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The nucleotide sequence of the RNA1 of Patchouli mild mosaic virus (PatMMV) has been determined. It contains 5,957 nucleotides excluding the 3′-terminal poly(A) tail and contains a single long open reading frame (ORF) of 5,613 nucleotides extending from nucleotide 235 to 5847. The predicted polyprotein encoded by the long ORF is 1,870 amino acids in length with a molecular weight of 210 kD. The conserved residues of RNA-dependent RNA polymerase, cysteine protease, purine NTP-binding domain and a cofactor for viral protease are present in a 210-kD polyprotein. As PatMMV RNA showed high sequence identity (81–97%) with BBWV-2 RNA, PaMMV may be one strain of BBWV-2.

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Surfactant protein B (SP-B) is detected in the airways as a sulfhydryl-dependent dimer (M(r) approximately 16,000). To test the hypothesis that formation of homodimers is critical for SP-B function, the cysteine residue reported to be involved in SP-B dimerization was mutated to serine (Cys(248) --> Ser) and the mutated protein was targeted to the distal respiratory epithelium of transgenic mice. Transgenic lines which demonstrated appropriate processing, sorting, and secretion of human SP-B monomer were crossed with SP-B +/- mice to achieve expression of human monomer in the absence of endogenous SP-B dimer (hSP-B(mon), mSP-B-/-). In two of three transgenic lines, hSP-B(mon), mSP-B-/- mice had normal lung structure, complete processing of SP-C proprotein, well formed lamellar bodies, and normal longevity. Pulmonary function studies revealed an altered hysteresis curve for hSP-B(mon), mSP-B-/- mice relative to wild type mice. Large aggregate surfactant fractions from hSP-B(mon), mSP-B-/- mice resulted in higher minimum surface tension in vitro compared with surfactant from wild type mice. Surfactant lipids supplemented with 2% hSP-B monomer resulted in slower adsorption and higher surface tension than surfactant with 2% hSP-B dimer. Taken together, these data indicate a role for SP-B dimer in surface tension reduction in the alveolus.

Surfactant protein D (SP-D) is a 43-kDa member of the collectin family of collagenous lectin domain-containing proteins that is expressed in epithelial cells of the lung. The SP-D gene was targeted by homologous recombination in embryonic stem cells that were used to produce SP-D (+/-) and SP-D (-/-) mice. Both SP-D (-/-) and SP-D (+/-) mice survived normally in the perinatal and postnatal periods. Whereas no abnormalities were observed in SP-D (+/-) mice, alveolar and tissue phosphatidylcholine pool sizes were markedly increased in SP-D (-/-) mice. Increased numbers of large foamy alveolar macrophages and enlarged alveoli were also observed in SP-D (-/-) mice. Phospholipid composition was unaltered in SP-D (-/-) mice, but surfactant morphology was abnormal, consisting of dense phospholipid membranous arrays with decreased tubular myelin. The pulmonary lipoidosis in the SP-D (-/-) mice was not associated with accumulation of surfactant proteins B or C, or their mRNAs, distinguishing the disorder from alveolar proteinosis syndromes. Surfactant protein A mRNA was reduced and, SP-A protein appeared to be reduced in SP-D (-/-) compared with wild type mice. Targeting of the mouse SP-D gene caused accumulation of surfactant lipid and altered phospholipid structures, demonstrating a previously unsuspected role for SP-D in surfactant lipid homeostasis in vivo.

The complete nucleotide sequence and the genome organization of the RNA 2 of a patchouli mild mosaic virus (PaMMV) was determined. The sequence consists of 3591 nucleotides and contains a single long open reading frame sufficient to code for 118K protein. Three proteins of 52 K, 44 K and 22 K could be encoded by the PaMMV RNA 2 genome. Our analysis of the N-terminal sequences of two species of coat protein (CP) allowed precise location of the CP cistrons within the polyprotein. 44 K and 22 K proteins are the coat proteins. The positions of the cleavage sites are Gln/Ala between 44 K and 22 K coat proteins and Gln/Gly between 52 K and 44 K proteins. Comparison of PaMMV RNA 2 with comoviral and nepoviral RNA 2 showed no sequence similarity. These results as well as previous serological studies strongly suggest that PaMMV is a member in the genus Fabavirus.

