4,925 research outputs found
Gen Ed /
No full text"Gen Ed locates serious discussion of general education in the context of some of the day-to-day realities encountered in putting it into practice and promoting efforts at reform at Metropolitan Atlantic University (aka the Metro). This dual focus is found in the often-pugnacious policy debate among the faculty and a more light-hearted discussion of related questions carried on by Professor Kelly as he models Socratic teaching in his upper-level class for prospective teachers. Reforming general education at the Metro is not free of the vanities and vulgarities of ambitious men and women and self-serving politicians, of course, nor those who poke fun at them. Arnie Smatter, the irrepressible and nosey chat show host of Radio YOY ensures that this does not go unnoticed. The overall humorous tone of Gen Ed does not detract from Mulcahy's thoughtful treatment of substantive issues that will be of interest to serious scholars, students, and a general readership. It is the behaviour of those involved, the broader media and political contexts in which events take place, which mainly becomes the object of humorous treatment"--Includes bibliographical references and index.Preface -- Acknowledgements -- Chapter 1 -- Chapter 2 -- Chapter 3 -- Chapter 4 -- Chapter 5 -- Chapter 6 -- Chapter 7 -- Chapter 8 -- Chapter 9 -- Chapter 10 -- Chapter 11 -- Chapter 12 -- Chapter 13 -- Chapter 14 -- Chapter 15 -- Chapter 16 -- Chapter 17 -- Chapter 18 -- Chapter 19 -- Chapter 20 -- Appendix: Questions for Discussion, Suggested Topics for Term Papers and Research Projects -- References -- About the Author."Gen Ed locates serious discussion of general education in the context of some of the day-to-day realities encountered in putting it into practice and promoting efforts at reform at Metropolitan Atlantic University (aka the Metro). This dual focus is found in the often-pugnacious policy debate among the faculty and a more light-hearted discussion of related questions carried on by Professor Kelly as he models Socratic teaching in his upper-level class for prospective teachers. Reforming general education at the Metro is not free of the vanities and vulgarities of ambitious men and women and self-serving politicians, of course, nor those who poke fun at them. Arnie Smatter, the irrepressible and nosey chat show host of Radio YOY ensures that this does not go unnoticed. The overall humorous tone of Gen Ed does not detract from Mulcahy's thoughtful treatment of substantive issues that will be of interest to serious scholars, students, and a general readership. It is the behaviour of those involved, the broader media and political contexts in which events take place, which mainly becomes the object of humorous treatment"--Description based on print version record
The Embryonic Ascent of the Kidney Revisited
No full textABSTRACT Although the embryonic kidney's ascent is well established, the intermediate morphological changes that occur during the process are unclear. To evaluate the morphological events that accompany the kidney's ascent, we examined serial sagittal sections from 24 embryos at 5–7 weeks gestation. Six specimens had bilaterally ascending kidneys that were between the levels of the second to fifth lumbar vertebrae, and each kidney had a primitive renal cortex surrounding clusters of ampullae, which branched from the pelvis, and a dense tissue band that connected the renal cortex with the embryonic adrenal cortex or celiac ganglia, and there was no adipose capsule or renal artery. The tissue band contained abundant nerve twigs from the major splanchnic nerve; thus, it was conceivable that it was sufficiently rigid to support the length of the retroperitoneal tissue mass that included the embryonic adrenal cortex, celiac ganglia, and kidney. The lumbar vertebral body's height was much shorter than that of the ascending kidney. However, the lower vertebral column's curvature was often maintained, even when the kidneys had ascended. Therefore, vertebral column straightening was not the only factor required to drive the ascent. Together with the growth of the thorax and liver, the adrenal cortex, ganglia, and kidney appeared to change simultaneously at a position relative to the vertebrae. The renal artery established a connection to the renal cortex after the ascent. Evaluations of frontal sections from five additional specimens suggested that from its initial position, the kidney extended upwards between bilateral umbilical arteries. Anat Rec, 302:278–287, 2019. © 2018 The Authors. The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology published by Wiley Periodicals, Inc. on behalf of Wiley‐Liss, Inc
Left/right difference in the course and division of the pulmonary arterial branches in the lung upper lobe: A study using human embryos and early fetuses
