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Background: Tuberculosis (TB) is a major public health concern in Ecuador and Peru, both settings of high burden of drug resistance TB. Molecular epidemiology tools are important to understand the transmission dynamics of Mycobacterium tuberculosis Complex (MTBC) and to track active transmission clusters of regional importance. This study is the first to address the transmission of TB between Peru and Ecuador through the population structure of MTBC lineages circulating in the Ecuadorian border province of ''El Oro''. Methods: A total number of 56 MTBC strains from this province for years 2012–2015 were included in the study and analyzed by 24-loci MIRU-VNTR and spoligotyping. Results: Genotyping revealed a high degree of diversity for MTBC in ''El Oro'', without active transmission clusters. MTBC L4 was predominant, with less than 2% of strains belonging to MTBC L2-Beijing. Conclusions: These results may suggest that TB dynamics in this rural and semi-urban area would not be linked to highly transmitted strains like MTBC L2-Beijing from Peru, but related to TB relapse; although further studies with larger MTBC cultures collection from recent years are needed. Nevertheless, we recommend to reinforce TB surveillance programs in remote rural settings and border regions in Ecuador.

IntroductionA major sublineage within the Mycobacterium tuberculosis (MTB) LAM family characterized by a new in-frame fusion gene Rv3346c/55c was discovered in Rio de Janeiro (Brazil) in 2007, called RDRio, associated to drug resistance. The few studies about prevalence of MTB RDRio strains in Latin America reported values ranging from 3% in Chile to 69.8% in Venezuela, although no information is available for countries like Ecuador.MethodsA total of 814 MTB isolates from years 2012 to 2016 were screened by multiplex PCR for RDRio identification, followed by 24-loci MIRU-VNTR and spoligotyping.ResultsA total number of 17 MTB RDRio strains were identified, representing an overall prevalence of 2.09% among MTB strains in Ecuador. While 10.9% of the MTB isolates included in the study were multidrug resistance (MDR), 29.4% (5/17) of the RDRio strains were MDR.DiscussionThis is the first report of the prevalence of MTB RDRio in Ecuador, where a strong association with MDR was found, but also a very low prevalence compared to other countries in Latin America. It is important to improve molecular epidemiology tools as a part of MTB surveillance programs in Latin America to track the transmission of potentially dangerous MTB stains associated to MDR TB like MTB RDRio.

Infections caused by mycobacteria, including Mycobacterium tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM), are a major public health issue worldwide. An accurate diagnosis of mycobacterial species is a challenge for surveillance and treatment, particularly in high-burden settings usually associated with low- and middle-income countries. In this study, we analyzed the clinical performance of two commercial PCR kits designed for the identification and differentiation of MTBC and NTM, available in a high-burden setting such as Ecuador. A total of 109 mycobacteria isolates were included in the study, 59 of which were previously characterized as M. tuberculosis and the other 59 as NTM. Both kits displayed great clinical performance for the identification of M. tuberculosis, with 100% sensitivity. On the other hand, for NTM, one of the kits displayed a good clinical performance with a sensitivity of 94.9% (CI 95%: 89–100%), while the second kit had a reduced sensitivity of 77.1% (CI 95%: 65–89%). In conclusion, one of the kits is a fast and reliable tool for the identification and discrimination of MTBC and NTM from clinical isolates.

ObjectiveTuberculosis (TB) is a major public health concern in Ecuador and Colombia, considering that both countries are high-burden TB settings. Molecular epidemiology is crucial to understand the transmission dynamics of Mycobacterium tuberculosis complex (MTBC) and to identify active transmission clusters of regional importance.MethodsWe studied the potential transmission of TB between Colombia and Ecuador through the analysis of the population structure of MTBC lineages circulating in the Ecuadorian province of Esmeraldas at the border with Colombia. A total of 105 MTBC strains were characterized by 24-loci MIRU-VNTR and spoligotyping.ResultsMTBC lineage 4 is only present in Esmeraldas; no MTBC strains belonging to Lineage 2–sublineage Beijing were found despite its presence in other provinces of Ecuador and, in Colombia. Genotyping results revealed a high degree of diversity for MTBC in Esmeraldas: Neither active transmission clusters within this province nor including MTBC strains from Colombia or other provinces of Ecuador were found.ConclusionOur data suggest that tuberculosis dynamics in this rural and isolated area may be not related to highly transmitted strains but could be influenced by other health determinants that favor TB relapse such as poverty and poor health system access. Further studies including a larger number of MTBC strains from Esmeraldas are necessary to test this hypothesis.

