bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐Term Effects of Pinealectomy on Testicular Function, Luteinizing Hormone‐Releasing Hormone Hypothalamic System, and Plasma Prolactin Levels in the Mink, a Short‐Day Breeder
Authors: Boissin‐Agasse L. , Jacquet J. M. , Lacroix A. , Boissin J. 
Published: February 2007

Experiments in minks, as in a number of other seasonal breeders, clearly demonstrate that the pineal gland is essential for the photoperiodic control of reproduction. While maintenance of pineal‐intact minks under natural photoperiods results in a set of seasonally appropriate changes in testicular activity, pinealectomized minks undergo none of these changes but rather remain sexually inactive as under long‐day conditions. Thus, the consequences of pinealectomy differ from one photoperiodic species to another, but the unifying feature is the organism's need for the pineal gland to respond appropriately to changes in day length.Although the precise mechanism by which the pineal regulates hypothalamic‐pituitary gonadal function remains unknown, the results of the present study indicate that, in the mink, luteinizing hormone‐releasing hormone axonal transport is affected by pinealectomy.Furthermore, our results suggest that the pineal does not act exclusively upon the neuroendocrine‐gonadal system but also acts on other functions that are influenced by photoperiod. Pinealectomized minks left in natural conditions cannot adjust their prolactin secretion in response to either long or short photoperiods. Operated animals continued to have plasma prolactin variations but at irregular intervals and with no apparent relation to the time of the year. The data strengthen the hypothesis that melatonin may act at some point on the hypothalamic neuroendocrine systems, which regulate the two functions differently, and that melatonin is not an anti‐ or progonadal substance but rather a seasonal transducer.
Presence of a Distinct 24‐Hour Melatonin Rhythm in the Ventricular Cerebrospinal Fluid of the Goat
Authors: Kanematsu Nobue , Mori Yuji , Hayashi Shinji , Hoshitio Kunio 
Published: February 2007

Melatonin profiles in the cerebrospinal fluid (CSF) of conscious goats were examined under long‐day (16L:8D) and short‐day (8L:16D) environments. CSF melatonin, collected from the lateral ventricle, showed distinct 24 h rhythms with high concentrations being restricted to the dark phase, which averaged 1,320.6 pg/ml under 16L:8D and 660.6 pg/ml under 8L:16D. On the contrary, the nocturnal rise in CSF melatonin was totally absent in the pineal sympathetically denervated animals. Night interruption by 1 h lighting (about 400 lux at the height of goat's head) resulted in an abrupt decline of CSF melatonin to the basal level within 30 min and immediate recovery to the previous high level after reestablishment of the dark phase. The CSF/plasma ratio was 10.8–18.4 during the dark phase and 1.7–1.8 during the light phase.CSF and plasma melatonin levels were also examined after exogenous melatonin given either peripherally or intraventricularly. Continuous subcutaneous infusion of melatonin (5 μg/h) maintained melatonin levels in the plasma about 3 times higher than that in the CSF during its application. On the other hand, an intraventricular injection of 2 μg melatonin elevated plasma melatonin by 100 pg/ml within 1 min.These results indicate that turnover of CSF melatonin is fairly rapid and favor a hypothesis for direct access of pineal melatonin to the brain ventricular system in the goat.
Scanning electron microscopic study on pineal vascularization of the common tree shrew (Tupaia glis)
Authors: Chunhabundit Panjit , Somana Reon 
Published: February 2007

Chunhabundit P, Somana R. Scanning electron microscopic study on pineal vascularization of the common tree shrew (Tupaia glis). J Pineal Res 1991 : 1059‐64.Abstract:The detailed blood supply including microvascularization of pineal gland in the common tree shrew (Tupaia glis) was investigated using a vascular corrosion cast technique in conjunction with scanning electron microscopy. Adult common tree shrews of both sexes, divided into 3 groups, were injected with red latex, blue vinyl resin, and Batson's No. 17 plastic mixture for the studies of arterial supply, venous drainage, and microvasculature of the pineal gland, respectively. It was found that the pineal gland is a highly vascularized organ. It receives two to four branches from the medial posterior choroidal arteries. Two types of capillary arrangements, fan‐like and network, are observed. As in the human, usually one and occasionally two pineal veins, draining directly into the great cerebral vein of Galen, are observed. A pineal portal system is not demonstrated.
Differential effects of pinealectomy on amygdala and hippocampus serotonin metabolism
Authors: Miguez Jesús , Martin Francisco , Aldegunde Manuel 
Published: February 2007

