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PubMed1980

Quantitative gallium-67 scanning for predictive value in primary lung carcinoma.

Gallium-67 scintigraphy was performed on 87 patients with a variety of histological types of untreated primary lung carcinoma. Gallium-67 uptake was determined, allowing for differences in tumor size. Differential uptakes were found for the various tumor types, with anaplastic small-cell carcinoma having the greatest average uptake, and adenocarcinoma and anaplastic large-cell carcinoma the smallest. Gallium-67 uptake was compared with response to radiation therapy, incidence of metastasis, and host survival in 58 of the patients. From these results it is suggested that the greater the Ga-67 accumulation in the tumor, the more effective is radiation therapy in reducing tumor size. Gallium-67 scintigraphy appears to be a valuable tool in estimating the sensitivity of the tumor before radiation therapy and in indicating the prognosis following radiation therapy in patients with primary lung carcinoma.

Adenocarcinoma↗
PubMed1980

The respective roles of gallium 67 citrate scanning and diagnostic ultrasound in detecting suppurations in renal allograft recipients.

The authors report their experiments relative to the advantage of using gallium 67 scanning in the diagnosis of suppurative lesions in renal allograft recipients. Nineteen cases suggesting abscess were analyzed. In 7 cases in which abnormal isotope uptake was noted, a suppuration was detected in the area where the gallium 67 had accumulated. In 2 cases, the abnormal image corresponded to the location of a healing drained abscess, and, in 1 case of pathological uptake at the level of the graft, it was determined that the cause was chronic rejection without suppurative lesion. In 9 cases in which no abnormal focus of uptake was noted, the symptomatology suggesting abscess was eventually attributed to nonsuppurative causes (rejection, urinary fistula, etc.). It is concluded that gallium 67 scanning is a useful means of detecting suppurations in immunodepressed patients undergoing treatment with steroids which prevent the usual signs of suppuration from appearing. Generally, it can be said that diagnostic ultrasound, performed with respect to the area of abnormal gallium 67 uptake, permits optimum determination of the possibilities of an abscess existing.

Adolescent↗
PubMed1981

Radiographic and radionuclide imaging in multiple myeloma: the role of gallium scintigraphy: concise communication.

Eighteen patients with multiple myeloma were studied using radiographs of the skeletal system, technetium phosphate bone scans, and gallium-67 scintigraphy. A total of 94 sites were used as the basis for comparison in these 18 patients. Radiographic sensitivity on a patient basis was 94%, and was 82% on a site basis. Bone scans were positive in 78% of patients and in 46% of sites. Gallium scans were positive in 56% of patients and 40% of sites. In five of the 18 patients, gallium scans showed activity in abnormal sites with a greater lesion-to-nonlesion ratio than did the bone scan. In this subgroup of patients, the disease was fulminant, and all died within 3 mo of their study. The finding of high gallium uptake in osseous sites that are normal or only slightly abnormal on bone scan has served to identify a subgroup of patients with rapidly progressive disease who may benefit from alternative treatment modalities such as radiation therapy.

Bone Neoplasms↗
PubMed1980

Role of iron-binding proteins and enhanced capillary permeability on the accumulation of gallium-67.

We studied the role of the iron-binding proteins transferrin and lactoferrin and of increased capillary permeability on the accumulation of gallium-67 in rabbits. Intramuscular injection of histamine caused accumulation of gallium-67 (injected i.v. as citrate), and of Tc-99m DTPA, at the i.m. injection site. Normal saline and albumin did not. Intramuscular injection of transferrin or lactoferrin similarly caused Ga-67 uptake. No accumulation of Tc-99m DTPA was observed at the site of transferrin injection but there was a slight accumulation at the site of lactoferrin injection. Prior saturation of transferrin or lactoferrin with ferric ion abolished their effect on Ga-67 accumulation. Gallium-67, pre-bound to transferrin vitro, did not accumulate at the site of histamine or transferrin injection, but there was a slight accumulation at the lactoferrin site. Our results suggest that either increased capillary permeability or iron-binding progeins can cause local uptake of Ga-67. Since these factors are present at sites of inflammation, they may contribute to the accumulation of gallium in inflammatory lesions.

Animals↗
PubMed1980

Gallium scanning in cerebral and cranial disorders.

