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Publications and source records attributed to S Jones.
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Developing rabbits reutilize the phosphatidylcholine of surfactant with an efficiency of about 95%. The efficiency of reutilization of other components of surfactant have not been determined. 3-day-old rabbits were injected intratracheally with [3H]dipalmitoylphosphatidylcholine (DPPC) mixed with unlabeled natural surfactant and either disaturated [32P]phosphatidylglycerol (DSPG) or [14C]dipalmitoylphosphatidyl-ethanolamine (DPPE). The recovery of [3H]DPPC, [14C]DPPE, and [32P]DSPG in the alveolar wash was measured at different times after injection. By plotting the ratio of [32P]DSPG to [3H]DPPC or [14C]DPPE to [3H]DPPC counts/min in the alveolar wash vs. time after injection we showed that these two phospholipids are reutilized less efficiently than phosphatidylcholine. Based on other studies, several assumptions were made about the kinetics of surfactant phosphatidylethanolamine and phosphatidylglycerol. From the slopes of the semilog plots of total [14C]DPPE and total [32P]DSPG counts/min in the alveolar wash vs. time and these assumptions, we determined that these two phospholipids were reutilized at an efficiency of only 79%.
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A 3-month-old female infant had profound generalized weakness, de Toni-Fanconi-Debre syndrome, and lactic acidosis. She required assisted ventilation and died at the age of 8 months. Muscle biopsy showed accumulation of mitochondria, glycogen, and lipid droplets. Histochemical reaction and immunocytochemical stain for cytochrome c oxidase showed very weak results, but both reactions were normal in intrafusal fibers of the muscle spindle. In crude extracts of the patient's muscle, cytochrome c oxidase activity was undetectable and enzyme-linked immunosorbent assay showed decreased reaction at all dilutions of antiserum. These data indicate that the amount of immunoreactive enzyme protein is markedly decreased in muscle of patients with fatal infantile cytochrome c oxidase deficiency and renal dysfunction.
Two phase II trials of mitoxantrone (Novantrone; dihydroxyanthracenedione) in refractory malignant lymphoma have been conducted. In the first of these, mitoxantrone, 5 mg/m2, was given weekly for six weeks and in the second, 14 mg/m2 was administered every three weeks. The first trial was conducted by the Southeastern Cancer Study Group (SECSG) and the second was a multicenter trial sponsored by Lederle Laboratories. Of the 51 patients entered in the SECSG trial, 28 could be evaluated for response and 43 for toxicity. WBC nadirs below 4.0 X 10(9)/litre were recorded in 25 patients. Three partial responses and no complete responses were obtained. These results contrast with those of the single dose every three weeks study in which 96 patients were entered and 69 of these were evaluated for response. Responses were obtained in 30 patients (4 complete, 26 partial). Side-effects on this three-weekly dose regimen were minimal. WBC nadirs below 4.0 X 10(9)/litre occurred in 85 patients. Twenty-three patients experienced at least mild nausea and vomiting and 15 had at least mild alopecia. These preliminary data indicate that mitoxantrone has significant activity in malignant lymphoma. All of the responding patients had received extensive prior therapy, many of them with anthracyclines in combination or as single agents. The higher response rate to mitoxantrone given at 14 mg/m2 every three weeks suggests that careful consideration should be given to dose schedule when this drug is examined further in phase III trials.
Immature newborn rabbits, delivered on day 27 of gestation, were ventilated artificially for 60 min, with or without previous treatment with natural surfactant. Insufflation pressure was adjusted to maintain an average tidal volume of about 10 ml/kg. All animals received, before the onset of ventilation, 125I-labeled albumin via the airways and 131I-labeled albumin intravenously. At the end of the experiment 3.1 +/- 1.3% (means +/- SD) of the 131I-albumin had permeated into the alveolar compartment of control animals; the corresponding figures for surfactant-treated animals were 1.7 +/- 0.8% (P less than 0.002). In control animals only 18.2 +/- 4.4% of the 125I-albumin could be recovered from the airspaces after 60 min, whereas 69.9 +/- 14.6% of this label was recovered in surfactant-treated animals (P less than 0.002). Alveolar wash samples from control animals also contained significantly increased activity of surfactant inhibitor, as evaluated with pulsating bubble. The bidirectional flux of protein, including surfactant inhibitor, was thus significantly decreased in these immature lungs by surfactant replacement.
