Endogenous gastrin stimulates regeneration of remnant pancreas after partial pancreatectomy

The purpose of this study was to evaluate the effect of endogenous gastrin on pancreatic regeneration after a partial pancreatectomy in the rat. Sixty rats were divided into 6 groups. Groups I and II received sham operation (splenectomy only), and groups III, IV, V, and VI received both 66% partial pancreatectomy (PPx) and splenectomy. Endogenous hypergastrinemia was induced in groups II, IV, and VI by gavage of Lansoprozole (LSP) for three weeks. In groups V and VI, gastrin receptor blocker, L365,260, was given continuously using an osmotic minipump. Following three weeks of treatment, PPx alone increased the pancreatic weight and protein content, but not RNA or DNA content (Group III). In the PPx groups, the pancreatic weight, and contents of protein, RNA, and DNA were significantly increased in the LSP treated rats (Group IV). This effect was abolished by L365,260 (Group VI). This results suggest that endogenous gastrin specifically stimulates regeneration of the remnant pancreas after partial pancreatectomy in rat. Induction of endogenous hypergastrinemia may be useful in patients following pancreatic resection for the prevention and treatment of pancreatic insufficiency.

Industrial scale production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Large scale production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] by Aeromonas hydrophila 4AK4 was examined in a 20,000 l fermentor. Cells were first grown using glucose as a carbon source, and polyhydroxyalkanoate (PHA) biosynthesis was triggered by the addition of lauric acid under conditions of limited nitrogen or phosphorus. When cells first grown in a medium containing 50 g glucose l(-1) were further cultivated after the addition of 50 g lauric acid l(-1) under phosphorus limitation, a final cell concentration, PHA concentration and PHA content of 50 g l(-1), 25 g l(-1), and 50 wt%, respectively, were obtained in 46 h, equivalent to PHA productivity of 0.54 g l(-1)t h(-1). The copolymer produced was found to be a random copolymer, and the 3HHx fraction was 11 mol%.

Clinical characteristics of constrictive pericarditis diagnosed by echo-Doppler technique in Korea

A retrospective analysis of clinical data of 71 patients with constrictive pericarditis (CP) diagnosed by echo-Doppler technique (mean age, 49+/-17) was done. In 27 patients (38%), the etiology was unknown, and the three most frequent identifiable causes were tuberculosis (23/71, 32%), cardiac surgery (8/71, 11%), and mediastinal irradiation (6/71, 9%). Pericardiectomy was performed in 35 patients (49%) with a surgical mortality of 6% (2/35), and 11 patients (15%, 11/ 71) showed complete resolution of constrictive physiology with medical treatment. Patients with transient CP were characterized by absence of pericardial calcification, shorter symptom duration, and higher incidence of fever, weight loss, and tuberculosis. The 5-yr survival rates of patients with transient CP and those undergoing pericardiectomy were 100% and 85+/-6%, respectively, which were significantly higher than that of patients without undergoing pericardiectomy (33+/-17%, p=0.0083). Mediastinal irradiation, higher functional class, low voltage in ECG, low serum albumin, and old age were the independent variables associated with a higher mortality. Tuberculosis is still the most important etiology of CP in Korea, and not infrequently, it may cause transient CP. Early diagnosis and decision-making using follow-up echocardiography are crucial to improve the prognosis of patients with CP.

Stimulation of fracture healing in a canine ulna full-defect model by low-intensity pulsed ultrasound

Because no report has been issued on the healing effects of low-intensity pulsed ultrasound on moderate to large fracture gaps, we performed an experimental study using a canine ulna full-defect model. Ten mongrel male dogs were divided into two groups: a small defect group and large defect group. The defects were made on the middle one third of both ulnae and one side only was randomly selected for ultrasound sonication, at 1 MHz, 200 microsecond bursting sine wave in 50 mW/cm2 spacial average and temporal average. Sonication was started on the day after surgery and applied for 15 minutes once a day for six days a week. In the small defect group, the means of the radiologic scores, as described by Lane and Sandhu, were 0.6, 4.4, and 8.4 in the control side and 1.8, 6.0, and 10.4 in the treatment side one, three, and five months after the operation, respectively (p=0.0372). In the large defect model, the corresponding means were 2.2, 3.4, and 6.0 in the control side and 3.3, 5.4, and 9.2 in the treatment side (p= 0.009). Low-intensity pulsed ultrasound enhanced new bone formation in small and large full-defects and decreased the incidence of nonunion in the large defect model.

