Angiotensin II increases macrophage-mediated modification of low density lipoprotein via a lipoxygenase-dependent pathway

The molecular and cellular mechanisms by which hypertension enhances atherosclerosis are poorly understood. Angiotensin II (Ang II) has been implicated in the regulation of cellular lipoxygenases (LO), which are thought to play a role in atherogenesis by inducing oxidative modification of low density lipoprotein (LDL). We sought to test the hypothesis that Ang II would stimulate murine macrophage LO activity (which has both 12- and 15-LO activity). Competitive binding studies revealed the presence of Ang II AT1 receptors on mouse peritoneal macrophages (MPM) and J-774 cells, but not on the RAW cell line. Valsartan, a specific AT1 receptor antagonist inhibited Ang II binding, whereas PD 123319, an AT2 receptor antagonist did not. Incubation of MPM or J-774 cells with Ang II (10 pM to 1 microM) for 24 h led to a 2.5-3.5-fold increase in LO activity, measured as generated 13-HODE or 12(S)-HETE. This stimulation was inhibited by valsartan, but not by PD 123319. In contrast, Ang II did not stimulate LO activity in RAW macrophages. Semiquantitative reverse transcriptase-polymerase chain reaction showed a 2-3-fold increase in LO mRNA in MPM, but not in RAW cells after treatment with Ang II. Ang II also induced an increase in 12-LO protein. In addition, pretreatment of J-774 cells with Ang II increased in a dose-dependent manner the ability of the cells to modify LDL, resulting in greater chemotactic activity for monocytes, typical of minimally modified LDL. This stimulation was inhibited by AT1 receptor blockade. In summary, these data suggest that Ang II increases macrophage LO activity via AT1 receptor-mediated mechanisms and this further increases the ability of the cells to generate minimally oxidized LDL. These studies provide a link between hypertension and the associated increased atherosclerosis observed in hypertensive patients.

2-Cyclopropylindoloquinones and their analogues as bioreductively activated antitumor agents: structure-activity in vitro and efficacy in vivo

A series of 2-cycloalkyl- and 2-alkyl-3-(hydroxymethyl)-1-methylindoloquinones and corresponding carbamates have been synthesized and substituted in the 5-position with a variety of substituted and unsubstituted aziridines. Cytotoxicity against hypoxic cells in vitro was dependent upon the presence of a 5-aziridinyl or a substituted aziridinyl substituent for 3-hydroxymethyl analogues. The activity of 5-methoxy derivatives was dependent upon the presence of a 3-(carbamoyloxy)methyl substituent. Increasing the steric bulk at the 2-position reduced the compounds' effectiveness against hypoxic cells. A 2-cyclopropyl substituent was up to 2 orders of magnitude more effective than a 2-isopropyl substituent, suggesting possible radical ring-opening reactions contributing to toxicity. Nonfused 2-cyclopropylmitosenes were more effective than related fused cyclopropamitosenes reported previously. The reduction potentials of the quinone/semiquinone one-electron couples were in the range -286 to -380 mV. The semiquinone radicals reacted with oxygen with rate constants 2-8 x 10(8) dm3 mol-1 s-1. The involvement of the two-electron reduced hydroquinone in the mediation of cytotoxicity is implicated. The most effective compounds in vitro were the 2-cyclopropyl and 5-(2-methylaziridinyl) derivatives, and of these, 5-(aziridin-1-yl)-2-cyclopropyl-3-(hydroxymethyl)-1-methylindole-4 ,7-dione (21) and 3-(hydroxymethyl)-5-(2-methylaziridin-1-yl)-1,2-dimethylindole+ ++-4,7-dione (54) were evaluated in vivo. Both compounds showed antitumor activity both as single agents and in combination with radiation, with some substantial improvements over EO9 (3) at maximum tolerated doses and as single agents against the RIF-1 tumor model and comparable efficacy in the KHT tumor model.