To determine the utility of tissue section immunochemistry in the evaluation of bone marrow involved by lymphoid and plasma cell malignancies, snap-frozen, undecalcified bone marrow core and aspirate samples from 23 patients with these disorders were studied with a battery of monoclonal antibodies. With techniques that preserve architecture, difficult diagnostic cases characterized by core but not aspirate involvement, or the reverse, were resolved. By means of an extensive battery of monoclonal antibodies applied to serial sections, complex tumor cell phenotypes were established in all 23 cases. In addition to the identification of straightforward monoclonal surface immunoglobulin expression in small cleaved cell lymphomas (four cases), the battery approach added immunologic certainty in malignancies with unusual or difficult phenotypes: peripheral T-cell lymphomas with idiosyncratic antigen expression, and chronic lymphocytic leukemias and small cell lymphomas with faint surface immunoglobulin expression (four cases). For the chronic lymphocytic leukemias and the small cell lymphomas, the combined IgD+, B2+, B1+, Ia+, Leu-1+ phenotype taken as a whole had greater utility than any isolated marker. The acute lymphocytic leukemias and the myelomas studied demonstrate the wide range of B-cell antigens that must be detected to account for the variety of B-cell neoplasms encountered. Additionally, the previously undescribed phenotypic subset of CALLA+ myelomas, which is of prognostic relevance, was identified. Marrow frozen section immunotyping is a major asset in the evaluation of patients with lymphoma, leukemia, and myeloma when special care is accorded to tissue handling and to treatment of endogenous peroxidase/pseudoperoxidase and interstitial immunoglobulin.
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Eleven patients with mature or peripheral T-cell lymphoma (PTL), other than mycosis fungoides, were identified using an extensive battery of T- and B-cell markers. Eight cases had a histologic diagnosis of either diffuse large cell or mixed lymphoma, three of small cell type. All cases had one or more "mature" T-antigens and an absence of B- and immature T-antigens. Assessment of T-antigens included E-rosettes (Er), anti-Leu 1-7 and Tdt. The authors delineated striking heterogeneity of T-antigen expression: 9 different immunotypes in 11 cases. Subset T-antigen assessment indicated T-helper neoplastic cells in five cases and T-suppressor in two. The remaining four had universal T-antigens alone. Seven cases appeared to have "novel" T-phenotypes not corresponding to normal T-ontogeny phenotypes. Novel or idiosyncratic phenotypes may be a key characteristic of PTL. Since no single T-antigen, including Er and Er receptor (Leu-5), was expressed in all cases, a battery of monoclonal antibodies is necessary to detect PTL. Clinically, the authors found PTL unexpectedly aggressive, despite mature immunotype. Most patients were elderly (median age 69); all had extranodal disease with cutaneous involvement (six cases) most frequent. Responses to chemotherapy frequently proved transient, with median survival of nine months. A fulminant course was noted even with localized presentation. Clinical outcome suggests PTL requires new therapeutic strategies.
A case is described of a patient, known to be suffering from idiopathic autonomic neuropathy, who underwent general anaesthesia for repair of a fractured neck of femur. In addition to profound hypotension, unexpected respiratory depression occurred which has not previously been described in this condition. Other unusual features of this patient's condition are also discussed.
