The new Ribopeaks (RPK-II): Updated and enlarged tool for bacterial classification based on r-protein m/z data.

Ribopeaks is a rapid, sensitive, and economic web tool for bacterial identification based on m/z data from MALDI-TOF MS. To provide greater accuracy and robustness in the Ribopeaks analyzes we present an updated bacterial identification tool version, called Ribopeaks II (RPK-II). RPK-II contains a larger database, with r-protein data from fully sequenced bacterial genomes and optimized algorithms. Furthermore, this new version provides additional information about the identified bacterium, regarding antibiotic resistance.

Effects of vaccine registration on disease prophylaxis: a systematic review.

BACKGROUND: The impact of the pandemic caused by the coronavirus (SARS-CoV-2), causing the disease COVID-19, has brought losses to the world in terms of deaths, economic and health problems. The expected return of the public to activities adapted to the new health situation led to discussions about the use of vaccination and its effects. However, the demand for proof of vaccination showed how inconsistent, unregistered, and uncontrolled this health process is with current technologies. Despite the proven effectiveness of vaccines in reducing infection rates, mortality, and morbidity, there are still doubts about their use in preventing certain infections and injuries, as well as the use of digital medical records for identification at public events and disease prevention. Therefore, this review aims to analyze the use of digital immunization cards in disease prevention in general. METHODS: A systematic review of Science, PubMed/MEDLINE, LILACS /BSV, CINALH, and IEEE and Xplore was performed using PRISMA guidelines. The authors summarized the studies conducted over the last decade on the impacts of prophylaxis by control through immunization cards. Studies were selected using the following terms: Vaccination; Mobile Applications; Health Smarts Cards; Immunization Programs; Vaccination Coverage. For data analysis, we used Mendeley, Excel, RStudio, and Bibliometrix software among others. RESULTS: A total of 1828 publications were found. After applying eligibility criteria (Articles published in Portuguese, Spanish or English in the last 10 years). Studies that only dealt with paper or physical records were excluded, as well as studies that were not linked to their country's health Department, as a possibility of bias exists with these types of information). After removing duplicates and applying filters 1 and 2, we included 18 studies in this review. This resulted in 18 papers that met our priori inclusion criteria; it was found that the most relevant sources were from the databases of the Institute of Electrical and Electronics Engineers (IEEE). CONCLUSIONS: Considering the selected studies, we found that scientific evidence and epidemiological surveillance are essential tools to characterize the efficiency and effectiveness of immunization passport protection intervention and to ethically justify them. Technological development of digital vaccine passports can assist in vaccination programs and positively impact disease prophylaxis.

The Role of Pain Inflexibility and Acceptance among Headache and Temporomandibular Disorders Patients.

Temporomandibular disorders (TMD) and headache are complex. This study aims to assess the association between TMD, headache, and psychological dimensions such as psychological inflexibility and pain acceptance. The sample consisted of 120 participants following a non-probabilistic convenience sampling strategy through a direct invitation to the patients attending our facilities and their relatives (n = 61 diagnosed with headache, n = 34 diagnosed with TMD-headache, n = 25 control group). Diagnostic Criteria for Temporomandibular Disorders (DC-TMD), International Classification of Headache Disorders (ICHD-3 beta version), Chronic Pain Acceptance Questionnaire (CPAQ-8), and Psychological Inflexibility in Pain Scale (PIPS) were used as assessment tools. One-way ANOVA, multiple regression analysis (MRA), and the Johnson-Neyman approach were run by IBM SPSS, version 27 (IBM® Company, Chicago, IL, USA). The significance level was 0.05. One third of our sample presented with headache with TMD. Females were predominant. Males with headache, no systemic disease, less pain severity but higher frequency, living longer with the disease and having sensitive changes, showed higher pain acceptance. When headache occurs with TMD, women with higher education, no headache family history, less pain, and no motor changes showed higher pain acceptance. Patients with both conditions are more liable to have chronic pain and pain inflexibility. Pain intensity and willingness explain 50% of the psychological inflexibility in the headache group. In our sample, individuals suffering from both conditions show greater pain inflexibility, implicating more vivid suffering experiences, leading to altered daily decisions and actions. However, further studies are needed to highlight this possible association.

