Factors associated with neurocognitive test performance at baseline: a substudy of the INSIGHT Strategic Timing of AntiRetroviral Treatment (START) trial.

OBJECTIVES: We describe neuropsychological test performance (NP) in antiretroviral treatment (ART)-naïve HIV-positive individuals with CD4 cell counts above 500 cells/µL. METHODS: In a neurology substudy of the International Network for Strategic Initiatives in Global HIV Trials (INSIGHT) Strategic Timing of AntiRetroviral Treatment (START) study, eight neurocognitive tests were administered. The primary measure of NP was the quantitative NP z-score (QNPZ-8), the average of the z-scores for the eight tests. Associations of baseline factors with QNPZ-8 scores were assessed by multiple regression. Mild neurocognitive impairment (NCI) was defined as z-scores < -1 in at least two of six cognitive domains. RESULTS: A total of 608 participants had a median age of 34 years; 11% were women and 15% were black; the median time since HIV diagnosis was 0.9 years; the median CD4 cell count was 633 cells/µL; 19.9% had mild NCI. Better NP was independently associated with younger age, being white, higher body mass index (0.10 per 10 kg/m(2) higher), and higher haematocrit percentage (0.19 per 10% higher). Worse NP was associated with longer time since HIV diagnosis (-0.17 per 10 years), diabetes (-0.29) and higher Framingham risk score (-0.15 per 10 points higher). QNPZ-8 scores differed significantly between geographical locations, with the lowest scores in Brazil and Argentina/Chile. CONCLUSIONS: This is the largest study of NP in ART-naïve HIV-positive adults with CD4 counts > 500 cells/µL. Demographic factors and diabetes were most strongly associated with NP. Unmeasured educational/sociocultural factors may explain geographical differences. Poorer NP was independently associated with longer time since HIV diagnosis, suggesting that untreated HIV infection might deleteriously affect NP, but the effect was small.

A de novo mutation in KIT causes white spotting in a subpopulation of German Shepherd dogs.

Although variation in the KIT gene is a common cause of white spotting among domesticated animals, KIT has not been implicated in the diverse white spotting observed in the dog. Here, we show that a loss-of-function mutation in KIT recapitulates the coat color phenotypes observed in other species. A spontaneous white spotting observed in a pedigree of German Shepherd dogs was mapped by linkage analysis to a single locus on CFA13 containing KIT (pairwise LOD = 15). DNA sequence analysis identified a novel 1-bp insertion in the second exon that co-segregated with the phenotype. The expected frameshift and resulting premature stop codons predicted a severely truncated c-Kit receptor with presumably abolished activity. No dogs homozygous for the mutation were recovered from multiple intercrosses (P = 0.01), suggesting the mutation is recessively embryonic lethal. These observations are consistent with the effects of null alleles of KIT in other species.

Implications of self-reported cognitive and motor dysfunction in HIV-positive patients.

OBJECTIVE: The authors examined HIV-positive subjects to determine the relationship of patient complaints of cognitive and motor dysfunction to psychiatric status and performance on established cognitive and motor function tests. METHOD: HIV-positive volunteers (N = 77) were evaluated at entry into a longitudinal neurological study. Forty were asymptomatic, 29 had AIDS-related complex, and eight had AIDS. The subjects were not selected for the presence or absence of cognitive or motor complaints. Complaints of cognitive and motor dysfunction were assessed with items from the AIDS Clinical Trials Group Macro Neurologic Exam. Current depression and anxiety were assessed with the Profile of Mood States. Psychiatric status was assessed with the NIMH Diagnostic Interview Schedule, a structured interview that provides DSM-III psychiatric diagnoses. Actual cognitive and motor performance was measured with standard neuropsychological tests known to be sensitive to the effects of HIV. RESULTS: Cognitive complaints were found in 38 (49%) of the subjects. These complaints were associated with psychiatric symptoms but not with cognitive performance. Motor complaints, found in 12 (16%) of the subjects, were associated with poorer motor performance but not with psychiatric symptoms. The overall frequency of psychiatric diagnosis was high. CONCLUSIONS: Self-reports of cognitive and motor dysfunction were common in this unselected group and are of concern to health care providers. Potentially treatable psychiatric conditions were also common, particularly in subjects with cognitive complaints, and appropriate treatment referrals are indicated. Patients who report motor dysfunction should be neurologically evaluated for treatable causes.

