Fisiopatologia da pressão intra-abdominal em animais de companhia

Dissertação de Mestrado Integrado em Medicina VeterináriaObjectivos do estudo: O aumento da pressão intra-abdominal (PIA) é um evento bem documentado em inúmeras condições clínicas em Medicina Humana (MH), estando este mal documentado em Medicina Veterinária. Este promove alterações fisiopatológicas adversas em vários sistemas orgânicos aumentando a morbilidade e a mortalidade (Joubert, 2006). O trabalho dividiu-se: 1.ª Fase - avaliação da aplicabilidade do método transvesical (MT) e determinação dos valores normais da PIA para felídeos e canídeos. Segundo o conhecimento do autor não existem valores descritos na literatura para felídeos, estando só descritos para canídeos (Drellich, 2000); 2.ª fase- Identificar afecções que levem à alteração da PIA provocando Síndrome de Compartimentalização Abdominal (SCA). Na sequência do trabalho foi estabelecida uma fórmula matemática que traduz as forças envolvidas no MT. Material e Métodos: Dos vários métodos disponíveis para a sua determinação, o MT constitui o Gold Standard e um dos mais facilmente aplicáveis em MH (Karnak, Bingol-kologlu, Karaagaoglu, Buyukpamukçu & Tanyel, 2001). Este consiste na colocação de uma algália associada a uma válvula de três vias conectada a uma coluna de água. Após remoção do conteúdo vesical e instilação de uma quantidade de fluido padrão permite-se o equilíbrio dinâmico entre ambos, determinando-se o valor da PIA em cm de H2O (Drellich, 2000). População controlo em estudo: 39 felídeos e 11 canídeos. Critério de inclusão: ausência de patologia comprovada por exame clínico e exames complementares. População em estudo: 12 felídeos e 21 canídeos. Critério de inclusão: evidência de afecção em pacientes cirúrgicos e não cirúrgicos que possa alterar a PIA. Resultados: População Controlo - PIA em felídeos foi de 4.63 cm H2O (intervalo:2.9-7.1cm H2O,DP±1.15). Em canídeos a PIA foi de 4.62 cm H2O (intervalo:3.23-8.05cm H2O,DP±1.43). População em estudo - PIA em felídeos com afecção foi de 7.3 cm H2O (intervalo:2.00-16.5cm H2O,DP±4.06). Em canídeos a PIA foi de 12.06 cm H2O (intervalo:3.20-26.5 cm H2O,DP±6.28). Discussão/Conclusão: O MT pode assim ser utilizado para determinar PIA em felídeos normais e os valores obtidos são similares aos descritos para humanos e canídeos (Drellich, 2000). Em todas as fases do estudo foram estabelecidos vários factores que afectam a mensuração da PIA, como a cirurgia, peso, sexo, entre outros. O MT pode ser traduzido matematicamente aumentado a sua fidedignidade. O único caso da SCA foi observado num canídeo do sexo feminino com insuficiência cardíaca.ABSTRACT - Objectives of the study: Increases in intra-abdominal pressure (IAP) can be associated to potentially harmful effects in several organ systems increasing the morbility and mortality of patients. (Joubert, 2006) IAP measurement is well documented in Human Medicine but not in Veterinary Medicine. This study was divided in two phases: the first was designed to test the applicability of transurethral method (TM) and to determine the normal values of IAP in healthy cats and dogs. In the author’s knowledge there are no reports of IAP TM measurement in cats (Drellich, 2000).The second phase consisted in the identification of condition that can increase IAP and cause Abdominal Compartment Syndrome (ACS). During the study a mathematic formula was developed to include all the forces that influence IAP measurement by TM. Materials and Methods: The determination of IAP through TM is considered the most accurate indirect method in Human Medicine (Karnak, Bingol-kologlu, Karaagaoglu, Buyukpamukçu & Tanyel, 2001). IAP measurement: a urinary catheter was connected to a water column by a three way stopcock. After collecting urine, a preset amount of sterile saline solution was introduced in the empty bladder. IAP volume was obtained when the point of equilibrium between the water column and the bladder was obtained (Drellich, 2000) and measured in cm de H2O. Control population in study: 39 cats and 11 dogs. Inclusion criteria: absence of disease verified by physical examination and additional diagnostic tests. Study population: 12 cats and 21 dogs. Inclusion criteria: presence of a pathological condition both in surgical and non surgical patients that could increase IAP. Results: Control Population - IAP for all cats was 4.63 cm H2O (range: 2.9-7.1cm H2O,SD±1.15). In dogs the IAP was 4.62 (range:3.23-8.05cm H2O,SD±1.43). Study Population: IAP for cats was 7.3 cm H2O (range:2.0-16.5cm H2O,SD±4.06). IAP for dogs was 12.06 cm H2O (range:3.20-26.5 cm H2O,SD±6.28). Discussion/Conclusions: TM seems to be suitable for assessing IAP in normal cats. Feline IAP values are similar to those described for humans and dogs (Drellich, 2000). Several factors influence TM measure including weight, sex of the patient, surgery and others. TM can be described by a mathematical formula providing a validation of the method. The only case of abdominal compartment syndrome was observed in a female dog with right heart failure