Miguez J, Martin F, Aldegunde M. Differential effects of pinealectomv on amygdala and hippocampus serotonin metabolism. J Pineal Res 1991 : 10: 1 W103.Abstract:The purpose of the present study was to determine the effects of long‐term pinealectomy on serotonin metabolism in the amygdala and the hippocampus of male rats. Pinealectomy did not significantly alter either tryptophan or serotonin concentrations in the amygdala or the hippocampus. However, statistically significant decreases in 5‐hyroxyindole‐3‐acetic acid levels and tryptophan hydroxylase activity were found in the amygdala. Monoamine oxidase activity was unchanged in both regions. These results support the involvement of the amygdaloid serotoninergic system in mediating the functions of the pineal gland.
Reliable analysis of individual human megaton profiles by complex cosinor analysis
Authors: Lerchl Alexander , Partsch Carl‐Joachim 
Published: February 2007

Lerchl A, Partsch C‐J. Reliable analysis of individual human melatonin profiles by complex cosinor analysis. J. Pineal Res. 1994: 16: 85–90.AbstractThe analysis of diurnal secretion patterns of the pineal hormone melatonin should provide information about magnitude of peak concentration, time of peak (acrophase), and duration of elevated hormone levels. We report here on a method for analysis of human melatonin secretary rhythms which fulfills these requirements with considerable precision. Blood samples were obtained from 10 healthy male volunteers at 30 min intervals throughout a 24 hr period, three times (the initial blood sampling was repeated after 2 weeks and 3 months). These sets of 48 plasma samples per volunteer were analyzed for melatonin by radio immunoassay. The mean intra‐assay variation was 10. 3%, and inter‐assay variations were 15. 8% at 21 pg/ml, 11% at 28 pg/ml, and 9. 4% at 48. 6 pg/ml. Data were subjected to single cosinor analysis (SCA) or analyzed by a complex cosinor analysis (CCA) with the fundamental and the first harmonic as parameters. Both methods provided essentially the same information about the macrophages, whereas the CCA had a clear advantage in terms of better regression coefficients between the original data points and the calculated curve (CCA: r = 0.952 ± 0.018; SCA: r = 0.867 ± 0.039 [means ± SD]; P < 0.001). As a consequence, maximum and minimum values and the times of onset and cessation of melatonin production could be estimated easily and reliably without the need for rough and/or subjective measures. By comparing the three sampling sessions, the secretary rhythm of each individual was clearly reproducible (mean coefficient of variation 8. 4%), thus confirming earlier work. Interindividual differences, however, were quite pronounced, especially with respect to amplitudes (more than 25% coefficient of variation). The present method for describing the secretary pattern of emblazoning may also be useful for other study protocols since it requires only slightly more effort than the commonly used single cosinor analysis.
Photoperiod and melatonin affect testicular growth in the marsh rice rat (Oryzomys palustris)
Authors: Edmonds Kent E. , Stetson Milton H. 
Published: February 2007

Edmonds KE, Stetson MH. Photoperiod and melatonin affect testicular growth in the marsh rice rat (Orgzonys palustris). J. Pineal Res. 1994: 17: 86–93. ©Munksgaard 1994AbstractReproduction in rice rats is subject to photoperiodic control and the pineal gland mediates this effect. We examined the effects of the pineal gland hormone melatonin on testicular weight when administered via implants, injections, and infusions. Testicular weight was modified by photoperiod and the size of the melatonin implant. Twenty‐millimeter implants suppressed testicular weight in rice rats housed on 12‐ and 16‐hr photoperiods, while those housed on a 14‐hr photoperiod were more sensitive to melatonin; in these animals 10‐ and 20‐mm implants inhibited testicular weight. Melatonin implants also prevented rice rats from responding to a change in photoperiod with the appropriate alteration of testicular growth. Melatonin injections inhibited testicular growth when administered before lights out on LD 14: 10, but not on LD 16: 8. Morning injections had no effect on either photoperiod. Finally, 12‐hr duration melatonin infusions inhibited testicular growth in pinealectomized rice rats on LD 16: 8, while 6‐hr duration infusions were without effect. These data show that the pineal, through the secretion of melatonin, is a phototransducing organ intimately involved in testicular growth in rice rats.
Are the annual reproductive and body weight rhythms in the male European hamster (Cricetus cricetus) dependent upon a photoperiodically entrained circannual clock?
Authors: Masson‐Pévet M. , Naimi F. , Canguilhem B. , Saboureau M. , Bonn D. , Pevet P. 
Published: February 2007

