Hemagglutinating properties of apolipophorin III from the hemolymph of Galleria mellonella larvae

PURPOSE: Continuous lateral rotational therapy (CLRT) <40 degrees is a method of altering the position of the ventilated patient to help clear secretions from the lung. CLRT has not been shown to reduce the incidence of atelectasis or pneumonia but potentially offers a way to maximize positional drainage in these patients without producing adverse effects. Treatment intervention, bracketed by two (nonrotational) control periods. The purpose of this study was to determine if CLRT alters mucus transport in critically ill, intubated patients in the intensive care unit of a teaching hospital. MATERIALS AND METHODS: Thirteen critically ill, but stable, mechanically ventilated patients, mean age 74 years, were enrolled. They were placed supine on a Biodyne bed (KCI, San Antonio, Texas) and pressures in the cushions adjusted to patient's weight. A radiolabeled aerosol was delivered by bagging for 2 to 3 minutes and repeated measurements of lung radioactivity were obtained by imaging of the thorax over the following 3 hours. A 90-minute period of rotation of the bed, 30 degrees to either side was preceded and followed by two 45-minute control periods during which the patient remained supine and stationary on the bed. Coughs and suctions were recorded and blood gases obtained pre and post study. RESULTS: (1) The mucous clearance was slower than that reported in normal subjects and in ambulatory patients with COPD; (2) there was a slight, but not significant, increase in clearance during CLRT; (3) clearance reverted to pre-oscillation levels following therapy. Lack of significant effect may be attributed to too shallow an angle for rotation or too short an intervention period. CONCLUSION: Positional drainage effected by short duration CLRT did not appear to stimulate significant mucous removal from the lung in critically ill patients but also did not cause any adverse effects.     

Interhelical contacts are required for the helix bundle fold of apolipophorin III and its ability to interact with lipoproteins

Skin cancer is the most common human malignancy and is strongly associated with exposure to ultraviolet radiation (UVR). Several mechanisms including an increase in immediate early gene activation have been postulated to be involved in UVR-mediated carcinogenesis. We show that in a dose-dependent manner, UVR induces the expression of messenger RNA of a novel immediate early response gene, IEX-1, in human keratinocytes. Human keratinocytes and mouse fibroblasts transfected with an expression plasmid for IEX-1 grow at a faster rate than keratinocytes transfected with a similar plasmid that does not contain the IEX-1 sequence. IEX-1 protein is localized predominantly in the nucleus of keratinocytes by fluorescent antibody methods and by examination of the location of a green fluorescence IEX-1 fusion protein. Epidermal growth factor (EGF), a major mitogen of keratinocytes, and a tumor-promoting phorbol ester increase IEX-1 mRNA expression. IEX-1 may play a role in keratinocyte proliferation especially following UVR.     

Self-assembly as a route to one-dimensional lanthanum(III) salicylaldimine coordination polymer

The self-assembled formation of a one-dimensional lanthanum salicylaldimine coordination polymer was proved by the X-ray diffraction analysis of new lanthanum(III) nitrate complex containing N,N'-bis(salicylidene)-1,5-pentanediamine ligand (H₂L). It was obtained in situ in a one-step, metal-templated condensation of salicylaldehyde with 1,5-pentanediamine (cadaverine, biogenic polyamine) and characterized by microanalysis and spectroscopic (IR, ESI-MS, UV-Vis, and ¹H NMR) data. The [La(NO₃)₃(μ-H₂L)₂]∞ complex displayed 10-coordinate distorted bicapped dodecahedron geometry with unusual coordination pattern of undeprotonated salicylaldimines which acted as μ-bridging ditopic ligands using exclusively the oxygens as donor atoms with the nitrogen atoms not being involved in the coordination environment.     

Effect of locust poison on neuromembrane functional activity

1. The effect of locust poison (LP) on membrane excitability, chemosensitivity and Na-K pump activity was studied. 2. LP in a concentration of 10(-4) mg/ml has a potential independent blocking effect on neuromembrane excitability. 3. LP has an activation effect on Na-K pump-induced membrane hyperpolarization. 4. In a concentration higher than 10(-4) mg/ml, LP leads to a decrease in the acetylcholine-induced current and to an increase in this current after the washout of LP from the medium.     

