Primary superficial vein reflux with competent saphenous trunk

OBJECTIVES

because reflux in superficial vein tributaries is most often collectively reported with the main saphenous veins, its importance remains largely unrecognised. This study was designed to identify the distribution and extent of non-truncal superficial venous reflux and its association with the signs and symptoms of chronic venous disease (CVD).

PATIENTS AND METHODS

eighty-four limbs in 62 patients with signs and symptoms of CVD and evidence of reflux on continuous-wave Doppler were subsequently examined with colour-flow duplex imaging. Incompetent superficial vein tributaries were imaged throughout their extent and both ends were identified. Limbs with reflux in the main trunk of the saphenous veins or the deep, perforator or muscular veins, superficial or deep vein thrombosis, injection sclerotherapy, varicose-vein surgery, arterial disease and inflammation of non-venous origin were excluded from the study. The CEAP classification system was used for staging clinical severity of CVD.

RESULTS

the prevalence of tributary reflux alone was 9.7% (84/860). Reflux was detected in 171 tributaries. The number of incompetent tributaries ranged from 1 to 5 per limb. Most prevalent were the tributaries to the greater saphenous (111, 65%<0. 0001), followed by those of lesser saphenous (33, 19%) or a combination of both (12, 7%). Incompetent non-saphenous tributaries were uncommon (15, 9%). Among the named tributaries in the lower limb the posterior arch vein was most often incompetent (46, 27%) followed by the anterolateral vein of the thigh (30, 18%), the medial accessory vein (16, 9%) and the anterior arch vein (14, 8%). Reflux in above-the-knee tributaries alone was found in 18 limbs (21%), in below the knee in 23 (28%) and in both sites in 43 (51%). The vast majority of the limbs (71%,p <0.0001) belonged to CVD class 2, 14% in class 3, 9% in class 1 and only 6% in class 4. Class 3 and 4 patients tended to have a longer duration of signs and symptoms, higher number of incompetent tributaries per limb and also a higher prevalence of combined above- and below-knee reflux.

CONCLUSIONS

these data indicate that reflux confined to superficial tributaries is found throughout the lower limb. Because this reflux is present without greater and lesser saphenous trunk, perforator and deep-vein incompetence or proximal obstruction, it shows that reflux can develop in any vein without an apparent feeding source. Greater saphenous tributaries are affected significantly more often than those of lesser saphenous, while non-saphenous reflux is uncommon. Most limbs have signs and symptoms of CVD class 2 and 15% belong in classes 3 and 4.

New insights into perforator vein incompetence

BACKGROUND

there has been much controversy on the role of perforator veins in the development of chronic venous disease (CVD). This study was designed to determine the duration and direction of flow of lower limb perforator veins (PVs) in relation to their location, diameter and competency status of superficial and deep veins, in healthy volunteers and patients with different grades of CVD.

PATIENTS AND METHODS

thirty limbs in 15 symptom-free volunteers and 103 limbs in 75 patients with signs and symptoms of CVD were examined with colour-flow duplex scanning. Superficial, perforator and deep veins were studied in the standing and sitting positions. Flow-velocity characteristics, the number and maximum PV diameter at the deep fascia and subfascially were determined. A PV was considered incompetent when the outward flow lasted >0.5 s.

RESULTS

581 PVs were found in the patients and 106 in the volunteers. 163 PVs (28%) were incompetent in the first group and none in the latter. The total number of PVs and the number of incompetent PVs per limb increased significantly with the severity of CVD. The mid-calf area had more competent and incompetent PVs in patients (p <0.01). Mean diameter of incompetent PVs in all the CVD classes was significantly larger than that of competent PVs. Competent PVs tended to be larger with increasing severity of CVD and they were significantly larger in the CVD classes 4 to 6 compared to controls (p <0.01). Subfascial PV diameter was markedly larger than that at the fascial level (p <0.001) regardless of the CVD class. A subfascial PV diameter of >3.9 mm (95% CI 3.4 to 4.4 mm) indicated incompetence. However, the reverse was not true, because about a third of incompetent PVs had a subfascial diameter of <3.9 mm. Both competent and incompetent PVs were smaller when located at the lower thigh, knee, ankle and anterior aspect of the calf than those found in the rest of the calf and mid-thigh (p =0. 03). Both inward and outward flow was found more often in patients than in controls (70/418 vs. 9/106, p =0.048). Most incompetent PVs had outward flow alone (126, 77%). PV incompetence was most frequently associated with reflux in superficial veins (120, 74% (p <0.0001), followed by reflux in both the superficial and deep veins (34, 21%) and reflux in the deep veins alone (9, 5%). The mean duration of outward flow was markedly longer in the presence of both superficial and deep vein reflux compared to superficial (p <0.001) or deep vein reflux alone (p <0.0001).

CONCLUSIONS

the number of incompetent PVs and the diameter of both competent and incompetent PV increases with the severity of CVD. Bidirectional PV flow is more common in patients than in normal volunteers, while 77% of the incompetent PVs have outward flow alone. PV incompetence is most often associated with reflux in the superficial veins, indicating that deep venous reflux is rarely the primary cause of PV insufficiency.

Localization of dopamine D1 and D2 receptor mRNAs in the rat systemic and pulmonary vasculatures

The present study was designed to evaluate the expression of dopamine D1 and D2 receptor mRNAs in systemic and pulmonary vasculatures. Using specific antisense riboprobes for dopamine D1 and D2 receptor cDNAs, in situ hybridization histochemistry was performed in the aorta, common carotid artery, vertebral artery, pulmonary artery, and superior vena cava of the adult male Sprague Dawley rat. In the case of the aorta, common carotid artery, and vertebral artery, dopamine D1 receptor mRNAs localized mainly in the smooth muscle cells of the tunica media. However, the signals of dopamine D2 receptor mRNAs were found in the endothelium and subendothelial layer of tunica intima, and interstitial cells of tunica adventitia. In the case of the pulmonary artery, signals of dopamine D1 receptor mRNAs were detected within the tunica intima, media, and adventitia. Expression of D2 receptor mRNAs was detected in the walls of small blood vessels within the tunica adventitia of the pulmonary artery. There were no detectable signals of dopamine D1 and D2 receptor mRNAs in the vein. The uneven distribution of dopamine D1 and D2 receptor mRNAs in the rat systemic vasculatures and pulmonary artery suggests that dopamine differentially regulates the vasodilation of the systemic and pulmonary arteries through the differential stimulation of dopamine D1 and D2 receptor.

Isolation of a new cerebroside from the root bark of aralia elata

A new cerebroside, named Aralia cerebroside (1), was isolated from the root bark of Aralia elata. The structure of 1 was determined to be 1-O-beta-D-glucopyranosyl-(2S,3S,4R, 8E)-2-[(2'R)-2'-hydroxypalmitoylamino]-8-octadecene-1,3,4-triol on the basis of physicochemical and spectroscopic studies.

Inhibition of mouse ear edema by steroidal and triterpenoid saponins

Certain steroids and triterpenoids isolated from diverse plant families were known to possess anti-inflammatory activity. In the course of finding new anti-inflammatory natural products, some steroidal and triterpenoid saponins were isolated and evaluated for their anti-inflammatory activity using in vivo mouse ear edema test. At the oral dose of 100 mg/kg, several steroidal saponins and triterpenoid saponins such as hederagenin glycosides showed significant inhibition of ear edema (20-37% inhibition), though less potent than indomethacin and hydrocortisone.

