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1.
J Am Psychoanal Assoc ; : 30651241256650, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38864203

ABSTRACT

This paper presents a collaboration between a clinician (C.M.J.) and a research team (W.B., B.M., and S.M.) to address the question: At an operational level, what happens in the special form of conversation that is psychotherapy? How can we study, beyond a priori lenses of psychoanalytic models, what we are actually doing when we engage in this process? How can we capture from the linear flow of conversation, the simultaneous, complex, active, interwoven, dimensional emotion schemas that words can only point toward? To address the question, we first present the need for new approaches in the current climate within the clinical and research communities. Next, we address the challenges for clinicians and researchers by using multiple code theory and derived linguistic measures that offer an objective view of the processes of subjectivity. We then apply the research methods to the clinical data to illustrate the yield of the collaborative effort-a yield that captures the connection between the linear flow of words and the arousal, verbal expression, and reflection/integration of emotion schemas without the usual filters of psychoanalytic models of process and change. The project illustrates the critical value of clinicians' perspectives to guide researchers and encourages clinicians to participate in research to advance our field. For researchers, this project represents a "fourth generation" of process research that includes the criteria of video-recorded, transcribed data; the clinician's report of their experience; a theory of how emotion-laden meaning and motivations (emotion schemas) are expressed in the therapeutic conversation; and reliable, valid measures to capture and represent those processes; and that encourages researchers to access the rich contributions of clinicians' understanding. The implication for clinical practice is a new way to look beyond the lens of psychoanalytic models into what is actually unfolding in real time.

2.
Glob Chall ; 7(12): 2300030, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38094863

ABSTRACT

Employing new therapeutic indications for drugs that are already approved for human use has obvious advantages, including reduced costs and timelines, because some routine steps of drug development and regulation are not required. This work concentrates on the redirection of artemisinins (ARTS) that already are approved for clinical use, or investigated, for malaria treatment. Several mechanisms of action are suggested for ARTS, among which only a few have been successfully examined in vivo, mainly the induction of oxidant stress and anti-inflammatory effects. Despite these seemingly contradictory effects, ARTS are proposed for repurposing in treatment of inflammatory disorders and diverse types of diseases caused by viral, bacterial, fungal, and parasitic infections. When pathogens are treated the expected outcome is diminution of the causative agents and/or their inflammatory damage. In general, repurposing ARTS is successful in only a very few cases, specifically when a valid mechanism can be targeted using an additional therapeutic agent and appropriate drug delivery. Investigation of repurposing should include optimization of drug combinations followed by examination in relevant cell lines, organoids, and animal models, before moving to clinical trials.

3.
Biomedicines ; 11(9)2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37760981

ABSTRACT

Assessment of structure-activity relationships for anti-protozoan activity revealed a strategy for preparing potent anisomycin derivatives with reduced host toxicity. Thirteen anisomycin analogs were synthesized by modifying the alcohol, amine, and aromatic functional groups. Examination of anti-protozoal activity against various strains of Leishmania and cytotoxicity against leucocytes with comparison against the parent natural product demonstrated typical losses of activity with modifications of the alcohol, amine, and aromatic meta-positions. On the other hand, the para-phenol moiety of anisomycin proved an effective location for introducing substituents without significant loss of anti-protozoan potency. An entry point for differentiating activity against Leishmania versus host has been uncovered by this systematic study.