No full textAlthough left/right differences in a configuration of the pulmonary artery (PA) and its branches are well known, there is little information as to when and how such differences are established. Examination of serial sagittal sections of 25 embryos and fetuses at 6–7 weeks of gestation demonstrated that, at O’Rahilly stages 18–20, the right earliest first branch of PA originated in the anterior side of the upper lobar bronchus and overlay the upper bronchi, in contrast to the left branch which was located posteriorly and constricted medially by the upper posterior bronchus B1 + 2b. The right earliest branch was most likely to correspond to the future superior trunk, while the left branch might be a lingual artery. At stages 21–23, the upper posterior parenchyma was still underdeveloped in the left lung, since the ductus arteriosus and the left common cardinal vein seemed to make the left upper thoracic cavity narrow. Conversely, in the right lung, the thick S2 seemed to require a double arterial supply from both the superior and inferior arterial trunks. On the left, A3 originated at the lung apex and took a long descending course along the lung anterior surface. This high position of A3 might soon be corrected by an increased volume of S3. Overall, in contrast to the lower and middle lobes, early‐developed branches of the PA did not accompany upper segmental and subsegmental bronchi. A mechanism “differential growth” seemed to explain how to correct the fetal morphology to provide the adult morphology with variations
Tensor fasciae latae muscle in human embryos and fetuses with special reference to its contribution to the development of the iliotibial tract
No full textBackground: The human tensor fasciae latae muscle (TFL) is inserted into the iliotibial tract and plays a critical role in lateral stabilisation of the hip joint. We previously described a candidate of the initial iliotibial tract that originated from the gluteus maximus muscle and extended distally.
Materials and methods: This study extended our observations by examining 30 human embryos and foetuses of gestational age (GA) 7-14 weeks (crown-to-rump length 24-108 mm). At GA 7 weeks, the TFL appeared as a small muscle mass floating in the subcutaneous tissue near the origins of the gluteus medius and rectus femoris muscles.
Results: Subsequently, the TFL obtained an iliac origin adjacent to the rectus femoris tendon, but the distal end remained a tiny fibrous mass on the vastus lateralis muscle. Until GA 10 weeks, the TFL muscle fibres were inserted into a vastus lateralis fascia that joined the quadriceps tendon distally. The next stage consisted of the TFL muscle belly "connecting" the vastus fascia and the gluteus fascia, including our previous candidate of the initial iliotibial tract. Until GA 14 weeks, the TFL was sandwiched by two laminae of the connecting fascia.
Conclusions: These findings suggested that, when the vastus lateralis fascia separated from the quadriceps tendon to attach to the tibia, possibly after birth, the resulting iliotibial tract would consist of a continuous longitudinal band from the gluteus maximus fascia, via the vastus fascia, to the tibia. Although it is a small muscle, the foetal TFL plays a critical role in the development of the iliotibial tract.Ministerio de Educación, Cultura, Deportes, Ciencia y Tecnología (Japón)Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu
Vena capitis prima and the cavernous sinus in human embryos and fetuses
No full textAfter the intracranial venous-drainage route is switched from the vena capitis prima (VCP) to the transverse sinus, the cavernous sinus is considered to develop from a connecting part of the VCP with the ophthalmic vein (OPV). Observations of histological sections from 12 embryos and 47 fetuses (6-35 weeks) demonstrated that (1) at six weeks, a major tributary of the VCP ran inferiorly in the plica ventralis at the mesencephalic flexure (future tentrium cerebelli) and merged with the OPV in the medial side of the trigeminal ganglion; (2) at seven weeks, being independent of the laterally located primary veins, the superior petrosal sinus (SPS) developed medially in the plica, ran superiorly, and appeared to make an initial confluence with the transverse sinus; (3) until 15-16 weeks, parasellar veins were limited to a few branches of the OPV without communication with the SPS on the lateral surface of the trigeminal ganglion; (4) after 15-16 weeks, parasellar veins increased in number and volume but did not yet drain into the SPS but rather into the newly built inferior petrosal sinus; and (5) near term, parasellar veins started venous drainage to the SPS, whereas few veins were evident around the intracavernous abducens nerve. Consequently, the inferior petrosal sinus might originate from a remnant of the VCP (the so-called pro-otic sinus), but after midterm, most parasellar veins appeared to develop from the OPV without any contribution of the SPS. These findings suggest that parasellar sinus-network might be established after birth.Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu
Examination of the Annular Tendon (Annulus of Zinn) as a Common Origin of the Extraocular Rectus Muscles: 2. Embryological Basis of Extraocular Muscles Anomalies
No full textPurpose: Many reports have described anomalous connections of the superior rectus (SR) with other extraocular rectus muscles, in which additional heads of the other three rectus muscles likely provided the connections. We examined how these connections are established during fetal development.
