RESUMEN
Malaria-causing parasites achieve rapid proliferation in human blood through multiple rounds of asynchronous nuclear division followed by daughter cell formation. Nuclear divisions critically depend on the centriolar plaque, which organizes intranuclear spindle microtubules. The centriolar plaque consists of an extranuclear compartment, which is connected via a nuclear pore-like structure to a chromatin-free intranuclear compartment. Composition and function of this non-canonical centrosome remain largely elusive. Centrins, which reside in the extranuclear part, are among the very few centrosomal proteins conserved in Plasmodium falciparum. Here we identify a novel centrin-interacting centriolar plaque protein. Conditional knock down of this Sfi1-like protein (PfSlp) caused a growth delay in blood stages, which correlated with a reduced number of daughter cells. Surprisingly, intranuclear tubulin abundance was significantly increased, which raises the hypothesis that the centriolar plaque might be implicated in regulating tubulin levels. Disruption of tubulin homeostasis caused excess microtubules and aberrant mitotic spindles. Time-lapse microscopy revealed that this prevented or delayed mitotic spindle extension but did not significantly interfere with DNA replication. Our study thereby identifies a novel extranuclear centriolar plaque factor and establishes a functional link to the intranuclear compartment of this divergent eukaryotic centrosome.
Asunto(s)
Microtúbulos , Proteínas Protozoarias , Tubulina (Proteína) , Centrosoma/metabolismo , Homeostasis , Microtúbulos/metabolismo , Tubulina (Proteína)/genética , Plasmodium falciparum , Proteínas Protozoarias/genéticaRESUMEN
Many of the currently available anti-parasitic and anti-fungal frontline drugs have severe limitations, including adverse side effects, complex administration, and increasing occurrence of resistance. The discovery and development of new therapeutic agents is a costly and lengthy process. Therefore, repurposing drugs with already established clinical application offers an attractive, fast-track approach for novel treatment options. In this study, we show that the anti-cancer drug candidate MitoTam, a mitochondria-targeted analog of tamoxifen, efficiently eliminates a wide range of evolutionarily distinct pathogens in vitro, including pathogenic fungi, Plasmodium falciparum, and several species of trypanosomatid parasites, causative agents of debilitating neglected tropical diseases. MitoTam treatment was also effective in vivo and significantly reduced parasitemia of two medically important parasites, Leishmania mexicana and Trypanosoma brucei, in their respective animal infection models. Functional analysis in the bloodstream form of T. brucei showed that MitoTam rapidly altered mitochondrial functions, particularly affecting cellular respiration, lowering ATP levels, and dissipating mitochondrial membrane potential. Our data suggest that the mode of action of MitoTam involves disruption of the inner mitochondrial membrane, leading to rapid organelle depolarization and cell death. Altogether, MitoTam is an excellent candidate drug against several important pathogens, for which there are no efficient therapies and for which drug development is not a priority.
Asunto(s)
Antineoplásicos , Trypanosoma brucei brucei , Animales , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Reposicionamiento de Medicamentos , Potencial de la Membrana Mitocondrial , Plasmodium falciparumRESUMEN
OBJECTIVE: Renal artery aneurysms are a rare condition; however, the rate of diagnosis has been increasing, because of the increasing use of complementary diagnostic methods. The best treatment strategy for RAAs remains controversial. Data on ex-vivo surgery associated with kidney autotransplantation are scarce. As a result, the goal of this study was to describe this technique and to report our results. METHODS: A retrospective monocentric study was undertaken using the clinical records and images of 35 patients diagnosed with renal artery aneurysm from 01/01/2010 to 31/12/2018. Indications for ex vivo surgery and autotransplantation were complex aneurysms with diameter >20 mm or rapid growth or symptomatic aneurysms or women wishing to become pregnant. Complex aneurysms were defined by anatomical criteria (bifurcation of the renal artery and its primary branches or hilar aneurysms) and/or physiological criteria (when time of warm ischemia in in-situ reconstruction is expected to last more than 45 minutes). The technique of ex-vivo surgery and autotransplantation consists of performing a nephrectomy, renal cooling, treatment of aneurysm in banking and implantation of the kidney in the homolateral iliac fossa. RESULTS: A total of 35 patients with 56 renal artery aneurysms (26 women, mean age 52.4 years-minimum and maximum 16 and 74 years) were included. Of these, 27 were treated by surgery and 8 were followed clinically. Among those treated surgically, 24 performed ex vivo surgery associated with autotransplantation. Regarding ex vivo surgery, nephrectomy was performed by laparoscopic surgery in 24 of the 27 surgeries, the mean surgical time was 5.3 hours, the median warm ischemia time was 4 minutes and the length of hospital stay was 12.2 days. Mortality was 0% and the kidney patency rate was 93% with a follow up of 47.2 months. Of the 17 patients with hypertension, 6 cured it, 4 improved and 7 maintained hypertension. CONCLUSION: Kidney autotransplantation appears to be efficient for most complex RAA with the possibility to minimize surgical aggression by performing laparoscopic nephrectomy.
