Breast cancer diagnosis and prognosis in women following augmentation with silicone gel-filled prostheses

62 healthy women were studied mammographically before and after augmentation mammoplasty. Postaugmentation mammograms were done using both the implant compression and implant displacement technique. The amount of visualisable tissue was measured in all films before and after augmentation. We concluded: State-of-the-art film-screen mammography is extremely difficult to obtain in most patients augmented with silicone-gel-filled prostheses. On average, there is a decrease in measurable visualised breast tissue after augmentation mammoplasty with silicone-gel-filled prostheses. The area of mammographically measurable tissue is no different whether smooth or textured implants are used. Textured implants are less likely to form an early capsular contracture and are therefore preferred. However, the cancer-causing potential of polyurethane in humans is currently unknown. Anterior breast tissue is generally seen better with displacement mammography; posterior breast tissue with compression mammography. Better films are generally obtained when the implant is in the subpectoral position rather than subglandular. The more severe the capsular contracture, the poorer the mammogram. In addition 42 previously augmented patients developed breast carcinomas an average of 8.4 years after augmentation with silicone-gel-filled implants; 95% had palpable lesions (only 60% of which could be seen on mammography), 90% had infiltrating carcinomas, 45% had metastases to axillary nodes, and 7 patients have recurred, 5 of whom have died. We concluded: Augmented women who develop breast cancer are similar, in terms of tumour size and nodal positivity, to non-augmented breast cancer patients who present with palpable masses. When compared with non-augmented women whose breast cancers are found with screening mammography, augmented patients with breast cancer present with a higher percentage of invasive lesions and involved axillary lymph nodes, resulting in a poorer prognosis. The 40% false negative rate for mammography in this series is unduly high and alarming. Augmentation mammoplasty with silicone-gel-filled implants should be discouraged in women with a high risk of developing breast cancer.

Calcium antagonists and the kidney

Recently, attention has focused on the effects of calcium antagonists on renal function. When administered in vitro to the isolated perfused kidney, calcium antagonist exhibit consistent actions permitting characterization of their renal effects. Calcium antagonists do not affect the vasodilated isolated perfused kidney, but they do dramatically alter the response of the kidney to vasoconstrictor agents. In the presence of norepinephrine, calcium antagonists markedly augment glomerular filtration rate but produce only a modest improvement in renal perfusion. Utilizing the isolated perfused hydronephrotic rat kidney model that permits direct visualization of afferent and efferent arterioles, we have demonstrated that this preferential augmentation of glomerular filtration rate is primarily attributable to a selective vasodilation of pre-glomerular vessels. Although the clinical implications of such observations are not yet clear, preliminary studies in experimental animal models indicate that calcium antagonists may exert salutary effects on renal function in clinical settings that are characterized by impaired renal hemodynamics. The possible benefits of calcium antagonists in ameliorating the development of renal dysfunction in patients in whom there is increased risk for the development of acute renal insufficiency remain to be evaluated.

Voluntary exercise and experimental mammary cancer

The results of these studies indicate that voluntary activity suppresses the development of chemically and virally induced primary mammary tumors in rats and mice fed high-fat diets. These diets were chosen to mimic the current U.S. fat consumption of approximately 40% of calories as fat. It remains to be seen if activity exerts a similar suppressive effect on animals fed their customary low-fat diet (10% calories as fat). In general, the activity profiles of the female Fischer F-344 and Sprague-Dawley rat and the C3H/o mu j mouse exhibited a similar pattern with an early peak followed by a gradual plateau over time. The effects of activity on body fat composition showed a trend toward a decreased percent of body fat when compared to sedentary animals but a statistically significant decrease was found only in the F-344 female rat. In the DMBA model, carcinogen dose did alter outcome parameters. For example, time to first tumor was extended under low- but not high-DMBA conditions, and, conversely, tumor multiplicity was significantly decreased in the high- but not low-DMBA group. In the NMU model, an inverse association was found between the amount of activity and tumor incidence. A similar association was not found with the DMBA model. The reason for this is uncertain, but further analysis in terms of other parameters such as total tumor number may shed more light on this discrepancy. The suppressive effect of activity on the MMTV-induced mouse mammary tumor is of particular interest since it raises the possibility that activity may exert effects on the process of provirus insertion, and/or oncogene activation--an area of great potential promise in cancer prevention. Activity appeared to enhance the volume and to a lesser degree the number of metastatic foci in the lungs of F-344 retired breeders under high-fat but not medium-fat conditions. In addition, the most active animals in the high-fat group exhibited the greatest volume of metastases. These results, together with those in the NMU model, point to the critical importance of the quantity of voluntary activity an animal engages in and its relation to both primary and secondary cancer prevention. They imply that beyond a certain point of either frequency or intensity, the beneficial effect of exercise may be nullified by competing deleterious effects. The metastases study has also brought to light the importance of dietary fat as a potential intervening variable.(ABSTRACT TRUNCATED AT 400 WORDS)