Child protection or professional self-preservation by the baby nurses? Public health nurses and child protection in Ireland

An exploratory, focus group methodology was used to elicit the views of public health nurses (PHNs) on the topic of child welfare and protection in the context of new legislation and evolving child care policy in Ireland. The nurses' views were considerably at variance with the officially stated commitment to inter-disciplinary collaboration and coordination within the Community Care Programmes of Ireland's regional health boards. The PHNs feared that involvement in child care proceedings of a social control or adversarial nature would compromise them in terms of their traditional curative and preventive health roles, and, on this basis, argued that social workers should retain the bulk, if not all, of the responsibility for such child care activity. The nurses also defined their work roles in terms of their own traditional, professional commitment to individuals, families and communities, and felt less bound by or even aware of the corporate responsibility of their employing health board. It is concluded that the enactment of new legislation and allocation of additional resources do not resolve the issues of inter-disciplinary collaboration in this area.

Induction of common mucosal immunity by hormonally immunomodulated peripheral immunization

The study described in this report demonstrates that peripheral lymph nodes draining nonmucosal tissues can effectively serve as induction sites for the establishment of common mucosal immunity if the microenvironmental conditions are altered to mimic those normally present within mucosa-associated lymphoid tissues (e.g., Peyer's patches). Lymph node lymphocytes exposed in situ to the immunomodulatory influences of the hormone 1 alpha, 25-dihydroxy vitamin D 3 were found to produce less gamma interferon and interleukin-2 (IL-2) and far more IL-4, IL-5 and IL-10 than lymphocytes from control animals. When couples with vaccination with hepatitis B surface antigen (HBsAg), the hormone, immunomodulated switch from a peripheral lymph node phenotype to a Peyer's patch-like pattern promoted the induction of both a systemic and a common mucosal immune response. This was determined by the observed increased concentrations of serum anti-HBsAg antibody and by finding that anti-HBsAg secretory antibodies were detectable in urogenital, lachrymal, fecal and oral secretions only in the hormone-treated animals. In addition, specific antibody-secreting cells were detectable in the lamina propria of the lungs and small intestines of the hormone-treated animals subsequent to vaccination, indicating that the homing properties of antigen-specific B cells were being affected by the treatment procedure. The humoral and mucosal immune responses were further augmented if both 1 alpha, 25-dihydroxy vitamin D 3 and dehydroepiandrosterone were used together as hormonal immunomodulators. This novel immunization technique may afford new opportunities to effectively intervene in sexually transmitted diseases and other diseases caused by mucosal pathogens.

Court-ordered assessment: impact of maternal noncompliance in child maltreatment cases

Parental noncompliance to court orders is associated with several factors that jeopardize safe and stable child care. We advanced three hypotheses: (1) maternal noncompliance to court-ordered assessment is associated with loss of child custody; (2) noncompliance is related to court clinic custody recommendations; and (3) noncompliance is stable across child protection and court clinic settings. Based on a sample of 56 court-referred child maltreatment cases, all hypotheses were confirmed. Results are discussed in terms of: (a) maternal noncompliance as a marker for high-risk child care; (b) our limited understanding of the phenomenal meaning of noncompliance; and (c) the dearth of empirically derived intervention methods.

Temporal quantification of Alzheimer's disease severity: 'time index' model

A fundamental issue in the clinical and neuropathological assessment of Alzheimer's disease patients is quantification of dementia severity progression. Several methods have been advanced for the purpose of staging dementia with various sensitivities at different phases of the disease, but no mathematical function has been developed to link these measures to a physical continuum. Using a dynamic method for quantifying illness severity, change in severity over time was referenced to a cumulative temporal index, a physical dimension. Data from 33 patients with probable Alzheimer's disease with at least 2 successive assessments on three 50-point scales measuring cognitive, behavioral, and daily living skills were used to determine rate of change. 'Fuzzylogic' smoothing of the data, integration over time, and least-squares regression were used to derive a cubic polynomial function to calculate a severity measure in which 'days of illness' was estimated from the severity score. This method can be used to improve the comparability of performance across various mental status tests, and to link measures of very early phases of preclinical dementia and late profound dementia phases. This method also provides a description of an 'average' time course for any population from which the index is derived.

