Persistent Primary Cytomegalovirus Infection After Deceased Donor Kidney Transplant: Ganciclovir Susceptibility of Human Cytomegalovirus With UL97 D605E Mutation: A Case Report

BACKGROUND

Cytomegalovirus (CMV) could cause rejection in immunocompromised patients during early post-renal transplant stage. The American Transplant Society guidelines recommend prophylactic therapy with ganciclovir (GCV) for 3 to 6 months to prevent CMV infections in adult renal transplant patients. However, there is no recommended CMV treatment regimen for pediatric patients.

MAIN FINDINGS

We performed deceased donor kidney transplant from an anti-CMV antibody-positive donor to an anti-CMV antibody-negative 15-year-old female recipient with end-stage renal disease caused by bilateral renal hypoplasia. One month after transplant, increase in positive cells in the CMV antigenemia assay indicated a primary CMV infection in the patient, who immediately received GCV. She was switched to foscarnet after 4 months of anti-CMV therapy because of clinical GCV resistance. CMV was isolated from the peripheral blood mononuclear cells but neutralizing antibody was not detected. Isolated CMV was susceptible to GCV and foscarnet, although it carried the UL97 D605E mutation, assumed to be associated with GCV resistance.

CONCLUSIONS

The primary CMV infection presented a phenotypic clinical drug resistance, but all recovered CMV isolates were drug-susceptible even if isolated after prolonged anti-CMV therapy, indicating that immune status was more important for recovery from primary CMV infection than anti-CMV therapy.

Rhazinilam and quebrachamine derivatives from Yunnan Kopsia arborea

Three new rhazinilam-derived alkaloids, kopsiyunnanines C1, C2, and C3, and a new quebrachamine-type alkaloid, kopsiyunnanine D, which possess an unusual methoxymethyl or ethoxymethyl function, were isolated from the aerial parts of Yunnan Kopsia arborea. This is the first report of the presence of these functions in natural alkaloids. The structures and absolute configurations of the alkaloids were determined by spectroscopic methods and confirmed by semisynthesis.

Age related elevation of serum macrophage colony stimulating factor (M-CSF) level

We recently reported that the serum level of macrophage colony-stimulating factor (M-CSF) was elevated in patients with cerebral infarction. In the present study, we measured serum M-CSF level, as well as coagulo-fibrinolytic markers and general laboratory tests in adult healthy subjects of various ages, and investigated the relationship between age and M-CSF level. M-CSF in aged subjects (>or=65 years of age) was significantly higher than that in the younger subjects (<65 years of age), and a significant positive correlation between age and M-CSF was found. Significant positive correlations between M-CSF, and plasma levels of thrombomodulin (TM), von Willebrand factor antigen (vWF), thrombin-antithrombin III complex (TAT), prothrombin fragment 1+2 (F1+2), d-dimer products cross-linked fibrin degradation products (d-dimer) and plasmin-antiplasmin complex (PAP) were also found. Among the general laboratory tests, there was only a significant correlation between M-CSF and serum creatinine; however, no significant correlation was found between M-CSF and other tests including blood cell counts. From these results, age-related elevation of serum M-CSF level was confirmed, and was suggested not to indicate the alteration of hemopoietic condition in aged subjects but to be related to thrombotic state or systemic damaged blood vessel in the apparently healthy aged people.

Analyses of serum lipoprotein(a) and the relation to phenotypes and genotypes of apolipoprotein(a) in type 2 diabetic patients with retinopathy

To elucidate the association of lipoprotein(a) (Lp(a)) with diabetic retinopathy (DR), we studied the serum Lp(a) concentrations (n = 412), apolipoprotein(a) (apo(a)) phenotypes expressed by the number of kringle 4 (K4) repeats (n = 150), apo(a) gene genotypes (n = 161) of type 2 diabetes with or without DR. The 5'-untranslated region of apo(a) gene was classified into seven haplotypes (A to G) and 18 genotypes by PCR-RFLP at three distinct sites. The serum Lp(a) concentrations were significantly higher in diabetic patients than in normal controls. Furthermore, the patients with DR, especially proliferative retinopathy showed higher serum Lp(a) concentrations than those without DR. Although a negative correlation was found between the serum Lp(a) concentrations and the number of K4 repeats in total diabetic patients, no difference was seen in the distribution of the number of K4 repeats between those with and without DR. In the same apo(a) phenotypes, the patients with DR had higher Lp(a) concentrations than those without DR. Among the genotypes, type CC showed significantly higher serum Lp(a) concentrations than the other genotypes. However, there was no difference in the ratios of the type CC between the patients with and without DR. In conclusion, other factors than phenotypes and genotypes in the 5'-untranslated region of apo(a) may be responsible for the elevation of serum Lp(a) in diabetic patients with retinopathy.

Increased levels of serum tissue inhibitor of metalloproteinase-1 but not metalloproteinase-3 in atopic dermatitis

Matrix metalloproteinases and their specific inhibitors, tissue inhibitors of metalloproteinases (TIMPs), contribute to inflammation-induced tissue destruction and subsequent remodeling for maintenance of tissue homeostasis. Since the production of these enzymes and their inhibitors is regulated by mediators such as proinflammatory cytokines and growth factors, elevated levels of serum TIMPs and/or MMPs have been documented in patients with several inflammatory disorders. In this study, we examined the role of TIMPs and MMPs in the pathogenesis of atopic dermatitis (AD) by evaluating the serum levels of TIMP-1 and MMP-3 in 40 patients with AD and 20 control subjects by ELISA. The serum TIMP-1 levels were significantly higher in AD patients in exacerbation status than in nonatopic subjects, whereas serum MMP-3 levels were not significantly different between them. As a result, AD patients revealed significantly elevated TIMP-1/MMP-3 ratios. The levels of serum TIMP-1 were significantly reduced in AD patients following conventional treatments. Significantly higher values of peripheral eosinophil counts, serum levels of IgE and lactate dehydrogenase, eruption score, and eruption area were noted in the AD patients with elevated TIMP-1 levels when compared with those with normal values. Moreover, the points of chronic eruptions such as lichenification and prurigo were significantly higher in the patients with elevated TIMP-1 levels than those with normal TIMP-1, while those of acute lesions such as oozy/microvesicles and oedema were not different between these groups. Serum TIMP-1 level may be a useful marker to estimate the long-term disease activity of AD.

