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ABSTRACT The apparent rarity of sex in many fungal species has raised questions about how much sex is needed to purge deleterious mutations and how differences in frequency of sex impact fungal evolution. We sought to determine how differences in the extent of recombination between populations of Aspergillus flavus impact the evolution of genes associated with the synthesis of aflatoxin, a notoriously potent carcinogen. We sequenced the genomes of, and quantified aflatoxin production in, 94 isolates of A. flavus sampled from seven states in eastern and central latitudinal transects of the United States. The overall population is subdivided into three genetically differentiated populations (A, B, and C) that differ greatly in their extent of recombination, diversity, and aflatoxin-producing ability. Estimates of the number of recombination events and linkage disequilibrium decay suggest relatively frequent sex only in population A. Population B is sympatric with population A but produces significantly less aflatoxin and is the only population where the inability of nonaflatoxigenic isolates to produce aflatoxin was explained by multiple gene deletions. Population expansion evident in population B suggests a recent introduction or range expansion. Population C is largely nonaflatoxigenic and restricted mainly to northern sampling locations through restricted migration and/or selection. Despite differences in the number and type of mutations in the aflatoxin gene cluster, codon optimization and site frequency differences in synonymous and nonsynonymous mutations suggest that low levels of recombination in some A. flavus populations are sufficient to purge deleterious mutations. IMPORTANCE Differences in the relative frequencies of sexual and asexual reproduction have profound implications for the accumulation of deleterious mutations (Muller’s ratchet), but little is known about how these differences impact the evolution of ecologically important phenotypes. Aspergillus flavus is the main producer of aflatoxin, a notoriously potent carcinogen that often contaminates food. We investigated if differences in the levels of production of aflatoxin by A. flavus could be explained by the accumulation of deleterious mutations due to a lack of recombination. Despite differences in the extent of recombination, variation in aflatoxin production is better explained by the demography and history of specific populations and may suggest important differences in the ecological roles of aflatoxin among populations. Furthermore, the association of aflatoxin production and populations provides a means of predicting the risk of aflatoxin contamination by determining the frequencies of isolates from low- and high-production populations.

The human papillomavirus type 16 (HPV16) L2 protein acts as a chaperone to ensure that the viral genome (vDNA) traffics from endosomes to the trans-Golgi network (TGN) and eventually the nucleus, where HPV replication occurs. En route to the nucleus, the L2/vDNA complex must translocate across limiting intracellular membranes. The details of this critical process remain poorly characterized. We have developed a system based on subcellular compartmentalization of the enzyme BirA and its cognate substrate to detect membrane translocation of L2-BirA from incoming virions. We find that L2 translocation requires transport to the TGN and is strictly dependent on entry into mitosis, coinciding with mitotic entry in synchronized cells. Cell cycle arrest causes retention of L2/vDNA at the TGN; only release and progression past G2/M enables translocation across the limiting membrane and subsequent infection. Microscopy of EdU-labeled vDNA reveals a rapid and dramatic shift in vDNA localization during early mitosis. At late G2/early prophase vDNA egresses from the TGN to a pericentriolar location, accumulating there through prometaphase where it begins to associate with condensed chromosomes. By metaphase and throughout anaphase the vDNA is seen bound to the mitotic chromosomes, ensuring distribution into both daughter nuclei. Mutations in a newly defined chromatin binding region of L2 potently blocked translocation, suggesting that translocation is dependent on chromatin binding during prometaphase. This represents the first time a virus has been shown to functionally couple the penetration of limiting membranes to cellular mitosis, explaining in part the tropism of HPV for mitotic basal keratinocytes.

Fungi produce a wealth of pharmacologically bioactive secondary metabolites (SMs) from biosynthetic gene clusters (BGCs). It is common practice for drug discovery efforts to treat species' secondary metabolomes as being well represented by a single or a small number of representative genomes. However, this approach misses the possibility that intraspecific population dynamics, such as adaptation to environmental conditions or local microbiomes, may harbor novel BGCs that contribute to the overall niche breadth of species. Using 94 isolates of Aspergillus flavus, a cosmopolitan model fungus, sampled from seven states in the United States, we dereplicate 7,821 BGCs into 92 unique BGCs. We find that more than 25% of pangenomic BGCs show population-specific patterns of presence/absence or protein divergence. Population-specific BGCs make up most of the accessory-genome BGCs, suggesting that different ecological forces that maintain accessory genomes may be partially mediated by population-specific differences in secondary metabolism. We use ultra-high-performance high-resolution mass spectrometry to confirm that these genetic differences in BGCs also result in chemotypic differences in SM production in different populations, which could mediate ecological interactions and be acted on by selection. Thus, our results suggest a paradigm shift that previously unrealized population-level reservoirs of SM diversity may be of significant evolutionary, ecological, and pharmacological importance. Last, we find that several population-specific BGCs from A. flavus are present in Aspergillus parasiticus and Aspergillus minisclerotigenes and discuss how the microevolutionary patterns we uncover inform macroevolutionary inferences and help to align fungal secondary metabolism with existing evolutionary theory.

