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J Aldrich

Publications and source records attributed to J Aldrich.

At least 19 recordsLinked to original sources
PubMed1998

Cloning and characterization of Physarum polycephalum tectonins. Homologues of Limulus lectin L-6.

Previous investigators have reported the presence of two dominant proteins, tectonin I (25 kDa) and tectonin II (39 kDa), in nuclei and nuclear matrix from plasmodia of Physarum polycephalum. We demonstrate, by a modification of the nuclear isolation protocol and by protease sensitivity, that the tectonins are not nuclear proteins but rather are located on the exterior surface of the plasma membrane. We report the sequences of cDNAs of tectonins I and II, which encode 217 and 353 amino acids, respectively. Tectonin I is homologous to the C-terminal two-thirds of tectonin II. Both proteins contain six tandem repeats that are each 33-37 amino acids in length and define a new consensus sequence. Homologous repeats are found in L-6, a bacterial lipopolysaccharide-binding lectin from horseshoe crab hemocytes. The repetitive sequences of the tectonins and L-6 are reminiscent of the WD repeats of the beta-subunit of G proteins, suggesting that they form beta-propeller domains. Tectonin II has an additional N-terminal domain that includes a 47-residue sequence highly similar to the galactoside-binding sequence of the B-chain of ricin. The tectonins may be lectins that function as part of a transmembrane signaling complex during phagocytosis.

Amino Acid Sequence↗
PubMed1997

Radiological sciences, past and present.

Few observations can have been as rapidly and widely disseminated in medicine as the diagnostic X-ray (radiograph). The first few decades after Röntgen's discovery saw technical developments that made radiography more practical, quicker, safer for both imager and patient, and able to achieve greater contrast. This article reviews the history of imaging but it also looks to the future and begins to open up some of the issues that radiology faces in the 21st century--issues that the next six articles in this Lancet series will enlarge upon. The conventional radiograph remains the most common medical image but a host of new techniques have come along. Are they research tools, clinical methods, or both--and how, in an age of sensitivity about the costs of health care, do they stand up?

History, 19th Century↗
PubMed1994

Pulmonary edema.

Explore the source record for details and available documents.

Adult↗
PubMed1992

The flax ribosomal RNA-encoding genes are arranged in tandem at a single locus interspersed by 'non-rDNA' sequences.

The ribosomal RNA (rRNA)-encoding genes (rDNA) in flax, estimated to be present in about 2400 copies per diploid nucleus, have been reported as a single homogeneous repeat unit of 8.6 kb. In situ hybridization analysis indicated that these genes were located at a single site on one pair of chromosomes. However, an analysis of a flax variety, CI 1303, has revealed heterogeneity in the intergenic spacer of the rDNA repeat unit. A genetic analysis of rDNA inheritance in two flax lines, Stormont Cirrus and CI 1303, has again supported the observation that there is a single rDNA locus in this plant species. Screening of four different genomic libraries made in methylation-sensitive and -insensitive systems, and the analysis of 40 phage clones, demonstrate a much higher number than that expected of junctions between rDNA and non-rDNA. Direct evidence of rRNA-encoding genes being present in tandem comes from a few phage clones that contain more than two rDNA repeats. The evidence presented here indicates that rDNA, although present at a single locus in tandem arrays, may be interrupted frequently by other non-rDNA sequences, thus giving rise to questions about their organization into long tandem arrays.

Blotting, Southern↗
PubMed1992

Cardioplegic arrest of the myocardium with calcium blocking agents.

This study was designed to compare the effects of the calcium slow channel blocking agents verapamil (0.15 mg/kg), diltiazem (0.15 mg/kg), and nifedipine (50 micrograms/kg) on the myocardium after global ischemia and reperfusion in the in situ canine model. Animals were subjected to 120-min normothermic global ischemia, followed by 45-min reperfusion. Cardioplegic arrest of the myocardium was achieved by administering one of the three calcium antagonists in a multidose fashion. Superior preservation (p less than 0.01) of left ventricular (LV) systolic function was achieved in group I (verapamil cardioplegia). dP/dt, at an intraventricular balloon volume of 25 cc, was 83% of control after reperfusion in group I. Group II (diltiazem) and group III (nifedipine) achieved only 55 and 63% of their preischemic dP/dt values. LV chamber stiffness was increased in hearts protected with nifedipine. The exponential constant m was increased from 0.04 +/- 0.01 to 0.08 +/- 0.01. Coronary blood flow after reperfusion increased from 120 to 184 cc/100 gr/min in group I (p less than 0.01). The hyperemic response in group III was negligible. The O2 consumption of the reperfused myocardium was not significantly altered in any of the treatment groups. Lactate metabolism during ischemia and after reperfusion was similar in all groups. ATP values were markedly reduced in all groups (p less than 0.05). Immediately after ischemia, ATP was 50, 28, and 44% of control in group I, II, and III, respectively. The excellent preservation of systolic function and a physiologic hyperemic response by verapamil could not be correlated with improved preservation of high-energy compounds or with significant changes in myocardial O2 consumption.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1992

A review of the oncology curriculum at Dalhousie medical school.

