Characterization of a monoclonal antibody recognizing mast cells

Immunohistochemical screening for monoclonal antibodies prepared by immunization of mice with a rat osteoblastic cell population led to identification of one antibody that reacted against a small population of cells present in the soft connective tissue compartment of 21 days fetal rat calvaria. The morphology of the cells and the immunohistochemical staining characteristics (a distinct intracellular granular pattern) suggested that the antibody might be reacting specifically against mast cells. We used combined histochemistry and immunohistochemistry to further characterize this antibody, designated RCJ102. Cryosections containing calvaria bone, soft connective tissues and skin were prepared from the top of the head of 21 days fetal rats, and from adult rats cryosections of lung, muscle, adipose tissue and small intestine were prepared. Some sections were labelled by indirect immunofluorescence with RCJ102; corresponding sections were labelled histochemically with toluidine blue. There was a direct correspondence between mast cells identified histochemically and cells labelling with RCJ102 in all tissues except intestine, in which the mast cell detectable by histochemistry were not labelled by RCJ102. These results suggest that the RCJ102 antibody will be a valuable new reagent for further elucidation of the heterogeneity described between connective tissue and intestinal mucosal mast cells.

Atuação fisioterapêutica na lesão medular em unidade de terapia intensiva: Atualização de literatura

Objective. Collate and update knowledge in relation to physical therapy in spinal cord injury (SCI) in the intensive care unit (ICU). Method. We performed a literature update in the databases Lilacs, PubMed and Scielo, crossing the descriptors spinal cord injury, cinesiotherapy, physiotherapy, mobilization, rehabilitation, intensive care unit, respiratory therapy and electrotherapy in the period of 2005 to 2010. Results. We found 21 studies, however, only five articles met the inclusion criteria. Kinesiotherapy is essential since the phase of spinal shock, since it favors the maintenance of joint range of motion and flexibility, and to prevent circulatory complications caused/ resulted from prolonged immobilization in bed. Respiratory therapy promotes bronchial hygiene, correction of abnormal respiratory patterns and respiratory diseases. The electrotherapy is a feature still little used by physiotherapists in the intensive care units. Conclusions. The physical therapy in SCI in ICU is focused on motor rehabilitation through kinesiotherapy and intervention through the respiratory bronchial hygiene and training of respiratory muscles. New treatment modalities such as electrotherapy, there have been in intensive environment, there is a need for more studies to confirm benefits and risks of this feature in the spinal cord.

Estudo do músculo diafragma em ratos com insuficiência cardíaca crônica: composição das miosinas e expressão dos fatores de regulação miogênica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da qualidade de vida, força muscular respiratória e distância percorrida no teste de caminhada de seis minutos em pacientes com hipertensão arterial pulmonar sob tratamento farmacológico específico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Benefits of kinesiotherapy and aquatic rehabilitation on sickle cell anemia. A case report

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Analgesia controlada pelo paciente comparada a analgesia padrão na função pulmonar, força muscular respiratória e dor no pós-operatório e revascularização do miocárdio: ensaio clínico randonizado

Pós-graduação em Bases Gerais da Cirurgia - FMB

Estudo do Padrão Respiratório e Movimento Toracoabdominal em Valvopatia Mitral

FUNDAMENTO: pacientes com valvopatia mitral podem evoluir com congestão pulmonar, que aumenta o trabalho dos músculos respiratórios; essa sobrecarga pode alterar o padrão respiratório com predomínio do deslocamento torácico ou presença de movimentos paradoxais. OBJETIVO: a) estudar o padrão respiratório e movimento toracoabdominal (MTA) em pacientes com doença mitral b) estudar o efeito do posicionamento nos parâmetros respiratórios c) correlacionar hipertensão pulmonar com presença de incoordenação do MTA. MÉTODOS: o padrão respiratório e o MTA de pacientes com doença mitral foram avaliados por pletismografia respiratória por indutância, nas posições dorsal e sentada, durante dois minutos de respiração tranquila. Analisou-se volume corrente (Vc) e tempos respiratórios e as variáveis do MTA. RESULTADOS: de 65 pacientes incluídos, 10 foram retirados, 29 participaram do grupo estenose mitral e 26 do grupo insuficiência mitral. O Vc, a ventilação pulmonar e o fluxo inspiratório médio aumentaram significantemente na posição sentada, sem diferenças entre os grupos. O MTA manteve-se coordenado entre os grupos e as posições; no entanto, cinco pacientes na posição dorsal apresentaram incoordenação (três no grupo estenose mitral; dois no grupo insuficiência mitral) com correlação significante com valores de pressão de artéria pulmonar (r = 0,992, p = 0,007). CONCLUSÃO: o padrão respiratório e o MTA não apresentam diferenças entre pacientes com estenose ou insuficiência mitral. A posição sentada aumenta o Vc sem alterar os tempos respiratórios. A presença de incoordenação toracoabdominal na posição dorsal esteve associação à hipertensão pulmonar.

