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PubMedDate not supplied

[The use of radioisotope labelling for studying the feeding of sandflies (Phlebotominae) and their move into colonies of the greater gerbil (Rhombomys opimus Licht.)].

The fly off and distribution of sandflies, vectors of zoonotic cutaneous leishmaniasis after meal on great gerbils were studied by means of radioisotope techniques. The experiments were carried out near the town of Mubarek (Uzbekistan). Three Rhombomys opimus were marked by intraperitoneal injection of 14C-glycine solution. Then they were allowed to come back to their burrows. The sandflies were radioactively labelled during bloodsucking on the rodents. Fifty-seven labeled female sandflies were caught on the surface of burrows with the marked R. opimus and on 5 colony burrows at a distance of 70-280 m from it for 6 nights. Seventeen females were Phlebotomus papatasi (0.9% of all the caught females of this species) and 40 females belonged to the Paraphlebotomus subgenus (7.0%). The fly off occurred both before and against the wind. The labeled females were found on all burrows where sticky papers were placed, but their density was 16 times lower at a distance of 280 m than in the burrow colony of their release.

Animals↗
PubMed1976

An improved and simplified radioisotopic assay for the determination of free and esterified carnitine.

The radioisotopic assay for carnitine first described by Cederblad and Lindstedt (Clin. Chim. Acta. 37:235-543, 1972) and modified by Bohmer et al (Clin. Chim. Acta. 57:55-61, 1974) has been improved and simplified. As a result, the assay yields a linear response over a wide range of carnitine concentrations without the need for excessive amounts of labeled acetyl-CoA. In addition, it will measure very small quantities of carnitine even in the presence of excess acylcarnitine. The method allows rapid determination of free and esterified carnitine in small volumes of plasma (50 mul is sufficient) without the need for prior deproteinization of the samples.

Carbon Radioisotopes↗
PubMedDate not supplied

[Radioisotope encephaloscintigraphy in the diagnosis of acoustic nerve neurinomas].

The results of the employment of radiopharmaceuticals in a group of patients with acoustic neurinomas for diagnostic purposes are described. High diagnostic efficacy of the method of radioisotope encephaloscintigraphy is emphasized, the method permitting to obtain extended diagnostic information. An important advantage of the method consists in its safety and absence of contraindicaions.

Humans↗
PubMed1998

Detection of chromogranin A mRNA in small cell lung carcinoma using a new, highly sensitive in situ hybridization method with a non-radioisotope oligonucleotide probe.

BACKGROUND: Immunoreactivity for chromogranin A (Cg A) is associated with the presence of neurosecretory granules in tumor cells, but immunohistochemical staining for Cg A may be absent in small cell lung carcinoma (SCLC), which has only a few secretory granules. Localization of Cg A mRNA is a useful indicator of the site of synthesis of a particular protein and possibly the rate of synthesis, and it is not dependent on posttranslation events within the cells. However, it is difficult to detect the low levels of mRNA copies using the standard non-radioisotope (RI) oligonucleotide probe. METHODS: The authors analyzed Cg A mRNA in 20 cases of SCLC in formalin fixed, paraffin embedded tissue using a new, highly sensitive in situ hybridization method that was developed from the maximized immunohistochemistry (ImmunoMax) method. They also investigated Cg A mRNA in nonsmall cell lung carcinoma (NSCLC), including ten cases each of adenocarcinoma and squamous cell carcinoma of the lung. RESULTS: All examined SCLC tissues showed a positive reaction for Cg mRNA. No NSCLC specimens showed any positive reaction for Cg A mRNA. CONCLUSIONS: The detection of Cg A mRNA using the new, highly sensitive in situ hybridization method with a non-RI oligonucleotide probe can be used to characterize neuroendocrine differentiation of lung tumors even when the Cg A protein is not detected by immunohistochemistry. The authors believe this is a first step toward better diagnosis and treatment for patients with SCLC.

Adult↗
PubMed1977

Brain death: I. Angiographic correlation with the radioisotopic bolus technique for evaluation of critical deficit of cerebral blood flow.

