A radiologic determination of the different screw cutting patterns in cut and uncut orthopedic cortical screws using a novel imaging technique.

OBJECTIVE: We hypothesize that cut screws will deform in a manner that increases the core and outer diameters of the screw hole compared to uncut controls, and effects will be more pronounced in titanium screws. MATERIALS AND METHODS: We used biomechanical polyurethane foam blocks to simulate cortical bone. We organized four groups of stainless steel and titanium cut and uncut screws. Blocks were fitted with a jig to ensure perpendicular screw insertion. We imaged the blocks using digital mammography and measured them using PACS software. Power analysis determined a power of 0.95 and an alpha error of 0.05. RESULTS: Highly statistically significant differences in core diameter were found after cutting stainless steel and titanium screws. Cutting stainless steel screws increased core diameter by 0.30 mm (95% CI, 0.16 to 0.45; p < .001). Titanium screws' core diameter increased by 0.45 mm (95% CI, 0.30 to 0.61; p < .001). No significant differences were found in the outer diameters of stainless steel and titanium screws after cutting. CONCLUSION: Titanium and stainless steel screw tracts demonstrated screw core diameter and screw thread pattern deformation after cutting. Titanium screws demonstrated more significant effects.

Cigarette Smoking Is Associated With Lower Quadriceps Cross-sectional Area and Attenuation in Older Adults.

INTRODUCTION: In addition to well-established links with cardiovascular and respiratory diseases, cigarette smoking may affect skeletal muscle; however, associations with quadriceps atrophy, density, and function are unknown. This study explored the associations of current and former smoking with quadriceps muscle area and attenuation as well as muscle force (assessed as knee extension peak torque) and rate of torque development-a measure of muscle power in older adults. METHODS: Data from 4469 older adults, aged 66-95 years at baseline in the Age, Gene/Environment Susceptibility-Reykjavik Study with measurements of thigh computed tomography, isometric knee extension testing, self-reported smoking history, and potential covariates were analyzed. RESULTS: Sex differences were observed in these data; therefore, our final analyses are stratified by sex. In men, both former smokers and current smokers had lower muscle area (with ß= -0.10, 95% confidence interval [CI] = -0.17 to -0.03 and ß = -0.19, 95% CI = -0.33 to -0.05, respectively) and lower muscle attenuation (ie, higher fat infiltration, ß = -0.08, 95% CI = -0.16 to -0.01 and ß = -0.17, 95% CI = -0.34 to -0.01, respectively) when compared with never smokers. Smoking status was not associated with male peak torque or rate of torque development. In women, current smoking was associated with lower muscle attenuation (ß = -0.24, 95% CI = -0.34 to -0.13) compared to never smoking. Among female smokers (current and former), muscle attenuation and peak torque were lower with increasing pack-years. CONCLUSIONS: Results suggest that cigarette smoking is related to multiple muscle properties at older age and that these relationships may be different among men and women. IMPLICATIONS: This article presents novel data, as it examined for the first time the relationship between smoking and computed tomography-derived quadriceps muscle size (cross-sectional area) and attenuation. This study suggests that current cigarette smoking is related to higher muscle fat infiltration, which may have significant health implications for the older population, because of its known association with poor physical function, falls, and hip fractures.

Resolved phylogeny and biogeography of the root pathogen Armillaria and its gasteroid relative, Guyanagaster.