Characteristics of Korean native, Hanwoo, calves produced by transfer of in vitro produced embryos

The main objectives of this investigation were to monitor the birth weight of calves and gestation length following artificial insemination (AI) and transfer of in vivo or in vitro produced Korean native, Hanwoo embryos. Embryos produced in vivo were recovered from uterine flushings of superovulated cows 7 days after AI. Those embryos produced in vitro were co-cultured with cumulus cells for 7-8 days after in vitro fertilization. The birth weights of calves following the transfer of in vitro produced (IVP) embryos were heavier than calves from both of AI- and in vivo-derived embryo transferred calves in both sexes (29.6, 24.1 and 25.2kg, respectively, P<0.05). The IVP calves also had a longer gestation length (293.9, 285.8 and 283.8 days, respectively, P<0.05).

Regulation of apoptosis by somatostatin and substance P in peritoneal macrophages

Recent studies have shown that somatostatin (SOM) inhibits interleukin 6 (IL-6) and interferon gamma (IFNgamma) production by lymphocytes and peritoneal macrophages, whereas substance P (SP) enhances these cytokines production. To define the mechanism of the cytokine production enhancements and inhibitions by SOM and SP, we examined the expression of apoptosis modulator, p53, Bcl-2, Bax, inducible nitric oxide synthase (iNOS), Fas, caspase-8 and nitric oxide (NO) in thioglycolate-elicited peritoneal macrophages. SOM caused up-regulation of p53, Bcl-2, Fas and caspase-8 activities, and down-regulation of iNOS expression and NO production. On the other hand, SP slightly induces p53 and highly induces Bcl-2, iNOS expression and NO production. These data suggest that apoptosis by SOM may occur by a Bax- and NO-independent p53 accumulation, and through Fas and caspase-8 activation pathways, and that the inducible expression of Bcl-2 and NO production by SP may contribute to prevent the signals of apoptosis by Bax, and via Fas and caspase-8 activation.

Self-assembled nanoscale capsules between resorcin[4]arene derivatives and Pd(II) Pt(II) complexes

Nanoscale molecular capsules have been prepared by self-assembly of resorcin[4]-arene derivatives and Pd(II) or Pt(II) complexes; the positively charged N-alkylpyridinium derivatives are encapsulated inside capsules due to strong cation-pi interactions.

Treatment of diffuse in-stent restenosis with rotational atherectomy followed by radiation therapy with a rhenium-188-mercaptoacetyltriglycine-filled balloon

OBJECTIVES

This study was done to evaluate the feasibility and efficacy of beta-radiation therapy with a rhenium-188-mercaptoacetyltriglycine ((188)Re-MAG(3))-filled balloon after rotational atherectomy for diffuse in-stent restenosis (ISR).

BACKGROUND

Rotational atherectomy has been shown to be safe and efficient for the treatment of ISR, but the recurrence rate is still high. Intracoronary beta-irradiation after rotational atherectomy may be a reasonable approach to prevent recurrent ISR.

METHODS

Fifty consecutive patients with diffuse ISR (length >10 mm) in native coronary arteries underwent rotational atherectomy and adjunctive balloon angioplasty, followed by beta-irradiation using a (188)Re-MAG(3)-filled balloon catheter. The radiation dose was 15 Gy at a depth of 1.0 mm into the vessel wall.

RESULTS

The mean lengths of the lesion and irradiated segment were 25.6 +/- 12.7 mm and 37.6 +/- 11.2 mm, respectively. Radiation was delivered successfully to all patients, with a mean irradiation time of 201.8 +/- 61.7 s. No adverse event, including myocardial infarction, death or stent thrombosis, occurred during the follow-up period (mean 10.3 +/- 3.7 months), and nontarget vessel revascularization was needed in one patient. The six-month binary angiographic restenosis rate was 10.4%, and the loss index was 0.17 +/- 0.31.

CONCLUSIONS

Beta-irradiation using a (188)Re-MAG(3)-filled balloon after rotational atherectomy is safe and feasible in patients with diffuse ISR, and it may improve their clinical and angiographic outcomes. Further prospective, randomized trials are warranted to evaluate the synergistic effect of debulking and irradiation in patients with diffuse ISR.

The clinical and ocular manifestations of Takayasu arteritis

PURPOSE

To evaluate the clinical and ocular manifestations of Takayasu arteritis and the fundus fluorescein angiography (FFA) characteristics of Takayasu retinopathy (TR).

