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Biomedical subjects

F Lombardi

Publications and source records attributed to F Lombardi.

At least 181 records · Page 10Linked to original sources
PubMed1985

Simultaneous analysis of beat by beat systemic arterial pressure and heart rate variabilities in ambulatory patients.

The analysis of power spectral density (PSD) or RR variability in the electrocardiogram (ECG) has suggested that, in the early phase of essential hypertension, sympatho-vagal interaction is characterized by a sympathetic predominance. Recently, we have developed a high fidelity, direct arterial pressure ambulatory recording system which allows a beat by beat computer analysis of arterial pressure and heart rate. A microminiature tip transducer (Millar, diameter 0.8 mm) is inserted percutaneously into the radial artery and connected to a Holter two-channel magnetic tape recorder. The tip transducer has a wide band pass (> 1 kHz), excellent stability (congruent to 2 mmHg/24 h) and does not require a perfusion line. The overall frequency response of the entire recording-reproducing system is better than 20 Hz (-3 dB). The ECG and pressure signals are analysed with automatic autoregressive modelling algorithms to provide a quantitative estimate of blood pressure and heart rate variability through the computation of the PSD. In seven hypertensive patients, systolic arterial pressure and variance were higher during the day (157 +/- 9 mmHg and 122 +/- 9 mmHg2) than during the night (122 +/- 4 mmHg and 30 +/- 3 mmHg2). The PSD of RR and of systolic arterial pressure consisted of a predominant low frequency peak (congruent to 0.09 cycles/beat) during the day, and two peaks at low and high (congruent to 0.25 cycles/beat) frequency during the night. While RR variance was similar during both day- and night-time, a predominant low frequency peak was observed during the day.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMed1984

Medulloblastoma. Results of a sequential combined treatment.

Actuarial progression-free survival rate at 5 years of a series of 34 patients with medulloblastoma treated by combined surgery, radiotherapy, and chemotherapy was 71%. No relapses were observed in 14 patients followed for more than 5 years. Treatment consisted of a short postoperative course of vincristine (VCR) and intrathecal (IT) methotrexate (MTX) followed by irradiation to the entire cranio spinal axis. Maintenance chemotherapy (CCNU, VCR, and IT MTX) was then continued to encompass 2 years from surgery. Failure occurred in nine patients: four had local recurrence, four dissemination within the central nervous system, and one widespread skeletal metastases. Poor prognostic factors such as presence of malignant cells in the cerebrospinal fluid, non-radical surgery, young age, and radiation doses less than 50 Gy to the tumor bed, did not adversely affect the outcome of patients in this series. Long-term sequelae from the treatment program could be observed in all patients, and in 58% they were severe enough to interfere with normal, active life.

Adolescent↗
PubMed1984

Global versus regional myocardial ischaemia: differences in cardiovascular and sympathetic responses in cats.

The cardiovascular and sympathetic responses to occlusions of the left main ("global" ischaemia) or distal left anterior descending ("regional" ischaemia) coronary artery were studied in 19 anaesthetised cats with chronic sinoaortic baroreceptor denervation. "Global" ischaemia, before vagotomy, resulted in a significant reduction of mean arterial pressure (MAP), left ventricular pressure (LVP), and LVdP/dtmax while sympathetic efferent impulse activity was significantly augmented during the initial 15 +/- 2 s of occlusion (early phase) and, vice versa inhibited during the subsequent 20 +/- 2 s of occlusion (late phase). Vagotomy did not modify the haemodynamic responses, however, a significant increase in sympathetic discharge was detectable during the whole occlusion period (early and late phases). "Regional" ischaemia, before vagotomy, resulted in a significant increase in sympathetic neural discharge and MAP, with no changes in left ventricular function. After vagotomy the occlusion elicited a significant increase in MAP, LVP, LVdP/dtmax and efferent sympathetic neural activity. These excitatory responses were abolished after the interruption of a large part of the cardiac sympathetic afferents. Thus coronary artery occlusion induced haemodynamic and sympathetic reflex responses that were dependent upon the interaction of opposite influences mediated by the simultaneous activation of cardiac vagal and sympathetic afferents. The extent of "ischaemic myocardium" represented a determinant factor for the prevailing type of neural response.

