Tecnologías disruptivas para la obtención de órganos y tejido artificial / Disruptive technologies for obtaining artificial organs and tissues / Tecnologias disruptivas para a obtenção de órgãos e tecidos artificiais

Propósito/Contexto. Este artículo tiene como objetivo exponer el panorama de las tecnologías disruptivas en la medicina regenerativa y la solución que plantean para la obtención de órganos y tejidos artificiales. En la actualidad, los métodos existentes, como los trasplantes y xenotrasplantes, han demostrado ser poco efectivos para solventar esa problemática de salud pública mundial. Metodología/Enfoque. Se hace una revisión de tecnologías como la ingeniería de tejidos, la ingeniería genética, la nanomedicina y la nanotecnología, que buscan sustituir o mejorar los métodos actuales. Resultados/Hallazgos. Las tecnologías disruptivas plantean aspectos bioéticos que deben ser vistos desde otra perspectiva; la manipulación de la materia a escala atómica y molecular abren un sinnúmero de posibilidades para mejorar la calidad de vida del hombre e incluso, prolongarla. Surge el concepto de nanobioética, en el que se toman los principios de la bioética contemporánea y se proyectan a escalas nanométricas para analizar las implicaciones positivas y negativas de la vida en esas dimensiones. Discusión/Conclusiones/Contribuciones. Los avances y tecnologías disruptivas plantean un impacto en la atención sanitaria, cambios socioculturales y nuevos paradigmas que implican desafíos desde lo científico, lo técnico y lo bioético.

Purpose/Context. The article aims to provide an overview of disruptive technologies in regenerative medicine as a solution to obtaining artificial organs and tissues. Existing methods such as transplants and xenotransplants have proven to be ineffective in resolving this world public health problem. Method/Approach. Technologies such as tissue engineering, genetic engineering, nanomedicine, and nanotechnology are addressed, which seek to replace or improve current methods. Results/Findings. Disruptive technologies involve bioethical aspects that must be considered from another perspective. The manipulation of matter on atomic and molecular scales opens up countless possibilities for improving the quality of human life and even extending it. As a result, the concept of nanobioethics has emerged, which takes the principles of contemporary bioethics and projects them on nanometric scales to analyze the positive and negative implications for life in these dimensions. Discussion/Conclusions/Contributions. Advances and disruptive technologies impact health care, produce sociocultural changes, and give rise to new paradigms, posing scientific, technical, and bioethical challenges.

Objetivo/Contexto. O presente artigo tem como objetivo expor o panorama respeito das tecnologias disruptivas na medicina regenerativa, e a solução que propõem para a obtenção de órgãos e tecidos artificiais. Atualmente os métodos existentes, como os transplantes e xenotransplantes, provaram ser pouco eficaz para resolver um problema de saúde pública mundial. Metodologia/Abordagem. Nesse sentido, é feita uma revisão de tecnologias como a engenharia de tecidos, a engenharia genética, a nanomedicina e a nanotecnologia, que buscam substituir ou melhorar os métodos atuais. Resultados/Descobertas. As tecnologias disruptivas colocam aspectos bioéticos que devem ser vistos sob outra perspectiva, a manipulação da matéria em escala atômica e molecular abrem inúmeras possibilidades para melhorar a qualidade de vida do homem e até prolongá-la. Surge então o conceito de nanobioética, no qual se tomam os princípios da bioética contemporânea, projetam-se em escalas nanométricas, buscando analisar as implicações positivas e negativas da vida nessas dimensões. Discussão/Conclusões/Contribuições. Os avanços e as tecnologias disruptivas causam impacto nos cuidados de saúde, mudanças socioculturais e novos paradigmas que implicam desafios nos aspectos científico, técnico e bioético.

Integrated 3D bioprinting-based geometry-control strategy for fabricating corneal substitutes / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

