bluuebunny/crossref_metadata_2025 huggingface dataset:
A modelling study of nitrogen deposited to arable land from the atmosphere and its contribution to nitrate leaching
Authors: Goulding K. W. T. , Bailey N. J. , Bradbury N. J.
Published: February 2007

Abstract. Atmospheric nitrogen (N) makes a significant contribution to the N inputs to agricultural systems and is a major eutrophying and acidifying input to natural and semi‐natural ecosystems. We have estimated the nitrogen deposited to arable land at Rothamsted and at two Nitrate Vulnerable Zones (NVZs) in the UK, Lichfield and the River Waveney. Using the SUNDIAL N cycle model calibrated against measured soil mineral N and leaching losses at Rothamsted, we have calculated the contribution of deposited N to nitrate leaching under a range of crops growing on the major soil series in the NVZs. Approximately 44, 46 and 28 kg N/ha per yr are deposited to arable land around Rothamsted and in the Lichfield and Waveney NVZs, respectively. Most of this is dry‐deposited in oxidized forms: nitrogen dioxide and nitric acid are the main components, arising mostly from industry, home heating and vehicle emissions. SUNDIAL predicts that current total leaching losses from arable crops average 39 kg N/ha per yr in the Lichfield NVZ anti 22 kg/ha per yr in the Waveney NVZ. Atsmospheric N contributes about 28% of the N leached from arable land in the Lichfield NVZ and 17% in the Waveney NVZ, a very significant amount. There is little variation in total leaching or the atmospheric contribution to it between soil series within each NVZ, but much variation with crop type and the weather: atmospheric N can comprise over 40% of the N leached under spring cereals in some years.
Soil erosion in Norway. An overview of measurements from soil loss plots
Authors: Lundekvam H. , Skoien S.
Published: February 2007

Abstract. Since 1980 soil erosion by water on agricultural areas has been measured in plot experiments conducted at the Department of Soil and Water Sciences at the Agricultural University of Norway. Meltwater in spring is the most serious erosive agent but rainfall on nearly saturated soil and hare soil also has a considerable erosive effect. Erosion as a result of heavy rainfall in the growing season occurs occasionally. A high proportion of water‐stable aggregates and a high content of clay and humus are characteristics of a soil with good resistance to emsion. Tillage has a strong influence on soil loss and it has been found that spring tillage reduces the annual soil loss by 90% compared with autumn ploughing.
Phosphorus losses from arable land in England
Authors: Catt J. A. , Howse K. R. , Farina R. , Brockie D. , Todd A. , Chambers B. J. , Hodgkinson R. , Harris G. L. , Quinton J. N.
Published: February 2007

Abstract. Concentrations and annual loadings of molyhdate reactive P (MRP) and total (including particulate) P (TP) are reported from field drainage, catchment and erosion experiments in England. Annual losses through field drains and in catchment runoff were 0.037‐0.74 kg MRP/ha and 0.37‐2.64 kg TP/ha, but those in surface runoff from experimental plots measuring erosion were generally much greater (often > 3 kg MRP/ha and up to 32 kg TP/ha in a wet year). Amounts of TP in drainflow and catchment runoff depended upon factors influencing soil dispersibility, such as particle size distribution and calcium carbonate content. The results to date suggest that P losses in surface runoff and erosion from arable fields to water are best limited by: (a) maximizing crop cover, using minimal cultivation practices and where possible planting crop rows across rather than up and down the slope, (b) avoiding cultivation practices that result in dispersion of soil particles, and (c) avoiding application of P fertilizer to wet soils when rainfall is likely soon after application. Consideration should he given to maintaining field drains below peak efficiency to reduce subsurface P losses.
High‐Density Lipoprotein Subclass Distribution in Individuals of Asian Indian Descent: The National Asian Indian Heart Disease Project
Authors: Superko H. Robert , Enas Enas A. , Kotha Purushotham , Bhat Naras K. , Garrett Brenda
Published: February 2007

Individuals of Asian Indian descent have significantly higher cardiovascular event rates as compared with other ethnic groups. The authors investigated the prevalence of metabolic disorders linked to coronary artery disease in an Asian Indian male population compared with non‐Asian Indian males. Standard lipid measurements did not discriminate between groups, and the Asian Indian group exhibited less of the high coronary artery disease risk small low‐density lipoprotein trait. Despite less of the small low‐density lipoprotein trait in the Asian Indian group and no difference in high‐density lipoprotein cholesterol, the Asian Indian group had a significantly higher prevalence (p <0.0002) of low high‐density lipoprotein 2b, implying impaired reverse cholesterol transport. This observation remained significant in the subgroup of patients with high‐density lipoprotein cholesterol over 40 mg/dL, a region felt not to reflect impaired reverse cholesterol transport. Low high‐density lipoprotein 2b combined with the higher lipoprotein(a) in the Asian Indian group may help explain the high prevalence of coronary artery disease in this ethnic population.
Knowledge of Cholesterol Levels and Targets in Patients With Coronary Artery Disease
Authors: Cheng Susan , Lichtman Judith H. , Amatruda Joan M. , Smith Grace L. , Mattera Jennifer A. , Roumanis Sarah A. , Krumholz Harlan M.
Published: February 2007