Event-related potentials in human immunodeficiency virus infection. A prospective study.

P3 event-related evoked potentials (ERP) were recorded from 47 human immunodeficiency virus (HIV)-positive subjects examined twice and 29 HIV-positive subjects examined three times at 6-month intervals. The P3 latency significantly increased over time for asymptomatic subjects and subjects with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex. N2 latency was prolonged relative to control values in both HIV-positive groups but did not increase with time. The P3 latency correlated with neuropsychologic measures of motor control and speed of mental processing. Confounding factors (active or previous substance abuse, developmental disabilities, and history of closed head injury or epilepsy) did not significantly affect ERP latencies. Endogenous ERP components are frequently abnormal in HIV-positive subjects and the P3 latency progressively increases over time. Continued follow-up is required to determine the clinical utility of ERP studies in the HIV-positive population.

Peripheral neuropathy in a cohort of human immunodeficiency virus-infected patients. Incidence and relationship to other nervous system dysfunction.

A cohort of 94 patients infected with human immunodeficiency virus was evaluated clinically and electrophysiologically for the presence of peripheral neuropathy, and the results were compared with evaluations of central nervous system function. Thirty-two (34%) had some degree of peripheral neuropathy; 18 (19%) (six [12%] of the 49 asymptomatic patients, five [45%] of the 11 patients with acquired immunodeficiency syndrome [AIDS], and seven [21%] of the 34 patients with AIDS-related complex) had neuropathy on clinical examination; and 21 (23%) (eight [16%] asymptomatic, four [36%] AIDS, and nine [26%] AIDS-related complex) had neuropathy on electrophysiologic evaluation. There was a significant correlation between the presence of neuropathy and evidence of central nervous system dysfunction.

Vitamin B12 deficiency and nervous system disease in HIV infection.

BACKGROUND: Vitamin B12 deficiency may result in a number of neurological and neuropsychiatric disorders. Patients with human immunodeficiency virus type 1 (HIV-1) infection may have a high rate of vitamin B12 deficiency and nervous system disease. Vitamin B12 deficiency may contribute to neurological disease in HIV-1-infected individuals. OBJECTIVE: To evaluate the possible contribution of vitamin B12 deficiency to neurological disease in HIV-1-infected individuals. MAIN OUTCOME MEASURES: Comparison of serum vitamin B12 levels with neurological, neuropsychological, and mood state abnormalities in 153 HIV-1-positive subjects and 57 high-risk seronegative controls. A subgroup of 67 subjects underwent additional extensive clinical neurophysiological, cerebrospinal fluid, and magnetic resonance imaging evaluations. RESULTS: No statistically significant relationships were noted between vitamin B12 levels and abnormalities on any of the measures examined. CONCLUSIONS: This study does not indicate an important role for vitamin B12 deficiency in the neurological disease of HIV-1 infection.

The importance of confounding factors in the evaluation of neuropsychological changes in patients infected with human immunodeficiency virus.

There are conflicting reports on the early effects of human immunodeficiency virus (HIV) infection on the nervous system. Some studies have suggested that there may be early cognitive impairment, while others have refuted this. We describe the results of extensive neuropsychological testing in a group of 40 infected subjects. These indicate that the degree of impairment is closely related to confounding factors other than the infection itself. Our conclusion is that the early stages of HIV disease are not associated with a high frequency of cognitive impairment if these confounding variables are taken into consideration.

Semen preparation with the Sperm Select System versus a washing technique.

OBJECTIVE: To compare sperm migration through sodium hyaluronate with simple washing as methods for preparing sperm for IUI. DESIGN: Ten normal semen specimens were prospectively collected and samples were prepared by simple washing and by migration into sodium hyaluronate using the Sperm Select System (Select Medical Systems, Williston, VT). The semen and each treatment group were evaluated for sperm concentration, percent motile, viability, acrosomal status, longevity, and computer-aided semen analysis (CASA) parameters. SETTING: University reproductive endocrinology facility. RESULTS: The recovery of motile sperm was significantly higher for the washing method (mean +/- SEM 75% +/- 7%) than for the hyaluronate method (10% +/- 1%). The number of motile sperm recovered by migration into hyaluronate was independent of the percentage of motile sperm in the semen specimen and positively correlated with sperm concentration. The hyaluronate method produced greater percentages of motile, viable, and morphologically normal sperm, with lower proportions of premature acrosome reactions, higher sperm velocity, and greater linearity. CONCLUSIONS: The Sperm Select System method of sperm separation provides a highly uniform specimen with improved sperm quality. However, the recovery of motile sperm is considerably lower than for simple washing methods.