Ecuador had substantial COVID-19-mortality during 2020 despite early implementation of non-pharmaceutical interventions (NPIs). Resource-limited settings like Ecuador have high proportions of informal labour which entail high human mobility, questioning efficacy of NPIs. We performed a retrospective observational study in Ecuador’s national reference laboratory for viral respiratory infections during March 2020–February 2021 using stored respiratory specimens from 1950 patients, corresponding to 2.3% of all samples analysed within the Ecuadorian national surveillance system per week. During 2020, detection of SARS-CoV-2 (Pearson correlation; r = −0.74; p = 0.01) and other respiratory viruses (Pearson correlation; r = −0.68; p = 0.02) by real-time RT–PCR correlated negatively with NPIs stringency. Among respiratory viruses, adenoviruses (Fisher’s exact-test; p = 0.026), parainfluenzaviruses (p = 0.04), enteroviruses (p

Objectives: Several cases of reverse transmission of SARS-CoV-2 from human to pets were reported during the first year of the COVID-19 pandemic. Accordingly, the World Organization for Animal Health has recommended to improve SARS-CoV-2 surveillance on household animals to assess the risk of transmission between species. After such recommendation, we studied the potential SARS-CoV-2 infection in household dogs and cats in the city of Guayaquil, the most populated city in Ecuador. Methods: Oral and nasal swab samples were collected from dogs and cats within 10 days of a positive SARS-CoV-2 test result of their owners. Total ribonucleic acid was extracted and detection of viral gene targets N and ORF1ab was performed by quantitative reverse transcription polymerase chain reaction. Results: From the 50 cats and dogs tested, 12 were SARS-CoV-2 positive, giving a total positivity rate of 24%. A total of 1 of 8 cats tested positive, whereas 11 of 42 dogs were positive, yielding a positivity rate of 12.5% and 26.2%, respectively. SARS-CoV-2 was confirmed by whole genome sequencing. In addition, we also found a statistically significant association between SARS-CoV-2 pet positivity and food sharing with infected owners. Conclusion: This study is the second active surveillance of SARS-CoV-2 in household dogs and cats in Latin America. Moreover, it is the first study to address the risk factors associated with potential anthropogenic SARS-CoV-2 transmission to domestic cats and dogs. Given the high presence of free-roaming dogs and cats in rural and urban areas in Latin American countries and the high capacity shown by coronaviruses for interspecies transmission, our findings support the view that SARS-CoV-2 surveillance in pets is necessary to better understand the role that pet-human interaction plays in the COVID-19 spread.

Rabies is a viral zoonotic disease that can infect all mammals and the main route of transmission to human is attributed to dog bites. Due to the limited information available about the rabies vaccination coverage, although Ecuador is supposed to be free of rabies, we conducted a retrospective study of the epidemiological surveillance records on the notification of dog attacks to humans in Guayaquil, the most populated city in Ecuador. The results showed an annual incidence rate of 105.6 dog bites per 100,000 inhabitants, where the most affected anatomical parts are the lower extremities; individuals from 1 to 14 years of age were the most affected age group (IC95% 1.42–1.92; p

Canine Distemper Virus (CDV) is a highly contagious virus that can cross mammalian species barriers and has widespread impacts on both domestic animals and wildlife populations. This study describes a recent outbreak of CDV in the Galapagos Islands in 2019. A total number of 125 dogs with clinical signs compatible with CDV were included in this study. Nasal swabs were taken and analyzed by RT-qPCR for the detection of CDV, resulting in a positivity rate of 74.4% (IC95%, 66–81%). Among the CDV positive dogs, 82.2% presented with respiratory signs, 48.8% neurological signs, and 28.9% gastrointestinal signs. CDV has been previously reported in the domestic canine population of the Galapagos Islands in 2001 and 2004. The current study shows how CDV is still a threat for the endemic and endangered Galapagos sea lion, despite recent policies for dog population control and CDV vaccination.

