Reciprocal inhibition and competitive hierarchy cause negative biodiversity-ecosystem function relationships.

The relationship between biodiversity and ecosystem function (BEF) captivates ecologists, but the factors responsible for the direction of this relationship remain unclear. While higher ecosystem functioning at higher biodiversity levels ('positive BEF') is not universal in nature, negative BEF relationships seem puzzlingly rare. Here, we develop a dynamical consumer-resource model inspired by microbial decomposer communities in pitcher plant leaves to investigate BEF. We manipulate microbial diversity via controlled colonization and measure their function as total ammonia production. We test how niche partitioning among bacteria and other ecological processes influence BEF in the leaves. We find that a negative BEF can emerge from reciprocal interspecific inhibition in ammonia production causing a negative complementarity effect, or from competitive hierarchies causing a negative selection effect. Absent these factors, a positive BEF was the typical outcome. Our findings provide a potential explanation for the rarity of negative BEF in empirical data.

Arthropod prey type drives decomposition rates and microbial community processes.

Microbial communities perform various functions, many of which contribute to ecosystem-level nutrient cycling via decomposition. Factors influencing leaf detrital decomposition are well understood in terrestrial and aquatic ecosystems, but much less is known about arthropod detrital inputs. Here, we sought to infer how differences in arthropod detritus affect microbial-driven decomposition and community function in a carnivorous pitcher plant, Sarracenia purpurea. Using sterile mesh bags filled with different types of sterile arthropod prey, we assessed if prey type influenced the rate of decomposition in pitcher plants over 7 weeks. Additionally, we measured microbial community composition and function, including hydrolytic enzyme activity and carbon substrate use. When comparing decomposition rates, we found that ant and beetle prey with higher exoskeleton content lost less mass compared with fly prey. We observed the highest protease activity in the fly treatment, which had the lowest exoskeleton content. Additionally, we saw differences in the pH of the pitcher fluid, driven by the ant treatment which had the lowest pH. According to our results from 16S rRNA gene metabarcoding, prey treatments with the highest bacterial amplicon sequence variant (ASV) richness (ant and beetle) were associated with prey that lost a lower proportion of mass over the 7 weeks. Overall, arthropod detritus provides unique nutrient sources to decomposer communities, with different prey influencing microbial hydrolytic enzyme activity and composition. IMPORTANCE: Microbial communities play pivotal roles in nutrient cycling via decomposition and nutrient transformation; however, it is often unclear how different substrates influence microbial activity and community composition. Our study highlights how different types of insects influence decomposition and, in turn, microbial composition and function. We use the aquatic pools found in a carnivorous pitcher plant as small, discrete ecosystems that we can manipulate and study independently. We find that some insect prey (flies) breaks down faster than others (beetles or ants) likely because flies contain more things that are easy for microbes to eat and derive essential nutrients from. This is also reflected in higher enzyme activity in the microbes decomposing the flies. Our work bridges a knowledge gap about how different substrates affect microbial decomposition, contributing to the broader understanding of ecosystem function in a nutrient cycling context.

Similar return to sport between double cortical button and docking techniques for ulnar collateral ligament reconstruction in baseball players.

BACKGROUND AND HYPOTHESIS: A double cortical button technique for ulnar collateral ligament reconstruction (UCLR) has advantages including significant control over graft tensioning, less concern about graft length, and minimized risk of bone tunnel fracture compared with traditional UCLR techniques. This double cortical button technique was recently found to be noninferior in mechanical performance to the traditional docking technique regarding joint strength, joint stiffness, and graft strain. However, clinical outcomes have not been compared between these UCLR techniques. Therefore, the purpose of this study was to determine whether baseball players who underwent UCLR with a double cortical button (double button) technique have similar return-to-sport (RTS) outcomes to baseball players who underwent UCLR with the traditional docking (docking) technique. MATERIALS AND METHODS: Baseball players who underwent primary UCLR from 2011 to 2020 across 2 institutions were identified. Included patients were contacted to complete a follow-up survey evaluating reoperations, RTS, and functional outcome scores. Functional outcome surveys include the Kerlan-Jobe Orthopaedic Clinic score, the Conway-Jobe score, the Andrews-Timmerman elbow score, and the Single Assessment Numeric Evaluation score. RESULTS: Overall, 78 male baseball players (age: 18.9 ± 2.4 years) with an average follow-up of 3.1 ± 2.4 years were evaluated, with 73 of the players being baseball pitchers. Players in the double button group more frequently received palmaris longus autografts (78% vs. 30%) and less frequently received gracilis autografts (22% vs. 58%) compared with players in the docking group (P = .001); however, all other demographic factors were similar between the groups. All players in the double button group were able to RTS in 11.1 ± 2.6 months, whereas 96% of players in the docking group were able to RTS in 13.5 ± 3.4 months (P > .05). All postoperative outcomes and patient-reported outcomes were statistically similar between the groups and remained similar after isolating pitchers only and after separating partial-thickness from full-thickness UCL tears (all P > .05). CONCLUSION: RTS and other postoperative outcomes may be similar between baseball players who underwent UCLR with the double button technique and the docking technique. Although future research may be necessary to strengthen clinical recommendations, these findings provide the first clinical outcomes in light of a recent cadaveric study finding similar elbow strength, joint stiffness, and graft strain compared with the docking technique.

