Fixation of atmospheric carbon dioxide by ruthenium complexes bearing an NHC-based pincer ligand: formation of a methylcarbonato complex and its methylation.

A methylcarbonato ruthenium complex was prepared by capture of CO2 from air using the (CNC)(bpy)Ru scaffold. The methylcarbonato complex was relatively inert to decarboxylation. Treatments with methylating reagents released dimethylcarbonate.

Early fetal development of the rotator interval region of the shoulder with special reference to topographical relationships among related tendons and ligaments.

PURPOSE: There is a little information on the early fetal development of the rotator interval region of the shoulder, particularly with regard to whether topographical relationships among the ligaments and tendons change during development. METHODS: We examined the histological sections (transverse or frontal) of right or left shoulder in 20 mid-term human fetuses (7-15 weeks of gestation). RESULTS: The biceps tendon had an accompanying bursa-like cavity before the joint cavitation. The bursa for the tendon remained open to the joint cavity until 12 weeks. When reaching the glenoid, the biceps tendon involved and carried mesenchymal tissue around the coracoid process (the future coracohumeral ligament) toward the infraspinatus tendon. Until 10 weeks, the primitive glenohumeral ligament was established as simple collateral ligaments on the inner or humeral side of the rotator cuff tendons and the biceps long tendon. However, the subscapularis tendon crossed, attached to, and reformed the upper structure of the superior glenohumeral ligament. CONCLUSIONS: The early development of the coracohumeral ligament suggests that it is a primitive and basic structure. However, we hypothesize that mechanical demands from the subscapularis tendon and biceps long tendon are likely to change the primitive form of the rotator interval to the adult morphology, including the superior glenohumeral ligament. The significant modification evident during early fetal development suggests that anatomical reconstruction after rotator cuff tears should not be based on the "ideal" anatomy, especially that of the superior glenohumeral ligament, but on individual requirements.

Contribution of the anterior longitudinal ligament to ossification and growth of the vertebral body: an immunohistochemical study using the human fetal lumbar vertebrae.

Using 15 mid-term human fetuses, we examined the role of the spine anterior and posterior longitudinal ligaments (ALL, PLL) in ossification of the lumbar vertebral body. By 18 weeks, a pair of calcified tissue or cortical walls had developed on the anterior and posterior sides of the ossification center. These calcified cortical walls were more highly eosinophilic than trabecular or woven bone in the ossification center. Vimentin-positive osteoblasts were arranged in line along the outer surface of the walls. However, few CD68-positive osteoclasts were evident around the walls, suggesting that the calcification in the walls was similar to periosteal ossification. The anterior cortical wall was connected tightly with the ALL by fiber bundles, but the posterior wall was separated from the PLL by the basivertebral (central) vein and loose tissues. Notably, by 30 weeks, the anterior cortical wall had become attached to and incorporated into the ALL. Thus, the ALL seemed to act as an active periosteum for ossification. Although our materials were limited in number and stage, we hypothesized that, in contrast to the PLL, the mature anterior cortical wall corresponds to a calcified fibrocartilage adjacent to the ALL and forms a bone-ligament interface maintaining an ossification potential.

Human fetal anatomy of the posterior semimembranosus complex at the knee with special reference to the gastrocnemio-semimembranosus bursa.

There is little information on the fetal anatomy of the posterior semimembranosus tendinous complex and its associated bursa. We examined histological sections (transverse or sagittal) of the right or left knee in 13 mid-term human fetuses (12-25 weeks of gestation). The medial head of the gastrocnemius provided an aponeurosis facing or attached to the muscles of the pes anserinus by 12 weeks of gestation. The peritendinous tissue of the semimembranosus provided a bursa continuous with a laterally extending plate-like tissue by 15 weeks, but sometimes the typical bursa was absent. The aponeurosis of the medial head consistently accompanied a bursa-like space (false bursa) surrounded by heterogenous structures including the popliteus and a wall of the semimembranosus bursa. Sagittal sections displayed notches on the medial head surface that received the semimembranosus and semitendinosus overriding the medial head of the gastrocnemius. In contrast to a real bursa originating from the peritendinous tissue of the semimembranosus, a false bursa without a homogeneous wall consistently develops at the origin of the medial head of the gastrocnemius. Due to mechanical stress from the tendons, the false bursa is likely to develop into a structure similar to a real bursa with a synovial lining even if the real bursa is absent in the fetus. We hypothesize that the adult gastrocnemio-semimembranosus bursa, largely or partly, originates from the fetal false bursa. Absolute resection of the false bursa is difficult because it is a mere gap between normal tissues.

