Renal nitrate clearance in chronic kidney disease.

BACKGROUND: Nitric oxide (NO) is rapidly oxidised in humans to nitrite and nitrate, with nitrate being present in much greater abundance. These oxidation products can be recycled back into nitric oxide via a complex entero-salivary pathway, thus preserving NO activity. Approximately 65% of circulating nitrate is excreted in the urine in 48 h, with the excretory pathway of the remainder unknown. The effect of declining renal function on nitrate clearance is unknown METHODS: Forty five subjects, 21 M, 24F, median age 69 (range 27-75 years) with renal function assessed by CKD-EPI eGFR between 9 and 89 ml/min/1.73 m2 completed the study. Following a 24 h low nitrate diet a microplate spectrophotometric method was employed to measure plasma nitrate concentration and 24 h urinary nitrate excretion were measured to determine renal nitrate clearance. RESULTS: There was a strong positive correlation between urinary nitrate clearance and eGFR, (Spearman R = 0.7665, p < 0.0001) with a moderate negative correlation between plasma nitrate concentration and CKD-EPI eGFR, (Spearman's R = -0.37, p = 0.012). There was a trend between fractional excretion of nitrate and CKD-EPI eGFR (ml/min/1.73 m2) Spearman's R 0.27, p = 0.07 though this did not reach statistical significance. Plasma nitrate concentration and serum creatinine concentration were positively correlated, Spearman's R = 0.39, p = 0.008. CONCLUSIONS: We have observed a strong positive association between renal nitrate clearance and renal function such that plasma nitrate rises as renal function falls. Fractional excretion of nitrate appears to decline as renal function falls. As such, urinary nitrate excretion is unlikely to be a reliable marker of endogenous NO synthesis in settings where renal function is altered.

Bottleneck analysis approach to accelerate newborn care services in two regions in Ghana: implications for national newborn care.

OBJECTIVE: The aim of this work is to describe application of a data-driven approach (bottleneck analysis [BNA] approach process) to accelerate newborn care services in two regions and what effect it had on national-level newborn care interventions in Ghana. STUDY DESIGN: A mixed-method approach was used for the study. The BNA tool generated quantitative data and group discussions provided phenomenological explanations to identified service gaps. METHODS: Regional newborn care health service assessments were conducted in November 2013 through desk reviews, field and health facility visits and coaching/mentorship. The BNA tool (an excel-based tool) directly utilized service coverage data and programme monitoring and review reports in Ghana. Outputs were generated based on service coverage indicators: supply side/health system factors (commodities, human resource and access), demand side (service utilization) and quality/effective coverage. National targets were used as benchmarks to assess gaps in coverage indicators. RESULTS: Key health system bottlenecks included absence/stock-out of essential newborn care commodities/resuscitation kits and absence of updated policies at services delivery points. In both regions, less than 55% of health facilities had at least 80% of midwives trained to provide essential obstetric and newborn care, management of preterm babies, resuscitation and inpatient paediatric care. In addition, less than 35% of pregnant women were assisted by a skilled birth attendant (midwife) and monitored with a partograph in the two regions. Demand-side bottlenecks included cultural preference for home deliveries, limited knowledge on importance of postnatal care and poor community involvement.The BNA approach in the two regions resulted in the development of national and other regional operational plans and monitoring and evaluation framework for newborn care services in Ghana over the period 2012-2016, and a relative improvement in neonatal mortality at the regional and national level. CONCLUSION: The BNA tool and approach provided data-driven planning for newborn care service delivery in a low-income setting. It identified gaps in service coverage based on empirical data at lower levels of the health system and garnered strategies in addressing bottlenecks to newborn care services at the national level.

Types of female partners reported by black men who have sex with men and women (MSMW) and associations with intercourse frequency, unprotected sex and HIV and STI prevalence.