Relationship between the elasticity of the forearm flexor-pronator muscles and elbow valgus torque in young baseball pitchers: a descriptive laboratory study.

BACKGROUND: The forearm flexor-pronator muscles act as a dynamic elbow stabilizer against elbow valgus load during baseball pitching. The elasticity of these muscles increases with pitching. However, it is unclear whether increased muscle elasticity is associated with greater elbow valgus torque during pitching. This study aimed to determine the relationship between the elasticity of the forearm flexor-pronator muscles and elbow valgus torque during pitching in young baseball pitchers. METHODS: We recruited 124 young baseball pitchers aged 9 to 12 years. The exclusion criteria included current pain with pitching, history of surgery on the tested extremity, or injuries on the tested extremity within the past 12 months. Before the examination, participants completed a questionnaire about their age, height, weight, dominant arm and practice time per week. The strain ratios of flexor carpi ulnaris (FCU), flexor digitorum superficialis (FDS), and pronator teres as the index of muscle elasticity were measured using ultrasound strain elastography. Participants pitched three fastballs at a distance of 52 ft 6 in (16 m) with maximum effort while wearing a sensor sleeve that recorded the elbow valgus torque. A multiple linear regression analysis was conducted to examine the association between muscle elasticity and elbow valgus torque, adjusting for age, height, weight, and practice time. RESULTS: The final analysis included 107 pitchers. After adjusting for covariates, increased strain ratio of the FCU was significantly associated with greater elbow valgus torque (coefficients = 0.038, 95% confidence interval [CI], 0.016-0.059, P<.001). Similarly, increased strain ratio of the FDS was significantly associated with greater elbow valgus torque (coefficients = 0.027, 95% CI, 0.013-0.042, P<.001). CONCLUSION: The high elasticities of the FCU and FDS were associated with greater elbow valgus torque during pitching in young baseball pitchers. The high elasticity of these muscles is a protective response and may be necessary for young baseball pitchers with greater elbow valgus torque during pitching. Among young baseball pitchers with greater elbow valgus torque, those who are unable to produce the higher elasticities of these muscles could have greater elbow valgus load during pitching and be at a higher risk for elbow injuries. The measurement of the elasticities of the FCU and FDS may be useful for identifying young baseball pitchers at risk of sustaining elbow injuries.

The Contribution of Lower-Body Kinematics to Pitching and Hitting Performance in Baseball: Utilizing the OpenBiomechanics Project.

As markerless motion capture systems become more affordable than ever, it is becoming far easier to collect and analyze kinematic data on baseballers. To ensure this data can be used impactfully, coaches and practitioners should possess a good understanding of specific technique characteristics that are associated with enhanced performance in pitchers and hitters. This study used the open-source data provided by Driveline Baseball's OpenBiomechanics Project to evaluate the contribution of lower-body kinematics to pitch velocity and bat speed. In addition to correlational analyses to examine the association between discrete kinematic variables and performance, statistical nonparametric mapping was used to compare slow and fast velocity groups across the entirety of pitching and hitting motions from peak knee height to ball release/contact. It was found that rotation of the trail leg and extension of the lead knee were both associated with performance in pitchers and hitters. Consequently, coaches and practitioners should ensure that individuals possess an adequate level of strength and flexibility to facilitate optimal movement of the trail hip and lead knee during pitching and hitting movements. If deficiencies exist, then training programs should be designed to address these issues and eventually bring about an improvement in performance.

