Gracilaria bursa-pastoris (Gmelin) Silva extract attenuates ultraviolet B radiation-induced oxidative stress in human keratinocytes.

The purpose of this study was to assess the protective effects of an ethanol extract derived from the red alga Gracilaria bursa-pastoris (Gmelin) Silva (GBE) on ultraviolet B (UVB)-irradiated human HaCaT keratinocytes. GBE exhibited scavenging activity against intracellular reactive oxygen species that were induced by either hydrogen peroxide or UVB radiation. In addition, both the superoxide anion and the hydroxyl radical were scavenged by GBE in cell-free systems. GBE absorbed light in the UVB range (280-320 nm) of the electromagnetic spectrum and lessened the extent of UVB-induced oxidative damage to cellular lipids, proteins, and DNA. Finally, GBE-treated keratinocytes showed a reduction in UVB-induced apoptosis, as exemplified by fewer apoptotic bodies. These results suggest that GBE exerts cytoprotective actions against UVB-stimulated oxidative stress by scavenging ROS and absorbing UVB rays, thereby attenuating injury to cellular constituents and preventing cell death.

Effects of prolonged intensive training on the resting levels of salivary immunoglobulin A and cortisol in adolescent volleyball players.

AIM: Concerns have been raised regarding the effects of prolonged intensive training on adolescent athletes. This study investigated the differences in mucosal immune functions and stress responses between intensively trained male adolescent volleyball players and age-matched sedentary controls. METHODS: Twelve male volleyball players (16.5 [0.7] years of age) and sixteen healthy sedentary male volunteers (17.1 [0.6] years of age) participated in this study. Volleyball players were engaged in regular and year-round training. Unstimulated saliva samples were collected from volleyball players during the high-intensity training period and from the counterparts at the same timepoints after at least 18 hours of rest. Concentrations of salivary total protein, secretory immunoglobulin A (SIgA), cortisol, and lactoferrin were measured. RESULTS: Results of this study revealed that the SIgA concentrations and the ratio of SIgA/total protein in volleyball players were significantly lower compared with those in sedentary controls. However, the salivary cortisol concentrations and the ratio of cortisol/total protein in volleyball players were markedly higher compared with those in sedentary controls. No significant difference was observed in lactoferrin levels between volleyball players and sedentary controls. CONCLUSION: The findings of this study suggest that the prolonged intensive training may elicit a sustained stress and induce a suppressive effect on mucosal immunity in regularly and intensively trained adolescent athletes.

Impact of intense training and rapid weight changes on salivary parameters in elite female Taekwondo athletes.

The aim of this study is to examine the cumulative effects of prolonged intensive training with or without rapid weight changes (RWC) on salivary parameters of elite female Taekwondo (TKD) athletes. Ten elite female Taiwanese TKD athletes (ages: 21.3 ± 1.2 years of age, Ht 164.4 ± 5.6 cm) volunteered to participate in this study. Resting saliva samples were collected at 28-, 14-, 7-, and 1 day before and 1-, 7-, 21 days after a national competition. The levels of salivary immunoglobulin A (sIgA), cortisol, and lactoferrin were measured. In analyzing the anthropometric data, we found that a significant proportion (50%) of elite female TKD athletes had RWC shortly before and after a national competition. The participants were allocated either to the RWC or to the non-RWC group according to their weight change profiles. Our results showed that levels of sIgA and cortisol of athletes with RWC were significantly modulated during the study period. However, athletes without RWC only showed reduced lactoferrin after competition. The results presented here demonstrate that intensive training in combination with RWC affects the mucosal immunity and disrupts the cortisol stress response of elite female TKD athletes.

Anterior cricoid split procedure with transposition of cricoid cartilage segment.

OBJECTIVE: In order to improve the outcome and to reduce the post-operative care burden following the anterior cricoid split procedure, we modified the procedure to involve splitting only the cricoid cartilage, not the mucosa deep to the cartilage. In addition, we transposed the cricoid cartilage segment after division of the cricoid ring in the midline. CASE REPORT: We present the use of our modification in a 19-month-old boy with early-stage subglottic stenosis. RESULTS: The technique was performed in one surgical field, and the graft material obtained had the same thickness as the cricoid cartilage. Because there was no intraluminal break, this procedure allowed the patient to avoid the complications of prolonged stenting, and resulted in more rapid extubation. CONCLUSION: The anterior cricoid split procedure with transposition of the cricoid cartilage segment may be a useful treatment option for early-stage subglottic stenosis, with improved outcomes and a reduced post-operative care burden.