BACKGROUND@#The shortage of donor corneas is a severe global issue, and hence the development of corneal alternatives is imperative and urgent. Although attempts to produce artificial cornea substitutes by tissue engineering have made some positive progress, many problems remain that hamper their clinical application worldwide. For example, the curvature of tissue-engineered cornea substitutes cannot be designed to fit the bulbus oculi of patients.@*OBJECTIVE@#To overcome these limitations, in this paper, we present a novel integrated three-dimensional (3D) bioprinting-based cornea substitute fabrication strategy to realize design, customized fabrication, and evaluation of multi-layer hollow structures with complicated surfaces.@*METHODS@#The key rationale for this method is to combine digital light processing (DLP) and extrusion bioprinting into an integrated 3D cornea bioprinting system. A designable and personalized corneal substitute was designed based on mathematical modelling and a computer tomography scan of a natural cornea. The printed corneal substitute was evaluated based on biomechanical analysis, weight, structural integrity, and fit.@*RESULTS@#The results revealed that the fabrication of high water content and highly transparent curved films with geometric features designed according to the natural human cornea can be achieved using a rapid, simple, and low-cost manufacturing process with a high repetition rate and quality.@*CONCLUSIONS@#This study demonstrated the feasibility of customized design, analysis, and fabrication of a corneal substitute. The programmability of this method opens up the possibility of producing substitutes for other cornea-like shell structures with different scale and geometry features, such as the glomerulus, atrium, and oophoron.

Anterior segment optical coherence tomography findings in type I Boston keratoprosthesis / Achados de tomografia de coerência óptica do seguimento anterior em ceratoprótese de Boston tipo I

ABSTRACT Purpose: To report the results of high-resolution anterior segment optical coherence tomography of patients implanted with a type 1 Boston keratoprosthesis (KPro). Methods: The retrospective study cohort included 11 eyes of 11 patients (average age, 58.4 years; range, 34-83 years). All subjects underwent anterior segment optical coherence tomography at a single posteoperative time point. The main outcome measures were retro-backplate and retro-optic membrane formation, thinning and gap formation of the corneal carrier graft (melting), and degree of angle closure. Results: Preoperative diagnoses included chemical burn (55%), failed corneal transplant (36%), and Stevens-Johnson syndrome (9%). The mean postoperative follow-up duration was 38.5 (range, 12-72) months. The most frequent findings of anterior segment optical coherence tomography were retroprosthetic membrane formation (63%, 7/11), thinning of the corneal carrier graft (melting; 55%, 6/11), and a narrow or closed angle (91%, 10/11). Other less common findings were epithelial growth over the optic surface and periprosthetic cyst formation. Retroprosthetic membrane formation was observed in all patients with melting (6/11). Conclusions: Detailed postoperative examination and visualization of subtle changes of keratoprosthesis implanted eyes by slit lamp biomicroscopy are often difficult. Anterior segment optical coherence tomography is a useful, noninvasive, and quantitative imaging technique that provides useful information to postoperatively monitor the anatomic stability of an implanted keratoprosthesis.

RESUMO Objetivos: Reportar os resultados das imagens de pacientes com Ceratoprótese de Boston tipo I (KPro) usando tomografia de coerência óptica de alta resolução do seguimento anterior (AS-OCT). Métodos: Nós realizamos um estudo retrospectivo de pacientes submetidos à KPro. Um total de 11 olhos de 11 pacientes foram incluídos. As imagens de AS-OCT foram realizadas em um único tempo de pós-operatório. Os principais resultados incluem formação de membrana retroprostética atrás do prato posterior e atrás do cilindro ótico, afinamento e lacunas na córnea doadora (melt) e graus de ângulo fechado. Resultados: Os diagnósticos pré-operatórios inclui queimadura química (55%), falência pós transplante de córnea (36%) e síndrome de Stevens Johnson (9%). A idade média foi de 58.4 anos (escala, 34-83 anos). A média de tempo de pós-operatório foi de 38.5 meses (escala, 12-72 meses). Os achados mais frequentes de AS-OCT foram: membrana retroprostética, 63% (7/11); afinamento da córnea doadora (melting), 55% (6/11); angulo estreito ou fechado, 91% (10/11). Outros achados menos comuns foram crescimento epitelial sobre a superfície ótica e cistos periprostéticos. Todos os pacientes com melting (6/11) apresentaram membrana retroprostética. Conclusões: O exame pós-operatório e a visualização detalhada das mudanças em olhos com KPro pela lâmpada de fenda pode ser difícil. AS-OCT é uma técnica de imagem útil, não invasiva e quantitativa que permite o monitoramento da estabilidade anatômica no seguimento de KPro implantadas.