Replicated radiations in the South American marsh pitcher plants (Heliamphora) lead to convergent carnivorous trap morphologies.

PREMISE: The evolution of carnivorous pitcher traps across multiple angiosperm lineages represents a classic example of morphological convergence. Nevertheless, no comparative study to-date has examined pitcher evolution from a quantitative morphometric perspective. METHODS: In the present study, we used comparative morphometric approaches to quantify the shape space occupied by Heliamphora pitchers and to trace evolutionary trajectories through this space to examine patterns of divergence and convergence within the genus. We also investigated pitcher development, and, how the packing of pitchers is affected by crowding, a common condition in their natural environments. RESULTS: Our results showed that Heliamphora pitchers have diverged along three main axes in morphospace: (1) pitcher curvature; (2) nectar spoon elaboration; and (3) pitcher stoutness. Both curvature and stoutness are correlated with pitcher size, suggesting structural constraints in pitcher morphological evolution. Among the four traits (curvature, spoon elaboration, stoutness, and size), all but curvature lacked phylogenetic signal and showed marked convergence across the phylogeny. We also observed tighter packing of pitchers in crowded conditions, and this effect was most pronounced in curved, slender pitchers. CONCLUSIONS: Overall, our study demonstrates that diversification and convergent evolution of carnivory-related traits extends to finer evolutionary timescales, reinforcing the notion that ecological specialization may not necessarily be an evolutionary dead end.

Outcomes following arthroscopic posteromedial osteophyte resection and risk of future ulnar collateral ligament reconstruction.

BACKGROUND AND HYPOTHESIS: Despite successful return-to-sport (RTS) outcomes after posteromedial osteophyte resection, one possible consequence of osteophyte removal is increased stress on the ulnar collateral ligament (UCL), leading to a UCL injury. It is currently unknown how often overhead athletes who undergo isolated posteromedial osteophyte resection subsequently require UCL reconstruction (UCLR). Therefore, the purpose of this study was to report outcomes following arthroscopic resection of posteromedial osteophytes in overhead athletes and determine whether overhead athletes who underwent arthroscopic posteromedial osteophyte resection for posteromedial impingement went on to require UCL surgery. We hypothesized that there would be a high rate of RTS following osteophyte resection and that players who underwent arthroscopic posteromedial osteophyte resection would have a >10% risk of requiring subsequent UCLR or UCL repair. MATERIALS AND METHODS: All patients who underwent elbow arthroscopy from 2010-2020 at a single institution were reviewed. Patients were included if they underwent isolated arthroscopic posteromedial osteophyte resection without concomitant UCL surgery, were overhead athletes at the onset of posteromedial impingement symptoms, and had no history of elbow surgery. Primary outcomes included RTS rate, complications, and subsequent shoulder and/or elbow injury and surgery, as well as several patient-reported outcome measures (Kerlan-Jobe Orthopaedic Clinic score, Timmerman-Andrews elbow score, and Conway-Jobe score). RESULTS: Overall, 36 overhead athletes were evaluated at 5.1 ± 3.4 years postoperatively, including 28 baseball pitchers, 3 baseball catchers, 3 softball players, 1 tennis player, and 1 volleyball player. Of the overhead athletes, 77% were able to RTS; the mean Kerlan-Jobe Orthopaedic Clinic and satisfaction scores were 70 and 75, respectively; and 89% of athletes had either excellent (73%) or good (16%) Conway-Jobe scores at long-term follow-up. Subsequent UCLR was required in 18% of baseball pitchers (n = 5) at a median of 13 months postoperatively. Of the 5 UCLRs, 3 were performed shortly after posteromedial osteophyte resection (6, 7, and 13 months postoperatively) whereas the other 2 were performed at 6.2 and 7.5 years postoperatively. CONCLUSION: Following arthroscopic posteromedial osteophyte resection, 77% of athletes were able to RTS. Baseball pitchers who undergo arthroscopic resection of posteromedial osteophytes for posteromedial impingement have an 18% risk of subsequent UCLR.

Alternative oxidase (AOX) in the carnivorous pitcher plants of the genus Nepenthes: what is it good for?