BACKGROUND: Armillaria is a globally distributed mushroom-forming genus composed primarily of plant pathogens. Species in this genus are prolific producers of rhizomorphs, or vegetative structures, which, when found, are often associated with infection. Because of their importance as plant pathogens, understanding the evolutionary origins of this genus and how it gained a worldwide distribution is of interest. The first gasteroid fungus with close affinities to Armillaria-Guyanagaster necrorhizus-was described from the Neotropical rainforests of Guyana. In this study, we conducted phylogenetic analyses to fully resolve the relationship of G. necrorhizus with Armillaria. Data sets containing Guyanagaster from two collecting localities, along with a global sampling of 21 Armillaria species-including newly collected specimens from Guyana and Africa-at six loci (28S, EF1α, RPB2, TUB, actin-1 and gpd) were used. Three loci-28S, EF1α and RPB2-were analyzed in a partitioned nucleotide data set to infer divergence dates and ancestral range estimations for well-supported, monophyletic lineages. RESULTS: The six-locus phylogenetic analysis resolves Guyanagaster as the earliest diverging lineage in the armillarioid clade. The next lineage to diverge is that composed of species in Armillaria subgenus Desarmillaria. This subgenus is elevated to genus level to accommodate the exannulate mushroom-forming armillarioid species. The final lineage to diverge is that composed of annulate mushroom-forming armillarioid species, in what is now Armillaria sensu stricto. The molecular clock analysis and ancestral range estimation suggest the most recent common ancestor to the armillarioid lineage arose 51 million years ago in Eurasia. A new species, Guyanagaster lucianii sp. nov. from Guyana, is described. CONCLUSIONS: The armillarioid lineage evolved in Eurasia during the height of tropical rainforest expansion about 51 million years ago, a time marked by a warm and wet global climate. Species of Guyanagaster and Desarmillaria represent extant taxa of these early diverging lineages. Desarmillaria represents an armillarioid lineage that was likely much more widespread in the past. Guyanagaster likely evolved from a gilled mushroom ancestor and could represent a highly specialized endemic in the Guiana Shield. Armillaria species represent those that evolved after the shift in climate from warm and tropical to cool and arid during the late Eocene. No species in either Desarmillaria or Guyanagaster are known to produce melanized rhizomorphs in nature, whereas almost all Armillaria species are known to produce them. The production of rhizomorphs is an adaptation to harsh environments, and could be a driver of diversification in Armillaria by conferring a competitive advantage to the species that produce them.

Evolution of ectomycorrhizas as a driver of diversification and biogeographic patterns in the model mycorrhizal mushroom genus Laccaria.

A systematic and evolutionary ecology study of the model ectomycorrhizal (ECM) genus Laccaria was performed using herbarium material and field collections from over 30 countries covering its known geographic range. A four-gene (nrITS, 28S, RPB2, EF1α) nucleotide sequence dataset consisting of 232 Laccaria specimens was analyzed phylogenetically. The resulting Global Laccaria dataset was used for molecular dating and estimating diversification rates in the genus. Stable isotope analysis of carbon and nitrogen was used to evaluate the origin of Laccaria's ECM ecology. In all, 116 Laccaria molecular species were identified, resulting in a near 50% increase in its known diversity, including the new species described herein: Laccaria ambigua. Molecular dating indicates that the most recent common ancestor to Laccaria existed in the early Paleocene (56-66 million yr ago), probably in Australasia. At this time, Laccaria split into two lineages: one represented by the new species L. ambigua, and the other reflecting a large shift in diversification that resulted in the remainder of Laccaria. L. ambigua shows a different isotopic profile than all other Laccaria species. Isotopes and diversification results suggest that the evolution of the ECM ecology was a key innovation in the evolution of Laccaria. Diversification shifts associated with Laccaria's dispersal to the northern hemisphere are attributed to adaptations to new ecological niches.

Cantharellus chicagoensis sp. nov. is supported by molecular and morphological analysis as a new yellow chanterelle in midwestern United States.

Recent molecular systematic studies of Cantharellus cibarius sensu lato have revealed previously unknown species in different regions of North America. This study investigates yellow chanterelles in the Midwest using phylogenetic analysis of three DNA regions: nuc rDNA internal transcribed spacer 2 (ITS2) and 28S sequences and translation elongation factor 1α gene (EF1α). This analysis reveals a locally common taxon Cantharellus chicagoensis sp. nov. as distinct from sympatric species present in northeastern Illinois, northwestern Indiana and Wisconsin. This chanterelle features a pileus that often has a greenish yellow margin when immature, a squamulose disk when mature, a yellow spore print and the absence of a fragrant odor. Multiple Cantharellus specimens group with C. flavus and C. phasmatis, expanding their known range, and others with C. roseocanus Our observations highlight the diversity of Cantharellus in midwestern USA and further document the need for additional systematic focus on the region's fungi.