[Historical review on chemical and medical studies of globefish toxin before World War II]

"Fugu," a species of globefish has eaten by Japanese people for a long time, so globefish poisoning in Japan has been prevalent. Figures are shown in the Annual Food Poisoning Report collected and issued by health service authorities of Japanese Government since 1879. These reports prompted Dr. Yoshizumi Tahara, National Institute of Hygienic Sciences to conduct a chemical investigation of the toxic substance of globefish in 1884. However, the analysis was very difficult and his report of investigation was delayed. Before publication of the report of Dr. Tahara, pharmacological and toxicological studies of globefish poisoning were reported by three research groups from the Facultly of Medicine, University of Tokyo in 1889. These reports concluded that globefish poison has curare-like activity and its distribution was limited to specific organs such as the ovaries and the liver. Dr. Tahara successfully isolated the poison from aqueaous extract of ovaries of globefish by precipitation with lead acetate in the presence of ammonia. He presented the results at the monthly meeting of the Pharmaceutical Society of Japan in July 1894. He continued the studies and established an improved method for extraction and purification suitable for large-scale production. Finally, he confirmed that globefish contains only one toxic substance and named it Tetrodotoxin (TTX) in 1909. He elucidated the chemical nature of TTX as follows: 1) TTX is an amorphous hygroscopic powder and its character is neither alkaloid nor protein. 2) The possibility of TTX being a protamine was excluded by chemical analysis. Before the discovery ot TTX, according to folklore, globefish was regarded as medicine for leprosy because flesh of globefish contaminated with a sublethal dose of toxic substance alleviated the neuralgia of patients affected with leprosy. The clinical effect of TTX prepared by Tahara's method to suppress severe neuralgia due to leprosy and to reduce muscle spasms due to tetanus were reported by dermatologists in 1911. TTX was also given to patients with rheumatoid arthritis due to its analgesic effect. Thus, injectable TTX was manufactured and distributed by Sankyo Co., Ltd. from 1913. In terms of purity, the TTX preparation manufactured by Tahara's method seemed to be much more crude than the crystalline TTX obtained by Professor Tsuda and Dr. Kawamura in 1952. According to their report, the LD50 of the preparation for clinical use manufactured by Tahara's method was 4-5 mg/kg mouse compared to 4-6 microg/kg mouse of crystalline TTX.

[Historical review of insulin and its preparations in pharmacopoeia (3). Fish insulins]

Existence of encapsulated glands situated in the mesentery of certain teleosti was reported by Brockmann (1846) and Stannius (1848), respectively. Thus the gland was named stannius corpuscle or Brockmann body. Later, as results of histological study, cells of stannius corpuscle tissues were constituted with Langerhans islet cells observed in mammalian pancreas by Diammare (1899) and Laguesse (1906). Thus, before the days of discovery of insulin by Banting and Best in 1921, stannius corpuscle has been interesting from the aspects of comparative anatomy and physiology. Rennie (1906) examined a large number of specimens in various species of teleosti and gave the term "principal islet" to easily recognizable stannius corpuscle. Osawa studied comparative anatomy in Freiburg and returned to Tokyo. He continued the study of comparative anatomy of Langerhans islet aand published a report on observation of "principal islet" of flatfish, limanda yokohamae Gth. in 1912 in Japanese. His report seemed to be a milestone of studies of fish insulin in Japan. Macleod attempted to demonstrate direct evidence on secretion of insulin from Langerhans islet cells. Experiments were made on extraction of "principal islet" of teleosti, angler Lophius) and sculpin (Myoxocephalus) to obtain insulin and demonstrated activity. No insulin activity was obtained from pancreatic tissues constituted with acinar cells of these fishes. In the case of elasmobranch, Langerhans islets are not separated, but potent insulin could be extracted from the pancreas. His report published in 1922 was the first report on fish insulin. Succeeding to Macleod's report, several reports on fish insulin were contnributed from Canada, England and U.S.A. until 1929. Dr. Kkumagai, Professor of Internal Medicine, Tohoku Imperial University (Sendai) also conducted the studies on extraction of active principle of pancreas since 1920, independently. But, a Toronto group reached the goal on discovery of insulin earlier than the Sendai group. The Sendai group also described extraction of active principle from the "principal islet" of teleosti. Especially, Ukai (1926) described morphological study on pancreas and stannius corpuscle for more than twenty species of fish. His report played an important role as the next milestone on the road of fish insulin development studies in Japan. In 1926, Dr. Sakaguchi who was a leading clinical diabetologist in Japan published a monograph entitled "Insulin" written in Japanese. He referred the report on fish insulins of McCormick and Noble and Dr. Kumagai's report, however, he commented that production of insulin from fish seemed to be less worthy due to requirements of laborious work to collect small stannius corpuscle from fish. Professor A. Ogata described a textbook entitled "Zoki-Yakuhin-Kagaku (chemistry of organotherapeutics): in 1931. In the first edition, papers of Macleod, McCormick, Dudley and Osawa were referred. In the revised fifth edition (1940) contained description of unpublished data of insulin content of various kinds of fish caught in Japan and supplied from his student Nagasawa. Under the circumstance of expanding tendency of the China Incident to World War II, shortage of importation and production of insulin preparations manufactured from domestic animals was anticipated. Development on manufacture of fish insulin became urgent. [Truncated]

Soluble CD30 is more relevant to disease activity of atopic dermatitis than soluble CD26

It is suggested that CD30 and CD26 are surface molecules expressed on activated Th2 and Th1 cells, respectively. We examined plasma levels of soluble CD26 (sCD26) and sCD30 in patients with atopic dermatitis (AD) when their eruptions were aggravated and in non-atopic healthy controls, and then analysed the possible correlation between these values and the levels of several clinical markers. The plasma levels of both sCD30 and sCD26 were significantly higher in AD patients than in controls, both in exacerbation status and after conventional treatment. Multiple regression analyses showed that plasma sCD30 was a much better predictor of the levels of serum IgE, serum LDH and plasma sCD25, and the area and the score of AD eruption than sCD26, although elevated levels of both sCD30 and sCD26 are associated with these clinical predictors of AD. Importantly, sCD30 plasma levels decreased significantly in AD patients after conventional treatment, while no significant transition was noted in the concentration of sCD26. Moreover, a significant reduction of sCD30 levels was observed in the group of patients whose eruption score was reduced > 50%, whereas it was not in those < 50%. These findings provide evidence that the successful treatment of AD is associated with down-activation of Th2.

Etiologic factors in femoral head osteonecrosis in growing rats

Osteonecrosis of the epiphyseal nucleus of the femoral head, which resembles that in Perthes' disease in children, was studied in spontaneously hypertensive rats (SHRs) and ordinary Wistar Kyoto rats (WKYs). The SHRs were kept in ordinary cages and the WKYs in custom-made high cages from 5 weeks to 15 weeks after birth. The WKYs had to stand on their hind limbs to feed because the feed box and the drinking aperture were placed at a high level. At 15 weeks, the femurs were resected and examined radiographically and histologically. There was a relatively high incidence of avascular necrosis in the epiphyseal nuclei of the femoral heads; 45.8% in SHRs and 33.3% in WKYs. In the SHRs, there were ossification disturbances of the proximal femoral epiphysis and deformities of the proximal femurs, such as a flattened femoral head and short neck. These findings suggest that constitutional cartilage disorder in the SHRs and excessive mechanical stress on the femoral heads in the WKYs participated in the etiology of the osteonecrosis.

