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1.
Antonie Van Leeuwenhoek ; 117(1): 78, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38740670

ABSTRACT

Staphylococcus aureus is the etiologic agent of many nosocomial infections, and its biofilm is frequently isolated from medical devices. Moreover, the dissemination of multidrug-resistant (MDR) strains from this pathogen, such as methicillin-resistant S. aureus (MRSA) strains, is a worldwide public health issue. The inhibition of biofilm formation can be used as a strategy to weaken bacterial resistance. Taking that into account, we analysed the ability of marine sponge-associated bacteria to produce antibiofilm molecules, and we found that marine Priestia sp., isolated from marine sponge Scopalina sp. collected on the Brazilian coast, secretes proteins that impair biofilm development from S. aureus. Partially purified proteins (PPP) secreted after 24 hours of bacterial growth promoted a 92% biofilm mass reduction and 4.0 µg/dL was the minimum concentration to significantly inhibit biofilm formation. This reduction was visually confirmed by light microscopy and Scanning Electron Microscopy (SEM). Furthermore, biochemical assays showed that the antibiofilm activity of PPP was reduced by ethylenediaminetetraacetic acid (EDTA) and 1,10 phenanthroline (PHEN), while it was stimulated by zinc ions, suggesting an active metallopeptidase in PPP. This result agrees with mass spectrometry (MS) identification, which indicated the presence of a metallopeptidase from the M28 family. Additionally, whole-genome sequencing analysis of Priestia sp. shows that gene ywad, a metallopeptidase-encoding gene, was present. Therefore, the results presented herein indicate that PPP secreted by the marine Priestia sp. can be explored as a potential antibiofilm agent and help to treat chronic infections.


Subject(s)
Anti-Bacterial Agents , Bacterial Proteins , Biofilms , Staphylococcus aureus , Biofilms/drug effects , Biofilms/growth & development , Staphylococcus aureus/drug effects , Staphylococcus aureus/physiology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Anti-Bacterial Agents/pharmacology , Animals , Microbial Sensitivity Tests , Brazil , Porifera/microbiology
2.
J Basic Microbiol ; 64(2): e2300444, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38051942

ABSTRACT

The aim of this study was to investigate the production, stability and applicability of colorants produced by filamentous fungi isolated from soil samples from the Amazon. Initially, the isolates were evaluated in a screening for the production of colorants. The influences of cultivation and nutritional conditions on the production of colorants by fungal isolates were investigated. The colorants produced by selected fungal isolates were chemically characterized using the Liquid Chromatography-Mass Spectrometry technique. The antimicrobial and cytotoxic activities, stability evaluation and applicability of the colorants were investigated. As results, we observed that the isolates Penicillium sclerotiorum P3SO224, Clonostachys rosea P2SO329 and Penicillium gravinicasei P3SO332 stood out since they produced the most intense colorants. Compounds produced by Penicillium sclerotiorum P3SO224 and Clonostachys rosea P2SO329 were identified as sclerotiorin and penicillic acid. The colorant fraction (EtOAc) produced by these species has antimicrobial activity, stability at temperature and at different pHs, stability when exposure to light and UV, and when exposed to different concentrations of salts, as well as being nontoxic and having the ability to dye fabrics and be used as a pigment in creams and soap. Considering the results found in this study, it was concluded that fungi from the soil in the Amazon have the potential to produce colorants with applications in the textile and pharmaceutical industries.


Subject(s)
Anti-Infective Agents , Hypocreales , Penicillium , Pigments, Biological/chemistry , Fungi/chemistry , Soil
3.
Glia ; 71(8): 1791-1803, 2023 08.
Article in English | MEDLINE | ID: mdl-36866453

ABSTRACT

Zika virus (ZIKV) is a strongly neurotropic flavivirus whose infection has been associated with microcephaly in neonates. However, clinical and experimental evidence indicate that ZIKV also affects the adult nervous system. In this regard, in vitro and in vivo studies have shown the ability of ZIKV to infect glial cells. In the central nervous system (CNS), glial cells are represented by astrocytes, microglia, and oligodendrocytes. In contrast, the peripheral nervous system (PNS) constitutes a highly heterogeneous group of cells (Schwann cells, satellite glial cells, and enteric glial cells) spread through the body. These cells are critical in both physiological and pathological conditions; as such, ZIKV-induced glial dysfunctions can be associated with the development and progression of neurological complications, including those related to the adult and aging brain. This review will address the effects of ZIKV infection on CNS and PNS glial cells, focusing on cellular and molecular mechanisms, including changes in the inflammatory response, oxidative stress, mitochondrial dysfunction, Ca2+ and glutamate homeostasis, neural metabolism, and neuron-glia communication. Of note, preventive and therapeutic strategies that focus on glial cells may emerge to delay and/or prevent the development of ZIKV-induced neurodegeneration and its consequences.


