Bcl-2 protects tubular epithelial cells from ischemia/reperfusion injury by dual mechanisms.

Ischemia/reperfusion (I/R) injury, which induces extensive loss of tubular epithelial cells, is associated with delayed graft function following kidney transplantation. Recent reports have suggested that cell death by I/R injury occurs by autophagy, a cellular degradation process responsible for the turnover of unnecessary or dysfunctional organelles and cytoplasmic proteins, as well as by apoptosis. Recently, we demonstrated that overexpression of the anti-apoptotic factor, Bcl-2, inhibited tubular apoptosis and subsequent tubulointerstitial damage after I/R injury. Autophagy is also observed in cells undergoing cell death in several diseases. Therefore, we hypothesized that increased Bcl-2 protein may protect tubular epithelial cells by suppressing autophagy and inhibiting apoptosis. In the present study, a transgenic mouse model (LC3-GFP TG) in which autophagosomes are labeled with LC3-GFP and Bcl-2/LC3-GFP double transgenic mice (Bcl-2/LC3-GFP TG) were used to examine the effect of Bcl-2 on I/R-induced autophagy. I/R injury, which is associated with marked disruption of normal tubular morphology, promoted the formation of LC3-GFP dots, representing extensively induced autophagosomes. On electron microscopy, the autophagosomes contained mitochondria in I/R-injured tubular epithelial cells. In contrast, Bcl-2 augmentation suppressed the formation of autophagosomes and there was less tubular damage. In conclusion, Bcl-2 augmentation protected renal tubular epithelial cells from I/R injury by suppressing autophagosomal degradation and inhibiting tubular apoptosis.

Superagonistic CD28 antibody induces donor-specific tolerance in rat renal allografts.

The ultimate goal of organ transplantation is to establish graft tolerance where CD4+CD25+FOXP3+ regulatory T (Treg) cells play an important role. We examined whether a superagonistic monoclonal antibody specific for CD28 (CD28 SA), which expands Treg cells in vivo, would prevent acute rejection and induce tolerance using our established rat acute renal allograft model (Wistar to Lewis). In the untreated or mouse IgG-treated recipients, graft function significantly deteriorated with marked destruction of renal tissue, and all rats died by 13 days with severe azotemia. In contrast, 90% of recipients treated with CD28 SA survived over 100 days, and 70% survived with well-preserved graft function until graft recovery at 180 days. Analysis by flow cytometry and immunohistochemistry demonstrated that CD28 SA induced marked infiltration of FOXP3+ Treg cells into the allografts. Furthermore, these long-surviving recipients showed donor-specific tolerance, accepting secondary (donor-matched) Wistar cardiac allografts, but acutely rejecting third-party BN allografts. We further demonstrated that adoptive transfer of CD4+CD25+ Treg cells, purified from CD28 SA-treated Lewis rats, significantly prolonged allograft survival and succeeded in inducing donor-specific tolerance. In conclusion, CD28 SA treatment successfully induces donor-specific tolerance with the involvement of Treg cells, and thus the therapeutic value of this approach warrants further investigation and preclinical studies.

Expression of polymorphonuclear leukocyte adhesion molecules and its clinical significance in patients treated with percutaneous transluminal coronary angioplasty.

