Colforsin-induced vasodilation in chronic hypoxic pulmonary hypertension in rats

Purpose  

Colforsin, a water-soluble forskolin derivative, directly activates adenylate cyclase and thereby increases the 3′,5′-cyclic adenosine monophosphate (cAMP) level in vascular smooth muscle cells. In this study, we investigated the vasodilatory action of colforsin on structurally remodeled pulmonary arteries from rats with pulmonary hypertension (PH).     

Neuroimaging study on brain asymmetries in situs inversus totalis

Situs inversus totalis (SI) is a rare condition in which all visceral organs are arranged as mirror images of the usual pattern. The objective of this study was to determine whether SI individuals have reversed brain asymmetries. We performed a neuroimaging study on 3 SI subjects and 11 control individuals with normally arranged visceral organs. The language-dominant hemisphere was determined by magnetoencephalography. Left-hemispheric dominance was observed in 1 SI subject and all controls, whereas right-hemispheric dominance was observed in the remaining 2 SI subjects. Statistical analysis revealed that language dominance patterns in SI subjects were different from those in the controls, suggesting that the developmental mechanisms underlying visceral organ asymmetries are related to those underlying functional brain asymmetry. Anatomical brain asymmetries were determined by magnetic resonance imaging. SI subjects had the same planum temporale (PT) asymmetry pattern as the controls, but a reversed petalia asymmetry pattern. The inferior frontal gyrus (IFG) asymmetry pattern varied within both groups, indicating a relationship between the rightward IFG and right-hemispheric language dominance. These results suggest that the developmental mechanisms underlying visceral organ asymmetries are related to those underlying petalia asymmetry but not to those underlying PT and IFG asymmetries, and that brain asymmetries might develop via multiple region-dependent mechanisms.     

Differences in left ventricular hypertrophy and dysfunction between patients with cerebral hemorrhage and those with cerebral infarction

Left ventricular (LV) hypertrophy and dysfunction due to hypertension have been established as risk markers for stroke in hypertensive patients. The purpose of this study was to examine the differences in LV hypertrophy and dysfunction between patients with cerebral hemorrhage and those with cerebral infarction. The study enrolled 23 hypertensive patients with cerebral infarction, 25 hypertensive patients with cerebral hemorrhage, and 24 normotensive controls (controls). Standard echocardiography was performed; LV mass index was measured to evaluate LV hypertrophy, and conventional diastolic transmitral flow velocities were measured to assess LV diastolic function, which was also evaluated by measuring mitral annular velocities using tissue Doppler echocardiography. The Tei index, which reflects both the diastolic and systolic function of LV, was also calculated. The LV mass index and Tei index were significantly higher in cerebral hemorrhage (116 +/- 38 g/m(2) and 0.57 +/- 0.13) than those in controls (92 +/- 20 g/m(2) and 0.46 +/- 0.10) (p < 0.05). In contrast, the LV mass index and Tei index in cerebral infarction (100 +/- 27 g/m(2) and 0.46 +/- 0.12) were not different from those in controls. Thus, the Tei index was significantly worse in the patients with cerebral hemorrhage than in those with cerebral infarction (p < 0.05). On the other hand, the parameters, which reflect diastolic function, showed no significant differences between cerebral hemorrhage and cerebral infarction. These results indicate that LV hypertrophy and dysfunction due to hypertension are more apparent in patients with cerebral hemorrhage than in those with cerebral infarction.     

Initial bone regeneration around fenestrated implants in Beagle dogs using basic fibroblast growth factor–gelatin hydrogel complex with varying biodegradation rates

PurposeThe purpose of this study was to compare the effectiveness of fast and slow biodegradation of basic fibroblast growth factor (bFGF)–gelatin hydrogel complex on bone regeneration around fenestrated implants as a new augmentation drug delivery system.MethodsNine titanium implants (3.3 mm diameter and 10 mm length) were placed into the edentulous areas of the mandibles of three adult beagle dogs with four screws exposed at the upper buccal side. The effectiveness of bFGF–gelatin hydrogel complexes of varying degradation types used to cover implant screws without membrane were compared with 1 μg and 10 μg bFGF–98 wt% gelatin as the fast degradation type and 10 μg bFGF–95 wt% gelatin as the slow degradation type. After 4 weeks, bone regeneration around the screws was evaluated histologically and histomorphometrically.ResultsWith use of 10 μg bFGF, regenerated bone around exposed screws was clearly seen in both the fast and slow degradation type groups. In contrast, little bone formation was seen in the fast degradation-type group with 1 μg bFGF. Height of regenerated bone for the slow degradation-type complex group was significantly greater than for the fast degradation-type group with 1 μg bFGF (P < 0.05).ConclusionThese results suggest that use of slow degradation-type bFGF–gelatin hydrogel complex may accelerate bone regeneration around fenestrated implants at an early stage of bone regeneration.     

Lethal thrombus in the carotid artery during operation for acute aortic dissection with cerebral malperfusion

A drowsy patient with acute type A aortic dissection and cerebral malperfusion required emergency operation. Because the right carotid artery was totally obstructed, cerebral perfusion was first restored by cannulating it and the left femoral artery before midline sternotomy. However, a long fresh thrombus was found flowing backward from the obstructed carotid artery. This thrombus was removed, and both arteries were connected through a Y-shaped extracorporeal circulation circuit to reperfuse the brain. During the subsequent aortic procedure, both arteries were used for arterial inflow. Such thrombi can cause grave postoperative neurologic dysfunction. Carotid artery cannulation is mandatory in such cases.     

Effects of vitamin K2 in hemodialysis patients with low serum parathyroid hormone levels

In patients with adynamic bone disease, the bone contains few osteoblasts or osteoclasts and bone turnover is slow, so the risk of fracture is increased. The decrease of bone remodeling may also decrease the capacity of bone to buffer calcium, leading to an increase of the calcium x phosphate product and an increased risk of arterial calcification. Such findings emphasize that an effective treatment for adynamic bone disease is required. The present study investigated the influence of vitamin K2 (menatetrenone) on hemodialysis patients with low serum parathyroid hormone levels by using bone metabolism markers. The subjects were 32 hemodialysis patients (19 men and 13 women) aged from 27 to 76 years with an intact parathyroid hormone (PTH) level of less than 65 pg/ml and an intact osteocalcin level below 20 ng/ml. All patients received oral menatetrenone therapy (45 mg/day) for 12 months. To obtain control data on bone metabolism markers in hemodialysis patients with normal bone turnover, we selected 50 patients who had intact PTH levels within the range that maintains relatively normal bone turnover, that is, from 120 to 250 pg/ml. The baseline levels of all bone metabolism markers were significantly lower in our patients than in the normal PTH control group. There was a significant increase of gamma-carboxyglutamate (Gla) osteocalcin, bone alkaline phosphatase (B-ALP), tartrate-resistant acid phosphatase (TRACP), and cross-linked N-terminal telopeptide of type 1 collagen (NTx) levels after vitamin K2 administration. Type 1 procollagen carboxyterminal propeptide (P1CP) and intact osteocalcin both showed a significant increase after 12 months of treatment. Although there was no significant change of the alkaline phosphatase (ALP) level during the 12 months before the start of vitamin K2 therapy, there was a significant increase of alkaline phosphatase after vitamin K2 administration. Adjusted calcium, serum phosphate, and intact PTH showed no significant changes throughout the study. These changes of bone metabolism markers suggested that vitamin K2 therapy can improve bone remodeling in hemodialysis patients with low serum PTH levels.