Bacterial cellulose and bacterial cellulose/polycaprolactone composite as tissue substitutes in rabbits' cornea / Celulose bacteriana e composto de celulose bacteriana/policaprolactone para substituto tissular na córnea de coelho

In order to test the performance of bacterial cellulose/polycaprolactone composite (BC/PCL) and pure bacterial cellulose (BC) as tissue substitutes in rabbits' cornea, a superficial ulcer containing 5mm in diameter and 0.2mm deep was made in the right cornea of 36 rabbits, then a interlayer pocket was created from the basis of this ulcer. Twelve rabbits received BC/PCL membrane and 12 were treated with BC membranes, both membranes with 8mm in diameter. The remaining rabbits received no membrane constituting the control group. The animals were clinically followed up for 45 days. Three animals of each group were euthanized at three, seven, 21, and 45 days after implantation for histological examination of the cornea along with the implant. Clinical observation revealed signs of moderate inflammatory process, decreasing from day 20th in the implanted groups. Histology showed absence of epithelium on the membranes, fibroplasia close to the implants, lymph inflammatory infiltrate with giant cells, collagen disorganization, with a predominance of immature collagen fibers in both groups with implants. Although inflammatory response is acceptable, the membranes used does not satisfactorily played the role of tissue substitute for the cornea during the study period.(AU)

Com objetivo de testar o desempenho do compósito celulose bacteriana/policaprolactona (CB/PCL) e da celulose bacteriana pura (CB) como substitutos teciduais em córnea de coelhos, foi realizada uma úlcera superficial de 5 mm de diâmetro e 0,2 mm de profundidade na córnea direita de 36 coelhos, criando-se um bolso interlamelar a partir da base dessa úlcera. Doze animais receberam a membrana do compósito CB/PCL e 12 foram tratados com membranas de CB, ambas com 8 mm de diâmetro, os coelhos restantes não receberam nenhuma membrana, constituindo o grupo controle. Os animais foram acompanhados clinicamente até 45 dias. Três animais de cada grupo sofreram eutanásia aos três, sete, 21 e 45 dias após o implante das membranas para análise histológica da córnea juntamente com o implante. À observação clínica, houve sinais de processo inflamatório moderado, diminuindo a partir do 20º dia nos grupos implantados. A histologia demonstrou ausência de epitélio sobre as membranas, fibroplasia próxima aos implantes, infiltrado inflamatório linfo-histiocitário com células gigantes, desorganização do colágeno, com predominância de fibras imaturas de colágeno em ambos os grupos com implantes. Embora a resposta inflamatória seja aceitável, as membranas utilizadas não desempenharam satisfatoriamente o papel de substituto tecidual para a córnea, no período estudado.(AU)

Síntese e caracterização de derivados de hemoglobina para aplicação terapêutica / Synthesis and characterization of hemoglobin based oxygen carriers for therapeutic application

A transfusão de sangue é uma intervenção terapêutica capaz de salvar muitas vidas. Entretanto, transfusões também apresentam uma alta gama de possíveis eventos adversos, questões logísticas, econômicas e sociais. Dentre as principais preocupações terapêuticas estão a incompatibilidade (principalmente do sistema ABO), a transmissão de microrganismos patogênicos, os distúrbios imunomodulatórios, as reações hemolíticas, o aumento estatístico do risco de morte proporcional ao volume de sangue infundido, dentre outros. Diversas alternativas às transfusões sanguíneas são propostas na literatura científica, dentre elas o desenvolvimento de transportadores de oxigênio que utilizam a hemoglobina, comumente intitulados substitutos sanguíneos. Neste âmbito, o presente estudo teve como objetivo o desenvolvimento de uma rota de síntese e a síntese de partículas de gelatina contendo hemoglobina polimerizada. Para tanto, realizou-se a síntese do polietileno glicol bis-[succinimidil succinato], extraiu-se e polimerizou-se com glutaraldeído ou polietileno glicol bis-[succinimidil succinato] hemoglobina de sangue bovino e, partículas de gelatina coriácea ou óssea contendo hemoglobina polimerizada foram sintetizadas e caracterizadas. A síntese do polietileno glicol bis-[succinimidil succinato] (SSPEG) foi caracterizada por espectroscopia RAMAN, análise diferencial de calorimetria (DSC) e os resultados obtidos indicaram o sucesso das reações. O produto da reação de polimerização da hemoglobina e albumina com o SSPEG foi verificado por SDS-PAGE e os resultados obtidos indicaram a formação com sucesso de polímeros de alta massa molecular. As partículas contendo hemoglobina polimerizada geradas com gelatina coriácea apresentaram diâmetro hidrodinâmico de 1370 nm, dispersividade de 0,029 e potencial zeta de -36,1 mV. As partículas contendo hemoglobina polimerizada geradas com gelatina óssea apresentaram diâmetro hidrodinâmico de 438 nm, dispersividade de 0,563 e potencial zeta de -24,5 mV. Os resultados obtidos sugerem a aplicabilidade da gelatina coriácea para a produção de partículas contendo hemoglobina polimerizada com possível aplicação como transportador de oxigênio

