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Na+,K+-ATPase is a heterodimer of alpha and beta subunits and a member of the P-type ATPase family of ion pumps. Here we present an 11-A structure of the heterodimer determined from electron micrographs of unstained frozen-hydrated tubular crystals. For this reconstruction, the enzyme was isolated from supraorbital glands of salt-adapted ducks and was crystallized within the native membranes. Crystallization conditions fixed Na+,K+-ATPase in the vanadate-inhibited E2 conformation, and the crystals had p1 symmetry. A large number of helical symmetries were observed, so a three-dimensional structure was calculated by averaging both Fourier-Bessel coefficients and real-space structures of data from the different symmetries. The resulting structure clearly reveals cytoplasmic, transmembrane, and extracellular regions of the molecule with densities separately attributable to alpha and beta subunits. The overall shape bears a remarkable resemblance to the E2 structure of rabbit sarcoplasmic reticulum Ca2+-ATPase. After aligning these two structures, atomic coordinates for Ca2+-ATPase were fit to Na+,K+-ATPase, and several flexible surface loops, which fit the map poorly, were associated with sequences that differ in the two pumps. Nevertheless, cytoplasmic domains were very similarly arranged, suggesting that the E2-to-E1 conformational change postulated for Ca2+-ATPase probably applies to Na+,K+-ATPase as well as other P-type ATPases.

Thapsigargin (TG) is a potent inhibitor of Ca(2+)-ATPase from sarcoplasmic and endoplasmic reticula. Previous enzymatic studies have concluded that Ca(2+)-ATPase is locked in a dead-end complex upon binding TG with an affinity of <1 nM and that this complex closely resembles the E(2) enzymatic state. We have studied the structural effects of TG binding by cryoelectron microscopy of tubular crystals, which have previously been shown to comprise Ca(2+)-ATPase molecules in the E(2) conformation. In particular, we have compared 3D reconstructions of Ca(2+)-ATPase in the absence and presence of either TG or its dansylated derivative. The overall molecular shape of Ca(2+)-ATPase in the reconstructions is very similar, demonstrating that the TG/Ca(2+)-ATPase complex does indeed physically resemble the E(2) conformation, in contrast to massive domain movements that appear to be induced by Ca(2+) binding. Difference maps reveal a consistent difference on the lumenal side of the membrane, which we conclude corresponds to the thapsigargin-binding site. Modeling the atomic structure for Ca(2+)-ATPase into our density maps reveals that this binding site is composed of the loops between transmembrane segments M3/M4 and M7/M8. Indirect effects are proposed to explain the effects of the S3 stalk segment on thapsigargin affinity as well as thapsigargin-induced changes in ATP affinity. Indeed, a second difference density was observed at the decavanadate-binding site within the three cytoplasmic domains, which we believe reflects an altered affinity as a result of the long-range conformational coupling that drives the reaction cycle of this family of ATP-dependent ion pumps., (Copyright 2001 Academic Press.)

The cutaneous side-effects of long-term hydroxyurea therapy are not widely known and only rarely reported. We report on a patient who developed widespread skin changes, including the recently recognized hydroxyurea dermopathy, during long-term treatment with hydroxyurea for polycythaemia rubra vera. The time course of the clinical changes suggests that they result from direct toxicity of hydroxyurea on the basal layer of the epidermis and mucosal surfaces. We aim to increase clinical awareness of this problem.

We report a case of localized granuloma annulare, successfully treated with isotretinoin, which occurred as a consequence of waxing-induced pseudofolliculitis. To our knowledge this is the first reported clearance of localized granuloma annulare with isotretinoin and the first reported case of granuloma annulare as a sequel to pseudofolliculitis.

