A comparison of linear and daily undulating periodized programs with equated volume and intensity for local muscular endurance

The purpose of this study was to compare linear periodization (LP), daily undulating periodization (DUP), and reverse linear periodization (RLP) for gains in local muscular endurance and strength. Sixty subjects (30 men, 30 women) were randomly assigned to LP, DUP, or RLP groups. Maximal repetitions at 50% of the subject's body weight were recorded for leg extensions as a pretest, midtest, and posttest. Training involved 3 sets (leg extensions) 2 days per week. The LP group performed sets of 25 repetition maximum (RM), 20RM, and 15RM changing every 5 weeks. The RLP group progressed in reverse order (15RM, 20RM, 25RM), changing every 5 weeks. The DUP group adjusted training variables between each workout (25RM, 20RM, 15RM repeated for the 15 weeks). Volume and intensity were equated for each training program. No significant differences were measured in endurance gains between groups (RLP = 73%, LP = 56%, DUP = 55%; p = 0.58). But effect sizes (ES) demonstrated that the RLP treatment (ES = 0.27) was more effective than the LP treatment (control) and the DUP treatment (ES = -0.02) at increasing muscular endurance. Therefore, it was concluded that making gradual increases in volume and gradual decreases in intensity was the most effective program for increasing muscular endurance.     

Nitric oxide synthase type I (nNOS), vascular endothelial growth factor (VEGF) and myoglobin-like expression in skeletal muscle of Antarctic icefishes (Notothenioidei: Channichthyidae)

The Antarctic icefishes Channichthyidae lack haemoglobin and are thought to lack myoglobin (Mb) in their skeletal muscle as well. Due to the absence of both respiratory pigments, icefishes may present a variety of physiological adaptations in their skeletal muscles. In mammals, molecular responses to limiting oxygen availability in the skeletal muscle include, among others, the over expression of nitric oxide synthases (NOS), such as type I (neuronal nNOS) and type III (endothelial eNOS), as well as the vascular endothelial growth factor (VEGF). In this paper, we evaluated by western blot analysis whether the skeletal muscle of haemoglobin-less icefishes expresses in a constitutive manner higher levels of the type I and type III NOS isoforms and VEGF. Our results demonstrate that haemoglobin-less icefish of the family Channichthyidae do indeed present higher expression of the type I NOS isoform compared with red-blooded Antarctic fish species of other families of the same suborder Notothenioidei. In contrast, VEGF was not over-expressed. Moreover, we show that some icefish species, thought previously to lack Mb in oxidative muscles, actually present Mb-like immunoreactivity in their skeletal muscle.     

Golgi enzymes are enriched in perforated zones of golgi cisternae but are depleted in COPI vesicles

In the most widely accepted version of the cisternal maturation/progression model of intra-Golgi transport, the polarity of the Golgi complex is maintained by retrograde transport of Golgi enzymes in COPI-coated vesicles. By analyzing enzyme localization in relation to the three-dimensional ultrastructure of the Golgi complex, we now observe that Golgi enzymes are depleted in COPI-coated buds and 50- to 60-nm COPI-dependent vesicles in a variety of different cell types. Instead, we find that Golgi enzymes are concentrated in the perforated zones of cisternal rims both in vivo and in a cell-free system. This lateral segregation of Golgi enzymes is detectable in some stacks during steady-state transport, but it was significantly prominent after blocking endoplasmic reticulum-to-Golgi transport. Delivery of transport carriers to the Golgi after the release of a transport block leads to a diminution in Golgi enzyme concentrations in perforated zones of cisternae. The exclusion of Golgi enzymes from COPI vesicles and their transport-dependent accumulation in perforated zones argues against the current vesicle-mediated version of the cisternal maturation/progression model.     

Lipids shed into the culture medium by trypomastigotes of Trypanosoma cruzi

Trypomastigote forms of Trypanosoma cruzi were metabolically labeled with [14C]-ethanolamine and [3H]-palmitic acid. Lipids shed to the culture medium were analyzed and compared with the parasite components. Phosphatidylcholine and lysophosphatidylcholine accounted for 53% of the total incorporated precursor. Interestingly, phosphatidylethanolamine and its lyso derivative lysophosphatidylethanolamine, although present in significant amounts in the parasites, could not be detected in the shed material. Shed lipids were highly enriched in the desaturated fatty acids C16:1 and C18:1 when compared to the total fatty acid pool isolated from the parasites.     

Intra-Golgi transport: a way to a new paradigm?

The morpho-functional principles of intra-Golgi transport are, surprisingly, still not clear, which is in marked contrast to our advanced knowledge of the underlying molecular machineries. Recently, the conceptual and technological hindrances that had delayed progress in this area have been disappearing, and a cluster of powerful morphological techniques has been revealing new glimpses of the organization of traffic in intact cells. Here, we discuss the new concepts around the present models of intra-Golgi transport.     