Blood transfusion is a therapeutic intervention that can save many lives. However, transfusion is also related to several possible adverse therapeutic events and logistic, economic and social concerns. Among the major therapeutic concerns are incompatibility (mainly of the ABO group system), pathogenic microorganisms' transmission, immunomodulatory disturbances, hemolytic reactions, death risk increase that is proportional to the infused volume, among others. Several alternatives to blood transfusion are proposed in the scientific literature. Among them is the development of hemoglobin based oxygen carriers, commonly entitle blood substitutes. To this extent, the present work aimed to develop a synthetic route and to synthesize gelatin particles containing polymerized hemoglobin. To this purpose PEG bis(succinimidyl succinate) was synthesized, bovine hemoglobin was extracted and polymerized with glutaraldehyde or PEG and polyhemoglobin contained particles of gelatin from leather or bones were synthesized and characterized. PEG bis(succinimidyl succinate) synthesis was characterized by RAMAN spectroscopy and by differential scanning calorimetry (DSC) and the obtained results indicated the successful synthesis. The reaction product of the polymerization of hemoglobin or albumin with PEG was verified by SDS-PAGE and the results indicated the successful formation of high molecular mass polymers. The particles generated with leather gelatin and polyhemoglobin had a hydrodynamic diameter of 1370 nm, dispersity of 0.029 and zeta potential of -36.1 mV. Particles generated with bone gelatin and polyhemoglobin had hydrodynamic diameter of 438 nm, dispersity of 0.563 and zeta potential of -24.5 mV. The obtained results suggest the applicability of leather gelatin for the production of polyhemoglobin containing particles aiming to the development of a hemoglobin based oxygen carrier

Toward angiogenesis of implanted bio-artificial liver using scaffolds with type I collagen and adipose tissue-derived stem cells

BACKGROUNDS/AIMS: Stem cell therapies for liver disease are being studied by many researchers worldwide, but scientific evidence to demonstrate the endocrinologic effects of implanted cells is insufficient, and it is unknown whether implanted cells can function as liver cells. Achieving angiogenesis, arguably the most important characteristic of the liver, is known to be quite difficult, and no practical attempts have been made to achieve this outcome. We carried out this study to observe the possibility of angiogenesis of implanted bio-artificial liver using scaffolds. METHODS: This study used adipose tissue-derived stem cells that were collected from adult patients with liver diseases with conditions similar to the liver parenchyma. Specifically, microfilaments were used to create an artificial membrane and maintain the structure of an artificial organ. After scratching the stomach surface of severe combined immunocompromised (SCID) mice (n=4), artificial scaffolds with adipose tissue-derived stem cells and type I collagen were implanted. Expression levels of angiogenesis markers including vascular endothelial growth factor (VEGF), CD34, and CD105 were immunohistochemically assessed after 30 days. RESULTS: Grossly, the artificial scaffolds showed adhesion to the stomach and surrounding organs; however, there was no evidence of angiogenesis within the scaffolds; and VEGF, CD34, and CD105 expressions were not detected after 30 days. CONCLUSIONS: Although implantation of cells into artificial scaffolds did not facilitate angiogenesis, the artificial scaffolds made with type I collagen helped maintain implanted cells, and surrounding tissue reactions were rare. Our findings indicate that type I collagen artificial scaffolds can be considered as a possible implantable biomaterial.

3D Printing Technology and Its Applications for Tissue/Organ Regeneration / 대한이식학회지

Three-dimensional (3D) printing, also known as additive manufacturing (AM), has been used frequently in regenerative or translational medicine. In addition, recent advances in 3D printing technologies have opened the door to 3D bio-printing, which uses cells, biocompatible materials, and scaffolding simultaneously to generate 3D functional tissues. Although tissue generation by bio-printing such as multilayered skin, bone, bladder, and vascular grafts has shown good results, there are still several challenges related to printing of entire organs, particularly modulation of vascular formation during organ regeneration. This article provides a background and introduction to bio-printing for creation of artificial organs and tissues.