高炉流程与电炉流程的环境性能比较

高炉-转炉流程和电炉流程是钢铁生产的两个主要流程。以某钢铁联合企业两个流程的实际数据为依据,利用生命周期评价方法比较转炉钢水、电炉钢水以及两个流程产品的环境负荷差别,并且分析钢铁联合企业两个流程的结构变化对企业环境负荷总量的影响。     

Expression of nitric oxide synthase isoforms (NOS II and NOS III) in adult rat lung in hyperoxic pulmonary hypertension

Breathing air with a high oxygen tension induces an inflammatory response and injures the microvessels of the lung. The resulting development of smooth muscle cells in these segments contributes to changes in vasoreactivity and increased pulmonary artery pressure. This in vivo study determines the temporal and spatial expression of endogenous endothelial nitric oxide synthase (NOS III) and inducible NOS (NOS II), important enzymes regulating vasoreactivity and inflammation, in the adult rat lung during the development of experimental pulmonary hypertension induced by oxidant injury. We analyzed the cellular distribution of these NOS isoforms, using specific antibodies, and assessed enzyme activity at baseline and after 1-28 days of hyperoxia (FIO2 0.87). The number of NOS III-immuno-positive endothelial cells increased early in hyperoxia and then remained high. By day 28, the relative number of these cells had increased from 40% in proximal vessels and 13-16% in distal alveolar vessels of the normal lung to 73-86% and 40-59%, respectively, in hyperoxia. Pulmonary alveolar macrophages (PAMs), normally few in number and only weakly immunopositive for NOS II or III in the normal lung, increased in number in hyperoxia and were strongly immunopositive for each isoform. These morphological data were supported by a temporal increase in total and calcium-independent NOS activity. Thus NOS expression and activity significantly increased in hyperoxia as pulmonary hypertension developed, and NOS III expression increased selectively in vascular endothelial cells, while both NOS isoforms were expressed by the PAM population. We conclude that this increase in expression of a potent vasodilator, an antiproliferative agent for smooth muscle cells, and an antioxidant molecule represents an adaptive response to protect the lung from oxidant-induced vascular and epithelial injury.     

Functional features of the locomotor muscles of the locust

The ultrastructure of muscle fibres, membrane electrical constants and synaptic membrane responses to microapplication of l-glutamate were investigated in longitudinal flight muscle and flexor tibia of Locusta migratoria migratorioides. The sarcomers of the flight muscle (fast) were smaller then those of the leg muscle (slow). The effective resistances (Ro) of the flight and leg muscles were (2.25 +/- 0.54)-10(5) omega and (1.65 +/- 0.57) X 10(5) omega. The specific resistance (Rm), space constant (tau) and time constant (lambda) in the same muscles were 774 +/- 106 omega-cm and 2583 +/- 119 omega-cm-2; 7.3 +/- 1.7 ms and 17.5 +/- 1.1 ms; 093 +/- 0.22 mm and 1.98 +/- 0.42 mm. When l-glutamate was applied iontophoretically to muscle fibres depolarization was recorded only in localized parts of the membrane. Microapplication of acetylcholine to intact and denervated muscle fibres of the slow leg muscle was uneffective. It is suggested that l-glutamic acid is the excitatory transmitter both in slow and fast insect muscles.     

The effects of SchistoFLRFamide on contractions of locust midgut

The goal of this study of 66 twins was to determine whether motor and cognitive functions assessed in early and middle childhood are vulnerable to perinatal hypoxic risk. In an earlier study of 76 infant and toddler twins (S. Raz, F. Shah, & C. Sander, 1996), the authors found that intrapair discrepancy on the Mental Developmental Index, but not on the Psychomotor Developmental Index, of the Bayley Scales of Infant Development was associated with discordance for perinatal hypoxic risk. The twins at lower risk outperformed their higher risk co-twins. In the present study the authors sought to establish in a new sample of preschool and school-age twins whether gaps in performance persist into early and middle childhood. Although the disparity in hypoxic risk between the co-twins was typically moderate, significant intrapair differences were observed on the measure of motor performance. Among the motor abilities examined, skills involving visually guided ballistic arm movements appeared to be the most vulnerable to perinatal risk.     