Asunto(s)
Aneurisma/cirugía , Trasplante de Riñón , Laparoscopía , Nefrectomía , Arteria Renal/cirugía , Reimplantación , Adolescente , Adulto , Anciano , Aneurisma/diagnóstico por imagen , Femenino , Humanos , Trasplante de Riñón/efectos adversos , Laparoscopía/efectos adversos , Masculino , Persona de Mediana Edad , Nefrectomía/efectos adversos , Tempo Operativo , Complicaciones Posoperatorias/etiología , Reimplantación/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Trasplante Autólogo , Resultado del Tratamiento , Isquemia Tibia , Adulto JovenRESUMEN
The sporogonic stage of the life cycle of Plasmodium spp., the causative agents of malaria, occurs inside the parasite's mosquito vector, where a process of fertilization, meiosis, and mitotic divisions culminates in the generation of large numbers of mammalian-infective sporozoites. Efforts to cultivate Plasmodium mosquito stages in vitro have proved challenging and yielded only moderate success. Here, we describe a methodology that simplifies the in vitro screening of much-needed transmission-blocking (TB) compounds employing a bioluminescence-based method to monitor the in vitro development of sporogonic stages of the rodent malaria parasite Plasmodium berghei Our proof-of-principle assessment of the in vitro TB activity of several commonly used antimalarial compounds identified cycloheximide, thiostrepton, and atovaquone as the most active compounds against the parasite's sporogonic stages. The TB activity of these compounds was further confirmed by in vivo studies that validated our newly developed in vitro approach to TB compound screening.
Asunto(s)
Antimaláricos/farmacología , Malaria/transmisión , Plasmodium berghei/efectos de los fármacos , Animales , Anopheles/efectos de los fármacos , Antimaláricos/uso terapéutico , Drosophila , Proteínas de Drosophila/metabolismo , Insectos Vectores/efectos de los fármacos , Malaria/tratamiento farmacológico , Esporozoítos/efectos de los fármacosRESUMEN
Avermectins are powerful endectocides with an established potential to reduce the incidence of vector-borne diseases. Here, we show that several avermectins inhibit the hepatic stage of Plasmodium infection in vitro Notably, ivermectin potently inhibits liver infection in vivo by impairing parasite development inside hepatocytes. This impairment has a clear impact on the ensuing blood stage parasitemia, reducing disease severity and enhancing host survival. Ivermectin has been proposed as a tool to control malaria transmission because of its effects on the mosquito vector. Our study extends the effect of ivermectin to the early stages of mammalian host infection and supports the inclusion of this multipurpose drug in malaria control strategies.
