American Journal of Anatomy最新文献

{"title":"The Role of Foveal Cortex in Discriminating Peripheral Stimuli: The Sketchpad Hypothesis.","authors":"Carolina Maria Oletto, Giulio Contemori, Marco Bertamini, Luca Battaglini","doi":"10.3390/neurosci4010002","DOIUrl":"10.3390/neurosci4010002","url":null,"abstract":"<p><p>Foveal (central) and peripheral vision are strongly interconnected to provide an integrated experience of the world around us. Recently, it has been suggested that there is a feedback mechanism that links foveal and peripheral vision. This peripheral-to-foveal feedback differs from other feedback mechanisms in that during visual processing a novel representation of a stimulus is formed in a different cortical region than that of the feedforward representation. The functional role of foveal feedback is not yet completely understood, but some evidence from neuroimaging studies suggests a link with peripheral shape processing. Behavioural and transcranial magnetic stimulation studies show impairment in peripheral shape discrimination when the foveal retinotopic cortex is disrupted post stimulus presentation. This review aims to link these findings to the visual sketchpad hypothesis. According to this hypothesis, foveal retinotopic cortex stores task-relevant information to aid identification of peripherally presented objects. We discuss how the characteristics of foveal feedback support this hypothesis and rule out other possible explanations. We also discuss the possibility that the foveal feedback may be independent of the sensory modality of the stimulation.</p>","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"39 1","pages":"9-17"},"PeriodicalIF":1.6,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11523757/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73024950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association of Lymphovascular Space Invasion With Locoregional Failure and Survival in Patients With Node-Negative Oral Tongue Cancers.","authors":"Richard J Cassidy, Jeffrey M Switchenko, Naresh Jegadeesh, Mutlay Sayan, Matthew J Ferris, Bree R Eaton, Kristin A Higgins, Jeffrey T Wadsworth, Kelly R Magliocca, Nabil F Saba, Jonathan J Beitler","doi":"10.1001/jamaoto.2016.3795","DOIUrl":"10.1001/jamaoto.2016.3795","url":null,"abstract":"<p><strong>Importance: </strong>The indications for adjuvant therapy in resected oral tongue cancers are based on both clinical and pathological factors, with clear evidence for adjuvant radiation in patients with pathologically positive neck lymph nodes, positive margins, and extracapsular extension, but the data for patients with no nodal disease are sparse.</p><p><strong>Objective: </strong>To investigate determinants of failure and survival in patients with node-negative oral tongue cancer.</p><p><strong>Design, setting, and participants: </strong>Medical records for patients with oral tongue cancer treated with definitive surgery from 2003 to 2013 were reviewed. All patients were cN0 negative and classified as pathologically node-negative (pN0) if a neck dissection was performed. Patients received adjuvant radiotherapy (RT) or chemoradiotherapy (CRT) based on standard clinical and pathological determinants.</p><p><strong>Main outcomes and measures: </strong>Kaplan-Meier and multivariable (MVA) logistic regression and Cox proportional hazard regression analyses were performed to identify patient, tumor, and treatment characteristics predictive of locoregional control (LRC) and overall survival (OS).</p><p><strong>Results: </strong>A total of 180 patients met entry criteria, with a median follow-up time of 4.9 years (range, 0.9-12.5 years); 102 patients (56.7%) were female and 42 patients (23.3%) were younger than 45 years at diagnosis. One hundred fifty-three patients (85%) had T1/T2 tumors, and 112 patients (62%) had elective neck dissections with confirmed pN0. Lymphovascular space invasion (LVSI) was present in 36 patients (20%). On MVA, LVSI (OR, 0.06; 95% CI, 0.02-0.19; P < .01) was associated with worse LRC. Elective neck dissection (odds ratio [OR], 2.99; 95% CI, 1.16-7.73; P = .02) and receipt of RT (OR, 7.74; 95% CI, 2.27-26.42; P < .01) were associated with improved LRC. Three-year LRC rates were significantly lower for patients with LVSI (38.8%; 95% CI, 22.8%, 54.6%) than those without LVSI (81.9%; 95% CI, 74.4%, 87.4%). On MVA, only LVSI (hazard ratio, 2.20; 95% CI, 1.19-4.06; P = .01) and age greater than 44 years (hazard ratio, 4.38; 95% CI, 1.34-14.27; P = .01) were associated with worse OS. Three-year OS rates were significantly lower in patients with LVSI (71.3%; 95% CI, 53.2%-83.4%) than those without LVSI (90.3%; 95% CI, 83.8%-94.3%).