Combination platinum-based chemotherapy is the standard of care for first-line treatment of advanced urothelial carcinoma in patients who are suitable candidates for platinum-based therapy. Although chemotherapy is active (objective response in 40 to 50% of patients; disease control in 75 to 80%),…
Fri Sep 18, 2020 03:00
Kirsten rat sarcoma viral oncogene homologue (KRAS) is the most frequently mutated oncogene in human cancers and encodes a guanosine triphosphatase (GTPase) that cycles between active guanosine triphosphate (GTP)–bound and inactive guanosine diphosphate (GDP)–bound states to regulate signal…
Sun Sep 20, 2020 03:00
Overall survival among patients with advanced-stage KRASG12C non–small-cell lung cancer (NSCLC) or colorectal cancer is approximately 1 to 2 years; this startling statistic has fueled nearly four decades of research dedicated to the search for a KRAS-targeted drug. Because RAS has picomolar…
Sun Sep 20, 2020 03:00
Publication date: Available online 17 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Arnab Majumder, Shaina R. Eckhouse, L Michael Brunt, Michael M. Awad, Francesca M. Dimou, J Christopher Eagon, Sara Holden, Heather Fone, Jeffrey A. Blatnik
Fri Sep 18, 2020 18:37
Publication date: Available online 18 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Joseph D. Forrester, Mary T. Hawn
Fri Sep 18, 2020 18:37
Publication date: Available online 18 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Jecko Thachil
Fri Sep 18, 2020 18:37
Publication date: Available online 18 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Stavros Dimopoulos, Marianna Politou, Andreas Karabinis, Ioannis Vasileiadis
Fri Sep 18, 2020 18:37
Publication date: Available online 18 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Francisco Pimentel Cavalcante
Fri Sep 18, 2020 18:37
Publication date: Available online 18 September 2020Source: Journal of the American College of SurgeonsAuthor(s): John M. Clarke
Fri Sep 18, 2020 18:37
Publication date: Available online 18 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Michael R. Cassidy, Na Eun Kim, David McAneny
Fri Sep 18, 2020 18:37
Publication date: Available online 18 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Deborah Verran, Kim Templeton, Nicolas Sampron, Jonathan Braman, Pringl Miller
Fri Sep 18, 2020 18:37
Publication date: October 2020Source: Journal of the American College of Surgeons, Volume 231, Issue 4Author(s):
Fri Sep 18, 2020 18:37
Publication date: October 2020Source: Journal of the American College of Surgeons, Volume 231, Issue 4Author(s): George J. Chang
Fri Sep 18, 2020 18:37
Publication date: October 2020Source: Journal of the American College of Surgeons, Volume 231, Issue 4Author(s): Patricia Martinez Quinones, Amalia Cochran
Fri Sep 18, 2020 18:37
Publication date: October 2020Source: Journal of the American College of Surgeons, Volume 231, Issue 4Author(s): Raul Rosenthal
Fri Sep 18, 2020 18:37
Publication date: Available online 19 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Antonio Di Cataldo, Rosalia Latino, Salvatore Perrotti, Gregorio Di Franco, Desirée Gianardi, Luca Morelli
Sun Sep 20, 2020 21:14
Publication date: Available online 19 September 2020Source: Journal of the American College of SurgeonsAuthor(s): Warren Clements, Heather K. Moriarty, Gerard S. Goh, Jim Koukounaras
Sun Sep 20, 2020 21:14
Publication date: November 2020Source: Brain and Language, Volume 210Author(s): Carolin Dudschig, Barbara Kaup
Sun Sep 20, 2020 21:46
Isaac Schmale, MD, has completed a fellowship in neuro-rhinology and advanced endoscopic sinus surgery at the Texas Sinus Institute in...
Sun Sep 20, 2020 21:27
Soham Roy, MD, professor and Vice Chair for Academic Affairs & Quality in the Department of Otorhinolaryngology-Head and Neck Surgery...
Sun Sep 20, 2020 21:29
The Department of Otorhinolaryngology-Head and Neck Surgery at McGovern Medical School at UTHealth is investigating the efficacy and safety of...
Sun Sep 20, 2020 21:34
Scott Nickell was among the millions of people who suffer from difficulty breathing through the nose. Until recently his only...
