106 research outputs found
Morfo-anatomia dello sviluppo del seme in Coffea arabica L. cv. Mundo Novo
2007/2008Questo lavoro mirato allo studio dello sviluppo del seme di Coffea arabica, avvalendosi di differenti tecniche microscopiche, ha cercato di dare un contributo agli studi effettuati precedentemente da Houk (1938), Mendes (1941), Dedecca (1957), Wormer (1966), Dentan (1977, 1985) e De Castro (2002, 2005) che hanno apportato nozioni fondamentali a riguardo.
Il campionamento del materiale è stato effettuato da settembre 2006 a giugno 2007 su piante appartenenti al cv. Mundo Novo, all’Instituto Agronômico di Campinas (IAC, SP, Brasil). Sono stati raccolti quindi circa 60 campioni per ciascun stadio di sviluppo a scadenza bisettimanale dal momento della fioritura fino a completa maturazione del frutto, per un totale di 34 settimane after anthesis (AA). I campioni sono stati quindi subito fissati e spediti in laboratorio a Trieste (Italia).
Per prima cosa è stata effettuata l’analisi dimensionale delle drupe su un pool di campioni scelto casualmente tra quelli arrivati in laboratorio usando un calibro digitale lungo tre linee di misura: lunghezza, asse maggiore e asse minore in millimetri, sia per le drupe che per i semi. I campioni selezionati sono stati inclusi in resina Technovit 7100 (dall’inizio della fioritura fino alla 20a settimana AA) e tagliati con un microtomo rotativo (sezioni da 6 µm). I campioni dalla 22a settimana in poi sono stati tagliati invece con un criostato a bassa temperatura (da -15°C a -25°C; sezioni da 10-12 µm), a causa dell’aumento della durezza del materiale.
Sulle sezioni preparate sono state usate tecniche standard di osservazione in microscopia (ottica, SEM e TEM) e colorazioni istochimiche (ad es. Toluidin blue-O, Periodic Acid Schiff, DAPI etc.) ed è stata effettuata una messa a punto di protocolli specifici secondo la tipologia di tessuto osservata.
I risultati dell’analisi dimensionale hanno permesso di distinguere tre fasi di crescita dei frutti: 1. fase di quiescenza fino a 4 settimane dopo la fioritura (‘after anthesis’, AA); 2. fase centrale di sviluppo rapido (da 6 a 14 settimane AA); 3. fase di maturazione (da 16 settimane AA in poi).
La seconda fase è strettamente correlata alle condizioni climatiche del periodo, in particolare all’aumento della frequenza delle piogge.
Nella fase di crescita lenta l’ovario osservato in sezione longitudinale presenta la tipica struttura della drupa del caffè con due camere ovariche che ospitano un ovulo anatropo ciascuna. L’ovulo è composto da un funicolo, da un unico tegumento proveniente dal tessuto materno e da una zona di pochi micron occupata dal sacco embrionale non ancora sviluppato. E’ presente anche l’‘otturatore’ che, in Coffea, è di derivazione funicolare, formato da parenchima, conduce il tubetto pollinico al micropilo. Dopo circa un mese (4a -6a settimana) non si evidenzia ancora una crescita dimensionale del seme degna di nota.
Durante la fase centrale di sviluppo rapido il mesocarpo si accresce fino ad uno spessore di 0,6 mm.
A 8 settimane il seme ha 2 mm e il sacco embrionale fecondato ha iniziato il suo sviluppo con l’accrescimento dell’endosperma, inizialmente di tipo nucleare. A 10 settimane il seme ha 3 mm. Il sacco embrionale è più grande (0,2 mm) ed è formato da circa una ventina di cellule dell’endosperma. A 12 settimane il seme raggiunge i 10 mm. L’endosperma ha circa 1 mm. In questo stadio si nota un particolare strato tissutale che rappresenta la parte del perisperma che diventerà pellicola argentea. In seguito inizia ad intravedersi la pellicola argentea, con alcune cellule ancora vive e nucleate, e il pergamino si sta formando grazie a particolari modificazioni dell’endocarpo della drupa. Il seme ha quasi raggiunto la sua dimensione definitiva, alla 14a settimana.