We used baseline data from a study of Black MSM/MSMW in 6 US cities to examine the association of female partnership types with disease prevalence and sexual behaviors among the 555 MSMW participants. MSMW reported more than three times as many total and unprotected sex acts with each primary as they did with each non-primary female partner. We compared MSMW whose recent female partners were: (1) all primary ("PF only", n = 156), (2) both primary and non-primary ("PF & NPF", n = 186), and (3) all non-primary ("NPF only", n = 213). HIV/STI prevalence did not differ significantly across groups but sexual behaviors did. The PF only group had the fewest male partners and was the most likely to have only primary male partners; the PF & NPF group was the most likely to have transgender partners. PF & NPF men reported the most sex acts (total and unprotected) with females; NPF only men reported the fewest. Implications for HIV risk and prevention are discussed.

'Information is information': a public perspective on incidental findings in clinical and research genome-based testing.

The potential for genomic incidental findings is increasing with the use of genome-based testing. At the same time approaches to clinical decision making are shifting to shared decision-making models involving both the healthcare community and the public. The public's voice has been nearly absent in discussions on managing incidental findings. We conducted nine focus groups and nine interviews (n = 63) with a broad cross-section of lay public groups to elucidate public viewpoints on incidental findings that could occur as a result of genome-based testing in clinical and research situations. Data were analyzed using qualitative content analysis. Participants wanted incidental findings disclosed to them whether or not these were clinical or research findings. Participants used different terms to define and describe incidental findings; they wanted to know that incidental findings are possible and be given a choice to learn about them. Personal utility was an important reason for disclosure, and participants believed that managing information is a shared responsibility between professionals and themselves. Broad public input is needed in order to understand and incorporate the public's perspective on management of incidental findings as disclosure guidelines, and policies are developed in clinical and research settings.

Primary Care 2030: Creating an Enabling Ecosystem for Disruptive Primary Care Models to Achieve Universal Health Coverage in Low- and Middle-Income Countries.

Background: Forty years after Alma Ata, there is renewed commitment to strengthen primary health care as a foundation for achieving universal health coverage, but there is limited consensus on how to build strong primary health care systems to achieve these goals. Methods: We convened a diverse group of global stakeholders for a high-level dialogue on how to create an enabling ecosystem for disruptive primary care innovation. We focused our discussion on four themes: workforce innovation and strengthening; impactful use of data and technology; private sector engagement; and innovative financing mechanisms. Findings: Here, we present a summary of our convening's proceedings, with specific recommendations for strengthening primary health care systems within each of these four domains. Conclusions: In the wake of the Astana Declaration, there is global consensus that high-quality primary health care must be the foundation for universal health coverage. Significant disruptive innovation will be required to realize this goal. We offer our recommendations to the global community to catalyze further discourse and inform policy-making and program development on the path to Health for All by 2030.

Effects of psychosocial stress on endothelium-mediated dilation of atherosclerotic arteries in cynomolgus monkeys.

The objectives of this study were to determine if psychosocial stress impairs dilation through endothelium-derived relaxing factor (EDRF)-mediated mechanisms and if this effect is long lasting. Monkeys were fed an atherogenic diet for 36 mo while in one of three experimental conditions: (a) stable social groups ("unstressed," n = 6); (b) unstable social groups for the first half of the experiment and stable groups for the second half ("early stress," n = 8); and (c) stable groups for the first half of the experiment and unstable groups for the second half ("late stress," n = 6). Iliac arteries were studied in organ chambers containing Krebs' buffer and 10(-6) M indomethacin. Arteries from the late stress group had impaired dilation (shift of the dose-response curve down and to the right) to acetylcholine and the calcium ionophore A23187 (for both, P < 0.05), but not to nitroprusside (P > 0.05), compared with unstressed or early stress monkeys. NG-methyl-L-arginine reduced the dose-response curve to both acetylcholine and A23187 in the unstressed group and resulted in similar vascular responses among all three groups (P > 0.05). We conclude that current, but not previous, exposure to chronic stress impairs endothelium-mediated dilation of atherosclerotic iliac arteries of cynomolgus monkeys through an EDRF-mediated mechanism.