Sun Sep 20, 2020 21:37
Approximately 30% of patients with non–small-cell lung cancer (NSCLC) present with resectable disease. Postoperative adjuvant cisplatin-based chemotherapy is recommended in patients with completely resected stage II to IIIA disease and — subject to postoperative evaluation to assess benefits and…
Sat Sep 19, 2020 03:00
Metastatic castration-resistant prostate cancer remains lethal. Men with deleterious alterations in genes involved in homologous recombination repair, such as BRCA1 and BRCA2, have more aggressive disease and higher mortality than those with proficient homologous recombination repair. The goal of…
Sun Sep 20, 2020 03:00
Laryngeal images obtained via high-speed videoendoscopy are an invaluable source of information for the advancement of voice science because they can capture the true cycle-to-cycle vibratory characteristics of the vocal folds in addition to the transient behaviors of the phonatory mechanism, such as onset, offset, and breaks. This information is obtained through relating the spatial and temporal features from acquired images using objective measurements or subjective assessments. While these images...
Fri Sep 18, 2020 03:00
This study investigates the perceptual and acoustic changes in student actors’ voices after 16 months of Linklater Voice training, which is a holistic method to train actors’ voices.
Fri Sep 18, 2020 03:00
There exist a cohort of transmasculine patients who remain dissatisfied with vocal function following testosterone therapy and voice training.
Sat Sep 19, 2020 03:00
The vast majority of motor learning studies investigating focus of attention have found that an external focus of attention (focusing on the effect of a movement) results in enhanced performance and learning, compared to an internal focus of attention (focusing on the body movement itself). The present study attempts to determine if the high incidence of internal focus of attention instruction that has been reported in the realm of athletics is replicated in voice training.
Sat Sep 19, 2020 03:00
The aim of the present study was to investigate the validity (both concurrent and diagnostic) and test-retest reliability of Acoustic Voice Quality Index (AVQI) version 2 (AVQI 02.06) in Turkish speaking population.
Sun Sep 20, 2020 03:00
The objective of this narrative review was to identify and evaluate published international guidelines on mandibular third molars (M3M) and to assess their clinical scope and the validity of the recommendations. The search strategy used data obtained from a variety of sources including MEDLINE, national regulatory bodies, national dental and surgical colleges and associations, and military medical departments. Adherence to clinical guideline development was investigated using the AGREE II instrument...
Sun Sep 20, 2020 03:00
Publication date: Available online 17 September 2020Source: Dental MaterialsAuthor(s): Gabriel Felipe Bragança, Arthur Silva Vianna, Flávio Domingues Neves, Richard Bengt Price, Carlos José Soares
Fri Sep 18, 2020 21:01
Publication date: Available online 18 September 2020Source: Dental MaterialsAuthor(s): W. Yan, H. Chen, J. Fernandez-Arteaga, A. Paranjpe, H. Zhang, D. Arola
Sat Sep 19, 2020 15:05
Publication date: Available online 19 September 2020Source: Dental MaterialsAuthor(s): Ranulfo Benedito de Paula Miranda, Tayná Paula Leite, Ana Clara Fagundes Pedroni, Márcia Martins Marques, Nelson Batista de Lima, Juliana Marchi, Paulo Francisco Cesar
Sat Sep 19, 2020 15:05
Publication date: Available online 19 September 2020Source: Dental MaterialsAuthor(s): Sonaj Vardhaman, Marcia Borba, Marina R. Kaizer, DoKyung Kim, Yu Zhang
Sat Sep 19, 2020 15:05
Publication date: Available online 19 September 2020Source: Dental MaterialsAuthor(s): Chih-Chieh Huang, Ming-Jun Li, Pei-I Tsai, Pei-Ching Kung, San-Yuan Chen, Jui-Sheng Sun, Nien-Ti Tsou
00:05
Publication date: Available online 19 September 2020Source: Magnetic Resonance ImagingAuthor(s): Yan Wu, Debiao Li, Lei Xing, Garry Gold
Sat Sep 19, 2020 13:50
Publication date: Available online 19 September 2020Source: Magnetic Resonance ImagingAuthor(s): P.K. Bhattacharyya, M.J. Lowe, K.E. Sakaie, H. Li, J. Lin, R.J. Fox
Sat Sep 19, 2020 13:50
Publication date: Available online 19 September 2020Source: Magnetic Resonance ImagingAuthor(s): Yan Li, Sagar Buch, Naying He, Chencheng Zhang, Yingying Zhang, Tao Wang, Dianyou Li, Ewart Mark Haacke, Fuhua Yan
00:32
Ankylosing spondylitis is a chronic inflammatory bone disease that commonly affects the spine and the sacroiliac joints. Ankylosing spondylitis can also cause enthesitis, or enthesopathy, which is an inflammation at the tendinous or ligamentous insertion sites on the bones. In this study, we present the case of a 37-year-old man with ankylosing spondylitis with a unique 99mTc-HDP bone scan finding of symmetrical increased uptake bilaterally in the greater trochanters. Received for publication April...