Methods: We analyzed paraffin-embedded horizontal sections from 25 late-stage fetuses. Horizontal sections are best suited for understanding the mediolateral relationships of muscle origins.
Results: We confirmed a common tendinous origin of the lateral rectus (LR), inferior rectus (IR) and medial rectus (MR) muscles that was separated from the SR origin. Notably, eight fetuses (32%) had tendinous or muscular connections between the SR and other rectus muscles that had one of four morphologies: (a) a thin tendon from the SR to the common tendon of the three rectus muscles (2 fetuses), (b) a thin tendon to the LR (one fetus), (c) a thin tendon to the inferior rectus muscle origin (two fetuses), and (d) SR muscle fibers arising from an additional head of the LR (three fetuses).
Conclusions: The SR seemed to issue a thin tendon that passed along the inferior or lateral side of the oculomotor nerve. Conversely, the LR and inferior rectus muscle were likely to carry a supernumerary bundle that reached the SR. The accessory head of the medial rectus muscle showed a stable morphology in that it seemed to also provide an anomalous double head. However, the presence of an accessory head in the LR was rare. In contrast with our previously published diagram of the orbital apex, the accessory head of the medial rectus muscle passed along the lateral side of the superior oblique.Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu
Transient connection or origin of the inferior pharyngeal constrictor during fetal development: A study using human fetal sagittal sections
No full textThe inferior pharyngeal constrictor (IPC) originates from the thyroid and cricoid cartilages and inserts to the pharyngeal raphe. In serial sagittal sections of 37 embryos and fetuses at 6–15 weeks (crown rump length 15–115 mm), we found (1) the IPC connecting to the sternothyroideus and thyrohyoideus muscles (16 fetuses at 6–11 weeks) or (2) the cricothyroideus muscle (6 fetuses at 12–15 weeks) in addition to the usual cricoid origin. These aberrant connections were most likely to be transient origins of the IPC not from a hard tissue but nearby striated muscles. In four of the latter six specimens, a tendinous band from the IPC inferior end connected to the cricothyroideus muscle to provide a digastric muscle-like appearance. These aberrant connections with nearby muscles seemed to become separated by a growing protrusion of the thyroid cartilage. Therefore, these aberrant origins were, even if developed, most likely to be “corrected” to the adult morphology during midterm or late prenatal period. The aberrant or transient origin of the IPC seemed to result from a discrepancy in growth of the cartilage and muscles. Such a discrepancy in growth seems to resemble the IPC wrapping around the superior cornu of thyroid cartilage. In addition, a final or adult-like morphology was found in two of the present 37 fetal specimens. It seemed to suggest a significant redundancy in growth rate of the laryngeal structures.JSPS KAKENHIDepto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu
Three‐dimensional analysis of the segmental arrangement of lower lung lobes in human fetuses: is this arrangement a miniature version of adult morphology?