Reduction of high-risk sexual behavior among heterosexuals undergoing HIV antibody testing: a randomized clinical trial

BACKGROUND

We evaluated the effect of HIV antibody testing on sexual behavior and communication with sexual partners about AIDS risk among heterosexual adults at a clinic for sexually transmitted diseases.

METHODS

We randomized 186 subjects to receive either AIDS education alone (the control group) or AIDS education, an HIV antibody test, and the test results (the intervention group). These subjects were then followed up 8 weeks later.

RESULTS

At follow-up, mean number of sexual partners decreased, but not differently between groups. However, compared with controls, HIV antibody test intervention subjects, all of whom tested negative, questioned their most recent sexual partner more about HIV antibody status (P less than 0.01), worried more about getting AIDS (P less than 0.03), and tended to use a condom more often with their last sexual partner (P = 0.05): 40% of intervention subjects vs 20% of controls used condoms, avoided genital intercourse, or knew their last partner had a negative HIV antibody test (P less than 0.005).

CONCLUSION

HIV antibody testing combined with AIDS education increases concern about HIV and, at least in the short term, may promote safer sexual behaviors. Additional strategies will be necessary if behaviors risky for HIV transmission are to be further reduced.

Right and left ventricular function after cardiac transplantation. Changes during and after rejection

BACKGROUND

Attempts to identify noninvasive markers of ventricular dysfunction accompanying acute rejection have been hampered by a lack of detailed simultaneous hemodynamic data. Therefore, we prospectively performed serial monitoring of detailed left and right heart hemodynamic parameters in cardiac transplant recipients at the time of routine endomyocardial biopsy to better define the physiology of the allograft heart during and after acute rejection.

METHODS AND RESULTS

To better assess the pathophysiology of the rejection process, 18 cardiac transplant patients were prospectively studied by serial right heart micromanometer catheterization and digital image processing at the time of routine endomyocardial biopsy. Eleven patients had 18 episodes of rejection. Studies of baseline (negative biopsy preceding rejection), rejection (acute moderate rejection), and resolved (first negative biopsy after rejection) states were compared. Seven patients who did not experience an episode of rejection served as the control group. Right ventricular minimum and end-diastolic pressures increased from baseline values of 0.9 +/- 3.2 and 6.9 +/- 3.7 mm Hg, respectively, to 3.2 +/- 5.5 and 9.9 +/- 6.6 mm Hg, respectively, with rejection (both variables, p less than 0.05) and remained elevated despite histological resolution of rejection (4.3 +/- 5.5 and 10.0 +/- 7.1 mm Hg, respectively; p less than 0.05 for both variables compared with baseline values). Concurrently, right ventricular end-diastolic volumes (133 +/- 29, 119 +/- 27, and 114 +/- 30 ml; baseline, rejection, and resolved, respectively) and left ventricular end-diastolic volumes (133 +/- 24, 117 +/- 20, and 113 +/- 30 ml; baseline, rejection, and resolved, respectively) significantly decreased during rejection and remained decreased after resolution of rejection (rejection and resolved compared with baseline values, p less than 0.05). Right ventricular chamber stiffness (0.055 +/- 0.035, 0.085 +/- 0.057, and 0.092 +/- 0.076 mm Hg/ml; baseline, rejection, and resolution, respectively; rejection and resolved compared with baseline values, p less than 0.05) increased with rejection and remained elevated after resolution of rejection. Right ventricular peak filling rate also increased from a baseline value of 2.48 +/- 0.45 to 2.76 +/- 0.63 ml end-diastolic volumes per second with rejection (p less than 0.05). Elevation of right ventricular filling pressures, peak filling rate, and chamber stiffness with a concomitant decrease in end-diastolic volume is consistent with a restrictive/constrictive physiology. Mean arterial blood pressure and systemic vascular resistance were elevated after the resolution of rejection (compared with either rejection or baseline values, p less than 0.05) associated with a higher mean daily dose of prednisone (resolved compared with either baseline or rejection values, p less than 0.05). The control group experienced a time-dependent increase in mean and diastolic systemic arterial pressures (both comparisons, p less than 0.05) without detectable diastolic dysfunction.