4.
Am J Trop Med Hyg ; 107(5): 996-998, 2022 11 14.
Article in English | MEDLINE | ID: mdl-36216319

ABSTRACT

Cutaneous leishmaniasis (CL) is endemic in Israel, caused mainly by Leishmania major (L. major) and L. tropica. In addition, returning travelers import another leishmanial species such as L. braziliensis. Although we are dealing with a skin disease, the blood bank in Israel does not accept blood donations from people infected with CL in cases of multiple lesions due to the possibility of transfusion. Our purpose was to investigate the prevalence of Leishmania in the blood of patients with active or previous CL. This pilot study screened patients with active or previous CL for parasites in their blood. All patients were infected in Israel or were returning travelers with leishmaniasis acquired in Latin America. Patients were seen at the Sheba Medical Center. In addition, patients were seen at their homes in L. tropica and L. major endemic regions in Israel. Blood samples were taken from each patient for culture and polymerase chain reaction (PCR). Altogether 62 blood samples were examined (L. tropica = 26, L. major = 33, and L. braziliensis = 3). Twenty-seven patients had an active disease and 35 were recovered. All blood cultures and PCR were negative for parasites except one blood sample that was PCR positive for L. braziliensis. The findings of our study, although a small sample, suggest that people with active or recent CL caused by L. major and L. tropica, do not harbor parasites in their blood. Thus, their exclusion from blood donation should be revisited. Further studies are needed with larger sample size and highly sensitive tests.


Subject(s)
Leishmania major , Leishmania tropica , Leishmaniasis, Cutaneous , Humans , Blood Donors , Pilot Projects , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/parasitology
5.
JAMIA Open ; 5(4): ooac077, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36247086

ABSTRACT

Objective: Understanding the current state of real-world Fast Healthcare Interoperability Resources (FHIR) applications (apps) will benefit biomedical research and clinical care and facilitate advancement of the standard. This study aimed to provide a preliminary assessment of these apps' clinical, technical, and implementation characteristics. Materials and Methods: We searched public repositories for potentially eligible FHIR apps and surveyed app implementers and other stakeholders. Results: Of the 112 apps surveyed, most focused on clinical care (74) or research (45); were implemented across multiple sites (56); and used SMART-on-FHIR (55) and FHIR version R4 (69). Apps were primarily stand-alone web-based (67) or electronic health record (EHR)-embedded (51), although 49 were not listed in an EHR app gallery. Discussion: Though limited in scope, our results show FHIR apps encompass various domains and characteristics. Conclusion: As FHIR use expands, this study-one of the first to characterize FHIR apps at large-highlights the need for systematic, comprehensive methods to assess their characteristics.

6.
BMC Infect Dis ; 22(1): 212, 2022 Mar 03.
Article in English | MEDLINE | ID: mdl-35241005

ABSTRACT

BACKGROUND: We report a clinically challenging and unusual case of L. donovani oral mucosal leishmaniasis. CASE PRESENTATION: Israeli resident with a former travel to central and North Africa, with no documented or prior cutaneous lesions presented with oral lesions of the maxillary gingiva and the upper lip. A delay in diagnosis and treatment have led to progression of the maxillary gingival lesions towards the hard palatal and the soft palate that could have potentially compromised the upper airway. CONCLUSIONS: This case highlights the importance of early diagnosis of leishmaniasis in patients with oral lesions and the laboratory workup necessary to appropriately characterize and treat the disease.


Subject(s)
Leishmaniasis, Cutaneous , Leishmaniasis, Mucocutaneous , Leishmaniasis , Oral Ulcer , Humans , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/pathology , Leishmaniasis, Mucocutaneous/diagnosis , Leishmaniasis, Mucocutaneous/drug therapy , Lip/pathology , Mouth Mucosa
7.
Wellcome Open Res ; 6: 168, 2021.
Article in English | MEDLINE | ID: mdl-34693027

