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Y Arce

Publications and source records attributed to Y Arce.

10 recordsLinked to original sources
PubMed2006

[Usefulness of the present renal cell carcinoma classifications].

The purpose of classifying neoplasias is to recognize groups with similar progress and prognosis and, if possible, receiving the same treatment. This is why those classifications are systematically being submitted to review and improvement through the new technologies. Differentiation of various entities in renal cancer has been comparatively fast, as the new genetic and molecular discoveries have confirmed the morphologic criteria of the different cell types, thus making it possible to open new therapeutic pathways. Using the current WHO classification we recognize subtypes with excellent prognosis (Multilocular cystic renal carcinoma, Type I renal papillary carcinoma, Tubular and fusocellular mucinous carcinoma), other very aggressive ones (Bellini's collecting duct carcinoma, Medullary carcinoma), and also that the sarcomatoid transformation, even in small areas, impacts the prognosis negatively. Childhood-characteristic renal carcinomas associated with chromosome translocations have been recognized (genetic fusion TFE3 or TFEB), as well as the family forms of renal carcinoma. Regarding the UICC (International Union Against Cancer) classification, there are a series of aspects under argument (size, venous invasion, microvascular invasion, invasion of the adipous tissue of the renal sinus) that shall be discussed too, since it is possible that some modifications of the TNM might occur in the near future.

Adenocarcinoma, Mucinous↗
PubMed2005

Intraoperative frozen section diagnosis in urological oncology.

The intraoperative frozen sections are indicated if the pathological findings change the surgical procedure. In urological oncology is not recommended, as a general attitude, in the tumor diagnosis/staging during the surgery. The assessment of the surgical margins is recommended in partial surgical resections but the literature discourages its systematic use in the radical surgical resections. The assessment of the lymph nodes is specially indicated in the penile cancer with intermediate or high risk and non-palpable nodes, and is debated its utility in non-palpable lymph nodes of cystectomies and prostatectomies.

Female↗
PubMed2005

Prognostic parameters other than Gleason score for the daily evaluation of prostate cancer in needle biopsy.

OBJECTIVE: To evaluate in prostate needle biopsies the usefulness and the efficacy of not time-consuming morphologic parameters in order to predict whether prostate cancer is organ-confined or it is not, that could contribute additional information to pre-surgical serum PSA and Gleason score, both of them parameters already accepted as clinically significant. METHODS: Three hundred and two consecutive patients were evaluated, of whom a diagnostic needle biopsy and the radical prostatectomy specimen with no pre-surgical hormone therapy were available. Bilateral or unilateral extension, number of positive cores, percentage of positive cores, intraprostatic perineural invasion (IPNI) and the presence of high-grade prostatic intraepithelial neoplasia (HGPIN) in any of the biopsy cores were evaluated in the needle biopsy. RESULTS: The median of cores is 6. The IPNI, the presence of bilateral tumour, and the percentage of positive cores, higher than 37.5% (ROC curve), show significant crude OR (4.0, 2.8, 6.9 respectively). The regression model discloses that only the percentage of positive cores shows a significant OR (5.8) adjusting for bilaterality, IPNI, HGPIN and age. CONCLUSIONS: The percentage of cores with cancer and the bilateral involvement are another two parameters predictive of cancer with extraprostatic extension. (p<0.0005 in both). IPNI has statistical significance too (p<0.002), but it is related to the tumour volume expressed through the two mentioned parameters.

Adult↗
PubMed2002

Intrapulmonary neutrophil apoptosis in a pig model of pneumonia.