BACKGROUND AND AIMS: The carnivorous pitcher plants of the genus Nepenthes have evolved modified leaves that act as pitcher traps. The traps are specialized for prey attraction, capture, digestion and nutrient uptake but not for photosynthetic assimilation. METHODS: In this study, we used antibodies against different photosynthetic (D1, Lhcb2, Lhcb4, RbcL) and respiratory-related (AOX, COXII) proteins for semi-quantification of these proteins in the assimilation part of the leaves and the pitcher traps of different Nepenthes species and hybrids. Different functional zones of the trap and the traps from different ontogenetic stages were investigated. The pitcher traps of the distantly related species Sarracenia purpurea ssp. venosa were used as an outgroup. In addition, chlorophyll fluorescence and infrared gas analysis were used for measurements of the net rate of photosynthesis (AN) and respiration in the dark (RD). KEY RESULTS: The pitcher traps contained the same or lower abundance of photosynthesis-related proteins in accordance with their low AN in comparison to the assimilation part of the leaves. Surprisingly, all traps contained a high amount of alternative oxidase (AOX) and low amount of cytochrome c oxidase subunit II (COX II) than in the assimilation part of the leaves. Thermal imaging did not confirm the role of AOX in pitcher thermogenesis. CONCLUSIONS: The pitcher traps contain a high amount of AOX enzyme. The possible role of AOX in specialized pitcher tissue is discussed based on knowledge of the role and function of AOX in non-carnivorous plants. The roles of AOX in prey attraction, balance between light and dark reactions of photosynthesis, homeostasis of reactive oxygen species, digestive physiology and nutrient assimilation are discussed.

Is workload associated with latissimus dorsi and teres major tears in professional baseball pitchers? An analysis of days of rest, innings pitched, and batters faced.

BACKGROUND: Latissimus dorsi (LD) and teres major (TM) tears have become increasingly recognized injuries in professional baseball pitchers. The purpose of this study was to determine whether workload, as measured by the number of days of rest between outings, number of innings pitched, number of batters faced, and being a starting pitcher, is associated with an increased risk of sustaining an LD-TM tear in professional baseball pitchers. METHODS: All professional baseball pitchers who sustained an LD-TM tear between 2011 and 2017 were identified using the Major League Baseball Health and Injury Tracking System. A separate player-usage data set was used to determine workload. We then compared workload variables between pitcher-games 2, 6, 12, and >12 weeks prior to a documented LD-TM tear and pitcher-games from a non-LD-TM tear control group. In a paired analysis, we compared the acute workload (2, 6, and 12 weeks) prior to injury and the injured pitchers' non-acute workload >12 weeks prior to injury. RESULTS: A total of 224 unique LD-TM tears were documented in the Major League Baseball Health and Injury Tracking System database. In most periods, player-games with more innings pitched and more batters faced were associated with a higher incidence of subsequent LD-TM tears. The number of days of rest was not a significant predictor of an LD-TM tear in the acute workload setting, but pitchers who sustained an LD-TM injury averaged fewer days of rest over the previous ≥12 weeks than controls (P < .001). Pitchers who faced >30 batters per game showed a 1.57-fold increase in the percentage of pitchers with a subsequent LD-TM tear as compared with pitchers who faced ≤5 batters per game. Significantly more starting pitchers were in the case group that sustained LD-TM tears over multiple time points than in the control group. CONCLUSION: Having a greater pitcher workload and being a starting pitcher were associated with an increased risk of sustaining LD-TM tears in professional baseball players. The average number of days of rest was only a risk factor for LD-TM tears over a 3-month or longer period.

Chronic adaptations of the long head of the biceps tendon and groove in professional baseball pitchers.