The combustion process in spark–ignition engines is simulated using a multi–dimensional simulation method similar to that of Ahmadi–Befrui et al. The turbulence characteristics are described by the k–ε model that is modified by taking into consideration the results of in–cylinder measurements. An empirical constant for the combustion submodel is determined by optimum matching of the predicted cylinder–pressure courses with the measured ones. Calculations reasonably reproduce the measured course of combustion. Furthermore, a discussion is given on the effects of induction swirl and fuel–air equivalence ratio on combustion process.

Omeprazole is a potent antisecretory drug that acts by inhibiting the gastric proton pump. In the present study, we have observed the effects of this drug on gastrointestinal mucosal perfusion, oxygenation, and hexosamine generation in humans. Sixteen healthy volunteers were included. Gastrointestinal mucosal perfusion and oxygenation (duodenum, antrum, and corpus) were assessed by laser-Doppler flowrnetry and reflectance spectrophotometry. Biopsy specimens were also taken from each location to determine hexosamine content as a quantitative indicator of mucus generation. In addition, serum gastrin level was measured. After baseline data were obtained, subjects were randomly assigned to receive 20 mg of oral omeprazole once daily for 7 days (n=8) or placebo (n=8). All measurements were performed again after double-blinded drug administration. No effect was found after placebo administration. In contrast, omperazole administration significantly increased serum gastrin level (p<.05), suggesting an inhibition of acid secretion. However, this drug did not alter either laser-Doppler signal or oxygen saturation at each location. In addition, no change in mucosal hexosamine content was observed at each location. We conclude that oral omeprazole, despite its well-established antisecretory effect, has no adverse effect on the mucosal defense in humans.

The function of the 102-amino acid C-terminal propeptide of surfactant protein B (SP-B) was analyzed by characterizing the phenotype associated with loss of expression of this peptide domain in transgenic mice. A construct encoding the signal peptide, N-terminal propeptide, and mature peptide of human SP-B (hSP-BDeltac) was cloned under the control of the 3.7-kilobase human SP-C promoter and injected into fertilized eggs of the FVB/N mouse strain. Founder mice expressing the hSP-BDeltac transgene were bred with heterozygous SP-B knockout mice (SP-B +/-). Offspring containing the transgene and one allele of mouse SP-B were identified and subsequently crossed to generate a transgenic line that expressed SP-BDeltac in a null background (SP-B(-/-)/hSP-BDeltac(+/+)). Expression of hSP-BDeltac in SP-B(-/-) mice was restricted to type II cells and resulted in a 2-fold increase in mature SP-B relative to wild type littermates. These mice survived without any evidence of respiratory problems and had normal lung function, normal alveolar surfactant phospholipid pool sizes, and typical tubular myelin indicating that the 102-residue C-terminal propeptide of SP-B is not required for normal structure and function of extracellular surfactant. However, proteolytic processing of the SP-C proprotein was perturbed resulting in the accumulation of a processing intermediate, Mr = 11,000, similar to the phenotype detected in SP-B(-/-) mice; furthermore, lamellar bodies in type II cells of SP-B(-/-)/hSP-BDeltac(+/+) mice were much larger than in the wild type animal and saturated phosphatidylcholine content in lung tissue was significantly increased although the incorporation of choline into saturated phosphatidylcholine was normal. Collectively, these results demonstrate a role for the C-terminal propeptide of SP-B in SP-C proprotein processing and the maintenance of lamellar body size. The C-terminal propeptide may be an important determinant of intracellular surfactant pool size.

A 100kD microtubule-bundling protein dynamin was phosphorylated in vitroby cdc2 kinase to ∼1 mol of phosphate / mol of dynamin at a serine residue. These phosphorylations of dynamin greatly reduced its binding ability to microtubules.