Masson‐Pévet M, Naimi F, Canguilhem B, Saboureau M, Bonn D, Pévet P. Are the annual reproductive and body weight rhythms in the male European hamster (Cricetus cricetus) dependent upon a photoperodically entrained circannual clock? J. Pineal Res. 1994; 17:151–163.AbstractMost or the data obtained so far on the European hamster (Cricetus cricetus) suggest direct photoperiodically driven seasonal changes in sexual activity and body weight. The results of the present long‐term study support the hypothesis that these annual changes are the expression of photoperiodically driven endogenous circannual rhythms. When subjected following capture (April‐May) to constant conditions of long photoperiod (LP) and constant temperature a large number of the European hamsters present, in September‐December, complete gonadal atrophy associated with a decrease in body weight. A sexual reactivation as well as an increase in body weight are observed in the same animals between January and April. Of the six animals that survived long enough, two only presented partial gonadal atrophy during the second year. These observations clearly demonstrate that the decline in sexual activity in subjective autumn does not require a decrease in photoperiod, at least in the first year. Theoretically, the observed rhythms, if circannual in nature, would be generated by a self‐sustained annual oscillator (circannual clock) able to function in the absence of a photoperiodic input. Pinealectomy makes animals unable to detect or measure photoperiodic information. Of the six European hamsters tested (pinealectomized in June and then kept continuously under LP), five showed clear annual rhythms in body weight and reproductive capacities for two consecutive years. Clearly endogenous annual rhythms were expressed in these conditions. To be entrained to a 1‐year period, such a circannual clock should, however, be able to react to either LP and/or to short‐photoperiod (SP), at least at certain periods of the annual cycle. In animals exposed to LP in August or October, after gondal atrophy had been established by exposure to natural SP, gonadal regrowth started in December or January, about 2 to 3 months earlier than in animals kept outside or in experimental SP. With the same experimental conditions, exactly the same results were obtained in pinealectomized animals; thus stimulatory effect of LP or LP‐induced phase advance of the circannual clock can be excluded. The absence of the SP information would then induce such reaction. In animals kept under constant LP and temperature following capture, however, pinealectomy in January—when all animals are sexually active—induces gonadal atrophy within 4 weeks. This clearly demonstrates that LP is stimulatory at this time of the subjective year.
Influence of melatonin and serotonin on glucose‐stimulated insulin release from perifused rat pancreatic islets in vitro
Authors: Peschke Elmar , Peschke Dorothee , Hammer Thomas , Csernus Valer 
Published: February 2007

Peschke E, Peschke D, Hammer T, Csernus V. Influence of melatonin and serotonin on glucose‐stimulated insulin release from perifused rat pancreatic islets in vitro. J. Pineal Res. 1997; 23:156–163. © Munksgaard, CopenhagenAbstractInsulin plays a key role in the control of glucose homeostasis in mammals. Insulin secretion is regulated by a coordinated interplay of several factors. The role of the indoleamines in the control of insulin secretion has not been fully elucidated yet. The present study was addressed to investigate the function of melatonin and serotonin in the direct control of insulin secretion from the pancreatic islets. Explanted rat Langerhans' islets were treated with melatonin or serotonin while also being exposed to specific (glucose) or non‐specific (KC1) stimulus either in a pulsatile or long‐term manner in a perifusion system. Insulin content from the effluent tissue culture media was analyzed with RIA. Pulsatile administration of melatonin and serotonin alone did not alter the basal insulin secretion from the explanted islets even at pharmacological (5 μM) level. However, insulin response to specific (glucose) or non‐specific (KC1) stimulus was significantly reduced while the islets were treated with melatonin (3 to 12 hr, 10 nM to 5 μM). This effect was reversible and repeatable. Both the start and end of the effect was rapid, evolving and disappearing within 10 min. On the other hand, under similar experimental protocol, serotonin (at 5 μM concentration) significantly enhanced both glucose and KC1 stimulated insulin release. Since the effect of the nonspecific stimulation (with KC1) was also altered, melatonin and serotonin seem to alter not only the release but also the synthesis of the insulin. Our data show that melatonin and serotonin have a direct effect on the insulin secretion from the pancreatic islets.
Effect of estrogen on melatonin synthesis in female peripubertal rats as related to adenylate cyclase activity
Authors: Okatani Yuji , Hayashi Kazutoshi , Sagara Yusuke 
Published: February 2007

