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A spectrofluorometric method to measure trace germanium in vegetables was established. Results showed that the detection limit of the method was 0.569 ng/g, the accuracy of determination on the 1 microg Ge content was +/- 3.59%. The content of Ge in vegetables could be calculated from the standard adding method without extraction when using mixed acid digestion.
A method for determination of germanium and selenium in malt powder has been developed by graphite furnace atomic absorption spectrometry with L'vov platform. While (Pd+Ni) and Pd were used as matrix modifiers,the ashing temperatures of Ge and Se were increased to 1400 and 1200 degrees C respectively,and the matrix inferences were removed. The characteristic masses are 31 pg Ge and 23pg Se(0.0044 A), the detection limits are 28pg Ge and 62pg Se (3 sigma), the precisions (n = 9) are 3. 7-5.6%(Ge) and 4.3-6.5% (Se) and the recoveries are among 90-105%.
Reports mainly from Japan, recommend germanium (Ge)-containing compounds as "anti-cancer" and "immunostimulatory" remedies. We report on a 25-tear-old woman with stage II HIV disease who consumed a total of 47 g Ge as Ge-lactate-citrate 18%. She developed severe renal insufficiency (creatinine clearance 7 ml/min/1.73 m2, proteinuria 0.28 g/d) and hepatomegaly. Biopsies revealed tubulointerstitial nephropathy with vacuolar degeneration, mainly of distal tubular epithelia, and severe liver steatosis. Tissue Ge content in kidney and liver biopsy specimens was increased 68-and 140 fold respectively. In agreement with previous reports, renal dysfunction persisted 9 months later (creatinine clearance 11 ml/min/1.73 m2).
A metal-insulator-semiconductor (MIS) structure containing an HfO2/SiO2 stack tunnel layer, isolated Germanium (Ge) nanocrystals, and an HfO2 capping layer, was obtained by an electron-beam evaporation method. A high-resolution transmission electron microscopy (HRTEM) study revealed that uniform and pronounced Ge nanocrystals had formed after annealing. Raman spectroscopy provided evidence for the formation of Ge-Ge bonds and the optimal annealing temperature for the crystallization ratio of the Ge. The electric properties of the MIS structure were characterized by capacitance-voltage (C-V) and current-voltage (I-V) measurements at room temperature. Negative photoconductivity was observed when the structure was under a forward bias, which screened the bias voltage, resulting in a decrease in the current at a given voltage and a negative shift in flat band voltage. A relatively high stored charge density of 3.27 x 10(12) cm 2 was also achieved.
The method is based on the fluorescent measurement of the product, of its reaction to morin in strong acid medium. The sensitivity of the method - 0.02 mg in the analysed sample and the accuracy, expressed by the coefficient of variation - 17.7%, show that the latter is adequate for the purposes of chemical and hygiene control on the air of the working environment. The presence of aluminium, beryllium, lead, potassium in the examined air don't stand on the way of determining the concentration of germanium.
A 51-year-old man, taking beverage containing inorganic germanium (Ge), (90-100 mg/day, total 70 g) for two years, developed body weight loss, anemia, renal dysfunction, peripheral neuropathy, myopathy, autonomic dysfunctions and multiple cranial nerve palsies. Serum CK, GOT, LDH, BUN, and creatinine levels were elevated. The cerebrospinal fluid showed albumino-cytologic dissociation. Sural nerve biopsy showed axonal degeneration, and peroneal muscle biopsy showed neurogenic changes including type 2 fiber atrophy and ragged red fibers. High level of Ge content was detected from the hair and nail by inductively coupled plasma atomic emission spectrometry. Despite discontinuation of Ge taking, the peripheral neuropathy and autonomic dysfunction progressed. The symptoms remained unchanged even in the treatment with prednisolone. These findings suggest that inorganic Ge has a serious irreversible multiple system toxicity.
We report two cases of renal failure following long-term ingestion of germanium dioxide (GeO2) and comment on eight other cases reported in Japan. Ge-induced nephropathy is characterized by insidious onset of renal failure without proteinuria or hematuria after oral intake of Ge-containing compounds for more than several months, and by degeneration of renal tubular cells with minor glomerular abnormality in histology. When patients ceased to ingest Ge compounds, renal function gradually recovered but never returned to the normal range. Serious extrarenal complication can contribute to an unfavorable prognosis.
Twenty-eight species of carboxyethyl germanium sesquioxide (Ge-132) derivatives were examined for their inhibitory effects on enkephalin-degrading enzymes that were purified from monkey brain, the longitudinal muscle layer of bovine small intestine, and human cerebrospinal fluid (CSF). A series of the sulfurized Ge-132 derivatives showed strong inhibition of these purified enzymes. The most effective ones were Ge-014 and Ge-107, which showed IC50 values of 60 and 100 micrograms/ml, respectively, for dipeptidylcarboxypeptidase from the longitudinal muscle layer. They also exhibited inhibitory activity against aminopeptidase from human CSF, the IC50 values being 450 and 440 micrograms/ml, respectively. Furthermore, these compounds showed inhibition of dipeptidylaminopeptidase from monkey brain and the longitudinal muscle layer of bovine small intestine. These compounds are expected to have analgesic effects due to their inhibition of the degradation of endogenous opioid peptides.
