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L Guy

Publications and source records attributed to L Guy.

At least 19 recordsLinked to original sources
PubMed2006

One-month exposure to soy isoflavones did not induce the ability to produce equol in postmenopausal women.

OBJECTIVE: As more and more postmenopausal women are taking soy isoflavone supplementation for relieving menopausal symptoms, we investigated the impact of chronic exposure on their bioavailability, with focus on achievable plasma concentrations and potential stimulation of the capacity to produce equol. SUBJECTS: A total of 12 Caucasian postmenopausal women. INTERVENTION: Volunteers ingested 100 mg isoflavones/day (aglycone equivalents, in cereal bars and yoghurts) for 1 month. Plasma concentrations of metabolites at 2, 4, 6, 8, 10, 12 and 24 h postdose, as well as urinary excretion in fractions over 36 h were compared between days 1 and 30. RESULTS: Similar plasma kinetic curves were obtained at day 1 and day 30 for genistein and daidzein. Maximum plasma concentrations were 1.68+/-0.68 micromol/l on day 1 compared to 2.27+/-0.76 micromol/l on day 30 for daidzein (P=0.056), and 3.88+/-1.50 micromol/l on day 1 compared to 5.30+/-2.38 micromol/l on day 30 for genistein (P=0.091). Urinary excretion of daidzein and genistein did not differ significantly between days 1 and 30. Maximum plasma concentration of equol increased significantly from 0.31+/-0.27 to 0.99+/-0.51 micromol/l for equol-producer volunteers (P=0.046). However, the seven volunteers who were classified as non-equol producers on day 1 did not acquire the ability to produce equol after 1-month exposure. CONCLUSIONS: Chronic exposure to isoflavones in postmenopausal women resulted in plasma concentrations as high as 2.5-5 micromol/l of each isoflavone, but did not induce the ability to produce equol.

Administration, Oral↗
PubMed2005

Describing ancient horizontal gene transfers at the nucleotide and gene levels by comparative pathogenicity island genometrics.

MOTIVATION: Lateral gene transfer is a major mechanism contributing to bacterial genome dynamics and pathovar emergence via pathogenicity island (PAI) spreading. However, since few of these genomic exchanges are experimentally reproducible, it is difficult to establish evolutionary scenarios for the successive PAI transmissions between bacterial genera. Methods initially developed at the gene and/or nucleotide level for genomics, i.e. comparisons of concatenated sequences, ortholog frequency, gene order or dinucleotide usage, were combined and applied here to homologous PAIs: we call this approach comparative PAI genometrics. RESULTS: YAPI, a Yersinia PAI, and related islands were compared with measure evolutionary relationships between related modules. Through use of our genometric approach designed for tracking codon usage adaptation and gene phylogeny, an ancient inter-genus PAI transfer was oriented for the first time by characterizing the genomic environment in which the ancestral island emerged and its subsequent transfers to other bacterial genera.

Chromosome Mapping↗
PubMed2002

Vascular endothelial growth factor and signaling in the prostate: more than angiogenesis.

In cloning tyrosine kinase genes in dog prostate cells, a fragment of the vascular endothelial growth factor (VEGF) receptor 1 or Flt-1 was sequenced. To test for a functional protein, Flt-1 antibodies were used to probe immunoprecipitated tyrosine phosphorylated proteins. Western blotting revealed a major 170-180 kDa band and a few bands below 116 kDa in dog prostate and human prostatic carcinoma PC-3 cells, with higher levels in PC-3. Similar results were obtained with human placental membranes used as a source of Flt-1. That the major Flt-1 tyrosine phosphorylated protein was likely VEGF-R1 and part of VEGF signaling pathways was shown by enhanced level of only this protein when PC-3 cells were exposed to VEGF. Accordingly specific cell surface receptor complexes, displaced by VEGF but not EGF and compatible with Flt-1 in size, were revealed by chemical cross-linking after 125I-VEGF binding. Similarly to the prostatic neuroproduct, gastrin-releasing peptide/bombesin, VEGF directly triggered the tyrosine phosphorylation of focal adhesion kinase and stimulated PC-3 cell motility. The titration of prostate tissue sections with VEGF-A antibodies revealed a confined staining in chromogranin A and/or serotonin positive neuroendocrine (NE) cells, including in primary tumors and lymph node metastases. Given that NE differentiation is associated with advanced disease, that NE cells are a significant source of VEGF in prostatic tumors, and that VEGF directly act on prostate cancer cells in vitro, VEGF-A may be more than angiogenic in prostate cancer and hence favor progression by affecting tumor cells.

Amino Acid Sequence↗
PubMed2001

Tumor progression and survival in patients with T1G3 bladder tumors: multicentric retrospective study comparing 94 patients treated during 17 years.