Dopamine D4/D2 receptor selectivity is determined by A divergent aromatic microdomain contained within the second, third, and seventh membrane-spanning segments

Conserved features of the sequences of dopamine receptors and of homologous G-protein-coupled receptors point to regions, and amino acid residues within these regions, that contribute to their ligand binding sites. Differences in binding specificities among the catecholamine receptors, however, must stem from their nonconserved residues. Using the substituted-cysteine accessibility method, we have identified the residues that form the surface of the water-accessible binding-site crevice in the dopamine D2 receptor. Of approximately 80 membrane-spanning residues that differ between the D2 and D4 receptors, only 20 were found to be accessible, and 6 of these 20 are conservative aliphatic substitutions. In a D2 receptor background, we mutated the 14 accessible, nonconserved residues, individually or in combinations, to the aligned residues in the D4 receptor. We also made the reciprocal mutations in a D4 receptor background. The combined substitution of four to six of these residues was sufficient to switch the affinity of the receptors for several chemically distinct D4-selective antagonists by three orders of magnitude in both directions (D2- to D4-like and D4- to D2-like). The mutated residues are in the second, third, and seventh membrane-spanning segments (M2, M3, M7) and form a cluster in the binding-site crevice. Mutation of a single residue in this cluster in M2 was sufficient to increase the affinity for clozapine to D4-like levels. We can rationalize the data in terms of a set of chemical moieties in the ligands interacting with a divergent aromatic microdomain in M2-M3-M7 of the D2 and D4 receptors.

Plummer's disease with spontaneous progression to hypothyroidism

A case of Plummer's disease that spontaneously progressed to hypothyroidism is presented. A 49-year-old female visited our hospital because of a 3 kg decrease in body weight during the previous month and a painless nodule in the right anterior area of her neck. A diagnosis of Plummer's disease was made based on the results of thyroid function tests, thyroid scintigrams, and an ultrasonogram, but the patient's disease followed an usual clinical course. About two months later, she gradually developed manifestations of permanent hypothyroidism, and anti-thyroid autoantibodies became positive. In spite of continuous administration of levothyroxine sodium, uptake of 99mTcO4- to the nodule was unchanged or rather increased according to the consecutive thyroid scintigraphies. These results suggested that this case represented an autonomously functioning nodule with underlying silent thyroiditis and Hashimoto's disease.

Evoked spinal cord potential monitoring reveals peroneal nerve ischemia during thoracoabdominal repair: a case report

An 82-year-old man underwent thoracoabdominal aortic replacement under cardiopulmonary bypass with left femoral artery cannulation. Lumber descending evoked spinal cord potentials and segmental evoked spinal cord potentials were monitored simultaneously for detecting spinal cord damage. When the cardiopulmonary bypass was terminated, a peripheral nerve ischemia pattern was evident. Left peroneal nerve paralysis was present at emergence from anesthesia. This monitoring system revealed that peroneal nerve paralysis can occur due to leg ischemia caused by femoral artery cannulation. This is, to our knowledge, the first report that segmental evoked spinal cord potential monitoring reveals peroneal nerve ischemia during thoracoabdominal surgery.

Generalized dermal dysplasia and perifollicular mucinosis in a dog

Multiple nodules 0.5-2 cm in diameter were observed in the dorsal skin of a 1.5-year-old male castrated mongrel dog. Histopathologically, perifollicular mucinosis and clusters of small cells with a dense, round nucleus and scant cytoplasm were seen. The small cell clusters were present in the dermis near the epidermal basal layer or surrounding hair follicles. These cells demonstrated different staining patterns for vimentin and keratin depending on their location; ultrastructurally, they were poor in organelles and connected to each other with cytoplasmic projections. These findings suggested that they were immature epithelial cells. The case was diagnosed as generalized dermal dysplasia and perifollicular mucinosis.

In vivo biodistribution of a radiotracer for imaging serotonin-1A receptor sites with PET:[11C]LY274601

LY274601 [R-(+)8-thiomethyl-2-(di-n-propyl-amino)tetralin], a full agonist of the 5-HT1A receptor with high affinity and selectivity, was labeled with 11C and 3H, and its in vivo behavior was studied to evaluate [11C]LY274601 as a PET radiotracer for imaging 5-HT1A receptor sites in living brain. Following intravenous tail injection into mice, [11C]LY274601 showed high blood-brain barrier permeability and accumulated in regions known to have high densities of 5-HT1A receptor sites such as the brain stem including the raphe nuclei. The binding of the radiotracer in target tissues is blocked by pre-injection of the 5-HT1A receptor selective ligand 8-OH-DPAT (1 mg/kg, s.c.), suggesting that the binding is specific to 5-HT1A receptor sites. Using ex vivo autoradiography, the target tissues such as hippocampus CA1-4 fields, piriform cortex, dorsal raphe nucleus and lateral septum were visualized as hot spots. These tissues were observed to have binding 2-2.7 times greater than the cerebellum. The distribution of the radiotracer agrees well with the distribution of 5-HT1A receptors revealed by in vitro autoradiography with [3H]8-OH-DPAT. However, the radiotracer was metabolized quickly and cleared from target tissues with a half life of approximately 15 min. [11C]LY274601 showed high non-specific binding in regions with low number of 5-HT1A receptor sites such as cerebellum.

Age-related augmentation of stroke tendency evaluated using plasma P-selectin levels

Plasma soluble P-selectin is thought to be a useful marker for thrombotic diseases. To evaluate the thrombotic state and risk of stroke in aged healthy subjects, we investigated plasma P-selectin levels in healthy subjects and ischemic stroke patients. Plasma P-selectin was measured in 67 healthy subjects and 35 aged (>or= 65 years of age) patients with chronic ischemic stroke using a sandwich enzyme-linked immunosorbent assay (ELISA). Plasma P-selectin was significantly higher in aged (>or= 65 years of age) healthy subjects than in young (< 65 years of age) healthy subjects. Significant difference did not exist between aged healthy subjects and aged stroke patients who were not receiving anti-platelet agents. Anti-platelet agent had no significant effect on plasma P-selectin levels in aged stroke patients. The amounts of P-selectin released from platelets into the plasma after stimulation with adenosin diphosphate in young and aged healthy subjects were not significantly different. Elevated levels of P-selectin in aged healthy subjects suggests the existence of a subclinical thrombotic state which can result in a stroke. Elevated P-selectin levels are not thought to be due to platelet hyperfunction.

