Inhibidores de histidina decarboxilasa atenúan la actividad proangiogénica de células de Leydig tumorales: ¿Potencial terapia neoadyuvante para el tratamiento de leydigiomas? / Histidine decarboxylase inhibitors attenuate the pro angiogenic activity of Leydig tumor cells: Potential neoadjuvant therapy for the treatment of leydigiomas?

Resumen Los tumores de células de Leydig (TCL) son tumores endócrinos del intersticio testicular, cuya incidencia se encuentra en aumento. Los síntomas incluyen feminización o virilización en pacientes prepuberales, y pérdida de libido, disfunción eréctil, infertilidad y/o ginecomastia en adultos. Si bien son usualmente benignos, cuando malignizan en adultos no responden a radio y quimioterapia. Múltiples trabajos han reportado que la histidina decarboxilasa (HDC), enzima que cataliza la conversión de L-histidina en histamina (HA), tiene un rol importante en el desarrollo de tumores. A su vez, en nuestro laboratorio demostramos que la HA induce la proliferación de células de Leydig tumorales (CLT) murinas, mientras que la inhibición de HDC disminuye su proliferación y capacidad esteroidogénica. Además, observamos elevada expresión de HDC en TCL pediátricos vs. controles de distintos estadios de madurez sexual; y se ha descrito que ratones knock out para HDC poseen una angiogénesis incompleta. Para evaluar el rol de HDC en la modulación de la angiogénesis se empleó la línea de CLT de rata R2C, principal modelo utilizado en estudios de Leydigioma. También se realizaron estudios en TCL pediátricos. Los medios condicionados por las CLT R2C estimularon la angiogénesis tanto in vitro como in vivo (empleando HUVEC y analizando el grado de vascularización de membranas corioalantoideas de codorniz, respectivamente). El efecto in vitro se revirtió al tratar previamente las CLT R2C con α-metil-DL-histidinadihidrocloruro, inhibidor específico de HDC. A su vez, tanto la HA como los medios condicionados provenientes de TCL pediátricos, produjeron un aumento en la proliferación de las HUVEC. Nuestros resultados sugieren que las CLT producen HA y otros factores proangiogénicos, y que la inhibición selectiva de HDC atenúa la capacidad proangiogénica de las CLT. En base a estos resultados y evidencias previas del laboratorio, inhibidores específicos de HDC podrían ser utilizados como potencial terapia neoadyuvante en TCL.

ABSTRACT Leydig Cell tumors (LCT) are a rare group of endocrine tumors in the testicular interstitium. Between 1 and 3% of testicular malignances in adults and 4% in prepubertal children belong to LCT. An increasing incidence of this type of neoplasia has been reported recently all around the world. Particularly, a strong relationship between LCT and the use of anabolic steroids (which are commonly used nowadays) has been reported recently. In prepubertal boys, symptoms include feminization or virilization, depending on the major circulating steroid (estradiol or testosterone respectively). Adult patients show loss of libido, penile dysfunction, infertility and/or gynecomastia. Although the etiology still is unknown, several studies indicate that tumoral Leydig cells have an excessive production of insulin-like growth factor (IGF-1), as well as aromatase (CYP19) overexpression, which causes an enormous amount of estrogens (particularly estradiol, E2), and both factors play an important role in tumorigenesis. While usually benign, when LCT became malignant in adults they respond poorly to radio and chemotherapy. Likewise, it has been reported that both therapies increase the incidence of several tumors. All these data imply the need of new therapeutic targets to avoid the chirurgical dissection of the testes and the consequences of the hormonal therapies associated, which implicate not only the loss in reproductive function, but also psychological disorders. Several publications have reported that histidine decarboxylase (HDC), the only enzyme capable of catalyzing the conversion from L-histidine to histamine (HA) in mammals, has an important role in the development of several types of tumors, such as colorectal, breast and melanoma. At the same time, in our laboratory we have reported that HA induces cell proliferation of murine Leydig cells, and complementary, this cell proliferation decreases when inhibiting selectively HDC, as well as steroid synthesis (progesterone and E2). Also, we observed a higher expression of HDC in pediatric LCT (n = 3) than normal controls corresponding to different stages of sexual maturation (n = 9). It has been described that HDC knock out mice have an incomplete angiogenesis, and also that MA-10 Leydig cells HDC expression correlates with vascular endothelial growth factor (VEGF). The aim of this study is to improve our knowledge about the role of HDC in LCT biology, particularly, the angiogenesis modulation. We used the R2C Leydig cell line, the most used model for in vitro studies of Leydigioma, because it overexpresses CYP19 and constitutively produces high levels of IGF-1 and E2, as well as human LCT. R2C and pediatric LCT angiogenic capability was evaluated in vitro by measuring proliferation of human umbilical vein endothelial cells (HUVEC). In addition, we verified R2C cells angiogenic capability in vivo, using quail embryo vasculature (chorioallantoic membrane assay). Both models have been validated for the study of angiogenesis. Conditioned medium obtained from R2C cell culture stimulated angiogenesis in vitro (p <0.001) as well as in vivo (p <0.001). The in vitro effect was reverted with a previous treatment on the R2C cell culture using α-methyl-DL-histidine hydrochloride (α-MHD, 10 µM), a specific HDC activity inhibitor (p <0.001). Finally, human conditioned medium from pediatric LCT increased HUVEC proliferation (p <0.01). In the same way, the analyzed patients showed higher testosterone and estradiol levels than normal serum concentrations, which was in concordance to phenotypical features observed in presence of LCT. Our results indicate that tumoral Leydig cells (TLC) produce HA, as well as other angiogenic factors, and it could be stimulating the vascular endothelium. The selective inhibition of HDC attenuates the pro-angiogenic capability in TLC. Considering all these results and previous observations of our laboratory, specific inhibitors of HDC could be used, in the future, as a potential therapeutic target for the treatment of LCT.

