Comparative ultrasonographic evaluation of the Achilles paratenon in symptomatic and asymptomatic subjects: an imaging study.

Achilles tendon analysis represents one of the most frequently requested ultrasonographic evaluations, due to the high incidence of tendinopathy. Various authors have described inflammatory features of the paratenon recruited 22 subjects complaining of pain in the mid-portion of the Achilles tendon and 22 healthy subjects. Both groups underwent ultrasonographic examination and Victorian Institute of Sport Assessment-Achilles questionnaire administration. It was found statistically significant inter-group differences of the paratenon (p = 0.0001) as well as tendon thickness (p < 0.0001). Our results show that Achilles symptoms could also be associated with an increase in the paratenon thickness. We suggest that clinicians should carefully analyze paratenon thickness when evaluating patients with Achillodynia using ultrasound. It may be that the paratenon, when thickened, may explain some of the painful symptoms reported by patients and it is associated with a tendinopathy process, hence we suggest careful analysis in patients with Achillodynia.

Natale et. al.'s response to Stecco's fascial nomenclature editorial.

Despite their importance in anatomy, physiology, pathology and surgery, the fasciae and the fascial spaces have been poorly described in classic textbooks. This little attention depends on the fact that these fasciae vary in thickness and composition, especially at the cervical level. Indeed, in the main literature they have been described in different forms. Furthermore, the definition itself of the fascia is not consistent in a variety of authors. As a consequence, different criteria have been used to define and classify the fascial systems. In this paper, a brief terminological history and the most common nomenclatures and classifications of the fascia have been summarized.

High-intensity exercise training induces morphological and biochemical changes in skeletal muscles.

IN THE PRESENT STUDY WE INVESTIGATED THE EFFECT OF TWO DIFFERENT EXERCISE PROTOCOLS ON FIBRE COMPOSITION AND METABOLISM OF TWO SPECIFIC MUSCLES OF MICE: the quadriceps and the gastrocnemius. Mice were run daily on a motorized treadmill, at a velocity corresponding to 60% or 90% of the maximal running velocity. Blood lactate and body weight were measured during exercise training. We found that at the end of training the body weight significantly increased in high-intensity exercise mice compared to the control group (P=0.0268), whereas it decreased in low-intensity exercise mice compared to controls (P=0.30). In contrast, the food intake was greater in both trained mice compared to controls (P < 0.0001 and P < 0.0001 for low-intensity and high-intensity exercise mice, respectively). These effects were accompanied by a progressive reduction in blood lactate levels at the end of training in both the exercised mice compared with controls (P=0.03 and P < 0.0001 for low-intensity and high-intensity exercise mice, respectively); in particular, blood lactate levels after high-intensity exercise were significantly lower than those measured in low-intensity exercise mice (P=0.0044). Immunoblotting analysis demonstrated that high-intensity exercise training produced a significant increase in the expression of mitochondrial enzymes contained within gastrocnemius and quadriceps muscles. These changes were associated with an increase in the amount of slow fibres in both these muscles of high-intensity exercise mice, as revealed by the counts of slow fibres stained with specific antibodies (P < 0.0001 for the gastrocnemius; P=0.0002 for the quadriceps). Our results demonstrate that high-intensity exercise, in addition to metabolic changes consisting of a decrease in blood lactate and body weight, induces an increase in the mitochondrial enzymes and slow fibres in different skeletal muscles of mice, which indicates an exercise-induced increase in the aerobic metabolism.

Amphetamines induce ubiquitin-positive inclusions within striatal cells.

The present study explores whether effects induced by amphetamine derivatives on striatal GABA cells might be connected with effects on dopamine (DA) metabolism. Methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") were administered to C57Black mice following a dosage regimen in which various doses of both drugs were injected i.p. at 2-h intervals. Neuronal inclusions produced under these experimental conditions were examined under electron microscopy. Drugs reducing DA availability prevented inclusion formation; conversely we observed that increasing DA synthesis or impairing physiological DA degradation enhanced the number of inclusions. The present study indicates that the presence of extracellular striatal DA is essential for the production of subcellular alterations induced by amphetamine derivatives. This is in line with a recent hypothesis connecting striatal DA release with degeneration of striatal GABA neurons.

Comparative analysis of senescent exorbital lacrimal glands in male and female albino rats.

