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Koichiro Komatsu, Akemi Shimada, Tatsuya Shibata, Satoshi Wada, Hisashi Ideno, Kazuhisa Nakashima, Norio Amizuka, Masaki Noda and Akira Nifuji

(tissue volume (TV) (mm 2 ); Fig. 1 A, upper panel) was measured by manually tracing the boundaries between tooth root surfaces or bone surfaces and soft tissues on histological sections using Image J (NIMH, Bestheda, MD, USA). The area of bone (bone

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Kenneth A Philbrick, Stephen A Martin, Amy R Colagiovanni, Adam J Branscum, Russell T Turner and Urszula T Iwaniec

/ob mice . Peptides 28 1012 – 1019 . ( https://doi.org/10.1016/j.peptides.2007.02.001 ) 10.1016/j.peptides.2007.02.001 17346852 Iwaniec UT Wronski TJ Turner RT 2008 Histological analysis of bone . Methods in Molecular Biology 447

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A. WRIGHT, I. CHESTER JONES and J. G. PHILLIPS

SUMMARY

The histology of freshly fixed adrenal glands of Ornithorhynchus and of Tachyglossus has been investigated.

In the adrenals of both species the bulk of the chromaffin tissue was found to occur at one pole, the lower or caudal part of the gland. The adrenal cortex of Ornithorhynchus has a complicated histological appearance and comprises three main types of tissues, designated groups I-III. The major portion of the cortex was made up of groups II and III tissues which were in contiguous patches associated with blood vessels. Group I tissue was confined, for the most part, to a layer of cells lying against the chromaffin tissue. Group III tissue consisted of big cells with large nuclei which frequently contained prominent globules or vacuoles. It is possible that group III represents the secreting part of the cortex and group II the formative layer.

In Tachyglossus, the cortex had a more homogeneous appearance and was more akin to that of reptiles. There was, however, some gradation of cell types. The peripheral cells had plentiful cytoplasm with faintly basophilic nuclei, while centripetally the cells were closely packed and the nuclei densely stained.

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D. M. de KRETSER, H. P. TAFT, J. B. BROWN, J. H. EVANS and B. HUDSON

SUMMARY

The results of treatment of three oligospermic men for periods of up to 12 months with human pituitary gonadotrophin alone and in combination with human chorionic gonadotrophin (Pregnyl) is described. The addition of exogenous gonadotrophin resulted in a small but significant stimulation of spermatogenesis which was confirmed by quantitative histological assessment of testicular biopsy specimens taken before, during and after treatment. The time taken for a response in the ejaculate appears to be dependent on the initial histological appearance of the testis, in particular the stage of germinal cell arrest.

Estimations of plasma testosterone and urinary oestrogen indicate that testicular steroid biosynthesis is stimulated during treatment with gonadotrophin.

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I. DONIACH and E. P. SHARPEY-SCHAFER

Descriptions of the effect of thiouracil or thiourea upon the histology of the human thyroid have until now been limited to cases of Graves's disease [Moore, Sweeney, Cope, Rawson & Means, 1944; Shirer & Cohen, 1945; Halpert, Cavanaugh & Keltz, 1946]. In the course of a study of thiouracil therapy in heart failure the opportunity was taken to study in humans the histological stimulation first observed by MacKenzie & MacKenzie [1943] and Astwood, Sullivan, Bissell & Tyslowitz [1943] in the experimental animal, to find the degree of thyroid hyperplasia and colloid depletion evoked by increasing dosage with thiouracil, and to see at what stage of treatment changes are recognizable and how effectively the thyroid reverts to normal when the drug is stopped. This paper describes the changes in normal human thyroids and in one case the effect of additional thyrotrophic extract was studied. By 'normal', no more is implied than

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T. A. I. GRILLO, P. O. OGUNNAIKE and S. FAOYE

SUMMARY

The effects of chemical fixatives such as the aldehydes, as well as ethanol, on the insulin content of the rat pancreas were studied. Although there was some loss of insulin after the use of all the fixatives investigated it was found that glutaraldehyde preserved the greatest amount of the hormone at both room and low temperature. Insulin was still preserved in the pancreas after glutaraldehyde fixation even after the complete preparation of the tissue for histology or electron microscopy. The insulin extracted from the pancreas after fixation in formaldehyde was still biologically active and it enhanced the formation of glycogen in the rat diaphragm.

