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Biomedical subjects

J Ramiro

Publications and source records attributed to J Ramiro.

14 recordsLinked to original sources

Properties of shoe insert materials related to shock wave transmission during gait.

The influence of the mechanical characteristics of certain insole materials in the generation and transmission of heel strike impacts while walking was studied. Three insole materials were selected according to their mechanical characteristics under heel strike impacts. The selection of materials has made it possible to distinguish the effect of rigidity and loss tangent in the transmission of heel strike impacts. A lower rigidity and a high loss tangent have been shown to reduce the transmission of impacts to the tibia. A low rigidity was seen to significantly increase the transmission of impacts from tibia to forehead.

Adult↗

Dynamic study of insole materials simulating real loads.

A new methodology of biomechanical analysis of materials for shoe inserts is presented. This methodology is based on the determination of the loads applied to the materials in real situations and its simulation by means of a dynamic testing machine. Both the rigidity and the energy-absorbing characteristics of the materials are investigated as a function of frequency. This methodology is applied to the study of several commercially available viscoelastic materials intended for shoe inserts in the treatment and prevention of degenerative joint diseases. The influence of thickness is investigated as well as the frequency-dependent behavior of the materials studied. Significant differences between materials and different behavior as a function of thickness and frequency were found. Poron materials were found to have the lowest rigidity, good for adequate pressure distribution, while Noene showed the highest energy absorption. A careful selection of the thickness of Sorbothane was found to be necessary for avoiding flattening of the material.

Adult↗

Neurosurgical experience with tumours of the pineal region at Clinica Puerta de Hierro.

The clinicopathological experience with 50 cases of pineal region tumours at Clinica Puerta de Hierro is presented. In this series, 88% of the patients were evaluated by CT-scan. Pineal region tumours make up approximately 0.7% of the intracranial expansive processes in the Spanish population. The largest group of lesions appearing in this localization is that of the germinomas (38%), followed by nontumoural lesions (20%) and tumours generally considered to be of the vicinity, such as meningiomas, gliomas and metastases (18%), tumours of the pineal parenchyma (14%), and non-germinoma germinal tumours (10%). In our series, in addition to an intracranial hypertension syndrome, an ophthalmological and, to a minor degree, an endocrinological syndrome predominate in germ-cell tumours, with a cerebellar syndrome appearing in gliomas of the pineal region. All the patients in the series diagnosed as having a germinoma and treated by irradiation are alive, and free of disease, after follow-up ranging from 2 to 20 years (mean: 8 years). The experience obtained with the present series supports the opinion that, in radiosensitive tumours, surgical resection adds no therapeutic benefit to treatment with radiotherapy alone. We suggest that when dealing with a tumour of the pineal region, CT-scan and clinical assessment now permit an initial selection of patients susceptible to surgery as a first therapeutic option, indicating those patients who, because they are considered to have either a "probable germinoma" or a "tumour of uncertain diagnosis", should undergo stereotaxic biopsy or trial radiotherapy and, only when this has proved a failure, should be subjected to open surgery.

Adolescent↗

Immunotherapy of glioblastoma with intratumoural administration of autologous lymphocytes and human lymphoblastoid interferon. A further clinical study.

A clinical trial of an immunotherapy which consisted of intratumoural injections of autologous lymphocytes with human lymphoblastoid interferon was evaluated in 31 patients with intracranial glioblastoma. Immunotherapy was performed after stereotactic biopsy or surgical resection. The treatment was tolerated well by all patients. Three patients showed positive response to immunotherapy as documented by transient regression or stabilization of the tumour size on computed tomography. Nevertheless, there is no significant difference in the survival time of the patients treated with immunotherapy and those not treated. We conclude that this immunotherapeutic regimen is not beneficial in patients with glioblastoma when used as single treatment after tumoural biopsy or resection.

Brain Neoplasms↗

Histological changes in glioblastoma after intratumoral injection of autologous lymphocytes and human lymphoblastoid interferon.

Seven glioblastomas were studied between 1 and 6 months after intratumoral injection of autologous lymphocytes and human lymphoblastoid interferon. Morphological study showed a great number of lymphocytes within the tumor tissue, and interactions between lymphocytes and glioblastoma cells, suggesting a killing phenomenon. These data support the potential usefulness of adoptive immunotherapy in patients with glioblastoma by means of intratumoral administration of activated lymphoid cells.

Brain Neoplasms↗

Clinicopathological experience with pineocytomas: report of five surgically treated cases.

The clinicopathological experience associated with five cases of pineocytoma is presented. All patients were treated by surgical removal without postoperative radiotherapy. In three individuals, 2000 cGy was administered to the tumor as a presurgical diagnostic test, with no evidence of response. All cases demonstrated histological features of pineocytoma, according to the criteria of Borit et al., and of the so-called "pineocytoma with neuronal differentiation," according to the criteria of Rubinstein. The experience obtained from the present series reveals that these tumors can occur in the initial decades of life, that a cystic appearance and the presence of calcifications are distinctive features of their radiological evaluation, and that they have a good prognosis after surgical removal, even when the histological data indicate local invasion. The convenience of reserving the term "pineocytoma" for these tumors, and of including the so-called "pineocytomas without further differentiation" within the group of pineoblastomas, is suggested in order to achieve a practical clinicopathological assessment of parenchymatous pineal tumors.

