Getting high to cope with COVID-19: Modelling the associations between cannabis demand, coping motives, and cannabis use and problems.

During the COVID-19 pandemic, people may use substances like cannabis for enhancement or coping purposes. Behavioral economic demand for a substance is a key determinant of its use and misuse and can be measured via hypothetical purchase tasks. Previous research suggests that motivations to use a substance play a mediational role between elevated substance demand and problems, but comparable mechanistic research has yet to be done in the COVID-19 context and on the effects of cannabis demand on cannabis use patterns. Participants (n = 137) were recruited via the online crowdsourcing platform Prolific. Participants completed measures of cannabis use and problems, motivations for cannabis use, and the Marijuana Purchase Task. Two indices of demand, Persistence (i.e., sensitivity to increasing cost of cannabis) and Amplitude (i.e., consumption of cannabis at unrestricted cost), were related to increased cannabis problems via the use motive of coping during the COVID-19 pandemic. This model did not support the mediational role of enhancement motives. Those with increased cannabis demand who tend to use cannabis to cope are at increased risk of experiencing negative cannabis-related consequences during the COVID-19 pandemic.

Structure-activity relationships in C-terminal fragment analogs of pheromone biosynthesis activating neuropeptide in Helicoverpa zea.

A number of analogs of the C-terminal hexapeptide of PBAN were prepared and tested in vivo for pheromonotropic activity in Helicoverpa zea. Peptides prepared with longer-chain omega-aminocarboxylic acids (Tyr-6-aminocaproyl-Leu-NH2 and Tyr-7-aminoheptanoyl-NH2) were active at 25 and 2.5 nmol. Acetyl-Pro-Arg-Leu-NH2 was active at 1,000 pmol and represents a new minimum active fragment in the PBAN system. Addition of a bulky, hydrophobic tail (4-octylphenoxyacetyl) to the C-terminal hexapeptide of PBAN gave an analog that was active at all concentrations tested from 1 to 1,000 pmol when injected, had slight oral activity, but had no activity when applied topically. Glu-Tyr-Phe-Ser-Pro-Arg-Leu-NH2 was active at 1,000 but not at 100 pmol; at the latter dose it synergised the activity of 5 pmol of PBAN.

Cleavage of oligodeoxyribonucleotides from controlled-pore glass supports and their rapid deprotection by gaseous amines.

A novel method for the deprotection of oligodeoxyribonucleotides has been developed. Gaseous amines such as ammonia or methylamine were employed under pressure to achieve mild and rapid deprotection conditions. For example, oligodeoxyribonucleotides having a (tert-butyl)phenoxyacetyl group for the protection of the exocyclic amino function of cytosine, adenine and guanine were released from controlled-pore glass supports and fully deprotected by ammonia or methylamine under gas phase conditions, at room temperature, within 35 or 2 min respectively.

Synthetic pheromone biosynthesis activating neuropeptide gene expressed in a baculovirus expression system.

A synthetic gene of the pheromone biosynthesis activating neuropeptide (PBAN) of corn earworm Helicoverpa zea, with and without a signal sequence of the cuticle protein of Drosophila melanogaster, was cloned behind the polyhedrin promoter of AcMNPV. Two recombinant baculoviruses were constructed and used to infect a number of insect cell lines including Sf9 and 5B1-4. High pheromonotropic activity was consistently obtained from 5B1-4 cell culture that was infected with the recombinant baculovirus vINV-4 containing the signal sequence. The PBAN gene-product was isolated by HPLC and analyzed by electrospray ionization mass spectrometry. Low levels of biological activity obtained from Sf9 cells infected with the recombinant virus vPBAN may be due to lack of proper amidation at the C-terminus of the expressed peptide or rapid proteolytic degradation of the product.

Conformation of a biologically active C-terminal hexapeptide analog of the pheromone biosynthesis activating neuropeptide by NMR spectroscopy.

The solution conformation of a biologically active C-terminal hexapeptide analog of the pheromone biosynthesis activating neuropeptide Tyr-D-Phe-Ser-Pro-Arg-Leu-NH2 has been studied by NMR spectroscopy. A beta-turn conformation was identified from the NOE connectivities observed for the peptide in a mixed solvent of water and DMSO, indicating that this is the biologically active conformation of the peptide. This study also suggests that the use of such an aqueous-like solvent mixture allows the observation of a preferred conformation for small linear peptides in the presence of conformational averaging.