During the ongoing COVID-19 pandemic, there were several reports of SARS-CoV-2 transmission from human to animals, mostly to companion cats and dogs but also to free ranging wild species like minks and deers. Under this scenario, SARS-CoV-2 surveillance in domestic animals to assess the risk of transmission between species have been suggested by the OIE. Here we present a case report of SARS-CoV-2 infection in free roaming dogs, found at a rural indigenous community from the Ecuadorian Amazonia. Oral and nasal swabs samples were collected from three dogs found during a COVID-19 surveillance intervention in Amazonian indigenous communities where severe COVID-19 outbreaks were suspected. Total RNA was extracted from dog samples and detection of SARS-CoV-2 gene targets N, ORF1ab and S was performed. The three dogs tested positive for at least two SARS-CoV-2 viral targets. Moreover, there was a high SARS-CoV-2 infection rate of 87.2% within this community. Given that 17.1% of SARS-CoV-2 positive individuals had an ultra high load greater than 108 copies/ml, transmission from humans to dogs likely occurred. To our knowledge, this study is the first report of SARS-CoV-2 positive free roaming dogs. Also, as those animals were found in the Amazonian forest, SARS-CoV-2 transmission to wild mammals is a potential concern. Given the high presence of free roaming dogs associated to rural and indigenous communities in South America, the potential role of these domestic animals on COVID-19 spread would deserve further surveillance studies involving SARS-CoV-2 detection by PCR and molecular epidemiology based on genome sequencing to confirm human to dog transmission.

The location of Ecuador—an equatorial nation—favors the multiplication and dispersal of the Leptospira genus both on the Pacific Coast and in the Amazon tropical ecoregions. Nevertheless, leptospirosis epidemiology has not been fully addressed, even though the disease has been recognized as a significant public health problem in the country. The purpose of this literature review is to update knowledge on the epidemiology and geographical distribution of Leptospira spp. and leptospirosis in Ecuador to target future research and develop a national control strategy. A retrospective literature search using five international, regional, and national databases on Leptospira and leptospirosis including humans, animals, and environmental isolations of the bacteria and the disease incidence in Ecuador published between 1919 and 2022 (103 years) with no restriction on language or publication date was performed. We found and analyzed 47 publications including 22 of humans, 19 of animals, and two of the environments; three of these covered more than one of these topics, and one covered all three (i.e., One Health). Most (60%) of the studies were conducted in the Coastal ecoregion. Twenty-four (51%) were published in international journals, and 27 (57%) were in Spanish. A total of 7342 human and 6314 other animal cases were studied. Leptospirosis was a frequent cause of acute undifferentiated febrile illness in the Coast and Amazon and was associated with rainfall. All three major clusters of Leptospira—pathogenic, intermediate, and saprophytic—were identified from both healthy and febrile humans, the environment, and animals; moreover, nine species and 29 serovars were recorded over the three Ecuadorian ecoregions. Leptospira infections were diagnosed in livestock, companion, and wild animals from the Amazon and the Coast regions along with sea lions from the Galápagos Islands. Microscopic-agglutination test was the diagnostic tool most widely used. Three reviews covering national data on outpatients and inpatients determined the varied annual incidence and mortality rate, with males being more commonly affected. No human cases have been reported in the Galápagos Islands. Genomic sequences of three pathogenic Leptospira were reported. No studies on clinical ground, antibiotic resistance, or treatment were reported, nor were control programs or clinical-practice guidelines found. The published literature demonstrated that leptospirosis was and still is an endemic disease with active transmission in the four geoclimatic regions of Ecuador including the Galápagos Islands. Animal infections, distributed in mainland and insular Ecuador, pose a significant health risk for humans. Nationwide epidemiological surveys—encouraging more research on the fauna and environment with appropriate sampling design on risk factors for human and animal leptospirosis, Leptospira genotyping, increased laboratory capability, and readily available official data—are required to improve our understanding of transmission patterns and to develop effective national intervention strategies with the intention of applying One Health approaches.

