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C Cobbs

Publications and source records attributed to C Cobbs.

8 recordsLinked to original sources
PubMed2001

Repetitive intrathecal injections of poliovirus replicons result in gene expression in neurons of the central nervous system without pathogenesis.

Poliovirus-based vectors (replicons) can be used for gene delivery to motor neurons of the CNS. In the current study, a replicon encoding green fluorescent protein (GFP) was encapsidated into authentic poliovirions, using established procedures. Intrathecal delivery of encapsidated replicons encoding GFP to the CNS of mice transgenic for the human poliovirus receptor did not result in any functional deficits as judged by behavioral testing. Histological analysis of the CNS of mice given a single intrathecal injection of poliovirus replicons encoding GFP revealed no obvious pathogenesis in neurons (or other cell types) within the CNS. The expression of GFP was confined to motor neurons throughout the neuroaxis; a time course of expression of GFP revealed that expression was detectable 24 hr postinoculation and returned to background levels by 120 hr postinoculation. A procedure was devised to allow repetitive inoculation of replicons within the same animal. Behavioral testing of animals that had received 6 to 13 independent inoculations of replicons revealed no functional deficits. Histological analysis of the CNS from animals that had received 6 to 13 sequential inoculations of replicons revealed no obvious abnormalities in neurons or other cell types in the CNS; expression of GFP was demonstrated in neurons 24 to 72 hr after the final inoculation of the replicon. Furthermore, there was no obvious inflammatory response in the CNS after the multiple inoculations. These studies establish the safety and efficacy of replicons for gene delivery to the CNS and are discussed with respect to use of replicons as new therapeutic strategies for spinal cord injuries and/or neurological diseases.

Animals↗
PubMed2000

The "presyrinx" state: is there a reversible myelopathic condition that may precede syringomyelia?

OBJECT: Alteration of cerebrospinal fluid (CSF) flow has been proposed as an important mechanism leading to the development of syringomyelia. We hypothesize that a "presyrinx" condition due to potentially reversible alteration in normal CSF flow exists and that its appearance may be due to variations in the competence of the central canal of the spinal cord. METHODS: Five patients with clinical evidence of myelopathy, no history of spinal cord trauma, enlargement of the cervical spinal cord with T1 and T2 prolongation but no cavitation, evidence for altered or obstructed CSF flow, and no evidence of intramedullary tumor or a spinal vascular event underwent MR imaging before and after intervention that alleviated obstruction to CSF flow. RESULTS: Preoperatively, all patients demonstrated enlarged spinal cords and parenchymal T1 and T2 prolongation without cavitation. Results of magnetic resonance (MR) imaging examinations following intervention in all patients showed resolution of cord enlargement and normalization or improvement of cord signal abnormalities. In one patient with severe arachnoid adhesions who initially improved following decompression, late evolution into syringomyelia occurred in association with continued CSF obstruction. CONCLUSION: Nontraumatic obstruction of the CSF pathways in the spine may result in spinal cord parenchymal T2 prolongation that is reversible following restoration of patency of CSF pathways. We refer to this MR appearance as the "presyrinx" state and stress the importance of timely intervention to limit progression to syringomyelia.

Adult↗
PubMed1999

Millipore filter cell block preparation: an alternative to cell block in nongynecologic specimens of limited cellularity.

The use of membrane filters to concentrate cytology specimens was first described by Seal (Cancer 1956; 9:866-868). We report on a technique in which a portion of Papanicolaou-stained Millipore filter (Millipore Corp, Bedford, MA) preparation can be converted into a paraffin block for hematoxylin-eosin (H&E) preparations and immunocytochemical analysis (ICC). Seven cases with moderate cellularity and no cell block preparation were retrieved from our cytopathology files. The specimens included: 4 pleural effusions with metastatic adenocarcinoma, and 3 FNA specimens (1 metastatic melanoma, 1 metastatic adenocarcinoma, and 1 thyroid/papillary carcinoma). The filter was removed from the slide, cut in half, and subjected to paraffin embedding in the usual fashion (postfixed in 10% neutral-buffered formalin). Four-micron-thick sections were cut onto Probe-On (Fisher Scientific, Pittsburgh, Pa) slides. ICC was performed using the avidin-biotin-peroxidase complex technique and capillary gap technology. Antibodies included CAM5.2, AE1/AE3, CEA, CD15, LCA, PanCK, S100, HMB45, and thyroglobulin. All cases showed excellent preservation of cellular morphology on H&E. ICC performed on Millipore filter cell block preparations showed specific antibody staining patterns with preservation of cellular details. All antibodies showed their specific staining patterns with clean background and lack of nonspecific staining. This technique has the following advantages: 1) offers an alternative to cell blocks in moderately cellular specimens; 2) clean background; 3) preservation of cytology specimens for future studies.