Okatani Y, Hayashi K, Sagara Y. Effect of estrogen on melatonin synthesis in female peripubertal rats as related: Relation to adenylate cyclase activity. J. Pineal Res. 1998; 25:245–250. © Munksgaard, CopenhagenAbstractTo determine the mechanism for the modulatory effect of estrogen on melatonin synthesis, we evaluated the effects of estrogen on the activity of adenylate cyclase in female Sprague‐Dawley rats of peripubertal age. Adenylate cyclase activity was measured in homogenates of pineal glands from rats aged 3 and 10 weeks in the mid‐dark and in the mid‐light. Ovariectomy was performed and a subcutaneous injection of estradiol benzoate (E2B) was administered daily starting at the age of 6 weeks. A peak in adenylate cyclase activity in the pineal gland was observed in untreated (control) rats with intact ovaries at 4 weeks. Ovariectomy at week 6 led to significant increases in the activity of adenylate cyclase at week 8. At week 10, adenylate cyclase activity resembled that of control animals. The subcutaneous injection of E2B (1.0 (Ag/day) suppressed the increase in adenylate cyclase activity induced by ovariectomy, similar to the level seen in control rats with intact ovaries. The changes in the mid‐light activity of pineal adenylate cyclase resembled that seen at the mid‐dark with the value being significantly lower than that observed in the mid‐dark. Such changes in the mid‐dark activity of adenylate cyclase resembled those observed with N‐acetyltransferase (NAT) at the same time, as previously described. Results suggest that estrogen modulates adenylate cyclase activity in the pineal gland of peripubertal female rats. The decline in melatonin synthesis during puberty may be related to an increase in estrogen level. The inhibitory effect of estrogen on melatonin synthesis appeared to be mediated by a change in the norepinephrine‐induced stimulation of pineal adenylate cyclase activity.
Tape‐stripping method in man: comparison of evaporimetric methods
Authors: Zhai Hongbo , Dika Emi , Goldovsky Marina , Maibach Howard I. 
Published: February 2007

Background/purpose: If the occlusion time of a closed chamber evaporimeter on the skin is too long, saturation might occur. We previously compared an open chamber and a closed chamber device on healthy volunteers. Comparable data on stripped skin with higher evaporation rates are not available. This study compares the sensitivity and correlation of open and closed chamber devices in a tape‐stripping human model. The amount of tape removed SC was also quantified with a protein assay method.Methods: Ten healthy volunteers (six male and four female; seven Caucasians and three Asian; mean age 38±16) were enrolled. In a randomized manner, one forearm was measured by an open chamber device and the opposite by a closed chamber device. After recording baseline measurements, 20 strippings were taken on each test site with tape disks. Transepidermal water loss (TEWL) was measured at the end of 10 and 20 tape strippings at each test site. Stratum corneum (SC) aggregates in the strips was assayed.Results: The mean values obtained from two devices were similar after 10 trips and 20 strips. There was no statistically significant difference. The closed chamber device showed a slightly higher (but not significant) inter‐individual coefficient of variation. SC aggregates in the strips were similar and without a statistically significant difference.Conclusion: The study suggests that both devices might yield similar TEWL values on stripped human skin in vivo.
PROCESSING WHEY‐TYPE BY‐PRODUCT LIQUIDS FROM COTTONSEED PROTEIN ISOLATION WITH ULTRAFILTRATION AND REVERSE OSMOSIS MEMBRANES
Authors: LAWHON J. T. , LIN S. H. C. , HENSLEY D. W. , CATER C. M. , MATTIL K. F. 
Published: February 2007

