Total anorectal reconstruction with the artificial bowel sphincter: report of eight cases. A quality-of-life assessment

PURPOSE

The artificial bowel sphincter has been proposed to treat patients with fecal incontinence. The good results achieved with this procedure encouraged us to use this device for reconversion of patients who previously underwent an abdominoperineal resection.

METHODS

Between 1999 and 2001, we selected eight patients for the total anorectal reconstruction, five for a synchronous reconstruction, and three cases for a delayed procedure. One patient was male and seven were female. The mean age was 52.6 years. All the patients underwent a postoperative manometry and defecography. Continence and quality of life scores were also evaluated in the follow-up.

RESULTS

The follow-up length ranged from 6 to 28 months. Manometry assessed a basal pressure with the ABS cuff inflated between 58 and 62.2 mmHg. All but one patient achieved a good grade of continence with a Wexner score range between 3 and 9. A certain degree of impaired evacuation occurred in three patients, but with adequate training this improved and did not affect patient's satisfaction. The administered questionnaires demonstrated a significant improvement in quality of life scores for stoma patients and an elevated quality of life in patients synchronously treated with artificial bowel sphincter implant.

CONCLUSION

The artificial bowel sphincter is a good option for reconstruction of patients previously treated with an abdominoperineal resection. The procedure is feasible and safe, without serious postoperative complications. The quality of life is improved when the procedure is performed in stabilized stoma patients and is acceptable for motivated patients synchronously implanted. As compared with electrostimulated graciloplasty, the artificial bowel sphincter technique seems to be easier to perform and more acceptable for the patients, although the cost of the device is still high.

Factors influencing hospital infection control policies in Italian hospitals

A study was undertaken to determine the resources available in Italian hospitals for the control of nosocomial infections and the factors favouring a successful approach. During January-May 2000 a questionnaire about infection control was sent to the hospital health director of all Italian National Health System hospitals treating acute patients and with more than 3500 admissions in 1999. An active programme was defined as a hospital infection control committee (HICC) meeting at least four times in 1999, the presence of a doctor with infection control responsibilities, a nurse employed in infection control and at least one surveillance activity and one infection control guideline issued or updated in the past two years. There was a response rate of 87.5% (463/529). Almost fifteen percent (69/463) of hospitals had an active programme for Infection Control and 76.2% (353/463) had a HICC. Seventy-one percent (330/463) of the hospitals had a hospital infection control physician and 53% (250/463) had infection control nurses. Fifty-two percent (242/463) reported at least one surveillance activity and 70.8% (328/463) had issued or updated at least one guidance document in the last two years. The presence of regional policies [odds ratio (OR) 8.7], operative groups (OR 4.2), at least one full-time nurse (OR 4.6) and a hospital annual plan which specified infection control (OR 2.1) were statistically associated with an active programme in the multivariate analysis.

Treatment strategies for postinfarction left ventricular free wall rupture: stabilization with peri-operative IABP and off-pump repair

BACKGROUND

Perioperative management of post-infarction left ventricular free wall rupture (LVFWR) is not clearly standardized and surgical repair is the only therapeutic option. Role of off-pump surgery and stabilization with perioperative intraaortic balloon pumping (IABP) were here analysed.

METHODS

Seven patients underwent surgery for LVFWR between 1990 and 2002. Clinical picture included electromechanical dissociation (3 patients) and sudden hypotension (4 patients). Except in one patient who was reanimated through femoro-femoral cardiopulmonary bypass, off-pump repair through on-lay patching technique was always performed. IABP was employed in the immediate postoperative period in five cases.

RESULTS

A satisfactory hemodynamic state was restored in all cases and there were no reoperations for bleeding or rerupture. Hospital survival was 100%. One patient underwent successful surgical myocardial revascularization two months after LVFWR. Two patients died at follow-up. The survivors present with good NYHA and CCS functional classes.

