The Actis-gouge: a simple cutting tool for proper muscular resection in hypertrophic cardiomyopathy.

BACKGROUND: Surgical treatment of hypertrophic cardiomyopathy (HC) may be challenging for the risk of surgical complications or insufficient resection. We present our cutting tool to perform proper muscular resection in HC. MATERIAL AND METHODS: Ten patients (5 males, mean age 43,1 +/- 19,6 years, range 9-70 years) were operated on for HC using this semicircular cutting device. Combined procedures were : mitral valve repair (n = 1), mitral valve replacement (n = 2), right ventricular myectomy (n = 1), aortic valve replacement (n = 1), mitral and aortic replacement (n = 1). RESULTS: There was one early death. All the surviving patients are alive over a variable follow up from 2 to 8 years, with consistent reduction of symptoms: in fact, no patient had residual angina with significant reduction of the NYHA class from 3,2 +/- 0,6 to 1,3 +/- 0,5 postoperatively (p < 0,05). Muscular resection was effective with significant reduction of sub-valvular gradient from 84.5 + 33,4 mmHg to 14,1 +/- 17,6 mmHg (p < 0,05) without complications such as complete atrio-ventricular block or ventricular septal defects. CONCLUSION: Our semicircular myotome is an effective tool to perform a safe myectomy and it avoids surgical complications such as atrio-ventricular blocks or sub-valvular injuries. Our experience suggests that this cutting tool offers a reproducible method for muscular resection and it shows appreciable effects in the reduction of sub-valvular gradient with promising results in terms of morbidity and mortality.

Transmyocardial laser revascularization. Personal experience.

BACKGROUND: Indirect revascularization is a therapeutic approach in case of severe angina not suitable for percutaneous or surgical revascularization. Transmyocardial revascularization (TMR) is one of the techniques used for indirect revascularization and it allows to create transmyocardial channels by a laser energy bundle delivered on left ventricular epicardial surface. Benefits of the procedure are related mainly to the angiogenesis caused by inflammation and secondly to the destruction of the nervous fibers of the heart. PATIENTS AND METHOD: From September 1996 up to July 1997, 14 patients (9 males - 66.7%, mean age 64.8±7.9 years) underwent TMR. All patients referred angina at rest; Canadian Angina Class was IV in 7 patients (58.3%), III in 5 (41.7%). Before the enrollment, coronarography was routinely performed to find out the feasibility of Coronary Artery Bypass Graft (CABG): 13 patients (91,6%) had coronary arteries lesions not suitable for direct revascularization; this condition was limited only to postero-lateral area in one patient submitted to combined TMR + CABG procedures. RESULTS: Mean discharge time was 3,2±1,3 days after surgery. All patients were discharged in good clinical conditions. Perfusion thallium scintigraphy was performed in 7 patients at a mean follow-up of 4±2 months, showing in all but one an improvement of perfusion defects. Moreover an exercise treadmill improvement was observed in the same patients and all of them are in good clinical conditions, with significantly reduced use of active drugs. CONCLUSION; Our experience confirms that TMR is a safe and feasible procedure and it offers a therapeutic solution in case of untreatable angina. Moreover, it could be a hybrid approach for patients undergoing CABGs in case of absence of vessels suitable for surgical approach in limited areas of the heart.

Cytokinetic and cytotoxic effects of urea on HeLa cells in suspension cultures.

Total and viable cell counts, differential mitotic cell counts, and incorporation of tritiated thymidine were used to study the kinetics of suspension cultures of HeLa cells exposed to urea concentrations of 0.5-1.5%. Aside from any nonspecific osmotic effects, urea concentrations of 1.0-1.4% exhibited significant cytokinetic and cytotoxic effects. Most characteristically, mitotic cells arrested in metaphase began to accumulate 4-6 hours after addition of urea and reached a peak at 15-18 hours. Thus when the cells were in the S-phase or at the S/G2 boundary at the time of addition of urea, they exhibited metaphase arrest. Subsequently, cultures continuously exposed to urea showed a decline in the mitotic index, indicating that the entry rate of cells into mitosis is lower than the rate at which cells escape from the mitotic block. Such cultures exhibited numerous abnormal and abortive mitoses and a decrease in growth and viability of the cell populations. In contrast to the initial single wave of arrested mitosis seen with continuous exposure to urea, intermittent exposure on alternate days resulted in successive waves of arrested metaphases and had considerably more pronounced effects on the growth and viability of the cultures.