Asunto(s)
Ivermectina/análogos & derivados , Ivermectina/uso terapéutico , Hígado/parasitología , Malaria/tratamiento farmacológico , Plasmodium/efectos de los fármacos , Plasmodium/patogenicidad , Animales , Línea Celular Tumoral , Culicidae , HumanosRESUMEN
A structure-activity relationship study was performed with ten 8-aminoquinoline-squaramides compounds active against liver stage malaria parasites, using human hepatoma cells (Huh7) infected by Plasmodium berghei parasites. In addition, their blood-schizontocidal activity was assessed against chloroquine-resistant W2 strain Plasmodium falciparum. Compound 3 was 7.3-fold more potent than the positive control primaquine against liver-stage parasites, illustrating the importance of the squarate moiety to activity.
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Antiprotozoarios/farmacología , Hígado/parasitología , Malaria/parasitología , Plasmodium falciparum/efectos de los fármacos , Quinina/análogos & derivados , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Malaria/tratamiento farmacológico , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Quinina/síntesis química , Quinina/química , Quinina/farmacología , Relación Estructura-ActividadRESUMEN
We report the pharmacological activity of organoruthenium complexes containing chloroquine (CQ) as a chelating ligand. The complexes displayed intraerythrocytic activity against CQ-sensitive 3D7 and CQ-resistant W2 strains of Plasmodium falciparum, with potency and selectivity indexes similar to those of CQ. Complexes displayed activity against all intraerythrocytic stages, but moderate activity against Plasmodium berghei liver stages. However, unlike CQ, organoruthenium complexes impaired gametocyte viability and exhibited fast parasiticidal activity against trophozoites for P. falciparum. This functional property results from the ability of complexes to quickly induce oxidative stress. The parasitaemia of P. berghei-infected mice was reduced by treatment with the complex. Our findings demonstrated that using chloroquine for the synthesis of organoruthenium complexes retains potency and selectivity while leading to an increase in the spectrum of action and parasite killing rate relative to CQ.
Asunto(s)
Antimaláricos/farmacología , Cloroquina/farmacología , Compuestos Organometálicos/farmacología , Plasmodium berghei/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Rutenio/farmacología , Animales , Antimaláricos/administración & dosificación , Cloroquina/administración & dosificación , Modelos Animales de Enfermedad , Malaria/tratamiento farmacológico , Ratones , Compuestos Organometálicos/administración & dosificación , Estrés Oxidativo , Parasitemia/tratamiento farmacológico , Rutenio/administración & dosificación , Resultado del TratamientoRESUMEN
BACKGROUND: Drug resistance in Plasmodium falciparum has posed an obstacle to effective treatment and challenges many malaria control programmes in endemic areas. In Angola, until 2003, chloroquine (CQ) was used as first-line therapy for uncomplicated malaria. It was replaced initially by amodiaquine and, in 2006, by artemisinin-based combination therapy (ACT) with artemether-lumefantrine (AL, Coartem(®)). Efficacy study of ACT, conducted in Angola between 2004 and 2005, showed a baseline efficacy of ≈99%. METHODS: 103 malaria patients were enrolled according to WHO proceedings. Patients were followed up with clinical and parasitological evaluations for 28 days, parasite density and identification was evaluated by microscopy, the pfmsp2 were genotyped by nested-PCR, to distinguish parasite recrudescence from new infections; the polymorphisms at codons 86 and 1246 of pfmdr1 gene, and 769 of pfatp6 gene were assessed by PCR-RFLP and sequencing for pfk13-propeller genotype. RESULTS: The cure rate was 91.3%. The obtained results showed that from 103 patients, 12.6% (n = 13) still had parasitaemia 1 day after the treatment was finished. On day 0, of the 94 evaluated samples, wild-type alleles were identified in 73.4% (n = 69) for pfmdr1 N86Y position and only one sample carried the mutant allele (Y) for pfmdr1 1246; 14% of these samples showed increased pfmdr1 copy number; 100% (n = 21) had wild-type allele of k13 gene in all the studied positions. DISCUSSION: These results showed changes in parasite profile susceptibility to AL in comparison to the baseline data from 2002 to 2004 and on the genotyping characteristics; the clinical outcome after treatment with AL did not link a particular genotype with treatment failure; observed changes do not provide sufficient evidence for a treatment policy change, but they suggest that a carefully monitoring is needed in this area.
Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , ATPasas Transportadoras de Calcio/genética , Etanolaminas/uso terapéutico , Fluorenos/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Plasmodium falciparum/genética , Polimorfismo Genético , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angola , Combinación Arteméter y Lumefantrina , Niño , Preescolar , Combinación de Medicamentos , Resistencia a Medicamentos , Femenino , Técnicas de Genotipaje , Humanos , Lactante , Malaria Falciparum/parasitología , Masculino , Persona de Mediana Edad , Plasmodium falciparum/efectos de los fármacos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Estudios Prospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: The prevalence of allergic diseases such as asthma has significantly increased worldwide, making it a public health concern. There is an urgent need for new anti-inflammatory agents with selective pharmacology and lower toxicity. Plant extracts have been used for centuries in traditional medicine to alleviate inflammatory diseases. In this work, we evaluated the anti-allergic activity of Cymbopogon citratus (Cy), a medicinal herb used by folk medicine to treat asthma. METHODS: We used a murine model of respiratory allergy to the mite Blomia tropicalis (Bt) and evaluated certain parameters known to be altered in this model. A/J mice were sensitized (100 µg/animal s.c.) and challenged (10 µg/animal i.n.) with Bt mite extract and treated with 60, 120 or 180 mg/kg of Cy standardized hexane extract. The parameters evaluated included: cellular infiltrate in bronchoalveolar lavage (BAL); eosinophil peroxidase activity (EPO); histopathological examination of the lung; serum levels of specific IgE, IgG1 and IgG2a; Th2 cytokine concentrations in BAL and expression of NF-κB. RESULTS: Our results showed that oral administration of a Cy hexane extract (especially 180 mg/Kg) reduced the numbers of leukocytes/eosinophils in BAL; the eosinophil peroxidase activity in BAL; the infiltration of leukocytes in lung tissue; the production of mucus in the respiratory tract; the level of IL-4 in BAL and the nuclear expression of NF-κB. CONCLUSIONS: The results presented demonstrate the potential of the Cy hexane extract to modulate allergic asthma; this extract may be an alternative future approach to treat this pathology.
Asunto(s)
Antialérgicos/uso terapéutico , Antiinflamatorios/uso terapéutico , Cymbopogon , Hipersensibilidad/tratamiento farmacológico , Pulmón/efectos de los fármacos , FN-kappa B/metabolismo , Fitoterapia , Alérgenos/inmunología , Animales , Antialérgicos/farmacología , Antiinflamatorios/farmacología , Asma/tratamiento farmacológico , Asma/metabolismo , Líquido del Lavado Bronquioalveolar/inmunología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Peroxidasa del Eosinófilo/metabolismo , Eosinófilos/metabolismo , Hipersensibilidad/metabolismo , Interleucina-4/inmunología , Leucocitos/metabolismo , Pulmón/metabolismo , Masculino , Ratones , Ácaros , Moco/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Transducción de Señal/efectos de los fármacosRESUMEN