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B. A. CROSS, R. F. W. GOODWIN and I. A. SILVER

SUMMARY

1. A method has been devised for obtaining repeated biopsy samples from the mammaryglands of sows, and by its use the histological changes associated with farrowing have been studied.

2. Before farrowing, the alveoli were at first small and filled with a hyaline eosinophilic secretion. Progressive distension of the alveoli followed, accompanied by a gradual replacement of the eosinophilic material by basophilic secretion and the onset of fat secretion. At farrowing the alveoli were contracted and their contents evacuated.

3. Acute involutional changes seen in the engorged glands of early-weaned animals, or animals that were suckled with one teat occluded, were characterized by solidification of the alveoli, swollen degenerating epithelial cells and, later, stromal proliferation. Little alveolar structure remained after 8 days.

4. Descriptions are given of three main types of mammary defect that were detected histologically in clinical cases of agalactia.

5. In experiments on milk ejection, recorded manometrically, the dose-response relation to injected oxytocin was determined. Two out of three sows responded to 10 mu. and maximal responses were obtained with doses of 200–500 mu.

6. The occurrence of myoepithelial cells in the sow's mammary gland has been demonstrated by the alkaline phosphatase technique.

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G. S. GREENWALD

SUMMARY

The histology of the reproductive tract of the lactating mouse is described.

During the first 11 days post partum, the largest vesicular follicles are 350μ in diameter, the corpora lutea of pregnancy are larger than the corpora lutea of lactation, and the vagina has a two-layered epithelium. Significant changes occur after 12 days post partum: the size of the follicles in most animals increases to 400–450μ, the corpora lutea of lactation are larger than the old set, and the vagina becomes mucified.

This suggests that lactation in the mouse is divided into two periods: the first in which progesterone and negligible amounts of oestrogen are present lasts until the 11th day. This is followed by a period of increasing levels of oestrogen and a gradual subsidence in that of progesterone.

A hypothesis is proposed to account for the morphological changes that occur during lactation.

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A. H. BAILLIE

SUMMARY

Fourteen albino male mice were subjected to bilateral section and ligation of the epididymis at a point just distal to the proximal lobules of the head, and were killed 2, 4, 8, 12, 16, 20 and 24 weeks after operation. One testis was studied using the periodic acid-Schiff (PAS) technique, the other by frozen sections. The weight of the seminal vesicle was taken as an indicator of androgen output.

Testicular histology remained unchanged during the 6 months after operation, and there was no alteration in the weight or cytology of the seminal vesicles. An attempt is made to relate the findings to current views on Leydig cell biology.

The postoperative occurrence of abnormal Leydig cells is described: these cells contain abundant PAS-positive cytoplasmic material (? glycoprotein) and have not previously been noted. Their anatomical and physiological significance is not clear.

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J. LOGOTHETOPOULOS and R. F. SCOTT

SUMMARY

A histological and functional study was made of the thyroids of foetal guinea-pigs rendered goitrous by the administration of propylthiouracil (PT) to the mothers.

1. The thyroids of 30-day-old foetal guinea-pigs from PT-treated mothers were of the same weight and histological appearance as the glands of control foetuses.

2. Increased thyroid weight, loss of colloid and increased cell height were well marked in 36-day-old foetuses from treated animals.

3. The growth rate of foetal goitres was many times greater than that of corresponding maternal goitres as judged by thyroid weights and number of mitoses in 43- and 60-day-old foetuses. Expansion and folding of the follicular walls rather than increased follicle formation characterized the foetal goitres.

4. The ratios of thyroid/plasma inorganic 131I (T/Pl ratios) in 36-day-old normal and goitrous foetuses were of the same order of magnitude as found in adult animals. No significant difference was found between the T/Pl ratios of normal and goitrous foetuses and normal and goitrous pregnant animals.

5. Positive autoradiographs were obtained in 28-day-old normal foetuses and onwards. Individual thyroid uptakes (of 131I) of normal 60-day-old foetuses exceeded maternal uptakes. Goitrous foetuses showed a 'rebound' high uptake 3 days after the withdrawal of PT from the mother.

6. Untreated guinea-pigs born to mothers treated with PT were found to have true colloid goitres at ages of 4 and 8 months. Thyroid weight and average follicle size were bigger, average follicle cell height smaller than in control animals of the same ages. 131I uptakes were equal.