CONCLUSIONS

When the anatomy of the LVFWR is favourable, off-pump external patching repair proves a good choice. Postoperative IABP provides satisfactory hemodynamic support.

Should we continue to study high-dose chemotherapy in metastatic breast cancer patients? A critical review of the published data

Data from eight randomised trials on high-dose chemotherapy (HDC) for metastatic breast cancer (MBC) have been published, but only seven studies are evaluable after the Bezwoda trial was discredited. Moreover, overall survival (OS) has been evaluated in only four out of seven studies since three had a crossover design. OS was similar for the HDC and standard-dose chemotherapy (SDC) group in the four evaluable trials, while disease-free survival (DFS) was improved in the HDC group in six of the seven trials. The delay in relapse for patients with metastatic disease represents an important clinical outcome; furthermore, since none of the reported studies randomised more than 220 patients, their statistical power may have been too limited to detect meaningful survival differences. Finally, preliminary experiences have shown that HDC seems to be the ideal platform upon which to build novel therapies. In conclusion, HDC remains an important field of clinical research for breast cancer patients with stage IV disease and, from the studies reported in this article, there is some evidence for offering this therapeutic modality to selected patients who are interested in a medically aggressive approach.

Is diabetes mellitus a risk factor for HCV infection?

The aim of this study was to investigate whether or not the diabetes mellitus may be considered a risk factor for the HCV infection. The HCV seroprevalence was evaluated in 254 diabetic subjects, whose anamnestic data and risk factors are known, in comparison to 223 first-time blood donors, carefully age- and gender-matched. The statistical analysis showed that the studied groups belonged to the same population (Mann-Whitney U test) and that there were no significant differences between cases and controls as regards HCV prevalence (Yates corrected chi 2 test). The obtained data underline the importance of the control group selection, especially in the studies considering age-related pathologies. The authors disprove type 2 diabetes as a risk factor for the HCV infection and consider that this is a valid hypothesis only when the hepatitis C was unknown and not adequate prevention was used.

Total anorectal reconstruction with an artificial bowel sphincter: Report of five cases with a minimum follow-up of 6 months

BACKGROUND: The artificial bowel sphincter (Acticon ABS - American Medical Systems, Minneapolis, MN, USA) has been proposed as a treatment for patients with faecal incontinence. The good results achieved with this procedure encouraged us to utilize this device for reconstruction of patients who previously underwent an abdominoperineal resection (APR). METHOD: Between 1999 and 2000 we implanted the ABS in five patients undergoing an APR. One patient was male and four female, the mean age was 51.3 years. Three patients had been operated on for rectal cancer, one for rectal agenesia and one for a giant benign tumour of the pelvis. RESULTS: The length of follow up ranged from 6 to 22 months. Manometry assessed a basal pressure with the ABS cuff inflated between 58 and 62.2 mmHg. All but one achieved a good grade of continence with a Wexner score range between 3 and 9. A certain degree of impaired evacuation occurred in two patients but, with adequate training, this improved and did not affect patient satisfaction. CONCLUSION: The ABS is a good option for reconstruction of patients previously treated with an APR. As compared to electrostimulated graciloplasty the ABS technique seems to be easier to perform and more acceptable for the patients, although the cost of the device is still high.

[Predictive and diagnostic factors of malnutrition in hemodialysis patients]