[Hydronephrosis in pregnancy]. / Die Harnstauung in der Schwangerschaft.

This is a report on the clinical course of a severe right-sided urinary retention in 21-year old patient, treated from the 24th week of pregnancy onwards. The special importance of the mechanical component involved in the genesis of this retention of urine is discussed on the occasion of the transitory spontaneous remission, observed, when the foetus turned to breech presentation.

Anti-immune complex antibodies enhance affinity and specificity of primary antibodies.

Antibodies have previously been described that enhance the binding of a second antibody to its antigen. The origin of this effect has been variously ascribed to binding to a neodeterminant on the Fc region, to a combined determinant representing portions of the second antibody and the immunogen, and to a ligand-induced conformation of the Fab fragment. This paper describes an antibody that recognizes an immune complex of an antibody to tetrahydrocannabinol (THC). The antibody binds the anti-THC antibody at an epitope recognized by an anti-idiotype antibody that is capable of blocking THC binding. The ability of various THC derivatives to enhance or inhibit binding taken together with equilibria and kinetic data support a model in which the anti-immune complex antibody interacts through adventitious binding to pendant groups on the THC derivatives. This type of interaction offers the opportunity to increase the sensitivity and specificity of immunoassays beyond the limits imposed by normal antibody binding. The implications of these findings with regard to earlier observations of anti-immune complex antibodies are discussed.

Molecular cloning of the pheromone biosynthesis-activating neuropeptide in Helicoverpa zea.

Pheromone biosynthesis-activating neuropeptide (PBAN) regulates sex pheromone biosynthesis in female Helicoverpa (Heliothis) zea. Two oligonucleotide probes representing two overlapping amino acid regions of PBAN were used to screen 2.5 x 10(5) recombinant plaques, and a positive recombinant clone was isolated. Sequence analysis of the isolated clone showed that the PBAN gene is interrupted after the codon encoding amino acid 14 by a 0.63-kilobase (kb) intron. Preceding the PBAN amino acid sequence is a 10-amino acid sequence containing a pentapeptide Phe-Thr-Pro-Arg-Leu, which is followed by a Gly-Arg-Arg processing site. Immediately after the PBAN amino acid sequence is a Gly-Arg processing site and a short stretch of 10 amino acids. This 10-amino acid sequence contains a repeat of the PBAN C-terminal pentapeptide Phe-Ser-Pro-Arg-Leu and is terminated by another Gly-Arg processing site. It is suggested that the PBAN gene in H. zea might carry, besides PBAN, a 7- and an 8-residue amidated peptide, which share with PBAN the core C-terminal pentapeptide Phe-(Ser or Thr)-Pro-Arg-Leu-NH2. The C-terminal pentapeptide sequence of PBAN represents the minimum sequence required for pheromonotropic activity in H. zea and also bears a high degree of homology to the pyrokinin family of insect peptides with myotropic activity. It is possible that the putative heptapeptide and octapeptide might be new members of the pyrokinin family, with pheromonotropic and/or myotropic activities. Thus, the PBAN gene products, besides affecting sexual behavior, might have broad influence on many biological processes in H. zea.

Isolation and identification of a new diuretic peptide from the tobacco hornworm, Manduca sexta.

A 30-amino acid diuretic peptide was isolated from the corpora cardiaca-corpora allata complexes and, separately, from medial neurosecretory cells of the Sphingid moth, Manduca sexta. The peptide was found to have the following sequence, determined by automated Edman degradation and mass spectrometry: SFSVNPAVDILQHRYMEKV AQNNRNFLNRV-NH2. We have named the peptide Mas-DP II. The peptide was synthesized and shown to possess diuretic activity in decapitated moths. Mas-DP II is related by sequence homology to a 41-amino acid diuretic peptide identified previously from M. sexta, and it belongs to the family of corticotropin releasing factor-like peptides.

Identification of a neuropeptide hormone that regulates sex pheromone production in female moths.

A pheromone biosynthesis activating neuropeptide (PBAN) hormone that controls sex pheromone production in female moths was identified from the brain-subesophageal ganglion complexes of the adult corn earworm, Heliothis zea. PBAN has 33 amino acid residues and a molecular weight of 3900. Its amino acid sequence has no significant homology with any of the fully characterized peptide hormones. The synthetic peptide, at a dose of between 2 and 4 picomoles, induced production of a normal quantity of sex pheromone in ligated H. zea females. The peptide also induced pheromone production in six other species of moths, thus indicating that this or similar peptides may be responsible for the regulation of pheromone production in moths.

