Hemovac blood after total knee arthroplasty as a source of stem cells

Background

With increasing life expectancy, stem cell therapy is receiving increasing attention. However, its application is restricted by ethical concerns. Hence a need exists for design of safe procedures for stem cell procurement. Here, we investigated whether hemovac blood (HVB) is an appropriate stem cell source.

Methods

HVB concentrates (HVBCs) from 20 total knee arthroplasty (TKA) patients and bone marrow aspirate (BMA) concentrates (BMACs) from 15 patients who underwent knee cartilage repair were comparatively evaluated. A bone marrow aspiration needle was inserted into the anterior superior iliac spine. Aspiration was performed using a 50-mL syringe, including 4 mL of anticoagulant, followed by centrifugation to obtain BMACs. To obtain HVBCs, blood was aspirated from the hemovac immediately after TKA surgery. Different cell types were enumerated. Isolation of BMA and HVB mononuclear cells was performed using density gradient centrifugation. Non-hematopoietic fibroblast colonies were quantified by colony forming unit-fibroblast assay surface marker analysis of HVB, HVBC, BMA, and BMAC was performed via flow cytometry. Mesenchymal stem cells (MSCs) isolated from HVBCs and BMACs were examined for osteogenic, adipogenic, and chondrogenic differentiation potential. Gene expression analysis was performed by quantitative real-time polymerase chain reaction (qRT-PCR).

Results

The number of cells from HVB and HVBC was significantly lower than from BMA and BMAC; however, the number of colonies in HVBC and BMAC did not differ significantly (P>0.05). Isolated cells from both sources had a fibroblast-like appearance, adhered to culture flasks, and formed colonies. Under different culture conditions, MSC-specific surface markers (CD29, CD44, CD90, CD105), osteogenic markers [RUNX2, osteopontin, osteocalcin, and alkaline phosphatase (ALP)] and adipogenic markers (PPARγ and C/EBPα) were expressed. Moreover, SOX9, type II collagen, and aggrecan were significantly upregulated upon chondrogenic differentiation.

Conclusions

HVB from TKA patients is a useful source of stem cells for research.

Articular cartilage repair using autologous collagen-induced chondrogenesis (ACIC): a pragmatic and cost-effective enhancement of a traditional technique

PURPOSE

The autologous collagen-induced chondrogenesis technique is described, and the results of a 6-year follow-up clinical study using this technique are presented.

METHODS

30 patients with International Cartilage Repair Society (ICRS) Grade III/IVa symptomatic chondral defects of the knee treated with enhanced microdrilling using atelocollagen were prospectively examined in this clinical series. The median age of the patients was 39.0 years (range 19-61 years). Patients were followed up to 72 months. Clinical evaluation was performed using functional knee scores and radiologically. Both quantitative and qualitative assessments were performed.

RESULTS

Statistically significant and clinically relevant improvement was observed in 2 years and was sustained for the 6 years of the study observation. At 6 years, the mean Lysholm score was 79.7 (SD 6.8) compared to 52.6 (SD 10.7) pre-operatively (p < 0.05). The symptomatic Knee Injury and Osteoarthritis Outcome Score (KOOS) improved from 68.3 (SD 11.4) to 90.2 (SD 4.3) (p < 0.05). The subjective International Knee Documentation Committee (IKDC) also showed improvement from 39.1 (SD 4.1) to 81.6 (SD 7.8) (p  < 0.05). The calculated T2* relaxation times were 26.0 (SD 4.2) seconds and 30.3 (SD 6.2) seconds for the repair tissue and native cartilage, respectively. The average magnetic resonance observation of cartilage repair tissue (MOCART) score was 78.5 (SD 9.6) for all lesions.

CONCLUSION

The enhanced microdrilling using atelocollagen is an enhancement of the traditional microfracture method using an off-the-shelf product. When used to treat moderate to severe chondral lesions, this enhancement produces hyaline-like cartilage with a corresponding improvement in symptoms.

LEVEL OF EVIDENCE

IV.