Nella fase di maturazione la crescita dimensionale non è più così degna di nota, mentre si osservano cambiamenti chimici e strutturali. La 16a settimana è caratterizzata dalla quasi completa formazione della pellicola argentea, anche all’interno del solco. Molte cellule dell’endosperma sono in attività mitotica continua. Il pergamino invece è completamente formato a 18 settimane, caratterizzato da fibre fusiformi a pareti spesse. Dalla 20a settimana in poi, il tessuto dell’endosperma ormai formato ha ancora le cellule a pareti sottili (3 µm). In questa fase delicata il materiale ha caratteristiche intermedie, né duro né molle; il contenuto vacuolare delle cellule endospermiche si arricchisce di corpi proteici e strutture zuccherine, evidenziate con diverse colorazioni. L’embrione è formato e anche le sue cellule sono ricche di corpi proteici, evidenziati soprattutto con la colorazione UV-Schiff e l’osservazione in fluorescenza.
Le cellule dell’endosperma alla 26a settimana hanno un contenuto vacuolare ancora ricco di proteine e le pareti diventano più spesse (4-6 µm). Si osserva la formazione di alcune nodosità (Dentan, 1977) tipiche delle pareti cellulari dell’endosperma, soprattutto vicino alla cavità embrionale. Lo sviluppo del seme completo viene raggiunto alla 30a settimana, stadio in cui anche l’embrione sembra aver concluso la propria maturazione. Le pareti cellulari hanno raggiunto il loro spessore definitivo (da 6 a 10 µm). Infine, all’ultimo stadio (34 settimane AA), le cellule presentano un aspetto differente, risultano quasi più svuotate ed è difficile osservare i componenti cellulari con le colorazioni utilizzate fino ad ora. La maggior parte delle pareti presentano nodosità . Queste caratteristiche rappresentano uno stadio di sovra-maturazione della drupa.
Oltre agli aspetti puramente morfo-anatomici, l’abilità di sezionare i tessuti seminali potrebbe essere di grande importanza per eventuali analisi biomolecolari di espressione genica, come già è stato in parte studiato recentemente (De Castro & Marraccini, 2006). Conoscere infatti gli stadi di sviluppo e i tessuti coinvolti in ciascuna fase, dà la possibilità di evitare errori grossolani di interpretazione dei risultati e di stabilire relazioni interessanti fra la parte genetica e le osservazioni in microscopia.XXI Ciclo197
Azithromycin in COVID-19 Patients: Pharmacological Mechanism, Clinical Evidence and Prescribing Guidelines
The global COVID-19 pandemic has led to a race to find medications that can improve the prognosis of the disease. Azithromycin, in association with hydroxychloroquine or chloroquine, has been proposed as one such medication. The aim of this review is to describe the pharmacological mechanism, clinical evidence and prescribing guidelines concerning azithromycin in COVID-19 patients. There is weak evidence on the antiviral and immunomodulating effects of azithromycin, which in addition is not based on results from COVID-19 patients specifically. Therefore, this antibacterial should be considered only as empirical treatment of community-acquired pneumonia (CAP), although not all current treatment guidelines are in agreement. After the initial expectations raised by a small trial, more recent evidence has raised serious safety concerns on the use of hydroxychloroquine or chloroquine with azithromycin to treat COVID-19 patients, as all these drugs have arrhythmogenic potential. The World Health Organization has not made recommendations suggesting the use of azithromycin with hydroxychloroquine or chloroquine as treatment for COVID-19, but some national organisations have taken a different position, recommending this as first-line treatment. Several scientific societies, including the American College of Cardiology, have cautioned about the risks of this treatment in view of the lack of evidence concerning its benefits
Effect of PD98059, a selective MAPK3/MAPK1 inhibitor, on acute lung injury in mice.