Inhibition of rat adjuvant-induced arthritis by ginkgetin, a biflavone from ginkgo biloba leaves

Ginkgetin, a biflavone isolated from Ginkgo biloba leaves, was previously reported as an inhibitor of group II phospholipase A2. In this study, ginkgetin was evaluated for in vivo antiarthritic and analgesic activities. Ginkgetin (10-20 mg/kg/day) strongly reduced arthritic inflammation in an animal model of rat adjuvant-induced arthritis (86% inhibition at 16 days at a dose of 20 mg/kg/day) via intraperitoneal injection, while prednisolone (5 mg/kg/day) showed 79% reduction. Histological examination of the knee joints confirmed our findings. When analgesic activity was measured, ginkgetin showed a dose-dependent inhibition in an animal model of acetic acid-induced writhing. ED50 values for ginkgetin and indomethacin were 8.9 and 3.8 mg/kg, respectively. All these results indicate that ginkgetin may be a potential antiarthritic agent having analgesic activity.

Akt protein kinase enhances human telomerase activity through phosphorylation of telomerase reverse transcriptase subunit

With the amino acid sequences of all reported Akt kinase physiological substrates, the possible Akt kinase substrate specificity has been suggested. The serine/threonine residue to be phosphorylated in these proteins is placed within stretches of amino acids with homology, and the arginine residues on the -5 and -3 positions and a hydrophobic amino acid on the +2 position are conserved relative to those of serine/threonine residues (XXRXRXXS/TXX). We noticed two putative Akt kinase phosphorylation sites (220GARRRGGSAS229) and (817AVRIRGKSYV826) in human telomerase reverse transcriptase (hTERT) subunit. To demonstrate that hTERT is an Akt kinase substrate protein, we performed the nonradioactive protein kinase assay with the fluorescein hTERT peptide (817AVRIRGKSYV826). We observed the phosphorylation of hTERT peptide by the human melanoma cell lysate or the activated recombinant Akt kinase proteins in vitro. With the treatment of the growth factor deprivation or okadaic acid, we also observed the up-regulation of both hTERT peptide phosphorylation and the telomerase activity. We noticed that Wortmannin down-regulates hTERT peptide phosphorylation and telomerase activity together. In addition, we observed the enhancement of telomerase activity with the pretreatment of Akt kinase in vitro. Thus, these observations suggest that Akt kinase enhances human telomerase activity through phosphorylation of hTERT subunit as one of its substrate proteins.

Timing and frequency of perioperative carotid color-flow duplex scanning: A preliminary report

PURPOSE

The results of intraoperative and early postoperative carotid color-flow duplex scanning (CFS) after endarterectomy were reviewed to determine whether any perioperative studies could be eliminated.

METHODS

Patients undergoing carotid endarterectomy with intraoperative CFS between 1986 and 1997 were identified. Early postoperative CFS was performed between 1 day and 3 weeks postoperatively, then it was performed again at 6 months postoperatively.

RESULTS

During the study period, 560 patients, 325 men and 235 women, underwent 621 carotid endarterectomies. A satisfactory intraoperative carotid CFS was completed in 611 (98.4%) patients. There were 20 (3.2%) vessels with a major defect that required revision for fronds or flaps (n = 11), retained atheroma (n = 5), low flow (n = 2), high velocity or turbulence (n = 1), or dissection (n = 1). Another 146 vessels (23.5%) had minor defects, such as retained proximal atheromas or small (less than 3 mm) fronds, but were not revised. The remaining 445 vessels were normal. The first postoperative CFS was normal in all the revised carotids and in 138 (94.5%) vessels with minor intraoperative defects. At 6 months, recurrent stenosis (more than 75% area reduction) was identified in 1 of 18 revised carotids (5.5%), 4 of 138 vessels (2. 9%) with minor defects, and 17 of 406 vessels (4.2%) that were normal intraoperatively. The incidence of recurrent stenosis was not significantly different in the three groups (P =.7).

CONCLUSION

Intraoperative CFS is useful because major unsuspected defects can be corrected immediately, thus avoiding potential neurologic morbidity. However, the postoperative day 1 CFS can be eliminated in most cases, because it does not provide any relevant clinical information.

Anterior cervical spinal epidural abscess in an infant

Spinal epidural abscess (SEA) is rare in children, especially in newborns and infants, groups in which only very few cases have been reported. Because of the nonspecificity of presenting symptoms in children the diagnosis may be delayed, resulting in major permanent neurological deficits. In this paper, we report a case of cervical SEA in a 6-week-old infant who initially presented with fever and developed quadriparesis 19 days prior to admission. After emergency anterior decompression of the abscess the neurological function was improved immediately. Five months after surgery the neurological status was normal, an MR study showing disappearance of the epidural abscess and spinal cord indentation, and progressive fusion of the C3, C4 and C5 vertebral bodies. Anterior decompression without bone graft can provide an excellent prognosis in case of an anterior cervical SEA in infants.

Negative regulation of gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor gene expression by a gonadotrophin-releasing hormone agonist in the rat hypothalamus

There exists evidence for the presence of ultrashort loop feedback circuits of gonadotropin-releasing hormone (GnRH) secretion in the hypothalamus. It is, however, uncertain whether a similar mechanism is involved in the regulation of GnRH gene expression in vivo. Furthermore, little is known about the regulation of GnRH receptor (GnRHR) expression in the brain. In the present study, we examined the regulation of GnRH and its receptor gene expression by GnRH in vivo. A GnRH agonist, [D-Ala6, des-Gly10]GnRH-ethylamide (des-Gly GnRH), was administered by intracerebroventricular (i.c.v.) injection via the lateral ventricle of ovariectomized and estradiol (OVX + E)-treated rats. The amounts of GnRH and GnRHR mRNA were measured in the preoptic area (POA) and posterior mediobasal hypothalamus (pMBH) micropunch samples from individual rat brain slices by respective competitive reverse transcription-polymerase chain reactions. The i.c.v. administration of des-Gly GnRH significantly decreased GnRH and GnRHR mRNA expression in a dose-and time-related manner: des-Gly GnRH (6 ng) suppressed GnRH and GnRHR mRNA expression within 2 h, and the suppression was maintained without significant variation until 8 h after treatment. Treatment with Antide, [N-Ac-D-Nal(2)1, pCl-D-Phe2, D-Pal(3)3, Lys(Nic)5, D-Lys(Nic)6, Lys(iPR)8, D-Ala10]GnRH (10 ng), a potent GnRH antagonist, did not alter GnRH mRNA expression, but prevented des-Gly GnRH-induced suppression of GnRH mRNA expression. Antide alone decreased GnRHR mRNA expression, but failed to alter agonist-induced suppression of GnRHR mRNA expression. These results demonstrate the existence of an ultrashort loop feedback mechanism for GnRH gene expression in the POA, along with homologous down-regulation of GnRHR mRNA expression in the pMBH.

Outcome of moderate carotid artery stenosis in patients who are asymptomatic

PURPOSE

The incidence rate of disease progression and stroke after the diagnosis of a moderate (50% to 79%) carotid stenosis was determined by means of color-flow duplex scanning.

METHODS

During a 4-year period, 344 male veterans with moderate internal carotid artery stenoses, on one or both sides, were examined at regular intervals for a mean period of 25 months. Carotid color-flow scans were obtained semiannually. Clinical follow-up was performed to determine the incidence rate of amaurosis fugax, transient ischemic attacks, nonhemispheric symptoms, and strokes.

RESULTS

New neurologic symptoms developed in 75 patients (21.8%). Fifty-one (14.8%) had ipsilateral symptoms during follow-up: 18 amaurosis fugax (5.2%), 14 transient ischemic attacks (4%), 5 nonhemispheric symptoms (1.4%), and 14 strokes (4%). Twenty-four patients (6.9%) had contralateral symptoms: 20 strokes (5.8%) and 4 transient ischemic attacks (1.2%). Life-table analysis showed that the annual rate of ipsilateral neurologic events was 8.1%, and the annual rate of stroke was 2.1%. Seventy-five patients (22%) died in the follow-up period. Disease progression to 80% to 99% stenosis or occlusion occurred in 71 of 458 vessels (15.5%). The internal carotid arteries that showed evidence of disease progression had a significantly higher initial peak systolic velocity (251 vs 190 cm/s; P <.0001) and end diastolic velocity (74 vs 52 cm/s; P < 0.0001). Black patients and patients with ischemic heart disease were at a higher risk for disease progression. We could not identify any atherosclerotic risk factors that reliably predicted patients in whom future ipsilateral neurologic symptoms were more likely to develop. However, there was an increased risk of stroke associated with progression of disease.