The teaching of oncology at Dalhousie medical school is currently left to the discretion of the 30 university departments. There is no central coordination. This organization leaves no monitoring of curriculum content to see that what should be covered is indeed covered, nor does it provide teaching from the perspective of oncology rather than the perspective of the other individual disciplines. Following an inventory of the oncology curriculum and a survey of interns graduating from Dalhousie in 1991, we recognize deficiencies in the clinical portion of the curriculum that could be rectified with a small number of hours designed to teach the various aspects of the management of cancer patients in case-scenario, student participation sessions.

Curriculum↗
PubMed1988

Sequence analysis of the junction of the large single copy region and the large inverted repeat in the petunia chloroplast genome.

We have determined the nucleotide sequence at the junction of the large single copy (LSC) region and the right and left members of the large inverted repeat, IRA and IRB, respectively, of the petunia chloroplast (cp) genome. As in Nicotiana debneyi and spinach (Zurawski et al. 1984), coding sequences of rps19 of petunia overlap the junction of IRB and LSC. Immediately into the LSC region upstream of IRA in the petunia cp genome are two small insertions relative to N. debneyi that occur at sites just inside IRA of N. debneyi. We discuss how these additions in one copy of the large inverted repeat of an N. debneyi-like ancestor to petunia resulted in shortening of the petunia large inverted repeat by 8 bases and in the resultant slight movement of rps19 farther into LSC. On a larger scale, the large inverted repeat in the tobacco, N. debneyi and petunia lineage relative to a spinach-like ancestor may have sustained several contractions due to deletions between short direct repeats found within IRA and the IRA/LSC junction. We also show how the large inverted repeat of N. debneyi instead may have been expanded relative to a tobacco-like ancestor by insertion into the large inverted repeat of bases between short inverted repeat sequences in LSC and the LSC/IRB junction.

Base Sequence↗
PubMed1988

The role of insertions/deletions in the evolution of the intergenic region between psbA and trnH in the chloroplast genome.

TrnH and the intergenic region between trnH and psbA of the chloroplast genomes of alfalfa (Medicago sativa), Fabaceae, and petunia (Petunia hybrida), Solanaceae, were sequenced and compared to published sequences of that region from other members of those families. A striking feature of these comparisons is the occurrence of insertions/deletions between short, nearly perfect AT-rich direct repeats. The directionality of these mutations in the petunia, tobacco and Nicotiana debneyi lineages within the Solanaceae cannot be discerned. However, we present several alternative hypotheses that are consistent with Goodspeed's 1954 evolutionary treatment of the genus Nicotiana and family Solanaceae. Within the Fabaceae, the major size differences in the intergenic region between alfalfa, pea and soybean are due to insertions/deletions between direct repeats. The alfalfa intergenic region has an inverted repeat stem-loop structure of 210 bases directly 5' to trnH. This structure is an insert relative to the liver-wort. Marchantia polymorpha. Portions of the insert are found also in pea and soybean as well as in published sequences from other dicots representing diverse orders: petunia, tobacco, N. debneyi (Scrophulariales), spinach (Caryophyllales), and Brassica napus (Capparales). Some of the regions of the insert that are missing in these plants appear to have resulted from deletions of sequences between different imperfect direct repeats within, or 5' to and within the insert. Other deletions are not flanked by repeated sequences. A short insert flanked by imperfect direct repeats in B. napus occurs just within the longer alfalfa insert suggesting that both alfalfa and B. napus have remnants of an even longer insert relative to M. polymorpha. From these analyses we hypothesize the insertion of a stem-loop structure into an M. polymorpha-like ancestral land plant, followed by deletions of sequences, often between different imperfect direct repeats within and upstream of the insert, leading to the psbA-trnH intergenic sequences represented by the present-day plants examined.

Base Sequence↗
PubMed1988

The Camberwell Collaborative Depression Study. II. Investigation of family members.