ABSTRACT

Background: Leishmaniasis is a globally important yet neglected parasitic disease transmitted by phlebotomine sand flies. With new candidate vaccines in or near the clinic, a controlled human challenge model (CHIM) using natural sand fly challenge would provide a method for early evaluation of prophylactic efficacy. Methods : We evaluated the biting frequency and adverse effects resulting from exposure of human volunteers to bites of either Phlebotomus papatasi or P. duboscqi, two natural vectors of Leishmania major. 12 healthy participants were recruited (mean age 40.2 ± 11.8 years) with no history of significant travel to regions where L. major-transmitting sand flies are prevalent. Participants were assigned to either vector by 1:1 allocation and exposed to five female sand flies for 30 minutes in a custom biting chamber. Bite frequency was recorded to confirm a bloodmeal was taken. Participant responses and safety outcomes were monitored using a visual analogue scale (VAS), clinical examination, and blood biochemistry. Focus groups were subsequently conducted to explore participant acceptability. Results: All participants had at least one successful sand fly bite with none reporting any serious adverse events, with median VAS scores of 0-1/10 out to day 21 post-sand fly bite. Corresponding assessment of sand flies confirmed that for each participant at least 1/5 sand flies had successfully taken a bloodmeal (overall mean 3.67±1.03 bites per participant). There was no significant difference between P. papatasi and P. duboscqi in the number of bites resulting from 5 sand flies applied to human participants (3.3±0.81 vs 3.00±1.27 bites per participant; p=0.56) .  In the two focus groups (n=5 per group), themes relating to positive participant-reported experiences of being bitten and the overall study, were identified. Conclusions: These results validate a protocol for achieving successful sand fly bites in humans that is safe, well-tolerated and acceptable for participants. Clinicaltrials.gov registration: NCT03999970 (27/06/2019).

8.
Nat Commun ; 12(1): 215, 2021 01 11.
Article in English | MEDLINE | ID: mdl-33431825

ABSTRACT

Leishmaniasis is widely regarded as a vaccine-preventable disease, but the costs required to reach pivotal Phase 3 studies and uncertainty about which candidate vaccines should be progressed into human studies significantly limits progress in vaccine development for this neglected tropical disease. Controlled human infection models (CHIMs) provide a pathway for accelerating vaccine development and to more fully understand disease pathogenesis and correlates of protection. Here, we describe the isolation, characterization and GMP manufacture of a new clinical strain of Leishmania major. Two fresh strains of L. major from Israel were initially compared by genome sequencing, in vivo infectivity and drug sensitivity in mice, and development and transmission competence in sand flies, allowing one to be selected for GMP production. This study addresses a major roadblock in the development of vaccines for leishmaniasis, providing a key resource for CHIM studies of sand fly transmitted cutaneous leishmaniasis.


Subject(s)
Leishmania major/physiology , Leishmaniasis, Cutaneous/parasitology , Animals , Disease Models, Animal , Humans , Insect Vectors/parasitology , Israel , Leishmania major/genetics , Leishmania major/growth & development , Leishmaniasis, Cutaneous/transmission , Mice, Inbred BALB C , Parasites/genetics , Phylogeny , Psychodidae/parasitology , Whole Genome Sequencing
9.
Elife ; 92020 03 25.
Article in English | MEDLINE | ID: mdl-32209228

ABSTRACT

Protozoan parasites of the Leishmania donovani complex - L. donovani and L. infantum - cause the fatal disease visceral leishmaniasis. We present the first comprehensive genome-wide global study, with 151 cultured field isolates representing most of the geographical distribution. L. donovani isolates separated into five groups that largely coincide with geographical origin but vary greatly in diversity. In contrast, the majority of L. infantum samples fell into one globally-distributed group with little diversity. This picture is complicated by several hybrid lineages. Identified genetic groups vary in heterozygosity and levels of linkage, suggesting different recombination histories. We characterise chromosome-specific patterns of aneuploidy and identified extensive structural variation, including known and suspected drug resistance loci. This study reveals greater genetic diversity than suggested by geographically-focused studies, provides a resource of genomic variation for future work and sets the scene for a new understanding of the evolution and genetics of the Leishmania donovani complex.


