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Understanding how symbiotic associations differ across environmental gradients is key to predicting the fate of symbioses as environments change, and it is vital for detecting global reservoirs of symbiont biodiversity in a changing world. 1 , 2 , 3 However, sampling of symbiotic partners at the full-biome scale is difficult and rare. As Earth's largest terrestrial biome, boreal forests influence carbon dynamics and climate regulation at a planetary scale. Plants and lichens in this biome host the highest known phylogenetic diversity of fungal endophytes, which occur within healthy photosynthetic tissues and can influence hosts' resilience to stress. 4 , 5 We examined how communities of endophytes are structured across the climate gradient of the boreal biome, focusing on the dominant plant and lichen species occurring across the entire south-to-north span of the boreal zone in eastern North America. Although often invoked for understanding the distribution of biodiversity, neither a latitudinal gradient nor mid-domain effect 5 , 6 , 7 can explain variation in endophyte diversity at this trans-biome scale. Instead, analyses considering shifts in forest characteristics, Picea biomass and age, and nutrients in host tissues from 46° to 58° N reveal strong and distinctive signatures of climate in defining endophyte assemblages in each host lineage. Host breadth of endophytes varies with climate factors, and biodiversity hotspots can be identified at plant-community transitions across the boreal zone at a global scale. Placed against a backdrop of global circumboreal sampling, 4 our study reveals the sensitivity of endophytic fungi, their reservoirs of biodiversity, and their important symbiotic associations, to climate., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

In natural and agricultural systems, the plant microbiome-the microbial organisms associated with plant tissues and rhizosphere soils-has been shown to have important effects on host physiology and ecology, yet we know little about how these plant-microbe relationships play out in urban environments. Here we characterize the composition of fungal communities associated with living leaves of one of the most common sidewalk trees in the city of San Francisco, California. We focus our efforts on endophytic fungi (asymptomatic microfungi that live inside healthy leaves), which have been shown in other systems to have large ecological effects on the health of their plant hosts. Specifically, we characterized the foliar fungal microbiome of Metrosideros excelsa (Myrtaceae) trees growing in a variety of urban environmental conditions. We used high-throughput culturing, PCR, and Sanger sequencing of the internal transcribed spacer nuclear ribosomal DNA (ITS nrDNA) region to quantify the composition and structure of fungal communities growing within healthy leaves of 30 M. excelsa trees from six distinct sites, which were selected to capture the range of environmental conditions found within city limits. Sequencing resulted in 854 high-quality ITS sequences. These sequences clustered into 85 Operational Taxonomic Units (97% OTUs). We found that these communities encompass relatively high alpha (within) and beta (between-site) diversity. Because the communities are all from the same host tree species, and located in relatively close geographical proximity to one another, these analyses suggest that urban environmental factors such as heat islands or differences in vegetation or traffic density (and associated air quality) may potentially be influencing the composition of these fungal communities. These biogeographic patterns provide evidence that plant microbiomes in urban environments can be as dynamic and complex as their natural counterparts. As human populations continue to transition out of rural areas and into cities, understanding the factors that shape environmental microbial communities in urban ecosystems stands to become increasingly important., Competing Interests: The authors declare there are no competing interests., (©2023 Gibson and Zimmerman.)

Humans are inextricably linked to each other and our natural world, and microorganisms lie at the nexus of those interactions. Microorganisms form genetically flexible, taxonomically diverse, and biochemically rich communities, i.e., microbiomes that are integral to the health and development of macroorganisms, societies, and ecosystems. Yet engagement with beneficial microbiomes is dictated by access to public resources, such as nutritious food, clean water and air, safe shelter, social interactions, and effective medicine. In this way, microbiomes have sociopolitical contexts that must be considered. The Microbes and Social Equity (MSE) Working Group connects microbiology with social equity research, education, policy, and practice to understand the interplay of microorganisms, individuals, societies, and ecosystems. Here, we outline opportunities for integrating microbiology and social equity work through broadening education and training; diversifying research topics, methods, and perspectives; and advocating for evidence-based public policy that supports sustainable, equitable, and microbial wealth for all.