Wed Sep 16, 2020 03:00
Testicular metastasis is rare, with prostate cancer followed by lung cancer being the commonest primary site. Usually these are incidentally detected and are rarely symptomatic. We present an unusual case of adenocarcinoma lung, presenting initially with right testicular pain. Further workup with 18F-FDG PET/CT demonstrated primary malignancy of the left lung with nodal and right testicular metastasis. Received for publication July 18, 2020; revision accepted August 4, 2020. Conflicts of...
Wed Sep 16, 2020 03:00
A 69-year-old woman with multiple myeloma came to our department for 18F-FDG PET/CT scan for routine surveillance. The patient denied any history of fever, cough, shortness of breath, or body aches. 18F-FDG PET/CT scan from vertex to knees was performed. PET/CT images revealed extensive peripheral ground-glass opacities showing intense FDG uptake (SUVmax 12) involving bilateral lower lobes. Possibility of an infective etiology including novel coronavirus (COVID-19) infection was raised. The patient’s...
Wed Sep 16, 2020 03:00
Background The presence of visceral metastases is associated with poor prognosis in patients of metastatic castration-resistant prostate cancer (mCRPC) treated with hormonal therapy and chemotherapy. However, studies evaluating its impact on treatment outcomes with 177Lu-labeled prostate-specific membrane antigen (PSMA) radioligand therapy (RLT) are currently limited and show inconsistent results. This systematic review was conducted to precisely evaluate the impact of visceral metastases on...
Wed Sep 16, 2020 03:00
We present a 42-year-old woman with primary central nervous system lymphoma (PCNSL) and strong 18F-FDOPA PET uptake. 18F-FDOPA PET has high diagnostic accuracy in gliomas and brain metastases. The L-type amino acid transporter 1, targeted by 18F-FDOPA and 11C-MET PET, is a cell-type transporter usually upregulated in malignant tumors, including PCNSL. In this line, strong uptake was already shown with 11C-MET in PCNSL. We report the same findings with 18F-FDOPA. Consequently, PCNSL is a possible...
Wed Sep 16, 2020 03:00
A 68-year-old man with a history of prostate cancer post–primary treatment presented with rising prostate-specific antigen levels and was referred for 18F-fluciclovine PET/MRI to localize recurrent disease. PET/MRI revealed a solitary focus of uptake in a soft tissue nodule in the anterior mediastinum, which was resected and found to be a type B2 thymoma. 18F-fluciclovine uptake is mediated by amino acid transporters, primarily alanine-serine-cysteine transporter 2 and L-type amino acid transporter...
Wed Sep 16, 2020 03:00
We describe the case of a 54-year-old woman, previously submitted to nephrectomy for sarcomatoid renal cell carcinoma and treated with antibiotics because of central venous catheter infection. An 18F-FDG PET/CT scan was obtained that demonstrated bone and lymph node metastases and also disclosed an irregular area of highly increased uptake (SUVmax 19.4) in the right atrium. Clinical data did not suggest a relapsed infection. A contrast-enhanced CT examination of the heart enabled the diagnosis of...
Wed Sep 16, 2020 03:00
Acquired pulmonary stenosis in adults is rare and is usually caused by extrinsic compression from a mediastinal tumor. We present a case of anterior mediastinal Hodgkin lymphoma, who presented with cough and hemoptysis. Compression of the bilateral pulmonary arteries by the mediastinal mass was demonstrated by transthoracic echocardiography and CT pulmonary angiography. FDG PET/CT showed diffusely increased FDG uptake in right ventricular myocardium in addition to lymphomatous involvement of the...