Calpain and calpastatin are located between the plasma membrane and outer acrosomal membrane of cynomolgus macaque spermatozoa.

Mammalian sperm must undergo an acrosome reaction prior to penetration of the zona pellucida and subsequent fusion with an oocyte. Sperm gain the capability to acrosome react after a period of capacitation, which primarily involves biochemical changes in the sperm membranes. The morphological events of the acrosome reaction have been well-documented, but the underlying cellular mechanisms that regulate capacitation and the acrosome reaction remain unclear. Antibodies to the 2 ubiquitous calpains, mu and m, as well as the small subunit, which associates with both calpains, were localized at the ultrastructural level to the region between the plasma membrane and the outer acrosomal membrane of cynomolgus macaque sperm. After the acrosome reaction, all of the anti-calpain antibodies labeled the acrosomal shroud, suggesting that calpains are located throughout the cytoplasmic area between the 2 outer sperm membranes. Calpastatin is an endogenous modulator of calpain activity and is also localized within the same cytoplasmic region as calpains. The antibodies used for ultrastructural localization were also used to probe Western blots of sperm extracts. Antibodies to either the mu- or m-calpain recognized an 80-kd protein, which is similar to the molecular weights of other ubiquitous calpains described. The small subunit (30 kd) was also recognized with a specific monoclonal antibody. An antibody to calpastatin recognized a major band at 78 kd and a lighter band at 45 kd, while the antibody to the testis-specific isoform of calpastatin (TCAST) recognized a 110-kd protein. We hypothesize that this cysteine protease system may be functional in cynomolgus macaque sperm during capacitation, the acrosome reaction, or both.

Column separation of motile sperm from stallion semen.

Subfertility in stallions is common, and methodologies are needed to increase the fertility in these animals. In other species, removal of the dead sperm from semen increases the quality and fertility of semen. With horse semen we evaluated 48 combinations of column separation techniques using micro-spin chromatography columns. The greatest improvement in motility was observed with glass wool, whereas glass beads exhibited the greatest recovery of motile sperm. Although centrifugation time did not influence recovery rate or percent motility, a column length of 2 cm was superior for recovery of motile sperm. In scale-up experiments using 2-cm columns of glass beads in 50-ml syringe barrels, centrifugation proved to be superior to gravity flow, suction, and syringe plunger as extraction methods for drawing semen through the column; however, gravity flow produced acceptable results and may be more suitable for use in a field setting. When the volume of semen for separation was increased from 10 ml to 20 ml, the recovery rate of motile sperm was also increased. Further increasing the volume of semen for separation did not improve the recovery rate, and for volumes greater than 50 ml the column had a tendency to "clog." Thus, a suitable method for column separation of equine sperm utilizes a 2-cm column of glass beads in a 50-ml syringe casing. Centrifugation is the ideal extraction method; however, gravity flow is an acceptable extraction method suited to the field setting, using a maximum semen volume of 50 ml.

Validation of an acrosomal stain for equine sperm that differentiates between living and dead sperm.

An acrosomal staining technique that can differentiate between living and dead sperm was developed for equine sperm. The fluoresceinated lectin Pisum sativum agglutinin (FITC-PSA) was used to identify the presence or absence of acrosomal contents, while the supravital nuclear dye Hoechst 33258 (H258) was used to assess viability. The accuracy of the FITC-PSA acrosomal stain was tested by comparing the percentage of sperm that had lost their acrosomal contents, detected by the staining method, with that detected by transmission electron microscopy (TEM). Following capacitation in vitro, the acrosomal status of sperm induced to acrosome react with A23187 and of control sperm were very similar with the staining technique and TEM, confirming the accuracy of the FITC-PSA acrosomal stain. We investigated the relationship between viability as measured by exclusion of H258 and motility as measured by three methods: one subjective and two objective. Although there was a good correlation between viability and motility as measured by all three methods (r = 0.88, 0.85, 0.75), there was always a proportion of viable sperm that were nonmotile. The physiology of the viable, nonmotile sperm was further investigated by comparing for individual sperm the viability as measured by exclusion of H258 with the mitochondrial function as measured by rhodamine 123. A good correlation (r = 0.99) was found to exist between viability and mitochondrial function, indicating that viable, nonmotile sperm possess functional mitochondria and confirming the ability of supravital staining to distinguish between living and dead sperm. We determined that 29-81% of the sperm in semen that had lost their acrosomal contents were in fact dead. Thus, this acrosomal staining technique can provide more relevant endpoints for future investigations of capacitation, the acrosome reaction, and sperm handling techniques in the horse.