BACKGROUND AND HYPOTHESIS: The long head of the biceps tendon (LHBT) plays a significant shoulder stabilizing role during pitching, with the large forces and repetitions involved in overhead throwing likely contributing to LHBT pathology. Determining whether the LHBT undergoes adaptive changes in baseball pitchers and how these changes relate to bicipital groove morphology can improve our understanding of the biceps function at the glenohumeral joint. Therefore, the purpose of this study was to determine the chronic adaptations of the bicipital groove morphology and the LHBT in professional baseball pitchers, with a secondary purpose of evaluating biceps integrity as it relates to torsional changes of the bicipital groove. We hypothesized that the throwing arm of professional baseball pitchers would exhibit chronic adaptations of the LHBT compared with their nonthrowing arm, and that these adaptations would be related to the bicipital groove morphology. MATERIALS AND METHODS: Fifty-three professional baseball pitchers were enrolled at the beginning of the 2015 Major League Baseball spring training. Ultrasound was used to bilaterally measure humeral retroversion and to capture images of the bicipital groove and the LHBT. MATLAB software was used to calculate the area of the bicipital groove, and ImageJ software was used to quantify the area, echogenicity, and circularity of the LHBT. RESULTS: The dominant arm LHBT cross-sectional area was significantly smaller than the nondominant arm (9 mm2 vs. 10 mm2; P = .011), whereas the dominant arm LHBT echogenicity was significantly higher than the nondominant arm (65 optical density vs. 59 optical density; P = .002). Pitchers with more bicipital groove rotational adaptation (more retroversion) had significantly more LHBT echogenicity adaptation compared with pitchers with less bicipital groove rotational adaptation (12 vs. 2; P = .023). CONCLUSION: There are significant bilateral differences in the LHBT of professional baseball pitchers. An adaptation in bony rotation was associated with a larger bilateral difference in LHBT echogenicity but was not related to bilateral differences in LHBT area or circularity. Therefore, the bilateral difference in echogenicity is impacted by bony morphology, whereas the bilateral difference in cross-sectional area may be independent of bony morphology in this healthy population.

Relationship between humeral retroversion and baseball positions during elementary and junior-high school.

BACKGROUND: Humeral retroversion is greater in the dominant shoulder than in the nondominant shoulder in baseball players. However, the effect of different baseball positions during childhood on humeral retroversion remains unknown. The purpose of this study was to investigate the following: (1) the relationship between humeral retroversion and baseball positions played during elementary and junior-high schools; (2) the association between humeral retroversion and the prevalence of pain during the medical checkup and self-reported history of injuries in the dominant shoulder or elbow. METHODS: We enrolled 149 male high-school baseball players who started playing baseball in elementary school. The subjects were classified into 3 groups according to their baseball positions in elementary and junior-high schools. All participants completed questionnaires regarding their current and past positions, current incidence and history of injuries in their shoulder or elbow joints, and the age they started playing baseball. Shoulder range of motion, humeral retroversion on ultrasonographic-assisted measurement, and the association between humeral retroversion and shoulder and elbow pain were evaluated. RESULTS: Humeral retroversion was significantly greater in the dominant shoulder than in the nondominant shoulder in all groups (P < .001). In addition, humeral retroversion in the dominant shoulder was significantly greater in players who were pitchers in both elementary and junior-high schools than in those who were fielders during both periods (96.2° and 89.4°, respectively; P = .02). Humeral retroversion in the dominant shoulder was positively correlated (P = .005, r = 0.23) with the length of career as a pitcher during elementary and junior-high schools. Humeral retroversion was not correlated with the prevalence of pain during the medical checkup or self-reported history of injuries in the dominant shoulder or elbow (P values ranging from 0.09-0.99). CONCLUSION: These results suggest that playing baseball as a pitcher during elementary school and junior-high school affects the increase in humeral retroversion in the dominant shoulder. Increased humeral retroversion in the dominant shoulder by repetitive throwing motion is an adaptive change, rather than a pathologic change.

Pitchers of Nepenthes khasiana express several digestive-enzyme encoding genes, harbor mostly fungi and probably evolved through changes in the expression of leaf polarity genes.

BACKGROUND: A structural phenomenon seen in certain lineages of angiosperms that has captivated many scholars including Charles Darwin is the evolution of plant carnivory. Evidently, these structural features collectively termed carnivorous syndrome, evolved to aid nutritional acquisition from attracted, captured and digested prey. We now understand why plant carnivory evolved but how carnivorous plants acquired these attributes remains a mystery. In an attempt to understand the evolution of Nepenthes pitcher and to shed more light on its role in prey digestion, we analyzed the transcriptome data of the highly specialized Nepenthes khasiana leaf comprising the leaf base lamina, tendril and the different parts/zones of the pitcher tube viz. digestive zone, waxy zone and lid. RESULTS: In total, we generated around 262 million high-quality Illumina reads. Reads were pooled, normalized and de novo assembled to generate a reference transcriptome of about 412,224 transcripts. We then estimated transcript abundance along the N. khasiana leaf by mapping individual reads from each part/zone to the reference transcriptome. Correlation-based hierarchical clustering analysis of 27,208 commonly expressed genes indicated functional relationship and similar cellular processes underlying the development of the leaf base and the pitcher, thereby implying that the Nepenthes pitcher is indeed a modified leaf. From a list of 2386 differentially expressed genes (DEGs), we identified transcripts encoding key enzymes involved in prey digestion and protection against pathogen attack, some of which are expressed at high levels in the digestive zone. Interestingly, many of these enzyme-encoding genes are also expressed in the unopened N. khasiana pitcher. Transcripts showing homology to both bacteria and fungi were also detected; and in the digestive zone, fungi are more predominant as compared to bacteria. Taking cues from histology and scanning electron microscopy (SEM) photomicrographs, we found altered expressions of key regulatory genes involved in leaf development. Of particular interest, the expression of class III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIPIII) and ARGONAUTE (AGO) genes were upregulated in the tendril. CONCLUSIONS: Our findings suggest that N. khasiana pitchers employ a wide range of enzymes for prey digestion and plant defense, harbor microbes and probably evolved through altered expression of leaf polarity genes.

