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1.
J Pain ; 25(8): 104508, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38484854

RESUMO

Postamputation pain is currently managed unsatisfactorily with neuron-targeted pharmacological and interventional therapies. Non-neuronal pain mechanisms have emerged as crucial factors in the development and persistence of postamputation pain. Consequently, these mechanisms offer exciting prospects as innovative therapeutic targets. We examined the hypothesis that engaging mesenchymal stem cells (MSCs) would foster local neuroimmune interactions, leading to a potential reduction in postamputation pain. We utilized an ex vivo neuroma model from a phantom limb pain patient to uncover that the oligodeoxynucleotide IMT504 engaged human primary MSCs to promote an anti-inflammatory microenvironment. Reverse translation experiments recapitulated these effects. Thus, in an in vivo rat model, IMT504 exhibited strong efficacy in preventing autotomy (self-mutilation) behaviors. This effect was linked to a substantial accumulation of MSCs in the neuroma and associated dorsal root ganglia and the establishment of an anti-inflammatory phenotype in these compartments. Centrally, this intervention reduced glial reactivity in the dorsal horn spinal cord, demonstrating diminished nociceptive activity. Accordingly, the exogenous systemic administration of MSCs phenocopied the behavioral effects of IMT504. Our findings underscore the mechanistic relevance of MSCs and the translational therapeutic potential of IMT504 to engage non-neuronal cells for the prevention of postamputation pain. PERSPECTIVE: The present study suggests that IMT504-dependent recruitment of endogenous MSCs within severely injured nerves may prevent post-amputation pain by modifying the inflammatory scenario at relevant sites in the pain pathway. Reinforcing data in rat and human tissues supports the potential therapeutic value of IMT504 in patients suffering postamputation pain.


Assuntos
Transplante de Células-Tronco Mesenquimais , Neuroma , Membro Fantasma , Animais , Humanos , Ratos , Masculino , Membro Fantasma/fisiopatologia , Membro Fantasma/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Ratos Sprague-Dawley , Modelos Animais de Doenças , Feminino , Gânglios Espinais , Dor Pós-Operatória , Amputação Cirúrgica
2.
Polymers (Basel) ; 15(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37447552

RESUMO

Poly(3-hydroxybutyrate), PHB, is a hydrophobic biopolymer with good mechanical and barrier properties. However, neat PHB is a semicrystalline polymer with a relative high degree of crystallinity and poor film properties. In this work, this biopolymer was plasticized with glycerol tributyrate and functionalized with copper (II) sulfate, allowing us to obtain biodegradable antimicrobial flexible films. Films with the minimum inhibitory concentration (MIC) of copper (II) sulfate presented a higher roughness than neat PHB films. The presence of plasticizer significantly improved the copper sulfate diffusion process, which was evidenced by a greater inhibition halo for plasticized materials compared to unplasticized ones, at the same salt concentration. Plasticized PHB with 2.5% copper (II) sulfate inhibited both Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomona aeruginosa) bacteria, as determined by the bacterial inhibition halo. In addition, neat PHB films and PHB containing copper (II) sulfate did not show in vitro cytotoxicity in the L-929 cell line. Thus, plasticized PHB functionalized with copper (II) sulfate can be used as biodegradable antimicrobial flexible films for different applications.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36946333

RESUMO

This work investigated the synthesis and characterization of alginate/starch porous materials and their application as copper ions adsorbents from aqueous media. Initially, pregel aqueous solutions with different biopolymer concentrations (1, 3, and 5% w/w) and alginate contents (25, 50, and 75% w/w) were prepared. Hydrogel formation was performed by internal and external gelation methods. Finally, the drying step was done via CO2sc leading to aerogels and via freeze-drying leading to cryogels. Process parameters influence on the final properties of materials was evaluated by BET isotherms, SEM, EDS, and TGA. Regardless the gelation method applied, interesting materials with meso- and macro-pore structure were prepared from pregel mixtures with 3% w/w biopolymer concentration and an alginate content of only 25% w/w. Low alginate content reduces the final cost of the materials. Concerning copper removal, the adsorption data were well fitted to the pseudo-second order kinetic model for aerogels and cryogels, showing aerogels the highest adsorption capacity (40 mg/g) and removal efficiency (∼ 92%). Materials demonstrated excellent reusability throughout five consecutive adsorption/desorption cycles. Hence, environmentally friendly materials with a high practical value as low-cost bioadsorbents were synthesized, having great performance in the removal of copper ions from aqueous solution.