BACKGROUND: Anti-malarial resistance in Plasmodium falciparum remains an obstacle for malaria control. Resistance-associated genes were analysed in Brazilian samples over four decades to evaluate the impact of different treatment regimens on the parasite genetic profile. METHODS: Samples were collected on filter paper from patients infected in the Amazon region from 1984 to 2011. DNA was extracted with Chelex® 100 and monoinfection confirmed by PCR. SNPs in the pfcrt, pfmdr1, pfdhfr and pfdhps genes were assessed by PCR-RFLP. The pfmdr1 copy number was estimated using real time quantitative PCR with SYBR® Green. Parasite response was assessed ex vivo with seven concentrations of each anti-malarial. Patients were treated according to Brazilian guidelines: quinine plus tetracycline or mefloquine in period 1 and ACT in period 2. RESULTS: All 96 samples presented the pfcrt 76T mutant throughout the assessed periods. In addition, all isolates showed ex vivo chloroquine resistance. The pfmdr1 86Y was detected in 1.5% of samples in period 1, and in 25% in period 2. All samples presented the pfmdr1 1246Y. The analysis of pfmdr1 copy number showed amplification in 37.3% in period 1 and in 42% in period 2. Mutations in pfdhfr were shown as follows: 51I in all samples in period 1 and in 81.2% in period 2; 59R in 6.4% in period 2. The pfdhfr 108N and the pfdhps 437G were seen in all samples along time; the pfdhps 540E in 93.7% in period 1 and in 75% in period 2. CONCLUSIONS: The 76T mutation associated to chloroquine resistance is still present in the parasite population, although this anti-malarial was withdrawn from the chemotherapy of P. falciparum in Brazil in the mid-1980s. All isolates assayed ex vivo for chloroquine showed resistant phenotype and 76T. No association was observed between pfmdr1 mutations and resistance to quinine, mefloquine and artemisinin derivatives. Additionally, the pfdhfr 108N mutation was detected in all samples throughout the evaluated periods, demonstrating fixation of the mutant allele in the parasite population. Changes in Brazilian national guidelines for the malaria chemotherapy in the last 27 years yielded a discreet genetic impact in the parasite population.
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Antimaláricos/farmacología , Malaria Falciparum/parasitología , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Brasil , Resistencia a Medicamentos/genética , Marcadores Genéticos/genética , Genotipo , Humanos , Malaria Falciparum/tratamiento farmacológico , Polimorfismo de Nucleótido SimpleRESUMEN
PURPOSE: There are multiple postexercise recovery technologies available in the market based on the assumption of blood-flow enhancement. Lower-limb intermittent pneumatic compression (IPC) has been widely used, but the available scientific evidence supporting its effectiveness remains scarce, requiring a deeper investigation into its underlying mechanisms. The aim of this study was to assess the hemodynamic effects caused by the use of IPC at rest. METHODS: Twenty-two soccer and track and field athletes underwent two 15-minute IPC protocols (moderate- [80 mm Hg] and high-pressure [200 mm Hg]) in a randomized order. Systolic peak velocity, end-diastolic peak velocity, arterial diameter, and heart rate were measured before, during (at the eighth minute), and 2 minutes after each IPC protocol. RESULTS: Significant effects were observed between before and during (eighth minute) the IPC protocol for measures of systolic (P < .001) and end-diastolic peak velocities (P < .001), with the greater effects observed during the high-pressure protocol. Moreover, 2 minutes after each IPC protocol, hemodynamic variables returned to values close to baseline. Arterial diameter presented significant differences between pressures during the IPC protocols (P < .05), while heart rate remained unaltered. CONCLUSION: IPC effectively enhances transitory blood flow of athletes, particularly when applying high-pressure protocols.