Identification of adequate neurally adjusted ventilatory assist (NAVA) during systematic increases in the NAVA level

Neurally adjusted ventilatory assist (NAVA) delivers airway pressure (P(aw)) in proportion to the electrical activity of the diaphragm (EAdi) using an adjustable proportionality constant (NAVA level, cm·H(2)O/μV). During systematic increases in the NAVA level, feedback-controlled down-regulation of the EAdi results in a characteristic two-phased response in P(aw) and tidal volume (Vt). The transition from the 1st to the 2nd response phase allows identification of adequate unloading of the respiratory muscles with NAVA (NAVA(AL)). We aimed to develop and validate a mathematical algorithm to identify NAVA(AL). P(aw), Vt, and EAdi were recorded while systematically increasing the NAVA level in 19 adult patients. In a multistep approach, inspiratory P(aw) peaks were first identified by dividing the EAdi into inspiratory portions using Gaussian mixture modeling. Two polynomials were then fitted onto the curves of both P(aw) peaks and Vt. The beginning of the P(aw) and Vt plateaus, and thus NAVA(AL), was identified at the minimum of squared polynomial derivative and polynomial fitting errors. A graphical user interface was developed in the Matlab computing environment. Median NAVA(AL) visually estimated by 18 independent physicians was 2.7 (range 0.4 to 5.8) cm·H(2)O/μV and identified by our model was 2.6 (range 0.6 to 5.0) cm·H(2)O/μV. NAVA(AL) identified by our model was below the range of visually estimated NAVA(AL) in two instances and was above in one instance. We conclude that our model identifies NAVA(AL) in most instances with acceptable accuracy for application in clinical routine and research.

Non-invasive neurally adjusted ventilatory assist in rabbits with acute lung injury

OBJECTIVE: Neurally adjusted ventilatory assist uses the electrical activity of the diaphragm (EAdi)-a pneumatically-independent signal-to control the timing and pressure of the ventilation delivered, and should not be affected by leaks. The aim of this study was to evaluate whether NAVA can deliver assist in synchrony and proportionally to EAdi after extubation, with a leaky non-invasive interface. DESIGN AND SETTING: Prospective, controlled experimental study in an animal laboratory. ANIMALS: Ten rabbits, anesthetized, mechanically ventilated. INTERVENTIONS: Following lung injury, the following was performed in sequential order: (1) NAVA delivered via oral endotracheal tube with PEEP; (2) same as (1) without PEEP; (3) non-invasive NAVA at unchanged NAVA level and no PEEP via a single nasal prong; (4) no assist; (5) non-invasive NAVA at progressively increasing NAVA levels. MEASUREMENTS AND RESULTS: EAdi, esophageal pressure, blood gases and hemodynamics were measured during each condition. For the same NAVA level, the mean delivered pressure above PEEP increased from 3.9[Symbol: see text]+/-[Symbol: see text]1.4[Symbol: see text]cmH(2)O (intubated) to 7.5[Symbol: see text]+/-[Symbol: see text]3.8[Symbol: see text]cmH(2)O (non-invasive) (p[Symbol: see text]<[Symbol: see text]0.05) because of increased EAdi. No changes were observed in PaO(2) and PaCO(2). Increasing the NAVA level fourfold during non-invasive NAVA restored EAdi and esophageal pressure swings to pre-extubation levels. Triggering (106[Symbol: see text]+/-[Symbol: see text]20[Symbol: see text]ms) and cycling-off delays (40[Symbol: see text]+/-[Symbol: see text]21[Symbol: see text]ms) during intubation were minimal and not worsened by the leak (95[Symbol: see text]+/-[Symbol: see text]13[Symbol: see text]ms and 33[Symbol: see text]+/-[Symbol: see text]9[Symbol: see text]ms, respectively). CONCLUSION: NAVA can be effective in delivering non-invasive ventilation even when the interface with the patient is excessively leaky, and can unload the respiratory muscles while maintaining synchrony with the subject's demand.