Adolescent↗

Intratumoural and intraventricular human lymphoblastoid alpha interferon (HLBI) for treatment of glioblastoma multiforme.

A series of ten patients with glioblastoma multiforme were treated with human lymphoblastoid alpha interferon (HLBI) as a single therapy after partial surgical resection (5 cases) or stereotactic biopsy (5 cases). Treatment consisted of intratumoural administration of HLBI (15 x 16(6) IU) every month (8 cases) or in the continuous intraventricular infusion of HLBI (1.8 x 10(6) IU daily) in 15-day cycles (2 cases) until rapid growing of the tumour and important neurological deterioration. The treatments were well tolerated. As judged from data from control groups, the patients demonstrated no improvement in mean survival time and follow-up CT-scan showed rapid progression of the tumour in all cases.

Adult↗

Intratumoural injection of autologous lymphocytes plus human lymphoblastoid interferon for the treatment of glioblastoma.

Preliminary experience with a clinical trial of immunotherapy for glioblastoma, by means of intratumoural injection of autologous lymphocytes (AL) mixed with low doses of human lymphoblastoid interferon (HLI) is presented. In two of twelve patients, a transient reduction of tumoural volume was obtained. Morphological studies showed that injected lymphocytes remain within the tumour, and suggest tumoural lysis due to activity of natural killer (NK) cells. Clinically no significant prolongation of survival time could be achieved and, as in other series, patients with additional radiation therapy survived longer. But the morphological findings suggest that immunotherapy carrying NK-cells to contact with tumoural cells might be useful in some patients with glioblastoma. Actually no explanation can be given why only two of our cases responded positively. Regarding the otherwise poor prognosis it seems justified to continue these studies.

Adult↗

Presence and significance of NK cells in glioblastomas.

A monoclonal antibody against the surface marker IOT-10 of natural killer (NK) cells was used to investigate the presence of these cells in a series of 25 glioblastomas. In 40% of the tumors, IOT-10-positive NK cells were found in small numbers scattered among the tumor cells. The presence of IOT-10-positive NK cells was not related to the degree of lymphocytic infiltration in the tumor as demonstrated by hematoxylin and eosin staining, nor did it appear to influence the survival time of the patients studied.

Adult↗

Intrathecal injection of autologous leucocytes in glioblastoma: circulatory dynamics within the subarachnoid space and clinical results.

In part I of this report, the CSF circulatory dynamics of autologous leucocytes labelled with indium-111 and injected in the subarachnoid space, in patients operated on for glioblastoma, were studied. In the Part II, a series of 11 patients with recurrent glioblastoma was studied for evaluating the efficacy of intrathecal injection of autologous leucocytes. Six patients previously had radiotherapy. The results in Part I show that after intrathecal injection of autologous leucocytes, these cells follow throughout the subarachnoid space and pass to the systemic blood circulation, showing no evidence of colonization of the tumour or deposit in the tumoural region. The mean survival of the patients studied in Part II was 8 months. Those six patients who received radiotherapy had a mean survival of 11.4 months, and those five who received only intrathecal injection of autologous leucocytes after surgery, had a mean survival of 4 months. This results seem to demonstrate that immunotherapy, as used in this study, is ineffective in patients with glioblastoma.

Adult↗

Thoracic intradural chordoma.

A case of primary intradural chordoma at thoracic level is presented. This report confirms the presence of ectopic intradural chordomas within the spinal canal. It is necessary to include these lesions in the differential diagnosis of intradural-extramedullary tumors.

Adult↗

Intracranial metastases to the pineal region. Report of three cases.

The pineal region is one of the rarest sites in the brain for metastatic involvement of systemic malignant tumors. A review of the literature shows that approximately 70 such cases have been reported previously, and most of them were diagnosed by autopsy. In this brief report we describe three cases of isolated intracranial metastasis to the pineal region that were diagnosed in patients alive. Although occurring rarely, metastatic lesions should be considered in the differential diagnosis of pineal region tumors.

Adult↗

Glioblastoma multiforme of the pineal region.

A case of glioblastoma multiforme restricted to the pineal region is presented. Although glioblastomas of the pineal region are exceedingly rare, they have to be considered in the differential diagnosis of tumors at this localization.

Brain Neoplasms↗

Extradural spinal meningiomas with intrathoracic extension. Report of two cases.

Two cases of extradural spinal meningiomas with intrathoracic extension are presented. Both cases were operated on previously for spinal epidural meningiomas. The first one showed predominantly intrathoracic growth and the second, dural invasion with protrusion through the root exit. In these cases meningiomas arose from the thoracic root exit. The surgical procedure is discussed. We advise postoperative X-ray therapy in these tumors and a long term follow-up of the patients.

Adult↗