Probiotic activity of Enterococcus faecalis CECT7121: effects on mucosal immunity and intestinal epithelial cells.

AIMS: To analyse the effect of Enterococcus faecalis CECT7121 on intestinal epithelial cells (IECs) and its effects on the mucosal immune response. METHODS AND RESULTS: Enterococcus faecalis CECT7121 showed a high adhesion capacity to completely and heterogeneously differentiated human intestinal epithelial cell line (Caco-2 cells). In addition, the contact of this bacterium with Caco-2 cells did not induce inflammatory chemokines (IL-8 and CCL-20). The presence of IgA(+) and IL-6(+) cells in the small intestine, as well as the production of inflammatory cytokines (TNFα, IL-6 and IL-12) in the gut, was determined after intragastric inoculation of Ent. faecalis CECT7121 in BALB/c mice. The administration of Ent. faecalis CECT7121 increased the number of IgA(+) cells in the intestinal lamina propria without modifying the percentage of IL-6(+) cells. No differences were observed in the cytokines measured in the intestinal extracts between probiotic-treated and control mice. CONCLUSIONS: Enterococcus faecalis CECT7121 stimulates local mucosal immunity and adheres to IECs without inducing inflammatory signals. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results indicate that, apart from its already reported systemic immune activity, Ent. faecalis CECT7121 has a modulatory effect at a local level.

Melatonin in testes of infertile men: evidence for anti-proliferative and anti-oxidant effects on local macrophage and mast cell populations.

Melatonin acting through the hypothalamus and pituitary regulates testicular function. In addition, direct actions of melatonin at the testicular level have been recently suggested. We have described that melatonin inhibits androgen production in hamster Leydig cells via melatonin subtype 1a (mel1a) receptors and the local corticotrophin-releasing hormone (CRH) system. The initial events of the melatonin/CRH signalling pathway have also been established. Melatonin and all components of the melatonergic/CRH system were also detected in Leydig cells of infertile men. This study attempted to search for additional targets of melatonin in the human testis, and to investigate the effects of melatonin on proliferation and the oxidative state in these novel target cells. To this aim, evaluation of human testicular biopsies of patients suffering from hypospermatogenesis or Sertoli cell only syndrome and cell culture studies were performed. Melatonergic receptors were found in macrophages (MACs) and mast cells (MCs) of the human testis. In biopsies of patients suffering idiopathic infertility, melatonin testicular concentrations were negatively correlated with MAC number per mm(2) and TNFα, IL1ß and COX2 expression, but positively correlated with the expression of the anti-oxidant enzymes SOD1, peroxiredoxin 1 and catalase. Melatonin inhibited proliferation and the expression of pro-inflammatory cytokines and cyclooxygenase 2 (COX2) in both the human non-testicular THP-1 MAC cell line and primary cell cultures of hamster testicular MACs. In the human HMC-1 MC line, melatonin increased the expression of anti-oxidant enzymes and decreased reactive oxygen species (ROS) generation. The results reveal new testicular targets of melatonin and describe anti-proliferative and anti-inflammatory effects of this hormone on testicular MACs. Furthermore, melatonin might provide protective effects against oxidative stress in testicular MCs.