The relationship between malnutrition and inflammation is by now well established. IL-6 and, probably, other proinflammatory cytokines (mainly IL-1 and TNF) may represent the link between these two entities since these interleukins may promote loss of appetite, muscle protein breakdown and reduced hepatic synthesis of "negative" acute phase proteins like albumin, prealbumin and transferrin. IL-6 also stimulates up to 1000 fold the hepatic synthesis of "positive" acute phase proteins, mainly C-reactive Protein (CRP) and Serum Amyloid A. The association between CRP and cardiovascular mortality in the general population, as well as in haemodialysed uraemic patients, is well established. These crucial interrelationships have modified the interpretation of serum albumin concentration in the diagnosis of malnutrition; a reduced serum albumin concentration, in fact, in the presence of high CRP values should point towards a diagnosis of inflammation, though the inflammation may often induce weight loss or a condition of malnutrition. After switching most patients to a more biocompatible dialysis membrane and improvement of the quality of the dialysis fluid (by adopting hydrophobic filters at the water entry of dialysis devices and bicarbonate powder cartridges) nephrologists have focused their attention on other sources of inflammation (e.g. artificial vascular protheses, presence of infected thrombi, Clamidiae, Helicobacter Pilori, dental granulomas etc.). Starting from these assumptions the diagnosis of malnutrition, once focused mainly on serum albumin reduction, must be based on other parameters (clinical history of body mass wasting, dietary and anthropometric assessment, subjective global assessment, bioimpedance analysis etc.). All these investigations, however, must be examined together to obtain suitable information on the risk of malnutrition in dialysis patients. A comprehensive approach to malnutrition-inflammation in dialysis patients is the object of the present nephrology conference.

Improving retrieval feedback with multiple term-ranking function combination

In this article we consider methods for automatic query expansion from top retrieved documents (i.e., retrieval feedback) that make use of various functions for scoring expansion terms within Rocchio's classical reweighting scheme. An analytical comparison shows that the retrieval performance of methods based on distinct term-scoring functions is comparable on the whole query set but differs considerably on single queries, consistent with the fact that the ordered sets of expansion terms suggested for each query by the different functions are largely uncorrelated. Motivated by these findings, we argue that the results of multiple functions can be merged, by analogy with ensembling classifiers, and present a simple combination technique based on the rank values of the suggested terms. The combined retrieval feedback method is effective not only with respect to unexpanded queries but also to any individual method, with notable improvements on the system's precision. Furthermore, the combined method is robust with respect to variation of experimental parameters and it is beneficial even when the same information needs are expressed with shorter queries.

Clinical evaluation of normothermic cardiopulmonary bypass and cold cardioplegia

BACKGROUND

To evaluate the validity of normothermic cardiopulmonary bypass (CPB) associated with topical hypothermia and cold cardioplegia technique.

METHODS

In a clinical prospective trial, a consecutive series of 100 patients, homogeneous for demographics, clinical and operative data, undergoing coronary artery bypass surgery were randomized for hypothermic CPB (rectal temperature 28-32 degrees C group A, 50 patients) and normothermic CPB (rectal temperature 35-37 degrees C, group B, 50 patients). In both groups of patients cold crystalloid cardioplegic solution and topical hypothermia was used.

RESULTS

During CPB group B patients had lower systemic vascular resistance (p=0.0001); they needed a significant (p=0.0001) increase in vasocostrictive. At the removal of aortic cross-clamp, a spontaneous sinus rhythm resumed in 48% of patients in group A and in 95% of group B patients (p=0.001). To disconnect CPB, vasoconstrictive drugs were used in 10% of patients in group B and in none of patients in group A (p=0.0001); vasodilating drugs were infused in 96% of patients in group A and in 40% of patients in group B (p=0.0001). In the immediate postoperative period, positive inotropic agents were used in 67% of patients in group A and in 22% of patients in group B (p= 0.0003); group B patients showed a more physiological rewarming, reduced periods of mechanical ventilation and an easier regulation of the volemia.

CONCLUSIONS

In our clinical experience the technique of cold heart and warm body proved to be safe and effective in simplifying surgical procedures and facilitating postoperative management.

[Our trend in conservative surgery in differentiated carcinoma of the thyroid]

AIM OF THE STUDY

Report as contribution to the controversy between supporters of total thyroidectomy versus "less than total" thyroidectomy.

MATERIALS AND METHODS

42 patient operated on over six years; 35 treated with total thyroidectomy, 7 with lobohystmectomy.

