Adriamycin, BCNU plus cyclophosphamide (ABC) in advanced carcinoma of the head and neck

Forty-four patients with advanced carcinoma of the head and neck were treated with cyclophosphamide, 400 mg/m2 plus BCNU, 100 mg/m2 day 1 followed by adriamycin 40 mg/m2 day 2, with therapy repeated every 4 weeks. Of 31 evaluable patients, there were 1 complete response, and 10 partial responses (35%). Four of 8 patients without prior chemotherapy had complete or partial responses, as did 7 of 23 patients who had received prior chemotherapy. The mean survival for patients with partial responses was 8.8 months, and for patients with stable disease was 7.8 months. The mean time to progression for patients with partial responses was 5.4 months, and for patients with stable disease was 3.2 months. Granulocytopenia was the dose limiting toxicity, and patients with increasing degrees of myelosuppression appeared to have higher quality responses and longer survival. The ABC treatment program is useful in the palliative management of patients with advanced carcinoma of the head and neck.

Mechanism of the dipsogenic action of tetradecapeptide renin substrate in dogs

Dogs with chronically implanted third ventricular cannulae showed significant drinking responses to central injections of angiotensin II and tetradecapeptide renin substrate (TDP). The threshold dose for angiotensin II was 1 pmol and for TDP was 70 pmol. Although central injections of TDP led to drinking and appearance of angiotensin II in cerebrospinal fluid, renin substrate prepared from dog cerebrospinal fluid had no effect. The dipsogenic action of TDP was blocked by prior administration of converting enzyme inhibitor SQ20881 (P less than 0.01) but was not affected by either pepstatin or N-acetyl-pepstatin. Thus, converting enzyme acts directly on TDP to produce angiotensin I and then angiotensin II. The results of the present study do not provide evidence for the presence of an enzyme in the brain with renin-like activity.

Comparison of antibodies in marine fish from clean and polluted waters of the New York Bight: relative levels against 36 bacteria

Fish from polluted waters are subject to increased prevalence of disease. Because they respond to bacterial pathogens by producing serum antibodies, it was possible to construct a seasonal serological record in three fish species from clean and polluted waters of the New York Bight. Antibody levels were determined by testing sera for agglutinating activity against 36 strains of bacteria. Evaluation of 5,100 antibody titrations showed the following. During warm months, summer flounder (Paralichthys dentatus) from the polluted area had significantly higher antibody levels and antibody to a greater diversity of bacteria than fish from the unpolluted area. Weakfish (Cynoscion regalis) from the same polluted area shared with summer flounder raised titers to many bacteria. The greatest proportion of raised titers was against Vibrio species, although prominent titers were also seen against Aeromonas salmonicida and Haemophilus piscium, bacteria usually associated with diseases in freshwater but not marine fish. Differences between polluted and clean waters were not as evident in winter flounder (Pseudopleuronectes americanus) during cold months. This could be due, in part, to reduced antibody production at colder temperatures. The data illustrate the usefulness of the serum antibody record in identifying environmental exposure to bacteria in marine fish and indicate that the polluted New York Bight apex has increased levels and diversity of bacteria during warm months.

Pulmonary structural changes following microembolism and blood transfusion. A light and electron microscopic study

Blood stored under standard blood band conditions develops microaggregates of platelets and leukocytes. Dog lungs were studied by light and electron microscopy at intervals from 48 hours to six days following exchange transfusions of sublethal volumes of such microaggregate-rich blood through either standard or Dacron wool (Swank) transfusion filters. After transfusion through standard filters, the pulmonary microvasculature was extensively occluded by microemboli. Swelling of capillary endothelial cells, interstitial and alveolar edema, and hypoxic changes in types I and II alveolar epithelial cells were noted. Changes then progressively resolved. These detrimental changes were prevented when microaggregates were removed by Dacron wool (Swank) filters. Mechanical occlusion of the pulmonary vasculature probably plays a minor role in initiating the structural changes observed. Release of lysosomes from disintegrating microaggregates is believed to be the significant factor initiating a chain of events leading to progressive pulmonary damage.

