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J Moss

Publications and source records attributed to J Moss.

At least 415 records · Page 23Linked to original sources
PubMed1986

Identification of the probable site of choleragen-catalyzed ADP-ribosylation in a Go alpha-like protein based on cDNA sequence.

Go alpha, a 39-kDa guanyl nucleotide-binding protein, is functionally and structurally similar to the alpha subunits of the stimulatory and inhibitory guanyl nucleotide-binding proteins (Gs alpha, Gi alpha) of adenylate cyclase and to the alpha subunit of transducin (T alpha), the guanyl nucleotide-binding protein of the retinal photon reception system. A cDNA clone was isolated from a bovine retinal lambda gt10 library by using oligonucleotide probes complementary to sequences in two putative T alpha clones. Partial sequence analysis revealed a deduced amino acid sequence identical to sequences of four tryptic peptides from bovine brain Go alpha. Gs alpha and T alpha are known to serve as substrates for ADP-ribosylation by choleragen. Other workers have established the sequence of the tetrapeptide in T alpha containing the arginine that is ADP-ribosylated and its location in the amino acid sequence deduced from T alpha cDNA. The Go alpha cDNA described here includes a region encoding an amino acid sequence very similar to that surrounding the ADP-ribosylation site in T alpha, consistent with observations that Go alpha can also be a substrate for choleragen. A corresponding sequence in the recently identified Gs alpha cDNA is less homologous to that in T alpha or Go alpha. The reported differences in conditions that promote choleragen-catalyzed ADP-ribosylation of Gs alpha vs. Go alpha could be related to differences in amino acid sequence in the region of the acceptor arginine.

Adenosine Diphosphate Ribose↗
PubMed1986

Fibrillar organization of fibronectin is expressed coordinately with cell surface gangliosides in a variant murine fibroblast.

NCTC 2071A cells, a line of transformed murine fibroblasts, grow in serum-free medium, are deficient in gangliosides, synthesize fibronectin, but do not retain and organize it on the cell surface. When the cells are exposed to exogenous gangliosides, fibrillar strands of fibronectin become attached to the cell surface. A morphologically distinct variant of NCTC 2071A cells was observed to both retain cell surface fibronectin and organize it into a fibrillar network when the cells were stained with anti-fibronectin antibodies and a fluorescent second antibody. A revertant cell type appeared to resemble the parental NCTC 2071A cells in terms of morphology and fibronectin organization. All three cell types were subjected to mild NaIO4 oxidation and reduction with KB3H4 of very high specific radioactivity in order to label the sialic acid residues of surface gangliosides. The variant had much more surface gangliosides than the parental, particularly more complex gangliosides corresponding to GM1 and GD1a. The surface gangliosides of the revertant were intermediate between the parental and the variant. By using sialidase, which hydrolyzes GD1a to GM1, and 125I-labeled cholera toxin, which binds specifically to GM1, the identity and levels of these gangliosides were confirmed in the three cell types. When variant cells were exposed to sialidase for 2 d, there appeared to be little change in fibronectin organization. Concomitant treatment of the cells with the B subunit of cholera toxin, which bound to all the surface GM1 including that generated by the sialidase, however, eliminated the fibrillar network of fibronectin. In addition, exposure of the variant cells to a 70,000-mol-wt fragment of fibronectin, which lacks the cell attachment domain but contains a matrix assembly domain, inhibited the formation of fibers. Finally, all three cell types were assayed for their ability to attach to and spread on fibronectin-coated surfaces; no significant differences were found. Our results further establish that the ability of a cell to organize fibronectin into an extracellular matrix is dependent on certain gangliosides, but they also indicate that cell adhesion to fibronectin is independent of these gangliosides. We suggest that matrix organization and cell attachment and spreading are based on separate mechanisms and that these functions are associated with different cell surface "receptors."

Animals↗
PubMed1986

Human interferons active on murine cells induce pulmonary cysts in A2G mice.