Interactions of a bicyclic analog of colchicine with beta-tubulin isoforms alphabeta(II), alphabeta(III) and alphabeta(IV)

In this study we have investigated the occurrence of cytochrome P450 isoforms and of related cytochrome P450 reductase in human hepatic stellate cells (hHSC), a type of cell having relevant roles in physiopathological conditions of the liver. By performing immunoblotting of hHSC microsomes and immunofluorescence analysis associated to confocal laser microscopy we detected only P450 enzymes belonging to the cytochrome P450 3A subfamily (CYP3A) as well as cytochrome P450 reductase. The presence of CYP3A was further indicated by detection of testosterone 6beta-hydroxylase activity in hHSC microsomes. Other important human P450 forms were either undetectable (CYP1A2, CYP2E1, CYP2C8/9/19 and CYP4A) or bearly detectable (CYP1A1) in hHSC. This is the first study showing existence of active cytochrome P450 isoforms in human HSC.     

Tropomyosin isoforms in intestinal mucosa: production of autoantibodies to tropomyosin isoforms in ulcerative colitis

BACKGROUND & AIMS: Autoantibodies against tropomyosins (TMs) have been reported in ulcerative colitis (UC). In this study the hTM isoforms (hTM1-5) present in intestinal epithelial cells and in smooth muscle were investigated, and the immunoreactivity against hTMs by immunoglobulin G (IgG) produced in vitro by colonic mucosal lymphocytes (LPMCs) from patients with UC, Crohn's disease (CD), and controls was examined. METHODS: TMs were extracted from colonic and jejunal epithelial cells and smooth muscle, and hTM isoforms were identified using isoform-specific monoclonal antibodies by enzyme-linked immunosorbent assay and transblot analysis. The immunoreactivity of IgG produced by colonic LPMCs was analyzed against the recombinant hTM isoforms. RESULTS: The major hTM isoforms present in colonic and jejunal epithelial cells are hTM5 and hTM4, whereas intestinal smooth muscle contains the hTM1-3 isoforms. The IgG synthesized in vitro by LPMCs from UC (n = 19) recognized hTM5 and hTM1, more significantly (P < 0.04 to <0.001) when compared with CD (n = 12) and controls (n = 17). However, IgG produced by LPMCs from CD did not show such anti-hTM reactivity. Mucosal anti-hTM IgG mainly belonged to the IgG1 subclass. CONCLUSIONS: Intestinal epithelial cells and smooth muscle have distinct hTM isoforms. Patients with UC, and not CD, show mucosal autoantibody response against hTM isoforms, particularly hTM5 and hTM1.     

Functional nonequivalence of Drosophila actin isoforms

We show that different Drosophila actin isoforms are not interchangeable. We sequenced the six genes that encode conventional Drosophila actins and found that they specify amino acid replacements in 27 of 376 positions. To test the significance of these changes we used directed mutagenesis to introduce 10 such conversions, independently, into the Act88F flight muscle-specific actin gene. We challenged these variant actins to replace the native protein by transforming germline chromosomes of a Drosophila strain lacking flight muscle actin. Only one of the 10 reproducibly perturbed myofibrillar function, demonstrating that most isoform-specific amino acid replacements are of minor significance. In order to establish the consequences of multiple amino acid replacements, we substituted portions of the Drosophila Act88F actin gene with corresponding regions of genes encoding other isoforms. Only one of five constructs tested engendered normally functioning flight muscles, and the severity of myofibrillar defects correlated with the number of replacements within the chimeric genes. Finally, we completely converted the flight muscle actin-encoding gene to one specifying a nonmuscle isoform, a change entailing a total of 18 amino acid replacements. Transformation of flies with this construct resulted in disruption of flight muscle structure and function. We conclude that actin isoform sequences are not equivalent and that effects of the amino acid replacements, while minor individually, collectively confer unique properties.     