Examining the efficacy of a genotyping-by-sequencing technique for population genetic analysis of the mushroom Laccaria bicolor and evaluating whether a reference genome is necessary to assess homology.

Given the diversity and ecological importance of Fungi, there is a lack of population genetic research on these organisms. The reason for this can be explained in part by their cryptic nature and difficulty in identifying genets. In addition the difficulty (relative to plants and animals) in developing molecular markers for fungal population genetics contributes to the lack of research in this area. This study examines the ability of restriction-site associated DNA (RAD) sequencing to generate SNPs in Laccaria bicolor. Eighteen samples of morphologically identified L. bicolor from the United States and Europe were selected for this project. The RAD sequencing method produced anywhere from 290 000 to more than 3 000 000 reads. Mapping these reads to the genome of L. bicolor resulted in 84 000-940 000 unique reads from individual samples. Results indicate that incorporation of non-L. bicolor taxa into the analysis resulted in a precipitous drop in shared loci among samples, suggests the potential of these methods to identify cryptic species. F-statistics were easily calculated, although an observable "noise" was detected when using the "All Loci" treatment versus filtering loci to those present in at least 50% of the individuals. The data were analyzed with tests of Hardy-Weinburg equilibrium, population genetic statistics (FIS and FST), and population structure analysis using the program Structure. The results provide encouraging feedback regarding the potential utility of these methods and their data for population genetic analysis. We were unable to draw conclusions of life history of L. bicolor populations from this dataset, given the small sample size. The results of this study indicate the potential of these methods to address population genetics and general life history questions in the Agaricales. Further research is necessary to explore the specific application of these methods in the Agaricales or other fungal groups.

Cantharellaceae of Guyana II: new species of Craterellus, new South American distribution records for Cantharellus guyanensis and Craterellus excelsus, and a key to the Neotropical taxa.

Craterellus olivaceoluteus sp. nov. and Craterellus cinereofimbriatus sp. nov. are described as new to science. These fungi were collected from Guyana in association with ectomycorrhizal host trees in the genera Dicymbe (Fabaceae subfam. Caesalpinioideae) and Pakaraimaea (Dipterocarpaceae). Cantharellus guyanensis Mont., originally described from French Guiana, is redescribed from recent collections from Guyana, with additional range extensions for the species provided based on material examined from French Guiana, Venezuela, and north central, northeastern and southern Brazil, circumscribing nearly the entire Guiana Shield region and beyond. A new distribution record from French Guiana is provided for Craterellus excelsus T.W. Henkel & Aime. Macromorphological, micromorphological and habitat data are provided for the new species and C. guyanensis as well as DNA sequence data from the nuclear ribosomal regions of the internal transcribed spacer (ITS) and 28S large subunit (LSU); additional sequence data is provided for C. guyanensis and C. excelsus specimens collected outside Guyana. The relationships of these taxa within the Cantharellaceae were evaluated with phylogenetic analyses of ITS and LSU sequence data. This work brings the total number of Cantharellaceae species known from Guyana to eight. A key to the Cantharellus and Craterellus species known from the lowland Neotropics and extralimital montane Central and South America is provided.

Workers' Compensation: The Burden on Healthcare Resource Utilization After Foot and Ankle Surgery.