The apparent rarity of sex in many fungal species has raised questions about how much sex is needed to purge deleterious mutations and how differences in frequency of sex impact fungal evolution. We sought to determine how differences in the extent of recombination between populations of Aspergillus flavus impact the evolution of genes associated with the synthesis of aflatoxin, a notoriously potent carcinogen. We sequenced the genomes of, and quantified aflatoxin production in, 94 isolates of A. flavus sampled from seven states in eastern and central latitudinal transects of the United States. The overall population is subdivided into three genetically differentiated populations (A, B, and C) that differ greatly in their extent of recombination, diversity, and aflatoxin-producing ability. Estimates of the number of recombination events and linkage disequilibrium decay suggest relatively frequent sex only in population A. Population B is sympatric with population A but produces significantly less aflatoxin and is the only population where the inability of nonaflatoxigenic isolates to produce aflatoxin was explained by multiple gene deletions. Population expansion evident in population B suggests a recent introduction or range expansion. Population C is largely nonaflatoxigenic and restricted mainly to northern sampling locations through restricted migration and/or selection. Despite differences in the number and type of mutations in the aflatoxin gene cluster, codon optimization and site frequency differences in synonymous and nonsynonymous mutations suggest that low levels of recombination in some A. flavus populations are sufficient to purge deleterious mutations.IMPORTANCE Differences in the relative frequencies of sexual and asexual reproduction have profound implications for the accumulation of deleterious mutations (Muller's ratchet), but little is known about how these differences impact the evolution of ecologically important phenotypes. Aspergillus flavus is the main producer of aflatoxin, a notoriously potent carcinogen that often contaminates food. We investigated if differences in the levels of production of aflatoxin by A. flavus could be explained by the accumulation of deleterious mutations due to a lack of recombination. Despite differences in the extent of recombination, variation in aflatoxin production is better explained by the demography and history of specific populations and may suggest important differences in the ecological roles of aflatoxin among populations. Furthermore, the association of aflatoxin production and populations provides a means of predicting the risk of aflatoxin contamination by determining the frequencies of isolates from low- and high-production populations.

Background Competent interpretation of esophageal high-resolution manometry ( HRM) is integral to a quality study. Currently, methods to assess physician competency for the interpretation of esophageal HRM do not exist. The aim of this study was to use formal techniques to (i) develop an HRM interpretation exam, and (ii) establish minimum competence benchmarks for HRM interpretation skills at the trainee, physician interpreter, and master level. Methods A total of 29 physicians from 8 academic centers participated in the study: 9 content experts separated into 2 study groups-expert test-takers (n=7) and judges (n=2), and 20 HRM inexperienced trainees ('trainee test-taker'; n=20). We designed the HRM interpretation exam based on expert consensus. Expert and trainee test-takers (n=27) completed the exam. According to the modified Angoff method, the judges reviewed the test-taker performance and established minimum competency cut scores for HRM interpretation skills. Key Results The HRM interpretation exam consists of 22 HRM cases with 8 HRM interpretation skills per case: identification of pressure inversion point, hiatal hernia >3 cm, integrated relaxation pressure, distal contractile integral, distal latency, peristaltic integrity, pressurization pattern, and diagnosis. Based on the modified Angoff method, minimum cut scores for HRM interpretation skills at the trainee, physician interpreter, and master level ranged from 65-80%, 85-90% (with the exception of peristaltic integrity), and 90-95%, respectively. Conclusions & Inferences Using a formal standard setting technique, we established minimum cut scores for eight HRM interpretation skills across interpreter levels. This examination and associated cut scores can be applied in clinical practice to judge competency. [ABSTRACT FROM AUTHOR]

