Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
Add more filters










Publication year range
1.
Clin Ter ; 171(4): e288-e290, 2020.
Article in English | MEDLINE | ID: mdl-32614359

ABSTRACT

Dermatitis artefacta is a psychosomatic disorder characterized by cutaneous lesions that are self-inflicted by the patient, apparently due to itchy sensation. Usually, the patient denies any direct involvement with this condition and is rarely conscious of the underlying psychosomatic etiology. Authors report a case of a flight assistant with hypertrophic scars, symmetrically located on both upper arms. She referred chronic itchy sensation localized at the site where lesions were present; she referred relief only through continuous and forceful scratching. Considering the clinical history and after excluding other dermatological disorders, the diagnosis of dermatitis artefacta was made.


Subject(s)
Dermatitis, Occupational/diagnosis , Self-Injurious Behavior , Adult , Arm , Dermatitis, Occupational/etiology , Female , Humans , Pruritus/diagnosis
3.
Carbohydr Polym ; 209: 328-337, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-30732815

ABSTRACT

The aim of this research activity was based on the revalorization of Amplodesmos mauritanicus (Diss), an African grass largely presented in the Algerian territory. Diss stems were selected as native botanic material for the extraction of cellulose nanocrystals (CNC). Two different pretreatment steps were carried out to extract CNC from Amplodesmos mauritanicus stems and the following acidic hydrolysis procedure allowed to extract/obtain cellulose nanocrystals in aqueous suspension. The effect of the two different pretreatments, based essentially on chemical or enzymatic treatments, were deeply investigated and the properties compared. Field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) were considered for the characterization of raw material, chemical or enzymatic treated Diss stems and CNC extracted from both chemical and enzymatic pretreated cellulose.


Subject(s)
Cellulose/chemistry , Cellulose/isolation & purification , Nanoparticles/chemistry , Poaceae/chemistry , Cellulose/metabolism , Endo-1,4-beta Xylanases/metabolism , Hydrolysis , Polygalacturonase/metabolism , Temperature
4.
Carbohydr Polym ; 149: 357-68, 2016 Sep 20.
Article in English | MEDLINE | ID: mdl-27261760

ABSTRACT

Novel gluten based bionanocomposites reinforced with cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) extracted from sunflower stalks by respectively a steam explosion treatment and a hydrolysis procedure, were prepared by casting/evaporation. The extracted cellulose nanomaterials, both CNC and CNF, were embedded in gluten matrix and their effect was investigated. Morphological investigations highlighted that gluten based bionanocomposites showed a homogenous morphology, the absence of visible cellulose nanoreinforcements, and the presence of holes for Gluten_CNF nanocomposites. Gluten_CNF showed a reduction of water vapour permeability coefficients but the values are higher respect to gluten reinforced with CNC. This behaviour could be related to the ability of CNC to increase the tortuous path of gas molecules. Moreover, the results from thermal, mechanical and barrier properties confirmed the strong interactions obtained between CNC and gluten matrix during the process. The study suggested the possibility to re-valorise agricultural wastes with potential applications as reinforcement in polymer matrix bionanocomposites.


Subject(s)
Cellulose/chemistry , Glutens/chemistry , Helianthus/chemistry , Nanoparticles/chemistry , Triticum/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Mechanical Phenomena , Solvents/chemistry , Temperature , Water/chemistry
5.
Carbohydr Polym ; 97(2): 825-36, 2013 Sep 12.
Article in English | MEDLINE | ID: mdl-23911521

ABSTRACT

PVA bio-nanocomposites reinforced with cellulose nanocrystals (CNC) extracted from commercial microcrystalline cellulose (MCC) and from two types of natural fibres, Phormium tenax and Flax of the Belinka variety, were produced by solvent casting in water. Morphological, thermal, mechanical and transparency properties were studied while the respective efficiency of the extraction process of CNC from the three sources was evaluated. The effect of CNC types and content on PVA properties and water absorption capacity were also evaluated. Natural fibres offered higher levels of extraction efficiency when compared with MCC hydrolysis yield. Thermal analysis proved that CNC promotes the crystallization of the PVA matrix, while improving its plastic response. It was also clarified that all PVA/CNC systems remain transparent due to CNC dispersion at the nanoscale, while being all saturated after the first 18-24h of water absorption.