Electron crystallography offers an increasingly viable alternative to X-ray crystallography for structure determination, especially for membrane proteins. The methodology has been developed and successfully applied to 2D crystals; however, well-ordered thin, 3D crystals are often produced during crystallization trials and generally discarded due to complexities in structure analysis. To cope with these complexities, we have developed a general method for determining unit cell geometry and for merging electron diffraction data from tilt series. We have applied this method to thin, monoclinic crystals of Ca2+-ATPase from sarcoplasmic reticulum, thus characterizing the unit cell and generating a 3D set of electron diffraction amplitudes to 8 A resolution with tilt angles up to 30 degrees. The indexing of data from the tilt series has been verified by an analysis of Laue zones near the (h, k, 0) projection and the unit cell geometry is consistent with low-angle X-ray scattering from these crystals. Based on this unit cell geometry, we have systematically tilted crystals to record images of the (h, k, 0) projection. After averaging the corresponding phases to 8 A resolution, an (h, k, 0) projection map has been calculated by combining image phases with electron diffraction amplitudes. This map contains discrete densities that most likely correspond to Ca2+-ATPase dimers, unlike previous maps of untilted crystals in which molecules from successive layers are not aligned. Comparison with a projection structure from tubular crystals reveals differences that are likely due to the conformational change accompanying calcium binding to Ca2+-ATPase., (Copyright 1998 Academic Press)

Objectives: We sought to study the utility of liver function test abnormalities concomitant with biliary symptoms in predicting a favorable response to endoscopic sphincterotomy in patients with Geenen class II sphincter of Oddi dysfunction., Methods: We reviewed the clinical course and liver function test results of 24 Geenen-Hogan class II postcholecystectomy patients with biliary colic secondary to sphincter of Oddi dysfunction who did not undergo sphincter of Oddi manometry before treatment with endoscopic sphincterotomy., Results: Twenty of the 24 patients had an average of 1.4 episodes of abnormal liver function tests associated with biliary colic; eight patients had dilated common bile duct on cholangiogram. Eighteen of the 20 patients with abnormal liver function tests (90%) were pain-free after sphincterotomy; in contrast, only one of four patients (25%) without liver function test changes responded to sphincterotomy. Fisher exact analysis showed that abnormal liver function tests was a significant predictor for favorable response to sphincterotomy with a two-tail p value of 0.018. Of the eight patients with bile duct dilatation, six (75%) responded favorably to sphincterotomy, whereas 13 of 16 patients (81%) without dilatation also responded to sphincterotomy. Analysis of common bile duct dilatation as a predictive factor showed no significance (p=1.00)., Conclusions: We conclude that the occurrence of abnormal liver function tests during biliary colic may be used to select patients for endoscopic sphincterotomy. Sphincter of Oddi manometry may not be needed in these cases.

Significant advances have recently been made in understanding the regulation of Ca(2+)-ATPase by phospholamban and in modeling their structures. However, these insights would be furthered by determining the 3-D structure of both proteins within the membrane, thus revealing the structural basis for their interaction. To this end, we have developed methods for reconstituting purified Ca(2+)-ATPase with recombinant phospholamban. After reconstitution at high lipid-to-protein ratios, we have verified their functional association by measuring calcium transport and ATPase activity. Furthermore, we have grown co-crystals after reconstitution at low lipid-to-protein ratios. The structure of Ca(2+)-ATPase has recently been solved by cryoelectron microscopy at 8-A resolution, thus revealing transmembrane alpha-helices. Using a variety of constraints, we have associated these helices with the predicted transmembrane sequences to produce a detailed model for the packing of transmembrane helices. Structure determination of the co-crystals is currently underway, which we hope will eventually reveal the interaction of phospholamban with Ca(2+)-ATPase at a similar level of detail.

