Role of vasopressin in regulation of sodium excretion

It has been proposed that arginine vasopressin (AVP) contributes to the regulation of renal sodium excretion by direct intrarenal actions, by neural-hormonal interactions, and via secondary effects of fluid volume retention. The present studies were designed to determine the extent to which the natriuretic effects of AVP are secondary to volume expansion. Three groups of dogs were studied: the first was infused with AVP for 2 weeks in amounts that increased plasma levels from 3 to 15 pg/mL, while water intake was maintained constant by intravenous (iv) water infusion. The second group received the same amount of AVP and was permitted to drink ad libitum. The third group was infused with the same amount of AVP, while total body weight and volume were maintained at a constant level by use of an electronically servo-controlled water infusion system. The results showed a large increase in total body weight (+1.5 kg) and arterial pressure (mean arterial pressure (MAP); +40 mm Hg) in dogs receiving a fixed water intake. This was accompanied by a continuing natriuresis over a 2-week period and severe hyponatremia (115 mEq/L). Dogs allowed ad libitum drinking retained much less fluid (+0.5 kg). MAP was not significantly elevated, and natriuresis did not occur in this group, but hyponatremia was observed (130 mEq/L), and plasma renin activity (PRA) was suppressed. Servo-controlled dogs exhibited no change in MAP, plasma sodium, or PRA, and only a small (-15 mEq) natriuresis occurred on day 1 of AVP infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Histone genes in three sea star species: cluster arrangement, transcriptional polarity, and analyses of the flanking regions of H3 and H4 genes

The arrangement of core histone genes and their transcriptional polarity has been determined for three species of sea stars (Pisaster ochraceus, P. brevispinus, and Dermasterias imbricata) representing two orders which diverged over 500 million years ago. Each species has approximately 500 core histones cluster repeats per haploid genome. The close phylogenetic relationship between the Pisaster species is evident from the correspondence of restriction sites in the repeat element, identical arrangement of core histones, and high degree of sequence homology in both the coding and spacer regions of the H3 gene. The Dermasterias repeat has the same gene order and transcriptional polarity of core histones, but its restriction map is significantly different. Moreover, the Dermasterias H3 gene has the same amino acid sequence, but in comparison to Pisaster nucleotide sequences, shows a high level of silent substitutions. Analyses of the nucleotide sequence of the 5' and 3' regions surrounding the H3 gene from each species demonstrate the presence of appropriately spaced consensus and processing signal segments. The 3' spacer segment of the Dermasterias H4 gene contains an unusual, threefold tandemly repeated, 21-nucleotide, AT-rich sequence. No similar sequence is seen in the P. brevispinus H4 3' region, but these two species show a striking regularity of distribution of five different homologous oligomers in the 3' spacer.

The arthropathy of cystic fibrosis

Musculoskeletal symptoms are frequent in cystic fibrosis (CF). Here the clinical features of 29 patients with CF who had significant arthropathy are described. Twelve had episodic arthritis (EA) characterised by repeated short attacks of severe, incapacitating polyarthritis, which in seven was associated with fever and erythema nodosum. Ten patients had hypertrophic pulmonary osteoarthropathy (HPOA). The onset of symptoms in the group with HPOA was usually later (mean age 20 years v 16 years for EA) and was associated with significantly worse lung function than in patients with CF, either without arthropathy or with EA. Seven patients had arthropathies which could not be classified as EA or HPOA.

The role of home care service in family care of developmentally disabled children: an exploratory study

Recent concern about the needs of developmentally disabled children living at home has led to increased attention to family support programs. Home care service is one family support option which should be viewed as a basic fundamental support strategy. An exploratory study of a small number of families caring for developmentally disabled children in New York City indicates that publicly-funded home care produces a great number of benefits for this special population.

Dose-dependent interaction between cholecystokinin and sham feeding

Previous work in this laboratory indicated that decreases in feeding motivation produced by cholecystokinin octapeptide (CCK-8) develop through synergism with signals generated by feeding. In these experiments, we used a runway paradigm to assess the contribution of signals from the oral cavity to this interaction. In contrast to the substantial (44%) impairment in runway performance produced by the combination of 1 microgram/kg CCK-8 and 5 min normal prefeeding, 5 min sham feeding failed to potentiate the effect of 1 microgram/kg CCK-8. Sham feeding in conjunction with this dose of CCK-8 reduced running speed by no more (2%) than CCK-8 alone (9%). Similar results were obtained whether rats were allowed a longer sham feeding interval (12 min) or the prefeeding interval was shifted in time so that it ended only 3 min before the start of the runway test. By contrast, larger doses of CCK-8 interacted with 5 min sham feeding to substantially impair runway performance; significant decreases in speed of 29% and 41% were observed after 2 and 4 micrograms/kg CCK-8, respectively. Results with these doses indicate that synergy between CCK-8 and signals from the oral cavity can contribute to the inhibitory effects of this agent. However, the failure of the combination of the 1 microgram/kg dose and sham feeding to replicate the interaction seen with normal prefeeding indicates the additional involvement of signals arising from food stimulation distal to the oropharynx.