Boreal forests represent the world's largest terrestrial biome and provide ecosystem services of global importance. Highly imperilled by climate change, these forests host Earth's greatest phylogenetic diversity of endophytes, a hyperdiverse group of symbionts that are defined by their occurrence within living, symptomless plant and lichen tissues. Endophytes shape the ecological and evolutionary trajectories of plants and are therefore key to the function and resilience of terrestrial ecosystems. A critical step in linking the ecological functions of endophytes with those of their hosts is to understand the distributions of these symbionts at the global scale; however, turnover in host taxa with geography and climate can confound insights into endophyte biogeography. As a result, global drivers of endophyte diversity and distributions are not known. Here, we leverage sampling from phylogenetically diverse boreal plants and lichens across North America and Eurasia to show that host filtering in distinctive environments, rather than turnover with geographical or environmental distance, is the main determinant of the community composition and diversity of endophytes. We reveal the distinctiveness of boreal endophytes relative to soil fungi worldwide and endophytes from diverse temperate biomes, highlighting a high degree of global endemism. Overall, the distributions of endophytes are directly linked to the availability of compatible hosts, highlighting the role of biotic interactions in shaping fungal communities across large spatial scales, and the threat that climate change poses to biological diversity and function in the imperilled boreal realm.

This study sought to determine if traction through the index or long finger metacarpal provided a selective distraction force through either the distal radius' radial or ulnar column. In eight specimens, the radius was cut transversely 1 cm proximal to the Lister tubercle. Index and long finger metacarpals were cut and two-hole plates were fixed to metacarpals. Traction forces were alternately applied to index, then long finger metacarpals, sequentially through each metacarpal from 4.5N to 89N. Traction loading through the index finger metacarpal resulted in significantly more distraction force transmitted through the distal radius fragment's radial column at all force intervals. Traction loading through long finger metacarpal resulted in significantly higher force transmission through distal radius' ulnar column. In both cohorts, force transmission increased linearly in response to higher loads. Selective traction force of either the index or long finger metacarpal resulted in differential tensioning of the distal radius' ulnar and radial columns. (Journal of Surgical Orthopaedic Advances 28(2):104-107, 2019).

Fungal endophytes are diverse and widespread symbionts that occur in the living tissues of all lineages of plants without causing evidence of disease. Culture-based and culture-free studies indicate that they often are abundant in the leaves of woody angiosperms, but only a few studies have visualized endophytic fungi in leaf tissues, and the process through which most endophytes colonize leaves has not been studied thoroughly. We inoculated leaf discs and the living leaves of a model woody angiosperm, Populus trichocarpa , which has endophytes that represent three distantly-related genera ( Cladosporium , Penicillium , and Trichoderma ). We used scanning electron microscopy and light microscopy to evaluate the timeline and processes by which they colonize leaf tissue. Under laboratory conditions with high humidity, conidia germinated on leaf discs to yield hyphae that grew epiphytically and incidentally entered stomata, but did not grow in a directed fashion toward stomatal openings. No cuticular penetration was observed. The endophytes readily colonized the interiors of leaf discs that were detached from living leaves, and could be visualized within discs with light microscopy. Although they were difficult to visualize within the interior of living leaves following in vivo inoculations, standard methods for isolating foliar endophytes confirmed their presence., Competing Interests: The authors declare no conflict of interest.