Influence of psoriasis lesions' location and severity on psychosocial disability and psychopathology. Observational study and psychometric validation of the SAPASI Portuguese version.

OBJECTIVES: The psychosocial impact of psoriasis is well documented. However, the contributing role of clinical disease characteristics is not satisfactorily explored. This study aimed to validate the Self-administered Psoriasis Area and Severity Index (SAPASI) to a Portuguese population (SAPASI-PT) and to perform its cross-validation, assessing how the results will generalize to an independent data set, with the Psoriasis Area and Severity Index (PASI), in order to assess the influence of psoriasis' severity on psychosocial disability and psychopathology. METHODS: A cross-sectional study with 228 patients with psoriasis was carried out. Data was collected through a sociodemographic and clinical questionnaire, SAPASI-PT, the Psoriasis Disability Index (PDI) and the Brief Symptoms Inventory (BSI). The cultural and linguistic adaptation of SAPASI to a Portuguese version and the cross validation with PASI was carried out. Multiple associations between psychosocial disability, psychopathology and severity, discomfort and location of lesions were investigated through logistic regression models. RESULTS: A good adjustment model for SAPASI-PT is found. Also, associations between psychosocial disability, psychopathology and the psoriasis severity and discomfort are found. The existence of lesions is positively associated with the severity of the disease. Patients with lesions in hands or genitals are those reporting a greater discomfort. The presence of lesions in hands is positively associated with PDI, i.e., with leisure and with treatment, marginally. Additionally, patients scoring higher in the personal dimension are found to have a significantly greater percentage of lesions in the genitals. CONCLUSIONS: The psoriasis severity and location of lesions are important determinants of patients´ quality of life. Lesions on face, hands and genitals are associated with a higher impact on psychosocial wellbeing of patients. Psychological counselling should be considered within psoriasis treatment context in patients with the described disease manifestations.

Randomized Controlled Trial: Cognitive-Narrative Therapy for IPV Victims.

The objective is to test the efficacy of cognitive-narrative therapy in the treatment of depression, post-traumatic stress disorder (PTSD), complex posttraumatic stress disorder (CPTSD) and borderline symptoms on a sample of women who suffered from intimate partner violence (IPV). Trial design is a longitudinal randomized controlled trial with a sample of 19 battered women allocated in two groups, a control group and treatment group, assessed twice at baseline before intervention, and at follow-up. The outcome measures were the Patient Health Questionnaire, International Trauma Questionnaire, PTSD and CPTSD Diagnostic Interview Schedule for International Classification of Diseases (ICD)-11, Conjugal Violence Exposure Scale (CVES), Life Events Checklist and Intervention Program Satisfaction Assessment Instrument. The treatment group received a four-session cognitive-narrative manualized intervention. There were no statistically significant differences between groups at baseline and follow-up, however, positive effect sizes ranging between 0.04 and 0.43 were found in depression, PTSD, and borderline, as well in some CPTSD dimensions when analyzing baseline-follow-up deltas between groups. There was also a negative effect size of -0.28 in the CPTSD total. This intervention is effective in the treatment of depression, PTSD and borderline and is an important tool in the treatment of these disorders.

Temperature-dependence on the optical properties of chitosan carbon dots in the solid state.

