1,720,982 research outputs found
Applicazioni delle biotecnologie in microbiologia clinica
No full textLa biologia molecolare negli ultimi decenni ha rivoluzionato il panorama della
ricerca scientifica e della diagnostica, permettendo di rendere visibili e di
quantificare “entità” delle quali, in un passato non molto lontano, si ignorava
persino l’esistenza. Se fino agli anni ’50 si parlava di presunte proteine in grado
di trasmettere l’informazione genetica, ora si conoscono esattamente le
molecole responsabili del perpetuarsi della vita: l’acido deossiribonucleico
(DNA) e l’acido ribonucleico (RNA). In un susseguirsi incessante di scoperte
l’uomo prende pieno possesso della chimica, della biologia e della struttura
degli acidi nucleici. L’essenza di ogni forma di vita diventa decifrabile in pochi e
semplici elementi: le basi azotate, che costituiscono una catena fitta di
informazioni e legami chimici, codificano, di tre in tre, gli aminoacidi da
inglobare nelle nascenti proteine. È la stele di Rosetta per decriptare il codice
genetico: il gene da entità astratta prende forma, sostanza e dimora. Il processo
di “modernizzazione” della scienza della vita è cominciato: nasce la biologia
molecolare che in pochi anni rivoluziona l’indagine scientifica in campo medico,
farmaceutico, alimentare, ambientale... Dopo l’introduzione della reazione di
amplificazione a catena (PCR) del DNA, avvenuta negli anni ’80, il codice
genetico della vita diventa “visibile” e a “portata d’uomo”: una singola molecola
viene replicata in modo esponenziale milioni di volte, milioni di copie di un gene
sono disponibili per essere studiate, comprese e clonate. I geni di interesse
vengono inseriti in vettori ricombinanti, a loro volta ospiti di quelli che oggi
chiamiamo organismi geneticamente modificati (OGM). In tutti i laboratori del
mondo prendono vita nuove entità biologiche, con geni ancestrali frutto di una
selezione milionaria, ma in combinazioni che solo l’uomo ha saputo creare. E
non solo. Nel XXI secolo l’uomo riesce anche a sequenziare il proprio genoma,
a scrivere il vocabolario della sua storia biologica, pur senza comprendere
pienamente il significato di ogni “parola”. Ma, indipendentemente dalla
comprensione di queste “parole”, è opportuno chiedersi quanto il contesto
ambientale, gli eventi contingenti, limitino e condizionino la totipotenza del
nostro codice genetico. Sotto questo profilo, in una visione deterministica,
l’uomo potrebbe presuntuosamente credere di aver raggiunto lo scopo, quello
di prevedere l’insorgere di malattie o patologie, quello di modellare la vita
secondo i propri gusti e desideri... Ma la persuasione di ciò è lontanissima dalla
realtà cosmica, policromatica, mutevole di cui siamo pervasi. Le conoscenze di
biologia molecolare acquisite in questi ultimi anni ci possono aiutare ad
indagare, capillarmente, i meccanismi alla base di molte malattie, ad accelerare
i tempi per una diagnosi, a disegnare farmaci personalizzati, a migliorare le
caratteristiche di un prodotto alimentare o di un vegetale necessario per
l’alimentazione umana e animale, ma non potranno mai prevedere, secondo
una visione riduzionista della scienza, il nostro destino biologico.not availabl
Response to Comment on Olioso D. et al. "Effect of Aerobic and Resistance Training on Circulating Micro-RNA Expression Profile in Subjects with Type 2 Diabetes. J Clin Endocrinol Metab 2019; 104(4):1119-1130" by Chirumbolo S
No full text[no abstract available
A dynamic network model of the similia principle
No full textThe use of drugs in high dilutions and the principle of similarity (or "similia") are two basic tenets of homeopathy. However, the plausibility of both is a subject of debate. Although several models have been proposed to explain the similia principle, it can be best understood and appreciated in the framework of complexity science and dynamic systems theory. This work applies a five-node Boolean network to show how self-organization and adaptation are relevant to rationalizing this traditional medical principle. Simulating the trajectories and attractors of the network system in the energy state-space provides a rudimentary and qualitative illustration of how targeted external perturbations can have pathological effects, leading to permanent, self-sustaining alterations. Similarly, changes that conversely enable the system to find its way back to the original state can induce therapeutic effects, by causing specific shifts in attractors when suitable conditions are satisfied. Extrapolating these mechanisms to homeopathy, we can envisage how major changes in the evolution of homeodynamic systems (and, eventually, healing of the entire body) can be achieved through carefully selected remedies that reproduce the whole symptom pattern of the ill state
Arnica Montana effects on gene expression in a human macrophage cell line. Evaluation by quantitative Real-Time PCR
Full text linkPremesse:
l'Arnica Montana è un preparato tradizionale popolare molto usato in medicina complementare, anche per le sue proprietà curative.