Impact of allergic rhinitis and specific subcutaneous immunotherapy on peripheral blood basophils of patients sensitized to Dermatophagoides pteronyssinus

BACKGROUND: Basophils are important effectors cells in allergic rhinitis (AR) since they are involved in immunoglobulin (Ig) E – mediated inflammation and in the release of pro-inflammatory mediators. Specific subcutaneous immunotherapy (SCIT) provides clear immunologic modulation in some immune cells, however its systemic effects on basophils are not well known. METHODS: Peripheral blood (PB) samples from 43 patients with allergic rhinitis mono-sensitized to Dermatophagoides pteronyssinus (Dpt) [33 of them under SCIT with allergoid Dpt extract, in maintenance dose (SCIT), with evaluation just before SCIT injection (SCIT-T0) and 4 hours later (SCIT-T4) and the other 10 Dpt allergic patients never having, in the past, undergone specific immunotherapy treatment (NSIT)], and 15 healthy age- and gender-matched controls (HG), were analyzed. For each sample, the total (t-IgE) and specific IgE (s-IgE) was performed, as well as, the relative frequency and absolute number of PB basophils and receptor-bound IgE and IgG expression were evaluated by flow cytometry and the Histamine N-methyltransferase (HNMT) and tryptase α/β1 (TPSAB1) gene expression was assessed by real-time PCR. RESULTS: Higher levels of receptor-bound IgE were observed in SCIT patients, which are correlated with the levels of serum t-IgE and s-IgE, whereas no significant differences were observed for receptor-bound IgG. Regarding HNMT mRNA expression, significantly lower expression levels were detected in AR patients compared to HG, independently of type of therapy. Moreover a negative correlation was found between HNMT gene expression and time under SCIT. Conversely, tryptase gene expression was significantly up-regulated in NSIT when compared to HG; however in SCIT patients, tryptase gene expression was significantly decreased than in NSIT patients. No differences were found for any parameter between SCIT-T0 and SCIT-T4 with exception of a transient increased expression of tryptase in SCIT-T4. CONCLUSION: PB basophils from patients with AR show altered functional features, which seems to be influenced by SCIT, suggesting that these cells could be useful to clarify the SCIT triggered mechanisms at a systemic level

Biomechanical Basis of Bone Fracture and Fracture Osteosynthesis in Small Animals

The mastery of concepts related to biomechanics in bone fracture is crucial for the surgical success of osteosynthesis. The understanding of the basics of bone fracture is a skill fundamental to the choice of the correct method of osteosynthesis. Deep knowledge of implants, namely, their mechanic characteristics, and the correct technical use following the recommended guidelines for each type are crucial factors to decrease surgical failure and complications rate. This chapter reviews the biomechanical parameters of fracture repair that influence construct stiffness and strength. The authors also provided practical examples of the biomechanics concepts applied in clinical practice during this chapter. Metal alloys used in orthopedic implants are also fundamentally reviewed in their physical properties during this chapter. Fracture patterns vary hugely among patients and contributed to the difficult understanding of forces acting in fracture lines. However, fracture biomechanics basic knowledge and how osteosynthesis methods counteract the forces acting on fractures are key to surgical success

Prototype of an affordable pressure-controlled emergency mechanical ventilator for COVID-19

We present a viable prototype of a simple mechanical ventilator intended as a last resort to ventilate COVID-19 patients. The prototype implements the pressure-controlled continuous mandatory ventilation mode (PC-CMV) with settable breathing rates, inspiration/expiration time ratios and FiO2 modulation. Although safe, the design aims to minimize the use of technical components and those used are common in industry, so its construction may be possible in times of logistical shortage or disruption or in areas with reduced access to technical materials and at a moderate cost, affordable to lower income countries. Most of the device can be manufactured by modest technical means and construction plans are provided.Comment: This version differs from version 2 in that it includes toxicological and bio-safety tests and updated electronic

Low frequency of TERT promoter mutations in gastrointestinal stromal tumors (GISTs).

