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Native stingless bee propolis (or cerume) has begun to be studied in the last decades, mainly focused on its pharmacological properties. In this study, however, the chemical composition of diverse samples of Tetragonisca angustulapropolis was compared via ESI-MS fingerprinting and ultra-high performance chromatography- mass spectrometry with extracts of Schinus terebinthifoliusRaddi (Anacardiaceae), a possible source of resins. These results confirmed that the samples of T. angustulapropolis, independently of their geographic origin, presented a similar composition to the flowers of S. terebinthifolius.The evaluation of their biological activity (antioxidant, antimicrobial and cytotoxic) showed that the plant extract was more active than the T. angustulapropolis samples, in spite of their similar composition, possibly due to quantitative variations in the composition due to freshness.

Digestibility of pollen grains of poppy (Papaver rhoeas) and hazelnut (Corylus avellana) subjected to a human-like in vitro digestion with pancreatic enzymes was evaluated. Pollens showed different types of walls. Digestibility was determined for total protein and insoluble carbohydrate contents by means of a new application of microspectrophotometry. Results demonstrated that pollen grains of both species were only partly digested; after 24h treatment, only 26% of carbohydrates and 48% of proteins were digested in poppy and only 3% and 59% in hazelnut. This is probably due to the difficulty of enzymes to penetrate the intine of pollen grains. The degree of digestion of insoluble carbohydrates varied in the studied species according to their chemical nature and their storage sites.

Background:The few epidemiological data available in literature on neuroendocrine tumors (NET) are mainly based on Registry databases, missing therefore details on their clinical and natural history. Aim:To investigate epidemiology, clinical presentation, and natural history of NET. Design and setting:A large national retrospective survey was conducted in 13 Italian referral centers. Among 1203 NET, 820 originating in the thorax (T-NET), in the gastro-entero-pancreatic tract (GEP-NET) or metastatic NET of unknown primary origin (U-NET) were enrolled in the study. Results:93% had a sporadic and 7% a multiple endocrine neoplasia type 1 (MEN1)-associated tumor; 63% were GEP-NET, 33% T-NET, 4% U-NET. Pancreas and lung were the commonest primary sites. Poorly differentiated carcinomas were <10%, all sporadic. The incidence of NET had a linear increase from 1990 to 2007 in all the centers. The mean age at diagnosis was 60.0±16.4 yr, significantly anticipated in MEN1 patients (47.7±16.5 yr). Association with cigarette smoking and other non-NET cancer were more prevalent than in the general Italian population. The first symptoms of the disease were related to tumor burden in 46%, endocrine syndrome in 23%, while the diagnosis was fortuity in 29%. Insulin (37%) and serotonin (35%) were the most common hormonal hyper-secretions. An advanced tumor stage was found in 42%, more frequently in the gut and thymus. No differences in the overall survival was observed between T-NET and GEP-NET and between sporadic and MEN1 -associated tumors at 10 yr from diagnosis, while survival probability was dramatically reduced in U-NET. Conclusions:The data obtained from this study furnish relevant information on epidemiology, natural history, and clinico-pathological features of NET, not available from the few published Register studies.

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Abstract.:  The problem of the water content of pollen is reconsidered, especially the distinction between “partially hydrated pollen” (PH pollen), pollen with a water content greater than 30%, and “partially dehydrated pollen” (PD pollen), which has a water content of less than 30%. Both types have been found even in systematically contiguous groups or the same genus. Partially hydrated pollen, encountered in at least 40 families of angiosperms, has the advantage of germinating quickly, normally in a few minutes to less than an hour. Dispersal of highly hydrated pollen also occurs in orchids but for a different reason, i.e. to enable packaging of massulae. The disadvantage of pollen dispersed with a high water content is that water is readily lost and the pollen may desiccate and die unless it has biochemical or anatomical devices to retain water or phenological strategies, such as flowering when temperatures are not too high and when relative humidity is high. Most pollen of Gymnosperms and Angiosperms studied has, however, been found partially dehydrated.

