175 research outputs found
Possible sources of iron for lipid peroxidation
Possible sources of iron for lipid peroxidation are described and discussed. In particular. evidence is presented that microsomes contain ferric nonheme iron which may participate in formation of lipid oxidants. provided reductants are available to favor its mobilization from membrane binding sites. Aging-and tumor-associated changes of this microsomal pool of nonheme iron are also described and discussed from biochemical and biomedical viewpoints. © 1991 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted
Surgical treatment of achalasia: A retrospective comparative study
A retrospective study carried out on 74 patients among 101 consecutive cases of achalasia of the esophagus operated from 1967 to 1989 is reported. On 21 patients observed between 1967 and 1975, a standard transabdominal Heller cardiomyotomy was performed (group A). From 1976 to 1989, the treatment of choice was a Heller myotomy associated with a modified Dor's fundoplication. In 80 consecutive cases (group B) the extension of myotomy was regulated by intraoperative monitoring of lower esophageal sphincter pressure. A 5-year follow-up with questionnaires, physical examination, and barium swallows was carried out on 16 patients in group A and on 58 patients in group B. In 75.6% of the cases (56 patients) follow-up examinations included esophageal manometry and 24-hour esophageal pH monitoring. Recurrence of dysphagia was recognized in 3 cases in group A (18.7%) and in 2 cases in group B (3.4%) (P=0.053); postoperative gastroesophageal reflux, measured as a percentage of total reflux time, showed a significantly lower mean value in group B than in group A (1.8% vs. 4.1%. P<0.01). This study suggests that an anti-reflux procedure lowers post-operative gastroesophageal reflux after Heller myotomy. Due to the low incidence of postoperative reflux and the negligible recurrence of dysphagia, Heller myotomy associated with a modified Dor's fundoplication may represent the surgical treatment of choice for achalasia of the esophagus. © 1993 Springer-Verlag
Increasing complexity of farnesyltransferase inhibitors activity: role in chromosome instability.
Oncogenic Ras proteins have been seen as an important target for novel anticancer drugs. Due to the functional role of Ras farnesylation, fanesyltransferase (FTase) inhibition was thought to be a strategy for interfering with Ras-dependent transformation. When farnesylation is blocked, the function of Ras protein is severely impaired because of the inability of the nonfarnesylated protein to anchor to the membrane. Although it has been clearly demonstrated that FTase inhibitors (FTIs) inhibit Ras farnesylation, it is uncertain whether the antiproliferative effects of these compounds result exclusively from the effects on Ras. Moreover, no consensus has been reached as to the relevant targets(s) of FTIs that can explain their mosaic pharmacology. In searching for downstream targets for FTIs effects, CENP-E and CENP-F/mitosin were identified. Different studies showed that the inhibition of farnesylation interferes with CENP-E-microtubule association. In the presence of FTIs, chromosome alignment to the metaphase plate is delayed, suggesting that farnesylated proteins are involved in a step critical to bipolar spindle formation and chromosome alignment. An important question is whether these biological effects might contribute to the chemotherapeutic effects of the FTIs. However, FTIs, triggering the spindle checkpoint, might elevate the rate of cellular missegregation to levels that are incompatible with cell viability, as well as have a reduced (but still significant?) effect on checkpoint-proficient normal cells. As an example, RPR-115135 induced micronuclei (MN) increase in cancer cells displaying high chromosome instability (CIN) levels, whereas in normal cells it is devoid of activity. Cancer cells showing high CIN level might represent an ideal target for the activity of some FTIs
The prognostic role of anatomo-pathological factors in colorectal cancer: an univariate analysis
An univariate analysis of pathologic data of 987 patients with primary colorectal carcinoma treated over a period of 22 years was performed. Six variables such as tumor site, histologic type, depth of invasion, nodal involvement, distant metastases, histologic grade and tumor stage were tested for their prognostic value. 5-year survival rate was investigated. Patients with tumors in the left colon and rectum have shown a better prognosis than patients with tumors in the right colon (53-51% vs. 38% p = 0.0007). As regard histologic type non significant differences between mucinous and non-mucinous carcinoma was observed (44% vs 48% respectively p = 0.4). The depth of tumor invasion was an important prognostic factor; according to tumor infiltration patients can be divided in four groups (T1, T2, T3, T4) with 5-year survival rates of 80%, 74%, 39% and 16% respectively (p = 0.0000). Highly significant decrements in survival occurred when lymph node metastases were demonstrable (20% vs. 67% p = 0.0000). Prognosis was still strongly related to histologic grade, with significant difference in survival rates between G1 and G2-G3 tumors (71% vs. 48%-42% p = 0.0000). Finally prognosis was closely related to the stage of spread at the time of diagnosis
Lymphangiography in recurrent spontaneous chylothorax
We have recently been involved in an interesting discussion related to the pre-operative assessment of spontaneous (SC) and post-traumatic chylothorax (PTC) on the journal’s pages. We herein report an image (Fig. 1 ) which clearly underlines the usefulness of pre-operative lymphangiography in recurrent SC and further supports our thesis as discussed
Unsuspected primary pulmonary meningioma
Primary pulmonary meningioma is an uncommon, usually benign, soft tissue tumour which has rarely been reported. We report an additional case of primary pulmonary meningioma occurring in an asymptomatic 56-year-old man whose diagnosis was only established after resection. The features of this lesion together with a review of the previous literature are described. © 2002 Elsevier Science B.V. All rights reserved
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