A multicentre database was used to compare complications in 231 patients with an elevated International Normalized Ratio with 1626 control patients with a normal International Normalized Ratio. Patients with International Normalized Ratios measured within 48 hours of hand surgery were identified. Logistic regression models were used to assess the association between anticoagulation and reoperation rates, emergency department visits and hospital readmissions for the first 30 days after operation. The group with a raised International Normalized Ratio had a significantly higher Charlson Comorbidity Score. An elevated International Normalized Ratio was associated with an odds ratio for a post-operative emergency department visit of 3.3 and an odds ratio of 4.7 for readmission. There was no statistically significant difference in early reoperations between the two groups., Level of Evidence: III.

Arthritis and instability represent 2 of the most common pathological processes affecting the distal radioulnar joint (DRUJ). These conditions can present in isolation or as components of a multifactorial process. Nonoperative treatment is indicated for most acute injuries to the DRUJ. The joint should be immobilized in a position of stability to allow for ligament healing. Likewise, early arthritis responds favorably to rest, immobilization, corticosteroids, and nonsteroidal anti-inflammatory drugs (NSAIDs). When DRUJ instability is refractory to nonoperative measures, native ligament repair is the preferable method of treatment. When this method is not possible, anatomical reconstruction of the distal radioulnar ligaments should be performed. For advanced DRUJ arthritis Darrach resection should be reserved for the elderly, low-demand patient. The Sauve-Kapandji procedure allows for arthrodesis of the DRUJ while maintaining forearm rotation and a stable base for the ulnar carpus. DRUJ hemiarthroplasty procedures have been associated with favorable preliminary results. These implants attempt to reproduce native biomechanics and may be used in lieu of or as a salvage procedure after resection arthroplasty. DRUJ arthroplasty should be used as a salvage procedure.

The Xylariaceae (Sordariomycetes) comprise one of the largest and most diverse families of Ascomycota, with at least 85 accepted genera and ca. 1343 accepted species. In addition to their frequent occurrence as saprotrophs, members of the family often are found as endophytes in living tissues of phylogenetically diverse plants and lichens. Many of these endophytes remain sterile in culture, precluding identification based on morphological characters. Previous studies indicate that endophytes are highly diverse and represent many xylariaceous genera; however, phylogenetic analyses at the family level generally have not included endophytes, such that their contributions to understanding phylogenetic relationships of Xylariaceae are not well known. Here we use a multi-locus, cumulative supermatrix approach to integrate 92 putative species of fungi isolated from plants and lichens into a phylogenetic framework for Xylariaceae. Our collection spans 1933 isolates from living and senescent tissues in five biomes across the continental United States, and here is analyzed in the context of previously published sequence data from described species and additional taxon sampling of type specimens from culture collections. We found that the majority of strains obtained in our surveys can be classified in the hypoxyloid and xylaroid subfamilies, although many also were found outside of these lineages (as currently circumscribed). Many endophytes were placed in lineages previously not known for endophytism. Most endophytes appear to represent novel species, but inferences are limited by potential gaps in public databases. By linking our data, publicly available sequence data, and records of ascomata, we identify many geographically widespread, host-generalist clades capable of symbiotic associations with diverse photosynthetic partners. Concomitant with such cosmopolitan host use and distributions, many xylariaceous endophytes appear to inhabit both living and non-living plant tissues, with potentially important roles as saprotrophs. Overall, our study reveals major gaps in the availability of multi-locus datasets and metadata for this iconic family, and provides new hypotheses regarding the ecology and evolution of endophytism and other trophic modes across the family Xylariaceae., (Copyright © 2016 Elsevier Inc. All rights reserved.)

We surveyed endophytic fungal communities in leaves of a single tree species (Metrosideros polymorpha) across wide environmental gradients (500-5,500 mm of rain/y; 10-22 °C mean annual temperature) spanning short geographic distances on Mauna Loa Volcano, Hawai'i. Using barcoded amplicon pyrosequencing at 13 sites (10 trees/site; 10 leaves/tree), we found very high levels of diversity within sites (a mean of 551 ± 134 taxonomic units per site). However, among-site diversity contributed even more than did within-site diversity to the overall richness of more than 4,200 taxonomic units observed in M. polymorpha, and this among-site variation in endophyte community composition correlated strongly with temperature and rainfall. These results are consistent with suggestions that foliar endophytic fungi are hyperdiverse. They further suggest that microbial diversity may be even greater than has been assumed and that broad-scale environmental controls such as temperature and rainfall can structure eukaryotic microbial diversity. Appropriately constrained study systems across strong environmental gradients present a useful means to understand the environmental factors that structure the diversity of microbial communities.