In our previous study we described a bilateral-macroscopic and structural dimorphism of young rat exorbital lacrimal gland (Loewenthal's gland), which was the probable cause of the bibliographic discrepancies in the entity and the onset of its sexual dimorphism. Relevant literature also reported sex-dependent alterations in gland structure during senescence. The present study aims to carry out a comparative analysis on age-dependent changes in glands of both sides from male and female rats, using histological, histochemical and transmission electron microscopy, to evaluate whether the gland bilateral-macroscopic and structural dimorphism might influence the kind of alterations which occur in senescence. Our findings indicate that the macroscopic and structural side-specific dimorphism is not so evident in comparison with young rats. The side-specific dimorphism is evident only in male rats, in which the roundish gland appears to be more Sudan-positive in comparison with the ellipsoidal gland. The gland bilateral-macroscopic and structural dimorphism, although more evident in comparison with young animals, does not seem to influence these kinds of alterations due to senescence, a time-window in which we still observed some sexual differences also in more aged rats.

Morphological and biochemical evidence that apomorphine rescues striatal dopamine terminals and prevents methamphetamine toxicity.

Apomorphine, given by a single injection, repeated injections, or by continuous infusion, was tested for neuroprotective effects in mice administered methamphetamine or N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in order to induce striatal dopamine (DA) depletion. In the first part of the study, the DA agonist (R)-apomorphine was administered at various doses (1, 5, and 10 mg/kg), 15 min before methamphetamine (5 mg/kg x 3, 2 h apart). Mice were sacrificed 5 days later. In the second part, apomorphine was administered either continuously by subcutaneous minipump (cumulative daily dose of 0.5, 1, and 3.15 mg/kg), or as single, repeated daily injections (up to 5 mg/kg) starting 40 h after an acute administration of MPTP (30 mg/kg). Mice were sacrificed at different time intervals (up to 1 month) following MPTP injection. In all the animals, the integrity of striatal DA terminals was evaluated by measuring striatal DA levels and TH immunohistochemistry. Apomorphine dose-dependently prevented methamphetamine toxicity. These effects were neither due to a decrease in the amount of striatal methamphetamine nor to the hypothermia, and they were not reversed by the DA antagonist haloperidol. Moreover, chronic, continuous (but not pulsatile) administration of apomorphine rescued damaged striatal dopaminergic terminals. These findings confirm a protective effect of apomorphine that also consists of a neurorescue of damaged striatal DA terminals. This suggests a new hypothesis about the long-term benefits observed during continuous apomorphine administration in Parkinson's disease patients.

Noradrenergic loss enhances MDMA toxicity and induces ubiquitin-positive striatal whorls.

Movement disorders involve a number of neurodegenerative conditions, mostly affecting basal ganglia. Parkinson's disease (PD) is classically defined by the selective loss of dopaminergic neurons in the substantia nigra pars compacta. Administration of specific neurotoxins represents a common tool to reproduce this lesion. Among these, amphetamine derivatives act as powerful monoamine neurotoxins, impairing striatal dopamine (DA) axons in mice. Despite the well-investigated effects on striatal DA terminals, only sporadic studies have focused on the potential toxicity of amphetamines towards post-synaptic neurons within the striatum. In the present work we found that 3,4-methylenedioxymethamphetamine (MDMA) produces ultrastructural alterations in striatal cells, featuring as membraneous whorls, positive for ubiquitin and heat shock protein 70. These morphological alterations were enhanced in locus coeruleus-lesioned mice.

Ultrastructural localization of the NADPH-diaphorase activity in the Leydig cells of aging mice.

Recently, it has been shown that nitric oxide may inhibit the Leydig cell steroidogenesis. The present paper describes, by means of NADPH-diaphorase histochemistry, the ultrastructural localization of the enzyme nitric oxide synthase in the Leydig cells of young adult and aging mice. In the young adult mice, the enzymatic reaction was mainly located in the mitochondria and in some clustered cisternae of the smooth endoplasmic reticulum. The nuclear envelope was faintly labeled. In the aging mice, most Leydig cells showed an enhanced enzymatic reaction. Labeled mitochondria were increased in number, and labeled areas of the smooth endoplasmic reticulum were more numerous and extended. In addition, a strong enzymatic reaction was recognized in the nuclear envelope. We conjecture that the impaired steroidogenesis observed in the testis of aging mammals might, at least in part, depend on the increased nitric oxide production in the Leydig cells.

