Prececal amino acid digestibility and phytate degradation in broiler chickens when using different oilseed meals, phytase and protease supplements in the feed

The purpose of this study was to investigate the effects of phytase and protease supplementation on prececal (pc) amino acid (AA) digestibility, phytate (InsP6) degradation, and MEn concentration in diets using 3 oilseed meals as main protein sources in broiler chicken feed. The broiler chicken diets, which lacked mineral phosphorus, contained either soybean meal (SBM), SBM and rapeseed meal (SBM/RSM), or SBM and sunflower meal (SBM/SFM) as main protein sources. Diets were not supplemented with enzymes or supplemented with 1,500 or 3,000 FTU phytase/kg, or with 1,600 mg protease/kg. For diets containing SBM as the main protein source, the effects of phytase supplementation with and without monocalcium phosphate were also investigated. Data were obtained during 2 subsequent runs from days 14 to 22 and from days 23 to 31. Each diet was tested using 8 replicates with 4 replicates per run. For pc AA digestibility, no significant interactions were observed between main protein sources, enzyme supplementation, or addition of monocalcium phosphate except for Cys. Supplementation of 1,500 FTU phytase/kg increased pc digestibility of all AA. No differences in pc AA digestibility were observed between 1,500 and 3,000 FTU phytase/kg supplementation treatments. Prececal disappearance of InsP6 and pc P digestibility were greater in the high phytase supplementation treatment. Protease supplementation increased pc digestibility of all AA except for Cys when SBM/RSM was the main protein source. Supplementation of protease and 3,000 FTU phytase/kg increased MEn concentrations. The effect of phytase on pc AA digestibility was fully expressed at a lower supplementation level than needed for a maximized pc InsP6 disappearance and MEn concentration.

Prediction of CP and starch concentrations in ruminal in situ studies and ruminal degradation of cereal grains using NIRS

Ruminal in situ incubations are widely used to assess the nutritional value of feedstuffs for ruminants. In in situ methods, feed samples are ruminally incubated in indigestible bags over a predefined timespan and the disappearance of nutrients from the bags is recorded. To describe the degradation of specific nutrients, information on the concentration of feed samples and undegraded feed after in situ incubation ('bag residues') is needed. For cereal and pea grains, CP and starch (ST) analyses are of interest. The numerous analyses of residues following ruminal incubation contribute greatly to the substantial investments in labour and money, and faster methods would be beneficial. Therefore, calibrations were developed to estimate CP and ST concentrations in grains and bag residues following in situ incubations by using their near-infrared spectra recorded from 680 to 2500 nm. The samples comprised rye, triticale, barley, wheat, and maize grains (20 genotypes each), and 15 durum wheat and 13 pea grains. In addition, residues after ruminal incubation were included (at least from four samples per species for various incubation times). To establish CP and ST calibrations, 620 and 610 samples (grains and bag residues after incubation, respectively) were chemically analysed for their CP and ST concentration. Calibrations using wavelengths from 1250 to 2450 nm and the first derivative of the spectra produced the best results (R 2 Validation=0.99 for CP and ST; standard error of prediction=0.47 and 2.10% DM for CP and ST, respectively). Hence, CP and ST concentration in cereal grains and peas and their bag residues could be predicted with high precision by NIRS for use in in situ studies. No differences were found between the effective ruminal degradation calculated from NIRS estimations and those calculated from chemical analyses (P>0.70). Calibrations were also calculated to predict ruminal degradation kinetics of cereal grains from the spectra of ground grains. Estimation of the effective ruminal degradation of CP and ST from the near-infrared spectra of cereal grains showed promising results (R 2>0.90), but the database needs to be extended to obtain more stable calibrations for routine use.