OBJECTIVES: To compare tumor recurrence, progression, and patient survival in T1G3 bladder tumors treated with transurethral resection (TUR) alone, early cystectomy, or TUR with an adjuvant 6-week course of bacille Calmette-Guérin (BCG) and followed up for a minimum of 5 years. METHODS: Between 1979 and 1996, 94 patients with T1G3 bladder tumors (lamina propria invasion) were treated at nine different centers. The time to tumor recurrence, tumor stage and grade progression, number of delayed cystectomies, and patient survival were analyzed retrospectively in relation to the initial treatment. RESULTS: The mean follow-up was 62 months. Thirty patients were treated by TUR alone (32%), 50 patients by TUR plus BCG (53%), and 14 patients by primary cystectomy (15%). The recurrence, progression, and cystectomy rates were significantly different between patients treated by TUR alone and TUR plus BCG (Fisher's exact test, P = 0.0005, P = 0.02, and P = 0.005, respectively). The disease-free survival was also significantly different when comparing TUR plus BCG with TUR alone or primary cystectomy (Kaplan-Meier analysis, log-rank test, P = 0.02). CONCLUSIONS: Endoscopic resection plus BCG treatment of pT1G3 tumors allows an 80% rate of disease-free 5-year survival with bladder preservation. This conservative option has been widely accepted as first-line treatment, offering good cancer control with excellent quality of life. Very accurate surgical and pathologic evaluations before treatment and lifelong follow-up are obviously required.

Aged↗
PubMed2001

Minimally invasive extraperitoneal lymphadenectomy: clinical validation of an original technique.

PURPOSE: To validate an original technique described for pelvic node dissection. PATIENTS AND METHODS: A series of 192 patients were included in this study. The surgical technique we reported in 1987 is based on the use of a special retractor called the pelvioscope. The incision is the classical MacBurney incision on the right and its equivalent on the left. After the division of the muscles, the peritoneum is mobilized medially, and the pelvioscope is introduced. The node resection is then performed with classical surgical instruments. RESULTS: In total; 151 bilateral, 20 unilateral right, and 21 unilateral left node dissections have been performed. In one case, dissection was not possible on both sides, and in two cases, the dissection was not complete on one side (patients previously operated on). The average intraoperative time was 69 minutes for a unilateral procedure and 103 minutes for a bilateral procedure. The mean number of pelvic lymph nodes removed was 5.6 on each side. The overall rate of complications was 7.3%. CONCLUSION: The effectiveness of this minimally invasive surgery is clear, and the morbidity is low.

Adult↗
PubMed2000

[Kidney cancers with supra-diaphragmatic invasion. Surgical treatment using extracorporal circulation with heart arrest].

STUDY AIM: The study aim was to report results of nephrectomy with resection of cavo atrial thrombus in 6 patients with a renal carcinoma and supra-diaphragmatic vena cava extension and to discuss limits of the surgical indications. PATIENTS AND METHOD: Six patients, five adults (mean age: 57 +/- 10 years) and a four-year old girl, were operated on for a renal cell carcinoma with supra-diaphragmatic vena cava extension. The venous extension was detected in all cases by abdominal ultrasonography. The superior extent of the thrombus was effectively visualized by CT scan in three cases, and by ultrasonography and magnetic resonance imaging in all cases. All the patients were operated on, using cardio-pulmonary bypass, without circulatory arrest, four in normothermia, two in moderate hypothermia at 28 degrees C. RESULTS: Hospital mortality was 0%. Average intensive care unit stay was 3.8 days. During the following period, all the patients developed metastatic disease. Mean survival rate of the five adult patients who had loco-regional invasion was 9.4 months (range: 6 to 19). The young girl underwent a wedge excision of two pulmonary metastases one year later and was still alive 7 years later. CONCLUSIONS: With cardio-pulmonary bypass, surgical resection of cavo-atrial thrombi may be performed with a low mortality and morbidity rate but late results were disappointing. Surgery should be limited to patients without loco-regional invasion or distant metastatic disease, and therefore accurate preoperative staging is mandatory.

Adult↗
PubMed2000

[Nutrition and prostatic cancer].

Due to the major geographical variations affecting its clinical incidence, prostate cancer appears to be influenced by environmental factors, which may either promote or inhibit the development of this tumour. Diet appears to play a considerable role among these environmental factors. There are epidemiological and experimental arguments in favour of the role of diet in the development of prostatic cancer. Certain foods, such as fats, phenolic compound and other micronutrients such as vitamins or selenium have been reported to have an action on the natural history of prostate cancer. The authors present a review of the literature analysing the various potential actions of various foods.

Diet↗
PubMed1999

Searching for an intrinsic neuroendocrine cell in the kidney. An immunohistochemical study of the fetal, infantile and adult kidney.