Utilization of Three-dimensional Printing Technology for Manufacture of Artificial Organs / 生物医学工程学杂志

In this article, we introduce the principle, describe the utilization and discuss the future development of three-dimensional printing technology for manufacturing artificial organs.

Reviving the Salivary Cells – Pathway to New Horizon.

The ability to speak, swallow, masticate, taste food, and maintain a healthy oral cavity is heavily reliant on the presence of saliva. Hyposalivation underlying xerostomia after radiotherapyis still a major problem in the treatment of head and neck cancer. As saliva possesses self-cleansing and antibacterial capability, hyposalivation is known to deteriorate periodontal status and increases dental disease. Furthermore, hyposalivation causes mastication and swallowing problems, burning sensation of the mouth and dysgeusia. Currently available treatments for dry mouth are prescription for artificial saliva, moisturizers, and medications which induce salivation from the residual tissue.2 Such management techniques do not address the source of the problem that is a lack of functional saliva-producing acinar cells. This review focuses the restoration of functional salivary glands with advancing modalities such as gene therapy, tissue engineering, and stem cells.

Agenesis of right diaphragm in the adults a diagnostic dilemma.

Diaphragmatic agenesis is the most extreme form of congenital diaphragmatic defect, and it may be unilateral or bilateral. Diaphragmatic agenesis is a rare diagnosis, typically made early in infancy and is generally associated with other genetic anomalies, especially anueploidy syndromes. It is associated with a high mortality, if not treated in infancy. However, a few patients have survived till adulthood. In this report, we describe the case of an adult female who presented with progressive shortness of breath during third trimester of pregnancy with complete agenesis of the right side of the diaphragm. A new diaphragm was created using polypropylene mesh after which she improved symptomatically and the lung showed good expansion.

Experimental study on novel hybrid artificial trachea transplantation / 生物医学工程学杂志

We developed and designed a new type of artificial trachea. The basic structure of the artificial trachea was polytetrafluoroethylene vascular prosthesis linked with titanium rings on both sides. Dualmesh was sutured on titanium rings. This experimentation follows the replacement of trachea in dogs with a combined artificial trachea to investigate the feasibility of this type of prosthesis. Sixteen dogs were implanted with the combined artificial trachea after resection of 5 cm of cervical trachea. The 5 cm-long trachea of dogs on the necks were resected and the reconstruction of the defect of the trachea was performed with trachea prosthesis. According to the method of trachea reconstruction, the models were divided into 2 groups, artificial trachea implantation group (the control group, n = 8) and group of artificial trachea implantation with growth factor (the experimental group, n = 8). Then computer tomography scan (CT), bronchoscope and pathologic examination were conducted periodically to observe the healing state of the hybrid artificial trachea. None of the dogs died during operation of cervical segmental trachea construction. But four dogs in the control group died of apnea in succession because artificial trachea was displaced and the lumen was obstructed, while 2 dogs died in the experimental group. In the first month there was granulation around anastomosis with slight stenosis. The rest of dogs were well alive until they were sacrificed 14 months later. The mean survival time of the experimental group was longer than that of the control group. The rate of infection, anastomotic dehiscence, severe stenosis and accidental death in the experimental group were lower than the control group (P < 0.05). Artificial trachea was encapsulated by fibrous tissue and no mucous membrane was seen in the lumen of the artificial trachea. The artificial trachea can be used to reconstruction of the defect of the trachea with long-term survival of the animals. The unique design of artificial trachea reduces stenosis around anastomosis effectively but infections and split or displacement of the artificial trachea are still major problems affecting long-term survival of the animals. Application of growth factors to a certain extent promotes tissue healing by changing the local environment.

Detection method and pattern recognition of ginseng and American ginseng pieces by electronic nose / 中国中药杂志

<p><b>OBJECTIVE</b>To distinguish the ginseng and American ginseng pieces accurately and rapidly by electronic nose technology and principal component analysis (PCA) method.</p><p><b>METHOD</b>The optimum conditions of electronic nose for ginseng and American ginseng pieces, such as sample size and volume, headspace volume, incubation time and temperature were determined by the orthogonal test, the data were processed by the normalization method and the preprocessed data were analyzed PCA.</p><p><b>RESULT</b>The detection methods of ginseng and American ginseng pieces was established by electronic nose, and the odor fingerprint figures of ginseng and American ginseng pieces were obtained, and ginseng and American ginseng pieces were distinguished by PCA recognition pattern.</p><p><b>CONCLUSION</b>A new accurate and rapid method to distinguish ginseng and American ginseng pieces was established by electronic nose detection.</p>

Research and design of an initiative lung simulator based on plunger / 中国医疗器械杂志

This article introduces the working principle and the structural design of an initiative lung simulator based on plunger. The lung simulator is intended to test the monitor parameter and trigger function of the ventilator. Lung simulator can ventilate initiatively by adjusting the parameters such as tidal volume(VT). frequency and inspiration time.