Purpose: A variety of soft tissue surgical procedures have been developed for treatment of scapholunate (SL) dissociation. The purpose of this study was to compare the degree of correction obtained (as measured on preoperative and postoperative radiographs) when performing the modified Brunelli technique (MBT) with that of the more commonly performed Blatt capsulodesis (BC) and to evaluate each technique after simulated wrist motion., Methods: Five cadaver wrists were used for this study. The SL interval, SL angle, and radiolunate angle were recorded radiographically, with the SL ligament intact, for each wrist in several loaded positions: neutral, flexion, extension, radial deviation, ulnar deviation, and clenched fist. The SL interosseous ligament was then completely incised, and the radiographic measurements were repeated to demonstrate SL instability. The radiographic measurements were then repeated after MBT reconstruction and after BC reconstruction. Additional radiographic measurements were taken after simulated wrist motion., Results: Sectioning of the SL ligament resulted in radiographic evidence of SL dissociation. Use of the MBT demonstrated improved correction of the SL interval and the SL angle in the clenched fist position, which was statistically significant when compared with BC. The correction for the SL angle was maintained on the MBT specimens with simulated wrist motion., Conclusions: The results demonstrate that in this cadaver model, the MBT better restores the normal carpal relationship of the SL interval and SL angle when compared to the BC, as measured on radiographs. This correction might correlate with improved carpal dynamics and improved clinical outcomes., (Copyright © 2010. Published by Elsevier Inc.)

Background: This study attempts to confirm that the Disabilities of Arm, Shoulder and Hand (DASH) Outcome Measure self-administered questionnaire is valid specifically for ulnar neuropathy at the elbow. Validity of the Levine-Katz questionnaire for ulnar neuropathology compared with DASH was also studied., Materials and Methods: Forty-eight patients with isolated ulnar nerve surgery completed a 6-month evaluation. Patients were assigned a clinical stage. The DASH and Levine-Katz questionnaires were administered, and pinch and grip strength were measured preoperatively and postoperatively. Levine-Katz questionnaires were correlated with DASH to establish criterion validity. Construct validity was tested by determining a relationship between scores and clinical stages and by comparing scores preoperatively and postoperatively., Results: There was a high correlation between DASH scores and symptom severity and functional status. Although correlations were significant between DASH and biomechanical measures, correlation coefficients were lower. Postoperatively, all measures improved significantly., Conclusion: This study confirms that scores on the DASH questionnaire reflect the clinical staging of ulnar neuropathy at the elbow.

The static and dynamic stabilizers of the elbow and forearm axis are closely interrelated in elbow and forearm unit motion and load handling. An [figure: see text] understanding of elbow and forearm anatomy is crucial to the surgeon evaluating and treating complex pathologies resulting from acute or remote trauma.

One hundred fifty patients with suspected wrist ligamentous injuries were studied with both triple injection wrist arthrography and arthroscopy. The diagnoses obtained by these two techniques were compared to determine the differences between these two modalities. All the patients in this study had both the clinical diagnosis of ligamentous injuries of the wrist and normal findings on x-ray films. Intercarpal abnormalities were found in 106 patients (71%) at wrist arthrography and in 136 patients (91%) at arthroscopy. There was only 42% agreement (63 patients) between the arthrographic and arthroscopic diagnoses. Eighty-seven patients (58%) had alterations of their arthrographic diagnoses following arthroscopy. For patients with normal arthrographic findings (44 patients), 88% underwent arthroscopy because there was insufficient correlation between the physical examination findings and the arthroscopic findings. Out of the 44 patients with normal arthrographic findings, 35 patients (80% of the subgroup) had injuries found at arthroscopy. Over half of the patients had alterations in their arthrographic diagnoses following arthroscopy. In a patient with suspected ligamentous injury of the wrist, wrist arthroscopy may be the most efficient method in arriving at a definitive diagnosis.

