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1.
J Helminthol ; 96: e64, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36017718

RESUMEN

Cosmocerca spp. are common nematode parasites of amphibians. We provide herein molecular data for two species of Cosmocerca and describe a new species, Cosmocerca albopunctata n. sp., using light microscopy and molecular data (cytochrome c oxidase subunit 1 - COI mtDNA). Cosmocerca albopunctata n. sp. can be easily distinguished from other congeneric species by the combination of characteristics such as body size, length of spicules and gubernaculum, and the arrangements and number of caudal papillae (7 + 1:1 + 1:6). The phylogenetic results based on the partial COI mtDNA sequences clustered the new species in a monophyletic clade along with the other sequences of Cosmocerca spp. Therefore, our results contribute to the knowledge about the species diversity and genetic data for Cosmocerca spp. in the Neotropical region.


Asunto(s)
Anuros , Ascarídidos , Animales , Anuros/parasitología , Brasil , ADN Mitocondrial/genética , Filogenia
2.
Lett Appl Microbiol ; 73(2): 139-148, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33843058

RESUMEN

Infections caused by KPC-producing Klebsiella pneumoniae (Kp-KPC) are associated with high mortality rates due to the increased number of resistant isolates and the scarcity of therapeutic options. This scenario reinforces the urgent need for new chemotherapeutics. Herein, we investigated the effects of 1,10-phenanthroline-5,6-dione (phendione) and its metal-based complexes, [Cu(phendione)3 ](ClO4 )2 .4H2 O (Cu-phendione) and [Ag(phendione)2 ]ClO4 (Ag-phendione), both alone and also combined with carbapenems (meropenem (MEM), and imipenem), against 46 clonally distinct clinical strains of Kp-KPC. All isolates were found to be multidrug resistant in accordance with their susceptibility patterns by disk diffusion method. Compounds geometric mean (GM)-MIC and GM-MBC values (µmol l-1 ), respectively, were: phendione, 42·06 and 71·27; Cu-phendione, 9·88 and 13·75; and Ag-phendione, 10·10 and 13·06. Higher synergism rates of MEM-containing combinations were observed by the checkerboard assay, particularly with the two metal complexes. Moreover, drug combinations were able to re-sensitize 87% of the phenotypically non-susceptible strains. Time-kill studies, with MEM plus Cu-phendione or Ag-phendione, indicated that combinations with 0·5× MIC of each agent produce synergistic effects after 9-12 h. The MEM plus Ag-phendione eradicated about 106  CFU per ml of bacteria. These findings support the effectiveness of the re-sensitizing combinatorial approach and provide evidence that phendione-based compounds offer real promise in the fight against Kp-KPC infections.


Asunto(s)
Carbapenémicos/farmacología , Complejos de Coordinación/farmacología , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Fenantrolinas/farmacología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/farmacología , Farmacorresistencia Bacteriana Múltiple , Sinergismo Farmacológico , Humanos , Imipenem/farmacología , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , beta-Lactamasas/farmacología
3.
Mol Cell Biochem ; 471(1-2): 63-69, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32472323

RESUMEN

Posterior tibial tendon (PTT) dysfunction is three times more common in females, and some patients may have a predisposition without a clinically evident cause, suggesting that individual characteristics play an important role in tendinopathy. The present study investigated the association of rs4986938 (+ 1730G > A; AluI RFLP) and rs1256049 (- 1082G > A; RsaI RFLP) single nucleotide polymorphisms (SNPs) of estrogen receptor-beta (ER-ß) gene with PTT dysfunction. A total of 400 participants were recruited. The PTT dysfunction group: these patients underwent surgery, with PTT tendinopathy confirmed by histopathology and magnetic resonance image (MRI). The control group was composed of participants with no clinical or MRI evidence of PTT dysfunction. Each group was composed of 100 postmenopausal women, 50 premenopausal women, and 50 men. Genomic DNA was extracted from saliva samples, and genotypes were obtained by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Concerning the ER-ß SNP rs4986938, there were significant differences in the frequencies of alleles between test and control groups of all the cases, only postmenopausal women and only men (p < 0.0001, p = 0.0016 and p = 0.0001). Considering the PTT dysfunction group and comparing postmenopausal women versus premenopausal women adding men, the analysis showed significant differences in the allelic distribution (p = 0.0450): the allele A in postmenopausal women is a risk factor. The ER-ß SNP rs1256049 did not show differences in the frequencies of alleles and genotypes between groups. The ER-ß SNP rs4986938, but not ER -ß SNPs rs1256049, may contribute to PTT insufficiency in the Brazilian population, with additional risk in postmenopausal women. Addition, in men the genetic factor could be more determinant.