Action Potentials↗
PubMed1984

Serum antibodies to poliomyelitis in Italy.

A seroepidemiological survey was conducted to assess the effectiveness of the Italian nationwide immunization programme against poliomyelitis. Over 3800 serum samples were collected from persons, aged between 6 months and 79 years and residing in urban and rural areas with different socioeconomic conditions and geographic locations.A very high level of protection was found in the target population, confirming the almost 100% history of complete immunization. Almost all subjects over 30 years of age were found to have poliovirus antibodies, although they had never been vaccinated. In Naples, a higher proportion of subjects susceptible to all 3 types of virus was found in the age group 6-23 months, suggesting a delay in the administration of vaccine. This was confirmed by the analysis of the immunization history. No difference was observed between urban and rural areas, in either serological results or history of immunization.The results confirmed the higher immunogenicity of poliovirus type 2 with respect to the other two types, the effectiveness of the vaccine, and, finally, the efficiency of the operational procedures adopted for its administration.

Adolescent↗
PubMed1984

Power spectral density of heart rate variability as an index of sympatho-vagal interaction in normal and hypertensive subjects.

Instantaneous heart rate reflects sympatho-vagal influences on pace-maker activity. Hence computer analysis of heart rate variability might provide a quantitative index of that interaction. The power spectral density (PSD) estimate of heart rate variability was obtained in normal controls and in uncomplicated hypertensives, both at rest and during a non-hypotensive sympathetic stimulus (tilting). In normal controls PSD shows three major peaks of frequencies P1 = 0.07, P2 = 0.12, P3 = 0.25 cycles/beat. P1, which is associated with sympathetic activity, represents only a minor portion of total variability at rest, while becoming predominant with tilting. P2 and P3 are associated with vagal activity, and represent the major part of variability at rest, while they are reduced by tilting. In hypertensive patients PSD is altered, as P1 is already predominant at rest and increases only slightly with tilting. Thus PSD of heart rate variability is capable of detecting an early alteration in sympatho-vagal balance of cardiac control present in uncomplicated hypertension.

Adult↗
PubMed1983

Relationship between sympathetic neural activity, coronary dynamics, and vulnerability to ventricular fibrillation during myocardial ischemia and reperfusion.

The relationship between neural sympathetic discharge and vulnerability to ventricular fibrillation during myocardial ischemia and reperfusion was studied in 26 chloralose-anesthetized dogs. Preganglionic cardiac sympathetic impulse activity and ventricular fibrillation thresholds were separately determined before and during a 10-minute period of left anterior descending coronary artery occlusion and during release-reperfusion. Within 2 minutes of occlusion the ventricular fibrillation threshold was significantly decreased (from 25 +/- 1.3 to 16 +/- 2.3 mA, p less than 0.05) corresponding with the period of maximal activation of cardiac sympathetic preganglionic fibers (from 4.4 +/- 0.2 to 6.3 +/- 0.5 impulses/sec). Coronary sinus blood flow and oxygen tension decreased significantly. All these changes persisted for 5 to 6 minutes, thereafter returning to control levels despite continued obstruction of the coronary artery. A transient but significant reduction in ventricular fibrillation threshold also occurred with release of the occlusion but was unaccompanied by increases in sympathetic neural discharge. Bilateral stellectomy completely prevented the ventricular fibrillation threshold changes observed during coronary artery occlusion. However, there was no change in coronary sinus oxygen tension or blood flow. During reperfusion, stellectomy increased rather than decreased vulnerability to ventricular fibrillation. Stellectomy augmented the reactive hyperemic response to release-reperfusion. These findings indicate that enhanced cardiac sympathetic neural activity contributes to ventricular vulnerability associated with coronary artery obstruction. An opposite action results during release-reperfusion. Cardiac sympathetic neural discharge, by reducing the magnitude of reactive hyperemic response through influence on coronary vascular tone, exerts an antifibrillatory effect.

Animals↗
PubMed1983

Childhood non-Hodgkin's lymphoma: prognostic relevance of clinical stages and histologic subgroups.