Time-dependent changes in adrenal cortex ultrastructure and corticosterone levels after noise exposure in male rats.

In response to a stressful stimulus, there is a marked activation of the hypothalamic-pituitary-adrenal axis leading to a release of adrenocorticotropic hormone. This, in turn, acts on the zona fasciculata of the adrenal cortex to increase corticosterone plasma levels. Given the frequency of chronic intermittent noise exposure in man, we selected loud noise to evaluate concomitant changes in the ultrastructure of the adrenal cortex and corticosterone release. Following chronic (21 days, 6 h per day) loud white noise exposure (100 dBA, 0-26 KHz), we found the zona fasciculata to be most sensitive to time-dependent ultrastructural changes. These consisted of modifications in cell compartments involved in hormone synthesis and release. On the other hand, we found a progressive increase in corticosterone plasma levels which reached a plateau 9 days after noise exposure. The significance of these changes, in relation to phenomena like sensitization to repetitive stress, are discussed. Furthermore, the present data suggest that chronic loud noise exposure might potentially lead to endocrine dysfunctions.

Ultracytochemical localization of the NADPH-d activity in the human nasal respiratory mucosa in vasomotor rhinitis.

OBJECTIVES: Description of the ultrastructural localization of nitric oxide synthase in the blood vessels of the nasal respiratory mucosa in patients with vasomotor rhinitis. STUDY DESIGN: This research was conducted on seven patients--men and women, ages 20 to 45 years--suffering from vasomotor rhinitis and who had undergone surgical therapy for reduction of the inferior turbinates. METHODS: To study the ultrastructural localization of nitric oxide synthase, NADPH-diaphorase cytochemistry was employed. Samples of the nasal mucosa were obtained from inferior turbinates. RESULTS: The endothelial cells of the arterioles, capillaries, venules and cavernous sinuses revealed a distribution of the enzymatic activity similar to that found in unaffected subjects. A strong enzymatic activity was recognized in the smooth muscle cells of the cavernous sinuses. The smooth muscle cells of arterioles and venules were generally found to be negative to enzymatic reaction. CONCLUSIONS: This study suggests that the vascular disorders of the vasomotor rhinitis depend, at least in part, from nitric oxide synthase induction in the smooth muscle cells of the cavernous sinuses.

The role of the locus coeruleus in the development of Parkinson's disease.

In Parkinson's disease, together with the classic loss of dopamine neurons of the substantia nigra pars compacta, neuropathological studies and biochemical findings documented the occurrence of a concomitant significant cell death in the locus coeruleus. This review analyzes the latest data obtained from experimental parkinsonism indicating that, the loss of norepinephrine in Parkinson's disease might worsen the dopamine nigrostriatal damage. Within this latter context, basic research provided a new provocative hypothesis on the significance of locus coeruleus in conditioning the natural history of Parkinson's disease. In particular, the loss of a trophic influence of these neurons might be crucial in increasing the sensitivity of nigrostriatal dopamine axons to various neurotoxic insults. In line with this, recently, it has been shown that locus coeruleus activity plays a pivotal role in the expression of various immediate early genes and in inducing the phosphorilation of cyclic adenosine monophosphate response element-binding proteins, suggesting a role of the nucleus in sustaining a protective effect.

Ultrastructural localization of calcium deposits in rat myocardium after loud noise exposure.

In previous studies we demonstrated that loud noise exposure induces ultrastructural alterations in the rat myocardium together with an increase in noradrenergic activity and in mitochondrial calcium influx. To verify the causal relationship between myocardial calcium entry and ultrastructural alterations induced by loud noise, in the present study we coupled routine electron microscopy with cytochemistry specifically dedicated to visualize calcium accumulation (revealed as antimonate deposits). We observed that the ultrastructural alterations occurring in both atrium and ventricle after 12 h of noise exposure, were densely packed with antimonate deposits. In particular, enlargements of the sarcoplasmic reticulum and dilution of the mitochondrial matrix, observed during routine electron microscopy, were markedly positive for calcium accumulation when observed by using antimonate. The present data strongly suggest that calcium entry results in accumulation of this ion at myocardial subcellular level. Moreover, the present results joined with previous evidence indicate that calcium accumulation is the final common pathway responsible for noise-induced myocardial morphological alterations.

