Postoperative hypertension: a comparison of diltiazem, nifedipine, and nitroprusside

In previous studies, the treatment of postoperative hypertension with sodium nitroprusside induced ischemic metabolism without a decrease in coronary sinus blood flow. In contrast, the calcium antagonists diltiazem and nifedipine reduce blood pressure and may improve myocardial metabolism. A prospective randomized trial was performed in 62 patients, in whom hypertension developed (mean arterial pressure greater than 95 mm Hg) after coronary bypass procedures, to compare diltiazem (n = 22), nifedipine (n = 20), and nitroprusside (n = 20). All three agents reduced blood pressure equally (p less than 0.0001, by analysis of variance). Heart rate decreased with diltiazem (p = 0.006) but increased with nifedipine and nitroprusside (p less than 0.05). Left ventricular diastolic function (the relation between left atrial pressure and left ventricular end-diastolic volume) was not changed with the three drugs. Systolic function (the relation between systolic blood pressure and left ventricular end-systolic volume) was depressed with diltiazem (p = 0.05 by analysis of covariance) and nifedipine (p = 0.05) but not with nitroprusside. Myocardial performance (the relation between left ventricular stroke work index and end-diastolic volume) was depressed most by diltiazem (p = 0.001 by analysis of covariance), and to a lesser extent with nifedipine (p = 0.03), but not with nitroprusside. Myocardial lactate flux in response to the stress of atrial pacing decreased with nitroprusside but not with diltiazem or nifedipine (p = 0.03 by analysis of variance). Diltiazem and nifedipine are effective agents for treating postoperative hypertension after coronary artery bypass operations.

Waveguide Raman scattering for recovery of arbitrary thin-film concentration distributions

Quantitative Raman scattering measurements excited by the various eigenmodes of an optical waveguide were used to obtain depth profiles of poly(styrene-d(8)) (DPS) dispersed in poly(styrene) (PS) thin films without making any assumptions about the functional form of the spatial distribution of the deuterated material. The signal equations, which are ill-conditioned, were inverted to obtain the DPS distribution using a LaGrangian multiplier technique. Model calculations indicate that any arbitrary distribution can be profiled as long as the material can be prepared as an overlayer on an inert waveguiding substrate.

Methodologic considerations for investigating the diet-cancer link

Evidence from human ecological studies and experimental animal studies suggest that a number of dietary factors may have a role in the etiology of cancers of various sites. When associations are examined within populations on the level of the individual, they often weaken or disappear. Although in some cases the suspect nutrient may have no real carcinogenic effect, it is proposed that there are at least three important methodologic problems that could prevent the observation of a true association between dietary factors and human cancer. First, diet assessment methods are inadequate to estimate true exposure with sufficient accuracy and precision especially over long periods. Second, use of retrospective diet assessment methods in case-control study designs can often introduce an important bias. Third, sufficient within-study-group contrasts are often lacking. These problems are discussed in interpreting recent cancer studies of diet, and recommendations are made for future research.

Effects of anesthetic induction on myocardial function and metabolism: a comparison of fentanyl, sufentanil and alfentanil

Anaesthetic induction may induce myocardial ischaemia. A prospective randomized trial was instituted to compare the effect on ventricular function and myocardial metabolism of induction with fentanyl (FEN) or its analogues sufentanil (SUF) or alfentanil (ALF) in 96 patients undergoing elective coronary artery bypass grafting (CABG). Haemodynamic, metabolic (coronary sinus oxygen and lactate extraction) and gated ventriculographic measurements were made awake pre-induction (PRE), after induction (IND) and after intubation (INT). Induction was performed with FEN 75 micrograms.kg-1, SUF 15 micrograms.kg-1 or ALF 125 micrograms.kg-1 and metocurine. Fentanyl induction was associated with the greatest stability of mean arterial pressure (MAP), cardiac performance, and systolic function without associated myocardial lactate production. SUF produced the greatest depression of systolic function (p less than 0.05) but without haemodynamic instability or myocardial lactate production in all but one patient. Induction with ALF produced the greatest reduction in MAP (p less than 0.05) associated with the greatest decrease in diastolic compliance (p less than 0.05) and 50 per cent incidence of myocardial lactate production (p less than 0.05) with no significant change in coronary blood flow or myocardial oxygen consumption.