We report the synthesis of chitosan-derived aminated carbon dots with dual fluorescence bands and their influence on the morphology, absorption and emission spectral profiles as well as on the band gap energy in relation to thermal treatment after synthesis. To unravel these changes, we performed spectroscopic measurements in the solid state on two stages at temperatures ranging from 303 to 453 K. For the first heating stage, the emission spectrum showed a 20 nm red shift and a new absorption band at 350 nm, possibly related to new bonds and/or nitrogenous molecular fractions. For the second heating stage in the same temperature range, no displacements in the emission spectrum were observed and both the energy gap and bandwidths for the two emission bands are practically constant, indicating a change nitrogen moiety exposed on the surface. Furthermore, through atomic force microscopy it was noted that the morphology and size of the CDs were not significantly affected by the increase in temperature. It is noteworthy that the values of the Huang-Rhys factor, respectively, 2.584 × 10-10 and 2.315 × 10-9 for band I and II emission after the second heating indicate a mechanism of weak electron-phonon interactions. This work may open a novel perspective for the development of new surface modulation strategies for carbon dots subjected to thermal treatment in the solid state.

Photobiomodulation: systematic review and meta-analysis of the most used parameters in the resolution diabetic foot ulcers.

The most common photobiomodulation parameters used to aid in the treatment of diabetic foot ulcers were investigated in this paper. The databases MEDLINE, LILACS, MEDCARIB, PAHO-IRIS, and WHOLIS were searched with the following descriptors: diabetic foot ulcers AND low-level laser therapy OR low-level therapy AND wound healing; this search was conducted from January of 2014 to December of 2019. Inclusion criteria were randomized clinical trials on humans. Exclusion criteria were systematic reviews, literature reviews, studies with animals, studies lacking photobiomodulation parameters, and studies with non-diabetic individuals. The Jadad scale was used in order to analyze the methodological quality of the matching papers. There were seventeen studies found on PubMed and four on LILACS. Among these, seven were selected, according to the inclusion and exclusion criteria. Two out of the seven matching studies obtained a high score, and five obtained a low score, on the Jadad scale. The studies settled on the use of 600-nm and 800-nm wavelength spectrum. Most of the analyzed papers on photobiomodulation on diabetic foot ulcers did not describe the detailed parameters in their methodology. None of the studies featured the maximum score with regard to the Jadad scale for methodological quality. The relations of energy versus wavelength and power versus wavelength were divergent among the parameters on the papers. Therefore, it is necessary to analyze the parameters for an optimized power value in order to improve the results of the treatment.

Effects of photobiomodulation therapy in the integration of skin graft in rats.

Skin graft is one of the most common techniques used in plastic surgery and repair. However, there are some complications that can lead to loss of the skin graft. Thus, several features have been studied with the aim of promoting the integration of skin grafts. Among these resources, the use of laser photobiomodulation (laser PBM) has been highlighted. The present study aimed to investigate the effects of laser PBM on the viability and integration of skin grafts in rats. Twenty male Wistar rats (± 250 g) were randomly assigned into two experimental groups with 10 animals each: control group, animals submitted to skin graft and simulation of laser PBM; laser PBM group, submitted to the skin graft and submitted to laser PBM at 660 nm, 40 mW, 60 s, 2.4 J. The animals were submitted to laser photobiomodulation immediately after the surgical procedure and each 24 h. Animal euthanasia occurred on the 7th day after surgery, 24 h after the last treatment session. The histopathological analysis revealed that the laser PBM showed better adhesion of the graft when compared to the control group. Likewise, the morphometric analysis of mast cells, blood vessels, and collagen showed a statistically significant increase in the animals irradiated with the laser PBM when compared to the control group. In addition, immunohistochemical analysis demonstrated that the laser PBM showed statistically higher immunoexpression of FGF when compared to the CG. However, IL-4 immunoexpression did not show statistical difference between the experimental groups. From the results obtained in the present study, it can be suggested that laser photobiomodulation was effective in promoting the integration and viability of total skin grafts in rats.

Comparative study on laser and LED influence on tissue repair and improvement of neuropathic symptoms during the treatment of diabetic ulcers.