INTRODUCTION: The purpose of this study is to investigate the amount of healthcare resources dedicated to patients with WC after common foot or ankle procedures compared with a procedure-matched control group. METHODS: A retrospective review was performed of patients with WC and without WC undergoing foot and ankle procedures. Measures of healthcare burden included clinical communications, documents, prescriptions, office visits, and days to return to work and clinic discharge. RESULTS: Collectively, 142 patients met the inclusion criteria. Patients with workers' compensation had increased office communication encounters (P < 0.001), processed documents (P < 0.001), medication prescriptions (P < 0.001), number of office visits (P < 0.001), number of days until return to work (P < 0.001), and days until final disposition from clinic (P < 0.001). Patients with workers' compensation were more likely to have postoperative complications (OR 2.1; 95% CI, 1.0 to 4.3; P = 0.04), secondary surgeries (OR 8.2; 95% CI, 2.3 to 29.4; P < 0.001), and new complaints during the perioperative period (OR 1.9; 95% CI, 0.9 to 4.0; P = 0.07) but were less likely to cancel appointments (OR 0.41; 95% CI, 0.19 to 0.86; P = 0.02). DISCUSSION: When undergoing common foot and ankle orthopaedic procedures, patients with WC demonstrated increased healthcare utilization of resources. This included more office staff work burden dedicated to patients with WC for longer amounts of time, effectively doubling the effort of a non-WC cohort.

Applying a modified metabarcoding approach for the sequencing of macrofungal specimens from fungarium collections.

Premise: Fungaria are an underutilized resource for understanding fungal biodiversity. The effort and cost of producing DNA barcode sequence data for large numbers of fungal specimens can be prohibitive. This study applies a modified metabarcoding approach that provides a labor-efficient and cost-effective solution for sequencing the fungal DNA barcodes of hundreds of specimens at once. Methods: We applied a two-step PCR approach using nested, barcoded primers to sequence the fungal nrITS2 region of 766 macrofungal specimens using the Illumina platform. The specimens represent a broad taxonomic sampling of the Dikarya. Of these, 382 Lactarius specimens were analyzed to identify molecular operational taxonomic units (MOTUs) using a phylogenetic approach. The raw sequences were trimmed, filtered, assessed, and analyzed using the DADA2 amplicon de-noising toolkit and Biopython. The sequences were compared to the NCBI and UNITE databases and Sanger nrITS sequences from the same specimens. Results: The taxonomic identities derived from the nrITS2 sequence data were >90% accurate across all specimens sampled. A phylogenetic analysis of the Lactarius sequences identified 20 MOTUs. Discussion: The results demonstrate the capacity of these methods to produce nrITS2 sequences from large numbers of fungarium specimens. This provides an opportunity to more effectively use fungarium collections to advance fungal diversity identification and documentation.

Postoperative Infection and Revision Surgery Rates in Foot and Ankle Surgery Without Routine Prescription of Prophylactic Antibiotics.

INTRODUCTION: Surgical site infections (SSIs) are associated with patient morbidity and increased healthcare costs. Limited literature in foot and ankle surgery provides guidance about routine administration of postoperative antibiotic prophylaxis. The purpose of this study was to examine the incidence and revision surgery rates of SSI in outpatient foot and ankle surgeries in patients not receiving oral postoperative antibiotic prophylaxis. METHODS: A retrospective review of all outpatient surgeries (n = 1517) conducted by a single surgeon in a tertiary referral academic center was conducted through electronic medical records. Incidence of SSI, revision surgery rate, and associated risk factors were determined. The median follow-up was 6 months. RESULTS: Postoperative infection occurred in 2.9% (n = 44) of the surgeries conducted, with 0.9% of patients (n = 14) requiring return to the operating room. Thirty patients (2.0%) were diagnosed with simple superficial infections, which resolved with local wound care and oral antibiotics. Diabetes (adjusted odds ratio, 2.09; 95% confidence interval, 1.00 to 4.38; P = 0.049) and increasing age (adjusted odds ratio, 1.02; 95% confidence interval, 1.00 to 1.04; P = 0.016) were significantly associated with postoperative infection. DISCUSSION: This study demonstrated low postoperative infection and revision surgery rates without the routine prescription of prophylactic postoperative antibiotics. Increasing age and diabetes are signficant risk factors for developing a postoperative infection.