Assuntos
Alginatos , Cobre , Poluentes Químicos da Água , Adsorção , Alginatos/química , Cobre/química , Criogéis/química , Amido , Água/química , Poluentes Químicos da Água/química
5.
J Pain ; 24(6): 991-1008, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36706889

RESUMO

Despite the available knowledge on underlying mechanisms and the development of several therapeutic strategies, optimal management of postoperative pain remains challenging. This preclinical study hypothesizes that, by promoting an anti-inflammatory scenario, pre-emptive administration of IMT504, a noncoding, non-CpG oligodeoxynucleotide with immune modulating properties, will reduce postincisional pain, also facilitating therapeutic opioid-sparing. Male adult Sprague-Dawley rats with unilateral hindpaw skin-muscle incision received pre-emptive (48 and 24 hours prior to surgery) or postoperative (6 hours after surgery) subcutaneous vehicle (saline) or IMT504. Various groups of rats were prepared for pain-like behavior analyses, including subgroups receiving morphine or naloxone, as well as for flow-cytometry or quantitative RT-PCR analyses of the spleen and hindpaws (for analysis of inflammatory phenotype). Compared to vehicle-treated rats, pre-emptive IMT504 significantly reduced mechanical allodynia by 6 hours after surgery, and accelerated recovery of basal responses from 72 hours after surgery and onwards. Cold allodynia was also reduced by IMT504. Postoperative administration of IMT504 resulted in similar positive effects on pain-like behavior. In IMT504-treated rats, 3 mg/kg morphine resulted in comparable blockade of mechanical allodynia as observed in vehicle-treated rats receiving 10 mg/kg morphine. IMT504 significantly increased hindpaw infiltration of mesenchymal stem cells, CD4+T and B cells, and caused upregulated or downregulated transcript expressions of interleukin-10 and interleukin-1ß, respectively. Also, IMT504 treatment targeted the spleen, with upregulated or downregulated transcript expressions, 6 hours after incision, of interleukin-10 and interleukin-1ß, respectively. Altogether, pre-emptive or postoperative IMT504 provides protection against postincisional pain, through participation of significant immunomodulatory actions, and exhibiting opioid-sparing effects. PERSPECTIVE: This preclinical study introduces the noncoding non-CpG oligodeoxynucleotide IMT504 as a novel modulator of postoperative pain and underlying inflammatory events. The opioid-sparing effects observed for IMT504 appear as a key feature that could contribute, in the future, to reducing opioid-related adverse events in patients undergoing surgical intervention.


Assuntos
Analgésicos Opioides , Hiperalgesia , Ratos , Masculino , Animais , Analgésicos Opioides/farmacologia , Analgésicos Opioides/uso terapêutico , Hiperalgesia/tratamento farmacológico , Ratos Sprague-Dawley , Interleucina-10 , Interleucina-1beta , Dor Pós-Operatória/tratamento farmacológico , Morfina/farmacologia , Morfina/uso terapêutico , Oligodesoxirribonucleotídeos/uso terapêutico
6.
Exp Neurol ; 359: 114232, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36179876