Intraoperative Polaroid roentgenograms

The introduction of a new Polaroid film (TPX) prompted an evaluation of all Polaroid films that are available, and a comparison with Kodak Xomat film was done both in the experimental mode and the clinical situation. Type TPX shows excellent definition but is still an experimental film. All the other Polaroid films (Types 52, 57, and TPX 10 x 8) produce images in twenty seconds. This is really the only advantage over the conventional Kodak X-Omat KS film processed as an x-ray film.

Norepinephrine metabolism in humans. Kinetic analysis and model

The present study was undertaken to quantify more precisely and to begin to address the problem of heterogeneity of the kinetics of distribution and metabolism of norepinephrine (NE) in humans, by using compartmental analysis. Steady-state NE specific activity in arterialized plasma during [3H]NE infusion and postinfusion plasma disappearance of [3H]NE were measured in eight healthy subjects in the supine and upright positions. Two exponentials were clearly identified in the plasma [3H]NE disappearance curves of each subject studied in the supine (r = 0.94-1.00, all P less than 0.01) and upright (r = 0.90-0.98, all P less than 0.01) positions. A two-compartment model was the minimal model necessary to simultaneously describe the kinetics of NE in the supine and upright positions. The NE input rate into the extravascular compartment 2, estimated with the minimal model, increased with upright posture (1.87 +/- 0.08 vs. 3.25 +/- 0.2 micrograms/min per m2, P less than 0.001). Upright posture was associated with a fall in the volume of distribution of NE in compartment 1 (7.5 +/- 0.6 vs. 4.7 +/- 0.3 liters, P less than 0.001), and as a result of that, there was a fall in the metabolic clearance rate of NE from compartment 1 (1.80 +/- 0.11 vs. 1.21 +/- 0.08 liters/min per m2, P less than 0.001). We conclude that a two-compartment model is the minimal model that can accurately describe the kinetics of distribution and metabolism of NE in humans.

Pneumothorax in the supine patient

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Two regions downstream of AATAAA in the human antithrombin III gene are important for cleavage-polyadenylation

We have investigated the sequence requirements for the cleavage-polyadenylation reaction in the human antithrombin III (ATIII) gene. A series of 5'-3' and 3'-5' deletions were produced around the AATAAA site using Bal31 nuclease. Ligation of appropriate pairs of such mutations resulted in the generation of varying sized deletions or duplications of sequences either upstream of, downstream of, or within the region encompassing the poly(A) site. Whereas a large deletion 3' to the AATAAA signal abolished cleavage and polyadenylation of ATIII transcripts, smaller deletions, all of which were subsets of the large one, did not. This indicated that the ATIII gene contains at least two independently acting poly(A)-cleavage signals 3' of AATAAA. When one of these signals was eliminated and the other was partially deleted at its 3'-end, we were able to disrupt the normal spacing between AATAAA and the cleavage site without substantially affecting the efficiency of the cleavage reaction. This suggested that the distance between AATAAA and the cleavage site is determined by the same sequence which, along with AATAAA, specifies cleavage and polyadenylation. The duplication of regions either upstream or downstream of AATAAA affected neither the efficiency nor the site of cleavage of the ATIII transcript. When a duplication included a large region containing AATAAA as well as downstream sequences, both sites were chosen for cleavage reactions. With a more delimited duplication, which included AATAAA but not the downstream cleavage signals, both sites were again used. However, two new cleavage sites were now detected. These results suggested that the distance between AATAAA sites and critical downstream cleavage-spacing sequences may also be important in determining the site of cleavage. This may in part stem from spatial constraints imposed by RNA-protein complexes which have been postulated to be critical in catalyzing the cleavage-polyadenylation reaction.

Visualization of the intact endoplasmic reticulum by immunofluorescence with antibodies to the major ER glycoprotein, endoplasmin

Antibodies to endoplasmin were used to examine the morphology of the endoplasmic reticulum (ER) by immunofluorescence on permeabilized plasmacytoma and fibroblastoid cells. In unfixed cells, permeabilization led to a pronounced vesiculation of the ER. Therefore cells were first fixed lightly prior to permeabilization with detergent. Fibroblastoid cells gave a characteristic reticular pattern surrounding the nucleus with clear staining of the nuclear membrane. Plasmacytoma cells, in the conventional fluorescence microscope, gave a cisternae-like pattern. Optical sectioning with a confocal scanning laser microscope gave a distinct pattern of concentric cisternae similar to those obtained with transmission electron microscopy on cell sections. The overall morphology of the ER in such cells could be revealed by serial optical sectioning. Evidence was obtained that the ER does not undergo extensive vesiculation during mitosis in plasmacytoma cells. Using anti-endoplasmin immunofluorescence monitoring, conditions were developed for the retention of ER morphology in unfixed, permeabilized cells. These studies illustrate the value of endoplasmin as a general marker for the analysis of ER morphology in different types of cells by immunofluorescence microscopy.

