711 research outputs found
The topography of the superficial veins of the hind leg in the baboon Papio anubis in comparison with the superficial veins of the lower limb in humans
Our studies were carried out on 8 male and 2 female baboons Papio anubis
cadavers. We examined a total of 20 hind legs. The vessels of the hind leg were
filled with coloured latex. Afterwards we prepared the superficial and deep veins
and accompanying arteries. We paid attention to the location, diameter and the
course of the long and short saphenous veins. We found many differences between
the system of superficial veins in the baboon hind leg and that in the
human lower limb. First of all, the long saphenous vein in the baboon Papio
anubis presented as two similar trunks that ran together with a concomitant
artery. The saphenofemoral junction was also duplicated. The distance between
these outlets was about 4 mm and their location was different from that in
humans. Neither trunk exceeded 2.5 m in diameter.
Some human-like features were noticed in the system of the short saphenous
vein in Papio anubis. The diameter of the short saphenous vein and its course
and the location of the saphenopopliteal junction were very similar to those in
humans. On the other hand, the short saphenous vein was the main superficial
venous channel of the hind limb of Papio anubis
Changes in the wall of the great saphenous vein at consecutive stages in patients suffering from chronic vein disease of the lower limbs
The aim of the study was to show the changes in the great saphenous vein
(GSV) wall at consecutive stages in the development of chronic vein disease
(CVD) in patients qualified for a surgical procedure after physical examination and Doppler ultrasonography. Four groups of patients were formed (C2, C3, C4
and C5/6) according to clinical stage of the CEAP classification (C - clinical
signs, E - aetiopathology, A - anatomy and P - pathophysiology). After the
surgical procedure for removal of the varicose GSVs, 40 segments were harvested from their proximal parts near the saphenofemoral junction, 10 segments for each CEAP group. The veins were sectioned transversally and stained with the resorcin-fuchsin and AZAN method to visualise the elastic end collagen fibres. Afterwards the specimens were analysed under an optical microscope and photographed.
As the GSV is an elastic vessel and its wall is divided into three zones,
namely the internal layer (intima), the medial layer (media) and the external layer (adventitia), we found a proliferation of the connective tissue among the smooth muscle cells inside the internal and medial layers at consecutive stages of CVD. The later stages of CVD also revealed a larger number of the elastic and collagen
fibres inside the intima and media and a looser arrangement of the smooth
muscle cells of the media in the GSV wall
Measurement of 131I activity in thyroid of nuclear medical staff and internal dose assessment in a Polish nuclear medical hospital
This paper presents results of 131I thyroid activity measurements in 30 members of the nuclear medicine personnel of the Department of Endocrinology and Nuclear Medicine Holy Cross Cancer Centre in Kielce, Poland. A whole-body spectrometer equipped with two semiconductor gamma radiation detectors served as the basic research instrument. In ten out of 30 examined staff members, the determined 131I activity was found to be above the detection limit (DL = 5 Bq of 131I in the thyroid). The measured activities ranged from (5 ± 2) Bq to (217 ± 56) Bq. The highest activities in thyroids were detected for technical and cleaning personnel, whereas the lowest values were recorded for medical doctors. Having measured the activities, an attempt has been made to estimate the corresponding annual effective doses, which were found to range from 0.02 to 0.8 mSv. The highest annual equivalent doses have been found for thyroid, ranging from 0.4 to 15.4 mSv, detected for a cleaner and a technician, respectively. The maximum estimated effective dose corresponds to 32% of the annual background dose in Poland, and to circa 4% of the annual limit for the effective dose due to occupational exposure of 20 mSv per year, which is in compliance with the value recommended by the International Commission on Radiological Protection
Periodic One-Dimensional Hopping Model with one Mobile Directional Impurity
Analytic solution is given in the steady state limit for the system of Master
equations describing a random walk on one-dimensional periodic lattices with
arbitrary hopping rates containing one mobile, directional impurity (defect
bond). Due to the defect, translational invariance is broken, even if all other
rates are identical. The structure of Master equations lead naturally to the
introduction of a new entity, associated with the walker-impurity pair which we
call the quasi-walker. The velocities and diffusion constants for both the
random walker and impurity are given, being simply related to that of the
quasi-particle through physically meaningful equations. Applications in driven
diffusive systems are shown, and connections with the Duke-Rubinstein reptation