Subject(s)
Zika Virus Infection , Zika Virus , Humans , Zika Virus/physiology , Zika Virus Infection/complications , Zika Virus Infection/drug therapy , Zika Virus Infection/pathology , Neuroglia/metabolism , Central Nervous System/metabolism , Brain/metabolism
4.
Arch Virol ; 168(2): 70, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36658439

ABSTRACT

Zika virus (ZIKV) is an arbovirus that was responsible for multiple outbreaks from 2007 to 2015. It has been linked to cases of microcephaly in Brazil in 2015, among other neurological disorders. Differences among strains might be the reason for different clinical outcomes of infection. To evaluate this hypothesis, we performed a comparative proteomic analysis of Vero cells infected with the African strain MR766 (ZIKVAFR) and the Brazilian strain 17 SM (ZIKVBR). A total of 550 proteins were identified as differentially expressed in ZIKVAFR- or ZIKVBR-infected cells compared to the control. The main findings included upregulation of immune system pathways (neutrophil degranulation and adaptive/innate immune system) and potential activation of immune-system-related pathways by ZIKVAFR (mTOR, JAK-STAT, NF-κB, and others) compared with the ZIKVBR/control. In addition, phagocytosis by macrophages and engulfment of leukocytes were activated in ZIKVAFR infection. An in vivo analysis using an immunocompetent C57BL/6N mouse model identified interstitial pneumonia with neutrophil infiltration in the lungs only in mice infected with ZIKVBR at 48 hours postinfection, with a significant amount of virus detected. Likewise, only animals infected with ZIKVBR had viral material in the cytoplasm of lung macrophages. These results suggest that activation of the immune system by ZIKVAFR infection may lead to faster viral clearance by immune cells.


Subject(s)
Immune Evasion , Zika Virus Infection , Zika Virus , Animals , Mice , Brazil , Chlorocebus aethiops , Mice, Inbred C57BL , Proteomics , Vero Cells , Zika Virus/physiology , Zika Virus Infection/immunology
5.
Int J Mol Sci ; 23(24)2022 Dec 09.
Article in English | MEDLINE | ID: mdl-36555275

ABSTRACT

Gastrointestinal diseases, such as peptic ulcers, are caused by a damage in the gastric mucosa provoked by several factors. This stomach injury is regulated by many inflammatory mediators and is commonly treated with proton-pump inhibitors, histamine H2 receptor blockers and antacids. However, various medicinal plants have demonstrated positive effects on gastric ulcer treatment, including plants of the Ceiba genus. The aim of this study was to evaluate the antiulcer and anti-inflammatory activities of the stem bark ethanolic extract of Ceiba speciosa (A. St.-Hil.) Ravenna. We performed a preliminary quantification of phenolic compounds by high-performance liquid chromatography-diode array detection (HPLC-DAD), followed by the prospection of other chemical groups through nuclear magnetic resonance (NMR) spectroscopy. A set of in vitro assays was used to evaluate the extract potential regarding its antioxidant activity (DPPH: 19.83 ± 0.34 µg/mL; TPC: 307.20 ± 6.20 mg GAE/g of extract), effects on cell viability and on the release of TNF-α in whole human blood. Additionally, in vivo assays were performed to evaluate the leukocyte accumulation and total protein quantification in carrageenan-induced air pouch, as well as the antiulcerogenic effect of the extract on an ethanol-induced ulcer in rats. The extract contains flavonoids and phenolic compounds, as well as sugars and quinic acid derivatives exhibiting potent antioxidant activity and low toxicity. The extract reduced the release of TNF-α in human blood and inhibited the activity of p38α (1.66 µg/mL), JAK3 (5.25 µg/mL), and JNK3 (8.34 µg/mL). Moreover, it reduced the leukocyte recruitment on the pouch exudate and the formation of edema, reverting the effects caused by carrageenan. The extract presented a significant prevention of ulcer formation and a higher reduction than the reference drug, Omeprazole. Therefore, C. speciosa extract has demonstrated relevant therapeutic potential for the treatment of gastric diseases, deserving the continuation of further studies to unveil the mechanisms of action of plant bioactive ingredients.