Controversies in the evolution of paediatric-adolescent varicocele: clinical, biochemical and histological studies.

OBJECTIVE: To study hormonal and histological parameters of paediatric-adolescent varicocele in order to know certain aspects of its natural history, in an attempt to find prognostic markers of testicular damage. DESIGN AND METHODS: In a prospective cross-sectional study, we evaluated 93 children and adolescents with left unilateral varicocele and 29 healthy males as control group. All of them were classified according to Tanner stage. Scrotal Doppler in both testes and GnRH and human chorionic gonadotrophin (hCG) tests were performed in all subjects. Surgery was performed in 28 patients and homolateral testicular biopsy in 18. RESULTS: Hormonal measurements of patients with varicocele were compared with a control group for each Tanner stage. Testicular biopsy specimens were analysed by light and electron microscopy. We only observed statistical differences in Tanner III patients in basal FSH (median and range) controls=1.70 (1.10-3.70) IU/l vs varicocele=4.20 (1.00-7.50) IU/l, P<0.05 and in Tanner IV patients in LH post-GnRH: controls=11.0 (7.50-15.0) IU/l vs varicocele=18.0 (5.10-29.0) IU/l, P<0.05 and in testosterone post-hCG: controls=9.50 (7.7-10.0) ng/ml vs varicocele=12.0 (6.2-23.0) ng/ml, P<0.01. No correlation was found between the various clinical grades of varicocele and hormonal measurements for each Tanner stage. No statistically significant differences were found between pre- and post-operative hormonal findings, either in basal levels or in maximal responses. On the other hand, no morphological abnormalities were observed by electron microscopy in germ cells, tubular wall and interstice. CONCLUSIONS: There appears to be no reliable biochemical marker in children and adolescents that may predict impaired testicular function. A significant size discrepancy between both testes, testicular pain and a hyperresponse to GnRH stimulation should continue to be, for the time being, the indications for surgery.

[Role of color Doppler ultrasonography with contrast media in the monitoring of hepatocarcinoma after intralesional treatment]. / Ruolo dell'eco color Doppler con mezzo di contrasto nel monitoraggio dell'epatocarcinoma dopo trattamento intralesionale.

INTRODUCTION: We investigated the accuracy of contrast-enhanced color Doppler US in the assessment of the effectiveness of intralesional treatment of hepatocarcinomas. MATERIAL AND METHODS: Eight cirrhotic patients (HCV+), Child-Pugh class B, with a single hepatocarcinoma (< 4 cm O) and ineligible for surgical resection for various reasons (age > 70 years, reduced partial hepatic reserve, esophageal varices at risk, postoperative recurrence, no consent to the operation) were submitted to radiohyperthermia (6 patients) and percutaneous alcoholization (2 patients). The diagnosis was made with alpha-fetoprotein titration. CT, B-mode and color Doppler US with the administration of Levovist (Schering AG, Berlin, Germany). Thirty and 60 days after the treatment, both the alpha-fetoprotein titration and contrast-enhanced color Doppler US were repeated. RESULTS: Baseline color Doppler was carried out before intralesional treatment in the 8 patients and was followed by Levovist color Doppler which showed some intralesional signals, afferent vessels and rich vascularization in all the lesions. At the first follow-up (30 days), no intralesional vascular signals or afferent vessels were detected in any patient, while rich peripheral vascularization persisted in all cases, even after radiofrequency and alcoholization treatments. At 60 days' follow-up, the color Doppler pattern of all cases was the same as at 30 days. CONCLUSIONS: The absence of any intralesional vascular signals in all the treated patients and the possible demonstration of complete tumor necrosis seem to confirm the important role of contrast-enhanced color Doppler US in monitoring focal hepatic lesions after intralesional treatment.

[An update in the diagnosis and treatment of tumors of the hepatic portal]. / Attualità nella diagnosi e nel trattamento dei tumori della placca ilare.

