Aberrant Vein Within Common Connective Tissue Sheath of the Sciatic Nerve at the Popliteal Fossa

1. Quiescent sciatic nerve of the frog discharges CO2 at the average rate of 0.00876 mg. CO2 per gram of nerve per minute. 2. Sciatic nerve steeped one minute in boiling water discharges CO2 at first at a low rate and after an hour and a half not at all. 3. Degenerated sciatic nerve discharges CO2 at a slightly higher rate than normal living nerve does. 4. Connective tissue from the frog discharges CO2 at an average rate of 0.0097 mg. per gram of tissue per minute. 5. Assuming that a nerve is composed of from one-half to one-quarter connective tissue the CO2 output from its strictly nervous components is estimated to be at a rate of 0.008 mg. CO2 per gram of nerve per minute. 6. Stimulated sciatic nerve increases the rate of its CO2 output over quiescent nerve by about 14 per cent. When this number is corrected for strictly nervous tissue the rate is about 16 per cent. 7. The increased rate of CO2 production noted on stimulation in normal sciatic nerves was not observed when they were boiled, blocked, or degenerated. It was also not observed with stimulated strands of connective tissue.

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The Ultrastructure of the Perineurium in two Insect Species, Carausius Morosus and Periplaneta Americana

Journal of Cell Science ◽

10.1242/jcs.2.1.119 ◽

1967 ◽

Vol 2 (1) ◽

pp. 119-128

Author(s):

S. H. P. MADDRELL ◽

J. E. TREHERNE

Keyword(s):

Connective Tissue ◽

Periplaneta Americana ◽

Fluid Transport ◽

Insect Species ◽

Carausius Morosus ◽

Insect Central Nervous System ◽

Connective Tissue Sheath ◽

Extracellular Sodium ◽

Perineurial Cells ◽

Cellular Layer

The organization of the perineurium in two insect species (Carausius morosus and Periplaneta americana) has been examined with the electron microscope. In both species this cellular layer has been found to possess an extensive system of tortuous channels between the lateral cell walls. These channels are open at the outer margin adjacent to the fibrous connective-tissue sheath, but appear to be closed at the inner margin by regions of septate desmosomes and/or ‘tight’ junctions. There is an increased surface area at the inner margin of the perineurial cells produced by the presence of long inwardly directed flanges. An electron-dense coat has also been identified on the cytoplasmic side of the type II perineurial cell membranes at points of contact with the underlying extracellular system and at the outer surface adjacent to the connective-tissue sheath. This organization of the perineurium is strikingly similar to that observed in a variety of fluid-secreting epithelia and its possible function in fluid transport is discussed in relation to the available evidence on the physiology of the insect central nervous system. It is suggested, contrary to some earlier suppositions, that the perineurium may not be primarily involved in the control of the extracellular sodium level and that this regulation may be effected at a deeper level in the central nervous tissues.

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A case of Giant Perifollicular Fibroma - a Diagnostic Challenge

Serbian Journal of Dermatology and Venerology ◽

10.2478/sjdv-2020-0004 ◽

2020 ◽

Vol 12 (1) ◽

pp. 19-21

Author(s):

Raghavendra Rao ◽

Srilatha Parampalli Srinivas ◽

Varsha M. Shetty

Keyword(s):

Connective Tissue ◽

Head And Neck ◽

Neck Region ◽

Diagnostic Challenge ◽

Head And Neck Region ◽

Internal Malignancy ◽

Essential Tool ◽

Proliferative Lesion ◽

Connective Tissue Sheath

AbstractPerifollicular fibroma (PFF) is a rare proliferative lesion originating from the perifollicular connective tissue sheath. It may be congenital or acquired manifesting as skin colored to pink, asymptomatic papules of 1-5 mm in size. They are commonly distributed in the head and neck region. Multiple PFFs may be associated with internal malignancy or as a part of Birt-Hogg-Dube syndrome. Histopathology serves as an essential tool in clinching the diagnosis. Herein we report a case of giant congenital PFF.

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Subcutaneous reaction to silicone in ventriculoperitoneal shunts

Journal of Neurosurgery ◽

10.3171/jns.1974.41.3.0367 ◽

1974 ◽

Vol 41 (3) ◽

pp. 367-371 ◽

Cited By ~ 26

Author(s):

Oscar Sugar ◽

Orville T. Bailey

Keyword(s):

Cerebrospinal Fluid ◽

Connective Tissue ◽

Fibrous Connective Tissue ◽

Subcutaneous Implantation ◽

Content Type ◽

Ventriculoperitoneal Shunts ◽

Silicone Tubing ◽

Connective Tissue Sheath ◽

Fine Print

✓Silicone tubing (Silastic) used for ventriculoperitoneal shunts induces a fibrous connective tissue sheath around the tubing in children and adults. Two children examined 8 and 3 years after subcutaneous implantation showed a complete tube of dense fibrous connective tissue around the silicone tubing. The reaction was entirely quiescent. These tubes of connective tissue were apparently capable of conveying cerebrospinal fluid for some months after the silicone tubing was disconnected from the pump or pulled out of the abdomen.

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A Common Epineural Sheath for the Nerves in the Popliteal Fossa and Its Possible Implications for Sciatic Nerve Block

Anesthesia & Analgesia ◽

10.1213/00000539-199702000-00028 ◽

1997 ◽

Vol 84 (2) ◽

pp. 387-390 ◽

Cited By ~ 98

Author(s):

Jerry D. Vloka ◽

Admir Hadzic ◽

Jonathan B. Lesser ◽

Eric Kitain ◽

Harold Geatz ◽

...

Keyword(s):

Sciatic Nerve ◽

Nerve Block ◽

Popliteal Fossa ◽

Sciatic Nerve Block

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The Connective Tissue Sheath of the Locust Nervous System: A Histochemical Study

Journal of Cell Science ◽

10.1242/jcs.s3-100.51.401 ◽

1959 ◽

Vol s3-100 (51) ◽

pp. 401-412

Author(s):

DOREEN E. ASHHURST

Keyword(s):

Nervous System ◽

Connective Tissue ◽

Collagen Type ◽

Histochemical Study ◽

Locusta Migratoria ◽

System A ◽

Large Numbers ◽

Connective Tissue Sheath ◽

Cellular Layer ◽

Sheath Cells

The connective tissue sheath surrounding the nervous system of Locusta migratoria has been studied histochemically. It consists of an outer non-cellular layer, the neural lamella, and an inner layer of cells, the sheath-cells. The neural lamella has been identified as being composed of a collagen-type protein and neutral mucopolysaccharide on the evidence of its histochemical reactions and the identification of hydroxyproline by paper chromatography in a hydrolysate of the neural lamella. The sheath-cells possess large numbers of lipochondria composed of phospholipids and cerebrosides, and small spherical mitochondria. The cytoplasm also contains lipids (some of which may be cerebrosides), glycogen, and RNA.

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