The present experiments determined if increases in renal reabsorptive capacity during the transition from fetal to neonatal life are gestation dependent. Renal function was studied in chronically-catheterized fetal lambs (133 +/- 1 days; term, 145-150 days). Additionally, renal function was studied in anaesthetized, ventilated, caesarean-delivered preterm lambs (109-139 days gestation) and term lambs (148 days gestation), and in 2-day-old spontaneously-delivered term lambs. Newborns < or = 120 days old received surfactant to facilitate ventilation and maintenance of physiologic blood gases. Two hours after caesarian delivery, urine osmolality, urine flow, glomerular filtration rate (GFR), and fractional sodium excretion (FENa) values were similar for all gestations. Relative to fetal values, caesarean-delivered newborn renal values included lower urine flow rates (0.20 +/- 0.03 v. 0.05 +/- 0.01 mL min-1 kg-1), higher urine osmolalities (118 +/- 15 v. 422 +/- 16 mOsmol kg-1 H2O), and no differences in GFR or FENa. Relative to caesarean-delivered newborns, 2-day newborn renal function included higher values for GFR (0.7 +/- 0.1 v. 3.0 +/- 0.1 mL min-1 kg-1) and urine osmolality (724 +/- 32 mosmol kg-1 H2O), and lower FENa (7.0 +/- 1.5 v. 0.2 +/- 0.02%), and urine flow (0.005 +/- 0.003 mL min-1 kg-1). The 132- and 139-day animals were ventilated for 5 h and 10 h respectively; the only functional change at 10 h was a decrease in FENa (7.0 +/- 1.5 v. 2.8 +/- 0.1%). It is concluded that: (1) relative to fetal animals, renal adaptive responses in anaesthetized, ventilated newborns begin within 2 h following caesarian delivery; (2) initial adaptive responses are not gestation dependent after 109 days; and (3) the combined effects of ventilation and/or anaesthesia delay postnatal renal adaptations for at least 10 h after birth.

In order to obtain a better understanding of the behavior of aerosols and SO2 in the longrange transport through a marine boundary layer, a simple box-model is applied to the evaluation of the residence times of the species from the concentrations of gases and aerosols measured simulataneously on two islands in the West Pacific Ocean in the north-west monsoon. For Aitken and large particles, the residence time is varied from 3.7 to 7.4 days depending on the particle size, and their flux to the sea is equal to or slightly smaller than that of the free atmosphere. The residence time of giant particles is about one day and their flux to the sea is three times larger than that of the free atmosphere. The residence time of SO2 is 15 hr, and the relative SO2 mass flows of the deposition to the sea, of the diffusion to the free atmosphere and of the transformation to SO42- are approximately 4, 1 and 1, respectively.

Comparison of the nucleotide sequences of the DNAs of bean golden mosaic virus (BGMV), tomato golden mosaic virus (TGMV) and cassava latent virus (CLV) revealed a fairly close relationship between BGMV DNA1, TGMV DNA1, and CLV DNA1 and a comparatively distant relationship between BGMV DNA2, TGMV DNA2, and CLV DNA2. The 200-base region common to the two DNAs of each virus had little sequence homology, except for a highly conserved 33–36 base sequence potentially capable of forming a stable hairpin structure. All the potential coding regions in the BGMV DNAs had counterparts in the TGMV and CLV DNAs suggesting an overall similarity in genome organization but two potential coding regions in the BGMV DNAs had no counterparts in the TGMV DNAs. The most highly conserved ORFs, BGMV 1R1, TGMV 1R1, and CLV 1R1, are the putative genes for the coat proteins of BGMV, TGMV, and CLV. BGMV 1R1 has 91.9% and 71.6% homology with respect to TGMV and CLV. The ORFs (BGMV 1L1; CLV 1L1; TGMV 1L1) and the two smaller overlapping ORFs (BGMV 1L2, 1L3; TGMV 1L2, 1L3; CLV 1L5, 1L3) are conserved in the three viruses. BGMV 2R1 and BGMV 2L1 have higher homology with respect to TGMV but not with respect to 2R1 and 2L1 in CLV. From this study we conclude that BGMV is more closely related to TGMV than CLV.