Nonostante la sua azione riconosciuta in ambito clinico nelle diverse dosi, gli aspetti molecolari che favoriscono la guarigione delle ferite
devono essere ancora chiariti. Per cercare di ovviare a questa mancanza, abbiamo valutato l'estratto della pianta, in un ampio spettro di
diluizioni, nelle cellule umane THP-1, differenziate tra macrofagi completamente sviluppati e macrofagi aVENTl fenotipo alternativo IL-4, coinvolto nella ricomposizione e nella guarigione dei tessuti.
Metodi:
L'analisi PCR (Polymerase Chain Reaction) è stata applicata per analizzare i cambi di espressione di un pannello di "geni chiave", soprattutto citochine. recettori e fattori di trascrizione.
Risultati:
Sui macrofagi sviluppati verso il fenotipo che favorisce la guarigione, l'Arnica Montana influenza l'espressione di svariati geni. In particolare il gene CXCL1 ha mostrato l'incremento di espressione più evidente, mentre il gene CXCL2, il gene IL8 e quello della proteina BMP2 sono risultati modificati verso l'alto, suggerendo la possibilità di un effetto positivo dell'Arnica Montana sulla selezione dei neutrofili e sull'angiogenesi. A sua volta, il gene MMP1, esprimente una metalloproteinasi in grado di suddividere i substrati extra-cellulari, risulta regolata verso il basso.
La maggior parte dei risultati ottenuti mostra un andamento non lineare della relazione dose-effetto.
Conclusioni:
Questo studio esplorativo fornisce una nuova visuale nello studio del meccanismo di azione di Arnica Montana come rimedio per favorire la guarigione, poiché alcuni dei geni da essa modificati sono geni regolatori della ricomposizione dei tessuti, del grado di infiammazione e della chemiotassi.Background:
Arnica montana is a popular traditional remedy widely used in complementary medicine, also for its
wound healing properties. Despite its acknowledged action in clinical settings at various doses, the
molecular aspects relating to how Arnica montana promotes wound healing remain to be elucidated.
To fill this gap, we evaluated the whole plant extract, in a wide range of dilutions, in THP-1 human
cells, differentiated into mature macrophages and into an alternative IL-4-activated phenotype
involved in tissue remodelling and healing.
Methods:
Real-time quantitative Reverse Transcription Polymerase Chain Reaction (PCR) analysis was used
To study the changes in the expression of a customized panel of key genes, mainly cytokines,
receptors and transcription factors.
Results:
On macrophages differentiated towards the wound healing phenotype, Arnica montana affected the
expression of several genes. In particular CXC chemokine ligand 1 (CXCL1), coding for a chief chemo-
kine, exhibited the most consistent increase of expression, while also CXC chemokine ligand 2 (CXCL2),
Interleukin8 (IL8) and bone morphogenetic protein (BMP2) were slightly up-regulated, suggesting a
positive influence of Arnica montana on neutrophil recruitment and on angiogenesis. MMP1, coding for
a metalloproteinase capable of cleaving extracellular matrix substrates, was down-regulated.
Most results showed non-linearity of the dose-effect relationship.