CONCLUSION

Patients who are asymptomatic and who have moderate carotid stenoses are at significant risk for neurologic symptoms and death, but have a relatively low incidence rate of ipsilateral events. The initial flow characteristics in the stenotic vessel are predictive of future disease progression, but they are not helpful in identifying patients in whom symptoms will develop.

Signalling pathway leading to an activation of mitogen-activated protein kinase by stimulating M3 muscarinic receptor

The signalling pathway leading to an activation of mitogen-activated protein (MAP) kinase subtypes Erk-1 and -2 upon stimulation of muscarinic receptor with carbachol in human neuroblastoma SK-N-BE2(C) cells was investigated. Carbachol activated Erk-1/-2 by stimulating M3 muscarinic receptor, as determined by specific antagonists for individual muscarinic receptors. The activation of Erk-1/-2 by carbachol was blocked by the inhibition or down-regulation of protein kinase C (PKC). Among the multiple PKC isoforms expressed in SK-N-BE2(C) cells, only PKCepsilon was activated by the treatment of carbachol, and selective down-regulation of PKCepsilon was sufficient to block Erk-1/-2 activation. Carbachol treatment induced activation of the serine/threonine protein kinase Raf, and an inhibition of Raf blocked Erk-1/-2 activation. Ectopic expression of inhibitory small GTPase Ras, RasN17, blocked the carbachol-induced Raf activation without affecting the activation of PKCepsilon, while the inhibition of PKC blocked the Raf activation. Thus, these results suggest that carbachol-induced activation of PKCepsilon mediates Erk-1/-2 activation by a sequential activation of Ras, Raf and MAP kinase kinase.

Prediction of facial nerve displacement in extra large vestibular schwannoma

The primary objective in the surgery of extra large vestibular schwannoma is the total removal of the tumour mass while preserving the facial nerve. Preservation of the facial nerve in extra large tumours is reported as being notoriously difficult in the majority of cases. This study was undertaken to evaluate the accuracy in predicting displacement of the facial nerve by preoperative radiological imaging studies in 19 cases of extra large vestibular schwannoma. The direction of displacement of the facial nerve was predicted with preoperative axial and coronal MRI scans and verified intraoperatively. We achieved total removal of tumours in 84.2%, facial nerve displacement was predicted in 80% and we accomplished anatomical preservation in 80%. Prediction of displacement was difficult in tumours with little or no intracanalicular components or with severe bony destruction of the internal acoustic meatus. The preoperative prediction of facial nerve displacement in extra large tumours allows safe internal decompression of the tumour and careful dissection near the predicted area of the facial nerve during the operation. Consequently, a high rate of anatomical preservation of the facial nerve can be achieved.

Relation of plasma homocyst(e)ine to cerebral infarction and cerebral atherosclerosis

BACKGROUND AND PURPOSE

A number of investigations support the theory that the elevated plasma homocyst(e)ine is associated with occlusive vascular disease. The aim of this study is to examine whether moderate hyperhomocyst(e)inemia is an independent risk factor for cerebral infarction. In addition, we examined the association between plasma homocyst(e)ine and the severity of cerebral atherosclerosis.

METHODS

We conducted a hospital-based case-control study with 140 male controls and 78 male patients with nonfatal cerebral infarction, aged between 39 and 82 years. Plasma homocyst(e)ine levels were analyzed in 218 subjects. Fifty-five patients were evaluated for cerebral vascular stenosis by MR angiography.

RESULTS

The mean plasma level of homocyst(e)ine was higher in cases than in controls (11.8+/-5.6 versus 9.6+/-4.1 micromol/L; P=0.002). The proportion of subjects with moderate hyperhomocyst(e)inemia was significantly higher in cases than in controls (16.7% versus 5.0%; P=0.004). Based on the logistic regression model, the odds ratio of the highest 5% of homocyst(e)ine levels in control group was 4.17 (95% confidence interval, 3.71 to 4. 71)(P=0.0001). After additional adjustment for total cholesterol, hypertension, smoking, diabetes, and age, the odds ratio was 1.70 (95% confidence interval, 1.48 to 1.95) (P=0.0001). The plasma homocyst(e)ine levels of patients having vessels with 3 or 2 stenosed sites were significantly higher than those of patients having vessels with 1 stenosed site or normal vessels (14.6+/-1.4, 11.0+/-1.4 versus 7.8+/-1.5, 8.9+/-1.4 micromol/L respectively; P<0. 02). Multiple logistic regression analysis revealed that moderate hyperhomocyst(e)ienemia was significantly associated with the number of stenosed vessels (P=0.001).

CONCLUSIONS

These findings suggest that moderate hyperhomocyst(e)inemia is an independent risk factor for cerebral infarction and may predict the severity of cerebral atherosclerosis in patients with cerebral infarction.

Noradrenergic neurotoxin suppresses gonadotropin-releasing hormone (GnRH) and GnRH receptor gene expression in ovariectomized and steroid-treated rats

The present study was designed to investigate whether noradrenergic neurotransmission regulates the gene expression of gonadotropin-releasing hormone (GnRH) in the preoptic area and GnRH receptor in the pituitary. To this end, N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4, 50 mg/kg), an intraperitoneal (i.p.) injection of selective noradrenergic neurotoxin, was administered 1 h before progesterone (1 mg) treatment in ovariectomized and estradiol-treated prepubertal rats. Treatment with DSP4 effectively blocked the progesterone-induced increase in hypothalamic noradrenaline content, but not dopamine content, indicating that DSP4 selectively inhibits noradrenergic neurotransmission. DSP4 significantly blocked progesterone-induced increase in serum luteinizing hormone (LH) concentrations as well as GnRH release from hypothalamic fragments incubated in vitro. DSP4 concomitantly down-regulated GnRH mRNA levels in the preoptic area, as determined by competitive reverse transcription-polymerase chain reaction. DSP4 also clearly down-regulated progesterone-induced GnRH receptor mRNA levels in the pituitary, whereas it failed to alter LHbeta mRNA levels. In summary, blockade of noradrenergic neurotransmission with DSP4 resulted in profound reductions of hypothalamic GnRH and pituitary GnRH receptor gene expression.

Acute effects of intermittent pneumatic compression on popliteal artery blood flow

OBJECTIVES

To investigate the immediate effects of intermittent pneumatic foot and calf compression (IPFCC) on popliteal artery blood flow in symptom-free volunteers and to determine the reproducibility of color flow duplex imaging in the popliteal artery.

DESIGN

Cohort study.

SETTING

A university associated tertiary care hospital.

PATIENTS

Forty lower limbs of 30 volunteers without symptoms or noteworthy risk factors of peripheral vascular disease.

INTERVENTIONS

Popliteal artery blood flow was measured in the sitting position before, during, and after the application of IPFCC using color flow duplex imaging. The interobserver, intraobserver, and between occasion within-subject variability of the popliteal artery blood flow were evaluated in 5 symptom-free volunteers who had at least 5 color flow duplex imaging measurements taken at each of the above time points on 3 different days.

MAIN OUTCOME MEASURES

The arterial diameter, peak systolic, end diastolic, and reverse-flow velocities were measured, as well as the duration of forward flow during diastole before, during, and after IPFCC. The same variables were measured in 5 separate volunteers by 3 different observers, on 3 separate days, at 3 separate times to determine reproducibility.

