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R Jozsa

Publications and source records attributed to R Jozsa.

14 recordsLinked to original sources
PubMed2005

Chronomics, neuroendocrine feedsidewards and the recording and consulting of nowcasts--forecasts of geomagnetics.

A multi-center four-hourly sampling of many tissues for 7 days (00:00 on April 5-20:00 to April 11, 2004), on rats standardized for 1 month in two rooms on antiphasic lighting regimens happened to start on the day after the second extremum of a moderate double magnetic storm gauged by the planetary geomagnetic Kp index (which at each extremum reached 6.3 international [arbitrary] units) and by an equatorial index Dst falling to -112 and -81 nT, respectively, the latter on the first day of the sampling. Neuroendocrine chronomes (specifically circadian time structures) differed during magnetically affected and quiet days. The circadian melatonin rhythm had a lower MESOR and lower circadian amplitude and tended to advance in acrophase, while the MESOR and amplitude of the hypothalamic circadian melatonin rhythm were higher during the days with the storm. The circadian parameters of circulating corticosterone were more labile during the days including the storm than during the last three quiet days. Feedsidewards within the pineal-hypothalamic-adrenocortical network constitute a mechanism underlying physiological and probably also pathological associations of the brain and heart with magnetic storms. Investigators in many fields can gain from at least recording calendar dates in any publication so that freely available information on geomagnetic, solar and other physical environmental activity can be looked up. In planning studies and before starting, one may gain from consulting forecasts and the highly reliable nowcasts, respectively.

Animals↗
PubMed2005

Circadian and extracircadian exploration during daytime hours of circulating corticosterone and other endocrine chronomes.

During 7 consecutive days, blood and several tissues were collected during daytime working hours only, three times per day at 4-h intervals from inbred Wistar rats, which had been previously standardized for 1 month in two rooms on a regimen of 12 h of light (L) alternating with 12 h of darkness (LD12:12). In one room, lights were on from 09:00 to 21:00 and in the other room, lights were on from 21:00 to 09:00 (DL12:12; reversed lighting regimen). This setup provides a convenient design to study circadian and extracircadian variations over long (e.g., 7-day) spans. Prior checking of certain circadian rhythms in animals reared in the room on reversed lighting (DL) as compared with animals in the usual (LD) regimen provided evidence that the 180 degrees phase-shift had occurred. These measurements were limited to the circadian (and not extended to infradian) variation. As marker rhythm, the core temperature of a subsample of rats was measured every 4 h around the clock (by night as well as by day) before the start of the 7-day sampling. An antiphase of the circadian rhythm in core temperature was thus demonstrated between rats in the LD vs. DL rooms. A sex difference in core temperature was also found in each room. A reversed rhythm in animals kept in DL and an antiphase between rats kept in DL vs. LD was again shown for the circulating corticosterone rhythm documented in subsamples of 8 animals of each sex sampled around the clock during the first approximately 1.5 day of the 7-day sampling. The findings were in keeping with the proposition that sampling rats at three timepoints 4 h apart during daytime from two rooms on opposite lighting regimens allows the assessment of circadian changes, the daytime samples from animals kept on the reversed lighting regimen accounting for the samples that would have to be obtained by night from animals kept in the room with the usual lighting regimen. During the 7-day-long follow-up, circadian and extracircadian spectral components were mapped for serum corticosterone, taking into account the large day-to-day variability. A third check on the synchronization of the animals to their respective lighting regimen was a comparison (and a good agreement) between studies carried out earlier on the same variables and the circadian results obtained on core temperature and serum corticosterone in this study as a whole. The present study happened to start on the day of the second extremum of a moderate double magnetic storm. The study of any associations of corticosterone with the storm is beyond our scope herein, as are the results on circulating prolactin, characterized by a greater variability and a larger sex difference than corticosterone. Sex differences and extracircadian aspects of prolactin and endothelin determined in the same samples are reported elsewhere, as are results on melatonin. Prior studies on melatonin were confirmed insofar as a circadian profile is concerned by sampling on two antiphasic lighting regimens, as also reported elsewhere. Accordingly, a circadian map for the rat will eventually be extended by the result of this study and aligned with other maps with the qualification of the unassessed contribution in this study of a magnetic storm.

Animals↗
PubMed2005

Chronomics reveal and quantify circadian rhythmic melatonin in duodenum of rats.

A circadian rhythm is documented in duodenal melatonin in rats, peaking 16.8 hours after light onset. This component is more readily detected after log10-transformation of the data. It differs between male and female rats, females having a larger circadian amplitude and an earlier acrophase. The circadian rhythm in duodenal melatonin is also found to lead that of pineal melatonin. The results are qualified by the presence at the start of mapping of the second extremum of a double magnetic storm.

Animals↗
PubMed2000

Quantum clock synchronization based on shared prior entanglement

We demonstrate that two spatially separated parties (Alice and Bob) can utilize shared prior quantum entanglement, and classical communications, to establish a synchronized pair of atomic clocks. In contrast to classical synchronization schemes, the accuracy of our protocol is independent of Alice's or Bob's knowledge of their relative locations or of the properties of the intervening medium.

Journal Article↗
PubMed1995

Immunohistochemical localization of pregnancy-related placental protein 4 in human placenta, umbilical cord and adult human female genital tissues.

Placental protein 4 (PP4) is a soluble placental tissue protein which was isolated from human placenta. The aim of the present study was to demonstrate the localization of cells containing PP4 in human placenta and in various female genital tissues under normal conditions. PP4 immunoreactive structures were demonstrated by using the peroxidase-antiperoxidase immunohistochemical technique. The samples were obtained from normal human placenta, umbilical cord, uterine cervix, endometrium, ovary and vulva. The most differentiated trophoblastic cells, the syncytiotrophoblasts, as well as the intermediate trophoblast cells contained PP4. PP4 immunoreactivity was present in umbilical cord as well. Occasionally PP4 was detected in normal ovarian, endometrial or vulvar tissue samples. Cervix and myometrium were free of PP4 immunoreactive material. PP4 staining was cytoplasmic. Our findings indicate that PP4 cannot be considered specific for the placenta since it is present in some human adult tissues as well.

Annexin A5↗
PubMed1994

Immunohistochemical localization of pregnancy-related placental protein 4 in nontumorous tissues and in gynecological tumors.

The aim of the study was to demonstrate the localization of placental protein 4 (PP4) in different nontumorous and tumorous tissues originating from the female genital tract. PP4 immunoreactivity was demonstrated using the peroxidase-antiperoxidase immunohistochemical technique. Tissue samples were obtained from the cervix and body of the uterus, ovary, vulva and from gestational trophoblastic tumors. PP4-positive cells were present in nontumorous tissues with various pathologic findings, and in many but not all benign gynecological tumors. Similar numbers of PP4-positive cells were located in malignant and benign gynecological tumors; however, PP4 staining intensity was greater in the malignant lesions. PP4-positive cells were found in hydatidiform moles and in choriocarcinoma. PP4 was distributed mainly in the cytoplasm, but it was also bound to the cell membrane. We conclude from these studies that PP4 is located in a variety of benign and malignant cells of the female genital tract and that these cells may be the source of plasma PP4 found in patients with these conditions.

Female↗