PATIENTS AND METHODS

Medical records and fundus fluorescein angiograms of 156 eyes of 78 patients with Takayasu arteritis were reviewed. Fundus FA using a wide-field fundus camera (60 degrees) was performed in 19 patients, and conventional angiography or spiral computed tomographic angiography was performed in all 78 patients.

RESULTS

The series included 67 female and 11 male patients; mean age at time of diagnosis was 26.7 years (range, 4-61 years). Hypertension was found in 44 (56.4%) patients, ischemic cerebrovascular symptoms in 18 (23.1%) patients, and amaurosis fugax in 20 (25.6%) patients. On fundus examination, no retinopathy was found in 87 (55.8%) eyes; hypertensive retinopathy was found in 48 (30.8%) eyes; and TR was found in 21 (13.5%) eyes. Patients with TR had carotid artery or aortic arch involvement, and patients with hypertensive retinopathy had involvement of the descending aorta or renal artery and sparing of the carotids. Best-corrected visual acuity in TR Stage 1 to 3 ranged from 20/15 to 20/30, but in Stage 4, it ranged from 20/200 to hand motions because of secondary ocular complications. On FFA, the arm-to-retina circulation time was prolonged in all 21 eyes with TR (mean, 22.7+/-8.9 seconds), but only 14 eyes showed delayed arteriovenous filling time, which was mainly found in chronic, moderate to severe TR, Stage 3 or 4. Arteriovenous anastomosis was found in all 12 eyes with Stage 3 and 4 TR.

CONCLUSIONS

Delayed arm-to-retina circulation time is shown in all cases of TR, but delayed arteriovenous filling time is mostly found in moderate and severe TR. During ophthalmic examination, the delay of arteriovenous filling time and formation of arteriovenous anastomosis must be examined carefully to prevent visual deterioration.

Dissolution of poorly crystalline apatite crystals by osteoclasts determined on artificial thin-film apatite

Poorly crystalline apatite (PCA) crystals introduced into bone tissue should be stable for a definite period before they are dissolved as a result of a host response. In this report, the dissolution of PCA crystals by the action of osteoclasts was studied on artificial thin films. These consisted of PCA crystals having similar crystallographic properties to bone crystals which were developed for assaying the osteoclast activity in vitro. The dissolution of minerals by osteoclasts decreased along with the decreased amount of labile phosphate and hydrogen phosphate domains of apatite crystals, which were caused by the crystal maturation temperature. A profound effect on mineral dissolution by pH in the culture medium was also shown. Low acidity considerably increased mineral dissolution, whereas a slight alkalinity totally blocked mineral dissolution. There was little difference in the mineral dissolution behavior of osteoclasts near the physiologic pH. In addition, it was determined whether mineral dissolution by osteoclasts was dependent on the destruction of the organic matrix. Nocodazole was introduced to inhibit the secretion of hydrolytic enzymes, and acetazolamide was added to inhibit acid production by the osteoclasts. There was no significant change as a result of nocodazole addition on mineral dissolution or by the addition of acetazolamide on degradation of collagen. These results indicate that small changes in the physicochemical properties of apatite crystals can decrease resorption by osteoclasts, which can be highly activated at low pH. These results also suggest that mineral dissolution and organic degradation by osteoclasts are self-regulating.

Determinants and prognostic implications of terminal QRS complex distortion in patients treated with primary angioplasty for acute myocardial infarction

Terminal QRS complex distortion on admission has an impact on a patient's prognosis after primary angioplasty for acute myocardial infarction (AMI). We evaluated the determinants and prognostic significance of terminal QRS complex distortion in 153 consecutive patients with AMI after primary angioplasty. The study population was divided into 2 groups according to the presence (group I, n = 41) or absence (group II, n = 112) of terminal QRS complex distortion. The primary end points were the occurrence, within 6 weeks after AMI, of death, nonfatal reinfarction, or congestive heart failure. Baseline characteristics were similar between the 2 groups. However, patients in group I had higher peak levels of serum creatine kinase than those in group II (5,100 +/- 3,100 vs 3,000 +/- 1,800 U/L, respectively, p <0.01). The rate of angiographic no-reflow (Thrombolysis In Myocardial Infarction flow grade < or =2) was 31.7% in group I and 10.7% in group II (p <0.01). The predischarge left ventricular ejection fraction was 45.0 +/- 12.0% in group I and 54.0 +/- 8.0% in group II (p <0.01). Multivariate analysis identified the pressure-derived fractional collateral flow index and the culprit lesion in the left anterior descending coronary artery as independent determinants of the terminal QRS complex distortion. No patients died during 6 weeks of follow-up. The 2 groups were similar for life-threatening arrhythmia or reinfarction. However, there were more patients in group I than in group II with congestive heart failure (26.8% vs 5.4%, respectively, p <0.01) or who reached the primary end points (29.3% vs 5.4%, respectively, p <0.01). In conclusion, terminal QRS complex distortion on admission is associated with poor clinical outcome after primary angioplasty for AMI, and collateral flow may have a major influence on terminal QRS complex distortion during AMI.

