Phosphatase activity toward abnormally phosphorylated tau: decrease in Alzheimer disease brain

Microtubule-associated protein tau is abnormally hyperphosphorylated and aggregated in affected neurons of Alzheimer disease brain. This hyperphosphorylated tau can be dephosphorylated at some of the abnormal phosphorylated sites by purified protein phosphatase-1, 2A, and 2B in vitro. In the present study, we have developed an assay to measure protein phosphatase activity toward tau-1 sites (Ser199/Ser202) using the hyperphosphorylated tau isolated from Alzheimer disease brain as substrate. Using this assay, we have identified that in normal brain, protein phosphatase-2A and 2B and, to a lesser extent, 1 are involved in the dephosphorylation of tau. The Km values of dephosphorylation of the hyperphosphorylated tau by protein phosphatase-2A and 2B are similar. The tau phosphatase activity is decreased by approximately 30% in brain of Alzheimer disease patients compared with those of age-matched controls. These findings suggest that a defect of protein phosphatase could be the cause of the abnormal hyperphosphorylation of tau in Alzheimer disease.

The effects of an algal polysaccharide from Gloiopeltis tenax on transplantable tumors and immune activities in mice

Funoran (an algal polysaccharide from Gloiopeltis tenax) significantly inhibited the growth of Ehrlich ascites carcinoma and solid Ehrlich, Meth-A fibrosarcoma, and Sarcoma-180 tumors. In tumor-bearing mice, funoran significantly induced the enhancement of delayed-type hypersensitivity response to sheep red blood cells. When given intraperitoneally, funoran increased the spleen weight of mice. Morphological observations indicated that funoran augmented the transformation from lymphocytes to plasma cells in the spleen. In addition, changes in the T-cell subsets in the spleen, thymus, and peripheral blood were measured by flow cytometry. The results showed that the percentages of L3T4+ and Lyt 2+ T-cells were markedly increased in the peripheral blood. The percentages of asialo CM1+ cells in the thymus and peripheral blood were also significantly increased. Our results suggest that the antitumor effect of funoran is related to the augmentation of T-helper, T-cytotoxic, and NK cells.

Dephosphorylation of Alzheimer paired helical filaments by protein phosphatase-2A and -2B

Microtubule-associated protein tau is abnormally hyperphosphorylated in the brain of patients with Alzheimer disease and in this form is the major protein subunit of the paired helical filaments (PHF), the most prominent lesion of the disease. In this study the dephosphorylation of sparingly soluble PHF, PHF II-tau by brain protein phosphatase (PP)-2A1 and PP-2B, and the resulting biochemical, biological, and structural alterations were investigated. Both of the phosphatases dephosphorylated PHF II-tau at the sites of Ser-199/Ser-202 and partially dephosphorylated it at Ser-396/Ser-404; in addition, PHF II-tau was dephosphorylated at Ser-46 by PP-2A1 and Ser-235 by PP-2B. The relative electrophoretic mobility of PHF II-tau increased after dephosphorylation by either enzyme. Divalent cations, manganese, and magnesium increased the activities of PP-2A1 and PP-2B toward PHF II-tau. Dephosphorylation both by PP-2B and PP-2A1 decreased the resistance of PHF II-tau to proteolysis by the brain calcium-activated neutral proteases (CANP). The ability of PHF II-tau to promote the in vitro microtubule assembly was restored after dephosphorylation by PP-2A1 and PP-2B. Microtubules assembled by the dephosphorylated PHF II-tau were structurally identical to those assembled by bovine tau used as a control. The dephosphorylation both by PP-2A1 and PP-2B caused dissociation of the tangles and the PHF; some of the PHF dissociated into straight protofilaments/subfilaments. Approximately 25% of the total tau was released from PHF on dephosphorylation by PP-2A1. These observations demonstrate that PHF II-tau is accessible to dephosphorylation by PP-2A1 and PP-2B, and dephosphorylation makes PHF dissociate, accessible to proteolysis by CANP, and biologically active in promoting the assembly of tubulin into microtubules.

Kinetic images of neuronal activity of the human brain based on the spatio-temporal MNLS inverse: a theoretical study

Prior work proved that it is possible to find a unique solution to the problem of defining the configuration of electric current underlying observed extracranial magnetic fields, if sufficient priori knowledge of the source configuration is available. This minimum-norm least-squares (MNLS) inverse solution for a magnetic source image (MSI) is extended here to include temporal as well as spatial parameters of the underlying current pattern. This capitalizes on the temporal resolution of magnetoencephalography (MEG), which is on the order of milliseconds. Other forms of functional brain imaging are far less sensitive to the rate of change of states of the brain. Influences on the quality of the resulting MSI by measurement noise and errors in determining the image surface are characterized. A new technique for reducing noise in the inverse problem is developed by taking into consideration the spatial and time-dependence of the noise detected by the sensors. This new approach to regularization reduces the contribution from noisy measurements to the inverse calculation, and therefore improves the stability of the inverse.

Semiautomatic evaluation of left ventricular diastolic function with cine magnetic resonance imaging

RATIONALE AND OBJECTIVES

Cine magnetic resonance (MR) imaging is a relatively new technique that can be used to study cardiac function with high spatial and temporal resolution. However, detailed functional analysis of the entire cardiac cycle with cine MR imaging is time consuming and labor intensive. We analyzed diastolic function using a semiautomatic routine that reduces the time necessary for analysis.

METHODS

Twenty subjects (10 normal control subjects and 10 patients with isolated diastolic dysfunction) were examined. Short-axis cine MR images were obtained at 32 phases of the cardiac cycle. A semiautomatic boundary-finding routine was used to determine left ventricular (LV) volumes at each phase. Volume-versus-time and first-derivative curves were created from these data. Several parameters derived from the MR imaging curves were used to characterize diastole.

RESULTS

Two parameters--the ratio of early peak filling rate to late peak filling rate and the percentage of filling during early diastole--perfectly distinguished subjects with LV diastolic dysfunction from the normal control subjects. The semiautomatic analysis method substantially reduced the time necessary for analyzing the MR imaging data, compared with manual analysis.

CONCLUSION

Cine MR imaging, especially with time-saving techniques such as our service automatic analysis method, has promise as a research and clinical tool in evaluating LV diastolic function.