Tibial tubercle avulsion fracture according to different mechanisms of injury in adolescents: Tibial tubercle avulsion fracture

Tibial tubercle avulsion fracture caused by knee extensor is very rare; furthermore, non-traumatic fractures during running or bilateral fractures have been reported. The purpose of this study was to evaluate any differences according to the mechanisms of injury in adolescents with tibial tubercle avulsion fracture.Thirty patients with tibial tubercle avulsion fractures were reviewed and the average age was 13 years 1 month. Seven patients (low-stress group) had a spontaneous fracture during running without definite trauma. Twenty-three patients (high-stress group) experienced pain during jumping and landing, or definite trauma. The mechanisms of injury, age, height, weight, body mass index (BMI), BMI percentile, fracture type, as well as any complication, such as limitation of motion and deformity related to the physeal arrest, were compared between groups.There was no definite difference in age, fracture type, and surgical outcomes between groups. There was no patient with significant early physeal arrest in both groups. The weight (P = .02), BMI (P = .03) and BMI percentile (P = .01) in low-stress group were higher than those in high-stress group. In low-stress group, 6 patients' BMIs were in the 97th percentile, and 1 patient's BMI was in the 5th percentile.Extreme BMI may be a risk factor for tibial tubercle avulsion fractures in adolescents during running without definite trauma. However, there was no difference in the final outcome according to injury mechanisms.

Reliability of predictive models for non-operative healing potential of stable juvenile osteochondritis dissecans knee lesions

BACKGROUND

While juvenile osteochondritis dissecans (JOCD) lesions have greater healing potential than equivalent lesions in adults, only 50% of JOCD lesions demonstrate radiographic healing after six months of non-operative treatment. Two previous studies have produced nomograms to predict a patient's probability of healing with non-operative treatment based on patient and lesion characteristics. The purpose of this study was to determine inter- and intra-observer reliability of the predictive nomograms.

METHODS

A consecutive series of 34 skeletally immature patients (40 knees), who underwent non-operative treatment for stable JOCD lesions was retrospectively reviewed. At two time points at least one week apart, two medical students, two orthopaedic surgeons, and a radiologist made measurements of the JOCD lesions. These measurements, along with patient ages and pain type, were used to generate a point value for each lesion based on both nomograms. Intra-class correlations (ICCs) were calculated to determine inter- and intra-rater reliability.

RESULTS

We found near perfect intra-rater correlation (ICC) for all raters' individual OCD measurements, as well as total point score for the two nomograms (ICC range, 0.780-0.929). Additionally, there was near perfect inter-rater reliability among raters for total scores and individual components of each nomogram (ICC range, 0.721-0.974).

CONCLUSIONS

There is high inter- and intra-rater reliability for both point systems for predicting healing of JOCD lesions. Clinicians should be aware of these as tools to help guide decision making in patients with JOCD lesions.

Abatement of fluorinated compounds using a 2.45GHz microwave plasma torch with a reverse vortex plasma reactor

Abatement of fluorinated compounds (FCs) used in semiconductor and display industries has received an attention due to the increasingly stricter regulation on their emission. We have developed a 2.45GHz microwave plasma torch with reverse vortex reactor (RVR). In order to design a reverse vortex plasma reactor, we calculated a volume fraction and temperature distribution of discharge gas and waste gas in RVR by ANSYS CFX of computational fluid dynamics (CFD) simulation code. Abatement experiments have been performed with respect to SF6, NF3 by varying plasma power and N2 flow rates, and FCs concentration. Detailed experiments were conducted on the abatement of NF3 and SF6 in terms of destruction and removal efficiency (DRE) using Fourier transform infrared (FTIR). The DRE of 99.9% for NF3 was achieved without an additive gas at the N2 flow rate of 150 liter per minute (L/min) by applying a microwave power of 6kW with RVR. Also, a DRE of SF6 was 99.99% at the N2 flow rate of 60 L/min using an applied microwave power of 6kW. The performance of reverse vortex reactor increased about 43% of NF3 and 29% of SF6 abatements results definition by decomposition energy per liter more than conventional vortex reactor.

A comparative study of DA-9601 and misoprostol for prevention of NSAID-associated gastroduodenal injury in patients undergoing chronic NSAID treatment

Misoprostol is reported to prevent non-steroidal anti-inflammatory drug (NSAID)-associated gastroduodenal complications. There is, however, limited information regarding the efficacy of DA-9601 in this context. We performed a comparative study on the relative efficacy of DA-9601 and misoprostol for prevention of NSAID-associated complications. In this multicenter, double-blinded, active-controlled, stratified randomized, parallel group, non-inferiority trial, 520 patients who were to be treated with an NSAID (aceclofenac, 100 mg, twice daily) over a 4-week period were randomly assigned to groups for coincidental treatment with DA-9601 (60 mg, thrice daily) (236 patients for full analysis) or misoprostol (200 μg, thrice daily) (242 patients for full analysis). A total of 236 patients received DA-9601 and 242 received misoprostol. The primary endpoint was the gastric protection rate, and secondary endpoints were the duodenal protection rate and ulcer incidence rate. Endpoints were assessed by endoscopy after the 4-week treatment period. Drug-related adverse effects, including gastrointestinal (GI) symptoms, were also compared. At week 4, the gastric protection rates with DA-9601 and misoprostol were 81.4 % (192/236) and 89.3 % (216/242), respectively. The difference between the groups was −14.2 %, indicating non-inferiority of DA-9601 to misoprostol. Adverse event rates were not different between the two groups; however, the total scores for GI symptoms before and after administration were significantly lower in the DA-9601 group than in the misoprostol group (−0.2 ± 2.8 vs 1.2 ± 3.2; p < 0.0001). DA-9601 is as effective as misoprostol in preventing NSAID-associated gastroduodenal complications, and has a superior adverse GI effect profile.