Asunto(s)
Receptor beta de Estrógeno/genética , Disfunción del Tendón Tibial Posterior/genética , Tendinopatía/genética , Adulto , Alelos , Estudios de Casos y Controles , Estudios Transversales , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple , Disfunción del Tendón Tibial Posterior/patología , Posmenopausia , Tendinopatía/patología
4.
Lett Appl Microbiol ; 67(4): 392-399, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30019443

RESUMEN

Oropharyngeal candidiasis is the commonest mucocutaneous infection in HIV-positive individuals. Herein, samples were taken from oral cavities of 150 HIV-infected patients and cultured on Sabouraud-dextrose agar; 89 (59·3%) of 150 patients had positive culture for Candida and presented clinical sign of classical oral candidiasis. Totally, 102 morphologically distinct colonies were isolated from Candida positive cultures and subsequently identified by polymerase chain reaction and sequencing assay, presenting the following frequency: 54 C. albicans (52·9%), 16 C. dubliniensis (15·7%), 12 C. tropicalis (11·8%), 9 C. glabrata (8·8%), 7 C. kefyr (6·9%) and 4 C. africana (3·9%). Additionally, multiple Candida species were co-isolated from 13·5% (12/89) patients. Regarding the antifungal susceptibility test, which was performed by CLSI protocol (M27-A3/M27-S3), all Candida isolates were susceptible to amphotericin B and caspofungin, while some of them were resistant to fluconazole (17·6%; 16 C. albicans, 1 C. dubliniensis and 1 C. glabrata), itraconazole (16·7%; 15 C. albicans, 1 C. dubliniensis and 1 C. tropicalis) and voriconazole (5·9%; 5 C. albicans and 1 C. tropicalis). Collectively, our findings reinforce the urgent necessity to find new therapeutic agents to treat oral candidiasis in HIV-positive patients, especially due to the high incidence of azole-resistant Candida strains and the increased frequency of non-C. albicans species. SIGNIFICANCE AND IMPACT OF THE STUDY: The Candida species recovered from oral cavity of 150 Iranian HIV/AIDS patients and their antifungal susceptibility profiles were reported. Candida albicans was the commonest Candida species, followed by C. dubliniensis, C. tropicalis, C. glabrata, C. kefyr and C. africana. All Candida isolates were susceptible to amphotericin B and caspofungin, while resistance to azoles was detected. The growing drug-resistance profile reported in clinical isolates of C. albicans and non-C. albicans strains is a serious problem in hospitals worldwide. Consequently, the suitable antifungal choice to treat the HIV/AIDS population with oral candidiasis needs to be rethought and new therapeutic options must urgently arise.


Asunto(s)
Antifúngicos/uso terapéutico , Candida albicans , Candidiasis Bucal/tratamiento farmacológico , Candidiasis Bucal/epidemiología , Farmacorresistencia Fúngica Múltiple/genética , Infecciones por VIH/complicaciones , Boca/microbiología , Adolescente , Adulto , Anciano , Anfotericina B/uso terapéutico , Candida albicans/clasificación , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Candidiasis Bucal/microbiología , Caspofungina , Equinocandinas/uso terapéutico , Femenino , Fluconazol/uso terapéutico , Humanos , Incidencia , Irán/epidemiología , Itraconazol/uso terapéutico , Lipopéptidos/uso terapéutico , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Prevalencia , Adulto Joven
5.
6.
Bull Environ Contam Toxicol ; 100(2): 240-244, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29181607

RESUMEN

Cryptosporidium spp. has been recognized as an important pathogen. As bivalve mollusks are noted as potential sources of several pathogens due to their consumption as foodstuffs, the aim of this study was to investigate the occurrence of Cryptosporidium spp. oocysts in Perna perna mussels and in seawater samples from a mussel farm in Southeastern Brazil, where mussels are grown directly in the sea, attached to ropes. Oocysts were observed by microscopy and confirmed by an enzyme-linked immunosorbent assay. Oocysts were present in mussel gills and GI tracts, as well as in the seawater. Of the 100 females, 10% and 11% showed contaminated GI tracts and gills, respectively, while this rate was lower in males, at 5% and 8.9%. Oocysts were present in higher amounts in the GI tract compared to gills and water. Contamination of the study area is apparent, leading to public health risks. More in-depth studies are needed, including molecular investigations, to identify Cryptosporidium species in mussels, as well as the implementation of monitoring actions in animals destined for human consumption.