Leptospirosis is a zoonotic disease of worldwide distribution that affects humans, domestic and wild animals. This study evaluates the frequency of anti- Leptospira spp. antibodies in companion, livestock and wild mammals from a mixed use rescue center on Guayaquil, the main city of Ecuador. Sera were collected from 23 domestic and 6 wild mammals. All animals tested were seropositive for Leptospira spp. using Microscopic Agglutination Test (MAT), most of them for multiple serovars. Leptospira interrogans serovars Canicola, Hardjo and Icterohaemorrhagiae were the most frequent ones. We conclude that the presence of domestic animals at this mixed use rescue center may cause the exposure of wild animals, considering the high frequency of Leptospira spp. seropositivity already reported for livestock and companion animals in Ecuador. This is the first serological survey for leptospirosis including wild animals rescued from illegal traffic in Ecuador and point out the urgent need of exclusive rescue and conservation units for wild species and the potential role as Leptospira spp. reservoir for wild mammals.

Adrenocortical carcinoma (ACC) is a rare cancer in which tissue-specific differentiation is paradoxically associated with dismal outcomes. The differentiated ACC subtype CIMP-high is prevalent, incurable, and routinely fatal. CIMP-high ACC possess abnormal DNA methylation and frequent β-catenin-activating mutations. Here, we demonstrated that ACC differentiation is maintained by a balance between nuclear, tissue-specific β-catenin-containing complexes, and the epigenome. On chromatin, β-catenin bound master adrenal transcription factor SF1 and hijacked the adrenocortical super-enhancer landscape to maintain differentiation in CIMP-high ACC; off chromatin, β-catenin bound histone methyltransferase EZH2. SF1/β-catenin and EZH2/β-catenin complexes present in normal adrenals persisted through all phases of ACC evolution. Pharmacologic EZH2 inhibition in CIMP-high ACC expelled SF1/β-catenin from chromatin and favored EZH2/β-catenin assembly, erasing differentiation and restraining cancer growth in vitro and in vivo. These studies illustrate how tissue-specific programs shape oncogene selection, surreptitiously encoding targetable therapeutic vulnerabilities., Significance: Oncogenic β-catenin can use tissue-specific partners to regulate cellular differentiation programs that can be reversed by epigenetic therapies, identifying epigenetic control of differentiation as a viable target for β-catenin-driven cancers., (©2023 American Association for Cancer Research.)

Mitosis is the cellular process that ensures accurate segregation of the cell's genetic material into two daughter cells. Mitosis is often deregulated in cancer; thus drugs that target mitosis-specific proteins represent attractive targets for anticancer therapy. Numerous inhibitors have been developed against kinesin-5 Eg5, a kinesin essential for bipolar spindle assembly. Unfortunately, Eg5 inhibitors (K5Is) have been largely ineffective in the clinic, possibly due to the activity of a second kinesin, KIF15, that can suppress the cytotoxic effect of K5Is by driving spindle assembly through an Eg5-independent pathway. We hypothesized that pairing of K5Is with small molecule inhibitors of KIF15 will be more cytotoxic than either inhibitor alone. Here we present the results of a high-throughput screen from which we identified two inhibitors that inhibit the motor activity of KIF15 both in vitro and in cells. These inhibitors selectively inhibit KIF15 over other molecular motors and differentially affect the ability of KIF15 to bind microtubules. Finally, we find that chemical inhibition of KIF15 reduces the ability of cells to acquire resistance to K5Is, highlighting the centrality of KIF15 to K5I resistance and the value of these inhibitors as tools with which to study KIF15 in a physiological context.

