102,348 research outputs found
Pediatric glaucoma: current perspectives
No full textGiorgio Marchini, Marco Toscani, Francesca Chemello Eye Clinic, Department of Neurological and Movement Sciences, University of Verona, Verona, Italy Abstract: “Childhood glaucoma” is a heterogeneous group of severe pediatric conditions often associated with significant visual loss and characterized by elevated intraocular pressure (IOP) and optic-disk cupping. Successful IOP control is crucial but challenging and most often achieved surgically, with medical therapy playing a supportive role. There are many classifications of childhood glaucoma, but they can simply be divided into primary, in which a developmental abnormality of the anterior chamber angle only exists, and secondary, in which aqueous outflow is reduced due to independent mechanisms that secondarily impair the function of the filtration angle. The worldwide prevalence of childhood blindness ranges from 0.03% in high-income countries to 0.12% in undeveloped countries. The majority of cases do not have an identified genetic mutation and, where the mutation is known, the genes often account for only a small proportion of cases. Several pathogenetic mechanisms are known to contribute to the development of childhood glaucoma. Whatever the cause, it results in a reduced aqueous outflow at the level of the trabecular meshwork. Age of onset and magnitude of the elevated IOP largely determine the clinical manifestation the high variability of clinical manifestations. Glaucoma from any cause in a neonate and infant is characterized by the classic triad of epiphora, photophobia, and blepharospasm, and could be associated with eye enlargement (buphthalmos) and Haab striae. The eye examination, usually performed under general anesthesia, includes: tonometry, anterior-segment examination, gonioscopy, corneal diameter and axial length measurement, dilated fundoscopy with optic-nerve-head evaluation. Medical therapy, considering the high frequency of side effects, is generally used as temporizing IOP-lowering treatment before surgery or as adjuvant treatment postoperatively in case of partially successful procedures for refractory glaucomas. Surgery is the nodal point of the management of refractory childhood glaucoma, so it is crucial to opt for a forward-looking strategy to reach the target IOP and minimize the visual loss. Keywords: childhood glaucoma, congenital glaucoma, glaucoma surgical therapy, childhood visual los
Single-cell/nucleus transcriptomic and muscle pathologies
No full textRecent years have seen a dramatic improvement in RNA and DNA sequencing technologies allowing the analysis of gene expression and chromatin conformation at the single-cell or nuclei level. This permitted to evidence that cells of the human brain may have different genomes, the different cell types living in a tumor or during its development, and many other biological features, promising significant future biomedical and clinical impacts. In this chapter, we will develop the concept of single-cell or nucleus RNA sequencing discussing methods and applications in the field of muscle pathologies. We will focus on all the three types of muscles: skeletal muscle is particularly important to sustain the body and regulate the metabolism, cardiac muscle is fundamental for blood movement within vessels and oxygen and nutrient distribution, and smooth muscle is involved in the maintenance of blood pressure and in the movement of the bolus within the intestine
Application of nanotechnologies in aquaculture
No full textLe nanotecnologie possiedono un vasto potenziale nella produzione di materiali con nuove ed uniche proprietà attraverso il controllo e la manipolazione della materia su scala atomica e molecolare.
Le nanoparticelle giocano un ruolo importante nello sviluppo della nanotecnologia, grazie alle loro caratteristiche uniche hanno favorito la crescita nella produzione di materiali su nanoscala e il loro impiego in molteplici settori. I principali vantaggi derivanti dall’uso delle nanoparticelle sono rappresentati dalle loro ridotte dimensioni ed il loro elevato rapporto superficie/volume che le rendono promotori chiave nella crescita di molti settori industriali e di ricerca.
L’acquacoltura rappresenta il settore in più rapida crescita nell’industria alimentare a livello mondiale, contribuendo in modo significativo alla fornitura mondiale di pesce per il consumo umano.
Per garantire una crescita sostenibile in grado di soddisfare le richieste del mercato globale, l’acquacoltura deve superare gli aspetti negativi legati alla sua stessa attività tra i quali, l’elevata concentrazione di composti organici nelle acque reflue non trattate, l’uso diffuso di antibiotici e la proliferazione di alcuni vettori di malattie. L’utilizzo delle nanotecnologie potrebbe offrire diverse soluzioni per risolvere tali problematiche permettendo uno sviluppo sostenibile dell’attività di acquacoltura. Grazie ad un approccio multidisciplinare che include analisi molecolari, chimiche e microscopiche, questo studio è stato in grado di testare l’utilizzo sicuro e innovativo di due diversi tipi di nanoparticelle in diversi settori dell’acquacoltura.
Sono stati scelti diversi organismi modello (Danio rerio, Sparus aurata, Aedes aegypti e Escherichia coli) considerati come le specie più rilevanti ed utili per questa ricerca.