Preliminary study on simulating sensory nerves of intestinal contents using ultrasound detecting system / 生物医学工程学杂志

Successful assessing intestinal lumen content with ultrasound signals might lay a strong basis for the development of the artificial anal sphincter. In the present study, we utilized a modified MLU02-212 ultrasonic gas bubble detector to test the distal part of proximal colon in each rabbit, for the group of twenty healthy New Zealand rabbits. Voltage signals of solid, liquid, gas and empty content of the lumen were collected and compared. The results indicated that there were significant differences among the voltage signals in the 4 conditions (P = 0.000), respectively. Multiple comparison showed significant differences existed in any pair of the four conditions (P = 0.000). Three signal non-overlapping regions existed in these 4 conditions. Thus it seemed that ultrasound could be utilized to distinguish various contents inside the intestinal lumen and could act as "artificial sensory nerve".

Extracorporeal membrane oxygenation, an anesthesiologist's perspective: Physiology and principles. Part 1.

Extracorporeal membrane oxygenation (ECMO) is an adaptation of conventional cardiopulmonary bypass techniques to provide cardiopulmonary support. ECMO provides physiologic cardiopulmonary support to aid reversible aspects of the disease process and to allow recovery. ECMO does not provide treatment of the underlying disease. The indications for ECMO support have expanded from acute respiratory failure to acute cardiac failure refractory to conventional treatments from wide patient subsets involving neonates to adults. Vascular access for ECMO support is either percutaneous through a single-site, dual-lumen bicaval cannula or transthoracic via separate cannulas. The modes of support are either veno-venous or veno-arterial ECMO. In this article, the physiologic aspects of ECMO support are outlined.

Coracoclavicular ligament reconstruction using autologous double-strand palmaris longus tendon and artificial ligament for the treatment of acromioclavicular joint dislocation / 中国骨伤

<p><b>OBJECTIVE</b>To investigate clinical effects of coracohumeral ligament reconstruction with autologous double-strand of long palmaris longus tendon and artificial ligament for the treatment of acromioclavicular joint dislocation.</p><p><b>METHODS</b>From April 2006 to June 2009, 31 patients with acromioclavicular joint dislocation were treated with coracohumeral ligament reconstruction using autologous double-strand palmaris longus tendon and artificial ligament. There were 18 males and 13 females, ranging in age from 18 to 60 years, with an average of 35 years. Twenty-six patients were acute trauma and other 5 patients were chronic trauma. Preoperative symptoms included different degrees of pain, restricted movement, and instability of acromioclaviecular joint. The X-ray showed acromioclavicular joint dislocation.</p><p><b>RESULTS</b>The patients had good incision union without vascular and nerve injuries. All the patients were followed up, and the average duration was 23 months. The JOA scores decreased from preoperative (38.8 +/- 1.5) to (73.2 +/- 1.1) at 1 month after operation,and (93.5 +/- 0.8)at the last follow-up. Twenty-eight patients got an excellent result, 2 good and 1 fair.</p><p><b>CONCLUSION</b>The reconstruction of coracohumeral ligament using autologous double-strand palmaris longus tendon and artificial ligament is an effective method for the treatment of acromioclavicular joint dislocation.</p>

Artificial bowel sphincters for severe fecal incontinence. Are they a solution?