BACKGROUND: Cholangiocarcinoma affecting the cross of the bile ducts is a tumour which has, although treatments, a high rate of mortality. METHODS: Between January 1986 and January 1996 six patients affected by Klatskin's tumor were studied; three of them underwent operation and were treated with insertion of a T tube (Kerr), whereas the other three were managed endoscopically with trans-tumoral stenting. RESULTS: The survival rate was about seven months for patients who underwent operation and fifteen months for patients managed with endoscopic stenting. CONCLUSIONS: After a review of the literature and according to personal experience, it is underlined that only an early diagnosis can achieve best results, since the latest knowledge about hepatic anatomy derived from transplants allows more extensive resections.

Reconstruction of the dysplastic spastic hip with peri-ilial pelvic and femoral osteotomy followed by immediate mobilization.

All children with cerebral palsy who had a pelvic osteotomy performed by the senior author (F.M.) from 1989 through 1991 were reviewed. Indications for operative reconstruction were failed muscle lengthening in a child younger than 8 years or a painful hip. The operative procedure included adductor muscle lengthening, varus shortening femoral osteotomy, and peri-ilial pelvic osteotomy. Patients were immediately mobilized after surgery by physical therapy. Fifty-one children had reconstruction of 49 subluxated and 21 dislocated hips. Femoral and pelvic osteotomies were performed on 59 hips, and 11 hips had only a femoral osteotomy. Forty-nine hips had adductor muscle lengthening, and 27 hips had femoral osteotomy to provide for relief of contractures. At mean follow-up of 34 months, two hips in two patients had redislocated, requiring repeated surgery. Two hips remained subluxated and asymptomatic. Twenty-three hips in 18 patients were painful before surgery. One hip continued with severe pain after surgery, requiring further surgery. Three hips continued with mild pain not requiring surgery, and 14 (82%) hips had complete pain relief. Of 37 caretakers interviewed, 80% felt the procedure was beneficial and would recommend it to others. Eight percent were uncertain, and 6% (two caretakers) thought it was not helpful.

Serum luteinizing hormone pulsatility and intratesticular testosterone and oestradiol concentrations in idiopathic infertile men with high and normal follicle stimulating hormone serum concentrations.

The purpose of the study was to evaluate pulsatile luteinizing hormone (LH) release and intratesticular concentrations of testosterone and oestradiol in infertile men, to determine if alterations in gonadotrophin secretion are associated with changes in the testicular concentrations of steroids. Patients with idiopathic oligo/azoospermia were divided into a high follicle stimulating hormone (FSH) group (n = 5) and a normal FSH group (n = 6). Blood samples were taken every 15 min for 6 h to determine LH, FSH, testosterone, oestradiol, sex hormone binding globulin, bioactive LH and bioavailable testosterone. The patients underwent a bilateral testicular biopsy for histological assessment and to determine testosterone and oestradiol concentrations. Serum measurements were compared with those of seven fertile men. The high FSH group had a higher concentration of serum LH and oestradiol than normal men (P < 0.01) and showed a lower frequency of LH pulses than the normal FSH group and control men (P < 0.01). Intratesticular oestradiol was higher in the high FSH group (P < 0.001), with a lower testosterone/oestradiol ratio (P < 0.01). Patients showed a negative correlation between the serum testosterone/LH ratio and FSH (r = -0.75; P < 0.01) and a positive correlation between the testicular oestradiol concentration and serum FSH (r = 0.86; P < 0.01). The histopathological examination only showed a smaller tube diameter in the high FSH group (P < 0.05). These data seem to indicate that a higher intratesticular concentration of oestradiol with a lower testosterone/oestradiol ratio in the high FSH group could have a deleterious effect on spermatogenesis.

[Hormonal markers of early-stage osteitis fibrosa in patients on hemodialysis]. / Indici ormonali di osteite fibrosa in fase iniziale nel paziente emodializzato.

The diagnosis of renal osteodystrophy is straightforward when the disease has reached an advanced stage and the pathology is extremely difficult to treat, whereas it is considerably more complex during the early stages. A study was carried out to assess the sensitivity of some biochemical, hormonal and instrumental markers in the early diagnosis of osteitis fibrosa in patients undergoing hemodialysis due to chronic renal insufficiency. Of these markers, the assay of whole molecule PTH appeared to be the most sensitive and specific biological marker.

[Use of ultrafiltration in refractory cardiac decompensation]. / Impiego dell'ultrafiltrazione nello scompenso cardiaco refrattario.