In situ and in vitro evaluation of crude protein degradation and utilisable crude protein content of barley, rye and triticale grains for ruminants

Rations for dairy cows are comprised of high proportions of cereal grains. Thus, despite their low crude protein (CP) content, grains can contribute considerably to the CP intake of dairy cows. This study was conducted to describe and compare ruminal CP degradation of a broad range of barley, rye and triticale genotypes in situ and in vitro and different methods to estimate the utilisable CP at the duodenum (uCP). Twenty samples each of rye, barley and triticale were incubated in situ and in vitro. Exponential regression analyses were used to estimate in situ degradation parameters. Further, the effective degradability (ED), ruminal undegraded CP (UDP) and uCP for ruminal passage rates of 5% and 8% per hr were estimated. The uCP was estimated in vitro and based on two different approaches using in situ UDP data and estimates of microbial synthesised protein (based on fermented organic matter [fOM] or equations of the Gesellschaft für Ernährungsphysiologie). The degradation rate declined from rye (43% per hr) to triticale (27% per hr) to barley (20% per hr), and it exhibited remarkable variation between the genotypes of a single species. The maximal degradable CP fraction also differed between the species, but was overall very high (94%-99%). The lowest washout fraction (26%) and the highest variation in ED (77%-86% and 69%-80% for a passage rate of 5% and 8% per hr, respectively) were found in barley. The in situ uCP content (estimated using fOM) was lower for barley than for rye and triticale at ruminal passage rates of 5% and 8% per hr (barley: 157 g/kg DM at both passage rates; rye and triticale: 168 (at 5% per hr) and 169 (at 8% per hr) g/kg DM). In vitro estimations of uCP did not differ between the grain species and uCP estimated according to GfE was higher for triticale than for barley and rye, which did not differ. The low variation within a single grain species and the weak correlations between ruminal CP degradation and nutrient concentrations suggested that differentiation of ED and uCP between the genotypes of a single grain species is not necessary.

Low in vitro third-body wear on total hip prostheses induced by calcium sulphate used for local antibiotic therapy

In case of implant associated infection, implant preservation is associated with high failure rates. Therefore, a removal or exchange of the implant is most often mandatory for treatment success. Alternatively, under certain conditions, local antibiotic delivery can be applied - preserving the implant, using for example calcium sulphate as a resorbable carrier. In this work, third-body wear on total hip prostheses caused by calcium sulphate particles was tested in a hip simulator. Inlays made of ultra-high-molecular-weight polyethylene (UHMWPE) and cross-linked polyethylene (XLPE) against 28 mm CoCrMo heads and 36 mm alumina pairings were tested in triplicate, both with and without calcium sulphate particles in the test liquid. Neither the alumina articulations nor the CoCrMo heads were affected by the calcium sulphate particles since calcium sulphate is a relatively soft material. The polyethylene inlays showed 39-89 % higher wear during exposure compared to references, but wear returned to normal when no more particles were added. Thus, calcium sulphate might be used as antibiotic carrier even in the presence of total hip prostheses without fearing excessive third-body wear.

[Cardiac computed tomography and ablation of atrial fibrillation]

Both cardiac computed tomography (CT) and interventional electrophysiology (EP) have evolved considerably in recent years. Technical improvements in CT have significantly reduced the radiation dose in cardiac applications. This imaging technology plays an important role in preprocedural planning and guidance of the procedures in many EP centers worldwide. Furthermore, CT is the imaging modality of choice to diagnose relevant complications in ablation of atrial fibrillation, e.g. pulmonary vein stenosis or atrioesophageal fistula. In anatomically driven ablation procedures, such as balloon-based procedures in atrial fibrillation, detailed analysis of the relevant cardiac structures is absolutely crucial not only to reduce radiation exposure and procedure times but also to improve ablation success and to reduce the occurrence of complications. Current software applications enable 3-dimensional reconstruction of cardiac images and the integration into electroanatomical navigation systems. This article reviews the available evidence in this field and highlights recent developments in image guidance for ablation of atrial fibrillation.

