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Biomedical subjects

R Massa

Publications and source records attributed to R Massa.

At least 109 records · Page 6Linked to original sources
PubMed1978

Effects of prolactin on LH release in male rats.

Normal and castrated male rats were injected subcutaneously (s.c.) with a homologous preparation of prolactin (Prl) for 4 1/2 days, and serum levels of LH and FSH were measured at the end of the treatment. LH was undetectable in normal animals, injected either with Prl or with the vehicle. The treatment produced a significant reduction of the levels of LH in the castrated animals. No effect on FSH levels could be observed in either the normal or the castrated animals. The only relevant autopsy finding was a reduction of pituitary weight in normal animals treated with Prl. No effect on the weight of the testes or of the sex accessories was observed. It is suggested that Prl may directly interfere with the central mechanisms which control LH secretion.

Animals↗
PubMed1977

Metabolism of testosterone in the anterior pituitary gland and the central nervous system of the European starling (Sturnus vulgaris).

The metabolism of testosterone was studied in vitro in anterior pituitary, hypothalamic and hyperstriatal tissues taken from male European starlings in the autumn. In all the tissues studied, testosterone was converted into 5alpha-androstan-17beta-ol-3-one (5alpha-DHT), 5beta-androstan-17beta-ol-3-one (5beta-DHT), 5beta-androstane-3alpha,17beta-diol (5beta-THT), 5beta-androstane-3,-17-dione and androst-4-ene-3,17-dione. The 5alpha-DHT was produced in significantly greater amounts by the pituitary gland than by the hypothalamus and hyperstriatum. The amount of 5alpha-DHT produced, however, was very low in comparison with the amounts of 5beta-reduced metabolites. The amount of 5beta-reductase was also higher in the pituitary gland than in the two nervous tissues. The ratios between the production of 5beta-DHT, 5beta-THT and 5beta-androstane-3,17-dione were, however, different in the three tissues: 5beta-DHT was produced in the greatest quantities by the hyperstriatum, while the production of 5beta-THT, 5beta-androstane-3,17-dione and androst-4-ene-3,17-dione was greatest in pituitary tissue. The role of 5alpha- and 5beta-reduced metabolites in the pituitary gland and in the brain of birds is unknown, but some possibilities arising from the present results are discussed.

Androstane-3,17-diol↗
PubMedDate not supplied

Efficacy of an intravenous low-molecular-weight dermatan sulphate (Desmin) in patients with acute proximal deep venous thrombosis and silent pulmonary embolism. A pilot study.

Ten patients affected by proximal deep venous thrombosis were treated in an open study with a low-molecular-weight dermatan sulphate (Desmin), administered at doses of 400 mg (intravenous bolus) followed by 1200 mg/day infused intravenously for 10 days, without activated partial thromboplastin adjustment. The evolution of the deep vein thrombosis and the presence of silent pulmonary embolism were evaluated by phleboscintigraphy and lung scan, performed before treatment and after 10 days of treatment, and by repeated echocolour-Doppler examination (every 2 days during treatment). The evolution of deep vein thrombosis showed a considerable improvement; similarly, lung scan showed a substantial reperfusion of lung, with regression of perfusional deficit. Repeated echocolour-Doppler examination of the deep venous system during treatment did not document further thrombus extension in any patient. Tolerance and safety were excellent. No adverse effects were observed. These preliminary results indicate that the tested dose of Desmin can be effective in treating deep vein thrombosis and silent pulmonary embolism.

Acute Disease↗
PubMedDate not supplied

Technetium-99m tetrofosmin imaging in malignant lymphomas.

AIMS: To assess the utility of 99mTc tetrofosmin (TF) scintigraphy as a diagnostic modality in lymphomas. METHODS: Seventeen patients (14 with Hodgkin's disease and three with non-Hodgkin's lymphomas; age range, 10-59 years) were investigated. Planar and SPECT images of the supradiaphragmatic region (including neck and chest) were obtained. All patients were untreated at the time of the first scintigraphy. Follow-up scans after therapy were acquired in six patients (in five twice), so a total of 28 scintigraphic studies were performed. Mediastinal, pulmonary, cervical, supraclavicular and axillary activity was evaluated and results were compared in a blinded fashion with those of CT. RESULTS: TF imaging demonstrated pathological focal uptake at 38 sites (16 in the mediastinum, eight in the lungs, four in the axillae, eight in the supraclavicular region and two in the cervical region) in 16 of 17 untreated patients. CT identified 24 lesions (16 in the mediastinum, two in the lungs, two in the axillae, two in the supraclavicular and two in the cervical region) in 17 patients. Scintigraphy detected 22 of the 24 lesions demonstrated by CT and revealed 16 unknown tumor sites in 10 patients. The only negative pre-treatment scintigraphy result was found in a patient with axillary lymph node involvement. On the first post-treatment scintigrams there was a reduction in the number of visualized pathological sites (seven vs 16) in five of the six patients examined. The second follow-up study demonstrated only two lesions in two of the five patients examined. CONCLUSIONS: Our preliminary results indicate that TF imaging is effective in depicting supradiaphragmatic lymphoma lesions in untreated patients and suggest that serial scintigraphic studies may be suitable for monitoring response to treatment. However, larger series are needed to better define the possible role of TF scintigraphy in the follow-up of the response to therapy.