Inhibition of Escherichia coli K-12 by beta-lactam antibiotics with poor antibacterial activity: interaction of permeability and intrinsic activity against penicillin-binding proteins

The effect of methicillin, cloxacillin, 1078/1/1, penicillin G, and cephaloridine upon the penicillin-binding proteins of a permeability mutant of Escherichia coli K-12 and its isogenic wild type have been investigated. Comparison of the 50% inhibition values for the antibiotics against the penicillin-binding proteins of the two strains with the minimal inhibitory concentrations for the same compounds indicates that methicillin, cloxacillin, 1078/1/1, and to a lesser extent penicillin G, owe their poor antibacterial activity to exclusion from the bacterial cell, whereas cephaloridine is not excluded and is equally active against both the mutant and its wild type. The results further suggest that the lesion in the permeability mutant E. coli DC2 allows free access of all the compounds tested to the inner membrane target proteins.

Endometrial cancer and estrogen use. Report of a large case-control study

Our case-control study of the relation between estrogen use and endometrial cancer involved 451 cases and 888 controls. The overall risk of endometrial carcinoma was sixfold for estrogen users as compared with nonusers; long-term users (greater than five years) had a 15-fold risk. Excess risk was present for both diethylstilberstrol and conjugated estrogens. The risk associated with cyclic use was as great as that for continuous use. Increased risk was associated with estrogen use for all histologic grades of the tumor. The risk of advanced-stage carcinoma was fourfold for estrogen users, but rhe confidence interval was wide, and this question requires further study. Finally, this investigation contradicts the speculation that the association between this cancer and estrogen use can be explained by swifter diagnosis for estrogen users, misclassification of estrogen-related hyperplasia or treatment of early symptoms of the tumor with estrogen.

Effects of adenosine 5'-triphosphate (ATP) and beta-gamma-methylene ATP on the rat urinary bladder

1 High concentrations of adenosine 5'-triphosphate (ATP, 100 to 1000 micrometer) were required to cause contraction of the rat urinary bladder, while adenosine and adenosine 5'monophosphate (AMP, 1 to 50 micrometer) produced relaxation. 2 One hundred fold lower concentrations of beta-gamma-methylene ATP, which is resistant to degradation to AMP and adenosine, caused dose-dependent, phasic contractions which mimicked atropine-resistant responses to nerve stimulation. 3 Adenosine and AMP caused dose-dependent inhibition of carbachol-induced contractions; theophylline competitively antagonized this inhibition but not the contractile responses to beta-gamma-methylene ATP, ATP or atropine-resistant nerve stimulation. 4 These results suggest that the insensitivity of the rat bladder to ATP is due to its rapid degradation to AMP and adenosine and support the hypothesis that the bladder receives a purinergic excitatory innervation.

Use of dilute drug solutions for routine cycloplegia and mydriasis

Clinic patients and students were given several regular drops of commercial 10% phenylephrine HCl, and 1.0% cyclopentolate HCl or 1.0% tropicamide HCl. The drops were given three times at five-minute intervals. Mydriasis and cycloplegia were determined and compared with the results obtained by using one of the following: microdrops (0.005 or 0.01 ml) of a mixture of 5% phenylephrine HCl and 0.5% tropicamide HCl, or regular drops of mixtures of 1% phenylephrine HCl, or 0.4% hydroxyamphetamine hydrobromide with 0.1% cyclopentolate HCl, or 0.1% tropicamide in a vehicle of 1.6% or 1.0% methylcellulose 400, or artificial tears or lubricants (Absorbobase, Contique, Isopto Tears, Liquifilm, Lyteers, Ultra Tears). Except for an initial lag in the production of mydriasis with the diluted mixtures, the results were similar for all preparations. The diluted solutions produced little ocular irritation or tearing.

Evaluation of weighted discriminating power calculations as an aid to the selection of chromatographic systems for the analyses of drugs

In toxicological analyses some chromatographic separations are more important than others. Two weighting methods for chromatographic data are described which incorporate the importance of particular separations into discriminating power calculations. The data were abstracted from a publication on the separations of acidic drugs on thin-layer chromatographic systems. When compared with non-weighted discriminating power calculations, those obtained with the weighting procedure did not give any advantage.