An innocuous intravenous portable radioisotopic test using technetium 99m pertechnetate was employed to demonstrate the deficit of cerebral blood flow associated with brain death. The results are compared to those of bilateral carotid and vertebral angiography in 20 patients. Absence of a bolus tracing from the head in the presence of a control tracing of a bolus from the femoral artery in two successive studies one hour apart reliably correlated with the clinical and electroencephalographic findings signifying cerebral death in comatose, apneic patients. Angiography indicated absence of intracranial circulation in 10 patients. Stasis filling or retrograde emptying of arterial vessels (or both) occurred in 7 patients. There was no evidence of venous filling in any of these 17 patients; all of them had either an absent head bolus or an "intermediate tracing." Results indicate that either form of tracing represents a critical decrease of cerebral blood flow. Two other patients had evidence of severely impaired abnormal posterior fossa circulation without angiographic evidence of cerebral circulation; both of these patients had an absent head bolus. An additional patient had an unusually small head bolus, and angiography revealed extravasation of radiopaque material but no evidence of intracranial circulation. We conclude that the bolus technique is a helpful adjunct in diagnosing brain death.

Adolescent↗
PubMed2004

Randomized clinical trial comparing radioisotope occult lesion localization and wire-guided excision for biopsy of occult breast lesions.

BACKGROUND: Accurate localization of impalpable breast lesions that require biopsy is important. This randomized trial compared radioisotope occult lesion localization (ROLL) with the standard hooked-wire technique. METHODS: Ninety-five patients were randomized to receive either ROLL or wire localization of an occult breast lesion. Correct placement of isotope was confirmed by mammography and a hand-held gamma probe was used to guide the surgical excision. Radiological, surgical and pathological data were compared for accuracy, duration and ease of technique, and histopathological diagnosis. Procedure-related pain was also assessed. RESULTS: Of the 95 patients entered, 48 were randomized to ROLL and 47 to wire localization. Two ROLL procedures failed. Marking was accurate in 46 of 48 ROLL procedures and 44 of 47 of wire localizations (P = 0.242). Difficulty in localization (Likert score 2.6 for ROLL versus 4.4 for wire localization; P < 0.001) and the degree of surgical difficulty (2.6 versus 4.0; P < 0.001) were significantly less for ROLL. ROLL was associated with less pain (score 2.7 versus 3.6; P = 0.012). There were no significant differences in mean duration of operation, specimen weight, need for intraoperative re-excision or second therapeutic operation. CONCLUSION: ROLL and wire-guided localization were similarly effective for breast biopsy, but ROLL was easier for both radiologist and surgeon, and less painful for the patient.

Biopsy↗
PubMed2005

Radioisotope bone scans in the preoperative staging of hepatopancreatobiliary cancer.

BACKGROUND: The aim of the study was to determine the value of radioisotope bone scans in the preoperative staging of patients with hepatopancreatobiliary (HPB) cancer. METHODS: Bone scanning was performed as part of a routine staging protocol in 402 consecutive patients with HPB cancer over a period of 5 years. Patients with positive bone scans underwent coned radiography, computed tomography with review on bone windows, or a bone biopsy. Bone scans were reviewed along with staging investigations, surgical and histological findings. Patients were followed for a minimum of 6 months. RESULTS: There were 171 patients with colorectal liver metastases, 106 with suspected pancreatic cancer, 47 with hepatocellular cancer, 52 with gallbladder cancer or cholangiocarcinoma, and 26 with other types of HPB cancer. Bone scans were negative in 377 patients (93.8 per cent) and positive in 25 patients (6.2 per cent). Of the 25 positive scans, 16 were falsely positive as a result of degenerative bone disease. Of nine patients with a true-positive bone scan, four had locally irresectable disease and four distant metastases. In only one patient did the bone scan result alone influence the decision to resect the HPB cancer. Overall sensitivity was 100 per cent, specificity 95.9 per cent, positive predictive value 36.0 per cent and negative predictive value 100 per cent. CONCLUSION: Bone scanning should not be included in the routine staging protocol for HPB cancer.

Aged↗
PubMed2005

Detection of sentinel nodes and micrometastases using radioisotope navigation and immunohistochemistry in patients with gastric cancer.