Amiodarone-induced cutaneous photosensitivity was studied in 12 subjects treated with the drug. The action spectrum for the abnormal response to sunlight was shown to be within the range of 335-460 (+/- 30) nm. The clinical features of the photosensitivity response suggested that it was most probably a phototoxic reaction, a conclusion supported by the results of in vitro studies which indicated activity mainly against cell membranes. Of the five in vitro models used, three--namely photohaemolysis, the inhibition of DNA synthesis in PHA stimulated lymphocytes and the killing of mouse peritoneal macrophages--provided unequivocal evidence of the phototoxic potential of both amiodarone and its major metabolite, desethylamiodarone. In each model desethylamiodarone produced a greater effect by a factor of between 2 and 10. In vitro, UV-B wavelengths produced a greater effect than UVA but the difference between the effective wavelengths in vivo and in vitro might be explained by the greater absorption of the shorter wavelength UV-B in the epidermis. Zinc oxide-containing preparations appeared to be the most effective in reducing the cutaneous photosensitivity. It is suggested that the long-term cutaneous pigmentation resulting from oral amiodarone has a significant photosensitivity component.
Sultamicillin, an antibiotic combining ampicillin and the beta-lactamase inhibitor sulbactam, was administered to 13 patients diagnosed as having acute sinusitis. Specimens from sinus were obtained for all 13 patients by transantral puncture. Pharmacokinetics, bacteriology, and therapeutic efficacy were assessed. Eighty-five percent (11 of 13) were cured; two treatment failures were subsequently shown to have chronic (rather than acute) sinusitis during surgical exploration. Diarrhea was frequently encountered, and Clostridium difficile-associated enteritis was documented for one patient. Beta-lactamase-producing organisms were not encountered in this study; however, this study provides impetus for further controlled clinical trials.
A patient with cystic fibrosis and undetectable serum vitamin E concentrations is described who developed a progressive spinocerebellar syndrome and pigmentary retinopathy with abnormal somatosensory and visual evoked potentials (SSEPs and VEPs). In order to assess the relationship between neurological function and serum vitamin E concentrations in cystic fibrosis, 29 unselected patients who had no neurological symptoms were examined neurologically. Ten were randomly selected for neurophysiological assessment by recording SSEPs and VEPs. Electroretinograms (ERGs) were also performed in five cases. The findings were correlated with serum vitamin E concentrations which were unknown to the neurological investigators prior to completion of the study. Only one patient had definite reflex and sensory abnormalities, and the remaining 28 were clinically normal. The ERG was abnormal in two cases, one of whom had abnormal VEPs. SSEPs were normal in all 10 cases. Twenty six patients had serum vitamin E concentrations below the normal range. In two of the three patients who had definite neurological or electrophysiological abnormalities serum vitamin E concentrations were below the median value for the whole group.
Pulmonary surfactant (PS) is capable of lowering surface tension at an air-water interface to less than 10 dynes/cm. This property of PS is believed to be important for normal lung function. We tested the detergent Tween 20, which cannot lower surface tension at an air-water interface to less than 25 dynes/cm, for its ability to promote reasonable gas exchange in surfactant-deficient lambs delivered prematurely at 120 to 124 days gestation. Lambs were treated at birth with 75 mM NaCl (control), 5% Tween 20 in 75 mM NaCl, or PS in 75 mM NaCl and placed on infant ventilators. Control lambs had poor oxygenation and were in respiratory failure at 30 min of age (arterial PCO2 of 75.8 +/- 11 mmHg (mean +/- SE)) despite peak inspiratory pressures (PIP) of 32 +/- 0.7 cm H2O. Pulmonary surfactant treatment allowed adequate ventilation with a PIP of 23.8 +/- 1.2 cm H2O. Tween treatment also allowed adequate ventilation with a PIP of only 27 +/- 1.3 cm H2O. Minimal surface tensions in alveolar washes of control and Tween-treated lambs were 28.7 +/- 1.3 and 26.7 +/- 2.3 dynes/cm, respectively, compared with less than 10 dynes/cm for PS-treated lambs. Thus, Tween 20 did not alter the alveolar wash minimal surface tension when compared with that of the control animals but it did significantly improve gas exchange and lung compliance.