An investigation of pedigrees of 110 patients with Graves' disease and the clinical significance of determinations of antithyroid antibodies of their first-degree relatives

Eight hundred and ten pedigree members of 110 patients with Graves' disease were studied. In 700 first-degree relatives, inquiry of medical history, physical examination (including eyes, thyroid, heart rate, etc), thyroid function tests (serum T3, T4 and TSH levels), determinations of thyroglobulin antibodies (TgAb) and thyroid microsomal antibodies (TmAb) were performed. For male (female) probands, the incidence of Graves' disease in male (female) first-degree relatives were investigated and their serum TgAb and TmAb were analysed. The incidence of these two kinds of autoantibodies in the male (female) first-degree relatives of familial and nonfamilial Graves' disease were analysed. Eighteen persons with positive TgAb and TmAb from 5 pedigrees had been followed up one year after initial determinations. Our results suggest that the positive rates of TgAb and TmAb in the first-degree relatives of Graves' disease were coincident with the incidence of Graves' disease, and the positive results of TgAb and TmAb in the first-degree relatives of Graves' disease may be an indicator of pre-Graves' disease or pre-autoimmune thyroid diseases.

[Iatrogenic osteoporsis: six case reports]

Iatrogenic osteoporosis is a very common secondary osteoporosis is found in patients treated with large dosage of glucocorticosteroid of long duration. Six cases listed in this article including 2 cases of bronchial asthma, 2 cases of bronchial asthma, 2 cases of rheumatoid arthritis, 1 case of skin disease and 1 case of callagenosis (three male patients and three female patients). The age is from 27-46. The duration of treatment of primary disease with glucocorticosteroid is 1 to 3.5 years, with the average of 1.56 years. With the exception of one case treated with Dexamethasone one of 0.75g daily, the other 5 cases are treated with predinisone of 5-30mg daily. After they treated with hormone every other day and added Calcium and vitamin D and followed up 1 year, the mineral contents in the bone of all 6 patients are increased and the biochemistry indexes are improved.

[Effects of chloroform, chlorobenzene and polychlorinated biphenyls on erythrocyte lipid peroxidation and membrane fluidity in poisoned rabbits]

Effects of three chlorinated compounds, i.e., chloroform, chlorobenzene and Aroclor 1254 (PCBs), on lipid peroxidation and membrane fluidity of erythrocytes in poisoned rabbits were studied. Results revealed daily intraperitoneal injection of peanut oil containing chlorinated compounds into rabbits showed nonenzymic promotion effects on its erythrocyte lipid peroxidation in varying degrees, but different effects on erythrocyte membrane fluidity, promoting by chloroform and inhibiting by Aroclor 1254. It suggested the constitutional characteristics of toxicant molecules also had effects on membrane fluidity. In addition, it was found there existed potential relationship between maintenance of cell morphology and membrane fluidity.

[Analytical study on processing of Rheum palmatum L. by HPLC]

This paper deals with the effect of processing on Rheum palmatum. A HPLC method for the determination of rhein in the drug processed five different ways has been established. The method is simple, specific and accurate. The recovery is 98.52% and relative standard deviation.

IL-1 induces intracisternal type A virus and retrovirus type C in pancreatic beta-cells of NOD mice

Recent observations have suggested a role for interleukin 1 (IL-1), a macrophage-derived cytokine, in the autoimmune beta-cell destruction, that is associated with type 1 diabetes. In this study, we investigated the effects of human recombinant IL-1 beta on pancreatic beta-cells from NOD and NON mice (diabetes-resistant NOD-related strain), focussing upon the appearance of intracisternal type A virus (IAP) and retrovirus type C. NOD mice pancreatic islets were incubated with or without IL-1 (0.1, 1, 10, 100 U/ml) for 10 days. Thereafter, the islets were examined using an electron microscope. When the islets of NOD mice were incubated with the IL-1 (10, 100 U/ml) under condition of high glucose, IAP and endogenous retrovirus type C frequently appeared in the beta-cells. Retrovirus type C was present as a cluster. In contrast, IAP and retrovirus type C were rarely found in beta-cells from the control group. When the islets of NON mice were incubated with or without IL-1 (10 U/ml) in the presence of high glucose, IAP was rarely found in beta-cells and retrovirus type C was undetectable in beta-cells. This study indicated that IL-1 is an important effector that leads to insulitis or aggravates insulitis in NOD mice.

[Determination of hesperidin in Pericarpium Citri Reticulatae by HPLC]

A HPLC method for the determination of hesperidin in Pericarpium Citri Reticulatae has been established in this report. The method is simple, specific and accurate. The recovery of hesperidin is 98.3% and relative standard deviation 0.2%.

[An experimental study on photosensitization of cultured human cells with hypocrellin A]

The photosensitive effects of hypocrellin A on cultured HeLa cells were studied by the methods of immunofluorescence cytochemistry, flow cytometry and others. The results showed that, in the presence of 3.66 mumol/L hypocrellin A, illumination of HeLa cells with visible light, the morphology was changed and the microvilli on the cells were disappeared; the proliferation of the cells decreased with increasing irradiated dose and this effect seemed more sensitive in tumor cells than in normal cells; the increased population of cycle cells at S phase but decreased at G1 phase were observed by FCM; the photodamage effect of hypocrellin A induced the sparse distribution of cytoplasmic microtubles and almost disappearance of the fluorescence intensity of MTOC, they were observed in HeLa cells as shown by immunofluoresent microscopy. All the aforesaid results indicated that photosensitization of hypocrellin A inhibits cells growth, resulting from the damage in cell membrane and cytoskeleton and S phase delay of the cell cycle.

[Analytical study on processing of Scutellaria baicalensis Georyl by HPLC]

This paper deal with the effect of processing on Scutellaria baicalensis. A HPLC method for the determination of baicalin in the drug processed in four different ways has been established. The method is simple, specific and accurate. The recovery is 99.5% and relative standard deviation 0.99%.

MNLS inverse discriminates between neuronal activity on opposite walls of a simulated sulcus of the brain

The minimum-norm least-squares inverse for magnetic field measurements is applied to a representation of a sulcus of the human brain, where one or both walls have regions of neuronal activity. Simulations indicate that the magnetic source image (MSI) is largely confined to the appropriate wall of the sulcus, even for a depth of 4 cm where the distance between walls is only 3 mm. Two nearly oppositely oriented dipoles located 3 mm apart are found to be distinguished. Influences on the quality of the MSI by measurement noise and inaccuracy in determining the image surface are discussed in detail.