</p><p><strong>Conclusions and relevance: </strong>Lymphovascular space invasion in patients with node-negative oral tongue cancer treated with upfront definitive surgery is associated with worse LRC and OS. Node-negative oral cavity cancers with LVSI warrant consideration of further adjuvant therapy, which should be further evaluated in a prospective setting.</p>","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"31 1","pages":"382-388"},"PeriodicalIF":7.8,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5398912/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73016708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trimethylamine N-Oxide and Mortality Risk in Patients With Peripheral Artery Disease.","authors":"Vichai Senthong, Zeneng Wang, Yiying Fan, Yuping Wu, Stanley L Hazen, W H Wilson Tang","doi":"10.1161/JAHA.116.004237","DOIUrl":"10.1161/JAHA.116.004237","url":null,"abstract":"<p><strong>Background: </strong>Production of the proatherogenic metabolite, trimethylamine N-oxide (TMAO), from dietary nutrients by intestinal microbiota enhances atherosclerosis development in animal models and is associated with atherosclerotic coronary artery disease in humans. The utility of studying plasma levels of TMAO to risk stratify in patients with peripheral artery disease (PAD) has not been reported.</p><p><strong>Methods and results: </strong>We examined the relationship between fasting plasma TMAO and all-cause mortality (5-year), stratified by subtypes of PAD and presence of coronary artery disease in 935 patients with PAD who underwent elective angiography for cardiac evaluation at a tertiary care hospital. Median plasma TMAO was 4.8 μmol/L (interquartile range, 2.9-8.0 μmol/L). Elevated TMAO levels were associated with 2.7-fold increased mortality risk (fourth versus first quartiles, hazard ratio 2.86, 95% CI 1.82-3.97, P<0.001). Following adjustments for traditional risk factors, inflammatory biomarkers, and history of coronary artery disease, the highest TMAO quartile remained predictive of 5-year mortality (adjusted hazard ratio 2.06, 95% CI 1.36-3.11, P<0.001). Similar prognostic value for elevated TMAO was seen for subjects with carotid artery, non-carotid artery, or lower extremity PAD. TMAO provided incremental prognostic value for all-cause mortality (net reclassification index, 40.22%; P<0.001) and improvement in area under receiver operator characteristic curve (65.7% versus 69.4%; P=0.013).</p><p><strong>Conclusions: </strong>TMAO, a pro-atherogenic metabolite formed by gut microbes, predicts long-term adverse event risk and incremental prognostic value in patients with PAD. These findings point to the potential for TMAO to help improve selection of high-risk PAD patients with or without significant coronary artery disease, who likely need more aggressive and specific dietary and pharmacologic therapy.</p>","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1161/JAHA.116.004237","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73007087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study of the nucleus in the normal and hyperplastic liver of the rat","authors":"N. M. Sulkin","doi":"10.1002/AJA.1000730106","DOIUrl":"https://doi.org/10.1002/AJA.1000730106","url":null,"abstract":"","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"73 1","pages":"107-125"},"PeriodicalIF":0.0,"publicationDate":"2005-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/AJA.1000730106","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51434636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proliferation in the genital tract of the normal mature guinea pig treated with colchicine","authors":"I. G. Schmidt","doi":"10.1002/AJA.1000730104","DOIUrl":"https://doi.org/10.1002/AJA.1000730104","url":null,"abstract":"","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"73 1","pages":"59-80"},"PeriodicalIF":0.0,"publicationDate":"2005-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/AJA.1000730104","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51434530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Liver extirpation and implantation in Amblystoma embryos with particular reference to blood formation","authors":"W. Copenhaver","doi":"10.1002/AJA.1000730105","DOIUrl":"https://doi.org/10.1002/AJA.1000730105","url":null,"abstract":"","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"1 1","pages":"81-105"},"PeriodicalIF":0.0,"publicationDate":"2005-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/AJA.1000730105","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51434597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scleral