Gallium scanning of cranial and cerebral abnormalities is a complex topic in which neither the mechanism of gallium accumulation or the clinical utility can be clearly defined. In the tests available to the neurologist, neurosurgeon, or practitioner, the gallium brain scan, computed tomographic brain scan, or other noninvasive studies are inconclusive. Its use as a primary localization test for CNS tumors does not appear to be warranted in view of the high sensitivity reported for conventional nuclide brain scanning, as well as computed tomography. In selected cases, the use of a gallium brain scan has been helpful in the differentiation of CNS lesions, as well as the early detection of intracerebral infection. New techniques involving 67Ga may eventually prove useful in the evaluation of CNS disorders, especially in the area of quantitating the amount of abnormal brain tissue removed following craniotomy.

Bone Diseases↗
PubMed1980

[Clinical value of scintigraphic tumor diagnosis by means of test substances with tumor affinity. 2. Gallium radioisotopes].

Deriving from the principle of direct tumor visualization and the beginnings of positive imaging of malignant tumors, radiotracers with tumor affinity are distinguished by those with tumor-specific and non-specific uptake. With special regard to the tumor-specific localization of thyroid carcinomas using radioiodine (131J) and of osteoplastic bone tumors or metastases using 99m-labelled phosphate compounds, the tumor scintigraphy results mainly with radiopharmaceuticals possessing tumors affinity, however not a tumor-specific uptake. On the basis of experimental and clinical results Gallium-67, one of these tumor-seeking agents, has become most important tumor scintigraphy. The diagnostic possibilities and limitations in using Gallium-67 for tumor imaging are derived from: 1) the non-specific uptake of Gallium-67, 2) the diagnosis accuracy and its reasons, and 3) the determinant factor of viability of tumor affecting the Gallium-67 accummulation.

Brain Neoplasms↗
PubMed1981

The role of Tc-99m phosphate complexes and gallium-67 in the diagnosis and management of maxillofacial disease: concise communication.

Osteomyelitis of maxillofacial bones is difficult to differentiate from the results of trauma or malignancy, yet successful management is dependent upon early diagnosis and appropriate therapy. To determined if gallium-67 could differentiate infection from trauma or malignancy, 61 Tc-99m phosphate scans and 52 gallium-67 scans were made in 42 patients with maxillofacial disease. In all patients, definitive diagnosis was determined by surgery and/or clinical followup. Bone scans were positive in 37 patients. Gallium-67 scans were positive in 16 patients. Subsequent surgery and/or clinical followup demonstrated active osteomyelitis in 15 patients. From the data we conclude that: (a) the addition of Ga-67 scanning to the bone scans in evaluation of maxillofacial disease contributes significantly to differentiating trauma from osteomyelitis; (b) radiographic changes do not accurately reflect bone activity or differentiate osteomyelitis from trauma or malignancy; and (c) reduction in accumulation of gallium-67 in followup scans is a useful indicator for the termination of therapy in osteomyelitis.

Adult↗
PubMed1995

Multistep tumor targeting in nude mice using bispecific antibodies and a gallium chelate suitable for immunoscintigraphy with positron emission tomography.

To improve tumor:tissue ratios in immunoscintigraphy, a three-step targeting method has been developed. The reagents used were (a) a radioactive, low molecular weight chelate prepared from ionic gallium and a phenolic polyaminocarboxylic acid, which can be labeled either with the single-photon emitter 67Ga or with the short-lived positron emitter 68Ga (t1/2 = 68 min); (b) a bispecific monoclonal antibody (bs-mAb) synthesized from the F(ab)2 fragment of the 1.1ASML antibody specific for the glycoprotein CD44v associated with a rat pancreas carcinoma cell line and the F(ab') fragment of an antibody specific for the gallium chelate; and (c) the nonradioactive gallium chelate covalently coupled to transferrin, which served as a high molecular weight blocker to prevent binding of the radioactive gallium chelate to bs-mAbs in the circulation. Targeting experiments in tumor-bearing nude mice with different doses of bs-mAbs, blocker, and 67Ga chelate were adjusted to maximize tumor to tissue contrasts and tumor uptake. Compared with the biodistribution of the 131I-labeled, native 1.1ASML antibody 24 h postinjection, a schedule using 100 pmol bs-mab 24 h later 100 pmol blocker, 15 min later 16 pmol 67Ga chelate, 1 h later examination, increased tumor:blood and tumor: liver ratios by a factor of 5 while keeping the localization of radioactivity in the tumor constant (10.1% injected dose/g). High-contrast images using either 67Ga or 68Ga were obtained within 1 h. The targeting method described enables the use of the short-lived positron emitter 68Ga and thus allows the combination of an improved immunoscintigraphy and positron emission tomography.