The character of endogenous retrovirus in pancreatic beta-cells of NOD mice

The character of retrovirus type C in NOD mouse pancreatic-beta-cells was investigated. First, the in vitro response of retrovirus type C to glucose stimulation was examined. When the pancreatic islets of control NON mice were observed with an electron microscopy retrovirus types C could not be detected in the beta-cells with or without glucose stimulation. Retrovirus type C particles and intracisternal type A particles (IAPs) in NOD mouse pancreatic beta-cells increased by glucose stimulation, but the increase in retrovirus type C differed from that of IAPs. The clusters of retrovirus type C were found in some beta-cells, whereas IAPs were scattered in beta-cells. Next, we investigated the expression of retrovirus type C transcript in NOD mouse pancreatic islets. From polymerase chain reaction analysis using two primers of retrovirus type C designed from a conserved U3 region, a major product was found to be endogenous polytropic retrovirus (Pmv). The subcloned PCR probe and oligonucleotide probes specific for Pmv and modified polytropic retrovirus were used for Northern blot analysis. Pancreatic islets from NOD and NON mice (control mice) contained 8.4-kb and 3.0-kb Pmv transcripts. The quantity of transcripts of Pmv in NOD mouse pancreatic beta-cells were the same as that in NON mice. The transcript level of islets was much higher than those of thymus and liver. The appearance of retrovirus type C particles in beta-cells of NOD mice may involve the mechanisms by which diabetes is generated in NOD mice.

The effect of carbenoxolone on the peripheral metabolism of cortisol in human patients

Carbenoxolone in human patients induces a state that is similar to that seen in the syndrome of apparent mineralocorticoid excess. The mechanism in both the drug-induced and the naturally occurring disorder is thought to be the inhibition of a normal mechanism for preventing access of cortisol to the mineralocorticoid receptor, namely 11 beta-hydroxy dehydrogenation. We took the opportunity to study the effect of carbenoxolone on the peripheral metabolism of cortisol in the course of evaluating the drug's therapeutic effectiveness in pseudohypoaldosteronism. Carbenoxolone, at a dose that induces mineralocorticoid effects in patients with normally responsive mineralocorticoid receptor systems, did not lead to significant changes in the urinary cortisol: cortisone tetrahydrometabolite ratio. There was, however, a marked inhibition of ring A reduction of both cortisol and cortisone to tetrahydro metabolites. Urinary cortisol level was not significantly changed, but urinary cortisone level was decreased and the cortisol:cortisone ratio markedly increased. We conclude that the urinary cortisol:cortisone tetrahydrometabolite ratio is not necessarily a valid measure of effective inhibition of 11 beta-hydroxy dehydrogenation. A better measure of the inhibitory effect of carbenoxolone on 11 beta-hydroxy dehydrogenation is the urinary free cortisol:cortisone ratio.

[A comparative study on cholagogic effect of Artemisia]

The result suggests that the cholagogic effect of A. anethoides, A. haichowenesis and A. capillaris are not different significantly (P > 0.05), but the duration of action caused by anethoides and haichowenesis is longer than that caused capillaris. The cholagogic effect of A. capillaris collected in seedling, flower budding (beginning of autumn) and preflower periods were also investigated separately, and the preflower collection was found more cholagogic.

[Vitreo-retinal surgery for complicated retinal detachment]

93 eyes (93 patients) of complicated retinal detachment were treated with vitreo-retinal surgery. Among the series, 75 eyes were rhegmatogenous with PVR C3-D3 in 66 eyes (88.0%), while the remaining 18 eyes were traction induced. None of the cases had giant tears or complicating diabetes. On discharge from the hospital, the operation was effective in 62 cases (66.7%), in whom the retina was totally reattached or only a small amount of subretinal fluid remained. In a group of 40 eyes where the inert gas SF6 was used, the operation was effective in 30 cases (75.0%). 41 cases were followed up postoperatively for over 3 months, averaging 13.7 months, to find the operative results stable in 33 eyes (80.5%), with the visual acuity improved in 22 cases (66.7%), unchanged in 9 cases (27.3%), and decreased in 2 cases (6.0%). The operative procedures, the peeling of pre-retinal membrane, the effect of PVR severity on the operative results, and the promotion of operative efficacy by application of wide encircling buckle and inert gas tamponade were discussed.

Antitumor activity of a new low immunosuppressive derivative of podophyllotoxin (GP-11) and its mechanisms

The spin-labeled derivative of podophyllotoxin, N'-podophyllic acid-N-[3-(2,2,5,5-tetramethyl pyrrolinenyloxy)] semicarbazide (GP-11), was synthesized and tested for its antitumor activity against mouse transplantable tumors, Sarcoma-180, Hepatoma-A, P388 leukemia and Ehrlich ascites carcinoma. At an equitoxic dose, the antitumor activity of GP-11 was similar to that of etoposide (VP-16). However, the immunosuppressive effects of GP-11 were weaker than that of VP-16. In vitro, GP-11 and VP-16 inhibited the proliferation of human lymphoid leukemia Molt 4B cells and suppressed DNA and protein syntheses, but the effect of GP-11 and VP-16 on cell cycle progression was different. The mitotic index was increased by GP-11 and reduced by VP-16. On the basis of flow cytometric bromodeoxyuridine (BrdU)/DNA analysis, GP-11 and VP-16 resulted in the accumulation of cells in the S and G2/M phases. G2/M arrest by GP-11 on cell cycle progression was stronger than that of VP-16, while S arrest was weaker than that of VP-16. After the removal of drugs, the arrest by GP-11 and VP-16 still existed and was irreversible. These results may provide insights into the structure-activity relationships and the design of novel derivatives of podophyllotoxin useful in cancer chemotherapy.

Minimum-norm least-squares estimation: magnetic source images for a spherical model head

This paper extends the minimum-norm least-squares inverse approach to a local spherical model for the conductivity geometry of the human head. In simulations of cortical activity of the human brain, the magnetic field pattern across the scalp is interpreted with prior knowledge of anatomy, and the properties of intraneuronal current flow to yield a unique magnetic source image across a portion of cerebral cortex. Influences on the quality of magnetic source images from the noise in measurements, the position error in determining the image surface, and the number of sensors are evaluated in detail.

The unique steroidogenesis of the aldosteronoma in the differential diagnosis of primary aldosteronism

18-Hydroxycortisol and 18-oxocortisol have been isolated from the urine of patients with aldosterone producing adrenocortical adenomas, but not from those with idiopathic hyperaldosteronism associated with bilateral adrenal hyperplasia. These C-18 oxygenated cortisols are biosynthesized by the substitution of cortisol for the normal substrate, corticosterone, in the terminal oxidase system required for the biosynthesis of 18-hydroxycorticosterone and aldosterone. To make use of this biochemical difference between the two groups in the preoperative diagnosis of primary aldosteronism, we have developed and utilized a specific primary standard analytical method, stable isotope dilution mass fragmentography, for quantifying 18-hydroxycortisol and the tetrahydro metabolite of 18-oxocortisol in 24-h urine samples. The normal range by this technique of 4.6 +/- 1.8 micrograms/day tetrahydro 18-oxocortisol and 43 +/- 23 micrograms/day 18-hydroxycortisol in urine was lower and narrower than previous estimates using other methods. Excretion of the 18-oxocortisol metabolite ranged from 2-12 micrograms/day in bilateral hyperplasia and 17-1203 micrograms/day in typical adenomas. 18-Hydroxycortisol excretion similarly separated bilateral hyperplasia (23-59 micrograms/day) from typical adenomas (60-2750 micrograms/day). The cortisol C-18 oxidation pathway describes a unique steroidogenic mechanism in the aldosteronoma not present in idiopathic aldosteronism due to bilateral adrenal hyperplasia and as such provides a basis for the biochemical classification of primary aldosteronism and the differentiation of these two groups. This unique biochemistry was also observed in unilateral hyperplasia but not in the renin-dependent aldosteronoma.