Identification and characterization of mutations underlying Sanfilippo syndrome type A (mucopolysaccharidosis type IIIA).

Sanfilippo syndrome type A (mucopolysaccharidosis type IIIA; MPS IIIA) is caused by a deficiency of the lysosomal enzyme haparan N-sulphatase (NS). The genomic DNA segments of the NS gene from two Chinese patients with MPS IIIA were amplified by polymerase chain reaction, followed by DNA sequencing to study the molecular lesions. Four mutations (i.e. N42K, D235N, P293S and R377C) and five polymorphisms (i.e. IVS2-72A --> G, IVS2-26T --> C, IVS5+17C --> T, IVS5-37GC --> CTGT and R456H) were identified. Transfection of COS-7 cells with cDNA mutagenized to the corresponding mutations did not yield active enzyme, demonstrating the deleterious nature of the mutations. Western blot analysis revealed a 62-kDa precursor and 56-kDa mature forms for cells transfected with wild-type and polymorphic R456H enzymes. For cells transfected with mutant enzymes, the reduction in precursor and mature forms suggests an increased degradation of the mutant enzymes. The polymorphic DNA haplotype of the NS gene was analysed in 52 unrelated subjects. All five polymorphisms were in Hardy-Weinberg equilibrium. The strong non-random association among the five polymorphisms suggests little or no recombination in the NS gene.

Antiplatelet effect of 2-chloro-3-(4-acetophenyl)-amino-1,4-naphthoquinone (NQ301): a possible mechanism through inhibition of intracellular Ca2+ mobilization.

The effects of 2-chloro-3-(4-acetophenyl)-amino-1,4-naphthoquinone (NQ301), an antithrombotic agent, on aggregation, binding of fibrinogen to glycoprotein (GP)IIb/IIIa complex and intracellular signals were investigated using human platelets. NQ301 significantly inhibited the collagen-, thrombin-, arachidonic acid-, thapsigargin- and calcium ionophore A23187-induced aggregation of washed human platelets with IC50 values of 13.0+/-0.1, 11.2+/-0.5, 21.0+/-0.9, 3.8+/-0.1 and 46.2+/-0.8 microM, respectively. NQ301 also significantly inhibited FITC-conjugated fibrinogen binding to human platelet surface GPIIb/IIIa complex, but failed to inhibit the fibrinogen binding to purified GPIIb/IIIa complex. These data demonstrate that NQ301 inhibits platelet aggregation by suppression of the intracellular pathway, rather than by direct inhibition of fibrinogen-GPIIb/IIIa complex binding. NQ301 significantly inhibited the increase of cytosolic Ca2+ concentration and ATP secretion, and also significantly increased platelet cAMP levels in the activated platelets. These results suggest that the antiplatelet activity of NQ301 may be mediated by inhibition of cytosolic Ca2+ mobilization, enhancement of cAMP production and inhibition of ATP secretion in activated platelets.

CNS cholinergic innervation to the hippocampus in the rat using pseudorabies virus as a neurotracer.

The hippocampus is a central area of the memory-related neural system. Combined immunohistochemistry against choline acetyl transferase and retrograde transneuronal labelling of the pseudorabies virus were used to identify cholinergic neurons in the central nervous system projecting to the hippocampal formation of the rat. Five to ten microL of Bartha strain of pseudorabies virus were injected into the dentate gyrus, CA1 and CA3 of the hippocampus of 20 Sprague Dawley rats using stereotaxic instrument. Forty eight to 96 hr after the injection, the brains were removed and the tissue sections were processed for double immunofluorescence procedure using polyclonal antibodies against pseudorabies virus or choline acetyl transferase. The double labelled neurons were distributed at several different nuclei and the labelling patterns of three different areas of the hippocampus were similar. These data suggests that the cholinergic innervation to the hippocampus were distributed in a transsynaptic manner throughout the whole brain area.

Cutaneous nerve degeneration induced by acrylamide in mice.

