Biomedical subjects

J R Zunt

Publications and source records attributed to J R Zunt.

13 recordsLinked to original sources

PubMed2006

Human T-lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis: viral load and muscle tone are correlated.

Human T-lymphotropic virus type 1 (HTLV-1) infections are associated with varying degrees of HTLV-1 viral load and spasticity. Increased viral load is associated with higher risk of developing HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The authors performed a cross-sectional study of 24 people with HAM/TSP in Lima, Perú, to determine if higher HTLV-1 viral load was correlated with increased muscle tone, measured with a device providing quantitative spasticity assessment (QSA). Median HTLV-1 viral load was 17.0 copies/100 peripheral blood mononuclear cells and QSA value was 39.9 Newton-meters/radian. HTLV-1 viral load was significantly correlated with QSA value (Spearman rho = .48, P = .02), suggesting viral load may play a role in expression of symptomatic neurologic disease. Longitudinal studies are needed to determine if treatments that reduce viral load will reduce muscle tone.

Cross-Sectional Studies↗

PubMed2005

Neuroparasitic infections: nematodes.

Globalization has produced an increase in the number of people at risk for contracting parasitic infection. Central nervous system infection by nematodal parasites can be devastating. Early recognition and treatment of infection can significantly decrease morbidity of the parasitic infection, as well as the risk of secondary superinfection. The clinical presentation, diagnosis, and treatment for five of the more common nematodal infections of the nervous system--Angiostrongylus spp., Baylisacaris procyonis, Gnathostoma spinigerum, Strongyloides stercoralis, and Toxocara spp.--is reviewed.

Angiostrongylus↗

PubMed2005

Neuroparasitic infections: cestodes, trematodes, and protozoans.

Parasitic infection of the nervous system can produce a variety of symptoms and signs. Because symptoms of infection are often mild or nonspecific, diagnosis can be difficult. Familiarity with basic epidemiological characteristics and distinguishing radiographic findings can increase the likelihood of detection and proper treatment of parasitic infection of the nervous system. This article discusses the clinical presentation, diagnosis, and treatment for some of the more common infections of the nervous system caused by cestodes, trematodes and protozoans: Echinococcus spp., Spirometra spp. (sparganosis), Paragonimus spp., Schistosoma spp., Trypanosoma spp., Naegleria fowlerii, Acanthamoeba histolytica, and Balamuthia mandrillaris.

Animals↗

PubMed2005

Quantitative assessment of spasticity in human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis.

People with human T-cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) develop spasticity. The authors examined 34 patients with HAM/TSP in Perú using a device that measures tone in the gastroc-soleus-Achilles tendon unit and provides a quantitative spasticity assessment (QSA). Tone in the 34 patients was more than double that of women with asymptomatic HTLV-I infection. The device may help to track progression in HTLV-I infection.

Adult↗

PubMed2004

Human T cell lymphotropic virus type 1 infection and early neurologic development: a pilot study of 48 children.

To determine whether human T cell lymphotropic virus type 1 (HTLV-1) infection is associated with delayed neurological development, we examined 48 Peruvian children with exposure to HTLV-1 who were identified at the Instituto Materno-Perinatal. Compared with 38 HTLV-1-seronegative children, the 10 seropositive children did not have higher rates of neurodevelopmental delay. Long-term follow-up is planned.

Antibodies, Viral↗

PubMed2003

Changes in CSF and plasma HIV-1 RNA and cognition after starting potent antiretroviral therapy.

The authors assessed CSF and plasma HIV-1 RNA and neuropsychological test performance (composite neuropsychological test Z score [NPZ-4]) in 25 HIV-1-infected subjects 4 and 8 weeks after beginning potent antiretroviral therapy that included a protease inhibitor. In the 14 subjects who entered the study on no antiretroviral treatment, NPZ-4 improvement was associated with decline in CSF HIV-1 RNA at both visits (p = 0.001 and p = 0.02), and those treated with zidovudine or indinavir had greater improvement in NPZ-4 at both visits compared to those treated with other drugs (p = 0.003 and p = 0.01).

Adult↗

PubMed2003

Bioterrorism and the nervous system.

Recent events of war, terrorist attacks, and mail-borne anthrax exposure have produced increasing awareness of potential bioterrorism attacks in the United States and other parts of the world. Physicians and healthcare personnel play a key role in identifying potential bioterrorist attacks. Early recognition and preparedness for bioterrorism-associated illnesses is especially important for neurologists because most bioterrorism agents can directly or indirectly affect the nervous system. This article reviews the neurologic manifestations, diagnosis, and treatments of syndromes caused by potential bioterrorism agents, as well as the potential side effects of vaccines against some of these agents.

Anthrax↗

PubMed1999

Quantitative assessment of subclinical spasticity in human T-cell lymphotropic virus type I infection.

