New insights into diabetic polyneuropathy.

Patients with complaints of numbness, tingling, and dysesthesias in the toes and feet are frequently referred to neurologists. Often, the only objective evidence for peripheral nerve dysfunction in these patients is limited to small-caliber sensory nerve fibers. On examination these patients may have reduced distal pinprick sensation, and distal leg skin biopsies show loss of small-caliber nerve fibers.

Schwann cell chemokine receptors mediate HIV-1 gp120 toxicity to sensory neurons.

Human immunodeficiency virus (HIV)-associated sensory neuropathy (HIV-SN) is the most common neurological complication of HIV infection. Currently, the pathogenesis of HIV-SN is unknown. Because there is no convincing evidence of neuronal infection, HIV neurotoxicity is likely to be effected either by secreted viral proteins such as the envelope glycoprotein gp120 or by neurotoxic cytokines released from infected/activated glial cells.

Response to systemic HIV viral load suppression correlates with psychomotor speed performance.

The authors evaluated the association of a virologic response to highly active antiretroviral therapy, or a subsequent rebound, with performance on two measures of psychomotor speed in HIV-positive subjects. Virologic suppression was associated with improved performance on measures of psychomotor speed, and virologic rebound was associated with psychomotor speed performance decline. Changes in plasma HIV viral load in HIV-positive individuals with cognitive slowing correlate with performance on tests of psychomotor speed.

Recent developments in the HIV neuropathies.

Purpose Of Review: With the introduction of highly active antiretroviral therapy peripheral neuropathies have become the most common neurological complications in HIV infection. The frequency and spectrum of these neuropathies are changing, as the various toxic and immune factors are modified by new treatment strategies. Recent studies have provided a better understanding of the risk factors, markers and relevant pathogenic mechanisms, and a thorough review of these is critical for an improved understanding of this important and increasingly common complication.

Association between the A/A genotype at the lymphotoxin-alpha+250 site and increased mortality in children with positive blood cultures.

Introduction: Tumor necrosis factor-alpha has been implicated in the hemodynamic manifestations of sepsis. Genetic polymorphisms located in the first intron of the lymphotoxin-alpha gene have been associated with increased secretion of tumor necrosis factor-alpha. We hypothesized that bacteremic children with the high secretor genotype, AA, have higher levels of tumor necrosis factor-alpha and a worse outcome.

Lamotrigine for HIV-associated painful sensory neuropathies: a placebo-controlled trial.

Objective: To evaluate the efficacy and tolerability of lamotrigine (LTG) for the treatment of pain in HIV-associated sensory neuropathies.

Methods: In a randomized, double-blind study, patients with HIV-associated distal sensory polyneuropathy (DSP) received LTG or placebo during a 7-week dose escalation phase followed by a 4-week maintenance phase. Randomization was stratified according to whether or not patients were currently using neurotoxic antiretroviral therapy (ART).

Inter-rater reliability of a clinical staging of HIV-associated cognitive impairment.

Objective: To determine the inter-rater reliability of a modification of the Memorial Sloan-Kettering (MSK) Staging for HIV-associated cognitive impairment.

Methods: Data were abstracted on neurologic, neuropsychological, and functional status on 100 individuals participating at four sites in the Northeast AIDS Dementia (NEAD) Consortium cohort study, a longitudinal study of predictors of cognitive impairment in HIV-infected individuals. Neuropsychological performance was defined 1) based on the neuropsychologist's global impression and 2) solely based on neuropsychological test scores.

Human immunodeficiency virus-associated dementia: an evolving disease.

This article reviews the changing epidemiology of HIV-associated dementia, current concepts of the different patterns of dementia under the influence of highly active antiretroviral therapy, and reviews therapeutic aspects.

Lipid composition of suspended particulate matter (SPM) in a southeastern blackwater stream.

