Translational regulation of inhibin ßA by TGFß via the RNA-binding protein hnRNP E1 enhances the invasiveness of epithelial-to-mesenchymal transitioned cells.

The epithelial-to-mesenchymal transition (EMT) is a cellular process that functions during embryonic development and tissue regeneration, thought to be aberrantly activated in epithelial-derived cancer and has an important role in the process of metastasis. The transforming growth factor (TGF)-ß signaling pathway is a key inducer of EMT and we have elucidated a posttranscriptional mechanism by which TGFß modulates expression of select transcripts via the RNA-binding protein hnRNP E1 during EMT. One such transcript inhibin ßA is a member of the TGFß superfamily. Here, we show by polysome profiling that inhibin ßA is translationally regulated by TGFß via hnRNP E1. TGFß treatment or knockdown of hnRNP E1 relieves silencing of the inhibin ßA transcript, resulting in increased protein expression and secreted levels of the inhibin ßA homodimer, activin A. Our data indicate that the translational upregulation of inhibin ßA enhances the migration and invasion of cells that have undergone an EMT and promotes cancer progression in vivo.

Impact of different cell isolation techniques on lymphocyte viability and function.

The outcome of immunological assays is markedly influenced by the method of isolation of lymphocytes. It is, therefore, important to comparatively assess various techniques of isolation of lymphocytes, an aspect thus far not thoroughly addressed. In particular, the potential of isolation techniques to influence cell recovery, viability, and function has not yet been evaluated. These studies were designed to determine the effect of different mechanical tissue dissociation methods on the viability and function of lymphocytes. Following spleen and thymus removal, the lymphoid organs were dissociated by one of four different tissue dissociation techniques: metallic screen, sheer force slide, commercial stomacher, or plunger-screen. Cells were then enumerated and a trypan blue exclusion technique and 7-amino-actinomycin D (7-AAD) were both employed to assess viability. Mitogen-induced lymphocyte proliferation was measured using the Alamar Blue assay. Cell viability and lymphocyte surface antigen expression were assessed using flow cytometry. No significant differences in lymphocyte viability, morphology, or surface antigen expression were observed among the different techniques. Likewise, cellular apoptosis and necrosis were comparable across all the techniques. However, mitogen induced splenic T-cell proliferation was higher in cells collected using the metallic screen and plunger-screen isolation methods as compared to the sheer force slide or commercial stomacher procedures. These data suggest that cell recovery, morphology, and viability are not affected by isolation techniques. However, lymphocyte function, as assessed by mitogen induced proliferation, was negatively affected by the sheer force slide or commercial stomacher isolation techniques.

How do cancer patients who try to take control of their disease differ from those who do not?

The objective of this study was to compare patients who do and do not describe their coping strategies as attempts to control their cancer. This was a cross-sectional study of adult, oncology outpatients from an urban medical centre diagnosed 6-24 months previously. Using open-ended questions, we asked participants if they tried to 'control' their cancer or situation. If 'yes', how? If 'no', how had they 'dealt with' it? The Hospital Anxiety and Depression Scale (HAD) measured anxiety and depression. The Mental Adjustment to Cancer Scale (MAC) assessed six coping styles. Of the 44 participants, 57% were female. The mean age was 57 years. Eighteen (41%) said they used control strategies (control-yes), 11 (25%) said they did not (control-no), and 15 (34%) gave unclear responses (control-unclear). Participants cited 97 different coping strategies that were grouped into proactive (e.g. lifestyle changes) and reactive strategies (e.g. stoic behaviour). In comparing these groups, the control-yes group was more likely to be younger (P = 0.0001), live with other(s) (P = 0.003), be confident of being cured (P = 0.006), have greater 'fighting spirit' on the MAC (P = 0.04) and use more proactive strategies (P = 0.0001). The conclusion of this study is that cancer patients use many coping strategies, but those who think of them as methods of control are younger and more confident of being cured, and use more proactive strategies.

Extreme spore UV resistance of Bacillus pumilus isolates obtained from an ultraclean Spacecraft Assembly Facility.