Seventy-nine consecutive children with non-Hodgkin's lymphoma were treated with a uniform intensive radiotherapy-chemotherapy program including high-dose MTX and CNS prophylaxis. Burkitt-type NHL was diagnosed in 44% and convoluted cell-type NHL in 33%. Complete remission rate was 97.5%. Forty-eight of 79 children (61%) remain progression-free after 18-78 months of follow-up. Patients belonging to the Burkitt type subgroup showed a peculiar clinical behavior as well as a significantly shorter survival than the other NHL patients (3-year overall survival rates of 50% vs. 72%, respectively). Clinical stages were related to the progression-free survival. It is concluded that treatment should be tailored according to the histology (Burkitt-type NHL vs. other histologic types) and the clinical stage.

Adolescent↗
PubMed1983

Childhood rhabdomyosarcoma with meningeal extension: results of combined therapy including central nervous system prophylaxis.

Results achieved in two consecutive series of children with rhabdomyosarcoma (RMSA) of the head and neck area, presenting with meningeal involvement, are compared. The first series consisted of 12 children treated with local radiotherapy and with (mostly) polidrug systemic chemotherapy from 1969 to 1977. The second series consisted of 11 children who, besides local radiotherapy and polichemotherapy, received brain radiotherapy (30 Gy) and intrathecal (I.T.) methotrexate (MTX) as central nervous system (CNS) prophylaxis from 1978 to 1980. In the first group, 50% of patients achieved a complete remission and only one child (8%) is surviving relapse-free. In the second group, 91% of patients achieved a complete remission and seven (64%) are surviving relapse-free after a median follow-up of 32 months. The most important reason for failure in the first series was represented by the inability to achieve a persistent local control of the primary tumor. This observation and the higher doses of radiotherapy delivered to the primary tumor in the second series prevent the conclusion that the improved results are attributable entirely to the addition of CNS prophylaxis.

Adolescent↗
PubMed1982

Nasopharyngeal carcinoma in childhood.

We have retrospectively evaluated a series of 27 consecutive children observed from 1965 to 1980 with nasopharyngeal carcinoma (NPC). Histological diagnosis in each patient was undifferentiated carcinoma of nasopharyngeal type (UCNT) with prominent lymphocytic infiltration. Regional node involvement was present in 26 of 27 patients and two children presented with distant metastases. Twenty evaluable children with primary nasopharyngeal tumor with or without positive cervical nodes underwent radiotherapy (RT) with uniform criteria in technique. Adjuvant cyclophosphamide (CPM) was administered to a total of 11 children. The actuarial relapse-free survival and overall survival are 40% and 55% at four years, respectively. In this series, the most important prognostic factor was represented by the extent of the tumor in the nasopharynx. Permanent control of the primary tumor was obtained in 85% of patients. CPM given after RT did not reduce the incidence of relapse. However, the fact that 45% of patients developed distant metastases as first treatment failure suggests that combined chemotherapy should be tested in the management of NPC in children, especially when primary tumor is locally advanced.

Adolescent↗
PubMed1982

Adjuvant chemotherapy in Ewing's sarcoma patients.

At the Istituto Nazionale Tumori of Milan 60 patients with clinically localized Ewing's sarcoma were treated during 1965-1978 according to three different protocols. From 1965-1971, 18 patients received almost exclusively local therapy and 17 of 18 (94%) relapsed in a median time of 6 months. From 1971-1978 adjuvant chemotherapy according to two different drug schedules was employed after radiotherapy. Twenty-five of 42 (59%) are surviving and relapse-free at this time (follow-up 20-101 months).

Adolescent↗
PubMed1982

Sequential half-body irradiation as systemic treatment of progressive Ewing sarcoma.

Sequential half-body irradiation (HBI) to be delivered in two sessions was used in 18 consecutive patients with metastatic Ewing sarcoma who relapsed after radiotherapy and multidrug chemotherapy. The HBI program to both upper and lower hemi body was completed in 11 patients (61%). The remaining 7 patients received only one single treatment of HBI because of relapse before the completion of the treatment program. In 20 of the 29 sessions HBI was employed to treat overt metastases. The overall objective response rate was 50%. Six of 18 patients (33%) are alive from 4 to 27 months, 3 of them without evidence of disease. No severe toxicity was observed. HBI as systemic treatment was more effective in patients who relapsed while off chemotherapy, with metastases confined to the lungs or to one single bone segment.

