A Comparative Study of the Spermatophores of three Scyllarid Lobsters (Parribacus Antarcticus, Scyllarides Squammosus, and Scyllarus Martensii)

1954 ◽  
Vol s3-95 (30) ◽  
pp. 205-215
Author(s):  
DONALD C. MATTHEWS
Keyword(s):  
Epithelial Cells ◽  
Comparative Study ◽  
Systematic Position ◽  
Mitotic Division ◽  
Germinal Epithelium ◽  
Collecting Tubule ◽  
Rhythmical Activity ◽  
Homogeneous Matrix

1. In Parribacus antarcticus and Scyllarus martensii mitotic division of germinal epithelial cells produces primary spermatocytesy whereas in Scyllarides squammosus this function of the germinal epithelium is limited to comparatively few large, oocytelike cells. 2. Metamorphosing spermatids in all three species are expelled from the sacculi of the testis by the rhythmical activity of their germinal epithelium. This probably accounts also for the clumping of the spermatozoa in the collecting tubule; each clump represents the extended contents of a single sacculus. 3. In Scyllarus martensii and Scyllarides squammosus a continuous, cord-like, encapsulated spermatogenic mass traverses the vasa deferentia, whereas in Parribacus antarcticus the spermatogenic mass separates into distinct ampullae which become encapsulated and are further provided with an enveloping sheath. This sheath between adjacent ampullae becomes ribbon-like, twists, and ultimately forms short, doubly twisted peduncles. 4. A secretion of the typhlosole in all three species surrounds the completed spermatophores and forms the homogeneous matrix. 5. Although these three species are anatomically similar, the spermatophores of Scyllarus martensii and Scyllarides squammosus resemble non-pedunculate spermatophores of the palinurids, the astacids, the homarids, and the nephropsids, whereas those of Parribacus antarcticus more nearly resemble the pedunculate spermatophores of certain pagurids. 6. Spermatophoric evidence above does not justify the inference that Parribacus antarcticus occupies a systematic position intermediate between the Macrura and the Anomura.

scholarly journals The Origin of the Spermatophoric Mass of the Sand Crab, Hippa pacifica

1956 ◽  
Vol s3-97 (38) ◽  
pp. 257-268
Author(s):  
DONALD C. MATTHEWS
Keyword(s):  
Epithelial Cells ◽  
Cross Section ◽  
Vas Deferens ◽  
Systematic Position ◽  
Mitotic Division ◽  
Homogeneous Matrix ◽  
Basal Foot

1. In Hippa pacifica, mitotic division of germinal epithelial cells produces primary spermatocytes which, as sustentacular-like cells appear, divide meiotically to form spermatids. 2. Concurrently as spermatids metamorphose into spermatozoa, germinal epithelial cells renew their activity and again produce primary spermatocytes which, as they fill the sacculus, expel the spermatozoa. 3. A continuous spermatogenic mass enters the vas deferens, where an enveloping secretion from the epithelial cells bounding the lumen forms a thin sheath to the sperm mass. 4. The lumen (viewed in cross-section) becomes keyhole-shaped and a secretion from a wedge-shaped group of cells bounded by two deep crypts both surrounds the sheathed sperm mass and forms a ribbon-like supporting stalk and a broad, basal foot. 5. As the lumen again becomes circular (in cross-section), a secretion from the epithelial cells surrounds the completed spermatophore and forms the homogeneous matrix. 6. The spermatophore of H. pacifica is both macruran-like, because of its continuous, highly convoluted sperm mass, and anomuran-like, because of its raised spermatophore and broad foot. 7. Neither the anomuran-like spermatophore of a macruran, Parrabicus antarcticus, nor the macruran-like spermatophore of an anomuran, Hippa pacifica, justifies the inference that these two animals occupy a systematic position intermediate between the Macrura and the Anomura, but rather illustrates the need for consideration of many characters before postulating relationships.

Parallel effects of Pulsatilla and exogenous leutocyclin on the rat ovary, uterus and thyroid

1978 ◽  
Vol 67 (04) ◽  
pp. 265-275 ◽  
Author(s):  
Suresh Prasad ◽  
K. Chandrasekhar
Keyword(s):  
Epithelial Cells ◽  
Comparative Study ◽  
Ovarian Follicles ◽  
Mitotic Division ◽  
Albino Rats ◽  
Corpora Lutea ◽  
Luminal Epithelium ◽  
Simultaneous Decrease ◽  
Rat Ovary

