Sex-Driven Differences in the Effectiveness of Individualized Clinical Management of Alzheimer's Disease Risk

BACKGROUND

The Comparative Effectiveness Dementia and Alzheimer's Registry (CEDAR) trial demonstrated that individualized, multi-domain interventions improved cognition and reduced the risk of Alzheimer's disease (AD). As biological sex is a significant risk factor for AD, it is essential to explore the differential effectiveness of targeted clinical interventions in women vs. men.

METHODS

Patients were recruited from an Alzheimer's Prevention Clinic. Subjects with normal cognition, subjective cognitive decline, or asymptomatic preclinical AD were classified as "Prevention". Subjects with mild cognitive impairment due to AD or mild AD were classified as "Early Treatment." The primary outcome was the change from baseline to 18-months on the modified-Alzheimer's Prevention Cognitive Composite. Secondary outcomes included a cognitive aging composite, AD and cardiovascular (CV) risk scales, and serum biomarkers. Subjects who adhered to > 60% of recommendations in the CEDAR trial were included in this a priori sub-group analysis to examine whether individualized intervention effects were modified by sex (n=80).

RESULTS

In the Prevention group, both women (p=0.0205) and men (p=0.0044) demonstrated improvements in cognition with no sex differences (p=0.5244). In the Early Treatment group, there were also no significant sex differences in cognition (p=0.3299). In the Prevention group, women demonstrated greater improvements in the Multi-Ethnic Study of Atherosclerosis risk score (MESA-RS) than men (difference=1.5, p=0.0013). Women in the Early Treatment group demonstrated greater improvements in CV Risk Factors, Aging and Incidence of Dementia (CAIDE) risk score (difference=2.3, p=0.0067), and the MESA-RS (difference=4.1, p<0.001).

CONCLUSIONS

Individualized multi-domain interventions are equally effective at improving cognition in women and men. However, personally-tailored interventions led to greater improvements in calculated AD and CV risk, and CV blood biomarkers, in women compared to men. Future study in larger cohorts is necessary to further define sex differences in AD risk reduction in clinical practice.

Open-label phase II study of the efficacy of nivolumab for cancer of unknown primary

BACKGROUND

Cancer of unknown primary (CUP) has a poor prognosis. Given the recent approval of immune checkpoint inhibitors for several cancer types, we carried out a multicenter phase II study to assess the efficacy of nivolumab for patients with CUP.

PATIENTS AND METHODS

Patients with CUP who were previously treated with at least one line of systemic chemotherapy constituted the principal study population. Previously untreated patients with CUP were also enrolled for exploratory analysis. Nivolumab (240 mg/body) was administered every 2 weeks for up to 52 cycles. The primary endpoint was objective response rate in previously treated patients as determined by blinded independent central review according to RECIST version 1.1.

RESULTS

Fifty-six patients with CUP were enrolled in the trial. For the 45 previously treated patients, objective response rate was 22.2% [95% confidence interval (CI), 11.2% to 37.1%], with a median progression-free survival and overall survival of 4.0 months (95% CI, 1.9-5.8 months) and 15.9 months (95% CI, 8.4-21.5 months), respectively. Similar clinical benefits were also observed in the 11 previously untreated patients. Better clinical efficacy of nivolumab was apparent for tumors with a higher programmed death-ligand 1 expression level, for those with a higher tumor mutation burden, and for microsatellite instability-high tumors. In contrast, no differences in efficacy were apparent between tumor subgroups based on estimated tissue of origin. Adverse events were consistent with the known safety profile of nivolumab. No treatment-related death was observed.

CONCLUSIONS

Our results demonstrate a clinical benefit of nivolumab for patients with CUP, suggesting that nivolumab is a potential additional therapeutic option for CUP.

REVERCE: a randomized phase II study of regorafenib followed by cetuximab versus the reverse sequence for previously treated metastatic colorectal cancer patients

BACKGROUND

The objective of this randomized phase II trial was to evaluate efficacy and safety of the therapeutic sequence of regorafenib followed by cetuximab, compared with cetuximab followed by regorafenib, as the current standard sequence for metastatic colorectal cancer patients.

PATIENTS AND METHODS

Patients with KRAS exon 2 wild-type metastatic colorectal cancer after failure of fluoropyrimidine, oxaliplatin, and irinotecan were randomized to receive sequential treatment with regorafenib followed by cetuximab ± irinotecan (R-C arm), or the reverse sequence [cetuximab ± irinotecan followed by regorafenib (C-R arm)]. The primary end point was overall survival (OS). Key secondary end points included progression-free survival (PFS) with initial treatment (PFS1), PFS with second treatment (PFS2), safety, and quality of life. Exploratory end points included serial biomarker analyses, including oncogenic alterations from circulating tumor DNA or multiple serum or plasma proteins.

RESULTS

One-hundred one patients were randomized and eligible for efficacy analysis. Sequential treatment was successful in 86% patients in both arms. Median OS for R-C and C-R was 17.4 and 11.6 months, respectively (P = 0.0293), with a hazard ratio (HR) of 0.61 for OS [95% confidence interval (CI) 0.39-0.96]. The HR for PFS1 (regorafenib in R-C versus cetuximab in C-R) was 0.97 (95% CI 0.61-1.54), and PFS2 (C in R-C versus R in C-R) was 0.29 (95% CI 0.17-0.50). No unexpected safety signals were observed. The quality of life scores during the entire treatment period was not significantly different between the two arms. Circulating biomarker analyses showed emerging oncogenic alterations in RAS, BRAF, EGFR, HER2, and MET, which were more commonly detected after cetuximab than after regorafenib.

