scholarly journals Establishment of rostrocaudal polarity in tectal primordium: engrailed expression and subsequent tectal polarity

Development ◽  
1991 ◽  
Vol 113 (4) ◽  
pp. 1133-1144 ◽  
Author(s):  
N. Itasaki ◽  
H. Ichijo ◽  
C. Hama ◽  
T. Matsuno ◽  
H. Nakamura
Keyword(s):  
Staining Pattern ◽  
Mirror Image ◽  
Original Position ◽  
Positive Staining ◽  
Caudal Part ◽  
Retinotectal Projection ◽  
Projection Pattern ◽  
Rostrocaudal Axis ◽  
Positional Value ◽  
Tectal Polarity

In the E4 (embryonic day 4) chick tectal primordium, engrailed expression is strong at the caudal end and gradually weakens toward the rostral end. We used quail-chick chimeric tecta to investigate how the caudorostral gradient of engrailed expression is established and whether it is correlated with the subsequent rostrocaudal polarity of tectal development. To examine the positional value of the tectal primordium, we produced ectopic tecta in the diencephalon by transplanting a part of the mesencephalic alar plate heterotopically. In the ectopic tectum, the gradient of the engrailed expression reversed and the strength of the expression was dependent on the distance from the mes-diencephalon junction; the nearer the ectopic tectum was to the junction, the weaker the expression was. Consequently, the pattern of the engrailed expression in the host and ectopic tecta was nearly a mirror image, suggesting the existence of a repressive influence around the mes-diencephalon junction on the engrailed expression. We examined cytoarchitectonic development in the ectopic tecta, which normally proceeds in a gradient along the rostrocaudal axis; the rostral shows more advanced lamination than the caudal. In contrast, the caudal part of the ectopic tecta (near to the mes-diencephalon junction) showed more advanced lamination than the rostral. In both the host and ectopic tecta, advanced lamination was observed where the engrailed expression was repressed, and vice versa. Next we studied the correlation between engrailed expression and retinotectal projection from a view of plasticity and rigidity of rostrocaudal polarity in the tectum. We produced ectopic tecta by anisochronal transplantations between E3 host and E2 donor, and showed that there is little repressive influence at E3 around the mes-diencephalon junction. We then made chimeric double-rostral tectum (caudal half of it was replaced by rostral half of the donor tectum) or double-caudal tectum at E3. The transplants kept their original staining pattern in hosts. Consequently, the chimeric tecta showed wholly negative or positive staining of engrailed protein on the grafted side. In such tecta retinotectal projection pattern was disturbed as if the transplants retained their original position-specific characters. We propose from these heterotopic and anisochronal experiments that the engrailed expression can be a marker for subsequent rostrocaudal polarity in the tectum, both as regards cytoarchitectonic development and retinotectal projection.

scholarly journals COMPARATIVE STUDIES OF LIGHT MEROMYOSIN PARACRYSTALS DERIVED FROM RED, WHITE, AND CARDIAC MUSCLE MYOSINS

1971 ◽  
Vol 49 (3) ◽  
pp. 883-898 ◽  
Author(s):  
A. Nakamura ◽  
F. Sreter ◽  
J. Gergely
Keyword(s):  
Molecular Structure ◽  
Cardiac Muscle ◽  
Functional Properties ◽  
Comparative Studies ◽  
White Muscle ◽  
Staining Pattern ◽  
Uranyl Acetate ◽  
Positive Staining ◽  
Cardiac Muscles

Tryptic and chymotryptic light meromyosin paracrystals from red and cardiac muscles of rabbit show a negative and positive staining pattern with uranyl acetate and phosphotungstate that sharply differs from that of white muscle light meromyosin paracrystals. The main periodicity of about 430 A is the same regardless of the source of light meromyosin. The results are discussed in terms of the molecular structure and the functional properties of various myosins.