Nutcracker esophagus ( NE), Jackhammer esophagus ( JHE), distal esophageal spasm ( DES), and hypertensive lower esophageal sphincter ( HTLES) are defined by esophageal manometric findings. Some patients with these esophageal motility disorders also have abnormal gastroesophageal reflux. It is unclear to what extent these patients' symptoms are caused by the motility disorder, the acid reflux, or both. The aim of this study was to determine the effectiveness of laparoscopic Nissen fundoplication ( LNF) on esophageal motility disorders, gastroesophageal reflux, and patient symptoms. Between 2007 and 2013, we performed high-resolution esophageal manometry on 3400 patients, and 221 patients were found to have a spastic esophageal motility disorder. The medical records of these patients were reviewed to determine the manometric abnormality, presence of gastroesophageal symptoms, and amount of esophageal acid exposure. In those patients that underwent LNF, we compared pre- and postoperative esophageal motility, gastroesophageal symptom severity, and esophageal acid exposure. Of the 221 patients with spastic motility disorders, 77 had NE, 2 had JHE, 30 had DES, and 112 had HTLES. The most frequently reported primary and secondary symptoms among all patients were: heartburn and/or regurgitation, 69.2%; respiratory, 39.8%; dysphagia, 35.7%; and chest pain, 22.6%. Of the 221 patients, 192 underwent 24-hour pH monitoring, and 103 demonstrated abnormal distal esophageal acid exposure. Abnormal 24-hour pH monitoring was detected in 62% of patients with heartburn and regurgitation, 49% of patients with respiratory symptoms, 36.8 % of patients with dysphagia, and 32.6% of patients with chest pain. Sixty-six of the 103 patients with abnormal 24-hour pH monitoring underwent LNF. Thirty-eight (13 NE, 2 JHE, 6 DES, and 17 HTLES) of these 66 patients had a minimum of 6-month postoperative follow-up that included clinical evaluation, esophageal manometry, and 24-hour pH monitoring. Postoperatively, all 38 patients had normal distal esophageal acid exposure. Of these 38 patients, symptoms resolved in 28 and improved in 10. Of six patients (one with NE, two JHE, and three with HTLES) that underwent postoperative esophageal manometry, five exhibited normal motility. Typical reflux symptoms are common among patients with esophageal hypermotility disorders. Abnormal 24-hour pH monitoring is present in the majority of patients with who report typical reflux symptoms and almost half of patients who report respiratory symptoms. Conversely, the majority of patients who report dysphagia or chest pain have normal distal esophageal acid exposure. Based on a small number of patients in this study, it also appears that motility disorders often improve after LNF. LNF is associated with resolution or improvement in reflux related symptoms and esophageal motility parameters in patients exhibiting abnormal esophageal acid exposure. This suggests that patient symptoms are due to abnormal acid exposure and not the motility disorder. [ABSTRACT FROM AUTHOR]

Background: There are limited studies that evaluate the efficacy of endoscopic fundoplication (EF) for gastroesophageal reflux disease (GERD) with the EsophyX™ device, especially with the most recent procedural iteration (TIF-2). This study was a prospective evaluation of our early experience with this device and procedure.Methods: Data were collected prospectively on 23 consecutive patients undergoing EF (March 2009 to August 2010). All patients completed a symptom questionnaire assessing frequency and severity of gastrointestinal and respiratory symptoms, 24-h pH, and manometry studies preoperatively and were encouraged to repeat these at 6 months.Results: All patients had abnormal pH studies and were on proton-pump inhibitor (PPI) therapy prior to EF. Median age was 47 years (19-62 years), and six (23%) were male. Nine (41%) patients had Body Mass Index (BMI) ≥ 30 kg/m(2), and three (14%) had a small hiatal hernia (≤ 2 cm). The procedure was aborted in two patients for retained food. Three patients underwent subsequent laparoscopic Nissen fundoplication for persistent or recurrent symptoms. Median hospitalization was 1 day, and there were no major perioperative complications. At 6 month follow-up, 19 (86%) patients completed a symptom questionnaire, and 14 (64%) and 11 (50%) patients underwent pH and manometry studies, respectively. There was a significant reduction in heartburn (P = 0.02), total percentage acid contact time (P = 0.002), DeMeester score (P = 0.002), and PPI use (P = 0.003). Overall, 8 out of 14 (57%) patients had abnormal pH studies and 11 out of 19 (58%) remained on PPI therapy at 6 months.Conclusion: EF with EsophyX™ is associated with significant reduction in heartburn and abnormal acid exposure at 6 months, although the majority of patients did not experience normalization of their pH studies and remained on PPI therapy. The procedure has an acceptable safety profile, but the question remains as to whether it is effective enough to warrant a place in the armamentarium for the treatment of GERD. [ABSTRACT FROM AUTHOR]