Major upper gastrointestinal tract bleeding. Relation to the use of aspirin and other nonnarcotic analgesics

In a hospital-based case-control study, the risk of a first episode of major upper gastrointestinal tract bleeding in subjects now known to be predisposed was assessed in relation to the use of nonnarcotic analgesics. For aspirin use within the week before the onset of symptoms, the rate ratio estimates, adjusted for potential confounding, were 15 (95% confidence interval, 6.4 to 34) for regular use (at least four days a week) and 5.6 (confidence interval, 2.7 to 12) for occasional use. For aspirin use discontinued at least one week earlier, the estimate was 1.6 (confidence interval, 0.6 to 4.2). There was no evidence that acetaminophen use increased the risk. For the regular use of other analgesics in the week before onset, the adjusted rate ratio estimate was 9.1 (confidence interval, 2.7 to 31); there were insufficient data to evaluate occasional use. The findings suggest that the risk of bleeding is increased substantially by aspirin, even when used occasionally. With the exception of acetaminophen, other nonnarcotic analgesics may also increase the risk, but they remain to be evaluated individually.

In vivo behavior of murine epidermal cell lines derived from initiated and noninitiated skin

The in vivo behavior of cell cultures derived from normal and carcinogen-treated mouse epidermis was studied by implanting the cultures in a s.c. vascularized bed protected by a silicone chamber. Cells derived from normal adult mouse epidermis as well as cells derived from tumor-promoter-treated skin were unable to grow in these systems. Conversely, cell lines derived from skin initiated with single doses of N-methyl-N'-nitro-N-nitrosoguanidine or 9,10-dimethyl-1,2-benzanthracene proliferated in these chambers, reforming an epithelial structure. The type of structure in the chambers varied, ranging from formation of almost normal epithelia to atypical invasive behavior. The variable in vivo behavior among the different cell lines may be attributed to the initiation agent, the number of passages of the cultures, random genetic events, the strain of mouse, or a combination of these factors. Most of the cell types used in this study and all the cell lines that were able to grow in these chambers were selected for resistance to Ca-induced terminal differentiation. However, resistance to terminal differentiation according to the Ca2+ switch does not always correlate with the ability to grow in the chambers, since cell lines derived from spontaneous foci of resistance failed to grow in this system. These studies showed some of the possibilities of the SC silicone chambers to study the histogenic potential of cell lines derived from carcinogen-treated epidermis. This system also appears suitable to study the complex relationship between epidermal cells and specialized (dermal) stroma.

Modified BFM therapy for children with previously untreated acute lymphoblastic leukemia and unfavorable prognostic features. Report of Children's Cancer Study Group Study CCG-193P

The Children's Cancer Study Group's (CCG) clinical trials in acute lymphoblastic leukemia (ALL) prior to 1981 consistently demonstrated that patients presenting with a white blood cell count (WBC) greater than or equal to 50,000/microliter or the "lymphoma syndrome" had a less than 40% 3-year event-free survival (EFS). The Berlin Frankfurt Munster (BFM) 76/79 study suggested that the prognosis of these patients could be improved. Before testing this therapy in a randomized setting, 29 CCG institutions used it for treatment of 209 newly diagnosed children with ALL and an initial WBC greater than or equal to 50,000/microliter or the lymphoma syndrome. In the intensive phases of therapy, 77% of cumulative parenteral doses and 55% of cumulative oral doses were within 10% of protocol requirements or were modified appropriately for reported toxicity. One hundred ninety-five patients achieved remission (93.3%). Eleven patients died in remission (5.6%)--10 during the intensive reinduction/reconsolidation phase. The 4-year EFS (+/- 1 SD) was 62% (+/- 3.7%) with a median follow-up of 40 months. Only one patient has had an isolated CNS relapse. These results appear superior to past CCG studies for high-risk patients and extend observations made from studies of similar therapy.

