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M Pluot

Publications and source records attributed to M Pluot.

At least 19 recordsLinked to original sources
PubMed2007

Vibrational spectroscopy studies of formalin-fixed cervix tissues.

Optical histopathology is fast emerging as a potential tool in cancer diagnosis. Fresh tissues in saline are ideal samples for optical histopathology. However, evaluation of suitability of ex vivo handled tissues is necessitated because of severe constraints in sample procurement, handling, and other associated problems with fresh tissues. Among these methods, formalin-fixed samples are shown to be suitable for optical histopathology. However, it is necessary to further evaluate this method from the point of view discriminating tissues with minute biochemical variations. A pilot Raman and Fourier transform infrared (FTIR) microspectroscopic studies of formalin-fixed tissues normal, malignant, and after-2-fractions of radiotherapy from the same malignant cervix subjects were carried out, with an aim to explore the feasibility of discriminating these tissues, especially the tissues after-2-fractions of radiotherapy from other two groups. Raman and FTIR spectra exhibit large differences for normal and malignant tissues and subtle differences are seen between malignant and after-2-fractions of radiotherapy tissues. Spectral data were analyzed by principal component analysis (PCA) and it provided good discrimination of normal and malignant tissues. PCA of data of three tissues, normal, malignant, and 2-fractions after radiotherapy, gave two clusters corresponding to normal and malignant + after-2-fractions of radiotherapy tissues. A second step of PCA was required to achieve discrimination between malignant and after-2-fractions of radiotherapy tissues. Hence, this study not only further supports the use of formalin-fixed tissues in optical histopathology, especially from Raman spectroscopy point of view, it also indicates feasibility of discriminating tissues with minute biochemical differences such as malignant and after-2-fractions of radiotherapy.

Cervix Uteri↗
PubMed2006

FTIR and Raman microspectroscopy of normal, benign, and malignant formalin-fixed ovarian tissues.

Ovarian cancer is the sixth most common cancer among women worldwide, and mortality rates from this cancer are higher than for other gynecological cancers. This is attributed to a lack of reliable screening methods and the inadequacy of treatment modalities for the advanced stages of the disease. FTIR and Raman spectroscopic studies of formalin-fixed normal, benign, and malignant ovarian tissues have been undertaken in order to investigate and attempt to understand the underlying biochemical changes associated with the disease, and to explore the feasibility of discriminating between these different tissue types. Raman spectra of normal tissues indicate the dominance of proteins and lower contents of DNA and lipids compared to malignant tissues. Among the pathological tissues studied, spectra from benign tissues seem to contain more proteins and less DNA and lipids compared to malignant tissue spectra. FTIR studies corroborate these findings. FTIR and Raman spectra of both normal and benign tissues showed more similarities than those of malignant tissues. Cluster analysis of first-derivative Raman spectra in the 700-1700 cm(-1) range gave two clear groups, one corresponding to malignant and the other to normal+benign tissues. At a lower heterogeneity level, the normal+benign cluster gave three nonoverlapping subclusters, one corresponding to normal and two for benign tissues. Cluster analysis of second-derivative FTIR spectra in the combined spectral regions of 1540-1680 and 1720-1780 cm(-1) resulted into two clear clusters corresponding to malignant and normal+benign tissues. The cluster corresponding to normal+benign tissues produced nonoverlapping subclusters for normal and benign tissues at a lower heterogeneity level. The findings of this study demonstrate the feasibility of Raman and FTIR microspectroscopic discrimination of formalin-fixed normal, benign, and malignant ovarian tissues.

Biomarkers, Tumor↗
PubMed2006

In-vitro analysis of normal and aneurismal human ascending aortic tissues using FT-IR microspectroscopy.

FTIR microspectroscopy has shown to be a proven tool in the investigation of many tissue types. We have used this spectroscopic approach to analyse structural differences between normal and aneurismal aortic tissues and also aortas from patients with congenital anomalies like aortic bicuspid valves. Spectral analysis showed important variations in amide I and II regions, related to changes in alpha-helix and beta-sheet secondary structure of proteins that seem to be correlated to structural modifications of collagen and elastin. These proteins are the major constituents of the aortic wall associated to smooth muscular cells. The amide regions have thus been identified as a marker of structural modifications related to these proteins whose modifications can be associated to a given aortic pathological situation. Both univariate (total absorbance image and band ratio) and multivariate (principal components analysis) analyses of the spectral information contained in the infrared images have been performed. Differences between tissues have been identified by these two approaches and allowed to separate each group of aortic tissues. However, with univariate band ratio analysis, the pathological group was found to be composed of samples from aneurismal aortas associated or not with an aortic bicuspid valve. In contrast, PCA was able to separate these two types of aortic pathologies. For other groups, PCA and band ratio analysis can differentiate between normal, aneurismal, and none dilated aortas from patients with a bicuspid aortic valve.