To compare the influence of laser and LED on tissue repair and neuropathic symptoms during treatment of diabetic foot. An intervention survey conducted in a health center located in Brazil, contemplating ten sessions, twice a week, with randomization in two groups. In one group, the wounds were treated with GaAlAs laser, with a wavelength of 830 nm, 30 mW, and power density 0.84 W/cm2, the other group by LED 850 nm, 48 mW, and power density 1.05 W/cm2. For the analysis of wound size, photographic records analyzed by the ImageJ® software were used, and the neuropathy evaluation card examined. With regard to the laser group, a reduction in wound extension of 79.43% was observed at the end of the 10th session; the patients in the LED group had a 55.84% decrease in the healing process; comparing the two therapies was observed a better healing in the participants of the laser group, with 81.17%, in relation to the LED after the end of the sessions; regarding the evaluation of the neuropathic condition, there was a significant improvement in both therapies. There was improvement of the neuropathic signs and symptoms, also improvement of the tissue repair in the two therapeutic modalities; however, the laser presented a higher rate of speed in relation to the LED.

Mitochondrial dynamics (fission and fusion) and collagen production in a rat model of diabetic wound healing treated by photobiomodulation: comparison of 904 nm laser and 850 nm light-emitting diode (LED).

OBJECTIVE: Mitochondrial dysfunction has been associated with the development of diabetes mellitus which is characterized by disorders of collagen production and impaired wound healing. This study analyzed the effects of photobiomodulation (PBM) mediated by laser and light-emitting diode (LED) on the production and organization of collagen fibers in an excisional wound in an animal model of diabetes, and the correlation with inflammation and mitochondrial dynamics. METHODS: Twenty Wistar rats were randomized into 4 groups of 5 animals. Groups: (SHAM) a control non-diabetic wounded group with no treatment; (DC) a diabetic wounded group with no treatment; (DLASER) a diabetic wounded group irradiated by 904 nm pulsed laser (40 mW, 9500 Hz, 1 min, 2.4 J); (DLED) a diabetic wounded group irradiated by continuous wave LED 850 nm (48 mW, 22 s, 1.0 J). Diabetes was induced by injection with streptozotocin (70 mg/kg). PBM was carried out daily for 5 days followed by sacrifice and tissue removal. RESULTS: Collagen fibers in diabetic wounded skin were increased by DLASER but not by DLED. Both groups showed increased blood vessels by atomic force microscopy. Vascular endothelial growth factor (VEGF) was higher and cyclooxygenase (COX2) was lower in the DLED group. Mitochondrial fusion was higher and mitochondrial fusion was lower in DLED compared to DLASER. CONCLUSION: Differences observed between DLASER and DLED may be due to the pulsed laser and CW LED, and to the higher dose of laser. Regulation of mitochondrial homeostasis may be an important mechanism for PBM effects in diabetes.

Ribopeaks: a web tool for bacterial classification through m/z data from ribosomal proteins.

Summary: MALDI-TOF MS is a rapid, sensitive and economic tool for bacterial identification. Highly abundant bacterial proteins are detected by this technique, including ribosomal proteins (r-protein), and the generated mass spectra are compared with a MALDI-TOF MS spectra database. Currently, it allows mainly the classification of clinical bacteria due to the limited number of environmental bacteria included in the spectra database. We present a wide-ranging bacterium classifier tool, called Ribopeaks, which was created based on r-protein data from the Genbank. The Ribopeaks database has more than 28 500 bacterial taxonomic records. It compares the incoming m/z data from MALDI-TOF MS analysis with models stored in the Ribopeaks database created by machine learning and then taxonomically classifies the bacteria. Availability and implementation: The software is available at http://www.ribopeaks.com. Supplementary information: Supplementary data are available at Bioinformatics online.

Light-emitting diode modulates carbohydrate metabolism by pancreatic duct regeneration.