Diagnosis of nut-cracker phenomenon using renal Doppler ultrasound in orthostatic proteinuria

BACKGROUND

We evaluated the efficacy of non-invasive renal Doppler ultrasound (US) to detect the nut-cracker phenomenon (NCP) and we studied the prevalence of NCP in children with orthostatic proteinuria.

METHODS

Among a total 66 cases of orthostatic proteinuria, 39 cases of NCP were found, with 27 cases being detected in a normal control group. Using Doppler US, the anteroposterior (AP) diameter and peak velocity (PV) of the left renal vein (LRV) were measured at the hilar and aortomesenteric portion. We calculated the ratio of AP and PV diameters between the two portions. The parameters were analysed using Student's t-test.

RESULTS

The AP diameters and the ratio in the hilar and narrow portions were all significantly different between the two groups (P<0.01). The PV in the narrow portion and the ratio of PV were significantly different (P<0.01), but the PV in the hilar portion was not statistically different between the two groups (P>0.05). If the diagnostic criteria for NCP was that the ratio of PV was more than 5, then 22 subjects (56.4%) in the orthostatic proteinuria group and none in the control group could be diagnosed as NCP. If, however, the cut-off values for the diagnosis of NCP were set at the mean+/-2 SD of the ratio (PV ratio 3.98 and size ratio 4.16), then the orthostatic proteinuria group showed abnormal AP diameter in 25 (64.1%), peak velocity in 28 (71.8%), and both in 21 patients (53.8%), and the control group showed an abnormal AP diameter in one subject (3.7%).

CONCLUSIONS

NCP may be one of the leading causes of orthostatic proteinuria, and non-invasive renal Doppler US may be a useful diagnostic tool in the screening of NCP. In the future, the diagnostic criteria of NCP must be redefined in children.

A study on the distribution of chlorination by-products (CBPs) in treated water in Korea

Fifteen chlorination by-products were analyzed in 416 water samples collected from 35 water treatment plants in Korea from 1996 to 1998. These samples were divided into five groups according to water sources (Han-river, Nakdong-river, Youngsan-river, Kum-river and Cheju) and detected CBPs were classified into six classes (trihalomethanes; THMs, haloacetic acids; HAAs, haloacetonitriles: HANs haloketones; HKs, chloralhydrate; CH, chloropicrin; CP) and then, it was observed the detection tendency and frequency of CBPs in each water source. The total concentration of CBPs in treated water from Nakdong-river or Han-river was higher than those from the other rivers. And the distribution pattern of each class of CBPs was similar in all water sources. THMs were the highest portion in the range of 40-50%, and HAAs and HANs were 28-35 and 9-15%, respectively. And there was a strong correlation between HANs and HKs (r=0.813). Each and total concentrations of CBPs showed to be more affected by the water source in two-way analysis of variance (two-way ANOVA) among the concentration of CBPs, the source of water and season.

Osteoclastogenesis is enhanced by activated B cells but suppressed by activated CD8(+) T cells

