Yes, I will do it! Factors promoting the intention to volunteer after COVID-19 pandemic in Italy

This cross-sectional study assessed the extent to which the intention to volunteer after the COVID-19 pandemic is associated with resilience, post-traumatic growth, and community service self-efficacy in a representative Italian sample (N = 295; Mage  = 44.77; SD = 14.79; range = 18-83 years; 53.22% men). The model tested through a path analysis revealed a positive association between community service self-efficacy and intention to continue volunteering. Multi-group comparisons revealed that this relationship was maintained in participants who were active volunteers, while in the group of former volunteers, only a positive association between post-traumatic growth and intention to volunteer was found. This study contributed to highlight the importance of community service self-efficacy and post-traumatic growth in the volunteering experience and the intention to continue volunteering in the future.

Hypoglossal nucleus projections to the rat masseter muscle

We investigated in the rat whether hypoglossal innervation extended to facial muscles other than the extrinsic musculature of the mystacial pad. Results showed that hypoglossal neurons also innervate the masseter muscle. Dil injected into the XII nucleus showed hypoglossal axons in the ipsilateral main trunk of the trigeminal nerve. After Gasser's ganglion crossing, the axons entered into the infraorbital division of the trigeminal nerve and targeted the extrinsic muscles of the mystacial pad. They also spread into the masseter branch of the trigeminal nerve to target the polar portions of the masseter muscle spindles. Retrograde double labelling, performed by injecting Dil into the pad and True Blue into the ipsilateral masseter muscle, showed labelled hypoglossal neurons in the medio-dorsal portion of the XII nucleus. The majority of these neurons were small (15-20 microm diameter), showed fluorescence for Dil and projected to the mystacial pad. Other medium-size neurons (25 microm diameter) were instead labelled with True Blue and projected to the masseter muscle. Finally, in the same area, other small hypoglossal neurons showed double labelling and projected to both structures. Functional hypotheses on the role of these hypoglossal projections have been discussed.

Branching projections of catecholaminergic ventrolateral reticular neurons to the fastigial nucleus and superior colliculus in the rat: triple labelling procedure

In this study, we employed triple fluorescent-labelling to reveal the distribution of the catecholaminergic neurons within rostral ventrolateral reticular nucleus which supply branching collateral input to the superior colliculus (SC) and to the cerebellar fastigial nucleus (FN). The catecholaminergic identity of the neurons was revealed by immunocytochemical detection of the biosynthetic enzyme, tyrosine hydroxylase. The projections were defined by injections of two retrograde tracers: rhodamine and fluoro gold in the SC and FN, respectively.

Release properties and functional integration of noradrenergic-rich tissue grafted to the denervated spinal cord of the adult rat

Noradrenaline- (NA-) containing grafts of central (embryonic locus coeruleus, LC) or peripheral (juvenile adrenal medullary, AM, autologous superior cervical ganglionic, SCG) tissue were implanted unilaterally into rat lumbar spinal cord previously depleted of its NA content by 6-hydroxydopamine (6-OHDA) intraventricularly. A microdialysis probe was implanted in the spinal cord 3-4 months after transplantation, and extracellular levels of noradrenaline were monitored in freely moving animals during basal conditions and following administration of pharmacological or behavioural stimuli. Age-matched normal and lesioned animals both served as controls. Morphometric analyses were carried out on horizontal spinal sections processed for dopamine-beta-hydroxylase (DBH) immunocitochemistry, in order to assess lesion- or graft-induced changes in the density of spinal noradrenergic innervation, relative to the normal patterns. In lesioned animals, the entire spinal cord was virtually devoid of DBH-positive fibers, resulting in a dramatic 88% reduction in baseline NA, compared with that in controls, which did not change in response to the various stimuli. LC and SCG grafts reinstated approximately 80% and 50% of normal innervation density, respectively, but they differed strikingly in their release ability. Thus, LC grafts restored baseline NA levels up to 60% of those in controls, and responded with significantly increased NA release to KCl-induced depolarization, neuronal uptake blockade and handling. In contrast, very low NA levels and only poor and inconsistent responses to the various stimuli were observed in the SCG-grafted animals. In AM-grafted animals, spinal extracellular NA levels were restored up to 45% of those in controls, probably as a result of nonsynaptic, endocrine-like release, as grafted AM cells retained the chromaffine phenotype, showed no detectable fibre outgrowth and did not respond to any of the pharmacological or behavioural challenges. Thus, both a regulated, impulse-dependent, and a diffuse, paracrine-like, NA outflow may play roles in the recovery of lesion-induced sensory and/or motor impairments previously reported with these types of grafts following transplantation into the severed spinal cord.