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Estudios Cruzados , Frecuencia Cardíaca , Hemodinámica , Aparatos de Compresión Neumática Intermitente , Fútbol , Humanos , Fútbol/fisiología , Frecuencia Cardíaca/fisiología , Masculino , Hemodinámica/fisiología , Adulto Joven , Método Doble Ciego , Atletismo/fisiología , Adulto , Velocidad del Flujo Sanguíneo/fisiología , Atletas , Flujo Sanguíneo Regional , Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/fisiologíaRESUMEN
INTRODUCTION: Blunt thoracic aortic injuries (BTAI) once had mortality rates up to 32%, but the advent of thoracic endovascular aortic repair (TEVAR) has significantly improved outcomes. However, concerns persist regarding long-term devicerelated complications, device integrity in aging aortas, and the criteria for selecting patients for endovascular repair. We aimed to assess BTAI treatment strategies based on injury grade and their associated outcomes. METHODS: A systematic search of MedLine and Scopus databases was conducted to identify original articles published after 2013, which provided information on injury characteristics, outcomes, secondary effects, and reinterventions following BTAI. We classified aortic injuries following the SVS Clinical Practice Guidelines. RESULTS: We included 28 studies involving 1888 BTAI patients, including 5 prospective studies. Most patients were under 45 years old (86.4%), and grade III injuries were the most common (901 patients), followed by grades I and II (307 and 291 patients, respectively). TEVAR was performed in 1458 patients, mainly with grade III and IV injuries (1040 patients). Approximately half of the grade I injuries (153 of 307) were treated with TEVAR. Thirty-day mortality rate was 11.2%, primarily due to associated injuries. Aortic-related deaths were reported in 21 studies, with an overall rate of 2.2%, but none occurred beyond the first 30 days. Partial or complete coverage of the left subclavian artery was performed in 522 patients, with 27.9% requiring immediate or delayed revascularization. Aortic reintervention rates were relatively low (3.9%). CONCLUSION: TEVAR effectively treats BTAI grades III and IV, with potential benefit for some grade II injuries with more aggressive early intervention. Despite SVS guidelines suggesting conservative management for grade I injuries, there is a substantial rate of intervention with positive outcomes and low mortality. Long-term follow-up data, extending up to almost 20 years, reveal the durability of grafts, aortic remodeling, and minimal reintervention and complications.
Asunto(s)
Aorta Torácica , Procedimientos Endovasculares , Lesiones del Sistema Vascular , Heridas no Penetrantes , Humanos , Heridas no Penetrantes/cirugía , Heridas no Penetrantes/mortalidad , Heridas no Penetrantes/terapia , Aorta Torácica/lesiones , Aorta Torácica/cirugía , Procedimientos Endovasculares/métodos , Lesiones del Sistema Vascular/cirugía , Lesiones del Sistema Vascular/mortalidad , Resultado del Tratamiento , Adulto , Traumatismos Torácicos/cirugía , Traumatismos Torácicos/mortalidad , Traumatismos Torácicos/terapiaRESUMEN
OBJECTIVE: To describe independent factors related to the interaction of FTO rs9939609, TMEM18 rs6548238, leptin, and adiponectin in children/adolescents with asthma, under the influence of obesity. METHODS: The authors performed a cross-sectional study with 57 children/adolescents, ages 8-19 years, at a tertiary hospital, from 2017 to 2018. Participants were classified by nutritional status, performed spirometry with a bronchodilator test and completed an asthma questionnaire, higher scores indicated more asthma symptoms. Two asthma groups were formed: Group 1(G1)-normal-weight; Group 2(G2)-overweight/obese. Serum was collected for adipokines (n = 32) and genetic polymorphisms (n = 53) dosages. RESULTS: Age and body mass index (BMI) correlated directly in normal-weight (p = 0.009) and obese participants (p = 0.004). Girls reported more asthma complaints (p = 0.044). Participants with negative bronchodilator responses presented lower BMI (14.55-17.16) than responders (19.4-26.84) (p = 0.049). Leptin dosages are related directly to BMI (5,34-40 ng/ml in obese × 0,54-42 ng/ml in nonobese) (p = 0.003). Levels were high in girls (4.78-17.55 µg/ml) (p = 0.029) and low in nonobese boys (0.54-6.92 µg/ml) (p = 0.006). In obese, low leptin levels (< 10 ng/ml) were found in small airway dysfunction carriers (p = 0.025); elevated adiponectin (> 5 µg/ml) correlated with FEV1/FVC > 80 % (p = 0.035) and positive bronchodilator tests (8.84-13 µg/ml) (p = 0.039); and FTO A allele correlated with low adiponectin 0-8.84 µg/ml (p = 0.021) and low FEV1/FVC (46 %-88 %) (p = 0.023). CONCLUSION: BMI correlated directly with age and leptin levels. Obese participants presented high serum levels of leptin and FTO A allele correlated with low FEV1/FVC. Larger cohorts are necessary for better elucidation of the role of adipokines and polymorphisms in the pathophysiology of asthma and obesity.