The influence of left-right ductal shunting on early hemodynamic responses, namely left ventricular performance, contractility, and systemic perfusion was evaluated in nine preterm lambs (120 days gestational age) treated with surfactant. Blood gases were maintained in the physiological range using mechanical ventilation; hemodynamic and blood flow measurements (radionuclide labeled microspheres) were obtained before and after occlusion of the patent ductus arteriosus with a catheter balloon. The mean left-right ductal shunt before occlusion (1.2 h postnatal age) was 59 ± 11 SD. Left ventricular output was increased in all lambs with PDA (pre 306 ± 106 veruspost 155 ± 31 ml/min/kg; p<0.001); effective systemic blood flow and organ blood flows did not change. The left ventricle end-diastolic volume was increased in all and decreased following ductal occlusion (pre 2.0 ± 0.4 veruspost 1.5 ± 0.2 ml/kg; p<0.01). Cardiac rate, ejection fraction, and contractility (peak dP/dt) did not change. Right-left ductal shunting was not detected in six similarly treated lambs. Thus, during the 1st h of life the hemodynamic profile of preterm lambs with patent ductus arteriosus was characterized by large magnitude left-right shunt and a “high” cardiac output state sufficient to maintain unchanged systemic perfusion. The increased left ventricle output was accomplished by increasing end-diastolic volume (Frank-Starling mechanism), but left ventricle contractility remained unchanged. We speculate that the preterm left ventricle may be unable to sustain the high level of pump performance and contractility required to compensate for the ductal “steal” of systemic blood flow.

Double-stranded RNA was isolated from tobacco leaves and characterized in terms of base composition, density, and nuclease resistance. Although its role in the plant's physiology is not clear, evidence was adduced that it is the product of the RNA-dependent RNA polymerase previously shown to occur in this and other plants. The fact that twice as much fully than partially double-stranded RNA appears to be made favors a regulatory role for the double-stranded RNA rather than a transcriptional intermediate role.

ABSTRACT.: The influence of left-right ductal shunting on early hemodynamic responses, namely left ventricular performance, contractility, and systemic perfusion was evaluated in nine preterm lambs (120 days gestational age) treated with surfactant. Blood gases were maintained in the physiological range using mechanical ventilation; hemodynamic and blood flow measurements (radionuclide labeled microspheres) were obtained before and after occlusion of the patent ductus arteriosus with a catheter balloon. The mean left-right ductal shunt before occlusion (1.2 h postnatal age) was 59 ± 11% SD. Left ventricular output was increased in all lambs with PDA (pre: 306 ± 106 verus post: 155 ± 31 ml/min/kg; p < 0.001); effective systemic blood flow and organ blood flows did not change. The left ventricle end-diastolic volume was increased in all and decreased following ductal occlusion (pre: 2.0 ± 0.4 verus post: 1.5 ± 0.2 ml/kg; p < 0.01). Cardiac rate, ejection fraction, and contractility (peak dP/dt) did not change. Right-left ductal shunting was not detected in six similarly treated lambs. Thus, during the 1st h of life the hemodynamic profile of preterm lambs with patent ductus arteriosus was characterized by large magnitude left-right shunt and a “high” cardiac output state sufficient to maintain unchanged systemic perfusion. The increased left ventricle output was accomplished by increasing end-diastolic volume (Frank-Starling mechanism), but left ventricle contractility remained unchanged. We speculate that the preterm left ventricle may be unable to sustain the high level of pump performance and contractility required to compensate for the ductal “steal” of systemic blood flow.