RESULTS

Including all types of variability, the popliteal artery blood flow varied from 8% to 39% with a mean value of 19%. Since the diameter of the artery was obtained with less than 5% variability, the time average mean velocity was responsible for the high variation in flow. During application of the IPFCC, the popliteal artery blood flow increased significantly in all subjects (P<.001). The mean increase in the flow was 2.4 times the baseline values. The diameter of the arteries remained unchanged while the time average velocity increased significantly (P<.001). This velocity increase was due to marked elevation in the peak systolic and end diastolic velocities and diminution of the reverse-flow component, as well as a prolongation of the forward flow during diastole. After cessation of the pump, flow returned to baseline levels (P=.41)

CONCLUSIONS

Ultrasound-derived popliteal artery blood flow measurements show moderate variability. The application of IPFCC greatly enhances popliteal artery blood flow. The flow increase is due to a dramatic drop in the peripheral vascular resistance as the peak systolic and end diastolic flow velocities increase and the reverse-flow component diminishes. Its role in the treatment of lower extremity occlusive arterial disease needs to be determined.

Modulation of MAP kinase signaling and growth characteristics by the overexpression of protein kinase C in NIH3T3 cells

This study was performed to examine effects of the overexpression of protein kinase C (PKC) isoforms (i.e., beta I, beta II, gamma, delta, eta, and zeta) on mitogen-activated protein (MAP) kinase (Erk-1 and -2) signaling and growth characteristics of NIH3T3 cells. Phorbol ester (PMA) activated endogenous and ectopically expressed PKC alpha, beta I, beta II, gamma, delta, epsilon, and eta. Overexpression of the examined PKC isoforms enhanced PMA-induced MAP kinase activation. Potentiation of MAP kinase activation was also observed upon stimulation of cells with platelet-derived growth factor (PDGF) although there was no indication for the activation PKC isoforms by PDGF. Inhibition of PKC blocked PMA- but not PDGF-induced MAP kinase activation. Thus, potentiation of PDGF-induced MAP kinase activation appears to be independent to PKC activity, while PMA-induced MAP kinase activation requires PKC activity. The ability of PKC isoforms to potentiate MAP kinase activation is not related to the growth characteristics of cells because individual PKC isoforms differentially regulated maximum density and proliferation of cells.

Amentoflavone, a plant biflavone: a new potential anti-inflammatory agent

Biflavonoid is one of unique classes of naturally-occurring bioflavonoids. Certain biflavonoids including amentoflavone were previously reported to have inhibitory effect on the group II phospholipase A2 activity. Amentoflavone was also found to inhibit cyclooxygenase from guinea-pig epidermis without affecting lipoxygenase. In this study, anti-inflammatory and analgesic activities of amentoflavone were evaluated. When amentoflavone was administered intraperitoneally, it showed a potent anti-inflammatory activity as determined by amelioration of croton-oil induced mouse ear edema. It also showed a potent anti-inflammatory activity in the rat carrageenan paw edema model (ED50 = 42 mg/kg) compared to the activity of prednisolone (35 mg/kg) and indomethacin (10 mg/kg). However, amentoflavone did not show a significant inhibitory activity against rat adjuvant-induced arthritis, a chronic inflammatory model. In addition, amentoflavone was found to possess a potent analgesic activity in the acetic acid writhing test (ED50 = 9.6 mg/kg) compared to the activity of indomethacin (3.8 mg/kg). These results suggest that amentoflavone may be a potential lead for a new type of anti-inflammatory agents having dual inhibitory activity of group II phospholipase A2 and cyclooxygenase.

Vitexicarpin, a flavonoid from the fruits of Vitex rotundifolia, inhibits mouse lymphocyte proliferation and growth of cell lines in vitro

Certain flavonoids having a C-2,3-double bond were reported to show an inhibitory activity against T-lymphocyte proliferation, but not against B-lymphocyte proliferation in vitro. In the course of these studies, vitexicarpin (3',5-dihydroxy-3,4',6,7-tetramethoxyflavone) isolated from the fruits of Vitex rotundifolia was found to show potent inhibition against lymphocyte proliferation. Vitexicarpin inhibited T-lymphocyte proliferation as well as B-lymphocyte proliferation at > 0.1 microM. IC50's were approximately 0.7 microM both for T- and B-cell proliferation. The inhibitory activity of vitexicarpin was reversible. Vitexicarpin also inhibited the growth of certain cancer cell lines, EL-4 and P815.9 (IC50 = 0.25-0.3 microM). These results suggest that vitexicarpin may be a potential therapeutic agent involved in inflammatory/immunoregulatory disorders such as rheumatoid arthritis and lymphomas.

Compensatory arterial enlargement is a common pathobiologic response in early atherosclerosis

BACKGROUND

Human arteries are dynamic conduits that respond to different stimuli by remodeling their structure and size. Arterial dilatation has been shown to occur in moderate and advanced atherosclerosis in studies that evaluated only one artery, either coronary, carotid, or superficial femoral artery (SFA). The purpose of this study was to quantify and compare compensatory arterial enlargement throughout the peripheral vascular system in early atherosclerosis.

METHODS

Seventy-two patients (40 male, 32 female, mean age 67 +/- 12 years) underwent transcutaneous B-mode ultrasound imaging during routine examinations. Thirty-nine carotid, 19 aorta, 19 iliac, 23 common femoral (CFA), 21 SFA, and 23 popliteal arteries were longitudinally imaged. Eight healthy volunteers (6 male, 2 female, mean age 27 +/- 2.2 years) had the same arteries evaluated (n = 48). Internal diameter (ID) and external diameter (ED) were measured in disease-free areas and in paired adjacent areas exhibiting increased intima-media thickening (IMT) and small atherosclerotic plaques. The percent change in ID, ED, IMT, and plaque thickness were calculated.

RESULTS

There was no observed change in ID or ED in all arteries of the healthy volunteers. When compared with normal vessel segments, all arteries demonstrated a marked decrease in ID and increase in ED in areas of small, hemodynamically insignificant plaque. The aorta had a 6.00% +/- 1.92% increase in ED, which was significantly less than the percent increase in ED observed in carotid (8.14 +/- 4.5%. P = 0.05), CFA (9.73 +/- 3.54%, P = 0.0001), SFA (9.15 +/- 4.25%, P = 0.005), and popliteal arteries (9.67 +/- 4.34, P = 0.002). In all arteries there was a strong correlation between plaque thickness and percent change in ED with the best correlation observed in the popliteal artery (R2 = 0.823, P < 0.0001). IMT was significantly increased in all normal vessel segments of the patients when compared with the healthy volunteers (P < 0.001).

CONCLUSION

All peripheral arteries dilate in response to intima-media thickening and early atherosclerotic plaque formation. This adaptive response occurs at the site of the lesion to preserve luminal area. The percent change in ED is strongly related to plaque thickness and is greatest in the more distal arteries.

Protein kinase C regulates chondrogenesis of mesenchymes via mitogen-activated protein kinase signaling

A possible regulatory mechanism of protein kinase C (PKC) in the chondrogenesis of chick limb bud mesenchymes has been investigated. Inhibition or down-regulation of PKC resulted in the activation of a mitogen-activated protein kinase subtype Erk-1 and the inhibition of chondrogenesis. On the other hand, inhibition of Erk-1 with PD98059 enhanced chondrogenesis and relieved PKC-induced blockage of chondrogenesis. Erk-1 inhibition, however, did not affect expression and subcellular distribution of PKC isoforms expressed in mesenchymes nor cell proliferation. The results suggest that PKC regulates chondrogenesis by modulating Erk-1 activity. Inhibition or depletion of PKC inhibited proliferation of chondrogenic competent cells, and Erk-1 inhibition did not affect PKC modulation of cell proliferation. However, PKC-induced modulation of expression of cell adhesion molecules involved in precartilage condensation was reversed by the inhibition of Erk-1. Expression of N-cadherin was detected at the early period of chondrogenesis. Inhibition or depletion of PKC induced sustained expression of N-cadherin, and Erk-1 inhibition blocked the effects of PKC modulation. The expression of integrin alpha5 beta1 and fibronectin was found to be increased transiently during chondrogenesis. Depletion or inhibition of PKC caused a continuous increase of the expression of these molecules throughout the culture period, and Erk-1 inhibition abolished the modulating effects of PKC. Because reduction of the examined cell adhesion molecule expression is a prerequisite for the progression of chondrogenesis after cell condensation, our results indicate that PKC regulates chondrogenesis by modulating expression of these molecules via Erk-1 signaling.

