Robotic microsurgical spermatic cord denervation for chronic orchialgia: a case series.

CONTEXT: Chronic orchialgia is a frustrating urologic condition that is commonly refractory to conservative modes of therapy. Microscopic spermatic cord denervation is a proven solution for patients who do not achieve relief from nonsurgical treatments. However, current widely used techniques require additional training in microsurgery. OBJECTIVE: To describe an adaptation and improvement of spermatic cord microdenervation technique that leveraged the robotic surgical training common for new urologists and is also accessible for urologists not specifically trained in microsurgery. METHODS: Robotic-assisted microdenervation of the spermatic cord was performed in three patients using a fluorescence vascular imaging tool to improve visualization of vascular structures (Firefly™; Innovative Surgical, Sunnyvale, CA, USA), along with a tissue matrix allograft to allow for better healing (AminoFix™; MiMedx®, Marietta, GA, USA). RESULTS: All three patients (100%) experienced postoperative resolution of their chronic orchialgia, and none reported any new pain. CONCLUSION: Utilization of robotic-assisted surgery offers more urologists the ability to use familiar techniques to treat chronic orchialgia when conservative measures are unsuccessful.

Impact of myoglobin oxygenation level on color stability of frozen beef steaks.

The emerging market of frozen meat emphasizes the need to better understand beef surface discoloration and the ideal parameters of freezing beef to retain an acceptable color. The objectives of this study were to determine the impacts of myoglobin oxygenation level prior to freezing and frozen storage duration on frozen beef color. USDA Choice strip loins (n = 36) were aged for 4 d or 20 d. Steaks were randomly assigned to a myoglobin oxygenation level [deoxygenated (DeOxy; immediately packaged after cutting), oxygenated (Oxy; oxygenated in air for 30 min), or highly oxygenated (HiOxy; packaged for 24 h in 80% O2)]. Steaks were then vacuum packaged in oxygen permeable or impermeable film and immediately frozen (-5 °C). Following either 0, 2, 4, or 6 mo of frozen storage, steaks were removed from the packaging and immediately analyzed for instrumental color (L*, a*, and b*), percent oxymyoglobin, metmyoglobin, and deoxymyoglobin, delta E, redness ratio, a*:b* ratio, hue angle, subjective discoloration, and lipid oxidation. The HiOxy steaks had greater oxygen penetration and the greatest a* values compared with DeOxy and Oxy steaks, regardless of packaging (P < 0.0005). With 4 d of aging, HiOxy steaks had greater a* values than DeOxy and Oxy at all storage times (P = 0.0118). The HiOxy steaks aged for 20 d and frozen for 6 mo had significantly higher delta E values than all other myoglobin oxygenation levels and postmortem aging periods (P < 0.0001). Redness and percent oxymyoglobin were highest for HiOxy steaks within each storage period (P < 0.0002). The HiOxy steaks had the highest percent oxymyoglobin and DeOxy had the lowest percent oxymyoglobin within each aging and storage period (P < 0.01). Conversely, DeOxy steaks had the highest percent metmyoglobin and HiOxy had the lowest percent metmyoglobin when packaged in impermeable film (P < 0.0001). The HiOxy steaks from 20 d of aging had the highest discoloration compared with 4 d aging and more discoloration than all other myoglobin treatments at 6 mo of storage (P < 0.0001). The HiOxy 20 d aged steaks exhibited the highest lipid oxidation values at 2, 4, and 6 mo (P = 0.0224) and HiOxy steaks exhibited a brighter and deeper cherry red color compared with the DeOxy steaks. The HiOxy steaks were greater in redness or similar when compared with Oxy steaks, but experienced more detrimental effects when frozen storage was extended.

Quality effects on beef strip steaks from cattle fed high-protein corn distillers grains and other ethanol by-products.