Retino-tectal projections from half-ventral and half-dorsal eye rudiments in Xenopus

Development ◽  
1978 ◽  
Vol 46 (1) ◽  
pp. 89-97
Author(s):  
Joan D. Feldman
Keyword(s):  
Mirror Image ◽  
Retinotectal Projection ◽  
Larval Stages

When the ventral half of a developing eye in Xenopus larvae was removed at stage 32, the remaining fragment rounded up and developed into an eye which looked macroscopically normal by mid-larval stages. Eyes from half-dorsal rudiments were usually small, had more than one ventral fissure, and showed abnormal pupils. The contralateral retinotectal projection was always found to be normally ordered when mapped in later tadpole stages, or, just after metamorphosis. No mirror-image duplicated maps were seen, as was found previously in eyes deriving from half-nasal and half-temporal rudiments. It is concluded that the ‘rule of distal transformation’ does not apply to eyes which are generated from embryonic rudiments.

scholarly journals A Case of Silent Corticotroph Adenoma

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A563-A563
Author(s):  
Usonwanne U Ibekwe ◽  
Nathan Zwagerman ◽  
Srividya Kidambi ◽  
Jerald Peter Marifke
Keyword(s):  
Pituitary Adenoma ◽  
Cavernous Sinus ◽  
Endoscopic Resection ◽  
Staining Pattern ◽  
Positive Staining ◽  
Sellar Mass ◽  
Post Surgery ◽  
Morning Cortisol ◽  
Patient Reported ◽  
The Right

Abstract Background: Silent Corticotroph Adenomas (SCAs) are tumors with no biochemical or clinical features consistent with hypercortisolism but have positive immunostaining for ACTH. They account for approximately 1.1-6% of all pituitary adenomas and 5.5% of nonfunctioning adenomas. Clinical Case: A 49-year-old woman presented to clinic with a 6-month history of headache, vision changes, fatigue, hair thinning, brittle nails, lightheadedness, polydipsia, easy bruising, increased appetite, and weight gain of 178 pounds in 2 years. Labs obtained: morning cortisol 10 mcg/dl(7-25 mcg/dl), ACTH 59 pg/ml(7.2-63 pg/ml), IGF-1 96 ng/ml(52-328 ng/ml), LH 0.2 mIU/ml(1.9-12.5 mIU/ml), FSH 0.8 mIU/ml(2.5-10.2mIU/ml), alpha subunit <0.1 ng/ml(52-328 ng/ml), TSH 0.991 uIU/ml(0.358-3.74 uIU/ml), free T4 1.12 ng/dl(0.76-1.46 ng/dl), salivary cortisol 66 ng/dl(<100 ng/dl), 24-hour urine cortisol 10 mcg/24hr(3.5-45 mcg/24hr) and prolactin 64.3 ng/ml(2.8-29.2 ng/ml). No hook effect noted with serial dilution. MRI brain showed a 22 x 29 x 26 mm sellar mass extending into the suprasellar cistern displacing and compressing the optic nerves and chiasm superiorly with partial invasion into the right cavernous sinus. She had an endoscopic resection of the sellar mass. She developed diabetes insipidus post-operatively and required desmopressin transiently. In the immediate post-operative period, morning cortisol and ACTH were 16.9 ug/dl(6.2-19.4 ug/dL) 24.8 pg/ml(7.2-63.3 pg/ml) respectively. She was sent home without steroids. Pathology showed a staining pattern consistent with pituitary adenoma with positive staining for ACTH. One month after her surgery she was admitted with symptoms of orthostatic hypotension. Cortisol at 5pm was 3 ug/dl(2.3-11.9 ug/dl), ACTH 31.7 pg/ml(7.2-63.3pg/ml). She had a cosyntropin stimulation test done with peak cortisol of 19.3 ug/dl at 60 minutes. Due to her symptoms, she was started on oral hydrocortisone (HC) for secondary adrenal insufficiency (AI), but was eventually tapered off the steroids. Six months after her surgery, she developed worsening headaches. Repeat MRI obtained showed significant growth of the residual adenoma on the right side of the sella, invading the cavernous sinus. Morning cortisol level of 5.3 mcg/dl(4.3-22.4 mcg/dl) and ACTH level was 11 pg/ml(6-50 pg/ml). She had a repeat endoscopic resection of the pituitary tumor. Her post-surgery cortisol at 2 PM was 3 mcg/dl at which time patient reported symptoms of AI. She was discharged on HC. Pathology again showed a staining pattern consistent with pituitary adenoma with positive staining for ACTH. MIB-1 proliferative index was 5.6%. P53 immunostaining showed a moderate density of moderately intense nuclei in the adenoma. Conclusion: This case illustrates aggressive nature of SCAs with higher risk of recurrence compared to other non-functioning adenomas and therefore requires close follow up.