Regional disparities in immunization services in Ghana through a bottleneck analysis approach: implications for sustaining national gains in immunization.

BACKGROUND: Immunization is considered one of the most cost effective public health interventions for reducing child morbidity, mortality and disability. The aim of this work is to describe the application of the Bottleneck analysis (BNA) process to assess gaps in immunization services in Ghana and implications for sustaining the gains in Immunization coverage. METHODS: A national assessment was conducted in May 2015, through use of desk reviews, field visits and key informant interviews. Quantitative data were analysed with the BNA Tool (an excel-based tool) based directly on service coverage data and programme monitoring and review reports in Ghana. Outputs were generated based on service coverage indicators; supply side/health system factors (commodities, human resource and access), demand side (service utilisation) and quality/effective coverage. National targets were used as benchmarks to assess gaps in coverage indicators. RESULTS: In all, only 50% of regions and districts had health facilities with at least 80% of health care workers training provided in-service training on routine immunization; only 40% of district had communities with functional fixed or outreach EPI service delivery point and over 70% of regions and districts had challenges with effective coverage of infants aged 0-11 months fully immunized during the past year. Other key health system bottlenecks included, limited number of fixed and outreach sites, difficult to reach island communities along the Volta Basin, inadequate storage facilities for vaccines at lower levels, stock out of vaccines and auto destruct syringes and absence of updated policies/field guides at services delivery points/facilities. In addition, inadequate in-service training in routine Immunization and absence of good quality data were major challenges. Demand side bottlenecks included fear of mothers on the safety of multiple vaccines and limited active involvement of communities in Immunization service delivery. CONCLUSION: The BNA tool and approach provided data driven planning of health service in Ghana. This resulted in the development of regional and national operational plans for immunization and will be the baseline for evaluating the national programme in three years.

Craniosynostosis and Resynostosis: Models, Imaging, and Dental Implications.

Craniosynostosis occurs in approximately 1 in 2,000 children and results from the premature fusion of ≥1 cranial sutures. If left untreated, craniosynostosis can cause numerous complications as related to an increase in intracranial pressure or as a direct result from cranial deformities, or both. More than 100 known mutations may cause syndromic craniosynostosis, but the majority of cases are nonsyndromic, occurring as isolated defects. Most cases of craniosynostosis require complex cranial vault reconstruction that is associated with a high risk of morbidity. While the first operation typically has few complications, bone rapidly regrows in up to 40% of children who undergo it. This resynostosis typically requires additional surgical intervention, which can be associated with a high incidence of life-threatening complications. This article reviews work related to the dental and maxillofacial implications of craniosynostosis and discusses clinically relevant animal models related to craniosynostosis and resynostosis. In addition, information is provided on the imaging modalities used to study cranial defects in animals and humans.

Short-term administration of estrogen and vascular responses of atherosclerotic coronary arteries.

OBJECTIVES: This experiment sought to determine the effect of short-term administration of estrogen on endothelium-dependent dilation in the coronary arteries of 13 surgically postmenopausal female cynomolgus monkeys. BACKGROUND: Long-term estrogen replacement therapy prevents impaired endothelium-dependent dilation of atherosclerotic coronary arteries in postmenopausal female monkeys. However, it remains unclear whether this action of estrogen is due to long-term effects on plasma lipids and atherogenesis or to direct short-term effects on the endothelium. METHODS: The monkeys consumed an atherogenic diet for 18 months after bilateral ovariectomy. Vascular responses were measured just before euthanasia and necropsy. Dextrose in water (control), acetylcholine, 10(-6)M, and nitroglycerin were infused for 2.5 min each both before and 20 min after intravenous injection of 54 ng ethinyl estradiol. RESULTS: Quantitative coronary angiography revealed that the arteries constricted (-17 +/- 3%) in response to intracoronary infusion of acetylcholine before estrogen treatment but dilated (+5 +/- 3%) 20 min after intravenous injection of ethinyl estradiol (p less than 0.05). Coronary arteries dilated in response to nitroglycerin both before and after administration of estrogen (p greater than 0.05). Vascular responses of coronary arteries, both before and after administration of estrogen, were not associated with variation in plasma lipid concentrations, blood pressure, heart rate or plaque size. CONCLUSIONS: Estrogen affects endothelium-dependent coronary dilation within 20 min of administration and may have rapid direct effects on the vascular endothelium.