Analysis of S gene mutation of the hepatitis B virus in adult liver transplant recipients showing resistance to hepatitis B immunoglobulin therapy

BACKGROUND

A considerable proportion of recipients of liver transplantations who are presented hepatitis B immunoglobulin (HBIG) monotherapy for hepatitis B virus (HBV) prophylaxis develop HBIG resistance. In this study, we investigated the mutation patterns in the major hydrophilic region (MHR) of amino acid sequences 100 to 160.

METHODS

Using the gene sequence analyzer for amino acid sequences 0 to 226 in the S/pre-S region we analyzed blood samples of 15 patients showing HBIG resistance after high-dose HBIG prophylaxis.

RESULTS

Various mutations in the MHR were observed in 14/15 samples: Gly145Arg mutation in 8/13 Adr subtype and 1/2 Ayw subtype samples (60%). The next most common mutation was Gly165Trp in 8/13 Adr subtype but neither of 2 Ayw subtype samples (53.3%). Concurrent antiviral resistance was noted in 5 patients: lamivudine (n = 5), or entecavir (n = 3), but not adefovir, suggesting the occurrence of simultaneous, antiviral cross-resistances. Two patients underwent retransplantation due to the progression of HBV infection despite vigorous antiviral therapy. At diagnosis of HBV recurrence, the mean HBV DNA load was 6.5 × 10(6) copies/mL; 4 patients showed paradoxical coexistence of anti-HBs and HBsAg. Currently, 2 subjects show low-level HBV DNA replication in peripheral blood, although the other 12 had no DNA replication after prolonged antiviral therapy.

CONCLUSIONS

This study suggested that various mutations in the "a" determinant were associated with HBIG resistance. Since treatment failure to rescue antiviral therapy was often associated with delayed detection of HBV recurrence rather than concurrent antiviral resistance, frequent HBV surveillance using more sensitive screening tests, such as HBeAg and HBV DNA polymerase chain reaction assay, seems to be mandatory.

A multi-center, randomized, clinical study to compare the effect and safety of autologous cultured osteoblast(Ossron) injection to treat fractures

BACKGROUND

We performed a multicenter, open, randomized, clinical study of autologous cultured osteoblast injection for long-bone fracture, to evaluate the fracture healing acceleration effect and the safety of autologous cultured osteoblasts.

METHODS

Sixty-four patients with long-bone fractures were randomly divided into two groups, i.e. those who received autologous cultured osteoblast injection and those who received no treatment. The sum of the difference in the callus formation scores after four and eight weeks, was used as the first efficacy variable.

RESULTS

The autologous cultured osteoblast injection group showed fracture healing acceleration of statistical significance, and there were no specific patient complications when using this treatment.

CONCLUSION

Autologous cultured osteoblast injection should therefore be considered as a successful treatment option for treating long-bone fracture.

Lafutidine versus lansoprazole in combination with clarithromycin and amoxicillin for one versus two weeks for Helicobacter pylori eradication in Korea

BACKGROUND AND AIMS

Lafutidine is a novel H(2)-receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7- or 14-day lafutidine-clarithromycin-amoxicillin therapy versus a lansoprazole-based regimen for Helicobacter pylori eradication.

METHODS

Four hundred and sixty-three patients with H. pylori-infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared.

RESULTS

The eradication rates by the intention-to-treat and per-protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention-to-treat and per-protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups.

CONCLUSION

The results of this study showed that lafutidine-clarithromycin-amoxicillin therapy was a safe and effective as lansoprazole-based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option.

Open lateral collateral ligament injury of the interphalangeal joint of the great toe in adolescents during Taekwondo

BACKGROUND

Sports-related open lateral collateral ligament injury of the interphalangeal joint of the great toe has not been previously described in the English literature.