Little is known about the extent to which patients are aware of nationally‐recommended cholesterol and lipid subfraction targets. The authors interviewed 738 patients hospitalized with coronary artery disease to assess their knowledge of their low‐density lipoprotein, high‐density lipoprotein, and total cholesterol levels as well as corresponding national targets. Only 8%, 8%, and 43% of patients could recall their low‐density lipoprotein, high‐density lipoprotein, and total cholesterol values, respectively. Only 5%, 2%, and 50% could correctly name targets for these values. Knowledge of cholesterol targets was particularly poor among women, nonwhites, and patients without any college education. Patients with multiple cardiac risk factors and patients with a previous history of cardiovascular disease were no more knowledgeable about their cholesterol targets than those without these conditions. These findings suggest that current cholesterol education efforts appear inadequate, particularly for women, nonwhites, and patients without any college education.
Management Strategies for Patients With Hypertension and Diabetes: Why Combination Therapy Is Critical
Authors: Giunti Sara , Cooper Mark
Published: February 2007

Hypertension is commonly associated and acts synergistically with diabetes in increasing the risk of macrovascular and microvascular diabetic complications. Large‐scale clinical trials have demonstrated that this risk is significantly reduced by intensive antihypertensive treatment, and accordingly, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guideline has further lowered the blood pressure goals for diabetic subjects to <130/80 mm Hg. This implies that most diabetic patients will require the combination of two or more antihypertensive agents to achieve this blood pressure target. Although the most effective combination strategy in diabetes has not yet been determined in large‐scale randomized clinical trials, a combination that includes at least one agent that interrupts the renin‐angiotensin system appears to not only have a good safety profile, but may also provide additional renal and cardiovascular protection. Other antihypertensive agents should be added based on the patients risk profile and overall treatment regimen to achieve blood pressure goal.
Regression of Left Ventricular Hypertrophy in Diabetic Nephropathy: Loss of Parasympathetic Function Predicts Response to Treatment
Authors: Weinrauch Larry A. , Burger Andrew J. , Aronson Doron , Gleason Ray E. , Lee Annette T. , D'Elia John A.
Published: February 2007

Both left ventricular (LV) hypertrophy and decreased autonomic function are predictors of adverse cardiac events. Patients with diabetic nephropathy have an excess cardiovascular risk. The authors determined heart rate variability from 24‐hour ambulatory electrocardiographic recordings and measures of LV mass with systolic and diastolic function from echocardiograms. Patients with diabetic nephropathy (n=16) were seen weekly for insulin and hypertension management. Glycohemoglobin decreased from 9.5±0.4% to 8.3±0.4% (p=0.01), and advanced glycated end products decreased from 12.1 ±2.2 to 7.4±1.2 units (p=0.03). Mean arterial pressure and body weight did not change. Serum creatinine increased (1.8±0.1 mg/dL to 2.0±0.2 mg/dL; p=0.03). The authors used a panel of markers of baseline heart rate variation to assess autonomic function. When covariance of the heart rate interval results were evaluated, the group below the median was found to have a significant decrease in LV mass, from 230 g to 184 g (p=0.013); the group above the median had an increase (182 g to 193 g; p=0.5329). Baseline covariance of the heart rate interval predicted 12‐month changes in LV mass in 13 of 16 patients (predictive accuracy, 81 %). Improvement in measures of heart rate variation correlated with a decrease in LV mass. Parallel improvement of LV mass and autonomic function suggests a common mechanism, allowing for prediction of LV mass improvement through analysis of baseline heart rate variation.
Controlled‐Release Doxazosin as Combination Therapy in Hypertension: The GATES Study
Authors: Black Henry R. , Keck Michael , Meredith Peter , Bullen Kevin , Quinn Sheila , Koren Andrew
Published: February 2007

Doxazosin gastrointestinal therapeutic system (GITS) or placebo was added to the antihypertensive therapy of uncontrolled hypertensive patients in a prospective, randomized, double‐blind trial. Patients received doxazosin GITS 4 mg/d (n=89) or placebo (n=86) for 6 weeks in addition to entry antihypertensive medication. Doxazosin GITS was increased to 8 mg/d after 2 or 4 weeks if patients did not respond (sitting blood pressure <140/90 mm Hg and 10/10‐mm Hg decrease from baseline). Reductions from baseline in sitting and standing blood pressures were greater with doxazosin GITS than placebo at all time points (p≤0.017) except Week 1 sitting systolic pressure (p=0.068). The response rate was greater in the doxazosin GITS group (37.3%) than the placebo group (10.7%; p<0.001). With the exception of postural hypotension (7% compared with 0.0%), the frequency of adverse events was similar for doxazosin GITS and placebo. Doxazosin GITS was effective as combination antihypertensive therapy with the major classes of antihypertensive agents.
Antihypertensive Therapy and Its Effects on Potassium Homeostasis
Authors: Sica Domenic A.
Published: February 2007

The role of potassium in cardiovascular disease and the importance of preserving potassium balance have emerged as clinical hot points, particularly as they relate to cardioprotective and renoprotective therapies that secondarily promote potassium retention. Antihypertensive medications that most commonly influence serum potassium levels and/or total body potassium include β blockers and potassium‐wasting and potassium‐sparing diuretics as well as angiotensin‐converting enzyme inhibitors and angio‐tensin receptor blockers. Uncertainty exists as to the best way to monitor potassium levels when any of these drug therapies are used, particularly in the setting of chronic kidney disease and/or heart failure. Guidelines for the monitoring of serum potassium levels in the setting of antihypertensive therapy are at best makeshift and often drawn from the know‐how of the treating physician.
Hyperthyroidism: A Secondary Cause of Isolated Systolic Hypertension
Authors: Prisant L. Michael , Gujral Jaspal S. , Mulloy Anthony L.
Published: February 2007