CONCLUSIONS

Persistence of biventricular diastolic dysfunction may be due to an irreversible effect of rejection, although multifactorial changes in left ventricular afterload occur that may complicate serial assessment of ventricular function.

Calcium antagonists and renal hemodynamics: implications for renal protection

Recently, attention has focussed on the effects of calcium antagonists on renal function. When administered in vitro to the isolated perfused kidney, calcium antagonists exhibit consistent actions permitting characterization of their renal hemodynamic effects. Calcium antagonists do not affect the vascular tone of the vasodilated isolated perfused kidney, but they do dramatically reverse the response of this preparation to vasoconstrictor agents. Studies using the isolated hydronephrotic rat kidney model, which permits direct visualization of afferent and efferent arterioles, have demonstrated that calcium antagonists selectively vasodilate preglomerular vessels. The clinical implications of such observations are still being delineated. Nevertheless, the results of preliminary studies in experimental animal models and in human transplant recipients suggest that calcium antagonists exert salutary effects on renal function in clinical settings characterized by impaired renal hemodynamics. Furthermore, a case can be made that these salutary renal hemodynamic effects of calcium antagonists commend their use in the management of essential hypertension.

Calcium antagonists and renal hemodynamics: implications for renal protection

During the past decade, attention has focused on the effects of calcium antagonists on renal function. When administered in vitro to the isolated perfused kidney, calcium antagonists exhibit consistent actions permitting characterization of their renal effects. Calcium antagonists do not affect the vasodilated isolated perfused kidney, but they do dramatically alter the response of this preparation to vasoconstrictor agents. Our recent studies with the isolated perfused hydronephrotic rat kidney model, which permits visualization of afferent and efferent arterioles, have demonstrated that the augmentation of glomerular filtration rate observed in the isolated perfused kidney is attributable to preferential vasodilation of preglomerular vessels. Although the clinical implications of such observations have not been fully delineated, the results of recent studies indicate that calcium antagonists exert salutary effects on renal function in patients with impaired renal hemodynamics. Such disorders include radiocontrast-induced nephrotoxicity and transplant-associated acute renal insufficiency. It is apparent, however, that the effects of calcium antagonists on renal blood flow commend their use in the management of essential hypertension.

Use of centrally acting sympatholytic agents in the management of hypertension

Considerable evidence suggests that hyperactivity of the sympathetic nervous system is implicated not only in the pathogenesis of essential hypertension but also in several blood pressure-independent complications of essential hypertension. Even with the advent of newer antihypertensive agents, including angiotensin-converting enzyme inhibitors and calcium antagonists, the centrally acting sympatholytics (alpha 2-adrenoceptor agonists) remain a valuable group of medications for the management of hypertension of all grades of severity. Their advantages include efficacy; rarity of contraindication; absence of most metabolic and serious side effects; favorable effects on systemic hemodynamics; lack of true tolerance and infrequency of volume expansion-related pseudotolerance; suitability in the elderly, in isolated systolic hypertension, and in patients with various concomitant conditions, such as diabetes mellitus; ability to reverse left ventricular hypertrophy; and relative low cost. The long duration of action of guanfacine hydrochloride, the most recently marketed agent, and of the transdermal formulation of clonidine is an especially commendable feature. The principal disadvantages of this class of medications are an overlap between the therapeutic dosage and that producing sedation and dry mouth and the potential to cause the discontinuation syndrome and sexual dysfunction.