T-cell-dependent hybrid resistance against a natural killer-resistant Moloney virus-induced lymphoma (YWA): in vitro generation of cytotoxic lymphocytes

A Moloney leukemia virus-induced lymphoma of the A.SW strain, YWA, was used to generate cytotoxic cells in vitro. Cocultivation of spleen cells from in vivo primed syngeneic and semisyngeneic mice with X-irradiated YWA tumor cells for 5 days resulted in a strong killing activity against YWA. The cytotoxicity was H-2 restricted and mediated by Thy-1.2-positive lymphocytes. F1 hybrids with variable degrees of natural resistance to the YWA tumor in vivo all generated cytotoxic cells after secondary stimulation in vitro but showed differences in optimal responder:stimulator requirements.     

2‐phenylethynesulphonamide (PFT‐μ) enhances the anticancer effect of the novel hsp90 inhibitor NVP‐AUY922 in melanoma,by reducing GSH levels

Heat shock proteins (HSPs), are molecular chaperones that assist the proper folding of nascent proteins. This study aims to evaluate the antitumour effects of the hsp90 inhibitor NVP‐AUY922 in melanoma, both in vitro and in vivo. Our results show that NVP‐AUY922 inhibits melanoma cell growth in vitro, with down regulation of multiple signalling pathways involved in melanoma progression such as NF‐?B and MAPK/ERK. However, NVP‐AUY922 was unable to limit tumour growth in vivo. Cotreatment of A375M xenografts with NVP‐AUY922 and PFT‐μ, a dual inhibitor of both hsp70 and autophagy, induced a synergistic increase of cell death in vitro, and delayed tumour formation in A375M xenografts. PFT‐μ depleted cells from the reduced form of glutathione (GSH) and increased oxidative stress. The oxidative stress induced by PFT‐μ further enhanced NVP‐AUY922‐induced cytotoxic effects. These data suggest a potential therapeutic role for NVP‐AUY922 used in combination with PFT‐μ, in melanoma.     

Loquat fruit size is increased through the thinning effect of naphthaleneacetic acid

The thinning effect of naphthaleneaceticacid was examined in loquat trees (Eriobotryajaponica Lindl.). The effect depended on theconcentration applied and on the treatment date. Themost effective treatment found to thin fruit andincrease the average fruit size was the application of20 mg l^–1 of naphthaleneacetic acid 10–15 daysafter anthesis. Treatment reduced the fruit resistanceto puncturing and improved total soluble solidsconcentration and coloration and, consequently,harvest time was markedly advanced.     

Improved NMR experiments with 13C-isotropic mixing for assignment of aromatic and aliphatic side chains in labeled proteins

Three improved ¹³C-spinlock experiments for side chain assignments of isotope labelled proteins in liquid state are presented. These are based on wide bandwidth spinlock techniques that have become possible with contemporary cryogenic probes. The first application, the H(C^aliC^aro)H-TOCSY, is an HCCH-TOCSY in which all CH_n moieties of a protein are detected in a single experiment, including the aromatic ones. This enables unambiguous assignment of aromatic and aliphatic amino acids in a single, highly sensitive experiment. In the second application, the ¹³C-detected C^all-TOCSY, magnetization transfer comprises all carbons—aliphatic, aromatic as well as the carbonyl carbons—making the complete carbon assignment possible using one spectrum only. Thirdly, the frequently used HC(CCO)NH experiment was redesigned by replacing the long C-carbonyl refocused INEPT transfer step by direct ¹³C–¹³C-TOCSY magnetization transfer from side chain carbons to the backbone carbonyls. The resulting HC(CCO)NH experiment minimizes relaxation losses because it is shorter and represents a more sensitive alternative particularly for larger proteins. The performance of the experiments is demonstrated on isotope labeled proteins up to the size of 43 kDa.     

Sensitivity and Acclimation of Three Canopy-Forming Seaweeds to UVB Radiation and Warming

Canopy-forming seaweeds, as primary producers and foundation species, provide key ecological services. Their responses to multiple stressors associated with climate change could therefore have important knock-on effects on the functioning of coastal ecosystems. We examined interactive effects of UVB radiation and warming on juveniles of three habitat-forming subtidal seaweeds from Western Australia–Ecklonia radiata, Scytothalia dorycarpa and Sargassum sp. Fronds were incubated for 14 days at 16–30°C with or without UVB radiation and growth, health status, photosynthetic performance, and light absorbance measured. Furthermore, we used empirical models from the metabolic theory of ecology to evaluate the sensitivity of these important seaweeds to ocean warming. Results indicated that responses to UVB and warming were species specific, with Sargassum showing highest tolerance to a broad range of temperatures. Scytothalia was most sensitive to elevated temperature based on the reduced maximum quantum yields of PSII; however, Ecklonia was most sensitive, according to the comparison of activation energy calculated from Arrhenius’ model. UVB radiation caused reduction in the growth, physiological responses and thallus health in all three species. Our findings indicate that Scytothalia was capable of acclimating in response to UVB and increasing its light absorption efficiency in the UV bands, probably by up-regulating synthesis of photoprotective compounds. The other two species did not acclimate over the two weeks of exposure to UVB. Overall, UVB and warming would severely inhibit the growth and photosynthesis of these canopy-forming seaweeds and decrease their coverage. Differences in the sensitivity and acclimation of major seaweed species to temperature and UVB may alter the balance between species in future seaweed communities under climate change.