BACKGROUND: Apoptosis and necrosis are two distinct cell death modalities. Polymorphonuclear leukocytes (PMNL) play an important role in pneumonia and little information is available on whether these cells are cleared by necrosis or apoptosis. We therefore compared the proportion of apoptotic PMNL in lung tissues with and without pneumonia. In addition, the association of PMNL apoptosis and mechanical ventilation (MV) was investigated. METHODS: Samples obtained from a pig model developed to tracheobronchial stenting were analysed. Pneumonia was induced with that model in 10 animals (white-Landrace piglets, Pittman-Moore or Göttingen minipigs). Animals were sacrificed when clinical parameters of pneumonia became evident and 17 lung samples could be analysed for histologic evidence of pneumonia, growth of micro-organisms, and the apoptotic index (proportion of apoptotic PMNL over all PMNL in a 400-power field). In addition, lung samples (n = 7) from two pigs without stent implantation on mechanically ventilated for more than 48 h were studied. RESULTS: A total of 9/17 samples (53%) showed histologic evidence of pneumonia, 11/17 (65%) had significant bacterial growth (> 10(3) cfu/g), and 7/17 (41%) fulfilled both criteria. The apoptotic index was not significantly different in samples with and without histologic evidence of pneumonia (pneumonia: 25.3 +/- 6.1% vs. No pneumonia: 25.2 +/- 11.9%; 95%CI: -9.7 - 9.5, p = 0.989) or in samples with and without significant bacterial growth (significant bacterial growth: 23.5+/-9.3% vs. No significant bacterial growth: 28.5+/-8.2%; 95%CI: -4.6 - 16.7; p = 0.284). However, the apoptotic index was higher in samples of pigs, mechanically ventilated for more than 48 h, compared to the stent group (MV: 36.9+/-10.7% vs. Stent: 25.2 +/- 9.0%; 95% CI: -20.5 - -2.9; p = 0.012). CONCLUSION: In an animal model, the proportion of apoptotic PMNL was not different in lung samples with and without histologic or bacterial pneumonia. However, MV for more than 48 h was associated with a higher proportion of apoptotic PMNL in lung tissue. This study may be helpful for the understanding of the evolution of lung tissue damage induced by bacterial pneumonia and MV.

Animals↗
PubMed1999

Expression of p27/Kip1 is down-regulated in human prostate carcinoma progression.

p27(Kip1) is a cyclin-dependent kinase inhibitor whose down-regulation has been observed in several tumour models, including breast, colorectal, and gastric carcinomas. The purpose of this study was to assess p27(Kip1) protein expression in normal and benign prostatic epithelia as well as the possible existence of abnormalities in prostate carcinoma progression. p27(Kip1) expression was immunohistochemically analysed in 51 normal tissue samples, 11 nodular hyperplasias (NH), 22 high-grade prostatic intraepithelial neoplasias (PIN), 56 localized prostate adenocarcinomas, and 19 metastases. Immunoblotting was performed in ten cases. Normal prostate epithelium and NH showed diffuse and intense p27(Kip1) nuclear expression in most cases. A significant p27(Kip1) down-regulation was observed in many carcinomas when compared with benign epithelium. Forty-seven cases (84 per cent) were low p27(Kip1) expressors (<50 per cent positive cells) and nine cases (16 per cent) were high p27(Kip1) expressors. p27(Kip1) down-regulation was also consistently seen in PIN. Fourteen out of 19 metastases (74 per cent) were low p27(Kip1) expressors. Six metastatic samples had their corresponding primary tumour analysed and three cases showed decreased expression in the metastasis. It is concluded that p27(Kip1) is constitutively expressed in normal and benign prostatic tissue. This expression is clearly down-regulated in neoplastic progression from the preinvasive lesions through invasive carcinoma and metastases and this therefore occurs in early stages of neoplastic transformation.

Adenocarcinoma↗
PubMed1999

VCAM-1 and ICAM-1 mediate leukocyte-endothelial cell adhesion in rat experimental colitis.

BACKGROUND & AIMS: The molecular mechanisms responsible for leukocyte recruitment in experimental colitis are poorly understood. The aims of this study were to measure expression of endothelial intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) and to determine their role in leukocyte recruitment in experimental colitis. METHODS: Rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis and control rats were studied 1, 7, or 21 days after treatment. ICAM-1 and VCAM-1 expressions were measured by the double radiolabeled antibody technique. Leukocyte-endothelial cell interactions were determined in colonic venules by fluorescence intravital microscopy. Therapeutic effects of treatment with anti-VCAM-1 antibodies were also assessed. RESULTS: Colonic endothelial ICAM-1 was constitutively expressed and did not increase in colitic animals. In contrast, constitutive expression of VCAM-1 was low but markedly increased (6-fold) 1 and 7 days after induction of colitis. Increased colonic expression of VCAM-1 paralleled macroscopic damage score, myeloperoxidase activity, and increased leukocyte adhesion in colonic venules. The latter was significantly decreased by immunoneutralization of ICAM-1 and completely abrogated by immunoneutralization of VCAM-1. Long-term administration of anti-VCAM-1 antibody resulted in significant attenuation of colitis. CONCLUSIONS: Induction of colitis in rats by TNBS is followed by up-regulation of endothelial VCAM-1. VCAM-1 and constitutive ICAM-1 are major determinants of leukocyte recruitment to the inflamed intestine.