Pancreatic lesions can produce metabolic disorders. Light-emitting diode (LED) has been used as a safe and effective phototherapy for cell proliferation and regeneration. We investigate the effects of phototherapy using LED irradiation on the pancreas after the injection of streptozotocin (STZ) to induce experimental diabetes and evaluate that the ß cells can regenerate in the pancreas in an in vivo model and observe its implications on the control of carbohydrate metabolism. Twenty Wistar rats were randomized into three groups: non-diabetic control, diabetic control, and diabetic treated with LED. Except for the non-diabetic control group, all were induced to diabetes type I by streptozotocin injection. Treated groups were irradiated by LED: λ = 805 nm; 40 mW, 22 s; spot diameter 5 mm, spot area 0.196 cm2, 0.88 J that it was applied on pancreas projection area for 5 consecutive days and monitored for 30 days. Diabetic group treated with LED showed regeneration of islets and ducts (p = 0.001) on the pancreas. Intraperitoneal insulin tolerance test showed differences between the diabetic control and diabetic treated groups (p = 0.03). In diabetic control group, the hepatic glycogen content was 296% lower when compared with diabetic treated with LED. Furthermore, in the diabetic control group, the glycogen content of the gastrocnemius muscle was 706% smaller when compared with diabetic treated with LED. This study shows that LED was able to modify morphological and metabolic features and also altered carbohydrate metabolism on irradiated pancreas in experimental model of diabetes.

Randomized Controlled Trial of a Cognitive Narrative Crisis Intervention for Bereavement in Primary Healthcare.

BACKGROUND AND AIMS: As there are known risks of retraumatization through bereavement crisis interventions, we tailored a new intervention lowering the degree of direct emotional activation. However, we need some evidence on the effects of depression and psychotraumatic symptoms between 1 and 6 months after a loss. METHOD: We conducted a randomized controlled trial with two groups: control group (n = 18) and experimental group (n = 11) in two assessments (1 and 6 months after loss); both included a semi-structured interview (Socio-Demographic Questionnaire, Beck Depression Inventory and the Impact of Events Scale-Revised-IES-R). The experimental group had a cognitive-narrative program with four sessions: recalling; cognitive and emotional subjectivization; metaphorization; and projecting sessions. RESULTS: Participants in the experimental and control groups have lower levels of depression and traumatic stress 6 months after a loss. Statistically significant results in emotional numbing IES-R sub-scale are observed. CONCLUSIONS: A brief narrative-based cost-effective intervention has a positive effect on depression, controlling the traumatic stress and time after a loss.

Low-level laser therapy (904nm) can increase collagen and reduce oxidative and nitrosative stress in diabetic wounded mouse skin.

BACKGROUND AND OBJECTIVE: Over the last decade we have seen an increased interest in the use of Low-Level Laser Therapy (LLLT) in diseases that involve increased oxidative stress. It is well established that hyperglycemia in diabetes elicits a rise in reactive oxygen species (ROS) production but the effect of LLLT remains unclear. This study aimed to investigate whether LLLT was able to improve oxidative/nitrosative stress parameters in the wound healing process in diabetic mice. STUDY DESIGN/MATERIALS AND METHODS: Twenty male mice were divided into four groups: non-irradiated control (NIC), irradiated control (IC), non-irradiated and diabetic (NID), irradiated and diabetic (ID). Diabetes was induced by administration of streptozotocin. Wounds were created 120days after the induction of diabetes in groups IC and ID and these groups were irradiated daily for 5days (superpulsed 904nm laser, average power 40mW, 60s). All animals were sacrificed 1day after the last irradiation and histology, collagen amount, catalase activity, nitrite and thiobarbituric acid reactive substances (TBARS) were measured. RESULTS: Histology showed that collagen fibers were more organized in IC and ID when compared to NID group, and significant differences in collagen content were found in group ID versus NID. Catalase activity was higher in IC group compared to other groups (p<0.001). TBARS levels were higher in IC versus NIC, but were lower in ID versus NID (p<0.001). Nitrite was lower in both irradiated groups versus the respective non-irradiated groups (p<0.001). CONCLUSIONS: Delayed wound healing in diabetes is still a challenge in clinical practice with high social costs. The increased production of collagen and decreased oxidative and nitrosative stress suggests that LLLT may be a viable therapeutic alternative in diabetic wound healing.

