Aphasia in multiple sclerosis: clinical and radiologic correlations

Aphasia is not commonly reported in multiple sclerosis (MS). We report on two clinically definite MS patients, with a remitting-relapsing course, who presented with acute onset of aphasia. MRI demonstrated giant plaques in the left frontal region in one and in the left centrum semiovale in the other. These lesions were not evident in MRI performed several months previously, and may account for the aphasia. In both patients, language functions markedly improved within several weeks. In one patient, follow-up MRI 3 months later revealed a moderate reduction in the size of the plaque.

Tissue-specific expression of the mouse alpha 2(I) collagen promoter. Studies in transgenic mice and in tissue culture cells

We sought to determine the cis-acting elements responsible for the pattern of tissue specific expression of the mouse alpha 2(I) collagen gene. Using an RNase protection assay we first verified that expression of the alpha 2(I) collagen gene is mainly confined to tendons, bone, and skin in mice. Both transgenic mice and DNA transfection of tissue culture cells were used as experimental approaches. Transgenic mice lines were generated harboring chloramphenicol acetyltransferase (CAT) chimeric genes that contained either (a) 2000 base pairs (bp) of 5'-flanking sequences of the mouse alpha 2(I) collagen gene plus additional sequences between +418 and +1524 of the first intron of this gene or (b) the same promoter sequences without intron sequences or (c) the 350-bp proximal promoter sequences. Transgenic mice containing both types of 2000-bp promoters showed a pattern of CAT expression that was tissue specific. The presence of sequences of the first intron in the transgene did not increase the level of promoter activity. Transgenic mice harboring the 350-bp alpha 2(I) collagen promoter also showed a pattern that was tissue-specific except that high level expression also occurred in the brain. This suggests that negative regulation is an important component of tissue-specific expression. In order to analyze the first 350 bases in detail, we performed transient expression experiments, using promoter fragments attached to the luciferase reporter gene. Fibroblasts, which show a high level expression of the endogenous alpha 2(I) collagen gene, and B cells, in which the gene is silent, were transfected with a series of deletions and substitution mutations within the proximal 350-bp promoter. These experiments were unable to define unique cell-specific cis-acting elements. However, when the sequence between -315 and -284 was tandemly repeated upstream of a minimal alpha 2(I) collagen promoter (-41 to +54), the activity of this construction was considerably higher in fibroblasts than in B cells when compared with the minimal promoter itself. In gel retardation assays, the levels of complexes that bind to this sequence were higher in fibroblast nuclear extracts than in myeloma nuclear extracts. Our results are consistent with the hypothesis that the -315 to -284 DNA sequence participates in the cell-specific control of the alpha 2(I) collagen gene in fibroblasts.

Health of the public. The academic response. Health of the Public Mission Statement Working Group

Aging of the population, increasing prevalence of chronic and disabling illnesses with multiple social and behavioral risk factors, concern about quality of care, and escalating costs of medical care require fundamental changes in the way that academic health centers discharge their mission. This article describes a newly developed "Mission Statement" for academic health centers that wish to contribute positively to the health of the populations that they serve. A shift toward addressing the needs of the public may produce increasing institutional strength, long-run stability, and enhanced productivity, as well as higher quality, more cost-effective care for patients. Seventeen centers in the Health of the Public Program are currently conducting activities that implement the described mission elements. The goals and objectives described herein create a foundation for change, with more balanced institutional goals, and could turn an emerging confrontation between academe and its public into an opportunity for both.

Transcriptional control mechanisms for the expression of type I collagen genes

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Interactions of [3H]amphetamine with rat brain synaptosomes. I. Saturable sequestration