Animals↗
PubMed1994

Spectrophotometric determination of gallium in biological materials at nanogram levels with thiocarbohydrazone derivatives.

Two spectrophotometric methods for the determination of micrograms of gallium in biological materials are described. Proposed chromogenic reagents are 1-(phenyl-2-pyridyl)carbylidene-5-resorcylidenethiocarbohydrazo ne (PPRT) and 1-(phenyl-2-pyridyl)carbylidene-5-salicylidene thiocarbohydrazone (PPST), which form yellow 1:2 (gallium: reagent) complexes. Reactions develop at pH 4.5-6.0 in a 52% (v/v) DMF solution for PPST and at pH 4.0-7.5 in a 48% (v/v) ethanol solution for PPRT. Optimum conditions for reactions are discussed for molar absorptivity values of 59000 and 65000 l.mol-1.cm-1 for PPST and PPRT, respectively. Detection limits are 8 ng/ml for PPST and 5 ng/ml for PPRT, and the range of application is 20-800 ng/ml of gallium. Advantages of the methods include simplicity, high sensitivity and relative selectivity, allowing their application in the determination of gallium in spiked biological samples, using a previous extraction step in n-butyl acetate to avoid interference from Fe(III) and Cu(II).

Animals↗
PubMed1994

Pneumocystis carinii pneumonia presenting as focal bibasilar uptake on gallium scan during aerosolized pentamidine prophylaxis.

Radionuclide imaging with gallium is commonly performed in the evaluation of patients with suspected Pneumocystis carinii pneumonia (PCP) and is known to be highly sensitive for detection of PCP. We present a patient with acquired immunodeficiency who developed PCP in the bases of both lungs while on aerosolized pentamidine prophylaxis. A gallium scan demonstrated focal uptake in the lung bases, a pattern generally not associated with PCP, and was extremely useful in guiding bronchoscopy. An aerosol ventilation scan performed after complete resolution of the clinical illness demonstrated prominent ventilatory defects in the lung bases corresponding to the regions of previous gallium uptake. We speculate that the underlying ventilatory abnormality may have contributed to poor drug delivery to the lung bases. Pneumocystis carinii pneumonia must be considered with any focal area of gallium accumulation in patients receiving aerosolized pentamidine.

AIDS-Related Opportunistic Infections↗
PubMed1993

Residual mediastinal mass in malignant lymphoma: value of magnetic resonance imaging and gallium scan.

Following treatment for mediastinal lymphoma, residual masses are defined as a mass greater than 2 cm observed on the CT scan in the absence of other evolutive signs of lymphoma. In this study, we examined 55 patients with residual mediastinal mass after optimal therapy, using gallium scan (37 cases) or magnetic resonance imaging (MRI, 44 cases). The group comprised 41 subjects with Hodgkin's disease and 14 with non Hodgkin's lymphoma, stages I and II (32 cases) and stages III and IV (23 cases); 35 subjects (64%) having bulky mediastinal involvement at diagnosis. A negative gallium scan or fibrotic signal on MRI was correlated with complete remission in 48 cases (87%). In seven of these 48 patients, MRI was not conclusive with a high signal of indeterminate tissue following radiotherapy, but four of the seven had fibrotic tissue on biopsy and none relapsed. Positive gallium scan was observed in six cases. In conclusion, we suggest performing a gallium scan at the end of induction chemotherapy and when it is negative, treatment may be continued without surgical biopsy or salvage therapy. MRI is of value when it shows fibrotic tissue but can be inconclusive.

Adolescent↗
PubMedDate not supplied

Mechanical properties and clinical performance of a gallium restorative material.

In a combination clinical/laboratory evaluation, a gallium restorative alloy (Galloy) was assessed for six mechanical properties: compressive strength, diametral tensile strength, creep, hardness, wear, and dimensional change. Laboratory tests indicated that the gallium alloy was similar to either Tytin or Dispersalloy in most respects, with the exception of lower wear and higher 7-day diametral tensile strength. In the clinical trial, all Galloy restorations were lined with a resin to prevent moisture contacting the material during the first hours after placement. All gallium restorations--class 1's only--were intact, and no teeth were fractured at the end of 1 year. There was little difference found at the 1-year evaluation compared to the 6-month results. The surface of the gallium alloy was generally rough, and many restorations exhibited some tarnish on the surface. It should be pointed out that this product has not been FDA approved at the present time and is not on the market.

Dental Alloys↗
PubMedDate not supplied

A suggested method for mixing direct filling restorative gallium alloy.