Extensive and permanent motoneuron loss in the rat lumbar spinal cord following neurotoxic lesion at birth: morphological evidence

The efficacy of the neurotoxic lectin volkensin to induce motoneuron loss in the lumbar spinal cord was investigated at different time-points following unilateral injection into the medial gastrocnemius muscle of newborn (postnatal day 1 (PD 1)) animals, using retrograde fluorescent neuron labelling and histochemical procedures to evaluate the extent of the toxin-induced depletion, in comparison with the effects produced by neonatal crushing of the sciatic nerve. The results show that very low doses (2.0 ng) of volkensin intramuscularly can produce extensive (about 90%) and long-lasting (up to at least 8 months post-lesion) motoneuronal loss in the lumbar spinal cord, whose magnitude is higher than that observed following mechanical injury of the developing peripheral nerve (50-60%). Volkensin-induced motoneuronal depletion may therefore represent a useful model for experimental studies aimed at functional cell replacement in the immature spinal cord.

Noradrenergic neurotransmission in the ventral spinal cord: basic characteristics and effects of denervating lesions, as studied in the awake rat by microdialysis

Extracellular levels of noradrenaline (NA) were measured in the ventral horn of the lumbar spinal cord in awake unrestrained rats using in vivo microdialysis coupled to a highly sensitive radioenzymatic assay. In normal animals, baseline NA output averaged 13.4 +/- 2.2 fmol/30 microliters. KCl (100 mM) or desipramine (5 microM) added to the perfusion fluid increased NA levels 11.2-fold and 2.2-fold, respectively, whereas neuronal impulse blockade by tetrodotoxin (1 microM) added in the presence of desipramine stimulation produced a 88% reduction of extracellular NA levels. Noradrenergic denervation of the spinal cord by either electrolytic destruction of the noradrenaline-containing axon terminals or intraventricular 6-hydroxydopamine produced, 3-4 weeks later, dramatic 84 and 91% reductions in baseline NA release associated to a marked loss of immunoreactive noradrenergic fibers throughout the spinal cord or caudal to the site of electrolytic damage and almost completely abolished responses to pharmacological manipulations. The results support the view that spinal extracellular NA levels are neuronally derived, also suggesting that noradrenergic neurotransmission in the ventral spinal cord largely (by at least 85%) depends on the integrity of descending brainstem afferents. The microdialysis technique, thus, appears to be a useful tool for future studies on strategies aimed at promoting reinnervation and functional recovery in the deafferented spinal cord.

Branching serotonergic and non-serotonergic projections from caudal brainstem to the medial preoptic area and the lumbar spinal cord, in the rat

The distribution and the chemical identity of retrogradely single and double labeled neurons in the caudal raphe nuclei were analyzed in the rat following injection of two fluorescent tracers into the medial preoptic area and the ventral/intermediate grey of the lumbar spinal cord, and serotonin immunocytochemistry. The results suggest that (1) neurons in the caudal raphe nuclei exhibit highly collateralized axons, able to simultaneously innervate rostrally- and caudally-located targets; (2) a large proportion (40-50%) of the raphe-spinal projection does not contain serotonin, which by contrast is present in more than 70% of the neurons projecting to the medial preoptic area; (3) only a small fraction of the observed collateralized projection is serotonergic. Thus, multiple transmitter systems are likely to be involved in the diffuse ascending and descending influence arising from these nuclei.

Activation of metabotropic glutamate receptors protects cultured neurons against apoptosis induced by beta-amyloid peptide

Prolonged exposure of cultured cortical cells or cultured cerebellar granule cells to the residue 25-35 fragment of beta-amyloid peptide (beta AP), beta AP(25-35), induced neuronal apoptosis, as revealed by morphological analysis, fluorescent chromatin staining, and immunodetection of oligonucleosomes released from the nucleus into the cytoplasm. beta AP(25-35)-induced apoptosis was insensitive to ionotropic glutamate receptor antagonists but was substantially attenuated by the metabotropic glutamate receptor (mGluR) agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid. The neuroprotective action of (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid was antagonized by (RS)-alpha-methyl-4-carboxyphenylglycine and was mimicked by (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine (a selective agonist of mGluR2 and -3 subtypes) and by L-2-amino-4-phosphobutanoate and L-serine-O-phosphate (selective agonists of mGluR4, -6, and -7 subtypes). However, whereas all of these drugs behaved as neuroprotectants in cultured cortical cells, only L-2-amino-4-phosphobutanoate and L-serine-O-phosphate [and not (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine] reduced beta AP(25-35)-induced apoptosis in cultured cerebellar granule cells. The neuroprotective activity of mGluR agonists may be related to their ability to inhibit membrane Ca2+ conductance, because drugs that block voltage-sensitive Ca2+ channels, such as nimodipine or Co2+, could also attenuate beta AP(25-35)-induced apoptosis.