Mechanism of attenuated hydrochlorothiazide response during indomethacin administration

Indomethacin antagonizes the natriuretic and chloruretic response to hydrochlorothiazide in most studies. Neither the mechanism nor nephron site of this antagonism has been determined. To identify sites and potential mechanisms, cortical micropuncture was performed during hydrochlorothiazide treatment in control and indomethacin rats. Indomethacin reduced (P less than 0.005) FeCl from 5.20 +/- 0.49% to 2.26 +/- 0.49% (mean +/- SE). MAP, CIn, and plasma volume were not different between groups. SNGFR and fractional proximal fluid and chloride delivery were not different between groups. Fractional chloride delivery to early distal tubules was 10.8 +/- 0.4% in control but 6.2 +/- 0.3% in indomethacin rats (P less than 0.001). Calculated loop chloride reabsorption was greater in indomethacin than control rats during hydrochlorothiazide administration (41.0 +/- 1.6% vs. 34.3 +/- 2.3%; P less than 0.05). Fractional chloride delivery to late distal tubules was 7.8 +/- 0.7% in control and 4.6 +/- 0.3% in indomethacin rats (P less than 0.005), but distal tubule chloride reabsorption was not different between groups. Papillary tissue chloride was less in control than indomethacin rats during hydrochlorothiazide (P less than 0.05). Urinary PGE2 excretion was reduced (P less than 0.001) by indomethacin during hydrochlorothiazide. Thus indomethacin induced reductions in hydrochlorothiazide response result in part from increased chloride reabsorption in the loop segment. This suggests indomethacin antagonizes hydrochlorothiazide by reducing chloride delivery to hydrochlorothiazide's site of action in the distal tubule rather than by effects of indomethacin on hydrochlorothiazide pharmacokinetics.

Lymphocyte subpopulations and function in cystic fibrosis

Circulating lymphocytes subpopulations and their function have been studied in 25 young adults with cystic fibrosis (CF) and 25 normal controls. Mean absolute numbers of all lymphocyte subsets in the CF group were not significantly different from the controls. Antibody-dependent cell cytotoxicity was significantly higher in the CF patients who had Pseudomonas aeruginosa in their sputum compared with those who had not and compared with the normal controls. Within the CF group the numbers of B cells, total T cells and OKT4+ helper cells fell as percent predicted peak expiratory flow (PEF) declined and similar significant positive correlations were found between lymphocyte subsets and percent predicted body weight. Serum albumin levels also showed a positive correlation with total T lymphocyte numbers (p less than 0.05). In vitro lymphocyte proliferative responses to mitogen were not significantly different from the control group, but again correlated positively with body weight in the CF patients. This provides further evidence that immune function in CF patients may become impaired as pulmonary disease and nutritional status deteriorate.

Isolation and identification of partial cDNA clones for endoplasmin, the major glycoprotein of mammalian endoplasmic reticulum

The amino acid sequences of peptides isolated from murine endoplasmin showed significant homology (approximately 50%) with sequences in the heat-shock proteins 90 and 83 of yeast and Drosophila, respectively, indicating that they are related proteins. Mixed oligonucleotide probes, deduced from the peptide sequences, were used to isolate cDNAs from a murine liver cDNA library. DNA sequencing confirmed the presence of a coding sequence for one of the endoplasmin peptides, formally establishing the authenticity of the cDNA. The identity of the murine and hamster endoplasmin sequences suggests a level of sequence conservation associated with proteins that perform a structural role in cells.

Differential expression of murine macrophage surface glycoprotein antigens in intracellular membranes

A monoclonal antibody recognizing a novel murine macrophage glycoprotein antigen (MAG) was prepared by the hybridoma technique. Using live and permeabilized macrophages to estimate surface and total MAG, respectively, it was found that at least 50% of the total antigen was intracellular. In contrast, another macrophage surface glycoprotein antigen, Mac-1, was undetectable in the intracellular pool. Immunofluorescence studies confirmed the existence of a substantial intracellular pool of MAG antigen. Similar results were obtained with a panel of cultured tumour cell lines. In one such cell line, it was shown that surface MAG existed in a distinct punctate pattern indicative of microdomains, whereas surface Mac-1 antigen gave a uniform distribution. The possible role of the surface microdomains in the differential expression of the two surface glycoproteins in intracellular membranes is discussed.