Amides↗
PubMed2006

[Nano-biocaptures for research and diagnostics in inflammation diseases and cancer].

As part of the ongoing search for ways to decrease the mortality of different pathological conditions related to cancer and inflammatory diseases, nanotechnologies currently under evaluation offer potentially attractive tools for innovative methodologies for early diagnosis, new bioimaging techniques and therapeutic strategies. Nano-tools can be employed for various functions, such as the detection of lesions at very early stages of disease development, extremely precise anatomical localization, or evaluation of the efficacy of medications specifically targeted against cells and pathological tissues. We have synthesized homogeneous CdSe/ZnS (core/shell) highly fluorescent nanocrystals (NC) detectable as individual nanoparticules with a routine fluorescent microscope. These NC are at least 10-fold brighter than the best organic fluorophores and at least 1000-fold more stable against photobleaching than AlexaFluor, for example. When conjugated with proteins, DNA or with drugs, NCs may be excited with the light of any wavelength from UV through visible spectral region providing a range of fluorescence colors depending on their diameter. These properties provide excellent perspectives for high through-put multiplexing and long-term tracking of labeled precursors for days or even weeks. We present here NC applications for ultrasensitive detection of p-glycoprotein, cytokeratins, LCA, Ki67, etc. both on the cellular level and in pathological human surgical specimens.

Cells, Cultured↗
PubMed2006

[Immunohistochemistry in ophthalmic pathology: applications and limitations].

We evaluate the applications of immunohistochemistry (IHC) in ophthalmic cytology and pathology. The principles of the techniques used in IHC are described. Recent improvements are highlighted, such as the polymeric labeling two-step method, tyramine signal amplification, rabbit monoclonal antibodies, and labeled nanocrystals. The results of the immunohistochemical methods are collected in bacterial and viral diseases and in tumors of the eye and its adnexa, the pathology of which varies greatly. The results in lymphomas, melanomas, and palpebral tumors were more details for practical reasons. There are widespread applications of IHC in ophthalmic pathology, extending from viral ocular and general diseases to the diagnosis of tumors. In some conditions, this technique needs to be associated with molecular biology investigations. Automation helps establish standard protocols, but IHC is a multistep diagnostic method requiring proper selection, fixation, processing, and staining procedures. From a general standpoint, good communication between pathologists and ophthalmologists is the best guarantee of satisfying results.

Eye Neoplasms↗
PubMed2006

[Ocular melanoma: immunohistochemical evaluation of the potentially predictive markers of prognosis. Preliminary results].

PURPOSE: To study the characteristics of certain biological parameters, many of which have been recently discovered, to assess their possible contribution to the prognosis of ocular melanoma. MATERIAL: and methods: 25 patients with ocular and orbital melanoma treated at the Reims Regional Hospital since 1993 were included in the retrospective study. The surgical specimens were put in formalin 10%, then in paraffin. Five proteins were analyzed retrospectively: topoisomerase I, topoisomerase IIalpha, ICBP90, Ki67, and P53 on 200 cells per case. RESULTS: Of the 25 tumors from 14 men and 11 women, 15 were iris and ciliary body melanomas and ten choroidal melanomas. Histopathologic analysis showed 12 spindle-cell-type melanomas, seven epithelioid-cell-type melanomas and six mixed-cell-type melanomas. The immunohistochemical study found a significant difference in distribution between the cellular types for the topoisomerase IIalpha and Ki67 antibodies. Eight patients had metastasis, six of whom died. The metastasis came from three mixed-cell-type melanomas, three epithelioid-cell-type melanomas, and two spindle-cell-type melanomas. On the other hand, six cases of sclera infiltration were discovered among these eight patients. CONCLUSION: Several prognostic factors seem to be involved in the progression of melanoma: sclera infiltration seems to be essential in our study. Its rate seems to increase with the tumor size and in epithelioid-cell-type melanomas. The correlation between the different immunomarkers and the appearance of metastasis has not yet been verified.