Subject(s)
Asparagaceae/chemistry , Cellulose/chemistry , Flax/chemistry , Nanocomposites/chemistry , Nanoparticles/chemistry , Polyvinyl Alcohol/chemistry , Absorption , Hydrolysis , Mechanical Phenomena , Nanocomposites/ultrastructure , Nanoparticles/ultrastructure , Spectroscopy, Fourier Transform Infrared , Temperature , Tensile Strength , Water/chemistry
6.
Carbohydr Polym ; 97(2): 837-48, 2013 Sep 12.
Article in English | MEDLINE | ID: mdl-23911522

ABSTRACT

Cellulose nanocrystals (CNC) extracted from three different sources, namely flax, phormium, and commercial microcrystalline cellulose (MCC) have been used in a polyvinyl alcohol (PVA) matrix to produce anti-bacterial films using two different amounts of silver nanoparticles (0.1 wt% and 0.5 wt%). In general, CNC confer an effect of reinforcement to PVA film, the best values of stiffness being offered by composites produced using phormium fibres, whilst for strength those produced using flax are slightly superior. This was obtained without inducing any particular modification in transition temperatures and in the thermal degradation patterns. As regards antibacterial properties, systems with CNC from flax proved slightly better than those with CNC from phormium and substantially better than those including commercial MCC. Dynamic mechanical thermal analysis (DMTA) has only been performed on the ternary composite containing 0.1 wt% Ag, which yielded higher values of Young's modulus, and as a whole confirmed the above results.


Subject(s)
Asparagaceae/chemistry , Cellulose/chemistry , Flax/chemistry , Nanocomposites/chemistry , Nanoparticles/chemistry , Polyvinyl Alcohol/chemistry , Silver/chemistry , Absorption , Anti-Bacterial Agents/pharmacology , Calorimetry, Differential Scanning , Escherichia coli/drug effects , Metal Nanoparticles/ultrastructure , Microbial Sensitivity Tests , Nanocomposites/ultrastructure , Nanoparticles/ultrastructure , Silver/pharmacology , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Staphylococcus aureus/drug effects , Temperature , Tensile Strength , Thermogravimetry , Water
7.
Br J Dermatol ; 163(5): 1020-7, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20662835

ABSTRACT

BACKGROUND: Cutaneous pigmentation is regulated by a complex melanogenic network in which both keratinocytes and fibroblasts synthesize growth factors and cytokines. Solar lentigo (SL) is characterized by hyperpigmented lesions occurring on photodamaged skin areas. Despite the association of SL to ultraviolet (UV) exposure, the mechanisms underlying the development of these spots are not completely defined. OBJECTIVES: To analyse the involvement of the fibroblast-derived growth factors, hepatocyte growth factor (HGF), keratinocyte growth factor (KGF) and stem cell factor (SCF) in SL hyperpigmentation; to evaluate whether the photoageing process occurring in fibroblasts could be responsible for the altered expression of these cytokines; and to investigate a new possible role of KGF in regulating pigmentation through the specific induction of melanogenic cytokines by keratinocytes. METHODS: We performed immunohistochemical analysis of HGF, KGF and SCF on SL biopsies. We analysed the mRNA expression of these cytokines using an in vitro model of photoageing induced on fibroblasts. Finally, we evaluated the effects of KGF on the expression of melanogenic cytokines at the mRNA and protein levels on keratinocytes. RESULTS: We found positive staining for HGF, KGF and SCF in the upper dermis of SL lesions and a significant induction of the three cytokines in photoaged fibroblasts. We also demonstrated the contribution of KGF to pigmentation, showing its ability specifically to modulate the expression of SCF in keratinocytes. CONCLUSIONS: Fibroblasts may be persistently activated by UV exposure to release melanogenic growth factors; this inducible cytokine network acts both directly and indirectly through keratinocytes and may contribute to the hyperpigmentation of SL.