Animals↗
PubMed1998

Effects of steroid treatment on activation of nuclear factor kappaB in patients with inflammatory bowel disease.

Nuclear factor kappB (NFkappaB) is a transcription factor that controls several genes important for immunity and inflammation. The aim of this study was to assess if activation of NFkappaB plays a role in the pathogenesis of inflammatory bowel disease (IBD), and whether steroid treatment affects NFkappaB activation. Activation of NFkappaB was analysed in colon biopsy samples of 13 patients with active IBD (8 Crohn's colitis, 5 ulcerative colitis) by electrophoretic mobility-shift assays, under basal conditions and 3 weeks after treatment with 0.75 mg kg(-1) day(-1) prednisolone. The presence of interleukin-8 mRNA in biopsies was assessed by RT-PCR. A specific NFkappaB band was present in all nuclear extracts from inflamed mucosa, whereas the band was barely detectable in uninflamed colonic mucosa. NFkappaB bands were super-shifted by antibodies against p50 subunit, whereas antibodies against p65, p52, c-Rel, or Rel B did not modify the mobility of the band. Increased interleukin-8 mRNA was detected at the same sites of NFkappaB activation. Steroid-induced healing of colonic inflammation was associated with disappearance of NFkappaB from nuclear extracts. These results support the notion that NFkappaB plays an important role in the pathogenesis of IBD, and that blockade of NFkappaB activation is one of the mechanisms by which steroids suppress the inflammatory cascade in IBD.

Adult↗
PubMed1996

[Xanthogranulomatous cholecystitis simulating gallbladder neoplasm: therapeutic implications].

Xanthogranulomatous cholecystitis (XGC) is an infrequent type of chronic cholecystitis whose histologic features, in some cases, show a macroscopic appearance which may lead to suspicion of a gallbladder neoplasm with the consequent contraindication of the laparoscopic approach. The incidence of XGC was reviewed in a prospective series of 514 cholecystectomies performed in the authors' department from January 1991 to January 1996. Fourteen cases (2.7%) of XGC were identified with a male/female ratio of 1/1.8 and a mean age of 71 +/- 9 years. The most frequent form of presentation observed was hepatic cholic (43%). Echography showed cholelithiasis in 13 patients (93%). In 3 cases (21%), clinical and echographic suspicion of neoplasm was established, two being in the gallbladder, thus contraindicating the laparoscopic approach. A third patient underwent surgery for suspicion of a colon neoplasm. Xanthogranulomatous cholecystitis presents a macroscopic appearance which may be interpreted as a gallbladder neoplasm in up to 25% of the cases thus leading to treatment with laparoscopy.

Aged↗
PubMedDate not supplied

Histopathology of ventilator-associated pneumonia (VAP) and its clinical implications.

Ventilator-associated pneumonia (VAP) is a diffuse polymicrobial and dynamic process, with heterogeneous distribution of lesions, showing different degrees of histological evolution predominating in the dependent lung zones, in which microbiology and histology can be dissociated. This might explain why blind endobronchial techniques to collect respiratory secretions have similar accuracy compared to visually guided samples, explaining the difficulties in validating any methods for its diagnosis. In the clinical setting the association of acute lung injury (ALI) and pneumonia is controversial. However, it is rare to detect diffuse alveolar damage (DAD) in absence of histological signs of pneumonia, probably evidencing that ALI favors the development of pneumonia. Histopathologically, it is difficult to distinguish initial and resolution phases of DAD from pneumonia and vice versa. On the other hand, there is a clear relationship between antimicrobial treatment and the decreased lung bacterial burden which strengthens the importance of distal airway sampling before starting antibiotic therapy.

Animals↗