Wed Sep 16, 2020 03:00
Extrarenal Wilms tumor (ERWT) is an extremely rare neoplasm of childhood. It occurs predominantly in retroperitoneum and pelvic or inguinal region without involvement of the kidneys. Although the importance of FDG PET/CT in Wilms tumor is well known, its use in ERWT is limited. Herein, we present FDG PET/CT findings of a 3-year-old girl with a lumbar mass, which was later diagnosed with ERWT. Received for publication July 24, 2020; revision accepted August 9, 2020. Conflicts of interest and...
Wed Sep 16, 2020 03:00
Osteoradionecrosis (ORN) is a well-documented complication following radiation treatment for head and neck malignancy. Facial bones, mainly the mandible, laryngeal cartilage, and skull, are frequently involved sites for ORN. A rare site for ORN is the hyoid, with very limited cases described in the literature. Recognition of the imaging pattern of hyoid ORN is critical to avoid misdiagnosis of recurrent disease, prompting early treatment. Received for publication April 21, 2020; revision accepted...
Wed Sep 16, 2020 03:00
A 21-year-old man with NF1 (neurofibromatosis type 1) mutation and in remission from acute myeloid leukemia presented with a painless mass in the left upper limb. MRI showed a soft-tissue mass involving the ulnar nerve presumed to be a nerve sheath tumor. 18F-FDG PET/CT was performed demonstrating high FDG avidity in the mass, prompting a biopsy. Histopathology and immunohistochemistry of the biopsy sample demonstrated myeloid sarcoma of the ulnar nerve. This case highlights the role of 18F-FDG PET/CT...
Wed Sep 16, 2020 03:00
A patient with moderately differentiated pancreatic neuroendocrine tumor with synchronous multifocal liver metastases was referred for further staging with PET/CT. The examinations were performed on 2 consecutive days and showed mild 68Ga-DOTANOC and intense 18F-FDG uptake in an incidental right parotid nodule. Differential diagnoses include primary or metastatic neuroendocrine tumor, malignant or benign primary parotid tumor, and intraparotid lymph node. Histology revealed characteristics of a Warthin...
Wed Sep 16, 2020 03:00
18F-Fluorocholine (18F-FCH) PET/CT is widely used to study patients affected by prostate cancer. 18F-FCH PET/CT is suitable for the detection of pelvic and abdominal nodal and skeletal metastases. Indeed, 18F-FCH PET/CT sensitivity for other organs, such as the liver and the urinary tract, is lowered by the radiopharmaceutical urinary washout and intense liver uptake. Herein, we report the case of a patient affected by oligometastatic prostate cancer in good clinical condition treated with total...
Wed Sep 16, 2020 03:00
A 43-year-old woman presented with numbness of the left hand and leg for 4 weeks. MRI of the spinal cord revealed an intramedullary lesion with central nodular enhancement at the C3 level. Primary tumor or metastasis of the cervical spinal cord was suspected. FDG PET/CT showed focal hypermetabolism of the spinal cord corresponding to the gadolinium-enhanced nodule. The patient underwent resection of the cervical spinal cord lesion. Histopathological findings of the resected specimens were consistent...
Wed Sep 16, 2020 03:00
Lung scintigraphy was performed to rule out pulmonary embolism in a 37-year-old woman suffering from dyspnea and hypoxemia after routine diagnostics failed to find the underlying disease. Perfusion scans did not show tracer uptake within the lungs despite ventilation scans being unremarkable. Instead, the result suggested a complete right-to-left shunt, which was a conundrum. With the assistance of CT an uncommon congenital vessel aberration turned out to be the cause of this exceptional scintigraphy...
Wed Sep 16, 2020 03:00
Purpose Neuropsychiatric symptoms are important and frequent nonmotor features in Parkinson disease (PD). We explored mild behavioral impairment (MBI) in drug-naive patients with PD and its clinical and dopamine transporter (DAT) correlates. Methods We recruited 275 drug-naive patients with PD who had undergone Unified Parkinson’s Disease Rating Scale, a neuropsychological battery, Neuropsychiatric Inventory, and N-(3-[18F]fluoropropyl)-2β-carbon ethoxy-3β-(4-iodophenyl) PET within...