Physiological identification of the auditory nerve during surgery for acoustic neuroma

We report the design and clinical use of an electrode which can locate the acoustic nerve fibres in the normal eighth nerve and also in eighth nerves deformed by acoustic neuromas. The improvement in facial nerve preservation during acoustic neuroma surgery is partly due to the use of a facial nerve stimulator to anatomically locate the fibres. Our new acoustic nerve detector has the capability of anatomical location of cochlear fibres which may help to improve hearing preservation in selected cases of acoustic neuroma. The device functions by detecting the compound action potential evoked by no frequency auditory simulation at 500 Hz. The 500 Hz compound action potential is detected with a bipolar probe and then amplified and filtered. This results in a 500 Hz tone when the probe contacts the auditory nerve. Detection is virtually instantaneous. The acoustic nerve detector (AND) is demonstrated in a normal eighth nerve complex and its use is then described in the total removal of an acoustic neuroma with a 1 cm extracanalicular extension in which useful hearing was saved post-operatively. The present prototype may not be sensitive enough to detect the very low signals that may result when cochlear fibres are widely distorted around a large tumour or in cases where slight contusion of the nerve occurs during dissection. In all other cases the real time anatomical information is extremely helpful in guiding acoustic nerve dissection and also in monitoring the effects of petrous bone drilling.

Case reports and hypothesis: a neglect-like syndrome may be responsible for the motor disturbance in reflex sympathetic dystrophy (Complex Regional Pain Syndrome-1)

Reflex sympathetic dystrophy (RSD, Complex Regional Pain Syndrome-1, CRPS-1) is a chronic pain disorder associated with autonomic dysregulation that most commonly involves a limb. In addition to pain, motor dysfunction in the involved extremity may be a significant cause of disability. To spur reassessment of underlying mechanisms and development of novel rehabilitative approaches for RSD, we propose a new hypothesis: a neurologic neglect-like syndrome may explain the motor dysfunction that occurs in a subgroup of RSD patients. This hypothesis is based on a selected series of 11 patients who underwent specific neglect testing. The etiology of neglect in RSD is not clear, but we hypothesize that changes within central nervous system (CNS) structures may occur following persistent abnormal activation of the peripheral and autonomic nervous systems, which then may result in a neglect-like syndrome. Further study is needed to verify our clinical observations and test this hypothesis.

Child maltreatment: the collaboration of child welfare, mental health, and judicial system

The alliance of child welfare, mental health, and legal systems has received little empirical attention, despite the magnitude of its impact on children and families. We examined the congruence of child protection agencies legal positions, court clinic recommendations, and judicial dispositions in a sample of 59 contested child maltreatment cases. Placement recommendations/decisions among all three systems were highly correlated, although the relationship was not so strong as to undermine the independence of any one system. Where there was disagreement between successive evaluations, it was in the direction of enhancing family integrity and parental access rights. We advanced three hypotheses to account for our findings: (a) changes in successive recommendations reflect the increasing sophistication of the assessment process; (b) changes reflect increasing distance from the family's ecology and are therefore increasingly ill informed; and (c) the changes are purely probabilistic, reflecting a drift toward the societal status quo.

High frequency chest compression therapy: a case study

A new device, the ThAIRapy Bronchial Drainage System, enables patients with cystic fibrosis to self-administer the technique of high frequency chest compression (HFCC) to assist with mucociliary clearance. We review the literature on HFCC and outline a case study of a patient currently using the ThAIRapy Bronchial Drainage System. While mucociliary clearance and lung function may be enhanced by HFCC therapy, more research is needed to determine its efficacy, cost benefits, and optimum treatment guidelines. Although our initial experience with the patient using this device has been positive, we were unable to accurately evaluate the ThAIRapy Bronchial Drainage System.