Calcium antagonists and the kidney. Implications for renal protection

During the past decade, attention has been focused on the effects of calcium antagonists on renal function. When administered in vitro to the isolated perfused kidney (IPK), calcium antagonists exhibit consistent actions, permitting characterization of their renal effects. Calcium antagonists do not affect the vasodilated IPK, but do dramatically alter the hemodynamic response of the kidney to vasoconstrictor agents. Our recent studies using the isolated perfused hydronephrotic rat kidney model, which permits direct visualization of afferent and efferent arterioles, demonstrate that the preferential augmentation of glomerular filtration rate (GFR) observed in the IPK is attributable to preferential vasodilation of preglomerular vessels. Although the clinical implications of such observations have not been fully delineated, recent studies indicate that calcium antagonists exert salutary effects on renal function in clinical settings, characterized by impaired renal hemodynamics such as radiocontrast-induced nephrotoxicity and transplant-associated acute renal insufficiency. It is apparent, however, that the salutary effects of calcium antagonists on renal hemodynamics recommend their use in the management of essential hypertension.

Characterization of the renal microvascular effects of angiotensin II antagonist, DuP 753: studies in isolated perfused hydronephrotic kidneys

The renal microvascular effects of DuP 753, an orally active imidazole angiotensin II (ANG II) receptor antagonist were assessed directly in isolated perfused hydronephrotic rat kidneys. Unilateral hydronephrosis was induced to facilitate direct visualization of renal microvessels. Hydronephrotic kidneys were perfused in vitro and microvessel diameters were measured by automated computer-assisted image processing. The administration of 0.3 nmol/L ANG II decreased afferent arteriolar (AA) and efferent arteriolar (EA) diameters by 34 +/- 3% (from 17.9 +/- 0.6 to 11.9 +/- 0.6 microns, P less than .001, n = 11) and 28 +/- 3% (from 17.1 +/- 1.3 to 12.3 +/- 1.3 microns, P less than .001, n = 11), respectively. The subsequent administration of 0.1, 1.0, and 10 mumols/L DuP 753 reversed ANG II-induced vasoconstriction of the AA by 39 +/- 10%, 81 +/- 8%, and 103 +/- 9%, and of the EA by 22 +/- 7%, 51 +/- 6%, and 87 +/- 13%, respectively. These observations indicate that DuP 753 completely blocks both the renal afferent and efferent arteriolar actions of ANG II. In light of the pathogenetic role of ANG II in mediating the deranged renal hemodynamics associated with hypertension, congestive heart failure, and some forms of renal insufficiency, our findings provide a theoretical framework for future studies assessing the potential therapeutic applicability of DuP 753 in reversing ANG II-mediated renal vasoconstriction.

Cyclosporine-induced thrombotic microangiopathy resulting in renal allograft loss and its successful reuse: a report of two cases

Cyclosporine-induced thrombotic microangiopathy is a rare complication of renal transplantation. It commonly leads to graft loss. The mechanism of this entity is unknown. Factors intrinsic to the donor kidney appear to play an important role. We describe two cases of renal transplant patients who lost their first grafts secondary to cyclosporine-induced thrombotic microangiopathy. These patients were successfully retransplanted with an immunosuppressive protocol that included long-term cyclosporine. We conclude that graft loss from this entity is not a contraindication to subsequent successful transplantation with cyclosporine.

Increased release of the N-terminal and C-terminal portions of the atrial natriuretic factor prohormone during immersion-induced central hypervolemia in cirrhotic humans