models for gel electrophoresis are discussed.Comment: 31 LaTex pages, 5 Postscript figures included, to appear in Journal
of Statistical Physic
Effect of chemical modifications on modulation of gene expression by duplex antigene RNAs that are complementary to non-coding transcripts at gene promoters
Antigene RNAs (agRNAs) are small RNA duplexes that target non-coding transcripts rather than mRNA and specifically suppress or activate gene expression in a sequence-dependent manner. For many applications in vivo, it is likely that agRNAs will require chemical modification. We have synthesized agRNAs that contain different classes of chemical modification and have tested their ability to modulate expression of the human progesterone receptor gene. We find that both silencing and activating agRNAs can retain activity after modification. Both guide and passenger strands can be modified and functional agRNAs can contain 2′F-RNA, 2′OMe-RNA, and locked nucleic acid substitutions, or combinations of multiple modifications. The mechanism of agRNA activity appears to be maintained after chemical modification: both native and modified agRNAs modulate recruitment of RNA polymerase II, have the same effect on promoter-derived antisense transcripts, and must be double-stranded. These data demonstrate that agRNA activity is compatible with a wide range of chemical modifications and may facilitate in vivo applications
Miejscowe wycięcie nowotworów odbytnicy (LE) – alternatywa dla rozległych operacji brzusznych (LAR, APR)
Progression of SARS-CoV-2 seroprevalence in St. Louis, Missouri, through January 2021
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seropositivity was assessed for 3,066 individuals visiting hospitals in St. Louis, Missouri, during July 2020, November 2020, or January 2021. Seropositivity in children increased from 5.22% in July to 21.16% in January. In the same time frame, seropositivity among adults increased from 4.52% to 19.03%, prior to initiation of mass vaccination
E-Cadherin Is Transcriptionally Activated via Suppression of ZEB1 Transcriptional Repressor by Small RNA-Mediated Gene Silencing
RNA activation has been reported to be induced by small interfering RNAs (siRNAs) that act on the promoters of several genes containing E-cadherin. In this study, we present an alternative mechanism of E-cadherin activation in human PC-3 cells by siRNAs previously reported to possess perfect-complementary sequences to E-cadherin promoter. We found that activation of E-cadherin can be also induced via suppression of ZEB1, which is a transcriptional repressor of E-cadherin, by seed-dependent silencing mechanism of these siRNAs. The functional seed-complementary sites of the siRNAs were found in the coding region in addition to the 3′ untranslated region of ZEB1 mRNA. Promoter analyses indicated that E-boxes, which are ZEB1-binding sites, in the upstream promoter region are indispensable for E-cadherin transcription by the siRNAs. Thus, the results caution against ignoring siRNA seed-dependent silencing effects in genome-wide transcriptional regulation. In addition, members of miR-302/372/373/520 family, which have the same seed sequences with one of the siRNAs containing perfect-complementarity to E-cadherin promoter, are also found to activate E-cadherin transcription. Thus, E-cadherin could be upregulated by the suppression of ZEB1 transcriptional repressor by miRNAs in vivo
You turn me cold: evidence for temperature contagion
Introduction
During social interactions, our own physiological responses influence those of others. Synchronization of physiological (and behavioural) responses can facilitate emotional understanding and group coherence through inter-subjectivity. Here we investigate if observing cues indicating a change in another's body temperature results in a corresponding temperature change in the observer.
Methods
Thirty-six healthy participants (age; 22.9±3.1 yrs) each observed, then rated, eight purpose-made videos (3 min duration) that depicted actors with either their right or left hand in visibly warm (warm videos) or cold water (cold videos). Four control videos with the actors' hand in front of the water were also shown. Temperature of participant observers' right and left hands was concurrently measured using a thermistor within a Wheatstone bridge with a theoretical temperature sensitivity of <0.0001°C. Temperature data were analysed in a repeated measures ANOVA (temperature × actor's hand × observer's hand).
Results
Participants rated the videos showing hands immersed in cold water as being significantly cooler than hands immersed in warm water, F(1,34) = 256.67, p0.1). There was however no evidence of left-right mirroring of these temperature effects p>0.1). Sensitivity to temperature contagion was also predicted by inter-individual differences in self-report empathy.
Conclusions
We illustrate physiological contagion of temperature in healthy individuals, suggesting that empathetic understanding for primary low-level physiological challenges (as well as more complex emotions) are grounded in somatic simulation
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