scholarly journals Occurrence and Antigenic Specificity of Perinuclear Anti-Neutrophil Cytoplasmic Antibodies (P-ANCA) in Systemic Autoimmune Diseases

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 2128
Author(s):  
Ourania D. Argyropoulou ◽  
Andreas V. Goules ◽  
Georgios Boutzios ◽  
Alexandra Tsirogianni ◽  
Charalampos Sfontouris ◽  
...  
Keyword(s):  
Autoimmune Diseases ◽  
Lupus Erythematosus ◽  
Staining Pattern ◽  
The Other ◽  
Cathepsin G ◽  
Antigenic Specificity ◽  
Positive Staining ◽  
Systemic Lupus ◽  
Systemic Autoimmune Diseases ◽  
Autoimmune Rheumatic Diseases

Perinuclear anti-neutrophilic cytoplasmic antibodies (P-ANCA) recognize heterogeneous antigens, including myeloperoxidase (MPO), lactoferrin, elastase, cathepsin-G and bactericidal/permeability-increasing protein. Although P-ANCA have diagnostic utility in vasculitides, they may also be found in patients with various other systemic autoimmune rheumatic diseases (SARDs). Nevertheless, the clinical significance and the targets recognized by P-ANCA in such patients remain unclear. For this purpose, herein we investigated the occurrence of ANCA-related antigenic specificities in 82 P-ANCA-positive sera by multiplex ELISA, as well as their association with other autoantibodies. The P-ANCA-positive sera corresponded to patients with vasculitides (n = 24), systemic lupus erythematosus (n = 28), antiphospholipid syndrome (n = 5), Sjögren’s syndrome (n = 7), rheumatoid arthritis (n = 3), systemic scleroderma (n = 1), sarcoidosis (n = 1) and Hashimoto′s thyroiditis (n = 13). In most P-ANCA-positive patients studied (51/82, 62.3%), these autoantibodies occurred in high titers (>1:160). The analysis of P-ANCA-positive sera revealed reactivity to MPO in only 50% of patients with vasculitides, whereas it was infrequent in the other disease groups studied. Reactivity to other P-ANCA-related autoantigens was also rarely detected. Our findings support that high P-ANCA titers occur in SARD. The P-ANCA-positive staining pattern is associated with MPO specificity in vasculitides, while in other autoimmune diseases, it mostly involves unknown autoantigens.

A study of the retinotectal projection during regeneration of the optic nerve in the frog

1963 ◽  
Vol 157 (968) ◽  
pp. 420-448 ◽  
Keyword(s):  
Optic Nerve ◽  
Rana Temporaria ◽  
Complete Recovery ◽  
Mirror Image ◽  
Nerve Section ◽  
Retinotectal Projection ◽  
Negative Results ◽  
Partial Organization ◽  
Ipsilateral Projection ◽  
Normal Projection

The retinotectal projection was mapped electrophysiologically in 67 experiments on Rana temporaria at various intervals (from 23 to 247 days) after section of the optic nerve. In 18 animals regeneration had not occurred at the time of recording; in the others the pro­jections could be classified in the following way, according to the degree of normality of the pattern: Pattern 1: In 14 frogs there was disorganized anomalous regeneration from small regions of the retina. Tectal responses could not be evoked from the normal stimulus positions but could be evoked only from one or two localized regions of visual field. In 8 of these frogs there was one circumscribed region in the nasal half of the field and another in the temporal half from which responses could be obtained; in 4 animals there was only one region, in the nasal field, and in 2 animals there was one region, in the temporal field, from which tectal responses could be evoked. The earliest responses recorded after nerve section were of pattern 1. Pattern 2: In 4 frogs there was an abnormal projection showing partial organization in only one axis of the retina (nasotemporal, circumferential) and in only one axis of the tectum (mediolateral). This partial organization was only found at the rostral end of the tectum. Pattern 3: In 12 frogs there was recovery of the normal retinotectal projection. Pattern 4: In 15 frogs there was partial or complete recovery of the normal projection together with an anomalous but retinotopically organized projection to the wrong half to the brain. This latter projection was organized as a mirror image of the normal ipsilateral projection. One frog combined the elements of patterns 1 and 4 and the remaining 3 animals did not conform to any of the above patterns. Most of the negative results were obtained in the early days after nerve section and all recordings made later than 77 days after section gave responses. Patterns 3 and 4 were obtained more frequently the longer the interval between nerve section and recording.