Questa tesi di dottorato, ha evidenziato sia la grande versatilità sia il sicuro impiego di questi due tipi di nanomateriali per la risoluzione di diverse problematiche legate all’attività dell’acquacoltura. Tutti gli esperimenti sono stati condotti in ambiente controllato e ponendo le basi per studi futuri e possibili applicazioni pratiche nel settore dell’acquacoltura.Nanotechnology has a great potential to create new materials with enhanced properties through the control and manipulation of the matter at the atomic and molecular level.
Nanoparticles (NPs) play an important role in nanotechnology advances, unique NPs characteristics have accelerated the growth in the production of nanoscale materials and the rapid increase of their application in many areas. The major advantages of NPs are represented by their small size and high surface/volume ratio, which make them the key promoters of several industries and research sectors growth. Aquaculture represents the fastest growing food-producing sector in the world and significantly contributes to the world’s supply of fish for human consumption. In order to guarantee a sustainable growth that meets the global needs, aquaculture activity has to overcome some disadvantageous aspects deriving from its own practices, such as the high number of organic compounds in untreated wastewater, the large use of antibiotics and the proliferation of disease vectors. Nanotechnology application could offer different solutions to solve such issues and ensure the sustainable development of aquaculture activity.
Thanks to a multidisciplinary approach that includes molecular, chemical and microscopy analysis, this study was able to test the innovative and safe application of two different types of nanotechnology on different aquaculture aspects. Different model organisms (Danio rerio, Sparus aurata, Aedes aegypti, and Escherichia coli) were chosen as the most relevant and useful species to the present research.
This doctoral thesis highlighted at first, the great versatility and the safe application of these two types of nanomaterial to solve different aquaculture problems. All the experiments were conducted in a controlled aquatic environment laying the foundations for future studies aiming to a practical consequence in aquaculture activity
A SNP at the exon 1 of the Lipoprotein lipase (LPL) gene is associated with milk traits in the Mediterranean River buffalo
No full textLipoprotein lipase is a key enzyme for the lipid metabolism playing a fundamental role in the composition of fat in adipose
tissue as well as in milk. LPL gene was poorly investigated in dairy ruminants, and it has been never studied in river buffalo.
Aims of this work were to explore the genetic diversity of LPL (from exon 1 to 4) in this species; to characterize the gene
promoter; and to achieve an association study with milk traits. Genomic DNA of 14 individual samples of Mediterranean
Italian breed was amplified and sequenced. Thirteen consensus sequences for transcription factors were found. C/EBPα
and Oct-1 are the main regulatory motifs together with LP-α, although a deeper investigation is necessary to elucidate the
role of the latter element, which in buffalo (and ruminants in general) is lacking the downstream cis-acting motifs (LP-β)
compared to human. A total of 11 SNPs have been detected. The SNP g.107A>G was the only polymorphism found at
exon level, therefore a genotyping was achieved by PCR-RFLP in a population of 523 Mediterranean buffaloes. The allele
frequency was 0.63 and 0.37 respectively for the G and A allele. This SNP was significantly associated with n3-PUFA
(P<0.03; 306 individual milk samples), with the GG genotype showing the highest value (+8.25% and +7.14% compared
with AA and AG, respectively). The AA and GG genotypes showed higher values also for the milk yield compared with AG,
but the estimated difference only approached the level of significance (P=0.07). This study is among the first reports that
show an association between milk fatty acids and LPL genotype in ruminants, and it adds further knowledge in the study
of genes involved in the regulation of milk fatty acids composition in river buffalo
Muscle damage and repeated bout effect induced by enhanced eccentric squats
No full textBACKGROUND: Muscle damage and repeated bout effect have been studied after pure eccentric-only exercise. The aim of this study was to evaluate muscle damage and repeated bout effect induced by enhanced eccentric squat exercise using flywheel device. METHODS: Thirteen healthy males volunteered for this study. Creatine kinase blood activity (CK), quadriceps isometric peak torque and muscle soreness were used as markers of muscle damage. The dependent parameters were measured at baseline, immediately after and each day up to 96 hours after the exercise session. The intervention consisted of 100 repetitions of enhanced eccentric squat exercise using flywheel device. The same protocol was repeated after 4 weeks. RESULTS: After the first bout, CK and muscle soreness were significantly greater (P<0.05) than baseline respectively up to 72 and 96 hours. Isometric peak torque was significantly lower (P<0.05) up to 72 hours. After the second bout, CK showed no significant increase (P>0.05), while isometric peak torque and muscle soreness returned to values similar to baseline after respectively 48 and 72 hours. All muscle damage markers were significantly lower after second compared to first bout. CONCLUSIONS: The enhanced eccentric exercise induced symptoms of muscle damage up to 96 hours. However, it provided muscle protection after the second bout, performed four weeks later. Although it was not eccentric-only exercise, the enhancement of eccentric phase provided muscle protection
A comparative study of the mollusc communities of a Mediterranean saltwork (Marsala, Western Sicily.