RESUMO

Chemotherapy-induced neuropathic pain is a serious clinical problem and one of the major side effects in cancer treatment. The endocannabinoid system (ECS) plays a crucial role in regulating pain neurotransmission, and changes in the expression of different components of the ECS have been reported in experimental models of persistent pain. In addition, sex differences have been observed in ECS regulation and function. The aim of our study was to evaluate whether administration of oxaliplatin, a neurotoxic antineoplastic agent, induced changes in the expression of ECS components in peripheral and central stations of the pain pathway, and if those changes exhibited sexual dimorphism. Adult male and female rats were injected with oxaliplatin or saline, and mechanical and cold hypersensitivity and allodynia were evaluated using Von Frey and Choi Tests. The mRNA levels corresponding to cannabinoid receptors (CB1, CB2), cannabinoid-related receptors (GPR55, 5HT1A, TRPV1) and to the main enzymes involved in the synthesis (DAGL, DAGL, NAPE-PLD) and degradation (MGL, FAAH) of endocannabinoids were assessed in lumbar dorsal root ganglia (DRGs) and spinal cord by using real time RT-PCR. In addition, the levels of the main endocannabinoids, 2-arachidonoylglycerol (2-AG) and anandamide (AEA), were evaluated using commercial ELISA kits. Oxaliplatin administration induced the development of mechanical and cold hypersensitivity and allodynia in male and female animals. Oxaliplatin also induced early and robust changes in the expression of several components of the ECS in DRGs. A marked upregulation of CB1, CB2, 5HT1A and TRPV1 was detected in both sexes. Interestingly, while DAGL mRNA levels remained unchanged, DAGL was downregulated in male and upregulated in female rats. Finally, MGL and NAPE-PLD showed increased levels only in male animals, while FAAH resulted upregulated in both sexes. In parallel, reduced 2-AG and AEA levels were detected in DRGs from male or female rats, respectively. In the lumbar spinal cord, only TRPV1 mRNA levels were found to be upregulated in both sexes. Our results reveal previously unreported changes in the expression of cannabinoid receptors, ligands and enzymes occurring mainly in the peripheral nervous system and displaying certain sexual dimorphism. These changes may contribute to the physiopathology of oxaliplatin-induced neuropathic pain in male and female rats. A better understanding of these dynamic changes will facilitate the development of mechanism- and sex-specific approaches to optimize the use of cannabinoid-based medicines for the treatment of chemotherapy-induced pain.


Assuntos
Antineoplásicos , Canabinoides , Neuralgia , Feminino , Masculino , Ratos , Animais , Endocanabinoides/metabolismo , Endocanabinoides/uso terapêutico , Caracteres Sexuais , Hiperalgesia/metabolismo , Oxaliplatina/toxicidade , Canais de Cátion TRPV/metabolismo , Neuralgia/metabolismo , Receptores de Canabinoides/metabolismo , Antineoplásicos/toxicidade , Antineoplásicos/uso terapêutico , RNA Mensageiro , Modelos Teóricos , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/uso terapêutico , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/metabolismo
7.
Neurosci Lett ; 788: 136863, 2022 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-36067900

RESUMO

Transient receptor potential (TRP) channels are involved in the development of oxaliplatin-induced neuropathic pain, a frequent and debilitating side effect of cancer therapy. Here we explored whether oxaliplatin-induced changes in the expression of TRP channels, as well as the development of pain-related behaviours, differed between male and female animals. Adult rats were injected with oxaliplatin or saline and mechanical and cold allodynia were evaluated using Von Frey and Choi Tests. The mRNA levels of TRPV1, TRPM8 and TRPA1 were assessed in lumbar ganglia and spinal cord by using real time RT-PCR. Oxaliplatin administration induced mechanical and cold hypersensitivity and allodynia in both sexes, with more severe responses to cold stimulation detected in females. Oxaliplatin also induced a significant increase in the expression of TRPV1, TRPM8 and TRPA1 in lumbar dorsal root ganglia. Interestingly, while TRPV1 and TRPA1 upregulation showed no sex difference, the increase in TRPM8 mRNA levels was more pronounced in female ganglia, correlating with the increased sensitivity to innocuous cold stimuli observed in females. TRPV1 and TRPM8 were also found to be upregulated in the spinal cord of animals of both sexes. Our results reveal previously undescribed changes in the expression of TRP channels occurring in peripheral ganglia and spinal cord of both male and female oxaliplatin-treated animals, with some of these changes exhibiting sex-related differences that could underlie the development of sex-specific patterns of pain-related behaviours.


Assuntos
Neuralgia , Canais de Cátion TRPM , Canais de Potencial de Receptor Transitório , Animais , Temperatura Baixa , Síndromes Periódicas Associadas à Criopirina , Feminino , Gânglios Espinais/metabolismo , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Masculino , Neuralgia/metabolismo , Compostos Organoplatínicos/efeitos adversos , Compostos Organoplatínicos/metabolismo , Oxaliplatina/efeitos adversos , RNA Mensageiro/metabolismo , Ratos , Canal de Cátion TRPA1/metabolismo , Canais de Cátion TRPM/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo
8.
Pain ; 163(6): 1114-1129, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34711765