Effects of hormone replacement therapy on reactivity of atherosclerotic coronary arteries in cynomolgus monkeys.

OBJECTIVES: We attempted to determine whether continuous and cyclic medroxyprogesterone acetate modulates the effects of estrogen on dilation of atherosclerotic coronary arteries in surgically postmenopausal female monkeys. BACKGROUND: Estrogen replacement in postmenopausal women preserves normal dilator responses of atherosclerotic coronary arteries. The effects of progestins on coronary artery reactivity have not been determined. METHODS: Repeated quantitative coronary angiography was used to study the effects after 1 month of 1) no hormone replacement (control) or oral administration of 2) continuous conjugated equine estrogens, 3) cyclic high dose medroxyprogesterone acetate (MPA) given on days 16 to 26 of the month, 4) conjugated equine estrogens plus continuous low dose MPA, or 5) conjugated equine estrogens plus cyclic high dose MPA on endothelium-mediated dilation of atherosclerotic coronary arteries in 12 cynomolgus monkeys. Change in diameter of the left circumflex coronary artery was measured in response to intracoronary infusions of acetylcholine (10(-6) mol/liter per min) and nitroglycerin (15 micrograms/min). RESULTS: Coronary arteries constricted during no hormone treatment (-8 +/- 3% [mean +/- SEM]), dilated during conjugated equine estrogen treatment (+3 +/- 1%, p < 0.05 vs. control) and constricted during cyclic MPA treatment (-3 +/- 2%). Addition of cyclic or continuous MPA to the conjugated equine estrogen regimen inhibited acetylcholine responses by 50% (p < 0.05 vs. conjugated equine estrogens). There was no effect of treatment on vascular response to nitroglycerin (p > 0.05). CONCLUSIONS: Treatment with conjugated equine estrogens, but not MPA, augmented endothelium-mediated dilation of atherosclerotic coronary arteries. Addition of cyclic or continuous MPA to the conjugated equine estrogen regimen diminished endothelium-mediated dilation.

Conjugated equine estrogens inhibit progression of atherosclerosis but have no effect on intimal hyperplasia or arterial remodeling induced by balloon catheter injury in monkeys.

OBJECTIVES: This study sought to determine the effects of estrogen treatment on atherosclerosis progression and the proliferative and structural responses of the atherosclerotic arteries to injury. BACKGROUND: Estrogen treatment suppresses the intimal response to arterial injury in nonatherosclerotic rodents and rabbits and inhibits the in vitro proliferation of smooth muscle cells. However, the effect of estrogen on the response of atherosclerotic arteries to transmural injury, as occurs in balloon catheter angioplasty in humans, is unknown. METHODS: Forty-six ovariectomized cynomolgus monkeys were fed an atherogenic diet for 30 months; 25 received 175 microg/day of conjugated equine estrogens, and 21 served as untreated control animals. All animals underwent balloon catheter injury of the left iliac artery. Subsets of animals underwent a necropsy study at 4, 7, 14 and 28 days after injury; injured and contralateral (uninjured) arteries were pressure-fixed and evaluated morphometrically. RESULTS: Estrogen treatment resulted in a 37% decrease (p < 0.05) in atherosclerosis (plaque area) in the uninjured artery. In response to injury, arterial cell proliferation increased at days 4 and 7, and intimal area was increased two- to threefold at day 28 (p < 0.05). Although estrogen treatment resulted in a trend toward decreased arterial cell proliferation at day 4, there was evidence of increased cell proliferation in both media and intima at day 7 (p < 0.05). However, there was no effect of estrogen treatment on intimal area or indexes of arterial remodeling in the injured artery at day 28 (p > 0.4). CONCLUSIONS. In contrast to previous studies of nonatherosclerotic animals, the results indicate that in the circumstance of transmural injury to arteries of primates with preexisting atherosclerosis, estrogen does not suppress arterial neointimal or structural responses to injury.