Purpose: Although concomitant radiation therapy (RT) and bolus 5-Fluorouracil (5-FU) have been shown to improve survival in locally confined pancreatic cancer, most patients will eventually succumb to their disease. Since 1994, we have attempted to improve efficacy by administering 5-FU as a protracted venous infusion (PVI). This study compares treatment intensity and acute toxicity of consecutive protocols of concurrent RT and 5-FU by bolus injection or PVI., Methods and Materials: Since 1986, 74 patients with resected or locally advanced pancreatic cancer were treated with continuous course RT and concurrent 5-FU by bolus injection (n = 44) or PVI throughout the course of RT (n = 30). Dose intensity was assessed for both 5-FU and radiotherapy. Toxicity endpoints which could be reliably and objectively quantified (e.g., neutropenia, weight loss, treatment interruption) were evaluated., Results: Cumulative 5-FU dose (mean = 7.2 vs. 2.5 gm/m2, p < 0.001) and weekly 5-FU dose (mean = 1.3 vs. 0.5 gm/m2/wk, p < 0.001) were significantly higher for patients receiving PVI 5-FU. Following pancreaticoduodenectomy, 95% of PVI patients maintained a RT dose intensity of > or = 900 cGy/wk, compared with 63% of those receiving bolus 5-FU (p = 0.02). No difference was seen for patients with locally advanced disease (72% vs. 76%, p = n.s.). Grade II-III neutropenia was less common for patients treated with PVI (13% vs. 34%, p = 0.05). Grade II-III thrombocytopenia was uncommon (< or = 3%) in both treatment groups. Mean percent weight loss (3.8% vs. 4.1%, p = n.s.) and weight loss > or = 5% of pre-treatment weight (21% vs. 31%, p = n.s.) were similar for PVI and bolus treatment groups, respectively. Treatment interruptions for hematologic, gastrointestinal or other acute toxicities were less common for patients receiving PVI 5-FU (10% vs. 25%, p = 0.11)., Conclusion: Concurrent RT and 5-FU by PVI was well tolerated and permitted greater chemotherapy and radiotherapy dose intensity with reduced hematologic toxicity and fewer treatment interruptions compared with RT and bolus 5-FU. Longer follow-up will be needed to assess late effects and the impact on overall survival.

Cowden's disease is a rare autosomal dominant condition characterized by multiple hamartomas of ectodermal, endodermal, and mesodermal origin affecting many organ systems. Gastrointestinal manifestation includes the formation of multiple polyps of various benign histopathological types throughout the alimentary tract. Recent literature suggests that the frequency of gastrointestinal involvement is approximately 70-85%. The diagnosis of Cowden's disease, however, relies mainly on subtle dermatologic findings, which may not be obvious to the gastroenterologist. We describe a patient with Cowden's disease and review the English literature on the topic of gastrointestinal polyposis and Cowden's disease. These studies suggest that gastrointestinal polyposis is commonly found in this disease, and that diffuse esophageal glycogenic acanthosis is a characteristic feature of Cowden's disease. We propose that the finding of extensive glycogenic acanthosis in the presence of other benign gastrointestinal polyposis should be considered pathognomonic for the diagnosis of Cowden's disease.

In an attempt to better define the parameters governing reconstitution and two-dimensional crystallization of membrane proteins, we have studied Ca2(+)-ATPase from rabbit sarcoplasmic reticulum. This ion pump forms vanadate-induced crystals in its native membrane and has previously been reconstituted at high lipid-to-protein ratios for functional studies. We have characterized the reconstitution of purified Ca2(+)-ATPase at low lipid-to-protein ratios and discovered procedures that produce long, tubular crystals suitable for helical reconstruction. C12E8 (n-dodecyl-octaethylene-glycol monoether) was used to fully solubilize various mixtures of lipid and purified Ca2(+)-ATPase, and BioBeads were then used to remove the C12E8. Slow removal resulted in two populations of vesicles, and the proteoliposome population was separated from the liposome population on a sucrose density gradient. These proteoliposomes had a lipid-to-protein ratio of 1:2, and virtually 100% of molecules faced the outside of vesicles, as determined by fluorescein isothiocyanate labeling. Cycles of freeze-thaw caused considerable aggregation of these proteoliposomes, and, if phosphatidyl ethanolamine and phosphatidic acid were included, or if the bilayers were doped with small amounts of C12E8, vanadate-induced tubular crystals grew from the aggregates. Thus our procedure comprised two steps-reconstitution followed by crystallization-allowing us to consider mechanisms of bilayer formation separately from those of crystallization and tube formation.

In this era of cost containment, new technologies will play the same role that they did before, improvement in the quality of care. Application of these new technologies in medical practice, however, will be scrutinized much more closely. The previous requirement of proving that a new technology is efficacious and safe will no longer be adequate. Physicians will be required to provide data that reflect the costs and overall effectiveness of the new technology. This article briefly discusses some key concepts of cost-effectiveness analysis.