The pathogenesis of primary renal carcinoid tumor is unknown. One hypothesis has implied derivation from a yet unrecognized intrinsic neuroendocrine cell in the renal parenchyma/hilum either as a minute endocrineparacrine constituent or resulting from entrapped/misplaced progenitor cells of the so-called dispersed neuroendocrine system during organogenesis. Immunohistochemical staining for chromogranin and serotonin was systematically performed on a whole-mount and geographically mapped normal adult kidney, kidneys from 15 fetuses (age range: 15 to 38 weeks), and renal specimens from 18 infants/children (age range: 7 days to 123 months). Minute paraganglion nests (composed of chromogranin positive/serotonin negative chief cells and S-100 protein positive dendritic cells) were incidentally detected within the renal hilum primitive stroma (unilaterally) of two fetuses at 22 and 26 weeks. Sequestration and persistence of such paraganglion nests during renal growth and maturation would offer a basis for the rare occurrence of extra-adrenal paraganglioma involving the renal hilum/pedicle. Otherwise, no neuroendocrine cell was detected within the renal parenchyma or hilum, therefore not validating/sustaining the aforementioned hypothesis in the pathogenesis of renal carcinoid tumor.

Carcinoid Tumor↗
PubMed1999

[Human ejaculation: physiology, surgical conservation of ejaculation].

OBJECTIVE: The most widely accepted theory to explain ejaculation consists of two phases: 1) A phase of accumulation of the various constituents of semen inside the prostatic urethra. 2) A phase of expulsion with opening of the striated sphincter, while the smooth sphincter of the bladder neck remains closed. The objective of this study was therefore to confirm or invalidate this hypothesis. MATERIAL AND METHODS: Eight volunteers were studied by continuous transrectal ultrasonography allowing dynamic analysis of ejaculation. Sixteen patients presenting with a bladder neck obstruction syndrome were treated by a technique preserving the last centimetre of supramontanal urethra. RESULTS: In the eight healthy subjects, we constantly and successively observed: filling of the ejaculatory ducts. prostatic contractions. Expulsion of the contents of the seminal vesicles into the inframontanal urethra, without prior ballooning of the prostatic urethra. In the 16 patients treated for bladder neck obstruction, we did not observe any case of retrograde ejaculation.

Adult↗
PubMed1999

[Traumatic dislocation of the testis. Report of three cases].

The authors report three cases of traumatic dislocation of the testis. Each case concerned a young patient, victim of a motorbike accident with direct trauma to the perineum and scrotum on the reservoir. Preoperative radiological assessment consisted of ultrasound, computed tomography, or even magnetic resonance imaging, depending on the case. Surgical exploration revealed 3 traumatic dislocations of the testis, including one with associated torsion of the spermatic cord. One case also presented fracture of the contralateral testis, which was not dislocated. Each case was repaired by repositioning of the testis in the scrotum. The fractured testis could not be preserved. A review of the literature confirmed the rarity of these traumatic lesions. Dislocations are usually inguinal, sometimes bilateral, and can be ectopic. Spermatic cord lesions may also be associated. The authors define the place of radiological assessment, which can guide the diagnosis and therapeutic strategy. Surgical exploration, allowing assessment of the lesions, is required in every case. Repositioning of the testis in the scrotum ensures cure when the testis is still viable.

Accidents, Traffic↗
PubMed1999

[Value of Führman's nuclear grade: comparison with other prognostic factors of renal epithelial tumors].

OBJECTIVE: To assess the prognostic value of Führman's nuclear grade and to compare it to various clinical and histological prognostic factors of renal carcinomas. PATIENTS AND METHOD: Single-centre retrospective study of 102 patients operated for renal tumours between January 1985 and December 1990 (mean follow-up: 8.2 years). Prognostic assessment was studied from survival curves. RESULTS: The prognostic factors most closely correlated with survival were, in decreasing order, metastatic invasion, nuclear grade, stage of local extension and lymph node invasion. A significant (p < 0.01) survival difference was only observed between Führman grade 2 and grade 3 tumours. This difference was accentuated (p < 0.001) when grade 1 and 2 tumours were compared to grade 3 and 4 tumours. Führman's nuclear grade is independent of the side affected, the tumour volume, its multifocal nature, microscopic venous invasion and metastatic invasion at the time of diagnosis. Führman's nuclear grade is correlated with invasion of fat, the presence of a contingent of eosinophilic cells, stage of local extension, lymph node invasion and the subsequent development of metastases. CONCLUSION: This study confirms the importance of Führman's nuclear grade among the various prognostic factors of renal carcinomas and quantifies its value with respect to other prognostic factors.

Adult↗
PubMed1998

Design and synthesis of hydrazinopeptides and their evaluation as human leukocyte elastase inhibitors.