Expression of intermediate filaments at muscle insertions in human fetuses.

Desmin and vimentin are intermediate filaments that play crucial roles in the maturation, maintenance and recovery of muscle fibers and mesenchymal cells. The expression of these proteins has not been investigated extensively in human fetuses. In the present study, we examined the immunohistochemical expression of intermediate filaments in skeletal muscles of the head, neck and thorax in 12 mid-term human fetuses at 9-18 weeks of gestation. We also used immunohistochemistry to localize the expression of the myosin heavy chain and silver impregnation to identify the fetal endomysium. Expression of desmin and vimentin was already detectable in intercostal muscle at 9 weeks, especially at sites of muscle attachment to the perichondrium. At this stage, myosin heavy chain was expressed throughout the muscle fibers and the endomysium had already developed. Beginning with punctate expression, the positive areas became diffusely distributed in the muscle fibers. At 15-18 weeks, intermediate filament proteins were extensively expressed in all of the muscles examined. Expression at the bone-muscle interface was continuous with expression along the intramuscular tendon fibres. These results suggest that the development of intermediate filaments begins in areas of mechanical stress due to early muscle contraction. Their initially punctate distribution, as observed here, probably corresponds to the earliest stage of fetal enthesis formation.

Fetal anatomy of peripheral lymphatic vessels: a D2-40 immunohistochemical study using an 18-week human fetus (CRL 155 mm).

We demonstrated fetal peripheral lymphatic vessels (LVs) using D2-40 immunohistochemistry in a whole female fetus (18 weeks of gestation, CRL 155 mm) except for the head. There were abundant LVs in the thyroid gland, lung, stomach, small intestine, rectum and pancreas, whereas no LVs were seen in the parathyroid gland, spleen and adrenal cortex. In the liver, except for the gallbladder bed, LVs were still restricted to around hilar thick portal veins and around the hepatic vein terminals. Subcutaneous LVs were well developed throughout the body even in areas where no or few perforating LVs connected with the deep LVs. The diaphragm contained abundant, dilated LVs in the pleural half of its thickness. LVs were also seen not only along supplying arteries of muscles and cartilage but also along the epimysium and perichondrium. LVs ran in a space between the obliquus internus and transversus abdominis but not between the obliquus internus and obliquus externus. Some tight connective tissues such as the sacrotuberous ligament contained abundant LVs. The intervertebral foramen contained a lymphatic plexus. The present observations provide a better understanding of peripheral lymphatic development. The fetal lymphatic morphology seems not to represent a mini-version of the adult morphology.

Effect of auditory stimulation on parasympathetic nerve activity in urethane-anesthetized rats.

Previously, it has been demonstrated that auditory stimulation with music (Traeumerei [TM] by Schumann) decreased renal sympathetic nerve activity (RSNA) and blood pressure (BP) with a central mechanism, while it is unknown whether TM affects parasympathetic nerve activity. Here, the effects of auditory stimulation with TM on gastric vagal nerve activity (GVNA) in urethane-anesthetized rats were investigated. Auditory stimulation with TM, but not with white noise (WN) caused a significant elevation of GVNA. In addition, exposure to TM increased the number of c-Fos-immunoreactive cells in the auditory cortex (AuC). These findings suggest that exposure to music can increase GVNA through the auditory pathway.

The influence of increasing sacroiliac joint force closure on the hip and lumbar spine extensor muscle firing pattern.

The prone hip extension (PHE) test is commonly used in the evaluation of lumbo-pelvic dysfunction. It has been suggested that altered motor control identified by the PHE test can be improved with the application of compression force across the pelvis, to increase force closure on the sacroiliac joint (SIJ). This repeated measure study design investigated the effect of three levels of pelvis compression (0N, 50N, 100N) on the muscle firing pattern during the PHE test in 20 asymptomatic male subjects tested on two occasions 4-weeks apart. The right gluteus maximus, right semitendinosus and bilateral lumbar erector spinae were analyzed using surface electromyography (EMG). Subjects were instructed to perform right hip extension in prone position while maintaining knee-extension in each measurement condition. Compared with the onset of the semitendinosus muscle, gluteus maximus became active 263.3+/-99.5 ms later with no pelvic compression, 183.5+/-77.9 ms later with 50N compression, 91.5+/-49.7 ms later with 100N compression. While significant differences (alpha=0.05) were found in EMG onset for gluteus maximus under different levels of pelvis compression, this was not the case for the erector spinae, which had an inconsistent pattern of temporal onset and was not influenced by the level of pelvis compression force.