Traditional therapy for heart failure (diuretics, digitalic compound, vasodilators, inodilatory ACE-inhibitors) cannot arrest the progressive overloading of the circulatory system so that it is inevitable that a refractory stage to all forms of treatment will be reached when more specialised techniques, such as heart transplant and ultrafiltration will be needed. The paper reports the results obtained in 13 patients in ultrafiltration treatment for refractory heart failure: in the majority of these, a marked improvement in general conditions (edema, dyspnea) was recorded together with a regression from class 5 to class 3 NYHA in 5 patients, and to class 2 for others. The ultrafiltration method in spite of not altering the prognosis which remains negative in these patients, allow those waiting for heart transplant to survive and may improve their chances of surviving heart surgery.

Progress of brown tumors in patients with chronic renal insufficiency undergoing dialysis.

In a group of 73 patients, affected by chronic renal insufficiency, whose skeleton was periodically checked, three cases of brown tumors were found. These cases demonstrated a variety of locations that were involved, especially the pelvis, ribs and mandible. During therapeutic treatment the brown tumors presented a different behavior; while some lesions tended toward complete sclerosis, others increased in size and in both instances new lesions appeared. Parathyroidectomy, carried out in two patients, determined a definitive sclerosis of these lesions. Brown tumors also correlate with high PTH levels and with lesions from osteitis fibrosa.

Synaptonemal complex karyotyping in an oligospermic patient with heterochromatin duplication in chromosome n§ 9

Se ha realizado el análisis de complejos sinaptonépticos en espermatocitos de un paciente con oligospermia severa de etiologéa desconocida y portador de un polimorfismo de la heterocromatina paracentrométrica del cromosoma 9. La espermatogénesis del paciente está disminuida en las espermátidas, que presenta anormalidades ultraestructurales en especial en la condensación de la cromatina. En los espermatocitos en paquitene temprano hay un lazo muy visible y asimétrico en el bivalente 9, que en paquitene tardío desaparece frecuentemente, probablemente por un proceso de reajuste sináptico. El lazo es debido a que uno de los elementos es en promedio 7.02% mayor que el otro y que la media de los elementos 9 normales. Esta diferencia indica la presencia de un reordenamiento cromosómico en estado heterocigótico en la región paracentromérica del brazo largo del par 9, que corresponde probablemente a una duplicación en tánden de alrededor del 50% de la zona heterocromática normal. La extensión del lazo sugiere que puede sobrepasar el centrómero y ocupar un segmento del brazo corto. Si bien no es posible asegurar la existencia de una asociación causal entre la anomalía y la hipoespermatogénesis, esta observación se suma a otras sobre inversiones pericéntricas con lazos asinápticos en paquitene, en las cuales hay severa oligospermia o azoospermia. Sobre esta base se sugiere un estudio análogo en otros pacientes portadores de polimorfismos del 9

In vivo selection and characterization of a murine mammary tumor subline with high potential for spontaneous lymph node metastasis.

A transplantable mammary adenocarcinoma, grown in Balb/c mice, with a marked enhancement in its draining lymph node metastatic ability (MM3LN), was obtained through an in vivo procedure from a variant tumor moderately metastatic to lymph nodes (MM3). Both MM3 and MM3LN presented a similar latency and tumor growth rate and reached the same tumor mean diameter at death. MM3LN tumor-bearing mice exhibited a larger mean survival time. The new variant showed a 2.5-fold higher incidence of tumor-draining lymph node metastases than MM3 line, with no differences in the incidence of lung metastases. Morphology as well as cytogenetic and in vitro adhesion properties were studied in order to characterize the new subline. This murine tumor model has potential application in the study of the metastatic process in lymphoid tissue.

[Radiologic changes in the pelvis of patients with chronic renal insufficiency undergoing periodic dialysis]. / Le alterazioni radiologiche del bacino nei pazienti affetti da insufficienza renale cronica sottoposti a dialisi periodica.

Bone alterations in the patients undergoing periodic dialysis represent a frequent and invalidating complication and cause the pattern called uremic osteodystrophy. In this study we have examined 173 pelvic X-rays of 73 patients affected with chronic renal insufficiency and undergoing periodic dialysis. The results indicate the presence of all the lesions characterizing uremic osteodystrophy. Arterial calcifications and osteoporosis are the most frequent patterns; with various incidence, osteomalacia, osteitis fibrosa, osteosclerosis and brown tumors are associated. In this group of patients, who were followed for many years, a non-univocal behavior was observed: next to patterns of progressive aggravation, such as vascular calcifications, phases of stabilization/improvement were observed, e.g., in case of brown tumors and osteitis fibrosa.