Regulation of chondrogenic differentiation of mesenchymes by protein kinase C alpha

Chondrogenesis of chick limb bud mesenchymes requires the expression and activation of protein kinase C (PKC). This study was performed to identify PKC isoform(s) involved in the regulation chondrogenic differentiation of mesenchymes. Multiple PKC isoforms including alpha, epsilon, zeta and lambda/iota were expressed in mesenchymes derived from chick limb buds. Among the expressed PKC isoforms, the levels of PKC alpha and epsilon were increased during chondrogenic differentiation of mesenchymes. The increase in the expression of these isoforms is more evident in the particulate membrane fraction compared with the cytosolic fraction. Chondrogenesis was blocked by either selective inhibition or down-regulation of PKC alpha. In addition, the degree of chondrogenesis was closely correlated with the expression levels of PKC alpha but not other PKC isoforms expressed in mesenchymes. Thus, the results indicate that only PKC alpha is required for the induction of chondrogenic differentiation

Percutaneous ultrasound guided thrombin injection: a new method for treating postcatheterization femoral pseudoaneurysms

PURPOSE

Since its introduction in 1991, ultrasound guided compression repair of postcatheterization femoral artery pseudoaneurysms has been shown to be effective. Disadvantages of ultrasound guided compression repair include patient discomfort during compression, inability to treat noncompressible pseudoaneurysms, prolonged use of ultrasound equipment and personnel, limited success with patients being treated with anticoagulants, and some early recurrences. We conducted a prospective study to evaluate a new method of treating femoral pseudoaneurysms, percutaneous ultrasound guided thrombin injection.

METHODS

Under duplex ultrasound guidance, a 22- or 25-gauge needle was percutaneously positioned within the pseudoaneurysm. Without compressing the pseudoaneurysm, 0.5 to 1 ml thrombin solution (1000 U/ml) was injected to induce thrombosis. Early in the study, the procedure was modified to allow more than one injection. After successful thrombosis, the patients were kept at rest in bed for at least 1 hour. Duplex ultrasound examination was repeated in 1 to 4 days. Distal pulses and ankle-brachial indexes were measured before and after the procedure.

RESULTS

Twenty of 21 consecutive pseudoaneurysms were successfully treated with thrombin injection. Fifteen pseudoaneurysms thrombosed immediately (<20 seconds) after one injection. The other five had partial thrombosis after one injection and complete thrombosis immediately after a second injection. The one failure occurred in a patient who had only one injection and then underwent subsequent ultrasound guided compression repair, which failed. No patient required sedation or analgesia during thrombin injection. There were no procedure-related complications and no recurrences.

CONCLUSIONS

Percutaneous ultrasound guided thrombin injection appears to be a safe and expeditious method for treating postcatheterization femoral pseudoaneurysms. It has significant advantages with respect to ultrasound guided compression repair or surgical repair.

Reynosin from Sassurea lappa as inhibitor on CINC-1 induction in LPS-stimulated NRK-52E cells

An inhibitor on CINC-1 (cytokine-induced neutrophil chemoattractant-1) induction in LPS-stimulated rat kidney epithelioid NRK-52E cells was purified from the roots of Sassurea lappa Clarke, a herbal medicine used in Korean traditional prescriptions for gastric intestinal diseases by a variety of column chromatographic procedures. The inhibitor was identified as reynosin, a sesquiterpene lactone isolated and characterized previously from Ambrosia confertiflora DC., and Magnolia grandiflora L. Reynosin exhibited a dose-dependent inhibition on CINC-1 induction in LPS-stimulated NRK-52E cells, where 50% of inhibitory effect was shown at the concentration of about 1 microM.

The region of dopamine transporter encompassing the 3rd transmembrane domain is crucial for function

Bovine dopamine transporter (bDAT) shows relatively low dopamine (DA) uptake efficacy and scant MPP+ transport and cocaine binding, while all of these activities are avid in human dopamine transporter (hDAT). In this study, we constructed a series of chimeras between human and bovine DAT to find out the structure(s) responsible for each DAT functions. DA uptake, MPP+ uptake, and cocaine binding in hDAT nearly disappeared only by the substitution of the 3rd transmembrane domain (TMD) with that of bDAT. On the contrary, the substitution of an identical region of hDAT into bDAT produced a complete shift toward the value of WT hDAT in the DA uptake, even though the MPP+ uptake and CFT binding maintained the values of WT bDAT. Collectively, these results suggest that the 3rd TMD in DAT is crucial for the function, especially for DA uptake.

Cytotoxic constituents of Saussurea lappa

The crude extract of Saussurea lappa displayed significant lethality to brine shrimp larvae. Investigation of the causative components by bioactivity-directed fractionation resulted in the isolation of three C17-polyene alcohols. Based on various nmr spectral data, these compounds were identified as shikokiols which had been previously isolated from Cirsium nipponicum and/or Centaurea aegyptica. These C17-polyene alcohols exhibited moderate cytotoxicities against the human tumor cell lines, A549, SK-OV-3, SK-MEL-2, XF498, and HCT15.

Fibroblast growth factor-2-toxin induced cytotoxicity: differential sensitivity of co-cultured vascular smooth muscle cells and endothelial cells

Recombinant FGF-2-SAP is a mitotoxin consisting of the plant-derived ribosome-inactivating toxin saporin (SAP) fused to basic fibroblast growth factor (FGF-2). FGF-2-SAP targets and kills cells bearing upregulated FGF receptors. In vivo, FGF-2-SAP inhibits smooth muscle cell hyperplasia in models of restenosis. The present study examined the potential for a differential effect of FGF-2-SAP on canine vascular endothelial cells (EC) and smooth muscle cells (SMC) separately as well as in a novel co-culture model. Canine vascular SMC and EC cultures were established separately and made quiescent once cells reached 80% confluence. Following the release from growth arrest, both cell types were treated with FGF-2-SAP, or FGF-2, or SAP alone for 48 h. [3H]TdR incorporation was used to determine the growth response of SMC and EC. The co-culture system was created by plating canine vascular SMC and EC on either side of a microporous 13 microm thick polyester membrane insert. Both cell types were grown to 80% confluence and independently made quiescent. Following the release from growth arrest, cells were treated with FGF-2-SAP, or FGF-2, or SAP alone. Negative and positive control groups were untreated wells containing phosphate buffered saline and complete growth media, respectively. After 48 h, both [3H]TdR incorporation and total DNA content, by fluorometric measurement, were quantitated in SMC and EC independently. FGF-2-SAP showed a concentration-dependent cytotoxicity in both canine SMC and EC but cytotoxicity for EC required substantially higher concentrations. In co-cultured SMC, FGF-2-SAP significantly decreased both [3H]TdR uptake and total DNA content at 0.5, 5, 50, and 500 ng/ml (0.01-10 nM) compared to positive controls. In co-cultured EC, FGF-2-SAP decreased [3H]TdR uptake at 50 and 500 ng/ml and total DNA content at 500 ng/ml compared to positive controls. Neither SAP alone nor FGF-2 alone showed a significant effect on [3H]TdR uptake or DNA content of either SMC or EC. In this unique co-culture model, which better replicates the relationship between SMC and EC in vivo, we demonstrated a dose-response range of FGF-2-SAP at which both the proliferation and total cell number of SMC, but not EC, is significantly reduced. These data suggest that FGF-2-SAP may have therapeutic utility in inhibiting myointimal hyperplasia in the absence of a deleterious effect on regenerating endothelium following vascular reconstructions.