Ultrasound may safely replace chest radiograph after tube thoracostomy removal in trauma patients.

INTRODUCTION: A chest radiograph (CXR) is routinely obtained in trauma patients following tube thoracostomy (TT) removal to assess for residual pneumothorax (PTX). New literature supports the deference of a radiograph after routine removal procedure. However, many surgeons have hesitated to adopt this practice due to concern for patient welfare and medicolegal implications. Ultrasound (US) is a portable imaging modality which may be performed rapidly, without radiation exposure, and at minimal cost. We hypothesized that transitioning from CXR to US following TT removal in trauma patients would prove safe and provide superior detection of residual PTX. MATERIALS AND METHODS: A practice management guideline was established calling for the performance of a CXR and bedside US 2 h after TT removal in all adult trauma patients diagnosed with PTX at a level 1 trauma center. Surgical interns completed a 30-minute, US training course utilizing a handheld US device. US findings were interpreted and documented by the surgical interns. CXRs were interpreted by staff radiologists blinded to US findings. Data was retrospectively collected and analyzed. RESULTS: Eighty-nine patients met inclusion criteria. Thirteen (15%) post removal PTX were identified on both US and CXR. An additional 11 (12%) PTX were identified on CXR, and 5 (6%) were identified via US, for a total of 29 PTX (33%). One patient required re-intervention; the recurrent PTX was detected by both US and CXR. For all patients, using CXR as the standard, US displayed a sensitivity of 54.2%, specificity of 92.3%, negative predictive value of 84.5%, and positive predictive value of 72.2%. The cost of care for the study cohort may have been reduced over $9,000 should US alone have been employed. CONCLUSION: Bedside US may be an acceptable alternative to CXR to assess for recurrent PTX following trauma TT removal.

Transversus Abdominis Plane Block as Part of a Multimodal Analgesic Regimen in Patients Undergoing Anterior Lumbar Interbody Fusion: A Retrospective Cohort Study.

BACKGROUND: Opioids are a mainstay for pain control in patients undergoing lumbar spine surgery but are associated with a high risk of dependence and significant adverse effects. Efforts continue to be made to utilize non-narcotic agents such as regional nerve block for pain control as part of a multimodal analgesia regimen. Recently, transversus abdominis plane (TAP) blocks have proven beneficial for patients undergoing lumbar fusion procedures. The purpose of this study is to evaluate the efficacy of TAP blocks for postoperative pain control and the effect on opioid consumption and hospital length of stay (LOS) in patients undergoing anterior lumbar interbody fusion (ALIF). METHODS: A retrospective review of patients undergoing elective ALIF included collection of data on demographics, LOS, pain scores using visual analog scale (VAS), opioid consumption using morphine milligram equivalents (MME) from postoperative day (POD) 0 to 5, and any complications. Patients who underwent primary ALIF or ALIF with concomitant posterolateral lumbar fusion were included. RESULTS: A total of 99 patients met inclusion criteria; 47 had a preoperative TAP block and 52 did not. Demographic data and number of levels fused were equally distributed between the groups. The TAP group had significantly lower MME consumption postoperatively during POD 0 to 2 and 0 to 5. VAS pain scores were lower for TAP block patients on POD 3 and 4; otherwise, there was no significant difference. LOS and complication rates were not significantly different. A multiple regression analysis found male sex to be a predictor of increased postoperative MME, while age and TAP block were significant predictors of decreased MME. CONCLUSIONS: The use of TAP block for patients undergoing ALIF was associated with less cumulative MME consumption in the immediate postoperative period. TAP block may be an effective tool for reducing postoperative opioid consumption in patients undergoing ALIF. CLINICAL RELEVANCE: The data in this study provide clinical relevance supporting the use of TAP blocks for patients undergoing ALIF procedures.