Acquired subglottic cysts in premature infants

Advances in the management of premature infants have resulted in improved survival. However, long-term intubation may produce associated laryngeal complications. We report 12 infants and children who developed subglottic cysts following long-term intubation as newborns. The majority of the cysts were in the posterior subglottic larynx. Laser excision of the cysts was undertaken in 8 patients and 3 underwent removal with cupped forceps. Recurrent cysts in 3 patients required more than one endoscopic procedure. The differential diagnosis of stridor in infants who have required long-term intubation includes subglottic cysts. The cysts are not always obvious at endoscopy and indeed may be buried below the mucosa within a soft tissue subglottic stenosis. Their presence may be suspected when tiny beads of mucus are released when laser surgery of a soft tissue stenosis is applied. Successful management of these cysts includes early precise diagnosis, with careful identification of these cysts to differentiate them from other types of subglottic stenosis. An initial attempt of conservative management with endoscopic excision is made. If this fails, an anterior cricoid split may be indicated in cases where the cysts are associated with soft tissue subglottic stenosis. Tracheostomy may be unavoidable in some cases.

Improved survival of infants less than 1 year of age with acute lymphoblastic leukemia treated with intensive multiagent chemotherapy

Infants with acute lymphoblastic leukemia (ALL) have a poor prognosis. Early disease recurrence, rather than excessive toxicity and complications resulting in limitation of therapy is the major factor responsible for this disappointing outcome. The CCG-192P trial was a groupwide pilot study of the Childrens Cancer Study Group for the treatment of ALL in patients at high risk for relapse, which was defined by wbc count greater than 50 X 10(3)/microliters at diagnosis. Because of the recognized poor prognosis, all infants less than 1 year of age were entered in this study regardless of wbc count at diagnosis. Therapy included intensive induction and consolidation followed by a cyclic, sequential maintenance program. The CNS prophylaxis consisted of intrathecal chemotherapy and cranial irradiation, which was deferred until patients were greater than 1 year of age. During the period January 1982 to January 1984, 27 infants ranging in age from 2 days to 11 months who had ALL were entered in this study; 71% had wbc counts greater than 50 X 10(3)/microliters, and 23% presented with CNS leukemia. Complete remission was achieved in 93% of the patients. The median duration of remission is 17 months. With a median follow-up of 43 months, the life-table estimate of event-free survival (EFS) is 36% at 4 years. A recently reported historical control group of infants with ALL who were treated with previous Childrens Cancer Study Group protocols demonstrated a median remission duration of 8 months and an estimated EFS of only 21% at 4 years. Toxicity and therapy-related complications were not observed more frequently in infants than in older patients treated with this protocol. However, EFS of infants was significantly worse than that of patients greater than 1 year of age (P = less than 0.001). All four CNS relapses occurred in patients who had received cranial irradiation. A wbc count less than 50 X 10(3)/microliters at diagnosis demonstrated significance (P = 0.03) as a favorable prognostic indicator in this small patient sample. Although these data are preliminary, they suggest that intensive therapy is reasonably well tolerated by infants and results in prolongation of remission duration and improved EFS.