calcification and photoreceptor cell death during aging and exposure to chronic stress.","authors":"W K O'Steen,&nbsp;A Brodish","doi":"10.1002/aja.1001890108","DOIUrl":"https://doi.org/10.1002/aja.1001890108","url":null,"abstract":"<p><p>Male and female Fischer 344 rats of three different ages (12, 18, and 25 months) have been examined for the presence of photoreceptor (PR) cell loss and for occurrence of scleral cartilage and bone formation. In addition, male and female rats, aged 11 months at the beginning of the experiments, were exposed to chronic stress for either 0.5, 2, 4, or 6 months. Photoreceptor cell death gradually increases during the aging process and is exacerbated by exposure to chronic stress. It is more severe in the peripheral than the central retina and exposure to stress increases this pattern of cell loss. The superior retina is more severely affected than the inferior hemisphere in aging and during stress. The incidence of scleral cartilage or bone formation increases with age in male and female rats, but with stress exposure an increase is seen in males only. Bone formations occur more frequently in male than in female animals and are almost always (97%) located in the superior hemisphere of the eye. Although there appears to be a direct relationship between photoreceptor cell death and the occurrence of scleral ossifications in group data, in individual eyes the bone formations are not always associated with severity of PR cell loss. The relationship of PR cell death and incidence of scleral ossification to gender and to exposure to stress supports a hypothesis for an endocrine basis of ocular aging.</p>","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"189 1","pages":"62-8"},"PeriodicalIF":0.0,"publicationDate":"1990-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/aja.1001890108","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13391849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A morphologic study of bronchus-associated lymphoid tissue in turkeys.","authors":"J A Fagerland,&nbsp;L H Arp","doi":"10.1002/aja.1001890104","DOIUrl":"https://doi.org/10.1002/aja.1001890104","url":null,"abstract":"<p><p>Bronchus-associated lymphoid tissue (BALT) in normal turkeys of ages 1 day and 1, 2, 3, 4, 8, and 18 weeks was examined by light microscopy and by scanning and transmission electron microscopy. Turkey BALT resembled other mucosa-associated lymphoid tissues; it was made up of a population of lymphocytes covered by a specialized epithelium different from typical pseudostratified ciliated columnar bronchial epithelium. There were distinct age-related differences in BALT structure. Bronchus-associated lymphoid nodules were larger and more numerous in older turkeys. In 1-day- to 2-week-old turkeys, the primary cell type of BALT epithelium was nonciliated cuboidal; in 2-week old turkeys it was squamous; and in turkeys older than 4-weeks of age, the epithelium was primarily ciliated columnar. In 1- to 4-week old turkeys, large numbers of intraepithelial lymphocytes disrupted the normal organization of the epithelium. In older turkeys, epithelial and lymphoid cells were in discrete compartments separated by connective tissue. Lymphocytes in 1-day-old turkeys were found in loose aggregates around venules and within the epithelium. In 1-week old turkeys, lymphocytes were organized into compartments of morphologically similar cells. By 3-weeks of age, lymphocytes were present in distinct germinal centers. Epithelial cells of BALT did not have large numbers of apical vesicles and thus were not structurally specialized for antigen uptake by endocytosis. However, the epithelial barrier appeared to be disrupted over lymphoid nodules, suggesting that antigen would be readily available to lymphocytes and phagocytes in BALT. Age-related differences in turkey BALT structure may have functional consequences with respect to the respiratory immune response.