Radiosynthesis and biodistribution of the S-[18F]fluoroethyl analog of McN5652

[11C]McN5652 has been reported to exhibit favorable properties as a PET radiotracer for studying serotonin uptake sites. However, the use of this radiotracer may be limited by the short half-life of11C. To obtain a tracer with longer physical half-life, we have synthesized the S-[18F]fluoroethyl analog of McN5652 (trans-1,2,3,5,6,10b-hexahydro-6-[4-([18F]fluoroethylthio)-phenyl] pyrrolo-[2,1-a]-isoquinoline) ([18F]FEMcN) and evaluated as a PET radiotracer for imaging serotonin uptake sites. The radiosynthesis was performed via a one-pot, two-step procedure. In the first step, 1-bromo-2-[18F]fluoroethane was prepared from 2-bromoethyl triflate and K18F/Kryptofix 2.2.2. in THF at room temperature. The second step, the S-fluoroalkylation of the normethyl McN5652, a thiol, was carried out, without isolating the 1-bromo-2-[18F]fluoroethane, by adding the normethyl McN5652 to the reaction vial, which was warmed at 45 degrees C for 1 min. The fluoroalkylation reaction proceeded quickly, giving [18F]FEMcN in an average overall radio-chemical yield of 13 +/- 7%. The specific activity was 1593 +/- 625 mCi/mumol. Ex vivo autoradiographic studies revealed that [18F]FEMcN accumulated into regions with high densities of 5-HT uptake sites such as hypothalamus, substantia nigra, and raphe nuclei. With blockade by nitroquipazine, a selective and highly potent 5-HT uptake blocker, the activity level in these regions was close to that in regions low in 5-HT uptake sites such as cerebellum, suggesting that this radiotracer binds specifically to 5-HT uptake sites. The regional distribution of [18F]FEMcN at 60 min postinjection correlated with the distribution of [11C]McN5652 reported in the literature. The specific binding of this radiotracer determined as the difference in radioactivity accumulation with and without blocking by the 5-HT uptake blocker agreed with the distribution of the number of 5-HT uptake sites measured in vitro. Thus, 5-HT uptake sites were visualized in vivo with [18F]FEMcN. However, comparison with the in vivo behavior of [11C]McN5652 indicated less favorable properties of [18F]FEMcN as a PET radiotracer for imaging 5-HT uptake sites, including lower blood-brain barrier penetration and lower target-to-nontarget ratios.

Occurrence of Graves' disease during retreatment with interferon-alpha 2a for chronic hepatitis C

The present report describes a patient who developed Graves' disease 3 months after inception of retreatment with higher doses of interferon-alpha 2a for chronic hepatitis C, although the initial 6-month treatment caused no serious adverse reactions. Severe hyperthyroidism continued despite discontinuation of interferon-alpha 2a, and the patient was subsequently treated with 131I. This case suggests careful evaluation of the safety of retreatment to prevent manifestation of such a complication in the retreatment of chronic hepatitis C with interferon.

Positron emission tomography of 5-HT transporter sites in the baboon brain with [11C]McN5652

[11C]McN5652 is a new radioligand specific for 5-hydroxytryptamine (5-HT; serotonin) transporters. In this study we used [11C]McN5652 to image the 5-HT transporter sites in baboon brain by positron emission tomography (PET). Dynamic PET studies were performed in three Papio anubis baboons. The animals were injected intravenously first with 11C-labeled (+)-McN5652([11C](+)McN5652), then with pharmacologically inactive enantiomer 11C-labeled (-)-McN5652 ([11C](-)McN5652); two animals received a third study with [11C](+)McN5652 after pretreatment with the specific 5-HT uptake site inhibitor fluoxetine (5 mg/kg). Initial uptake into the brain was similar for both [11C](+)McN5652 and [11C](-)McN5652. At later times (45-120 min after injection), only [11C](+)McN5652 showed a distribution characteristic for 5-HT uptake sites. In contrast, in studies with [11C](-)McN5652 and in those with [11C](+)McN5652 after 5-HT uptake site blockade with fluoxetine, 11C radioactivity concentrations were significantly lower and the distribution pattern was relatively even. The differences between [11C](+)-and (-)McN5652 were calculated for the time interval 95-125 min postinjection and used to estimate specific binding. Specific binding correlated well (r = 0.95, p < 0.001) with the known density of 5-HT uptake sites in human brain. These results indicate that [11C](+)McN5652 is suitable for PET imaging of 5-HT uptake sites in primate brain.

Positron emission tomography imaging of serotonin transporters in the human brain using [11C](+)McN5652

This paper presents the first Positron Emission Tomography (PET) images of the serotonin (5-hydroxytryptamine, 5-HT) transporter in the living human brain. PET imaging was performed in three healthy subjects after administration of [11C](+)McN5652 (the (+) enantiomer of trans-1,2,3,5,6,10 beta-hexahydro- 6-[4-(methylthio) phenyl]pyrrolo-[2,1-a] -isoquinolone), a radioligand previously shown to selectively label the 5-HT transporter in vivo in the mammalian (mouse and baboon) brain. To demonstrate the specificity of [11C](+)McN5652 binding, additional images were obtained in the same subjects after injection of [11C](-)McN5652, the pharmacologically inactive enantiomer, and, in two of the subjects, with [11C](+)McN5652 after pretreatment with the 5-HT uptake site blocker fluoxetine. Highest accumulation of [11C](+)McN5652 was observed in the midbrain, putamen, caudate nucleus, hypothalamus, and thalamus, regions known to contain high densities of 5-HT transporters. In these areas [11C](+)McN5652 concentrations rose steadily over 120 min. In contrast, with [11C](-)McN5652 and when the [11C](+)McN5652 binding was inhibited with fluoxetine, radioactivity concentrations declined after reaching a maximum (at 20 to 30 min). Inhibition studies with fluoxetine suggest that only with [11C](+)McN5652, there is specific binding. In the cerebellum, a region relatively void of 5-HT transporters, both [11C](+)McN5652 with and without fluoxetine block and [11C](-)McN5652 were released at approximately the same rate. The results of the studies indicate that [11C](+)McN5652 labels 5-HT transporter sites in the human brain. Quantitative PET imaging studies with this new tracer should provide valuable information on the status of these sites in health and disease.

