In Vivo Evaluation of White Matter Abnormalities in Children with Duchenne Muscular Dystrophy Using DTI.

BACKGROUND AND PURPOSE: Duchenne muscular dystrophy is an X-linked disorder characterized by progressive muscle weakness and prominent nonmotor manifestations, such as a low intelligence quotient and neuropsychiatric disturbance. We investigated WM integrity in patients with Duchenne muscular dystrophy using DTI. MATERIALS AND METHODS: Fractional anisotropy and mean, axial, and radial diffusivity (DTI measures) were used to assess WM microstructural integrity along with neuropsychological evaluation in patients with Duchenne muscular dystrophy (n = 60) and controls (n = 40). Exon deletions in the DMD gene were confirmed using multiplex ligation-dependent probe amplification. Patients were classified into proximal (DMD Dp140+) and distal (DMD Dp140-) subgroups based on the location of the exon deletion and expression of short dystrophin Dp140 isoform. WM integrity was examined using whole-brain Tract-Based Spatial Statistics and atlas-based analysis of DTI data. The Pearson correlation was performed to investigate the possible relationship between neuropsychological scores and DTI metrics. RESULTS: The mean ages of Duchenne muscular dystrophy and control participants were 8.0 ± 1.2 years and 8.2 ± 1.4 years, respectively. The mean age at disease onset was 4.1 ± 1.8 years, and mean illness duration was 40.8 ± 25.2 months. Significant differences in neuropsychological scores were observed between the proximal and distal gene-deletion subgroups, with more severe impairment in the distal-deletion subgroup (P < .05). Localized fractional anisotropy changes were seen in the corpus callosum, parietal WM, and fornices in the patient subgroup with Dp140+, while widespread changes were noted in the Dp140- subgroup. The Dp140+ subgroup showed increased axial diffusivity in multiple WM regions relative to the Dp140- subgroup. No significant correlation was observed between clinical and neuropsychological scores and diffusion metrics. CONCLUSIONS: Widespread WM differences are evident in patients with Duchenne muscular dystrophy relative to healthy controls. Distal mutations in particular are associated with extensive WM abnormalities and poor neuropsychological profiles.

Finger clubbing: do we require digital index quantitator?

Some diseases may underlie finger clubbing. However, there is a dearth of information about early stage of finger clubbing because only few researchers have shown interest in it. We determined the Digital Index of normal, healthy subjects by using thread and manual Vernier calipers, the time used for the procedure, and its interrater reliability. The value of Digital Index was 8.86 ± 0.29 (Mean ± SD) with a range of 8.15 to 9.41. Interrater reliability was excellent with Pearson's correlation coefficient of 0.966. Overall, the time taken to measure the Digital Index ranged from 21.93 to 68.80 minutes with an average of 35.97 ± 9.16 (Mean ± SD). Determining Digital Index need much time, but this can be overcome if we use Digital Index Quantitator (DIQ). Availability of DIQ in the hospital wards will be of much benefit. DIQ can also be used to accurately quantify the progression or regression of the clubbing process. This article proves that we need morphometry of digital clubbing as well as the correlation of the physical sign of clubbing with Digital Index.

The Thomas Repair of the strangulated femoral hernia - one skin incision for all.

Several methods of femoral hernia repair have been described. It is the one most likely to strangulate, its repair must often be accompanied by examination of, and sometimes resection of, bowel or omentum. We describe a new method to repair such a hernia.

Immunotoxicology: hazard identification and risk assessment.

In summary, immunotoxicology is a relatively new science that can be defined as the study of the consequences of exposure to drugs, chemicals, and environmental toxicants on the structure and function of the immune system. Laboratory animal studies over the last 20 years have clearly demonstrated as association between suppressed immune function and altered host defense. Furthermore, rodent-based screening approaches, even with their limitations, have been reasonably successful and have added to this knowledge base. The challenges for the future lie in using these data to design better prospective human exposure studies and to improve the basis for immunotoxicology risk assessment.

The influence of vehicle gavage on seasonality of immune system parameters in the B6C3F1 mouse.