Suspended particulate matter (SPM) was collected seasonally for 1 yr at third- and fifth-order sites in a blackwater stream on the coastal plain in South Carolina. Fatty acids with carbon chain lengths from C(12)-C(32) were the most abundant component among the lipid classes examined with total concentrations varying from 8.5 to 60.

An aromatic amino acid auxotrophic mutant of Bordetella bronchiseptica is attenuated and immunogenic in a mouse model of infection.

We have constructed an aromatic amino acid auxotrophic mutant of Bordetella bronchiseptica, harbouring mutations in aroA and trpE to investigate the use of such a strain as a live-attenuated vaccine. B. bronchiseptica aroA trpE was unable to grow in minimal medium without aromatic supplementation.

Evolutionary adaptation of a mammalian species to an environment severely depleted of iodide.

Lack of dietary iodine is associated with thyroid insufficiency and its dire consequences including cretinism, yet territories severely deficient in iodine are home to many species of wild animals. The premise of our work is that an adaptation must be in place in order to allow these animals to thrive. We collected phyllotine rodents of the genus Auliscomys from the Altiplanic region of North Chile, an area historically associated with goitre and other manifestations of iodine deficiency disorders.

Nucleoside analogues and neuropathy in the era of HAART.

Background: Sensory neuropathies occur commonly in the setting of HIV infection. Sensory neuropathy (SN) is clearly associated with HIV itself, and in this context develops in association with increased macrophage activation in the peripheral nervous system. A clinically identical SN may also occur as a consequence of exposure to some HIV treatments.

Epidermal reinnervation after intracutaneous axotomy in man.

Two distinct patterns of reinnervation occur after injury to the cutaneous nerves: regenerative growth of the injured nerve and "collateral sprouting" of neighboring intact nerves. We describe two complementary models of regrowth of transected small sensory fibers in human skin. The "incision" model uses a circular incision that transects the subepidermal plexus, resulting in Wallerian degeneration of the nerve fibers that enter the incised cylinder, leaving a defined zone of denervated dermis and epidermis.

FK506 is neuroprotective in a model of antiretroviral toxic neuropathy.

Antiretroviral toxic neuropathy is the most common neurological complication of human immunodeficiency virus infection. This painful neuropathy not only affects the quality of life of human immunodeficiency virus-infected patients but also severely limits viral suppression strategies. We have developed an in vitro model of this toxic neuropathy to better understand the mechanism of neurotoxicity and to test potential neuroprotective compounds.

Recovery of novel bacterial diversity from a forested wetland impacted by reject coal.

Sulphide mineral mining together with improperly contained sulphur-rich coal represents a significant environmental problem caused by leaching of toxic material. The Savannah River Site's D-area harbours a 22-year-old exposed reject coal pile (RCP) from which acidic, metal rich, saline runoff has impacted an adjacent forested wetland. In order to assess the bacterial community composition of this region, composite sediment samples were collected at three points along a contamination gradient (high, middle and no contamination) and processed for generation of bacterial and archaeal 16S rDNA clone libraries.

A randomized clinical trial of CPI-1189 for HIV-associated cognitive-motor impairment.

Background: CPI-1189 is a compound with antioxidant properties that blocks tumor necrosis factor-alpha (TNFalpha) effects in animal models. It has neuroprotective properties in model systems for HIV-associated neurotoxicity and thus is a candidate for neuroprotective therapy in humans with HIV-associated CNS disease.

Objective: To assess the tolerability and safety of CPI-1189 in treating HIV-associated cognitive-motor impairment.

Exposure to dideoxynucleosides is reflected in lowered mitochondrial DNA in subcutaneous fat.

Objectives: Nucleoside reverse transcriptase inhibitors (NRTIs), particularly dideoxynucleoside analogs (ddNs), used in the treatment of HIV, inhibit mitochondrial DNA polymerase gamma in vitro. Mitochondrial DNA (mtDNA) depletion is proposed as the underlying mechanism of many of the in vivo side effects of these agents. A reliable and valid laboratory test to detect this is not yet available.