Adrenal responses to pharmacological interruption of the renin-angiotensin system in sodium-restricted normal man

We assessed the role of the renin-angiotensin system in the control of aldosterone secretion in response to sodium restriction in 62 normal subjects. Both saralasin, an angiotensin II antagonist, and SQ 20881, a converting enzyme inhibitor, induced a dose-related decrease in plasma aldosterone levels when the renin-angiotensin system was activated by restriction of sodium intake. Two types of experiments were performed with saralasin. In the first set, a dose-response relationship was established 20 min after beginning infusions ranging from 0.03-1.0 microgram/kg/min. The optimal dose was 0.1 microgram/kg/min, with a reduction in aldosterone levels of -10.1 +/- 3.8 ng/dl (P less than 0.025). Higher doses induced smaller reductions in aldosterone levels. In the second set, a 3-h infusion was given. The results were qualitatively similar but the magnitude was greater (-15 +/- 4 ng/dl; P less than 0.01). The aldosterone response 20 min after administration of SQ 20881 paralleled the angiotensin II response, with the first significant decrement (-6.5 +/- 1.5 ng/dl; P less than 0.01) occurring at 0.1 mg/kg and maximum (-10 +/- 3 ng/dl) occurring at 0.3 mg/kg. Thus, both agents produced qualitatively similar changes in aldosterone secretion in sodium-restricted normal subjects. However, neither reduced sodium restricted aldosterone levels to that measured in sodium-loaded subjects because of the intrinsic limitation of each agent. Saralasin is a partial agonist. SQ 20881 induces an increase in plasma renin activity via interruption of the short feedback loop, which probably limits its action. Yet, these data do support the hypothesis that angiotensin mediates the adrenal's response to sodium restriction in normal man.

Physical examinations in inner-city preschools

This paper describes the physical examination program started in March 1974 and carried out by the Anacostia Headstart Program in Washington DC. Annual totals of 362, 274, and 458 preschool children were examined in 16 schools during the 1973-1974, 1974-1975, and 1975-1976 school years, respectively. For these years, 8, 9, and 12 percent, respectively, had heart murmurs. The rates for abdominal hernias were higher, 11, 17, and 16 percent, respectively. Eczema was also a common problem. Parents had easy access to counseling from health professionals who worked in the program.

Modified peptidoglycan transpeptidase activity in a carbenicillin-resistant mutant of Pseudomonas aeruginosa 18s

A carbenicillin-resistant mutant of Pseudomonas aeruginosa 18s was found to possess peptidoglycan transpeptidase activity significantly more resistant to inhibition by benzyl penicillin, ampicillin, carbenicillin, and cephaloridine than that of the parent strain. The mutant was more resistant than the parent strain to all of the beta-lactam antibiotics tested, and 50% inhibition values for these compounds against membrane-bound model transpeptidase activity paralleled this increase. The resistance of the mutant to kanamycin, streptomycin, and chloramphenicol was unchanged.

Development of information processing in normal and disabled readers

8- and 11-yr-old reading-disabled children were compared in two experiments with controls matched on intelligence and age. Exp. 1 measured duration of visual information store by means of a separation threshold technique. Exp. II determined the rate of transfer from visual information store to short-term memory using a backward masking technique. Results from Exp. I showed that at each age specific reading-disabled children had significantly longer durations of visual information store than controls. The difference between the reading ability groups decreased with increasing age. Exp. II demonstrated that rate of transfer of information was significantly slower for specific reading-disabled children than for controls at both age levels. In contrast to Exp. I, this difference increased with increasing age. The results are considered in terms of their possible relevance to developmental lag theories. The evidence indicates that the development of visual information processing in reading-disabled children is similar to that in controls but occurs at a slower rate.