An improved method for the synthesis of radiolabeled McN5652 via thioester precursors

An improved procedure that facilitates routine production and increases the radiochemical yield of [11C]McN5652 (trans-1,2,3,5,6,10b-hexahydro-6-[4-([11C]methylthio)-phenyl]pyrrolo- [2,1-alpha]-isoquinoline) is presented. Specifically, thiol acetate, butyrate, and benzoate derivatives of McN5652 were prepared as the precursors for the [11C]McN5652 synthesis. These thioesters offer greater stability than the previously used thiol precursor (desmethyl McN5652) and enable a single batch of material to be used for multiple radiolabelings. Hydrolysis of the thioester functionality (tetrabutylammonium hydroxide, 10 min) unmasked the free thiol which, without purification, was reacted with [11C]iodomethane in DMF at 40-45 degrees C for 1 min. The average decay-corrected radiochemical yield for [11C]McN5652 was 26% with an average specific activity of 2290 mCi/mumol (end of synthesis). This facile radiolabeling method, utilizing the butyrate thioester of McN5652, was also employed in the preparation of [3H](+)- and (-)McN5652 [trans-1,2,3,5,6S (or 6R),10bR, (or 10bS)-hexahydro-6-[4-([3H]methylthio)phenyl]pyrrolo-[2,1,alpha]- isoquinoline] from [3H]iodomethane.

Highly potent indanamine serotonin uptake blockers as radiotracers for imaging serotonin uptake sites

Two highly potent indanamine serotonin (5-HT) uptake blockers, trans-3'-(4'-bromophenyl)-1-indanamine (trans-[11C]DBPI or [11C]Lu 19-056) and its iodo analog, trans-3'(4'-[125I]iodophenyl)-1-indanamine (trans-[125I]DIPI) were evaluated as radiotracers for imaging 5-HT uptake sites in vivo Trans-[11C]DBPI was synthesized by N-methylation of the normethyl precursor with [11C]iodomethane. Trans-[125I]DIPI was synthesized by iododestannylation of the tributyltin precursor with [125I]NaI. Radiochemical yields for the [11C] and [125I] radiotracers were 34 and 40% with specific activities of 4000 and 1800 mCi/mumol, respectively. In vitro, the iodo analog, trans-DIPI, showed an IC50 value of 0.26 nM in inhibition of [3H]paroxetine binding to 5-HT uptake sites in rat cortex. The potency was found to be equivalent to that of paroxetine or McN5652. In vivo, after i.v. injection into mice, both radiotracers showed high uptake in brain (3-4% dose/whole brain at 15 min) and high accumulation into target tissues such as hypothalamus and olfactory tubercles (7-8% dose/g at 60 min). The binding was blocked by pre-injection of 5 mg/kg of peroxetine. While the in vivo distribution agreed with previously reported 5-HT uptake site distribution, the radiotracers showed high uptake in non-target tissues such as cerebellum, resulting in low target-to-non-target ratios (1.5-1.6 at 60 min). Since washout from non-target regions was slower than from target regions, longer-time observation with 125I up to 6 h did not improve the ratios. HPLC analyses of mouse brain homogenates and blocking studies indicated that the high uptake in non-target regions is not the result of metabolism or any interaction of the radiotracers with those tissues via specific binding sites. In spite of low target-to-non-target ratios, target regions with high density of 5-HT uptake sites, such as the raphe nuclei, superior colliculi and substantia nigra, were visualized with trans-[125I]DIPI by ex vivo autoradiography, since the radiotracer showed high specific binding (total mimus nonspecific binding).

Circulating forms of immunoreactive parathyroid hormone-related protein for identifying patients with humoral hypercalcemia of malignancy: a comparative study with C-terminal(109-141)- and N-terminal(1-86)-region-specific PTHrP radioassay

We evaluated the circulating forms of immunoreactive PTHrP in 115 healthy subjects and 122 patients with malignant diseases by using radioassay systems (RAS) specific for the C-terminal (109-141) fragment of PTHrP (C-RAS) and for the N-terminal(1-86) (N-RAS). PTHrP levels in healthy controls ranged from 1.5 to 38.2 (mean: 24.5) pmol/L with the C-RAS and from 0.9 to 2.5 (mean: 1.7) pmol/L with the N-RAS. The ratio of circulating N-terminal fragment (N) to C-terminal fragment (C) of PTHrP was calculated to be about 1: 14.4 in the healthy subjects. Of the 122 patients with malignant diseases, 40 (32.8%) had circulating PTHrP levels undetectable with the N-RAS, but only 11 (9.0%) patients had levels undetectable with the C-RAS. Of the former 122 patients, 41 (33.6%) had high PTHrP as determined with the C-RAS, and 10 (8.2%) had high PTHrP as determined with the N-RAS. The former of these included only 8 (19.5%) HHM patients, while the latter included 8 (80.0%) HHM patients. The circulating N to C ratio was about 1: 70.7 in the HHM patients. The N and C obtained with the different RASs showed a close correlation (r = 0.86). The values also showed a close correlation with serum Ca; r = 0.75 for C-RAS and r = 0.81 for N-RAS. In addition, the correlations between the PTHrP reading obtained with the different RASs and serum Cr were: r = 0.42 with C-RAS and r = 0.26 with N-RAS. The circulating form of immunoreactive PTHrP fragments is therefore comprised mainly of PTHrP(109-141). In contrast, circulating concentrations of the PTHrP(1-86) fragment are very low, but detection of the PTHrP(1-86) fragment with the N-RAS is a more useful indicator of HHM with fewer false positive results and is less likely to be influenced by renal function than the detection of the PTHrP(109-141) fragment with C-RAS.

Thyroid imaging in a typical case of acute suppurative thyroiditis with abscess formation due to infection from a persistent thyroglossal duct

The clinical evaluation of thyroid imaging with 99mTc, 201Tl, and 67Ga in the uncommon, but potentially serious, disorder of acute suppurative thyroiditis (AST) with abscess formation due to infection from a persistent thyroglossal duct is reported. The 99mTc image showed functioning areas of the diseased thyroid gland and the 201Tl image demonstrated abscess formation in the thyroid gland of this patient. In addition, marked 67Ga accumulation was demonstrated in a wide area covering not only the area of the thyroid gland involved, but also associated circumferential inflammatory lesions in a patient with AST. The net thyroid uptake of 67Ga at 72 hours was calculated to be 13.8% of the injected dose.