Intraoperative Methadone Reduces Postoperative Opioid Requirements in Nuss Procedure for Pectus Excavatum.

INTRODUCTION: Surgical correction of pectus excavatum by Nuss procedure, commonly referred to as minimally invasive repair of pectus excavatum (MIRPE), often results in significant postoperative pain. This study investigated whether adding intraoperative methadone would reduce the postoperative opioid requirement during admission for patients undergoing MIRPE. METHODS: A retrospective cohort chart review was conducted for 40 MIRPE patients between 2018 and 2020. Patients were stratified into 2 groups: those who received multimodal anesthesia (MM, n = 20) and those who received multimodal anesthesia with the addition of intraoperative methadone (MM + M, n = 20). Data collected included total opioid consumption during hospital stay (morphine milligram equivalents [MMEs]), hospital length of stay (LOS), pain scores, time to ambulation, and time to tolerating solid food. RESULTS: Addition of intraoperative methadone for patients undergoing MIRPE significantly reduced postoperative opioid requirements (MME/kg) during admission (P = .007). On average, patients in the MM group received 1.61 ± .55 MME/kg while patients in the MM + M group received 1.16 ± .44 MME/kg. Hospital opioid (non-methadone) total was also significantly reduced between the MM (1.87 ± .54) and MM + M group (1.37 ± .46), P = .003. There was no significant difference in hospital opioid total MME/kg administered between the groups. There were no significant differences observed in hospital LOS, pain scores, time to ambulation, or time to toleration of solid food. DISCUSSION: Incorporating intraoperative methadone for patients undergoing MIRPE reduced postoperative opioid requirements and hospital opioid (non-methadone) totals without a significant change in pain scores. Patients undergoing the Nuss procedure may benefit from the administration of intraoperative methadone.

Does One Size Fit All? Variations in the DNA Barcode Gaps of Macrofungal Genera.

The nuclear ribosomal internal transcribed spacer (nrITS) region has been widely used in fungal diversity studies. Environmental metabarcoding has increased the importance of the fungal DNA barcode in documenting fungal diversity and distribution. The DNA barcode gap is seen as the difference between intra- and inter-specific pairwise distances in a DNA barcode. The current understanding of the barcode gap in macrofungi is limited, inhibiting the development of best practices in applying the nrITS region toward research on fungal diversity. This study examined the barcode gap using 5146 sequences representing 717 species of macrofungi from eleven genera, eight orders and two phyla in datasets assembled by taxonomic experts. Intra- and inter-specific pairwise distances were measured from sequence and phylogenetic data. The results demonstrate that barcode gaps are influenced by differences in intra- and inter-specific variance in pairwise distances. In terms of DNA barcode behavior, variance is greater in the ITS1 than ITS2, and variance is greater in both relative to the combined nrITS region. Due to the difference in variance, the barcode gaps in the ITS2 region are greater than in the ITS1. Additionally, the taxonomic approach of "splitting" taxa into numerous taxonomic units produces greater barcode gaps when compared to "lumping". The results show variability in the barcode gaps between fungal taxa, demonstrating a need to understand the accuracy of DNA barcoding in quantifying species richness. For taxonomic studies, variability in nrITS sequence data supports the application of multiple molecular markers to corroborate the taxonomic and systematic delineation of species.

Topical Antibiotic Powder and Nonunion Risk in Surgically Treated Tibial Plateau and Pilon Fractures.