Efficient translation of poly(A)-deficient mRNAs in Saccharomyces cerevisiae

The polyadenylate tail of eukaryotic mRNAs is thought to influence various metabolic phenomena including mRNA stability, translation initiation, and nucleo-cytoplasmic transport. We have analyzed the fate of mRNAs following inactivation of poly(A) polymerase in Saccharomyces cerevisiae containing a temperature-sensitive, lethal mutation (pap1-1) in the gene for poly(A) polymerase (PAP1). Inactivation of poly(A) polymerase (Pap1) by shifting cells to the nonpermissive temperature resulted in the loss of at least 80% of measurable poly(A) within 60 min. Northern blot analysis revealed the disappearance of some mRNAs (CYH2 and HIS4) consistent with a role for poly(A) tails in mRNA stability. However, other mRNAs (TCM1, PAB1, ACT1, and HTB2) accumulate as poly(A)-deficient (A < approximately 25) transcripts as defined by an inability to bind oligo(dT)-cellulose. Sucrose density gradient analysis of polyribosomes revealed a twofold reduction in the amount of each size class of polyribosomes in shifted cells and a commensurate increase in free ribosomes. However, poly(A)-deficient mRNAs in shifted cells remain associated with the same size polyribosomes as poly(A)+ mRNAs in unshifted cells, indicating normal initiation of translation. RNase mapping of transcripts from pap1-1 cells revealed PAB1 mRNA to be poly(A)- whereas TCM1 exists as equal amounts of poly(A)- and poly(A)+ mRNA 60 min after shift. Interestingly, both of these classes of TCM1 mRNA appear in similar amounts in each polyribosome fraction indicating that ribosomes may not distinguish between them. These findings suggest that under conditions of excess translational capacity, poly(A)- and poly(A)+ mRNAs may initiate translation with comparable efficiencies.

Evidence for altered alpha 2-adrenoceptor function following isolation-rearing in the rat

This study investigated central alpha 2-adrenoceptor function in differentially reared rats. Rats reared from weaning were either housed singly or in groups of five. Measurements of spontaneous ambulatory activity at 4 weeks postweaning showed that isolates were more hyperactive on exposure to a novel environment than grouped rats. alpha 2-Adrenoceptors were investigated using alpha 2-adrenoceptor agonist-induced behaviours, [3H]-idazoxan binding and measurement of forskolin-stimulated cyclic AMP accumulation. Clonidine (0.001-1.0 mg/kg IP) induced mydriasis in both groups with no difference observed in the response between the isolation and group-reared animals. Clonidine (0.01-0.5 mg/kg IP) induced hypoactivity in both groups, with the effect significantly greater in the isolation-reared rats. Idazoxan markedly attenuated both responses, confirming their induction by alpha 2-adrenoceptor stimulation. Clonidine-induced hypoactivity and mydriasis are mediated by pre- and postsynaptic alpha 2-adrenoceptors, respectively; therefore the results suggest rats reared in isolation have enhanced presynaptic but unchanged postsynaptic alpha 2-adrenoceptor function. Saturation binding experiments using [3H]-idazoxan were undertaken to determine alpha 2-adrenoceptor number (Bmax) and affinity (Kd) in membranes prepared from the frontal cortex and hippocampus. Analysis of binding data revealed an increase in receptor number in the hippocampus of isolates. Cyclic AMP accumulation was measured in hippocampal slices from differentially reared rats. Isolation-rearing did not affect cyclic AMP accumulation in response to stimulation by forskolin (30 microM). However, the selective alpha 2-adrenoceptor agonist, UK14304, produced a significantly greater inhibition of cyclic AMP accumulation in slices from isolated rats, confirming changes in alpha 2-adrenoceptor function following isolation rearing.