Subject(s)
Anti-Ulcer Agents , Ceiba , Plant Extracts , Stomach Ulcer , Animals , Humans , Rats , Anti-Ulcer Agents/pharmacology , Antioxidants/pharmacology , Carrageenan/adverse effects , Ceiba/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Stomach Ulcer/chemically induced , Stomach Ulcer/drug therapy , Tumor Necrosis Factor-alpha/metabolism , Ulcer
6.
J Cell Biochem ; 123(9): 1495-1505, 2022 09.
Article in English | MEDLINE | ID: mdl-35892149

ABSTRACT

Following health agencies warning, the use of animal origin supplements should be avoided in biological products proposed as therapy in humans. Platelet lysate and several other growth factors sources are alternatives to replace fetal calf serum, the current gold standard in clinical-grade cell culture. However, the platelet supplement's content lacks data due to different production methods. The principle behind these products relays on the lysis of platelets that release several proteins, some of which are contained in heterogeneous granules and coordinate biological functions. This study aims to analyze the composition and reproducibility of a platelet lysate produced with a standardized method, by describing several batches' protein and particle content using proteomics and dynamic light scattering. Proteomics data revealed a diversified protein content, with some related to essential cellular processes such as proliferation, morphogenesis, differentiation, biosynthesis, adhesion, and metabolism. It also detected proteins responsible for activation and binding of transforming growth factor beta, hepatocyte growth factor, and insulin-like growth factor. Total protein, biochemical, and growth factors quantitative data showed consistent and reproducible values across batches. Novel data on two major particle populations is presented, with high dispersion level at 231 ± 96 d.nm and at 30 ± 8 d.nm, possibly being an important way of protein trafficking through the cellular microenvironment. This experimental and descriptive analysis aims to support the content definition and quality criteria of a cell supplement for clinical applications.


Subject(s)
Biological Products , Mesenchymal Stem Cells , Somatomedins , Animals , Blood Platelets/metabolism , Cell Differentiation , Cell Proliferation , Cell- and Tissue-Based Therapy , Cells, Cultured , Culture Media/chemistry , Hepatocyte Growth Factor/metabolism , Humans , Mesenchymal Stem Cells/metabolism , Proteomics , Reproducibility of Results , Serum Albumin, Bovine/analysis , Serum Albumin, Bovine/metabolism , Somatomedins/analysis , Somatomedins/metabolism , Transforming Growth Factor beta/metabolism
7.
Braz J Microbiol ; 53(3): 1633-1643, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35704174

ABSTRACT

The acidity of soils significantly reduces the productivity of legumes mainly because of the detrimental effects of hydrogen ions on the legume plants, leading to the establishment of an inefficient symbiosis and poor biological nitrogen fixation. We recently reported the analysis of the fully sequenced genome of Rhizobium favelukesii LPU83, an alfalfa-nodulating rhizobium with a remarkable ability to grow, nodulate and compete in acidic conditions. To gain more insight into the genetic mechanisms leading to acid tolerance in R. favelukesii LPU83, we constructed a transposon mutant library and screened for mutants displaying a more acid-sensitive phenotype than the parental strain. We identified mutant Tn833 carrying a single-transposon insertion within LPU83_2531, an uncharacterized short ORF located immediately upstream from ubiF homolog. This gene encodes a protein with an enzymatic activity involved in the biosynthesis of ubiquinone. As the transposon was inserted near the 3' end of LPU83_2531 and these genes are cotranscribed as a part of the same operon, we hypothesized that the phenotype in Tn833 is most likely due to a polar effect on ubiF transcription.We found that a mutant in ubiF was impaired to grow at low pH and other abiotic stresses including 5 mM ascorbate and 0.500 mM Zn2+. Although the ubiF mutant retained the ability to nodulate alfalfa and Phaseolus vulgaris, it was unable to compete with the R. favelukesii LPU83 wild-type strain for nodulation in Medicago sativa and P. vulgaris, suggesting that ubiF is important for competitiveness. Here, we report for the first time an ubiF homolog being essential for nodulation competitiveness and tolerance to specific stresses in rhizobia.