Host immune response is known to contribute to the progression of periodontitis, and alveolar bone destruction in periodontitis is associated with enhanced osteoclast activity. Therefore, we evaluated the roles of activated lymphocyte subsets in osteoclastogenesis. Osteoclast precursors were co-cultured with activated lymphocytes (B, CD4(+) T, CD8(+) T) in the presence of either macrophage colony-stimulating factor (M-CSF) alone or M-CSF plus soluble receptor activator of NF-kappaB ligand (sRANKL), and subsequent differentiation into active osteoclasts was evaluated by a resorption assay. The activated B and CD4(+) cells, but not CD8(+) T cells, induced osteoclast differentiation in the presence of M-CSF alone. In the presence of M-CSF and sRANKL, B cells induced the formation of small but highly active osteoclasts and increased resorption, while CD8(+) T cells profoundly suppressed osteoclastogenesis. Co-culture using an insert well or supernatant suggested that both B and CD8(+) T cells acted on osteoclasts mostly via soluble proteins. Activated B cells expressed many osteoclastogenic factors including RANKL, TNF-alpha, IL-6, MIP-1alpha, and MCP-3. CD8(+) T cells expressed a substantial amount of osteoprotegerin (OPG) along with RANKL. However, blocking antibody to OPG did not reverse the suppression by CD8(+) T cells, suggesting that other factor(s) are involved. Taken together, activated B cells promoted osteoclastogenesis, while CD8(+) T cells inhibited the osteoclast formation via direct interaction. The results imply the importance of lymphocyte subpopulations in the development of periodontitis.

Functional Interaction of bZIP Proteins and the Large Subunit of Replication Factor C in Liver and Adipose Cells

The transcription factor CCAAT/enhancer-binding protein-alpha (C/EBPalpha) has a vital role in cell growth and differentiation. To delineate further a mechanism for C/EBPalpha-mediated differentiation, we screened C/EBPalpha-interacting proteins through far-Western screening. One of the strongest interactions was with RFC140, the large subunit of the replication factor C complex. C/EBPalpha specifically interacted with RFC140 from rat liver nuclear extract as determined by a combination of affinity chromatography and co-immunoprecipitation. Subsequent far-Western blotting showed that the bZIP domain of C/EBPalpha interacted with the DNA-binding region of RFC140. Overexpression of RFC140 in mammalian cells increased the transactivation activity of C/EBPalpha on both minimal and native promoters. Consistent with the enhanced transactivation, a complex of C/EBPalpha and RFC140 proteins with the cognate DNA element was detected in vitro. The specific interaction between C/EBPalpha and RFC140 was detected in the terminal differentiation of 3T3-L1 preadipocytes to adipocytes. The synergistic transcription effect of these two proteins increased the promoter activity and protein expression of peroxisome proliferator-activated receptor-gamma, which is a main regulator of adipocyte differentiation. Our results demonstrate that the specific transcription factor C/EBPalpha and the general DNA replication factor RFC140 interact functionally and physically. This observation highlights a unique mechanism by which the levels of the general replication factor can strongly modulate the functional activity of the specific transcription factor as a coactivator.

Prognostic significance of cerebral metabolic abnormalities in patients with congestive heart failure

BACKGROUND

Cerebral metabolic abnormalities were proposed as a potential marker of disease severity in congestive heart failure (CHF), but their prognostic significance remains uncertain.

METHODS AND RESULTS

We investigated the prognostic value of cerebral metabolic abnormalities in 130 consecutive patients with advanced CHF (100 men aged 42.6+/-11.9 years; left ventricular ejection fraction, 22.2+/-6.2%). Proton magnetic resonance spectroscopy data were obtained from localized regions ( approximately 8 mL) of the occipital gray matter and the parietal white matter. The primary end point was the occurrence of death after the proton magnetic resonance spectroscopy. During follow-up (18.5+/-14.4 months), 21 patients died and 15 underwent urgent heart transplantation. In the Cox proportional model, occipital metabolites (N-acetylaspartate, creatine, choline, and myoinositol), parietal N-acetylaspartate level, and the duration of CHF symptoms (>12 months) were validated as univariate predictors of death. In multivariate Cox analyses, however, the occipital N-acetylaspartate level was an independent predictor of death (hazard ratio, 0.52; 95% CI, 0.41 to 0.67; P<0.001). An analysis with respect to the combined end point of death or urgent transplantation showed similar results. The best cutoff value (9.0 mmol/kg) for occipital N-acetylaspartate level had 75% sensitivity and 67% specificity to predict mortality.

CONCLUSIONS

The occipital N-acetylaspartate level is a powerful and independent predictor of CHF mortality, suggesting that cerebral metabolic abnormalities may be used as a new prognostic marker in the assessment of patients with CHF.

Study on the Expression of Insulin-like Growth Factor II (IGF- II) in Hepatocellular Carcinoma Cells and Developing Rat Embryos

PURPOSE

The insulin-like growth factor II (IGF-II) gene expresses a family of transcripts in embryonic/fetal tissue, and also highly was expressed during hepatocellular carcinogenesis. In this study, we showed that IGF-II mRNA and protein levels are detected in rat embryo, HepG2 human hepatoma cells and Chang liver cells.