The name hydrazinopeptide designates peptidic structures in which one of the native CONH links is replaced by a CONHNH (hydrazido) fragment. In this paper, we report the synthesis of such hydrazinohexapeptides (3-5) analogous to Z-Ala-Ala-Pro-Val-Ala-Ala-NHiPr (6), a substrate of human leukocyte elastase (HLE; EC 3.4.21.37), cleaved by this serine protease between the Val4 and Ala5 residues. In hydrazinopeptides 3-5, the Ala5, Val4, or Pro3 residue, respectively, of the model peptide, has been replaced by the corresponding alpha-L-hydrazino acid. In 3, the bond likely to be cleaved by HLE is the one involving the CONHNH link, while in 4 and 5, this link is normally shifted away by one or two amino acid units from the catalytic serine. On incubation with HLE, hydrazinopeptide 3 proved to be a substrate and was cleaved between Val4 and NHAla5, like peptide 6. In contrast, 4 and 5 proved to bind to HLE without being cleaved, featuring properties consistent with reversible competitive inhibition. General guidelines for the synthesis of hydrazinopeptides are also reported in this paper. These guidelines take into account the chemical specificity of hydrazino acids, while being fully compatible with the conventional peptide coupling techniques. The utilization of orthogonally bisprotected hydrazino acids 1 where the Nbeta and Nalpha atoms bear a Boc and a Bzl group, respectively, is recommended for the easy construction of such hydrazinopeptides.

Drug Design↗
PubMed1998

Renal carcinoid and horseshoe kidney: a frequent association of two rare entities--a case report and review of the literature.

We report the case of a primary renal carcinoid tumor associated with a horseshoe malformation in a 43-year-old man who presented with testicular pain. The tumor was centrally located and purely solid and had features ascribed to hindgut neuroendocrine neoplasia. The relative risk of developing a carcinoid tumor in a horseshoe kidney is estimated to be x82.

Adult↗
PubMed1998

Neuroendocrine cells of the verumontanum: a comparative immunohistochemical study.

OBJECTIVE: To define the distribution of neuroendocrine (NE) cells in the different compartments of the verumontanum (utricle, ejaculatory ducts, main prostatic ducts) in relation to other areas of the prostate. MATERIALS AND METHODS: A retrospective study was conducted of 30 radical prostatectomy specimens processed in toto as whole-mount sections. Among these cases, 15 patients had received a preoperative short course of total androgen blockade. The distribution and number of NE cells in the prostatic utricle and in normal areas of the prostate were analysed using chromogranin A (CgA) and serotonin immunohistochemistry; prostate-specific antigen (PSA) immunostaining was performed systematically on a consecutive section. Six cases of endometrioid carcinomas were also investigated using these methods. The vascularization of the verumontanum was assessed by factor VIII immunohistochemistry and examined in relation to vascular endothelial growth factor (VEGF) immunohistochemistry. RESULTS: There were significantly more NE cells in the prostatic utricle than in the main prostatic ducts of the verumontanum and the peripheral prostatic acini. In the ejaculatory ducts. there were NE cells only in the extreme distal portion. Cells immunoreactive for PSA were present at the level of the utricle and the extreme distal portion of the ejaculatory ducts. The distribution, number and shape of NE cells were unaltered by hormonal treatment. NE cells of the verumontanum were positive for VEGF expression. Factor VIII detected more vessels around the utricle and ejaculatory ducts. NE cells (positive for CgA and serotonin) were observed in three cases of endometrioid carcinoma. CONCLUSION: The high concentration of NE cells found in the prostatic utricle suggests a possible role for these cells in human fertility. Moreover, neuroendocrine differentiation in endometrioid (large duct) carcinoma, documented for the first time, supports the concept that this cancer type is a variant of a conventional adenocarcinoma.

Chromogranin A↗
PubMed1998

[Use of the Valtrac ring for digestive anastomoses in urology: apropos of 16 cases].

The Valtrac ring is a biofragmentable ring used for gastrointestinal anastomoses. Over a two-year period, 15 anastomoses in 16 patients (mean age: 60 years) were performed with the Valtrac ring: 10 ileal, 4 ileocolonic, and 1 jejunojejunal anastomoses. One anastomosis could not be performed because of an excessively narrow ileal lumen. The mean stay in the intensive care unit was 3 days: gastric aspiration was maintained for an average of 1 week, as return of gastrointestinal motility was long, with first flatus on the 6th day and the first stools on the 7th day. Complications consisted of 2 cases of gastrointestinal fistula (11th and 13th days) one of which was fatal, evisceration on the 7th day, a transient partial bowel obstruction and one bowel obstruction treated medically on the 27th day, due to pancreatitis. Our results are not identical to those reported in the literature. It is often difficult to insert the current form of the Valtrac ring into a healthy ileum, as the smallest ring is often too large. In contrast with gastrointestinal surgery, the anastomoses performed in urology involve a non-thickened, non-distended small intestine.

Adult↗