A collimated germanium detector with an energy resolution of 1 keV full width at half maximum at 140 keV was used to measure the energy spectrum of radiation emitted from a test object containing an asymmetric distribution of 99mTc and nonuniform attenuation. Energy spectra were recorded from 24 positions around the object and convolved with Gaussian functions to simulate data that would have been acquired with a scintillation camera. The scatter fraction was computed from the convolved spectra in conjunction with a scatter-free reference spectrum. After adding appropriate Poisson noise, a technique based on maximizing the signal to noise ratio was developed to optimally subtract the scatter fraction from the recorded counts. SPECT imaging of the test object was performed to evaluate the correction technique.
The effects of two novel organic germanium compounds, 1-phenyl-2-carbamoylethylgermanium sesquisulfide (PCAGeS) and 1-phenyl-2-carbamoylethylgermanium sequioxide (PCAGeO), on transplantable murine tumors and immune responses were studied. Both drugs showed low toxicity for mice. In culture, neither substance displayed significant cytotoxicity against murine tumor cells L1210 leukemia, L5178Y lymphoma, or IMC carcinoma. Growth of subcutaneously transplanted IMC carcinoma or Meth-A fibrosarcoma was markedly reduced by oral administration of PCAGeS. PCAGeO exhibited a similar but smaller effect on the tumor growth. Pulmonary metastasis of Lewis lung carcinoma was inhibited by oral or intraperitoneal treatment with PCAGeS. The activity of cyclophosphamide or Adriamycin against L1210 leukemia was significantly potentiated by oral administration of PCAGeS. PCAGeS enhanced the delayed-type hypersensitivity response to sheep red blood cells (SRBC) of mice or restored the response suppressed by ascitic IMC carcinoma, but did not significantly affect the formation of antibody to SRBC. PCAGeO similarly stimulated the DTH reaction. Phagocytic activity of peritoneal macrophages was enhanced by oral treatment of mice with PCAGeS. The results suggest that PCAGeS and PCAGeO display tumor-inhibitory activity by modification of the immune mechanism.
The antitumor effect of an organic germanium compound, carboxyethylgermanium sesquioxide (Ge-132), was examined in mice using two systems: one, the ascitic form of Ehrlich carcinoma in DDI mice, and the other, the solid form of Meth-A fibrosarcoma in BALB/c mice. In the mice with Ehrlich ascitic tumors, a remarkable prolongation in life span was observed after intraperitoneal (i.p.) or per oral (p.o.) administration of Ge-132 (300 mg/kg), but not after intravenous (i.v.) injection of the same compound. Following i.p. or p.o. administration, cytotoxic macrophages (Mø) were induced in the peritoneal cavity after 48 h. although this was not the case after i.v. injections. When the in vivo effect of these in vitro active Mø was examined after adoptive transfer to mice bearing Ehrlich ascitic tumor cells, a significant antitumor effect was noted. In the mice bearing solid Meth-A tumors, i.v. injections of Ge-132 (100 mg/kg) were found to inhibit tumor growth remarkably, although i.p. and p.o. administrations did not have the same result. This inhibitory effect of Ge-132 by i.v. administration was explained by the continued augmentation of NK activity in peripheral blood, which was followed by the induction of specific killer cells appearing in the spleen. When the mice which had recovered from Meth-A tumor growth, following i.v. injections of Ge-132, were challenged with the same tumor on day 30, all mice were able to tolerate the challenge, but not a challenge of RL male 1 tumor cells. These observations may indicate that the differing antitumor effects of Ge-132 produced when different administration methods are used can be explained by the variation in effector cells induced by such different administration routes.
After oral administration of an organic germanium compound, Ge-132 (300 mg/kg), a significant level of interferon (IFN) activity was detected in the sera of mice at 20 hr and it reached a maximum of 320 U/ml at 24 hr. This IFN activity was lost after heat- or acid-treatment, suggesting that the induced IFN is of gamma nature. The molecular weight of this IFN was estimated to be 19,000 daltons by gel filtration. After the oral administration of Ge-132, NK activity of spleen cells had increased at 24 hr and cytotoxic macrophages were induced in the peritoneal cavity at 48 hr. In mice, receiving intraperitoneal (i.p.) injections of trypan blue or carrageenan 2 days before oral administration of Ge-132, neither induction of IFN nor augmentation of NK activity followed. X ray irradiation of mice also rendered the mice incapable of producing IFN, all suggesting that both macrophages and lymphocytes are required for this IFN induction. After i.p. administration of induced IFN, both NK and cytotoxic macrophage activities appeared at 48 hr with as little as 20 U/ml titered IFN. These facts may indicate that the augmentation of NK and activation of macrophages in mice after oral administration of Ge-132 is mediated by induced IFN.