Electron microscopy of multilamellar crystals of CA(2+)-ATPase currently offers the best opportunity for obtaining a high-resolution structure of this ATP-driven ion pump. Under certain conditions small, wormlike crystals are formed and provide views parallel to the lamellar plane, from which parameters of lamellar stacking can be directly measured. Assuming that molecular packing is the same, data from these views could supplement those obtained by tilting large, thin platelike crystals. However, we were surprised to discover that the lamellar spacing was variable and depended on the amount of glycerol present during crystallization (20% versus 5%). Projection maps (h,0,l) from these womklike crystals suggest different molecular contacts that give rise to the different lamellar spacings. Based on an orthogonal projection map (h,k,0) from collapsed, wormlike crystals and on x-ray powder patterns, we conclude that molecular packing within the lamellar plane is the same as that in thin, platelike crystals and is unaffected by glycerol. Finally, the orientation of molecules in the lamellar plane was characterized from freeze-dried, shadowed crystals. Comparing the profile of molecules in these multilamellar crystals with that previously observed in helical tubes induced by vanadate gives structural evidence of the conformational change that accompanies binding of calcium of Ca(2+)-ATPase.

Ursolic acid (UA) and oleanolic acid (OA) were examined for anti-angiogenic activities by using the chick embryo chorioallantoic membrane (CAM) assay. The presence of UA or OA inhibited angiogenesis in a dose-dependent manner; the doses required for half-maximal inhibition (ID50) were 5 micrograms and 40 micrograms per CAM, respectively. UA was a more potent angiogenic inhibitor than OA. We also tested for inhibitory effect on the proliferation of bovine aortic endothelial cell. They effectively inhibited the proliferation of bovine aortic endothelial cell in a concentration-dependent manner. The IC50 values of anti-proliferative effects were determined to be 5 microM for UA and 20 microM for OA. Based on these results, we speculated that the inhibitory effects on bovine aortic endothelial cell proliferation of UA and OA might be important for anti-angiogenesis.

An attempt was made to isolate the active component of Eriobotrya japonica, which inhibits aflatoxin B1-induced mutagenicity in the Salmonella assay system. The number of revertants per plate was significantly decreased when a MeOH extract of Eriobotrya japonica was added to the assay system using Salmonella typhimurium TA100 or TA98. Furthermore, we examined the effect of each fraction purified from the MeOH extract, and an EtOAc fraction was found to be the most effective. Ursolic acid isolated from the EtOAc fraction markedly and significantly decreased the numbers of Salmonella typhimurium TA100 revertants per plate, thus showing antimutagenic activity.

The antimutagenic effects of 27 kinds of plant flavonoids on the mutagenicity of aflatoxin B1(AFB1) and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) in Salmonella typhimurium TA100 were investigated. In the mixed applications of AFB1 (1 microgram/plate) with the flavonoids (300 micrograms/plate) in the presence of a mammalian metabolic activation system (S9 mix), chrysin, apigenin, luteolin and its glucoside, kaempferol, fisetin, morin, naringenin, hesperetin, persicogenin, (+)-catechin and (-)-epicatechin showed the antimutagenic effect against AFB1 with more than 70% inhibition rate. A little or no antimutagenicities except flavone against MNNG (0.5 microgram/plate) were observed. For the antimutagenicity of the flavonoids on AFB1, the flavonoid structure that contains the free 5-, 7-hydroxyl group seemed to be essential. However, saturation of the 2,3-double bond or elimination of the 4-keto group did not affect the activity.