Subject(s)
Genetic Variation , Genome, Protozoan , Leishmania donovani/genetics , Aneuploidy , Animals , DNA Copy Number Variations , Drug Resistance/genetics , Evolution, Molecular , Heterozygote , Polymorphism, Single Nucleotide , Selection, Genetic
10.
Emerg Infect Dis ; 25(4): 642-648, 2019 04.
Article in English | MEDLINE | ID: mdl-30882319

ABSTRACT

Mucosal leishmaniasis (ML) is a complication of New World cutaneous leishmaniasis (CL) caused mainly by Leishmania (Viannia) braziliensis. This retrospective study investigated all cases of ML caused by L. (V.) braziliensis in a tertiary medical center in Israel, evaluating the risk factors, clinical presentations, diagnosis, treatment, and outcome of mucosal involvement in ML caused by L. (V.) braziliensis in travelers returning to Israel. During 1993-2015, a total of 145 New World CL cases were seen in travelers returning from Bolivia; among them, 17 (11.7%) developed ML. Nasopharyngeal symptoms developed 0-3 years (median 8 months) after exposure. The only significant risk factor for developing ML was the absence of previous systemic treatment. Among untreated patients, 41% developed ML, compared with only 3% of treated patients (p = 0.005). Systemic treatment for CL seems to be a protective factor against developing ML.


Subject(s)
Communicable Diseases, Imported , Leishmania braziliensis , Leishmaniasis, Mucocutaneous/transmission , Adult , Bolivia , Communicable Diseases, Imported/prevention & control , Communicable Diseases, Imported/transmission , Diagnosis, Differential , Female , Humans , Israel , Leishmania braziliensis/isolation & purification , Leishmaniasis, Mucocutaneous/diagnosis , Leishmaniasis, Mucocutaneous/prevention & control , Leishmaniasis, Mucocutaneous/therapy , Male , Pathology, Molecular , Retrospective Studies , Risk Factors , Skin Diseases, Parasitic , Travel-Related Illness
11.
Drug Deliv Transl Res ; 9(1): 76-84, 2019 02.
Article in English | MEDLINE | ID: mdl-30484256

ABSTRACT

Cutaneous leishmaniasis (CL) is an infectious, parasitic disease caused by the protozoan Leishmania. Amphotericin B (AMB) is a macrolide polyene antibiotic presenting potent antifungal and antileishmanial activity, but due to poor water solubility at physiological pH, side effects, and toxicity, its therapeutic efficiency is limited. In the present study, poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) loaded with AMB were generated to reduce drug toxicity and facilitate localized delivery over a prolonged time. AMB NPs were characterized for particle size, zeta potential, polydispersity index, and degree of aggregation. In vitro assessments demonstrated its sustained activity against Leishmania major promastigotes and parasite-infected macrophages. A single intralesional administration to infected BALB/c mice revealed that AMB NPs were more effective than AMB deoxycholate in terms of reducing lesion area. Taken together, these findings suggest that AMB NPs improve AMB delivery and can be used for local treatment of CL.


Subject(s)
Amphotericin B/administration & dosage , Antiprotozoal Agents/administration & dosage , Leishmania major/drug effects , Leishmaniasis, Cutaneous/drug therapy , Polyesters/chemistry , Polyglycolic Acid/chemistry , Administration, Topical , Amphotericin B/chemistry , Amphotericin B/pharmacology , Animals , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/pharmacology , Disease Models, Animal , Drug Carriers/chemistry , Humans , Mice , Mice, Inbred BALB C , Nanoparticles , Particle Size , THP-1 Cells
12.
Int J Parasitol Drugs Drug Resist ; 8(3): 403-410, 2018 12.
Article in English | MEDLINE | ID: mdl-30173105

