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Josep Lloreta

Publications and source records attributed to Josep Lloreta.

27 records · Page 2Linked to original sources
PubMed2002

Effects of intense pulsed light on sun-damaged human skin, routine, and ultrastructural analysis.

BACKGROUND AND OBJECTIVE: New, non-ablative methods can be used in skin rejuvenation. Histologic analysis of non-ablative IPL effects on facial, sun-damaged skin. STUDY DESIGN/MATERIALS AND METHODS: Five female subjects, wrinkle class I or II and Fitzpatrick skin types I, II, and III. IPL treatment: once monthly, 560-nm cut-off filters, spot size 8x35 mm, 28-36 J/cm. Routine histology or electron microscopy on 2-mm punches, before treatment and then 1 week, 3 months, and 12 months. RESULTS: Pre-treatment specimens contained solar elastosis and perifollicular lymphoid infiltrates. Collagen and elastic fibers appeared unaffected by treatment. At 1-week, Demodex organisms appeared coagulated. CONCLUSIONS: Under these conditions, IPL induces minimal morphologic changes in mildly sun-damaged skin. Some esthetic improvement may be secondary to clearing of Demodex organisms and reduction of associated lymphocytic infiltrate.

Collagen↗
PubMed2001

Prediction of recurrence and nucleolar features in node-negative breast carcinoma, ductal type, grade II. An ultrastructural study.

One-third of patients with node-negative breast carcinoma develop a local recurrence that will decisively influence their outcome. We conducted this quantitative ultrastructural study to determine the value of nucleolar features in predicting recurrence of node-negative breast carcinomas. Forty-three node-negative infiltrating duct carcinomas were examined by means of electron microscopy. The number of cells with three or more nucleoli (N3), percentage of nucleoli contacting the nuclear membrane (NC), patient age, tumor size, grading, treatment, follow-up time, development of recurrence, and status were recorded. There were no differences in patient age, tumor grade, or modality of surgical treatment. Significant differences were found among patients with and without recurrence for N3 ( P=0.02), NC ( P=0.01), and tumor size ( P=0.01). For N3, the positive predictive value (PPV) was 64.3, and the negative predictive value (NPV) was 72.4 (sensitivity=52.9%; specificity=80.8%; P=0.04). For NC, the PPV was 62.5, and the NPV was 74.1 (sensitivity=58.8%; specificity=76.9%; P=0.02). For tumor size, the PPV was 66.7, and the NPV was 64.9 (sensitivity=23.5%; specificity=92.3%; P not significant). Using logistic regression analysis, independent predictive value was shown for N3, NC, and tumor size. The number of nucleoli per cell and the number of cells with nucleoli in contact with the nuclear membrane have independent predictive value for the development of recurrence in lymph node-negative infiltrating duct carcinoma of the breast. Although electron microscopy is a highly accurate method, improving the precision of light microscopic techniques would allow more universal assessment of these nucleolar features.

Adult↗
PubMedDate not supplied

NAT2 slow acetylation, GSTM1 null genotype, and risk of bladder cancer: results from the Spanish Bladder Cancer Study and meta-analyses.

BACKGROUND: Many reported associations between common genetic polymorphisms and complex diseases have not been confirmed in subsequent studies. An exception could be the association between NAT2 slow acetylation, GSTM1 null genotype, and bladder-cancer risk. However, current evidence is based on meta-analyses of relatively small studies (range 23-374 cases) with some evidence of publication bias and study heterogeneity. Associations between polymorphisms in other NAT and GST genes and bladder-cancer risk have been inconsistent. METHODS: We investigated polymorphisms in NAT2, GSTM1, NAT1, GSTT1, GSTM3, and GSTP1 in 1150 patients with transitional-cell carcinoma of the urinary bladder and 1149 controls in Spain; all the participants were white. We also carried out meta-analyses of NAT2, GSTM1, and bladder cancer that included more than twice as many cases as in previous reports. FINDINGS: In our study, the odds ratios for bladder cancer for individuals with deletion of one or two copies of the GSTM1 gene were 1.2 (95% CI 0.8-1.7) and 1.9 (1.4-2.7) respectively (p for trend <0.0001). Compared with NAT2 rapid or intermediate acetylators, NAT2 slow acetylators had an increased overall risk of bladder cancer (1.4 [1.2-1.7]) that was stronger for cigarette smokers than for never smokers (p for interaction 0.008). No significant associations were found with the other polymorphisms. Meta-analyses showed that the overall association for NAT2 was robust (p<0.0001), and case-only meta-analyses provided support for an interaction between NAT2 and smoking (p for interaction 0.009). The overall association for GSTM1 was also robust (p<0.0001) and was not modified by smoking status (p=0.86). INTERPRETATION: The GSTM1 null genotype increases the overall risk of bladder cancer, and the NAT2 slow-acetylator genotype increases risk particularly among cigarette smokers. These findings provide compelling evidence for the role of common polymorphisms in the aetiology of cancer. RELEVANCE TO PRACTICE: Although the relative risks are modest, these polymorphisms could account for up to 31% of bladder cancers because of their high prevalence.