OBJECTIVES: This study evaluated the role of neutrophil adhesion molecules LFA-1 (CD11a/CD18), Mac-1 (CD11b/CD18) and p150,95 (CD11c/CD18) in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Several recent studies have suggested that cell adhesion molecules on both neutrophils and vascular endothelial cells play an important role in the process of tissue inflammation. METHODS: Thirty-eight patients (30 men, 8 women; mean [+/-SE] age 56 +/- 5 years, range 38 to 76) with single-vessel coronary artery disease of the left anterior descending artery underwent coronary angioplasty. Peripheral blood was sampled at baseline before, immediately after and 12, 24, 48 and 144 h after PTCA. The expression of CD18, CD11a, CD11b and CD11c on the surface of polymorphonuclear leukocytes was examined by flow cytometry with monoclonal antibodies. RESULTS: In patients without subsequent restenosis, there was no change in mean channel fluorescence intensity (MFI) of CD18 at each sampling time. However, in the patients with restenosis, the MFI of CD18 significantly increased at 48 h after PTCA (from 57 +/- 6 to 73 +/- 8, p = 0.0008). The MFI of CD11b increased slightly at 48 h after PTCA in patients without restenosis (from 584 +/- 121 to 735 +/- 114, p = 0.037). In patients with restenosis, the MFI of CD11b was slightly increased at 24 h after PTCA (from 586 +/- 122 to 768 +/- 214, p = 0.018) and significantly increased at 48 h after PTCA (to 1,534 +/- 268, p = 0.0006). The expression of CD11a and CD11c did not change at any sampling points after PTCA in either of the two patient groups. Percent change in the expression of CD18 at 48 h after PTCA (from baseline) and that of CD11b were correlated (r = 0.73, p = 0.0008) in patients with restenosis. CONCLUSIONS: Inflammatory stimuli within the coronary vessels associated with coronary angioplasty may upregulate Mac-1 expression on the surface of polymorphonuclear leukocytes. This process may be more marked in patients who experience later restenosis. Thus, activation of neutrophil adhesion molecule Mac-1 at 48 h after PTCA may have value as a predictor of subsequent restenosis.

Conserved and divergent expression of T-box genes Tbx2-Tbx5 in Xenopus.

We report here the identification of four members of T-box family genes, Xltbx2-Xltbx5, in Xenopus. Two of them are probable pseudovariant genes of XTbx5 and ET, a putative Xenopus ortholog of Tbx3. We compared their expression patterns in both embryos and limbs. In embryos, expression of Xltbx2 and Xltbx3 showed novel diversities, such as Xltbx2 in the neural crest cells and Xltbx3 in the ventral spinal cord, together with mutual similarities in the following regions: dorsal retina, proctoderm, lateral line organ, cement gland and cranial ganglia. The patterns in limbs were highly conserved with mouse and chick orthologs, including the limb-type specific expression of Xltbx4 and Xltbx5. In addition, RT-PCR analysis showed that they are expressed weakly even in adult limbs as previously reported in the newt.

Distinct expression of two types of Xenopus Patched genes during early embryogenesis and hindlimb development.

Patched (Ptc) is a putative twelve transmembrane domain protein that is both a Hedgehog (Hh) receptor and transcriptional target of Hh. In this study, we isolated Xenopus Ptc cDNAs, Ptc-1 and Ptc-2, and carried out comparative analyses on their expression patterns. The putative Ptc-2 protein has a long C-terminal extension that has similarities in both length and sequence to those of Ptc-1 proteins in mouse, chick and human. In both early embryogenesis and hindlimb development, Ptc-2 expression is restricted to cells that receive a Hh signal, a pattern similar to that of Gli-1. Ptc-1, however, shows a broader distribution, mainly non-overlapping with that of Ptc-2. Despite the difference in their expression patterns, both are induced in animal cap explants synergistically by Shh and Noggin, showing a conserved regulation in their activation mechanisms.

Emergent photovoltage on SmB6 surface upon bulk-gap evolution revealed by pump-and-probe photoemission spectroscopy.

Recent studies suggest that an exemplary Kondo insulator SmB6 belongs to a new class of topological insulators (TIs), in which non-trivial spin-polarized metallic states emerge on surface upon the formation of Kondo hybridization gap in the bulk. Remarkably, the bulk resistivity reaches more than 20 Ω cm at 4 K, making SmB6 a candidate for a so-called bulk-insulating TI. We here investigate optical-pulse responses of SmB6 by pump-and-probe photoemission spectroscopy. Surface photovoltage effect is observed below ~90 K. This indicates that an optically-active band bending region develops beneath the novel metallic surface upon the bulk-gap evolution. The photovoltaic effect persists for >200 µs, which is long enough to be detected by electronics devices, and could be utilized for optical gating of the novel metallic surface.