The objective of this study was to evaluate the effects of feeding high-protein corn distillers grains on fresh beef quality. Steers (n = 60) were fed one of five diets for 190 d (six pens with 10 cattle/pen/diet): a corn control (Control), 40% high-protein dry distillers grains plus solubles (HP-DDGS), 40% dry distillers grains plus solubles (DDGS), 40% wet distillers grains plus solubles (WDGS), or 40% bran plus solubles (Bran). Eighteen Choice carcasses (three cattle per pen) were randomly selected within each treatment; however, two carcasses were lost during carcass selection. Strip loins (Longissimus lumborum, IMPS # 180) were collected, divided into three equal portions, and aged for 2, 9, or 23 d. Steaks were fabricated following each aging period and placed under retail display (RD) conditions for 0, 4, or 7 d. Pen was the experimental unit. Hot carcass weight at harvest was 391 kg (SD 31.6 kg). Dietary treatment had no effect on tenderness (Warner-Bratzler shear force) within each aging period (P > 0.05). After 7 d of RD, following all aging periods, steaks from cattle fed HP-DDGS had the greatest visual discoloration except for DDGS and Bran after 23 d (P < 0.05). The steaks from cattle fed HP-DDGS had lower (P < 0.05) redness (a*) values than all other treatments following 7 d of RD. Lipid oxidation increased (P < 0.001) during RD at all aging periods, as measured via thiobarbituric acid reactive substance (TBARS). A day of RD-by-dietary treatment effect (P < 0.001) was observed for lipid oxidation. After 7 d of RD, steaks from cattle fed HP-DDGS had higher TBARS than all other treatments except WDGS (P < 0.01). A trend was found for sarcomere length (P = 0.07), with steaks from cattle fed Bran having the longest sarcomere length compared with all other treatments. An aging effect was found for free calcium content (P < 0.001) where steaks aged 9 and 23 d had significantly higher levels of free calcium than those aged 2 d. There was a tendency (P = 0.07) that steaks from cattle fed WDGS contained more free calcium than steaks from cattle fed DDGS or Bran. Although there were no statistical differences, there was a trend (P = 0.07) that steaks from cattle fed HP-DDGS had higher levels of PUFAs and C18:2. These results suggest that feeding high protein distillers grains has no detriment on tenderness, but may alter the lipid profile of the muscle, resulting in decreased color stability, increased lipid oxidation, and decreased shelf life.

Effect of Landfill Leachate on Cereal Nutrition and Productivity and on Soil Properties.

Landfill leachates carry nutrients, especially N and K, which can be recycled in cropping systems. We applied doses of landfill leachate (0 [Control], 32.7, 65.4, 98.1, and 130.8 m ha) three times in 2008 and three times in 2009 on a clay Rhodic Kandiudult soil. In 2009, black oat ( L.) and corn ( L.) were cropped in succession and assessed for concentration of nutrients in leaves and for shoot biomass and grain yield, respectively. As a positive control, an additional treatment with urea (120 kg ha of N) was studied in corn. Soil was sampled at four depths (down to 60 cm) in three sampling dates to assess chemical and biochemical properties. Concentration of nutrients in leaves, oat biomass (8530-23,240 kg ha), and corn grain yield (4703-8807 kg ha) increased with increasing doses of leachate. There was a transient increase in the concentration of nitrate in soil (3-30 mg kg), increasing the risk of N losses by leaching at doses above 120 kg ha N, as revealed by an estimated N balance in the cropping system. Sodium and K in soil also increased with increasing doses of leachate but decreased as rainfall occurred. The activity of dehydrogenase decreased about 30% from the control to the highest dose of leachate and urea, suggesting an inhibitory effect of mineral N on microbial metabolism. Landfill leachate was promising as a source of N and K for crop productivity and caused minor or transient effects on soil properties.

Tracking changes in chromosomal arrangements and their genetic content during adaptation.

There is considerable evidence for an adaptive role of inversions, but how their genetic content evolves and affects the subsequent evolution of chromosomal polymorphism remains controversial. Here, we track how life-history traits, chromosomal arrangements and 22 microsatellites, within and outside inversions, change in three replicated populations of Drosophila subobscura for 30 generations of laboratory evolution since founding from the wild. The dynamics of fitness-related traits indicated adaptation to the new environment concomitant with directional evolution of chromosomal polymorphism. Evidence of selective changes in frequency of inversions was obtained for seven of 23 chromosomal arrangements, corroborating a role for inversions in adaptation. The evolution of linkage disequilibrium between some microsatellites and chromosomes suggested that adaptive changes in arrangements involved changes in their genetic content. Several microsatellite alleles increased in frequency more than expected by drift in targeted inversions in all replicate populations. In particular, there were signs of selection in the O3+4 arrangement favouring a combination of alleles in two loci linked to the inversion and changing along with it, although the lack of linkage disequilibrium between these loci precludes epistatic selection. Seven other alleles increased in frequency within inversions more than expected by drift, but were not in linkage disequilibrium with them. Possibly these alleles were hitchhiking along with alleles under selection that were not specific to those inversions. Overall, the selection detected on the genetic content of inversions, despite limited coverage of the genome, suggests that genetic changes within inversions play an important role in adaptation.