Wed Sep 16, 2020 03:00
Splenic metastasis from endometrial carcinoma is rare, especially when the spleen is the sole metastatic site. Herein, we report the case of a 47-year-old woman with a history of endometrial adenocarcinoma diagnosed 1 year ago. At that time, she underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, and pelvic node dissection. Restaging 18F-FDG PET/CT demonstrated an isolated splenic mass with elevated FDG activity. There were no other signs of recurrence. The lesion was surgically...
Wed Sep 16, 2020 03:00
Spinal facet joint septic arthritis is a rare pathology associated with pyogenic organisms. It may present in older adults with back pain, fever, and positive bacterial blood cultures. However, clinical presentation may be equivocal, and diagnosis relies on anatomic imaging for differentiation from other pathologies. Magnetic resonance is considered the imaging modality of choice and has been found superior to CT; however, it is unable to differentiate facet joint septic arthritis from other inflammatory...
Wed Sep 16, 2020 03:00
Cardiac metastases are an infrequent site of metastasis in neuroendocrine tumors, and the treatment implications in the era of peptide receptor radionucleotide therapy (PRRT) are unclear. Potential safety concerns exist regarding cardiac integrity and function in response to PRRT. We describe our institutional experience with 4 patients with well-differentiated, midgut neuroendocrine tumors with cardiac involvement detected on 68Ga-DOTATATE PET/CT scans who were treated with PRRT. Received for...
Wed Sep 16, 2020 03:00
No abstract available
Wed Sep 16, 2020 03:00
A 60-year-old man with prostate adenocarcinoma status post radical prostatectomy and bilateral pelvic lymph node dissection referred for restaging 18F-fluciclovine PET/CT due to rising serum prostate-specific antigen levels (1.1 ng/mL at that time of imaging). PET/CT images were obtained from the proximal thighs to the vertex of the skull approximately 3 to 5 minutes after the IV administration of 347.8 MBq (9.4 mCi) of 18F-fluciclovine. PET/CT imaging demonstrated a focus of abnormally increased...
Wed Sep 16, 2020 03:00
Adrenal Castleman disease is very rare. We reported image findings of a right adrenal mass in a 75-year-old man on 99mTc-HYNIC-TOC scan and FDG PET/CT. There was obviously elevated 99mTc-HYNIC-TOC activity, but the intensity of FDG activity was remarkable. Pheochromocytoma was initially suspected. However, pathology from resected specimen showed adrenal Castleman disease. Received for publication July 16, 2020; revision accepted July 23, 2020. Conflicts of interest and sources of funding:...
Wed Sep 16, 2020 03:00
68Ga–prostate-specific membrane antigen (68Ga-PSMA) PET/CT has shown excellent results in imaging of prostate cancer. Some nonprostatic malignancies can also demonstrate 68Ga-PSMA uptake, including primary lung adenocarcinoma. However, no such data are present for small cell lung cancer. We present the case of a 59-year-old man, where a second primary metastatic small cell lung cancer was discovered on 68Ga-PSMA PET/CT done for suspected recurrence of prostate cancer. Received for publication...
Wed Sep 16, 2020 03:00
Hyalinizing cholecystitis is a rare type of chronic cholecystitis. Moderate patchy transmural especially perivascular lymphoplasmacytic inflammatory cell infiltration is observed in the gallbladder wall. We present the 18F-FDG PET/CT and MRI findings of this rare subtype of chronic cholecystitis. Hyalinizing cholecystitis should be kept in mind in the differential diagnosis of gallbladder wall thickening with intense 18F-FDG uptake. Received for publication July 12, 2020; revision accepted July...
Wed Sep 16, 2020 03:00
Abstract Streptococcus suis (S. suis) is an important zoonotic agent, which seriously impacts the pig industry and human health in various countries. Biofilm formation is likely contributing to the virulence and drug resistance in S. suis. A better knowledge of biofilm formation as well as to biofilm-dependent drug resistance mechanisms in S. suis can be of great significance for the prevention and treatment of S. suis infections. This literature review updates the latest scientific...