[Wash and non-wash system in the perioperative recovery of blood in prosthetic surgery: ultrastructural assessment of corpuscular blood components]

AIM

The authors aimed to perform an ultrastructural morphological analysis of blood recovered using wash and non-wash systems in patients undergoing full cement-free hip replacement in order to evaluate the integrity of the various blood corpuscle components.

EXPERIMENTAL PROTOCOL

An open prospective study in patients undergoing full cement-free hip replacement at the Orthopedics Division of S. Orsola-Malpighi Policlinico in Bologna. Materials of S. Orsola-Malpighi Policlinico in Bologna.

MATERIALS AND METHODS

Blood recovered postoperatively using a non-wash system was studied in 6 patients. In a further 3 patients perioperatively recovered blood was studied after washing using Cell Saver Haemolite 2 before reinfusion. Red globules, white globules and plaelets were isolated from blood collected using these two different recovery systems and analysed by SEM.

RESULTS

Study of the ultrastructural morphology of various corpusculated blood fractions.

DISCUSSION AND CONCLUSIONS

From the data in our possession it appears that the ultrastructural morphology of the various corpuscle components of blood in subjects undergoing postoperative recovery is better preserved using a non-wash system. There was no sign of "polluting" material in terms of adipose cells or free bone fragments in either group.

Neurons in raphe nuclei pontis and magnus have branching axons that project to medial preoptic area and cervical spinal cord. A fluorescent retrograde double labeling study in the rat

In this study, we utilized a double retrograde axonal tracing technique to investigate the possible existence of collateralized axonal projections from raphe nuclei 'pontis' and 'magnus' to both medial preoptic area (MPA) and cervical spinal cord (C1-C2). Following microinjections of fluorescent tracers Fast blue (FB) and Diamidino yellow (DY) within MPA and C1-C2, substantial numbers of FB and DY single-labeled neurons, as well as FB-DY double-labeled neurons have been found within raphe nuclei 'pontis' and 'magnus'.

Branching projections from subcoeruleus area neurons to medial preoptic area and cervical spinal cord revealed by double retrograde neuronal labeling

In this study we utilized a double retrograde axonal tracing technique to investigate the possible existence of collateralized axonal projections of subcoeruleus area neurons to both 'medial preoptic area (MPA) and cervical (C1-C3) spinal cord'. Following microinjections of fluorescent tracers (Fast blue (FB) and Diamidino yellow (DY) within MPA and C1-C3, substantial numbers of FB and DY single-labeled neurons as well as FB-DY double-labeled branched neurons have been found within subcoeruleus area.

Role of the ventromedial hypothalamus in the regulation of adenohypophyseal immunoreactive dynorphin in the rat

In this study, we have examined the role of the dorsomedial (DMH), ventromedial (VMH) and arcuate (ARH) nuclei of the hypothalamus in the control of hypothalamic and pituitary immunoreactive (ir) dynorphin (Dyn) A and ir-Dyn B in the rat, by evaluating the effect of discrete, bilateral radiofrequency lesions in these structures. Lesions limited to the VMH reduced the content of ir-Dyn in the anterior pituitary but not in the neurointermediate lobe or in the hypothalamus. Gel chromatographic analysis of anterior pituitary extracts confirmed that ir-Dyn is mainly associated with high molecular weight forms containing Dyn A and Dyn B in their sequence. Anterior pituitary extracts of VMH-lesioned rats displayed a clearly lower proportion of these forms. Destruction of the DMH affected only the hypothalamic content of ir-Dyn; ablation of the ARH did not cause any significant change. Our results suggest that ablation of the VMH may disrupt critical neuronal connections to the median eminence originating in this nucleus or crossing it and participating in control of the adenohypophyseal pool of ir-Dyn.