Bone Mineral Density and Microstructure of the Elbow in Baseball Pitchers: An Analysis by Second-Generation HR-pQCT.

BACKGROUND: Baseball pitchers' elbows are exposed to repeated overloading during the throwing motion, which causes bone structural changes such as bone sclerosis and osteophyte formation. They have been observed by clinical CT and MRI, while the bone microstructural change has not yet been studied in vivo. The aims of this study were to establish a method of imaging the elbow joint using second-generation high-resolution peripheral quantitative CT and to investigate the bone microstructural change in baseball pitchers' dominant elbows. METHODS: The subjects were 17 baseball pitchers. The elbow was fixed using a custom-made cast and scanned by second-generation high-resolution peripheral quantitative CT. The scan conditions were as follows: voxel size 60.7 µm, integration time 43 ms, scan length 30.6 mm, and total scan time 8 min. Volumetric bone mineral density (vBMD) and trabecular bone microstructure were analyzed in the 6.5-mm3 cubic regions set in the capitellum and trochlea, and the dominant and nondominant elbows were compared. RESULTS: vBMD, bone volume fraction (BV/TV), and trabecular thickness (Tb.Th) at the capitellum were significantly higher in the dominant elbow than in the nondominant elbow. On the other hand, no parameters at the trochlea were significantly different. CONCLUSIONS: Higher vBMD accompanied by thicker trabecular bone was observed at the capitellum. These bone microstructural changes would reflect the valgus stress generated by the pitching motion in the elbow joint.

A case of bilateral acute depigmentation of the Iris in one of two identical twins.

BACKGROUND: Bilateral Acute Depigmentation of the Iris (BADI) is a condition which was first described in a case series from Turkey by Tugal-Tutkin and Urgancioglu in (Graefes Arch Clin Exp Ophthalmol 244:742-6, 2006). The condition is characterized by bilateral acute depigmentation and discoloration of the iris stroma, pigment dispersion, and deposition of pigment in the angle. In our case we report a patient who developed BADI after receiving pitcher plant extract injections for chronic migraine, while her identical twin sister has normal iris architecture and pigmentation and never received any pitcher plant injections. CASE PRESENTATION: Patient is a 41-year-old female with history of pitcher plant extract injections to her face for chronic migraine, who later developed bilateral depigmentation of the iris. She did not have any signs of anterior segment uveitis or iridocyclitis. She has an identical twin sister who maintained normal iris pigmentation during the entire course. CONCLUSIONS: Bilateral Acute depigmentation of the is a recently discovered condition described in the literature in Turkish patients (Tugal-Tutkun and Urgancioglu, Graefes Arch Clin Exp Ophthalmol 244:742-6, 2006; Tugal-Tutkun et al., Ophthalmology 116(8):1552-7, 2009). This condition affects mainly young females and is characterized by acute bilateral stromal depigmentation, without other pathologic ocular findings. These patients usually maintain normal vision and do not develop significant glaucoma from pigment collecting in the anterior chamber angle. This condition can be mistaken for Fuchs' heterochromic iridocyclitis, pigment dispersion syndrome, pseudoexfoliation syndrome, and viral iridocyclitis. This is the first reported case in North America and is important for differentiation from the above pathologies. Our patient had a history of pitcher plant extract injections to the face but it is unclear if this is associated with our patient's development of BADI. As awareness of this condition progresses, a possible etiology may be elucidated.