03:39
Abstract Photoautotrophic microalgae offer a great potential as novel hosts for efficient recombinant protein production. Nannochloropsis oceanica produces an extraordinarily high content of polyunsaturated fatty acids, and its robust growth characteristics, published genome sequence and efficient nuclear transformation make N. oceanica a promising candidate for biotechnological applications. To establish a robust and flexible system for recombinant...
03:39
Abstract Bacteria belonging to Rhodococcus genus represent ideal candidates for microbial biotechnology applications because of their metabolic versatility, ability to degrade a wide range of organic compounds, and resistance to various stress conditions, such as metal toxicity, desiccation, and high concentration of organic solvents. Rhodococcus spp. strains have also peculiar biosynthetic activities that contribute to their strong persistence in harsh...
03:39
Correction to: Indian sarsaparilla, Hemidesmus indicus (L.) R. Br. ex Schult: tissue culture studies
Following publication of the original article (Kher et al. 2020), the authors identified following mistake in the author affiliation.
03:39
Abstract Pseudomonas aeruginosa biofilms contribute heavily to chronic lung infection in cystic fibrosis patients, leading to morbidity and mortality. Nitric oxide (NO) has been shown to disperse P. aeruginosa biofilms in vitro, ex vivo and in clinical trials as a promising anti-biofilm agent. Traditional NO donors such as sodium nitroprusside (SNP) have been extensively employed in different studies. However, the dosage of SNP in different studies...
03:39
In the original publication of the article, it was published under the title ‘Applied microbiology and biotechnology uncovering the biosynthetic pathway of polysaccharide-based microbial flocculant in Agrobacterium tumefaciens F2’.
03:39
Abstract Dunaliella salina (D. salina) has been widely applied in various fields because of its inherent advantages, such as the study of halotolerant mechanism, wastewater treatment, recombinant proteins expression, biofuel production, preparation of natural materials, and others. However, owing to the existence of low yield or in the laboratory exploration stage, D. salina system has been greatly restricted for practical production of various components....
03:39
AbstractAggressive angiomyxoma is a rare mesenchymal tumor occurring usually in women of reproductive age in pelvic-perineum region. These myofibroblastic tumors rarely affect men and non-pelvic-perineum anatomical sites. There are few literature references for aggressive angiomyxoma in men. We describe a case of a 57-year old male with aggressive angiomyxoma of the scrotum and its management.
Fri Sep 18, 2020 03:00
AbstractThe purpose of this paper is to report unusual, rarest and interesting case of a patient with nodular hyperplasia of Bartholin's gland with dysplastic changes. The case of a 30-year old female with right-sided Bartholin’s gland hyperplasia with dysplastic changes, which was confirmed histopathologically, is presented in this paper. The patient reported increased swelling of the right major labium when she became sexually aroused with intermittent dyspareunia during intercourse. Surgical excision...
Fri Sep 18, 2020 03:00
AbstractNeuroendocrine neoplasms are rare malignancies, more so when cancerous metastasis occurs without a known primary source. Here we discuss a case of an ulcerative colitis sufferer, 43-year-old lady presented with what was thought to be a flare up. Situation deteriorated and was taken to theatre to find a significantly ischaemic colon, secondary to extensive venous thrombosis. The ischaemic bowel was resected alongside with what was thought to be a large, reactive lymph node. To our surprise,...
Sat Sep 19, 2020 03:00
AbstractWe report the case of a patient with duplication of the inferior vena cava (DIVC) who underwent anterior laparoscopic resection for rectal cancer. A 66-year-old woman presented with abnormal lung shadows on a chest x-ray during a routine health checkup. She was diagnosed with rectal cancer and lung metastasis using colonoscopy and thoracoabdominal computed tomography (CT). In addition, a 3D CT angiography revealed double inferior vena cava, one on either side of the aorta. The preoperative...
03:00
To describe the impact of research, beyond the limits of the academic environment, Altmetric, a new social and traditional media metric was proposed. The aims of this study were to analyze the online activity ...