Acetylation↗
PubMedDate not supplied

Manual versus laser micro-dissection in molecular biology.

Molecular studies on whole samples of fresh or frozen tissue do not take into account the heterogeneity of these tissues. In addition to normal cells, precursor lesions and different progression stages may be mixed within a given sample. Usually, the dominant cell population will determine the results and may sometimes mask biologically relevant abnormalities. To obtain more specific information and knowledge on changes within different cell compartments, many techniques have been developed that combine morphological observation and selection with different strategies for specific cell dissection. In this review, the most important micro-dissection methods are put into perspective, and some requirements and limitations are discussed with regard to sample fixation, staining, dissection and molecular analysis.

Cell Separation↗
PubMedDate not supplied

The "oil well analogy" as a comprehensive interpretation of factors leading to muscle injury and wasting.

Muscle abnormalities involved in chronic obstructive pulmonary disease (COPD) or the changes leading to muscle wasting and cachexia in neoplastic patients have a remarkable clinical impact, but their study is complex and findings are sometimes paradoxical. In this review, the main factors influencing muscle wasting and muscle abnormalities found in chronic diseases such as COPD are regarded in the light of a comprehensive approach. All this changes work in a complex, multifactorial manner, and experimental or observational approaches must take this fact into consideration. Two concepts that may be helpful in this regard are the "muscle compartment theory," by which different muscle groups, individual muscles, or muscle areas may react differently to a variety of stimuli and pathogenic factors, and the "oil well analogy," which reflects the complexity and variability of the energy resource depletion mechanisms in cells and tissues, leading to structural remodeling and functional adaptation or impairment.

Humans↗
PubMedDate not supplied

Large atypical melanocytic nevi in recessive dystrophic epidermolysis bullosa: clinicopathological, ultrastructural, and dermoscopic study.

A 3-year-old boy with recessive dystrophic epidermolysis bullosa developed a rapidly growing, large, acquired irregular melanocytic nevus on the lower aspect of the back. The lesion was clinically atypical and fulfilled the criteria for a malignant melanocytic proliferation. A complete surgical excision was performed. Histopathologic examination disclosed a compound melanocytic nevus without melanocytic atypia. Ultrastructural examination showed melanocytic cells located both at the roof and the floor of the blister. Several months later, three pigmentary lesions with a similar clinical appearance developed. Periodic clinical and dermoscopic examinations were recommended. Dermoscopic examination disclosed a globular pattern with brown globules and black dots distributed all over the lesions. The lesions also exhibited blue-greyish dots and multiple rounded white structures corresponding to milia-like cysts. No dermoscopic features suggestive of malignancy were noted. Acquired melanocytic nevi showing atypical clinical features have been reported to occur in areas of blistering in patients with epidermolysis bullosa. These nevi appear as large, asymmetrical pigmentary lesions with irregular borders. Initially, they are very dark in pigmentation, with color variegation and loss of pigment, and even becoming papillomatous over time. Histopathologic examination can show features of compound/junctional nevus as well as persistent/recurrent nevus. The concept of "epidermolysis bullosa nevus" has been proposed to define these peculiar lesions. The clinical, histopathologic and ultrastructural features of these nevi are reviewed. The usefulness of dermoscopic examination in the routine diagnosis and follow-up of these lesions are stressed.

Child, Preschool↗
PubMedDate not supplied

Primitive round cell liposarcoma of the omentum: diagnostic value of ultrastructural study.

A 25-year-old woman presented with abdominal distension first observed 1 month earlier. She had a rapidly growing omental tumor that was eventually diagnosed as round cell liposarcoma by ultrastructural examination. This case illustrates the importance of ultrastructural study and the limitations of immunohistochemistry in the diagnosis of such tumors, particularly when they grow in unusual locations.

Adult↗