Recent environmental microbial sampling of the ultraclean Spacecraft Assembly Facility at NASA Jet Propulsion Laboratory (JPL-SAF) identified spores of Bacillus pumilus as major culturable bacterial contaminants found on and around spacecraft. As part of an effort to assess the efficacy of various spacecraft sterilants, purified spores of 10 JPL-SAF B. pumilus isolates were subjected to 254-nm UV and their UV resistance was compared to spores of standard B. subtilis biodosimetry strains. Spores of six of the 10 JPL-SAF isolates were significantly more resistant to UV than the B. subtilis biodosimetry strain, and one of the JPL-SAF isolates, B. pumilus SAFR-032, exhibited the highest degree of spore UV resistance observed by any Bacillus spp. encountered to date.

Spherical grip strength in children 3 to 6 years of age.

OBJECTIVE: The purpose of this study was to establish normative data on spherical grip strength of children 3 to 6 years of age with the Martin Vigorimeter. METHOD: Two hundred twenty-five preschoolers in the Kalamazoo, Michigan, area were tested with standardized positioning and instructions. The mean of three trials for each hand was used as the grip-strength score. A repeated measure design was used and the right and left hands were alternated during testing to allow a 20-sec rest period between trials. Hand width also was measured in inches from the head of the second metacarpal to the head of the fifth metacarpal. RESULTS: Hand width and grip strength were significantly correlated for both the right (p < .0001) and the left hands (p < .001). Grip strength increased linearly across all of the age groups (p < .001). The results of paired t tests did not show a significant difference in grip strength between the right and left hands or between boys and girls. A table of mean grip-strength scores and hand width measurements along with their standard deviations is presented for clinical use. CONCLUSION: The vigorimeter could be used to assess the grip strength of children with rheumatic disorders without putting excessive pressure on the joints or skin of the hand.

Can we afford to do cardiac operations in 1996? A risk-reward curve for cardiac surgery.

Parsonnet risk estimates and postoperative lengths of stay were studied for two cohorts of cardiac surgical patients. The first cohort consisted of 287 patients and was taken from 1984, the first full year of this cardiac surgical program. The second cohort consisted of all 1,167 patients operated on in the calendar years 1989 to 1991. We found that the mean risk for the patients had nearly doubled in this interval and that the risk distribution changed significantly from one skewed toward good-risk patients to a nearly uniform distribution through all risk categories. A high correlation was identified (0.9761) between the postoperative length of stay and the mean risk estimates for the 1989 to 1991 cohort of patients. This permits a regression equation to be calculated showing that the length of stay could be estimated at 7.06 days + 0.21 times the mean risk for a patient or cohort of patients. This relationship is then used to develop a relationship between the net income for a given case or cohort of patients and the length of stay or risk. These data suggest that, in most hospitals, hospital fixed costs are a major determinant, even more so than daily charges, of the relationship between the hospital's finances and the mean risks of patients undertaken in the cardiac surgical program. The consequences of this are discussed.

Excitatory effects and electroencephalographic correlation of etomidate, thiopental, methohexital, and propofol.

Excitatory movements have been observed during induction of anesthesia with etomidate, thiopental, methohexital, and propofol. We studied the frequency of these excitatory effects and correlated movements with electroencephalographic (EEG) findings in 67 unpremedicated patients (mean age 66.1 yr, range 45-82 yr). Excitatory effects, including myoclonus, tremor, and dystonic posturing, occurred in 86.6% of patients receiving etomidate; 69.2% of the patient responses were myoclonic. Multiple spikes appeared on the EEG in 22.2% of the etomidate patients. The frequency of excitatory effects was 16.6% after thiopental, 12.5% after methohexital, and 5.5% after propofol. None of the patients receiving thiopental, methohexital, or propofol developed myoclonic or seizure activity. In most patients, the excitatory movements were coincident with the early slow phase of the EEG which corresponds to the beginning of deep anesthesia. We conclude that perhaps caution should be exercised when administering etomidate to patients with a history of seizures as the myoclonic activity is associated with seizure activity. The incidence of excitatory movements after administration of propofol is very low.

Copper thick film sintering studies in an environmental scanning electron microscope.