Production of inducible nitric oxide is required for monocytic differentiation of U937 cells induced by vitamin E-succinate

Many putative differentiating agents arrest cell growth prior to progression of the cell through differentiation. Vitamin E-succinate is known to be a potent modulator of haematopoietic differentiation as well as an inhibitor of cell growth in vitro and in vivo. In this study, we examined whether vitamin E-succinate could modulate the monocytic differentiation of U937 human monoblasts. Treatment with vitamin E-succinate for 1–4 days inhibited the proliferation of U937 cells. Vitamin E-succinate also induced monocytic differentiation as indicated by the increase in nitro blue tetrazolium reduction activity, and the expression of monocyte specific cell surface antigen, CD11c, and integrins alpha5 and beta1. The monocytic differentiation of U937 cells was also induced when the cells were cultured in fibronectin-coated wells. Monocytic differentiation was enhanced when the cells were treated with both vitamin E-succinate and fibronectin, suggesting that vitamin E-succinate and fibronectin synergistically act on monocytic differentiation of U937 cells. During monocytic differentiation of U937 cells induced by vitamin E-succinate and/or fibronectin, nitric oxide was detected in supernatants. The production of nitric oxide was not detected when monocytic differentiation of U937 cells was induced by phorbol-12 myristate 13-acetate, a well known inducer of macrophage-like cell differentiation. Vitamin E-succinate and/or fibronectin induced monocytic differentiation was blocked by the treatment of nitric oxide synthase inhibitor, N-G-monomethyl-L-arginine. In contrast, treatment of cells with sodium nitroprusside, a chemical nitric oxide donor, stimulated monocytic differentiation of U937 cells at an early time point. Taken together, these results suggest that nitric oxide is an important intermediator at an early stage of vitamin E-succinate- and/or fibronectin-induced monocytic differentiation of U937 cells.

Lathyrus saponin, a new trisaccharide glycoside from Lathyrus japonicus

A new triterpenoid saponin, named Lathyrus saponin (3), was isolated from the whole plant of Lathyrus japonicus Willd. together with two known saponins, azukisaponins II (1) and V (2). as their methyl esters. The structure of 3 was determined to be soyasapogenol B 3-0-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glu curonopyranoside on the basis of physicochemical and spectroscopic methods.

Differential regulation of gonadotropin-releasing hormone (GnRH) receptor expression in the posterior mediobasal hypothalamus by steroid hormones: implication of GnRH neuronal activity

The present study is designed to evaluate the relationship between gonadotropin-releasing hormone (GnRH) and GnRH receptor (GnRHR) gene expression during the steroid-induced LH surge. One week after ovariectomy (OVX), a capsule containing 17beta-estradiol (E) or vehicle (V) was implanted into OVX rats, and 2 days later a single injection of progesterone (P) or V was administered s.c. at 10:00 h. Poly(A)-rich RNA samples were isolated from the micropunches of the preoptic area (POA) and the posterior mediobasal hypothalamus (pMBH) from both sides of individual brain slices. Using competitive reverse transcription-polymerase chain reaction (RT-PCR) procedures, three parameters (POA GnRH, pMBH GnRHR) and pituitary GnRHR mRNA levels were simultaneously determined in each individual animal. POA GnRH mRNA and pituitary GnRHR mRNA levels were decreased by treatment with E, but increased by a combination of E and P. In contrast, pMBH GnRHR mRNA levels were clearly augmented by treatment with E, and decreased by the combination of E and P. Temporal changes in such parameters were determined in OVX+E+V- and OVX+E+P-treated rats. P augmented POA GnRH mRNA levels at the time of the LH surge (17:00 h) and the increased GnRH mRNA levels were remained until 22:00 h, while E alone failed to alter POA GnRH mRNA levels. In the pMBH micropunch samples, P substantially decreased E-induced increase in GnRHR mRNA levels at 17:00 h and further lowered those until 22:00 h. Antisense oligonucleotides of GnRHR mRNA administered into the lateral ventricle of OVX+E-treated rats blocked the E-induced increase in pMBH GnRHR mRNA levels. The antisense oligonucleotides also prevented the LH surge as well as the increase in pituitary GnRHR mRNA levels in the OVX+E+P-treated group. However, administration of this antisense oligonucleotides failed to alter POA GnRH mRNA levels. In conclusion, the present study demonstrated that there is an inverse relationship between POA GnRH mRNA levels and pMBH GnRHR mRNA levels in response to E and/or P, and that the blockade of the E-induced increase in pMBH GnRHR mRNA levels effectively nullified the P-induced LH surge. These results indicate that pMBH GnRHR gene expression is involved in synchronizing the GnRH neuronal activity, which is crucial for the generation of the LH surge.

C/EBP alpha and C/EBPbeta play similar roles in the transcription of the human Cu/Zn SOD gene

Copper/zinc-containing superoxide dismutase (Cu/Zn SOD) is one of the essential enzymes that protects cells in aerobic conditions. To understand the mechanism of transcriptional regulation of the human Cu/Zn SOD gene, the proximal promoter region of Cu/Zn SOD has been investigated. In a previous study, it was found that transcription factors of the Sp1 and C/EBP family are associated with the expression of human Cu/Zn SOD [Seo et al. (1996). Gene, 178, 177-180]. Of the four known C/EBP activators, the effects of C/EBP alpha and C/EBPbeta on the transcription of Cu/Zn SOD were examined. Usually, one of the two C/EBP factors, C/EBP alpha or C/EBPbeta, exclusively stimulates the target gene, but, unexpectedly, C/EBP alpha and C/EBPbeta stimulated the expression of Cu/Zn SOD to a similar extent in our experiments. LIP, a dominant negative regulator of the C/EBP family, inhibited the transcriptional activation of Cu/Zn SOD stimulated by C/EBP alpha and C/EBPbeta. These results suggest that C/EBP alpha and C/EBPbeta can substitute each other and play similar roles on the transcription of Cu/Zn SOD.

Prevalence and clinical significance of posterolateral thigh perforator vein incompetence

PURPOSE

Posterolateral thigh perforator (PLTP) veins are part of the lateral thigh venous system, which in most people remains undeveloped. This study was designed to determine the prevalence and clinical significance of these veins.

METHODS

Over the past 6 years, 2820 lower limbs with signs and symptoms of chronic venous disease (CVD) were evaluated for venous reflux using color flow duplex imaging. Superficial, perforating, and deep veins were examined in the standing, sitting, and reversed Trendelenburg positions. PLTP veins were best identified in the standing position with the patient facing away from the examiner.

RESULTS

Twenty-six incompetent PLTP veins were found in 24 limbs (0.85%) of 21 patients (mean age, 43 +/- 16 years; range, 22 to 77 years). All PLTP veins pierced the fascia lata 12 to 25 cm (mean, 16 +/- 3 cm) above the popliteal skin crease in the lateral aspect of the thigh. At this level, the PLTP veins dove posteriorly 3 to 8 cm to join primarily tributaries of the deep femoral vein, superficial femoral vein, or both. Eight PLTP veins were duplicated at 1 to 2 cm below the fascia. Seven PLTP veins gave rise to superficial tributaries that were extended to the lower lateral and posterior thigh, whereas the remaining 19 PLTP veins gave rise to tributaries alongside the lesser saphenous vein and the anterior arch of the greater saphenous vein. On nine occasions, reflux was found in the PLTP veins and their associated tributaries alone. In all of these cases, reflux was adequately controlled with a tourniquet placed distal to the fascial defect. In the remaining 17 PLTP veins, reflux was also seen in the greater saphenous vein, the lesser saphenous vein, or both. None of the limbs that had PLTP vein reflux alone exceeded CVD class 3. When PLTP vein reflux was combined with saphenous reflux, there were five limbs classified as CVD class 4 and one limb each as CVD classes 5 and 6. Twenty limbs underwent ligation and stripping of the varicosities. Three of the earlier patients in the series underwent incomplete operations, which resulted in immediate residual varicosities from the PLTP tributaries. All three patients underwent reoperation successfully within a year.