Cerebrospinal fluid analysis in human immunodeficiency virus infection.

Cerebrospinal fluid (CSF) analytes were evaluated in 59 human immunodeficiency virus (HIV+) individuals to assess neurological involvement. Glucose, total protein, cell counts, p24 antigen, CSF: serum albumin/IgG ratios, and oligoclonal bands were measured. Eighty percent of samples showed abnormalities in one or more analyte. In some patients samples, these abnormalities could mimic those of secondary opportunistic infection when none was present. The presence of oligoclonal banding in CSF (31 percent) and disturbances in CSF: serum albumin/IgG ratio (30 percent) were related to decreases in serum CD4+ lymphocytes. Disturbances in CSF: Serum albumin/IgG ratio were also related to severity of non-neurological HIV disease staging. Cerebrospinal fluid oligoclonal bands were distinct from that found in serum in the same subjects. Since immune complexes between immunoglobulins and enzymes are observed in these same patients, these oligoclonal bands may result in artifactually elevated enzyme results secondary to decreased clearance leading to erroneous clinical decisions. There was no significant relationship between any abnormalities and the presence of neurologic disease as established by a wide variety of other studies. It is important to recognize the limits of CSF interpretation in this patient group.

Heart period variability during vagal nerve stimulation.

Vagal nerve stimulation is an emerging therapy for epilepsy, yet little is known regarding the effects of this stimulation on heart period variability. We selected 10 patients (two female, eight male) who were receiving high-frequency, high-intensity left vagal nerve stimulation for intractable epilepsy. Electrocardiogram data were recorded for a 7 min baseline, 2.5 min of stimulation and a 7 min post-stimulation period. We found no significant changes in average heart period, instantaneous changes of successive R-to-R intervals greater than 50 ms or fractal dimension. We also found no significant changes in the total power in the 0.0-0.04 Hz, 0.04-0.12 Hz and 0.2-0.4 Hz bands with stimulation of the left vagus nerve. This study suggests that left vagal nerve stimulation has little acute effect on the cardiac rhythm or heart period variability.

The effects of cryopreservation on the morphometric dimensions of caprine sperm heads.

Cryopreserved semen has been utilised in the artificial insemination of livestock species for over 40 years, even though the detrimental effects of cryopreservation on sperm function and fertility are well documented. In the present study, computer-automated sperm-head morphometry was used to determine if goat sperm-head morphometry was affected by freezing and thawing. A microscope slide was prepared from single semen samples, collected by artificial vagina, from 10 sexually active Saanen bucks. The remainder of each sample was frozen in a tris-citrate-yolk extender. After thawing, semen smears were prepared on microscope slides. All slides were stained in haematoxylin and mean sperm-head measurements of length, width, width/length, area and perimeter were determined for each slide by computer aided sperm morphometry analysis. The effects of sperm freezing on sperm-head dimensions within and among all bucks were determined. No significant (P > 0.10) freezing effect was found between fresh semen and postthaw samples for length (7.00 microns vs 7.13 microns), width (3.77 microns vs 3.87 microns), width/length (0.54 micron vs 0.54 micron), area (19.67 microns2 vs 20.57 microns2) and perimeter (18.62 microns vs 18.83 microns) when analysed across all bucks. Significant differences (P < 0.05) were however found within three bucks for area, perimeter, length and width, with the percentage increase in measurements being significantly greater than in the remaining bucks. The variability of the morphometric dimensions were not affected by freezing. The results indicate that semen freezing did not affect the overall dimensions of sperm heads across the entire population of bucks sampled. However, since sperm-head dimensions from three bucks were affected, changes in sperm-head morphometry may be indicative of spermatozoa of the semen from individuals to successfully freeze. Because the overall mean sperm-head dimensions acquired from frozen/thawed semen were not different from those of fresh semen, previously reported measurements of goat sperm heads are probably reflective of fresh semen. More importantly, retrospective studies of sperm-head morphometry and fertility may now be performed utilising extensive breeding records from frozen semen.