Cytochrome b5 is a microsomal membrane protein which provides reducing potential to delta 5-, delta 6-, and delta 9-fatty acid desaturases through its interaction with cytochrome b5 reductase. Low angle x-ray diffraction has been used to determine the structure of an asymmetrically reconstituted cytochrome b5:DMPC model membrane system. Differential scanning calorimetry and fluorescence anisotropy studies were performed to examine the bilayer physical dynamics of this reconstituted system. These latter studies allow us to constrain structural models to those which are consistent with physical dynamics data. Additionally, because the nonpolar peptide secondary structure remains unclear, we tested the sensitivity of our model to different nonpolar peptide domain configurations. In this modeling approach, the nonpolar peptide moiety was arranged in the membrane to meet such chemically determined criteria as protease susceptibility of carboxyl- and amino-termini, tyrosine availability for pH titration and tryptophan 109 location, et cetera. In these studies, we have obtained a reconstituted cytochrome b5:DMPC bilayer structure at approximately 6.3 A resolution and conclude that the nonpolar peptide does not penetrate beyond the bilayer midplane. Structural correlations with calorimetry, fluorescence anisotropy and acyl chain packing data suggest that asymmetric cytochrome b5 incorporation into the bilayer increases acyl chain order. Additionally, we suggest that the heme peptide:bilayer interaction facilitates a discreet heme peptide orientation which would be dependent upon phospholipid headgroup composition.

The "membrane bilayer" pathway (Rhodes, D. G., J. G. Sarmiento, and L. G. Herbette. 1985. Mol. Pharmacol. 27:612-623.) for 1,4-dihydropyridine calcium channel drug (DHP) binding to receptor sites in cardiac sarcolemmal membranes has been extended to include the interaction of amphiphiles within the lipid bilayer. These studies focused on the ability of the Class III antiarrhythmic agents bretylium and clofilium to nonspecifically inhibit DHP-receptor binding in canine cardiac sarcolemma. Clofilium was found to inhibit nimodipine binding with an inhibition constant of approximately 5 microM, whereas bretylium had no effect on nimodipine binding. Small angle x-ray diffraction was then used to examine the differential ability of these two Class III agents to inhibit DHP-receptor binding. The time-averaged locations of bretylium, clofilium, and nimodipine in bovine cardiac phosphatidylcholine (BCPC) bilayers (supplemented with 13 mol% cholesterol) were determined to a resolution of 9 A. The location of bretylium as dominated by its phenyl ring in BCPC bilayers was found to be at the hydrocarbon core/water interface, similar to that of the dihydropyridine ring of nimodipine. The location of clofilium as dominated by its phenyl ring was found to be below the hydrocarbon/core water interface within the hydrocarbon chain region of the bilayer, similar to that of the phenyl ring of nimodipine. The location of the dihydropyridine ring portion of nimodipine has previously been shown by neutron diffraction to be located at the hydrocarbon core/water interface of native sarcoplasmic reticulum, consistent with the small angle x-ray data from model membranes in this paper. Therefore, we speculate that the nonspecific inhibition arises from the interaction of clofilium's phenyl ring with the site on the calcium channel receptor where the phenyl ring portion of nimodipine must interact. The DHP-receptor binding pathway would then involve both nonspecific (membrane) and specific (protein) binding components, both of which are necessary for receptor binding.

Blood lipid levels in rats with high fat-fed hyperlipemia were determined after intraperitoneal administration of a methanolic extract of Prunus davidiana Fr. stems. Administration of the methanolic extract for 6 days produced a significant decrease of blood triglyceride and total cholesterol, and the atherogenic index was also improved. In addition to the hypolipemic effect, the methanolic extract was also shown to be effective in reducing an elevated level of glucose in rats with hyperlipemia resulting from high-fat feeding. On the other hand, blood triglyceride and total cholesterol in rats fed with stock diet were not affected by administration of the methanolic extract even if there was a tendency to decrease. No significant change was also found in the level of glucose. Thus, it is suggested that this methanolic extract probably may increase the metabolic utilization only when fed with excess fat.

A 3570 gram male newborn was born to a 29-year-old mother at the gestational age of 40 weeks with gross abnormalities of flexion contracture of third and fifth fingers and fourth toes bilaterally. After birth, cyanotic spell while feeding was found, and a series of examinations were done. The abnormalities were focused on brain echogram, computed tomogram and magnetic resonance imaging examination, which showed a large posterior fossa cyst, cerebellar hypoplasia complicated with multiple severe supratentorial anomalies, including marked ventricular dilatation, cerebral agyria, agenesis of corpus callosum, absence of thalamus and basal ganglion, and optic nerve atrophy. Clinically, the patient had neonatal seizure and high fever. The diagnosis of Dandy-Walker complex type A was made according to the new classification presented by Barkovick et al. in 1989.