To assess the magnitude of reutilization of surfactant phosphatidylcholine, 68 3-day-old rabbits were injected intratracheally with a trace dose of [3H]choline-labeled surfactant mixed with [14C]palmitate-labeled synthetic dipalmitoylphosphatidylcholine. After timed kills we measured the total phosphatidylcholine associated counts/min in whole lung and alveolar wash and the specific activities of phosphatidylcholine in the alveolar wash, lamellar bodies, and microsomes isolated from the lung of each rabbit. Using a modification of the compartment analysis of Skinner et al. (Skinner, S. M., Clark, R. E., Baker, N., and Shipley, R. A. (1959) Am. J. Physiol. 196, 238-244), we found that surfactant phosphatidylcholine was reutilized with greater than 90% efficiency. The turnover time of the alveolar wash phosphatidylcholine was estimated to be 10.1 h and 9.3 h as measured by the 3H and 14C labels, respectively. From the ratios of alveolar wash-associated natural to synthetic phosphatidylcholine specific activities and from similar ratios obtained in 30 additional rabbits using [14C]choline-labeled natural surfactant and [3H]choline-labeled dipalmitoylphosphatidylcholine, we showed that phosphatidylcholine was reutilized intact rather than as component parts. Within 6 h of injection, the synthetic dipalmitoylphosphatidylcholine functioned metabolically as that administered in the form of natural surfactant.

Gemini viruses1,2, a recently discovered group of plant viruses, are the only viruses containing circular single-stranded DNA (ssDNA) found in eukaryotic organisms. Their ssDNA, which is less than half the size (molecular weight (Mr) 7–8 × 105) (refs 3–6) of that of other ssDN A viruses7,8, is the smallest yet found in autonomously replicating viruses. Geminivirus DNA is encapsidated in paired isometric particles whose monomer units measure ∼18 nm. This unique capsid morphology was accounted for by an early hypothesis of a functionally divided genome. Among the RNA plant viruses, there are several groups that carry necessary genetic information on more than one nucleic acid species. In the case of geminiviruses, two nucleic acid components were postulated to be carried in each paired particle9,10. Analyses of the physical composition of geminiviruses showed, however, that there is only one DNA molecule in each paired particle6,11,12. We have now investigated the DNA of a geminivirus using restriction endonucleases and a biological assay of infectivity and report here evidence for a divided genome in bean golden mosaic virus (BGMV). Two different nucleotide sequences are found and both seem to be required for infectivity.

Several properties of RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6) active fractions obtained from tobacco plants, be they uninfected, infected with tobacco mosaic virus, or infected with tobacco necrosis virus, were compared. By the seven criteria tested, the RNA-dependent RNA polymerase from these three sources behaved the same, although its activity is greatly but variably stimulated by the two virus infections. It thus appears probable that these two viruses do not code for this enzyme, but rely for their replication on their ability to stimulate production of a host enzyme. The conclusion that cells contain RNA replicating capability represents a modification of the central dogma of molecular biology.

To determine the incidence of hyperprolactinemia and prolactinoma without symptoms in men, the serum levels of prolactin were measured in 4803 men. Of these, 14 had hyperprolactinemia with prolactin level of over 50 ng/ml, and 3 had prolactin levels of more than 500 ng/ml. Of these 3 subjects, 2 were found to have pituitary prolactinoma by computed tomograph scanning and surgery, the other subject, who was highly suspected to have prolactinoma, refused further examinations. The serum prolactin levels of 51–100 ng/ml in 11 subjects may have been induced by drugs (sulpiride) or unknown factors. The present survey suggests that the incidence of prolactinoma in men in the general population might be estimated to be 1:1600, and that mass screening is useful for early diagnosis of asymptomatic prolactinoma.

We studied 10 premature lambs with RDS to assess pulmonary blood flow (PBF) and protein leak distribution relative to aerated and atelectatic lung volumes. The lambs were delivered by C-section, intubated, paralyzed and ventilated so as to maintain normal blood gases. At 3.5 hrs, 125I ovalbumin (OA) was injected into an umbilical artery. At 4 hrs, radiolabeled microspheres were injected into the right ventricle to assess PBF distribution. The animals were sacrificed at 4 hrs of age, the lungs were removed, and divided into approximately 60 1 gm pieces, separating the lung into 3 categories: collapsed (C), partially aerated (P), and fully aerated (A). Each piece was assayed for 125I and microspheres. Results: 1) There was more flow to A than C regions, p<.01 in 8/10 lambs. By weight A was 36.7-70.1% (56.1%) and C was 14.9-52.1 (26.4%), while the % of total blood flow was 49.6-77.7% (64.0%) and 8.0-39.1% (19.2%), respectively. Without autoregulation there would be a mean shunt of 26.4% instead of the 19.2% measured, which could make a significant difference in the FiO2needed to maintain normal oxygenation. Including P with C does not significantly change these results. 2) There was a relatively uniform protein leak throughout the lung but more in A than C in 4/5 animals that received OA, p<.05. 3) There was no correlation between blood flow and protein leak. Conclusions: Premature lambs with RDS have a small but significant ability for autoregulation of PBF, and intravascular protein tends to leak more in A than C regions.