Antihypertensive effects of cicletanine and renal protection in Dahl salt-sensitive rats.

We designed experiments to reveal the antihypertensive properties of cicletanine, a novel antihypertensive drug, in Dahl salt-sensitive (Dahl-S) rats. Cicletanine (39 mg/kg body weight per day for 6 weeks) ameliorated the development of hypertension in Dahl-S rats fed a high-salt (4% NaCl) diet. This blood pressure reduction was associated with a decrease in heart weight and vascular wall thickness. Moreover, urinary prostacyclin (PGl2) excretion was increased with cicletanine treatment, being inversely related to systolic blood pressure. Proteinuria and urinary excretion of n-acetyl-beta-D-glucosaminidase were decreased and glomerular filtration rate was increased with this treatment. Morphological investigation revealed an improvement in glomerulosclerosis, renal tubular damage and intrarenal arterial injury in the salt-induced hypertensive rats. In contrast, trichloromethiazide, which decreased blood pressure to the same extent as cicletanine, lowered urinary PGl2 excretion and generally did not ameliorate the deteriorated renal functions and morphological abnormalities. Thus, these data indicate that cicletanine ameliorates the development of hypertension in Dahl-S rats and protects the cardiovascular and renal systems against the injuries seen in the hypertension. The enhanced vasodepressor PGl2 synthesis probably participates, to some extent, in these beneficial properties of long-term cicletanine treatment.

Immunohistochemical expression of human chorionic gonadotropin and P-glycoprotein in human pituitary glands and craniopharyngiomas.

In order to clarify the cellular origin of craniopharyngiomas, the authors examined the distribution of P-glycoprotein (PGP) and human chorionic gonadotropin (HCG) in five normal adenohypophyses and in 23 craniopharyngiomas using peroxidase immunohistochemistry. The correlation between the expression of PGP in craniopharyngiomas and the recurrence of these tumors was also investigated. A number of pars intermedia cyst-lining cells immunostained positively for anti-PGP antibodies. A small number of adenohypophysial cells were also positive for PGP, but squamous epithelial nests were negative in all samples. However, HCG-beta was consistently demonstrated in adenohypophysial cells, pars intermedia cyst-lining cells, and squamous epithelial nests. In 11 craniopharyngiomas, the apical portion of cuboidal cells and some polygonal cells immunostained positively with anti-PGP antibodies. In four HCG-producing craniopharyngiomas, a large number of tumor cells were immunostained with anti-PGP antibodies, three of which showed a recurrence of cystic tumors. By double labeling, the coexpression of HCG-beta and PGP was demonstrated in these recurrent tumors. Accordingly, it is suggested that craniopharyngiomas produce HCG-like peptides and that craniopharyngiomas are unique squamous neoplasms arising in the sellar region from progenitor cells of a neuroendocrine lineage.

P-glycoprotein as the drug efflux pump in primary cultured bovine brain capillary endothelial cells.

The expression of a functional P-glycoprotein (P-gp) which pumps drugs out of brain capillary endothelial cells (BCEC) into blood was studied by evaluating the steady-state uptake and efflux of vincristine (VCR) by primary cultured bovine BCEC. The steady-state uptake of VCR was increased in the presence of metabolic inhibitors, and an anti-P-gp monoclonal antibody, MRK16, as well as verapamil and steroid hormones which are known to reverse multidrug resistance in tumor cells. Furthermore, efflux of VCR from BCEC was inhibited by verapamil. By immunohistochemistry, P-gp was localized at the luminal side of the capillary endothelial cells in both gray matter of bovine brain and primary cultured BCEC. These data suggest that P-gp functions as a drug efflux pump at the luminal side of BCEC and regulates the transfer of certain lipophilic drugs from the blood into the brain.

Plasma thrombomodulin levels in coronary sinus blood in patients with coronary artery disease.