The significance of the ElectroScan environmental scanning electron microscope (ESEM) as a processing tool for studying dynamic morphological changes under controlled temperature/atmosphere conditions was evaluated. The ability to observe dynamic processes in situ, which cannot be achieved by other means, is critical to understanding microstructural formation. Processing of printed copper thick films on ceramics was used as a test case, wherein morphological changes associated with the steps of organic binder removal and sintering of copper particles were observed/examined in real time. Good agreement was seen between microstructures obtained in the ESM and those achieved in a belt furnace when similar process variables were used. When processed in atmospheres which were proven to induce sintering in a conventional belt furnace, sintering was evident in both cases, and the microstructural changes were documented on video-tapes in real time. Determination of critical event temperatures was achieved--that is, binder burnout occurring between 270 degrees and 350 degrees C, onset of oxidation at 520 degrees C, and sintering starting at 770 degrees C. It was thus verified that the microstructural changes during the copper thick film sintering process can be observed in situ using an ESEM.

Environmental scanning electron microscopy for dynamic corrosion studies of stainless steel piping used in UHP gas distribution systems.

An ElectroScan ESEM was used for in situ corrosion studies on cold drawn electropolished 316L stainless steel tube surfaces in the as-received and passivated conditions. Corrosion product was removed as it formed and the tube surface was viewed before, during, and after corrosive attack. The corrosion process was followed in situ, and the sample features most susceptible to corrosion (draw lines, inclusions, etc.) were identified. In addition, X-ray photoelectron spectroscopy (XPS) was used to study the changes in surface chemistry after corrosive attack. This information provided clear evidence of relevant corrosion mechanisms and relative corrosion susceptibility.

Phosphorylation of arabinosyl guanine by a mitochondrial enzyme of bovine liver.

Extracts of mitochondria isolated from bovine liver were shown to phosphorylate araG, forming araGMP as the sole product. When other nucleosides were used as competitors with araG as the substrate for phosphorylation, deoxycytidine, deoxythymidine and guanosine were not significantly inhibitory. However, the phosphorylation of araG was blocked by deoxyguanosine, deoxyadenosine and deoxyinosine. Deoxyguanosine was shown to be a competitive inhibitor of araG phosphorylation (apparent Ki for deoxyguanosine = 9 microM; apparent Km for araG = 66 microM). Likewise, araG was determined to be a competitive inhibitor of mitochondrial deoxyguanosine kinase activity (apparent Km for deoxyguanosine = 16 microM; apparent Ki for araG = 55 microM). These data suggest that the two nucleosides were phosphorylated by the same enzyme. Disc gel electrophoresis showed that the phosphorylating activity for araG migrated with deoxyguanosine kinase activity. The pH profiles of the araG and deoxyguanosine kinase activities were dissimilar. The optimum pH for deoxyguanosine kinase was 5.5; for araG kinase, it was 8.0. Collectively, these data suggest that araG is phosphorylated by mitochondrial deoxyguanosine kinase; however, separate forms of the enzyme or different reaction conditions may be involved in the optimal activities of the two catalytic events.

[Polyclonal B cell activation in infection caused by human immunodeficiency virus (HIV)]. / Activation polyclonale B associée à l'infection par le virus d'immunodéficience humaine (VIH).

87 patients with anti-HIV antibodies were divided into three groups based on the classification of the Centers for Disease Control and the following parameters reflecting polyclonal B cell activation were evaluated in these patients: immunoglobulin levels, circulating immune complexes and occurrence of autoantibodies. The results reported here indicate that intense polyclonal B cell activation occurs in both asymptomatic (CDC 2) and symptomatic patients (CDC 3 and CDC 4). Moreover, serological abnormalities were detected with similar frequency in the three groups studied.

B cell receptors for interleukin 2: demonstration of IL2 internalization and of complementary effects of lipopolysaccharide and phorbol diester on receptor expression.