No full textSaltworks are peculiar artificial ecosystems and holds great interest for basic research. In fact the cooling vat
(the first pond of the evaporating series) is a good example of a relatively closed area and can be considered
an excellent in the field open-air laboratory, namely a mesocosm reproducing a simplified model of the
natural condition of hyperaline lagoons.
The aim of the present work was to analyse the structure, composition and distribution of molluscan
assemblages and to identify the faunistic relationships between the cooling vat and the neighbouring basin of
Stagnone di Marsala, beside considering exchanges between saltwork, Stagnone di Marsala and sea, on soft-
bottom, covered by Cymodocea nodosa. In structural terms, two molluscan communities can be identified.
As regard the saltwork, the community was always characterized by halolimnobic and euryaline species
such as Ventrosia ventrosa, Loripes lacteus, Abra segmentum and Pirenella conica. while the community
inhabiting Stagnone was composed mainly of marine taxa; here a good exchange with the sea is confirmed
by the high values for species richness and diversity gives rise mainly to the presence of marine taxa: e. g
Jujubinus striatus, Dikoleps nitens, Rissoa paradoxa, R. similis, Columbella rustica etc.
The saltwork molluscan assemblage doesn’t seem to be similar to that of the Stagnone. The low specific
richness, the high abundance and the low evenness, showed a pioneer stage of colonization, being poor in
species and dominated by taxa with high abundance and low evennes
Sequencing of lipoprotein lipase gene in the Mediterranean river buffalo identified novel variants affecting gene expression
No full textLipoprotein lipase (LPL) is a key enzyme for lipid metabolism, playing a fundamental role in the composition of fat in adipose tissue and milk. The LPL gene has been seldom investigated in dairy ruminants and barely studied in river buffalo (Bubalus bubalis). The aim of this work was to explore the genetic diversity of LPL and its promoter and to identify functional mutations, using a combined approach based on sequencing, dual-color electrophoretic mobility shift assay, and quantitative PCR. Thirteen consensus sequences for transcription factors were found in the promoter. Eleven SNP were detected, and the attention was focused on the SNP with potential functional effects: g.-446A>G, because the presence of G created a consensus motif for the transcription factor Sp1, and g.107A>G, which was the only exonic SNP. We developed PCR-RFLP methods for genotyping the 2 SNP and calculated the allele frequencies. A strong linkage disequilibrium (D′ = 1; r2 = 0.903) was found between the 2 SNP. The dual-color electrophoretic mobility shift assay demonstrated that only genotype g.-446GG allowed the binding of the Sp1 transcription factor, resulting in overexpression of the gene (~2.5 fold), as confirmed by the quantitative PCR results. Haploinsufficiency is proposed as a regulation mechanism. This study adds further knowledge on the structure of the LPL gene and its expression in river buffalo, with potential effects on milk qualitative and quantitative productio
RELATIONSHIP BETWEEN HBcAg IN SERUM AND LIVER AND HBV REPLICATION IN PATIENTS WITH HBsAg POSITIVE CHRONIC LIVER DISEASE
No full textThe expression of hepatitis B core antigen (HBcAg) in serum and in hepatocytes was evaluated in relation to HBV replication. Fifty chronic HBsAg carriers with histological evidence of liver disease were studied, including 24 HBeAg-positive patients, 2 HBeAg/anti-HBe-negative patients, and 24 anti-HBe-positive cases, two of them with evidence of delta agent infection. Serum HBV-DNA was evaluated in all patients and related to HBcAg examined at the same time in frozen liver biopsies by immunofluorescence and to HBcAg detected in the corresponding serum by a recently developed radioimmunoassay. HBV-DNA was present in serum in 20 (83%) HBeAg-positive patients, all positive for serum HBeAg, whereas liver core antigen was detected in 14 (73%) of 19 cases. Among HBeAg-negative patients, 50% showed the presence of circulating DNA viral sequences, and HBcAg was identified in five of 26 (19%) cases in serum and in six of 24 (25%) in the liver respectively. In 15 patients, liver fragments permitted examination in parallel by immunofluorescence for HBcAg and molecular hybridization for viral DNA in liver cells. A DNA pattern characteristic of viral replication was found in cases with evidence of active virion production, independently from HBeAg and anti-HBe, and in these patients HBcAg was present both in serum and in hepatocytes. In two cases with free HBV-DNA, without evidence of replicative activity, core antigen was not detected in the liver, but in one patient HBcAg was found in the serum. A similar finding was also noted in another patient, in whom the hybridization pattern was consistent with integration of viral genome into high-molecular-weight cellular DNA. Whether serum HBcAg detected in these patients without HBV-DNA in serum reflects the presence of defective viral particles or of core antigen released as a viral protein remains to be determined
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