RESULTS

In the patients who underwent total thyroidectomy we observed recurrent nerve lesions in 5.7%, hypoparathyroidism in 14.3% and 1 lymph nodal relapse (it was a cancer stay III); in patients who underwent lobohystmectomy, we observed 1 temporary recurrent nerve palsy (14.2%) and 1 lymph nodal relapse (14.2%).

DISCUSSION

The choice between total thyroidectomy and lobohystermectomy depends upon different goals: reduction in risk of relapse in total thyroidectomy, to minimize complications in lobohystmectomy. In our series the risk of lymph nodal relapse seems to depend more on biological characters of the tumour than surgical tech of lymphadenectomy; however, this occurrence does not change prognosis.

CONCLUSIONS

In our experience, potential multifocality of the disease, low risk of hyatrogenic lesions and easy postoperatory management make total thyroidectomy the our preferred technique. Informed consensus is mandatory in order to involve the patients to the best choice.

Regulation of Id2 gene expression by the type 1 IGF receptor and the insulin receptor substrate-1

The Id family of helix-loop-helix proteins is known to be involved in the proliferation and differentiation of several types of cells. The type 1 IGF receptor (IGF-IR) induces either proliferation or differentiation in 32D cells, a murine hemopoietic cell line, depending on the availability of the appropriate substrates for the receptor. We have previously reported that the IGF-IR regulates the expression of the Id2 gene in 32D cells. We now show that the IGF-IR controls the increase in Id2 gene expression through at least three pathways. These three pathways originate from the tyrosine residue at 950, a domain in the C-terminus, and the activation of the insulin receptor substrate-1 (IRS-1) by the receptor. IRS-1 is the preponderant signal, and its effect on Id2 gene expression requires a functional phosphotyrosine binding domain. With wild-type IRS-1, Id2 gene expression is increased, even in those cells that express IGF-I receptors defective in Id2 signaling. Rapamycin, an inhibitor of p70(S6K), a downstream effector of IRS-1 signaling, partially inhibits (but does not completely abrogate) the increase in Id2 gene expression. A mutant IRS-1 with a deletion of the Pleckstrin domain is as effective as wild-type IRS-1 in up-regulating Id2 gene expression. In addition, it seems to increase the stability of p70(S6K). Our results indicate that the IGF-IR regulates Id2 gene expression through different pathways. At least in 32D cells, increased Id2 gene expression seems to correlate more with inhibition of differentiation than with proliferation.

Hair testing for drugs of abuse: evaluation of external cocaine contamination and risk of false positives

In some laboratories hair testing may be the main method for the evaluation of individual's drug history, however, compelling evidence supports the possibility that the presence of a small amount of drug in hair can derive from external contamination. The aim of the present study is to verify if a single external contamination with a small amount of cocaine will last sufficiently long to make a contaminated subject indistinguishable from active users, and if normal washing practices together with the decontamination procedures are sufficient to completely remove the external contamination. The results obtained using the decontamination methods suggested in literature demonstrate that significant concentrations of cocaine (>1 ng/mg) and moderate quantities of benzoylecgonine (generally <0.5 ng/mg) are still detectable up to 10 weeks after contamination. These results question the reliability of hair testing. In fact, even using the most sophisticated decontamination procedures it is not possible to distinguish a drug-contaminated subject from an active user. Thus, while a negative result excludes both chronic use and "contact" with drugs, a positive result cannot and must not be interpreted as a sure sign of drug addiction, but should be further confirmed by urine analysis.

Multicentre retrospective analysis of the outcome of artificial anal sphincter implantation for severe faecal incontinence

BACKGROUND

A new prosthetic device, the Action artificial anal sphincter, has recently been introduced for treating severe faecal incontinence. The results of this procedure in 28 patients are presented.

METHODS

The patients underwent operation for severe faecal incontinence in four Italian university hospitals and patients were reviewed after a median follow-up of 19 (range 7-41) months.