CONCLUSIONS

The prevalence of PLTP vein reflux is quite low. Reflux in the PLTP veins alone is associated with mild to moderate clinical presentation. However, when it is combined with saphenous reflux skin damage can be present. Failure to recognize PLTP veins may result in an incomplete or unnecessary operation, leaving the patients with residual varicose veins.

Where does venous reflux start?

PURPOSE

This study was designed to identify the origin of lower limb primary venous reflux in asymptomatic young individuals and to compare patterns of reflux with age-matched subjects with prominent or clinically apparent varicose veins.

METHODS

Forty age- and sex-matched subjects with no symptoms (age, 15 to 35 years; 80 limbs; group A), 20 subjects (age, 19 to 32 years; 40 limbs) with prominent but nonvaricose veins (n = 26 limbs; group B), and 50 patients (age, 17 to 34 years; 100 limbs) with varicose veins (n = 64; group C) were examined with color flow duplex imaging. All proximal veins (above popliteal skin crease), superficial, perforator, and deep, in the lower limb were examined in the standing position, and all the distal veins in the sitting position. Patients who had a documented episode of superficial or deep vein thrombosis, previous venous surgery, or injection sclerotherapy were excluded from the study.

RESULTS

The prevalence of reflux in group A was 14% (11 of 80), in group B 77% (31 of 40), and in group C 87% (87 of 100). In more than 80% of limbs in the three groups, reflux was confined to the superficial veins alone. Deep venous reflux or combined patterns of reflux were uncommon even in group C. Reflux was detected in all segments of the saphenous veins and their tributaries. In the 125 limbs that had superficial venous incompetence, the below-knee segment of the greater saphenous vein was the most common site of reflux (85, 68%), followed by the above-knee segment of greater saphenous vein (69, 55%) and the saphenofemoral junction (41, 32%). Nonsaphenous reflux was rare (3, 2.4%). Reflux in the lesser saphenous vein (21, 17%) was seen in all groups, whereas involvement of both greater and lesser saphenous veins (8, 6.4%) was seen in group C alone. The incidence of multisegmental reflux was significantly higher in group C (61 of 64, 95%) than in group A (two of 11, 18%) or group B (14 of 26, 54%). The prevalence of distal reflux was comparable in all groups.

CONCLUSIONS

Primary venous reflux can occur in any superficial or deep vein of the lower limbs. The below-knee veins are often involved in asymptomatic individuals and in those who have prominent or varicose veins. These data suggest that reflux appears to be a local or multifocal process in addition to or separate from a retrograde process.

A triterpenoid saponin from Patrinia scabiosaefolia

A new triterpenoid saponin, patrinia saponin H3 (3), was isolated from the aerial parts of Patrinia scabiosaefolia Fisch. and determined to be 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-rhamnopyranosyl (1-->2)-alpha-L-arabinopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ester on the basis of NMR and FAB MS experiments and acid hydrolysis.

Cytogenetic abnormalities related to histopathologic grade of astrocytic tumors

Cytogenetic analysis was performed on 7 low-grade astrocytomas, 10 anaplastic astrocytomas, and 14 glioblastomas. Abnormal chromosome numbers were noted in all cases of high-grade astrocytomas but were rarely noted in low-grade astrocytomas (28%). The most consistent changes in high-grade astrocytomas were complete loss of chromosome 10 (61%), gain of chromosome 7 (56%), and loss of chromosome 17 (28%). Certain structural abnormalities, such as marker chromosomes and double minutes (33%), and the deletion and translocation of chromosomes 1 (33%) and 17 (17%), were also noted. These results indicate that changes in the number and/or structure of chromosomes with related inactivation of tumor suppressor gene or oncogene activation might play a critical role in the formation and anaplastic progression of astrocytic tumors.

Modification of the Greenwood formula for correlated response times

Life-table methodology for interval-censored survival times is used to estimate marginal survival probabilities from data consisting of independent cohorts of correlated responses. We restrict our attention to situations where response times within cohorts are exchangeable and the marginal survival distributions are the same for all individuals within any cohort. A modification of the Greenwood formula is derived for estimating variances and covariances of the estimates of the marginal survival probabilities. Simulation results show that this formula provides accurate adjustments for within-cohort correlations in finite samples. Comparisons with a nonparametric maximum likelihood estimator indicate negligible loss in efficiency from using simple life-table estimators of marginal survival probabilities that ignore the within-cohort correlations. Data from an angioplasty study where more than one procedure is performed on some patients are used to illustrate this methodology.

Phorbol ester effects in atypical protein kinase C zeta overexpressing NIH3T3 cells: possible evidence for crosstalk between protein kinase C isoforms

To examine whether multiple protein kinase C (PKC) isoforms could interact or crosstalk, phorbol ester-insensitive atypical PKC (aPKC) zeta isoform was overexpressed in NIH3T3 cells, and the cells were stimulated with phorbol ester to activate diacylglycerol-dependent conventional (cPKC) and novel PKC (nPKC) isoforms. Treatment of cells with phorbol ester which activates PKCalpha, gamma, delta, and epsilon isoforms in NIH3T3 cells significantly reduced proliferation of cells. Overexpression of aPKCzeta and subsequent phorbol ester treatment abolished phorbol ester-induced reduction in cell proliferation. Overexpression of aPKCzeta also potentiated phorbol ester-induced mitogen-activated protein (MAP) kinase activation in a PKC-dependent manner. The effects of PKCzeta overexpression on proliferation and MAP kinase activation were proportional to the levels of aPKCzeta expression. Since aPKCzeta cannot be activated by phorbol ester, modulation of cell proliferation and MAP kinase activation by phorbol ester in aPKCzeta overexpressing cells might be due to the activation of cPKCs and/or nPKCs by phorbol ester. Thus, the results provide possible evidence for either direct or indirect crosstalk between PKC isoforms.

Seasonal variation of skin reactivity and specific IgE antibody to house dust mite

BACKGROUND

House dust mite is an important cause of bronchial asthma worldwide. While the allergen is present all year-round, a seasonal variation of house dust mite allergen levels has been found. There have been few reports, however, on seasonal variation of specific immune response to house dust mite.

OBJECTIVE

We studied the changes in skin reactivity and specific IgE antibody to house dust mite associated with seasonal variation of house dust mite allergen levels in houses of mite-sensitive asthmatic patients.

METHODS

In 14 mite-sensitive asthmatic patients, house dust mite allergen (Der f 1) contents in bedding were measured monthly. Skin reactivity on prick test and specific IgE antibody to house dust mite, Dermatophagoides farinae (D. farinae), were determined every 3 months from july to December.

RESULTS

The concentration of Der f 1 in dust from bedding reached maximum levels in August and September, and significantly decreased in November and December compared with August and September (P < .05). Skin reactivity (a ratio of mean wheal diameter of allergen to histamine) to D. farinae decreased significantly in December compared with September (P < .05). Serum levels of total IgE and specific IgE antibody to D. farinae decreased significantly in December compared with September (P < .05).

CONCLUSION

These findings suggest that seasonal changes in natural exposure to house dust mite allergen might lead to concurrent changes in skin reactivity and specific IgE antibody to house dust mite in mite-sensitive asthmatic patients.

Carotid endarterectomy for recurrent stenosis

PURPOSE

The purpose of this study was to report our results in the surgical management of recurrent carotid stenosis (RCS) after carotid endarterectomy (CEA).