ABSTRACT

Leishmania infantum is one of the causative agents of visceral leishmaniasis (VL), a widespread, life-threatening disease. This parasite is responsible for the majority of human VL cases in Brazil, the Middle East, China, Central Asia and the Mediterranean basin. Its main reservoir are domestic dogs which, similar to human patients, may develop severe visceral disease and die if not treated. The drug allopurinol is used for the long-term maintenance of dogs with canine leishmaniasis. Following our report of allopurinol resistance in treated relapsed dogs, we investigated the mechanisms and markers of resistance to this drug. Whole genome sequencing (WGS) of clinical resistant and susceptible strains, and laboratory induced resistant parasites, was carried out in order to detect genetic changes associated with resistance. Significant gene copy number variation (CNV) was found between resistant and susceptible isolates at several loci, including a locus on chromosome 30 containing the genes LinJ.30.3550 through LinJ.30.3580. A reduction in copy number for LinJ.30.3560, encoding the S-adenosylmethionine synthetase (METK) gene, was found in two resistant clinical isolates and four induced resistant clonal strains. Using quantitative real time PCR, this reduction in METK copy number was also found in three additional resistant clinical isolates. Furthermore, inhibition of S-adenosylmethionine synthetase encoded by the METK gene in allopurinol susceptible strains resulted in increased allopurinol resistance, confirming its role in resistance to allopurinol. In conclusion, this study identified genetic changes associated with L. infantum resistance to allopurinol and the reduction in METK copy number identified may serve as a marker for resistance in dogs, and reduced protein activity correlated with increased allopurinol resistance.


Subject(s)
Allopurinol/pharmacology , DNA Copy Number Variations/drug effects , Drug Resistance/genetics , Gene Dosage/drug effects , Leishmania infantum/drug effects , Leishmania infantum/genetics , Methionine Adenosyltransferase/genetics , Animals , Dog Diseases/drug therapy , Dogs , Humans , Leishmania infantum/enzymology , Leishmaniasis/drug therapy , Leishmaniasis/parasitology , Leishmaniasis/veterinary , Leishmaniasis, Visceral/drug therapy , Real-Time Polymerase Chain Reaction , Whole Genome Sequencing
13.
Infect Genet Evol ; 65: 80-90, 2018 11.
Article in English | MEDLINE | ID: mdl-30016714

ABSTRACT

Visceral leishmaniasis (VL), the most severe form of leishmaniasis, is caused by Leishmania donovani. In addition to fatal VL, these parasites also cause skin diseases in immune-competent and -suppressed people, post-kala azar dermal leishmaniasis (PKDL) and HIV/VL co-infections, respectively. Genetic polymorphism in 36 Ethiopian and Sudanese L. donovani strains from VL, PKDL and HIV/VL patients was examined using Amplified Fragment Length Polymorphism (AFLP), kDNA minicircle sequencing and Southern blotting. Strains were isolated from different patient tissues: in VL from lymph node, spleen or bone marrow; and in HIV/VL from skin, spleen or bone marrow. When VL and PKDL strains from the same region in Sudan were examined by Southern blotting using a DNA probe to the L. donovani 28S rRNA gene only minor differences were observed. kDNA sequence analysis distributed the strains in no particular order among four clusters (A - D), while AFLP analysis grouped the strains according to geographical origin into two major clades, Southern Ethiopia (SE) and Sudan/Northern Ethiopia (SD/NE). Strains in the latter clade were further divided into subpopulations by zymodeme, geography and year of isolation, but not by clinical symptoms. However, skin isolates showed significantly (p < 0.0001) fewer polymorphic AFLP fragments (average 10 strains = 348.6 ±â€¯8.1) than VL strains (average 26 strains = 383.5 ±â€¯3.8).


Subject(s)
DNA, Kinetoplast/genetics , DNA, Protozoan , Leishmania donovani/physiology , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/parasitology , Polymorphism, Genetic , Tropism , Africa, Eastern/epidemiology , Amplified Fragment Length Polymorphism Analysis , Genotyping Techniques , Geography , High-Throughput Nucleotide Sequencing , Humans , Public Health Surveillance
14.
PLoS Genet ; 14(1): e1007133, 2018 01.
Article in English | MEDLINE | ID: mdl-29315303