Cryoballoon in atrial fibrillation ablation

Encouraging results of ablation therapy in patients with paroxysmal atrial fibrillation (AF) have prompted changes in professional practice guidelines. The most recent European guidelines have suggested that ablation might be offered as first-line therapy in selected patients. Cryoballoon ablation is a promising technology in interventional AF therapy. Two different sizes of the cryoballoon are currently available: a smaller (23 mm) and a larger (28 mm) balloon relative to the ostial diameter of the pulmonary veins. New tools, the circular mapping catheter and the use of intracardiac echocardiography, provide important periprocedural information. A meta-analysis of previous studies revealed outcome data with an AF-free survival rate of 72.83% at the 1-year follow-up in paroxysmal AF patients undergoing cryoballoon ablation. The most frequent, but reversible complication is phrenic nerve palsy with reported incidences up to 10%. All efforts must be taken to overcome this limitation, since the overall major complication rate tends to be lower in cryoballoon compared to radiofrequency ablation. In persistent AF, reported results in cryoballoon ablation had a limited success rate below 50% after a single procedure. A double balloon approach using both cryoballoon sizes might overcome some of the limitations in persistent AF. Prospective data and randomized studies are required. This article outlines the current status of cryoballoon technology in AF ablation therapy.

A continuous-wave optical parametric oscillator around 5-μm wavelength for high-resolution spectroscopy

We present a continuous-wave optical parametric oscillator (OPO) capable of high resolution spectroscopy at wavelengths between 4.8 μm and 5.4 μm. It is based on periodically poled lithium niobate (PPLN) and is singly resonant for the signal radiation around 1.35 μm. Because of the strong absorption of PPLN at wavelengths longer than 4.5 μm, the OPO threshold rises to the scale of several watts, while it produces idler powers of more than 1 mW and offers continuous tuning over 15 GHz. A supersonic jet spectrometer is used in combination with the OPO to perform measurements of the transient linear molecule Si(2)C(3) at 1968.2 cm(-1). Fifty rovibrational transition frequencies of the ν(3) antisymmetric stretching mode have been determined with an accuracy on the order of 10(-4) cm(-1), and molecular parameters for the ground and the v(3) = 1 state have been determined most precisely.

Enhanced upper tropical tropospheric COS: impact on the stratospheric aerosol layer

Carbonyl sulfide (COS) is considered to be a major source of the stratospheric sulfate aerosol during periods of volcanic quiescence. We measured COS at the tropical tropopause and find mixing ratios to be 20 to 50% larger than are assumed in models. The enhanced COS levels are correlated with high concentrations of biomass-burning pollutants like carbon monoxide (CO) and hydrogen cyanide (HCN). The analysis of backward trajectories and global maps of fire statistics suggest that biomass-burning emissions transported upward by deep convection are the source of the enhanced COS in the upper tropical troposphere.

Laparoscopic Sugiura procedure for conditioning of the blood stream through TIPSS in cirrhotic patient. Initial experience

The Sugiura procedure or the proximal gastric devascularisation was formerly the method of choice for esophageal varicose treatment in some patients. The frequency of this operation decreased stenting after the introduction of the transjugular portosystemic shunt into clinical practice. However this method performed laparoscopically could be useful as a complementary procedure when the blood stream through the transjugular intrahepatic portosystemic stent shunt is low and an esophageal rebleeding occurs. A 40-year old patient with hepatic cirrhosis and Child stage "B" was admitted to our clinic due to recurrent esophageal varicose bleeding. He underwent a transjugular intrahepatic portosystemic stent shunt implantation 27 months before the admission and the transjugular intrahepatic portosystemic stent shunt became occluded 3 times since implantation and was repeatedly revised. After admission a color Doppler of the stent was performed. The blood stream was 15 cm/s. The laparoscopic Sugiura procedure was performed after conditioning of the general status of the patient. Five ports were introduced 5 cm above the umbilicus, under the xiphoid, the right and left hypochondrium as well as the left mesogastrium. The dilated veins between the gastric coronary vein and esophagus and the short gastric veins on the great curvature were interrupted by means of an ultrasonic scalpel. The hiatus esophagus was opened, the esophagus was prepared up to the first pulmonal vein and the dilated esophageal veins were occluded with stitch ligatures. The operation was completed with Toupet partial fundoplication. The patient was followed 6 months after the surgery. No rebleeding occurred in this time period. Immediately after surgery the blood flow increased up to 97 cm/s; at 3 and 6 months follow-up the intrahepatic shunt remained open with 82 and 80 cm/s blood flow respectively. Laparoscopic Sugiura procedure performed as a complementary surgery after transjugular intrahepatic portosystemic stent shunt implantation increased blood perfusion through the intrahepatal constructed shunt and prevented its occlusion. However this initial experience has to be confirmed with a larger number of patients.