Good wettability is one of the desirable physical properties of mercury-free gallium-based alloys (Gallium Alloy GF). However, wettability, while providing good adhesion to the cavity wall, has the adverse effect of causing stickiness to the inside of the capsule during mixing, and also to the metal hand instruments used for packing. To control this stickiness the alloy mixture was treated with a small amount of alcohol using two different methods. In both groups (alcohol-added and alcohol-treated groups), 5, 10, or 15 microliters of alcohol was added. However, for the alcohol-treated group, the alcohol was shaken from the mixture. In both groups, remarkable improvement was seen in their handling properties, for the alloy mixture did not adhere to the inside of the capsule and was easily taken out as one mass. Compressive strength, tensile strength, and creep were tested in the alcohol-added/-treated groups, and compared with those of a control (conventionally mixed gallium alloy) and a high-copper amalgam (Spherical-D). All tests were done according to ISO 1559 (International Organization for Standardization, 1986), and the results were analyzed using one-way ANOVA (Duncan, P < 0.05). Surface microhardness (KHN) and dimensional change during hardening were evaluated according to ISO 1559 and compared to the control results. In mixing Gallium Alloy GF, an addition of less than 5 microliters of alcohol had the effect of preventing the alloy mixture from sticking to the inside of the capsule and remarkably enhanced the handling properties. This suggested mixing technique did not alter either the mechanical properties tested for this material or the desirable dimensional expansion that occurs during hardening.

Alloys↗
PubMed1998

Pulmonary high-resolution computed tomography versus gallium scintigraphy: diagnostic utility in the diagnosis of patients with AIDS who have chest symptoms and normal or equivocal chest radiographs.

Fifty-six consecutive symptomatic patients with AIDS referred for gallium scintigraphy were prospectively studied with chest high-resolution computed tomography (HRCT). Results of gallium and HRCT were correlated with findings of bronchoscopy or clinical follow-up for 1 month from time of discharge. Twenty-two patients were eventually diagnosed with at least one of the following: Pneumocystis carinii, cytomegalovirus, Mycobacterium avium complex, bacteria, Kaposi's sarcoma, or lymphocytic interstitial pneumonitis. HRCT was more sensitive (82%) and more specific (91%) than gallium (59% and 75%, respectively). HRCT yielded higher positive predictive values (86%) and negative predictive values (88%) than did gallium (62% and 73%, respectively). HRCT was more helpful in guiding the method of biopsy and directing the brochoscopist to the diseased lung segment that would maximize diagnostic yield.

AIDS-Related Opportunistic Infections↗
PubMed1998

[Gallium-67 (Ga-67) scintigraphy in tuberculosis and Mycobacterium avium-M. intracellulare infections in patients with HIV infections].

BACKGROUND: Diagnosis of mycobacterioses in HIV infected patients is sometimes difficult because of atypical findings. The aim of this study was to assess the utility of gallium scintigraphy in diagnosis of AIDS related mycobacterioses in patients with fever of unknown origin. PATIENTS AND METHODS: We retrospectively reviewed the scans of 220 HIV(+) patients with fever (176 males [80%] and 44 females) who were evaluated with conventional diagnostic procedures at least of a week before. RESULTS: Gallium scintigraphy was positive in 114 patients (51%) and negative in 106 (49%). Mycobacteria were isolated in 83 patients (38%), 75 of these patients (90%) had a positive scintigraphy (sensitivity 90%; specificity 71%). Positive predictive value was 66% and negative predictive value was 92%. Mycobacterium avium-M. intracellulare (MAI) and M. tuberculosis were diagnosed in 22 (29%) and 53 (71%) HIV(+) patients, respectively. Seventy one (94%) of 75 patients with mycobacterioses had gallium uptake in at least two localizations. CONCLUSIONS: 67Ga scintigraphy is very useful in HIV(+) patients with fever of unknown origin. A negative gallium scintigraphy makes unlikely the diagnosis of mycobacterioses.

AIDS-Related Opportunistic Infections↗
PubMed1998

Mechanism involved in gallium-67 (Ga-67) uptake by human lymphoid cell lines.