ABSTRACT

Leishmania donovani is the main cause of visceral leishmaniasis (VL) in East Africa. Differences between northern Ethiopia/Sudan (NE) and southern Ethiopia (SE) in ecology, vectors, and patient sensitivity to drug treatment have been described, however the relationship between differences in parasite genotype between these two foci and phenotype is unknown. Whole genomic sequencing (WGS) was carried out for 41 L. donovani strains and clones from VL and VL/HIV co-infected patients in NE (n = 28) and SE (n = 13). Chromosome aneuploidy was observed in all parasites examined with each isolate exhibiting a unique karyotype. Differences in chromosome ploidy or karyotype were not correlated with the geographic origin of the parasites. However, correlation between single nucleotide polymorphism (SNP) and geographic origin was seen for 38/41 isolates, separating the NE and SE parasites into two large groups. SNP restricted to NE and SE groups were associated with genes involved in viability and parasite resistance to drugs. Unique copy number variation (CNV) were also associated with NE and SE parasites, respectively. One striking example is the folate transporter (FT) family genes (LdBPK_100390, LdBPK_100400 and LdBPK_100410) on chromosome 10 that are single copy in all 13 SE isolates, but either double copy or higher in 39/41 NE isolates (copy number 2-4). High copy number (= 4) was also found for one Sudanese strain examined. This was confirmed by quantitative polymerase chain reaction for LdBPK_100400, the L. donovani FT1 transporter homolog. Good correlation (p = 0.005) between FT copy number and resistance to methotrexate (0.5 mg/ml MTX) was also observed with the haploid SE strains examined showing higher viability than the NE strains at this concentration. Our results emphasize the advantages of whole genome analysis to shed light on vital parasite processes in Leishmania.


Subject(s)
DNA, Protozoan/genetics , Genome, Protozoan/genetics , Leishmania donovani/genetics , Whole Genome Sequencing/methods , Aneuploidy , Animals , DNA Copy Number Variations , DNA, Protozoan/chemistry , Ethiopia , Genotype , Geography , Humans , Karyotype , Leishmania donovani/classification , Leishmania donovani/physiology , Leishmaniasis, Visceral/parasitology , Phylogeny , Polymorphism, Single Nucleotide
15.
Am J Trop Med Hyg ; 98(1): 139-141, 2018 01.
Article in English | MEDLINE | ID: mdl-29141753

ABSTRACT

Leishmania spp. are medically important unicellular parasites transmitted by phlebotomine sand flies. The World Health Organization recently highlighted the importance of reliable diagnostic tools for leishmaniasis. Our study of human infection was conducted in two endemic foci of Leishmania tropica in the Galilee region, northern Israel. Elevated anti-Leishmania antibodies were present in the majority (78.6%) of L. tropica-PCR positive individuals. Moreover, the enzyme-linked immunosorbent assay showed high sensitivity, specificity, and negative and positive predictive values (ranging between 73% and 79%), thus fulfilling the basic requirement for future development of a serodiagnostic and screening tool. The anti-sand fly saliva antibodies used as biomarkers of exposure reflected the composition of the local sand fly fauna as well as the abundance of individual species. High levels of antibodies against vector salivary proteins may further indicate frequent exposure to sand flies and consequently a higher probability of Leishmania transmission.


Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous/diagnosis , Animals , Enzyme-Linked Immunosorbent Assay/methods , Humans , Israel/epidemiology , Leishmaniasis, Cutaneous/epidemiology , Psychodidae/parasitology , Sensitivity and Specificity , Seroepidemiologic Studies , Serologic Tests/methods
16.
Nat Commun ; 8(1): 1589, 2017 11 17.
Article in English | MEDLINE | ID: mdl-29150609

ABSTRACT

Leishmania is a single-celled eukaryotic parasite afflicting millions of humans worldwide, with current therapies limited to a poor selection of drugs that mostly target elements in the parasite's cell envelope. Here we determined the atomic resolution electron cryo-microscopy (cryo-EM) structure of the Leishmania ribosome in complex with paromomycin (PAR), a highly potent compound recently approved for treatment of the fatal visceral leishmaniasis (VL). The structure reveals the mechanism by which the drug induces its deleterious effects on the parasite. We further show that PAR interferes with several aspects of cytosolic translation, thus highlighting the cytosolic rather than the mitochondrial ribosome as the primary drug target. The results also highlight unique as well as conserved elements in the PAR-binding pocket that can serve as hotspots for the development of novel therapeutics.