Corticotropin-releasing-hormone lacks analgesic properties: an experimental study in humans, using non-inflammatory pain

The antinociceptive potency of corticotropin-releasing-hormone (CRH) has been established in several animal studies in which both central and peripheral sites of action were considered. However, there have not yet been any experimental trials, besides one attempt using clinical dental pain demonstrating the potential analgesic properties of CRH in humans. For this reason, we studied the effect of CRH on experimental heat pain sensitivity in 18 healthy men, using a double-blind, cross-over and placebo-controlled design. A dose of 100 microg (i.v.) was chosen because of its well-known neuroendocrine effects in humans. The pain parameters assessed were, visual analog scale (VAS) ratings for pain intensity and pain unpleasantness, pain thresholds and scores for discrimination ability. To differentiate between a direct analgesic effect of CRH and indirect effects via evoked hormonal responses in the hypothalamic-pituitary-adrenocortical (HPA) system (beta-endorphin, ACTH, cortisol), CRH was applied with and without a pre-treatment with dexamethasone. In neither of the two conditions was there any systematic change in our pain parameters. This failure to find any evidence suggesting an analgesic action of CRH or of the subsequent hormones of the HPA system was obtained despite the fact that CRH produced clear neuroendocrine responses such as increases in the plasma concentration of beta-endorphin and cortisol. It is unclear whether the lack of analgesic action of CRH is due to its non-existence in humans, due to the use of a pain model which does not assess minute changes in pain sensitivity and does not trigger substantial inflammatory responses, or due to an insufficient dose of CRH.

Endocrinological and polysomnographic findings in Kleine-Levin syndrome: no evidence for hypothalamic and circadian dysfunction

Five subjects--four men, ages 17-28, and one woman, age 30--with Kleine-Levin syndrome were investigated during symptomatic (SP) and asymptomatic (ASP) periods. Investigations comprised medical history, MRI, polysomnography, 24-hour hormone profile of human growth hormone, melatonin, TSH, cortisol and FSH (in the woman only) assessed every 2 hours, actimetry, and sleep logs. Medical history confirmed presence of the three symptoms diagnostic of of typical Kleine-Levin syndrome: hypersomnia, excessive food intake, and psychic alteration. MRIs of the brain were normal in all patients. Symptomatic periods were triggered by unspecific events, such as infection, sleep deprivation, and alcohol. Polysomnography revealed low sleep efficiency during SPs, decreased amount of slow-wave sleep, and high frequency of stage shifts, indicating sleep fragmentation. Mean 24-hour growth hormone levels were reduced during the SPs in only two patients. Their hGH peaks were dissociated from slow-wave sleep during attacks and intervals, often occurring during wake time. Twenty-four-hour melatonin levels were increased during the SPs in all patients, but were lower in two patients during the nocturnal sleep period. Cortisol, TSH and FSH did not reveal important differences between attacks and intervals. Except for hGH, all hormones had normal circadian excretion during symptomatic and asymptomatic periods. Amplitude of nocturnal activity as assessed by actimetry was significantly increased in two patients, whereas amplitude of daytime activity was significantly reduced in three patients. Actimetry and sleep logs demonstrated prolonged sleep phases during SPs. Our investigation could confirm changes of sleep structure described in the literature. The neuroendocrinological findings could not confirm decreased hGH and cortisol and increased TSH levels during SPs, as previously reported in single cases by many authors. Endocrinological findings did not support an underlying circadian disorder in KLS.