The aim of the present study is to evaluate the contribution of mitogen-activated protein kinase 1–3 (MAPK3/MAPK1) in a model of acute lung inflammation in mice. Injection of carrageenan into the pleural cavity of mice elicited an acute inflammatory response characterized by: accumulation of fluid containing a large number of neutrophils (PMNs) in the pleural cavity, infiltration of PMNs in lung tissues and subsequent adhesion molecule expression (I-CAM and P-selectin), lipid peroxidation, and increased production of tumour necrosis factor-α, (TNF-α) and interleukin-1β (IL-1β). Furthermore, carrageenan induced lung apoptosis (Bax and Bcl-2 expression) as well as nitrotyrosine formation, NF-κB activation, and pJNK expression, as determined by immunohistochemical analysis of lung tissues and the degree of lung inflammation and tissue injury (histological score). Administration of PD98059, an inhibitor of MAPK3/MAPK1 (10 mg/kg) 1 h after carrageenan caused a reduction in all the parameters of inflammation measured. Thus, based on these findings we propose that inhibitors of the MAPK3/MAPK1 signaling pathways, such as PD98059, may be useful in the treatment of various inflammatory diseases
Aqueous extracts of walnut (Juglans regia L.) leaves: quantitative analyses of hydroxycinnamic and chlorogenic acids
Identification of both hydroxycinnamic and chlorogenic acids present in aqueous extracts of walnut leaves (Juglans regia L.) were carried out by using, for the first time, standard compounds not commercially available for qualitative identification. In particular, in addition to caffeic, ferulic, p-coumaric and sinapic acids, cis and trans mono-caffeoylquinic, dicaffeoylquinic, mono-feruloylquinic and cis and trans mono-p-coumaroylquinic acid isomers were detected and quantified by Ultra High Pressure Liquid Chromatography and the seasonal variations of these secondary metabolites were investigated
Distribution of p-coumaroylquinic acids in commercial Coffea spp. of different geographical origin and in other wild coffee species
Quantitative analyses of mono-p-coumaroylquinic acids (pCoQAs) and total chlorogenic acids (CGAs) in green
coffee commercial lots of C. arabica, C. canephora and C. liberica from different geographical origins and eight
wild Coffea species were carried out. Among the commercial lots, pCoQAs average content of C. arabica
(0.67 mg/g) is higher than that of C. canephora (0.40 mg/g) being C. liberica intermediate (0.58 mg/g). As far as
the analyzed wild Coffea species is concerned, C. pseudozanguebariae is characterized by the lower pCoQAs
content (0.12 mg/g) whereas C. sessiliflora is by far the richest source of pCoQAs (2.18 mg/g). Effect of the
roasting process on the mono-p-coumaroylquinic acids profile was evaluated for the economically exploited
species C. arabica and C. canephora. For the first time distribution of mono-p-coumaroylquinic acid isomers in
wild coffee species by fast and accurate UHPLC-DAD analyses using authentic standards previously synthetized,
is reported
Role of PPAR-δ in the development of zymosan-induced multiple organ failure: an experiment mice study
<p>Abstract</p> <p>Background</p> <p>Peroxisome proliferator-activated receptor (PPAR)-beta/delta is a nuclear receptor transcription factor that regulates gene expression in many important biological processes. It is expressed ubiquitously, especially white adipose tissue, heart, muscle, intestine, placenta and macrophages but many of its functions are unknown. Saturated and polyunsaturated fatty acids activate PPAR-beta/delta, but physiological ligands have not yet been identified. In the present study, we investigated the anti-inflammatory effects of PPAR-beta/delta activation, through the use of GW0742 (0,3 mg/kg 10% Dimethyl sulfoxide (DMSO) i.p), a synthetic high affinity ligand, on the development of zymosan-induced multiple organ failure (MOF).</p> <p>Methods</p> <p>Multiple organ failure (MOF) was induced in mice by administration of zymosan (given at 500 mg/kg, i.p. as a suspension in saline). The control groups were treated with vehicle (0.25 ml/mouse saline), while the pharmacological treatment was the administration of GW0742 (0,3 mg/kg 10% DMSO i.p. 1 h and 6 h after zymosan administration). MOF and systemic inflammation in mice was assessed 18 hours after administration of zymosan.</p> <p>Results</p> <p>Treatment with GW0742 caused a significant reduction of the peritoneal exudate formation and of the neutrophil infiltration caused by zymosan resulting in a reduction in myeloperoxidase activity. The PPAR-beta/delta agonist, GW0742, at the dose of 0,3 mg/kg in 10% DMSO, also attenuated the multiple organ dysfunction syndrome caused by zymosan. In pancreas, lung and gut, immunohistochemical analysis of some end points of the inflammatory response, such as inducible nitric oxide synthase (iNOS), nitrotyrosine, poly (ADP-ribose) (PAR), TNF- and IL-1as well as FasL, Bax, Bcl-2 and apoptosis, revealed positive staining in sections of tissue obtained from zymosan-injected mice. On the contrary, these parameters were markedly reduced in samples obtained from mice treated with GW0742</p> <p>Conclusions</p> <p>In this study, we have shown that GW0742 attenuates the degree of zymosan-induced non-septic shock in mice.</p
Real World Use of Antidiabetic Drugs in the Years 2011-2017: A Population-Based Study from Southern Italy