Excessive laxity of the tarso-ligamentous sling of the lower eyelid may be caused by inadequate muscular support (resulting from injury to the muscle, facial palsy or senile degeneration) or prolonged mechanical distension (exophthalmia). Numerous techniques have been devised for functional reconstruction of the distended lower eyelid, based upon the principle that restoring the lower eyelid to its anatomical position will improve lacrimal transit and re-establish its natural protective function. We now use an autologous conchal cartilage graft to treat the distended or atonic lower eyelid. We review our results in a retrospective study of 20 patients, and aim to identify the indications for this procedure and to evaluate its advantages and disadvantages relative to other existing methods. All of our patients reported functional improvement after the operation in terms of decreased dry-eye symptoms, less epiphora and a decline in keratitis and conjunctivitis. All patients also reported a visible cosmetic improvement postoperatively. The major drawback of this operation is the partial loss of the visual field when looking down, due to the limited lowering of the lower eyelid. The stability of our results compares favourably with that achieved using other currently available techniques. We conclude that autologous conchal cartilage grafting is an effective procedure for improving both the function and the appearance of the atonic lower eyelid.

Melanotic neuroectodermal tumour (MNET) of infancy is a rare benign but locally aggressive tumour. We describe our surgical treatment of MNET of the orbital region. There was osteogenic relapse involving the bone of the orbit, 20 days after macroscopically complete excision of the primary tumour when the patient was 12 weeks old. This is only the second report of osteogenic relapse in MNET. The relapse was treated by excision of the involved orbital floor, preserving the orbital periosteum. The tumour has not recurred in 23 months of follow-up. Residual tumour islets may regress spontaneously after incomplete excision of MNET, but the relapse rate is between 15% and 45%. In our opinion, excising a safety margin of a few mm of apparently healthy bone reduces the risk of relapse. In contrast, the orbital contents should be preserved if they are macroscopically normal. Follow-up consisted of frequent physical examinations and CT scans.

Summary: The aim of this paper is to draw attention to partially hydrated pollen, namely, pollen grains having a high water content (>30%); this type of pollen is more frequent than previously thought. Various cyto-physiological strategies are used to retain water during exposure and dispersal such as cytoplasm carbohydrates; in the absence of such strategies, fast pollination must be ensured, because uncontrolled loss of water leads to pollen death. On the other hand, a state of partial hydration allows a fast tube emission (even within 3–5 min). Several methods for determining the hydration status of pollen at anthesis are proposed.

The problems involved in applying histochemical and cytochemical methods to mature angiosperm pollen for bright light and fluorescence microscopy are discussed. These methods can be used for general examination or to reveal particular structures or groups of substances. The main methods of testing pollen viability and germinability based on stains and semiquantitative methods are also reviewed. The main methods of staining and their applications are summarised.

An outbreak of hepatitis A started in late October 1996 in a nursery school in Tuscany, Italy. A programme of hepatitis A vaccination without the use of immunoglobulin started at the beginning of December 1996 and included 33 children, 21 household contacts and 6 adults working in the school. Overall, 11 cases occurred in children attending the school (attack rate 27%) and 10 among their household contacts (attack rate 9%). The latter also included parents, and, in two cases, grandmothers. The data indicate that susceptibility to HAV has increased over recent decades in central Italy. Past and recent experience shows that the usual duration of hepatitis A epidemics in the absence of immune prophylaxis is longer than that described here. The use of hepatitis A vaccine probably contributed to the early extinction of the outbreak, because no further cases were notified in the area after 7 February 1997.