The article presents information on petroglyphs discovered in southeastern Colorado. The author notes that several different types of petrogylphs have been found with the best coming from Las Animas County, Colorado and that the report is designed to examine previous research on these images and discuss the relationship among them. Previous research has linked pictographs and petrogylphs to the plains cultures, but a link between the images in Colorado and those cultures has not been determined. Chipped or pecked into stone, the images discovered in Colorado along the Apishapa River depict goats, deer and buffalo.

The article presents an in-depth review of the geological study of the region of Trinidad, Colorado. Details are given overviewing several investigations by private and governmental officials since 1846. A comprehensive discussion of the various geological layers of the rock formations in Trinidad is given, pointing out the composition and characteristics of several historical epochs, including the Jurassic, Cretaceous, and Cenozoic eras. Lists and descriptions of dozens of local rock formations, fossils and minerals present are given.

The article presents information on archaeological surveys conducted in Las Animas County, Colorado. It is said that this county is both the largest in the state, and the least studied by archaeologists. This is due, in part, to the frequently inaccessible terrain, and a dearth of paved or marked roads. Many sites were surveyed in the region near Trinidad, and along the Purgatoire and Apishapa Rivers. Information is presented on the Native American artifacts found at these sites, such as stone implements, petroglyphs and projectile points.

The article reports on an archaeological survey that took place in Las Animas County, Colorado that began in June 1941. The report discusses the physical geography of Las Animas County, the geological aspects of the land and the peoples they believed occupied the sites surveyed. They believe the sites were populated by Plains Indians and suggest that the Ute, Kiowa and Apache all made camps within the county. It reports on the number of sites encountered and what types of sites they found. They found cave dwellings and stone enclosures and shelters. They also observed pictographs and petrogylphs.

The article presents a list of Native American relic collections and collectors in southern Colorado, including the F. Watson collection of Segundo, the W. R. Ross collection of Greeley, and the H. Valentine collection of Trinidad.

The article presents discussion of archaeological research projects which can be conducted in Colorado while resources are limited due to the national participation in World War II. Details are given noting the importance of classifying and analyzing previously collected data in the archaeological discipline and calls are given for further focus on such elements when resources are limited. Suggested projects include the identification of unreported sites, the discovery of previously unreported materials, and comprehensive synthesis of regional characteristics.

The article presents a discussion of the history of the calumet or peace-pipe of the Native Americans of Colorado. Comments are given outlining the significance of the pipe to Native American culture, noting its prevalence in several different societies in Minnesota. Details are given noting several instances of archaeological discoveries of pipes and their materials at a location in Trinidad, Colorado. Description is offered of the pipes found and the conditions of the site, along with speculation on its arrival in Colorado.

Preeclampsia (PE) is characterized by de novo hypertension (HTN) and is often associated with intrauterine growth restriction (IUGR). Hallmarks of PE are placental ischemia, decreased nitric oxide (NO) bioavailability, oxidative stress (OS), and organ damage in the kidneys and brain. This study aims to characterize a new model of PE using pregnant IUGR rats from hypertensive placental ischemic dams. It is hypothesized that pregnant IUGR rats from hypertensive placental ischemic dams will have elevated blood pressure (BP), OS, and organ damage. In this study, pregnant rats are divided into two groups: normal pregnant (NP) and hypertensive placental ischemic dams (RUPP). Offspring from NP and RUPP dams were mated at 10 weeks of age to generate pregnant IUGR (IUGR Preg) and pregnant control (CON Preg) rats. BP and other markers of PE were evaluated during late gestation. Pregnant IUGR rats had elevated BP and systemic OS. The maternal body weight of pregnant IUGR rats and their pups' weights were decreased, while the brains were enlarged with elevated OS. In summary, pregnant IUGR rats, born from hypertensive placental ischemic dams, have HTN and increased systemic and brain OS, with larger brain sizes and smaller pups. Furthermore, this study shows that pregnant IUGR rats exhibit a preeclamptic-like phenotype, suggesting a new epigenetic model of PE., (© 2024 The Author(s). Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)