Previous studies have identified a saturable site of d-[3H]amphetamine sequestration (AMSEQ) in rat brain synaptosomes. The present study characterized AMSEQ with respect to its subcellular, neuronal and regional distributions, ontogenetic development, pharmacological specificity and factors required for its maintenance. Although AMSEQ was reduced when assays were performed in Krebs' buffer incubated at 37 degrees C as compared to assays performed in isotonic Tris-sucrose buffer incubated at room temperature, the pharmacological profiles of AMSEQ were virtually identical under both conditions. AMSEQ was negligible in tissues outside the central nervous system, enriched in synaptosomes and partially reduced by striatal kainic acid lesion, indicating neuronal localization. The distribution of AMSEQ in the central nervous system was heterogenous. Highest levels were present in hypothalamus with progressively lower levels noted in parietal cortex, frontal cortex, striatum, thalamus, hippocampus, midbrain, cerebellum, pons-medulla and spinal cord. With regard to its ontogeny, AMSEQ increased early in neonatal life, reaching adult levels by postnatal day 14. Although the effects of amphetamine to abolish the transynaptosomal pH gradient suggest a possible role for this gradient in the maintenance of AMSEQ, the pharmacological profile of AMSEQ indicates that other factors are involved. An interaction with an intrasynaptosomal acid, such as N-acetylaspartate, may account for AMSEQ maintenance. AMSEQ did not possess a stereospecific preference for either d-(IC50 = 177 microM) or I-amphetamine (IC50 = 173 microM). However, the pharmacological profile of AMSEQ indicated structural specificity with antidepressants being relatively potent inhibitors. The saturation analysis and pharmacological characteristics of AMSEQ (i.e., low affinity and lack of stereospecificity) suggest that AMSEQ may be related to high dose, nonstereospecific effects of amphetamine, such as stereotypy in rats and psychosis in humans. The relative high potency of antidepressants in inhibiting AMSEQ suggests the importance of this phenomenon in the therapeutic effects of these drugs. Furthermore, the link between antidepressants and AMSEQ may provide insight into the comorbidity of major depression and drug abuse.

Survey of exposure to genotoxic agents in primary myelodysplastic syndrome: correlation with chromosome patterns and data on patients without hematological disease

Exposure to genotoxic agents such as insecticides, pesticides, and solvents correlated with abnormal karyotypes and development of acute nonlymphocytic leukemia (ANLL) similar to, but to a lesser degree compared to, patients exposed to irradiation and alkylating drugs in several reports. Because of the natural progression of myelodysplastic syndrome (MDS) to ANLL, we investigated the relationship of exposure to these carcinogens in patients with primary MDS by having 52 such patients diagnosed and referred to our center answer an occupational/environmental questionnaire. We excluded all secondary MDS patients with exposure to previous chemotherapy and radiation for a previous malignancy. In addition, we prospectively gave the same questionnaire to a similar number of age- and sex-matched comparable control patients from the same socioeconomic group based on their residence, health insurance coverage, and occupation. We found a 46% exposure rate to implicated genotoxic agents in our patients with MDS. Patients with MDS who were exposed had 75% incidence of a poor prognosis French-American-British classification compared to 57% in the nonexposed group but the difference was not significant (P = 0.089). However, the karyotypic abnormalities that were associated with exposure in ANLL were found equally in both exposed (55%) and nonexposed groups (50%) of our MDS patients and our control group had a similarly high exposure rate at 40% to genotoxins. Implicating a relationship between exposure to pesticides and solvents in ANLL and MDS is difficult. All the previous studies indicating such a relationship did not use a control group of patients. Our findings indicate the pitfalls of historical data without investigating the bias of obtaining an exposure history. However, our findings that the majority of our MDS patients came from the middle socioeconomic group which has a high exposure rate as shown by our control group indicate a relationship and that prospective follow-up of the exposed cohort of control patients should be done to determine if ANLL and MDS will increase after a latent period compared to the nonexposed controls.

Urine citrate and renal stone disease

Calcium stone disease is attributable to supersaturation of the urine with calcium and other salts, the presence of substances that promote crystallization and a deficiency of inhibitors of crystallization. Citrate is a potent inhibitor of calcium oxalate and calcium phosphate stone formation whose excretion is diminished in some patients with stone disease owing to idiopathic causes or secondary factors such as bowel disease and use of thiazides. The pH within the proximal tubule cells is an important determinant of citrate excretion. Multivariate analysis has shown that the urine concentrations of calcium and citrate are the most important factors in stone formation. In uncontrolled studies potassium citrate, which increases urinary citrate excretion, appears to be promising as a therapeutic agent for patients with stone disease and hypocitraturia refractory to other treatment. On the other hand, there are potential drawbacks to sodium alkali therapy, such as the precipitation of calcium phosphates.