Adult↗
PubMed2005

Evaluation of the suitability of ex vivo handled ovarian tissues for optical diagnosis by Raman microspectroscopy.

A pilot Raman microspectroscopy study of formalin-fixed, paraffin-embedded, and deparaffinized sections from the same ovarian normal and malignant tissues was carried out. This approach was considered in order to evaluate the suitability of these ex vivo tissue handling procedures in discrimination as well as biochemical characterization. The spectra of formalin-fixed normal and malignant tissues exhibited no contamination due to formalin, which is indicated by the absence of strong formalin peaks; spectral features also show significant differences for normal and malignant tissues. The differences between spectral profiles of deparaffinized normal and malignant tissues are subtle and spectra show few residual sharp peaks of paraffin. Complete dominance of paraffin swamping signals from tissues was observed in the spectra of paraffin-embedded tissues. Principal components analysis (PCA), which was employed for discrimination of tissue type, provided good discrimination for formalin-fixed and paraffin-embedded tissue spectra. PCA of deparaffinized tissues resulted in a poor classification with significant overlap among the clusters. Thus, this study indicates that formalin fixation is the most suitable among the three procedures employed in the study. Significant differences between spectral profiles of normal and malignant formalin-fixed tissues can not only be exploited for discrimination but can also provide information on biochemical characteristics of the tissues. Deparaffinized tissues provide poor discrimination and information on tissue biochemistry is lost. Paraffin-embedded tissues may provide good discrimination, but predominance of paraffin in the spectra could jeopardize biochemical characterization. Prospectively, as a result of the better availability of paraffin-embedded tissues and problems associated with frozen sectioning of formalin-fixed tissues, the results of this study using paraffin-embedded tissues are very encouraging.

Biochemistry↗
PubMed2004

[Pindborg tumor: a poorly differentiated form without calcification].

BACKGROUND: Pindborg tumor is a rare benign epithelial calcified odontogenic tumor. Radiological diagnosis is generally suspected because of the presence of calcifications. CASE REPORT: A 61-year-old man presented a polymorphous Pindborg tumor of the anterior maxillary. The diagnosis was hindered due to the nonspecific radiographic image and the lack of calcification. Pathology provided the positive diagnosis of poorly-differentiated young odontogenic epithelial tumor. DISCUSSION: Pindborg tumor is a rare lesions usually found in the posterior mandibular bone. Calcification is a characteristic feature. There are two historical forms, a squamous form with very favorable outcome and a clear-cell form with less favorable prognosis.

Diagnosis, Differential↗
PubMed2004

Micro-Raman spectroscopy for optical pathology of oral squamous cell carcinoma.

Micro-Raman spectra of formalin-fixed oral squamous normal and carcinoma tissues, stored at room temperature for 2 months, have been recorded. Spectra were recorded both in the epithelial and subepithelial regions of the tissues. No noticeable spectral contamination due to formalin was observed. Very significant differences between spectra of normal epithelial and malignant epithelial samples were found. No such differences in spectra of subepithelial malignant and subepithelial normal samples could be observed. This study shows that spectra from the epithelial region changes drastically because of malignancy-induced biochemical changes in this region. Major differences between normal and malignant spectra seem to arise from the protein composition, conformational/structural changes, and possible increase in protein content in malignant epithelia. The differences between normal epithelial and subepithelial spectra, as expected, arise mainly from the collagen in subepithelial tissue. Principal component analysis of the combined sets of spectra-epithelial and subepithelial, normal and malignant- showed that very good discrimination can be achieved by Raman microspectroscopy. This study thus validates the suitability of formalin-fixed tissues for optical pathology in oral malignancy.

Biomarkers, Tumor↗
PubMed2003

Lichen sclerosus is frequently present in penile squamous cell carcinomas but is not always associated with oncogenic human papillomavirus.