Bilateral dimorphism of Loewenthal's gland in young male albino rats: an ultrastructural investigation.

This study represents a further contribution to our knowledge about the structure of Loewenthal's gland. There are several divergences in the available literature on the topic, concerning both the histological and ultrastructural findings. However, in these studies, the authors did not take into account the potential influence of a putative side-dependent dimorphism previously reported by us. We therefore carried out histological and electronmicroscopic observations specifically aimed at evaluating the importance of the gland shape for its structure. In particular, in male albino rats aged 70-120 days, we compared the structure of the left and right glands. Depending on the side undergoing morphological investigation, we observed differences in the acini, cells, nuclei, endoplasmic reticulum, Golgi apparatus and granular content. Apart from slight individual differences, we found that structural variations were most frequently observed in glands displaying a more evident macroscopic side-specific dimorphism. Our findings demonstrate that several conflicting data in the literature dealing with the structure of Loewenthal's glands might be explained by the morphofunctional side-dependent dimorphism of the organ.

Central and peripheral benzodiazepine ligands prevent mitochondrial damage induced by noise exposure in the rat myocardium: an ultrastructural study.

Noise represents an environmental stress factor affecting several organs and apparatuses, including the cardiovascular system. In experimental animals undergoing noise exposure, subcellular myocardial changes have been reported, especially at the mitochondrial level. In previous studies we found that diazepam, acting at both central and peripheral benzodiazepine receptors, prevented the onset of this myocardial damage. In the present study, we investigated the specific role played by central and/or peripheral benzodiazepine receptors in preventing noise-induced myocardial alterations. In particular, the effect of clonazepam as a selective ligand for central sites, in comparison with the efficacy of ligands selective for peripheral sites, such as Ro 5-4864 and PK-11195, was evaluated. Rats were pretreated with the test drugs 30 min before exposure to noise for 6 or 12 hr and then sacrificed. After fixing, samples of right atrium and ventricle were taken and processed for either transmission or scanning electron microscopy. After 6 hr of noise exposure, only the atrium exhibited significant mitochondrial alterations, whereas after 12 hr both atrium and ventricle were damaged. As expected, diazepam prevented noise-induced mitochondrial injury at both 6 and 12 hr. By contrast, clonazepam was effective only after 6 hr. The peripheral ligand PK-11195 attenuated mitochondrial damage at both 6 and 12 hr, whereas Ro 5-4864 was effective only after 12 hr. In the present study, we confirm that noise exposure induces mitochondrial damage in the rat myocardium. Drugs acting at both central and peripheral benzodiazepine receptors significantly prevent this damage. Differences in the amount and in the duration of the protective effect might depend on variability in the potency and in the pharmacokinetics of the specific drugs.

Ultrastructural localization of NADPH-diaphorase activity in the endothelial cells of human nasal respiratory mucosa.

The cavernous sinuses are the most peculiar feature of the nasal angioarchitecture, due to their ability to retain a large quantity of blood in reply to a variety of topical and systemic stimuli. Recently, nitric oxide (NO) has seemed to be crucially involved in the nasal vascular regulation. The distribution of NO-synthase (NOS), the enzyme that catalyzes the formation of NO, was studied in the endothelium of nasal blood vessels by the ultracytochemical detection of reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) enzymic activity. The endothelium of the cavernous sinuses appeared strongly positive, whereas the endothelium of arterioles was occasionally labeled. The endothelial cells of capillaries and venules were found to be NADPH-d negative. The strong enzymic activity observed in the cavernous sinuses suggests a major role of NO in the capacitance vessels compared to the resistance vessels. The hypothesis of a reciprocal inhibition between the NOS enzymic pathways present in the respiratory epithelium and in the endothelium of cavernous sinuses is put forward. The nasal disorders characterized by anomalous vasomotility and vascular permeability could be caused in part by the irregular control of these complex interactions.

Long-term exposure to noise modifies rat adrenal cortex ultrastructure and corticosterone plasma levels.