Cavernous lymphohemangioendothelioma of the right atrium--a case report

The authors report a successful resection of a rare cystic tumor in the right atrium, discovered in an asymptomatic patient with atrial fibrillation. The cystic nature of the tumor was characterized by two-dimensional echocardiogram preoperatively. The site of attachment and movement of the tumor were clearly shown by cine computed tomography preoperatively. The tumor contained numerous endothelium-lined cavernous channels and groups of red blood cells. These features are distinctly different from those of other cystic tumors.

Identification of P-glycoprotein in renal brush border membranes

A monoclonal antibody (C219) that recognizes the P-glycoprotein (Mr = 170,000) in plasma membranes of multidrug-resistant Chinese hamster ovary (CHO) cell lines was used to assay renal brush border membrane (BBM) and basolateral membrane (BLM) fractions for the presence of a cross-reactive polypeptide. The C219 antibody bound to a 155,000 dalton protein in immunoblots of rat BBM but not BLM proteins resolved by sodium dodecyl sulfate gel electrophoresis. The corresponding human kidney BBM and dog kidney BBM proteins had molecular weights of 170,000 and 160,000 respectively. The glycoprotein nature of the renal protein was shown by its sensitivity to N-glycanase treatment which reduced the apparent molecular weight of the dog protein to 120,000. In addition, dog P-glycoprotein could be bound to and eluted from immobilized wheat germ agglutinin. The molecular weight, antibody crossreactivity, glycosidase sensitivity and lectin binding show that this protein is a normal kidney analogue of the P-glycoprotein induced in multidrug resistant cell lines.

Percutaneous needle biopsy of the transplanted kidney: technique and complications

Over 11 1/2 years, 420 percutaneous needle biopsies were obtained from the transplanted kidneys of 205 patients at one institution. The procedure was performed by one nephrologist and 55 nephrology trainees. No limit was placed on the number of biopsies performed on one kidney, and the highest number was seven. The complications were macroscopic hematuria in 28 biopsies, prolonged hematuria (greater than 24 hours) in eight, transient anuria in five, and prolonged anuria requiring surgical intervention in one. Perinephric hematoma occurred in three patients; retroperitoneal hematoma led to compression of the iliac vein in one. None of these complications led to loss of the transplant. It is suggested that the freedom from serious complication is related to the safety of the technique and the precautions applied to preparation of the patient. These are described in detail.

Mesenteric thrombosis following sclerotherapy during vasopressin infusion: mechanism and therapeutic implications

In a series of 602 consecutive sclerotherapies, two cirrhotic patients who had received successful sclerotherapy for control of variceal bleeding while on vasopressin infusions developed mesenteric thrombosis. We found no other cases (in our institution or in literature review) where sclerotherapy or vasopressin infusion alone precipitated mesenteric thrombosis. During vasopressin infusion, there is portal stasis and an increased caudad flow of sclerosant. We suggest that mesenteric thrombosis is a consequence of the combination of these two effects. Direct injection of gastric varices is difficult because of increased postsclerotherapy bleeding, but sclerosis of esophageal varices often leads to their obliteration by the caudad flow of sclerosant. We propose, therefore, that vasopressin infusion during esophageal sclerotherapy may be beneficial in the obliteration of gastric varices. We conclude that (a) in patients without gastric varices, vasopressin infusion increases the incidence of mesenteric thrombosis, and (b) vasopressin infusion during sclerotherapy may enhance the sclerosis of gastric varices.

Long-term results of amiodarone therapy in patients with recurrent sustained ventricular tachycardia or ventricular fibrillation

Four hundred sixty-two patients, all with either documented spontaneous sustained ventricular tachycardia or cardiac arrest unresponsive to other antiarrhythmic drugs (2.6/patient), were treated with amiodarone. Thirty-five patients (7.6%) failed to respond or died during the initial oral or intravenous loading phase. The remaining 427 patients were discharged on treatment with oral amiodarone and followed up for up to 98 months. Recurrence of ventricular tachycardia or sudden cardiac death at 1, 3 and 5 years by life-table analysis was 19%, 33% and 43%, respectively, for patients discharged on amiodarone therapy. The sudden cardiac death rate was 9%, 15% and 21%, respectively, at 1, 3 and 5 years. Side effects were reported by 45% of patients after 1 year, by 61% after 2 years and by 86% after 5 years. Amiodarone was discontinued because of side effects in 14%, 26% and 37% of patients after 1, 3 and 5 years, respectively. Incidence rates of recurrence of arrhythmia, sudden cardiac death and side effects were highest in the early months and then decreased. By multivariate analysis, advanced age, low ejection fraction and a history of cardiac arrest were independent risk factors for sudden cardiac death during amiodarone therapy.

