Molecular cloning and complete nucleotide sequence of galinsoga mosaic virus genomic RNA

Summary.  The complete genomic sequence of galinsoga mosaic virus (GaMV) was determined. The genome consists of 3 803 nucleotides and has five open reading frames (ORFs). The 5′ ORF (ORF 1) encodes a protein with predicted molecular mass of 23 kDa and readthrough of its amber stop codon probably yields a 82 kDa protein (ORF 2). ORFs 3 and 4 encode two polypeptides with molecular masses of 8 and 7 kDa, respectively. ORF 5 encodes the 36 kDa capsid protein. Amino acid sequence comparisons revealed that the nonstructural proteins encoded by ORFs 1, 3, and 4 were more similar to the corresponding gene products of tobacco necrosis virus, strain A, than to those of carmoviruses. Conversely, the coat protein was more similar to that of tombusviruses. The readthrough region of the viral replicase (ORF 2) had high sequence homology with that of carmo-, tombus-, and necroviruses. Computer analysis of the protein encoded by ORF 1 as well as of the corresponding product of turnip crinkle (TCV) and melon necrotic spot (MNSV) carmoviruses revealed the presence of a sequence with local hydrophobicity and hydrophobic moment characteristic of mitochondrial targeting sequence which may explain the origin of the carmovirus-induced multivesicular bodies from mitochondria. Accepted August 25, 1997 Received June 18, 1997     

FEASIBILITY OF CONDUCTING CARDIOVASCULAR OUTCOME RESEARCH IN AUSTRALIAN GENERAL PRACTICE: RESULTS FROM THE ANBP2 PILOT STUDY

1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.     

SUICIDE ATTEMPT DUE TO METOCLOPRAMIDE-INDUCED AKATHISIA

Akathisia as a side-effect of metoclopramide has received increasing attention in consultation-liaison psychiatry in recent years. A case of metoclopramide-induced akathisia resulting in a suicide attempt is reported in order to highlight the suffering of such patients and the factors that lead to misdiagnosis.     

Experimental axonopathy induced by immunization with campylobacter jejuni lipopolysaccharide from a patient with guillain‐barré syndrome

Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection.     

Contribution of P1-(A2b subtype) and P2-purinoceptors to the control of vascular tone in the rat isolated mesenteric arterial bed.

1. The direct vascular effects of adenosine and ATP were compared in the isolated and perfused mesenteric arterial bed of the rat. The actions of analogues of adenosine and ATP were also examined. 2. In preparations at basal tone, adenosine lacked vasoconstrictor actions, while ATP elicited dose-dependent vasoconstrictor responses. When the tone of preparations was raised by adding methoxamine to the perfusate, adenosine and its stable analogue, 2-chloroadenosine (2-CADO) elicited dose-dependent vasodilation. The A2 adenosine receptor agonist, 5'-N-ethylcarboxamidoadenosine (NECA) was active at lower doses than adenosine, while the A2a-selective agonist, CGS 21680 and the selective A1 agonist, N6-cyclopentyladenosine (CPA) failed to induce vasodilatation. ATP and its analogue, 2-methylthio ATP, elicited dose-dependent vasodilatation at doses 400 fold lower than adenosine. 3. Vasodilator responses to adenosine and 2-CADO were sensitive to antagonism by 1 microM 8-sulphophenyltheophylline (8-SPT) and were unaffected by inhibition of nitric oxide synthase by N omega-nitro-L-arginine methyl ester (L-NAME). In contrast, vasodilator responses to ATP were not sensitive to antagonism by 8-SPT and were almost abolished by L-NAME treatment. 4. These results indicate that in the rat mesenteric arterial bed, while both adenosine and ATP participate in the purinergic control of vascular tone, adenosine appears to be a weaker vasodilator than ATP and lacks vasoconstrictor action. A2b adenosine receptors account for the adenosine-induced vasodilatation which is independent of the production of nitric oxide.     

Evaluation of 3 different methods for determining triiodothyronine (T-3) and thyroxine (T-4)

The authors compare three methodologies based on the immunology (RIA, FPIA, LIA) in the determination of two important parameters of the so-called thyroid outline: triiodothyronine (T-3) and thyroxine (T-4). The correlations between the analytic systems examined are presented and discussed.