Karyotypic comparisons of multiple tumorous and macroscopically normal surrounding tissue samples from patients with breast cancer.

Many tumor tissues are made up of genetically different cell populations, and the study of the causes and consequences of this heterogeneity must play a central role in cancer research. We have studied breast cancer clonal heterogeneity by cytogenetic analysis of 4123 cells from 52 successfully short-term-cultured tumorous, metastatic, and macroscopically normal breast tissue samples from 6 women with this disease. All 7 carcinomas (one woman had bilateral disease) contained 1 to 9 karyotypically related as well as unrelated clones, unevenly distributed among the tumor quadrants. Two clonal chromosome abnormalities were recurrent: interstitial 3p deletions were found in 5 carcinomas, whereas del(1)(q42) was detected in another 2 tumors. Both successfully analyzed metastatic lesions (one axillary lymph node and one metastasis in the subcutis) contained only one of several clones present in the primary tumor, thus exemplifying a reduction in overall karyotypic complexity during carcinoma spreading. In the case with the cytogenetically abnormal lymph node, another karyotypically unrelated clone was found to invade locally in the surrounding breast; also, histological evidence of carcinoma infiltration was seen in these tissue samples. In none of the other cases were clonal karyotypic changes found in macroscopically normal, extratumorous breast tissue. We conclude that a large proportion of breast carcinomas are polyclonal with cytogenetically distinct cell subpopulations expanding within separate domains of the growing tumor. Karyotypically disparate neoplastic cells may have different capacities to display malignancy-specific features (e.g., to grow invasively and set up distant metastases). It is presumed that their synergetic action is required for the full-blown carcinoma phenotype.

Deletion of 1p36 as a primary chromosomal aberration in intestinal tumorigenesis.

Cytogenetic analysis of short-term cultures from benign intestinal tumors revealed clonal chromosome aberrations in five colorectal adenomas, one adenoma of the papilla Vateri, and one hyperplastic polyp of the rectum. One adenoma had numerical aberrations only, but in all other tumors structural rearrangements were found that led to loss of genetic material from 1p. In three of the cases, the deletion was restricted to the 1p36 band; the rest had lost larger 1p segments. The rearrangement of chromosome 1 was the sole karyotypic anomaly in three adenomas, all with mild or moderate dysplasia, and in the hyperplastic polyp. Both adenomas that had additional aberrations beyond the 1p loss showed severe dysplasia. We conclude that cytogenetically detectable loss of genetic information from 1p36 is an early, seemingly primary, premalignant event in intestinal tumorigenesis. The fact that the adenomas with 1p- as the sole change showed only mild or moderate dysplasia and that the del(1p) was found also in the hyperplastic polyp suggests that this aberration is more related to the induction of hyperproliferation than to differentiation disturbances in the intestinal mucosa.

A poly(ether-ester) copolymer for the preparation of nanocarriers with improved degradation and drug delivery kinetics.

This paper reports the synthesis and the physicochemical, functional and biological characterisations of nanocarriers made of a novel di-block biodegradable poly(ether-ester) copolymer. This material presents tunable, fast biodegradation rates, but its products are less acidic than those of other biosorbable polymers like PLGA, thus presenting a better biocompatibility profile and the possibility to carry pH-sensitive payloads. A method for the production of monodisperse and spherical nanoparticles is proposed; drug delivery kinetics and blood protein adsorption were measured to evaluate the functional properties of these nanoparticles as drug carriers. The copolymer was labelled with a fluorescent dye for internalisation tests, and rhodamine B was used as a model cargo to study transport and release inside cultured cells. Biological tests demonstrated good cytocompatibility, significant cell internalisation and the possibility to vehiculate non-cell penetrating moieties into endothelial cells. Taken together, these results support the potential use of this nanoparticulate system for systemic administration of drugs.

Immunological properties of Andean starch films are independent of their nanometric roughness and stiffness.

Starch is a natural material extracted from roots, seeds, stems and tubers of different plants. It can be processed as a thermoplastic to produce a variety promising products for biomedical applications, including foams, sheets and films. In the present work, we investigated the immunological properties of microfilms prepared with starches extracted from six different types of Andean potatoes and their relationship with the different film-surface features. We confirmed the biocompatibility of all the films using THP-1 human monocytes, noticing only slight decrease in cell viability in two of the tested starches. We also analyzed pro-inflammatory cytokine release and immune cell surface receptor modulation on THP-1 plated onto the films. Our data show differences in the immunological profile of the same cells cultured onto the different starch films. Furthermore, we examined whether the dissimilar stiffness or the nanometric roughness of the films might influence the immune stimulation of the THP-1 monocytes. Our results demonstrate no correlation between cultured THP-1 immune activation and surface film characteristics. We conclude that different Andean native potato starch films have specific ability to interact with cell membranes of immune cells, conceivably due to the different spatial localization of amylose and amylopectin in the diverse starches.