Seasonal hyporesponsiveness and other immune system variations were observed in female B6C3F1 mice during routine screening tests for immunomodulation. In a retrospective assessment, 4 years of data from over 1200 naive, vehicle, and immunosuppressed (cyclophosphamide-treated) control mice were compiled and analyzed for uniformity and significant circannual pattern of immune response. Endpoints included body, spleen, and thymus weights and an immunotoxicity assessment which enumerates specific antibody plaque-forming cells (PFC) in the spleen following immunization with sheep red blood cells. Dosing vehicles were water, corn oil, or 1% methyl cellulose instilled by oral gavage in a 5-20 ml/kg volume once daily for 5 days. Four days later, terminal organ and body weights were recorded and PFC were quantitated. Upon analysis, individual datapoints were arrayed in consistent circannual and seasonal patterns. In naive mice, the yearly peak response in circannual rhythm (acrophase) for body weight and PFC parameters occurred in the summer, with acrophases for spleen and thymus weights located in the spring. Vehicle gavage modulated the circannual/seasonal means and acrophases of all measured endpoints in distinct patterns which varied by vehicle. Body weight was the endpoint least affected by vehicle treatment. Corn oil was the vehicle resulting in the most dramatic effects on natural rhythm. As expected, the naive mice receiving an ip injection of cyclophosphamide exhibited significant decreases (p

Satisfaction with facial appearance among subjects affected by a cleft.

OBJECTIVE: This study examined the satisfaction of patients with clefting and their parents with facial appearance and how this alters with age. The relationship between satisfaction with appearance and psychosocial functioning was also examined. DESIGN: Prospective SETTING: Subjects were recruited for the study from nine hospital-based clinics. PARENTS, PARTICIPANTS: All subjects has some type of cleft and were 10, 15 or 20 years of age. In all, 111 subjects with clefting and 62 parents were included. MAIN OUTCOME MEASURES: Facial appearance was rated on a subjective ordinal scale of 1 to 7; psychosocial adjustment was measured with the Childhood Experience Questionnaire. RESULTS: Self-satisfaction with appearance among the 10- and 15-year-old subjects correlated with their psychosocial adjustment (p = .027). The 20-year-old subjects were, on average, significantly more satisfied with their appearance than the 10- and 15-year-olds (p = .009 and p = .012, respectively). However, some 20-year-old subjects remained greatly dissatisfied with aspects of their facial appearance. Subjects with visible anomalies were significantly more dissatisfied with their appearance than subjects with invisible anomalies (p = .035). The 15-year-old subjects were identified as being significantly more dissatisfied with appearance than their parents (p = .005). CONCLUSIONS: Subjects affected by a cleft with visible impairments are more dissatisfied with their facial appearance than are subjects with invisible impairments. Satisfaction with facial appearance among 10- and 15-year-old subjects with a cleft may be associated with their self-reported levels of psychosocial functioning. Measuring self-satisfaction with appearance may help to identify subjects at risk from adjustment problems.

In vitro exposure to peptidic delta opioid receptor antagonists results in limited immunosuppression.

Previous studies by our group have demonstrated that in vitro exposure to delta-opioid receptor agonists results in a significant immunostimulation, whereas in vitro exposure to non-peptidic delta-opioid receptor antagonists results in significant suppression of various immune functions. The present study assessed potential immunomodulation by the peptidic delta-opioid receptor antagonists TIPP, D-TIPP, and ICI 174864 using a panel of in vitro immune function assays. Splenocytes from female B6C3F1 mice were cultured with the peptides at concentrations of 0.00001-10 microM. B cell proliferation was quantified following cellular activation, T cell function was assessed by cytokine production following stimulation with anti-CD3 monoclonal antibody, natural immunity was assessed by quantitating natural killer (NK) cell activity following a 24-h exposure, and macrophage function was assessed by quantification of interleukin-6 (IL-6) production. None of the peptides examined significantly affected B cell proliferation. Production of IL-2 by T cells was not consistently affected by exposure to either TIPP or D-TIPP, but was significantly suppressed at 10 microM ICI 174864. Production of IL-4, however, was significantly suppressed by low concentrations of either TIPP or D-TIPP, and by 10 microM ICI 174864. IL-6 production by macrophages was unaffected except for sporadic incidents of enhanced production in cells exposed to ICI 174864. NK cell function exhibited a differential pattern of suppression, with the greatest degree of suppression observed following exposure to TIPP and only slight suppression in cells exposed to either D-TIPP or ICI 174864. These data suggest that peptidic delta-opioid receptor antagonists do not exhibit the same pattern or degree of immunosuppressive activity as the non-peptidic antagonists at equivalent in vitro concentrations.