The role of peptides from the N-terminus and C-terminus of the 126 amino acid (a.a.) atrial natriuretic factors (ANF) prohormone in modulating renal sodium and water handling in cirrhotic patients has not been defined. Eight cirrhotic individuals were evaluated; their mean basal circulating concentration of the C-terminus (a.a. 99-126; i.e., ANF) was 25 +/- 2 fmol/ml, not different from the 22 +/- 1 fmol/ml value found in 54 normal volunteers. On the other hand, the basal circulating concentrations of the whole N-terminus (a.a. 1-98) and the midportion of the N-terminus (namely a.a. 31-67; pro ANF 31-67) of the ANF prohormone in these cirrhotic subjects of 704 +/- 52 and 654 +/- 83 fmol/ml were significantly elevated (p less than 0.05; ANOVA) in comparison to control values (531 +/- 25, 317 +/- 22 fmol/ml, respectively). Following equilibration on a 10 mmol/day sodium diet, the responsiveness of the N-terminus and C-terminus of ANF prohormone to 3 h of water immersion, which induces marked acute central volume expansion, was evaluated in these 8 seated cirrhotic patients. There was a prompt increase in the circulating concentrations of immunoreactive (ir) pro ANF 1-98 (whole N-terminus), ir pro ANF 31-67, and ir ANF (C-terminus) within 15 min of immersion (p less than 0.05; ANOVA) compared to their preimmersion values. The response of circulating ir pro ANF 1-98, pro ANF 31-67, and ANF concentrations in these 8 cirrhotic subjects to immersion was significantly greater (p less than 0.05; ANOVA) than that of 7 healthy volunteers undergoing an identical 3-hour immersion study. With cessation of immersion, the C-terminus decreased within 30 min to a concentration not significantly different from preimmersion values, whereas the N-terminus and pro ANF 31-67 remained significantly elevated after 1 h.

Effects of calcium antagonists on renal hemodynamics

Recent attention has been focused on the effects of calcium antagonists on renal function. When administered in vitro to the isolated perfused kidney, calcium antagonists exhibit consistent actions permitting characterization of actions permitting characterization of their renal effects. Calcium antagonists do not affect the vasodilated isolated perfused kidney, but they do markedly alter the response of the kidney to vasoconstrictor agents. In the presence of norepinephrine, calcium antagonists markedly augment the glomerular filtration rate but produce only a modest improvement in renal perfusion. Studies using the isolated perfused hydronephrotic rat kidney model, which permits direct visualization of afferent and efferent arterioles, have demonstrated that the augmentation of the glomerular filtration rate is attributable to a preferential vasodilation of preglomerular vessels. Although the clinical implications of such observations are not fully delineated, preliminary studies in experimental animal models indicate that calcium antagonists might exert salutary effects on renal function in clinical settings characterized by an acute impairment of renal hemodynamics. It is apparent, however, that the renal hemodynamic effects of calcium antagonists commend their use in the management of essential hypertension.

Diclofenac induced immune thrombocytopenia

We describe a patient with scleroderma who developed immune thrombocytopenia secondary to diclofenac on 2 occasions. Platelet count returned to normal with cessation of diclofenac and institution of prednisone.

Renal microvascular actions of calcium antagonists

Calcium antagonists elicit vasodilation by altering the function of a specific class of potential-dependent calcium channels. These agents alter renal hemodynamics in a complex manner. Studies in the isolated perfused rat kidney demonstrate that the renal vasodilatory response to calcium antagonists varies depending on the nature of the underlying renal vasoconstriction. Thus, not all renal vasoconstrictor mechanisms are sensitive to calcium antagonists. Furthermore, in the presence of agonists such as norepinephrine or angiotensin II, calcium antagonists exert a greater effect on glomerular filtration rate than on renal perfusate flow. Direct observations of the renal microvasculature suggest that this preferential augmentation of glomerular filtration rate reflects the ability of calcium antagonists to dilate preglomerular vessels while preserving efferent arteriolar tone. Thus, under identical in vitro conditions, calcium antagonists reverse afferent (preglomerular) but not efferent (postglomerular) arteriolar vasoconstriction in isolated perfused hydronephrotic kidneys. Similarly, potassium (KCl)-induced depolarization, which directly activates potential-dependent calcium channels, preferentially constricts the afferent arteriole and produces a striking decrease in glomerular filtration rate and filtration fraction. Such observations indicate that differing activating mechanisms mediate vasoconstriction within the renal microcirculation and suggest that potential-dependent calcium channels prominently contribute to afferent, but not efferent, arteriolar vasoconstriction.