Biosynthetic pathways of glycerol accumulation under salt stress in Aspergillus nidulans

Vitamin D is best known for its role in the regulation of calcium and bone metabolism. The effects of the biologically active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25 (OH)2D3), are mediated by binding to a specific intracellular vitamin D receptor, which is present in most tissues including the skin where it regulates the growth of epidermal cells. Calcipotriol is a synthetic analogue of 1,25(OH)2D3. In vitro the activity of calcipotriol is comparable to that of 1,25(OH)2D3. In vivo, however, the risk of calcipotriol changing calcium metabolism is greatly reduced. Animal studies have established that calcipotriol is 100-200 times less calcaemic than 1,25(OH)2-D3. This low calcaemic activity is mainly due to the rapid metabolism of calcipotriol. This pharmacological profile makes calcipotriol an ideal candidate for topical treatment of hyperproliferative skin disorders, such as psoriasis. This paper reviews the clinical experience with calcipotriol in psoriasis patients.     

Sex hormones differentially regulate isoforms of UDP-glucuronosyltransferase

PURPOSE: To investigate the role of sex hormones in the regulation of UDP-glucuronosyltransferase (UGT). METHODS: We examined liver from adult, prepubertal, gonadectomised and gonadectomised plus hormone replaced rats of both sexes. Immunohistochemistry and immunoblots were performed using a polyclonal UGT antibody to a number of family 1 and family 2 UGT isoforms. Northern blot analysis was performed utilising cDNA probes to family 1 and family 2 isoforms. RESULTS: Immunohistochemistry demonstrated variations in intensity and distribution of staining in the hormonally manipulated rats. Immunoblots showed variations in individual band intensity between rat groups. Immunoblots using a more specific antibody (anti-17 beta-hydroxysteroid UGT, which recognises UGT2B3 and UGT2B2) demonstrated marked differences between male and female rats and significant alterations after gonadectomy and testosterone replacement in the male rats. In northern analysis, UGT2B3 and 2B1 mRNA were significantly higher in adult males than females, and in prepubertal males compared to prepubertal females. In male rats, gonadectomy resulted in a 45-53% reduction in UGT2B3 and 2B1 levels respectively, which increased significantly with testosterone treatment to greater than normal adult levels. No change in UGT2B3 or 2B1 occurred after gonadectomy in females. In contrast, UGT1*1 mRNA tended to be higher in adult female and prepubertal female rats than in their male counterparts. In females, gonadectomy resulted in significant up-regulation of UGT1*1, while gonadectomy plus oestradiol treatment resulted in markedly reduced levels. UGT1*1 mRNA was not significantly altered by gonadectomy in males. CONCLUSIONS: This study demonstrates the differential effects of sex hormones on the expression of isoforms from the two phylogenetically distinct UGT families.     

Clinical chemistry of common apolipoprotein E isoforms

Apolipoprotein E plays a central role in clearance of lipoprotein remnants by serving as a ligand for low-density lipoprotein and apolipoprotein E receptors. Three common alleles (apolipoprotein E(2), E(3) and E(4)) give rise to six phenotypes. Apolipoprotein E(3) is the ancestral form. Common apolipoprotein E isoforms derive from nucleotide substitutions in codons 112 and 158. Resulting cysteine-arginine substitutions cause differences in: affinities for low-density lipoprotein and apolipoprotein E receptors, low-density lipoprotein receptor activities, distribution of apolipoprotein E among lipoproteins, low-density lipoprotein formation rate, and cholesterol absorption. Accompanying changes in triglycerides, cholesterol and low-density lipoprotein may promote atherosclerosis development. Over 90% of patients with familial dysbetalipoproteinaemia have apolipoprotein E(2)/E(2). Apolipoprotein E(4) may promote atherosclerosis by its low-density lipoprotein raising effect. Establishment of apolipoprotein E isoforms may be important for patients with diabetes mellitus and several non-atherosclerotic diseases. Apolipoprotein E phenotyping exploits differences in isoelectric points. Isoelectric focusing uses gels that contain pH 4-7 ampholytes and urea. Serum is directly applied, or prepurified by delipidation, lipoprotein precipitation or dialysation. Isoelectric focusing is followed by immunofixation/protein staining. Another approach is electro- or diffusion blotting, followed by protein staining or immunological detection with anti-apolipoprotein E antibodies and an enzyme-conjugated second antibody. Apolipoprotein E genotyping demonstrates underlying point mutations. Analyses of polymerase chain reaction products are done by allele-specific oligonucleotide probes, restriction fragment length polymorphism, single-stranded conformational polymorphism, the primer-guided nucleotide incorporation assay, or denaturating gradient gel electrophoresis. Detection with primers that either or not initiate amplification is performed with the amplification refractory mutation system. Disparities between phenotyping and genotyping may derive from isoelectric focusing methods that do not adequately separate apolipoprotein E posttranslational variants, storage artifacts or faint isoelectric focusing bands.     