Diabetes mellitus is a metabolic disease characterized by chronic hyperglycemia. The availability of new antidiabetic drugs (ADs) has led to complex treatment patterns and to changes in the patterns of specific drug utilization. The aim of this population-based study was to describe the pattern of antidiabetic drugs (ADs) use in Southern Italy in the years 2011-2017, in relation to the updated type 2 diabetes mellitus (T2DM) therapy guidelines. A retrospective cohort study was conducted on T2DM patients using data from the Palermo Local Health Unit (LHU) claims database and diabetologist registry. The first-line treatment was investigated and incident treatments were identified and characterized at baseline in terms of demographics, complications, comorbidities, concomitant drugs and clinical parameters. Persistence to AD treatment was also evaluated. During the study period, one-third of first ever ADs users started the treatment with ADs other than metformin, in contrast to guideline recommendations. Among 151,711 incident AD treatments, the male to female ratio was 1.0 and the median age was 66 (57-75) years. More than half (55.0%) of incident treatments discontinued the therapy during the first year of treatment. In Italy, general practitioners (GPs) can only prescribe first-generation ADs, while the prescription of more recently marketed ADs, such as GLP-1RA, DPP4i and SGLT2i, is restricted to diabetologists only, based on a therapeutic plan. The role of GPs in the management of T2DM in Italy should be re-evaluated
Global incidence and prevalence of differentiated thyroid cancer in childhood: systematic review and meta-analysis
ObjectiveDifferentiated thyroid cancer (DTC) is rare in childhood and adolescence although it represents the most frequent endocrine malignancy in this population. DTC includes both papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC). Most pediatric DTCs are PTCs, while FTCs are rare. To date, no systematic reviews on the global epidemiology of pediatric and adolescent DTC have been published. This systematic review and meta-analysis aims to estimate the overall incidence and prevalence of DTCs in patients aged 0–19 years.MethodsThe systematic research was conducted from January 2000 to December 2021 through MEDLINE via PubMed, Cochrane Library, and Embase databases. Two separate meta-analyses were performed for PTC and FTC.ResultsAfter the selection phase, a total of 15 studies (3,332 screened) met the inclusion criteria and are reported in the present systematic review. Five studies were conducted in Europe, five in North America, two in South America, one in Asia, one reported data for 49 countries and territories across the five continents, and one from both the USA and Africa. Most of the studies (n = 14) reported data obtained from national registries, and only one provided information collected from hospital medical records. Beyond the actual trend over time, our study reported a pooled global incidence rate (IR) of PTC and FTC in the pediatric age of 0.46 (95% CI: 0.33–0.59) and 0.07 (95% CI: 0.02–0.12) per 100,000 person-years, respectively. The highest IRs were recorded among Caucasian girls, and the lowest in black or other races/ethnicities.ConclusionOur data confirm that DTC in the pediatric population is a rare condition. The pooled IRs of the studies included in this meta-analysis are ~0.5 for PTC, which is the most common histological type when both genders and all age groups are considered. The implementation of a prospective international registry on pediatric DTC, as part of the wider European Registries for Rare Endocrine Conditions, has been recently proposed. In addition to providing relevant information on the clinical behavior of this rare disease, standardization of data collection will be pivotal to fill current gaps and allow an accurate estimation of the real incidence and risk factors of DTC
New national and regional Annex I Habitat records: from #45 to #59
New Italian data on the distribution of Annex I Habitats are reported in this contribution. Specifically, 8 new occurrences in Natura 2000 sites are presented and 27 new cells are added in the EEA 10 km × 10 km reference grid. The new data refer to the Italian administrative regions of Apulia, Campania, Calabria, Lazio, Tuscany, Umbria, Sardinia, and Sicily
Treatment with green tea extract attenuates secondary inflammatory response in an experimental model of spinal cord trauma
In this study, we evaluated the effect of green tea extract (that was administered 25 mg/kg intraperitoneal at 1 and 6 h after injury) in experimental animal model of spinal cord injury. The spinal cord trauma was induced by the application of vascular clips to the dura via a four-level T5–T8 laminectomy. Spinal cord injury in mice resulted in severe trauma characterised by oedema, neutrophilic infiltration and apoptosis. Also, immunohistochemical examination demonstrated a marked increase in immune reactivity for nitrotyrosine. All parameters of inflammation were attenuated by green tea extract. The degree of spinal cord inflammation, nitrotyrosine, poli (ADP-ribosio) synthetase (PARS) and neutrophilic infiltration was markedly reduced. Green tea extract significantly ameliorated the recovery of limb function. Values shown are mean ± SE mean of ten mice for each group. *p < 0.01 versus sham, °p < 0.01 versus spinal cord injury. Taken together, our results clearly demonstrate that green tea extract treatment ameliorates spinal cord injury oxidative stress
- …