Conclusions:
This exploratory study provides new insights into the cellular and molecular mechanisms of action of
Arnica montana as a promoter of healing, since some of the genes it modifies are key regulators of
tissue remodelling, inflammation and chemotaxis
Effects of Gelsemium sempervirens L. on pathway-focused gene expression profiling in neuronal cells
Full text linkGelsemium sempervirens L. is a traditional medicinal plant mainly distributed in the southeastern of the United States, employed in phytotheraphy and homeopathy as nervous system relaxant to treat various types of anxiety, pain, headache and other ailments. Although animal models showed its effectiveness, the mechanisms by which it might operate on the nervous system are largely unknown. This study investigated for the first time by a real-time PCR technique (RT-PCR Array) the gene expression of a panel of human neurotransmitter receptors and regulators, involved in neuronal excitatory signaling, on a neurocyte cell line. Materials and methods: Human SH-SY5Y neuroblastoma cells were exposed for 24 h to Gelsemium sempervirens at 2c and 9c dilutions (i.e. 2 and 9-fold centesimal dilutions from mother tincture) and the gene expression profile compared to that of cells treated with control vehicle solutions. Results: Exposure to the Gelsemium sempervirens 2c dilution, containing a nanomolar concentration of active principle gelsemine, induced a down-regulation of most genes of this array. In particular, the treated cells showed a statistically significant decrease of the prokineticin receptor 2, whose ligand is a neuropeptide involved in nociception, anxiety and depression-like behavior. Conclusions: Overall, the results indicate a negative modulation trend in neuronal excitatory signaling, which can suggest new working hypotheses on the anxiolytic and analgesic action of this plant
High-dilution effects revisited. 1. Physicochemical aspects
No full textSeveral lines of evidence suggest that homeopathic high dilutions (HDs) can effectively have a pharmacological action, and so cannot be considered merely placebos. However, until now there has been no unified explanation for these observations within the dominant paradigm of the dose-response effect. Here the possible scenarios for the physicochemical nature of HDs are reviewed. A number of theoretical and experimental approaches, including quantum physics, conductometric and spectroscopic measurements, thermoluminescence, and model simulations investigated the peculiar features of diluted/succussed solutions. The heterogeneous composition of water could be affected by interactive phenomena such as coherence, epitaxy and formation of colloidal nanobubbles containing gaseous inclusions of oxygen, nitrogen, carbon dioxide, silica and, possibly, the original material of the remedy. It is likely that the molecules of active substance act as nucleation centres, amplifying the formation of supramolecular structures and imparting order to the solvent. Three major models for how this happens are currently being investigated: the water clusters or clathrates, the coherent domains postulated by quantum electrodynamics, and the formation of nanoparticles from the original solute plus solvent components. Other theoretical approaches based on quantum entanglement and on fractal-type self-organization of water clusters are more speculative and hypothetical. The problem of the physicochemical nature of HDs is still far from to be clarified but current evidence strongly supports the notion that the structuring of water and its solutes at the nanoscale can play a key role
Effects of Gelsemium sempervirens L. on pathway-focused gene expression profiling in neuronal cells
No full textETHNOPHARMACOLOGICAL RELEVANCE:
Gelsemium sempervirens L. (G. sempervirens) is a traditional medicinal plant mainly distributed in the southeastern of the United States, employed in phytotheraphy and homeopathy as nervous system relaxant to treat various types of anxiety, pain, headache and other ailments. Although animal models showed its effectiveness, the mechanisms by which it might operate on the nervous system are largely unknown.
AIM OF THE STUDY:
This study investigated for the first time by a real-time PCR technique (RT-PCR Array) the gene expression of a panel of human neurotransmitter receptors and regulators, involved in neuronal excitatory signaling, on a neurocyte cell line.
MATERIALS AND METHODS:
Human SH-SY5Y neuroblastoma cells were exposed for 24h to G. sempervirens at 2c and 9c dilutions (i.e. 2 and 9-fold centesimal dilutions from mother tincture) and the gene expression profile compared to that of cells treated with control vehicle solutions.
RESULTS:
Exposure to the G. sempervirens 2c dilution, containing a nanomolar concentration of active principle gelsemine, induced a down-regulation of most genes of this array. In particular, the treated cells showed a statistically significant decrease of the prokineticin receptor 2, whose ligand is a neuropeptide involved in nociception, anxiety and depression-like behavior.