BACKGROUND: Patients with early gastric cancer may be treated by minimally invasive surgery. This study investigated the value of sentinel node (SN) navigation surgery, including detection of micrometastases, in patients with clinical (c) T1 and T2 gastric cancer. METHODS: The day before surgery (99m)Tc-radiolabelled tin colloid was injected submucosally near the tumour. After resecting the stomach, radioisotope uptake in all dissected lymph nodes was measured during and after surgery. Micrometastasis was detected immunohistochemically using an anticytokeratin antibody. RESULTS: SNs were identified in 99 of 104 patients. The rate of identification of SNs in patients with cT1 and cT2 tumours, excluding three technical failures, was 99 and 95 per cent respectively. Lymph node metastases and/or micrometastases were found in 28 patients (15 cT1 and 13 cT2). In the 15 patients with cT1 tumours, at least one SN contained metastasis and/or micrometastasis. For cT1 tumours, the sensitivity and accuracy of detecting SNs were both 100 per cent. Six patients with cT2 tumours had false-negative results. CONCLUSION: SN navigation surgery appears to be clinically useful only for cT1 tumours. Based on SN results, the extent of lymphadenectomy may be reduced in patients with early gastric cancer.

Adult↗
PubMed2003

Laparoscopic sentinel lymph node procedure using a combination of patent blue and radioisotope in women with cervical carcinoma.

BACKGROUND: The authors evaluated the feasibility of a laparoscopic sentinel lymph node (SN) procedure with combined radioisotopic and patent blue labeling in patients with cervical carcinoma. METHODS: Thirteen women (median age, 52.5 years) with cervical carcinoma (Stage Ia2 in 1 patient, Stage Ib1 in 10 patients, Stage Ib2 in 1 patient, and Stage IIa in 1 patient) underwent a laparoscopic SN procedure using an endoscopic gamma probe after both radioactive isotope and patent blue injections. After the procedure, all patients underwent complete laparoscopic pelvic lymphadenectomy and either laparoscopic radical hysterectomy (eight patients) or the Schauta-Amreich operation (five patients). RESULTS: SNs (mean, 1.7 SNs per patient; range, 1-3 SNs per patient) were identified in 12 of 13 patients. A median of 10.5 pelvic lymph nodes per patient (range, 4-17 pelvic lymph nodes per patient) were removed. No lymph node involvement was detected in SNs with hematoxylin and eosin staining. Immunohistochemical studies identified four metastatic SNs in two patients, with micrometastases in two SNs from the first patient and isolated tumor cells in two SNs from the second patient. No false-negative SN results were obtained. CONCLUSIONS: The results of this study suggest that SN detection with a combination of radiocolloid and patent blue is feasible in patients with cervical carcinoma. The combination of laparoscopy and the SN procedure permitted minimally invasive management of early-stage disease.

Adult↗
PubMed1986

Flow cytometric and radioisotopic determinations of platelet survival time in normal cats and feline leukemia virus-infected cats.

This study demonstrates the potential usefulness of a flow cytometric technique to measure platelet survival time in cats utilizing autologous platelets labeled in vitro with fluorescein isothiocyanate (FITC). When compared with a 51Cr method, no significant differences in estimated survival times were found. Both the 51Cr and FITC-labeling procedures induced similar changes in platelet shape and collagen-induced aggregation. Platelets labeled with FITC had significantly greater volumes compared with those of glutaraldehyde-fixed platelets. These changes were primarily related to the platelet centrifugation and washing procedures rather than the labels themselves. This novel technique potentially has wide applicability to cell circulation time studies as flow cytometry equipment becomes more readily available. Problems with the technique are discussed. In a preliminary study of the platelet survival time in feline leukemia virus (FeLV)-infected cats, two of three cats had significantly reduced survival times using both flow cytometric and radioisotopic methods. These data suggest increased platelet turnover in FeLV-infected cats.

Animals↗
PubMed1976

Transfer of alcohols and ureas across the oral mucosa measured using streaming potentials and radioisotopes.