Design and optimization of lipid-modified poly(amidoamine) dendrimer coated iron oxide nanoparticles as probes for biomedical applications.

Superparamagnetic iron oxide nanoparticles with a wide size range (2.6-14.1 nm) were synthesized and coated with the amphiphilic poly(amidoamine) PAMAM-C12 dendrimer. The resulting well dispersed and stable water suspensions were fully characterized in order to explore their possible use in biomedical applications. The structural and magnetic properties of the nanoparticles were preserved during the coating and were related to their relaxometric behaviour. The Nuclear Magnetic Resonance Dispersion (NMRD) profiles were found to be in accordance with the Roch model. The biocompatibility was assessed by means of cell viability tests and Transmission Electron Microscopy (TEM) analysis. The nanoparticles' capability of being detected via Magnetic Resonance Imaging (MRI) was investigated by means of clinical MRI scanners both in water and agar gel phantoms, and in a mouse model.

Cytogenetic analyses of secondary liver tumors reveal significant differences in genomic imbalances between primary and metastatic colon carcinomas.

To investigate if karyotypic features of secondary liver tumors may provide diagnostic information and if the cytogenetic patterns of primary and metastatic colorectal carcinomas (CRC) are different, 33 liver metastases were analyzed: 25 CRC, 4 small intestine carcinoids, 1 ovarian carcinoid, 1 lobular breast cancer, 1 head-and-neck squamous cell carcinoma, and 1 uveal malignant melanoma. Chromosomal aberrations were detected in 24 cases, whereas 5 had normal karyotypes and 4 were uninformative due to lack of mitoses. Trisomy 12 was detected in 2 small intestine carcinoids, suggesting that +12 may be of pathogenetic importance in this tumor type. The breast and head-and-neck carcinomas and the uveal melanoma displayed aberrations previously reported as characteristic in primary tumors, e.g., der(1;16) and deletion of 3p in the breast cancer, losses of 3p and 8p and partial gain of 8q in the head-and-neck carcinoma, and monosomy 3 and i(8)(q10) in the uveal melanoma, indicating that cytogenetic investigations provide important diagnostic information in secondary liver tumors. In the 18 CRC metastases with chromosomal abnormalities, the cytogenetic findings agreed well with previously reported primary CRC. Common numerical abnormalities included gains of chromosomes 7, 11, 13, and 20, and losses of Y, 4, 18, 21, and 22. Structural rearrangements most often affected chromosome bands 1p13, 1q10, 3p21, 5q10, 5q11, 7q10, 8q10, 8q11, 12q13, 16p13, 17p11, 20p13, 20p11, and 20q10, and frequently resulted in losses of 1p, 8p, and 17p, and gains of 5p, 6p, 7p, 8q, and 20q. Comparing the present cases with primary CRC previously analyzed in our department revealed that additional gains of 6p, 6q, 7p, and 20q, and losses of 1p, 4p, 4q, 8p, 18p, 18q, and 22 were more common (P < 0.05) in the metastases, suggesting that these genomic sites harbor genes of importance in the metastatic process of CRC.

Cytogenetic abnormalities and clonal evolution in an adult hepatoblastoma.

Hepatoblastomas usually occur in children < 3 years of age, and only occasional adult cases have been described. To date, 20 cytogenetically abnormal childhood hepatoblastomas have been reported. Karyotypic investigations have shown that most hepatoblastomas are diploid or hyperdiploid, often displaying trisomies for chromosomes 2 and 20. We have cytogenetically investigated an adult hepatoblastoma for which no previous karyotypic data exist. A hypertriploid stemline with multiple numerical and structural chromosomal aberrations, including +2 and +20, was found. In addition, the tumor displayed extensive clonal evolution with 11 subclones. Although the tumor thus displayed some chromosomal abnormalities commonly observed in childhood tumors, providing further support for the importance of these abnormalities in the development of hepatoblastoma, the level of genomic complexity seen in the present case has never been described in childhood hepatoblastomas and may suggest a different etiology or pathogenesis.

Karyotypic aberrations in an anal-canal malignant-melanoma and its local metastasis.