Biochemical and morphological alterations of macrophages and spleen cells produced by antitumor polysaccharide from Acanthopanax obovatus roots

Acanthopanax obovatus polysaccharide (AOPS) administrated intraperitoneally (i.p.) resulted in the augmentation of phagocytosis and the chemiluminescence in peritoneal macrophages of mice. Binding of the third component of complement (C3) cleavage products to the receptors on peritoneal macrophages was enhanced by AOPS. The C3 conversion in human serum was increased by AOPS in vitro treatment. When given i.p., AOPS led to the enhancement of spleen weight, spleen cell number, and plaque-forming cells. It was also found that after in vivo administration AOPS not only enhanced the synthesis of DNA and protein but also promoted the mitogenic responses of spleen cells. The morphological observation of spleens indicated that AOPS augmented the transformation from lymphocytes to plasma cells. AOPS inhibited the growth of mouse solid Sarcoma-180 and prolonged the survival time significantly. These results suggest that AOPS is an effective biological response modifier and its antitumor activity is related to its immunopotentiating effects.

A cohort study in southern China of tin miners exposed to radon and radon decay products

Several studies of underground miners have demonstrated that exposure to radioactive radon gas (more precisely, 222Rn and its short-lived decay products) at levels historically found in mines increases the risk of lung cancer. Because of small numbers of lung cancers, previous studies have had limited power to evaluate temporal and other characteristics of patterns of risk. Herein we report on a historical cohort study of male employees of the Yunnan Tin Corporation in southern China. The cohort consists of 17,143 workers with 175,143 person-years of observation and 981 lung cancer events. Eighty percent of the workers were employed underground and exposed to radon. The excess relative risk increased linearly with exposure, rising 0.6% per working level month (95% confidence interval = 0.4-0.8). In the mines, workers were also exposed to arsenic-containing dusts. Adjustment for arsenic exposure, a known lung carcinogen, reduced the effect of radon exposure to 0.2% per working level month (95% confidence interval = 0.1-0.2). The excess relative risk/working level month declined significantly with attained age and with radon exposure rate as measured by the cumulative working level month divided by duration of exposure. It also declined significantly with years from last exposure and with time since exposure, but these declines were consistent only after adjustment for arsenic exposure. In this cohort, 41% of the underground workers were first exposed when < 15 y old; however, lung cancer risk did not vary consistently with age at first radon exposure. A joint analysis of radon exposure and smoking status (smoker vs. nonsmoker) rejected both an additive and a multiplicative association; the relationship was consistent with an intermediate association.

Imaging regional changes in the spontaneous activity of the brain: an extension of the minimum-norm least-squares estimate

This paper describes methods for inferring mathematically unique local distributions of primary cortical current that underly changes in the average pattern of power of the ongoing ("spontaneous") extracranial magnetic field of the brain. In previous work we demonstrated that mathematically unique solutions to the inverse problem are possible for current sources of the brain's field, without assuming a small set of current dipoles as a source model. In principle, it is possible to locate and delineate patterns of current of any configuration. In practice this approach applies to synchronized neuronal activity, e.g., activity which is known to underly average evoked or event-related brain responses. This paper extends that approach to local changes in incoherent activity, e.g., activity yielding fields or potentials that tend to be self-cancelling when averaged over time. This includes the spontaneous brain activity normally treated as background noise when it accompanies event-related responses. We demonstrate that local changes in this ongoing incoherent activity may also be uniquely delineated in space and time. The solution is a covariance matrix characterizing activity across an image surface. Its diagonal elements represent the spatial pattern of mean current power. Evidence is reviewed indicating that the distribution of the brain's magnetic field, due to both its synchronized and incoherent neural activity, is affected by early sensory-perceptual processes and by higher cognitive processes. Hence, in principle, the ability to delineate both kinds of sources in space and time makes it possible to form more comprehensive dynamic functional images of the human brain.

Magnetic source imaging based on the minimum-norm least-squares inverse

The flow of ionic currents within the neurons of cerebral cortex produces a magnetic field that can be detected outside the human scalp. The dominant contribution is attributed to pyramidal cells, which are preferentially oriented perpendicular to the cortical surface. In general, it is not possible to deduce a unique representation of the spatial configuration of these cortical sources from a measurement of their field pattern alone. However, accurate a priori knowledge of the geometry of the underlying cerebral cortex makes it possible to infer the spatial configuration of these transcortical current sources, moment by moment, without imposing a simplified model such as a small set of current dipoles. To achieve such a realistic magnetic source image, we have introduced what we call the "Minimum-Norm Least-Squares Inverse" (MNLS inverse) for the magnetic problem. The MNLS inverse provides the least residual error in accounting for the measured field pattern, with a source current distribution having minimum power. An extension of this procedure provides an inverse solution for average field power, as opposed to field per se. This makes it possible to define spatial configurations of spontaneous cortical activity not phase-locked to a sensory stimulus. Rhythmic activity such as the occipital alpha rhythm is one example. Thus, it is possible to determine spatial patterns of enhanced or suppressed cortical rhythms that accompany cognitive processes and some pathological conditions. This paper provides the necessary background for understanding these recent developments, as well as examples of how they might be used.

[Neurological manifestation of Takayasu's arteritis]

38 cases of Takayasu's arteritis were reported. The mean age of onset was 23.3 years with a female: male ratio of 1:1.7. The median delay between first symptom and time of diagnosis was 12.2 years. Headache was the most common symptom of neurologic manifestations (55%). Major neurologic events occurred in 52.7% patients in this group, including TIA, cerebral infarction, hypertensive encephalopathy, lacunar infarct, seizure, paraplegia, watershed infarct, cerebral hemorrhage, Moyamoya phenomenon, and confusion in the order of frequency. A variety of mechanisms that must be taken into account in explaining this neurologic events were proposed. The secondary hypertension and cardiac complications play an important role in causing neurologic symptoms. The formation of anastomotic networks has "Jekyll and Hyde" effect on brain both in preventing or limiting the ischemic injury and in producing some special symptoms and signs, that further widen the clinical spectrum of brain involvement.

