogenic activities that promote their imbalance. Bioassays and biomarkers are useful tools to link the chemical, ecological and toxicological assessments in water quality assessments. These approaches can be complementary to WFD methodologies, allowing the detection of impacts on the ecosystem. This study evaluated if the biochemical parameters can improve the sensitivity of the biomonitoring strategy using bioassays with the standard species Daphnia magna, in the assessment of the ecological quality of water reservoirs. To this end, water samples of Portuguese reservoirs were analysed in three sampling periods (Autumn 2018 and Spring, Autumn 2019). In parallel, a physicochemical characterization of waters was performed. D. magna feeding rate assays were performed for 24 h. After exposure, metabolism, oxidative stress and lipid peroxidation biomarkers were evaluated. Feeding rate assays showed sensitivity to different reservoirs. Biomarkers showed a higher sensitivity and can therefore improve the sensitivity of the biomonitoring strategy using bioassays. Bioassays and biomarkers approach allowed to highlight potential sources of stress, more related to the quality of the seston than to chemical contamination. This work highlights the complementarity between bioassays and biomarkers to identify ecotoxicological effects of surface waters, and can be extremely useful, especially in cases where the biotic indices are difficult to establish, such as reservoirs.

Preventive oral supplementation with Bifidobacterium longum 51A alleviates oxazolone-induced allergic contact dermatitis-like skin inflammation in mice.

Allergic contact dermatitis (ACD) is a common allergic skin disease that affects individuals subjected to different antigen exposure conditions and significantly impacts the quality of life of those affected. Numerous studies have demonstrated that probiotics suppress inflammation through immunomodulatory effects. In this study, we aimed to evaluate the effect of the probiotic Bifidobacterium longum 51A as a preventive treatment for ACD using an oxazolone-induced murine model. We demonstrated that B. longum 51A exerted a prophylactic effect on oxazolone-induced ACD-like skin inflammation via reductions in ear and dermal thickness and leucocyte infiltration. The administration of inactivated B. longum 51A did not affect oxazolone-induced ACD-like skin inflammation, suggesting that the bacteria must be alive to be effective. Given that B. longum 51A is an acetate producer, we treated mice with acetate intraperitoneally, which also prevented ear and dermal thickening. Moreover, the tissue levels of the inflammatory cytokines and chemokines interleukin (IL)-10, IL-33, tumour necrosis factor-α, chemokine (C-C motif) ligand 2/monocyte chemoattractant protein-1 and chemokine (C-C motif) ligand 5/RANTES were significantly reduced after probiotic treatment, but only IL-33 and IL-10 were reduced when the mice were treated with acetate. These results show that B. longum 51A exerted a potential prophylactic effect on skin inflammation and that acetate represents one potential mechanism. However, other factors are likely involved since these two treatments do not yield the same results.

Evaluation of the reproductive profile of Subulina octona (Gastropoda, Subulinidae) experimentally infected by Paratanaisia bragai (Digenea, Eucotylidae).

Snails infected by trematodes may increase or decrease their reproductive activity in response to the presence of infection. Our aim was to verify the reproductive alterations in Subulina octona after infection by Paratanaisia bragai. The infected snails were individually exposed for 24 hours to 20 parasite eggs and four groups were formed (10, 20, 30 and 40 d.p.i.- days after infection), along with control groups. Every 10 days, the number of eggs in the reproductive tract, number of eggs hatched, galactogen content and histopathological changes were evaluated. The reproductive in the control and infected snails presented an alternating pattern, where periods of high production of eggs and newly hatched were followed by periods of low production. However, in relation to the amount of galactogen, both control and infected groups followed the same pattern of variation. In the histology, we observed the presence of male and female gametes with marked reduction in the number of oocytes. The results indicate that the intra-snail development of the parasite affects the reproductive biology of the host.

Effects of dietary fibre intake in chemotherapy-induced mucositis in murine model.

Mucositis is an inflammation of the gastrointestinal mucosa resulting from high doses of radio/chemotherapy treatment and may lead to interruption of antineoplasic therapy. Soluble fibres, like pectin, increase SCFA production, which play a role in gut homoeostasis and inflammation suppression. Due to the properties of pectin, the aim of the present study was to evaluate the effect of a high-fibre (HF) diet on chemotherapy-induced mucositis in a murine model. C57/BL6 mice received control (AIN93M), HF, low/zero fibre (LF) diets for 10 d prior to mucositis challenging with irinotecan (75 mg/kg), or they were treated with acetate added to drinking water 5 d prior to and during the mucositis induction. Mice that received the HF diet showed decreased immune cells influx and improved histopathological parameters in the intestine, compared with mice that received the normal diet. Furthermore, the HF diet decreased intestinal permeability induced in the mucositis model when compared with the control group. This effect was not observed for acetate alone, which did not improve gut permeability. For instance, mice that received the LF diet had worsened gut permeability, compared with mice that received the normal diet and mucositis. The effects of the HF and LF diets were shown to modulate the intestinal microbiota, in which the LF diet increased the levels of Enterobacteriaceae, a group associated with gut inflammation, whereas the HF diet decreased this group and increased Lactobacillus and Bifidobacterium (SCFA producers) levels. In conclusion, the results demonstrated the importance of dietary fibre intake in the modulation of gut microbiota composition and homoeostasis maintenance during mucositis in this model.

Saccharomyces boulardii as therapeutic alternative in experimental giardiasis.

AIMS: The objective of this study was to evaluate the effect of treatment with the probiotic Saccharomyces boulardii with or without metronidazole in experimental giardiasis. METHODS AND RESULTS: The effect of treatment with S. boulardii with or without metronidazole on the intestinal mucosa, the antioxidant defence system and the parasitic load was determined in experimental giardiasis. Eight groups of animals with infection and/or treatment with the probiotic and/or drugs for 1 week after infection with Giardia lamblia were used. A reduction of approximately 90% in the parasitic load was observed in all the treated groups. Saccharomyces boulardii attenuated the damage caused by infection in the intestinal mucosa preserving its architecture and inhibiting the oxidative stress induced by parasite and metronidazole. CONCLUSIONS: Saccharomyces boulardii was effective alone or in combination with metronidazole in resolving already established G. lamblia infection. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest the use of S. boulardii as an alternative treatment for giardiasis mainly in cases of resistance or intolerance to conventional treatment.