Alterações do equilíbrio escapular em escolares de 10 a 12 anos no município de Parnaíba/PI / Changes in the scapular balance of 10 to 12 years old children at Parnaíba/PI

Crianças adaptam-se rapidamente a uma nova postura e, se esteposicionamento for inadequado, pode acarretar em comprometimentoscorporais, prejudicando sua postura. Os padrões posturaisassumidos na infância progressivamente podem formar a posturado adulto. São inúmeras as variáveis que influenciam a ergonomiacorporal, dentre elas estão os distúrbios no equilíbrio escapular.Este estudo objetivou analisar quantitativamente as alteraçõesescapulares em escolares no município de Parnaíba/PI. Trata-se deum estudo transversal, onde foi realizada uma avaliação posturalem 148 crianças entre 10 e 12 anos de ambos os sexos. O testeutilizado na análise da verificação da variação de frequências e dograu de associação entre as variáveis foi o Qui-Quadrado. O nívelde significância estabelecido foi o equivalente a p < 0,05. O presenteestudo observou as seguintes alterações no equilíbrio estáticoda cintura escapular: (5,2%) protusão, (16,5%) adução, (20,6%)abdução, (27,8%) elevação. A taxa de normalidade foi 29,9%. Aalteração escapular mais comum nos alunos avaliados foi a elevaçãoescapular com 27,8%. Concluiu-se que 66,2% dos escolaresavaliados apresentaram alterações do alinhamento escapular e aocompararmos as outras alterações, há variação significativamentedistinta na prevalência da adução e protusão escapular...

Children adapt quickly to a new position but, if this position isinadequate, can lead to physical impairments, affecting definitivelythe posture. The postural patterns in childhood can gradually modifythe adult posture. There are numerous variables that influence thebody posture, among which are disturbances in the scapular balance.This study aimed to quantitatively analyze the changes in scapularbalance in children at Parnaíba/PI. It was a cross-sectional study onpostural evaluation in 148 children of both genders, 10 to 12 yearsold. The tests used in the analysis of verification of frequency rangesand the degree of association between variables were chi-square. Thesignificance level was equivalent to p < 0.05. The present study observedthe following changes in static balance of the shoulder girdle:(5.2%) protrusion, (16.5%) adduction, (20.6%) abduction (27.8%)increase. The rate of normality was 29.9%. The most commonchange in scapular balance students was elevation with 27.8%. It wasconcluded that 66.2% of schoolchildren present scapular alignmentchanges and, comparing to other changes, they present a significantprevalence of scapular adduction and protrusion...

Application of the laser radiation in patients of pressure ulcers: clinical and histomorphometric analysis of the derm

In this work, we analyze the clinical alterations and histological modifications in patients with not infect ulcers of pressure, submitted to the Laser irradiation GaAs (wavelength 904 nm, doses 3 J/cm², during 1 minute and prompt application) during 5 days consecutive and as a group radiated during 15 days alternating. In the clinical evaluation after the laser irradiation observed presence of exudation, granulation tissue and points of bleed after the third day of irradiation. The computerized morph quantitative analysis demonstrated that submitted to the laser irradiation during the 15 days busy area for the 4115,922 vases was of µm², and in the radiated ones during 5 4348,253 days of µm², both in a 0,25 area of cm² of derma. The gotten results suggest that this therapeutically one was efficient as to assist in the processes of tissue regeneration in the patients treated in the research.