Pravastatin has cholesterol-lowering independent effects on the artery wall of atherosclerotic monkeys.

OBJECTIVES: This study examined the direct effects of pravastatin on the artery wall of atherosclerotic monkeys after dietary lipid lowering. BACKGROUND: Clinical trials suggest that hepatic hydroxymethylglutaryl coenzyme A reductase inhibitors may reduce the risk of coronary heart disease out of proportion to their effect on angiographically assessed lumen stenosis. METHODS: Thirty-two cynomolgus monkeys were fed an atherogenic diet for 2 years (progression phase) and then fed a lipid-lowering diet either containing (n = 14) or not containing (n = 18) pravastatin in the diet for an additional 2 years (treatment phase). As designed, total plasma cholesterol and high density lipoprotein concentrations did not differ between groups at the beginning of or during the treatment phase of the experiment (p > 0.05). RESULTS: Quantitative angiography revealed that coronary arteries of the pravastatin-treated monkeys dilated 10 +/- 3%, whereas those from untreated control monkeys constricted -2 +/- 2% in response to acetylcholine (p < 0.05). There were no treatment effects on plaque size of coronary arteries measured at the end of the treatment phase of the study (0.110 +/- 0.048 mm2 [untreated] vs. 0.125 +/- 0.051 mm2 [pravastatin]; p > 0.05) or on the amount of reduction in plaque size in common iliac arteries during the treatment phase of the study (48 +/- 5% [untreated] vs. 45 +/- 6% [pravastatin]; p > 0.05). However, histochemical analysis of the atherosclerotic lesions indicated that the arteries from pravastatin-treated monkeys had significantly fewer macrophages in the intima and media, less calcification and less neovascularization in the intima (p < 0.05). CONCLUSIONS: We conclude that compared with control monkeys, the arteries of pravastatin-treated monkeys had better dilator function and plaque characteristics more consistent with plaque stability than those of monkeys not receiving pravastatin. These beneficial arterial effects of pravastatin occurred independently of plasma lipoprotein concentrations and despite similar changes in plaque size between the groups.

Structure and function of vasa vasorum.

Vasa vasorum provide an important source of nutrition to arteries and veins. In normal arteries, vasa vasorum from the adventitia grow into the media of large arteries and veins and actively regulate blood flow to the wall of these vessels. In atherosclerotic arteries, vasa vasorum proliferate into the intima-media, where they provide nutrition to the thickened artery. These neovascular channels are thin-walled, however, and may contribute to intraplaque hemorrhage, plaque disruption, and mural thrombosis.

Prelabeled red nucleus and sensorimotor cortex neurons of the rat survive 10 and 20 weeks after spinal cord transection.

To demonstrate definitively the fate of the somata of rubrospinal and corticospinal neurons axotomized by a complete spinal cord transection at T-9, in young adult rats we prelabeled the neurons by injection into the lumbar enlargement of a retrogradely transported fluorescent dye, Fluoro-Gold, and four days later transected the cord. We found no loss in cell number ten or 20 weeks after axotomy. The average size of the neurons in each case is slightly but significantly reduced. These findings unequivocally demonstrate that the somata of long tract neurons of the rubrospinal and corticospinal systems persist in an atrophic and presumably inactive state for at least 20 weeks, and raise the possibility that treatment of spinal cord injury may normalize cell activity and allow long tract regeneration.