Management of fibromyalgia, a distinct rheumatologic syndrome

The pathophysiology and management of fibromyalgia, a unique nonarticular rheumatologic syndrome characterized by diffuse musculoskeletal aches and pains, stiffness, discrete tender points at typical soft-tissue sites, and a characteristic sleep disturbance, are reviewed. The prevalence and incidence of fibromyalgia are not known, but it is one of the most common conditions seen by rheumatologists (after degenerative joint disease and rheumatoid arthritis). It was previously thought to involve inflammation of fibrous intermuscular septa and is sometimes referred to in the literature as fibrositis. It is not primarily psychogenic, but psychological factors may contribute. The tender points are the key to diagnosis. Fibromyalgia may be classed as primary (when no underlying disease is present) or secondary (when an associated condition exists). The pathophysiology of fibromyalgia is unknown but appears to involve complex interactions of central neurotransmitters with a relationship to pain perception, mood, and sleep. Treatment is empiric; nondrug treatment involving education, relaxation, and increased physical activity is essential. Few controlled trials of drug therapy have been conducted. Analgesics, anti-inflammatory drugs, phenothiazines, tricyclic antidepressants, and the tricyclic muscle relaxant cyclobenzaprine have been used; low doses of amitriptyline or cyclobenzaprine provide increased control of pain and mood.(ABSTRACT TRUNCATED AT 250 WORDS)

The measurement of performance in childhood cancer patients

The performance status of the child with cancer is an important outcome consideration in pediatric oncology research and practice. However, no single measure for children has been available. This is a report of the development and standardization of such a scale. The play-performance scale for children is a parent-rated instrument which records usual play activity as the index of performance. Performance status ratings were obtained on three groups of children: patients (n = 98), patients' siblings (n = 29), and an independent sample of hospital employees' children (n = 40). Children with all types and stages of childhood malignant neoplasms were represented. Test results established the parent as a competent, reliable rater and demonstrated the validity of the scale. Interrater reliability was examined using correlational statistics and percentage agreement. Agreement between parents was good, and there were no systematic rater biases. In addition, parents' ratings significantly discriminated differences in levels of functioning (mean score, patients 75.4 versus siblings 97.4). Correlational and analysis of variance (ANOVA) procedures demonstrated that the play-performance scale was significantly related to the global performance measures of experienced clinicians and was sensitive to change. Inpatients received a mean score of 42.3, outpatients 90.7, and normals 98.2. These findings indicate that the scale is both feasible and effective. It is concise, can be administered repeatedly even to extremely ill patients, and uses parents as observer reporters. The play-performance scale for children provides quantifiable, reproducible, and meaningful data, which is necessary for effective monitoring and management of the child with cancer.

Failure of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) to inhibit cell-cell coupling in newborn mouse epidermal cells and Chinese hamster V79 cells under non-standard culture conditions

The function of the skin tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate (TPA) during two-stage carcinogenesis in mice remains obscure because of TPA's numerous phenotypic effects. In vitro studies under established conditions have generated substantial interest in TPA's ability to inhibit, although transiently in some cases, direct cell-cell coupling in several permanent cell lines, by analogy allowing latent 'initiated cells' to escape homeostatic controls in vivo. Using different culture conditions designed to improve the growth of newborn mouse epidermal cells, we examined dye coupling in these cells, and metabolic co-operation in V79 cells, finding no effect of TPA on coupling. It appears that this effect of TPA is overly sensitive to in vitro conditions. Since a corresponding physiological effect has not yet been demonstrated in vivo, future studies should be directed to establish that coupling inhibition by TPA actually does occur and plays some role during tumor promotion in vivo, and is not merely a characteristic of certain culture systems.

Plasma hydroxychloroquine concentrations and efficacy in rheumatoid arthritis

Plasma levels of hydroxychloroquine (HCQ) and its metabolites were measured, by high performance liquid chromatography, in 37 rheumatoid arthritis patients who could be clearly distinguished as responders (n = 28) or nonresponders (n = 9) to HCQ, 400 mg/day. Efficacy in both groups was determined by the patients' erythrocyte sedimentation rates, joint counts, morning stiffness, global assessments, concurrent drug therapies, and grip strength. The response rate was 76%. Responders had a mean HCQ level of 213 ng/ml, versus 306 in nonresponders (P less than 0.05). The mean level of HCQ plus total metabolites in responders was 363 ng/ml, versus 554 in nonresponders (P less than 0.01). We conclude that monitoring plasma HCQ levels is unlikely to be helpful in individualizing effective drug dosage.