Development of PET/SPECT ligands for the serotonin transporter

There is a great need for PET and SPECT ligands with high affinity and selectivity for the serotonin uptake site. These imaging agents would be useful in screening human populations at risk (e.g., individuals exposed to neurotoxic amphetamines such as MDMA and fenfluramine). Moreover, these radioligands would allow the study of serotonergic function in the normal living human brain, and they also would be useful in the examination of altered serotonergic neurotransmission in diseases such as depression and obsessive-compulsive and other neuropsychiatric disorders. Over the past several years, a number of radioligands have been studied in several laboratories for their in vivo binding to 5-HT uptake sites. Although [3H]paroxetine showed promising binding characteristics, conversion of authentic paroxetine into a PET or SPECT tracer turned out to be difficult and has not been achieved yet. Analogs of paroxetine displayed considerable loss of binding affinity and were, therefore, not useful for imaging purposes. For [11C]fluoxetine, [11C]citalopram, and cis-[11C]DDPI, target-to-nontarget (hypothalamus-to-cerebellar) ratios remained less than 2.0:1 over a 90-min period after injection. The most promising PET agents identified today are [11C]RTI-55 and [11C]McN-5652-X. [11C]RTI-55 labels both 5-HT and DA uptake sites. [11C]McN-5652-X is highly selective for 5-HT uptake sites, and its distribution is consistent with the neuroanatomical distribution of the 5-HT uptake site. Because [11C]McN-5652-Z is a racemic mixture of two stereoisomers, of which the (+) isomer (McN-5652-X) binds to the 5-HT uptake site in vivo and the (-) isomer (McN-5652-W) does not, the possibility exists that regional-specific binding can be determined by subtracting nonspecific binding of the (-) isomer from total radioactivity counts obtained with the (+) isomer. [11C]McN-5652-X is the best PET radioligand for the 5-HT uptake site described thus far. This tracer warrants further testing in nonhuman primates. Efforts are underway to obtain an investigational new drug application for use of the tracer in humans. Promising candidates as SPECT imaging agents for the 5-HT uptake site are [123I]RTI-55 and [123I]-iodo-6-nitroquipazine. Both agents are under intense investigation in different laboratories in the United States.

[Clinical utility of thallium-201 chloride in the diagnosis of parathyroid glands in patients with hyperparathyroidism]

Clinical utility for detection of hyperfunctioning parathyroid glands in patients with primary and secondary hyperparathyroidism (PHPT, SHPT) using 201TlCl and 99mTcO4-images was estimated in 50 patients including 18 PHPT and 32 SHPT (male; n = 31, female; n = 19, 51.5 +/- 11.1 yr). Detection of 94 hyperfunctioning parathyroid glands in 34 cases were achieved correctly by 201TlCl and 99mTcO4- images in agreement with surgical findings. Detectability of hyperfunctioning parathyroid glands was 100% in more than 1.0 g, 62.0% in more than 0.5 g and 41.5% in less than 0.5 g respectively. Ectopic parathyroid glands in two cases and a metastasis to pretracheal lymph node in one case were clearly demonstrated. Our results show that parathyroid scintigraphy using 201TlCl and 99mTcO4- as well as 131I or 123I is useful and safe method for preoperative detection of hyperfunctioning parathyroid glands.

A PET radiotracer for studying serotonin uptake sites: carbon-11-McN-5652Z

A radioligand for imaging central serotonin (5-hydroxytryptamine; 5-HT) uptake sites by positron emission tomography (PET) has yet to be developed. Such a tracer would be useful for the study of normal and altered serotonergic neurotransmission as well as for the detection of serotonergic neurotoxicity. This paper describes the labeling of the highly potent serotonin (5-HT) uptake blocker, McN-5652-Z (trans-1,2,3,5,6,10 beta-hexahydro-6-[4-(methylthio)phenyl]pyrrolo-[2,1-a]-isoquinoline; racemic mixture), with 11C and the evaluation of this radiotracer in rodents with respect to its in vivo binding characteristics. In mouse brain, 11C-McN-5652-Z accumulated rapidly in regions with high densities of 5-HT uptake sites. The ratio between hypothalamus and cerebellum was 1.5:1 at 15 min and increased with time to 4.6:1 at 90 min after injection. The distribution of 11C-McN-5652 in rat brain at 60 min correlated well with regional concentrations of 5-HT uptake sites (r = 0.86). The specificity and selectivity of 11C-McN-5652 binding to the 5-HT transporter were tested by preinjecting blocking doses of known 5-HT, dopamine and norepinephrine uptake inhibitors, and a 5-HT2 receptor blocker before injection of the radiotracer. Preinjection of increasing doses of unlabeled McN-5652-Z inhibited 11C-McN-5652-Z binding in a dose-dependent fashion. These results suggest that the in vivo binding of the radiotracer was specific, selective for 5-HT uptake sites, saturable and that 11C-McN-5652-Z holds promise as a radiotracer for PET imaging of 5-HT uptake sites in the mammalian brain.

[11C](+)McN5652 as a radiotracer for imaging serotonin uptake sites with PET

The in vivo behavior of the stereoisomers of [11C]McN5652, a highly potent serotonin (5-HT) uptake blocker, was determined to evaluate their utility as radiotracers for imaging 5-HT uptake sites by positron emission tomography (PET). After intravenous injection into mice, [11C](+)McN5652 showed markedly higher uptake and longer retention in regions with high density of 5-HT uptake sites than the [11C]-labeled racemic mixture, while [11C](-)McN5652 washed out rapidly. With the [11C](+)-enantiomer, the ratio between hypothalamus and cerebellum reached 6 at 90 minutes. The binding of [11C](+)McN5652 was inhibited by 45-73% by pre-injection of 5 mg/kg of paroxetine, a selective 5-HT uptake blocker, in all regions examined except cerebellum where no significant effect of the drug was observed. [11C](-)McN5652 showed no specific binding in any of the regions. The [11C]-labeled cis isomer, [11C]McN5655, revealed surprisingly low brain penetration and showed no significantly higher uptake in regions of interest than cerebellum. These results suggest that [11C](+)McN5652 is a promising candidate as a PET radiotracer for studying 5-HT uptake sites in vivo.

Localization of hyperfunctioning parathyroid glands by means of thallium-201 and iodine-131 subtraction scintigraphy in patients with primary and secondary hyperparathyroidism

The accuracy of the preoperative localization of hyperfunctioning parathyroid glands by subtraction scintigraphy with 201Tl and 131I was evaluated by comparison with the operative findings. The subjects were 67 consecutive patients with hyperparathyroidism (HPT), including 24 with primary and 43 with secondary HPT. In primary HPT, surgery revealed 26 adenomas weighing 0.26-15.80 g (mean +/- SD; 3.01 +/- 3.04 g). Two patients had double adenomas. Scintigraphy correctly localized 25/26 adenomas (96.2%) in primary HPT for a sensitivity, specificity, and accuracy of 96.2%, 98.5%, and 97.9%, respectively. In secondary HPT, 163 hyperplastic glands weighing 0.03-5.08 g (0.85 +/- 0.93 g) were found. Scintigraphy correctly localized 79 glands (48.5%) weighing 0.03-5.08 g (1.19 +/- 1.10 g), but 84 glands (51.5%) weighing 0.04-2.70 g (0.51 +/- 0.50 g) were not detected. Thus, the sensitivity, specificity, and accuracy of scintigraphy were respectively 48.5%, 100%, and 51.2%, in secondary HPT. These results show that scintigraphy with 201Tl and 131I can be used to locate abnormal parathyroid glands with an efficacy equal to or better than that of the conventional methods with 201Tl and 99mTc or 201Tl and 123I.