Fast, interactive algorithm for segmentation of a series of related images: application to volumetric analysis of MR images of the heart

Magnetic resonance (MR) cine images of the beating heart have excellent spatial and temporal resolution. Extracting the boundaries of the heart from MR images for volumetric measurements is of considerable interest; however, since the number of images involved is large, tracing the boundaries by hand is tedious and prohibitively time consuming. The authors have developed an interactive method of boundary detection that uses the correlation between the cardiac boundaries on temporally or spatially adjacent images to increase the speed of the process and reproducibility of the measurement. A simulated cine MR study of a phantom (total of 155 images) and cardiac cine studies of two patients (192 images each) were analyzed by two independent observers. Analysis of the phantom data was completed in 5.6 minutes (2.16 seconds per image) by observer 1 and 6.3 minutes (2.4 seconds per image) by observer 2. The percent measurement errors for 31 phantom volumes (30-120 mL) were 0.96% and 0.83% for observers 1 and 2, respectively. The observers analyzed the patient studies in 14-23 minutes (4.4-7.2 seconds per image), with interobserver variabilities of 5.8% and 3.7% for the two patients, respectively. The authors conclude that their flexible, semiautomatic, interactive algorithm allows rapid and reproducible detection of structural boundaries.

Antitumor activity of polysaccharide from a Chinese medicinal herb, Acanthopanax giraldii Harms

The results of experiments with Acanthopanax giraldii polysaccharide (AGP) demonstrated that it inhibited the growth of solid Sarcoma 180 and prolonged the survival time significantly. In tumor-bearing mice, AGP enhanced the phagocytosis and chemiluminescence of macrophages. By the immunofluorescent method, binding of the third component of complement (C3) cleavage product to macrophages and proportion of C3 positive cells were increased. In crossed immunoelectrophoresis, human serum C3 was converted by AGP and appeared as the 3rd peak. The height of the 3rd peak was directly proportional to doses of AGP. The residual CH50 units of human serum decreased dose-dependently. These results suggest that the antitumor activity of AGP is related to the enhancement of immune responses.

Magnetic source images determined by a lead-field analysis: the unique minimum-norm least-squares estimation

The minimum norm least-squares approach based on lead field theory provides a unique inverse solution for a magnetic source image that is the best estimate in the least-squares sense. This has been applied to determine the source current distribution when the primary current is confined to a surface or set of surfaces. In model simulations of cortical activity of the human brain, the magnetic field pattern across the scalp is interpreted with prior knowledge of anatomy to yield a unique magnetic source image across a portion of cerebral cortex, without resort to an explicit source model.

The biochemical phenotypes of two inborn errors in the biosynthesis of aldosterone

Two inborn errors in the methyl oxidation of corticosterone to form aldosterone correspond to the two oxygenation-hydroxylation reactions required for this transformation. Both defects are characterized by overproduction of corticosterone of glomerulosa zone origin and deficient synthesis of aldosterone. In the type 1 corticosterone methyl oxidase defect (CMO I) impairment in the first step is reflected in decreased production of 18-hydroxycorticosterone while in CMO II an impaired second step is characterized by overproduction of 18-hydroxycorticosterone leading to an increased 18-hydroxycorticosterone:aldosterone metabolite ratio as a diagnostic index. This metabolite ratio may be increased somewhat in CMO I but not as much as in CMO II. The absolute value of 18-hydroxycorticosterone is a more reliable discriminator as is the corticosterone:18-hydroxycorticosterone metabolite ratio which is increased in CMO I and decreased in CMO II. On the basis of these findings, a North American kindred is reclassified as CMO I making this defect the more prevalent form in the Western Hemisphere. The two biochemical phenotypes will very likely describe different mutations in the gene encoding cytochrome P-450 CMO.

Risk of lung cancer among cigarette and pipe smokers in southern China

Studies in Shanghai and in north-east China indicate that cigarette smoking is a major contributor to the high rates of lung cancer in those areas, but doubts persist regarding the influence of cigarette use on lung cancer rates in other areas of China. In addition, the risk of lung cancer associated with other methods of tobacco consumption--in particular, the use of bamboo water-pipes and long-stem pipes--is uncertain. A population-based case-control study of 427 male lung cancer patients residing in a mining area of Southern China and 1,011 controls was carried out to address this and other issues. Of these patients, 63% smoked cigarettes and (water and long-stem) pipes; 17% and 14% smoked only cigarettes or pipes, respectively; and 6% did not smoke. Compared to non-smokers, smokers of cigarettes only, smokers of pipes only and mixed smokers were at increased risk; OR = 2.6 (95% CI 1.1-6.2), 1.8 (95% CI 0.8-4.2) and 4.1 (95% CI 2.3-9.2), respectively. Risk increased with duration of tobacco use; however, the rate of increase with years of cigarette use was significantly greater than for years of pipe use (p = 0.03). In addition, risks increased 8-fold in the highest quartile of number of cigarettes per day compared to non-cigarette smokers vs. 2.3-fold for the highest quartile of number of liang (50 g) smoked per month compared to non-pipe-smokers; the trends in the ORs differed significantly (p less than 0.001). Results suggest that, in this area of China, tobacco use is an important cause of lung cancer, and that smoking cigarettes may be more deleterious than smoking pipes (primarily water pipes).

Glucocorticoid-remediable aldosteronism in a large kindred: clinical spectrum and diagnosis using a characteristic biochemical phenotype

OBJECTIVE

To define the clinical spectrum of glucocorticoid-remediable aldosteronism (GRA) in a large kindred.

DESIGN

Screening all at-risk relatives of a proband for GRA using a specific biochemical phenotype and collecting of medical histories of kindred members from five generations.

SETTING

Outpatient General Clinical Research Centers and patients' homes.

MEASUREMENTS

Screening was done while patients were on a self-selected diet and included blood pressure determinations; serum potassium and plasma renin activity and aldosterone measurements; and 24-hour urinary tetrahydroaldosterone, 18-oxotetrahydrocortisol, and 18-hydroxycortisol measurements.

RESULTS

Diagnosis of GRA was established on the basis of a previously described specific biochemical abnormality, overproduction of the cortisol C-18 oxidation products (18-oxotetrahydrocortisol and 18-hydroxycortisol) in urine and their ratio relative to tetrahydroaldosterone. Glucocorticoid-remediable aldosteronism was diagnosed in 11 additional patients spanning three generations; this group included the youngest patient (3 months old) ever diagnosed with GRA. Complete penetrance of the biochemical abnormality is likely, with 11 of 18 at-risk patients displaying the phenotype. All patients with GRA had elevated blood pressure. Affected adult patients had been diagnosed as hypertensive before reaching 21 years of age (n = 7 mean, 16.1 +/- 3.4 years). All affected patients were normokalemic (4.3 +/- 0.3 mmol/L).