Asunto(s)
Cryptosporidium/fisiología , Exposición Dietética/estadística & datos numéricos , Monitoreo del Ambiente , Contaminación de Alimentos/estadística & datos numéricos , Perna/patogenicidad , Mariscos/estadística & datos numéricos , Animales , Brasil , Branquias , Humanos , Oocistos , Alimentos Marinos , Agua de Mar
8.
J Am Chem Soc ; 138(50): 16259-16265, 2016 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-27998088

RESUMEN

Aggregation and amyloid fibril formation of peptides and proteins is a widespread phenomenon. It has serious implications in a range of areas from biotechnological and pharmaceutical applications to medical disorders. The aim of this study was to develop a better understanding of the mechanism of aggregation and amyloid fibrillation of an important pharmaceutical, human glucagon-like peptide-1 (GLP-1). GLP-1 is a 31-residue hormone peptide that plays an important role regulating blood glucose levels, analogues of which are used for treatment of type 2 diabetes. Amyloid fibril formation of GLP-1 was monitored using thioflavin T fluorescence as a function of peptide concentration between pH 7.5 and 8.2. Results from these studies establish that there is a highly unusual pH-induced switch in GLP-1 aggregation kinetics. At pH 8.2, the kinetics are consistent with a nucleation-polymerization mechanism for fibril formation. However, at pH 7.5, highly unusual kinetics are observed, where the lag time increases with increasing peptide concentration. We attribute this result to the formation of off-pathway species together with an initial slow, unimolecular step where monomer converts to a different monomeric form that forms on-pathway oligomers and ultimately fibrils. Estimation of the pKa values of all the ionizable groups in GLP-1 suggest it is the protonation/deprotonation of the N-terminus that is responsible for the switch with pH. In addition, a range of biophysical techniques were used to characterize (1) the start point of the aggregation reaction and (2) the structure and stability of the fibrils formed. These results show that the off-pathway species form under conditions where GLP-1 is most prone to form oligomers.


Asunto(s)
Péptido 1 Similar al Glucagón/química , Agregado de Proteínas , Secuencia de Aminoácidos , Humanos , Concentración de Iones de Hidrógeno , Cinética , Multimerización de Proteína , Estructura Cuaternaria de Proteína
9.
Exp Parasitol ; 167: 67-75, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27223816

RESUMEN

The recognition of invading pathogens by the innate immune system is essential for host protection against human parasites and the initiation of an effective adaptive immune response. Innate immune cells such as macrophages and dendritic cells (DCs) are involved in the first line of defense against protozoan parasites via sensing the invaders through pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs). Activation of macrophages and dendritic cells starts with the interaction between microbial ligands (pathogen-associated molecular patterns - PAMPs) and PRRs, and these activated cells influence the overall immune response. Trypanosomatid PAMPs are sensed by TLRs; for example, TLR2 recognizes alkylacylglycerol and lipophosphoglycan in Trypanosoma cruzi and Leishmania, respectively; TLR2/TLR4 recognize glycoisnositolphospholipids and glycosylphosphatidyl inositol in Trypanosoma species; and TLR9 recognizes genomic DNA in Trypanosoma. TLR signaling includes the recruitment of different adaptor molecules that activate various transcription factors, such as NF-kB, IRF3/7, and MAP kinases, to induce the production of pro-inflammatory cytokines and type I interferons. Moreover, activated macrophages and dendritic cells produce ROS and NOS, which limit pathogen survival, and large amounts of cytokines; additionally, antigen presentation enhances the adaptive immune response. In this review, we highlight the recent findings on PAMP recognition in trypanosomatid infections and the signaling pathways activated by PRRs.