Plasma thrombomodulin (TM) levels in coronary sinus blood were measured in 15 patients with coronary artery disease who underwent elective PTCA (group A). TM was also measured in eight patients with coronary artery disease (group B) and six patients without coronary artery disease (group C), who only underwent diagnostic coronary angiography. The baseline level was 21.6 +/- 3.4 U/ml in group A, and 21.0 +/- 4.9 in group B, and both levels were slightly higher (P < 0.05) than those in group C (15.1 +/- 3.3). In group A, the level increased to 27.5 +/- 8.3 (P < 0.01) immediately after PTCA and then returned to 22.2 +/- 5.1 by 24 h. In groups B and C, levels showed no change immediately after angiography. In group A, the percentage increase in the TM level immediately after PTCA from that before the procedure correlated with the number of balloon inflations (r = 0.76, P < 0.01). In conclusion, the plasma TM level in coronary sinus blood might indicate endothelial damage due to atherosclerotic coronary artery disease and an increase in the level after PTCA might directly indicate vascular injury by balloon inflation.

Relationship between regional abnormality of left ventricular rapid filling and coronary microcirculation disturbance in hypertrophic cardiomyopathy.

BACKGROUND AND HYPOTHESIS: To investigate the mechanism of regional left ventricular diastolic filling disturbance in hypertrophic cardiomyopathy (HCM), we assessed the relationship between abnormalities of regional ventricular rapid filling and regional coronary microcirculation using radionuclide ventriculography and exercise 201thallium (201TI) myocardial scintigraphy with sector analysis. METHODS: Thirty patients with HCM and 14 patients with atypical chest pain syndrome (controls) were studied. Left ventricular images (left anterior oblique view) were obtained by electrocardiogram-gated 99mtechnetium radionuclide angiography and were divided into three sectors radiating from the geometric center. The time-activity curves and their first derivative curves were analyzed, and the peak filling rate (PFR), the ratio of the time-to-peak filling rate per diastolic interval (TPFR/T) were calculated for the global left ventricle and for the lateral and septal sectors. Exercise stress 201TI myocardial scintigraphy was also performed, and early and delayed images were obtained. The regional washout rate (WR) was then evaluated for the lateral and septal sectors. RESULTS: In HCM patients, the regional PFR in the septal sector (corresponding to the region of hypertrophic myocardium) was 285 +/- 76%/s, and was significantly lower than that in the controls (398 +/- 90%/s, p < 0.01). The regional TPFR/T in the septal sector (32 +/- 10%) was prolonged compared with the value of 21 +/- 5% in the controls (p < 0.05). The regional WR in the septal sector was 21 +/- 9%, and was significantly lower than that in the controls (43 +/- 5%, p < 0.01). Moreover, regional WR correlated positively with regional PFR (r = 0.5, p < 0.05) and showed a weak negative relationship with regional TPFR/T (r = -0.4, p < 0.07) in the septal sector. CONCLUSIONS: These results suggest that regional impairment of rapid filling might be related to a disturbance of the coronary microcirculation in HCM.

Hemofiltration as treatment for patients with refractory heart failure.

Hemofiltration was performed in 15 patients with refractory congestive heart failure. All of these patients had oliguria, although intensive treatment with diuretics, digitalis, vasodilators, and catecholamines was prescribed. Hemofiltration was performed under hemodynamic monitoring in 14 patients. The water removal by hemofiltration decreased pulmonary arterial pressure, pulmonary capillary wedge pressure and right atrial pressure. Despite these hemodynamic improvements, nine patients (60%) died within one month after the start of hemofiltration; the causes were fatal arrhythmia in three, renal failure in two, sepsis in one and irreversible cardiogenic shock in three. Oliguria for over 15 h or a serum creatinine concentration of more than 4.0 mg/dl at the start of hemofiltration related to poor prognosis. In view of these results, hemofiltration for refractory heart failure should be started earlier and performed carefully in order to avoid arrhythmia, cardiogenic shock, and other complications.

Left ventricular diastolic dysfunction in coronary artery disease: effects of coronary revascularization.