No full textKnowledge of the lung segment system is essential for understanding human anatomy and has great clinical relevance. The arrangement of 11 segments, including the S* or subsuperior segment, and its individual variations, are considered to be the same in fetal and adult lungs. The present study assessed the topographical anatomy of lower segmental and subsegmental bronchi by computer‐assisted three‐dimensional imaging of serial sagittal sections of both lungs of 22 embryos and fetuses of gestational age 6–7 weeks (crown–rump length 15.0–28.5 mm). Long inferior courses of B8b (basal) and B10c (medial) were observed in sagittal sections of both lungs. B8a (lateral) and B10b (lateral) in the right lungs were consistently underdeveloped, with S9 occupying most of the lateral half of the lower lobe. In some samples, B6b (lateral) did not reach the lateral surface. The lateral dominance of S9 was also seen in the left lungs. Some B* candidates were present, but B7 candidates were absent. Lateral and posterior expansions of S6b, S8a and S10b to cover S9 were observed in additional midterm and near‐term lung sections, indicating that the original S9 dominance was 'corrected' by an increase in lung volume. Delayed growth of the lower lateral subsegments might induce mechanical stress, resulting in aberrant notches or fissures, such as those separating an independent posterior lobe. The segmental arrangement of fetal lungs was not stable, but was altered over a long fetal period after the complete subsegmental division of the bronchi, except for the minor bronchi B* and B7
Perineal raphe with special reference to its extension to the anus: a histological study using human fetuses
No full textThe raphe of the human penis and scrotum is considered to develop secondarily after disappearance of the initial midline seam by fusion of the bilateral genital folds. However, the fetal development was still obscure. We examined histological sections of 30 fetuses (17 males and 13 females) at 10–15 weeks. In male fetuses, the scrotum was not yet clearly identified because of no descent of testis. The perineal raphe was thin and wavy at 10 weeks, and it was continuous with and took a direction same as the inferior wall of the closed penile urethra after physiological hypospadias. Depending on growth of the bulbospongiosus muscle and corpus spongiosus penis, the midline intermuscular septum obtained a connection to the subcutaneous wavy raphe and made the latter thick and straight at 12–15 weeks. Notably, the perineal raphe extended posteriorly to attach to the external anal sphincter. In female fetuses, an epithelial fusion occurred along a short distance at the posterior end of the vestibule. However, in front of the external anal sphincter, a large midline mesenchymal tissue from the urorectal septum did not contain a raphe-like structure. Moreover, since the bilateral bulbospongiosus muscles were separated widely by the vestibule, they did not provide a midline septum. Fetal development of the perineal raphe was accelerated by reinforcement from the muscular septum. In contrast, without such a muscular support, the female raphe could not maintain its growth even if the seed appeared at the posterior end of the vestibule.National Natural Science Foundation (China)Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu
Development of the pulmonary pleura with special reference to the lung surface morphology: a study using human fetuses
No full textIn and after the third trimester, the lung surface is likely to become smooth to facilitate respiratory movements. However, there are no detailed descriptions as to when and how the lung surface becomes regular. According to our observations of 33 fetuses at 9-16 weeks of gestation (crown-rump length [CRL], 39-125 mm), the lung surface, especially its lateral (costal) surface, was comparatively rough due to rapid branching and outward growing of bronchioli at the pseudoglandular phase of lung development. The pulmonary pleura was thin and, beneath the surface mesothelium, no or little mesenchymal tissue was detectable. Veins and lymphatic vessels reached the lung surface until 9 weeks and 16 weeks, respectively. In contrast, in 8 fetuses at 26-34 weeks of gestation (CRL, 210-290 mm), the lung surface was almost smooth because, instead of bronchioli, the developing alveoli faced the external surfaces of the lung. Moreover, the submesothelial tissue became thick due to large numbers of dilated veins connected to deep intersegmental veins. CD34-positive, multilayered fibrous tissue was also evident beneath the mesothelium in these stages. The submesothelial tissue was much thicker at the basal and mediastinal surfaces compared to apical and costal surfaces. Overall, rather than by a mechanical stress from the thoracic wall and diaphragm, a smooth lung surface seemed to be established largely by the thick submesothelial tissue including veins and lymphatic vessels until 26 weeks.Ministerio de Educación, Cultura, Deportes, Ciencia y Tecnología (Japón)Depto. de Anatomía y EmbriologíaFac. de MedicinaTRUEpu
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