Biomedical subjects

S A Schneider

Publications and source records attributed to S A Schneider.

7 recordsLinked to original sources

PubMed2006

Phenotypic homogeneity of the Huntington disease-like presentation in a SCA17 family.

We describe clinical and genetic analysis of a family with spinocerebellar ataxia 17 (SCA17) presenting with a Huntington disease-like (HDL) syndrome. Clinically diagnosed, HD is genetically heterogeneous. Differential diagnosis includes SCA17. However, SCA17 HDL presentation has been observed only sporadically or in solitary individuals within a family. HDL phenotypic homogeneity in SCA17 has not been described. SCA17 can present with a HDL syndrome in multiple family members.

Adult↗

PubMed2006

Severe tongue protrusion dystonia: clinical syndromes and possible treatment.

We describe intermittent or sustained severe involuntary tongue protrusion in patients with a dystonic syndrome. Speech, swallowing, and breathing difficulties can be severe enough to be life threatening. Causes include neuroacanthocytosis, pantothenate kinase-associated neurodegeneration, Lesch-Nyhan syndrome, and postanoxic and tardive dystonia. The pathophysiology of intermittent severe tongue protrusion remains unknown. Tongue protrusion dystonia is often unresponsive to oral drugs but may benefit from botulinum toxin injections into the genioglossus muscle. Bilateral deep brain pallidal stimulation was beneficial in two cases.

Adolescent↗

PubMed2006

Familial dopa-responsive cervical dystonia.

The authors present four cases from two unrelated families with young-onset predominant cervical dystonia with a dramatic sustained response to levodopa. Onset age was 12 years (range 9 to 15). Additional symptoms included postural hand tremor and laryngeal dystonia. Genetic testing for GTP cyclohydrolase I, tyrosine hydroxylase, and sepiapterin reductase was negative. These cases may represent new forms of dopa-responsive dystonia. Levodopa is advisable in all patients with young-onset cervical dystonia.

Adolescent↗

PubMed1996

Improved detection of varicella zoster infection with a spin amplification shell vial technique and blind passage.

BACKGROUND: Among the methods available for the diagnosis of varicella zoster virus (VZV) infections, only tissue culture yields an isolate available for antiviral susceptibility testing or pathogenesis studies. However, conventional tube tissue culture (TC) has a low sensitivity. OBJECTIVE: To increase the recovery rate of VZV in tissue culture. STUDY DESIGN: Clinical specimens submitted for VZV isolation were processed by TC and rapid shell vial (SV) techniques followed by a blind passage (BP). For SV, two incubation times and two mAbs, directed against viral-early or immediate-early antigens, were compared. RESULTS: Isolation of VZV using the SV stained at 72 h postinoculation was more sensitive (88-96%) than TC (50-67%), or the SV technique at 48 h (66-70%). It was also more rapid than TC (9.6 days). The comparison of mAbs yielded similar results in SV. Blind passage of SV at 7 days postinoculation further increased detection. CONCLUSIONS: SV combined with BP is the method of choice for VZV isolation.

Journal Article↗

PubMed1992

In vitro activities of penciclovir and acyclovir against herpes simplex virus types 1 and 2.

Penciclovir (PCV) and acyclovir are acyclic guanine analogs which inhibit herpes simplex virus (HSV) DNA polymerase. Their 50% infective doses were 0.5 to 0.8 microgram/ml for clinical isolates of HSV-1 and 1.3 to 2.2 micrograms/ml for HSV-2. Furthermore, HSV-infected cultures receiving 2-h pulses of PCV had 2- to 50-fold less HSV than acyclovir-treated cultures, consistent with the prolonged intracellular half-life of PCV triphosphate.

Acyclovir↗

PubMed1985

A simple motor controller for computer-assisted microscopy.

A very simple controller has been built which allows a laboratory computer to drive a stepping motor stage and focus axis motor of a research light microscope. Its cost is minimal; negligible in comparison to the controllers offered by the microscope manufactures. A subroutine has been written to enable the programmer to control the microscope easily. The controller has been installed in the UNC neuron reconstruction system and functions very well.

Computers↗

PubMed1985

Effect of ultraviolet B radiation on S-100 protein antigen in epidermal Langerhans cells.

Ultraviolet B (UVB) radiation has been shown to induce significant alterations in both function and surface antigen expression of epidermal Langerhans cells (ELC). In this study we investigated the effect of UVB radiation on ELC marker S-100 protein antigen (S-100 Ag) which is present in the nucleus and cytoplasm of human ELC. A total of 34 sites on 31 volunteers were exposed to 3 MED (minimal erythema dose) of UVB and biopsied at various times up to 7 days after irradiation. Skin from 9 noninjured and 7 slice-wounded subjects served as controls. The avidin-biotin-peroxidase staining technique was used to identify S-100 Ag in sections of formalin-fixed, paraffin-embedded tissue, and the numbers of stained suprabasal dendritic cells were then counted over a 200 basal cell length of interfollicular epidermis. Noninjured skin had 3.56 +/- 3.01 cells, whereas slice-wounded skin had elevated numbers (greater than 10.0 cells) at 1, 24, and 48 h after injury. Following UVB irradiation, a significant (p less than 0.001) increase in antigen-positive cells (14 +/- 3.46) was found at 1 h; this number declined to just below normal at 12 h, but by 48 h returned to and remained at preinjury levels. In contrast to previous observations of the depletion of ELC surface markers by UVB radiation, we demonstrate here that the numbers of S-100 Ag-positive ELC actually increase following comparable doses of radiation. Since this increase occurs so rapidly following both UVB irradiation and slice injury, S-100 Ag may be synthesized or unmasked within the ELC as a response to wounding of the epidermis.

Adult↗