Adenocarcinoma↗
PubMed1999

The "presyrinx" state: a reversible myelopathic condition that may precede syringomyelia.

BACKGROUND AND PURPOSE: Alteration of CSF flow has been proposed to be an important mechanism leading to the development of syringomyelia. We hypothesize that a "presyrinx" condition attributable to a potentially reversible alteration in normal CSF flow exists and that its appearance may be caused by variations in the competence of the central canal of the spinal cord. METHODS: Five patients with clinical evidence of myelopathy, no history of spinal cord trauma, enlargement of the cervical spinal cord with T1 and T2 prolongation but no cavitation, evidence of altered or obstructed CSF flow, and no evidence of intramedullary tumor or a spinal vascular event underwent MR imaging before and after intervention that alleviated obstruction to CSF flow. RESULTS: Preoperatively, all patients had enlarged spinal cords and parenchymal T1 and T2 prolongation without cavitation. Results of MR examinations after intervention showed resolution of cord enlargement and normalization or improvement of cord signal abnormalities. In one patient with severe arachnoid adhesions who initially improved after decompression, late evolution into syringomyelia occurred in association with continued CSF obstruction. CONCLUSION: Nontraumatic obstruction of the CSF pathways in the spine may result in spinal cord parenchymal T2 prolongation that is reversible after restoration of patency of CSF pathways. We refer to this MR appearance as the "presyrinx" state and stress the importance of timely intervention to limit progression to syringomyelia.

Adult↗
PubMed1980

Clinical and laboratory characteristics of Achromobacter xylosoxidans infection.

Achromobacter xylosoxidans was isolated from six patients. The organism causes opportunistic infections in patients who are compromised. A. xylosoxidans is a catalase- and oxidase-positive, motile, gram-negative rod that oxidizes xylose and glucose. The organism exists in a water environment and may be confused with Pseudomonas species. Unlike pseudomonas, achromobacter has peritrichous flagella. The clinical and laboratory characteristics of A. xylosoxidans are presented.

Adolescent↗
PubMed1979

Vibrio alginolyticus infections in humans.

Two clinical isolates of Vibrio alginolyticus from New Jersey are reported, one from a mixed stump infection and the other grown in pure culture from the conjunctival discharge of a man with conjunctivitis. The biochemical characteristics and antibiotic susceptibilities of these two isolates are presented. Human infections caused by V. alginolyticus are reviewed.

Adult↗
PubMedDate not supplied

Processing liquid-based gynecologic specimens: comparison of the available techniques.

OBJECTIVE: To develop a cytopreparation protocol suitable for satisfactory processing by the AutoCyte PREP System with the gynecologic specimens collected in PreservCyt fluid for the ThinPrep machine. STUDY DESIGN: The residue of a number of gynecologic specimens collected in PreservCyt and processed by ThinPrep were processed by AutoCyte PREP. Some modifications were made in the cytopreparatory protocol in order to obtain satisfactory specimens. RESULTS: The ThinPrep and AutoCyte PREP specimens were examined independently. The results were comparable, with a high degree of concordance between the two techniques. CONCLUSION: Gynecologic specimens collected in PreservCyt and following the ThinPrep specimen collection protocol can be processed using the AutoCyte PREP System. Minor protocol modifications provided comparable diagnostic material. Additional studies are needed to explore the feasibility of this approach and fulfill the various U.S. regulatory agency requirements for the liquid-based Pap test.

Cytological Techniques↗