Subject(s)
Rhizobium , Symbiosis , Acids/pharmacology , Medicago sativa/metabolism , Nitrogen Fixation/genetics , Rhizobium/genetics , Symbiosis/genetics
8.
World J Microbiol Biotechnol ; 38(7): 114, 2022 May 17.
Article in English | MEDLINE | ID: mdl-35578144

ABSTRACT

Burkholderia ambifaria T16 is a bacterium isolated from the rhizosphere of barley plants that showed a remarkable antifungal activity. This strain was also able to degrade fusaric acid (5-Butylpyridine-2-carboxylic acid) and detoxify this mycotoxin in inoculated barley seedlings. Genes and enzymes responsible for fusaric acid degradation have an important biotechnological potential in the control of fungal diseases caused by fusaric acid producers, or in the biodegradation/bio catalysis processes of pyridine derivatives. In this study, the complete genome of B. ambifaria T16 was sequenced and analyzed to identify genes involved in survival and competition in the rhizosphere, plant growth promotion, fungal growth inhibition, and degradation of aromatic compounds. The genomic analysis revealed the presence of several operons for the biosynthesis of antimicrobial compounds, such as pyrrolnitrin, ornibactin, occidiofungin and the membrane-associated AFC-BC11. These compounds were also detected in bacterial culture supernatants by mass spectrometry analysis. In addition, this strain has multiple genes contributing to its plant growth-promoting profile, including those for acetoin, 2,3-butanediol and indole-3-acetic acid production, siderophores biosynthesis, and solubilisation of organic and inorganic phosphate. A pan-genomic analysis demonstrated that the genome of strain T16 possesses large gene clusters that are absent in the genomes of B. ambifaria reference strains. According to predictions, most of these clusters would be involved in aromatic compounds degradation. One genomic region, encoding flavin-dependent monooxygenases of unknown function, is proposed as a candidate responsible for fusaric acid degradation.


Subject(s)
Anti-Infective Agents , Burkholderia cepacia complex , Burkholderia , Mycotoxins , Anti-Infective Agents/metabolism , Burkholderia/metabolism , Burkholderia cepacia complex/genetics , Fusaric Acid/metabolism , Genome, Bacterial , Mycotoxins/metabolism
9.
Front Genet ; 13: 758715, 2022.
Article in English | MEDLINE | ID: mdl-35350244

ABSTRACT

Five years after the identification of Zika virus as a human teratogen, we reviewed the early clinical manifestations, collectively called congenital Zika syndrome (CZS). Children with CZS have a very poor prognosis with extremely low performance in motor, cognitive, and language development domains, and practically all feature severe forms of cerebral palsy. However, these manifestations are the tip of the iceberg, with some children presenting milder forms of deficits. Additionally, neurodevelopment can be in the normal range in the majority of the non-microcephalic children born without brain or eye abnormalities. Vertical transmission and the resulting disruption in development of the brain are much less frequent when maternal infection occurs in the second half of the pregnancy. Experimental studies have alerted to the possibility of other behavioral outcomes both in prenatally infected children and in postnatal and adult infections. Cofactors play a vital role in the development of CZS and involve genetic, environmental, nutritional, and social determinants leading to the asymmetric distribution of cases. Some of these social variables also limit access to multidisciplinary professional treatment.

10.
Inflammopharmacology ; 30(2): 565-577, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35165808

ABSTRACT

Myrciaria plinioides D. Legrand (Myrtaceae) is a native plant of Southern Brazil, which have potential in the food industry due to its edible fruits. Many plants belonging to this genus have been used for a variety of illnesses, including inflammatory disorders due to antioxidant properties. However, therapeutic uses of M. plinioides have been poorly studied. The aim of study was to assess the anti-inflammatory and anticoagulant activities of the ethanol leaf extract of M. plinioides. In M. plinioides extract-treated RAW 264.7 cells, assessments of cell viability, TNF-α release and p38 MAPK pathway-dependent protein expression were detected. In addition, rat paw edema models were used to analyze the anti-inflammatory effect of the extract. Macrophages cell line treated with M. plinioides extract showed a slight decrease in cell viability. In LPS-stimulated macrophages treated with different concentrations of the extract for 24 h, TNF-α release was inhibited, while modulation of p38 signaling pathway and inhibition of NF-κB p65 protein expression were dose-dependent. In rats, the extract inhibited the formation of paw edema, while an inhibitory effect on trypsin-like enzymes derived from mast cells was seen. Furthermore, the extract presented anticoagulant activity via extrinsic pathway, being able to block specifically factor Xa and thrombin. The study suggests that extract possess potent anti-inflammatory and anticoagulant effects. M. plinioides present great biological potential as a source for the development of anti-inflammatory and anticoagulant drugs. Additional studies can be proposed to better elucidate the mechanism by which M. plinioides exerts its effects.