INTRODUCTION: High-energy periarticular tibia fractures are challenging injuries with a significant risk of complications. Postoperative infection rates, although improved, remain unacceptable. Intrawound topical antibiotic (TA) application has been popularized to reduce postoperative infections. Although TA may minimize infections, it remains unclear whether TAs have any impact on the development of nonunion. Recent investigations of TA use in fracture care have questioned its efficacy in vivo and suggested a potentially deleterious effect on fracture healing. This study investigates the impact of TA on nonunion rates in surgically treated high-energy periarticular tibia fractures. METHODS: Retrospective analysis of surgically treated periarticular tibia fractures at a single Level 1 trauma center was conducted. Intervention in question was the clinical effect of intrawound TA powder application at definitive closure. A total of 222 high-energy periarticular tibia fractures were included, 114 with TA use and 108 without. The primary outcome was the occurrence of nonunion, with secondary outcomes being superficial and deep postoperative surgical site infections. RESULTS: Twenty-seven patients (12.1%) were diagnosed with nonunions (14 pilons and 13 plateaus). There was no statistically significant difference in nonunion rates among patients who received topical antibiotics (15.8%) versus the group of patients who did not (8.3%) ( P = 0.23). Odds of developing nonunion was significant for open injuries (odds ratio 6.16, P < 0.001) and patients with a provisional external fixator (odds ratio 8.72, P = 0.03) before definitive fixation. No notable difference in the number of superficial and deep infections was identified between groups. CONCLUSION: The use of TA in high-energy periarticular tibia fractures showed no statistically significant increase in nonunion rates but did not conclusively rule out nonunion as a possible effect of intrawound TA. Additional large-scale multicenter prospective studies are needed to confirm these findings. The current body of literature regarding high-energy periarticular tibia fractures does suggest that TAs lower the risk of postoperative infections, but the nonunion risk remains unclear. LEVEL OF EVIDENCE: Level III, Retrospective Cohort Study.

Diversity and evolution of ectomycorrhizal host associations in the Sclerodermatineae (Boletales, Basidiomycota).

This study uses phylogenetic analysis of the Sclerodermatineae to reconstruct the evolution of ectomycorrhizal host associations in the group using divergence dating, ancestral range and ancestral state reconstructions. Supermatrix and supertree analysis were used to create the most inclusive phylogeny for the Sclerodermatineae. Divergence dates were estimated in BEAST. Lagrange was used to reconstruct ancestral ranges. BayesTraits was used to reconstruct ectomycorrhizal host associations using extant host associations with data derived from literature sources. The supermatrix data set was combined with internal transcribed spacer (ITS) data sets for Astraeus, Calostoma, and Pisolithus to produce a 168 operational taxonomic unit (OTU) supertree. The ensuing analysis estimated that basal Sclerodermatineae originated in the late Cretaceous while major genera diversified near the mid Cenozoic. Asia and North America are the most probable ancestral areas for all Sclerodermatineae, and angiosperms, primarily rosids, are the most probable ancestral hosts. Evolution in the Sclerodermatineae follows the biogeographic history of disjunct plant communities associated with early Cenozoic mesophytic forests and a boreotropical history. Broad geographic distributions are observed in the most promiscuous Sclerodermatineae (those with broad host ranges), while those with relatively limited distribution have fewer documented ectomycorrhizal associations. This suggests that ectomycorrhizal generalists have greater dispersal capabilities than specialists.

Reconstructing the early evolution of Fungi using a six-gene phylogeny.

The ancestors of fungi are believed to be simple aquatic forms with flagellated spores, similar to members of the extant phylum Chytridiomycota (chytrids). Current classifications assume that chytrids form an early-diverging clade within the kingdom Fungi and imply a single loss of the spore flagellum, leading to the diversification of terrestrial fungi. Here we develop phylogenetic hypotheses for Fungi using data from six gene regions and nearly 200 species. Our results indicate that there may have been at least four independent losses of the flagellum in the kingdom Fungi. These losses of swimming spores coincided with the evolution of new mechanisms of spore dispersal, such as aerial dispersal in mycelial groups and polar tube eversion in the microsporidia (unicellular forms that lack mitochondria). The enigmatic microsporidia seem to be derived from an endoparasitic chytrid ancestor similar to Rozella allomycis, on the earliest diverging branch of the fungal phylogenetic tree.