RESUMO

ABSTRACT: IMT504, a noncoding, non-CpG oligodeoxynucleotide, modulates pain-like behavior in rats undergoing peripheral nerve injury, through mechanisms that remain poorly characterized. Here, we chose the spared nerve injury model in rats to analyze the contribution of mesenchymal stem cells (MSCs) in the mechanisms of action of IMT504. We show that a single subcutaneous administration of IMT504 reverses mechanical and cold allodynia for at least 5 weeks posttreatment. This event correlated with long-lasting increases in the percentage of MSCs in peripheral blood and injured sciatic nerves, in a process seemingly influenced by modifications in the CXCL12-CXCR4 axis. Also, injured nerves presented with reduced tumor necrosis factor-α and interleukin-1ß and increased transforming growth factor-ß1 and interleukin-10 protein levels. In vitro analysis of IMT504-pretreated rat or human MSCs revealed internalized oligodeoxynucleotide and confirmed its promigratory effects. Moreover, IMT504-pretreatment induced transcript expression of Tgf-ß1 and Il-10 in MSCs; the increase in Il-10 becoming more robust after exposure to injured nerves. Ex vivo exposure of injured nerves to IMT504-pretreated MSCs confirmed the proinflammatory to anti-inflammatory switch observed in vivo. Interestingly, the sole exposure of injured nerves to IMT504 also resulted in downregulated Tnf-α and Il-1ß transcripts. Altogether, we reveal for the first time a direct association between the antiallodynic actions of IMT504, its promigratory and cytokine secretion modulating effects on MSCs, and further anti-inflammatory actions at injured nerves. The recapitulation of key outcomes in human MSCs supports the translational potential of IMT504 as a novel treatment for neuropathic pain with a unique mechanism of action involving the regulation of neuroimmune interactions.


Assuntos
Hiperalgesia , Células-Tronco Mesenquimais , Animais , Anti-Inflamatórios , Hiperalgesia/etiologia , Hiperalgesia/terapia , Interleucina-10 , Oligodesoxirribonucleotídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Am J Perinatol ; 39(11): 1248-1253, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33454946

RESUMO

OBJECTIVE: This study was aimed to explore the attitude of Argentinean neonatologists in the delivery room on resuscitating infants with trisomies. STUDY DESIGN: An anonymous questionnaire was completed by neonatologists staffing level-III neonatal intensive care units (NICUs) on resuscitation of children with trisomies 21, 18, and 13. Potential sociocultural factors influencing the decision to resuscitate were included. RESULTS: Overall, 314 neonatologists in 34 units in the Buenos Aires region participated (response rate of 54%). The position of neonatologists regarding the resuscitation in the delivery room was that 98% would resuscitate newborns with trisomy 21, and 47% with trisomy 18 or trisomy 13. Resuscitation of newborns with trisomy 18 or trisomy 13 by neonatologists was significantly associated with working in the public sector, religious beliefs, and legal framework. CONCLUSION: With improvement in the management and treatment of infants with trisomies 18 and 13, Argentinean neonatologists showed a favorable attitude toward resuscitating them in the delivery room. KEY POINTS: · We explored the attitudes of Argentinean neonatologists on resuscitation of children with trisomies.. · Half of neonatologists would resuscitate newborns with trisomies18 and 13.. · These results suggest an ongoing paradigm shift of the most severe trisomies..


Assuntos
Síndrome de Down , Neonatologistas , Atitude do Pessoal de Saúde , Criança , Humanos , Recém-Nascido , Ressuscitação , Inquéritos e Questionários , Trissomia , Síndrome da Trissomia do Cromossomo 13 , Síndrome da Trissomía do Cromossomo 18
10.
J Neuroimmune Pharmacol ; 16(3): 651-666, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33221983