Suckling A2G mice were injected daily from birth for 8 days with highly purified human lymphoblastoid interferon (IFN) or recombinant interferons-alpha 1 or -alpha 2 rIFN-alpha 1, rIFN-alpha 2), or mouse interferon-alpha/beta (IFN-alpha/beta), or control preparations. Only mouse IFN inhibited the growth of suckling A2G mice and induced liver cell necrosis. At 56 days the mice were killed and the lungs examined for the presence of pulmonary cysts. Human lymphoblastoid IFN and rIFN-alpha 1 (and mouse IFN-alpha/beta), which exhibited significant biological activity on mouse cells in culture, induced pulmonary cysts in A2G mice. rIFN-alpha 2, which showed little or no activity on mouse cells, did not induce pulmonary cysts.

Animals↗
PubMed1986

Histamine release during the administration of atracurium or vecuronium in children.

The histamine releasing potential of equivalent bolus doses of atracurium 0.6 mg kg-1 or vecuronium 0.12 mg kg-1 was evaluated in 20 children anaesthetized with halothane. Blood samples were obtained before, and at 2 and 5 min after the administration of the neuromuscular blocker. The twitch response to 0.15 Hz was also evaluated. None of the 10 patients receiving vecuronium had a significant increase in plasma histamine concentration. In two of the 10 children receiving atracurium, the plasma histamine concentration increased markedly, but without any apparent clinical manifestations. Recovery of neuromuscular function (to 95% twitch height) after vecuronium 0.12 mg kg-1 was faster than after atracurium 0.6 mg kg-1 (P less than 0.02).

Atracurium↗
PubMed1986

Antibody to mouse alpha/beta interferon abrogates Pichinde virus-induced liver lesions in suckling mice.

Infection of newborn C3HeB/FeJ mice with the arenavirus Pichinde resulted in stunted growth, severe liver cell degeneration, and death. Administration of sheep anti-mouse alpha/beta interferon globulin completely abrogated liver lesions in virus-infected mice, although it did not decrease the incidence of mortality. These results indicate that endogenous interferon may be responsible for some manifestations of viral disease.

Animals↗
PubMed1986

Arthrosonography of the irritable hip in childhood: a review of 1 year's experience.

A retrospective study of 87 children presenting acutely with an "irritable hip" was undertaken to assess the role of arthrosonography of the hip joint. Arthrosonography detected 52 hip-joint effusions, of which 16 were aspirated and an effusion confirmed in 14 (88%). In 82 cases plain radiography was compared with arthrosonography for the detection of hip-joint effusions. Of 47 children with a positive ultrasound diagnosis, 28 (59%) showed abnormal findings on plain radiographs and, of 35 cases with negative ultrasound findings, 22 (63%) had a negative diagnosis by plain radiography. Patients with more severe clinical signs were more likely to have an ultrasonic diagnosis of an effusion (87%-100%) than those with mild clinical signs (25%). The ultrasonic measurement of the hip-joint capsule to femoral neck distance was 2.2 mm +/- 0.5 mm (mean +/- 1 SD) in normal hips and 6.3 mm +/- 1.5 mm in the joints with effusions. Our study suggests that arthrosonographically the normal capsular space is less than 3 mm and the difference between the two sides less than 2 mm. It is suggested that hip arthrosonography is a more accurate method for detecting hip-joint effusions than plain radiography; it may help select cases for hospital admission and should be performed before aspiration is attempted.

Adolescent↗
PubMed1986

Structural and functional characterization of guanyl nucleotide-binding proteins using monoclonal antibodies to the alpha-subunit of transducin.

Transducin, the GTP-binding protein of the retinal light-sensitive phosphodiesterase system, and Gs and Gi, regulatory proteins of the hormone-sensitive adenylate cyclase, are members of a family of guanyl nucleotide-binding proteins termed G proteins that are important in signal transduction. To probe relationships within this family of G proteins, monoclonal antibodies were prepared against the alpha-subunit of bovine transducin (T alpha). Three of four monoclonal antibodies were specific for T alpha and did not cross-react with other G proteins. One, MAB1, cross-reacted strongly with the alpha-subunit of Gi (Gi alpha) purified from rabbit liver and, to a lesser extent, with the alpha-subunit of Go (Go alpha) purified from bovine brain and the proto-oncogene product H-ras p21. All four monoclonal antibodies recognized epitopes on a 23-kDa tryptic peptide fragment of T alpha which is derived from the N-proximal region. The three monoclonal antibodies that recognized only T alpha inhibited rhodopsin-stimulated GTP binding and hydrolysis by transducin, whereas MAB1 had no significant effect in these assays. These studies demonstrate that, within the 23-kDa tryptic peptide of T alpha, there is a domain(s) unique to T alpha that is involved in GTP binding and hydrolysis and another domain which is highly conserved in T alpha and to a lesser extent in other G proteins. Prior studies have identified regions involved in nucleotide binding and hydrolysis that are homologous in all G proteins. The observations reported here are consistent with the conclusion that the G proteins may have in addition unique regions involved in these functions.