MATERIALS AND METHODS

This study included sections of rat embryos 7~17 days post coitum (d.p.c), HepG2 cells and Chang liver cells. Using immunohistochemistry, Northern blotting and Western blotting, we observed the expression of IGF-II in the rat embryo, HepG2 cells and Chang liver cells.

RESULTS

We localized IGF-II gene products in sections of rat embryo 7~17 d.p.c by performing immunohistochemistry. The IGF-II was mainly expressed in the proximal endoderm and ectoplacental cone between 7 and 9 d.p.c. At 10 d.p.c. the expression was localized at the heart primodium as well as the proximal endoderm, and at 11 d.p.c. the IGF-II was expressed in the liver and heart. After 12 d.p.c. and 14 d.p.c., the expression was also detected in the brain, muscle and bone, and head mesenchyme, respectively. While the expression of IGF-II protein was not detected in the normal adult liver, intense staining was detected in the heart, liver and choroids plexus at 17 d.p.c.

CONCLUSION

These results suggest that IGF-II may act as an oncofetal protein during hepatocellular carcinogenesis and embryogenesis.

Intraarticular entrapment of the obturator nerve in acetabular fracture

SUMMARY

The authors report a case of acetabular fracture of both columns that was associated with a rare nerve injury, entrapment of the obturator nerve in the hip joint.

MRI findings in neuro-behçet's disease

AIM

To evaluate the pattern and site of involvement in neuro-Behçet's disease (NBD).

MATERIALS AND METHODS

Twenty-one patients with NBD were evaluated. Using 1.5T magnetic resonance imaging (MRI), T1-weighted axial and sagittal images, gadolinium enhanced axial and coronal images and T2-weighted axial images were obtained.

RESULTS

The brainstem, basal ganglia, cerebral white matter, internal capsule, thalamus and spinal cord were involved in eighteen, nine, nine, seven, six and two patients, respectively. In nine patients with cerebral white matter involvement, four had subcortical involvement and three had periventricular involvement, in addition to two patients with focal deep white matter lesions. Among the brainstem lesions, pons involvement was seen in fourteen patients, all had ventrally located lesions, and nine had tegmental involvement. Midbrain involvement was seen in fourteen patients; the cerebral peduncle was involved in 11 of these. Five patients had brainstem atrophy: two cases were demonstrated at initial MRI, the other three cases were seen on follow-up MRI. Pyramidal signs, the most common neurological signs, were demonstrated in fourteen patients. Follow-up MRI was obtained 10 days to 20 months after the initial MRI in eight cases; all showed changes in size, shape and site of involvement. After gadolinium enhancement, thirteen patients demonstrated mottled non-confluent enhancement in the brainstem (eight patients), posterior limb of the internal capsule (three patients), pachymeninges (two patients) and spinal cord (two patients).

CONCLUSION

NBD manifests a reversible course, but chronic NBD may result in brainstem atrophy. Characteristic involvement along the corticospinal tract is well correlated with neurological signs.

The feasibility and safety of fluoroscopy-guided percutaneous intramyocardial gene injection in porcine heart

BACKGROUND

Catheter-based transendocardial gene injection would be useful for the delivery of genes into the heart. We examined the feasibility and safety of percutaneous intramyocardial gene injections with fluoroscopic guidance alone.

METHODS

We performed the procedure through an 8F arterial sheath inserted into the left carotid artery. In protocol 1, a mixture of India ink and normal saline was injected through a needle injection catheter in six pigs. We monitored blood pressure and ECG continuously during the procedure. Echocardiography, left ventriculography, and coronary angiography were performed. All pigs were sacrificed 2 days later and hearts were harvested. In protocol 2, a mixture of India ink and plasmid encoding CAT gene was injected in the same manner in eight pigs. Myocardial tissue was obtained 7 days after the procedure to assess gene expression. In protocol 3, four pigs were intentionally needle-perforated in the ventricular wall and were observed for 7 days.

RESULTS

In protocol 1, there was no significant hemodynamic changes or serious arrhythmias during the procedure. Echocardiography and angiography revealed no evidence indicating pericardial effusion or wall motion abnormalities. Harvested hearts revealed one intramyocardial hematoma in a total of 36 injection sites. In protocol 2, the gene expression could be identified in 39 sites out of 48 injections after 7 days. In protocol 3, no animal showed signs indicating cardiac tamponade during the observation period.