This study reviews the clinical course of 22 patients with chronic renal failure on hemodialysis with ischemic or neurologic problems in the upper extremity distal to an arteriovenous fistula. Two distinct presentations were observed. Twelve patients developed significant motor and/or sensory impairment immediately following surgical construction of the fistula. Ten patients presented with upper extremity ischemia, established or impending tissue loss, or nonhealing wounds distal to a dialysis fistula. Seventeen of the 22 patients were diabetic. Nerve conduction studies, noninvasive vascular studies, and arteriography were used to confirm the diagnosis. Sixteen of the 22 patients had ligation or revision of the fistula. Five patients underwent amputations at the metacarpal or phalangeal level, and one patient underwent below-elbow amputation.

Fourteen patients were surgically treated for ulnar artery occlusion. Digital blood pressure measurements obtained pre- and intraoperatively helped guide the choice between ligation or reconstruction of the ulnar artery following resection of the occluded segment. The digital brachial index (DBI) was derived by calculating the ratio of digital blood pressure to the simultaneous brachial artery pressure. A DBI value of less than or equal to 0.7 was an indication for arterial reconstruction. If the DBI was greater than 0.7, resection of the occluded arterial segment without reconstruction was considered appropriate. Eight patients were treated by arterial reconstruction and six patients were treated with arterial resection. Seven of the eight reconstructed ulnar arteries were patent at follow-up evaluation by Doppler evaluation. DBI measurements obtained at follow-up were compared to preoperative values. In the reconstruction group, DBI change in the small, ring, and index fingers was positive, whereas it was negative in the resection group. Eleven patients indicated improvement from their presurgical status, although over half continued to experience pain on a regular basis. Reports of environmental and contact cold intolerance also showed improvement following surgery. Complaints of pain and cold intolerance were not significantly different between the resection and reconstruction groups at follow-up evaluation.

Arterial occlusive disease of the upper extremity is most often due to posttraumatic occlusion of the ulnar artery. An embolic source of the ischemia should be considered most strongly when sudden ischemia or vasospasm is associated with atrial fibrillation or follows a myocardial infarction. Connective tissue disorders and several arteridities are infrequent causes of upper-extremity occlusive disease and can usually be detected by a thorough peripheral vascular examination and blood studies. Atherosclerosis of the upper extremity is usually localized to the region of the subclavian artery and can present as a subclavian steal syndrome or arm ischemia. Finally, upper-extremity venous occlusive disease occurs in association with the hypercoagulable state, venous endothelial injury, or arises in otherwise healthy patients because of venous impingement in the thoracic outlet.

Cumulative trauma disorders are frequently responsible for the development of occupational neuropathy. Predisposing factors in the workplace are identified, and ergonomic principles to minimize these risks are presented.

Distal interphalangeal joint arthroplasty is effective in alleviating the pain of degenerative arthritis while preserving motion and stability. This procedure was undertaken as an alternative to arthrodesis for 17 women with osteoarthritis and 1 woman with rheumatoid arthritis. Silicone interpositional arthroplasty was performed in 31 digits of patients whose mean age was 58.3 years. The patients were evaluated at an average of 72.2 months (range, 12.6 to 123.1 months) after surgery. All patients reported that their primary preoperative symptom of pain was effectively eliminated by the procedure. At reevaluation, the active range of motion of the distal interphalangeal joint averaged 32.2 degrees and extension lag averaged 12.7 degrees . Lateral stability of the distal joint was present in all but one middle finger implant. Two implants were removed at 3 months postoperatively for wound problems and one at 31 months because of prothesis fracture.