RESUMO

IMT504 is a non-CPG, non-coding synthetic oligodeoxinucleotide (ODN) with immunomodulatory properties and a novel inhibitory role in pain transmission, exerting long-lasting analgesic effects upon multiple systemic administrations. However, its mechanisms of anti-nociceptive action are still poorly understood. In the present study in male adult rats undergoing complete Freund's adjuvant-induced hindpaw inflammation, we focused in the analysis of the immunomodulatory role of IMT504 over the cellular infiltrate, the impact on the inflammatory milieu, and the correlation with its anti-allodynic role. By means of behavioral analysis, we determined that a single subcutaneous administration of 6 mg/kg of IMT504 is sufficient to exert a 6-week-long full reversal of mechanical and cold allodynia, compromising neither acute pain perception nor locomotor activity. Importantly, we found that the anti-nociceptive effects of systemic IMT504, plus quick reductions in hindpaw edema, were associated with a modulatory action upon cellular infiltrate of B-cells, macrophages and CD8+ T-cells populations. Accordingly, we observed a profound downregulation of several inflammatory leukocyte adhesion proteins, chemokines and cytokines, as well as of ß-endorphin and an increase in the anti-inflammatory cytokine, interleukin-10. Altogether, we demonstrate that at least part of the anti-nociceptive actions of IMT504 relate to the modulation of the peripheral immune system at the site of injury, favoring a switch from pro- to anti-inflammatory conditions, and provide further support to its use against chronic inflammatory pain. Graphical abstract GA short description - IMT504 systemic Administration. Systemic administration of the non-CpG ODN IMT504 results in a 6-week long blockade of pain-like behavior in association with anti-inflammatory responses at the site of injury. These include modulation of lymphoid and myeloid populations plus downregulated expression levels of multiple pro-inflammatory cytokines and ß-endorphin. Nocifensive responses and locomotion remain unaltered.


Assuntos
Analgesia , Dor Crônica , Animais , Linfócitos T CD8-Positivos , Dor Crônica/tratamento farmacológico , Modelos Animais de Doenças , Hiperalgesia , Inflamação/tratamento farmacológico , Masculino , Oligodesoxirribonucleotídeos , Ratos
11.
Bioresour Bioprocess ; 8(1): 130, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38650284

RESUMO

This work aimed to study the feasibility of using vinasse for polyhydroxybutyrate (PHB) production by Bacillus megaterium. To optimize the culture medium, a Box-Behnken design was employed considering carbon (C), nitrogen (N), and phosphorus (Ph) concentrations as independent variables and PHB productivity as the response variable. The productivity decreased when C or N were increased, probably due to the presence of phenolic compounds and the limitation of N for the production of PHB by Bacillus sp. bacteria. An additional experimental design to optimize the C/N ratio and growing conditions (fermentation time and temperature) was carried out. Fermentation time had a statistically significant effect on PHB productivity reaching 10.6 mg/L h. On the other hand, the variability in physicochemical properties of vinasse samples led to significant differences in PHB productivity. Lower productivity values were obtained when vinasse had higher values of DBO. Therefore, biopolymers production from vinasse is a feasible alternative to valorize this bioethanol by-product.

12.
Early Hum Dev ; 142: 104955, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32006786

RESUMO

OBJECTIVE: To explore the ethical beliefs and attitudes of Argentinean neonatologists regarding limitation of life-sustaining treatment (LST) for very sick infants. METHODS: We used an anonymous questionnaire including direct questions and hypothetical clinical cases (inevitable demise and anticipated survival with severe long-term disability). Multivariable analysis was carried out to assess the relation between type of clinical case and physicians' LST attitudes. RESULTS: Overall, 315 neonatologists in 34 units in the Buenos Aires region participated (response rate 54%). Most responders would agree with decisions to start or continue LST. In both clinical cases, continuing current treatment with no therapeutic escalation was the only form of LST limitation acceptable to a substantial proportion (about 60%) of neonatologists. Agreement with LST limitation was slightly but significantly more likely when death was inevitable. CONCLUSION: Argentinean neonatologists showed a conservative attitude regarding LST limitation. Patient prognosis and options of non-treatment decision significantly influenced their choices.


Assuntos
Terapia Intensiva Neonatal/ética , Neonatologistas/psicologia , Suspensão de Tratamento/ética , Adulto , Argentina , Tomada de Decisão Clínica , Cultura , Feminino , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Recusa em Tratar/ética
13.
Bioresour Technol ; 289: 121699, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323726

RESUMO

In this work, we propose a Mixed Integer Nonlinear Programming (MINLP) model to determine the optimal design of a poly(hydroxyalkanoate)s (PHAs) production plant configuration. The superstructure based optimization model considers different carbon sources as raw material: glycerol (crude and purified), corn starch, cassava starch, sugarcane sucrose and sugarcane molasses. The PHA extraction section includes four alternatives: the use of enzyme, solvent, surfactant-NaOCl or surfactant-chelate. Model constraints include detailed capital cost for equipment, mass and energy balances, product specifications and operating bounds on process units. The resulting MINLP model maximizes the project net present value (NPV) as objective function and it is implemented in an equation oriented environment. Optimization results show the sugarcane-enzyme option as the most promising alternative (NPV = 75.01 million USD) for PHAs production with an energy consumption of 22.56 MJ/kg PHA and a production cost of 3.02 USD/kg PHA. Furthermore, an economic sensitivity analysis is performed.