Somatic mutations in the promoter region of telomerase reverse transcriptase (TERT) gene, mainly at positions c. − 124 and c. − 146 bp, are frequent in several human cancers; yet its presence in gastrointestinal stromal tumor (GIST) has not been reported to date. Herein, we searched for the presence and clinicopathological association of TERT promoter mutations in genomic DNA from 130 bona fide GISTs. We found TERT promoter mutations in 3.8% (5/130) of GISTs. The c. − 124C4T mutation was the most common event, present in 2.3% (3/130), and the c. − 146C4T mutation in 1.5% (2/130) of GISTs. No significant association was observed between TERT promoter mutation and patient’s clinicopathological features. The present study establishes the low frequency (4%) of TERT promoter mutations in GISTs. Further studies are required to confirm our findings and to elucidate the hypothetical biological and clinical impact of TERT promoter mutation in GIST pathogenesis.This project was partially supported by Barretos Cancer Hospital internal research funds (PAIP) and CNPq Universal Grant (476192/2013-7) to RMR. NCC is a recipient of an FAPESP Doctoral Fellowship (2013/25787-3). Further funding from the project ‘Microenvironment, metabolism and cancer’ that was partially supported by Programa Operacional Regional do Norte (ON.2—O Novo Norte) under the Quadro de Referência Estratégico Nacional (QREN) and the Fundo Europeu de Desenvolvimento Regional (FEDER). IPATIMUP is an Associate Laboratory of the Portuguese Ministry of Science, Technology and Higher Education that is partially supported by the FCT

Interactions lake-atmosphere: The ALEX 2014 field campaign and numerical simulations

The ALqueva hydro-meteorological EXperiment, ALEX 2014, was an integrated field campaign with measurements of chemical, physical and biological parameters in water and air at different experimental sites in the region of the Alqueva reservoir, a 250 km2 man made lake, in the southeast of Portugal. The Field campaign took place from June 1 to September 30, 2014 and comprises an Intensive Observation Period (IOP) of three days (22 to 24 July). During the four months, the over water fluxes of momentum, heat and mass (H2O and CO2) were obtained with an integrated Open-Path CO2 /H2O Gas Analyser and 3D Sonic Anemometer, mounted on a floating platform, where radiative fluxes were also measured, as well as the water temperature profile. Eight near surface weather stations were operating in the area and air quality, atmospheric electrical field (Potential Gradient) and radon (222Rn) concentration were continuous monitored. Along this period, in situ measurements, water samples and biological elements were monthly collected from three fixed platforms placed in the lacustrine zone and from selected sites in the margins. During the IOP, radiosondes were launched every tree hours, allowing a characterization of the atmospheric boundary layer and its evolution. In 10 occasions Geigersondes were coupled to the radiosondes in order to obtain the atmospheric ionization profile. The boundary layer was characterized with a Ceilometer and the vertical distribution of O3 and NO2 were obtained from a Spectrometer. A GPS network of 15 GNSS stations was installed in order to map the water vapour. The sky brightnesson the nights of July 24 and 25, was measured using a Sky Quality Meter. The lake-atmosphere interactions and its impact in the boundary layer structure and in the local circulations are studied using data collected during the ALEX 2014 POI together with results from numerical simulations performed with the non-hydrostatic Meso-NH french model

Kinematic Analysis Comparison between Normal and Cranial Cruciate Ligament Rupture Canine Gait Analysis: An Exploratory Study

This study aims to apply a kinematic analysis to characterize and compare a normal canine gait with a canine gait with cranial cruciate ligament (CrRL) rupture with free and open-source software. Two dogs walked ten times. A bidimensional kinematic analysis was performed. Spatiotemporal analysis showed significant differences between dogs. The dog with CrCL rupture obtained higher results for all parameters except stance and step time. Also, the stifle angle did not verify differences in absolute angle, but the signal showed differences in patterns between normal and abnormal gait. This study supports that software assisting clinicians’ diagnosis with CrCl ruptures