H(+)-induced vasodilation of rat aorta is mediated by alterations in intracellular calcium sequestration

Acidosis induces vasodilation both in vivo and in vitro. Although it is commonly surmised that acidosis alters contractility by affecting contractile proteins and calcium entry, the exact role of these mechanisms in acidosis-induced vasodilation has not been determined. In the present study, we demonstrated that a novel mechanism, involving increased calcium sequestration into intracellular sites sensitive to norepinephrine, mediates the vasodilation associated with relatively modest decreases in pH. The effects of changing pH from 7.4 to 7.0 on tension development, 45Ca fluxes, and the norepinephrine-releasable intracellular calcium stores were studied in isolated rat aorta. Acute acidification produced marked endothelium-independent dilations of aortic rings that had been precontracted with norepinephrine. In contrast, this maneuver had only modest effects on contractions elicited by 80 mM KCl or phorbol ester. Acidification in this range did not alter basal or norepinephrine-stimulated undirectional 45Ca influx, nor did it reduce the norepinephrine-induced net gain in 45Ca content. Furthermore, neither norepinephrine-stimulated 45Ca efflux nor the peak contractile response to norepinephrine in calcium-free buffer was affected, although in this setting, the duration of the phasic contractile response was shortened. When calcium was restored to tissues exposed to norepinephrine in calcium-free buffer, acidification slowed the rate of tension development without altering 45Ca uptake, thus changing the relation between tension development and calcium entry. These effects of acidification were shown to be associated with an increase in the amount of calcium sequestered into the norepinephrine-sensitive intracellular calcium store. These findings clearly indicate that acidification, within a range that has no effect on other aspects of smooth muscle activation, elicits vasodilation by stimulating intracellular calcium sequestration. This action may represent a predominant mechanism whereby acidosis alters vascular smooth muscle contractility.

Determinants of renal actions of atrial natriuretic peptide. Lack of effect of atrial natriuretic peptide on pressure-induced vasoconstriction

We have previously demonstrated that atrial natriuretic peptide (ANP) completely reverses norepinephrine-induced afferent arteriolar (AA) vasoconstriction. In the present study we characterized the effects of ANP on pressure-induced vasoconstriction of AA. Chronic unilateral hydronephrosis was induced to facilitate direct visualization of the renal microcirculation. Hydronephrotic kidneys were perfused in vitro, and AA diameters were measured during stepwise alterations in renal arterial pressure. Increasing renal arterial pressure from 80 to 180 mm Hg decreased AA diameter by 22 +/- 2% (from 18.5 +/- 1.0 to 14.4 +/- 1.0 microns, p less than 0.005). In the presence of 100 nM ANP [human ANP-(4-28)], AA vasoconstricted by 23 +/- 4%, indicating that ANP failed to modify the pressure-induced AA vasoconstriction. Furthermore, both nitroprusside (10 microM) and 8-bromoguanosine 3':5'-cyclic monophosphate (30 microM) only partially inhibited pressure-induced AA vasoconstriction (31 +/- 5% and 47 +/- 7%, respectively), whereas these vasodilators completely abolished norepinephrine-induced AA vasoconstriction. In contrast, nifedipine completely inhibited pressure-induced AA vasoconstriction. In summary, pressure-induced AA vasoconstriction is insensitive to the action of ANP, is relatively refractory to cyclic GMP-mediated vasorelaxation, but is completely inhibited by calcium channel blockade. Furthermore, since ANP completely abolishes norepinephrine-induced vasoconstriction but fails to affect pressure-induced vasoconstriction, it is apparent that the type of underlying vasoconstrictor stimuli constitutes a major determinant of the renal microvascular response to ANP.

[Right ventricular dysplasia]

Right ventricular dysplasia (RVD) is characterized by partial or total replacement of part of the right ventricular musculature by fatty and fibrous tissue. In its typical form it presents with ventricular tachycardia, usually in the fourth decade of life. 6 men and 2 women (mean age 55.6 years), referred for evaluation of arrhythmias or other cardiac symptoms, were diagnosed as having RVD on echocardiography after other causes of right ventricular enlargement were excluded. The mean age was 55.6 years, older than originally reported. 5 presented with supraventricular arrhythmias, including atrial flutter, atrial fibrillation, supraventricular tachycardia and sick-sinus syndrome. Only 2 had ventricular tachycardia; in 1 patient no arrhythmia was found. We conclude that RVD includes a wide spectrum of arrhythmias, of which ventricular tachycardia is probably not the most common. The incidence of RVD in the older population may be greater than originally reported, and may include a slowly developing form of the disease. In some cases RVD may be the pathophysiological basis of lone atrial fibrillation and sick-sinus syndrome.