STUDIES ON THE ANATOMY OF LYMNAEA HUMILIS SAY

1957 ◽  
Vol 35 (6) ◽  
pp. 751-768 ◽  
Author(s):  
Bruce M. McCraw
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Male Copulatory Organ ◽  
Vas Deferens ◽  
Lymnaea Stagnalis ◽  
Copulatory Organ ◽  
Accessory Structure ◽  
Internal Organs ◽  
Distinct Entity ◽  
The Central Nervous System

The topographic anatomy of Lymnaea humilis is described, giving the relative positions of the various internal organs. A description of the anatomy of the cephalic hemocoele is also given. Like Lymnaea stagnalis the central nervous system of L. humilis consists of the paired cerebral, buccal, pedal, pleural, and parietal ganglia and the unpaired abdominal ganglion. The nerves arising from the central nervous system are described and particular attention was devoted to the nerves arising from the pedal ganglia and innervating the foot; fourteen new nerves are named or described. The reproductive system of L. humilis is divided into: (a) the ovotestis and its duct, (b) the female system, and (c) the male system. In reproductively active snails, the female system is the largest of the three portions, and consists of the uterus, oothecal gland, vagina, and seminal receptacle. An accessory structure, the albumen gland, is very large in L. humilis. The male system consists of the upper and lower prostate, vas deferens, and male copulatory organ. The connections between the hermaphrodite duct and the male and female systems show considerable structural consolidation compared to these connections in L. stagnalis. The muciparous gland is not a distinct entity in L. humilis.

Solitary Fibrous Tumors in the Central Nervous System

2003 ◽  
Vol 127 (4) ◽  
pp. 432-439 ◽  
Author(s):  
Tarik Tihan ◽  
Michael Viglione ◽  
Marc K. Rosenblum ◽  
Alessandro Olivi ◽  
Peter C. Burger
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Biological Behavior ◽  
Clinicopathologic Features ◽  
Distinct Entity ◽  
Total Resection ◽  
Solitary Fibrous Tumors ◽  
The Central Nervous System ◽  
Extracranial Metastases

Abstract Context.—Solitary fibrous tumors (SFTs) of the central nervous system are rare neoplasms that usually present as dura-based masses and clinically resemble meningiomas. Histologically, they can be similar to fibrous meningioma or hemangiopericytoma (HPC). In particular, densely cellular regions seen in some SFTs can be indistinguishable from HPC. Little is known about the biological behavior of SFTs, although most seem amenable to total resection. Objectives.—To define the clinicopathologic spectrum of SFTs in the central nervous system and to outline their differences from HPC and meningioma. Design.—We present the clinicopathologic features of 18 patients with SFT and compare them with those of an age- and sex-matched cohort of HPCs. Results.—Eleven SFTs were supratentorial, 3 were infratentorial, and 4 were intraspinal. Four of the 18 tumors were intra-axial (2 in the lateral ventricles and 2 within the spinal cord). Histologically, SFTs were similar to their soft tissue counterparts. Six tumors (6/18) had densely cellular regions, and 1 tumor showed frankly anaplastic features. All but 3 patients underwent gross total resection, and there were no metastases or tumor-related mortalities during the median follow-up of 40 months. In contrast, there were 15 local recurrences (83%), 5 extracranial metastases (27%), and 4 tumor-related deaths (22%) in the HPC cohort. Conclusions.—Our study presents the clinicopathologic features of SFT as a distinct entity from both meningioma and HPC. We also present unusual examples of anaplastic, intraventricular, and intramedullary spinal SFTs that expand the clinicopathologic spectrum of these uncommon and sometimes diagnostically difficult neoplasms.

scholarly journals Primary structure and origin of schistosomin, an anti-gonadotropic neuropeptide of the pond snail Lymnaea stagnalis

1991 ◽  
Vol 279 (3) ◽  
pp. 837-842 ◽  
Author(s):  
P L Hordijk ◽  
H D F H Schallig ◽  
R H M Ebberink ◽  
M de Jong-Brink ◽  
J Joosse
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Primary Structure ◽  
Lymnaea Stagnalis ◽  
Sequence Similarity ◽  
Infected Snail ◽  
Chain Molecule ◽  
Pond Snail ◽  
Single Chain ◽  
The Central Nervous System

In the pond snail Lymnaea stagnalis infected with the schistosome parasite Trichobilharzia ocellata, a peptide called schistosomin is released from the central nervous system, which counteracts the bioactivity of a number of gonadotropic hormones. This leads to inhibition of the reproductive activities of the infected snail. In order to determine the structure of schistosomin, the neuropeptide was purified from the central nervous system using gel-permeation chromatography and reverse-phase h.p.l.c. The complete primary structure of the peptide was determined by N-terminal sequencing and peptide mapping. Schistosomin is a single-chain molecule of 79 amino acids with a molecular mass of 8738 Da. The peptide contains eight cysteine residues which may give rise to four intramolecular disulphide bridges that fold the peptide into a stable globular structure. A database search did not reveal any known peptides that show significant sequence similarity to schistosomin. By means of immunocytochemistry, the peptide was shown to be localized in the growth-controlling neurosecretory light green cells, which are located in the cerebral ganglia of the central nervous system of Lymnaea. In addition to schistosomin, these neurons are known to produce various insulin-related peptides.

Localization of dopamine and its relation to the growth hormone producing cells in the central nervous system of the snail Lymnaea stagnalis

1991 ◽  
Vol 85 (1) ◽  
pp. 1-9 ◽  
Author(s):  
T. R. Werkman ◽  
J. van Minnen ◽  
P. Voorn ◽  
H. W. M. Steinbusch ◽  
B. H. C. Westerink ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Growth Hormone ◽  
Nervous System ◽  
Lymnaea Stagnalis ◽  
The Central Nervous System
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