Neste trabalho, analisamos as alterações clínicas e modificações histológicas em pacientes com úlceras de pressão não infectadas, submetidos à irradiação Laser AsGa (comprimento de onda 904 nm, dose 3 J/cm², durante 1 minuto e aplicação pontual) durante 5 dias consecutivos e um segundo grupo irradiado durante 15 dias alternados. Na avaliação clínica após a irradiação laser observou-se presença de exsudação, tecido de granulação e pontos de sangramento após o terceiro dia de irradiação. A análise morfológica e quantitativa computadorizada demonstrou que os submetidos à irradiação laser durante 15 dias a área ocupada pelos vasos foi de 4115922 µm², e nos irradiados durante 5 dias de 4348253 µm², ambos em uma área de 0,25 cm² de derme. Os resultados obtidos sugerem que esta terapêutica foi eficaz como auxiliar nos processos de regeneração tecidual nos pacientes tratados na pesquisa.

Avaliação toxicológica do óleo essencial de Piper aduncum L. / Toxicological evaluation of the essential oil of Piper aduncum L.

Este trabalho teve como objetivo a avaliação da toxidade aguda e subaguda do óleo essencial de Piper aduncum pela determinação da DL50 em camundongos e a análise dos parâmetros bioquímicos e hematológicos em ratos. A planta é utilizada na medicina popular da região amazônica em diversas doenças e no seu óleo essencial o constituinte majoritário é o fenilpropanóide dilapiol, com propriedades inseticida, fungicida, bactericida, larvicida e moluscicida. A DL50 foi de 2,400 ± 191,7 mg/kg. O óleo essencial não alterou de maneira significativa os parâmetros hematológicos e bioquímicos em relação ao controle no tratamento subagudo, exceto a redução da creatinina. O valor da DL50 e os resultados observados nos parâmetros hematológicos e bioquímicos sugerem que o óleo essencial apresenta toxidade baixa.

The aim of this work was the acute and subacute toxicological evaluation of the essential oil of Piper aduncum with the determination of the LD50 in mice and the analysis of their hematological and biochemical parameters in rats. The plant is used in the Amazon folk medicine for several diseases and the phenylpropanoid dilapiolle is the main constituent of its essential oil, possessing insecticidal, fungicidal, bactericidal, larvicidal and molluscicidal properties. The LD50 was 2.400 ± 191.7 mg/kg. The essential oil did not change the hematological and biochemical parameters in a significant manner when compared with the control in the subacute treatment, excepting the reduction of creatinine. The LD50 and the hematological and biochemical results have suggested that the essential oil presents low toxicity.

Blockade of leukotriene B4 prevents articular incapacitation in rat zymosan-induced arthritis.

We investigated whether leukotrienes mediate cell influx and articular incapacitation in zymosan-induced arthritis. Rats received 1 mg zymosan intra-articularly (i.a.). The hyperalgesia was measured using the rat articular incapacitation test. Cell influx, leukotriene B(4) and prostaglandin E(2) levels were assessed in the joint exudate, at 6 h. Groups received either the leukotriene B(4) synthesis inhibitor MK 886 (3-[1-(4-chlorobenzyl)-3-t-butyl-thio-5-isopropylindol-2-yl)]-2,2-dimethylpropanoic acid 30 min before or 2 h after the zymosan; 0.3-3 mg kg(-1) i.p.), the leukotrienes synthesis inhibitor BWA(4)C (N-(3-phenoxycinnamyl)-acetohydroxamic acid--2 h after the zymosan; 10 microg i.a.) or the peptido-leukotrienes antagonist sodium montelukast (30 min before and 2 h after the zymosan; 10 mg kg(-1) per os). MK 886 inhibited the articular incapacitation and cell influx, while reducing leukotriene B(4), but not prostaglandin E(2) levels. BWA(4)C inhibited the articular incapacitation. Sodium montelukast did not affect either of the parameters. The data suggest that leukotriene B(4) is involved in cell influx and articular incapacitation in zymosan arthritis.