Three-dimensional scaffolds composed of biodegradable material

.. Three-dimensional scaffolds composed of biodegradable materials can provide platforms selleck chemicals Bortezomib for hepatocyte attachment (Fig. 1B). Fetal liver cells seeded in poly-L-lactic acid (PLLA) 3D macroporous scaffolds formed small clusters and showed higher levels of hepatic function, comparable with those of adult hepatocytes.21 Similarly, colonies of small hepatocytes (SHs), hepatic progenitor cells, placed on a collagen sponge with NPCs proliferated and expanded to form a hepatic organoid with highly differentiated functions.22 Hepatocytes seeded on PLLA and/or poly(D,L-lactide-co-glycolide) (PLGA) sponges were engrafted when they were implanted at a site associated with abundant vascular networks with appropriate surgical stimulation.

23,24 Both approaches for liver tissue reconstruction thus seems efficacious, since cell behavior can be controlled using materials with various structural and functional properties. However, these earlier studies using ECM or scaffold-based designs to engineer tissues face a major drawback, poor cell density. In native liver tissue, cell density is significantly higher, compared with other tissues, such as bone and cartilage. Accordingly, hepatocytes within native liver tightly interconnect to form layered structures, termed hepatic plates. Additionally, there is only a slight gap between hepatocytes and liver sinusoids, liver-specific microvessels, facilitating rapid exchange of macromolecules between plasma and hepatocytes. Thus, cell-sparse constructs engineered with those scaffolds often do not closely resemble the native liver architecture.

In contrast to earlier studies using ECM or biodegradable materials, scaffold-less cell-sheet engineering has been proposed for construction of 3D cell-dense liver tissue (Fig. 1C). For example, culture dishes, the surfaces of which were modified with a temperature-responsive polymer, have been used. Using such temperature-responsive culture surfaces, hepatocytes can be harvested as intact sheets and cell-dense thick tissues can be constructed by layering these cell sheets.25,26 However, a highly complex fabrication process is needed to covalently graft the temperature-responsive polymer onto dish surfaces27 and it also takes more than 30 min to harvest a cell sheet.28 Magnetite cationic liposomes have been also used to label cells and to form multilayered sheet architectures.

A magnetic field is then used to accumulate the magnetically-labeled cells onto ultralow attachment culture surfaces and form multilayered sheets.29 Cilengitide Cells can be harvested readily as intact cell sheets by pipetting. However, when this method was applied to hepatocytes, the sheets were not sufficiently strong for recovery.30 Furthermore, because cells have to be harvested as an intact sheet in the two methods above, it is difficult to construct the complex 3D liver architectures that are made from smaller tissue units.

Cohesion is understood as a ��dynamic process that is reflected i

Cohesion is understood as a ��dynamic process that is reflected in part by the tendency of a group to stick together and remain united in the pursuit of newsletter subscribe its instrumental objectives and/or for the satisfaction of member affective needs�� (Carron et al., 1998). The conceptual model of Carron et al. (1998) consists of four dimensions: Group integration-Task (GI-T), Group integration-Social (GI-S), Individual attraction to the group-Task (ATG-T), and Individual attraction to the group-Social (ATG-S). To create profiles according to this construct, this study divides cohesion into task and social dimensions because these dimensions have been shown to have more differences with respect to performance (Leo et al., 2010a). Carron et al.

��s (2002) meta-analysis demonstrated the importance of determining whether social or task aspects were related to performance. Their work identified studies that used only two dimensions and hence demonstrated problems with the presentation of the four factors of cohesion (Heuz�� et al., 2006; Leo et al., 2012). Thus, in this study, we differentiate between task cohesion, which reflects the degree to which group members work together to achieve common goals, and social cohesion, which reflects the degree to which team members empathise with each other and enjoy the group fellowship (Carron et al., 1998; Carron and Eys, 2012). These two dimensions are generated by environmental, personal, leadership and team factors that affect the perception of cohesion and produce individual and collective results, such as an influence on performance (Carron and Eys, 2012; Heuz�� et al.

, 2006; Leo et al., 2010; Paskevich et al., 1999). Many studies have assessed players�� and coaches�� opinions of team members�� efficacy (Bandura, 1997; Chase et al., 1997; Lent and L��pez, 2002). Three main types of sports-related team efficacy (Beauchamp, 2007) are noteworthy: perceived coach efficacy reflects a trainer��s confidence in a player��s abilities to perform given tasks (Beauchamp, 2007; Chase et al., 1997); perceived peer efficacy in sports represents players�� beliefs in their teammates�� abilities to accomplish a task successfully (Lent and L��pez, 2002); and collective efficacy is a group��s shared belief in its joint ability to organise and execute the courses of action required to produce certain achievement levels (Bandura, 1997).

Players form a perception of efficacy through these aspects, which lead to knowledge, affective and behavioural consequences, such as Drug_discovery increasing or decreasing sport performance (Beauchamp, 2007; Watson et al., 2001). Numerous investigations have found a positive relationship between both psychological constructs��cohesion and perceived efficacy��and sport performance (Heuz�� et al., 2006; Kozub and McDonnell, 2000; Leo et al., 2010a; Paskevich et al., 1999; Ramzaninezhad et al., 2009; Spink, 1990; Myers et al., 2007).