Adolescent↗
PubMedDate not supplied

Breast cancer takes up 99mTc bombesin. A preliminary report.

BACKGROUND: Several tumors including lung, prostate, ovarian, colon, and exocrine pancreatic cancer show receptors for the amphibian neurotransmitter and growth factor bombesin (BN) and its mammalian counterparts gastrin-releasing peptide and neuromedin B. Also breast cancer has been reported to show such receptors: the presence of BN receptors in primary breast cancer has been demonstrated on cultured cells and by autoradiography on breast tissue samples. Authors who have studied BN receptors in breast cancer do not agree on their frequency in primary cancer, but indicate that 100% of metastatic breast cancers show such receptors. METHODS: We examined three primary breast cancer patients with 99mTc BN and 99mTc sestamibi one week before surgery. One of them showed axillary node invasion. The same acquisition technique was used for breast and chest imaging with both radiopharmaceuticals, whereas total body images were acquired only with 99mTc BN. Also the administered radioactivity was different: 20 mCi of 99mTc sestamibi and 5-8 mCi of 99mTc BN. Dynamic images were acquired for 20 mins after iv injection with the patient in ventral decubitus and the gamma camera positioned in a lateral view, as is generally done in Khakhali's prone scintimammography. Anterior chest images were acquired for 30 mins. Prone scintimammography was performed one hour after administration of both tracers. ROIs were drawn on tumors and surrounding breast with the same technique in order to calculate the tumor to breast ratio (T/B). In addition, total body scan was performed one hour and three hours after 99mTc BN administration. All three patients underwent breast conserving surgery with lymphadenectomy. Postoperative pathologic assessment showed the following T and N stages in the three patients: T1bN0, T1c-N0, and T1cN1. RESULTS: All three cancers were imaged with both tracers. The T/B of 99mTc BN was always higher than that of 99mTc sestamibi. Chest uptake was always much higher with 99mTc sestamibi than with 99mTc BN. Comparison between 99mTc BN and 99mTc sestamibi images gave other intriguing results: in the N1 patient both tracers clearly imaged the invaded node, but on the 99mTc BM image the primary tumor was larger than on the 99mTc sestamibi image and the node was smaller. It is known that 99mTc BN is not taken up by vessels and inflammatory tissue. The time activity curves of the two tracers were significantly different in all patients, with an increase in 99mTc BN uptake in the first three to five minutes, followed by a less sharp uprise of the curve, quite similar to a plateau. CONCLUSIONS: Our first impression is that 99mTc BN is a useful breast cancer seeking agent and very promising for lymph node staging.

Aged↗
PubMedDate not supplied

Radioguided biopsy of osteoid osteoma: usefulness of imaging probe.

AIMS AND BACKGROUND: When removal of osteoid osteoma is performed with open biopsy, the surgeon can be guided by radioactivity of 99mTc-MDP (methylene D- phosphonate) acquired by a probe. MATERIAL AND METHODS: We compared the performance of a commercially available ZnCdTe probe (Neoprobe 2000) and a one-square-inch-field-of-view imaging probe (IP) on two patients undergoing open biopsy for osteoid osteoma. Triphasic bone scintigraphy was performed before operation and Neoprobe as well as IP were used in the operating room by two nuclear physicians. When the surgeon asked for guidance, each nuclear physician had to indicate a precise direction. RESULTS: The surgeon asked for guidance once in the first operation, on a patient with osteoid osteoma of the femur, and four times in the second operation, for osteoid osteoma of the acetabulum. The indications provided by IP were correct 5/5 times, whereas the commercial probe was correct 3/5 times. Both devices were able to assess the surgical radicality. After biopsy, bone samples were divided into high-count and low-count samples. Pathological examination confirmed the presence of osteoid osteoma in high-count samples. CONCLUSIONS: IP has already been used to guide biopsy, but only in breast disease. The present work confirmed its good performance also in orthopedics as a portable mini gamma camera that can be used in the operating room.