Amino Acid Sequence↗
PubMed1986

Effects of nitroprusside on the bradykinin responsiveness of human fibroblasts.

The effects of agents that cause vasodilatation and hypotension, such as endogenously produced bradykinin (BK) or the drug nitroprusside (NP), appear to result from effects on cyclic nucleotides (cGMP, cAMP) and arachidonate metabolism. Cultured human fibroblasts, which possess B2 BK receptors and respond to NP with an increase in cGMP, were used to study the interaction of these agents at the molecular level. Addition of BK or NP to cultured human fibroblasts caused a rapid increase in cGMP. The effect of NP was usually maximal within 30 sec, after which cGMP content declined. The increase in cGMP produced by BK reached a maximum at approximately 1 min and then fell; the rise with NP was more than 10 times that with BK. At 30 sec, cGMP content with NP plus BK was less than with NP alone. At later times, however, effects of BK and NP were slightly more than additive and maximal cGMP levels were reached at 90 sec. BK increased prostaglandin production by the fibroblasts; it is believed that the kinin-induced elevation in cAMP content is secondary to increased prostaglandin formation. NP caused a small, early increase in cAMP without significant effect on prostaglandin I2 (PGI2); after 2.5 min, effects on PGI2 and cAMP were greater with BK and NP than with BK alone. To study further the roles of arachidonate metabolites in the fibroblast response to BK and NP, the cyclooxygenase inhibitor, indomethacin, and the combined lipoxygenase and cyclooxygenase inhibitor, 5,8,11,14-eicosatetraynoic acid (ETYA), were added to fibroblasts prior to BK or NP. Increases in cAMP or PGI2 with BK or BK plus NP were blocked by indomethacin or ETYA. These effects of BK or BK plus NP on cAMP thus appear to be mediated through cyclooxygenase products of arachidonate metabolism. Indomethacin and ETYA did not affect cGMP in the presence of BK plus NP but enhanced NP-stimulated cGMP accumulation by 40-50%; effects of NP on cGMP may be independent of or perhaps inhibited by cyclooxygenase derivatives. Cellular responses to BK plus NP differed quantitatively and temporally from the sum of effects of BK and NP alone. Through interactions of this type, in vivo responses to drugs like NP may be influenced by levels of BK or similar endogenous mediators.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed1986

The effect of diazepam on induction of anesthesia with alfentanil.

This study investigated the effect of intravenous diazepam on induction of anesthesia with alfentanil. Forty ASA physical status I and II patients were given one of four treatments: alfentanil 100 micrograms/kg or 200 micrograms/kg, without diazepam or preceded by 0.125 mg/kg diazepam intravenously. Blood pressure, heart rate, respiration, response to verbal command, and movement were assessed for 5 min, and blood was taken for measurement of histamine, epinephrine, and norepinephrine. All ten patients receiving 100 micrograms/kg and five of the ten patients receiving 200 micrograms/kg of alfentanil responded to voice after 5 min, but only one in each group responded when it was preceded by diazepam. There was no rigidity or serious arrhythmias in any patient. Heart rate increased in patients receiving alfentanil alone. Blood pressure increased in those receiving 100 micrograms/kg but not 200 micrograms/kg. In patients given diazepam, tachycardia did not occur, but blood pressure decreased after administration of alfentanil. There were no significant changes in plasma levels of histamine or catecholamines. Five of the six cases of inadequate postoperative ventilation were in patients given diazepam. Despite these effects, diazepam or some other hypnotic agent may be indicated when alfentanil is used for induction.