Non-Invasive System for Measuring Intra-Abdominal Pressure

Extended Abstract Purpose: Monitoring surgical and intensive care patients is an usual procedure in hospital units Methods: The selection of the features was realized according with the literature review of the parameters that can be influenced by IAP Results The IAP showed average results of 4.05 ± 3.60 mmHg and the parameters with the highest statistical correlation with the IAP were: weight (cc0.48), ACSA (cc0.46), perimeter (cc0.34), diastolic (cc0.25) and mean blood pressure (cc0.17), duration of the QRS (cc0.20) and the amplitude of the R wave (cc0.12). Systems based on the 18 inputs were constructed and a simplified system was created only with the inputs with the highest correlation with the output. The best ANN created was built with 7 inputs, with the activation function Tansig and the training function Bayseian regularization. This network showed results of linear regression coefficient of 0.97. The ANFIS that demonstrated the best results was also constructed with the simplified model, with only 7 entries. The best results were obtained with Sugeno inference system and 20 rules demonstrating an error of 2.10 (training), 1.73 (test) and 3.79 (validation). Conclusion: This type of non-invasive methodology allows the determination of IAP continuously. The ANN and the ANFIS created allowed predicting IAP with low error compared to real values. This type of methodology can be used in human medicine

Sera from patients with active systemic lupus erythematosus patients enhance the toll-like receptor 4 response in monocyte subsets

Background: Systemic Lupus Erythematosus (SLE) is an auto-immune disease whose complex pathogenesis remains unraveled. Here we aim to explore the inflammatory ability of SLE patients\u27 sera upon peripheral blood (PB) monocyte subsets and myeloid dendritic cells (mDCs) obtained from healthy donors. Methods: In this study we included 11 SLE patients with active disease (ASLE), 11 with inactive disease (ISLE) and 10 healthy controls (HC). PB from healthy donors was stimulated with patients\u27 sera, toll-like receptor (TLR) 4 ligand - lipopolysaccharide or both. The intracellular production of TNF-α was evaluated in classical, non-classical monocytes and mDCs, using flow cytometry. TNF-α mRNA expression was assessed in all these purified cells, after sera treatment. Results: We found that sera of SLE patients did not change spontaneous TNF-α production by monocytes or dendritic cells. However, upon stimulation of TLR4, the presence of sera from ASLE patients, but not ISLE, significantly increased the intracellular expression of TNF-α in classical and non-classical monocytes. This ability was related to titers anti-double stranded DNA antibodies in the serum. High levels of anti-TNF-α in the patients\u27 sera were associated with increased TNF-α expression by co-cultured mDCs. No relationship was found with the levels of a wide variety of other pro-inflammatory cytokines. A slight increase of TNF-α mRNA expression was observed in these purified cells when they were cultured only in the presence of SLE serum. Conclusions: Our data suggest that SLE sera induce an abnormal in vitro TLR4 response in classical and non-classical monocytes, reflected by a higher TNF-α intracellular expression. These effects may be operative in the pathogenesis of SLE

Loss of RKIP expression is associated with poor survival in GISTs

Gastrointestinal stromal tumours (GISTs) are rare mesenchymal tumours of the digestive tract and are commonly driven by oncogenic mutations in KIT and PDGFRA genes. Tumour size, location, mitotic index and KIT/PDGFRA mutations are the most important prognostic parameters in GISTs. However, additional studies screening for new molecular prognostic markers in GISTs are missing. Raf kinase inhibitor protein (RKIP) has been considered as a suppressor of metastasis and a prognostic marker in several neoplasms. In the present study we aimed to examine whether RKIP expression is associated with GIST clinical-pathological features. Using immunohistochemistry, we determined RKIP expression levels in a well-characterised series of 70 GISTs. We found that RKIP is expressed in the great majority of cases, and absent in approximately 9% of GISTs. Additionally, we found that loss of RKIP expression was not due to the promoter methylation as assessed by methylation-specific PCR. Loss of RKIP expression was associated with poor disease-specific survival and with tumour necrosis in GISTs. Furthermore, a statistical tendency was observed between the positive RKIP expression and absence of metastasis. So far, this is the first study assessing RKIP expression levels in GISTs. We conclude that loss of RKIP expression could have an important role as prognostic marker in GISTs.OM is recipient of a PhD fellowship (SFRH/BD/36463/2007) from FCT, Portugal. This study was partially supported by NOVARTIS Oncology, Portugal