Biopsy↗
PubMedDate not supplied

[Neuropsychiatric lupus erythematosus].

Neuropsychiatric involvement in patients with Systemic Lupus Erythematosus (SLE), first mentioned by Kaposi more than 100 years ago, still remains one of the main challenge facing rheumatologist and other physicians. The diagnosis of neuropsychiatric SLE (NPSLE) is complex not only because of the considerable prevalence variation (14-80%) but also because of the wide spectrum of NP manifestations. They vary from overt neurologic alterations (seizure, psychosis), to subtle abnormalities (neurocognitive dysfunctions). Different NP manifestations result from a variety of mechanisms including antibodies, vasculitis, thrombosis, hemorrhages and cytokine-mediated damages. Of note, despite the dramatic clinical manifestations, too often changes at the morphological neuroimaging techniques are minimal and non specific. There is no one diagnostic tool specific for NPSLE and diagnosis must be based on the combinated use of immunoserological tests, functional and anatomical neuroimaging and standardized specific criteria. Symptomatic, immunosuppressive and anticoagulant therapies are the main strategies available in the management of these patients. Therapy for CNS lupus should be adjusted according to the needs of the individual patients. The coming years promise to be an important time for the development of new neuroimaging techniques and for the study of disease mechanism. An early and objective identification of brain involvement will allow for appropriate treatment to avoid severe complications.

Anti-Anxiety Agents↗
PubMedDate not supplied

99MTC [13LEU] bombesin and a new gamma camera, the imaging probe, are able to guide mammotome breast biopsy.

UNLABELLED: A pilot study has been carried out in order to verify the feasibility of scintigraphic driving for breast biopsy. A new high resolution (HR) gamma ray detector, the imaging probe (IP), and 99mTc [13Leu] Bombesin (99mTc BN), have been used to drive a mammotome biopsy needle after having fused radioisotope with digital X-ray images. IP is a mobile, high resolution, miniaturised gamma camera, whose field of view is one inch and whose spatial resolution is 2 mm. 99mTc BN is a new radiotracer derived from the well-known peptide, that has already shown very high sensitivity in detecting breast cancer. PATIENTS AND METHODS: Five patients very suspicious for breast cancer were studied. 185 MBq of 99mTc BN were i.v. injected and dynamic prone scintimammography was performed for 20 minutes with a conventional large field of view gamma camera. IP was matched with the biopsy system and digital X-ray device of a mammotome system, in order to fuse images and to use the mammotome pointer indifferently on X-ray, scintigraphic and fused images. Biopsy samples were counted and weighed: uptake was expressed as counts sec-1 gr-1. Samples were classified into high, intermediate and low uptake. Conventional histological assessment was blindly performed on the samples. RESULTS: All of the patients showed cancer. The T categorisation was T1a for two cancers and T1b for 3. Dynamic prone scintimammography with conventional gamma camera, as well as HR scintigraphy with IP showed spots of 99mTc BN uptake. Maximal mismatch between X-ray lesions and of hot spots imaged with IP before mammotome scintigraphy was 3.4 mm. All the high uptake samples and all but two of the intermediate uptake samples showed cancer, whereas histology found malignant tissue in only 2 out of the 8 low uptake samples. CONCLUSION: 99mTc BN confirms its high sensitivity in detecting breast cancer. IP is able to drive or co-drive breast biopsy when used with appropriate radiopharmaceuticals.

Aged↗
PubMedDate not supplied

Unusual phenotypic characteristic of Neisseria gonorrhoeae from male patients who have sex with men.

We describe four isolates of Ng from men who have sex with men (MSM) patients that were able to grow in the abscense of CO2, as previously was described for N. gonorrhoeae ssp. kochii. These isolates were able to grow aerobically (without any added CO2) at 37 degrees C giving small colonies after 48 hs; two of them isolated from pharynx and urethra of one patient, were also able to grow without the blood supplement in the same conditions. In these unusual isolates the major outer-membrane proteins are of the same molecular weight than Ng. These isolates could be taken for other members of the genus if not confirmed by means of these (or other) methods.

Bacteria, Aerobic↗