Subject(s)
Leishmania/metabolism , Paromomycin/metabolism , Ribosomes/metabolism , Amino Acid Sequence , Base Sequence , Binding Sites/genetics , Cryoelectron Microscopy , Cytosol/drug effects , Cytosol/metabolism , Humans , Leishmania/genetics , Leishmania/ultrastructure , Models, Molecular , Paromomycin/chemistry , Paromomycin/pharmacology , Protein Biosynthesis/drug effects , RNA, Ribosomal/chemistry , RNA, Ribosomal/metabolism , Ribosomal Proteins/chemistry , Ribosomal Proteins/metabolism , Ribosomes/chemistry , Ribosomes/ultrastructure , Sequence Homology, Amino Acid
17.
PLoS Negl Trop Dis ; 11(9): e0005910, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28892476

ABSTRACT

Resistance to allopurinol in zoonotic canine leishmaniasis has been recently shown to be associated with disease relapse in naturally-infected dogs. However, information regarding the formation of resistance and its dynamics is lacking. This study describes the successful in-vitro induction of allopurinol resistance in Leishmania infantum cultured under increasing drug pressure. Allopurinol susceptibility and growth rate of induced parasites were monitored over 23 weeks and parasite clones were tested at selected time points and compared to their parental lines, both as promastigotes and as amastigotes. Allopurinol resistance was formed in strains from two parasite stocks producing a 20-fold rise in IC50 along three distinct growth phases. In addition, characteristic differential clustering of single nucleotide polymorphisms (SNP) was found in drug sensitive and resistant parasite clones. Results confirm that genetic polymorphism, as well as clonal heterogeneity, contribute to in-vitro resistance to allopurinol, which is likely to occur in natural infection.


Subject(s)
Allopurinol/pharmacology , Antiprotozoal Agents/pharmacology , Dog Diseases/parasitology , Leishmania infantum/drug effects , Leishmaniasis, Visceral/veterinary , Allopurinol/administration & dosage , Animals , Dog Diseases/drug therapy , Dogs , Drug Resistance , Inhibitory Concentration 50 , Leishmania infantum/genetics , Leishmania infantum/growth & development , Leishmania infantum/isolation & purification , Leishmaniasis, Visceral/drug therapy , Leishmaniasis, Visceral/parasitology , Polymorphism, Single Nucleotide
18.
Int J Parasitol ; 47(10-11): 609-616, 2017 09.
Article in English | MEDLINE | ID: mdl-28455239

ABSTRACT

Visceral leishmaniasis (VL) is a potentially lethal, sand fly-borne disease caused by protozoan parasites belonging to the Leishmania donovani species complex. There are several adequate methods for diagnosing VL, but the majority of infected individuals remain asymptomatic, comprising potential parasite reservoirs for transmission of the disease. The gold standard for assessing host infectiousness to biting vector insects is xenodiagnosis (i.e. scoring infection rates among insectary-reared insects that had fed on humans suspected of being infected). However, when it comes to sand flies and leishmaniasis, xenodiagnosis is an intricate operation burdened by logistical hurdles and ethical concerns that prevent its effective application for mass screening of widely dispersed communities, particularly in rural regions of underdeveloped countries. Minimally invasive microbiopsy (MB) devices were designed to penetrate the skin to a depth of ∼200µm and absorb blood as well as skin cell lysates, mimicking the mode by which phlebotomine sand flies acquire blood meals, as well as their composition. MBs taken from 137 of 262 volunteers, living in endemic VL foci in Ethiopia, detected Leishmania parasites that could potentially be imbibed by feeding sand flies. Although the volume of MBs was 10-fold smaller than finger-prick blood samples, Leishmania DNA detection rates from MBs were significantly higher, implying that skin, more often than blood, was the source of parasites. Volunteers with histories of VL were almost as likely as healthy volunteers to test positive by MBs (southern Ethiopian focus: 95% CI: 0.35-2.59, P=1.0. northern Ethiopian focus 0.87: 95% CI: 0.22-3.76, P=1), suggesting the importance of asymptomatic patients as reservoirs of L. donovani. Minimally invasive, painless MBs should be considered for reliably and efficiently evaluating both L. donovani infection rates among large numbers of asymptomatic carriers and their infectiousness to blood-feeding sand flies.