HYPOTHESIS

This injury can occur in adolescents while performing barefooted high-kicking or fast-running exercises involving rapid, 180 degrees turns on a dry, rough, wooden floor in a Taekwondo gymnasium. Injury occurs when the whole body turns quickly while supported only by the plantar aspect of the distal phalanx of the great toe.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The 7 study subjects consisted of 6 boys and 1 girl between 10 and 16 years old. Causes, pattern, mechanism of injury, treatment, and outcomes were investigated.

RESULTS

All patients showed the same injury pattern and mechanism. They all had an open wound on the dorsolateral aspect of the interphalangeal joint. It was postulated that rapid whole body turning supported only by the distal phalanx of the great toe produces nonphysiologic varus stress at the interphalangeal joint, which results in open detachment of the lateral collateral ligament and adjoining periosteum from the proximal phalanx and interphalangeal joint subluxation. All 7 patients regained full great toe function after surgical repair.

CONCLUSION

This unique sports-related open interphalangeal joint injury should be recognized. Participants, trainers, and health providers engaged in Taekwondo or similar sports should understand the pathomechanism of this injury and develop preventive measures.

Do adipose tissue-derived mesenchymal stem cells have the same osteogenic and chondrogenic potential as bone marrow-derived cells?

OBJECTIVE

Adipose tissue-derived mesenchymal stem cells (ATMSCs) have been shown to differentiate into bone, cartilage, fat or muscle. However, it is not certain that ATMSCs are equal to bone marrow-derived mesenchymal stem cells (BMMSC) for their bone and cartilage forming potential. The purpose of this study was to answer the question.

METHODS

BMMSCs were obtained from the medullary canal of femur and ATMSCs were isolated from the fat harvested during liposuction procedures. After cell expansion in culture media and two passages, the immunofluorescent studies for STRO-1 and CD34 were performed to characterize the BMMSCs and ATMSCs. Osteogenesis was induced on a monolayer culture with osteogenic medium containing dexamethasone, beta-glycerophosphate and ascorbate. After 2-3 weeks, alkaline phosphatase (AP) and Von Kossa staining were done. To test for chondrogenesis, mesenchymal stem cells (MSCs) were cultured in a pellet culture and in a fibrin scaffold with a chondrogenic medium (CM) containing transforming growth factor-beta(2) and insulin-like growth factor-I. After 4 weeks, Safranin-O staining and immunohistochemical staining for type II collagen were done to evaluate the chondrogenic differentiation and the matrix production. A histological scale was used to semiquantitatively assess the degree of chondrogenesis.

RESULTS

Both BMMSCs and ATMSCs were STRO-1 positive and CD34 negative. On the test of osteogenesis, the osteoblastic differentiation of ATMSCs as demonstrated by AP staining was much less than that of the BMMSCs (P=0.002). The amount of matrix mineralization shown by Von Kossa staining also showed statistical differences between the two MSCs (P=0.011). On the test for chondrogenesis by the pellet culture ATMSCs showed much weaker presentation as chondrogenic cells in both cell morphology and the matrix production. The histological score was 6.5 (SD1.3) for the BMMSCs, and 4.3 (SD1.6) for the ATMSCs cultured in CM, which was statistically significant (P=0.023). The results from fibrin gel paralleled those from the pellet culture in general.

CONCLUSION

The results of our study suggest that the ATMSCs may have an inferior potential for both osteogenesis and chondrogenesis compared with the BMMSCs, and these cast doubts on the value of adipose tissue as a source of MSCs.

Littoral cell angioma (LCA) associated with liver cirrhosis

A littoral cell angioma (LCA) is a rare benign vascular tumor of the spleen. A 60-year-old man, with multiple nodules in imaging study and liver cirrhosis graded as Child-Pugh classification class A, was transferred for splenomegaly. A thrombocytopenia was found on hematological evaluation. Because there was no evidence of hematological and visceral malignancy, a splenectomy was performed for a definitive diagnosis. The histological and immunohistochemical features of the splenic specimens were consistent with a LCA. After the splenectomy, the thrombocytopenia recovered to the normal platelet count. There has been no previous report of a LCA combined with liver cirrhosis. Herein, the first case of a LCA in Korea, diagnosed and treated by a splenectomy, is reported.

Fractures to the Posterior Wall of the Acetabulum Managed With Screws Alone

BACKGROUND

The use of a buttress plate in addition to lag screws has been recommended for fractures to the posterior wall of the acetabulum. However, there is a lack of possible criteria for the use of screws alone. This study aimed to evaluate the use of screws alone for fixation of posterior wall fractures to the acetabulum.