A profile of mood in ambulatory nursing home residents

This study examined mood in 54 ambulatory nursing home residents. Female subjects reported significantly lower scores on the Anger-Hostility subscale than either men or normative subjects. Women also scored lower than normative subjects on the Vigor-Activity and Confusion-Bewilderment subscales, whereas men scored lower on the Fatigue-Inertia subscale. Both men and women reported below norm scores for the Tension-Anxiety subscale. Further study is needed to identify sociological factors that may explain diminished expression of mood in this vulnerable population, and to compare these findings with the mood profile of community dwelling elders.

Chronic fatigue syndrome: a follow up study

Forty-six of 47 patients diagnosed as having chronic fatigue and offered treatment four years previously were followed up. Twenty-nine patients were interviewed, three patients refused an interview, and information on the remaining 14 was obtained from their general practitioners. All the instruments used at interview had been used in the initial study. The long-term prognosis for patients with chronic fatigue syndrome who have initially responded to treatment is good. Spontaneous recovery in those who declined or who did not benefit from treatment is unlikely. Patients who continue to fulfil the criteria for chronic fatigue syndrome four years after they were initially diagnosed are likely to have had more somatic disorders, to have been more fatigued, and to have had a previous psychiatric history when they were initially assessed.

Economics of health care reform

Several economic points require consideration when assessing the current cost of health care in the United States and the potential savings from proposed reforms. Most savings projections are based on assumptions and estimates that cannot be accurate under the best of circumstances, and the error in the final results is greatly compounded by even small errors in the initial estimates. Experience with health care programs worldwide, including our own Medicare program, has shown that final costs are usually much larger--often several times larger--than initial estimates. It is even more difficult to predict the behavior of the population under a system that does not yet exist, and it is not clear whether a system such as the Jackson Hole Plan will actually produce savings. The effect of our political system will have on any health system enacted through legislation must also be considered. The political process itself frequently results in more benefits rather than fewer, more regulation rather than less, and the shifting of costs to other sectors of the economy to minimize costs in the health sector. When presented with projections and predictions in health care planning, we must critically examine the initial assumptions, knowing that errors in these assumptions will magnify errors in the final results.

Randomized clinical trial of pressure-controlled inverse ratio ventilation and extracorporeal CO2 removal for adult respiratory distress syndrome

The impact of a new therapy that includes pressure-controlled inverse ratio ventilation followed by extracorporeal CO2 removal on the survival of patients with severe ARDS was evaluated in a randomized controlled clinical trial. Computerized protocols generated around-the-clock instructions for management of arterial oxygenation to assure equivalent intensity of care for patients randomized to the new therapy limb and those randomized to the control, mechanical ventilation limb. We randomized 40 patients with severe ARDS who met the ECMO entry criteria. The main outcome measure was survival at 30 days after randomization. Survival was not significantly different in the 19 mechanical ventilation (42%) and 21 new therapy (extracorporeal) (33%) patients (p = 0.8). All deaths occurred within 30 days of randomization. Overall patient survival was 38% (15 of 40) and was about four times that expected from historical data (p = 0.0002). Extracorporeal treatment group survival was not significantly different from other published survival rates after extracorporeal CO2 removal. Mechanical ventilation patient group survival was significantly higher than the 12% derived from published data (p = 0.0001). Protocols controlled care 86% of the time. Average PaO2 was 59 mm Hg in both treatment groups. Intensity of care required to maintain arterial oxygenation was similar in both groups (2.6 and 2.6 PEEP changes/day; 4.3 and 5.0 FIO2 changes/day). We conclude that there was no significant difference in survival between the mechanical ventilation and the extracorporeal CO2 removal groups. We do not recommend extracorporeal support as a therapy for ARDS. Extracorporeal support for ARDS should be restricted to controlled clinical trials.