The mitotic spindle, a self-constructed microtubule-based machine, segregates chromosomes during cell division. In mammalian cells, microtubule bundles called kinetochore fibers (k-fibers) connect chromosomes to the spindle poles. Chromosome segregation thus depends on the mechanical integrity of k-fibers. Here we investigate the physical and molecular basis of k-fiber bundle cohesion. We detach k-fibers from poles by laser ablation-based cutting, thus revealing the contribution of pole-localized forces to k-fiber cohesion. We then measure the physical response of the remaining kinetochore-bound segments of the k-fibers. We observe that microtubules within ablated k-fibers often splay apart from their minus-ends. Furthermore, we find that minus-end clustering forces induced by ablation seem at least partially responsible for k-fiber splaying. We also investigate the role of the k-fiber-binding kinesin-12 Kif15. We find that pharmacological inhibition of Kif15-microtubule binding reduces the mechanical integrity of k-fibers. In contrast, inhibition of its motor activity but not its microtubule binding ability, i.e., locking Kif15 into a rigor state, does not greatly affect splaying. Altogether, the data suggest that forces holding k-fibers together are of similar magnitude to other spindle forces, and that Kif15, acting as a microtubule cross-linker, helps fortify and repair k-fibers. This feature of Kif15 may help support robust k-fiber function and prevent chromosome segregation errors.

Kinesins are regulated in space and time to ensure activation only in the presence of cargo. Kinesin-binding protein (KIFBP), which is mutated in Goldberg-Shprintzen syndrome, binds to and inhibits the catalytic motor heads of 8 of 45 kinesin superfamily members, but the mechanism remains poorly defined. Here, we used cryo–electron microscopy and cross-linking mass spectrometry to determine high-resolution structures of KIFBP alone and in complex with two mitotic kinesins, revealing structural remodeling of kinesin by KIFBP. We find that KIFBP remodels kinesin motors and blocks microtubule binding (i) via allosteric changes to kinesin and (ii) by sterically blocking access to the microtubule. We identified two regions of KIFBP necessary for kinesin binding and cellular regulation during mitosis. Together, this work further elucidates the molecular mechanism of KIFBP-mediated kinesin inhibition and supports a model in which structural rearrangement of kinesin motor domains by KIFBP abrogates motor protein activity.

Ovarian cancer ranks fifth in cancer related deaths for women in USA. The high mortality rate associated with ovarian cancer is due to diagnosis at later stages of disease and the high recurrence rate of 60-80%. Recurrent ovarian cancers are more likely to present as multidrug resistance (MDR) leading to unfavorable response from 2 nd and 3 rd line chemotherapy. Nanoemulsions (NEs) are emerging as an attractive drug delivery system to overcome MDR challenges. NEs can also minimize exposure of therapeutic cargo to normal tissues potentially reducing side effects. In >80% of ovarian cancers, Folate Receptor-α (FR-α) is expressed at 10- to 100-fold higher levels than on non-pathological tissues. Therefore, folate (FA) is being evaluated as an active targeting moiety for FR-α + ovarian cancer. To improve therapeutic outcome with reduced toxicity, we developed NMI-500, a FA targeted gadolinium (Gd) annotated NE loaded with docetaxel (DTX). NMI-500 has been developed as theranostic agents as Gd will enable physician to acquire real time pharmacodynamics data on NE + DTX accumulation in target lesions. In present study, characterization for key translational metrics of NMI-500 showed size distribution in range of 120 to 150 nm and zeta potential around -45 mV. Active targeting of FA was evaluated against FR-α + KB cells and results demonstrated significant improvement in cell association which was surface ligand density dependent. We found that NMI-500 was able to inhibit tumor growth in a spontaneous transgenic ovarian cancer model with improved safety profile and this growth inhibition could be longitudinally followed by MRI. These results indicate NMI-500 warrants advancement to clinical trials.