Day-night difference in thermoregulatory responses to olfactory stimulation.

Previously, we observed that olfactory stimulation with scent of grapefruit oil (SGFO) or scent of lavender oil (SLVO) affected, elevated or lowered brown adipose tissue temperature (BAT-T) in conscious mice, respectively. In the present study, to test the day-night difference in the actions of olfactory stimulations, we examined the responses of BAT-T and body temperature (BT) measured as the abdominal temperature to SGFO or SLVO during day-time at 14:00 and night-time at 2:00 in conscious rats. In the light period, BAT-T and BT were suppressed after SLVO and elevated after SGFO whereas in the dark period, these parameters remained unchanged with olfactory stimulations. Bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) eliminated the effects of olfactory stimulations with SGFO and SVLO on BAT-T and BT. Moreover, sympathetic nerve activity innervating brown adipose tissue (BAT-SNA) changes after SGFO or SLVO were abolished in SCN-lesioned rats. Thus, we concluded that there is day-night difference in the effects of SGFO or SLVO on BAT-T and BT, and that the SCN might be involved in these effects.

Effects of central injection of L-carnosine on sympathetic nerve activity innervating brown adipose tissue and body temperature in rats.

In the present study, using urethane-anesthetized rats, we examined the effects of intralateral cerebral ventricular (LCV) injection of various doses of L-carnosine on neural activity innervating brown adipose tissue (BAT-SNA) and body temperature (BT). We found that injection of a low dose of L-carnosine (0.01 microg) suppressed BAT-SNA significantly. Conversely, a high dose (100 microg) of L-carnosine significantly elevated BAT-SNA. In the light period (14:00), brown adipose tissue temperature (BAT-T) and BT were suppressed after low and elevated after high dose injection of L-carnosine whereas in the dark period (2:00), these parameters remained unchanged with L-carnosine treatment. Bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) abolished the effects of low and high doses of L-carnosine on BAT-SNA, BAT-T and BT. Furthermore, high dose treatment with L-carnosine altered c-Fos induction in the SCN and the PVN. These results suggest that l-carnosine affects BAT-SNA, BAT-T and BT in a dose-dependent manner in the rat, and that the SCN may be involved in these effects.

Auditory stimulation affects renal sympathetic nerve activity and blood pressure in rats.

Here, we examined the effects of auditory stimulation at 50 dB with white noise (WN) or music (Traeumerei [TM] by Schumann or Etude by Chopin) on renal sympathetic nerve activity (RSNA) and BP in urethane-anesthetized rats. Auditory stimulation with TM, but not with WN or the Etude, significantly decreased RSNA and BP. Complete bilateral destruction of the cochleae and bilateral lesions of the auditory cortex (AuC) eliminated the effects of TM stimulation on RSNA and BP, but bilateral lesions of primary somatosensory cortex (S1C) had no effect. Bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) or intracerebral administration of thioperamide, a histaminergic H3 receptor antagonist, also abolished TM-induced decreases in RSNA and BP. These findings suggest that exposure to music can decrease RSNA and BP through the auditory pathway, histaminergic neurons, and the SCN.

Mechanism of changes induced in plasma glycerol by scent stimulation with grapefruit and lavender essential oils.

In a previous study, we found that stimulation with scent of grapefruit oil (SGFO) elevated plasma glycerol levels in rats. However, stimulation with scent of lavender oil (SLVO) triggered a negative effect. To identify the mechanism of these changes during lipolysis, we examined the role of autonomic blockers and bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) in the modification of plasma glycerol in rats exposed to SGFO and SLVO. We found that intraperitoneal injection of propranolol hydrochloride and atropine sulfate eliminated the changes in plasma glycerol levels induced by SGFO and SLVO, respectively. Bilateral lesions of the SCN completely abolished the effects of SGFO and SLVO on lipolysis. In addition, we investigated tyrosine phosphorylation of the transmembrane glycoprotein BIT (a brain immunoglobulin-like molecule with tyrosine-based activation motifs, a member of the signal-regulator protein family), which was found to be involved in the activation of renal sympathetic nerves and increase in body temperature on cold exposure. SGFO was found to enhance the immunoreactivity of BIT to the 4G10 anti-phosphotyrosine antibody in the SCN, whereas SLVO decreased the immunoreactivity. The changes in BIT phosphorylation resulting from the exposure to SGFO and SLVO were eliminated by the corresponding histamine receptor antagonists, which eliminated the changes in plasma glycerol concentration. The results suggest that SGFO and SLVO affect the autonomic neurotransmission and lipolysis. The SCN and histamine neurons are involved in the lipolytic responses to SGFO and SLVO, and tyrosine phosphorylation of BIT is implicated in the relevant signaling pathways.