Synthesis and biodistribution of a new radiotracer for in vivo labeling of serotonin uptake sites by PET, cis-N,N-[11C]dimethyl-3-(2',4'-dichlorophenyl)-indanamine (cis-[11C]DDPI)

A new PET radiotracer for in vivo labeling of serotonin (5-HT) uptake sites, cis-N,N-[11C]dimethyl-3-(2',4'-dichlorophenyl)-indanamine, cis-[11C]DDPI, was synthesized and its biological behavior was studied. The radiosynthesis of cis-[11C]DDPI was performed by N-methylation of cis-N-methyl-3-(2',4'-dichlorophenyl)-indanamine with [11C]iodomethane. The average radiochemical yield was approx. 8%, with an average specific activity of 600 mCi/mumol. Following intravenous administration, cis-[11C]DDPI accumulated in mouse brain regions rich in 5-HT uptake sites, such as olfactory tubercles, hypothalamus and frontal cortex. Following pre-injection of 1 mg/kg of paroxetine, a high affinity 5-HT uptake blocker, the binding of cis-[11C]DDPI in the olfactory tubercles, hypothalamus and frontal cortex was decreased by 23, 25 and 16%; this corresponds to 73, 82 and 59% of the specific binding in these regions. These results suggest that the accumulation of cis-[11C]DDPI in the tissues rich in 5-HT sites is a result of specific binding of cis-[11C]DDPI to 5-HT uptake sites. Due to the relatively high non-specific uptake and slow clearance of this compound from non-specific binding sites, the ratio between specific and non-specific binding increased slowly with time, reaching 1.5:1 at 60 min after injection.

[Fundamental evaluation of ELSA.F-beta HCG kit as an immunoradiometric assay specific for serum beta HCG]

We evaluated ELSA.F-beta HCG kit as an immunoradiometric assay (IRMA) specific for serum beta human chorionic gonadotropin (beta hCG). This IRMA was found to be highly sensitive to serum beta hCG; the minimum detectable concentration of beta hCG was 0.05 ng/ml. No significant effects on the standard curves were observed when first and second incubation time and temperature were varied from 30 min to 240 min and from 4 degrees C to 37 degrees C, respectively. Commercial LH, FSH, and TSH had little effect on the assay system; the cross-reactivity of commercial hCG was 2.5%, and 0.14% after unconjugated beta hCG with alpha-subunit was absorbed with ELSA-tube. Multiple dilutions of sera of pregnancy resulted in curves paralleling that obtained using standard beta hCG; the recovery of beta hCG added to the serum was 98.1 +/- 2.5% (mean +/- SD), and mean coefficient of variation of the interassay reproducibility of serum beta hCG (n = 10) was 6.7 +/- 2.8 (SD)%. Serum beta hCG concentration measured using ELSA.F-beta HCG kit was well correlated with that measured using conventional beta hCG RIA kit (r = +0.961, p less than 0.01), although values were lower than those measured with the latter (y = 0.35x + 0.26). Our results suggest that ELSA.F-beta HCG kit is a useful assay system for serum beta hCG.

Serum thymidine kinase, a possible marker for monitoring the effect of bone marrow transplant treatment in early recovery phase

We measured serum thymidine kinase (TK) activity with a radioenzyme assay system employing [I-125]-iododeoxyuridine as the tracer on serial specimens from five bone marrow transplant (BMT) patients before and after transplantation. The serum level of TK activity in the 4 patients with effective BMT treatment ranged from 3.0 to 16.9 U/L (mean, 7.80 U/L) before transplantation and from 27.3 to 236.1 U/L (mean, 82.95 U/L) after the BMT treatment. Mean serum TK activity increased 13.17-fold (range, 1.68 to 29.14-fold). In contrast, the activity in the patient with ineffective BMT treatment was not significantly different during, before, or after BMT treatment. In addition, serum TK activity in BMT patients was well correlated with the change in the number of leukocytes before and after BMT treatment [r = +0.709 (p less than 0.01), y = 0.012 x +0.87]. We conclude that the determination of serum TK activity in BMT patients is very useful in monitoring the course of bone marrow transplantation in the early recovery phase.

Myocardial uptake of antimyosin antibody compared with serum myosin light chain I levels in patients with myocardial infarction

Myocardial accumulation of In-111-antimyosin (InAM) was evaluated in comparison with circulating serum myosin light chain I (LCI) level at the time of InAM injection. Seventeen consecutive patients were studied at various stages ranging from 6 days to 34 days after myocardial infarction (MI). The infarct area was positive for InAM uptake in all patients (100%), and significant myocardial uptake was observed in 14 patients (82.4%). The intensity of InAM uptake correlated with the infarct location shown by ECG and CAG. In contrast, 12 patients (70.6%) had normal or undetectable serum myosin LCI levels, with 5 being normal (0.42-2.5 ng/ml) and 7 undetectable (0.42 ng/ml or less). Only 5 patients (29.4%) had elevated serum myosin LCI levels at the time of InAM injection, and this elevation was slight, ranging from 3.4 to 4.5 ng/ml (mean: 3.75 ng/ml). Among patients with undetectable, normal, and elevated serum myosin LCI levels, there was no significant correlation between InAM uptake and the serum myosin LCI level. Thus, even after the serum myosin LCI level has decreased to normal, InAM can still bind to cardiac myosin in patients with MI, presumably until there is complete recovery from the hibernating myocardium due to ischemic damage.

Detection of bile leakage into the thoracic cavity by hepatobiliary scintigraphy

We report early detection of bile leakage into the thoracic cavity by hepatobiliary scintigraphy in a rare case of spontaneous withdrawal of the catheter for percutaneous transhepatic cholangiographic drainage (PTCD). An 81-year-old man with inoperable carcinoma of the common bile duct was readmitted with a 38 degrees C fever and suspected bile leakage from the hepatic biliary tree following withdrawal of the catheter for PTCD. While plain X-ray immediately after readmission revealed no abnormality in the chest or abdomen, hepatobiliary scintigraphy revealed not only bile leakage into the right thoracic cavity but also the site of laceration. We conclude that hepatobiliary scintigraphy is a simple, non-invasive procedure useful in the early detection and localization of bile leakage following spontaneous withdrawal of the catheter for PTCD.