Terminal differentiation-resistant epidermal cells in mice undergoing two-stage carcinogenesis

We have used an in vivo-in vitro approach to investigate the cellular aspects of two-stage skin carcinogenesis. Female SENCAR mice initiated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were promoted twice weekly with 12-O-tetradecanoylphorbol-13-acetate (TPA). Epidermal cultures from untreated or TPA-treated mice had few focus-forming cells resistant to calcium-induced terminal differentiation. Cultures from mice treated with MNNG alone formed numerous foci. Brief promotion (four TPA treatments) of MNNG-treated mice produced fewer but statistically larger foci, suggesting that TPA was selecting against more slowly growing cells. MNNG plus TPA-treated mice with very early papillomas produced more and larger foci than those due to MNNG treatment alone, suggesting that the papillomas may have comprised calcium-resistant cells. These cells may indeed be initiated cells since a permanent cell line arising after MNNG plus brief TPA treatment eventually formed histological papillomas in vivo. If calcium-resistant cells are initiated, then there were many more initiated cells in the skin (with or without TPA treatment) than papillomas expected, implying that either some initiated cells never formed papillomas, or that a significant accumulation of initiated cells had already occurred in the skin within 2 weeks of MNNG treatment. Subsequent TPA promotion of these cells apparently produced a toxic response that passively selected for more rapidly growing initiated cells, which eventually accumulated into papillomas.

Epithelial ovarian cancer and coffee drinking

A recent report from a case-control study in Greece suggested that coffee consumption is related to an increase in the risk of ovarian cancer. This hypothesis was examined in a hospital-based case-control study in the US. Information on coffee drinking and other factors was obtained from 290 incident cases of epithelial ovarian cancer and compared with that of 580 controls with non-malignant conditions of acute onset and 476 controls with cancer of other sites. Adjustment was made for the potential confounding effects of several factors, including the major known risk factors for ovarian cancer. The estimated relative risk for drinking five or more cups of coffee per day, relative to none, was 1.1 (95% confidence interval, 0.6-2.0) using the controls with non-malignant conditions and 1.0 (0.5-1.8) using the controls with cancer. The estimates for drinking less than five cups per day were greater than 1.0, but this could have been due to chance. The consumption of decaffeinated coffee and tea also appeared to have no influence on risk. The evidence from this study suggests that, if coffee drinking increases the risk of ovarian cancer, the effect is small.

Risk factors for breast cancer in black women

Risk factors for breast cancer were examined in black women in a hospital-based case-control study of 529 black women with breast cancer and 589 controls. Late age at menarche was associated with a reduced risk of breast cancer. Women having 5 or more children had a reduced risk relative to that of women with fewer or no children. Late age at first birth was associated with an elevated risk of breast cancer. Among postmenopausal black women, obesity [as measured by body mass index (BMI)] was associated with an increased risk; among premenopausal women, there was no association of breast cancer with BMI. Women whose menopause occurred at or after age 50 were at increased risk relative to those whose menopause occurred earlier. There was no association between number of years of education and breast cancer in black women. History of benign breast disease and history of breast cancer in mother or sisters both were risk factors. The risk factor profile for breast cancer in black women was similar to that observed in whites.