Importance of radar gun inclusion during return-to-throwing rehabilitation following ulnar collateral ligament reconstruction in baseball pitchers: a simulation study.

BACKGROUND: Rehabilitation following elbow ulnar collateral ligament reconstruction in baseball pitchers relies on a progression of pitching activities to ensure protection and gradual strengthening of the reconstructed ligament. The purpose of this study was to determine the medial elbow torque associated with pitches at various effort levels and determine whether radar gun assistance improves players' abilities to accurately match partial-effort pitches with true references based on maximum pitch velocity. METHODS: Thirty-seven healthy high school and collegiate baseball pitchers were included in this study. Participants were excluded if they were injured, recovering from injury, or otherwise not currently pitching at full effort. Pitch parameters were collected using a validated wearable sensor. Participants threw 5 pitches at 50%, 75%, and 100% subjective effort. Pitchers then threw 5 pitches at 50% maximum velocity and 75% maximum velocity, as measured by a radar gun. RESULTS: Thirty-seven pitchers completed this study. Pitches thrown at 50% and 75% partial effort were significantly faster and generated higher elbow torque than did pitches thrown at 50% and 75% velocity, respectively (P < .001). A 10% decrease in percentage of maximum velocity was associated with a 13% decrease in percentage of maximum elbow torque (ß coefficient = 1.3, R2 = 0.81, P < .001). CONCLUSION: Pitchers generate higher-than-intended forces when throwing at 50% and 75% effort during a subjective partial-effort throwing protocol. Use of a radar gun to guide partial-effort throwing during throwing rehabilitation programs may protect the reconstructed elbow from excess medial torque.

Superior Dispersal Ability Can Lead to Persistent Ecological Dominance throughout Succession.

A large number of descriptive surveys have shown that microbial communities experience successional changes over time and that ecological dominance is common in the microbial world. However, direct evidence for the ecological processes mediating succession or causing ecological dominance remains rare. Different dispersal abilities among species may be a key mechanism. We surveyed fungal diversity within a metacommunity of pitchers of the model carnivorous plant Sarracenia purpurea and discovered that the yeast Candida pseudoglaebosa was ecologically dominant. Its frequency in the metacommunity increased during the growing season, and it was not replaced by other taxa. We next measured its competitive ability in a manipulative laboratory experiment and tracked its dispersal over time in nature. Despite its dominance, C. pseudoglaebosa is not a superior competitor. Instead, it is a superior disperser: it arrives in pitchers earlier, and disperses into more pitchers, than other fungi. Differential dispersal across the spatially structured metacommunity of individual pitchers emerges as a key driver of the continuous dominance of C. pseudoglaebosa during succession.IMPORTANCE Microbial communities are ubiquitous and occupy nearly every imaginable habitat and resource, including human-influenced habitats (e.g., fermenting food and hospital surfaces) and habitats with little human influence (e.g., aquatic communities living in carnivorous plant pitchers). We studied yeast communities living in pitchers of the carnivorous purple pitcher plant to understand how and why microbial communities change over time. We found that dispersal ability is not only important for fungal communities early in their existence, it can also determine which species is dominant (here, the yeast Candida pseudoglaebosa) long after the species and its competitors have arrived. These results contrast with observations from many human-influenced habitats, in which a good competitor eventually outcompetes good dispersers, since humans often design these habitats to favor a specific competitor. This study will help microbiologists understand the qualities of microbial species that enable takeover of new habitats in both natural and human-influenced environments.

Jasmonate signalling in carnivorous plants: copycat of plant defence mechanisms.

The lipid-derived jasmonate phytohormones (JAs) regulate a wide spectrum of physiological processes in plants such as growth, development, tolerance to abiotic stresses, and defence against pathogen infection and insect attack. Recently, a new role for JAs has been revealed in carnivorous plants. In these specialized plants, JAs can induce the formation of digestive cavities and regulate enzyme production in response to different stimuli from caught prey. Appearing to be a new function for JAs in plants, a closer look reveals that the signalling pathways involved resemble known signalling pathways from plant defence mechanisms. Moreover, the digestion-related secretome of carnivorous plants is composed of many pathogenesis-related (PR) proteins and low molecular weight compounds, indicating that the plant carnivory syndrome is related to and has evolved from plant defence mechanisms. This review describes the similarities between defence and carnivory. It further describes how, after recognition of caught insects, JAs enable the carnivorous plants to digest and benefit from the prey. In addition, a causal connection between electrical and jasmonate signalling is discussed.