Subject(s)
Ethanol , Myrtaceae , Animals , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Anticoagulants/pharmacology , Lipopolysaccharides , NF-kappa B/metabolism , Nitric Oxide , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Rats
11.
J Med Case Rep ; 16(1): 39, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-35101107

ABSTRACT

BACKGROUND: Anaplastic thyroid carcinoma is a rare, rapidly progressive, and highly aggressive tumor. It has a global annual incidence of 1-2 per million people. It mostly affects older adults and women. The median survival duration after diagnosis does not exceed 6-8 months. CASE PRESENTATION: A 60-year-old female patient of mixed race (Honduran) presented to the local medical service with dysphonia that had started approximately 2 months earlier, accompanied by orthopnea that had started 1 month earlier. On physical examination, a soft mass was palpated within the anterior neck region; it was approximately 4 cm in diameter, painless, and mobile on swallowing, and had irregular margins. Ultrasound and computed tomography of the neck were performed. Subsequently, fine needle aspiration biopsy was performed. The histological diagnosis was anaplastic thyroid carcinoma (stage IVB). She underwent total thyroidectomy and chemotherapy. She is currently in her fifth year of remission after diagnosis and remains under oncologic surveillance. DISCUSSION: Anaplastic thyroid carcinoma demonstrates a lethal behavior. Approximately 18% survive for more than a year after diagnosis, and 0-10% survive for 5 years. Different pretherapeutic prognostic factors may affect survival, including age < 70 years, the absence of distant metastases, and complete local resection. CONCLUSION: Conventional treatment improves the quality of life of the patient, but the results are not encouraging for the medium and long term. Only a few patients manage to exceed the average life expectancy of 3-6 months, despite undergoing the currently available therapeutic regimen.


Subject(s)
Thyroid Carcinoma, Anaplastic , Thyroid Neoplasms , Aged , Female , Humans , Middle Aged , Quality of Life , Thyroid Carcinoma, Anaplastic/diagnostic imaging , Thyroid Carcinoma, Anaplastic/therapy , Thyroid Neoplasms/surgery , Thyroidectomy , Ultrasonography
13.
Ginecol. obstet. Méx ; Ginecol. obstet. Méx;90(4): 378-383, ene. 2022. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1385036

ABSTRACT

Resumen ANTECEDENTES: Los liposarcomas son un tipo de tumor de partes blandas. El subtipo desdiferenciado es una de las variantes más comunes junto con el liposarcoma bien diferenciado. CASO CLÍNICO: Paciente de 68 años que acudió a consulta por aparición de una masa en la zona vaginal que clínicamente se diagnosticó como hernia inguinal directa. Se procedió a la resección quirúrgica de la masa. El reporte histopatológico fue de miofibrolipoma, sin atipias y con bordes libres de neoplasia. Tres años después, la paciente retornó a la consulta por reaparición de la masa y se negó a una nueva biopsia. Posteriormente, en el 2020, la paciente aceptó la resección de la masa; el reporte histopatológico fue: liposarcoma desdiferenciado con diferenciación lipoblástica homóloga a liposarcoma pleomórfico. CONCLUSIÓN: Los estudios histopatológicos son necesarios para la confirmación del diagnóstico y la resección quirúrgica es el tratamiento de elección.


Abstract BACKGROUND: Liposarcomas are a type of soft tissue tumor. The dedifferentiated subtype is one of the most common variants along with well-differentiated liposarcoma. CLINICAL CASE: A 68-year-old female patient presented for consultation due to the appearance of a mass in the vaginal area which was clinically diagnosed as a direct inguinal hernia. Surgical resection of the mass was performed. The histopathological report was myofibrolipoma, without atypia and with borders free of neoplasia. Three years later, the patient returned to the office for recurrence of the mass and refused a new biopsy. Subsequently, in 2020, the patient accepted the resection of the mass; the histopathologic report was: dedifferentiated liposarcoma with lipoblastic differentiation homologous to pleomorphic liposarcoma. CONCLUSION: Histopathological studies are necessary for confirmation of the diagnosis and surgical resection is the treatment of choice.