Insulin sensitivity and cardiovascular risk factors in ovariectomized monkeys with estradiol alone or combined with nomegestrol acetate.

We have previously shown that medroxyprogesterone acetate (MPA), either alone or combined with conjugated equine estrogens (CEE), significantly decreased insulin sensitivity (SI), compared with both untreated controls and those treated with CEE alone. The purpose of this study was to determine the effects of estradiol (E2), with and without nomegestrol acetate (NA; a potent progestin that lacks androgenic activity), on SI and arterial antioxidant activity, as determined by F2-isoprostanes. Thirty-six adult female cynomolgus monkeys (Macaca fascicularis) were ovariectomized and fed a moderately atherogenic diet, with one of the following three treatments added to the diet, for 12 weeks: 1) no treatment (control); 2) E2; or 3) continuous combined E2 + NA (E2+NA). SI and glucose effectiveness were assessed by the frequently sampled i.v. glucose tolerance test using a third-phase insulin infusion after 10 weeks of treatment. Cholesterol content and F2-isoprostanes were measured in the thoracic aorta after 12 weeks of treatment. E2 treatment resulted in a significantly greater SI, compared with control or E2+NA-treated monkeys (10.03 +/- 0.91 vs. 6.35 and 6.49 x 10(-4) min(-1) microU(-1) mL; P < 0.05). In contrast to our studies of CEE and MPA, E2+NA treatment, though reducing the SI below that of the E2 group, did not reduce the SI below that of control monkeys. As expected, the short period of treatment resulted in no significant differences in aortic cholesterol content. There was no treatment effect on total F2-isoprostanes (representing F2-isoprostane formation caused primarily by autooxidation), suggesting minimal antioxidant activity. However, there was a treatment difference in the prostaglandin F2alpha (PGF2alpha) isomer (a prostaglandin (PG) isomer formed by both autooxidation of arachidonate and cyclooxygenase activity). PGF2alpha concentrations were 32% lower with E2 treatment, compared with controls, and 36% lower, compared with E2+NA treatment (0.48 +/- 0.08 vs. 0.71 +/- 0.12 and 0.75 +/- 0.06; P < 0.05), suggesting differences in PG synthesis between hormone treatments. In conclusion, NA, a progestin without androgenic activity, may still affect some cardiovascular risk factors differently than estrogen-only therapy. However, it seems to be less detrimental than MPA.

Hypothesis: vasoconstriction contributes to amaurosis fugax.

Platelets play a critical role in the pathophysiology of amaurosis fugax. Emboli to retinal vessels apparently produce amaurosis but, in addition, we propose that augmented vasoconstrictor responses and vasospasm may contribute to amaurosis. In this study we tested the hypothesis that constrictor responses of retinal vessels to serotonin, which is released when platelets aggregate, are potentiated in experimental atherosclerosis. Blood flow to the retina was measured in normal and atherosclerotic cynomolgus monkeys. In normal monkeys, infusion of serotonin did not alter flow to the retina. In atherosclerotic monkeys, infusion of serotonin reduced retinal blood flow (in milliliters per minute per 100 g) from 66 +/- 7 (mean +/- SE) to 5 +/- 2. Infusion of serotonin in atherosclerotic monkeys abolished the retinal response to light. Thus, atherosclerosis greatly potentiates constrictor responses to serotonin in the retinal circulation and produces a profound but reversible impairment of retinal function. We propose that altered responses to vasoactive substances that are released by platelets may contribute to the pathogenesis of amaurosis fugax.

Effects of soy isoflavones on atherosclerosis: potential mechanisms.