Extracorporeal shock-wave lithotripsy (ESWL) has become standard therapy for the treatment of kidney stones since its introduction in 1980; a similar technique is now being used for many patients with gallstones. This article reviews the technique of biliary ESWL, examines the results of clinical studies to date, and makes recommendations as to who may ultimately benefit from this procedure.

In nine patients, with preoperative ICP monitoring, anaesthesia was induced with thiopentone 5 mg kg-1 given over 1 min, followed by pancuronium 0.1 mg kg-1. After manual hyperventilation with nitrous oxide and oxygen for 3 min they were given thiopentone 2.5 mg kg-1 over 30 s (phase 1); 30 s later laryngoscopy was performed and topical analgesia administered to the larynx. Endotracheal intubation was performed 1 min after spraying the cords (phase 2). The measurements continued for a further 5 min during which the patients were mechanically ventilated (phase 3). ICP and intra-arterial pressure were recorded. Although there was a significant decrease (P less than 0.05) in MAP at the end of the second dose of thiopentone, there were no other significant changes in ICP, MAP or PaCO2 throughout the study. In two patients there were transient decreases in cerebral perfusion pressure to less than 60 mm Hg. Although MAP increased in five of the patients during laryngoscopy and intubation, there was no increase in ICP, showing that the MAP was still within the autoregulatory limits.

Intravenous administration of 0.6 mg/kg of atracurium to nine patients did not produce any significant change in intracranial, mean arterial or cerebral perfusion pressures. In another three patients, anaesthesia was induced with thiopentone 5 mg/kg after muscle relaxation with atracurium 1 mg/kg. Intracranial pressure was below pre-induction levels in two patients whose tracheas were intubated 90 seconds after atracurium. The vocal cords were not fully relaxed at 90 seconds in the third patient. Intubation at 150 seconds in this patient was associated with a rise in intracranial pressure above pre-induction values.

The relationship between nutrition, somatomedin, and growth was studied in young male rats which were fasted for 72 h, and then refed. Cartilage growth activity was measured by the incorporation of SO4 by costal cartilage incubated in vitro. Serum somatomedin activity was measured by the ability of sera to stimulate the incorporation of SO4 in vitro by cartilage from hypophysectomized rats or normal young pigs. Cartilage growth activity was unchanged after 24 h of fasting, but decreased significantly to hypopituitary levels after 72 h. The decrease in cartilage growth activity could not be attributed to a decrease in the ability of cartilage to respond to somatomedin, since fasted rat cartilage incubated in vitro had significantly greater stimulation from the addition of normal rat serum (normal somatomedin) than from the addition of hypophysectomized rat serum (low somatomedin). A decrease in serum somatomedin preceded the decrease in growth activity; somatomedin was significantly decreased after 24 h of fasting, and fell to hypopituitary levels after 72 h of fasting. The decrease in somatomedin could not be attributed to growth hormone deficiency, since treatment with bGH did not prevent the fall in somatomedin. The direct addition of fasted rat serum to normal rat serum did not inhibit the somatomedin activity of the normal serum. The refeeding of 72h-fasted rats was associated with an increase in serum somatomedin which was significant after 6 h, and comparable to control levels after 24 h of refeeding. The increase in somatomedin was followed by an increase in cartilage growth activity, which was significant after 12 h, and comparable to control levels after 48 h of refeeding. We conclude that adequate food intake appears to be required for the maintenance of normal levels of somatomedin; the processing of nutrients may modulate the generation of somatomedin.

The non-depolarizing muscle relaxant AH8165 has been compared at two doses (0.5 and 1.0 mg/kg) with pancuronium (0.1 mg/kg) during induction of anaesthesia for patients having major cardiac surgery. After barbiturate-opiate premedication and thiopentone induction, administration of pancuronium was followed by no significant alteration in heart rate or arterial pressure. Both doses of AH8165 werr followed by significant tachycardia, and the higher dose by arterial hypotension. The lower dose of AH8165 was unsatisfactory for tracheal intubation, but the AH8165 1 mg/kg gave intubating conditions similar to those with pancuronium 0.1 mg/kg.