Assuntos
Poli-Hidroxialcanoatos/biossíntese , Carbono/metabolismo , Glicerol/metabolismo , Melaço , Amido/metabolismo
14.
Heliyon ; 5(6): e01877, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31211261

RESUMO

A structural study about the changes induced by plasticization of native corn starch was carried out in this work. The influence of talc nanoparticles presence during starch thermal processing was also evaluated. Macroscopic observation of the granules appearance evolution during melt-mixing and thermo-compression was supported by a theoretical description related to these processing methods. Melt-mixing induced a polymorphic transformation from A- to Vh-type and a reduction in the degree of crystallinity. Homogenous appearance of the plasticized starch was in accordance to the disruption of granules integrity, evidenced by SEM. This observation agreed to the distinctive XRD pattern of plasticized starch from unprocessed granules. Talc incorporation did not require the adjustment of processing parameters in order to obtain a homogenous thermoplastic material, with an adequate particles distribution within the matrix. Regardless talc presence, plasticized starch presented a Vh-type crystalline structure. Thermo-compression led to particles alignment promoted by talc laminar morphology.

15.
J Peripher Nerv Syst ; 24(1): 100-110, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30680838

RESUMO

Chemotherapy-induced peripheral neuropathy is a disabling condition induced by several frequently used chemotherapeutic drugs including the front-line agent oxaliplatin (OXA). Symptoms are predominantly sensory with the development of neuropathic pain. Alternative dosing protocols and treatment discontinuation are the only available therapeutic strategies. The aim of our work was to evaluate the potential of a synthetic derivative of progesterone, 17α-hydroxyprogesterone caproate (HPGC), in the prevention and treatment of OXA-evoked painful neuropathy. We also evaluated glial activation at the dorsal root ganglia (DRG) and spinal cord levels as a possible target mechanism underlying HPGC actions. Male rats were injected with OXA and HPGC following a prophylactic (HPGCp) or therapeutic (HPGCt) scheme (starting either before or after chemotherapy). The development of hypersensitivity and allodynic pain and the expression of neuronal and glial activation markers were evaluated. When compared to control animals, those receiving OXA showed a significant decrease in paw mechanical and thermal thresholds, with the development of allodynia. Animals treated with HPGCp showed patterns of response similar to those detected in control animals, while those treated with HPGCt showed a suppression of both hypersensitivities after HPGC administration. We also observed a significant increase in the mRNA levels of activating transcription factor 3, the transcription factor (c-fos), glial fibrillary acidic protein, ionized calcium binding adaptor protein 1, interleukin 1 beta (IL-1ß) and tumor necrosis factor alpha (TNFα) in DRG and spinal cord of OXA-injected animals, and significantly lower levels in rats receiving OXA and HPGC. These results show that HPGC administration reduces neuronal and glial activation markers and is able to both prevent and suppress OXA-induced allodynia, suggesting a promising therapeutic strategy.


Assuntos
Caproato de 17 alfa-Hidroxiprogesterona/farmacologia , Antineoplásicos/farmacologia , Hiperalgesia , Neuralgia , Oxaliplatina/farmacologia , Doenças do Sistema Nervoso Periférico , Progestinas/farmacologia , Caproato de 17 alfa-Hidroxiprogesterona/administração & dosagem , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Hiperalgesia/prevenção & controle , Masculino , Neuralgia/induzido quimicamente , Neuralgia/tratamento farmacológico , Neuralgia/prevenção & controle , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/prevenção & controle , Progestinas/administração & dosagem , Ratos , Ratos Sprague-Dawley
16.
Environ Technol ; 40(9): 1185-1202, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29243993