Acrylamide is a neurotoxin producing distal axonopathy. Previous studies mainly focused on large-diameter motor and sensory nerves, and the influences of acrylamide neurotoxicity on small-diameter sensory nerves in the skin remained elusive. We investigated skin innervation in mice intoxicated by acrylamide. Small-diameter sensory nerves in the skin degenerated after acrylamide intoxication. Epidermal nerve swelling was the earliest sign of acrylamide intoxication, with 29.5+/-2.4% of swollen epidermal nerves in the initial stage (P<0.001). There was a trend of progressive loss of epidermal nerves with a significantly reduced epidermal nerve density in the late stage (P<0.003). In the mean time, degenerating dermal nerves exhibited a beaded appearance. These results suggest the scenario of small-diameter cutaneous nerve degeneration in acrylamide neurotoxicity: beginning with epidermal nerve terminal swelling in the initial stage and resultant epidermal nerve depletion in the late phase.

Age-dependent acrylamide neurotoxicity in mice: morphology, physiology, and function.

Acrylamide intoxication produces peripheral neuropathy characterized by weakness and ataxia in both humans and experimental animals. Previous studies on animals of different ages and species indicate that the longest and largest nerves are affected earlier with the major pathology in the terminal parts of axons, i.e., distal axonopathy. However, several issues have remained elusive; for example, what are the earliest pathological changes? An equally intriguing question is whether younger animals are more susceptible to acrylamide than older animals. To address these issues, we compared the vulnerability to acrylamide of 3- and 8-week-old mice. These mice were intoxicated with acrylamide in drinking water (400 ppm). The sequence of intoxication could be categorized into three stages. In the initial stage, there was no visible weakness or ataxia. The only noticeable changes were poor performance on the rota-rod test and swelling of motor nerve terminals. Obvious weakness and ataxia of hindlimbs developed gradually (here designated as the early stage). The weakness and ataxia progressed at variable speeds in mice of different ages, and eventually the forelimbs (quadriparesis) were affected in the late stage. Each stage appeared earlier in 3-week-old mice than in 8-week-old mice (7.1 +/- 1.1 vs 15.6 +/- 4.0 days, P < 0.01 for the early stage; and 15.3 +/- 2.1 vs 31.7 +/- 6.0 days, P < 0.01 for the late stage). The progression of neurological deficits was also faster in the younger mice (7.2 +/- 1.8 vs 16.3 +/- 4.2 days, P < 0.01). Pathological changes in the distal parts of motor nerves innervating hindfoot muscles were evaluated by combined cholinesterase histochemistry and immunocytochemistry for neuronal markers to demonstrate motor nerve terminals and neuromuscular junctions simultaneously. In the initial stage, there was axonal swelling in motor nerve terminals. As acrylamide intoxication continued, axonal swelling extended into junctional folds and into the intramuscular nerves, which resulted in Wallerian-like degeneration. Our results indicate that younger mice show a much higher susceptibility to acrylamide intoxication, and pathological changes precede neurological symptoms.

Skin Innervation and Its Effects on the Epidermis.

Sensory innervation of the skin subserves protective sensations for the body to prevent thermal and noxious injuries. Neurophysiologically, they belong to the categories of Adelta and C fibers, usually with caliber less than one micro m in diameter. Morphological demonstration of the terminals of these nerves in the epidermis has been recognized recently by sensitive immunocytochemistry and an axonal marker, the protein gene product 9.5 (PGP). PGP is a ubiquitin C-terminal hydrolase, which is abundantly present in the nervous system, and particularly enriched in the unmyelinated nerves. Sensory nerves positive for PGP arise from the dorsal root ganglion, pass through the dermis, parallel the epidermis-dermis border, penetrate the basement membrane, move vertically and upwards in the epidermis with tortuous course and knobby appearance, and finally terminate at the granular layers of the epidermis. In rodents, denervation of the skin results in degeneration of epidermal nerves within 48 h of nerve transection, and thinning of the epidermis. In humans, application of this technique to evaluate disorders of the peripheral nervous system makes study of the degeneration of sensory nerve terminals possible. Patients with sensory neuropathy had fewer epidermal nerves than normal subjects, consistent with the notion of distal axonopathy. This approach has the potential to evaluate human sensory neuropathy in temporal and spatial domains. In addition, the influences of epidermal denervation open a new field to explore the interactions between sensory nerves and keratinocytes.