</p>","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"189 1","pages":"24-34"},"PeriodicalIF":0.0,"publicationDate":"1990-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/aja.1001890104","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13391845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three structures associated with the nucleolus in male rat germinal cells: round body, coiled body, and \"nubecula\" and general presence of round body at male meiosis.","authors":"M C Schultz","doi":"10.1002/aja.1001890103","DOIUrl":"https://doi.org/10.1002/aja.1001890103","url":null,"abstract":"<p><p>In addition to chromosomes and nucleoli, three structures, i.e., round body, coiled body, and nubecula, are encountered in the nucleus during the meiotic prophase in male rats. These structures have been examined by electron microscopy in random and serial sections. The round body is a finely fibrillar, proteinaceous structure closely associated with the granular component of a nucleolus in rat spermatocytes and young spermatids. A similar structure has been observed in man, the monkey Macaca mulatta, the gastropod Achatina fulica, and the insect Locusta migratoria. Together with evidence from the literature, these results support the view that the round body is of general occurrence in the male meiocytes of eukaryotes and may, therefore, play a role in meiosis. The coiled body is a group of electron-dense elements called \"coils\", which average 35 nm in width, except after mid-pachytene when their size almost doubles. The coils are composed of 2-nm-wide filaments and 8 to 10-nm-wide granules, both of which are ribonucleoprotein. The coiled bodies are interpreted to be groups of \"spliceosomes\", that is, structures containing heterogeneous RNA and small nuclear RNA. A remarkable feature of the coiled body is its temporary disappearance at early pachytene and its reappearance at late pachytene, possibly due to drastic changes in the turnover rate of its component RNAs. The nubecula is a newly identified nuclear inclusion, composed of weakly staining threads loosely organized into a 560 nm-wide spheroid. It has been observed only in early pachytene nuclei.</p>","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"189 1","pages":"11-23"},"PeriodicalIF":0.0,"publicationDate":"1990-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/aja.1001890103","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12864866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nucleolar structure and synthetic activity during meiotic prophase and spermiogenesis in the rat.","authors":"M C Schultz,&nbsp;C P Leblond","doi":"10.1002/aja.1001890102","DOIUrl":"https://doi.org/10.1002/aja.1001890102","url":null,"abstract":"<p><p>The ultrastructure of nucleoli was examined in developing rat spermatocytes and spermatids, with the help of serial sections. In addition, the radioautographic reaction of nucleoli as examined in rats sacrificed 1 hr after intratesticular injection of 3H(5')-uridine and taken as an index of the rate of synthesis of ribosomal RNA (rRNA). Primary spermatocytes from preleptotene to zygotene have small nucleoli typically composed of fibrillar centers, a fibrillar component, and a granular component, within which are narrow interstitial spaces. During early and mid-pachytene, nucleoli enlarge to about nine times their initial size, with the fibrillar and granular components forming an extensive network of cords--a nucleolonema--within which are wide interstitial spaces. Meanwhile, there appear structures identical to the granular component but distinct from nucleoli; they are referred to as extranucleolar granular elements. Finally, from late pachytene to the first maturation division, nucleoli undergo condensation, as shown by contraction of fibrillar centers into small clumps, while fibrillar and granular components condense and segregate from each other, with a gradual decrease in interstitial spaces. In secondary spermatocytes, nucleoli are compact and rather small, while in young spermatids they are also compact and even smaller. Nucleoli disappear in elongating spermatids. In 3H-uridine radioautographs, nucleolar label is weak in young primary spermatocytes, increases progressively during early pachytene, is strong by the end of mid pachytene, but gradually decreases during late pachytene up to the first maturation division. In secondary spermatocytes and spermatids, there is no significant nucleolar label. In conclusion, rRNA synthesis by nucleoli is low in young spermatocytes. During pachytene, while nucleoli enlarge and form a lacy nucleolonema, rRNA synthesis increases gradually to a high level by the end of mid pachytene. However, during the condensation and segregation of nucleolar components occurring from late pachytene onward, the synthesis gradually decreases and disappears. The small, compact spermatids arising from the second maturation division do not synthesize rRNA.</p>","PeriodicalId":50815,"journal":{"name":"American Journal of Anatomy","volume":"189 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"1990-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/aja.1001890102","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13391844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}