SummaryA comparative study of Pulsatilla (a homœopathic medicine) and leutocyclin was undertaken in female albino rats showing regular oestrus cycles. Pulsatilla in the 30th and 200th potencies was administered orally, and leutocyclin was injected in doses of 0·125 mg and 1·25 mg. 0·25 ml/dose of 90 per cent. alcohol was used as the vehicle. Pulsatilla 30 and 200 and leutocyclin at a dose of 1·25 mg markedly reduced the weight of the ovary. The higher dose of leutocyclin (1·25 mg) and both the attenuations of Pulsatilla increased the process of atresia in ovarian follicles. But a simultaneous decrease in the number and diameters of the corpora lutea was observed.Administration of Pulsatilla and leutocyclin resulted in reduction in the weight of the uterus and the height of the endometrium and luminal epithelium. There was also a reduction in the height of epithelial cells in the thyroid. Both Pulsatilla and leutocyclin enhanced mitotic division in the uterine stroma.The results indicate that leutocyclin in doses of between 0·125 mg and 1·25 mg may be used to produce similar changes in the ovary, uterus and thyroid of the rat as Pulsatilla 30 and 200.

scholarly journals Comparative study of PM2.5 - and PM10 - induced oxidative stress in rat lung epithelial cells

2004 ◽  
Vol 5 (1) ◽  
pp. 11 ◽  
Author(s):  
Jin Hyuk Choi ◽  
Jun Sung Kim ◽  
Young Chul Kim ◽  
Yoon Shin Kim ◽  
Nam Hyun Chung ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Epithelial Cells ◽  
Comparative Study ◽  
Lung Epithelial Cells ◽  
Rat Lung ◽  
Lung Epithelial ◽  
Pm2.5 And Pm10

A Comparative Study of Metridium senile (L.) var. dianthus (Ellis) and a Dwarf Variety of this Species occurring in the River Mersey, with a discussion on the Systematic Position of the Genus Metridium

1934 ◽  
Vol 19 (2) ◽  
pp. 901-919 ◽  
Author(s):  
Ruth Rawlinson
Keyword(s):  
Comparative Study ◽  
Close Agreement ◽  
Systematic Position ◽  
Special Study ◽  
Metridium Senile ◽  
Typical Form ◽  
The Family ◽  
Single Genus ◽  
Sexually Mature ◽  
Dwarf Variety

1. A special study has been made of a small Metridiuni-like anemone found at Dingle, Liverpool, in comparison with the typical form of Metridium senile (L.) var. dianthus (Ellis).2. Penicilli, formerly believed to be absent from the acontia of typical M. senile, have been discovered in abundance in the young, but rarely in the adults. In young and sexually mature specimens of the Dingle anemone they are also abundant.3. There is close agreement between the anatomy of the Dingle form and the typical M. senile.4. A considerable amount of variation occurs in the Dingle anemone, as in M. senile var. dianthus and M. marginatum, Mime-Edwards.5. The resemblances and differences between the Dingle form and M. senile indicate that the former is a dwarf variety of the latter.6. The discovery of an abundance of penicilli in the acontia of young typical M. senile and mature specimens of the Dingle variety, in conjunction with the great amount of variation in the genus Metridium, suggests that a reconsideration of the systematic position of the genus is necessary and would justify either the restriction of the family Metridiidæ to the single genus Metridium, or else the fusion of the Metridiidæ with the Sagartiidæ. The sum of the evidence appears to lie in favour of placing the genus in a family by itself.

Mechanoregulation of intracellular Ca2+ in human autosomal recessive polycystic kidney disease cyst-lining renal epithelial cells

2008 ◽  
Vol 294 (4) ◽  
pp. F890-F899 ◽  
Author(s):  
Rajeev Rohatgi ◽  
Lorenzo Battini ◽  
Paul Kim ◽  
Sharon Israeli ◽  
Patricia D. Wilson ◽  
...  
Keyword(s):  
Kidney Disease ◽  
Epithelial Cells ◽  
Polycystic Kidney Disease ◽  
Cell Lines ◽  
Autosomal Recessive ◽  
Polycystic Kidney ◽  
Renal Epithelial Cells ◽  
Collecting Tubule ◽  
Intracellular Ca ◽  
Cyst Lining