CONCLUSION

Hypertension is a characteristic feature of GRA. Elevated blood pressure in this kindred developed at an early age and often was severe. Because a normal potassium level does not exclude the diagnosis of GRA, the disorder may be underdiagnosed. The value of a specific cortisol C-18 oxidation phenotype in the diagnosis of GRA has been confirmed.

Cortisol inactivation overload: a mechanism of mineralocorticoid hypertension in the ectopic adrenocorticotropin syndrome

The more severe mineralocorticoid manifestations in the ectopic ACTH syndrome compared to pituitary Cushing's disease have been attributed to hypersecretion of 11-deoxycorticosterone. Another difference between the two forms of ACTH-excess, however, is a more severe degree of hypercortisolism in the ectopic syndrome. Cortisol can become a potent mineralocorticoid if its peripheral metabolism is interfered with as occurs in the syndrome of apparent mineralocorticoid excess. This mechanism also occurs in an experimental model of the apparent mineralocorticoid excess syndrome induced by licorice derivatives. We have tested the hypothesis that cortisol is a major mineralocorticoid in the ectopic ACTH syndrome because of two factors, marked hypersecretion and incomplete peripheral metabolism of cortisol as a result of an overload of metabolizing enzymes. Two measures of the peripheral metabolism of cortisol were found to be markedly decreased in two patients with the ectopic ACTH syndrome. The cortisol turnover quotients were 17.2 and 19.6 (normal = 215 +/- 98) and the ring A reduction constants were 11.8 and 13.8 (normal = 101 +/- 23). These values were comparable to that found in the syndrome of apparent mineralocorticoid excess and consistent with the hypothesis that cortisol is a significant functioning mineralocorticoid in the ectopic ACTH syndrome.

Changes in cortical activity when subjects scan memory for tones

The magnetoencephalogram (MEG) was used to detect regional changes in spontaneous cortical activity accompanying short-term memory search. This method was chosen because magnetic fields are detectable only within a few centimeters of the projections of their sources onto the scalp. The specific hypothesis that auditory cortex is involved in scanning memory for tones was tested by sensing the field of the magnetic counterpart to N100 (N100m) which is known to originate in auditory cortex. N100m was measured at many different positions and the spontaneous cortical rhythms in the alpha bandwidth (8-12 Hz) were measured at the same places. These rhythms were found to be suppressed while subjects scanned memory for musical tones in a Sternberg paradigm. For 3 subjects, both the MEG suppression time (ST) and reaction time (RT) increased linearly with memory set size. The correlation between ST measured over the left hemisphere and set size was significant for two subjects but not significant for the third, and the slopes of the regression lines relating ST to set size were too shallow to be related to the time required to scan memory. However, the correlation between ST of the right hemisphere and set size was highly significant for all subjects, and the slopes of the regression lines were comparable to those relating RT to set size. The electroencephalogram (EEG) recorded with midline electrodes failed to reveal a significant relationship between suppression time and set size for 2 of the subjects, thus ruling out global alpha blockage and generalized arousal as the basis for the task-related suppression duration. The electric N100, measured at Cz, decreased significantly in amplitude with set size for 2 subjects, but it increased significantly in amplitude for the third subject. In contrast, RT increased with set size for all subjects. N100m measured over the right hemisphere was similar to the behavior of N100, while N100m measured over the left hemisphere showed little change in amplitude with set size, thus establishing an asymmetry in N100 between the hemispheres. Since N100 amplitude is normally larger when attention is paid to auditory stimuli, differential attention alone cannot account for the relation between ST and set size. Furthermore, the processing negativity, which may be superimposed on N100 in selective attention tasks, was not discernible for any set size. It was also found that ST prior to the button press was not correlated with RT. Hence, the covariation of set size with ST is not attributable to preparation for a motor response.(ABSTRACT TRUNCATED AT 400 WORDS)

Dietary determinants of lung-cancer risk: results from a case-control study in Yunnan Province, China

The relation between diet and lung cancer was studied among male residents of a mining community in Yunnan Province. After obtaining food frequency data from subjects or proxies, we compared diets of 428 cases, aged 35-74 years, and 1,011 age-matched controls. Cases tended to consume slightly more rice, but less protein-rich foods (i.e., bean curd, meat, eggs) and vegetables than did controls. The relative risks of lung cancer across increasing quartiles of meat (i.e., pork) consumption, for example, were 1.00, 0.67, 0.72 and 0.46 (p for trend less than 0.01). The relative risks of lung cancer across increasing quartiles of consumption of dark-green, leafy vegetables were 1.00, 0.62, 0.52 and 0.41 (p for trend less than 0.01). Although specific dietary constituent(s) responsible for the protective effect of vegetable consumption could not be identified, carotenoids other than beta-carotene, or compounds in cruciferous or Allium vegetables, are possibilities.

Maturation and fertilization of porcine oocytes in vitro

Four experiments were conducted to study 1) factors affecting porcine oocyte maturation in culture medium and 2) a new method for oocyte maturation outside the porcine body. In Experiment 1, five groups of oocytes were cultured in m-TCM199 or m-KRB medium for 24 to 28, 32 to 36 or 40 to 42 hours and then were fertilized in vitro. The cleavage rate (two to four-cell stage) of oocytes cultured for 32 to 36 hours was significantly higher than those of the other oocytes. The results indicate that a suitable culture period for the in vitro maturation of porcine oocytes is 32 to 36 hours. In Experiment 2, four groups of oocytes were cultured in m-KRB or m-KRB supplemented with PFF, PMSG or FSH for in vitro maturation, and the cleavage rates of oocytes were 7.94, 22.56, 30.23 and 23.26%, respectively, after in vitro fertilization. The results show that porcine follicular fluid (PFF) and gonadotrophins added to the culture medium promote porcine oocyte maturation in vitro. In Experiment 3, oocytes were cultured in m-KRB or m-TCM199, supplemented with both gonadotrophin and pocine folliclar fluid for maturation in vitro. After fertilization in vitro, the cleavage rates of oocytes were 26.32 and 27.93% for the two media. The results indicate that the difference between m-KRB and m-TCM199 was insignificant when the media were used to culture porcine oocytes. But there was a significant difference when PFF and gonadotrophins were added to the basic media. In Experiment 4, porcine oocytes were transferred into the reproductive tracts of other animals for maturation. After 34 to 36 hours, the oocytes were collected and fertilized in vitro. The cleavage rates of oocytes were 10.42, 28.45, 3.33 and 36.36%, respectively, for the oocytes matured in mouse uterine horns, rat uterine horns, rat oviducts or rabbit oviducts. The results show that porcine oocytes can be matured in the reproductive tracts of other animals.