RESULTS

Early infections occurred in four patients, requiring removal of the device in three. Dehiscence of the perineal wound occurred in nine patients. After activation of the device, the cuff had to be removed in a further four patients (for rectal erosion in two, anal pain in one and late infection in one). The cuff was accidentally broken in one patient. A new anal cuff was repositioned successfully in two patients. Overall, five patients had complete removal of the device and two removal of the cuff only. Twenty-one patients available for long-term evaluation had a major improvement in faecal continence. Median resting anal pressure increased from 27 mmHg before surgery to 32 mmHg after operation. Preoperative squeeze pressure was 42 mmHg while maximum postoperative anal pressure with the activated device was 67 mmHg. The median American Medical System incontinence score decreased significantly from 98.5 to 5.5 (P < 0.001). Similar figures were observed using the Continence Grading Scale (from 14.9 to 2.6; P < 0.001). Twelve patients developed symptoms of obstructed defaecation while two patients complained of anal pain.

CONCLUSION

Improved continence was achieved after neosphincter implantation in three-quarters of the patients. Early infection and rectal erosion, together with difficulty in evacuating, are still major concerns with this technique.

[Non-toxic multinodular goitre: which surgery?]

AIM OF THE STUDY

Evaluation of total thyroidectomy, subtotal thyroidectomy and lobectomy in the management of multinodular non-toxic goitre.

MATERIALS AND METHODS

225 patients: 101 total thyroidectomies, 64 sub-total thyroidectomies, 29 lobo-hystmectomies. Hemorrages, recurrent nerve palsies, post-operatory hypocalcemias, clinical and ultrasonographic relapses, undesired effects of ormonal therapy and hypothyroidism after partial resection (considered risk factor for recurrence) have been pointed out.

RESULTS

All three procedures showed a low incidence of recurrent nerve palsy; lobectomy didn't show post-operatory hypocalcemia, that appeared respectively in 26.6% and 23% after sub-total and total thyroidectomy. Recurrence's percentage in patients followed-up, was 18.2% after lobectomy and 12.2% after sub-total thyroidectomy, but in that group we observed 46.9% of hypothyroidism (vs. 9.1% after lobectomy) and 8.6% of undesired effects of therapy. Reoperations showed inferior laringeal palsy and post-operatory hypocalcemia significantly more elevated.

DISCUSSION

Compared to lobectomy, total thyroidectomy showed higher risk of hypoparathyroidism; compared to subtotal thyroidectomy, it showed on all occasions less incidence of complications. Endocrinological follow-up is easier after total thyroidectomy.

CONCLUSIONS

According to our results, we deem the indications for lobectomy have to be limited to the patients having solitary nodule, undoubtedly benign, without familiarity or other environmental risk factor of goitre.

DNA oxidative damage during differentiation of HL-60 human promyelocytic leukemia cells

DNA oxidative damage was measured in human promyelocytic leukemia HL-60 cells, in the same cells committed to granulocytic differentiation with dimethyl sulfoxide (DMSO) or all-trans-retinoic acid (RA) and in mature human peripheral granulocytes (HPG). DNA damage was evaluated as single strand breaks and 8-OHdG adducts, measured by single cell electrophoresis or by monoclonal antibodies, respectively. The basal levels of either marker of DNA damage were higher in undifferentiated HL-60 cells than in HPG and DMSO- or RA-differentiated cells. Treatment with H(2)O(2) increased 8-OHdG formation in all cells, but the levels of DNA damage remained higher in undifferentiated cells as compared to the differentiated ones. Three lines of evidence suggested that the higher levels of DNA damage observed in undifferentiated cells were at least in part attributable to a reduced detoxification of reactive oxygen species (ROS). First, undifferentiated cells were shown to accumulate higher levels of dichlorodihydrofluorescein-detectable ROS than HPG and DMSO- or RA-differentiated cells. Second, undifferentiated HL-60 cells were characterized by reduced levels of GSH and lower GSH/GSSG ratios as compared to the differentiated cells. Third, pretreatment of undifferentiated HL-60 cells with antioxidants such as alpha-tocopherol or beta-carotene suppressed the elevation of ROS and the formation of 8-OHdG induced by H(2)O(2). Further evidence for the importance of the oxidant/antioxidant balance was obtained by modulating the iron-catalyzed decomposition of H(2)O(2) to hydroxyl radicals in undifferentiated HL-60 cells. In fact, pretreatment with FeSO(4) increased the formation of 8-OHdG induced by H(2)O(2), whereas pretreatment with the iron chelator deferoxamine produced the opposite effect. These results illustrate correlations between the oxidant/antioxidant balance and DNA damage and suggest that the capability of a cell population to withstand oxidative stress and DNA damage may depend on its degree of differentiation.