Immune function and host defense in rodents exposed to 60-Hz magnetic fields.

This study was conducted to evaluate the influence of subchronic exposure to pure, linearly polarized 60-Hz magnetic fields (MF) on the host immune response in mice. The experimental design was as follows: three groups were exposed continuously (18.5 hr/day) to MF at field strengths of 0.02, 2, or 10 gauss (G), one group was exposed intermittently (1 hr on/1 hr off) to MF at a field strength of 10 G, and one group served as a sham control. Experimental endpoints included spleen and thymus weights and cellularity, antibody-forming cell (AFC) response, delayed-type hypersensitivity (DTH) response, splenic lymphocyte subset analysis, susceptibility to infection with Listeria monocytogenes, and natural killer (NK) cell activity. No differences in body weight, lymphoid organ weight, or lymphoid organ cellularity were observed in any MF-exposed group in comparison to sham controls. Likewise, no statistically significant differences were found in comparisons of AFC responses. Isolated statistically significant differences from control were observed in MF-exposed mice in the DTH assay, although no clear dose-related pattern of altered activity was seen. Splenic lymphocyte subset parameters examined were within normal limits in all groups, and no differences between control and MF-exposed mice were found. Host resistance to bacterial infection was not altered at any MF exposure examined in this study. Finally, although apparently dose-related, statistically significant alterations were observed in an initial study of NK cell function, repeat studies failed to demonstrate a consistent pattern of alteration.

Effects of chronic administration of 7-benzylidene-7-dehydronaltrexone and naltriben on the antinociceptive actions of delta 1- and delta 2-opioid receptor agonists.

The effects of chronic administration of 7-benzylidene-7-dehydronaltrexone, a delta 1-opioid receptor antagonist and naltriben, a delta 2-opioid receptor antagonist, on the antinociceptive responses to [D-Pen2, D-Pen5] enkephalin and [D-Ala2, Glu4]deltorphin II, delta 1- and delta 2-opioid receptor agonists, respectively, were determined in the mouse. Female B6C3F1 mice were given 7-benzylidene-7-dehydronaltrexone (3 mg/kg/day), naltriben (1 mg/kg/day) or the vehicle by subcutaneously implanted Alzet osmotic minipumps for 7 days. Both [D-Pen2, D-Pen5]enkephalin and [D-Ala2, Glu4]deltorphin II administered intracerebroventricularly (i.c.v.) produced antinociceptive as measured by the tail-flick test with ED50 values of 6.76 and 6.68 micrograms/mouse, respectively. Chronic administration of 7-benzylidene-7-dehydronaltrexone lowered the ED50 of [D-Pen2, D-Pen5]enkephalin but not of [D-Ala2, Glu4]deltorphin II. Chronic administration of naltriben lowered the ED50 of [D-Ala2, Glu4]deltorphin II but had no effect on the ED50 of [D-Pen2, D-Pen5]enkephalin. The binding of [3H][D-Pen2, D-Pen5]enkephalin to whole brain membranes of chronic 7-benzylidene-7-dehydronaltrexone-treated mice did not differ from chronic vehicle-treated mice. On the other hand, chronic administration of naltriben resulted in slight but reproducible elevation in the Bmax value of [3H][D-Pen2, D-Pen5]enkephalin to bind to whole brain membranes in comparison to vehicle-injected controls. The results suggest that chronic treatment with delta 1- and delta 2-opioid receptor antagonist cause behavioral supersensitivity to their agonists, respectively, and provides further evidence for the existence of delta-opioid receptor subtypes.

Cellular immune function in mice tolerant to or abstinent from l-trans-delta 9-tetrahydrocannabinol.