BACKGROUND: Penile squamous cell carcinoma (SCC) may occur on pre-existing lesions of lichen sclerosus (LS). However, the prevalence of histological changes of LS in penile SCC is not well established. Moreover, mucosal oncogenic human papillomaviruses (HPVs) are sometimes detected in penile SCC, but have not been systematically sought in LS-associated penile SCC. OBJECTIVES: To establish the prevalence of LS histological changes and of mucosal oncogenic HPV in a series of patients with penile SCC. METHODS: Consecutive cases of histologically proven penile SCC from a single university hospital over a 14-year period were retrospectively selected and reviewed. Histological signs of LS were systematically sought. HPV was detected by polymerase chain reaction (PCR) amplification of DNA from paraffin-embedded skin samples using general primers GP5+/GP6+ (allowing detection of mucosal HPV) and oncogenic type 16-, 18-, 31- and 33-specific primers. RESULTS: Eighteen cases of penile SCC were found. The mean +/- SD age of patients at diagnosis was 67.3 (14.5 years). In eight of 18 (44%) cases, SCC was associated with histological features of LS. Seventeen skin biopsy specimens of SCC (nine without and eight with LS histology) were subjected to PCR amplification for HPV. Mucosal HPV was detected in six of them (35%). Five of nine SCCs without histological features of LS were positive for mucosal HPV: three with HPV type 16 and two with only general primers. In contrast, all eight SCCs associated with LS were negative for oncogenic HPV types, although one was positive with general primers. CONCLUSIONS: Penile SCC seems to be frequently associated with LS histological changes. As with vulval SCC, we found that non-LS-associated penile SCC tended to be frequently associated with oncogenic HPV infection, whereas LS-associated penile SCC was not. Larger series are needed to confirm this association.

Adult↗
PubMed2003

[Pathology in the diagnosis and treatment of palpebral tumors].

UNLABELLED: The authors stress the role and place of pathology in the diagnosis and treatment of eyelid tumors. After a brief report on the main histological characteristics of eyelid tumors and their classification, the pathological methods are described, with particular attention paid to the technical aspects of frozen sections in palpebral surgery. AIM: This study reports the main pathological techniques available for use in eyelid tumor surgery. The advantages of frozen sections are reported from a retrospective study of basal-cell carcinomas of the eyelid. MATERIAL AND METHODS: All basal-cell carcinomas treated at the Reims Hospital from 1985 to 1999 were retrospectively studied. The pathological aspects are reported. Most of the tumors (155/193) were examined with frozen sections. Recurrences are considered. CONCLUSION: Pathology in eyelid tumor surgery must be taken into consideration. Frozen section examination may eliminate recurrences and limit healthy tissue taken at resection. This method is a very useful tool in this type of surgery. The benefits of the classic Mohs technique can be completed by a technique that is more precisely adapted to the control of the lateral limits of the excision in reconstructions which are often complex.

Adenocarcinoma, Sebaceous↗
PubMed2002

[Factors of recurrence of basal cell carcinomas of the eyelid].

UNLABELLED: Basal cell carcinomas of the eyelids can recur, although these recurrences are uncommon. In this retrospective study, all basal cell carcinomas treated at Reims Regional Hospital since 1985 were studied to determine the frequency of recurrence and the factors for recurrence. MATERIAL: and methods: All basal cell carcinomas treated at Reims Regional Hospital since 1985 were studied. A total of more than 200 patients had been operated on for basal cell carcinoma during this period. Those with orbital extension or a location on 2 eyelids were excluded. Epidemiological factors such as sex, age, tumor location, tumor size, and treatment were noted. Recurrences were uncommon, presenting in ten patients. These recurrences were studied in relation to the existing epidemiological data and the treatment provided, particularly the histological results. DISCUSSION: Basal cell carcinomas located on only 1 eyelid or 1 canthus can usually be treated with one surgical intervention. Extemporaneous histological study can preclude a local recurrence in most cases, but in some cases the condition may recur some years later. Factors favoring recurrence are difficult to determine. CONCLUSION: The authors report the number of recurrences after surgical treatment of basal cell carcinomas of the eyelids. The recurrences are relatively uncommon when the treatment has been done with extemporaneous histological examination of the resected edges. These recurrences arise particularly in relatively young patients with no other obvious risk factor.

Basal Cell Carcinoma↗
PubMed2002

[Malignant fibrous histiocytoma of the eyelid].

Fibrous histiocytomas, mostly benign, have often been reported in the orbit, but only four lesions have been described on the eyelids, with only one malignant. The authors present a case of malignant fibrous histiocytoma of the eyelid in a 76-year-old woman with a difficult histological diagnosis. Characteristics of this pathology are explained from data in the literature.

Aged↗
PubMed2001

[Laparoscopic diagnosis of stenosing eosinophilic jejuno-ileitis].