Isolated systolic hypertension is the most common form of hypertension, especially among patients 50 years or older. What is not appreciated is that there are secondary causes of isolated systolic hypertension. Hyperthyroidism increases systolic blood pressure by decreasing systemic vascular resistance, increasing heart rate, and raising cardiac output. Potential cardiovascular consequences of hyperthyroidism include atrial arrhythmias (especially atrial fibrillation), pulmonary hypertension, left ventricular hypertrophy, and heart failure. The prevalence of hypertension is greater among hyperthyroid patients than euthyroid patients. Whether there is a blunted nocturnal decline in ambulatory blood pressure among hyperthyroid patients is more controversial. Treatment is associated with a reduction in systolic blood pressure, heart rate, and cardiac output.
Standardizing the Comparison of Systolic Blood Pressure vs. Pulse Pressure for Predicting Coronary Heart Disease
Authors: Davidson Karina W. , Haas Donald C. , Shimbo Daichi , Pickering Thomas G. , Jonas Bruce S.
Published: February 2007

Whether systolic blood pressure (SBP) or pulse pressure (PP) is more predictive of coronary heart disease remains controversial. The authors analyzed 6032 participants in the first National Health and Nutritional Examination Survey (NHANES I) followed up for an average of 16 years. Blood pressure was measured at baseline and coronary heart disease outcomes were determined from hospital or mortality records. Cox proportional hazard analyses were used to estimate the multivariate‐adjusted relative risk (RR) for increases of 10 mm Hg or 1 SD in SBP and PP, and the RR associated with PP was greater than the RR associated with SBP when using an increase of 10 mm Hg. However, when using an increase of 1 SD, the RR associated with SBP was larger than for PP. Although both are predictors, the authors conclude that SBP has a larger RR than PP for coronary heart disease events.
Association of a History of Systemic Hypertension With Mortality, Thrombotic, and Bleeding Complications Following Non‐ST‐Segment Elevation Acute Coronary Syndrome
Authors: Dumaine Raphaelle , Gibson C. Michael , Murphy Sabina A. , Southard Matthew , Ly Hung Q. , McCabe Carolyn H. , Giugliano Robert P. , Cannon Christopher P. , Antman Elliott M. , Braunwald Eugene
Published: February 2007

Chronic hypertension is a well established risk factor for the development of cardiovascular disease; however, its prognostic significance after a non‐ST‐segment elevation acute coronary syndrome remains to be established. Data from 15,414 patients included in six randomized Thrombolysis in Myocardial Infarction (TIMI) trials (TIMI 3B, TIMI11 A, TIMI 11B, TIMI 12, the Orbofiban in Patients With Unstable Coronary Syndromes [OPUS]‐TIMI 16, and the Treat Angina With Aggrastat and Determine Cost of Therapy With an Invasive or Conservative Strategy [TACTICS]‐TIMI 18) were analyzed. A history of hypertension was present in 10,998 (71.35%) patients; comorbidities and higher TIMI risk scores were more likely in these patients. However, positive troponin and ST‐segment deviations were less frequent among hypertensive patients. After multivariate analysis, the history of hypertension was associated with more adverse outcomes, specifically the composite end point of death/myocardial infarction at 30 days and 1 year (odds ratio [OR] 1.54, 95% confidence interval [CI] 1.31–1.81; p<0.001 at 1 year) than in patients without this history. An independent relationship was also observed with mortality (OR 1.70, 95% CI 1.34–2.16; p<0.001 at 1 year), myocardial infarction (OR 1.50, 95% CI 1.23–1.82; p<0.001 at 1 year), recurrent ischemia (OR 1.24, 95% CI 1.11–1.38; p<0.001 at 1 year), and major bleeding (OR 1.45, 95% CI 1.03–2.06; p=0.036 at 30 days). It was concluded that chronic hypertension remains an independent marker for major short‐ and long‐term cardiac adverse outcomes after non‐ST‐segment elevation acute coronary syndrome.
Antihypertensive Efficacy of Irbesartan/HCTZ in Men and Women With the Metabolic Syndrome and Type 2 Diabetes
Authors: Sowers James R. , Neutel Joel M. , Saunders Elijah , Bakris George L. , Cushman William C. , Ferdinand Keith C. , Ofili Elizabeth O. , Weber Michael A. ,   on behalf of the INCLUSIVE Investigators
Published: February 2007

This subgroup analysis of the Irbesartan/Hydrochlorothiazide (HCTZ) Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of irbesartan/HCTZ fixed combinations in adults with uncontrolled systolic blood pressure (SBP) (140–159 mm Hg; 130–159 mm Hg for type 2 diabetes mellitus [T2DM]) after ≥4 weeks of antihypertensive monotherapy. Treatment was sequential: placebo (4–5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and irbesartan/HCTZ 300/25 mg (8 weeks). In the intent‐to‐treat analysis, mean change from baseline (end of placebo phase) off all previous therapy to Week 18 (study end) in T2DM patients (n=227) was −18.2±14.1 mm Hg for SBP (primary end point; p<0.001) and −8.7±8.2 mm Hg for diastolic blood pressure (p<0.001). Mean SBP/diastolic blood pressure changes in patients with the metabolic syndrome (n=345) were –21.0±14.3/−10.4±8.5 mm Hg (p<0.001). Overall, 56% (95% confidence interval, 49%–62%) of T2DM and 73% (95% confidence interval, 68%–77%) of metabolic syndrome patients achieved SBP goal (<140 mm Hg; <130 mm Hg for T2DM). Goal attainment rates were significantly higher among women with the metabolic syndrome than men. Treatments appeared to be well tolerated. Irbesartan/HCTZ fixed combinations achieved SBP goals in over half of the T2DM patients and nearly three quarters of patients with the metabolic syndrome, with SBP uncontrolled on antihypertensive monotherapy.
Efficacy and Safety of Coadministered Amlodipine and Atorvastatin in Patients With Hypertension and Dyslipidemia: Results of the AVALON Trial
Authors: Messerli Franz H. , Bakris George L. , Ferrera R. David , Houston Mark C. , Petrella Robert J. , Flack John M. , Sun William , Lee EunMee , Neutel Joel M. ,   on behalf of the AVALON Investigators
Published: February 2007