Asunto(s)
Inmunidad Innata , Leishmania/inmunología , Leishmaniasis/inmunología , Trypanosoma brucei brucei/inmunología , Trypanosoma cruzi/inmunología , Tripanosomiasis/inmunología , Animales , Células Dendríticas/inmunología , Humanos , Macrófagos/inmunología , Moléculas de Patrón Molecular Asociado a Patógenos/inmunología , Receptores Toll-Like/inmunología
10.
Biochim Biophys Acta ; 1830(8): 4265-73, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23643965

RESUMEN

BACKGROUND: Orthophosphate (Pi) is a central compound in the metabolism of all organisms, including parasites. There are no reports regarding the mechanisms of Pi acquisition by Trypanosoma cruzi. METHODS: (32)Pi influx was measured in T. cruzi epimastigotes. The expression of Pi transporter genes and the coupling of the uptake to Na(+), H(+) and K(+) fluxes were also investigated. The transport capacities of different evolutive forms were compared. RESULTS: Epimastigotes grew significantly more slowly in 2mM than in 50mM Pi. Influx of Pi into parasites grown under low Pi conditions took place in the absence and presence of Na(+). We found that the parasites express TcPho84, a H(+):Pi-symporter, and TcPho89, a Na(+):Pi-symporter. Both Pi influx mechanisms showed Michaelis-Menten kinetics, with a one-order of magnitude higher affinity for the Na(+)-dependent system. Collapsing the membrane potential with carbonylcyanide-p-trifluoromethoxyphenylhydrazone strongly impaired the influx of Pi. Valinomycin (K(+) ionophore) or SCH28028 (inhibitor of (H(+)+K(+))ATPase) significantly inhibited Pi uptake, indicating that an inwardly-directed H(+) gradient energizes uphill Pi entry and that K(+) recycling plays a key role in Pi influx. Furosemide, an inhibitor of the ouabain-insensitive Na(+)-ATPase, decreased only the Na(+)-dependent Pi uptake, indicating that this Na(+) pump generates the Na(+) gradient utilized by the symporter. Trypomastigote forms take up Pi inefficiently. CONCLUSIONS: Pi starvation stimulates membrane potential-sensitive Pi uptake through different pathways coupled to Na(+) or H(+)/K(+) fluxes. GENERAL SIGNIFICANCE: This study unravels the mechanisms of Pi acquisition by T. cruzi, a key process in epimastigote development and differentiation to trypomastigote forms.


Asunto(s)
Fosfatos/metabolismo , Potasio/metabolismo , Sodio/metabolismo , Trypanosoma cruzi/metabolismo , ATPasa Intercambiadora de Hidrógeno-Potásio/metabolismo , Concentración de Iones de Hidrógeno , Imidazoles/farmacología , Valinomicina/farmacología
11.
Spinal Cord ; 52(11): 817-20, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25112967

RESUMEN

BACKGROUND: Spinal cord injuries has increased together with urban violence and show a high rates of incidence. Besides the onus to patient and society, it can also cause other serious complications to victims. Acute pancreatitis has an important impact on this disease and has been underdiagnosed in several patients. OBJECTIVES: The aim of this study was investigate the association of acute pancreatitis in acute spinal cord injuries. The secondary aim was to propose an investigation protocol to early diagnose and prevent it. METHODS: A prospective observational study was conducted in 78 patients who presented acute spinal cord injury (SCI) at our emergency department, confirmed by clinical and imaging examination, in according to the American Spinal Injury Association (ASIA) Classification. Exclusion criteria were chronic or associate diseases in spinal cord, pancreatic direct trauma, alcoholism and chronic pancreatic disease. RESULTS: The association of acute pancreatitis in patients with SCI was 11.53%. The occurrence of pancreatitis or high levels of serum pancreatic enzymes in patients with ASIA A was 41.7% and only 4.17% in patients with ASIA E. In all, 55.2% of patients who presented pancreatitis or high levels of serum pancreatic enzymes had cervical level of SCI and 34.5% had thoracic level. Adynamic ileus was observed in 68.96% of this group. CONCLUSION: We concluded that, in acute spinal cord injuries, the occurrence of acute pancreatitis or high serum levels of pancreatic enzymes are more frequent in patients with ASIA A Classification, cervical/thoracic level of spinal injury and adynamic ileus.