Species-specific differences determine responses to a resource pulse and predation.

The effects of resource pulses on natural communities are known to vary with the type of pulse. However, less is known about mechanisms that determine the responses of different species to the same pulse. We hypothesized that these differences are related to the size of the species, as increasing size may be correlated with increasing competitive ability and decreasing tolerance to predation. A factorial experiment quantified the magnitude and timing of species' responses to a resource pulse using the aquatic communities found in the leaves of the carnivorous pitcher plant, Sarracenia purpurea. We added prey to leaves and followed the abundances of bacteria and bacterivores (protozoa and rotifers) in the presence and absence of a top predator, larvae of the mosquito Wyeomyia smithii. Resource pulses had significant positive effects on species abundances and diversity in this community; however, the magnitude and timing of responses varied among the bacterivore species and was not related to body size. Larger bacterivores were significantly suppressed by predators, while smaller bacterivores were not; predation also significantly reduced bacterivore species diversity. There were no interactions between the effects of the resource pulse and predation on protozoa abundances. Over 67 days, some species returned to pre-pulse abundances quickly, others did not or did so very slowly, resulting in new community states for extended periods of time. This study demonstrates that species-specific differences in responses to resource pulses and predation are complex and may not be related to simple life history trade-offs associated with size.

Characterization of glenoid bone remodeling in professional baseball pitchers.

OBJECTIVE: To characterize the appearance, location, severity, and prevalence of focal glenoid retroversion on shoulder MRI in professional baseball pitchers versus age-matched controls. MATERIALS AND METHODS: In this retrospective review, two musculoskeletal radiologists evaluated shoulder MRI examinations from 40 professional baseball pitchers and 40 age-matched controls. Images were scored for the presence of a focal posterior glenoid convexity and the clock face positions involved. A consensus interpretation was also performed. A third reader identified the presence of additional shoulder abnormalities. RESULTS: After consensus, 60% (24/40) of pitchers were found to have focal glenoid retroversion versus 20% (8/40) of controls (p = 0.001). The most apparent location was posterior or posterior-superior, from 7.75 o'clock to 10.5 o'clock (median, 9.75 o'clock; interquartile range, 9.25-10 o'clock). The median clock angle of involvement was greater in pitchers than in controls (30° vs. 0°; p < 0.001). Interreader agreement regarding the presence or absence of focal glenoid retroversion was moderate (Cohen's kappa, 0.49). Focal glenoid retroversion was more prevalent among subjects with additional shoulder abnormalities (p = 0.014). CONCLUSIONS: Glenoid remodeling occurs in the throwing shoulder of professional baseball pitchers and manifests as focally convex morphology of the posterior or posterior-superior glenoid. This type of remodeling does not appear to be associated with a lower prevalence of injuries related to posterior-superior impingement.

Return to play after arthroscopic treatment for shoulder instability in elite and professional baseball players.

BACKGROUND: This study evaluated the clinical outcome of arthroscopic treatment for anterior shoulder dislocation in elite and professional baseball players. METHODS: This study included 51 baseball players who underwent arthroscopic Bankart repair between 2008 and 2015. The follow-up duration was set at 24 months or longer, based on clinic visit or telephone survey. After surgery, players who played in 1 or more official games were considered to have returned to play (RTP), and those who participated in more than 10 official games were considered to have solidly returned to play (sRTP). The RTP and sRTP rates were analyzed by player position (pitcher, catcher, and in-fielder), and the period of RTP after surgery (rehabilitation period) was investigated. RESULTS: Of 51 baseball players (mean age, 20.9 years), 14 were pitchers, 6 were catchers, and 31 were in-fielders. Pitchers showed 64% RTP and 57% sRTP, catchers, 83% RTP and 83% sRTP, and in-fielders, 90% RTP and 90% sRTP. The overall RTP and sRTP rates were 82% and 80%, respectively. The average RTP period after surgery (rehabilitation period) was 8.4 months, with 9.6, 9.1, and 7.4 months for pitchers, catchers, and in-fielders, respectively. CONCLUSIONS: The RTP after arthroscopic Bankart repair shows favorable results, with the nonthrowing shoulder and in-field position yielding the best results. Players undergoing arthroscopic Bankart repair and the surgeon should be aware of the possible outcomes based on the throwing/nonthrowing arm and various positions.