Tissue samples from a malignant melanoma of the anal canal and its local metastasis were short-term cultured and analyzed cytogenetically. Complex chromosome aberrations were found in the primary tumor, yielding the karyotype 49-50,X,-Y,der(1)t(1;13)(q44;q12),+der(2)t(2;8) (q31;q12),der(6)t(5;6)(q13;q21),+del(6)(q12q21),+7, der(8)t(6;8)(p12;p21),del(11)(p11),der(11)t(11;12) (p15;q24),der(15)t(6;15)(p21;p11-13),+der(20)t(1;20) (q12;q13),der(22)t(11;22)(p11;p11)[34]/88-100,idemx2[3]. In the local metastasis, the same near-tetraploid abnormal clone was detected, indicating that the cell population was clonally stable during tumor progression. This is the first malignant melanoma of the anal canal that has been cytogenetically characterized.

Rearrangement of chromosomal bands-3p13-14 in 2 hamartomas of the breast.

Cytogenetic aberrations have until now not been reported in mammary hamartomas. The finding of multiple, karyotypically abnormal clones in short-term cultures from 2 such tumors supports the interpretation that these are genuinely neoplastic lesions. The deletion del (3) (p13p14) and trisomy 18, both known to occur as primary chromosome abnormalities in breast carcinoma, were among the clonal changes in one case each. Since both tumors had structural abnormalities of 3p13-14, admittedly leading to different derivative chromosomes, rearrangement of this region might represent a unifying feature in the genesis of mammary hamartomas.

Thyroid hormone and retinoic acid induce the synthesis of insulin-like growth factor-binding protein-4 in prepubertal pig sertoli cells.

A large body of evidence suggests the existence of an intratesticular IGF system complete with ligands, receptors and binding proteins (IGFBPs); the aim of the present study was to evaluate tri-iodothyronine (T(3)) and retinoic acid (RA) effects on IGFBP production by Sertoli cells. A significant dose-dependent increase in IGFBP-4 mRNA levels was observed in Sertoli cells cultured in the presence of physiological concentrations of T(3) or RA. This response was inhibited by cycloheximide, indicating that de novo protein synthesis is required, as well as by actinomycin D, suggesting that the increase in mRNA levels requires transcriptional activation. As shown by ligand blot assays the stimulatory effects of both agents on IGFBP-4 mRNA expression appears to be consistent with an enhanced synthesis and secretion of IGFBP-4, thus suggesting that the transcriptional response is transduced to the protein level. Our data establish an important direct role for T(3) and RA in regulating IGFBP-4 expression and consequently IGF activity at the testis level.

Chromosome abnormalities in colorectal adenomas: two cytogenetic subgroups characterized by deletion of 1p and numerical aberrations.

Cytogenetic analysis of short-term cultures from 34 benign colorectal polyps, all histologically verified as adenomas, revealed clonal chromosome aberrations in 21 of them. Eight polyps had structural rearrangements, whereas only numerical changes were found in 13. A combination of structural and numerical chromosomal aberrations was found in three polyps. The most common numerical change was gain of chromosome 7, found either as the sole anomaly (five polyps), together with other numerical changes (six polyps), or together with structural rearrangements (two polyps). Other recurrent numerical changes were +20, +13, and monosomy 18, found in six, five, and two adenomas, respectively. Rearrangement of chromosome 1 was the most common structural change. Abnormalities involving 1p were seen in six adenomas, leading to visible loss of material in three. One adenoma had one clone with a large and another with a small 1p deletion. In three adenomas, del(1)(p36) was the only cytogenetic aberration, supporting the authors' previous conclusion that loss of one or more gene loci in band 1p36 is a common early change in colorectal tumorigenesis. Chromosome 8 was involved in structural changes in two adenomas; in one this led to loss of 8p and in the other to gain of 8q. The cytogenetic findings did not correlate in a statistically significant manner with clinicopathologic parameters, such as grade of dysplasia, macroscopic or microscopic adenoma structure, tumor size and location, or the patients' sex and age.

Cytogenetic findings in phyllodes tumors of the breast: karyotypic complexity differentiates between malignant and benign tumors.