INTRODUCTION: Eosinophilic gastroenteritis of unknown origin could be isolated or integrated in idiopathic hypereosinophilic syndrome. Clinical expression is variable since the lesion may affect any area of the gastrointestinal tract and any layer of the wall. EXEGESIS: A 25-year-old male patient had digestive symptoms such as peritoneal, obstructive and diarrheal signs, associated with blood eosinophilia, giving evidence for eosinophilic jejuno-ileitis. Computer tomography revealed an extensive obstruction of the jejuno-ileum and thickening of the intestinal wall. The diagnosis was obtained using laparoscopy and controlled wedge biopsy, which showed a predominantly external infiltration of the intestinal wall by eosinophils. The disease evolution was favorable with corticosteroid therapy. CONCLUSION: Worrying and persistent digestive symptomatology, associated with blood eosinophilia, particularly when intestinal wall infiltration is revealed by computer tomography, should lead one to perform a laparoscopy to guide a surgical biopsy of the intestinal wall.

Adrenal Cortex Hormones↗
PubMed2001

Human DNA topoisomerase I inhibitory activities of synthetic polyamines: relation to DNA aggregation.

DNA aggregation by polyamines has acquired importance as a prerequisite for the cellular uptake of DNA for gene therapy. Intracellular polyamines are constitutive components of mammalian cells and their availability is critical for cell proliferation. Interference of polyamine biosynthesis by synthetic polyamines leads to cytotoxicity. Optimization of the polyamine structural parameters is necessary to control their DNA aggregation, cytotoxic or enzyme inhibitory activities. We designed two series of tetra- and hexamines and compared their human DNA topoisomerase I (top1) inhibitory effects with the DNA aggregation properties. We show that hexamines are more efficient inhibitors of DNA relaxation by top1 than tetramines and that they suppress the top1-mediated DNA cleavage while tetramines do not. The DNA aggregation abilities within two series of polyamines correlate with the length of their central methylene chain. By contrast, the top1 inhibition within two series does not show the same correlation but demonstrates a threshold inhibitory effect on going from the (CH(2))(12) to the (CH(2))(14) central chain. We show further that the structures of DNA aggregates formed by polyamines with the (CH(2))(10-12) or with the (CH(2))(14-16) chains are very different. The first are a fluid cholesteric-type phases, whereas the second are well-structured aggregates similar to columnar liquid crystals with high packing density of DNA duplexes. The structures of polyamines-induced DNA aggregates are proposed to be crucial for top1 catalysis. The structure-function correlation described here may serve as a guide for rational design of polyamines with desired DNA-aggregation or anti-top1 activities.

Base Sequence↗
PubMed2001

Detection and localization of a Ca2+-ATPase activity in Toxoplasma gondii.

Toxoplasma gondii, the agent causing toxoplasmosis, is an obligate intracellular protozoan parasite. A calcium signal appears to be essential for intracellular transduction during the active process of host cell invasion. We have looked for a Ca2+-transport ATPase in tachyzoites and found Ca2+-ATPase activity (11-22 nmol Pi liberated/mg protein/min) in the tachyzoite membrane fraction. This ATP-dependent activity was stimulated by Ca2+ and Mg2+ ions and by calmodulin, and was inhibited by pump inhibitors (sodium orthovanadate or thapsigargin). We used cytochemistry and X-ray microanalysis of cerium phosphate precipitates and immunolabelling to find the Ca2+, Mg2+-ATPase. It was located mainly in the membrane complex, the conoid, nucleus, secretory organelles (rhoptries, dense granules) and in vesicles with a high calcium concentration. Thus, Toxoplasma gondii possesses Ca2+-pump ATPase (Ca2+, Mg2+-ATPase) as do eukaryotic cells.

Adenosine Triphosphate↗
PubMed2001

[Hygiene, architecture and autopsy].

The 24(th) August 1998 decree related to technical prescriptions applicable to hospital mortuaries, to be enacted as of September 11(th) 2001, compels hospital administrations and involved personnel to consider architectural concepts of autopsy room. Nevertheless, the technical prescriptions of this decree seem to be inadequate because an autopsy room requires specific functional and technical organization such as adequate flooring, adapted air-conditioning system and plumbing and of course appropriate autopsy tables. Due to imminent enactement of accreditation procedures, it is likely that in the near future, autopsies will only be performed in centres combining scientific competence and sanitary requirements.

Autopsy↗