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Biomedical subjects

C Vincenzi

Publications and source records attributed to C Vincenzi.

At least 19 recordsLinked to original sources
PubMed2005

Permanent alopecia after busulfan chemotherapy.

Systemic chemotherapy is a well known cause of reversible hair loss. Busulfan chemotherapy, however, is responsible for a permanent alopecia that usually occurs in bone marrow transplant patients. We report two patients with permanent alopecia due to busulfan chemotherapy. Both patients had a diffuse alopecia characterized by greatly reduced hair density with short, thin hair. The pathology showed reduced follicular density in the absence of fibrosis, suggesting that alopecia may result either from hair follicle stem cell destruction or from acute damage to the keratinocytes of the lower portion of some follicles.

Adult↗
PubMed2003

Morphological approach to hair disorders.

The Workshop on the morphological approach to hair disorders brought together a group of clinicians involved in hair biology research. Six speakers spoke on a range of topics that can be grouped broadly into a central theme. It summarizes the evolution of medical research. The section by Tosti and coworkers describes a patient with a new unique syndrome. The section by Ferrando and colleagues provides a framework in which patients with rare hair disorders can be classified. The section by Whiting tries to define the normal anatomy of the hair follicle and both horizontal and vertical sections. It is only when normal anatomy has been absolutely defined that pathological deviations can be recognized. The section by Sinclair and coworkers attempts to estimate the reliability of histological diagnosis so that its true value of pathology can be recognized. The section by Zlotogorski and coworkers shows how accurate clinical and histological definition of disease acts as the cornerstone for gene discovery techniques. Once a causative mutation is found and a gene product identified, then the biological consequences of the altered protein product can be studied and the impact of the abnormal molecular function on hair biology can be understood. It is hoped that improved understanding of hair disease will then lead to useful therapeutic interventions. The final section by Leroy and Van Neste highlights the difficulties of evaluating therapeutic interventions in hair loss disease and proposes a new technique.

Alopecia↗
PubMed2001

Hair diameter diversity: a clinical sign reflecting the follicle miniaturization.

BACKGROUND: The degree of androgenetic alopecia is generally evaluated either by global clinical scales or time-consuming methods like phototrichogram or histological studies. We describe a new clinical and reliable scoring method based on hair diameter diversity. OBSERVATIONS: (1) The clinical macroscopic scoring we propose for hair density was significantly correlated with Hamilton classification and with histological hair density. (2) Diversity in hair diameter was the main and most accurate clinical parameter linked to follicle miniaturization. (C) The anagen-telogen ratio decreased in parallel with the decrease in clinical hair density score. CONCLUSIONS: Considering that hair follicle miniaturization is the key point during androgenic alopecia onset and development, diversity in hair diameter represents an important feature to consider as an accurate clinical sign reflecting hair follicle miniaturization. Moreover, diversity in hair diameter seems to be an easily accessible and reliable parameter that should be taken into consideration for further characterization of hair disorders. By itself, we believe that this clinical feature constitutes a new tool of substantial help for the diagnosis and management of androgenic alopecia.

Adult↗
PubMed2000

Provocative use testing of methyldibromo glutaronitrile in a cosmetic shampoo.

Methyldibromo glutaronitrile (1,2-dibromo-2,4-dicyanobutane, MDGN) is a component of Euxyl K400, a broad-spectrum preservative increasingly used in cosmetics over the last 10 years. Contact allergy to MDGN is not uncommon, with leave-on cosmetics and moistened toilet tissue being the most important sources. Rinse-off products have rarely been reported to elicit allergic reactions in patients sensitized to MDGN and shampoos have only been implicated in hairdressers. To determine whether subjects sensitized to MDGN would react in a provocative use test with a shampoo containing the preservative, we asked 12 pre-sensitized subjects to use a shampoo containing 0.02% MDGN for a period of 9-13 weeks. During this time, none of the subjects showed any skin reactions indicative of contact allergy. The results of this study provide evidence to support that a shampoo product containing 0.02% MDGN may safely be used by most individuals who are presensitized to MDGN.

Adolescent↗
PubMed2000

Transplantation potential of peripheral whole blood primed by VACOP-B chemotherapy plus filgrastim (r-metHuG-CSF) in patients with aggressive non-Hodgkin's lumphoma.