Titration and implementation of neurally adjusted ventilatory assist in critically ill patients

BACKGROUND: Neurally adjusted ventilatory assist (NAVA) delivers assist in proportion to the patient's respiratory drive as reflected by the diaphragm electrical activity (EAdi). We examined to what extent NAVA can unload inspiratory muscles, and whether unloading is sustainable when implementing a NAVA level identified as adequate (NAVAal) during a titration procedure. METHODS: Fifteen adult, critically ill patients with a Pao(2)/fraction of inspired oxygen (Fio(2)) ratio < 300 mm Hg were studied. NAVAal was identified based on the change from a steep increase to a less steep increase in airway pressure (Paw) and tidal volume (Vt) in response to systematically increasing the NAVA level from low (NAVAlow) to high (NAVAhigh). NAVAal was implemented for 3 h. RESULTS: At NAVAal, the median esophageal pressure time product (PTPes) and EAdi values were reduced by 47% of NAVAlow (quartiles, 16 to 69% of NAVAlow) and 18% of NAVAlow (quartiles, 15 to 26% of NAVAlow), respectively. At NAVAhigh, PTPes and EAdi values were reduced by 74% of NAVAlow (quartiles, 56 to 86% of NAVAlow) and 36% of NAVAlow (quartiles, 21 to 51% of NAVAlow; p < or = 0.005 for all). Parameters during 3 h on NAVAal were not different from parameters during titration at NAVAal, and were as follows: Vt, 5.9 mL/kg predicted body weight (PBW) [quartiles, 5.4 to 7.2 mL/kg PBW]; respiratory rate (RR), 29 breaths/min (quartiles, 22 to 33 breaths/min); mean inspiratory Paw, 16 cm H(2)O (quartiles, 13 to 20 cm H(2)O); PTPes, 45% of NAVAlow (quartiles, 28 to 57% of NAVAlow); and EAdi, 76% of NAVAlow (quartiles, 63 to 89% of NAVAlow). Pao(2)/Fio(2) ratio, Paco(2), and cardiac performance during NAVAal were unchanged, while Paw and Vt were lower, and RR was higher when compared to conventional ventilation before implementing NAVAal. CONCLUSIONS: Systematically increasing the NAVA level reduces respiratory drive, unloads respiratory muscles, and offers a method to determine an assist level that results in sustained unloading, low Vt, and stable cardiopulmonary function when implemented for 3 h.

Avaliação da musculatura inspiratória e expiratória na doença pulmonar obstrutiva crônica leve e grave comparada aos indivíduos saudáveis

Introdução: A DPOC é uma doença respiratória prevenível e tratável, caracterizada por limitação persistente ao fluxo aéreo, hiperinsuflação e aprisionamento aéreo. A dispneia e a intolerância aos esforços, decorrentes destas alterações fisiopatológicas sofre influência de vários fatores. Dentre estes, o recrutamento e a sobrecarga imposta aos músculos inspiratórios e expiratórios são de fundamental importância, porém a participação destes ainda não foi completamente elucidada em diferentes gravidades da doença. Objetivos: O objetivo principal deste estudo foi avaliar a mecânica ventilatória, e o grau de recrutamento da musculatura inspiratória e expiratória na DPOC leve e grave, na condição de repouso e durante um teste máximo de exercício, comparado a um grupo de indivíduos saudáveis. Metodologia: Trata-se de um estudo transversal envolvendo 36 indivíduos, sendo 24 pacientes portadores de DPOC e 12 voluntários sadios. As avaliações foram divididas em 2 visitas. No D1, foram realizadas uma avaliação clínica, avaliação de dispneia (mMRC) e de qualidade de vida (SGRQ), além da prova de função pulmonar completa. Na 2ª visita, realizada com intervalo de 1 semana, foram avaliadas: as pressões respiratórias máximas estáticas por meio de métodos volitivos (PImax, PEmax, SNIP, Pes sniff, Pga sniff e Pdi sniff) e não volitivos (Twitch cervical bilateral e T10); avaliação da sincronia toracoabdominal por pletismografia de indutância; avaliação do recrutamento dos músculos inspiratórios e expiratórios ao repouso pela eletromiografia de superfície; e, posteriormente, um teste de exercício cardiopulmonar incremental para estudo de todas essas variáveis no esforço. Resultados: Foram avaliados 24 pacientes (12 leves e 12 graves) e 12 indivíduos saudáveis da mesma faixa etária. A maioria dos pacientes apresentava comprometimento significativo da qualidade de vida e os pacientes do grupo grave eram mais sintomáticos. A função pulmonar encontrava-se alterada na maioria dos pacientes. Destes, 79,2% apresentavam aprisionamento aéreo e 70,8% tinham redução da DLCO. Tais alterações foram semelhantes nos 2 grupos de pacientes. A força muscular estática medida por métodos volitivos e não volitivos estava reduzida nos 2 grupos e mostrou relação com o VEF1. No exercício, a dispneia foi o principal motivo para interrupção do teste em 70% dos pacientes. A HD esteve presente em 87,5% dos pacientes. O comportamento das pressões respiratórias foi significativamente diferente entre os 3 grupos. Os pacientes com DPOC apresentaram maior atividade diafragmática (Pdi) comparado aos controles e a participação da musculatura expiratória também foi maior neste grupo, principalmente nos graves. Apesar disso, os pacientes com DPOC apresentaram uma eficiência mecânica reduzida, ou seja, esse incremento da força muscular foi insuficiente para manter uma ventilação adequada para uma determinada carga. Com o aumento da demanda ventilatória, houve recrutamento precoce e progressivo dos músculos inspiratórios e expiratórios durante o exercício. O trabalho resistivo e o expiratório foram significativamente diferentes entre os controles e os pacientes com DPOC desde o início do exercício. Como consequência destas alterações, a intensidade da dispneia durante o TECP foi maior nos pacientes com DPOC (leve e grave) para a mesma carga e mesma ventilação-minuto (VE), quando comparada aos indivíduos do grupo-controle. Conclusões: O conjunto destes achados demonstra que o comprometimento dos músculos inspiratórios e expiratórios contribuiu significativamente para a dispneia e a intolerância ao exercício tanto no DPOC leve quanto no DPOC grave. E que este comprometimento pode não ser detectado com os testes máximos de força ao repouso