METHODS

This study retrospectively examined 15 patients with a single fragmented or moderately comminuted posterior wall fracture of the acetabulum who had been treated with internal fixation using screws alone. The modified D'Aubigne and Postel's score system was used for the functional evaluation.

RESULTS

The clinical results were excellent for nine hips, very good for one hip, good for four hips, and poor for one hip after follow-up period of more than 2 years.

CONCLUSION

The use of screws alone can produce acceptable results for selected posterior wall fractures of the acetabulum.

Potentially unstable intertrochanteric fractures

OBJECTIVES

Evaluation of risk factors for loss of reduction in initially stable intertrochanteric fractures.

DESIGN

Retrospective database analysis.

SETTING

University teaching hospital.

PATIENTS/PARTICIPANTS

Sixty-six patients over the age of 55 years presenting with fractures of the trochanteric region caused by a low-energy injury, classified as AO/OTA type 31-A1 (stable fracture in Evans classification).

INTERVENTION

Treatment with a sliding compression hip screw.

MAIN OUTCOME MEASUREMENT

The outcome examined in this study was loss of reduction as measured by the amount of medialization of the femoral shaft.

RESULTS

Increased age (P = 0.01) and comminution of the lateral cortex (P = 0.0001) were factors significantly associated with excessive displacement. These 2 factors had a high degree of correlation (r = 0.76).

CONCLUSIONS

A surgeon must be aware of iatrogenic fragmentation of the lateral cortex at the time of surgery in apparently stable intertrochanteric fractures in older patients because of the potential for subsequent loss of reduction.

Significance of non-erosive minimal esophageal lesions in gastro-esophageal reflux disorder

BACKGROUND

Non-erosive reflux disorder, which represents more than 60% of gastro-esophageal reflux disorders, lacks objective parameters for diagnosis. The purpose of this study was to evaluate the correlation between non-erosive minimal lesions at the lower esophagus and gastro-esophageal reflux disorder.

METHODS

Patients were asked to answer a symptom questionnaire. The endoscopic findings were either graded by LA classification or recorded as non-erosive minimal lesions. Patients with minimal lesions were treated with rabeprazole or a placebo and responses were evaluated at weeks 1 and 4.

RESULTS

In 8 centers, 3454 patients were screened. In patients with heartburn or acid regurgitation as the most bothersome symptom, 23.7% had endoscopy negative reflux disorder, 40.1% showed minimal lesions, and 36.20% had mucosal break esophagitis. Thirty-four percent of patients with minimal lesions and 39.1% of patients with LA 'grade A' mild esophagitis reported typical reflux symptoms as their main symptom. In patients with minimal lesions, medication with rabeprazole reduced symptoms significantly at weeks 1 and 4, but not with the placebo.

CONCLUSION

Patients with non-erosive minimal esophageal lesions had similar reflux symptoms comparable to those with mild erosive reflux esophagitis, and reflux symptoms were improved with a short-term proton pump inhibitor. Thus, non-erosive minimal esophageal lesion constitutes a great part of gastro-esophageal reflux disorder.

Survival and prognostic factors in patients with primary pulmonary hypertension

OBJECTIVES

Primary pulmonary hypertension (PPH) that affects predominantly young and productive people is a progressive fatal disease of unknown cause. The objectives of this study were to characterize mortality in patients with PPH and to investigate the factors associated with their survival.

METHODS

Thirteen patients with PPH were enrolled between 1988 and 1996 and followed-up through July 1999. Measurements at diagnosis included hemodynamic and pulmonary function variables in addition to information on demographic data and medical history.

RESULTS

1) The mean age of the patients with PPH enrolled into the study was 36.1 +/- 9.3 years with female predominance. 2) The estimated median survival was 3.4 +/- 0.6 years. 3) Decreased cardiac index was the only significant predictor of mortality (Cox proportional hazards model).

CONCLUSION

Patients with PPH have a poor survival expectancy. In this limited study with a small number of patients, mortality is largely associated with decreased cardiac index.