Recognition signal for C-mannosylation of Trp-7 in RNase 2 consists of sequence Trp-x-x-Trp

C2-alpha-Mannosyltryptophan was discovered in human RNase 2, an enzyme that occurs in eosinophils and is involved in host defense. It represents a novel way of attaching carbohydrate to a protein in addition to the well-known N- and O-glycosylations. The reaction is specific, as in RNase 2 Trp-7, but never Trp-10, which is modified. In this article, we address which structural features provide the specificity of the reaction. Expression of chimeras of RNase 2 and nonglycosylated RNase 4 and deletion mutants in HEK293 cells identified residues 1-13 to be sufficient for C-mannosylation. Site-directed mutagenesis revealed the sequence Trp-x-x-Trp, in which the first Trp becomes mannosylated, as the specificity determinant. The Trp residue at position +3 can be replaced by Phe, which reduces the efficiency of the reaction threefold. Interpretation of the data in the context of the three-dimensional structure of RNase 2 strongly suggests that the primary, rather than the tertiary, structure forms the determinant. The sequence motif occurs in 336 mammalian proteins currently present in protein databases. Two of these proteins were analyzed protein chemically, which showed partial C-glycosylation of recombinant human interleukin 12. The frequent occurrence of the protein recognition motif suggests that C-glycosides could be part of the structure of more proteins than assumed so far.

C-Mannosylation of human RNase 2 is an intracellular process performed by a variety of cultured cells

C2-alpha-Mannosyltryptophan was discovered in RNase 2 from human urine, representing a novel way of attaching carbohydrate to a protein. Here, we have addressed two questions related to the biosynthesis of this modification: (i) is C-mannosylation part of the normal intracellular biosynthetic route, and (ii) how general is it, i.e. which organisms perform this kind of glycosylation? To answer the first question, RNase 2, which is identical to the eosinophil-derived neurotoxin, was isolated from intracellular stores of cultured human HL-60 cells. The enzyme was C-mannosylated at Trp-7, showing that the modification occurs intracellularly, before secretion of the protein. The second question was investigated by immunological and chemical analysis of RNase 2 purified from the supernatant of transiently transformed cells from different organisms. This revealed that C-mannosylation occurs in cells from man, green monkey, pig, mouse, and hamster. The observation that pig kidney cells contain the machinery for C-mannosylation of Trp-7 of human RNase 2 but that the homologous RNase from porcine kidney is not a substrate, since it does not contain a tryptophan at position 7, strongly suggests that C-mannosylated proteins other than RNase 2 exist. Recombinant RNase 2 isolated from insect cells, plant protoplasts, and Escherichia coli was not C-mannosylated. These results not only form the basis for further studies on the biochemical aspects of C-mannosylation but also have implications for the choice of cells for production of recombinant glycoproteins.

Interaction of the co-activator CBP with Myb proteins: effects on Myb-specific transactivation and on the cooperativity with NF-M

The oncoprotein v-Myb is a potent inducer of myeloid leukemias, and its cellular homolog c-Myb plays a crucial role in the regulation of hematopoiesis. Both proteins function as transcriptional regulators. We demonstrate that this function is mediated at least in part by the nuclear co-activator CREB binding protein (CBP). This protein interacts directly with both c-Myb and v-Myb and potentiates Myb-specific transcription as measured on the mim-1 promoter. In contrast, dominant negative mutants of CBP lead to repression, as does E1A, an antagonist of CBP function. Phosphorylation of c-Myb does not appear to be required for interaction with CBP, thus indicating that the binding may be constitutive. Furthermore, the C/EBP family member NF-M, which cooperates with c-Myb in transactivating the mim-1 promoter through an adjacent DNA binding site, is co-activated by CBP in a Ras-dependent manner. Not only the individual activities of c-Myb and NF-M are stimulated by CBP, but also their synergistic transcriptional function, while it is negatively regulated by dominant negative forms of CBP. These data suggest that CBP is recruited by both Myb proteins and NF-M and potentiates their transcriptional activity. We suggest that CBP can bridge between c-Myb and NF-M, thus providing an explanation for the strong synergism between these two proteins.