METHODS

In a 20-year period, we performed 1209 CEAs; 82 operations (6.8%) were for RCS. There were 33 men and 36 women, with an average age of 66.3 years. Nine patients underwent two redo CEAs and two patients underwent three redo CEAs for either bilateral recurrence or a second recurrence on the same side. Overall, 10 patients were identified with a second recurrence.

RESULTS

The average time to presentation with RCS was 65 months (range, 3 to 361 months). The majority of patients (66%) were symptomatic, 34% had transient ischemic attacks, 17% had amaurosis fugax, 9% had strokes, and 6% had nonhemispheric symptoms. Before repair, angiograms were obtained. Patch repair was performed in 61 procedures (74%), 41 with vein, 11 with Dacron, and nine with polytetrafluoroethylene. Autogenous or synthetic bypass grafts were used in 20 procedures (24%), vein in eight, Dacron in two, and polytetrafluoroethylene in 10. In one patient, an occluded internal carotid artery was ligated and an endarterectomy of the external carotid artery was performed without a patch. The operative stroke rate was 4.8%. Minor complications included transient or permanent cranial nerve deficits in 7.3% and wound hematomas in 2.4%.

CONCLUSION

Although repeat endarterectomy to treat RCS is technically more demanding, it can be performed safely. Long-term follow-up examination shows that a second recurrence may develop, and we recommend serial noninvasive testing.

Effects of albumin coating of knitted Dacron grafts on transinterstitial blood loss and tissue ingrowth and incorporation

Transinterstitial blood loss at implantation and the degree of graft incorporation and inner capsule thickening was compared in serial explants of albumin-coated Dacron versus blood preclotted Dacron grafts in the canine thoracoabdominal aortic position (8 mm internal diameter x 30 cm length). The coated grafts were Bard DeBakey Vasculour II knitted Dacron prostheses impregnated with carbodiimide-cross-linked human albumin. Control grafts were otherwise identical and preclotted with the recipients' whole blood before heparinization during surgery. Transinterstitial blood loss after establishing flow was measured by weighing sponges wrapped around the grafts. Albumin pretreatment resulted in significantly less median blood loss (5.1 g versus 11 g, P=0.04; Mann-Whitney rank sum test). Grafts were explanted at 1 week, 4 weeks, 10 weeks, and 20 weeks. Patency was 100% in both groups. Graft incorporation at explantation was graded by the surgeon as: 1 = none, 2 = minimal, 3 = moderate, or 4 = extensive. No significant differences were noted at any time period. Inner capsule thickness measurements were made every 2.5 mm along the length of all explants. Grafts explanted at 1 week displayed no inner capsules. By 20 weeks, median inner capsule thickness was significantly less in albumin-coated grafts (190 microm versus 235 microm; P<0.0001). These inner capsules in both groups formed as islands, containing abundant myofibroblasts and collagen, covered by endothelial cells and surrounded by residual fibrin coagula. In conclusion, albumin-coated knitted Dacron grafts displayed less transinterstitial blood loss at implantation, and qualitatively similar incorporation, but significantly thinner inner capsules at 20 weeks.

Cortisol and estradiol: nongenetic factors for hyperhomocyst(e)inemia

A low plasma homocyst(e)ine concentration in premenopausal and pregnant women compared with postmenopausal women and men suggests that steroid hormones are nongenetic factors affecting homocysteine metabolism. This hypothesis was tested by determining plasma homocyst(e)ine levels in adult male rats treated with cortisol, estradiol, or a combination of both. Mean plasma homocyst(e)ine concentrations were 3.71 +/- 0.71, 5.26 +/- 1.76, and 4.28 +/- 0.84 nmol/mL in cortisol-treated, estradiol-treated, and cortisol plus estradiol-treated groups, respectively. These values were substantially low compared with the level of 7.32 +/- 0.89 nmol/mL plasma homocyst(e)ine in the control group, indicating a significant effect of steroid hormones on homocysteine metabolism.

In vitro antimutagenic effects of anthraquinone aglycones and naphthopyrone glycosides from Cassia tora

The antimutagenic activity of a methanol extract of Cassia tora seeds against aflatoxin B1(AFB1) was demonstrated with the Salmonella typhimurium assay. The numbers of revertants per plate decreased significantly when this extract was added to the assay system using Salmonella typhimurium TA100 and/or TA98. The MeOH extract was then sequentially partitioned with CH2Cl2, n-BuOH and H2O. The CH2Cl2 and n-BuOH fractions possessed antimutagenic activity but the H2O fraction was inactive. Neither the MeOH extract nor its fractions were capable of inhibiting the direct-acting mutagen N-methyl-N'-nitro-N-nitrosoguanidine suggesting that these fractions may prevent the metabolic activation of AFB1 or scavenge the electrophilic intermediate capable of inducing mutations. Column chromatography using silica gel yielded pure chrysophanol, chryso-obtusin, and aurantio-obtusin from the CH2Cl2 fraction and cassiaside and rubro-fusarin gentiobioside from the n-BuOH fraction. Each of these compounds demonstrated significant antimutagenic activity.

Novel anticholinesterase and antiamnesic activities of dehydroevodiamine, a constituent of Evodia rutaecarpa

To find a new compound with antiamnesic activity, we screened 29 natural products for their abilities to inhibit acetylcholinesterase and reverse scopolamine-induced amnesia. Among the plants tested Evodia rutaecarpa Bentham showed a strong inhibitory effect on acetylcholinesterase in vitro and an anti-amnesic effect in vivo. By sequential fractionation of E. rutaecarpa, the active component was finally identified as dehydroevodiamine hydrochloride (DHED). DHED inhibited acetylcholinesterase activity in a dose-dependent and non-competitive manner. The IC50 value of DHED is 37.8 microM. A single administration of DHED to rats (6.25 mg/kg) significantly reversed the scopolamine-induced memory impairment in a passive avoidance test. The antiamnesic effect of DHED was more potent than that of tacrine which is the only drug for Alzheimer's disease approved by FDA. This potent antiamnesic effect of DHED was thought to be due to the combined effects of acetylcholinesterase inhibition and the known cerebral blood flow enhancement. These results indicate that DHED has novel anti-cholinesterase and antiamnesic activities and might have therapeutic potential in various disorders including Alzheimer's disease.

The cytotoxicity of psoralidin from Psoralea corylifolia

A cytotoxic coumestan derivative, psoralidin (1), was isolated from the seed of Psoralea corylifolia. The IC50 values of 1 against SNU-1 and SNU-16 carcinoma cell lines were 53 and 203 micrograms/ml, respectively, indicating cytotoxic activity against stomach carcinoma cell lines.

Diacylglycerylgalactosides from Arisaema amurense

Previously undescribed 1,2-O-diacyl-3-O-beta-D-galactopyranosyl glycerols and 1,2-O-diacyl-3-O-[alpha-D-galactopyranosyl-(1"-->6')-O-beta-D- galactopyranosyl] glycerols were isolated as single components from Arisaema amurense. The cytotoxicities of these compounds against P388 and DLD-1 are described.

Treatment of hyperhomocyst(e)inemia: physiological basis

Hyperhomocyst(e)inemia (HCY) is caused either by genetic or nongenetic defect(s), and the clinical severity of HCY is correlated with the biochemical abnormality. Treatment of HCY is approached on the basis of its etiology and severity of defect. The preferred method of treatment for genetic HCY is activation of mutant enzyme activity with the cofactor or the precursor of cofactor. If HCY does not respond to this treatment, pharmacological doses of betaine or folic acid should be used to enhance the alternative pathway of homocysteine turnover. Phenotypic expression of minor genetic defects, such as heterozygous cystathionine synthase deficiency and thermolabile methylenetetrahydrofolate reductase (MTHFR) can be amplified or masked by nongenetic (nutritional) factor(s). Hence, supplementation of folic acid, vitamin B-12, pyridoxine and choline to maintain their serum concentrations above low normal range may satisfactorily prevent the development of moderate HCY due to a minor genetic defect.