Oral ciprofloxacin compared with conventional intravenous treatment for Pseudomonas aeruginosa infection in adults with cystic fibrosis

40 adult patients with cystic fibrosis (CF) were admitted to hospital with acute exacerbations of infection associated with isolation of Pseudomonas aeruginosa from sputum. The patients were randomly allocated (20 per group) to receive intravenous azlocillin 5 g and gentamicin 80 mg, or oral ciprofloxacin 500 mg. Both treatments were given three times a day for 10 days. The patients were assessed on days 1 and 10, and at 6 weeks. There was a significant improvement in lung function between days 1 and 10 in both groups (p less than 0.001). Significant improvement was maintained at 6 weeks after ciprofloxacin but not in the intravenous group. Improvement after ciprofloxacin was superior at day 10. Sputum weight decreased in both groups (p less than 0.001). Patient-recorded symptoms also improved in both groups. There was no serious toxicity or side-effects. Drug resistant organisms were isolated no more frequently after ciprofloxacin than after intravenous therapy. 17 of the ciprofloxacin-treated patients said they preferred oral treatment to intravenous therapy. Oral ciprofloxacin is a useful short-term treatment for patients with CF who are infected with Ps aeruginosa.

Treatment of incarceration of the penis by tempered steel bushings

A case of penile incarceration secondary to a tempered steel ball bearing compromising the penile vascular supply is presented. The management of this case is described and guidelines for the management of similar cases reviewed.

A monocyte function test (complement receptor enhancement) to assess the extent of bronchial carcinoma

A monocyte function test (complement receptor enhancement) was undertaken on 45 patients with suspected bronchial carcinoma in whom this diagnosis was subsequently substantiated. In 38 (84%) complement receptor enhancement was below a range of values previously established for monocytes from 48 healthy control subjects and from 12 patients with non-malignant respiratory diseases. It was found that all 38 patients with reduced complement receptor enhancement had either local or widespread metastases, as determined by the chest radiograph and a variable combination of chest tomography, liver, bone and brain scanning, computed tomography, fibreoptic bronchoscopy, bone marrow aspiration, liver function tests, mediastinoscopy, and surgical assessment, where appropriate. By contrast, at the time of presentation there was no clear relationship between abnormal values in several conventional screening haematological or biochemical tests and the stage of the tumour. These results suggest that complement receptor enhancement might serve as a useful pointer to the extent of the disease, since low values were associated with extension within the chest and very low values were found with widespread metastases.

Twice daily beclomethasone dipropionate administered with a concentrated aerosol inhaler: efficacy and patient compliance

The efficacy of twice daily inhaled beclomethasone dipropionate administered by a concentrated aerosol inhaler (one puff twice daily-500 micrograms/day) has been compared with that of treatment four times daily with a standard dose inhaler (two puffs four times daily-400 micrograms/day) in 21 patients with stable asthma. Double placebo inhalers were used in a randomised crossover fashion during two four week treatment periods. Mean peak expiratory flow (PEF), mean symptom scores, and number of extra salbutamol inhalations required were not significantly different between the two treatment periods. Local side effects were more common during treatment with the four times daily active preparation; overt oropharyngeal candidiasis, however, was not found in either group during the study. On completion of the crossover study patients were transferred to the twice daily regimen. At the three month follow up all patients had remained stable and the outpatient PEF was significantly higher (mean 382 (SD 26)l min-1) than at entry into the trial (mean 345 (24)l min-1) (p less than 0.05). Twice daily beclomethasone administered by a concentrated aerosol inhaler appears to be as effective as the standard four times daily regimen in controlling stable asthma.

Effective and reliable behavioral control technology

The fiberglass-reinforced plastics industry and the literature on controlling exposures to toxic substances were surveyed to select work practices and housekeeping conditions that might be useful in reducing workers' exposures to styrene. A training program was developed to teach the selected behaviors to workers, and a behavior maintenance program was developed to encourage their continued use after training. These behavioral controls were introduced to appropriate workers in three different plants and were effective in changing all selected behaviors and conditions. Statistically reliable reductions in workers' exposures to styrene accompanied the changes in behaviors. All improvements were maintained throughout the course of data collection. The research provides a clear demonstration that behavioral controls can be used reliably to reduce workers' exposures to toxic substances.

Human-environment process: a test of Rogers' principle of integrality

Rogers' principle of integrality was examined through testing the hypothesis that healthy subjects who are confined to bed in a varied harmonic environment will perceive themselves to be more rested than those subjects confined to bed in quiet ambient environment. A two-group pretest-posttest design was used to gather data to test the hypothesis. The findings of the study revealed that the hypothesis was supported beyond the 0.05 level of significance. The integrity of the mutual human-environment field process was strengthened with an environment of varied harmonic sounds.