Abstract:  This study aimed to determine the presence of neurons responding to visual stimuli in area F2 of the dorsal premotor cortex of the macaque monkey. In order to delimit the sector in which visually responsive neurons are located, the somatotopic organization of area F2 was studied with intracortical microstimulation and single neuron recording. The results showed that: (1) in area F2 there is a significant percentage of visually responsive neurons (15.9% of all recorded neurons); (2) area F2 is excitable with a low-threshold current (average 28.1 A) and has a somatotopic representation of the whole body, except the face; and (3) most visually driven neurons (n=130 out of 169) are concentrated within the rostrolateral sector of the forelimb representation of area F2, thus providing for the first time functional support for the neuroanatomical evidence that the visual input to area F2 is mostly restricted to this sector.

Some aspects of pollen cytology at dispersal were studied in 12 species of gymnosperms. The pollen grains differed in: 1. volume and cell number; 2. polarization of external structure and internal cell components; 3. wall thickness, especially of the intine, and the resulting percentage of cell volume with respect to total pollen grain volume; 4. stratification and chemical nature of the various intine layers; 5. nature and location of polysaccharide reserves; 6. morphological differences between the dry and hydrated states and phenomena related to hydration; 7. presence and site of orbicles. The various characters are compared and discussed in relation to the length of the reproductive cycle and the relations between the male gametophyte and its female counterpart.

Gonadal steroids drive the significant bone mineral increase that occurs at puberty. Oestrogen deprivation in women results in bone loss. We investigated bone mineralization by single photon absorptiometry in girls with central precocious puberty (n=13, age 3.8–8.5 years) before and during 1 year of treatment with gonadotropin releasing hormone analogue (GnRH-a=longacting D-Trp6-GnRH, 60 μg i.m. every 28 days). Before GnRH-a therapy, bone mineral density (BMD) was significantly higher in patients than in ten control girls matched for chronological age (patients 0.575±0.097 g/cm2, controls 0.433±0.049 g/cm2,P<0.001). Patient BMD was not significantly different from that of ten control girls matched according to patient bone age (0.550±0.046 g/cm2,P=NS). During GnRH-a treatment, pituitary-gonadal axis was suppressed and patient BMD significantly decreased (6 months: −6.0%,P<0.002 vs baseline; 12 months: −8.0%,P<0.001 vs baseline). We conclade that in girls with precocious puberty the activation of gonadal steroid secretion induces an increase in bone mineralization and that oestrogen deprivation by GnRH-a treatment caused a significant decrease in BMD.

It appears that the tapetum is universally present in land plants, even though it is sometimes difficult to recognize, because it serves mostly as a tissue for meiocyte/spore nutrition. In addition to this main function, the tapetum has other functions, namely the production of the locular fluid, the production and release of callase, the conveying of P.A.S. positive material towards the loculus, the formation of exine precursors, viscin threads and orbicules (= Ubisch bodies), the production of sporophytic proteins and enzymes, and of pollenkitt/tryphine. Not all these functions are present in all land plants:Embryophyta. Two main tapetal types are usually distinguished in theSpermatophyta: the secretory or parietal type and the amoeboid or periplasmodial type; in lower groups, however, other types may be recognized, with greater or lesser differences. A hypothetical phylogenesis of the tapetum is proposed on the basis of its morphological appearance and of the nutritional relations with meiocytes/spores. The evolutionary trends of the tapeta tend towards a more and more intimate and increasingly greater contact with the spores/pollen grains. Three evolutionary trends can be recognized: 1) an intrusion of the tapetal cells between the spores, 2) a loss of tapetal cell walls, and 3) increasing nutrition through direct contact in narrow anthers.