Adolescent↗
PubMed1982

[Thermography in the follow-up of bone and soft tissue tumors].

Thermography was used for the follow-up of 16 cases of bone tumors and of 16 cases of soft tissue tumors, after conservative treatments (surgery and/or radio- and chemio-therapy). The hyperthermia, which corresponds to the primary tumor, underwent a marked reduction during the first six months after the treatment. The thermographic picture appeared normal at the first follow-up of 12/16 bone tumors and of 9/16 soft tissue tumors. The presence of local recurrencies, at 12 months distance or more, corresponded to a new hyperthermic spot and to the increase of local vascularity. Thermography is proposed as a simple and harmless procedure for the follow-up of bone and soft tissue tumors after conservative treatments.

Adolescent↗
PubMed1981

Childhood non-Hodgkin's lymphoma: long-term results of an intensive chemotherapy regimen.

Twenty-nine consecutive children with untreated non-Hodgkin's malignant lymphoma were admitted to Istituto Nazionale Tumori of Milan during the period from 1974 through 1976 and underwent treatment with chemotherapeutic regimens consisting of Adriamycin, Cytoxan, vincristine, and prednisone (two month induction phase) and 6-mercaptopurine, methotrexate, Adriamycin, vincristine, and prednisone (maintenance phase). Each patient, regardless of clinical stage of histologic subgroup, was given the same chemotherapy. The complete response rate was 66%. Due to the high incidence of recurrence of the initial bulky lymphomatous mass and of spread to the central nervous system (CNS), local radiotherapy was given to ten children and CNS prophylaxis (brain radiotherapy + intrathecal methotrexate) to 11 children. After a follow-up period in excess of 40 months, there were five disease-free survivors (17%). Each patient who had a relapse died from the disease. The main reason for first treatment failure was relapse at the level of the primary bulky tumor site or spread to the CNS. This type of CNS prophylaxis did not prevent relapse at this site.

Adolescent↗
PubMed1981

Functions of afferents in cardiovascular sympathetic nerves.

This paper contains data and discussion of the role of afferents in the sympathetic trunks from the cardiovascular complex that evoke autonomic reflex action. A description is given of these cardiovascular reflexes induced by afferents of the sympathetic trunks in neurally intact as well as spinal animals. A positive feedback hypothesis is also proposed.

Afferent Pathways↗
PubMed1981

Effects of intracoronary administration of bradykinin on the impulse activity of afferent sympathetic unmyelinated fibers with left ventricular endings in the cat.

In anesthetized and artificially ventilated cats, we recorded the impulse activity of 23 afferent sympathetic unmyelinated fibers with left ventricular endings, dissected from the left sympathetic rami T3 and T4. All fibers displayed a spontaneous discharge at a rate of 0.79 +/- 0.2 (mean +/- SE) impulses/sec. During constriction of the thoracic aorta, the discharge increased to 1.92 +/- 0.2 impulses/sec. During myocardial ischemia, produced by interruption of left main coronary artery perfusion, supplied through an extracorporeal pump, the impulse activity increased to 1.73 +/- 0.3 impulses/sec. The mean latency for this excitation was 16.5 +/- 1.5 sec. The intracoronary administration of bradykinin (5 and 10 ng/kg) elicited a marked increase in impulse activity that, following 5 ng/kg, reached 2.06 +/- 0.2 impulses/sec, after a latency of 18 +/- 2 sec and in absence of significant hemodynamic changes. Myocardial ischemia and bradykinin never revealed the existence of silent afferent fibers included in the split nerve strand. The results obtained with this experimental model indicate that the ventricular endings of these afferent sympathetic unmyelinated fibers act as "polymodal" receptors. We hypothesize that the peripheral mechanism for cardiac nociception involves intensive excitation of fibers discharging spontaneously and not recruitment of silent fibers which are purely nociceptive in function.

Action Potentials↗