03:00
The Central Highland Plateau of Madagascar is largely composed of grassland savanna, interspersed with patches of closed-canopy forest. Conventional wisdom has it that these grasslands are anthropogenic in nature, having been created very recently via human agricultural practices. Yet, the ancient origins of the endemic grasses suggest that the extensive savannas are natural biomes, similar to others found around the globe. We use a phylogeographic approach to compare these two competing scenarios....
Fri Sep 18, 2020 03:00
Studies in a variety of species have shown evidence for positively selected variants introduced into one population via introgression from another, distantly related population--a process known as adaptive introgression. However, there are few explicit frameworks for jointly modelling introgression and positive selection, in order to detect these variants using genomic sequence data. Here, we develop an approach based on convolutional neural networks (CNNs). CNNs do not require the specification...
Sun Sep 20, 2020 03:00
Discrepancies in mitochondrial and nuclear genetic data are often interpreted as evidence of hybridisation. We re-examined reports of hybridisation in three cryptic stingless bee species in the genus Tetragonula in South East Queensland, Australia (T. carbonaria, T. davenporti, and T. hockingsi). Previous studies on this group using microsatellite markers proposed that occasional hybrids are found. In contrast, we find that allele frequencies at neutral regions of the nuclear genome, both microsatellites...
Fri Sep 18, 2020 03:00
Closely related species that have previously inhabited geographically separated ranges are hybridizing at an increasing rate due to human disruptions. These anthropogenic hybrid zones can be used to study reproductive isolation between species at secondary contact, including examining locus-specific rates of introgression. Introgression is expected to be heterogenous across the genome, reflecting variation in selection. Those loci that introgress especially slowly are good candidates for being involved...
Fri Sep 18, 2020 03:00
Heteroplasmy is the coexistence of more than one type of mitochondria in an organism. Although widespread sequencing has identified several cases of transient or low-level heteroplasmy that primarily occur through mutation or paternal leakage, stable, high-titer heteroplasmy remains rare in animals. In this study we present a unique, stable and high-level heteroplasmy in male and female flies belonging to the neotropical Drosophila paulistorum species complex. We show that mitochondria of D. paulistorum...
Fri Sep 18, 2020 03:00
Setosphaeria turcica is a major fungal pathogen of maize and causes the foliar disease Northern corn leaf blight (NCLB). It originates from tropical regions and expanded into Central Europe since the 1980s, simultaneously with a rapid increase of maize cultivation area in this region. To investigate evolutionary processes influencing the rapid expansion of S. turcica we sequenced 121 isolates from Central Europe, Western Europe and Kenya. Population genetic inference revealed five genetically distinct...
Fri Sep 18, 2020 03:00
Every species experiences limits to its geographic distribution. Some evolutionary models predict that populations at range edges are less well-adapted to their local environments due to drift, expansion load, or swamping gene flow from the range interior. Alternatively, populations near range edges might be uniquely adapted to marginal environments. In this study, we use a database of transplant studies that quantify performance at broad geographic scales to test how local adaptation, site quality,...
Sun Sep 20, 2020 03:00
Transparency reduces prey detectability by predators. While the proportion of transmitted light in aquatic species is higher as light availability increases, less is known about such variation in terrestrial species. Transparency has evolved several times in the typically opaque winged Lepidoptera order (moths and butterflies), displaying a large diversity of degrees. Using two complementary approaches, we explore how the evolution of the differences in light transmittance relates to habitat openness,...
Fri Sep 18, 2020 03:00
Human centromeres form over arrays of tandemly repeated DNA that are exceptionally complex (repeats of repeats) and long (spanning up to 8 Mbp). They also have an exceptionally rapid rate of evolution. The generally accepted model for the expansion/contraction, homogenization and evolution of human centromeric repeat arrays is a generic model for the evolution of satellite DNA that is based on unequal crossing over between sister chromatids. This selectively neutral model predicts that the sequences...
Sat Sep 19, 2020 03:00
Computational analyses of pathogen genomes are increasingly used to unravel the dispersal history and transmission dynamics of epidemics. Here, we show how to go beyond historical reconstructions and use spatially-explicit phylogeographic and phylodynamic approaches to formally test epidemiological hypotheses. We illustrate our approach by focusing on the West Nile virus (WNV) spread in North America that has been responsible for substantial impacts on public, veterinary, and wildlife health. WNV...