Three-dimensional magneto-optic trap for micro-object manipulation

A magneto-optic trap for micro-objects is described. Magnetic beads were trapped by optical tweezers while being rotated by a new integrated magnetic manipulator. Rotation was achieved with eight electromagnets with tip-pole geometry. The time orbital potential technique was used to achieve rotation of magnetic beads. Trapping in three dimensions and rotation of magnetic beads on three axes are demonstrated with forces up to 230 pN and force momenta of up to 10(-16)N m . A position-detection apparatus based on an interferometric scheme provides nanometer sensitivities in a few milliseconds.

The role of the insulin receptor substrate-1 in the differentiation of rat hippocampal neuronal cells

H19-7/IGF-IR cells are rat hippocampal cells expressing a human IGF-I receptor, which differentiate to a neuronal phenotype when stimulated by IGF-I at 39 degrees C. H19-7/IGF-IR cells have low levels of expression of insulin receptor substrate-l (IRS-1), a major substrate of the IGF-IR. IGF-I induces serine-phosphorylation and down-regulation of the endogenous IRS-1 upon differentiation of H19-7/IGF-IR cells. The profound influence of IRS-1 on differentiation of H19-7/IGF-IR cells was confirmed by transfecting these cells with a plasmid expressing mouse IRS-1. Over-expression of wild type IRS-1 in H19-7/IGF-IR cells abolishes IGF-I-induced differentiation at 39 degrees C. A mutant of IRS-1 lacking the PTB domain loses the ability to inhibit the differentiation program. H19-7/IGF-IR/IRS-1 cells at 39 degrees C show a stronger and prolonged activation of Akt, when compared to H19-7/IGF-IR cells. The role of Akt in the inhibition of the differentiation program was confirmed by using the inhibitor of Class I PI3 kinases LY29400, which restores IGF-I-induced differentiation of H19-7/IGF-IR/IRS-1 cells. H19-7/IGF-IR/IRS-1 cells show a strong reduction in MAP kinases signaling, which is related to the superactivation of Akt. This was confirmed by expressing in H19-7/IGF-IR cells a constitutively active Akt, which inhibited MAP kinases activation in these cells. These experiments confirm the importance of MAPK in the mechanism of IGF-I-mediated differentiation of H19-7/IGF-IR cells

Infective endocarditis of native cardiac valves: 22 years' surgical experience

BACKGROUND AND AIM OF THE STUDY

Most previous studies on surgery for endocarditis included cases of both prosthetic and native valve endocarditis (NVE), which clearly differ in their course and prognosis.

METHODS

Between February 1979 and July 2000, 199 patients underwent surgical treatment for NVE. The native valve was replaced in 185 patients, and repaired in 14. Correlations between previous heart disease and site of NVE, site and etiology, site and embolism, and etiology and extracardiac infection were analyzed. Viability of echocardiography to identify NVE features was compared with surgical inspection. Risk factors for hospital, late mortality and recurrence were assessed by multivariate analysis, including preoperative, operative and postoperative variables.