The AVALON study was a randomized, multicenter trial to assess the efficacy and safety of coadministered amlodipine and atorvastatin in patients with hypertension and dyslipidemia. Phase one was an 8‐week, double‐blind, double‐dummy, placebo‐controlled period whereby patients received amlodipine 5 mg, atorvastatin 10 mg, amlodipine 5 mg and atorvastatin 10 mg, or placebo. Thereafter, all patients received single‐blind amlodipine 5 mg and atorvastatin 10 mg for 8‐weeks, followed by 12 weeks of open‐label treatment where doses could be titrated to improve low‐density lipoprotein cholesterol and blood pressure control. A total of 847 patients entered the double‐blind phase. At Week 8, 45% of the patients receiving amlodipine 5 mg and atorvastatin 10 mg reached both their blood pressure and low‐density lipoprotein cholesterol goals, compared with 8.3% with amlodipine (p<0.001), 28.6% with atorvastatin (p<0.001), and 3.5% with placebo. At 28 weeks, 67.1% of patients coadministered amlodipine and atorvastatin (mean doses, 7.6 mg and 28.4 mg, respectively) achieved both targets. Framingham estimated 10‐year risk of coronary heart disease declined from baseline levels of 15.1% to 6.9% at Week 28. Following coadministered treatment, the adverse events reported were similar to either agent alone. Concomitant administration of amlodipine and atorvastatin is an effective and well tolerated treatment for coexisting hypertension and dyslipidemia.
The transfusion of neutrophil‐specific antibodies causes leukopenia and a broad spectrum of pulmonary reactions
Authors: Fadeyi Emmanuel A. , De Los Angeles Muniz Maria , Wayne Alan S. , Klein Harvey G. , Leitman Susan F. , Stroncek David F.
Published: February 2007

BACKGROUND: Antibodies to neutrophil‐specific antigens are the best characterized cause of transfusion‐related acute lung injury (TRALI).

CASE REPORT: A double‐apheresis platelet (PLT) component was divided and transfused into two patients. One experienced chills, rigors, and dyspnea and the other experienced chills and headache. Transient leukopenia developed in both patients.

RESULTS: Evaluation of donor plasma revealed an anti‐HNA‐2a and no HLA Class I antibodies. The donor had donated 26 previous apheresis PLT components. The 27 donations resulted in 39 separate transfusions and 12 transfusion reactions in 9 patients. Five reactions occurred immediately after the transfusion, 10 within 1 hour, and all within 2.5 hours. Nine of the reactions involved symptoms or signs of pulmonary dysfunction. The symptoms were mild to moderate in nature. None of the inpatients required intensive care transfer nor did any outpatients require hospital admission. Recipient white blood cell (WBC) counts were measured within 8 hours after 38 of 39 transfusions. Leukopenia occurred in 9 of 12 (75%) transfusions with reactions and in 9 of 26 (35%) transfusions without. The reactions did not correlate with pretransfusion WBC count.

CONCLUSIONS: Neutrophil antibodies cause a wide variety of transfusion reactions that do not necessarily meet the definition of TRALI. Donors of blood products causing even mild pulmonary reactions or leukopenia should be tested for neutrophil‐specific antibodies.
Intracardiac Echo‐Guided Image Integration: Optimizing Strategies for Registration
Authors: FAHMY TAMER S. , MLCOCHOVA HANKA , WAZNI OUSSAMA M. , PATEL DIMPI , CIHAK ROBERT , KANJ MOHAMED , BEHEIRY SALWA , BURKHARDT J. DAVID , DRESING THOMAS , HAO STEVEN , TCHOU PATRICK , KAUTZNER JOSEF , SCHWEIKERT ROBERT A. , ARRUDA MAURICIO , SALIBA WALID , NATALE ANDREA
Published: February 2007

Introduction: Image integration is being used in ablation procedures. However, the success of this approach is dependent on the accuracy of the image integration process. This study aims to evaluate the in vivo accuracy and reliability of the integrated image.

Methods and Results: One hundred twenty‐four patients undergoing radiofrequency (RF) ablation catheter ablation for atrial fibrillation (AF) were recruited for this study from three different centers. Cardiac computerized tomography (CT) was performed in all patients and a 3D image of the left atrium (LA) and pulmonary veins (PVs) was extracted for registration after segmentation using a software program (CartoMerge, Biosense Webster, Inc.). Different landmarks were selected for registration and compared. Surface registration was then done and the impact on integration and the landmarks was evaluated.

The best landmark registration was achieved when the posterior points on the pulmonary veins were selected (5.6 ± 3.2). Landmarks taken on the anterior wall, left atrial appendage (LAA) or the coronary sinus (CS) resulted in a larger registration error (9.1 ± 2.5). The mean error for surface registration was 2.17 ± 1.65. However, surface registration resulted in shifting of the initially registered landmark points leading to a larger error (from 5.6 ± 3.2 to 9.2 ± 2.1; 95% CI 4.2–3.05).