Morphometrical study of arteries and veins in the human sheet-like muscles (pectoralis major, latissimus dorsi, gluteus maximus and trapezius) with special reference to a paradoxical venous merging pattern of the trapezius.

The trapezius is one of the critical targets of physical therapy for shoulder functional disorder because this muscle plays a great role in fixation and elevation of the shoulder. Trapezius (n = 63), latissimus dorsi (n = 5), pectoralis major (n = 7) and gluteus maximus (n = 7) muscles were obtained from 43 donated cadavers, and vascular morphologies were compared. An artery without a concomitant vein was found in 35 of 63 trapezius muscles. Moreover, twice as many venous merging sites as arterial branching sites were present in the trapezius. Notably, peripheral or distal venous tributaries were larger in caliber than the proximally located vein in 6.2% of all 404 venous merging sites in the trapezius. Moreover, similar paradoxical venous merging, in which tributaries were relatively thicker than drainage capacity of the venous trunk after merging according to Poisueille's law (peripheral or distal thickness >0.85 x proximal thickness), was observed in 39.1% (158 of 404 merging sites) in the trapezius, compared to 8-9% in the other 3 muscles. Given this vascular morphology, trapezius muscle seems likely to frequently display venous blood retention. Interestingly, venous valves were not observed in the trapezius, compared to 1-7 valves per one of the other 3 muscles. Abundant venous mergings without valves might form a venous network acting as a reservoir. Therefore, for the trapezius, collateral venous routes such as the external vertebral plexus are essential to provide additional peripheral drainage. However, sufficient muscle-pump function does not seem to be expected for trapezius muscle, given the venous courses parallel to muscle fibers.

Olfactory stimulation with scent of lavender oil affects autonomic neurotransmission and blood pressure in rats.

Previously, we observed that olfactory stimulation with scent of lavender oil (SLVO) suppressed sympathetic nerve activities and elevated gastric vagal (parasympathetic) nerve activity (GVNA), decreased plasma glycerol concentration and body temperature, and enhanced appetite in rats. Here, we further showed that olfactory stimulation with SLVO lowered renal sympathetic nerve activity (RSNA) and blood pressure (BP) and elevated GVNA in urethane-anesthetized rats. Olfactory stimulation with linalool, a component of lavender oil, also elicited decreases in RSNA and BP and an increase in GVNA in urethane-anesthetized rats. Anosmia induced by pretreatment of the nasal cavity by application of ZnSO4 eliminated the effects of both SLVO and scent of linalool on RSNA, GVNA and BP. Furthermore, intracerebroventricular administration of thioperamide, a histaminergic H3-antagonist, abolished the suppression of RSNA and BP as well as the elevation of GVNA mediated by both SLVO and scent of linalool. Finally, bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) eliminated RSNA and BP suppression and the elevation of GVNA due to SLVO or linalool. Thus, it was concluded that scent of lavender oil and its active component, linalool, affects autonomic neurotransmission and reduces blood pressure through the central histaminergic nervous system and the SCN.

Olfactory stimulation with scent of essential oil of grapefruit affects autonomic neurotransmission and blood pressure.

Previously, we observed that olfactory stimulation with scent of grapefruit oil (SGFO) enhances sympathetic nerve activities and suppresses gastric vagal (parasympathetic) nerve activity (GVNA), increases plasma glycerol concentration and body temperature, and decreases appetite in rats. Here, we show that olfactory stimulation with SGFO for 10 min elevates renal sympathetic nerve activity (RSNA) and blood pressure (BP) and lowers GVNA in urethane-anesthetized rats. Olfactory stimulation with limonene, a major component of grapefruit oil, also elicited increases in RSNA and BP in urethane-anesthetized rats. Anosmic treatment with ZnSO(4) eliminated both the effects of SGFO and scent of limonene on RSNA and BP. Intracerebral administration of diphenhydramine, a histaminergic H1-antagonist, abolished SGFO- or scent of limonene-mediated increases in RSNA and BP as well as the decrease in GVNA. Moreover, bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) eliminated the SGFO- and limonene-mediated increases in RSNA and BP and decrease in GVNA, but bilateral lesions of the cerebral cortex did not have any affect on these parameters. These findings suggest that scent of grapefruit oil and its active component, limonene, affect autonomic neurotransmission and blood pressure through central histaminergic nerves and the suprachiasmatic nucleus.