Radiosynthesis and evaluation of N-(3-[18F]fluoropropyl)paroxetine as a radiotracer for in vivo labeling of serotonin uptake sites by PET

To visualize serotonin uptake sites by positron emission tomography (PET), N-(3-[18F]fluoropropyl)-paroxetine ([18F]FPP), a derivative of the selective serotonin uptake blocker paroxetine, was synthesized from 3-[18F]fluoropropyltosylate and paroxetine via a one-pot procedure. The rate of formation of [18F]FPP was a function of the ratio of the initial amount of paroxetine to that of 1,3-propanediol bistosylate with which [18F]fluoropropyltosylate was synthesized. When the reaction mixture contained an excess amount of paroxetine over that of the propyl-bistosylate, the radiosynthesis followed by HPLC purification, which took approx. 90 min, gave [18F]FPP in a radiochemical yield of approx. 8%, and in high radiochemical and chemical purity. The specific activity was 2640 +/- 360 mCi/mumol. The brain biodistribution of [18F]FPP showed no distinguishable localization in regions with high density of serotonin uptake sites such as hypothalamus or olfactory tubercles. In vitro binding assays revealed that N-fluoropropylation of paroxetine reduced the affinity for the serotonin uptake site by three orders of magnitude.

In vivo labeling of the dopamine D2 receptor with N-11C-methyl-benperidol

A new dopamine D2 receptor radiotracer, N-11C-methyl-benperidol (11C-NMB), was prepared and its in vivo biologic behavior in mice and a baboon was studied. Carbon-11-NMB was determined to bind to specific sites characterized as dopamine D2 receptors. The binding was saturable, reversible, and stereospecific. Kinetic studies in the dopamine D2 receptor-rich striatum showed that 11C-NMB was retained five times longer than in receptor-devoid regions, resulting in a high maximum striatal-to-cerebellar ratio of 11:1 at 60 min after injection. From frontal cortex and cortex, on the other hand, the tracer washed out as rapidly as it did from cerebellum, resulting in tissue-to-cerebellar ratios close to one in these regions at any time after injection. Blocking studies confirmed the specificity and selectivity of the 11C-NMB binding to the dopamine D2 receptor. A PET study with 11C-NMB of the baboon brain revealed highly selective labeling of dopamine D2 receptor sites which was blocked by preinjection of raclopride.

[Effects of an increase or decrease in the middle ear pressure on tympanic membrane vibrations (experimental study by holographic interferometry)]

The effects of positive and negative pressure in the middle ear on tympanic membrane (TM) vibrations were studied in twenty canine temporal bones by holographic interferometry. The displacement of the TM was measured by moiré topography. 1) When pressure was applied to the tympanic cavity, the curvature of the TM became small under negative pressure and large under positive pressure, with the displacement being greater under positive pressure. 2) Without pressure load, the vibration pattern below 2 kHz was simple and there were peak displacement regions in the posterior and anterior parts of the membrane and the peaks occurred approximately halfway along the manubrium. The TM vibrations showed sectional patterns, above 3 kHz in the posterior and above 4 kHz in the anterior. The amplitude of the anterior peak was larger than that of the mallear tip, but smaller than that of the posterior. 3) At frequencies below 2 kHz, the vibration pattern was not affected by negative pressure load. At frequencies of 3 kHz or higher, the sectional patterns changed into the simpler patterns and the sectional vibrations diminished as the pressure increased. 4) Below 2 kHz, the TM amplitude decreased with increasing negative pressure. Above 3 kH, the amplitude showed an initial increase but decreased at higher negative pressure loading. With the amplitude of the mallear tip, the same tendency was observed. The resonance frequency shifted to a higher frequency range with pressure loading. 5) Under positive pressure, the vibration pattern remained unchanged below 2 kHz, and above 3 kH, sectional vibrations changed to the simple vibrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Bromination, no-carrier-added radiobromination and simultaneously-occurring chlorination by chloramine T

Factors regulating initial rates of bromination, no-carrier-added radiobromination and simultaneously-occurring chlorination by chloramine T were studied using a neuroleptic drug spiperone as the substrate. Besides the factors such as initial concentrations of chloramine T, substrate and bromide ions, upon which the rates were dependent in first, second or zero-order, the water-acetic acid composition or the hydrogen ion concentration of the solutions, where the reactions took place, was found to play a key role. By controlling these factors, optimal radiobromination conditions, where radiobromination proceeds effectively whilst simultaneously-occurring chlorination is kept from proceeding at a high rate, thus resulting in radiobrominated radiopharmaceuticals of high specific activity (10 Ci/mumol) and high radiochemical and chemical purity, could be fulfilled.

Abnormal 13C-fatty acid breath tests in patients treated with valproic acid

Breath tests using fatty acids labeled with a stable isotope (carbon 13) were carried out on epileptic patients treated with valproic acid in order to detect abnormal fatty acid metabolism. The patients were given 13C-octanoic acid or 13C-palmitic acid orally, and expired air was collected at appropriate intervals for the analysis of 13CO2 content by a mass spectrometer. Eight patients were tested in the palmitic acid breath test and nine patients in the octanoic acid breath test. Controls for these tests were patients treated with antiepileptic drugs other than valproic acid and unmedicated cerebral palsy patients. In the valproic acid-treated group, 13C recovery was reduced by 56% in seven hours on the 13C-palmitic acid breath test, while the octanoic acid breath test showed a 52% reduction in one hour. This suppression of fatty acid oxidation was significantly correlated with dose of valproic acid in both tests. No influence of other drugs was detected, and the effect of administered carnitine was not conclusive. This study demonstrates the usefulness of 13C-labeled fatty acid breath tests in clinical practice.

[13C]methacetin breath test for evaluation of liver damage

Methacetin undergoes rapid O-dealkylation by hepatic microsomal enzyme systems, and the resultant CO2 is present in the expired air. The rate of O-dealkylation of methacetin was assessed by the [13C]methacetin breath test in seven healthy volunteers and 30 patients with histologically proven chronic liver diseases. The 30-min recovery of orally administered [13C]methacetin as 13CO2 in the exhaled air was significantly reduced in patients with chronic aggressive hepatitis and in those with liver cirrhosis but not in patients with chronic persistent hepatitis or healthy controls. Patients with either advanced cirrhosis or hepatocellular carcinoma showed significantly lower values than those with well-compensated cirrhosis. The levels in two patients with late primary biliary cirrhosis were reduced. These results show that the severity of liver damage can be effectively evaluated by [13C]methacetin breath test. In addition, this test is simple, safe, and time efficient.

Automated 13CO2 analyzing system for the 13C breath test

An automated 13CO2 analyzing system for the 13C breath test was designed, built and evaluated. The system, which was designed to be controlled by a micro-computer, includes CO2 purification, 13CO2 abundance measurement, data processing and data filing. This article gives the description of the whole system with flow charts. This system has proved to work well and it has become feasible to dispose of 5 to 6 CO2 samples per hour. With such a system, the 13C breath test will be carried out much more easily and will obtain much greater popularity.