, 2010 ) It can be applied theoretically to any muscle or joint

, 2010 ). It can be applied theoretically to any muscle or joint of the body, and it can be worn up to four days selleck inhibitor without interfering with the daily hygiene and without modifying its adhesive properties ( Kase et al., 2003 ). The elimination of perspiration and freedom of motion are special KT characteristics that athletes appreciate ( Huang et al., 2011 ). Kase et al. (2003) proposed several taping mechanisms with various intended outcomes depending on how the tape was applied. Using these mechanisms, different beneficial effects could be achieved, including: (1) increasing proprioception, (2) normalizing muscle tension, (3) creating more space for improving circulation, (4) correcting muscle functioning by strengthening muscle weakness, and (5) decreasing pain.

Unfortunately, the limited research on the purported benefits of the KT has yielded contradictory results ( Garcia-Muro et al., 2010 ; Kaya et al., 2011 ; Paoloni et al., 2011 ; Thelen et al., 2008 ). Duathlon is a popular sports discipline that combines running, cycling and running in one event. Ankle mobility is essential for proper running technique, especially when pushing off ( Cejuela et al., 2007 ). During duathlon competitions it is quite common to experience soreness and cramping in the calf muscles due to overuse ( Merino-Marban et al., 2011 ). The fascia is a connective tissue that surrounds and covers muscles, which increases its tension in response to the mechanical load applied to the tissue during exercise ( O��Sullivan and Bird, 2011 ; Schleip et al., 2010 ).

One theory suggests that the KT could improve sports performance by unloading the fascia, thereby relieving pain, by reducing the mechanical load on free nerve endings within the fascia ( O��Sullivan and Bird, 2011 ; Schleip et al., 2010 ). Research based on samples of healthy athletes in order to test the effect of the KT on some aspect of performance are scarce and contradictory, and all conducted in laboratory settings ( Briem et al., 2011 ; Chang et al., 2010 ; Fu et al., 2008 ). To our knowledge, no randomized controlled research examining the effects of the KT on calf pain and ankle range of motion during competition has been carried out. Consequently, the purpose of this study was to examine the effect of the KT on calf pain and ankle dorsiflexion in duathletes immediately after its application and after a duathlon competition.

Material and Methods Participants A sample of 28 duathletes (6 females and 22 males) (age 29.11 �� 10.35 years; body height 172.57 �� 6.17 cm; body mass 66.63 �� 9.01 kg; body mass index 22.29 �� 2.00 kg/m 2 ) were recruited from the competitors in a duathlon sprint (5 km running + 20 km cycling + 2.5 km running). The participants were Drug_discovery recreational duathletes involved in regular training and competition (mean training 15.59 �� 6.56 hours per week, mean competition experience 6.41 �� 6.47 years).

According to Barbosa et al (2009), the use of aquatic cycling ha

According to Barbosa et al. (2009), the use of aquatic cycling has been reported in literature for three decades, though its findings are still contradictory. Alberton et al. (2010) suggest that HR in the water could be similar or higher as compared with dry land measurements. Barbosa et al. (2010) analyzed the relationships sellekchem between musical cadence and the physiological adaptations to basic head-out aquatic exercises. The study included an intermittent and progressive protocol and the main conclusion was that increasing musical cadence imposed an increase in the physiological response. In this context, several physiologic indicators have been used in order to quantify the intensity of exertion in those environments, such as: the HR (Sheldahl et al., 1984; Reilly et al., 2003); double product (Veloso et al.

, 2003), and blood lactate concentration (Di Masi et al., 2007). In water, resting or exercising induces different physiological responses when compared with those achieved in dry-land conditions (Shono et al., 2000; Reilly et al., 2003) and are affected by a number of factors, such as buoyancy, thermal conductivity of the water (Choukroun and Varene, 2000), hydrostatic pressure (Goodall and Howatson, 2008), among others. Those responses depend also on the body positioning in the water (Millet et al., 2002; Ega?a et al., 2006) and on the type of exercise (Barbosa et al., 2009). Kang et al. (2005) compared the responses of HR between intermittent (130 �� 2 bpm) and continuous cycling (127 �� 2 bpm) on land and did not found significant differences between both methods.

The lactate concentration was significantly higher at the end of the intermittent exercise with a mean value above 7 mmol in the final stage of the IP. Contrarily, Sabapathy et al. (2004), have examined the physiological responses in 10 subjects who performed a continuous and intermittent land cycling protocol and observed that the intermittent protocol was associated to significantly lower values of HR. Unfortunately, no previous study examined the type of physiological response induce by continue or intermittent exercise in water environment. Therefore, the present study tested the hypothesis that the type of exercise (continuous vs. intermittent) would affect the physiological response and the perception of effort during aquatic cycling. Methods Participants Ten women (values are mean �� SD: age=32.

8 �� 4.8 years; height=1.62 �� 0.05 cm; body mass=61.60 �� 5.19 kg; estimated body fat=27.13 �� 4.92%) of low risk, practicing regular classes of cycling in water for at least six months, participated in the study. All of them signed a written informed consent to participate in AV-951 the study and in accordance with the norms for accomplishment of research with humans established in the Helsinki Declaration of 1975. The experimental procedures were approved by the Ethics Committee of the Institution.