Diagnosis and management of subclavian vein thrombosis occurring in association with subclavian cannulation for hemodialysis

With the aim of improving the diagnosis and treatment of subclavian vein thrombosis, associated with subclavian cannulation for hemodialysis, we performed Doppler examination of the subclavian vein and clinical inspection of the ipsilateral arm at every dialysis in 50 consecutive patients who received subclavian hemodialysis catheters over 1 year. Edema of the arm and disappearance of the subclavian vein bruit correctly detected 3 cases of subclavian vein obstruction which were confirmed by X-ray venograms. All 3 cases failed to respond to systemic heparin, but were successfully recanalized within 36 h with continuous local streptokinase infusion at a rate of 10,000 U in 1 ml/h. In 4 other cases of edema of the arm, Doppler examination correctly predicted patency of the vein, also confirmed radiologically. In 2 cases of thrombosis, there was an underlying stenosis of the left innominate vein close to its union with the superior vena cava. These were dilated by balloon angioplasty; the stenosis recurred in both cases without recurrent thrombosis, and the angioplasty was repeated. Doppler surveillance seems to be a promising aid to the detection of subclavian vein thrombosis from hemodialysis catheters. Local streptokinase infusion is effective in treating thrombosis. Underlying venous stenosis should be looked for because this may be at least partly remediable by balloon angioplasty.

Mechanism of Li inhibition of vasopressin-sensitive adenylate cyclase in cultured renal epithelial cells

We investigated the mechanism for lithium-induced inhibition of vasopressin-stimulated adensoine 3',5'-cyclic monophosphate (cAMP) production in the renal epithelial cell line LLC-PK1. In LLC-PK1 membranes lithium caused direct inhibition of hormone-stimulated adenylate cyclase activity by competing with magnesium. Fifty percent inhibition occurred at 20 mM lithium. The maximum transport activity (Vmax) but not the activation constant (Ka) for activation by vasopressin was altered. Activation by GTP and its nonhydrolyzable analogues was also inhibited by lithium. Furthermore, kinetic studies revealed that the lag phase in the activation of adenylate cyclase by 5'-guanylimi-dotriphosphate [Gpp(NH)p] was prolonged from 1 to 3 min, suggesting an effect of lithium on magnesium-dependent activation of the stimulatory GTP binding protein Gs. The function of the corresponding inhibitory GTP-binding protein Gi, as assessed by GTP inhibition of vasopressin-stimulated adenylate cyclase activity in the presence and absence of pertussis toxin pretreatment, was unaffected. Intact LLC-PK1 cells incubated in 10 mM lithium (approximate urinary concentration in lithium-treated patients) attained an intracellular lithium concentration of 17 mM, which led to a 40% reduction in cAMP formation. Magnesium loading of intact cells with the ionophore A23187 reversed the inhibitory effect of lithium. It is concluded that lithium directly inhibits the activation of vasopressin-sensitive adenylate cyclase in renal epithelia by competing with magnesium for activation of Gs. This direct effect on Gs activation accounts for the inhibitory effect of lithium on cAMP production in the intact cell.

Fatal necrotizing fasciitis following suction-assisted lipectomy

Forty-eight hours following extensive blunt suction lipectomy with 3,000 cc of tissue removed, a 36-year-old woman presented to an emergency room with necrotizing fasciitis of both lower extremities extending over the buttock and to the lower third of the back. Tissue cultures and blood culture grew out a pure culture of beta-hemolytic streptococci. The patient rapidly progressed into a comatose state and, despite extensive debridement and appropriate antibiotic therapy, in addition to hyperbaric oxygen treatments, she died on day 9 of her hospitalization (day 11 following the suction lipectomy). To our knowledge this is the first published mortality reported in the United States following this procedure.