Subject(s)
Fibroblast Growth Factor 7/metabolism , Hepatocyte Growth Factor/metabolism , Hyperpigmentation/metabolism , Lentigo/metabolism , Stem Cell Factor/metabolism , Sunlight/adverse effects , Aged , Aged, 80 and over , Biopsy , Blotting, Western , Female , Humans , Hyperpigmentation/etiology , Immunohistochemistry , Lentigo/etiology , Male , Middle Aged , Photosensitivity Disorders/metabolism , Polymerase Chain Reaction/methods , RNA, Messenger/metabolism , Skin Aging/physiology
8.
Theriogenology ; 71(6): 910-9, 2009 Apr 01.
Article in English | MEDLINE | ID: mdl-19121864

ABSTRACT

The effects of fish oil (FO) and vitamin E (vE) dietary supplementation on semen quality, sperm susceptibility to lipid peroxidation, tocopherols content and fatty acid profiles were studied in rabbits. Fifty-two rabbit bucks randomly divided in four groups received a control diet and enriched diets containing either FO (1.5%, w/w), vE (200mg/kg) or both. Semen volume, concentration, motility and viability were analysed at various time-points and the lipid composition was assessed on sperm cells. The phospholipid fatty acid profile was determined: n-6 PUFA were the major fatty acids found, with a proportion of 42%, whereas the n-3 PUFA accounted for nearly 1%, mainly represented by C22:6n-3 (docosahexaenoic acid, DHA). FO supplementation produced a seven-fold increase in the content of DHA in sperm phospholipids and a comprehensive rearrangement of the phospholipid fatty acid composition, while an unexpected negative effect of feeding high level of vE on the proportion of total PUFA was found. Despite the remarkable changes observed in sperm lipid composition, semen quality parameters were not affected by the dietary treatments and the interaction between the two dietary supplements had a significant effect only on sperm concentration. An increase in semen production by ageing and a concomitant rise in sperm susceptibility to in vitro peroxidation was found. alpha- and delta-tocopherol, present in rabbit sperm in similar amount, were not affected by dietary treatment. delta-tocopherol content had a significant linear negative regression with age and showed a significant negative correlation with the susceptibility to peroxidation values.


Subject(s)
Diet , Docosahexaenoic Acids/administration & dosage , Lipids/analysis , Rabbits , Spermatozoa/physiology , Vitamin E/administration & dosage , Animals , Docosahexaenoic Acids/analysis , Fatty Acids/administration & dosage , Fatty Acids/analysis , Fatty Acids, Omega-3/analysis , Fatty Acids, Omega-6/analysis , Fish Oils/administration & dosage , Lipid Peroxidation , Male , Sperm Count/veterinary , Sperm Motility , Spermatozoa/chemistry , Tocopherols/analysis
9.
Theriogenology ; 60(4): 635-45, 2003 Sep 01.
Article in English | MEDLINE | ID: mdl-12832013

ABSTRACT

The ethidium bromide (EtBr) exclusion procedure, a fluorometric method for measuring sperm cell viability, was studied to optimize the use of this technique on boar, rabbit and rooster semen. Diluted semen was used for boars and roosters. Diluted rabbit semen did not allow for reliable fluorescence readings; the interference of granules characteristic of rabbit seminal plasma was suggested as its cause. Therefore, rabbit semen was washed on several Percoll and Optiprep density gradients, with the aim of removing the granules from the sperm suspension. The complete absence of granules was not obtained, however, the best result was provided by the 35/70% Percoll density gradient. Most spermatozoa formed a loose pellet with low contamination. Although the washing procedure resulted in a selective action, Percoll washed semen was used to assess the EtBr procedure. The fluorescence intensities of stained fresh and stained digitonin-permeabilized samples were corrected, respectively, for the nonspecific fluorescence measures of fresh and digitonin-permeabilized samples both unstained. The contribution of the dye was subtracted from the corrected values, then the ratio between the corrected values of fresh and permeabilized cells provided the proportion of damaged cells in the sample. The working cell concentration range giving a constant proportion of damaged cells was set using diluted semen for boars and roosters (8-32 x 10(6) cell/ml) and Percoll washed semen for rabbits (4-16 x 10(6) cell/ml). The reliability of the fluorometric method was compared with the traditional nigrosin-eosin (NE) staining technique. The intactness of sperm samples containing known proportions of fresh and killed cells was measured in defined working cell ranges. For boars and roosters the values determined by fluorometry agreed closely with those determined using the NE method.