The effects of tolerance to l-trans-delta 9-tetrahydrocannabinol (THC) following repeated administration and of subsequent abstinence following drug withdrawal on the cellular immune function were determined in female B6C3F1 mice. Mice were injected with THC (10 mg/kg s.c.) twice daily for 4 days. On day 5, analgesic response to various doses of THC was determined using the tail flick test. Similarly, hypothermic response to THC was also determined. Multiple injections of THC resulted in the development of tolerance to both the analgesic and hypothermic effects of THC. Immune function studies were performed on mice rendered tolerant to or abstinent from THC by these procedures. Neither tolerance nor abstinence subsequent to a 4-day THC administration had any effect on either body weight or thymus weight and cellularity, although both spleen weight and cellularity were decreased in THC-abstinent animals. Likewise, no significant effects on B cell proliferation were observed in either tolerant or abstinent mice. The production of the cytokine interleukin-2 by T helper cells was markedly suppressed in both tolerant and abstinent mice, whereas the production of interleukin-4 was significantly suppressed only in THC-abstinent mice. Significant suppression of tumor cell cytolysis mediated by cytotoxic T cells and natural killer cells was only observed in THC-abstinent mice. These results suggest that THC-mediated modulation of the immune response may result from a differential effect on cellular populations.

A comparative study of immunomodulation produced by in vitro exposure to delta opioid receptor agonist peptides.

The present study assessed the direct immunomodulatory effect of a panel of synthetic peptides exhibiting delta-opioid receptor agonist activity. Murine splenic lymphocytes and peritoneal macrophages were cultured in vitro with peptides at concentrations of 0.00001-10 microM. Assessment was made of B-cell function by quantitating cellular proliferation, T-cell function by measuring cytokine production, natural immunity by quantitating basal and cytokine-augmented natural killer (NK) cell activity, and macrophage function by production of IL-6. These peptides had minimal effects on B-cell proliferation at any concentration examined. In comparison, enhancement of cytokine production by T-helper cells occurred following exposure to several of the compounds, to a significant extent with DPDPE, DPDPE-trifluoroacetate, or deltorphin-1 and most pronounced at concentrations between 0.00001 and 0.1 microM. Likewise, IL-6 production by macrophages was significantly augmented by exposure to these three peptides. NK cell function was significantly enhanced by in vitro exposure to several of the peptides, with enhancement generally noted at concentrations between 0.00001 and 0.01 microM. However, some of the peptides (most notably DADLE) greatly suppressed NK cell activity. These data suggest that delta opioid agonists are broadly immunomostimulatory.

Pesticide-induced immunotoxicity: are Great Lakes residents at risk?

Several organophosphate and organochlorine compounds, including pesticides commonly found in the Great Lakes basin, have the potential to induce immunotoxicity. Because of biomagnification and accumulation in the food chain, Great Lakes residents may inadvertently be exposed to these compounds and thus face increased risk of immune dysfunction. In spite of the laboratory animal data and evidence from occupational exposures that suggest immunotoxicity, there is no definitive evidence as yet that environmental exposure to these xenobiotics poses a significant threat to the human immune system that is sufficient to predispose residents of the Great Lakes basin to increased disease. However, uncertainties with regard to exposure levels, predictability of tests, suitability of the animal models, and immune reserve cannot be ruled out when making risk assessment decisions such as this.

Local versus systemic immunotoxicity of isobutyl nitrite following subchronic inhalation exposure of female B6C3F1 mice.

Female B6C3F1 mice were exposed to isobutyl nitrite (IBN) by inhalation at 0, 37.5, 75, or 150 ppm for 6 hr per day, 5 days per week for 15 weeks. The potential of this compound to induce immunotoxicity was assessed during the 3rd, 13th, 14th, and 15th week of exposure and after 2 weeks of recovery following the 15 weeks of exposure. Both systemic and lung immune functions were examined, including body and lymphoid organs weights, pulmonary macrophage function and host defense, expression of splenic lymphocyte cell-surface markers, natural killer cell function, mixed lymphocyte reaction, and induction of specific antibody to a T-cell-dependent antigen. There was a dose-related suppression of T-cell-dependent antibody-forming cell responses in the spleen following IBN exposure; however, other measures of T-cell and nonspecific immunity were not significantly affected. A dose-related increase of H202 production by alveolar macrophages was present after 12 but not after 68 exposures to IBN. In contrast, pulmonary host defense mechanisms against Klebsiella pneumoniae were unaffected. These results suggest that in the absence of changes in host resistance, IBN may have selective and partially reversible effects on the immune system.

Suppression of immune function by non-peptidic delta opioid receptor antagonists.