Reduced cyclosporin accumulation in multidrug-resistant cells

Cyclosporin accumulation was reduced by 50% or more in multidrug- resistant CHRC5 CHO cells with high levels of P-glycoprotein expression compared to drug sensitive AuxB1 CHO cells. This difference could be overcome by verapamil which is known to interact with P-glycoprotein and reverse multidrug resistance. The difference in cyclosporin accumulation between sensitive and resistant cells decreased with increasing cyclosporin concentrations suggesting that cyclosporine itself regulated its own accumulation through interaction with P-glycoprotein. Indeed, cyclosporin also reversed differences in vinblastine accumulation between resistant and sensitive cell lines. Since P-glycoprotein is highly expressed in the kidney which is also a target for cyclosporin toxicity, the effects of verapamil on cyclosporin accumulation were studied in two renal cell lines, rat mesangial cells and LLCPK1, cells. Verapamil increased cyclosporin accumulation by approximately 70%. These results suggest that cellular cyclosporine accumulation is regulated at least in part by its interaction with P-glycoprotein.

Selective toxicity of gossypol against epithelial tumors and its detection by magnetic resonance spectroscopy

The antitumor toxicity of gossypol was measured in 6 human carcinoma cell lines and compared with its toxicity against human bone marrow stem cells. Marrow cells were more resistant than any of the tumor cell lines, and tumor cell sensitivity depended on the content of intracellular LDH-M. [31P]-Magnetic resonance spectroscopy showed decline in tumor ATP levels occurring within 24 hours of treatment, suggesting that this non-invasive technique may serve as an early biochemical monitor of gossypol toxicity.

Effect of cow's milk on jejunal mucosal macromolecular barrier in suckling guinea pigs

The assumption that fresh cow's milk may have a direct effect on jejunal mucosal macromolecular permeability was tested in 14-day-old suckling guinea pigs, by in situ luminal perfusion of a proximal jejunal segment with horseradish peroxidase administered either in 0.9% NaCl or in cow's milk. For positive control, a group of guinea pigs previously sensitized to beta-lactoglobulin was similarly perfused with horseradish peroxidase in 0.9% NaCl or in cow's milk at 14 days of age. A segment of the wall of the perfused jejunal loop was processed for peroxidase staining and for examination of the extent and routes of macromolecular absorption by light and electron microscopy. Mucosal exposure to cow's milk was associated with penetration of tracer material across the jejunal epithelium only in the lactoglobulin-sensitized guinea pigs. In guinea pigs with a first-time exposure to cow's milk, no entry of tracer material beyond the brush border surface of the enterocytes was seen. Thus, whereas we could observe absorption of bystander antigens during antigenic challenge of the mucosa in sensitized animals, we found no evidence of a presumptive "permeability factor" in cow's milk that can disrupt the mucosal macromolecular barrier by an acute direct action.

Bordetella pertussis infection: a cause of persistent cough in adults

An enzyme-linked immunosorbent assay (ELISA) for Bordetella pertussis-specific immunoglobulin (Ig)A antibody in serum was used to demonstrate B. pertussis infection. The upper limit of normal for the assay (mean + 3 SD) was established by testing sera that had been collected from a group of healthy blood donors. All 13 patients with clinical whooping cough from whom B. pertussis was isolated and 25.7% of 218 adults, who were aged 18-81 years, who were referred to a consultant physician for the investigation of a persistent cough, had elevated levels of IgA to B. pertussis. The study confirms the B. pertussis IgA ELISA as a sensitive test for the diagnosis of B. pertussis infections and that these infections cause respiratory illness, in particular, persistent cough in adults.

Changes in cerebral blood flow and recovery from acute stroke

We prospectively studied 14 patients with acute cerebral infarctions using serial 133Xenon inhalation cerebral determination (133Xe-rCBF), scored neurological examinations, and neuropsychological testing. All patients underwent the same battery of tests at 3 days, 1 week, 2 weeks, and 4 weeks after cerebral infarction to determine the prognostic value of early rCBF studies and the chronological relationship of changes in rCBF to clinical status. Baseline rCBF within 3 days of symptoms of acute stroke did not correlate with clinical neurological outcome (r = -0.17, p less than 0.30; r = -0.18, p less than 0.28, for the two indices of rCBF used). Among the 11 patients demonstrating neurological recovery, 7 improved at 1 week, significantly before increases in rCBF (p less than 0.05). We conclude that early baseline rCBF does not predict clinical outcome in patients with acute cerebral infarctions and that return of neurological function precedes rather than follows increases in rCBF.