Clonal karyotypic abnormalities were detected in short-term cell cultures from six phyllodes tumors of the breast. Whereas all five benign tumors had simple chromosomal changes, the highly malignant one had a near-triploid stemline, indicating that karyotypic complexity is a marker of malignancy in phyllodes tumors. Interstitial deletions of the short arm of chromosome 3, del(3)(p12p14) and del(3)(p21p23),were the only aberrations in two benign tumors. Cytogenetic polyclonality was detected in three benign tumors: two had cytogenetically unrelated clones, whereas the third had three different, karyotypically related cell populations as evidence of clonal evolution. The finding of clonal chromosome abnormalities in both the epithelial and connective tissue components of the phyllodes tumors indicates that they are genuinely biphasic, that is, that both components are part of the neoplastic parenchyma.

Early and late risk factors in surgical treatment of acute type A aortic dissection.

BACKGROUND: Morbidity and mortality of emergency repair of type A dissecting aneurysms of the aorta are high. This is an attempt to investigate the risk determinants of early and late results. METHODS: A series of preoperative and operative variables were retrospectively collected from the clinical records of 291 patients operated on between January 1, 1979, and December 31, 1995. Risk factors for surgical death were investigated with univariate analysis and stepwise logistic regression. Follow-up was conducted between December 1995 and February 1996. Analysis of late results was conducted by means of actuarial survival curves (life method). After removing the surgical deaths, risk factors for late deaths were analyzed by a Cox model. RESULTS: The in-hospital mortality rate was 36.1%. Significant independent determinants of operative or early death were preoperative shock, preoperative neurologic impairment, operation before 1986, perioperative bleeding, and prolonged clamping time. The 10-year survival rate was 36.9% +/- 4.4%. Twenty-six patients required repeat operation. The long-term prognosis was significantly worse in patients who needed reoperation. CONCLUSIONS: Growing awareness of this disease and quicker diagnosis have increased the number of patients with acute dissection of the ascending aorta who are taken early to operation. This new challenge must be met by better preoperative support and intraoperative monitoring, and by surgical techniques that focus on lowering the rate of late complications, for which lifelong follow-up must be provided.

Interrelationship between methodological choices and conceptual models in solid tumor cytogenetics.

Scientific methods and models are interdependent. That the techniques one uses determine which findings one gets, is evident. But equally important is the influence of our a priori expectations; they may cause us to choose inadvertently those methods that are most likely to yield results that appear to confirm an already preconceived picture of reality. The conceptual models and methods of solid tumor cytogenetics are to a large extent inherited from leukemia and lymphoma cytogenetics. We illustrate how this may bias the generation and interpretation of new findings, especially when carcinomas are investigated. These malignant epithelial tumors much more often harbor cytogenetically unrelated clones than do hematologic or mesenchymal neoplasms. Carcinoma cytogenetics is therefore extremely susceptible to selection differences, making the results heavily dependent on which sample is processed, how it is disaggregated, how and for how long the cells are cultured, and on how the analysis is performed and the results presented. This calls for more efforts to be directed toward establishing also the phenotypic nature of those cells that are being karyotyped. As one cannot yet quality-grade most clonal chromosome changes in any reliable manner, meaning that one cannot determine to what extent each aberration or each clone contributes to the neoplastic process, statements about the "true" karyotypes of tumor parenchymas should be viewed with suspicion. A complete carcinoma karyotype may be much more complex than extrapolations from the analysis of a few cells may lead one to believe.

Near-diploid karyotypes with recurrent chromosome abnormalities characterize early-stage endometrial cancer.

Cytogenetic investigation was attempted on 15 endometrial tumors. Whenever possible, a combination of direct harvesting and short-term culture (with or without prior methotrexate synchronization) was used. The analysis was successful in 13 cases: 12 carcinomas of stage I and one atypical hyperplasia. Clonal abnormalities were found in 10 tumors, whereas the remaining three showed a normal karyotype. The modal chromosome number was near-diploid. The abnormal karyotypes contained relatively simple numerical or structural aberrations in all but one tumor, a serous papillary carcinoma with multiple complex changes as well as cytogenetic evidence of intratumor heterogeneity. Gain of 1q, trisomy for chromosomes 2, 7, 10 (this trisomy was shown by in situ hybridization to be present also in a large number of interphase cells), and 12, and loss of chromosome 22 were recurrent aberrations; these are also the cytogenetic anomalies that have been consistently associated with endometrial carcinomas in previous studies. The utilization of both direct harvesting and short-term culture in several cases increased the frequency with which abnormal karyotypes were found; sometimes aberrations were found by the first method but not by the other, and vice versa. Never were different clonal anomalies found by the two approaches in the same case. Synchronization of the cultures generally led to chromosome preparations with more mitoses and of better quality. Again, no different anomalies were found in synchronized and standard cultures from the same tumor.