It has long been recognized that coronary heart disease rates are lower in Japan, where soy consumption is common, than in Western countries. In experimental studies, atherosclerosis was reduced in animals fed diets containing soy protein compared with those fed diets with animal protein. Recently, several lines of evidence have suggested that the components of soy protein that lower lipid concentrations are extractable by alcohol (eg, the isoflavones genistein and daidzein). We recently evaluated the relative effect of the soy protein versus the alcohol-extractable components of soy on cardiovascular disease and its risk factors. Young male and female cynomolgus monkeys were fed diets that contained either 1) casein-lactalbumin as the source of protein (casein), 2) soy protein isolate from which the isoflavones were alcohol extracted (SPI-), or 3) isoflavone-intact soy protein (SPI+). The SPI+ group had significant improvements in LDL cholesterol and HDL cholesterol. Only HDL cholesterol was significantly improved in the SPI- group males compared with the casein group. The casein group had the most atherosclerosis, the SPI+ group had the least, and the SPI- group was intermediate but did not differ significantly from the casein group. Potential mechanisms by which soy isoflavones might prevent atherosclerosis include a beneficial effect on plasma lipid concentrations, antioxidant effects, antiproliferative and antimigratory effects on smooth muscle cells, effects on thrombus formation, and maintenance of normal vascular reactivity.

Vasa vasorum in the carotid sinus of atherosclerotic monkeys: implications for baroreceptor function.

The carotid sinus is unusually susceptible to development of severe atherosclerotic lesions. The purposes of this study were to examine effects of atherosclerosis on blood flow through vasa vasorum in the carotid sinus and to examine responses to humoral stimuli. Blood flow to vasa in the carotid sinus was measured with microspheres in 8 normal and 9 atherosclerotic cynomolgus monkeys. Blood flow to vasa in intima-media (in ml/min per 100 g) was 0.5 +/- 0.3 (mean +/- SE) in normal and 21 +/- 5 in atherosclerotic monkeys (P less than 0.05). Flow to adventitial vasa was 37 +/- 5 in normal monkeys and 50 +/- 7 in atherosclerotic monkeys (P greater than 0.05). Infusion of phenylephrine did not affect blood flow in normal or atherosclerotic monkeys. Infusion of serotonin did not affect blood flow to vasa in normal monkeys, but decreased flow to vasa in both intima-media and adventitia of atherosclerotic monkeys. In normal media, histological examination demonstrated the presence of a few vasa vasorum, which penetrated from adventitia. In atherosclerotic monkeys, medial vasa were much more frequent. Thus, (1) atherosclerosis produces marked increases in blood flow through vasa in intima-media of the carotid sinus, probably as a consequence of proliferation of vasa, and (2) in atherosclerotic monkeys, vasa constrict in response to serotonin. Based on these findings, we speculate that when serotonin is released as platelets aggregate at plaques in the carotid artery, serotonin may be delivered through vasa to nerves in the carotid sinus and thereby affect baroreceptor function.

Psychosocial impact of predictive testing for Huntington disease on support persons.

Although a support person is required by many centers during the predictive testing protocol for Huntington disease (HD), little is known about the psychosocial impact of predictive testing on persons serving in this role. Eighteen adults who were support persons during predictive HD testing in one HD testing center completed a semi-structured interview to describe their experiences. Participants also completed the Impact of Events Scale (IES) to assess perceptions of emotional distress regarding predictive testing and the State Anxiety Scale of the State Trait Anxiety Inventory (STAI) to assess anxiety regarding the interview. State anxiety scores were similar to normative values for working adults. Although support persons for individuals with a positive gene test scored higher on all measures of the IES than those who were support persons for persons with negative gene mutation results, these differences were not statistically significant. Support persons identified aspects of the protocol that did not fit their needs, perceived the testing process as extending into subsequent caregiving responsibilities when the test was positive, and were uninformed regarding specific caregiving issues for family members with the gene mutation. The impact of the testing experience appeared to be most intense for those support persons who were at-risk offspring of probands. Findings suggest that individual assessment of support person needs may allow more focused counseling of support persons during predictive genetic HD testing. Collaboration with health care providers may facilitate symptom management following testing.