Two cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice

We recently treated two cases of chronic pancreatitis with obstructive jaundice due to compression of the common bile duct by pancreatic pseudocyst. The two cases were males admitted with the complaint of icteric skin color. The first, a 46-year-old male, admitted with the complaint of icteric skin color. He was treated by operative cystojejunostomy after percutaneous drainage of the pseudocyst and percutaneous transhepatic biliary drainage. The other case was a 58 year-old male who admitted with the complaint of icteric skin color. He had an infected pseudocyst in the pancreas and was endoscopically treated. Both of them were discharged with favorable clinical course and normal laboratory findings after the treatment. The former patient remained well 11 months after treatment, but the latter patient died from necrotizing pancreatitis and septic shock 6 months after treatment. Most cases of obstructive jaundice associated with pseudocysts appear to be due to fibrotic stricture of the intrapancreatic portion of the common bile duct rather than due to compression of the bile duct by the pseudocyst. In a patient with secondary pancreatic infection or obstructive jaundice following pancreatic disease, differentiating between these two conditions is an important aspect of accurate diagnosis and therapy. Herein we report two unusual cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice.

Role of adenosine A(2B) receptors in vasodilation of rat pial artery and cerebral blood flow autoregulation

This study was aimed to investigate the underlying mechanism of vasodilation induced by the activation of A(2B) adenosine receptors in relation to cerebral blood flow (CBF) autoregulation. Changes in pial arterial diameters were observed directly through a closed cranial window. N(omega)-nitro-L-arginine methyl ester (L-NAME, nitric oxide synthase inhibitor) significantly suppressed the concentration-dependent vasodilations induced by adenosine and 5'-N-ethylcarboxamido-adenosine (NECA) but not the vasodilation by CGS-21680 (A(2A)-receptor agonist). Moreover, NECA-induced vasodilation was suppressed by alloxazine (1 micromol/l) but not by ZM-241385 (1 micromol/l, A(2A) antagonist), which suggests mediation by A(2B)- receptor activation. Otherwise, the level of nitrite/nitrate was concentration dependently increased in the artificial cerebrospinal fluid (CSF) when adenosine and NECA were suffused over the cortical surface. L-NAME and alloxazine, but not ZM-241385, largely inhibited their releases. The lower limit of CBF autoregulation was little affected following pretreatment with L-NAME or alloxazine. Thus it is suggested that adenosine-induced vasodilation via activation of A(2B)-adenosine receptors of the rat pial artery is coupled to the production of nitric oxide, which contributes little to CBF autoregulation.

Hypocholesterolemic effect of naringin associated with hepatic cholesterol regulating enzyme changes in rats

The effects of the citrus bioflavonoid naringin were tested by using it as a supplement in a high-cholesterol diet. Male rats were fed for 42 days with a 1% (wt/wt) high cholesterol diet either with or without naringin-supplementation (0.1%, wt/wt) to study the effect on plasma lipid levels, hepatic lipid contents, hepatic enzyme activity, and the excretion of fecal neutral sterols. Naringin did not significantly alter the levels of plasma triglycerides, however, the levels of plasma cholesterol (3.80 +/- 0.31 mmol/L vs. 2.61 +/- 0.30 mmol/L, mean +/- SE; p < 0.05) and hepatic cholesterol (70.3 +/- 4.3 mg/g vs. 54.3 +/- 3.8 mg/g, mean +/- SD; p < 0.05) were significantly lowered compared to those of the control. HMG-CoA reductase (2487.0 +/- 210.0 pmole/min/mg vs. 1879.0 +/- 236.0 pmole/min/mg, mean +/- SE; p < 0.05) and ACAT (806.0 +/- 105.0 pmole/min/mg vs. 643.0 +/- 80.0 pmole/min/mg, mean +/- SE; p < 0.05) activities were both substantially lower in the naringin-supplemented group than in the control. The naringin supplementation markedly decreased the excretion of fecal neutral sterols (204.7 +/- 28.5 mg/day) compared to the control (521.9 +/- 53.9 mg/day). The combination of the inhibited HMG-CoA reductase (-24.4%) and ACAT (-20.2%) activities as a result of naringin supplementation could account for the decrease of fecal neutral sterols.

Pharmacological profiles of SKP-450 and its family, a K+ channel opener, in comparison with levcromakalim

This study was carried out to characterise the vasodepressor and vasorelaxant actions of a benzopyran derivative, SKP-450 and its family, (+/-)-racemate SKP-411, (+)-enantiomer SKP-451, and the metabolites of SKP-450 (SKP-818 and SKP-310) in comparison with levcromakalim (LCRK) in the canine coronary, rabbit basilar and vertebral arterial segments. SKP-450, its family (SKP-411 and SKP-451) and the metabolite of SKP-450 (SKP-818) caused concentration-dependent relaxations as well as LCRK in the canine coronary artery and rabbit basilar and vertebral arteries. The relaxant potency of SKP-450 was significantly higher than that of LCRK in the three arteries in terms of EC50 values. SKP-450- and LCRK-induced vasorelaxations were competitively antagonised by glibenclamide with pA2 values of 7.60 (slope 1.22) and 7.99 (slope, 1.00), respectively. SKP-450 (0.1 and 1.0 microM) caused a significant stimulation of the 86Rb efflux from canine coronary arteries in a concentration-dependent manner as well as LCRK (1 and 10 microM), and their effects were antagonised by glibenclamide (10 microM). SKP-450 as well as LCRK produced long-lasting decreases in mean arterial pressure in the spontaneously hypertensive rats (SHR). These results suggest that SKP-450 has a significantly higher potency than LCRK in in vitro vasorelaxation, and it exerts potent and long-lasting vasodepressor effects with its active metabolite (SKP-818).