Since diabetes mellitus is a condition in which poor growth occurs despite elevation of plasma GH, we have attempted to determine if poor growth in diabetes, as in malnutrition, could be associated with a decrease in somatomedin activity. Young male rats were rendered diabetic with intravenous streptozotocin (STZ). The growth activity of their cartilage was estimated by 35SO4 incorporation in vitro, and somatomedin (SM) activity in their serum was determined by the stimulation of SO4 incorporation by cartilage from hypophysectomized rats or normal young pigs. Cartilage growth activity was significantly decreased 24 hours after STZ and fell to hypopituitary levels after 48 hours. The decreased growth activity could not be attributed to decreased cartilage responsiveness to SM, since incubation of diabetic cartilage with normal rat serum (normal SM) resulted in significant stimulation of cartilage SO4 incorporation. SM in diabetic serum decreased to hypopituitary levels 24 hours after STZ, and decreased further after 48 hours. The decrease in SM and cartilage growth activity was not prevented by the administration of high doses of bovine GH. The fall in bioassayable SM appeared to be due in part to the presence of an SM inhibitor in the diabetic serum, since addition of diabetic serum to normal serum decreased to measurable SM in the normal serum. Administration of insulin to diabetic rats 48 hours after STZ led to significant increases in SM and cartilage growth activity, and insulin therapy 24 hours after STZ prevented the decreases in SM and cartilage growth activity which occurred without insulin. Thus, acute STZ-induced diabetes in rats was associated with a significant decrease in both serum SM and cartilage growth activity; these changes were not ameliorated by administration of GH, and insulin therapy could both prevent and reverse the fall in SM and cartilage growth activity. From these observations, we conclude that (1) that fall in somatomedin activity and cartilage growth activity associated with STZ-induced diabetes appears to be due to insulin deficiency and (2) growth failure in diabetes, as in malnutrition, may be due to decreased somatomedin activity.

Spurred on by the discovery of "lithogenic bile" as a precursor, there has been much attention focused on the pathophysiology and treatment of gallstones. The article reviews the progress to date regarding the epidemiology, pathophysiology, diagnosis, therapy, and recurrence/prevention of gallstones.

Gas chromatographic analysis revealed that polyunsaturated fatty acids such as arachidonic acid and total tissue free fatty acids isolated from an aminopropyl bonded-phase column yield a two- to three-fold higher recovery of arachidonic acid as compared to those isolated from thin-layer chromatographic plates. This method was further improved by packing the aminopropyl bonded phase in glass columns, since the glass column significantly eliminated the other contaminants (from polypropylene columns) coeluting with fatty acids in both a neutral lipid thin-layer chromatographic system and on a 5% DEGS-PS column of gas chromatographic analysis. In aminopropyl bonded-phase columns, the standard triglycerides and phospholipids were completely separated from free fatty acids as judged by gas chromatographic analysis. These results warrant the use of an aminopropyl bonded-phase column for the isolation of free fatty acids to obtain better recovery of polyunsaturated fatty acids.

Intubating conditions after AH 8165, 1times25 mg/kg, have been compared with those after suxamethonium 1 mg/kg in 240 patients. Patients were matched for physical fitness and intubating conditions were studied in different groups at 30, 45, 60 and 75 seconds after the relaxant. At all times suxamethonium produced a higher incidence of good relaxation of the vocal cords and the incidence of excellent overall intubating conditions was significantly higher with suxamethonium. It proved impossible to intubate eleven patients with AH 8165 at the chosen time but all patients receiving suxamethonium could be intubated.

A series of carbon-14 measurements of 18th- and 19-century wood revealed an excellent correlation between the variations in carbon-14 content and average sunspot activity. It seems probable, therefore, that the predominant cause of the short-term fluctuations in carbon-14 activity is the variability of solar activity.