Loss of skeletal muscle in cancer: biochemical mechanisms

Patients with cancer often undergo a specific loss of skeletal muscle mass, while the visceral protein reserves are preserved. This condition known as cachexia reduces the quality of life and eventually results in death through erosion of the respiratory muscles. Nutritional supplementation or appetite stimulants are unable to restore the loss of lean body mass, since protein catabolism is increased mainly as a result of the activation of the ATP-ubiquitin-dependent proteolytic pathway. Several mediators have been proposed. An enhanced protein degradation is seen in skeletal muscle of mice administered tumour necrosis factor (TNF), which appears to be mediated by oxidative stress. There is some evidence that this may be a direct effect and is associated with an increase in total cellular-ubiquitin-conjugated muscle proteins. Another cytokine, interleukin-6 (IL-6), may play a role in muscle wasting in certain animal tumours, possibly through both lysosomal (cathepsin) and non-lysosomal (proteasome) pathways. A tumour product, proteolysis-inducing factor (PIF) is produced by cachexia-inducing murine and human tumours and initiates muscle protein degradation directly through activation of the proteasome pathway. The action of PIF is blocked by eicosapentaenoic acid (EPA), which has been shown to attenuate the development of cachexia in pancreatic cancer patients. When combined with nutritional supplementation EPA leads to accumulation of lean body mass and prolongs survival. Further knowledge on the biochemical mechanisms of muscle protein catabolism will aid the development of effective therapy for cachexia.

Normalização de eletromiografia de superfície dos músculos respiratórios em sujeitos saudáveis: contração voluntária máxima máxima isométrica versus pressões respiratórias máximas

Aim : To evaluate and to standardize surface electromyography (sEMG) normalization procedures for respiratory muscles by comparing muscle activation during Maximal Voluntary Isometric Contraction (MVIC) and Maximal Respiratory Pressures (MIP, MEP and sniff test). Methods: Healthy subjects were evalua ted regarding demographics, spirometry and sEMG during the five maneuvers: sniff test, MIP , MEP and Maximal Voluntary Isometric C ontraction (MVIC) of RA, SCM and SC A . For electrode placement, skin was prepared with abrasion, followed by shaving in the foll owing regions for acquisition of el ectromyographic signals: (1) SC M: lower third of the distance between the mastoid process and t he sternoclavicular joint; (2) SC A : 5 cm to the right from the sternoclavicular joint and at this point, up to 2 cm; and (3 ) RA: the level of umbilicus, 4 cm to the right. In electromyographic variables analysis , the data normality was assessed by Shapiro - Wilk test. Comparisons among studied maneuvers were performed by Friedman Test and Dunn’s post - hoc for multiple comparisons a mong inspiratory maneuvers, and Mann Whitney test for expiratory maneuvers. Subgroups differences between genders were performed by Student's t test or Mann - Whitney test according to data normality. Results: 35 subjects participated in the study, b ut 5 we re excluded (BMI> 25 kg/ m²). Sample consisted of 30 subjects (1 5 women), mean age 27.3±7.43 years, BMI 22.2 ± 1.69 kg/m² and spirometric indices within normal limits. Specific MVIC for SCM, SCA and RA showed the highest RMS. When we grouped sample into gender we found no difference among RMS values for the studied SCM maneuvers, while for SCA, MVIC SCM / SCA was the one with the highest RMS and for RA, MVIC RA in men. Once considering women, MVIC SCM/SCA showed the highest RMS for SCM, SCA and MVIC RA showed t he highest value for RA. Conclusion: MVIC for SCM, SCA and RA muscles showed the highest RMS values. When comparing RMS between the studied groups, there was no significant difference between men and women.