A Monte Carlo program was developed which determines the energy response of X-ray detectors of various "nested" sizes simultaneously. Twenty-one planar germanium detectors with cylindrical crystals were chosen, which are commercially available for X-ray spectrometry. The photopeak efficiency, K alpha and K beta escape fractions. Compton fraction, elastic fraction, penetration fraction, and the Compton continuum were tabulated as a function of incident X-ray energies from 12 to 300 keV in 2-keV increments. Coefficients of polynomials fitted to the Compton continua were also calculated to facilitate computer implementation of spectrum corrections. Spectrum correction methods which use the Compton continua determined by Monte Carlo calculation were compared with those approximated by rectangles. Comparison of the residual root-mean-square (RRMS) values between the incident and corrected spectra showed that the former method yielded lower RRMS values. However, the differences in these values are small, indicating that the simple rectangular approximation may be adequate for most spectral measurements.
A new stationary 200-element ultrapure germanium (HPGe) array has been tested for accuracy and sensitivity in quantitating the distributed concentration of single-gamma-emitting radionuclides in phantoms approximating the size of the human brain. The phantoms consisted of 42 blocks of 39.1 cm3 average volume. Fourteen different permutations were studied. The concentrations in the blocks varied from 0i to 4.64 muCi/cm3. This first-generation instrument makes it possible to reconstruct the distributed concentration with a mean relative error of 8.3% at 200,000 counts per sample (1,000 counts/detector), and has sensitivities of 6,200 and 12,000 cps, respectively, for 1 muCi/cm3 of Xe-133 and Tc-99. The reconstruction algorithm is based on the conjugate gradient method of solving the set of linear equations that account for geometric, attenuation, and scatter factors. The results have implications for measuring the distribution of the partition coefficients, blood flow, blood volume, and concentration of tracers emitting single gamma photons in 42 anatomic subvolumes (30 cm3 average) of the entire brain simultaneously.
We studied DMH induced colon cancer in 120 wistar rats, which were divided into 8 groups based on different diets. They were killed and autopsied on 4 weeks after the last injection of DMH. The tumors in various organs including its characteristics, number, site, histological types and ultrastructural changes were observed. The results showed that high fat diet has a significant effect on DMH induced colon cancer. Selenium and calcium can inhibit the effect of DMH and decrease the incidence of colon cancer. Selenium can also interfere the effect of high fat diet but germanium has no effect on colon carcinogenesis.
The anticarcinogenic effects of bioginseng and two germanium-selective drugs produced by cultivating cells of ginseng radix (Panax ginseng C. A. Mey) in a conventional medium or in media containing organogermanium compounds were studied. Squamous-cell carcinomas of the uterus cervix and vagina were induced by intravaginal applications of 7,12-dimethylbenz(a)anthracene in mice. The drugs of ginseng were used orally or intravaginally during a long period of time of the postinitiation stage of carcinogenesis. All the drugs used locally effectively inhibited the development of induced carcinomas of the uterus cervix and vagina. When orally used, the drugs of ginseng exhibited only an insignificant tendency to inhibit the carcinogenesis of uterus cervix and vagina. The anticarcinogenic effects of the compared drugs were similar.
N-Methyl-N'-nitrosoguanidine (MNNG) was administered (100 mg/L) in drinking water in 100 Wistar rats for 24 weeks to induce the precancerous lesion in glandular stomach. 77 rats with the precancerous lesion in glandular stomach were divided into 3 groups randomly at the 25 thweek. Yeast selenium (Yse, 4 mg/L) and carboxyethyl germanium sesquioxide (Ge-132, 600 mg/L) in drinking water were administered respectively in the corresponding treatment groups: 100 ml/MNNG in drinking water was administered in the treatment group, and 100 ml/MNN in drinking water was administered in the treatment group and control group for another 5 weeks. The experiment ended at the end of the 37th week. The results showed that the incidence of glandular stomach cancer in the Yse group was significantly lower than that in the control group; the infiltrating depth of glandular stomach cancer in the Yse group and the Ge-132 group was remarkably shallower than that in the control group. These findings suggest that Yse and Ge-132 have some preventive effect on the precancerous lesion in rat glandular stomach induced by MNNG.
A germanium-gallium generator producing EDTA-free Ga-68 would permit the synthesis of a broad range of Ga-68 radiopharmaceuticals and thus facilitate the widespread application of positron tomography. We have investigated a solvent-extraction generator system producing the weak complex of Ga-68 with 8-hydroxyquinoline (Ga-68 oxine), free of EDTA. The conditions for optimum Ga-68 yield and minimum Ge-68 breakthrough involve extraction with chloroform from pH 5 buffer containing Ge4+ carrier, followed by evaporation to dryness. This produces Ga-68 yields of 70--80%, with Ge-68 breakthrough of less than 0.003%. The Ga-68 oxine is readily converted to other radiopharmaceuticals such as Ga-68 EDTA, Ga-68 EDTMP, or Ga-68 colloid, and is conveniently delivered dry. The extraction system is simple and amenable to automation, and the low loss rate and 280-day half-life of Ge-68 provide a generator with a long useful lifetime.