CONCLUSIONS:
Overall, the results indicate a negative modulation trend in neuronal excitatory signaling, which can suggest new working hypotheses on the anxiolytic and analgesic action of this plant
Biological activity of interferon gamma and lipopolysaccharide on the nitric oxide production in C6 astroglioma cells and some unexpected effects of potentization
No full textBackground: The search for new therapeutic approaches with fewer side effects and better treatment efficacy to the Chagas Disease has been a major challenge. Aim: To evaluate the effects of Kalium causticum, Conium maculatum, and Lycopodium clavatum 13 cH in mice inoculated with the Y strain of Trypanosoma cruzi. Materials and methods: In a blind, controlled, randomized study, 102 male Swiss mice, eight weeks old, were inoculated with 1,400 trypomastigotes of the Y strain of T. cruzi and distributed into the following groups: CI (treated with 7% hydroalcoholic solution), Ca (treated with Kalium causticum 13cH), Co (treated with Conium maculatum 13cH), and Ly (treated with Lycopodium clavatum 13cH). The medicines were selected by three homeopaths using Lince Expert System Software (Albuquerque, NM, USA), considering the behavioral characteristics of the mice. The treatments were performed 48 hours before and 48, 96, and 144 hours after infection [1]. The following parameters were evaluated: infectivity, prepatent period, parasitemia peak, total parasitemia, tissue tropism, inflammatory infiltrate, and survival. Results: The prepatent period was greater in the Ly group than in the CI group (p = 0.02). The number of trypomastigotes on the 8th day after infection was lower in the Ca group than in the CI group (p < 0.05). Total parasitemia was significantly lower in the Ca, Co, and Ly groups than in the CI group. On the 12th day after infection, the Ca, Co, and Ly groups had fewer nests of amastigotes and amastigotes/nest in the heart than the CI group (p < 0.05) (Figure-I). A decrease in the number of nests and amastigotes in the intestine were observed in the Ly group compared with the CI group (p < 0.05). In the liver (day 12), Ly significantly prevented the formation of inflammatory foci compared with the other groups. In muscle, Co and Ly decreased the formation of inflammatory foci compared with CI (p < 0.05). Ly afforded greater animal survival compared with CI, Ca, and Co (p < 0.05). The animals in the Co group died prematurely compared with the CI group (p = 0.031). (Figure-II) Conclusion: All of the experimental homeopathic medications with 13cH dynamization studied herein reduced the parasite peak and total parasitemia. Ly had significantly more benefits in the treatment of mice infected with T. cruzi, reducing the number of blood parasites, amastigotes nests in tissue and the number of amastigotes per nest, resulting in the increasing animal survival. The data may contribute to changes in management strategies in individuals with Chagas disease
Phylogenetic analysis of vancomycin-resistant enterococcus faecium genotypes associated with outbreaks or sporadic infections in Italy
No full textPulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to investigate the genetic relatedness of a total of 41 Enterococcus faecium isolates from different backgrounds (hospital outbreaks, n = 9; documented sporadic infections, n = 10; asymptomatic sporadic carriage of hospitalized patients, n = 9; healthy persons, n = 3; non-human sources, n = 10) over the period 1996-2004 in comparison with clones that have spread in Italy since 1993. Thirty six isolates were vancomycin-resistant and five were vancomycin-susceptible. eBURST analysis of MLST sequence types generated two groups: (1) group 1 (27 isolates) forming a clonal complex (CC17) with the predicted founder corresponding to ST17, a genotype identified in 1994, that included esp-positive and -negative clones isolated from hospitalized patients; and (2) group 2 (14 isolates) including esp-negative clones from different sources (hospitalized patients, healthy persons and non-human sources). The hyl gene was found in five strains with different PFGE types, all belonging to group 1, whereas cylA, gelE, and asa1, were not detected in any of the isolates. Our data showed that the evolution of the MLST C1 epidemic lineage has been continuing in several Italian areas and generating new clones with different PFGE patterns. The main, though not the sole, mechanism that has driven this evolution was confirmed to be linked to the presence of the esp gene
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