CONCLUSIONS

Our data suggest that fluoroscopy-guided percutaneous intramyocardial gene injection is a feasible and safe procedure, with no indication of associated significant hemodynamic changes, arrhythmias, or mortality.

Short peptides with induced beta-turn inhibit the interaction between HIV-1 gp120 and CD4

To identify novel peptides that inhibit the interaction between human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 and CD4, we constructed a targeted phage-displayed peptide library in which phenylalanine and proline were fixed at the fourth and sixth positions, respectively, because Phe43 and the adjacent beta-turn of CD4 are critical for interaction with gp120. Two synthetic peptides were selected after three rounds of biopanning against gp120, and one of them, G1 peptide (ARQPSFDLQCGF), exhibited specific inhibition of the interaction between gp120 and CD4 with an IC(50) of about 50 microM. Structural analysis using NMR demonstrated that G1 peptide forms a compact cyclic structure similar to the CD4 region interacting with gp120. Two derivatives of G1 peptide, a linear hexameric peptide (G1-6) and a cyclic nonameric peptide (G1-c), were synthesized based on the structure of the G1 peptide. Interestingly, they showed higher inhibitory activities than did G1 peptide with IC(50)'s of 6 and 1 microM, respectively. Thus, this study might provide a new insight into the development of anti-HIV-1 inhibitors.

Contribution of the Na+-K+-2Cl- cotransporter NKCC1 to Cl- secretion in rat OMCD

In rat kidney the "secretory" isoform of the Na+-K+-2Cl- cotransporter (NKCC1) localizes to the basolateral membrane of the alpha-intercalated cell. The purpose of this study was to determine whether rat outer medullary collecting duct (OMCD) secretes Cl- and whether transepithelial Cl- transport occurs, in part, through Cl- uptake across the basolateral membrane mediated by NKCC1 in series with Cl- efflux across the apical membrane. OMCD tubules from rats treated with deoxycorticosterone pivalate were perfused in vitro in symmetrical HCO/CO2-buffered solutions. Cl- secretion was observed in this segment, accompanied by a lumen positive transepithelial potential. Bumetanide (100 microM), when added to the bath, reduced Cl- secretion by 78%, although the lumen positive transepithelial potential and fluid flux were unchanged. Bumetanide-sensitive Cl- secretion was dependent on extracellular Na+ and either K+ or NH, consistent with the ion dependency of NKCC1-mediated Cl- transport. In conclusion, OMCD tubules from deoxycorticosterone pivalate-treated rats secrete Cl- into the luminal fluid through NKCC1-mediated Cl- uptake across the basolateral membrane in series with Cl- efflux across the apical membrane. The physiological role of NKCC1-mediated Cl- uptake remains to be determined. However, the role of NKCC1 in the process of fluid secretion could not be demonstrated.

Three-dimensional spiral CT cholangiography with minimum intensity projection in patients with suspected obstructive biliary disease: comparison with percutaneous transhepatic cholangiography

BACKGROUND

To evaluate the diagnostic potential of spiral computed tomographic (CT) cholangiography with minimum intensity projection (minIP) in the diagnosis of patients with suspected biliary obstruction.

METHODS

Nine consecutive patients with obstructive biliary disease were enrolled in this study. Spiral CT data (3-mm slice thickness, pitch 1-2:1) obtained 65 s after the start of contrast medium injection (150 mL Ultravist 370, 3 mL/s) were reconstructed at 1-mm intervals. Three-dimensional (3D) CT cholangiography with minIP (3D CTC) was generated with a Siemens software package. The quality of 3D CTC in its ability to demonstrate the anatomic detail, the level of obstruction, and the presence or absence of isolated hepatic segments was evaluated using percutaneous transhepatic cholangiography as a gold standard.

RESULTS

In all patients, 3D CTC demonstrated dilated intrahepatic ducts up to tertiary branches. 3D CTC correctly diagnosed the level of biliary obstruction and demonstrated isolated segments in all patients. In determining the cause of biliary obstruction, one patient with hilar cholangiocarcinoma was misdiagnosed as having biliary invasion by hepatocellular carcinoma.

CONCLUSION

3D CTC with minIP can determine the level and cause of biliary obstruction. 3D CTC can be obtained from regular thin-section helical CT data and may be a strong competitor against diagnostic magnetic resonance cholangiography because of its superior resolution and information on adjacent soft tissues and the duct itself.