Adult↗
PubMed1986

Accidental severe hypothermia.

Accidental hypothermia is a health problem with a scope which has been underestimated by the medical community. Limited awareness and limited diagnostic equipment, along with hospital coding inaccuracies, make calculation of the true number of instances of accidental hypothermia nearly impossible. Severe hypothermia occurs when body temperature falls below 28 degrees C. The patient may be unconscious, with such severely depressed vital signs that he appears to be dead. All such patients, regardless of extremis upon presentation, should undergo vigorous cardiopulmonary resuscitation in addition to rewarming, because a reliable determination of death is nearly impossible without the restoration of body temperature. Rewarming must follow the implementation of adequate cardiovascular support, maintaining serum acid base balance, arterial oxygenation and intravascular volume levels within the appropriate physiologic ranges; otherwise, the reawakening of metabolic needs will outpace the recovery of cardiac function, and the patient will die of multiple organ infarction. In addition, standard mechanical or manual CPR can furnish adequate cardiovascular support for the severely failing myocardium. When cardiovascular resuscitation is performed first, followed by rewarming with a continual maintenance of optimum cardiovascular function, then all standard methods of rewarming (external rewarming with a fluid-circulated blanket, peritoneal lavage or partial cardiac bypass) should give equally good results. The preceding guidelines are extrapolated from a retrospective review of available clinical material as well as controlled prospective animal studies. Prospective clinical studies should be performed to confirm the acceptability of these guidelines; an inter-institutional study may be the best way to glean such data and should be considered by researchers interested in this problem.

Accidents↗
PubMed1985

Amino acid-specific ADP-ribosylation. Sensitivity to hydroxylamine of [cysteine(ADP-ribose)]protein and [arginine(ADP-ribose)]protein linkages.

Hydroxylamine stability has been used to classify (ADP-ribose)protein bonds into sensitive and resistant linkages, with the former representing (ADP-ribose)glutamate, and the latter, (ADP-ribose)arginine. Recently, it was shown that cysteine also serves as an ADP-ribose acceptor. The hydroxylamine stability of [cysteine([32P]ADP-ribose)]protein and [arginine([32P] ADP-ribose)]protein bonds was compared. In transducin, pertussis toxin catalyzes the ADP-ribosylation of a cysteine residue, whereas choleragen (cholera toxin) modifies an arginine moiety. The (ADP-ribose)cysteine bond formed by pertussis toxin was more stable to hydroxylamine than was the (ADP-ribose)arginine bond formed by choleragen. The (ADP-ribose)cysteine bond apparently represents a third class of ADP-ribose bonds. Pertussis toxin ADP-ribosylates the inhibitory guanyl nucleotide-binding regulatory protein (Gi) of adenylate cyclase, whereas choleragen modifies the stimulatory guanyl nucleotide-binding regulatory protein (Gs). These (ADP-ribose)protein linkages are identical in stability to those formed in transducin by the two toxins, consistent with the probability that cysteine and arginine are modified in Gi and Gs, respectively. Bonds exhibiting differences in hydroxylamine-stability were found in membranes from various non-intoxicated mammalian cells following incubation with [32P]NAD, which may reflect the presence of endogenous NAD:protein-ADP-ribosyl-transferases.

Adenosine Diphosphate Ribose↗
PubMed1985

Modification of proteins by mono(ADP-ribosylation) in vivo.

We have pursued the detection of in vivo modified, ADP-ribosylated proteins containing N-glycosylic linkages to arginine. ADP-ribosylated histone, elongation factor 2, and transducin, containing the different known ADP-ribosylated amino acids (arginine, diphthamide, and cysteine, respectively), were employed as model conjugates to establish conditions for the selective detection of adenosine(5')diphosphoribose (ADP-ribose) residues bound to arginine. We report here the detection and quantification of protein-bound ADP-ribose residues in adult rat liver with linkages characteristic of arginine. These mono(ADP-ribose) residues were present in vivo at a level of 31.8 pmol/mg of protein which is 400-fold higher than polymeric ADP-ribose residues. A minor fraction (23%) of the ADP-ribose residues detected were bound via a second, more labile linkage with chemical properties very similar to those described for carboxylate ester linked ADP-ribose.