Defective ring A reduction of cortisol as the major metabolic error in the syndrome of apparent mineralocorticoid excess

Impaired peripheral metabolism of cortisol in the syndrome of apparent mineralocorticoid excess is currently understood to be causally related to the severe but otherwise unexplained manifestations of mineralocorticoid excess. A normally ambivalent mineralocorticoid receptor responding equally well to glucocorticoids and mineralocorticoids requires prereceptor inactivation of glucocorticoids to elicit a specific mineralocorticoid effect. The failed inactivation step in the form of the syndrome of apparent mineralocorticoid excess first described (type 1) involves the 11 beta-hydroxydehydrogenation of cortisol to cortisone. In another form of the syndrome (type 2) this conversion occurs normally in the face of otherwise similar clinical and biochemical features. Markedly decreased cortisol metabolic clearance in the type 2 form suggested impairment of a major component of that clearance, ring A reduction. A noninvasive method was developed for measuring the conversion of cortisol to tetrahydrocortisol and allotetrahydrocortisol, and this step was found to be profoundly decreased in both type 1 and type 2 forms. Thus, the major abnormality in the peripheral metabolism of cortisol common to both forms involved ring A reduction, not 11 beta-hydroxydehydrogenation. Since ring A reduction was better correlated with the manifestation of mineralocorticoid excess in both forms of the syndrome, this step might also be a normal major prereceptor mechanism conferring mineralocorticoid specificity.

Sequence and genomic structure of the human adult skeletal muscle sodium channel alpha subunit gene on 17q

The amino acid sequence of the sodium channel alpha subunit from adult human skeletal muscle has been deduced by cross-species PCR-mediated cloning and sequencing of the cDNA. The protein consists of 1836 amino acid residues. The amino acid sequence shows 93% identity to the alpha subunit from rat adult skeletal muscle and 70% identity to the alpha subunit from other mammalian tissues. A 500 kb YAC clone containing the complete coding sequence and two overlapping lambda clones covering 68% of the cDNA were used to estimate the gene size at 35 kb. The YAC clone proved crucial for gene structure studies as the high conservation between ion channel genes made hybridization studies with total genomic DNA difficult. Our results provide valuable information for the study of periodic paralysis and paramyotonia congenita, two inherited neurological disorders which are caused by point mutations within this gene.

A Met-to-Val mutation in the skeletal muscle Na+ channel alpha-subunit in hyperkalaemic periodic paralysis

HYPERKALAEMIC periodic paralysis (HYPP) is an autosomal dominant disease that results in episodic electrical inexcitability and paralysis of skeletal muscle. Electrophysiological data indicate that tetrodotoxin-sensitive sodium channels from muscle cells of HYPP-affected individuals show abnormal inactivation. Genetic analysis of nine HYPP families has shown tight linkage between the adult skeletal muscle sodium channel alpha-subunit gene on chromosome 17q and the disease (lod score, z = 24; recombination frequency 0 = 0), strongly suggesting that mutations of the alpha-subunit gene cause HYPP. We sequenced the alpha-subunit coding region isolated from muscle biopsies from affected (familial HYPP) and control individuals by cross-species polymerase chain reaction-mediated complementary DNA cloning. We have identified an A----G substitution in the patient's messenger RNA that causes a Met----Val change in a highly conserved region of the alpha-subunit, predicted to be in a transmembrane domain. This same change was found in a sporadic case of HYPP as a new mutation. We have therefore discovered a voltage-gated channel mutation responsible for a human genetic disease.

Magnetic resonance imaging of the rabbit knee: detection of cartilage proteoglycan degradation

Intra-articular (i.a.) injection of papain causes a reversible loss of proteoglycan in intact rabbit knees. Twelve rabbits were scanned with magnetic resonance imaging (MRI) at 0, 24, 48 and 72 hours after 5 units of papain i.a. in a 1.5 Tesla Signa with a three inch surface coil using spin echo sequence. Total cartilage thickness in proton density images was 1.08 +/- 0.09 mm prior to papain injection. The magnetic resonance images showed a reduction in articular cartilage thickness in papain-treated rabbit femurs at 24 hours to 0.69 +/- 0.18 mm and partial restoration by 72 hours to 0.77 +/- 0.21 mm.

On cortical folds and neuromagnetic fields

A folded cortical source of neuromagnetic fields, similar in configuration to the visual cortex, was simulated. Cortical activity was modelled by different distributions of independent current dipoles. The map of the summed fields of the dipoles of this cruciform model changed, depending upon the statistical distribution of the electrical activity of the dipoles and its geometry. Arrays of dipoles of random orientations and strengths produced field patterns that could be interpreted as due to moving neural currents, although the geometry of the neural tissue remained unchanged and the average activity remained approximately constant. The field topography at any instant was apparently unrelated to the depth or orientation of the underlying structure, thus raising questions about how to interpret topographic MEG and EEG displays. Furthermore, asynchronous activity (defined as independent directions and magnitudes of activity of the dipoles) did not result in less field power than when the dipoles were synchronized, i.e., when the direction of current flow was correlated across all of the dipoles within the cruciform structure. Therefore, in this model 'alpha blockage' cannot be mimicked by desynchronization. More generally, for the cruciform or any other symmetrically folded and active cortical sheet, 'blockage' cannot be attributed to desynchronization. The same is true for the EEG except that smooth unfolded sheets of radially oriented dipoles would result in enhancement of voltage due to synchronization. Such radial dipoles do not contribute to the MEG. Blockage was simulated by reducing the amount of activity within different portions of the synchronized cruciform model. This resulted in a dramatic increase in the net field because attenuation broke the symmetry of the synchronized cruciform structure. With asynchronous dipoles populating the structure, the attenuation of the same portion of the structure had no easily discerned effect on the net field. However, maps of average field power were consistently related to the position of the region of attenuated activity. The locations of regions of attenuated activity were determined by taking the difference between the mean square field pattern obtained when all portions of the cruciform structure were active and the pattern obtained when a portion of the structure was relatively inactive. When activity of the same portions were incremented rather than attenuated, the resulting plot of average power was essentially the same as that of the attenuated portion derived by taking these differences between power distributions. The major conclusions are that the concepts of synchronization and desynchronization have no explanatory power unless the physical conditions under which they occur are specified precisely.(ABSTRACT TRUNCATED AT 400 WORDS)

[Effect of Salvia miltiorrhiza co. on angiotensin II and atrial natriuretic polypeptide in rabbits]

Both angiotensin II (AII) and atrial natriuretic polypeptide (ANP) are related to the function of blood vessels, but differ in their actions. The authors observed the effect of Salvia miltiorrhiza Co. (SMC) on the activities of AII and ANP in rabbits by radioimmunoassay. It was found that the concentration of AII and ANP in plasma were significantly lower (P less than 0.05), and slightly lower in brain and atrial (P greater than 0.05) in SMC group than in control group. It indicated that the effect of SMC on blood vessels is related to changes of AII and ANP, and that the difference of peptide changes in brain and plasma might be due to the blood-brain barrier.