RESUMEN
Iron, as an essential micronutrient, plays a crucial role in host-pathogen interactions. In order to limit the growth of the pathogen, a common strategy of innate immunity includes withdrawing available iron to interfere with the cellular processes of the microorganism. Against that, unicellular parasites have developed powerful strategies to scavenge iron, despite the effort of the host. Iron-sequestering compounds, such as the approved and potent chelator deferoxamine (DFO), are considered a viable option for therapeutic intervention. Since iron is heavily utilized in the mitochondrion, targeting iron chelators in this organelle could constitute an effective therapeutic strategy. This work presents mitochondrially targeted DFO, mitoDFO, as a candidate against a range of unicellular parasites with promising in vitro efficiency. Intracellular Leishmania infection can be cleared by this compound, and experimentation with Trypanosoma brucei 427 elucidates its possible mode of action. The compound not only affects iron homeostasis but also alters the physiochemical properties of the inner mitochondrial membrane, resulting in a loss of function. Furthermore, investigating the virulence factors of pathogenic yeasts confirms that mitoDFO is a viable candidate for therapeutic intervention against a wide spectrum of microbe-associated diseases.
Asunto(s)
Antiinfecciosos , Hierro , Deferoxamina/química , Antiparasitarios/farmacología , Quelantes del Hierro/farmacología , Quelantes del Hierro/uso terapéutico , MitocondriasRESUMEN
Plasmodium falciparum proliferates through schizogony in the clinically relevant blood stage of infection. During schizogony, consecutive rounds of DNA replication and nuclear division give rise to multinucleated stages before cellularization occurs. Although these nuclei reside in a shared cytoplasm, DNA replication and nuclear division occur asynchronously. Here, by mapping the proteomic context of the S-phase-promoting kinase PfCRK4, we show that it has a dual role for nuclear-cycle progression: PfCRK4 orchestrates not only DNA replication, but in parallel also the rearrangement of intranuclear microtubules from hemispindles into early mitotic spindles. Live-cell imaging of a reporter parasite showed that these microtubule rearrangements coincide with the onset of DNA replication. Together, our data render PfCRK4 a key factor for nuclear-cycle progression, linking entry into S-phase with the initiation of mitotic events. In part, such links may compensate for the absence of canonical cell cycle checkpoints in P. falciparum. IMPORTANCE The human malaria parasite Plasmodium falciparum proliferates in erythrocytes through schizogony, forming multinucleated stages before cellularization occurs. In marked contrast to the pattern of proliferation seen in most model organisms, P. falciparum nuclei multiply asynchronously despite residing in a shared cytoplasm. This divergent mode of replication is, thus, a good target for therapeutic interventions. To exploit this potential, we investigated a key regulator of the parasite's unusual cell cycle, the kinase PfCRK4 and found that this kinase regulated not only DNA replication but also in parallel the rearrangement of nuclear microtubules into early mitotic spindles. Since canonical cell cycle checkpoints have not been described in P. falciparum parasites, linking entry into S-phase and the initiation of mitotic events via a kinase, may be an alternative means to exert control, which is typically achieved by checkpoints.
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Malaria Falciparum , Plasmodium falciparum , Humanos , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Proteómica , División Celular , Ciclo Celular , Fase S , Malaria Falciparum/parasitología , Eritrocitos/parasitología , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismoRESUMEN
Paraneoplastic pruritus has been reported mostly in association with haematological malignancies, and rarely with solid tumours. Aquagenic pruritus is itching without any skin lesion that develops a few minutes after contact with water of any temperature and it is associated with polycythaemia vera or other lymphoproliferative diseases. Here we report a case of a previously healthy 78-year-old Portuguese woman, who had been treated unsuccessfully for aquagenic pruritus for the previous eight months, and presented to the emergency department complaining of pain and swelling in her left leg. Deep vein thrombosis was diagnosed and oral anticoagulation was initiated. Blood tests revealed a normal blood count and normal liver enzymes, except for alkaline phosphatase and lactate dehydrogenase levels, which were slightly elevated. Hypercobalaminaemia and folic acid deficiency were also noted. JAK2 V617F/12 exon mutation was not present. Thoracic, abdominal and pelvic computed tomography revealed a locally advanced pancreatic tumour. Ultrasound-guided fine-needle aspiration cytology of the lesion revealed a moderately differentiated adenocarcinoma of pancreatic ductal origin. Tumour marker assays showed elevation of both carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA 19-9). Aquagenic pruritus should be thoroughly investigated to exclude a neoplastic disease, especially if treatment is refractory or if another paraneoplastic syndrome is present. Although aquagenic pruritus is more commonly associated with haematological malignancies than solid tumours, a rare case of aquagenic pruritus is described here as a paraneoplastic syndrome of pancreatic cancer. To the best of our knowledge, this is the first case of pancreatic cancer that presented with aquagenic pruritus and dual paraneoplastic syndromes.