Casein kinase II phosphorylation site mutations in c-Myb affect DNA binding and transcriptional cooperativity with NF-M

Phosphorylation of c-Myb has been implicated in the regulation of the binding of c-Myb to DNA. We show that murine c-Myb is phosphorylated at Ser-11 and -12 in vivo and that these sites can be phosphorylated in vitro by casein kinase II (CKII), analogous to chicken c-Myb. An efficient method to study DNA binding properties of full-length c-Myb and Myb mutants under nondenaturing conditions was developed. It was found that a Myb mutant in which Ser-11 and -12 were replaced with Ala (Myb Ala-11/12), wild-type c-Myb, and Myb Asp-11/12 bound to the A site of the mim-1 promoter with decreasing affinities. In agreement with this finding, Myb Ala-11/12 transactivated better than wild-type c-Myb and Myb Asp-11/12 on the mim-1 promoter or a synthetic Myb-responsive promoter. Similar observations were made for the myeloid-specific neutrophil elastase promoter. The presence of NF-M or an NF-M-like activity abolished partially the differences seen with the Ser-11/12 mutants, suggesting that the reduced DNA binding due to negative charge at positions 11 and 12 can be compensated for by NF-M. Since no direct interaction of c-Myb and NF-M was observed, we propose that the cooperativity is mediated by a third factor. Our data offer two possibilities for how casein kinase II phosphorylation can influence c-Myb function: first, by reducing c-Myb DNA binding and thereby influencing transactivation, and second, by enhancing the apparent cooperativity between c-Myb and NF-M or an NF-M-like activity.

High affinity DNA binding of native full length c-Myb and differential proteolytic sensitivity of its N- and C-terminal domains

c-Myb is the prototype of a family of transcription factors characterised by a unique DNA binding domain. Previous analyses have concentrated on truncated versions of c-Myb as it has been very difficult to produce full length c-Myb. To overcome these difficulties we expressed full length c-Myb in HeLa cells using a recombinant vaccinia virus. Partially purified native full length c-Myb bound efficiently and specifically to DNA with a dissociation constant similar to that obtained with bacterially expressed DNA binding domains. No evidence was found for a negative effect of the leucine zipper on DNA binding. Furthermore the DNA binding domain was protease resistant in contrast to the transactivation and negative regulatory domains. Phosphorylation had no apparent effect on this differential protease sensitivity. The increased sensitivity of the C-terminal domain suggests a more open conformation, which may be relevant in the integration of signals and/or in protein-protein interactions.

Identification of 40 S ribosomal protein S6 phosphorylation sites in Swiss mouse 3T3 fibroblasts stimulated with serum

All of the phosphorylation sites in 40 S ribosomal protein S6 derived from serum-stimulated Swiss mouse 3T3 cells are found within a small cyanogen bromide (CNBr) peptide derived from the carboxyl terminus, Lys218-Lys249. Further cleavage of the CNBr peptide or the intact protein with endoproteinase Lys-C (endo Lys-C) generated a single phosphorylated peptide, implying that all the sites of phosphorylation resided either between Arg231 and Lys243 or between Arg231 and Lys249 if cleavage at Lys243 was blocked by phosphorylation at a nearby residue. To discern between these possibilities and to identify the phosphorylation sites, the protein was purified from serum-stimulated cells and cleaved with endo Lys-C, and the single endo Lys-C phosphorylated peptide was isolated and sequenced following conversion of all the phosphorylated serines to S-ethylcysteine. The results show that the phosphorylated peptide extends from Arg231 to Lys249 and that the sites of phosphorylation in vivo are Ser235, Ser240, Ser244, and Ser247.