Conclusion: Posterior wall landmarks at the PV‐LA junction are the most accurate landmarks for image integration in respect to the target ablation area. The concurrent use of the present surface registration algorithm may result in shifting of the initial landmarks with loss of their initial correlation with the area of interest.
Determination of Phenotype Associated SNPs in the MC1R Gene*
Authors: Branicki Wojciech , Brudnik Urszula , Kupiec Tomasz , Wolañska‐Nowak Paulina , Wojas‐Pelc Anna
Published: February 2007

ABSTRACT: Prediction of physical appearance based on genetic analysis is a very attractive prospect for forensic investigations. Recent studies have proved that there is a significant association between some genetic variants of the melanocortin 1 receptor (MC1R) gene and red hair color. The present study focuses on the potential forensic applicability of variation within this pigment‐related gene. Sequencing of the complete MC1R gene was performed on a group of red‐haired individuals and controls with different pigmentation. A major role in determination of red hair color is played by two MC1R variants—C451T and C478T. The optimized minisequencing assay for genotyping of the above positions and three other important red hair‐related MC1R polymorphisms, C252A, G425A, and G880C was successfully applied to analyze typical forensic specimens. Determination of a homozygous or heterozygous combination can be a good predictor of both red hair color and fair skin of a subject.
Legal systems, institutional environment, and food safety
Authors: Brewster Neşve A. Turan , Goldsmith Peter D.
Published: February 2007

In the aftermath of the recent food scares, the United States and the United Kingdom face major challenges to maintain a safe food system. Regulators on opposite sides of the Atlantic are facing rapid product and process innovations, changes in consumption behaviors, expansion of international trade, and discovery of new food hazards. The U.K. and the U.S. demonstrate different approaches to manage safety risks. This article will focus on two issues: the reasons behind the differences in the American and English policy approaches to food safety, and how these differences impact U.S. safety outcomes. A comparative legal framework is provided to understand how food safety is elicited in the economy and the incentive implications of the different institutional settings. These two different lenses, because they differ so, teach us about the fundamental sources of safety. The U.K.'s prevalent doctrine is parliamentary sovereignty and leads to a regulatory framework, while the U.S. is based on constitutional supremacy and relies on a legal framework. The source of safety under a regulatory framework is the government bureaucracy, while the U.S. legal framework provides an important point of departure—the constitutional standing of the firm and the consumer. We argue that while the U.K. system is structured to work through a regulatory framework to enhance the supply of safety in the economy, the U.S. system is much less directed. The legal system, the subject of this article, plays an important role not only in discouraging breach but also in acting as a check on the discretionary authority of the regulator. In the end, the U.S. and the U.K. may have equally safe food systems, but what differs is the fundamental source of the safety supply. The practical implication is that safety in the food system emerges from several sources, not just through regulation. Therefore, direct importation of U.K.‐style regulatory approaches may not be effective within a U.S. constitutional setting.
Why don't producers adopt best management practices? An analysis of the beef cattle industry
Authors: Gillespie Jeffrey , Kim Seon‐Ae , Paudel Krishna
Published: February 2007

Cattle producers were surveyed to determine their adoption rates and reasons for non‐adoption of 16 best management practices. Potential reasons for non‐adoption included unfamiliarity, non‐applicability, high cost, still considering adoption, and preference not to adopt. The two most commonly cited reasons for non‐adoption were unfamiliarity and non‐applicability of the practice. Results highlight the importance of educational efforts in encouraging adoption, as well as farm type and financial situation of the farmer.
Influence of the Pineal Gland and Circadian Rhythms in Circulating Levels of Thyroid Hormones of Male Hamsters
Authors: Vriend Jerry
Published: February 2007

Thyroxin (T4) and triiodothyronine (T3) were measured by radioimmunoassay in serum of hamsters sacrificed at 4‐hr intervals throughout the daily light‐dark cycle (14L/10D). Both T4 and T3 concentrations increased significantly during the L period of the daily cycle and decreased during the D period of the cycle; A.M. versus P.M. differences in free thyroxin indices (FTI) were also studied using the T4 and T3 uptake assays of Nuclear Medical Laboratories (Dallas, Texas). The free thyroxin index was significantly greater in serum samples of hamsters sacrificed at 7 P.M. than at 7 A.M. (lights on at 6:30 A.M.). Serum taken at 7 P.M. had less unsaturated binding sites than serum taken at 7 A.M. No significant A.M. versus P.M. differences in free thyroxin index were found in blind hamsters, although blind hamsters had significantly lower T4 and FTI than controls. Placing melatonin in the drinking water at a dose of 80 μg/ml did not significantly influence hormone levels. The greatest difference in hormone concentrations between control and blinded hamsters was found in P.M. samples. Blind hamsters had FTIs that were 48% of P.M. controls. Pinealectomy prevented the effects of blinding on T4 levels and FTIs.
Effects of Melatonin and Control Injections on Pineal Serotonin and Norepinephrine: Afternoon Injections Lower Serotonin Levels Thirty‐Six Percent at Light‐Dark Transition
Authors: Catalá M. Dolores , Du Ji‐zeng , Quay W.B. , Timiras P.S.
Published: February 2007

Pineal weight and serotonin (5‐HT) and norepinephrine (NE) contents were studied in male Sprague‐Dawley rats that were maintained under controlled light:dark conditions (LD 14:10; lights on 0700‐2100) and that received daily subcutaneous injections of either melatonin (20 μg in 0.1 ml per animal) or the same volume (0.1 ml) of vehicle alone, at one of two times (0800‐0900 or 1800‐1900). Animals were sacrificied at four times (1000, 1400, 2000, or 2300) on the day after the last of the 7 consecutive d of injection. Pineal glands were quickly weighed and then frozen for 5‐HT and NE assay by the Maickel and Miller extraction and fluorescence methods.