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BACKGROUND: Associated with considerable risk of morbidity, Total Pelvic Exenteration (TPE) is a life-altering procedure involving a significant prolonged recovery. As a result, and with the view of achieving the best outcomes and lessen short and long-term morbidities, a well-thought-out and coordinated multidisciplinary team approach, is crucial to the provision of safe and high-quality care. METHOD: Using a nominal group technique and qualitative methodology, this article explores the current practices in the care of oncology patients who undergo TPE surgery, in a tertiary cancer centre, by highlighting considerations of a collaboratively multi-disciplinary team. RESULTS: This article provides guidance on the multi-disciplinary team approach, relating to TPE surgery, with discussion of clinical concerns, and with the goal of high patient satisfaction, provision of effective care and the lessening of short and long-term morbidities. CONCLUSION: Oncology patients that undergo TPE surgery benefit from the contribution of a diversified multidisciplinary team as skilled and competent care that meets patient's health and social care needs is provided in a holistic, comprehensive, and timely care manner. Improving patient's care, pathway and postoperative outcomes, with the use of clinical expertise and support from professionals in the multidisciplinary team, can maximise care.
Asunto(s)
Neoplasias Colorrectales , Exenteración Pélvica , Neoplasias del Recto , Humanos , Exenteración Pélvica/métodos , Neoplasias Colorrectales/cirugía , Morbilidad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/cirugía , Recurrencia Local de Neoplasia/cirugía , Atención a la Salud , Neoplasias del Recto/cirugíaRESUMEN
Background: Inflammatory bowel diseases (IBDs) are chronic conditions that negatively interferes with the quality of life of the patients, on a physical, emotional, and social level. Its symptoms can vary including diarrhea, bleeding, abdominal pain, fever, and weight loss, depending on the type and location and severity of the disease. Despite evolving treatment, they do not always achieve control of the symptoms, so between 23% and 45% of people with idiopathic chronic ulcerative colitis, and up to 75% of those with Crohn's disease, eventually, will need surgery. Objective: The increase in its incidence in Latin America has promoted a renewed interest on the part of the medical and scientific community in standardizing and unifying criteria for the proper diagnosis and management of the disease, which is part of the current discussions of various events; however, this interest has not yet been reflected in policies and initiatives by governments to address the disease. We decided to develop a consensus meeting in order to elucidate the actual situation of IBD care in our region. Design: The methodology employed to build the consensus document derived from a review of literature, evidence, and policies on IBD, followed by a process of validation and feedback with a group of 10 experts in the field. Methods: Nine experts from different countries in Latin America were reunited in web meetings on 2 days and voted on topics derived from the consensus document. A full agreement with 100% approval was needed, so topics were discussed to reach the consensus otherwise were removed. Results: There is still a lack of information about IBD in Latin America, therefore IBD continues to be an 'invisible' disease and is little recognized by decision-makers. Conclusion: This document describes the current situation of IBDs in the Latin American region, highlighting the main barriers and challenges in timely access to diagnosis and treatment, in order to demonstrate the need to promote the development and implementation of policies, in order to improve the quality of care of patients with IBD.