We have previously shown (J. Exp. Med. 1984. 160: 1170) that murine B cells activated with lipopolysaccharide (LPS) and rabbit anti-mouse Ig antibodies together (LPS-RaMIg blasts) express high-affinity interleukin 2 receptors (IL 2R) and respond to IL 2. This is not the case for B cells activated with either LPS alone (LPS blasts) or anti-Ig alone. In the present study IL 2R function and expression were further investigated by using this model. First, it was found that LPS-RaMIg blasts internalize IL 2 in a time- and temperature-dependent manner very similar to that occurring in CTLL (T lineage) cells. LPS blasts, however, did not internalize IL 2. LPS blasts were found to express 12 times less binding sites for anti-IL 2R monoclonal antibody (PC 61 monovalent Fab) as compared to LPS-RaMIg blasts and at least 30 times less IL 2 binding sites of high as well as of lower affinity. Second, with regard to the requirements for receptor expression, it was observed that either anti-Ig or phorbol diester (phorbol-12-myristate 13-acetate) can induce IL 2R and IL 2 responsiveness (proliferation assay) in LPS blasts but not in fresh B cells. Taken together these results provide further evidence for the similarity of IL 2R function in activated B and T cells, confirm that surface-Ig cross-linkage and phorbol-12-myristate 13-acetate have similar effects on B cells and suggest that LPS on the one hand, and phorbol-12-myristate 13-acetate or anti-Ig on the other provide complementary signals necessary for IL 2R expression.

Renal handling of norepinephrine and epinephrine in the pig.

To investigate the renal handling of catecholamines in the pig, intravenous infusions of 51Cr-EDTA and PAH were performed in 7 animals, and samples for simultaneous measurement of norepinephrine (NE), epinephrine (E), 51Cr-EDTA and PAH were obtained through catheters placed into the aorta, left renal vein and both urethers. For both kidneys together, 51Cr-EDTA clearance [GFR] averaged 48 +/- 14 (+/- SD) ml/min (2.23 +/- 0.66 ml/kg/min). In the left kidney, GFR averaged 22 +/- 9 ml/min, arteriovenous PAH extraction 0.87 +/- 0.09, and calculated total renal plasma flow 91 +/- 30 ml/min. Plasma NE and E were lower in renal venous than arterial blood (P less than 0.005), extraction ratios averaging 0.36 and 0.77, respectively. NE excretion rate in final urine (8.9 +/- 4.3 ng/min) exceeded transrenal NE extraction rate (5.2 +/- 3.9 ng/min) by 3.7 +/- 4.4 ng/min. In contrast, urinary E excretion rate (2.9 +/- 2.0 ng/min) was slightly lower than transrenal E extraction rate (3.6 +/- 3.8 ng/min). These observations suggest that in pig kidneys, plasma PAH extraction rate and GFR related to body weight are quite similar to values in man. Three quarters of circulating E are extracted for the most part by tubular secretion, and the slightly smaller amount appearing in urine is consistent with some intrarenal metabolism. NE, presumably originating from intrarenal neuronal release and/or de novo production, is secreted into the urine.

Correction of cardiovascular hypersensitivity to norepinephrine by potassium supplementation in normotensive members of hypertensive families and patients with essential hypertension.

Blood pressure (BP), plasma levels of norepinephrine (NE) and epinephrine, the chronotropic effect of isoproterenol, and the relationship between variations in BP and concomitant plasma NE levels obtained during NE infusion were studied under control conditions and after 10 days of dietary potassium supplementation (100 mmol/day) in 12 normotensive subjects with negative family history (FH) of hypertension (mean BP 111/70 +/- 9/7 mmHg), 11 normotensive subjects with positive FH (112/73 +/- 8/6 mmHg), and 10 subjects with untreated borderline to mild essential hypertension (131/89 +/- 15/9 mmHg). Under control conditions, the increase in circulating NE required to elevate mean BP by 20 mmHg was significantly lower in hypertensive subjects (6.1 +/- 4.0 nmol/l) or normotensive subjects with positive FH (5.0 +/- 2.4 nmol/l) than in normal subjects with negative FH (9.9 +/- 6.4 nmol/l); the other study parameters were similar. After potassium supplementation, plasma and urinary potassium increased and body weight decreased slightly in all groups; basal plasma NE and epinephrine levels and cardiovascular effects of isoproterenol were unchanged. However, in normotensive subjects with positive FH and hypertensive subjects, the increase in plasma NE required to elevate mean BP by 20 mmHg was normalized (to 8.9 +/- 5.9 and 9.9 +/- 6.9 nmol/l, respectively), while BP tended to decrease slightly. These findings indicate that dietary potassium supplementation may favorably modify noradrenergic BP-regulation in hypertension prone individuals.