We injected 16 pregnant does with .1 mg/kg·day betamethasone (B) or vehicle (C) on the 2 days before C-section at day 27. The newborns were tracheostomized and randomly treated with normal saline (Sal), 5, 15, 30, or 50 mg/kg of rabbit surfactant (SA). They were then ventilated for 10 min with a ventilator-plethysmograph at tidal volumes of 12-15 ml/kg. After lung collapse, air pressure-volume inflation (Vi) and deflation (Vd) curves were measured from 0 (V0) to 35 cm H2O (V35) with volumes expressed as mean±SEM for ml/g dry lung wt and lung stability index (LSI) as (2V5±V10-3V0)/(2V35-2V0).There were significant differences for Vi35, Vd35, Vd15and compliance between C and B at each dose (p<.01). The similarity of values for LSI between C and B showed that the steroid effect was not related to changing surface tension. Steroids have a threshold and synergistic effect on surfactant at low doses.

Several studies have demonstrated RU of NS PC in developing and adult R. The magnitude of RU in adult R has not been determined. We injected 87 1 kg R with two solutions simultaneously. [14C]palmitate was given IV and a solution of [3H]choline labeled NS plus [32P]dipalmitoylPC (DPC) was injected intratracheally (IT). R were sacrificed from 10 min to 72 hrs after injection. From each R we collected a complete alveolar wash (AW) and isolated a lamellar body (LB) fraction. We measured total [3H]PC and [32P]PC recovered in the AW and [14C]PC specific activity (SA) in the AW and in LB. From curves of [14C]PC SA in the LB and the AW vs time, we calculated the flux of PC from the LB into the AW (PC flux) and the turnover times (Tt) for alveolar PC (Tt=total AW PC/PC flux). A computer generated equation describing the total AW [3H]PC vs time was obtained and used to independently calculate the PC flux, the Tt, the % RU of NS PC and the LB PC pool size. The results are shown in the table.Also, the ratio of [3H]PC to [32P]PC in the AW did not change with time. We concluded that 1) IT and IV labeling gave comparable results. 2) IT NS and the added DPC behaved metabolically like endogenous NS. 3) That RU of PC in adult R (31%) is less than that of developing R (>90%).

Eighty-two 3-day-old rabbits were given by intratracheal injection doses of either radiolabeled natural sheep surfactant (NS) or sonicated suspensions of dipalmitoylphosphatidylcholine (DPPC) that contained >4x the endogenous phosphatidylcholine (PC) surfactant pool size. Recoveries of radiolabeled PC, total PC and PC specific activities (cpm/μmol PC) in alveolar washes (AW), lung tissue (L), and the total lung (AW+L) were measured over 72 hrs. More than half of the NS rapidly became L associated, and the labeled PC was linearly and slowly cleared from AW+L (0.28% of the initial injected cpm/hr). The alveolar surfactant pool size continued to increase despite the exogenously administered NS. Sonicated suspensions of DPPC were cleared from the AW+L at 0.71%/hr and only 15% of DPPC became L associated. The administration of large amounts of NS did not decrease the amount of intravenously injected radiolabeled choline, palmitic acid or 32P incorporated into lung PC or the amount of labeled PC secreted to the alveoli. Conclusions: 1) The % of injected PC associated with the L was higher and the rate of clearance from AW+L slower after a large dose of NS compared to an equivalent dose of DPPC. 2) Large doses of natural surfactant did not change endogenous synthetic and secretory rates. 3) Thus, the surfactant pool size apparently was not autoregulated by the animals following the administration of large doses of surfactant.