Subject(s)
Cell Survival , Chickens , Rabbits , Spectrometry, Fluorescence/methods , Spermatozoa/physiology , Swine , Animals , Ethidium , Fluorescent Dyes , Male
10.
Radiol Med ; 97(5): 341-3, 1999 May.
Article in Italian | MEDLINE | ID: mdl-10432963

ABSTRACT

INTRODUCTION: Plantar fibromatosis, or Ledderhose's disease, is a fibrous proliferation arising within the plantar fascia end exhibiting typical clinical nodular features. The lesion appears as a firm single thickening or a nodule, occasionally painful, localized to the medial portion of the sole of the foot. This unusual condition has not been extensively studied with US and very little has been written about it. MATERIAL AND METHODS: In 1998-99, six patients with plantar fibromatosis were submitted to US with 13 MHz linear array and 20 MHz mechanical annular array probes. All patients were examined in prone recumbency with the probe positioned on the sole of the foot. Only some of them were subsequently submitted to surgery. RESULTS: Plantar fibromatosis exhibited an almost pathognomonic pattern and US proved to be a quick, noninvasive and cost-effective technique to confirm clinical diagnosis. The nodule is typically single and isoechoic, with maximum diameter of about 1 cm, inhomogeneous internal structure and few thin hyperechoic septa. The nodular fibrous proliferation adheres with the major axis along the plantar fascia; it exhibits clear-cut margins and US beam transmission is good. No calcifications or fluid collections are seen within the nodule. Color and power Doppler show no flow inside. CONCLUSIONS: US is an adequate tool for the study of plantar fibromatosis.


Subject(s)
Fibroma/diagnostic imaging , Foot Diseases/diagnostic imaging , Adult , Aged , Female , Humans , Male , Middle Aged , Ultrasonography
12.
Plast Reconstr Surg ; 97(2): 321-6, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8559814

ABSTRACT

Traditional open rhinoplasty produces a scar on the columella. To avoid such a scar and still obtain a wide exposure of the nasal framework, the bilateral paramarginal incisions close to the columella were extended into the nasal floors, and a wide undermining of the base of the columella was performed. The nasal tip with the crura together could then be presented through one of the nostrils. Conditions similar to those of the traditional open rhinoplasty wer thus achieved. The technique has been used in selected patients for 8 years with satisfactory results. In conclusion, the open rhinoplasty without transcolumellar incision can replace the traditional transcolumellar open rhinoplasty technique.


Subject(s)
Rhinoplasty/methods , Adult , Child, Preschool , Female , Humans , Male
13.
G Ital Dermatol Venereol ; 125(6): 255-8, 1990 Jun.
Article in Italian | MEDLINE | ID: mdl-2279751

ABSTRACT

The authors present the case of a patient affected by Lyell's Syndrome and Lymphoma that was revealed in the post-mortem examination. At onset the disease showed mucosal hyperaemia, oedema and erosions. In about ten days macular lesions with vesciculation and bullae appeared on the abdomen. General conditions did not seem to be affected. Three weeks later a fever was noted. No important illness, nor drug assumption were detectable in the history of the patient. At the beginning of the fourth week a dramatic worsening occurred with erythrodermic state and high fever. Death occurred at the sixth week in spite of therapy. Bacteriological and virological examinations were always negative. Post-mortem examination showed retroperitoneal and pelvic neoplastic tissue, involving lumboaortic lymph nodes. Histopathology demonstrated a low grade malignancy non Hodgkin Lymphoma, diffused type with small lymphocytes showing plasmocytic differentiation. The lack of drug intake or infectious disease in the history, underlines the peculiar association between the tumor and the syndrome. Rare cases of TEN associated with lymphoproliferative neoplasm are reported in the literature, and the pathogenetic problem of the syndrome is reviewed.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell/complications , Stevens-Johnson Syndrome/etiology , Humans , Male , Middle Aged
SELECTION OF CITATIONS
SEARCH DETAIL
...