Decreased CGRP level with increased sensitivity to CGRP in the pial arteries of spontaneously hypertensive rats

It was aimed to investigate the importance of calcitonin gene-related peptide (CGRP) in maintenance of normal cerebral microcirculation. We examined both the functional (in vivo) and biochemical effects (in vitro) of CGRP on the pial arteries of spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY). When mock cerebrospinal fluid containing capsaicin (3 x 10(-7) M) was suffused over the cortical surface, the diameter of pial arteries of SHR was transiently increased and rapidly returned to the baseline level, while the capsaicin-induced increase in pial arterial diameters of WKY was large and sustained for a longer duration (> 10 min). Capsaicin-induced vasodilation was significantly attenuated by pretreatment with CGRP8-37, a CGRP1, receptor antagonist, in both WKY and SHR. On the other hand, cortical suffusion with CGRP (10(-9) approximately 10(-6) M) exerted a larger enhancement in the vasodilation of pial artery of SHR than WKY. The CGRP-induced vasodilation was significantly antagonized by CGRP8-37 in both WKY and SHR. The released level of CGRP-like immunoreactivity (CGRP-LI) from the pial artery was significantly lower in SHR (12.3 +/- 1.2 fmol/mm2/hr) than that in WKY (24.5 +/- 3.9 fmol/mm2/hr). CGRP (10(-6) M)-induced stimulation of cyclic AMP formation was rather larger in the pial arteries from SHR (50.2 +/- 5.8 fmol/mm2/30 min, p < 0.05) than those from WKY (34.5 +/- 3.8 fmol/mm2/30 min). These data suggest that, in the pial arteries of SHR, the transient vasodilation to capsaicin and enhanced vasodilation to CGRP are related to the decreased CGRP level in the cerebral microvascular beds, consequently leading to increased sensitivity of the CGRP receptors to CGRP.

Characterization of PD 121981- and CGP 42112-induced unmasking of low concentration effects of angiotensin II in rabbit abdominal aorta

The unmasking of the low concentration effect of angiotensin II (AII) was identified within the concentration ranges of 10(-13) to 10(-11) M of AII by PD 121981 (5-diphenylacetyl-1-(4-methoxy-3-methylbenzyl)- 4,5,6,7-tetrahydro-1H-imidazo[4,5-c]-pyridine-6-carboxylic acid) and 10(-12) to 3 x 10(-10) M of AII by CGP 42112 (nicotinic acid-Tyr-(N alpha-benzyl-oxycarbonyl-Arg)Lys-His-Pro-IIe-OH), AT2 antagonists, in association with the ordinary contraction curve, i.e., high concentration effect (at 3 x 10(-10)-10(-6) M of AII), in the rabbit abdominal aorta. Thus, they showed clear biphasic features of AII-induced contraction curves. However, this was not the case for angiotensin I and angiotensin III. This PD 121981-evoked low concentration effect of AII was selectively inhibited by DuP 753 (0.01-1 nM), dithiothreitol (10 and 100 microM), pertussis toxin (50 and 300 ng/ml, for 2 hr), nifedipine (1 and 10 microM) and 8-(diethylamino)octyl 3,4,5-trimethoxybenzoate hydrochloride (1 and 3 microM), which suggests the receptors were the AT1 subtype. However, the high concentration effect of AII was not affected by these drugs within the concentration ranges used in the present studies. These myographic results were almost consistent with the features of the intracellular Ca++ changes. Thus, it was concluded that the receptors that mediate the low concentration effect of AII belong to the AT1 subtype. However, the current study did not determine the mechanism by which PD 121981 and CGP 42112 evoked the up-regulation of the AT1 receptors.