14.
Vet World ; 14(10): 2699-2704, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34903928

ABSTRACT

BACKGROUND AND AIM: Momordica charantia is mainly characterized by its antimicrobial and antioxidant properties. The current study aimed to evaluate the healing activity of gel and cream formulations based on M. charantia on induced wounds in mice. MATERIALS AND METHODS: Acetonic extract of M. charantia was prepared and incorporated into gel and cream formulations. Mus musculus Balb/c (n=30) with induced injury were distributed into five groups: Group I (control - day 7), Group II (control - day 14), Group III (1% gel - day 7), and Group IV (1% gel - day 14) to which 1% M. charantia gel was dermally applied daily for 7 and 14 days, respectively, Group V (1% cream - day 7) and Group VI (1% cream - day 14) to which of M. charantia 1% cream were dermally applied daily for 7 and 14 days, respectively. Time of wound closure was determined during the experimentation; rats were euthanized with sodium pentobarbital 60 mg/kg/pc v.ip. for obtaining skin samples for histopathological analysis. RESULTS: Groups IV and VI showed a higher percentage of wound closure on day 14, and in histopathological analysis, effect was greater in Group VI with the presence of fibroblasts and abundant collagen and elastic fibers. CONCLUSION: M. charantia gel and cream showed wound healing activity on induced wounded mice; the most effective treatment was M. charantia 1% cream formulation.

16.
Neuroimmunomodulation ; 28(4): 229-232, 2021.
Article in English | MEDLINE | ID: mdl-34082423

ABSTRACT

INTRODUCTION: The aim of this case was to investigate the association of the Zika virus infection in utero with the autism spectrum disorder (ASD) as clinical outcome that presented no congenital anomalies. METHODS: ASD was diagnosed in the second year of life by different child neurologists and confirmed by DSM-5 and ASQ. After that, an extensive clinical, epidemiological, and genetic evaluations were performed, with main known ASD causes ruled out. RESULTS: An extensive laboratorial search was done, with normal findings. SNP array identified no pathogenic variants. Normal neuroimaging and EEG findings were also obtained. ZIKV (Zika virus) IgG was positive, while IgM was negative. Other congenital infections were negative. The exome sequencing did not reveal any pathogenic variant in genes related to ASD. CONCLUSION: Accordingly, this report firstly associates ZIKV exposure to ASD.


Subject(s)
Autism Spectrum Disorder , Pregnancy Complications, Infectious , Zika Virus Infection , Zika Virus , Autism Spectrum Disorder/complications , Autism Spectrum Disorder/genetics , Child , Female , Humans , Pregnancy , Zika Virus/genetics , Zika Virus Infection/complications
18.
J Biotechnol ; 329: 80-91, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33539896

ABSTRACT

The nitrogen-fixing α-proteobacterium Sinorhizobium meliloti genome codifies at least 50 response regulator (RR) proteins mediating different and, in many cases, unknown processes. RR-mutant library screening allowed us to identify genes potentially implicated in survival to acid conditions. actJ mutation resulted in a strain with reduced growth rate under mildly acidic conditions as well as a lower capacity to tolerate a sudden shift to lethal acidic conditions compared with the parental strain. Mutation of the downstream gene actK, which encodes for a histidine kinase, showed a similar phenotype in acidic environments suggesting a functional two-component system. Interestingly, even though nodulation kinetics, quantity, and macroscopic morphology of Medicago sativa nodules were not affected in actJ and actK mutants, ActK was required to express the wild-type nitrogen fixation phenotype and ActJK was necessary for full bacteroid development and nodule occupancy. The actJK regulatory system presented here provides insights into an evolutionary process in rhizobium adaptation to acidic environments and suggests that actJK-controlled functions are crucial for optimal symbiosis development.


Subject(s)
Sinorhizobium meliloti , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Medicago sativa/metabolism , Nitrogen Fixation , Sinorhizobium meliloti/genetics , Sinorhizobium meliloti/metabolism , Symbiosis/genetics
19.
Cienc. tecnol. salud ; 8(1): 82-92, 2021. il 27 c
Article in Spanish | LILACS, DIGIUSAC, LIGCSA | ID: biblio-1352960