The use of magnetic resonance imaging in the study of edema

A method of studying edema using magnetic resonance imaging (MRI) is presented. Three patients with lower extremity edema due to congestive heart failure were imaged with a 0.6 tesla system before and after diuresis. Edge detection algorithms were utilized to precisely outline regions of interest for quantification. Water and nonwater elements were separated within the region of interest to quantify water content. The results show that: (1) Edema can be quantified by use of MRI. (2) Subcutaneous edema is distributed along defined planes (ie, nonuniformly). (3) Increased water content is present not only in the subcutaneous tissue but also in deeper lying muscle.

Sputum occult blood screening for lung cancer. Stage II screening of 14,431 subjects

Sputum occult blood screening (SOBS) for lung cancer was performed in outpatients with suspected lung cancer. A total of 1011 patients were seen. Among them, 604 patients were found to be negative for SOBS, and 407 were found to be positive. The false-negative rate was 3.97% (24 of 604), and the opposite positive rate was 19.65% (80 of 407). A total of 14,431 normal subjects over 40 years of age were screened by SOBS. In the series, 1942 specimens were found to be positive. Among the 1942 patients, 31 were found to have definite cancer cells.

Synthesis of a deuterium-labeled cortisol for the study of its rate of 11 beta-hydroxy dehydrogenation in man

11 beta-Hydroxy dehydrogenation of cortisol to cortisone is specifically impaired in the syndrome of apparent mineralocorticoid excess. This defect bears on the pathogenesis of the disorder by unmasking the potential mineralocorticoid agonism of unmetabolized cortisol at or near mineralocorticoid target tissues. A specific index of this defect is provided by measurement of the formation of tritiated water following the administration of [3H]11 alpha-cortisol. We have explored the use of a non-radioactive tracer to follow this unidirectional dehydrogenation reaction but because of the relatively lower sensitivity of measurement of 2H2O compared to 3H2O in body fluids, use of the corresponding [2H]11 alpha-cortisol was not feasible. We have devised instead a method incorporating additional deuterium atoms into cortisol to measure unidirectional 11 beta-hydroxy dehydrogenation not by the formation of labeled water but by the determination of the dehydrogenated cortisol product from its residual deuterium content. Cortisol-d4 metabolized to cortisone-d3 is conveniently measured by the techniques of organic mass spectrometry. The synthesis of cortisol-9 alpha, 11 alpha, 12 alpha 12 beta-d4 and the validation of its isotopic distribution by mass spectrometry and nuclear magnetic resonance is described.

[Resistant action of gangliosides on the 6-OHDA injured sympathetic nerves]

A single dose of 6-OHDA (15 mg/kg i.p.) would cause an almost complete disappearance of catecholamine fluorescence in histological preparation of submandibular glands (SMG) 24 hours after injection. Recovery of NA and DA levels went on slowly along with the course of regeneration of the lesioned sympathetic nerve terminals. The NA and the DA contents reached 50% and 28% respectively two weeks after lesion and fully recovered by the end of the fourth week. Gangliosides mixture (GM) (50 mg/kg i.p.) given 0, 4, 8, and 12 hours after 6-OHDA injection could prevent the injury action of NA and DA for at least 24 hours. If this treatment was followed by daily injection for one week, the NA contents remained normal by the end of two weeks. GM treatments beginning either 4 days before or 4 hours after 6-OHDA injection could lessen the extent of decrease of NA and DA by 6-OHDA. The results suggest that: a) GM is effective in protecting the membrane of sympathetic terminals from the injurious effect of 6-OHDA or 6-OHDA metabolites and promoting the regeneration of the lesioned terminals. b) The earlier the GM treatments are given, the better will be the effects.

Magnetic resonance imaging reflects cartilage proteoglycan degradation in the rabbit knee

Cartilage degeneration in osteoarthritis is initiated by a loss of proteoglycan. Intra-articular injection of papain causes a reversible loss of proteoglycan in rabbit knees. Rabbits were scanned with magnetic resonance imaging (MRI), using a 1.5T Signa superconducting magnet with 3 inch surface coil. Spin echo sequences were performed in the coronal and sagittal planes at 0, 24, 48, and 72 h after intra-articular injection of papain to obtain T1, proton density, and T2-weighted images. Cartilage proteoglycan content was measured biochemically and histochemically. Reduced articular cartilage thickness in the MR images of papain-treated knees corresponded to changes in cartilage proteoglycan content.

Inhibition of lung metastasis by a calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7), in mice bearing Lewis lung carcinoma

The antimetastatic effect of calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) was examined in an experimental model of lung metastasis induced by Lewis lung carcinomas (3LL) in C57BL/6crSlc mice. 3LL cells were implanted into the footpad of the mice. Ten days later, the implanted primary tumors were surgically removed. Injection of W-7 i.v. after removal of the implanted primary tumor caused the greatest inhibition of development of lung metastases. The number of peritoneal macrophages, total cells and macrophages in the lung increased in mice treated with W-7. Binding of the third component of complement (C3) cleavage products (C3b) to the C3 receptor on peritoneal macrophages after i.v. injection of W-7 were enhanced, as shown by the fluorescent antibody technique. Lung metastases were inhibited by i.v. injection of peritoneal macrophages activated with W-7. A possible mechanism of inhibition of lung metastases by treatment with W-7 could be interpreted as due to C3 activation and macrophage activation. These findings raise the possibility that W-7 may have clinical value in the prevention of cancer metastasis.

Measurement of 4 urinary C-18 oxygenated corticosteroids by stable isotope dilution mass fragmentography

The cortisol C-18 oxidation pathway leading to the production of 18-hydroxy- and 18-oxocortisol is expressed in adenomatous primary aldosteronism and glucocorticoid remediable aldosteronism. In order to better define the significance of the pathway and its usefulness in differential diagnosis, we have developed a stable isotope dilution mass fragmentographic method for the determination of the tetrahydro metabolites of aldosterone, 18-hydroxycorticosterone and 18-oxocortisol and of unmetabolized 18-hydroxycortisol in urine. Stereochemically correct tetrahydro steroids containing 3 deuterium atoms were synthesized from the available 3-keto-4-pregnenes in 2 steps and 1,2-deuterium-labeled 18-hydroxycortisol was prepared by selective deuteration of the 1,2-double bond of a dienone precursor. Simultaneous measurement of the 4 steroids permitted a comparison of the abnormal products of the C-18 oxidation of cortisol with the normal C-18 oxidation products of corticosterone, 18-hydroxycorticosterone and aldosterone. Application of the method to the definition of the normal range is described.