Out of a consecutive series of 130 potential probands with recent onsets of depression, 124 were deemed 'in scope' for a family interview study of social and genetic influences on depression. We were able to interview first-degree relatives of 83 probands (67% of those families 'in scope'). Unexpectedly, interviewed first-degree relatives had, on average, a significantly lower occupational status than the depressed probands. However, the rates of depression among the first-degree relatives were high. Based on a PSE-Catego classification, 17.2% of 244 relatives were current 'cases' of depression at the time of interview. This was significantly greater than the estimated population prevalence. Using a Past History Schedule in combination with the PSE, the lifetime prevalence of depressive illness, expressed as the proportion who had ever fulfilled PSE-Catego case criteria, was 38.9%. High rates of psychiatric treatment were also found in family members. The lifetime prevalence of any form of hospital treatment for depression in 315 first-degree relatives was 15.5%. This gives an age-corrected morbidity risk to age 65 years of 24.6%, as compared with a population estimate of 8.9%. In common with previous studies, significantly higher rates of depression were found among female than among male first-degree relatives for broader categories of disorder, but there was a small and nonsignificant excess of men among those relatives who had received in-patient treatment for depression. This apparent lessening of sex differences with more severe categories was not supported by an examination of 'lifetime ever' depressive symptoms, where severity was expressed as highest ever PSE-Catego-ID level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Past and present state examination: the assessment of 'lifetime ever' psychopathology.

A Past History Schedule (PHS) for use in conjunction with the Present State Examination (PSE) is described. The PHS/PSE interview enables a rating of 'lifetime ever' psychopathology to be performed. It provides good inter-rater reliability, as well as a satisfactory agreement between retrospective interviews and casenote-based assessment of past psychopathology. The PHS has been devised specifically for use in a family-genetic study of affective illness, but the general approach may be applicable to other categories of psychiatric disorder.

Humans↗
PubMed1985

Orthostatic effect of imipramine and doxepin in depressed geriatric outpatients.

Blood pressure measurements were collected from 36 depressed geriatric outpatients (ages 55 to 81 years) enrolled in a double-blind, placebo-controlled study of the efficacy of doxepin and imipramine. Mean systolic postural changes were 25.9 mm Hg for imipramine, significantly higher than the 10.5 mm Hg for doxepin, and 12.4 mm Hg for placebo. The orthostatic drop in the imipramine group was only weakly related to dose and did not correlate with amount of pretreatment orthostatic hypotension or with duration of treatment. The increased orthostatic hypotension occurred early in treatment and at low doses of imipramine. Accordingly, caution is advised in the use of imipramine for the elderly.

Age Factors↗
PubMed1984

The effects of a partially purified fraction of an ant venom in rheumatoid arthritis.

A partially purified extract of an ant venom from the South American tree ant Pseudomyrmex sp. was tested in a double-blind, controlled study of patients with rheumatoid arthritis. Venom treated patients demonstrated an improvement in global efficacy and a decrease in the number of tender/painful joints and swollen joints. Swollen joint index improved in 60% of venom treated patients. Other parameters did not demonstrate significant change. Reduction of joint swelling was followed by symptomatic improvement that was sometimes delayed by weeks. Reactions were limited to erythema at the injection site (all patients), local pruritus (two-thirds of the patients), and fever with malaise (one-third of the patients). Further study of this venom in rheumatoid arthritis appears warranted in view of its apparent favorable efficacy-to-toxicity ratio.

Adult↗
PubMed1983

Purchasing power of U.S. Social Security benefits abroad, 1970-82.

This article examines whether the small number of Social Security beneficiaries living abroad enjoy a higher standard of living than they would with the same benefits if they lived in the United States. The article addresses this question using two methods. First, absolute comparisons of U.S. dollar purchasing power abroad are made using "purchasing power parities," a method recently developed to allow international comparisons of real standards of living. Second, the effects of changes in Social Security benefit levels, exchange rates, and rates of inflation on the relative value of benefits abroad are measured. Both methods show considerable instability in purchasing power of Social Security benefits in the 1970's. Although beneficiaries in 1970 generally could live better abroad than in the United States, this advantage eroded considerably during the 1970's, followed by some improvement in 1981-82.

Economics↗
PubMed1982

The earnings replacement rate of old-age benefits in 12 countries, 1969-80.

This article reports the findings of the first cross-national study since 1975 of earnings replacement rates--the proportion of immediate preretirement earnings replaced by social security retirement benefits. In the countries studied--Austria, Canada, Denmark, France, the Federal Republic of Germany, Italy, Japan, the Netherlands, Sweden, Switzerland, the United Kingdom, and the United States--the replacement rates in recent years seem to have continued their upward trend, although they appear to be rising more slowly than before, and under some interpretations seem to be leveling off. In 1980, the United States was fifth among the countries studied in replacement rates for retired couples (one working spouse, one nonworking spouse) and fell within the middle range for single aged beneficiaries: Six countries provided higher benefit levels, four provided lower benefits, and one provided benefits at the same level.

Aged↗