Identification of the two major epidermal growth factor-induced tyrosine phosphorylation sites in the microvillar core protein ezrin

In response to epidermal growth factor (EGF) the microvillar core protein ezrin is phosphorylated transiently to a high level on tyrosine residues in human epidermoid carcinoma A431 cells. Here we report the identification of the tyrosine phosphorylation sites in ezrin using bacterially expressed protein as a substrate for in vitro phosphorylation with the EGF receptor. The two major phosphotyrosine-containing peptides observed in vivo were also phosphorylated in vitro. By secondary digestions and site-directed mutagenesis tyrosines 145 and 353 were identified as the sites of phosphorylation. One of the sites, Tyr145, lies in the N-terminal region of homology that is common to the band 4.1-talin-ezrin protein family. This tyrosine residue and its vicinal amino acids are conserved throughout the family members, including radixin, moesin, and the two phosphotyrosine phosphatases, PTP H1 and PTP MEG, but not in band 4.1 or talin. Tyr353 is localized within the alpha-helical domain of ezrin and comparison of the protein sequences reveals that this site is unique to ezrin.

Use of a triaxial magnetometer for respiratory measurements

We describe a triaxial magnetometer (Tri-mag) system, which consists of a transmitter, four sensors, a processing unit, and a personal computer (PC). The Tri-mag processing unit outputs the position of each sensor relative to the transmitter in three orthogonal coordinates, and this information is communicated to the PC. First, we demonstrated that within a defined octant of a sphere in which the center is the transmitter, we can measure radial distances with an accuracy of +/- 1 mm over a range extending from 10 to 70 cm from the transmitter. Second, we recorded the three-dimensional movement of sensors on the anterior and posterior surfaces of the chest wall during maximum voluntary ventilation in four normal men; all sensors were placed in the midsagittal plane of the body. Anterior sensors were located on the sternum at the level of the third intercostal space and at 2 cm above the umbilicus, whereas posterior sensors were located on the posterior spine at the same vertical levels as the anterior sensors. In all subjects the following was found. 1) Both anterior sensors moved anterior and cephalad during inspiration. The anterior thoracic sensor showed greater vertical than anteroposterior (A-P) movement, whereas the anterior abdominal sensor showed greater A-P than vertical movement. 2) Inspiration was associated with spinal extension, whereas expiration was associated with spinal flexion. Third, we used Tri-mag information to 1) measure tidal volume (VT) over a range extending from 500 ml to inspiratory capacity and 2) measure the change in end-expiratory lung volume (EELV) over a range extending from FRC to FRC plus a minimum of 1.5 liters. Our results indicate that greater than 96% of the changes in VT and greater than 82% of the changes in EELV can be accounted for by changes in A-P, vertical, and lateral dimensions of the chest wall.

Identification of the 40 S ribosomal protein S6 phosphorylation sites induced by cycloheximide

Injection of cycloheximide into rats induced the incorporation of up to 5 mol of phosphate/mol of liver 40 S ribosomal protein S6. Treatment of the protein with cyanogen bromide generated three phosphopeptides of Mr approximately 31,000, approximately 27,000, and approximately 4,000. Increasing the concentration of cyanogen bromide or redigestion of the larger peptides with additional cyanogen bromide converted almost all the phosphate-containing peptides into the Mr approximately 4,000 peptide. This peptide was isolated by reverse phase high pressure liquid chromatography, and the phosphoserines were identified by amino acid sequence analysis after being converted to S-ethyl-cysteine. The results show that the phosphate is incorporated into 5 of 7 serines clustered in a small 13-amino acid segment of the protein. By aligning the sequence of the Mr approximately 4,000 peptide with the recently published mouse cDNA sequence of S6, it is shown that this peptide resides at the carboxyl terminus of the protein. The relevance of the cycloheximide-induced sites of S6 phosphorylation to those stimulated by a variety of mitogens and oncogenes is discussed.