Left ventricular diastolic dysfunction was studied globally and regionally in patients with coronary artery disease, and the effects of coronary revascularization were evaluated. A total of 25 patients with angina pectoris who had a stenotic lesion (greater than or equal to 90%) in only left anterior descending branch underwent coronary revascularization [percutaneous transluminal coronary angioplasty (PTCA) in 13 patients and coronary artery bypass graft (CABG) in 12]. Nine patients with normal coronary artery were studied as controls. Left ventricular volume and radial axes were measured on serial frames of one cardiac cycle by cine left ventriculography. The radial axes were drawn from the left ventricular gravity to left ventricular wall at every 20 degrees. Left ventricular filling fraction and distension rate of radial axes were calculated at the times of 25%, 50%, 75%, and 100% of diastolic period, 100% being end-diastole. Although there were no significant changes of the systolic function by revascularization, the filling fraction increased from 11.2 +/- 2.6 to 14.5 +/- 3.5% (p less than 0.001) at 25% time of diastole, from 29.9 +/- 4.9 to 32.5 +/- 5.0% (p less than 0.05) at 50% time in the PTCA group, and from 11.8 +/- 3.7 to 13.4 +/- 3.8% (p less than 0.01) at 25% time in the CABG group. The distension rate of radial axis to the anterior wall also increased significantly at 25% and 50% time of diastole after revascularization, and the change was marked in the PTCA group. However, these increases did not apply to the control patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular diastolic filling in patients with coronary artery disease without myocardial infarction.

Left ventricular diastolic dysfunction at rest was studied in 24 patients with coronary artery disease but no evidence of previous myocardial infarction. Seven patients with normal coronary arteries were studied as control. Diastolic filling was analyzed by the serial left ventricular volume and 14 radial axes from the gravity point of the left ventricle with cine left ventriculography. There were no differences in the systolic function between coronary artery disease and the normal control. Peak filling rate was decreased significantly in the groups with left anterior descending artery disease (LAD, p less than 0.05) and multivessel disease (MVD, p less than 0.05), but not in the group with right coronary artery disease (RCA). Time to peak filling rate was prolonged in each group of LAD (p less than 0.05), RCA (p less than 0.05), and MVD (p less than 0.001), compared with controls. The time-volume curve showed disturbed rapid filling in the LAD and RCA groups, and also both depressed rapid and slow filling in the MVD group. In the LAD group, the filling fraction was decreased significantly at the time of 25% of the diastolic period (p less than 0.001) and radial distension to the anterior wall was decreased at the time of 25%, 50%, and 75% of the diastolic period, compared with controls. In the RCA group, the filling fraction (p less than 0.001) and radial distension to the posterior wall were decreased only at the time of 25% of the diastolic period. In the MVD group, filling fraction and radial distension to the most wall were decreased at 25%, 50%, and 75% of the diastolic period.(ABSTRACT TRUNCATED AT 250 WORDS)

Global and regional abnormalities of left ventricular diastolic filling in hypertrophic cardiomyopathy.

Left ventricular diastolic filling was studied by left ventriculography in 17 patients with hypertrophic cardiomyopathy (HCM). In 8 patients this manifested as a spadelike shape (HCM-S type) on the left ventriculogram, and in 9 patients as a banana shape (HCM-B type). Seven patients were studied as controls. Left ventricular end-diastolic pressure was higher in HCM than in controls. In HCM, peak filling rate was decreased from 1.57 +/- 0.28 of the control to 1.28 +/- 0.20 (p less than 0.05), and the time to peak filling rate was prolonged from 27 +/- 6%DT of the control to 37 +/- 7%DT (p less than 0.01). Serial volume analysis in diastole showed filling fraction was also significantly decreased to 8.2 +/- 4.1 (p less than 0.001) at the 25% diastole time and 29.6 +/- 7.2 (p less than 0.01) at half time, compared with 19.8 +/- 6.3 and 32.8 +/- 5.8 for controls, respectively. In HCM-S type, the rate of distention of left ventricular radial axes at the apical area was lower at early and mid-diastole. In HCM-B type, the rate at the basal area was lower at early and mid-diastole. Results suggest that the left ventricular diastolic filling in HCM was impaired not uniformly but regionally in the hypertrophic area at early and mid-diastole.