Effect of ouabain on relaxation induced by cromakalim in human and canine mesenteric arteries

We investigated the effect of cromakalim, a K+ channel opener, that activates indirectly the Na(+)-K+ pump, in association with increased K+ conductance in the mesenteric arteries. In 65% of human mesenteric arteries tested, the concentration-dependent relaxation curves for cromakalim were biphasic: the low concentration (< 10(-7) M) effect was preferentially inhibited by ouabain, whereas the higher concentration effect was significantly inhibited by glibenclamide. In branches of canine mesenteric artery, the cromakalim-induced relaxation was inhibited by pretreatment with ouabain (1 microM) as well as by glibenclamide (1 microM). The reduction in contraction of human and canine mesenteric arterial strips caused by cromakalim was totally reversed by pretreatment with ouabain (1 microM) or glibenclamide (1 microM). On the other hand, in canine mesenteric artery, cromakalim caused a significant stimulation of 22Na+ influx and ouabain-sensitive 86Rb+ uptake in association with increased 86Rb+ efflux, all of which were inhibited by glibenclamide (1 microM). Thus, it is suggested that cromakalim possesses the additional property to stimulate the Na(+)-K+ pump through an elevation in intracellular Na+, resulting in strong relaxation of blood vessels.

Release of superoxide-dependent relaxing factor(s) from endothelial cells

In the present work, an experimental system was designed to study superoxide anion radical, implicated as the cause of vascular dilatation. To circumvent its direct effect, we employed a two-bath system. When the endothelial cells (EC) were exposed to electrical field stimulation (EFS) or to a hypoxanthine-xanthine oxidase system in bath A plus its physiological buffer solution suffused on a helical strip of cat basilar artery in bath B, the contraction to 5-hydroxytryptamine (5-HT) was depressed to approximately 40-50% of the control value. The reduction was not elicited on EFS in a state of calcium deficiency or in the absence of EC. The depression could be prevented by pretreatment with superoxide dismutase (SOD), but not with an effective dose of catalase, dimethyl sulfoxide (DMSO), mannitol, or indomethacin. The percent depression of contraction was paralleled by an increase in SOD-inhibitable cytochrome c reduction, which was not associated with cyclic guanosine 3',5'-monophosphate formation. These results suggest that superoxide-dependent relaxing factor is released from EC differently than the endothelium-derived relaxing factor mediated by acetylcholine.

Assessment of superoxide-mediated release of vascular-inhibitory factor(s) from endothelial cells by using a two-bath system

Release of a vascular-inhibitory factor from endothelial cells (EC), different from endothelium-derived relaxant factor (EDRF), was identified through use of a two-bath system. This two-bath system precluded the effects of oxygen-free radicals that appear when electrical field stimulation (EFS) is directly imposed on detector muscle.

Observation of the serum uric acid in essential hypertension

In order to observe the relationship of hyperuricemia and essential hypertension, we studied serum uric acid in 139 patients with essential hypertension visiting the Department of Internal Medicine, Pusan National University Hospital, between May 1982 and July 1983, and analyzed its values in terms of various clinical and laboratory parameters.

The mean concentration of serum uric acid and incidence of hyperuricemia in essential hypertension were 6.60 ± 1.96 mg%, 57.9% and those of the normal control group were 3.87 ± 1.30 mg%, 17.8%, respectively with significantly higher values in the hypertension group. The mean concentration of serum uric acid and the incidence of hyperuricemia were significantly correlated with the levels of diastolic blood pressure, mean arterial pressure, BUN, and serum creatinine. Significant correlation between the mean concentration of serum uric acid and the extent of target organ damage and abnormal urine findings were observed.

Technetium-99m pyrophosphate scintigraphy for the detection of acute myocardial infarction. How useful is it?

To evaluate the contribution of Tc-99m pyrophosphate scintigraphy (TPS) on the overall management of patients suspected of having acute myocardial infarction (AMI), hospital records of 58 consecutive patients who underwent TPS, were evaluated in depth. The results indicate that TPS was essential for the diagnosis of AMI in 16% of the patients. TPS was most rewarding in perioperative patients and in patients with borderline or uninterpretable electrocardiographic and enzyme changes. Also, in some cases, TPS was able to confirm or exclude the diagnosis of AMI prior to the confirmation by serial electrocardiograms (ECG) and serial enzyme changes. TPS was less rewarding in patients with clinically low index of suspicion for AMI. It may also be confusing in patients with high clinical likelihood of AMI and a history of prior myocardial infarction because of the possibility of persistently positive TPS in some of these patients. Considering the limitations of ECGs, the cardiac enzymes, and atypical clinical presentations in the patient population we evaluated, TPS appears to be fairly accurate when the scintigraphic findings are compared with the final diagnosis at the time of discharge from the hospital.