ABSTRACTCottonseed wheys resulting from protein isolation from cottonseed flour were processed by semi‐permeable ultrafiltration (UF) and reverse osmosis (RO) membranes. The UF membrane fractionated the soluble whey constituents by retaining protein and passing through salts, carbohydrates and other non‐protein components along with most of the water. The UF membrane effluent was then processed through an RO membrane to recover a secondary product containing the whey materials not retained in the protein product from the UF membrane.The feasibility of recycling effluent from the RO membrane for reuse in subsequent protein extractions was demonstrated. Thus, the threat of water pollution from effluent disposal could be eliminated completely and process water requirements drastically reduced.Spray‐dried UF protein concentrates were tested for utilization in protein fortification of breads and noncarbonated beverages and as whipping products. They exhibited commercial potential for use in these food applications.The economics of processing the whey‐type liquids by the membrane process under investigation were analyzed. Membrane processing of wheys by each of two alternative whey processing systems proved to be economically attractive.
EFFECT OF STORAGE AND PROCESSING CONDITIONS ON SORGHUM KERNEL STRENGTH
Authors: SUTER D. A. , RUPP R. A. , LANE G. T. , SULLINS R. D. 
Published: February 2007

ABSTRACTCompressive strength of sorghum kernels was measured to determine the effect of storage conditions on processing for animal feed. Ensiling grain affected a larger decrease in kernel compressive strength than did storage at a high moisture level. Results similar to the above were noted for tests conducted on kernels obtained from animal feces. Microscopic examination of kernels from each treatment revealed greater removal of kernel structure for those of lower compressive strength.
ENERGY CONSUMPTION FOR REFRIGERATED, CANNED, AND FROZEN PEAS
Authors: RAO M. A. 
Published: February 2007

ABSTRACTThe energy inputs at different stages in the total food cycle of peas were estimated for the market modes: refrigerated, frozen, and canned. The energy accounting showed for refrigerated 3,368; for canned 3,637; and for frozen 3,281 Btu/2.8‐oz serving. Because the energy consumption for each market mode is of the same order of magnitude, there is little reason for the consumer to select on bases other than availability, taste preference, and convenience. It was also found that energy for packaging, marketing, shopping, and in the home can be high depending on the market mode. Measures to reduce energy consumption are discussed for several sectors.
PREDICTION OF FREEZING TIMES FOR FOODS AS INFLUENCED BY PRODUCT PROPERTIES
Authors: HSIEH R. C. , LEREW L. E. , HELDMAN D. R. 
Published: February 2007

ABSTRACTThis investigation utilizes a computer simulation technique to predict the freezing times and temperature history curves for food products. The input information consists of the product properties for temperatures above the initial freezing point, freezing medium conditions and the initial product temperature.It has been established that food products with lower initial freezing points, higher initial water contents and higher initial product densities will have longer freezing times. The prediction of freezing time is most sensitive to the accuracy of the measurement of the product density and the initial freezing point if the freezing point is above −0.5°C. The influence of the accuracy of unfrozen product thermal conductivity data on the freezing time is not important in the range of 0.45 to 0.55 W/m°K investigated. The combined influence of inaccuracy in measuring these product properties on the freezing time prediction will be significant even if the influence of an individual product property is small.
MASS TRANSFER CHARACTERISTICS OF HOLLOW FIBER ULTRAFILTRATION OF SOY PROTEIN SYSTEMS
Authors: CHERYAN MUNIR 
Published: February 2007

ABSTRACTMass transfer characteristics and the applicability of theoretical transport models in ultrafilitration were evaluated in a pilot‐scale hollow fiber system processing soybean water extracts. Permeate flux was found to increase linearly with transmembrane pressure and then reach an asymptotic value. Substantial deviations from the pure water permeation line and marked hysteresis effects were also observed, indicative of concentration polarization and additional hydrodynamic resistance at the membrane surface. Pressure‐independence occurred at lower pressures with lower Reynolds Numbers (Re) and higher Schmidt Numbers (Sc). Flow rate and temperature significantly affected flux in the totally polarized region. The exponent in the flux‐Reα relationship varied from 0.6 at 20°C to 0.32 at 50°C. Theoretical laminar flow mass transfer models were found to predict Sherwood Numbers (Sh) and flux lower than experimental values. The correlation that fit the data best was Sh = 0.181 (Re).47 (Sc).33