Wing trait-inversion associations in Drosophila subobscura can be generalized within continents, but may change through time.

Clinal variation is one of the most emblematic examples of the action of natural selection at a wide geographical range. In Drosophila subobscura, parallel clines in body size and inversions, but not in wing shape, were found in Europe and South and North America. Previous work has shown that a bottleneck effect might be largely responsible for differences in wing trait-inversion association between one European and one South American population. One question still unaddressed is whether the associations found before are present across other populations of the European and South American clines. Another open question is whether evolutionary dynamics in a new environment can lead to relevant changes in wing traits-inversion association. To analyse geographical variation in these associations, we characterized three recently laboratory founded D. subobscura populations from both the European and South American latitudinal clines. To address temporal variation, we also characterized the association at a later generation in the European populations. We found that wing size and shape associations can be generalized across populations of the same continent, but may change through time for wing size. The observed temporal changes are probably due to changes in the genetic content of inversions, derived from adaptation to the new, laboratory environment. Finally, we show that it is not possible to predict clinal variation from intrapopulation associations. All in all this suggests that, at least in the present, wing traits-inversion associations are not responsible for the maintenance of the latitudinal clines in wing shape and size.

How much can history constrain adaptive evolution? A real-time evolutionary approach of inversion polymorphisms in Drosophila subobscura.

Chromosomal inversions are present in a wide range of animals and plants, having an important role in adaptation and speciation. Although empirical evidence of their adaptive value is abundant, the role of different processes underlying evolution of chromosomal polymorphisms is not fully understood. History and selection are likely to shape inversion polymorphism variation to an extent yet largely unknown. Here, we perform a real-time evolution study addressing the role of historical constraints and selection in the evolution of these polymorphisms. We founded laboratory populations of Drosophila subobscura derived from three locations along the European cline and followed the evolutionary dynamics of inversion polymorphisms throughout the first 40 generations. At the beginning, populations were highly differentiated and remained so throughout generations. We report evidence of positive selection for some inversions, variable between foundations. Signs of negative selection were more frequent, in particular for most cold-climate standard inversions across the three foundations. We found that previously observed convergence at the phenotypic level in these populations was not associated with convergence in inversion frequencies. In conclusion, our study shows that selection has shaped the evolutionary dynamics of inversion frequencies, but doing so within the constraints imposed by previous history. Both history and selection are therefore fundamental to predict the evolutionary potential of different populations to respond to global environmental changes.

From nature to the laboratory: the impact of founder effects on adaptation.

Most founding events entail a reduction in population size, which in turn leads to genetic drift effects that can deplete alleles. Besides reducing neutral genetic variability, founder effects can in principle shift additive genetic variance for phenotypes that underlie fitness. This could then lead to different rates of adaptation among populations that have undergone a population size bottleneck as well as an environmental change, even when these populations have a common evolutionary history. Thus, theory suggests that there should be an association between observable genetic variability for both neutral markers and phenotypes related to fitness. Here, we test this scenario by monitoring the early evolutionary dynamics of six laboratory foundations derived from founders taken from the same source natural population of Drosophila subobscura. Each foundation was in turn three-fold replicated. During their first few generations, these six foundations showed an abrupt increase in their genetic differentiation, within and between foundations. The eighteen populations that were monitored also differed in their patterns of phenotypic adaptation according to their immediately ancestral founding sample. Differences in early genetic variability and in effective population size were found to predict differences in the rate of adaptation during the first 21 generations of laboratory evolution. We show that evolution in a novel environment is strongly contingent not only on the initial composition of a newly founded population but also on the stochastic changes that occur during the first generations of colonization. Such effects make laboratory populations poor guides to the evolutionary genetic properties of their ancestral wild populations.