ABSTRACT

Se determinó la respuesta inmunológica a proteínas recombinantes de Helicobacter pylori en pacientes dis-pépticos (adultos y niños), pacientes con cáncer gástrico y sus familiares asintomáticos adultos viviendo con ellos. Se utilizó la prueba recomLine® Helicobacter IgG e IgA, y con base en el reconocimiento de los factores de virulencia VacA y CagA se determinó si la cepa de H. pylori era de tipo I o II. El análisis de los datos fue descriptivo y analítico y se estimaron los intervalos de confianza de 95%, con un nivel de error de 0.05 y Odds ratio. El 58.7% (121/206) de los pacientes presentó la bacteria en tinción histológica de biopsia, positividad que disminuyó con la edad y daño histológico. La frecuencia de la respuesta a los anticuerpos IgG fue mayor que IgA, en ambos casos ésta fue menor en los niños. Las proteínas del H. pylori más reconocidas tanto por IgA como IgG fueron VacA y CagA, y la respuesta a las otras proteínas investigadas fue mayor al aumentar el daño histológi-co. La cepa tipo I fue la que predominó en la población en estudio con 66% (136/206). Se deben continuar con los estudios de prevalencia de la cepa tipo I del H. pylori y del reconocimiento de sus antígenos en la población guatemalteca a fin de determinar su utilidad en el diagnóstico y pronóstico de la infección.


The immune response to recombinant Helicobacter pylori proteins was determined in dyspeptic patients (adults and children), patients with gastric cancer and their asymptomatic adults' relatives living with them. The recomLine® Helicobacter IgG and IgA test was used and based on the recognition of the virulence factors VacA and CagA, it was determined whether the H. pylori strain was type I or II. The data analysis was descriptive and analytic, and 95% confidence intervals were estimated, with an error level of 0.05, and Odds ratio. The patients that presented the bacterium in histological biopsy were 58.7% (121/206), positivity that decreased with age and histological damage. The frecuency of response to IgG antibodies was higher than IgA, in both cases it was lower in children. VacA and CagA were the H. pylori proteins most recognized by both IgA and IgG and it was observed that the number of recognized proteins was greater with increasing histological damage. The type I strain was the one that predominated in the study population 66% (136/206). Prevalence studies of the type I strain of H. pylori ant the recognition of its antigens in the Guatemalan population should continue in order to determine its usefulness in the diagnosis and prognosis of infection.


Subject(s)
Humans , Child , Adult , Stomach Neoplasms/immunology , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Helicobacter pylori/immunology , Dyspepsia/immunology , Stomach Neoplasms/microbiology , Stomach Neoplasms/pathology , Biopsy , Recombinant Proteins/analysis , Recombinant Proteins/immunology , Immunoglobulin A/analysis , Immunoglobulin G/analysis , Helicobacter pylori/isolation & purification , Helicobacter pylori/pathogenicity , Dyspepsia/microbiology , Dyspepsia/pathology , Guatemala
20.
Sci Rep ; 10(1): 21604, 2020 12 10.
Article in English | MEDLINE | ID: mdl-33303883

ABSTRACT

Zika virus (ZIKV) infection during pregnancy was associated with microcephaly in neonates, but clinical and experimental evidence indicate that ZIKV also causes neurological complications in adults. However, the changes in neuron-glial communication, which is essential for brain homeostasis, are still unknown. Here, we report that hippocampal slices from adult rats exposed acutely to ZIKV showed significant cellular alterations regarding to redox homeostasis, inflammatory process, neurotrophic functions and molecular signalling pathways associated with neurons and glial cells. Our findings support the hypothesis that ZIKV is highly neurotropic and its infection readily induces an inflammatory response, characterized by an increased expression and/or release of pro-inflammatory cytokines. We also observed changes in neural parameters, such as adenosine receptor A2a expression, as well as in the release of brain-derived neurotrophic factor and neuron-specific enolase, indicating plasticity synaptic impairment/neuronal damage. In addition, ZIKV induced a glial commitment, with alterations in specific and functional parameters such as aquaporin 4 expression, S100B secretion and glutathione synthesis. ZIKV also induced p21 senescence-associated gene expression, indicating that ZIKV may induce early senescence. Taken together, our results indicate that ZIKV-induced neuroinflammation, involving nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor κB (NFκB) pathways, affects important aspects of neuron-glia communication. Therefore, although ZIKV infection is transient, long-term consequences might be associated with neurological and/or neurodegenerative diseases.


Subject(s)
Cell Communication , Hippocampus/pathology , Neuroglia/pathology , Neurons/pathology , Zika Virus Infection/pathology , Zika Virus/pathogenicity , Animals , Female , Male , Pregnancy , Rats , Rats, Wistar
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