ABSTRACT
BACKGROUND: The term hypomineralisation of molars and incisors (MIH), introduced in 2001 by Weerheijm et al., describes a clinical state of hypomineralisation of permanent molars with frequent involvement of the incisors. MIH is considered a global dental problem with a prevalence ranging from 2.4% to 40.2% in the entire world paediatric population. The continuous increase in the prevalence of enamel anomalies, including MIH, indicates the need to define new intervention protocols based on the technological advances that are revolutionising paediatric dentistry. The use of ozone associated with the selective and minimally invasive excavation of the dental tissue combines the antibacterial properties of the gas with an ultra-conservative approach aimed at the maximum conservation of the dental tissue. The operative protocol described can be an important tool in the prevention and treatment of MIH. The aim of this work is to illustrate an operative clinical protocol based on the combined use of selective excavation and ozone for the treatment of carious lesions in paediatric patients with MIH.
Subject(s)
Dental Caries , Dental Enamel Hypoplasia , Humans , Child , Dental Enamel Hypoplasia/epidemiology , Dental Caries Susceptibility , Dental Caries/epidemiology , Molar/pathology , Incisor/abnormalities , PrevalenceABSTRACT
The interaction of the porphyrin derivative H2TCPPSpm4, having spermine pendants in the four meso positions, with the G-quadruplex (GQ) structure formed by the DNA aptamer TGGGAG has been investigated by means of UV, electronic circular dichroism and PAGE studies. The results reported here demonstrate that the porphyrin derivative is capable of stabilizing or destabilizing the higher-ordered structures of parallel GQs, depending on the method used to reach their relative stoichiometry (titration vs. single addition). Noteworthily, when two equivalents of H2TCPPSpm4 were mixed directly with one equivalent of the (TGGGAG)4 GQ to reach a 2 : 1 H2TCPPSpm4 : GQ ratio T1/2 higher than 80 °C was also observed confirming the presence of higher-ordered GQ structures.
Subject(s)
G-Quadruplexes , Porphyrins/chemistry , Spermine/chemistry , Aptamers, Nucleotide/chemistry , Base Sequence , Circular Dichroism , Electrophoresis, Gel, Pulsed-Field , Oligonucleotides/chemistry , Phase Transition , Spectrophotometry, UltravioletABSTRACT
A number of 5'-and 3'-glycoconjugates of the oligonucleotide (5')d(TGGGAG)(3') have been synthesized, exploiting fully automated, online phosphoramidite-based solid phase strategy, as potential anti-HIV-1 agents. The thermodynamic stability of the resulting quadruplexes has been investigated by thermal denaturation studies, via a detailed CD Q1 analysis.
Subject(s)
Anti-HIV Agents/chemistry , Glycoconjugates/chemistry , HIV-1 , Oligodeoxyribonucleotides/chemistry , Anti-HIV Agents/chemical synthesis , Glycoconjugates/chemical synthesis , Guanosine/genetics , Oligodeoxyribonucleotides/chemical synthesis , Sugar Phosphates/chemistryABSTRACT
The aim of our study was to verify the impact of work risk factor in causing cutaneous neoplasia on a group of patients and to assess the risk of exposure to UV on outdoor workers. The survey was divided in three phases: a) Questionnaire, b) Dermatological clinical examination. c) Exposure measurement by spectral radiance method (mW/cm2). 248 subjects were enrolled, 100 of which affected by basal cellular carcinoma (BCC) (68% M and 32% F: mean age 70 +/- 11.93 y) 130 by melanoma (42% M and 58% F; mean age 53 +/- 17.35 y) and 18 by squamous cellular carcinoma (33% F and 67% M: mean age 78 +/- 11.41 y). In addiction 22 healthy male subjects exposed to UV were examined (mean age 38.59 +/- 13.65 y; specific working age 11.88 +/- 10.92 y). The assessment of UV exposure was performed over a 24 days timeframe during summer 2007, all over the working day. Furthermore, maximum allowed exposure time (t(max)) without protection was calculated according to ACGIH guidelines in order to prevent cutaneous alterations. It turned out that the UV exposure, both in working and spare time, is the root cause for squamous cellular cancer developing. Furthermore our results proved that also BCC is related to the overall UV exposure. No clear link to the UV exposure was found for cutaneous melanoma. No precancerous lesions were observed on shortly exposed subjects. The measurements performed revealed, as expected, lower exposure during first and last hours of the day without any particular constrain on t(max), and maximum exposure in the timeframe between 10:00 AM and 4:00 PM. Therefore, it is necessary to pay higher attention to the UV exposure and related consequences on employees health in order to provide with the most suitable preventing measures such the usage of protections depending from the requested exposure time.
Subject(s)
Occupational Diseases/epidemiology , Occupational Exposure/adverse effects , Skin Neoplasms/epidemiology , Ultraviolet Rays/adverse effects , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Occupational Diseases/etiology , Risk Assessment , Risk Management , Skin Neoplasms/etiologyABSTRACT
A systematic study to evaluate the ability of 5'-DNA-3'-p-(N)-PNA-(C) chimeras to form triple helix structures has been undertaken. Preliminary results carried out on a 16-mer chimera with three PNA monomers at the 3'-end showed the formation of a stable DNA-PNA/DNA/DNA triplex, having similar conformational behaviour to a canonical DNA/DNA/DNA triplex.
Subject(s)
DNA/chemistry , Oligodeoxyribonucleotides/chemistry , Peptide Nucleic Acids/chemistry , Binding Sites , Chimera , Circular Dichroism , Nucleic Acid ConformationABSTRACT
Oligonucleotides with a 3'-3' inversion of polarity site assured by one lysine residue have been synthesized, characterized and used as third strands in alternate strand triple helix formation. UV melting studies and molecular mechanics calculations have been carried out to investigate the stability and the geometry of these new triplexes.
Subject(s)
DNA/chemistry , Lysine/chemistry , Oligonucleotides/chemistry , Base Sequence , Drug Stability , Models, Molecular , Nucleic Acid Conformation , Spectrum Analysis , TemperatureABSTRACT
Gluco- and ribosylation of the bases of sugar protected inosine and uridine were investigated, obtaining only adducts with beta-configuration at the new glycosidic carbon; stereospecific insertion of a sugar moiety at the 1-N of inosine was achieved either using a Mitsunobu approach (for ribosylation) or by direct coupling of 1-alpha-bromoglucose 13 with 2',3',5'-tri-O-acetylinosine for glucosylation. 1-(beta-D-glucosyl)-inosine, chosen as starting substrate for glucosylated analogs of cyclic IDP-ribose, was phosphorylated at the primary hydroxyls and tested in intramolecular pyrophosphate bond formation.