CT body stereotaxis: an aid for CT-guided biopsies

A new body stereotaxic system used to facilitate CT-guided biopsies is described. By scanning through a triangle placed on the patient's skin, the method defines an entry point for the biopsy. An articulating arm is then used to aim the needle at the entry point and hold the needle at the correct angle. The arm can be angled so that complex approaches from one scan plane to another can be made in order to take biopsies of lesions beneath the diaphragm. Using the system, 23 of 25 lesions were hit on the first needle manipulation; two manipulations were needed for each of the other two lesions. In comparison with previous experience, procedure time was decreased and the numbers of needle manipulations and localization scans were decreased 75% and 90%, respectively.

Superficial temporal-middle cerebral artery anastomosis: effects on vascular, neurologic, and neuropsychological functions

In 44 patients, we studied the effects of superficial temporal-middle cerebral artery anastomosis on cerebral blood flow (CBF), neurologic examination, and cognitive functions. At 3 months, there was significant improvement in all variables. At 9 months, CBF was no longer significantly greater, but neurologic examination and cognitive functions had further improved. Patients with TIA had significant postoperative decreases in TIA frequency and did not progress to stroke, but had no significant changes in any variable. In stroke patients, we could not separate the effects of surgery from the natural evolution of changes in CBF and examination after stroke. None of the preoperative measurements predicted postoperative clinical improvement.

The effect of decentralized education versus increased supply on practice location. Experience with physician assistants and nurse practitioners in California, 1972-1982

To improve the geographic distribution of physician assistants and nurse practitioners in California, the Primary Care Associate Program established five community-based training sites in outlying areas while continuing to operate its core program within the San Francisco Bay Area. To evaluate this effort, the authors prospectively compared the employment locations of graduates from both groups, achieving a follow-up rate of 95%. Graduates from community sites were twice as likely to locate first practices outside the Bay Area (91% vs. 43%, P less than 0.05) and in towns with less than 10,000 inhabitants (33% vs. 16%, P less than 0.05). Over the decade, the percentage of graduates practicing outside the Bay Area rose from 0 to 9% for trainees both recruited from and entirely trained within the Bay Area versus 76-84 percent for trainees experiencing any element of decentralization. The slopes of these two lines represent the effect of the increasing supply of graduates on practice location away from Stanford (9%); the distance between the lines, the greater effect of decentralization (73%). Given the goal of statewide deployment of a small number of graduates, decentralization appears to have been an effective approach.

Improved control of bulky prostate carcinoma with sequential estrogen and radiation therapy

Patients with bulky prostate cancer have usually been treated by palliative measures because the likelihood of tumor control with definitive irradiation has been low and the development of distant metastases high. The addition of estrogen to irradiation has not been shown to be of value. However, we believe the method of estrogen administration may have been the cause for the apparent lack of benefit. Estrogen had been started either concurrent with irradiation or had been used for palliation and was given for long and unscheduled time periods prior to irradiation. We have used estrogen for two months prior to and concurrent with irradiation. We postulated that in those patients with estrogen responsive cancer, the reduced tumor burden prior to irradiation could enhance tumor control and survival. Between 1975 and 1980, 25 patients with bulky prostate cancer received sequential estrogen and irradiation, 12 patients irradiation alone and six patients irradiation after having become refractory to long-term estrogen use. One patient was lost to follow-up. Eighteen of 25 (72%) treated by sequential estrogen and irradiation, 14/17 (82%) with estrogen responsive cancer and 4/8 (50%) with estrogen resistant cancer had a complete tumor response. Six of 11 (55%) patients treated by irradiation alone and 2/6 (33%) treated by irradiation for estrogen refractory cancer had a complete tumor response. Disease-free survival was observed in 13/25 (52%) treated by sequential estrogen and irradiation, and 8/17 patients (47%) with irradiation. It is also possible the improved survival in the estrogen responsive group was a direct result of improved local control. Persistent local disease can act as a source for distant metastases. Distant metastases was observed in 15% of patients when the primary tumor was controlled and 30% when there was persistent or recurrent local disease. Also, progressive local disease can be an important cause of death. This was most evident in our patients with estrogen refractory cancer. Almost all patients in this group had progressive local disease that caused serious urinary bleeding and urinary infection that were considered the major cause of death. Our results suggest bulky prostate cancer should be aggressively treated when first diagnosed. The value of adjunct estrogen is unproven. Our results with the use of estrogen prior to and concurrent with irradiation is encouraging. Estrogen may shrink the cancer and allow for a more favorable geometry for external irradiation. Tumor control and survival may be thereby improved.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of hypoxic hypoxia on systemic vasculature