Branching axons from subcoeruleus area project to the nucleus raphe pontis and hypothalamic zona incerta, as studied with the double fluorescent retrograde tracing technique

In this study we utilized a double retrograde axonal tracing technique to investigate the possible existence of collateralized axonal projections of subcoeruleus area neurons to both raphe pontis nucleus and hypothalamic zona incerta. Following microinjections of fluorescent tracers (Fast blue (FB) and Diamidino yellow (DY] within raphe pontis and zone incerta, substantial numbers of double-labeled branched neurons have been found within the subcoeruleus area.

Effect of discrete brain lesions on hypothalamic and pituitary immunoreactive dynorphin

Radiofrequency lesions of the anterior hypothalamic area reduced immunoreactive dynorphin (ir-DYN) in the hypothalamus and in the neurointermediate lobe of the pituitary. Ablation of the medial preoptic area was not associated with any significant modification of ir-DYN in the tissue examined. Destruction of the medial basal hypothalamus in parallel lowered ir-DYN in the hypothalamus and in both pituitary lobes. Neonatal administration of monosodium glutamate had no significant effect on ir-DYN. These findings indicate that changes of ir-DYN in the hypothalamus and pituitary are associated with the destruction of anatomically and functionally distinct neural systems.

Immunoreactive dynorphin-like material in rat pituitary after ovariectomy

Ovariectomy caused a significant increase of immunoreactive dynorphin-like material (IR-DYAN) in the anterior pituitary lobe of intact as well as of medial basal hypothalamus-lesioned rats. No change of IR-DYAN was observed in the neurointermediate lobe of the gland or in the hypothalamus. Estradiol benzoate reversed the increase of anterior pituitary IR-DYAN induced by ovariectomy and caused a reduction in sham-ovariectomized rats.

[Projections to the supraoptic and paraventricular nuclei studied in the rat by means of retrograde fluorescent tracers (fast blue, nuclear yellow)]

Afferent projections into rat supraoptic nucleus (SO) and paraventricular nucleus (PVH) were studied with two fluorescent retrograde neuronal tracers: Nuclear Yellow (NY) and Fast Blue (FB). FB labeled cells were found into paraolfactory area (ACB), basolateral amygdaloid nucleus (ABL), lateral hypothalamus (LH), ventromedial nucleus (VMH) and dorsomedial hypothalamic)nucleus (DMH), tegmental nucleus of the pons (TPO). NY labeled cells were found into posterior hypothalamus (PH), dorsal raphe nucleus (DR) and tegmental nucleus of the pons (TPO). Few double-labeled neurons were found into TPO. The finding of double labeled neurons in the TPO is of particular interest. This latter nucleus is classically connected to the cerebellum trough the olivary nucleus and can serve as liaison for transmission of messages, e.g. vestibular, regarding spacial position variations. We can conclude affirming that quite a lot of informations of diverse nature converges on the SO and PVH nuclei that by efferent pathways may regulate hypothalamic neurosecretion, thus modifying the animal's behaviour response to different external stimuli.

Effects of hypothalamic lesions on the content of dynorphin immunoreactivity in pituitary

Radiofrequency lesion of medial basal hypothalamus (MBH) caused a approximately 50% depletion of immunoreactive dynorphin (ir-dyn) both in the anterior and neurointermediate lobe of the pituitary, whereas radiofrequency lesions of both supraoptic and paraventricular nuclei (SON, PVN) resulted in an approximately 30% reduction in neurointermediate lobe only. MBH cells and/or fibers contribute, therefore, to adenohypophysis pool of ir-dyn. Moreover, since the loss of ir-dyn in neurohypophysis ascertained after MBH lesion is significantly higher than that obtained with SON and PVN destruction, it may be assumed that MBH also participate to ir-dyn pool in neurohypophysis.

[Injections of peroxidase in the ventrobasal complex of the amygdala: afferent connections]

The relationships between the ventrobasal (VB) complex of the amygdala and the other encephalic zones have been investigated. Horseradish peroxidase injections were made into the amygdaloid VB complex in seven adult rats, processed according to the Nauta method (2). HRP labelled somata were observed ipsi- and contralaterally into the lateral habenulae (HL), superior collicoli (CS), reticular formations (RF), dorsal and medial raphe nuclei (DR and MR), only contralaterally into bulbar dorsal vagal nucleus (NDV) Fig. 1).