Inconsistent response patterns and the prediction of child maltreatment.

Inconsistent response patterns have been used with other measures to screen for child maltreatment. To date the inconsistency (IC) scale, a validity scale on the Child Abuse Potential (CAP) Inventory, has not been used as a screening criterion for physical child abuse. The present study examined the responses of 89 physical child abusers and 108 comparison subjects to determine if the CAP Inventory IC scale has any utility in the screening for physical child abuse. While results indicated the CAP Inventory IC scale scores were significantly higher for the physical child abuse group, a series of discriminant analyses indicated that the IC scale did not account for any meaningful variance after variance related to child abuse factors was removed. Further, the results indicated that dependence on the IC scale alone for physical child abuse screening purposes could be expected to produce excessive false positive and false negative classifications.

Neurocognitive effects of treatment interruption in stable HIV-positive patients in an observational cohort.

OBJECTIVE: Prior studies have shown improved neurocognition with initiation of antiretroviral treatment (ART) in HIV. We hypothesized that stopping ART would be associated with poorer neurocognitive function. METHODS: Neurocognitive function was assessed as part of ACTG 5170, a multicenter, prospective observational study of HIV-infected subjects who elected to discontinue ART. Eligible subjects had CD4 count >350 cells/mm(3), had HIV RNA viral load <55,000 cp/mL, and were on ART (>or=2 drugs) for >or=6 months. Subjects stopped ART at study entry and were followed for 96 weeks with a neurocognitive examination. RESULTS: A total of 167 subjects enrolled with a median nadir CD4 of 436 cells/mm(3) and 4.5 median years on ART. Significant improvements in mean neuropsychological scores of 0.22, 0.39, 0.53, and 0.74 were found at weeks 24, 48, 72, and 96 (all p < 0.001). In the 46 subjects who restarted ART prior to week 96, no significant changes in neurocognitive function were observed. CONCLUSION: Subjects with preserved immune function found that neurocognition improved significantly following antiretroviral treatment (ART) discontinuation. The balance between the neurocognitive cost of untreated HIV viremia and the possible toxicities of ART require consideration. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that discontinuing ART is associated with an improvement in 2 neuropsychological tests (Trail-Making Test A & B and the Wechsler Adult Intelligence Scale-Revised Digit Symbol subtest) for up to 96 weeks. Resuming ART was not associated with a decline in these scores for up to 45 weeks.

Neuropsychological abnormalities in patients with dementia in CRF 01_AE HIV-1 infection.

HIV-associated dementia (HAD) is not firmly established in patients with circulating recombinant form (CRF) 01_AE HIV-1. In this study, we compared neuropsychological performance among 15 Thai individuals with HAD, 15 Thai individuals without HAD, and 30 HIV-negative control subjects. HIV-1 participants were highly active anti-retroviral therapy naive and matched by age, education, and CD4 count. Neuropsychological testing abnormalities were identified in most cognitive domains among HAD vs HIV-negative participants, confirming the presence of HAD in CRF01_AE.

Updated research nosology for HIV-associated neurocognitive disorders.

In 1991, the AIDS Task Force of the American Academy of Neurology published nomenclature and research case definitions to guide the diagnosis of neurologic manifestations of HIV-1 infection. Now, 16 years later, the National Institute of Mental Health and the National Institute of Neurological Diseases and Stroke have charged a working group to critically review the adequacy and utility of these definitional criteria and to identify aspects that require updating. This report represents a majority view, and unanimity was not reached on all points. It reviews our collective experience with HIV-associated neurocognitive disorders (HAND), particularly since the advent of highly active antiretroviral treatment, and their definitional criteria; discusses the impact of comorbidities; and suggests inclusion of the term asymptomatic neurocognitive impairment to categorize individuals with subclinical impairment. An algorithm is proposed to assist in standardized diagnostic classification of HAND.