Microstimulation of the rostral portion of the corpus callosum (CC) was carried out on 21 awake kittens ranging in age from 45 to 105 days to determine the age at which motor responses first appeared and that at which they assumed functional adult-like properties. Motor responses to microstimulation first appeared over an interval ranging from 78–86 days postnatally. As in adults, they consisted of discrete, well-localized contractions of shoulder, whisker, and eyelid muscles according to the stimulated sites. In the first days after their appearance, motor responses differed markedly from those in adults because: (a) they exhibited higher thresholds; (b) they did not faithfully follow pulse trains delivered at 10 s intervals; (c) they had variable and longer latencies. Thereafter, motor responses gradually became stable, faithfully followed suprathreshold stimulation delivered at 0.1/s frequency, and acquired lower thresholds and shorter latencies, until they exhibited adult-like properties at 93–100 days of age. Single-unit recordings were obtained from 138 fibres isolated in the same callosal region submitted to microstimulation in order to study the response properties of the callosal fibres to somatic stimuli in immature animals. On the basis of their reactivity to peripheral stimulation, fibres were classified into three main types: (1) unreactive units (58 fibres), which could not be driven by somatic stimuli. (2) Adult-like units (55 fibres), which were readily driven by somatic stimuli and were endowed with fixed and small receptive fields (RFs) indistinguishable from those of adults. (3) Immature units (25 fibres), which were unsteadily driven by somatic stimuli applied over large areas at the periphery. Neither the RFs nor the adequate stimuli could be reliably determined. This type of units was not found in the adult cat (Spidalieri et al. 1985). The proportion of unreactive units was the highest before the appearance of motor responses and gradually decreased, approaching the adult level after attaining adult-like motor responses. Conversely, the proportion of adult-like units was lowest before the appearance of motor responses and gradually increased, approaching the adult level after motor responses had acquired adult-like properties.

In fifteen awake, chronic cats single-unit recordings were obtained from 316 fibres isolated in the rostral portion of the corpus callosum (CC). Altogether, 304 units were reactive to peripheral stimuli. They were fired by hair bending, light touch or light pressure (S units; 79.3%) or by gentle rotation of joints and/or by pressure on muscle bellies or tendons (D units; 20.7%). All the reactive units were endowed with small and unilateral receptive fields (RFs) located in trigeminal (49.7%) or segmentai (50.3%) regions. Trigeminal and forepaw units had the smallest RFs. All the trigeminal units were of the S type. Their RFs were located in either the ophthalmic, maxillar, and mandibular face districts or in the oral vestible. The vast majority of segmental units (146 out 153 fibres) had RFs in the forelimb. Very few units were fired by stimulation of the trunk (6 fibres), and only one had its RF in the tail. Almost half of the forelimb units (69 fibres) were fired by stimulation of the most proximal parts of the forelimb and of the shoulder; about one third (57 fibres) exhibited RFs located in the forepaw; the remaining units (20 fibres) had their RFs in the intermediate region of the forelimb. Neither the trigeminal nor segmental RFs ever extended across the midline. The distribution of the fibres within the CC conformed to a somatotopic pattern. The representations of the trigeminal and segmental regions were largely coextensive. Along the rostro-caudal axis of the CC, units with RFs in the mandibular, maxillar and ophthalmic divisions of the trigeminal region tended to lie in this order in the rostralmost 4 mm. Segmental representation extended over the rostralmost 6 mm. Shoulder fibres were mainly found in the rostral half, whereas forepaw units were segregated in the caudal half.