Right-to-left shunting through a patent foramen ovale caused by pulmonary hypertension associated with rheumatoid arthritis and Sjögren's syndrome: a case report.

This case report presents a fifty-four-year-old woman with right-to-left shunt in the atrium. It seemed clinically at first that the shunt was due to atrial septal defect. However, she also had pulmonary disease associated with rheumatoid arthritis and Sjögren's syndrome. At autopsy atrial septal defect was not evident, but a patent foramen ovale and pulmonary artery disease were observed. This case suggests that pulmonary hypertension secondary to rheumatoid arthritis and Sjögren's syndrome could lead to right-to-left shunting through a patent foramen ovale.

The size of kidney with renovascular hypertension in patients with aortitis syndrome.

Renal atrophy due to the renal artery stenosis associated with aortitis syndrome was studied in seven patients. Severe hypertension, high plasma renin activity and normal overall renal functions were present in all. The luminal diameter of the stenosed renal artery seen on the angiogram was less than 1.5 mm at the maximum area of stenosis in all patients. The size of the kidney with renal artery stenosis was diminished, ranging from 8.0 to 14.0 cm in longitudinal diameter on the nephrogram. Histological findings of the small kidney revealed ischemic atrophy. Although the rate of progression of the arterial stenosis was uncertain, the collateral circulation was found to be rich. Renal atrophy was not frequent and not marked even in the presence of high grade renal stenosis or obstruction in case of renovascular hypertension secondary to the arteritis.

Coronary artery aneurysms and congestive heart failure--possible long-term course of Kawasaki disease in an adult--a case report.

Multiple coronary artery aneurysms, rarely seen in patients with atherosclerotic heart disease, can be frequently observed in children with Kawasaki disease. However, their long-term clinical courses still remain obscure. A thirty-nine-year-old male came to our clinic because of congestive heart failure. A left ventriculogram revealed highly reduced wall motion. A coronary angiogram showed left main trunk aneurysm with complete occlusion of the left anterior descending artery and ramification of the right coronary artery close to the ostium. Six months after discharge, he died suddenly. On autopsy, aneurysms were observed in the left main trunk and right coronary artery, together with an old anteroseptal myocardial infarction. Although he did not have a clear history of febrile disease in childhood, he was highly suspected to be a long-term survivor of Kawasaki disease because of the unique form and distribution of the coronary artery aneurysms.

Features of coronary artery lesions related to left ventricular aneurysm formation in anterior myocardial infarction.

To determine the factors of left ventricular aneurysm formation in acute myocardial infarction, the authors studied the distribution of coronary artery lesions and the left ventricular wall motion of 43 patients with anterior myocardial infarction. Of 15 patients with aneurysm, 9 (60%) showed a single-vessel disease with severe stenosis of the proximal left anterior descending artery. Of 9 patients with triple-vessel disease, 8 (89%) had no aneurysm. In patients with the aneurysm, the Gensini score of the culprit lesion was significantly higher (p < 0.05) and the score except for the culprit lesion was less (chi 2 = 5.7, p < 0.05). In 23 patients with single-vessel disease, the collateral score was significantly less (p < 0.05) in patients with the aneurysm. The systolic wall motion on the ventriculogram appeared more impaired in the anterior infarct area but well maintained in the posterior noninfarct area in patients with the aneurysm. In conclusion, the important factors of left ventricular aneurysm formation were as follows: (1) A culprit lesion of the myocardial infarction was severe, but other coronary artery lesions were mild. (2) Collateral vessels were poor. (3) The left ventricular wall motion of the infarct area was impaired, but that of the noninfarct area was relatively good.

Survival from acute occlusion of the left main coronary artery with preexisting collateral vessels--a case report.

A thirty-two-year-old man suffered from evolving acute myocardial infarction caused by total occlusion of the left main coronary artery, which was 95% stenosed before the onset. Nevertheless, he had a good clinical course. The myocardium may have been protected by well-developed preexisting collateral vessels as evidenced by serial coronary angiograms.