In vivo and in vitro interference of phosphatidylserine liposomes on prolactin secretion in the rat

The effect of sonicated suspensions of phosphatidylserine (PS), an acidic phospholipid, was investigated on prolactin secretion utilizing in vivo and in vitro approaches. Acute and chronic administration of PS reduced plasma prolactin levels during different phases of circadian rhythms. The phospholipid was able to inhibit the plasma prolactin surge, which occurs in cycling female rats on the afternoon of proestrus. The time course of PS on prolactin secretion was characterized by a short latency (15 min) and a long duration of action (6 h). In rats with hypothalamic deafferentation PS partially reduced the increase of circulating prolactin induced by pretreatment with alpha-methyltyrosine. An inhibition of prolactin release was observed if anterior pituitary glands were incubated in presence of PS. This effect was prevented by the addition of the dopamine antagonist sulpiride to the medium. In conclusion, PS decreases prolactin secretion both in vivo and in vitro. The inhibition of the hormone secretion appears to be due to the action of PS at the level of the pituitary; however, a concomitant stimulatory action on the turnover of the tuberoinfundibular neurons cannot be ruled out.

Morphological effects of cytidin-diphosphate-choline on rats with lesions of the substantia nigra: study using horse radish peroxidase method

Morphological effects of Cytidin-diphosphate-Choline (CDP-choline) (Ni-cholin) on rat brain with Substantia nigra lesions were studied by using the horse radish peroxidase method (HRP). Three groups of animals were studied. Post-lesion axonal and cellular regeneration was detected only in the group of rats treated with CDP-choline q.d. i.m. for 15 days.

[Afferent and efferent connections between the hypothalamus and raphe. Study using the technic of retrograde transport of peroxidases]

Projections between rat lateral hypothalamus and dorsal and medial raphe nuclei were studied. Horse radish peroxidase (HRP) was injected into each of these structures and retrogradely labeled neurons were identified. Following HRP injections into lateral hypothalamus (LH) labeled neurons were found into medial and cortical amygdaloid nuclei (AME, ACO), into dorsal thalamic nucleus (MD), in the hippocampal gyrus (HPC) and into medial raphe nucleus (MR). Following HRP injections into medial (MR) and dorsal (DR) raphe nuclei, labeled neurons were found in medial, lateral and posterior hypothalamus. A functional circuit was supposed between midbrain raphe and hypothalamus.

[Afferent connections in the ventromedial hypothalamus of rats demonstrated by retrograde transport of horseradish peroxidase]

Projections into rat ventromedial hypothalamus were studied with retrograde transport of horseradish peroxidase (HRP). Following injection of HRP into ventromedial hypothalamus, labeled neurons were found in cortical and medial amygdaloid nuclei, ipsilateral mediodorsalis thalamus (MD), dorsal raphe nucleus, and contralateral sensorimotor cortex. Futhermore, labeled axons that connect directly amygdala with hypothalamus (DAH) also were found.

[Behavioral effects of medial-dorsal thalamic, mediobasal hypothalamic and amygdaloid lesions in the rat]

Experiments were carried out to examine the effects of restricted brain lesions on activity, emotionality and aggressiveness of rats. The open-field activity test, the number of defecations test and the interspecific aggressiveness test were, respectively, employed. Lesions were placed on medial thalamus (MD), ventromedial (VM) or arcuate (ARH) hypothalamic nuclei, medial (AME) or intercalate (ICL) amygdaloid nuclei. No aggressiveness was detected in the rats under experiment, independently of the type of lesion. The open-field activity test given significant differences between control rats and animals with VM, ARH, AME or ICL lesion. Remarkable changes in the emotionality were found only between sham-operated controls and MD lesioned rats. It was concluded that hypothalamus and amygdala lesioned nuclei play a role in the neural mediation of activity, while medial thalamus influences the mediation of emotional response.

[Mitotic activity in the glandular epithelium of the rat small intestine after electrothermocoagulation of the tubero-infundibular region of the hypothalamus and simultaneous resection of the pineal gland]

Radio-frequency lesions of the tubero-infundibular region of the hypothalamus and simultaneous pinealectomy are performed in rats. The double operation is followed by a significant increase of mitotic rate in the small intestine glandular epithelium. This increase is higher than the addition of the effects that are caused by each operation.

[The effects of lesions in several zones of the brain on cell multiplication in the glandular epithelium of the rat small intestine]

Radio-frequency lesions of tubero-infundibular region of the hypothalamus are followed by a significant increase of the mitotic rate in the small intestine glandular epithelium in rats. This increase does not occur when radio-frequency lesions are located in the anterior and posterior hypothalamus, in the dorsomedial thalamus and in the cerebral hemispheres.