Subject(s)
Leishmania donovani/isolation & purification , Leishmaniasis, Visceral/pathology , Animals , Biopsy/methods , Carrier State , DNA, Protozoan/isolation & purification , Ethiopia/epidemiology , Humans , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/parasitology , Parasitemia , Skin/parasitology
19.
PLoS Negl Trop Dis ; 11(4): e0005538, 2017 04.
Article in English | MEDLINE | ID: mdl-28403153

ABSTRACT

Turkey is located in an important geographical location, in terms of the epidemiology of vector-borne diseases, linking Asia and Europe. Cutaneous leishmaniasis (CL) is one of the endemic diseases in a Turkey and according to the Ministry Health of Turkey, 45% of CL patients originate from Sanliurfa province located in southeastern Turkey. Herein, the epidemiological status of CL, caused by L. tropica, in Turkey was examined using multilocus microsatellite typing (MLMT) of strains obtained from Turkish and Syrian patients. A total of 38 cryopreserved strains and 20 Giemsa-stained smears were included in the present study. MLMT was performed using 12 highly specific microsatellite markers. Delta K (ΔK) calculation and Bayesian statistics were used to determine the population structure. Three main populations (POP A, B and C) were identified and further examination revealed the presence of three subpopulations for POP B and C. Combined analysis was performed using the data of previously typed L. tropica strains and Mediterranean and Sanliurfa populations were identified. This finding suggests that the epidemiological status of L. tropica is more complicated than expected when compared to previous studies. A new population, comprised of Syrian L. tropica samples, was reported for the first time in Turkey, and the data presented here will provide new epidemiological information for further studies.


Subject(s)
Leishmania tropica/isolation & purification , Leishmaniasis, Cutaneous/epidemiology , Microsatellite Repeats , Azure Stains , Bayes Theorem , DNA, Protozoan/isolation & purification , Genetic Variation , Geographic Mapping , Humans , Leishmania tropica/classification , Multilocus Sequence Typing , Phylogeny , Syria/epidemiology , Turkey/epidemiology
20.
J Am Med Inform Assoc ; 24(5): 882-890, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28339791

ABSTRACT

BACKGROUND: It is critical to integrate and analyze data from biological, translational, and clinical studies with data from health systems; however, electronic artifacts are stored in thousands of disparate systems that are often unable to readily exchange data. OBJECTIVE: To facilitate meaningful data exchange, a model that presents a common understanding of biomedical research concepts and their relationships with health care semantics is required. The Biomedical Research Integrated Domain Group (BRIDG) domain information model fulfills this need. Software systems created from BRIDG have shared meaning "baked in," enabling interoperability among disparate systems. For nearly 10 years, the Clinical Data Standards Interchange Consortium, the National Cancer Institute, the US Food and Drug Administration, and Health Level 7 International have been key stakeholders in developing BRIDG. METHODS: BRIDG is an open-source Unified Modeling Language-class model developed through use cases and harmonization with other models. RESULTS: With its 4+ releases, BRIDG includes clinical and now translational research concepts in its Common, Protocol Representation, Study Conduct, Adverse Events, Regulatory, Statistical Analysis, Experiment, Biospecimen, and Molecular Biology subdomains. INTERPRETATION: The model is a Clinical Data Standards Interchange Consortium, Health Level 7 International, and International Standards Organization standard that has been utilized in national and international standards-based software development projects. It will continue to mature and evolve in the areas of clinical imaging, pathology, ontology, and vocabulary support. BRIDG 4.1.1 and prior releases are freely available at https://bridgmodel.nci.nih.gov .


Subject(s)
Biomedical Research , Health Information Interoperability/standards , Semantic Web , Semantic Web/standards , Software , Terminology as Topic
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