Relationship between plasma aldosterone and angiotensin II before and after noradrenergic inhibition in normal subjects and patients with mild essential hypertension.

The responsiveness of plasma aldosterone to the infusion of angiotensin II at dose rates of 2, 4, and 10 ng/kg X min was assessed in 11 normal subjects and 13 patients with mild essential hypertension before and after 4 weeks of treatment with the sympatholytic agent debrisoquine. Debrisoquine treatment caused a significant (P less than 0.01) decrease in circulating norepinephrine (-45%), but did not modify plasma levels of angiotensin II, renin, aldosterone, or epinephrine or the metabolism of sodium or potassium. In normal subjects, debrisoquine caused a significant shift to the left (P less than 0.05) of the correlation relating plasma aldosterone to plasma angiotensin II levels. In patients with essential hypertension, the aldosterone-angiotensin II interrelationship was not modified. These findings suggest that the sympathetic nervous system exerts an inhibitory influence on aldosterone responsiveness to angiotensin II in normal man, and that this physiological interaction is impaired in patients with essential hypertension.

Increased serum high-density lipoprotein cholesterol in hypertensive men treated with the potent vasodilator carprazidil.

The effects of the potent arteriolar vasodilator carprazidil on serum lipoproteins and various clinical, biochemical and endocrine parameters were assessed in 15 men with mild to moderate essential hypertension. Following a carprazidil monotherapy (average dose 50 to 60 mg/d) of 8 weeks (N = 15) or 16 weeks (N = 12) duration, blood pressure was decreased significantly (P less than 0.01), while serum high-density lipoprotein cholesterol (+ 26% and + 24%, respectively; P less than 0.01) and the alpha-lipoprotein fraction (+ 26% and + 41%) were increased. Low- and very low-density lipoprotein cholesterol, triglycerides, as well as mean body weight, blood and plasma volume, heart rate, and plasma renin, aldosterone, norepinephrine, and epinephrine were not consistently altered. These results indicate that treatment of hypertensive men with carprazidil in modest dosage may have a favorable influence both on blood pressure and serum lipoproteins.

Disturbed noradrenergic blood pressure control in normotensive members of hypertensive families.

The possible influence of a family history of hypertension on some variables of adrenergic blood pressure regulation was assessed. Blood pressure, heart rate, plasma renin activity, adrenaline and noradrenaline concentrations, and plasma or urinary electrolyte estimations did not differ significantly between two groups of normotensive subjects matched for age and sex with and without a family history of hypertension. Compared with subjects without a family history, however, an appreciably decreased pressor dose of infused noradrenaline, a distinct shift to the left in the relation between noradrenaline induced changes in mean arterial pressure and concomitant plasma noradrenaline concentrations, and an enhanced pressor response to given increases in plasma noradrenaline concentrations occurred in the group with a family history. These findings suggest that an imbalance between cardiovascular noradrenaline responsiveness and circulating noradrenaline is a common familial disturbance which could possibly predispose to the development of essential hypertension.

Studies on acute glucose-induced aldosterone suppression: role of renin-angiotensin system.

Glucose loading is known to cause acute suppression of plasma aldosterone and stimulation of plasma renin activity. The relative contribution of variations in circulating angiotensin II to the regulation of aldosterone secretion following glucose loading was assessed in ten normal subjects. The effects of a standard oral glucose loading test (100 g) on plasma concentrations of glucose, insulin, potassium, aldosterone, renin activity and cortisol were studied (a) under basal conditions, and (b) after inhibition of angiotensin II with the converting enzyme inhibitor captopril (50 mg t.i.d. during 3 days). Under basal conditions the acute increase in plasma glucose and insulin after glucose loading was accompanied by a significant decrease (P less than 0.01) in plasma cortisol and aldosterone and by a significant increase in plasma renin activity (P less than 0.01); plasma potassium was decreased slightly but not significantly. Following captopril treatment preloading plasma renin activity was increased significantly, most probably reflecting an effective reduction of angiotensin II. Glucose loading caused a similar suppression of plasma aldosterone, as observed under basal conditions. This observation suggests that renin activation does not substantially contribute to the acute regulation of plasma aldosterone after an oral glucose load.