RESUMO

Poly(hydroxybutyrate-co-hydroxyvalerate) (P(HB-co-HV)) is a prominent biopolymer as a potential candidate for use in the biomedical area. Several Bacillus spp. strains show promising characteristics in the use of several carbon sources and are an interesting alternative for the production of P(HB-co-HV). Sewage from the agricultural and food processing industries can be used to obtain abundantly starch as a carbon source for PHA production. The aim of the present study was to optimize by response surface methodology and desirability, the production of PHA by a Bacillus megaterium strain using starch as the sole carbon source. Two optimal conditions were determined without sporulation and were used to perform new experiments to calibrate and validate a mechanistic model, developed to simulate the dynamics of PHA and biomass production. The developed model successfully represents the kinetics of the microorganism. Employing different characterization techniques, it was determined that the PHA produced by the strain is a copolymer composed of different HB:HV proportions. Using starch as the sole carbon source in a minimal salt medium, this work shows the first reports in the literature of: 1) a mathematical model for predicting growth kinetic and PHA production for B. megaterium strain and 2) a Bacillus spp. producing P(HB-co-HV) copolymer.


Assuntos
Bacillus megaterium , Poliésteres , Projetos de Pesquisa , Amido
17.
J Microbiol Methods ; 148: 1-11, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29580981

RESUMO

The presence of intracellular polyhydroxyalkanoates (PHAs) is usually studied using Sudan black dye solution (SB). In a previous work it was shown that the PHA could be directly quantified using the absorbance of SB fixed by PHA granules in wet cell samples. In the present paper, the optimum SB amount and the optimum conditions to be used for SB assays were determined following an experimental design by hybrid response surface methodology and desirability-function. In addition, a new methodology was developed in which it is shown that the amount of SB fixed by PHA granules can also be determined indirectly through the absorbance of the supernatant obtained from the stained cell samples. This alternative methodology allows a faster determination of the PHA content (involving 23 and 42 min for indirect and direct determinations, respectively), and can be undertaken by means of basic laboratory equipment and reagents. The correlation between PHA content in wet cell samples and the spectra of the SB stained supernatant was determined by means of multivariate and linear regression analysis. The best calibration adjustment (R2 = 0.91, RSE: 1.56%), and the good PHA prediction obtained (RSE = 1.81%), shows that the proposed methodology constitutes a reasonably precise way for PHA content determination. Thus, this methodology could anticipate the probable results of the above mentioned direct PHA determination. Compared with the most used techniques described in the scientific literature, the combined implementation of these two methodologies seems to be one of the most economical and environmentally friendly, suitable for rapid monitoring of the intracellular PHA content.


Assuntos
Compostos Azo/metabolismo , Bacillus megaterium/química , Naftalenos/metabolismo , Poli-Hidroxialcanoatos/análise , Espectrofotometria/métodos , Coloração e Rotulagem/métodos
18.
Health Sci Rep ; 1(12): e100, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30623054

RESUMO

BACKGROUND: In June 2014, the Argentinean Ministry of Health published guidelines for the management of neonates born at the limit of viability (≤25 weeks of gestation). We explored the opinion of neonatologists in Buenos Aires, Argentina, regarding the initiation of life-sustaining treatment (LST) in critically ill neonates, focusing on the effect of sociocultural factors on their opinion. METHODS: An anonymous survey was designed to explore the opinions of Argentinean neonatologists on whether or not to initiate LST in newborns born prematurely. Five hundred eighty neonatologists from 36 neonatal units were invited to participate, and 315 specialists from 34 neonatal units completed the survey (response rate 54%). The survey was conducted between June 2014 and February 2015. RESULTS: 9.5% (30/315) of the neonatologists answered they would begin LST on neonates born at 22 weeks, 42.5% (134/315) at 23 weeks, 37% (117/315) at 24 weeks, 7% (22/315) at 25 weeks, and 4% (12/315) at ≥26 weeks. Cumulatively then, 96% of participants stated they would start LST at 25 weeks of gestation or less. On multivariate analysis, a "transcendent" value of life and lack of consideration of the local legal framework for making medical decisions in the delivery room were statistically associated with an opinion in favor of initiation of LST in neonates born at the limit of viability. More than 50% of the Argentinean neonatologists surveyed answered they would initiate treatment at a gestational age of less than 23 weeks, despite the fact that the recommendations of the Argentinean Ministry of Health are to only give comfort care for these neonates. The opinion of most Argentinean neonatologists surveyed thus differs from that recommended by the guidelines of Argentina. CONCLUSION: The most frequent opinion of Argentinean neonatologists was to initiate LST in neonates at the limit of viability. Certain factors, in particular the sense of a transcendent meaning to life and lack of consideration of the local legal framework for making medical decisions in the delivery room, seem to influence the decision to start LST.