Laser therapy in cerebral obstructive pathology and vascular malformations: a review.

Experimental results suggest the possibility of the use of lasers in the obstructive pathology and vascular malformations of the brain.

The effects of new technologies on the surgical management of brainstem tumors.

Nuclear magnetic resonance, real-time and A-scan ultrasonography, and computerized CO2 lasers were recently introduced for diagnosis and surgical treatment of brainstem tumors. These new technologies offer many advantages: safe but aggressive surgery on the brainstem, the possibility of performing a correct histologic diagnosis, and an exact indication for radiotherapy. Eleven tumors were operated on in our series: seven were intrinsic and four protruded out from the axis. Patients with high-grade malignant tumors died from 5 to 12 months after treatment, whereas those with pilocytic astrocytoma are still alive and leading useful lives.

Effects at the periphery of the laser lesion in human brain and its tumors after CO2, Nd:YAG, and CO2 high-peak pulsed radiation.

The histological changes in various tissues irradiated with lasers are well known. Our own previous observations with the optical microscope confirm those already reported in the laser literature. If tissue is treated with various laser sources, the results are similar, with the characteristic three layers from the outside toward the inside of carbonization, coagulative necrosis, and edema. Otherwise, only the shapes and sizes of the lesions differ, with craters of different depths. In this paper, we report an ultrastructural study of the changes occurring in the periphery of the laser lesions in both normal human brain and neoplastic tissues (gliomas and meningiomas). Continuous-wave CO2 and Nd:YAG lasers were used at different exposure times and powers and the effects of high-peak pulsed CO2 laser radiation has also been investigated. The study, performed during neurosurgical procedures was mostly focused on microcirculation at 1.5-3 mm outside the area of coagulative necrosis, at the level of the edema zone. Only lesions of the blood brain barrier are produced in normal brain by CO2 radiation (power ranging from 40 to 80 W; exposure time from 3 to 10 seconds). The same results were achieved by Nd:YAG radiation of short duration (3 seconds) regardless of the power used (40 and 80 W). Long-duration Nd:YAG radiation (10 sec; power: 40-80 W) produces endoluminal phenomena leading to the complete occlusion of the capillaries. In neoplastic brain tissues, microcirculation does not seem to be impaired by CO2 radiation. More marked lesions are produced in tumors even after Nd:YAG short-time radiation. Endoluminal obliteration is observed in meningiomas and perivascular hemorrhage occurs in highly vascularized gliomas. According to these results, the risk of delayed post-operative hemorrhages, noticed in some patients with glioblastoma operated on by Nd:YAG lasers, suggests that residual tumor in the cavity should be treated by CO2 laser because of its minimal damage of microcirculation.

Treatment of cerebral arterio-venous malformations with laser.

The surgical application of the laser in the treatment of vascular diseases of the brain is based on its characteristic to perform an immediate or delayed modification of the vessel wall either by shrinking the collagenous fibres or by intraluminal thrombosis. Personal researches have been carried out to study the histological modifications of the vessel wall in normal arteries following laser irradiation with Nd:YAG. On this basis we have treated arterio-venous malformations (AVMs) in man. The laser enables radical surgery with a complete preservation of the healthy tissue surrounding the lesion because of reduced manipulation and the absence of intraoperative haemorrhage. Doppler technique and real-time ultrasonography are mostly suitable in the identification of the small deep-seated AVMs localizing the site of the malformation and the reactive glial tissue surrounding the lesion. The main indications are small AVMs located in critical areas of the brain.

Preliminary experiences with "real-time" intraoperative ultrasonography associated to the laser and the ultrasonic aspirator in neurosurgery.

Twelve cerebral lesions were operated upon with various laser sources (carbon dioxide, neodymium-yttrium-argon-garnet, and argon) and with an ultrasonic aspirator utilizing the intraoperative "real-time" ultrasonography. With the last method, the tumor was imaged just as well through the intact dura mater as on the brain surface itself, allowing a precise localization of deep intracranial lesions. A sharp selectivity on the healthy tissues is, in this way, achievable to reach the tumor, which is successively removed with the laser and ultrasonic aspirator checking the surgical maneuvers on the visual control of the ultrasonograph.