A study of five year old children born after elective induction of labour

A controlled retrospective study of some short-term and long-term effects of elective induction of labour was conducted. There did not appear to be any increase in the incidence of maternal complications during labour, or of neonatal problems in the induced-labour group compared with the remainder of the mothers in the hospital. In the follow-up phase of the study, two treatment groups of children who were delivered after amniotomy and amniotomy plus the administration of oxytocin were compared with each other, and with a control group of children born after spontaneous labour. The children were assessed at the age of five years on verbal and non-verbal subtests of a standardized intelligence scale, tests of gross motor and fine motor coordination, and auditory and visual tests. A full physical examination was also performed. No statistically significant differences nor trends of clinical interest were found between the groups on any measure.

Renal vascular response to interruption of the renin-angiotensin system in normal man

We assessed the role of the renin-angiotensin system in the response of the renal circulation to restriction of sodium intake in 38 normal patients. Both saralasin (10 to 30 ng/kg/min), an angiotensin antagonist, and SQ 20881 (30 to 300microgram/kg), a converting enzyme inhibitor, induced a dose-related increase in renal blood flow (xenon 133 washout) only when the resin-angiotension system was activated by restriction of sodium intake to 10 MEq/day. Increasing doses of saralasin (100 to 1,000 ng/kg/min) reduced renal blood flow, presumably due to the angiotensin-like action of this partial agonist. The renal vascular response to SQ 20881 paralleled the endocrine response: An identical threshold dose (30 microgram/kg) increased renal blood flow and reduced plasma angiotensin II concentration, which fell despite a progressive rise of plasma renin activity. Plasma bradykinin concentration did not change in response to SQ 20881, which also blocks kininase II. Both agents also induced a small but consistent and statistically significant reduction in arterial blood pressure, which will be important in assessing the pathogenetic significance of a blood pressure reduction in patients with hypertension. This study indicates that angiotensin mediates the renal vascular response to restriction of salt intake in normal man and provides an approach to assessing the role played by angiotensin in the pathogenesis of functional renal disease.

Tests for homogeneity of effect in an epidemiologic investigation

A test for homogeneity of the effect of a factor in inducing disease in the various strata of a population should relate to the scaling in which homogeneity is anticipated. Popularity, it is the multiplicative effect on the odds ratio in which homogeneity is anticipated. An asymptotic test by M. Zelen (Biometrika 58:129-137, 1971) for homogeneity in this scaling is indicated to be invalid. Further, a test by J. L. Fleiss (Statistical Methods for Rates and Proportions. NY, Wiley, 1973) for homogeneity of the standardized difference is shown to be the same as the Zelen test, to be invalid in any case, and not to correspond to any scaling. The examples given include one in which results of two studies are apparently inhomogeneous by the test even though they give effectively identical results. It is advised that tests for homogeneity be conducted with care, and that thought be given to how effects might be made homogeneous rather than to trying to demonstrate the existence of heterogeneity.

Release of Escherichia coli DNA from membrane complexes by single-strand endonucleases

Treatment of gently prepared lysates of Escherichia coli with single-strand-specific endonuclease (SI or from mung beans) results in the release of about 90% of the DNA from membranes, as determined by the M band technique. The released DNA has an average molecular weight of about 1.2 X 10(8). Data obtained with endonuclease S1 fit a mathematical model in which substrate sites are at or near membrane attachment sites. Data obtained with pancreatic deoxyribonuclease or x-rays fit a model for double-strand breaks at random sites along the DNA. Fitting data to these models, we estimate that there are 18+/-5 membrane attachment sites. The DNA remaining after S1 nuclease treatment is enriched for the region near the origin of chromosome replication. Therefore, attachment at this region near the origin of chromosome replication. Therefore, attachment at this region appears to be chemically different from that at the other sites along the DNA.

Polyurethane foam (Bentley) micropore blood transfusion filter: filtration characteristics

Stored human blood of varying age was passed through polyurethane foam (Bentley) micropore blood transfusion filters. Passage through these filters resulted in decreased screen filtration pressure (SFP) of the blood and increased filter weights. Numerous microaggregates were removed and SFP returned to normal after filtration. Occlusion of the filter occurred after passage of only 2 units of whole blood. On the basis of this research, we conclude that polyurethane foam (Bentley) micropore blood transfusion filters are effective in removal of microaggregates from stored human blood. Because the filtering capacity is not great, it is recommended that when these filters are used during transfusion a new filter be used for each unit of blood administered.