The gallium-67 (Ga-67) is a radionuclide used for diagnostic imaging. It is known for its ability to accumulate in inflammatory lesions and tumors, especially in lymphomas. The intracellular distribution and the uptake mechanism of Ga-67 remains a subject of discussion. In this work, we studied the mechanism of Ga-67 uptake in 4 human lymphoid cell lines: 38658, Jurkat, DG75 and U715. Our results have pointed out the heterogeneity of Ga-67 uptake among these cell lines. Using flow cytometry analysis, we reported the expression of transferrin-receptor (TfR) in each lymphoid cell line, and found a positive correlation between TfR density and the Ga-67 uptake (r = 0.99) in lymphoid cells. The anti-TfR monoclonal antibody (MoAb) blocked significantly the Ga-67 uptake in all lymphoid cell lines indicating the Ga-67 uptake as a TfR-dependent mechanism. This mechanism has been saturated with different cold gallium concentrations. A total inhibition of Ga-67 uptake was obtained at a 10(-4) M cold gallium concentration. To conclude, we have shown that the Ga-67 uptake is TfR-dependent in lymphoid cells. Thus, the gallium penetrates in lymphoid cells by an active mechanism which can be saturated.

Antibodies, Monoclonal↗
PubMed2004

Synthesis, crystal structure, and luminescent properties of a binuclear gallium complex with mixed ligands.

By introducing tridentate Schiff base ligands, a binuclear gallium complex with mixed ligands, bis(salicylidene-o-aminophenolato)-bis(8-quinolinolato)-bis-gallium(III) [Ga(2)(saph)(2)q(2)], has been synthesized and structurally characterized by single-crystal X-ray crystallography. Crystal data for C(44)H(30)Ga(2)N(4)O(6) are as follows: space group, triclinic, P; a = 11.357(3) A, b = 12.945(3) A, c = 12.947(3) A, alpha = 103.461(15) degrees, beta = 100.070(7) degrees, gamma = 96.107(18) degrees, Z = 2. This complex was identified as a dimeric complex of hexacoordinated gallium with strong intermolecular and intramolecular pi-pi stacking interactions between the pyridyl/pyridyl rings. The thermal analysis showed that Ga(2)(saph)(2)q(2) can readily form a stable amorphous glass with a high glass transition temperature (T(g) = 204 degrees C), which is 27 degrees C higher than that of tris(8-hydroxyquinolinolate)aluminum (Alq(3)). In addition, a high photoluminescence efficiency (phi(PL)) of 0.318 in DMF has been demonstrated, although the central gallium atom can result in heavy-atom quenching. Organic light-emitting diodes (OLEDs) based on this complex displayed a turn-on voltage as low as 2.5 V and a high efficiency. Even at a low doping concentration of 1%, the doped Ga(2)(saph)(2)q(2) devices with 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) as the dopant exhibited excellent red emission centered at 628 nm with improved durability, compared with the case of Alq(3) as the host. These distinguishing properties of Ga(2)(saph)(2)q(2) make it a good candidate as a novel electron-transporting and emitting material for OLEDs.

Journal Article↗
PubMed1997

Terminal Coordination of a Gallium(I) Species to a Transition Metal. Syntheses and Crystal Structures of Ru{GaCl(THF)(2)}{GaCl(2)(THF)}(2)(CO)(3).0.5THF and Ru(2){GaCl(2)(THF)}(2)(CO)(8).

The reaction of Ru(3)(CO)(12) with Ga(2)Cl(4) in the presence of gallium metal in refluxing toluene, followed by crystallization from tetrahydrofuran, produces Ru{GaCl(THF)(2)}{GaCl(2)(THF)}(2)(CO)(3).0.5 THF (1) and Ru(2){GaCl(2)(THF)}(2)(CO)(8) (2) (THF = tetrahydrofuran). The ruthenium atom in 1 has an approximately octahedral coordination environment, with meridinal arrangements of carbonyl ligands and gallium atoms. The GaCl(THF)(2) group is in a position trans to one of the GaCl(2)(THF) groups. The crystal structure of 2 consists of a linear arrangement of metal atoms in which two GaCl(2)(THF) groups are in axial positions with respect to the metal-metal bond of an Ru(2)(CO)(8) unit. Crystal data for 1: monoclinic space group P2(1)/c (No. 14), a = 17.367(3) Å, b = 12.054(2) Å, c = 16.049(3) Å, beta = 95.18(1) degrees, Z = 4, R = 0.0527, R(w) = 0.0718. Crystal data for 2: monoclinic space group P2(1)/c (No. 14), a = 11.980(1) Å, b = 6.944(1) Å, c = 16.097(3) Å, beta = 96.81(1) degrees, Z = 2, R = 0.0300, R(w) = 0.0510. The title complexes are the first compounds to contain ruthenium-gallium bonds, and compound 1 is the second structurally-characterized example of a complex in which a gallium(I) species is terminally coordinated to a transition metal.

Journal Article↗