Large volumes of peripheral blood need to be processed to obtain sufficient stem cells for hematopoietic rescue after myeloablation, and more than one leukapheresis is necessary in most patients. We conceived the feasibility of harvesting sufficient numbers of hematopoietic cells from the whole blood, obtainable by venaepunctures, of patients treated with a standard dose chemotherapy regimen for high-grade non-Hodgkin's lymphoma. We evaluated the kinetics of mobilization, amount and quality of hematopoietic cells released into circulation during VACOB-B chemotherapy (which consists of a 12-week program), and G-CSF in 6 patients with aggressive non-Hodgkin's lymphoma. The median number of granulocyte-macrophage colony-forming cells (GM-CFC) x 10(3)/ml of blood (range), were 1.9 (0.3-8), and 1.16 (0.2-3.2) after the 7th and 11th weekly dose of drugs, respectively, showing an increase of 19- and 12-fold over patients' prechemotherapy values and of 53- and 33-fold over normal controls (p < 0.001). The median number of CD34+ cells x 10(3)/ml of blood (range), at the 7th and 11th cycle, was 135 (53.7-240.9) and 79.8 (69-173.5), respectively, showing an increase of 10- and 13-fold over patients prechemotherapy values (p < or = 0.04) and of 300- and 179-fold over normal controls (p < or = 0.001). Long-term culture initiating cells (LTC-IC) were released into circulation together with hematopoietic progenitors. We estimated that 1 liter of peripheral blood could yield on average 1.8 x 10(6)/kg CD34+ cells and 2 x 10(4)/kg GM-CFC with LTC-IC frequency comparable to a bone marrow harvest. These figures may be considered sufficient for hematopoietic rescue after myeloablation or hematopoietic support after high-dose chemotherapy.

Adult↗
PubMed1999

Screening of high shear mixer melt granulation process variables using an asymmetrical factorial design.

The effects of process conditions on the granulometric characteristics of a placebo formulation prepared in a 10 l high shear mixer by single-step melt granulation were studied. The factors under investigation were: binder grade, mixer load, presence of the deflector (all of analysed at two levels), binder concentration, impeller speed, massing time, type of impeller blades (these four at three levels) and jacket temperature (considered at four levels). Two granule characteristics were analysed: the geometric mean diameter and the percentage of particles finer than 315 microm. In order to screen simultaneously the above-mentioned factor levels, an asymmetrical factorial design was adopted, which allowed the reduction in the number of runs from 2592 to 25. Additionally, this technique permitted the selection of the factor levels which have the major 'weight' on the two granule characteristics under study. Two additional trials were performed to attest the screening validity.

Chemistry, Pharmaceutical↗
PubMed1999

Sensitization to thimerosal in atopic children.

Thimerosal is an organic mercurial compound widely used as a preservative in vaccines, eyedrops, and contact lens cleaning and storage solutions. 5 infants, 2 female and 3 male, ranging in age from 7 to 28 months and affected by atopic dermatitis (AD) diagnosed according to the Hanifin and Rajka criteria, experienced an exacerbation of their clinical condition 2-10 days after mandatory vaccinations with vaccines containing thimerosal. Cutaneous lesions of nummular eczema appeared on the trunk, limbs and face. All patients were patch tested with serial dilutions of thimerosal in petrolatum. A positive patch test reaction to thimerosal 0.1% pet. was observed in all 5 children. 3 of them also showed a positive reaction at 0.01% and 0.05% pet. Despite their thimerosal-hypersensitivity, all children completed the entire series of mandatory vaccinations, care being taken to use different needles for injection and aspiration of the vaccine. The 2-year follow-up did not reveal other episodes of exacerbation of the AD after vaccination. The present study confirms the high frequency of sensitization to thimerosal in atopic children and suggests that vaccination can cause clinical symptoms in sensitized children. Nevertheless, sensitization to thimerosal does not prevent children from continuing with mandatory vaccinations.

Child, Preschool↗
PubMed1998

Contact dermatitis caused by sesquiterpene lactones.