Previous studies in this laboratory and elsewhere have provided evidence that compounds acting as delta opioid receptor agonists exhibit marked immunostimulatory potential. Conversely, the delta opioid receptor antagonists have previously been shown to demonstrate immunosuppressive effects as assessed by proliferation of T-cells following allogeneic or xenogeneic stimulation. The present study was performed to further characterize this immunosuppressive activity using the compounds benzylidene naltrexone (BNTX), naltrindole (NTI), and naltriben (NTB). In vitro exposure to BNTX resulted in an apparent dose-related suppression of B-cell proliferation, cytokine production by T-helper cells, and natural killer (NK) cell activity, with statistically significant suppression observed at concentrations between 1 and 10 microM. NTI was also immunosuppressive for all immune function parameters examined, although this compound was less active than BNTX. In vitro exposure to the structurally related compound NTB had no significant effect on any immune function examined in this study. In all cases, immunosuppression occurred in the absence of any detectable alteration in cellular viability, suggesting a specific immunosuppressive effect rather than overt toxicity.

Effects of naltrexone on morphine-induced tolerance and physical dependence and changes in cellular immune function in mice.

The effects of naltrexone on tolerance/dependence, as well as alterations in cellular immune function induced by morphine administration, were determined. Mice were rendered tolerant to and physically dependent on morphine by subcutaneous implantation of pellets containing 75 mg of morphine. Implantation of naltrexone pellets (10 mg) blocked the development of tolerance to the analgesic action of morphine, as well as the development of physical dependence. Morphine suppressed lymphoid organ weights and cellularities, and this suppression was blocked by naltrexone. B-Cell proliferation was suppressed in morphine-tolerant but not in morphine-abstinent mice, and this suppression was exacerbated by naltrexone. Morphine tolerance and abstinence were associated with suppression of IL-2 production, which was completely blocked by naltrexone. NK cell activity was not significantly affected by either morphine or naltrexone exposure. The results suggest that the effects of morphine on the immune system are at least partially mediated through opioid receptors.

Immunotoxicologic effects of ethylene dibromide in the mouse and their modulation by the estrous cycle.

Estrous cycle modulation of immunologic sensitivity to ethylene dibromide (EDB) was studied in addition to toxicologic end points. Female B6C3F1 mice were injected intragastrically with 31.25, 62.5, or 125 mg/kg EDB for 5 days a week for 12 weeks. Vaginal smears determined the estrous cycle. At 125 mg/kg there were decreases in hemoglobin and hematocrit and longer estrous cycles (5.5 vs 4.3 days, p = 0.006), and increases in cholesterol, triglycerides, total protein, and albumin. The negative dose response seen for T- and B-cell mitogenesis around metestrus was absent for mice near estrus. The high dose of EDB prolonged intervals between estrus, was immunotoxic and immunosuppressive.

Comparison of the hallucinogenic indole alkaloids ibogaine and harmaline for potential immunomodulatory activity.

The immunomodulatory potential of the indole alkaloids ibogaine and harmaline was examined in a panel of in vitro immune function assays. These assays were chosen to assess T-cell regulatory and effector function, B-cell function, macrophage function, and natural killer-cell function. The in vitro exposure to either ibogaine or harmaline resulted in a dose-related suppression of all immune functions examined except macrophage function. This suppression was noted at various concentrations in different assays, but was generally only associated with high concentrations (10-100 mumol/l).

In vitro evaluation of fentanyl and meperidine for immunomodulatory activity.

Exposure to drugs, either ethical pharmaceuticals or illicit street drugs, often results in medical complications, including alterations in the immune system. Among the drugs associated with immunomodulatory potential are the analgesics fentanyl and meperidine. The purpose of this study was to determine the potential of these drugs to alter immunological parameters subsequent to in vitro exposure at a range of concentrations. This potential immunotoxicity was assessed using a series of in vitro assays measuring B-lymphocyte proliferation, cytokine production by T-helper lymphocytes, T-lymphocyte cytolytic function, natural killer (NK) cell function, and macrophage function. Exposure to these analgesics was associated with a differential suppression of interleukin-4 production by T-cells, as well as a more generalized suppression of cytokine production by macrophages. In addition, T-cell cytolytic activity was suppressed at high drug concentrations. B-cell proliferation and NK cell activity were also inhibited, but to a lesser degree than noted with T-cell function. Addition of naltrexone to the cultures did not reverse these alterations in immune function, suggesting that these changes are not mediated via opioid receptors.