The permeability of the oral mucosa to an alcohol and a urea series was studied using radioisotope transfer and the measurement of streaming potentials. Both methods yielded similar quantitative estimates of permeability. The rate of transfer of the smallest member of both series (methanol and urea) was greater than the second member (ethanol and methylurea). In the alcohol series, permeability increased as the chain length increased from ethanol to butanol. In contrast, the permeability of the oral mucosa to ethylurea and propylurea was less than to methylurea. However, butylurea had a greater rate of transfer than either propylurea or ethylurea.

Alcohols↗
PubMed2003

Intradermal radioisotope injection is superior to subdermal injection for the identification of the sentinel node in breast cancer patients.

BACKGROUND AND OBJECTIVES: The purpose of the present study was to evaluate whether the intradermal injection of radiocolloids would improve the identification rate of sentinel nodes over the subdermal injection in breast cancer patients. METHODS: Sentinel node biopsy was performed in T2 breast cancer patients with clinically negative nodes, using subdermal or intradermal injection of radioisotopes with the peritumoral dye injection. We used Tc-99m tin colloid, with a larger particle size (0.4-5 microm), rather than sulfur colloid and colloidal albumin. RESULTS: The initial 55 patients underwent subdermal injection of radiocolloids; the next 61 patients underwent intradermal injection of radiocolloids for sentinel node biopsy. The detection rate of sentinel nodes was significantly (P = 0.048) higher in the intradermal injection group (61/61, 100%) than in the subdermal injection group (51/55, 92.7%). False-negative rates were comparable between the two groups. Lymphoscintigraphy visualized the sentinel nodes significantly (P < 0.0001) more often in the intradermal injection group (59/61, 96.7%) than in the subdermal injection group (20/54, 37.0%). CONCLUSIONS: A significantly higher identification rate of sentinel node biopsy and lymphoscintigraphy can be achieved by intradermal injection of Tc-99m tin colloid with a large particle size than by subdermal injection.

Axilla↗
PubMed1993

Non-radioisotopic quantitative RT-PCR to detect changes in mRNA levels during early mouse embryo development.

We developed a non-radioisotopic quantitative RT-PCR method with high sensitivity and reproducibility. The results of this RT-PCR were in agreement with those of the Northern blot analysis. We measured the mRNA levels of beta-actin, transferrin receptor, and two cell cycle-related genes, cyclin B and cdc25, in early mouse embryos by the RT-PCR. In late two-cell stage embryos, beta-actin, transferrin receptor and cyclin B mRNA levels were 10-20% of those in MII stage oocytes. In contrast, the cdc25 mRNA levels were not different between these stages. When we cultured mouse embryos, the presence of an RNA polymerase inhibitor, alpha-amanitin, in the medium did not affect the mRNA levels at the two-cell stage, indicating that most of the detected mRNAs in two-cell embryos were maternally derived. These results suggest that the rate of mRNA degradation is different between cyclin B and cdc25 during early embryogenesis.

Actins↗
PubMed1999

Quantitative Assessment of Protein Adsorption by Combination of the Enzyme-Linked Immunosorbent Assay with Radioisotope-Based Studies.

Protein adsorption at polymer surfaces has been investigated by means of both ELISA and radiolabeling techniques. Most of the data obtained are linearly related to each other for protein concentrations between 0.01 and 1 µg/ml, i.e., the concentration range in which the maximum amount of adsorbed active protein (ELISA) is achieved. The correlation of ELISA data with radioisotope-based measurements allows quantification of the former. Specific correlation factors are described. Adsorption is shown to be strongly dependent on the polymer/protein system. Copyright 1999 Academic Press.

Journal Article↗
PubMed1984

A case of aneurysm of the jugular and mediastinal veins--radioisotopic blood pool study of venous aneurysm.

Venous aneurysm not associated with other cardiovascular disease or trauma is a rare condition. A case is presented of bilateral jugular and mediastinal venous aneurysm, which was detected and depicted to a full extent by means of a blood-pool study with 99mTc -fibrinogen, undertaken because of concurrent thrombocytopenia. The aneurysm was confirmed by subsequent X-ray angiography and surgery. In radioisotopic blood pool study venous aneurysm, unlike arterial or aortic aneurysm, may be filled to the equilibrium state later than the appearance of the cardiac pool.

Adult↗