RESULTS

Streptococci were found in 52 cases (26.1%), mostly spreading from splanchnic (n = 10) and cutaneous (n = 9) infections; Staphylococci were found in 43 cases (21.6%), mostly from cutaneous foci (n = 20). Tricuspid valve endocarditis was due to Staphylococcus sp. in all documented cases (11/15; p <0.001), while Streptococcus sp. predominated in the mitral (p = 0.026) position. Echocardiography was reliable in identifying anatomic features of NVE, except for periannular abscess (13 versus 31 found at surgery; p <0.001). Hospital mortality was 6% (n = 12): preoperative NYHA class IV (p = 0.034) and emergency surgery (p = 0.001) were significant predictors of mortality. Average follow up was 57.2+/-4.4 months and was 96.3% complete. There were 27 late deaths (15%). Actuarial survival was 75.7% at 10 years and 60.3% at 20 years. Low social status (p = 0.022), diabetes mellitus (p = 0.003), fever at time of surgery (p = 0.041) and persistent postoperative fever (p = 0.0002) were predictors for late mortality. Endocarditis recurred in 28 patients (15.5%), with 74.1% freedom at 10 years and 68.7% at 20 years. Drug abuse (p = 0.001), mitral endocarditis (p = 0.002), positive blood cultures (p = 0.0003), homograft implantation (p = 0.0012) and persistent postoperative fever (p <0.0001) were significant predictors for recurrence.

CONCLUSION

Preoperative conditions of patients with NVE significantly affect early and long-term outcomes. Prognosis is worsened by delayed diagnosis and operation during the active septic process.

Recurrent infective endocarditis: a multivariate analysis of 21 years of experience. arenzul@tin.it

BACKGROUND

To evaluate which variables predict recurrence of endocarditis after surgical treatment, we reviewed our 21-year experience.

METHODS

Between January 1979 and May 2000, 308 consecutive valve replacement procedures for infective endocarditis were performed in 271 patients. Univariate and multivariate time-related analyses were performed to retrospectively evaluate the role of the following variables in the development of recurrent postoperative endocarditis: gender, site of endocarditis, previous valve disease, drug abuse, diabetes, positive valve/blood cultures, sepsis, perivalvular involvement, previous embolic events, type of replacement device, and persistent postoperative fever.

RESULTS

Clinical and echocardiographic follow-up was 97.36% complete, mean follow-up time was 53.2+/-3.4 months. Recurrent endocarditis developed in 58 cases (22.5%). Variables predicting recurrence were prosthetic endocarditis (p = 0.00001), positive valve culture (p = 0.0039), and persistence of fever at the seventh postoperative day (p = 0.000001).

CONCLUSIONS

Correct protocols of antibiotic therapy guided by microbiology may reduce the incidence of recurrent endocarditis to allow for surgery on sterile tissues and to prevent prosthetic infection. Recurrence rate is not affected by the choice of valve substitute, but can be prevented by complete surgical debridement.

Serum anti-p53 autoantibodies in patients with type 1 diabetes

The presence of antibodies reacting with the p53 tumor suppressor protein has been described in patients with some autoimmune disorders. In this study we looked for serum anti-p53 antibodies in 64 patients with autoimmune type 1 diabetes mellitus within 4 mo of diagnosis. The presence of anti-p53 antibodies was observed in 6/64 (9.4%) subjects with type 1 diabetes, and in 1/44 (2.3%) subjects with other organ-specific autoimmune diseases (18 primary biliary cirrhosis, 10 autoimmune hepatitis, 16 thyroid diseases), but in none of 45 control subjects. No relationship was found between antibodies directed against islet- and non-islet-specific antigens and anti-p53 antibodies. These findings support a possible role for p53 in some autoimmune disorders.