The effects of microstimulation of the rostral portion of the corpus callosum (CC) were examined in seven chronic cats submitted to either unilateral motor cortex ablation (5 preparations) or transection of the rostral two thirds of the CC (2 preparations) in order to identify the routes (ortho-or antidromic) followed by callosal impulses to provoke the motor effects. As in intact animals, motor responses in lesioned preparations consisted of very localized contractions of shoulder, whisker, or eyelid muscles, according to the stimulated sites. Unlike intact animals in which motor responses upon CC microstimulation were bilateral and symmetrical (Spidalieri and Guandalini 1983), in lesioned preparations they appeared contralaterally to the emitting hemisphere, i.e., they were contralateral to the stimulated callosal stump (split-brain preparations) and ipsilateral to the side of the cortical lesion (preparations with unilateral motor cortex ablation), regardless of the current intensity applied (up to a maximum of 50 µA). The unilateral motor responses occurred by the first day after lesion and persisted for the duration of the experiments which lasted to a month or more. Since orthograde degeneration of callosal fibres deprived of their somata has been shown by previous anatomical studies to be complete within 11 days after lesion, these results indicate that selective antidromic activation of callosal fibres is capable of eliciting motor responses. Thresholds for the motor effects in lesioned preparations proved to be from 1.3 to 3.9 (mean, ¯x = 2.4±0.7 SD) times higher than those found before motor cortex ablation. By 18 days after lesion a decrease of threshold currents for the motor responses was observed ranging from 6 to 37% (mean, ¯x = 24.2±13.6 SD), depending on the stimulated sites, relative to values previously found. The shortest train duration and the lowest frequency for minimum threshold were longer (40 vs. 30 ms) and higher (400 vs. 300 Hz), respectively in lesioned preparations than in intact controls. Moreover, a decrease in train duration or frequency provoked larger threshold increases in lesioned preparations than those observed in intact animals. As a whole, these results suggest that in intact animals the motor effects are also mediated by orthodromic callosal volleys.

The effects of selective transection of the rostralmost portion of the corpus callosum, which contains fibres interconnecting the motor cortices of the two hemispheres, on frequency of occurrence and latency of conditioned responses (CRs) in both eyes were examined in seven cats trained to blink in response to a 500-ms tone. A 100-ms air-puff delivered to one eye only (ipsilateral eye) 400 ms after tone onset was used as an unconditioned stimulus. Both before and after callosal lesion, bilateral CRs were the most frequent response pattern. Following callosal lesion, a statistically significant reduction in the percentage of CRs in at least one eye was observed in only two cats. In all seven animals, both before and after callosal lesion, the mean CR latencies of the ipsilateral eye were significantly shorter than those of the contralateral eye. Callosal lesion caused a significant increase in the mean CR latencies of both eyes in all subjects. These results provide evidence that the two hemispheres influence each other in controlling conditioned bilateral blinking by reciprocally exchanging facilitatory signals contributing to initiation of CRs in both eyes.

Tachyphylaxis (TPX) to the spasmogenic activity of 5HT can be demonstrated in vivo in the superficial hand dorsal veins in man by the computerized venotest. The 5HT-TPX is reverted by previous local naloxone administration. Tachyphylaxis to 5HT is usually absent in the migraineur. The restored 5HT spasmogenic effect by naloxone suggests the possibility of local opioid apparatus participation in TPX to 5HT.

Summary Ultrastructural aspects of pore development inParietaria officinalis L. pollen are described. The main feature is the presence of intine wall projections formed in correspondence to the pores during the late microspore stage and persisting in the shedding pollen. This structure coexists with the tubules occurring in the pore and first appearing as evaginations of the plasma membrane.

NIR reflectance spectroscopy was applied to the identification of plant drugs. It was possible to satisfactorily distinguish ginseng, Silybwn marianum and grape seeds, directly analysing the product in its finished form. It was possible to identify Silybum samples grown in different areas. Ginseng samples containing starch were identified and old and young roots were distinguishable. Semiquantitative assay of ginsenoside content was possible.

Sections of Ammi visnaga (L.) Lam. ripe fruits were examined by U.V. microscopy under U.V. 365 nm light and under mixed U.V. 365 nm and visible light. The examination revealed a substance with blue autofluorescence inside the primary rib channels; a blue colour was shown also by the endosperm, whilst vittae were empty. In sections extracted with a selective method for the furanochromones khellin and visnagin, the substance filling primary rib channels was completely dissolved, and the colour of endosperm faded. The extract was analysed by high-performance liquid chromatography: the solubilized materials were composed almost exclusively of khellin and visnagin. These data are in contrast with the previous consensus which considered coumarins and coumarin-like compounds to be located in the vittae of Umbelliferae fruits, and never present in endosperms, whilst primary rib channels were thought empty in ripe fruits.