Adenosine Diphosphate Ribose↗
PubMed1985

Pertussis toxin-catalyzed ADP-ribosylation of transducin. Cysteine 347 is the ADP-ribose acceptor site.

Pertussis toxin catalyzes the transfer of ADP-ribose from NAD to the guanine nucleotide-binding regulatory proteins Gi, Go, and transducin. Based on a partial amino acid sequence for a tryptic peptide of ADP-ribosylated transducin, asparagine had been characterized as the site of pertussis toxin-catalyzed ADP-ribosylation. Subsequently, cDNA data for the alpha subunit of transducin indicated that the putative asparagine residue was, in fact, not present in the protein. To determine the amino acid that served as the ADP-ribose acceptor, radiolabel from [adenine-U-14C]NAD was incorporated, in the presence of pertussis toxin, into the alpha subunit of transducin (0.3 mol/mol). An ADP-ribosylated, tryptic peptide was purified and fully sequenced by automated Edman degradation. The amino acid sequence, Glu-Asn 343-Leu-Lys-Asp 346-X-Gly 348-Leu-Phe, corresponds to the cDNA sequence coding the carboxyl-terminal nonapeptide, Glu 342-Phe 350, which includes by cDNA sequence cysteine at position 347. Neither Asn 343 nor Asp 346 appeared to be modified; residue 347 adhered to the sequencing resin. Cysteine, the missing residue, was eluted from the sequencing resin with acetic acid along with 76% of the peptide-associated radioactivity, half of which, presumably ADP-ribosylcysteine, eluted from an anion exchange column between NAD and ADP-ribose; the other half had a retention time corresponding to 5'-AMP. We conclude that Cys 347 and not Asn 343 or Asp 346 is the site of pertusis toxin-catalyzed ADP-ribosylation in transducin.

Adenosine Diphosphate Ribose↗
PubMed1985

ADP-ribosylation of transducin by pertussis toxin.

Transducin, the guanyl nucleotide-binding regulatory protein of retinal rod outer segments that couples the photon receptor, rhodopsin, with the light-activated cGMP phosphodiesterase, can be resolved into two functional components, T alpha and T beta gamma. T alpha (39 kDa), which is [32P]ADP-ribosylated by pertussis toxin and [32P]NAD in rod outer segments and in purified transducin, was also labeled by the toxin after separation from T beta gamma (36 kDa and approximately 10 kDa); neither component of T beta gamma was a pertussis toxin substrate. Labeling of T alpha was enhanced by T beta gamma and was maximal at approximately 1:1 molar ratio of T alpha : T beta gamma. Limited proteolysis by trypsin of T alpha in the presence of guanyl-5'-yl imidodiphosphate (Gpp(NH)p) resulted in the sequential appearance of proteins of 38 and 32 kDa. The amino terminus of both 38- and 32-kDa proteins was leucine, whereas that of T alpha could not be identified and was assumed to be blocked. The 32-kDa peptide was not a pertussis toxin substrate. Labeling of the 38-kDa protein was poor and was not enhanced by T beta gamma. Trypsin treatment of [32P]ADP-ribosyl-T alpha produced a labeled 37-38-kDa doublet followed by appearance of radioactivity at the dye front. It appears, therefore, that, although the 38-kDa protein was poor toxin substrate, it contained the ADP-ribosylation site. Without rhodopsin, labeling of T alpha (in the presence of T beta gamma) was unaffected by Gpp(NH)p, guanosine 5'-O-(thiotriphosphate) (GTP gamma S), GTP, GDP, and guanosine 5'-O-(thiodiphosphate) (GDP beta S) but was increased by ATP. When photolyzed rhodopsin and T beta gamma were present, Gpp(NH)p and GTP gamma S decreased [32P]ADP-ribosylation by pertussis toxin. Thus, pertussis toxin-catalyzed [32P]ADP-ribosylation of T alpha was affected by nucleotides, rhodopsin and light in addition to T beta gamma. The amino terminus of T alpha, while it does not contain the pertussis toxin ADP-ribosylation site, appeared critical to its reactivity.

Adenosine Diphosphate Ribose↗