A case of scapholunate dissociation with a dorsal carpal instability pattern is described in a skeletally immature 13-year-old male. The malrotation of the scaphoid was treated by soft tissue reconstruction, with use of a dorsal capsulodesis to provide a dorsal restraint to excessive palmar flexion of the scaphoid. In the skeletally immature carpus, isolated ligamentous injuries are less frequently recognized than epiphyseal injuries. To avoid interference with the successful conclusion of carpal growth, soft tissue reconstruction of deranged carpal relationships is preferable to intercarpal arthrodesis in the skeletally immature patient.

Ninety-ninety intraosseous wiring has been used in more than 150 cases over the last 4 years to obtain skeletal stability. This technique has been effective for the internal fixation of replanted parts, arthrodeses, transverse fractures, and elective free-tissue transfers. All osteotomies and fractures healed promptly, usually within 6 weeks. There have been no instances of nonunion, malunion, or implant failure. Only one wire had to be removed due to its prominence. Ninety-ninety intraosseous wiring is an expeditious, straightforward, and very stable method to secure rigid internal fixation and allow early active motion of the digital skeleton.

Plugs of cartilage and subchondral bone from patellae were subjected to cyclic compression consisting of rapid ramp loading for 0.3 seconds followed by a 2.7 second pause. At 1000 psi cyclic load, surface abrasion of the cartilage was noted at 250 cycles of compression. Primary fissures, which penetrated to the calcified cartilage, developed at 500 cycles. Secondary fissures, emanating from the primary fissures at 30 degrees-90 degrees angles, and penetrating to varying depths, were observed at 1000 cycles. Coalescence of fissures and undermining of cartilage fragments were noted at 8000 cycles. With greater loads, the same sequence of events occurred with fewer cycles except that primary fissures appeared before the surface was abraided. Fissure formation did not occur in specimens subjected to loads of 250 psi to 500 psi even if the superficial 100 micron of cartilage was removed and specimens were loaded for 120,860 cycles. The deeper layers of cartilage appear to be of prime importance in resisting fissure formation.

Twenty-three female patients had silicone interpositional arthroplasty of the distal interphalangeal joint in 38 digits. The operative indications were pain and deformity of the distal interphalangeal joint. The underlying diagnosis was osteoarthritis in all but one patient who had rheumatoid arthritis. The average age at the time of operation was 58.3 years. The implants have been in place for a mean period of 72.2 months (range, 12.6 to 123.1 months). At follow-up, extension lag averaged 12.7 degrees and the range of motion of the distal interphalangeal joint had a mean value of 33.2 degrees. Compared with arthrodesis, silicone interpositional arthroplasty offers the advantage of retained motion while preserving stability.

In a tri-institutional, retrospective study with long-term follow-up, forty-four patients who had multiple enchondromas were identified. Thirty-seven patients did not have hemangiomas (Ollier disease) and seven did (Maffucci syndrome). Of the thirty-seven patients who had Ollier disease, a low-grade chondrosarcoma developed in four; an astrocytoma, in one; and a granulosa-cell ovarian tumor, in one. In four of the seven patients who had Maffucci syndrome, there were six low-grade chondrosarcomas, one high-grade osteosarcoma, one pancreatic adenocarcinoma, one biliary adenocarcinoma, and one astrocytoma. None of the patients in either group died of the skeletal sarcoma, but four of five patients who had a non-skeletal malignant lesion died. From life-table analyses of these patients, we estimated that the incidence of secondary chondrosarcoma in patients who have Ollier disease is about 25 per cent at the age of forty years, and that malignant degeneration is almost a certainty in patients who have Maffucci syndrome. We concluded that periodic surveillance of the brain and abdomen for occult malignant lesions is indicated in patients who have enchondromatosis.