Asunto(s)
Amilasas/sangre , Lipasa/sangre , Pancreatitis/sangre , Pancreatitis/etiología , Traumatismos de la Médula Espinal/complicaciones , Enfermedad Aguda , Adulto , Femenino , Enfermedades Gastrointestinales/etiología , Humanos , Masculino , Pancreatitis/diagnóstico , Pancreatitis/prevención & control , Estudios Prospectivos , Traumatismos de la Médula Espinal/clasificación
12.
Clin Psychol Psychother ; 21(1): 39-48, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-22962030

RESUMEN

AIMS: Major depression is more prevalent in patients with type 2 diabetes mellitus (T2DM) than in general population. Comparing psychotherapeutic and pharmacological treatment responses could help to inform the choice between available treatment options. METHOD: Thirty-four patients with T2DM and major depression detected by using the Hospital Anxiety-Depression Scale (HADS), the Montgomery-Äsberg Depression Rating Scale (MADRS) and a structured interview (Mini-International Neuropsychiatric Interview) were randomized to undergo Interpersonal Psychotherapy (IPT) or treatment with sertraline in a 3-month acute intervention course in addition to a 3-month continuation format. Provided that the initial MADRS score was not reduced ≥25% at week 6, these early non-responding patients continued treatment in a sequential add-on combined format. Psychological adjustment to diabetes, attachment style, diabetes self-efficacy, quality of life and HbA1c were also evaluated along intervention. RESULTS: Out of 22 early-responding patients (11 for each treatment type), 16 had clinically significant improvements (<50% initial MADRS score) at endpoint with 11 reaching remission (MADRS scores ≤8), and with no significant differences between IPT and sertraline. Within sequential add-on treatment, out of eight patients, only three of them achieved a clinically significant improvement and only one reached remission. CONCLUSIONS: These preliminary results suggested that IPT may be an option to treat major depression in T2DM against medical care with sertraline. Early non-responding patients likely need alternative or longer treatment interventions. Limitations of this study relate to small sample and absence of a control group, which was difficult to implement due to ethical restrictions. KEY PRACTITIONER MESSAGE: Findings suggest that Interpersonal Psychotherapy is a useful tool to treat major depression in type 2 diabetes patients. A significant number of type 2 diabetes patients with major depression do not achieve depression remission irrespective of the type of treatment. Further clinical research should focus on addictive effects of psychotherapy and psychopharmacology in the treatment of depressed patients with chronic somatic diseases.


Asunto(s)
Antidepresivos/uso terapéutico , Trastorno Depresivo Mayor/complicaciones , Trastorno Depresivo Mayor/terapia , Diabetes Mellitus Tipo 2/complicaciones , Psicoterapia/métodos , Sertralina/uso terapéutico , Análisis de Varianza , Trastorno Depresivo Mayor/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida/psicología , Resultado del Tratamiento
13.
Braz J Biol ; 84: e282989, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38922198

RESUMEN

Hepatozoon spp. are the most common haemoparasites reported from reptiles around the world, however, only six species have been described infecting crocodilians. In Brazil, Hepatozoon caimani Carini, 1909 is currently the only recognized species from the caiman hosts. This study provides new data on the diversity of species of Hepatozoon infecting Caiman crocodilus (Linnaeus) using molecular data and phylogenetic analysis, with additional support of morphological data of developmental stages from host blood and tissue. Forty-four individuals were collected and screened for haemogregarines, and blood and tissue samples were analysed by light microscopy with 31 (70.45%) infected. Hepatozoon spp. blood developmental stages included immature and mature gamonts with or without cytoplasmic vacuoles and free gamonts. Additionally, merogonic developmental stages were found in the liver and spleen of infected hosts. Based on the morphological and molecular data, this study identified two possible different species of Hepatozoon, being one of them the H. caimani with intragenotypic divergence.