Pineal NE content showed differences related to time of day, in confirmation of early work. But no effects attributable specifically to melatonin were found. Melatonin also failed to affect pineal 5‐HT content significantly. But injection of either melatonin or vehicle at 1800‐1900 led to a reduction in 5‐HT content averaging 36% when sampled at either 2000 or 2300, and in comparison with animals injected at 0800‐0900. It is suggested that a stresslike or zeitgeberlike effect of injections within a critical period at the end of the daily light phase can cause an earlier‐than‐normal daily fall in pineal 5‐HT content.
The Influence of Various Irradiances of Artificial Light, Twilight, and Moonlight on the Suppression of Pineal Melatonin Content in the Syrian Hamster
Authors: Brainard George C. , Richardson Bruce A. , Hurlbut Edward C. , Steinlechner Stephan , Matthews Susan A. , Reiter Rüssel J.
Published: February 2007

The purpose of the present studies using artificial light was to determine how the timing and duration of exposure influence the light‐induced suppression of pineal melatonin levels in hamsters. An 8‐min exposure to 0.186 μW/cm2 of cool white fluorescent light caused a continued depression of pineal melatonin even when animals were returned to darkness. In addition, the pineal gland does not appear to change its sensitivity to light throughout the night. A 20‐min exposure to 0.019 μW/cm2 of cool white fluorescent light did not significantly suppress pineal melatonin during any time of the melatonin peak, whereas a 20‐min exposure to 0.186 μW/cm2was capable of always suppressing melatonin. Furthermore, increasing the duration of 0.019‐μW/cm2 exposure to 30, 60, 120, or 180 min does not increase the capacity of this irradiance to depress melatonin.

Similar to artifical light, natural light has a variable capacity for suppressing nocturnal levels of pineal melatonin. Twilight irradiances of 0.138 μW/cm2 or less did not suppress nocturnal melatonin whereas twilight irradiances of 3.0 μW/cm2 or greater did suppress pineal melatonin. A few animals did have lower melatonin after a 40‐min exposure to full moonlight during July (0.045 μW/cm2) or January (0.240 μW/cm2). However, pineal melatonin levels remained high in the majority of animals exposed to full moonlight.
No Correlation of Pineal “Synaptic” Ribbon Numbers and Melatonin Formation in Individual Rat Pineal Glands
Authors: Vollrath Lutz , Welker Horst A.
Published: February 2007

As previous circadian studies of pineal “synaptic” ribbon numbers and melatonin formation suggested that a positive correlation of the two variables exists, in the present investigation this problem was examined in individual pineal glands of rats killed at 1200 h and 2400 h, respectively. For this purpose, one half of the gland was processed for electron microscopy and the ribbons were counted in an area of 20,000 μm2 tissue; in the other half serotonin N‐acetyltransferase (NAT) activity and melatonin content were determined. No correlation was found to exist between ribbon numbers and pineal NAT activity, pineal melatonin levels and serum melatonin levels, either at day‐ or at nighttime. It is concluded that the ribbons may perhaps be more closely related to the innervation of the pineal gland than to melatonin formation.
Effect of Short Photoperiod on Hypothalamic Methionine‐Enkephalin and LHRH Content and Serum β‐Endorphin‐Like Immunoreactivity (β‐end LI) Levels in Golden Hamsters
Authors: Kumar M.S.A. , Besch E.L. , Millard W.J. , Sharp D.C. , Leadem C.A.
Published: February 2007

Adult female golden hamsters were used to study the effect of short photoperiod on the endogenous opioid system and the effect of pinealectomy on the serum β‐endorphin‐iike immunoreactivity (β‐end LI) levels. Hamsters were housed under either long photoperiod (14L:10D) or short photoperiod (2L:22D) and the regularity of the estrous cycles was determined by daily vaginal exfoliative cytology. Hamsters under short photoperiod became acyclic after about 7 wk. At the end of 8 wk, all the hamsters were decapitated and medial basal hypothalamic (MBH) content of LHRH and methionine‐enkephalin (met‐enkephalin) were measured by specific radioimmunoassays (RIA). Both LHRH and met‐enkephalin levels of the MBH were significantly elevated in the short‐photoperiod hamsters as compared to the normally cycling control animals under long photoperiod. In a second experiment, the effect of pinealectomy (PNX) on the serum levels of β‐end LI in the short‐photoperiod hamsters was determined. The serum β‐end LI levels were increased approximately threefold in the noncyclic hamsters housed under 8 wk of short‐photoperiod conditions. Pinealectomized hamsters kept under 8 wk of short‐photoperiod exhibited lower serum β‐end LI levels similar to those of normally cycling hamsters kept under long photoperiod. These results indicate a possible functional relationship between increased pineal activity (as a result of short photoperiod) and increased MBH met‐enkephalin, LHRH, and serum β‐end LI levels.
Characterization of Dopaminergic Receptor Sites in Bovine Pineal Gland
Authors: Govitrapong Piyarat , Murrin L. Charles , Ebadi Manuchair
Published: February 2007