The effect of cadmium pretreatment on the disposition and excretion of methylmercury and trace elements (zinc, copper) in rats

Cadmium chloride (Cd) was injected s.c. into male rats at a dose rate of 3 mg Cd/kg 3 times a week for 4 weeks. The animals were maintained for administration of methylmercury (203 Hg) chloride at a dose of 3 mg CH3Hg/kg given p.o. 3 times a week for 2 weeks, followed by 3 weeks of recovery period. Animals were sacrificed 24 h after the final dose of MeHg, or 5 weeks after cessation of Cd administration. Cd-pretreatment significantly decreased total Hg concentration in the kidney and RBC and almost completely inhibited demethylation of MeHg in the kidney (from 32% to 3% of inorganic Hg). Cd-pretreatment did not affect urinary excretion of total Hg, but significantly increased daily excretion of total Hg in feces. MeHg given alone significantly increased renal but not hepatic copper levels and decreased copper in the plasma and brain. In Cd-pretreated rats, both renal and hepatic copper concentration were in the normal ranges. Zinc levels in Cd-pretreated rats significantly increased in the kidney, liver and brain but decreased in plasma (compared to control and MeHg-alone treated animals). From these results it can be concluded that Cd-pretreatment may decrease MeHg toxicity by increasing the fecal mercury excretion and by inhibiting the formation of inorganic mercury in the kidney, which is a more potent renal toxin than MeHg.

Breast cancer risk in relation to early oral contraceptive use

It has been suggested that the risk of breast cancer is increased by oral contraceptive use before the first birth, or by use before age 25, particularly if certain formulations are used. These hypotheses were evaluated in a hospital-based case-control study. A total of 521 patients under age 45 with breast cancer were compared with 521 controls matched for age, time of interview, and geographic area. Oral contraceptive use before the first birth was reported by 155 patients and 137 controls. With allowance for confounding by multivariate analysis, the estimated relative risk was 1.0 (95% confidence interval, 0.6-1.5). The estimate was 1.0 (0.2-3.9) for any use among nulliparous women and 0.6 (0.3-1.3) for use before the first birth among parous women. Use before age 25 was reported by 145 patients and 141 controls, and the multivariate relative risk estimate was 1.0 (0.7-1.6); the results were similar when use of specific formulations was examined. For oral contraceptive use before either the first birth or age 25, the relative risk estimates were compatible with 1.0 for use of five or more years' duration or an interval since first use of at least 15 years. There was also no evidence of an increased risk in any subgroup including those at increased underlying risk because of factors such as a family history of breast cancer or a history of cystic breast disease. The findings suggest that, up to age 45, the risk of breast cancer is not influenced by the use of oral contraceptives before the first birth or before age 25 even if the use lasted for five or more years.

Influence of alloy composition on the hardening of silver-tin dental amalgam

The objective of the investigation was to examine the reactions of mercury with silver-tin alloys with compositions spanning the phase fields beta, (beta + gamma), gamma, and (gamma + Sn). The experimental methods employed include the application of light microscopy, scanning electron microscopy, and electron probe microanalysis. These techniques were used to investigate the mechanisms of reaction and to identify the nature and morphology of the reaction products formed on bulk specimens of the alloys. The progress and characteristics of the reactions that occur during hardening of amalgams prepared from powders of these alloys were monitored using a high-sensitivity dilatometer. These results were correlated with direct observations on the development of the microstructures. The reaction of mercury with the beta-phase alloy occurred rapidly and resulted in a very marked and rapid expansion during the initial stages of hardening. gamma-Phase alloys, on the other hand, reacted more slowly and contracted markedly during hardening. The behavior of amalgams made from alloys with compositions lying between these two extremes appeared to be explicable in terms of the characteristics of the separate phases from which they were constituted.

Bulk characterization and scanning electron microscopy of hydrogels of P(VA-co-NVP)

The bulk properties of uncrosslinked and crosslinked random copolymers of vinyl alcohol and N-vinyl-2-pyrrolidone [P(VA-co-NVP)] are reported. Analytical studies were performed by infrared and nuclear magnetic resonance spectroscopy, gel permeation chromatography, potentiometric titration, elemental analysis and scanning electron microscopy. The microscopic studies elucidated the effect of freeze-drying on the network surface topology. The results indicate macrosyneresis of the copolymer hydrogels upon freeze-drying even at -23 degrees C. Rapid collapse of the hydrogel structure is seen upon removal of the bulk and interfacial water in the frozen state.