Rotation of the tectal primordium reveals plasticity of target recognition in retinotectal projection

Development ◽  
1990 ◽  
Vol 110 (2) ◽  
pp. 331-342 ◽  
Author(s):  
H. Ichijo ◽  
S. Fujita ◽  
T. Matsuno ◽  
H. Nakamura
Keyword(s):  
Ganglion Cells ◽  
Early Stage ◽  
Target Recognition ◽  
Experimental System ◽  
Caudal Part ◽  
Retinotectal Projection ◽  
Somite Stage ◽  
Retinal Axons ◽  
Stage Of Development ◽  
Rostral Part

Retinotectal projection is precisely organized in a retinotopic manner. In normal projection, temporal retinal axons project to the rostral part of the tectum, and nasal axons to the caudal part of the tectum. The two-dimensional relationship between the retina and the tectum offers a useful experimental system for analysis of neuronal target recognition. We carried out rotation of the tectal primordium in birds at an early stage of development, around the 10-somite stage, to achieve a better understanding of the characteristics of target recognition, especially the rostrocaudal specificity of the tectum. Our results showed that temporal retinal axons projected to the rostral part of the rotated tectum, which was originally caudal, and that nasal axons projected to the caudal part of the rotated tectum, which was originally rostral. Therefore, the tectum that had been rotated at the 10-somite stage received normal topographic projection from the retinal ganglion cells. Rostrocaudal specificity of the tectum for target recognition is not determined by the 10-somite stage and is acquired through interactions between the tectal primordium and its surrounding structures.

Life After Death

2020 ◽  
Author(s):  
Kavita Gaur ◽  
Puja Sakhuja ◽  
Kaushik Majumdar ◽  
Divya Arora Thakral
Keyword(s):  
Staining Pattern ◽  
Performance Characteristics ◽  
Positive Staining ◽  
Quality Maintenance ◽  
Life After Death ◽  
Staining Result ◽  
Background Staining

Abstract Objectives To test the performance characteristics of 69 primary immunohistochemistry antibodies after expiration and compare with fresh primary antibodies wherever possible. Methods A total of 69 expired primary antibodies were evaluated for specificity, background staining, and intensity. An optimal staining result corresponded to a semiquantitatively scored 2+ or 3+ intensity, with intact specificity devoid of moderate or strong background staining. Any deviation from a normal staining pattern was also considered to be a suboptimal result. Results Nearly half of the antibodies studied showed an optimally positive staining result after expiration (34/69, 49.2%). Overall, 10.1% (7/69) of antibodies could be compared with fresh primary antibodies of the same clone with equivalent results. Eight of 69 (11.6%) expired antibodies showed splotchy or granular staining. Conclusions Evidence from this study and previous work point to maintained functionality of a fair number of primary immunohistochemical antibodies after expiration. Decisions about the use of such reagents should be guided by a thorough assessment of functionality by the pathologist rather than a manufacturer-specified deadline. Quality maintenance should imply a sensible balance between histopathologic performance and economics.

scholarly journals Anti-Ovarian Vessels Antibodies in P. aeruginosa Rabbit Hyper Immune Sera, an Immunohistochemical Study

2017 ◽  
Vol 28 (1) ◽  
pp. 60
Author(s):  
Noor Al-Huda A. Saeed
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Endothelial Cell ◽  
Corpus Luteum ◽  
Blood Vessels ◽  
Immunohistochemical Study ◽  
Staining Pattern ◽  
The Other ◽  
Positive Staining ◽  
Rabbit Immunoglobulin ◽  
Tunica Adventitia

Cyclical angiogenesis in the ovary is a unique process supporting normal folliculogenesis as well as lute genesis. In this report we investigated the reactivity of rabbit anti pseudomonas aeruginosa antisera with ovarian blood vessels. Tissues stained with anti-sera were immunohistochemically visualized using biotinylated anti rabbit immunoglobulin and peroxidase conjugated streptavidin. Positive staining sites depend on anti-stain type, however, staining was observed in endothelial cell and tunica adventitia in most cases.On the other hand, corpus luteum blood vessels showed a positive staining pattern as well. We conclude from this study that a peculiar staining pattern was seen in ovarian blood vessels stained with rabbit anti-pseudomonas aeruginosa hyper immune sera, the importance of this reactivity need further investigation.

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