Effects of hypoxic hypoxia (HH) on cardiac output (CO), CO distribution, arterial and venous pressure-flow curves, vascular compliance, vascular time constant (tau), and resistance to venous return (RVR) were evaluated on six dogs. The vascular bed was isolated into four compartments depending on venous drainage: superior vena cava (SVC), splanchnic, renal and adrenal, and the remainder of the inferior vena cava (IVC). Low arterial O2 content and PO2 produced a threefold increase in CO at the same mean arterial pressure and a significant redistribution of CO to the SVC. Arterial pressure-flow curves decreased their slope (i.e., flow resistance) by a factor of two in the IVC and renal beds and by a factor of three in the splanchnic and SVC beds. Venous pressure-flow curves for the animal also decreased their slope significantly. HH causes a twofold increase in venous compliance and in mean venous pressure; tau did not change, but RVR halved. Seventy percent of the CO increase is explained by the increase in mean venous pressure and 30% by the reduction in RVR.

Low electrocardiographic voltage in pericardial effusion

Although low ECG voltage has been associated with pericardial effusion, its diagnostic usefulness in such patients is unclear. When we examined the relationship between the volume of pericardial effusion and low voltage in 28 patients who underwent pericardial drainage, 14 patients exhibited low voltage (sum of limb lead QRS amplitudes of 30 mm or less). In eight patients, the QRS amplitude was 5 mm or less in each of the standard leads (absolute low voltage). There was no significant correlation between the volume of the effusion and the QRS amplitude (r = -0.30). This correlation did not improve (r = -0.37) when patients with left ventricular hypertrophy were excluded. Following pericardial drainage, the QRS amplitude increased in 21 of 24 patients and decreased in three. Low voltage persisted in nine patients; the pericardium was thickened in seven of the nine. Analysis of the sensitivity and specificity revealed acceptable sensitivity only with large effusions and no left ventricular hypertrophy. Absolute low voltage appeared to be specific in the diagnosis of moderate and large effusions among patients with pericardial effusion selected for this study.

Severe rectal injury following radiation for prostatic cancer

Between 1970 and 1981, 348 patients underwent definitive irradiation. Of these patients 6 (1.7 per cent) sustained severe rectal injury as manifest by major rectal bleeding, rectal stricture, rectal mucosal slough and rectal ulceration. Severe rectal injury was observed in 0 of 13 patients (0 per cent) treated with 125iodine, 3 of 329 (1 per cent) treated with 6,400 to 6,800 rad external irradiation, 2 of 39 (5 per cent) treated with 7,000 to 7,300 rad external irradiation, and 1 of 7 (14 per cent) treated with 198gold and external irradiation. The impact of radiation dose, radiation therapy technique and surgical trauma was assessed. Rectal injury was managed by supportive measures in 2 patients and by diverting colostomy in 3 with benefit. One patient underwent abdominoperineal resection. A small bowel fistula and an intra-abdominal abscess developed, and the patient died.

Preventive content of adult primary care: do generalists and subspecialists differ?

We compared preventive care performed by 20 generalists and 20 subspecialists practicing in Santa Clara and San Mateo Counties, California, by auditing charts of adult primary care patients for compliance with recommendations of the Canadian Task Force on the Periodic Health Examination. Generalists and subspecialists both provided 49 per cent of recommended preventive services. The two groups did not differ significantly in performance of any individual service. Performance varied widely within both groups. Of many factors explored, only two were associated with more preventive services: provision of a complete physical examination to the patient, and a physician's belief in the importance of a given service. The "generalist vs. subspecialist" debate assumes that a physician's specialty classification is an important predictor of behavior. For the performance of preventive care, this was not true in our study. Instead, physicians' beliefs and practice habits may be major determinants of the quality of preventive care provided. These exploratory findings needed confirmation in other settings.