Asunto(s)
Caimanes y Cocodrilos , Filogenia , Animales , Brasil , Caimanes y Cocodrilos/parasitología , Eucoccidiida/clasificación , Eucoccidiida/genética , Eucoccidiida/aislamiento & purificación , Coccidiosis/parasitología , Coccidiosis/veterinaria , Coccidios/clasificación , Coccidios/aislamiento & purificación , Coccidios/genética
14.
Theriogenology ; 215: 78-85, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38016304

RESUMEN

During in vitro maturation (IVM) cumulus-oocyte complexes (COCs) are exposed to conditions that can trigger oxidative stress, thus, reducing oocyte maturation and viability. Aiming to mitigate these detrimental conditions, the effects of IVM medium supplementation with anethole have been tested. Anethole, also known as trans-anethole (1-methoxy-4 [1-propenyl]-benzene), is a naturally occurring phenylpropanoid with various pharmacological properties, including antioxidant effects. However, no study has examined anethole effect on goat COCs during IVM. Thus, the aim of this study was to evaluate the effects of different anethole concentrations on oocyte maturation, oxidative stress, and in vitro development of caprine embryos after parthenogenetic activation. Goat COCs were selected and randomly distributed into the following treatments: TCM-199+ medium (control), or TCM-199+ medium supplemented with 30 µg/mL (AN30); 300 µg/mL (AN300) or 2000 µg/mL (AN2000) of anethole. After IVM, part of the COCs was chosen for oocyte viability and chromatin configuration, intracellular reactive oxygen species levels, and mitochondrial membrane potential assessment. Another part of COCs was parthenogenetically activated, and presumptive zygotes were cultured for 7 days. Results demonstrated that anethole at 30 µg/mL increased oocyte maturation and cleavage rates when compared to the other treatments (P < 0.05), as well as oocyte viability and in vitro embryo production when compared to the control treatment (P < 0.05). Additionally, treatment with anethole at 2000 µg/mL decreased oocyte nuclear maturation and cleavage rates when compared to other treatments (P < 0.05) and embryo production if compared to control and AN30 treatments (P < 0.05). Moreover, anethole at 2000 µg/mL increased mitochondrial membrane potential when compared to the other treatments (P < 0.05). In conclusion, anethole exerts a concentration-dependent effect during goat COCs IVM. For a more desirable outcome of oocyte viability and maturation, and in vitro embryo production, the use of anethole at 30 µg/mL is recommended.


Asunto(s)
Cabras , Técnicas de Maduración In Vitro de los Oocitos , Animales , Femenino , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Técnicas de Maduración In Vitro de los Oocitos/métodos , Cabras/fisiología , Oocitos/fisiología , Suplementos Dietéticos , Células del Cúmulo
15.
Biochim Biophys Acta ; 1820(7): 1001-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22456227

RESUMEN

BACKGROUND: Trypanosoma rangeli is dependent on the presence of exogenous orthophosphate (Pi) for maximal growth and ecto-phosphatase activity is responsible for Pi supply under low Pi. Here we investigated the mechanisms of Pi uptake. METHODS: We investigated the kinetics of 32Pi transport, its Na+ and H+ dependence, its correlation with the Na+-ATPase and H+-ATPase, and gene expression of the Na+:Pi cotransporter and Na+-ATPase. RESULTS: T. rangeli grown under limiting Pi transports this anion to the cytosol in the absence and presence of Na+, suggesting that influx is mediated by both Na+-independent and Na+-dependent transporters. Cloning studies demonstrated that this parasite expresses a Pi transporter not previously studied in trypanosomatids. The H+ ionophore, carbonylcyanide-p-trifluoromethoxyphenylhydrazone, decreased both components of 32Pi influx by 80-95%. The H+-ATPase inhibitor, bafilomycin A1, inhibited the Na+-independent mechanism. Furosemide, an inhibitor of ouabain-insensitive Na+-ATPase, decreased both uptake mechanisms of 32Pi to the same extent, whereas ouabain had no effect, indicating that the former is the pump responsible for inwardly directed Na+ and the electric gradients required by the transporters. Parasite growth in high Pi had a lower Pi influx than that found in those grown in low Pi, without alteration in TrPho89 expression, showing that turnover of the transporters is stimulated by Pi starvation. CONCLUSIONS: Two modes of Pi transport, one coupled to Na+-ATPase and other coupled to H+-ATPase seem to be responsible for Pi acquisition during development of T. rangeli. GENERAL SIGNIFICANCE: This study provides the first description of the mechanism of Pi transport across the plasma membrane of trypanosomatids.