Fecal incontinence is a debilitating and common problem with a profound effect on a patient's well being medically, socially, and economically. Non-operative management of this condition includes dietary modification, antidiarrheal medications, and biofeedback. Patients with severe incontinence can be divided into 2 categories. The first group includes patients with an identifiable and isolated anatomic sphincter defect who can expect 80% short-term surgical success using overlapping sphincteroplasty. The second group is patients who will not benefit from sphincteroplasty; fortunately, they are not obligated to permanent stomas. Artificial bowel sphincter [ABS] implantation is a well-established surgical technique, offers a chance for continence, restoration, and improved quality of life with significant functional success rate. The surgeon needs to understand how they function. They should be proficient in different procedure types and match these with the patient's need. Post-operative long-term follow-up continues to help surgeons better serve this type of patient population

Current state and development of artificial lungs / 生物医学工程学杂志

The artificial lung is a technical device for providing life support; it will be put in use when the natural lungs are failing and are not able to maintain sufficient oxygenation of the body's organ systems. From the viewpoint of long-term development, the artificial lung should be permanently implanted in the body, so that it will substitute for the human pulmonary function partially or completely. In this paper, four artificial lung technologies were expounded with reference to the development and research process of artificial lung. They were extracorporeal membrane oxygenation, intravascular artificial lung, implantable artificial lung, and pumpless extracorporeal lung assist. In this paper were described the structure of the four kinds of artificial lung, the working principle, and their advantages, disadvantages and indications. The prospect of artificial lung was evaluated in the light of the data from the existing animal experiments and from the clinical experience of the centers.

Influência do manuseio do balão autoinflável neonatal sobre o pico de pressão e o volume corrente / Peak pressure and tidal volume are affected by how the neonatal self-inflating bag is handled

OBJETIVO: Avaliar a influência do manuseio do ventilador pulmonar manual neonatal com bolsa autoinflável sobre pico de pressão e volume corrente. MÉTODOS: Estudo experimental com 141 profissionais de saúde (médicos, médicos residentes, fisioterapeutas, enfermeiros e técnicos de enfermagem) que ventilaram um pulmão artificial ajustado para reproduzir o pulmão de um recém-nascido a termo, utilizando ventilador pulmonar manual autoinflável com cinco diferentes modos de manuseio: com as duas mãos (10 dedos) e com uma mão, utilizando cinco, quatro, três e dois dedos. Valores de pico de pressão e volume corrente foram registrados pelo pulmão artificial. RESULTADOS: Observou-se alta variabilidade nos valores das variáveis estudadas. A média do pico de pressão foi 39,73 cmH2O (IC95 por cento 37,32-42,13), variando de 2,5 a 106,3 cmH2O, e do volume foi 39,56 mL (IC95 por cento 36,86-42,25), variando de 4 a 88 mL. Não foi detectada influência significativa da profissão sobre as variáveis estudadas (p > 0,05). Observou-se que o modo de manuseio do ventilador pulmonar manual influenciou significativamente o pico de pressão e o volume corrente (p < 0,0001), que foram maiores quando o ventilador foi manuseado com as duas mãos. CONCLUSÃO: A maioria dos profissionais gerou pico de pressão e volume corrente muito elevados, principalmente quando foram empregadas as duas mãos para ventilar, aumentando o risco de barotrauma e volutrauma. Por outro lado, parte dos profissionais forneceu pressões e volumes tão baixos que seriam insuficientes para a adequada expansão pulmonar, podendo levar a hipoventilação. Tais riscos não dependeram da formação profissional.

OBJECTIVE: To evaluate how different ways of handling the neonatal self-inflating bag influence peak pressure and tidal volume. METHODS: This is an experimental study involving 141 different professionals (physicians, resident physicians, physiotherapists, nurses, and nursing technicians), who ventilated an artificial lung, adjusted to simulate the lung of a term neonate, using a self-inflating bag. Each professional handled the ventilator in five different ways: a) using both hands (10 fingers); and, with only one hand, b) five fingers, c) four fingers, d) three fingers, and e) two fingers. Peak pressure and tidal volume data were recorded by the artificial lung equipment. RESULTS: Both variables showed high variability, from 2.5 to 106.3 cmH2O (mean = 39.73 cmH2O; 95 percentCI 37.32-42.13) for peak pressure, and from to 4 to 88 mL (mean = 39.56 mL; 95 percentCI 36.86-42.25) for tidal volume. There was no significant influence of the profession on any of the variables (p > 0.05). However, bag handling significantly influenced both peak pressure and tidal volume (p < 0.0001), which were higher when the operator used both hands. CONCLUSION: The results indicate that most professionals delivered excessively high peak pressures and tidal volumes, which could increase the risk of barotrauma and volutrauma, especially when both hands were used to ventilate. On the other hand, a small number of professionals delivered insufficient pressure and volume for adequate lung expansion and ventilation. The delivery of inadequate ventilation was not dependent on profession.