Female rats were exposed to noise 6 h daily for 7 or 21 days running. The effects of stress were evaluated both on adrenal cortex ultrastructure and on plasma corticosterone levels. Subcellular examination showed a marked involvement of each zona of the adrenal cortex. In particular, we observed various alterations, the most frequent consisting of diluted matrix and cristolysis of mitochondria and swelling of smooth endoplasmic reticulum membranes. These morphological changes were most prominent after longer exposure to noise. Similarly, corticosterone plasma levels significantly increased over the time of application of noise stimulus. The present findings indicate that prolonged exposure to loud noise induced structural and functional modifications in the adrenal gland. These data might be potentially relevant in contributing to explain the effects induced in humans exposed to loud noise in a variety of environmental conditions.

Ultrastructural and biochemical evidence of apoptosis induced by a novel inhibitor of protein geranylgeranylation in human MIA PaCa-2 pancreatic cancer cells.

Analogs of geranylgeranyl diphosphate (GGdP) have been demonstrated to inhibit the geranylgeranylation of proteins, producing cytotoxic activity in human prostate cancer cells. A detailed study is reported on the programmed cell death in vitro of human exocrine pancreas cancer cells (MIA PaCa-2) induced by the most active compound of this series of geranylgeranylation inhibitors, the dipotassium salt of (E,E,E)[2-oxo-2-[[(3,7,11,15-tetramethyl-2, 6,10,14-hexadecatetraenyl)-oxy]amino]ethyl] phosphonic acid (BAL 9504), using transmission and scanning electron microscopy (SEM). The results show that, after 72 h of treatment with BAL 9504, 25 microM, most MIA PaCa-2 cells display the typical morphological features of apoptosis, including condensation of nuclear chromatin, dilation of endoplasmic reticulum, and fragmentation of both nucleus and cytoplasm, giving rise to small membrane-bound vesicles (apoptotic bodies); surface protrusions and blebs are well demonstrated by SEM. The electrophoresis showed the presence of various bands corresponding to fragmented DNA of 180 base pairs, or multiples of this length, thus indicating that BAL 9504 effectively induces apoptosis. The present study provides the first evidence that inhibition of protein geranylgeranylation produces apoptosis in human MIA PaCa-2 exocrine pancreas cancer cells.

Diazepam reduces ultrastructural changes induced by noise stress in rat adrenal gland.

Male rats were exposed to noise for 6 running hours and the effects of pretreatment with the benzodiazepine diazepam on the adrenal gland were evaluated. Ultrastructural examination showed that, after noise exposure, zona reticularis cells resulted the more affected, exhibiting areas of diluted cytoplasm, disarranged endoplasmic reticulum, membrane vestigia and some altered mitochondria; diluted cytoplasmic areas appeared in noradrenaline-storing cells, too. On the contrary, zona reticularis cells from diazepam-pretreated and noise-exposed rats resulted significantly less altered, as well as the noradrenaline-storing cells. The present findings indicate that diazepam is able to exert some protective action on adrenal gland alterations due to noise exposure.

Identification of critical residues of staphylococcal enterotoxin B for lymphomonocyte proliferation and cytokine production.

Superantigens bind to major histocompatibility complex class II molecules and stimulate large numbers of T cells expressing particular Vbeta elements of the T-cell receptor. Staphylococcal enterotoxin B (SEB) is a bacterial superantigen that causes food poisoning and toxic-shock syndrome. The toxicity of SEB is thought to be mediated by T-cell stimulation and cytokine production. Different regions of the SEB molecule are important for mitogenic activity. To identify critical residues of SEB in the region 124-1 54, which competitively inhibits the mitogenic activity of the toxin, we used the synthetic peptide approach and alanine scanning mutagenesis as a probe. We synthesized eight peptides with alanine replacement of all residues in the SEB sequence 131-138 and tested them for the capacity to inhibit both SEB-induced proliferation of human lymphomonocytes and the production of tumor necrosis factor alpha and interferon gamma. Mutation to alanine of the residue Thr 133 improved the inhibition of SEB-induced proliferation and cytokine production, whereas the substitution of Ser 131 also increased the inhibition, albeit to a lesser degree. The peptide obtained by substitution of Val 136 with alanine was unable to inhibit SEB-induced proliferation and cytokine production, suggesting that Val 136 is essential for mitogenic activity. Thus hydrophobic interactions apparently are very important for mitogenic activity. The identification of critical residues in this active site in the SEB and the computer modeling based on crystal X-ray data contribute to a better understanding of the molecular mechanism of the superantigen and may be useful for therapeutical applications.