In addition to β‐adrenergic receptor agonists, L‐dopa and dopamine have been also shown to activate the production of melatonin and its synthesizing enzyme, serotonin N‐acetyltransferase. In an attempt to characterize dopaminergic receptor sites, bovine pineal synaptosomes were prepared by differential centrifugation techniques. Washed disrupted synaptic membranes were used to study 3H‐spiroperidol binding, using standard membrane‐binding techniques. Association of 3H‐spiroperidol to pineal membranes was very rapid, reaching equilibrium within 2 min and remaining stable for 20 min. Dissociation was also rapid with a t½ of 3 min. Analysis of saturation studies (0.035 to 20 nM spiroperidol, 16 concentrations) using the LIGAND program indicated the presence of two binding sites with KDs (dissociation equilibrium constant) of 0.18 nM and 2.1 nM. The Bmax's (receptor density) of the sites were 37 and 630 fmoles/mg protein respectively. The IC50s of haloperidol, cis‐flupenthixol, and chlorpromazine were 8, 12, and 80 nM, respectively, while those of pipamperone, cyproheptadine, and cinanserin were 60, 400, and 1500 nM. These and other data indicate that the most abundant site is a dopamine D2 receptor while the less abundant site may be a serotonin receptor. The function of dopamine and dopaminergic neurons in bovine pineal gland is not known and has not been established.
Pineal Neural Connections With the Brain in Two Teleosts, the Crucian Carp and the European Eel
Authors: Ekström Peter , van Veen Theo
Published: February 2007

The neural connections between the pineal organ and the brain were investigated in two teleost species: the crucian carp and the European eel. Horseradish peroxidase (HRP) was administered into the pineal parenchyma in vivo or in vitro. After 12–96 hours, the brains were fixed, and HRP was reacted in frozen sections with either diaminobenzidine (DAB) or Hanker‐Yale's reagent. The HRP had entered the pineal neurons, and had labeled their axonal processes (the pineal tract) in a Golgi‐like manner. In both species, HRP‐labeled axons were observed in the habenular nuclei, the pretectal area, the dorsal and ventral thalamus, the dorsal periventricular tegmentum, and in the posterior periventricular hypothalamus. In the eel, single axons were also observed in the anterior hypothalamus and in the brain stem. Thin, varicose (preterminal) axons were observed in great numbers in the pretectal area and dorsal thalamus in both species, and in small numbers in the habenular nuclei and posterior periventricular hypothalamus. For comparison, the retinofugal projections were visualized after intraocular HRP‐injection. A close association of retinal and pineal terminal fields were noted in the pretectal area and the dorsal thalamus, whereas other diencephalic retinal and pineal recipient areas seem more segregated.
Synaptic Junctions Between the Adrenergic Axon Varicosity and the Pinealocyte in the Rat
Authors: Huang Hung‐Tu , Lin Huai‐San
Published: February 2007

Intercellular relationships of sympathetic nerve fibers and cells in pineal glands of Long‐Evans rats and yellow‐bellied country rats (Rattus losea Swinhoe) were studied with conventional electron microscopy. Typical synapses were found between adrenergic axon varicosities and pinealocytes. The synaptic cleft was 20–30 nm thick and contained granular or filamentous material of moderate electron density. Some small granulated vesicles attached to, or fused with, the presynaptic axolemma, a feature suggesting an exocytotic release of the vesicle content. The occurrence of membranous cisternae or tubules in the synaptic nerve ending may connote the phenomenon of synaptic vesicle recycling. Beneath the postsynaptic pinealocyte plasmalemma there was a dense plaque corresponding to the postsynaptic density of neurons. Possible origins and functional significance of the synapse‐making nerve fibers are also discussed.
Differential Effect of Carbidopa on the Concentration of Rat Pineal and Hypothalamic Indoleamines
Authors: Oxenkrug Gregory F. , Mclntyre Iain M. , Novak Edward A. , Hryhorczuk Lew M. , Frohman Charles E.
Published: February 2007

Carbidopa, an aromatic acid decarboxylase inhibitor, has been shown to significantly decrease the pineal concentration of melatonin, N‐acetyl serotonin (NAS), serotonin (5‐HT), and 5‐hydroxyindoleacetic acid (5‐HIAA) but not the hypothalamic concentrations of these indoles. Increased levels of 5‐hydroxytryptophan (5‐HTP) indicate that carbidopa directly inhibits 5‐HTP decarboxylation, thus limiting 5‐HT production. Possible practical implications of selective inhibition of pineal indoleamines by carbidopa are discussed.
Entrainment of the Circadian Rhythm in Rat Pineal N‐Acetyltransferase Activity Under Extremely Long and Short Photoperiods
Authors: Illnerová Helena , Vaněček Jiří
Published: February 2007

Entrainment of a pacemaker driving the circadian rhythm in rat pineal N‐acetyltransferase activity was studied under extremely long and short photoperiods. Adult male rats maintained under the light‐dark regime (LD) 18:6 or under the regime LD 6:18 were exposed to a I‐min light pulse at different times at night, then they were released into darkness, and the next night phaseshifts of the evening N‐acetyltransferase rise and of the morning N‐acetyltransferase decline caused by light pulses were determined. The evening rise was phase‐delayed by at most 0.5 h under LD 18:6, but by as much as 2.8h under LD 6:18. The morning decline was phase‐advanced by at most 1.9 h under LD 18:6, but by as much as 3.5 h under LD 6: 18. Hence, the magnitude of phaseshifts and consequently patterns of phase‐response curves, which show possibilities of discrete entrainment, depend on the photoperiods under which animals are maintained. A 1‐min light pulse applied within 1 h before the end of the dark period phase‐advanced the morning N‐acetyltransferase decline under LD 18:6 as well as under LD 6:18, while a pulse applied within 1 h after the beginning of the dark period phase‐delayed the evening N‐acetyltransferase rise only in rats maintained under LD 18:6, but not in those kept under LD 6:18. It seems that under very long photoperiods, the N‐acetyltransferase rhythm may be entrained by evening as well as by the morning light, while under very short photoperiods the rhythm may be synchronized by morning light only.
An Investigation of Demethylation in the Metabolism of Methoxytryptamine and Methoxytryptophol
Authors: Leone R. M. , Silman R. E.
Published: February 2007