Sat Sep 19, 2020 03:00
Landmark-based geometric morphometrics has emerged as an essential discipline for the quantitative analysis of size and shape in ecology and evolution. With the ever-increasing density of digitized landmarks, the possible development of a fully automated method of landmark placement has attracted considerable attention. Despite the recent progress in image registration techniques, which could provide a pathway to automation, three-dimensional morphometric data is still mainly gathered by trained...
Sat Sep 19, 2020 03:00
Interspecific crossing experiments have shown that sex chromosomes play a major role in the reproductive isolation of many species. However, their ability to act as reproductive barriers, which hamper interspecific genetic exchange, has rarely been evaluated quantitatively compared to autosomes. However, this genome-wide limitation of gene flow is essential for understanding the complete separation of species, and thus speciation. Here, we develop a mainland-island model of secondary contact between...
Sun Sep 20, 2020 03:00
Biased mutation spectra are pervasive, with widely varying direction and magnitude of mutational bias. Why are unbiased spectra rare, and how do such diverse biases evolve? We find that experimentally changing the mutation spectrum increases the beneficial mutation supply, because populations sample mutational classes that were poorly explored by the ancestor. Simulations show that selection does not oppose the evolution of a mutational bias in an unbiased ancestor; but it favours changing the direction...
Sun Sep 20, 2020 03:00
Fluctuating environmental pressures can challenge organisms by repeatedly shifting the optimum phenotype. Two contrasting evolutionary strategies to cope with these fluctuations are 1) evolution of the mean phenotype to follow the optimum (adaptive tracking) or 2) diversifying phenotypes so that at least some individuals have high fitness in the current fluctuation (bet-hedging). Bet-hedging could underlie stable differences in the behavior of individuals that are present even when genotype and environment...
Sun Sep 20, 2020 03:00
Dietary patterns have long been a driver of global land use. Increasingly, they also respond to it, in part because of social forces that support adoption of sustainable diets. Here we develop a coupled social-land use dynamics model parameterised for 164 countries. We project global land use under 20 scenarios for future population, income, and agricultural yield. When future yields are low and/or population size is high, coupled social-land feedbacks can reduce the peak global land use by up to...
Sun Sep 20, 2020 03:00
Are daughters of older mothers less fertile? The human mutation rate is high and increases with chronological age. As female oocytes age, they become less functional, reducing female chances at successful reproduction. Increased oocyte mutation loads at advanced age may be passed on to offspring, decreasing fertility among daughters born to older mothers. In this paper we study the effects of maternal ageing on her daughter's fertility, including total number of children, age at last birth, and neonatal...
Sun Sep 20, 2020 03:00
Independent origins of sociality in bees and ants are associated with independent expansions of the odorant receptor (OR) gene family. In ants, one clade within the OR gene family, the 9-exon subfamily, has dramatically expanded. These receptors detect cuticular hydrocarbons (CHCs), key social signaling molecules in insects. It is unclear to what extent 9-exon OR subfamily expansion is associated with the independent evolution of sociality across Hymenoptera, warranting studies of taxa with independently...
Sun Sep 20, 2020 03:00
Exchanging genetic material with another individual seems risky from an evolutionary standpoint, and yet living things across all scales and phyla do so quite regularly. The pervasiveness of such genetic exchange, or recombination, in nature has defied explanation since the time of Darwin. Conditions that favor recombination, however, are well-understood: recombination is advantageous when the genomes of individuals in a population contain more selectively mismatched combinations of alleles than...
Sun Sep 20, 2020 03:00
Authors: Arwa Lachkhem, Ibtissem Lahmar, Lokman Galal, Oussama Babba, Habib Mezhoud, Mohssen Hassine, Ahmed Lachkhem, Marie-Laure Dardé, Aurélien Mercier and Hamouda Babba.<br />Parasite Vol. 27 , page 51<br />Published online: 21/09/2020<br /> Keywords: Toxoplasma gondii ; Blood donors ; Seroprevalence ; Risk factors ; Tunisia.<img src="http://feeds.feedburner.com/~r/edp_parasite/~4/8p9_SGYt-54" height="1" width="1" alt=""/>
03:00
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.