[Functional results of colorectal and coloanal anastomosis with and without pouch]

In the last two decades one of the main targets of anorectocolonic surgery has been to develop sphincter saving procedure able to achieve good results with acceptable five-years survivals, optimal local control of the diseases and low rate of local cancer recurrence. Partially the development of new operative techniques such as low colorectal and coloanal anastomoses with or without pouch, the TME operation and the nerve sparing procedure have reach this target. In fact, often after these operations we can observe a functional syndrome called "Post Anterior Resection Syndrome". The basis of this syndrome have to researched in anatomical and physiological alterations that followed a reconstructive operation. It is characterized by frequency and fragmentation of the stool, feeling of incomplete evacuation, tenesmus and urgency. Fecal continence may be compromised to different levels: usually with alteration limited to soiling and impaired control of flatus, occasionally with loss of liquid stool, rarely with loss of solid stools. The anorectal function will be altered for long time following the surgical procedure and the stabilization of functional results may require 1-3 years. On the basis of these considerations, the authors examine the etiopathogenesis and clinical presentation of the "Post Anterior Resection Syndrome", suggesting some expedients to prevent the functional problems. Analysing our experience and a wide specific bibliography, they also underline the indispensable point to achieve a good functional results after a reconstructive procedure. The author conclude asserting that the absence of these points have to be carefully valued because, in these situations, a simply colostomy is able to guarantee a better quality of life that a colorectal/coloanal anastomoses with or without pouch but associated to functional problems.

Intracellular association of a mutant insulin-like growth factor receptor with endogenous receptors

The type 1 insulin-like growth factor receptor (IGF-IR) is emerging as a powerful survival factor against a variety of apoptotic agents in many cell types. A mutant IGF-IR designated 486/STOP is known to induce apoptosis and inhibit the growth of human tumor cells in mice. We have investigated the mechanism of action of 486/STOP. To study it, we have developed a new retroviral vector in which we have combined a self-inactivating 5'-long terminal repeat with an inducible heat-shock promoter (heat shock protein 70) from Drosophila. Using this technique, we find that the polypeptide encoded by 486/STOP is partially retained within the cell and partially secreted. However, the secreted polypeptide is subsequently taken up by the cells. In both cases, a specific intracellular interaction of 486/STOP with the endogenous IGF-IRs can be demonstrated by coimmunoprecipitation.

Activation of the IGF-IR system contributes to malignant growth of human and mouse medulloblastomas

Insulin-like growth factor I receptor (IGF-IR) has been implicated in the normal and malignant growth of many cell types including cells from the central nervous system. In the cerebellar cortex IGF-IR mRNA is found in granular cells and IGF-I stimulation is mitogenic and protects cells from low-potassium-induced apoptosis. Since primitive neuroectodermal tumors/medulloblastomas (PNETs/medulloblastomas) are suspected to originate from the external cerebellar granular layer, it is reasonable to postulate that IGF-IR and/or its signaling molecules may contribute to the transformation of these poorly differentiated cells. To study activation of the IGF-IR system in medulloblastomas, we have utilized an antibody (anti-pY1316) that specifically recognizes the phosphorylated (active) form of the IGF-IR. Medulloblastoma biopsy specimens were positive when examined immunohistochemically with anti-Y1316 antibody. Further analysis of the IGF-IR system was performed in three human (Daoy, TE-671, D283 Med) and four mouse (BsB8, BsB13, Bs-1b, Bs-1c) medulloblastoma cell lines. All the murine cell lines examined express IGF-IR and PI3-kinase at relatively normal levels, and grossly overexpress IRS-1, when compared with normal mouse cerebellum. Within 15 min following IGF-I stimulation both mouse and human cell lines phosphorylate the beta subunit of the IGF-IR, IRS-1, Akt, and MAP kinases. They respond with cell proliferation when stimulated solely with IGF-I and are strongly inhibited when challenged with a dominant negative mutant of the IGF-IR (486/STOP), or with antisense oligonucleotides against the IGF-IR mRNA.