Asunto(s)
Fosfatos/metabolismo , Rhodnius/parasitología , Sodio/metabolismo , Trypanosoma/metabolismo , Adenosina Trifosfatasas/antagonistas & inhibidores , Adenosina Trifosfatasas/metabolismo , Animales , Transporte Biológico , Proteínas de Transporte de Catión/antagonistas & inhibidores , Proteínas de Transporte de Catión/metabolismo , Membrana Celular/metabolismo , Inhibidores Enzimáticos/farmacología , Macrólidos/farmacología , Ouabaína/farmacología , ATPasas de Translocación de Protón/antagonistas & inhibidores , ATPasas de Translocación de Protón/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rhodnius/metabolismo , Trypanosoma/crecimiento & desarrollo
16.
Arch Orthop Trauma Surg ; 133(9): 1267-71, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23784318

RESUMEN

OBJECTIVE: The objectives of this present case study are to report a rare combination of a displaced talar neck fracture with a compression fracture of the calcaneocuboid joint in a 5-year-old child and to describe its radiological features, surgical treatment and clinical outcome. A 5-year-old male boy was injured in a car accident in which his left foot underwent one of the tires. On arrival at the hospital, a displaced talar neck fracture associated both with a cuboid fracture and compression of the articular surface of the cuboid at the calcaneocuboid join was identified. Fractures were fixed surgically. Leg was protected with a below-knee plaster split immobilization and non-weight-bearing for 5 weeks. After that period, the patient initiated a rehabilitation protocol with active and passive motion exercises. DISCUSSION: Fractures and fracture dislocations at the mid-tarsal joint have an important impact on the global foot function because malunion can result in post-traumatic arthritis and three-dimensional deformities of the foot. If a cuboid compression fracture is not reduced properly, it can result in the shortening of the lateral column with the development of an abduction, pronation and flat foot deformity. A talar neck fracture, if unreduced, can result in medial column displacement and rotational dislocation of the talar head, leading to a subluxation in the talonavicular joint with severe restriction of foot function. With early surgical treatment and open reduction and internal fixation, our patient recovered from the accident without having symptoms of pain, avascular necrosis, postoperative foot deformities or neurovascular deficits. CONCLUSIONS: The combination of a displaced talar neck fracture with a compression fracture of the calcaneocuboid joint in children usually requires correct diagnoses and early treatment with anatomic reduction and internal fixation to prevent severe post-traumatic deformities. LEVEL OF EVIDENCE: V.


Asunto(s)
Fracturas Óseas/complicaciones , Fracturas por Compresión/complicaciones , Traumatismo Múltiple , Astrágalo/lesiones , Articulaciones Tarsianas/lesiones , Preescolar , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Fracturas por Compresión/diagnóstico por imagen , Fracturas por Compresión/cirugía , Humanos , Masculino , Traumatismo Múltiple/diagnóstico por imagen , Traumatismo Múltiple/cirugía , Radiografía , Astrágalo/diagnóstico por imagen , Astrágalo/cirugía , Articulaciones Tarsianas/diagnóstico por imagen , Articulaciones Tarsianas/cirugía
17.
bioRxiv ; 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38014216

RESUMEN

Prolonged exposure to benzene, a prevalent volatile organic compound (VOC), at concentrations found in smoke, triggers hyperglycemia, and inflammation in mice. Corroborating this with existing epidemiological data, we show a strong correlation between environmental benzene exposure and metabolic impairments in humans. To uncover the underlying mechanisms, we employed a controlled exposure system and continuous glucose monitoring (CGM), revealing rapid blood glucose surges and disturbances in energy homeostasis in mice. These effects were attributed to alterations in the hypothalamic transcriptome, specifically impacting insulin and immune response genes, leading to hypothalamic insulin resistance and neuroinflammation. Moreover, benzene exposure activated microglial transcription characterized by heightened expression of IKKß/NF-κB-related genes. Remarkably, selective removal of IKKß in immune cells or adult microglia in mice alleviated benzene-induced hypothalamic gliosis, and protected against hyperglycemia. In summary, our study uncovers a crucial pathophysiological mechanism, establishing a clear link between airborne toxicant exposure and the onset of metabolic diseases.