OBJECTIVE: To compare human T-cell lymphotrophic virus type I (HTLV-I) seropositive and seronegative women for symptoms and signs of spasticity. BACKGROUND: Infection with HTLV-I causes tropical spastic paraparesis/ HTLV-I-associated myelopathy (TSP/HAM). Certain populations, including female commercial sex workers (FSW), are at increased risk of developing this infection. Fewer than 5% of HTLV-I-seropositive persons develop TSP/HAM, which is typically associated with spasticity. METHODS: Cross-sectional study of 255 registered FSW in Callao, Perú, involving a questionnaire detailing demographics and neurologic symptoms, standard neurologic examination, quantitative assessment of spasticity (QSA) of muscle tone, and serologic testing for HTLV-I. Participants and examiners were blinded to serology results. RESULTS: On the questionnaire and neurologic examination, none of the 32 HTLV-I-seropositive or 223 seronegative women had signs or symptoms of spasticity. However, mean values on QSA were significantly higher among seropositive women (27.1 Newton-meters/radian [N-m/r]) than among seronegative women (21.6 N-m/r, p = 0.01), indicating a subclinical increase in lower extremity tone. With values of QSA divided into tertiles, and the first tertile serving as the comparison group, the odds ratio for seropositivity was 1.4 (95% confidence interval [CI] 1.0 to 2.0) in the second and 3.1 (95% CI 2.2 to 4.3) in the third tertile, after adjusting for age and place of birth. CONCLUSIONS: Although a standard neurologic evaluation could not distinguish between women with and without HTLV-I infection, QSA indicated significantly increased lower extremity tone in those with infection. Long-term follow-up will determine whether these subclinical findings in asymptomatic women progress to overt TSP/HAM.

Adult↗

PubMed1999

Cerebrospinal fluid testing for the diagnosis of central nervous system infection.

The central nervous system (CNS) is susceptible to bacterial, viral, and fungal infections, and prion diseases. Examination of the cerebrospinal fluid (CSF) is crucial in diagnosing these infections. Cerebrospinal tests may directly identify an organism and its nucleic acid and surface constituents by culture, polymerase chain reaction (PCR), or antigen detection. Alternatively, antibody to an organism may be identified in CSF by enzyme-linked immunosorbent assay (ELISA), Western blot, or complement fixation assay. This article discusses how these CSF tests are performed and addresses the sensitivity and specificity of such tests for the diagnosis of selected CNS infections.

Antibody Specificity↗

PubMed1997

Progressive multifocal leukoencephalopathy presenting as human immunodeficiency virus type 1 (HIV)-associated dementia.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disorder of the CNS that usually causes hemiparesis or hemianopsia. Dementia occurs in combination with other neurologic abnormalities. We report a human immunodeficiency virus type 1 (HIV)-infected man whose only manifestation of proven PML was dementia that was clinically indistinguishable from HIV-associated dementia.

AIDS Dementia Complex↗

PubMed1990

Repression of P element-mediated hybrid dysgenesis in Drosophila melanogaster.

Inbred lines derived from a strain called Sexi were analyzed for their abilities to repress P element-mediated gonadal dysgenesis. One line had high repression ability, four had intermediate ability and two had very low ability. The four intermediate lines also exhibited considerable within-line variation for this trait; furthermore, in at least two cases, this variation could not be attributed to recurring P element movement. Repression of gonadal dysgenesis in the hybrid offspring of all seven lines was due primarily to a maternal effect; there was no evidence for repression arising de novo in the hybrids themselves. In one of the lines, repression ability was inherited maternally, indicating the involvement of cytoplasmic factors. In three other lines, repression ability appeared to be determined by partially dominant or additive chromosomal factors; however, there was also evidence for a maternal effect that reduced the expression of these factors in at least two of the lines. In another line, repression ability seemed to be due to recessive chromosomal factors. All seven lines possessed numerous copies of a particular P element, called KP, which has been hypothesized to produce a polypeptide repressor of gonadal dysgenesis. This hypothesis, however, does not explain why the inbred Sexi lines varied so much in their repression abilities. It is suggested that some of this variation may be due to differences in the chromosomal position of the KP elements, or that other nonautonomous P elements are involved in the repression of hybrid dysgenesis in these lines.

Animals↗

PubMed1988

Spontaneous formation of compound X chromosomes in Drosophila melanogaster.

Males carrying different X chromosomes were tested for the ability to produce daughters with attached-X chromosomes. This ability is characteristic of males carrying an X chromosome derived from 59b-z, a multiply marked X chromosome, and is especially pronounced in males carrying the unstable 59b-z chromosomes Uc and Uc-lr. Recombination experiments with one of the Uc-lr chromosomes showed that the formation of compound chromosomes depends on two widely separated segments. One of these is proximal to the forked locus and is probably proximal to the carnation locus. This segment may contain the actual site of chromosome attachment. The other essential segment lies between the crossveinless and vermilion loci and may contain multiple factors that influence the attachment process.

Animals↗

PubMed1987

The influence of nonautonomous P elements on hybrid dysgenesis in Drosophila melanogaster.

An inbred line of the M' strain Muller-5 Birmingham was studied for its abilities to affect P-M hybrid dysgenesis. This strain possesses 57 P elements, all of which are apparently defective in the production of the P transposase. In combination with transposase-producing elements, these nonautonomous elements can enhance or diminish the incidence of hybrid dysgenesis, depending on the trait that is studied. Dysgenic flies that have one or more paternally-derived chromosomes with these elements partially repress the instability of the P element insertion mutation, snw; however, such flies have elevated frequencies of another dysgenic trait, GD sterility, and also show distorted segregation ratios. An explanation is presented in which all of these phenomena are unified as manifestations of the kinetics of P element activation in the germ line. The progeny of Muller-5 Birmingham females exhibit partial repression of both snw instability and GD sterility. This repression appears to involve a factor that can be transmitted maternally through at least two generations. This mode of repression therefore conforms to the pattern of inheritance of the P cytotype, the condition that brings about nearly total repression of P element activity in some strains. Models in which this repression could arise from the nonautonomous P elements of Muller-5 Birmingham are discussed.

Animals↗