Biosynthetic growth hormone in the treatment of low stature in Turner syndrome

BACKGROUND AND STUDY AIMS: The presumptive diagnosis of Candida esophagitis has been included in the Centers for Disease Control (CDC) case definition for full-blown AIDS since 1987. Endoscopic examination should be reserved for patients showing symptoms despite treatment. The purpose of this study was to assess the degree of diagnostic accuracy of the CDC presumptive clinical criteria and to determine the usefulness of upper digestive endoscopy in the diagnosis of Candida esophagitis in patients infected with HIV-1, with and without a previous AIDS-defining event. PATIENTS AND METHODS: A total of 144 HIV-1 infected patients who had undergone an upper digestive endoscopy were studied retrospectively. To determine the risk and the predictive value of the clinical markers, only the 84 patients without prior antimycotic therapy were included. RESULTS: Of the 84 patients without previous treatment, 34 (41%) had a history of an AIDS-defining illness. Candida esophagitis was found on endoscopy in 11 of the AIDS and 28 of the non-AIDS cases. Oral thrush, either alone (relative risk [R.R.] 9.4; 95% C.I. 2.4-36.4; p < 0.01; positive predictive value [PPV] 82%) or in combination with esophageal symptoms (R.R. 7.4; 95% C.I. 2.5-21.9; p < 0.01; PPV 89%), was a reliable marker of Candida esophagitis only in patients with a previous AIDS-defining event. The diagnostic value of the CDC presumptive pattern was confirmed by a multivariate analysis after controlling for the CD4 cell count (R.R. 9.3; 95% C.I. 2.3-25.3; p < 0.01). On the other hand, in HIV-1 positive patients without a previous AIDS-defining event, the diagnostic accuracy of oral candidiasis, either alone (R.R. 1.4; 95% C.I. 0.8-2.4; p n.s.; PPV 64%) or in combination with esophageal symptoms (R.R. 1.1; 95% C.I. 0.7-1.8; p n.s.; PPV 60%), was too low to allow a reliable diagnosis of Candida esophagitis. CONCLUSIONS: A presumptive diagnosis of Candida esophagitis on the basis of the CDC clinical criteria is a valid diagnostic method only in HIV-1 infected patients with a previous diagnosis of full-blown AIDS. Upper digestive endoscopy should be performed in symptomatic patients with no history of an AIDS-defining illness, especially if the diagnosis of esophageal candidiasis is important for surveillance purposes.     

Reconfiguration of the respiratory network at the onset of locust flight

Reconfiguration of the respiratory network at the onset of locust flight. J. Neurophysiol. 80: 3137-3147, 1998. The respiratory interneurons 377, 378, 379 and 576 were identified within the suboesophageal ganglion (SOG) of the locust. Intracellular stimulation of these neurons excited the auxillary muscle 59 (M59), a muscle that is involved in the control of thoracic pumping in the locust. Like M59, these interneurons did not discharge during each respiratory cycle. However, the SOG interneurons were part of the respiratory rhythm generator because brief intracellular stimulation of these interneurons reset the respiratory rhythm and tonic stimulation increased the frequency of respiratory activity. At the onset of flight, the respiratory input into M59 and the SOG interneurons was suppressed, and these neurons discharged in phase with wing depression while abdominal pumping movements remained rhythmically active in phase with the slower respiratory rhythm (Fig. ). The suppression of the respiratory input during flight seems to be mediated by the SOG interneuron 388. This interneuron was tonically activated during flight, and intracellular current injection suppressed the respiratory rhythmic input into M59. We conclude that the respiratory rhythm generator is reconfigured at flight onset. As part of the rhythm-generating network, the interneurons in the SOG are uncoupled from the rest of the respiratory network and discharge in phase with the flight rhythm. Because these SOG interneurons have a strong influence on thoracic pumping, we propose that this neural reconfiguration leads to a behavioral reconfiguration. In the quiescent state, thoracic pumping is coupled to the abdominal pumping movements and has auxillary functions. During flight, thoracic pumping is coupled to the flight rhythm and provides the major ventilatory movements during this energy-demanding locomotor behavior.     