Cantharellaceae of Guyana I: new species, combinations and distribution records of Craterellus and a synopsis of known taxa.

Members of the Cantharellaceae (Cantharellales, Basidiomycota) are common ectomycorrhizal associates of the leguminous genus Dicymbe in the Pakaraima Mountains of Guyana. Eight distinct species or morphospecies currently are recognized in Craterellus Pers. or Cantharellus Adans. ex Fr. from Guyanese Dicymbe-dominated forests. We evaluated the systematics of these taxa with phylogenetic analyses of DNA sequence data from the nuclear ribosomal regions of the internal transcribed spacer (ITS) and 28S large subunit (LSU). The results of these analyses along with careful assessment of morphology let us described two new species, Craterellus atratoides sp. nov. and Craterellus strigosus sp. nov., redescribe Craterellus atratus (Corner) Yomyart et al. based on new material from Guyana, and propose a new combination in Craterellus for Cantharellus pleurotoides T.W. Henkel, Aime & S.L. Mill. Macroscopic illustrations are provided for two additional cantharelloid morphospecies confirmed in Craterellus, as well as the regionally endemic Cantharellus guyanensis Mont. Macromorphological, micromorphological and habitat data are provided for C. atratoides, C. strigosus and C. atratus, and ITS and LSU sequence data are provided for each of the eight known Guyanese taxa.

Synovial chondromatosis of the flexor hallucis longus tendon sheath.

This case report discusses a rare case of secondary tenosynovial chondromatosis of the flexor hallucis longus (FHL). Synovial chrondomatosis is a rare, benign proliferative cartilaginous lesion arising from the synovial tissue or bursal lining of or near joints. When it is extra-articular, it is considered tenosynovial chondromatosis. The diagnosis is often delayed given the rarity of presentation and non-specific symptoms. The case was highly unusual in that hindfoot pain was caused by several centimetre-sized osteochondral bodies within the FHL tendon sheath. Anterior cheilectomy was performed. The patient returned to full activity following surgery without recurrence of the disease. The condition can be successfully treated operatively.

Host Shift Speciation of the Ectomycorrhizal Genus Suillus (Suillineae, Boletales) and Biogeographic Comparison With Its Host Pinaceae.

Suillus is a genus of ectomycorrhizal fungi associated almost exclusively with Pinaceae. Lack of sample collections in East Asia and unresolved basal phylogenetic relationships of the genus are the major obstacles for better understanding the Suillus evolution. A resolved phylogeny of Suillus representing global diversity was achieved by sequencing multiple nuclear ribosomal and protein coding genes and extensive samples collected in East Asia. Fungal fossils are extremely rare, and the Eocene ectomycorrhizal symbiosis (ECM) fossil of Pinus root has been widely used for calibration. This study explored an alternative calibration scenario of the ECM fossil for controversy. Ancestral host associations of Suillus were estimated by maximum likelihood and Bayesian Markov chain Monte Carlo (MCMC) analyses, inferred from current host information from root tips and field observation. Host shift speciation explains the diversification of Suillus major clades. The three basal subgenera of Suillus were inferred to be associated with Larix, and diverged in early Eocene or Upper Cretaceous. In the early Oligocene or Paleocene, subgenus Suillus diverged and switched host to Pinus subgenus Strobus, and then switched to subgenus Pinus four times. Suillus subgenus Douglasii switched host from Larix to Pseudotsuga in Oligocene or Eocene. Increased species diversity occurred in subgenus Suillus after it switched host to Pinus but no associated speciation rate shifts were detected. Ancestral biogeographic distributions of Suillus and Pinaceae were estimated under the Dispersal Extinction Cladogenesis (DEC) model. Ancestral distribution patterns of Suillus and Pinaceae are related but generally discordant. Dispersals between Eurasia and North America explain the prevalence of disjunct Suillus taxa.