18.
Braz J Biol ; 83: e275603, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37729317

RESUMEN

Foodborne diseases are common illnesses caused by the consumption of food contaminated with microorganisms, such as viruses, fungi, bacteria, and protozoa. Every year, 600 million people become ill and 420,000 people die as a result of consuming contaminated food. Therefore, food safety is an important issue. In this study, samples of homemade spiced mayonnaise and self-serve acai sold in the city of Araguaína, Tocantins, Brazil were analyzed for microbiological contaminants. Acai was collected from 10 stores, one sample from each store, and tested for mold, yeast, and coliforms, as well as coliform identification and total and thermotolerant coliform counts. Mayonnaise was collected from 20 snack bars, one sample from each. These samples were inoculated on MacConkey and Salmonella Shigella agar plates, and the plates were analyzed for growth. Salmonella spp. were detected in some Mayonnaise samples, and coliforms were detected in all acai samples; 60% of samples had thermotolerant coliforms, and only 40% were within the limits established by ANVISA. The collected samples of mayonnaise and acai were contaminated with molds and yeasts above the established limit of 103 CFU/g. Thus, the analyzed mayonnaise and acai samples were contaminated and unfit for consumption, demonstrating the importance of hygienic-sanitary measures in food handling.


Asunto(s)
Alimentos , Humanos , Brasil , Agar
19.
Earth Space Sci ; 9(3): e2021EA002119, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35865637

RESUMEN

This article is composed of three independent commentaries about the state of Integrated, Coordinated, Open, Networked (ICON) principles in the American Geophysical Union Biogeosciences section, and discussion on the opportunities and challenges of adopting them. Each commentary focuses on a different topic: (a) Global collaboration, technology transfer, and application (Section 2), (b) Community engagement, community science, education, and stakeholder involvement (Section 3), and (c) Field, experimental, remote sensing, and real-time data research and application (Section 4). We discuss needs and strategies for implementing ICON and outline short- and long-term goals. The inclusion of global data and international community engagement are key to tackling grand challenges in biogeosciences. Although recent technological advances and growing open-access information across the world have enabled global collaborations to some extent, several barriers, ranging from technical to organizational to cultural, have remained in advancing interoperability and tangible scientific progress in biogeosciences. Overcoming these hurdles is necessary to address pressing large-scale research questions and applications in the biogeosciences, where ICON principles are essential. Here, we list several opportunities for ICON, including coordinated experimentation and field observations across global sites, that are ripe for implementation in biogeosciences as a means to scientific advancements and social progress.

20.
Lett Appl Microbiol ; 52(4): 360-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21255057

RESUMEN

AIMS: To assess the variability in UV-B (280-320 nm) sensitivity of selected bacterial isolates from the surface microlayer and underlying water of the Ria de Aveiro (Portugal) estuary and their ability to recover from previous UV-induced stress. METHODS AND RESULTS: Bacterial suspensions were exposed to UV-B radiation (3·3 W m⁻²). Effects on culturability and activity were assessed from colony counts and (3) H-leucine incorporation rates, respectively. Among the tested isolates, wide variability in UV-B-induced inhibition of culturability (37·4-99·3%) and activity (36·0-98·0%) was observed. Incubation of UV-B-irradiated suspensions under reactivating regimes (UV-A, 3·65 W m⁻²; photosynthetic active radiation, 40 W m⁻²; dark) also revealed diversity in the extent of recovery from UV-B stress. Trends of enhanced resistance of culturability (up to 15·0%) and enhanced recovery in activity (up to 52·0%) were observed in bacterioneuston isolates. CONCLUSIONS: Bacterioneuston isolates were less sensitive and recovered more rapidly from UV-B stress than bacterioplankton isolates, showing enhanced reduction in their metabolism during the irradiation period and decreased culturability during the recovery process compared to bacterioplankton. SIGNIFICANCE AND IMPACT OF THE STUDY: UV exposure can affect the diversity and activity of microbial communities by selecting UV-resistant strains and alter their metabolic activity towards protective strategies.


Asunto(s)
Bacterias/efectos de la radiación , Plancton/efectos de la radiación , Rayos Ultravioleta , Microbiología del Agua , Bacterias/aislamiento & purificación , Plancton/aislamiento & purificación , Portugal , Agua de Mar/microbiología
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