Identification of murine p120 isoforms and heterogeneous expression of p120cas isoforms in human tumor cell lines

Heat stress is a common problem for cattle. General consequences of heat stress include increased body temperatures and reduced feed intakes. As a measure of heat stress, core body temperatures of unshaded feedlot steers (crossbred Bos taurus) were monitored from mid-June to early November in Nebraska using transmitters implanted in the peritoneum of 10 steers (initially 10 mo of age). Steers were fed at 0630 and 1430 using a finishing diet of 1.52 NEg Mcal/kg with 13% protein and 4% roughage per day and housed in two open lots with stocking densities of 15.2 or 19.3 m2/steer. Core body temperatures, ambient temperature, relative humidity, and wind speed were measured at 3-min intervals and mathematically filtered to produce 120 readings/ d. For 94 usable daily records, body temperature means (39.04 +/- .12 degrees C), maxima (39.89 +/- .21 degrees C at 1836 +/- .73 h), minima (38.33 +/- .29 degrees C at 0823 +/- .38 h), and patterns were similar among steers. As daily maximum ambient temperatures increased, minimum body temperatures decreased slightly (.04 degree C per 5 degrees C; P < .01). After daily maximum ambient temperatures reached a threshold of 25.6 degrees C, daily maximum body temperatures increased linearly with maximum ambient temperatures (.42 degree C per 5 degrees C; P < .01). Sharp peaks in body temperature were often seen in the late evening (approximately 2200) after ambient temperature had decreased to well below maximum values. These evening peaks occurred on an average of 25% of the days, had amplitudes ranging from .7 to 3.5 degrees C relative to mean daily temperatures and lasted for 1.5 h. From a practical standpoint, we suggest that producers monitor meteorological forecast of peak ambient temperatures and make special efforts, such as spraying animals, when exceptionally hot weather is predicted.     

Two isoforms of glutamate decarboxylase: why?

Adults express two isoforms of glutamate decarboxylase (GAD), GAD67 and GAD65, which are encoded by different independently regulated genes, a situation that differs from that of other neurotransmitters. In this article, J-J. Soghomonian and David Martin review current knowledge on the differences between these two isoforms. Both isoforms are present in most GABA-containing neurones in the CNS, but GAD65 appears to be targeted to membranes and nerve endings, whereas GAD67 is more widely distributed in cells. Both forms can synthesize transmitter GABA, but GAD67 might preferentially synthesize cytoplasmic GABA and GAD65 might preferentially synthesize GABA for vesicular release. Several lines of evidence suggest that the two forms have different roles in the coding of information by GABA-containing neurones.     

Heterodimerization preferences of thyroid hormone receptor alpha isoforms

Thyroid hormone receptors (TRs) are members of the steroid hormone receptor superfamily and are encoded by two different genes, alpha and beta. Three isoforms (alpha 1, alpha 2, and alpha 3) are created by alternative splicing of the TR alpha gene. In TR alpha 2 and alpha 3, the distal half of the putative dimerization domain is disrupted and the carboxy terminus of the protein is substituted with different amino acids. To evaluate the properties of these alterations in the dimerization region, DNA binding and dimerization of TR alpha isoforms were studied by electrophoretic mobility shift assays. TR alpha 1 formed a monomer or a homodimer on certain thyroid hormone responsive elements (TREs), whereas TR alpha 2 and alpha 3 did not bind effectively to any of the TREs studied. TR alpha 1 formed a heterodimer with 9-cis retinoic acid receptor alpha (RXR alpha) on all TREs studied. Although TR alpha 2 did not bind as a homodimer, it did bind as a heterodimer with RXR alpha to DR4 and MHC-TRE. TR alpha 3 bound as a heterodimer to a broader repertoire of TREs, including DR4, MHC, ME, and F2-TRE. These results indicate that the alterations in the dimerization region in TR alpha 2 and alpha 3 abrogated homodimer binding, but differentially affected heterodimerization with RXR alpha on various TREs.