19.
Neurosci Lett ; 666: 17-23, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29248616

RESUMO

PURPOSE: Previously we showed that systemic administration of IMT504 prevents or ameliorates mechanical and thermal allodynia in rats with sciatic nerve crush. Here we analyzed if IMT504 is also effective in reducing mechanical allodynia and inflammation in rats undergoing hindpaw inflammation. MATERIALS AND METHODS: Male Sprague-Dawley rats received unilateral intraplantar injection of complete Freund́s adjuvant (CFA), and were grouped into: 1) untreated CFA, 2) vehicle-treated CFA, 3) IMT504-treated CFA (5 daily (5*) doses of 20, 2 or 0.2 mg/kg, or 3*2 mg/kg). Naïve groups were also included. Finally, early (immediately after intraplantar CFA) and late (7 days after intraplantar CFA) IMT504 treatment protocols were also tested. Hindpaw mechanical allodynia, dorsoventral thickness, edema and cellular infiltration of ipsilateral hindpaws were evaluated in all groups. RESULTS: Untreated CFA rats exhibited mechanical allodynia of quick onset (day 1) and long duration (7 weeks inclusive). Early and late treatments with 5*20 mg/kg IMT504 to CFA rats resulted in both quick and long-lasting antiallodynic effects, as compared to untreated CFA rats. This was also the case in CFA rats undergoing late IMT504 treatment at lower doses (3* and 5*2 mg/kg). Very low doses of IMT504 (5*0.2 mg/kg) only showed a mild improvement in withdrawal threshold, never reaching basal levels. Finally, rats treated with 3* or 5*2 mg/kg or 5*0.2 mg/kg exhibited significant decreases in dorsoventral thickness, edema, and inflammatory cell infiltration of the inflamed hindpaw. CONCLUSION: Early and late administration of IMT504 results in quick and long-lasting reductions in mechanical allodynia and hindpaw edema. While the mechanisms behind these effects remain to be established, data suggests that IMT504 administration could be a promising strategy in the control of inflammatory pain.


Assuntos
Comportamento Animal/efeitos dos fármacos , Hiperalgesia/fisiopatologia , Inflamação/tratamento farmacológico , Oligodesoxirribonucleotídeos/farmacologia , Animais , Doença Crônica , Modelos Animais de Doenças , Adjuvante de Freund , Hiperalgesia/induzido quimicamente , Inflamação/fisiopatologia , Masculino , Dor/tratamento farmacológico , Medição da Dor/métodos , Limiar da Dor/efeitos dos fármacos , Ratos Sprague-Dawley
20.
J Biotechnol ; 255: 28-32, 2017 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-28641986

RESUMO

Classical techniques employed to determine the amount of extractable poly(hydroxyalkanoate)s (PHAs) from cells, are laborious and destructive. Sudan black staining is commonly used in the laboratory to investigate the presence of intracellular PHA. The aim of the present study was to develop a low-cost alternative technique to achieve a quick determination of extractable intracellular PHA. This methodology employs a basic laboratory spectroscopy equipment and Sudan black dye for spectra determination. The correlation between the content of PHA in cell samples taken directly from the culture flask and its spectra was determined using partial least square regression analysis and simple linear regression analysis. The best fit obtained for calibration correlation analysis (R2=0.944, RSE: 1.24%), together with the good extractable PHA predictions (RSE=0.51%) demonstrate that the proposed methodology constitutes a fast way with high potential for the determination of extractable PHA. Based on its simplicity and flexibility, its application would be suitable in routine monitoring and rapid quantification in large-scale processes involving PHA metabolism.


Assuntos
Bacillus megaterium/crescimento & desenvolvimento , Poli-Hidroxialcanoatos/análise , Compostos Azo , Bacillus megaterium/metabolismo , Técnicas Bacteriológicas , Corantes , Análise dos Mínimos Quadrados , Naftalenos
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