Mutations of cilia-expressed proteins are associated with an attenuated shear-induced increase in intracellular Ca2+ concentration ([Ca2+]i) in renal epithelial cell lines derived from murine models of autosomal recessive polycystic kidney disease (ARPKD). We hypothesized that human ARPKD cyst-lining renal epithelial cells also exhibited dysregulated mechanosensation. To test this, conditionally immortalized cell lines derived from human fetal ARPKD cyst-lining (pool and clone 5E) cell lines with low levels of fibrocystin/polyductin expression and age-matched normal collecting tubule [human fetal collecting tubule (HFCT) pool and clone 2C] cell lines were grown in culture, loaded with a Ca2+ indicator dye, and subjected to laminar shear. Clonal cell lines were derived from single cells present in pools of cells from cyst-lining and collecting tubules, microdissected from human kidney. Resting and peak [Ca2+]i were similar between ARPKD 5E and pool, and HFCT 2C and pool; however, the flow-induced peak [Ca2+]i was greater in ARPKD 5E (700 ± 87 nM, n = 21) than in HFCT 2C (315 ± 58 nM, n = 12; P < 0.01) cells. ARPKD 5E cells treated with Gd3+, an inhibitor of nonselective cation channels, inhibited but did not abolish the shear-induced [Ca2+]i transient. Cilia were ∼20% shorter in ARPKD than HFCT cells, but no difference in ciliary localization or total cellular expression of polycystin-2, a mechanosenory Gd3+-sensitive cation channel, was detected between ARPKD and HFCT cells. The intracellular Ca2+ stores were similar between cells. In summary, human ARPKD cells exhibit an exaggerated Gd3+-sensitive mechano-induced Ca2+ response compared with controls; whether this represents dysregulated polycystin-2 activity in ARPKD cells remains to be explored.

scholarly journals RENEWAL OF CELLS WITHIN TASTE BUDS

1965 ◽  
Vol 27 (2) ◽  
pp. 263-272 ◽  
Author(s):  
Lloyd M. Beidler ◽  
Ronald L. Smallman
Keyword(s):  
Epithelial Cells ◽  
Life Span ◽  
Tritiated Thymidine ◽  
Mitotic Division ◽  
Considerable Change ◽  
Chemical Stimulation ◽  
Taste Bud ◽  
Average Cell ◽  
Daughter Cells ◽  
Rat Tongue

Colchicine blocks mitotic division of the epithelial cells surrounding the taste bud of the rat tongue. Response to chemical stimulation decreases 50 per cent 3 hours after colchicine injection as measured by recording the electrical activity from the taste nerve bundle. Radioautography, using tritiated thymidine, shows that those epithelial cells surrounding the taste bud divide and that some of the daughter cells enter the taste bud and slowly move toward the center. The life span of the average cell is about 250 ± 50 hours, although some cells have a much shorter and others a much longer life span. These studies suggest that the cells within the taste bud, as well as the nerves, undergo considerable change with time. Corresponding changes in function are considered.

scholarly journals A comparative study for selectivity of micronuclei in oral exfoliated epithelial cells

2012 ◽  
Vol 29 (4) ◽  
pp. 230 ◽  
Author(s):  
S Grover ◽  
ABR Mujib ◽  
A Jahagirdar ◽  
N Telagi ◽  
PG Kulkarni
Keyword(s):  
Epithelial Cells ◽  
Comparative Study

Comparative study on Rickettsia-like organisms in the midgut epithelial cells of differentGlossinaspecies

Parasitology ◽  
1991 ◽  
Vol 102 (2) ◽  
pp. 193-199 ◽  
Author(s):  
M. K. Shaw ◽  
S. K. Moloo
Keyword(s):  
Electron Microscopy ◽  
Epithelial Cells ◽  
Comparative Study ◽  
Trypanosoma Congolense ◽  
Infection Rates ◽  
Cell Cytoplasm ◽  
Glossina Morsitans ◽  
Host Cell Cytoplasm ◽  
Glossina Morsitans Centralis ◽  
Micro Organisms

SUMMARYThe midgut epithelium ofGlossina morsitans centralis, G. austeni, G. pallidipes, G. palpalis palpalis, G. p. gambiensis, G. fuscipes fuscipes, G. tachinoidesandG. brevipalpisfrom ILRAD-bred colonies was examined, by electron microscopy, for the presence and distribution of Rickettsia-like organisms (RLOs). RLOs were present in the midgut epithelial cells of all non-teneral tsetse. InG. m. centralis, G. pallidipesand, to a much lesser extent,G. brevipalpis, RLOs were numerous and were present in all the specimens examined. RLOs were present in fewer numbers in the epithelial cells of tenerals of these three tsetse species. In contrast, RLOs occurred in very much lower numbers within the midgut cells of nonteneralG. austeni, G. p. palpalis, G. p. gambiensis, G. f. fuscipesandG. tachinoides; were not seen in every specimen, and were rarely observed in the midgut cells of teneral tsetse. The RLOs were typical rod-shaped bacteria with an inner and outer membrane, which occurred free within the host cell cytoplasm and appeared to cause no obvious pathology. The micro-organisms divided by binary fission and at least two distinct morphological forms plus a range of intermediate forms were seen in the midgut cells. A comparison of the presence and numbers of RLOs within the midgut cells and the midgut infection rates of bothTrypanosoma congolenseandT. b. brucei, both betweenGlossinaspecies and also within the same stock of tsetse, clearly indicates that the ability of trypanosomes to establish and develop to mature infections is unlikely to be correlated solely with the presence of RLOs within the tsetse midgut.

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