Though melatonin is primarily metabolised to 6‐hydroxy‐melatonin, we have recently shown that it can also be demethylated to form N‐acetyl‐serotonin. The question therefore arises as to whether demethylation is a general metabolic pathway that can apply to other pineal methoxyindoles. To investigate this possibility we administered deuterated methoxy‐tryptophol (dML) and deuterated methoxy‐tryptamine (dMT) to rats and analysed the urine for the presence of deuterated methoxyindole acetic acid (dMIAA) and deuterated hydroxyindole acetic acid (dHIAA). The method of analysis was gas chromatography mass spectrometry (GCMS), where the relevant molecular ion and fragment ions were monitored. The results showed that the major metabolite in all cases was dMIAA. There was no evidence to suggest that the compounds had been demethylated to form dHIAA. The study therefore indicates that the demethylation of melatonin is a specific metabolic pathway that does not apply to other methoxyindoles.
Photoperiodic Control of Testicular Size in the Golden Hamster: Lack of a Role for the Deep Pineal Gland
Authors: Anderson Keith D. , Turek Fred W.
Published: February 2007

Removal of the superficial pineal gland prevents testicular regression from occurring in golden hamsters exposed to a short‐day photoperiod, but to date no studies have examined the role of the deep pineal gland in the photoperiodic control of gonadal function. We investigated the role of the deep pineal gland in this process by monitoring testicular size in hamsters with an electrolytic lesion of the deep pineal gland. Sexually mature hamsters that had been sham‐lesioned or that had received a lesion aimed at the deep pineal gland were transferred from 14L: 10D to 6L: 18D or were maintained in 14L: 10D for 73 d. Testicular widths were determined at 2–3‐wk intervals and after 73 d the testes were removed and weighed. The mean testis widths of the seven animals with histologically confirmed deep pineal lesions and exposed to 14L: 10D remained large, similar to those of the sham‐operated control animals exposed to the same photoperiod. The testes regressed in the five animals with confirmed deep pineal lesions and exposed to 6L: 18D in a similar manner to those of the sham‐operated control animals exposed to the same photoperiod. No significant difference (P > 0.05) was found between the testicular weights of lesioned and unlesioned animals exposed to either photoperiod. The lack of a significant effect of a deep pineal lesion on testicular size demonstrates that this portion of the pineal complex is not required for normal regulation of testicular function by photoperiod. These results also suggest that nerve fibres projecting from the brain to the superficial pineal gland via the deep pineal gland are not involved in photoperiodic regulation of testicular function.
Melatonin Rhythms in Quail: Regulation by Photoperiod and Circadian Pacemakers
Authors: Underwood Herbert , Siopes Thomas
Published: February 2007

The profile of melatonin in the eyes, pineal, and blood of Japanese quail was assessed in birds held under LD 16:8 and LD 6: 18 photoperiods. Melatonin levels in all three tissues showed a robust daily rhythm with higher levels occurring at night. The amplitude of the rhythm was depressed and its duration lengthened on LD 6: 18 relative to LD 16:8. The blood melatonin rhythm precisely reflected the rhythms shown by the pineal and eyes, supporting the idea that the blood rhythm is a result of melatonin secretion by both the eyes and pineal.

The ocular melatonin rhythm continued after sectioning of the optic nerve, was reentrainable to a shift in the phase of the LD cycle, and persisted for at least 2 days in constant darkness. It was concluded that either (1) an intraocular circadian clock drives the ocular melatonin rhythm, or (2) an extraocular clock drives the ocular melatonin rhythm via a route other than the efferent innervation (which enters the eye via the optic tract).
Harderian Glands of Golden Hamsters: Temporal and Sexual Differences in Immunoreactive Melatonin
Authors: Hoffman Roger A. , Johnson Lucinda B. , Reiter Russel J.
Published: February 2007

Throughout a 24‐h period, immunoreactive melatonin concentrations in Harderian glands of female golden hamsters were approximately 200 pg/mg protein with a significant decline to 80 pg/mg protein only at about 0600, 2 h after light on. Concentrations in glands of males are diurnally constant and low (ca. 20 pg/mg protein). Castration increases immunoreactive melatonin in glands of males to female levels. While blinding alone had no effect, it did prevent the castration‐induced increase. Lower conentrations were measured in glands of blinded or blinded ovariectomized females but this decrease was not significant. These data suggest that immunoreactive melatonin concentrations in the Harderian glands of hamsters are controlled by testosterone or its derivatives; these same factors also control the male or female character of these glands.
Stereologic Studies on Mitochondrial Configuration in the Rat Pinealocytes
Authors: Krakowski Gerhard , Cieciura Leszek
Published: February 2007

Stereologic studies were performed on rat pinealocytes. In the morphometric analysis the following parameters were taken into consideration: the volume density of the outer and inner membranes, surface areas of the outer and inner membranes, inner membrane to outer membrane surface area ratio, volumes of the outer and inner compartments, and partition coefficients of these compartments. Visual analysis demonstrated three mitochondrial configurational states. Based on the mitochondrial criteria, the existence of three pinealocyte types may be demonstrated. The authors believe that these are the cells in three different functional states.