Effects of gestational and postnatal exposure to chronic intermittent hypoxia on diaphragm muscle contractile function in the rat

Alterations to the supply of oxygen during early life presents a profound stressor to physiological systems with aberrant remodeling that is often long-lasting. Chronic intermittent hypoxia (CIH) is a feature of apnea of prematurity, chronic lung disease, and sleep apnea. CIH affects respiratory control but there is a dearth of information concerning the effects of CIH on respiratory muscles, including the diaphragm—the major pump muscle of breathing. We investigated the effects of exposure to gestational CIH (gCIH) and postnatal CIH (pCIH) on diaphragm muscle function in male and female rats. CIH consisted of exposure in environmental chambers to 90 s of hypoxia reaching 5% O2 at nadir, once every 5 min, 8 h a day. Exposure to gCIH started within 24 h of identification of a copulation plug and continued until day 20 of gestation; animals were studied on postnatal day 22 or 42. For pCIH, pups were born in normoxia and within 24 h of delivery were exposed with dams to CIH for 3 weeks; animals were studied on postnatal day 22 or 42. Sham groups were exposed to normoxia in parallel. Following gas exposures, diaphragm muscle contractile, and endurance properties were examined ex vivo. Neither gCIH nor pCIH exposure had effects on diaphragm muscle force-generating capacity or endurance in either sex. Similarly, early life exposure to CIH did not affect muscle tolerance of severe hypoxic stress determined ex vivo. The findings contrast with our recent observation of upper airway dilator muscle weakness following exposure to pCIH. Thus, the present study suggests a relative resilience to hypoxic stress in diaphragm muscle. Co-ordinated activity of thoracic pump and upper airway dilator muscles is required for optimal control of upper airway caliber. A mismatch in the force-generating capacity of the complementary muscle groups could have adverse consequences for the control of airway patency and respiratory homeostasis.

Chronic sustained hypoxia-induced redox remodeling causes contractile dysfunction in mouse sternohyoid muscle

Chronic sustained hypoxia (CH) induces structural and functional adaptations in respiratory muscles of animal models, however the underlying molecular mechanisms are unclear. This study explores the putative role of CH-induced redox remodeling in a translational mouse model, with a focus on the sternohyoid—a representative upper airway dilator muscle involved in the control of pharyngeal airway caliber. We hypothesized that exposure to CH induces redox disturbance in mouse sternohyoid muscle in a time-dependent manner affecting metabolic capacity and contractile performance. C57Bl6/J mice were exposed to normoxia or normobaric CH (FiO2 = 0.1) for 1, 3, or 6 weeks. A second cohort of animals was exposed to CH for 6 weeks with and without antioxidant supplementation (tempol or N-acetyl cysteine in the drinking water). Following CH exposure, we performed 2D redox proteomics with mass spectrometry, metabolic enzyme activity assays, and cell-signaling assays. Additionally, we assessed isotonic contractile and endurance properties ex vivo. Temporal changes in protein oxidation and glycolytic enzyme activities were observed. Redox modulation of sternohyoid muscle proteins key to contraction, metabolism and cellular homeostasis was identified. There was no change in redox-sensitive proteasome activity or HIF-1α content, but CH decreased phospho-JNK content independent of antioxidant supplementation. CH was detrimental to sternohyoid force- and power-generating capacity and this was prevented by chronic antioxidant supplementation. We conclude that CH causes upper airway dilator muscle dysfunction due to redox modulation of proteins key to function and homeostasis. Such changes could serve to further disrupt respiratory homeostasis in diseases characterized by CH such as chronic obstructive pulmonary disease. Antioxidants may have potential use as an adjunctive therapy in hypoxic respiratory disease.