BACKGROUND: Compositae dermatitis involves workers such as gardeners, florists, and farmers, and less commonly people not employed in occupations at risk. OBJECTIVE: To report a case of contact sensitization caused by Compositae, the source of sensitization being both pesticides and plants. METHODS: A 65-year-old man, whose hobby was gardening, was affected by a chronic eczema of the face and the hands for 6 months that reoccurred after using fertilizers and handling plants. Patch tests with the International Contact Dermatitis Research Group standard series, the plants series and pesticides series (Hermal Trolab) were performed. RESULTS: We found the following positive reactions at day 2 and day 3: sesquiterpene lactone mix, 0.1% in petrolatum; arnica tincture, 20% in petrolatum; pyrethrum, 2% in petrolatum; captafol, 0.1% in petrolatum. CONCLUSION: Pyrethrum and its derivatives are made from Compositae plants; the arnica tincture is obtained from Arnica montana, which is also a member of the Compositae family. In our patient, the clinical manifestations were certainly caused by the exposure to sesquiterpene lactones, confirmed by the positive patch test to sesquiterpene lactone mix.

Aged↗
PubMed1998

Regulation of the proliferative potential of cord blood long-term culture-initiating cells (LTC-IC) by different stromal cell lines: implications for LTC-IC measurement.

BACKGROUND AND OBJECTIVE: Long-term culture-initiating cells (LTC-IC) are the best available approximation to an in vitro assay of stem cells in humans although they still represent a heterogeneous population in terms of proliferative capacity and sensitivity to different growth factors. Human umbilical cord blood (CB) is rich in hemopoietic progenitor cells, as measured by clonogenic assays and contains stem cells capable of reconstituting the marrow after ablation in clinical transplantation. We evaluated the influence of culture conditions on the in vitro behavior of LTC-IC from CB. DESIGN AND METHODS: LTC-IC were evaluated in long-term cultures, comparing two types of murine stromal cell lines: M2-10B4 and M2-10B4 transfected with cDNAs for human G-CSF and IL-3. RESULTS: Two and five fold higher numbers of terminally differentiated cells were produced during nine weeks of culture of CB mononuclear or CD34+ cells respectively, in cultures containing a M2-10B4 IL-3 G-CSF cell line compared to cultures containing the parental cell line. Likewise, a higher number of colony-forming cells (CFC) were detected in the supernatant of cultures with the transfected cell line. In contrast, the number of CFC generated within the stromal layer, after 5 or 9 weeks of culture, was significantly higher in cultures on M2-10B4 cells than those on M2-10B4 IL-3 G-CSF. INTERPRETATION AND CONCLUSIONS: Our results show that the proliferative capacity of CB LTC-IC can be strongly influenced by culture conditions and that the frequency of LTC-IC estimated using these cell lines as stromal support is not identical.

Cell Communication↗
PubMed1997

Diffuse hypertrichosis during treatment with 5% topical minoxidil.

Five women affected by androgenetic alopecia developed severe hypertrichosis of the face and limbs after 2-3 months of treatment with 5% topical minoxidil. Minoxidil was discontinued and in all patients the hypertrichosis disappeared from the face and arms after 1-3 months, and from legs after 4-5 months. Systemic absorption of minoxidil, and a high sensitivity to minoxidil of the follicular apparatus in these areas, is hypothesized.

Administration, Cutaneous↗
PubMed1997

Contact sensitization to sunscreens.

BACKGROUND: Para aminobenzoic acid (PABA) derivatives and cinnamate are chemical sunscreens that protect against UVB (290 to 320 nm). They may occasionally produce contact and photocontact sensitization. OBJECTIVE: To report a sensitization to octyl-dimethyl-PABA and photosensitization to 2-ethylhexyl-p-metossicinnamate in a 31-year-old man. METHODS: A patient with a 3-year history of a relapsing dermatitis involving the face, neck, legs, and knees is reported. The eruption had recurred every summer after sunlight exposure. Patch tests with International Contact Dermatitis Research Group (IC-DRG) standard series and the photopatch series (Hermal-Trolab, Reinbek, Germany) using Finn chambers on Scanpor (Norgesplaster A/S, Oslo, Norway) were carried out. RESULTS: We found a positive reaction to Balsam of Peru, fragrance mix, Escalol 507, and Parsol MCX (Hermal-Trolab, Reinbek, Germany). Photopatch test revealed a positive reaction only for Parsol MCX. CONCLUSION: The incidence of allergic contact dermatitis to sunscreens is considered low. Recently sunscreens patch test concentrations have been increased from 2% to 10%. These higher percentages will probably permit the identification of more cases of sunscreens allergy in the near future.

4-Aminobenzoic Acid↗