A novel strategy for constructing clustered point mutations.

We have modified the synthetic linker mutagenesis procedure (1,2) in order to facilitate both the construction and the analysis of deletions, insertions and clustered point mutations generated in DNA in vitro. The protocol as originally described by McKnight and Kingsbury (1) involved attaching a synthetic linker sequence to each 5' or 3' deletion endpoint in DNA. We have designed specific plasmid vectors that can be used to generate nested sets of deletion mutations in the DNA being analyzed. The utility of these vectors is that a linker sequence of choice can be inserted at the endpoint of a deletion in a single intramolecular ligation without the use of synthetic linker DNA. In a second modification of the original procedure, we have adopted a rapid method for sequencing supercoiled plasmid DNAs from 10 ml cultures by primer extension. The site-directed mutagenesis strategy outlined here is suited for studying regulatory regions of DNA, such as origins of DNA replication, transcriptional promoters, enhancer elements, and activator binding sites. We have used this rapid and efficient strategy to generate deletions, insertions, and clustered point mutations in the transcriptional control region of a gene encoding the major human ribosomal RNAs.

Chemical and enzymatic biotin-labeling of oligodeoxyribonucleotides.

Biotin has been converted to 2-(biotinylamido)ethanol and condensed to phosphorylated oligonucleotides in a solid phase synthesis. The 5'-biotinylated oligonucleotides were enzymatically coupled to other DNA fragments by T4 DNA ligase or T4 RNA ligase. The hybridization properties of such biotin-labeled oligonucleotide probes were studied.

Multiple-copy genes: production and modification of monomeric peptides from large multimeric fusion proteins.

A vector system has been designed for obtaining high yields of polypeptides synthesized in Escherichia coli. Multiple copies of a synthetic gene encoding the neuropeptide substance P (SP) (Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2) have been linked and fused to the lacZ gene. Each copy of the SP gene was flanked by codons for methionine to create sites for cleavage by cyanogen bromide (CNBr). The isolated multimeric SP fusion protein was converted to monomers of SP analog, each containing a carboxyl-terminal homoserine lactone (Hse-lactone) residue (Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Hse-lactone), upon treatment with CNBr in formic acid. The Hse-lactone moiety was subjected to chemical modifications to produce an SP Hse amide. This method permits synthesis of peptide amide analogs and other peptide derivatives by combining recombinant DNA techniques and chemical methods.

Construction of improved M13 vectors using oligodeoxynucleotide-directed mutagenesis.

The restriction endonuclease cleavage sites for SphI and KpnI have been added to the lac cloning region of the phage vectors M13mp10 and M13mp11, using oligodeoxynucleotide-directed in vitro mutagenesis. Complementary deoxy 16-, 21- or 18-mers with the desired base changes were annealed to the M13mp DNA strand and extended with the Klenow fragment of DNA polymerase I. In adding these sites we have shown that this technique can be used as a general method for inserting sequences of DNA as well as introducing deletions and base pair changes.

Selective 2'-benzoylation at the cis 2',3'-diols of protected ribonucleosides. New solid phase synthesis of RNA and DNA-RNA mixtures.

5'-0-(Dimethoxytrityl)-2'-0-(benzoyl or 3,4,5-trimethoxybenzoyl)-base protected ribonucleosides have been prepared by selective benzoylation of the 2'-hydroxyl group. The isomerization of the 2'-benzoates to the 3'-benzoates was studied. The protected ribonucleosides have been converted to either methylphosphochloridites or methylphosphoamidites and used to synthesize oligoribonucleotides on silica gel solid support. The synthetic RNA were deprotected and isolated using conditions that minimize internucleotide cleavage. The use of 2'-benzoates as protecting groups for ribonucleosides has made it possible to easily prepare and isolate mixtures of DNA and RNA.

Synthesis of oligodeoxyribonucleotides on silica gel support.

A rapid solid phase method of oligonucleotide synthesis based on monomeric protected nucleosides has been developed.

Structural characteristics of interferons from mouse Ehrlich ascites tumor cells.

An improved procedure for the isolation of interferons produced by mouse Ehrlich ascites tumor cells infected with Newcastle disease virus provides interferons of three size classes (33,000, 26,000, and 20,000 daltons) with specific activities between 2 and 3 x 10(9) units/mg of protein and a yield of 11 to 20%. The tryptic peptide maps of the two larger species are very similar; that of the smallest species is different, at least in part. The amino acid compositions of the three species are very close. Their NH2-terminal amino acids are identical and so are the amino acids released by carboxypeptidase A treatment. These data are consistent with the possibility that the differences in size between the three species may be due, at least in part, to unequal glycosylation.

Stable mutants of mammalian cells that overproduce the first three enzymes of pyrimidine nucleotide biosynthesis.

Upon exposure to 0.1 mM N-phosphonacetyl-L-aspartate (PALA), a transition state analog inhibitor of aspartate transcarbamylase, most cells of a simian virus 40 (SV40)-transformed Syrian hamster line are killed within a few days, but resistant mutants form spontaneously with frequency 2-5 X 10(-5) in a stochastic process not dependent upon the presence of the inhibitor. The resistant phenotype is stable for many months in the absence of PALA. Other cell lines also give resistant mutants, but with substantially lower frequencies. Serial selection with PALA at concentrations up to 25 mM has yielded clones with more than 100 times the original aspartate transcarbamylase activity. The activities of carbamyl-P synthetase and dihydroorotase, which co-purify with aspartate transcarbamylase as a three-enzyme complex, increase in parallel with aspartate transcarbamylase activity in each resistant clone tested, but there is no substantial change in the activities of the last three enzymes of the de novo pathway, which are not in this complex. In each of the three resistant clones tested, there is an increase in the number of aspartate transcarbamylase active sites, determined by titration with 3H-PALA, which closely parallels the increase in enzyme activity. In one resistant clone tested, there is no change in the Ki for PALA or the Km for carbamyl-P. The only mechanism detected for achieving resistance to PALA is an increase in the steady state amount of the three enzyme complex.

Pyridoxal 5'-phosphate, a fluorescent probe in the active site of aspartate transcarbamylase.

Pyridoxal-P reacts specifically with a single lysine residue at the active site of Escherichia coli aspartate transcarbamylase (Greenwell, P., Jewett, S. L., and Stark, G. R. (1973) J. Biol. Chem. 248, 5994-6001). Reduction of the Schiff base with sodium borohydride, succinylation of the remaining lysine residues, and digestion with trypsin result in formation of a single pyridoxyl peptide, which was purified to homogeneity after chromatography on DEAE-cellulose, treatment with alkaline phosphatase, and rechromatography. Amino acid composition and the results of limited sequential degradation showed that this peptide corresponds to residues 62 to 98 in the sequence of Konigsberg and co-workers, and contains 2 residues of lysine (Henderson, L., Roy, D., Martin, D., and Konigsberg, W., personal communication). By similar isolation, a second peptide was obtained from unsuccinylated catalytic subunit, containing only the pyridoxylated lysine, which corresponds to Lys-80. Derivatives of catalytic subunit containing an average of either one, two, or three pyridoxamine-P moieties per trimer have been prepared by reduction. These species, which retain catalytic activity in proportion to their unmodified active sites, were recombined with regulatory subunit to prepare partially modified derivatives of native aspartate transcarbamylase. At pH 8, fluorescence emission bands were observed at 340 nm, due to aromatic amino acids in the protein, and at 395 nm, due to the pyridoxamine-P moiety. Upon excitation at 280 nm energy transfer from protein to pyridoxamine-P was approximately 15%. The properties of the probe were used to study changes accompanying the binding of substrates and inhibitors. The effects of CTP and ATP were small. With the transition state analog N-(phosphonacetyl)-L-aspartate (PALA) or the substrate carbamyl-P, two types of response were observed. Derivatives of catalytic subunit and native enzyme which contain some unmodified sites and hence retain partial catalytic activity gave large increases in fluorescence at 395 nm. However, fully modified inactive derivatives gave much smaller increases. A derivative of native enzyme containing one triply modified and one unmodified catalytic subunit behaved like the other partially modified species. These results indicate that there is communication among the active sites of different catalytic trimers in modified native enzyme, as well as among active sites within the same modified catalytic trimer. The increases in fluorescence result from a red shift of the absorption maximum of the pyridoxamine-P moiety from 315 to 325 nm, which increases the absorbance at the excitation wavelength for fluorescence. At pH 7, the absorption spectrum is already shifted and, consequently, the binding of PALA and carbamyl-P has little effect on the fluorescence. Therefore, the binding of these compounds at pH 8.0 must cause a structural change in the protein, which in turn causes protonation of a group in the modified active sites, altering the spectral properties.