CONCLUSIONS

The therapeutic sequence of regorafenib followed by cetuximab suggests a longer OS than the current standard sequence.

Nanogel-based nasal ghrelin vaccine prevents obesity

Obesity is associated with multiple comorbidities such as cardiovascular diseases and has a huge economic impact on the health-care system. However, the treatment of obesity remains insufficient in terms of efficacy, tolerability, and safety. Here we created a nasal vaccine against obesity for the first time. To avoid the injectable administration-caused pain and skin-related adverse event, we focused on the intranasal route of antigen delivery. We developed a vaccine antigen (ghrelin-PspA (pneumococcal surface protein A)), which is a recombinant fusion protein incorporating ghrelin, a hormone that stimulates food intake and decreases energy expenditure, and PspA, a candidate of pneumococcal vaccine as a carrier protein. Ghrelin-PspA antigen was mixed with cyclic di-GMP adjuvant to enhance the immunogenicity and incorporated within a nanometer-sized hydrogel for the effective antigen delivery. Intranasal immunization with ghrelin-PspA vaccine elicited serum immunoglobulin G antibodies against ghrelin and attenuated body weight gain in diet-induced obesity mice. This obesity-attenuating effect was caused by a decrease in fat accumulation and an increase in energy expenditure that was partially due to an increase in the expression of mitochondrial uncoupling protein 1 in brown adipose tissue. The development of this nasal vaccine provides a new strategy for the prevention and treatment of obesity.

Liposome chaperon in cell-free membrane protein synthesis: one-step preparation of KcsA-integrated liposomes and electrophysiological analysis by the planar bilayer method

Chaperoning functions of liposomes were investigated using cell-free membrane protein synthesis.

Effective CpG DNA delivery using amphiphilic cycloamylose nanogels

Unmethylated CpG oligodeoxynucleotides induce inflammatory immune responses through cytokine production and have attracted increasing attention as an immunostimulator. However, there remains a challenging issue of the use of 'native CpG DNA'. In the present study, we prepared cationic nanometer-sized gels (nanogels) consisting of cycloamylose modified with cholesterol and diethylaminoethane to form hydrophobic cross-linking points and to add positively charged groups, respectively. The cationic nanogels and native CpG DNA formed nanometer-sized complexes. Complexes of native CpG DNA with cationic nanogels delivered native CpG DNA to macrophage-like cells and induced cytokine production. In addition, complexes of negative control oligonucleotides with cationic nanogels did not induce cytokine production, and the induction of cytokines using complexes of phosphorothioate-modified CpG with cationic nanogels was lower than that of native CpG DNA. These results suggest that the complex of native CpG DNA with cationic nanogels is a promising strategy for nucleic acid adjuvants.

New analysis of the hypertension mechanism in bevacizumab-treated patients using 3-tesla dynamic contrast-enhanced magnetic resonance imaging

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Background: Vascular endothelial growth factor (VEGF) signaling inhibitors, such as bevacizumab (BV), leads to endothelial dysfunction and microvascular rarefaction in noncancer tissue. Angiotensin II has been reported to induce VEGF production by inhibiting VEGF, but the reasons for activation of angiotensin II are unclear. We conducted a study to examine the relationship between renin-angiotensin axis and renal blood perfusion using dynamic contrast magnetic resonance imaging (DCE-MRI) in colorectal cancer patients.

Methods: Sixteen patients with colorectal cancer were enrolled. They received BV+FOLFIRI regimen as second line. DCE-MRI was performed before the treatment and after 12th courses. Renin, angiotensin I, angiotensin II and aldosterone were examined before treatment and at 3, 5, 8, 12th courses. DCE-MRI parameters, Area under the time-intensity curve over the first 90 seconds after injection of contrast material (AUC90) and volume transfer constant of contrast material (Ktrans, Kep) were calculated in the normal kidney and examine the correlation with renin-angiotensin axis.

Results: All DCE-MRI parameters decreased significantly after 12th courses compared with before treatment (Variables median: Ktrans -1.51, Kep -2.30, AUC90 -26.0, P < 0.001, all). A decrease in Kep correlated with higher renin, angiotensin I and angiotensin II (renin: P =0.001, angiotensin I: P =0.003, angiotensin II: P =0.002, respectively). A decrease in AUC90 correlated with higher aldosterone (P =0.005). Blood pressure did not correlate with each DCE-MRI parameters.

Conclusions: VEGF inhibition decreases vessel permeability and raises interstitial pressure in normal kidney. Our data suggest that renin-angiotensin axis is also one mechanism of hypertension caused by BV.

No significant financial relationships to disclose.

Single molecular mechanics of a cholesterol-bearing pullulan nanogel at the hydrophobic interfaces

The study of nanogel (hydrogel nanoparticle) has intensified in the last decade due to the enormous potential applications in biomimetics, biosensors, artificial muscles and drug delivery (or release) systems. Cholesterol-bearing pullulan (CHP) is composed of hydrophilic pullulan backbone and partly substituted hydrophobic cholesterol, and is capable of forming a stable hydrogel nanoparticle in aqueous solution due to the self-assembly of hydrophobic cholesterol moieties. The conformation of CHP changes dramatically at the hydrophobic interfaces. In order to understand the interfacial responses of CHP, the interaction forces of CHP nanogels to the hydrophobic HOPG (highly orientated pyrolytic graphite) or carbon-coated surfaces were measured using atomic force microscope. The freely jointed china model for CHP molecular elasticity was applied to the force-extension curves and debonding force-pull-off distance in order to estimate the contour lengths and the segment lengths of the CHP molecules. The segment length of CHP chains in aqueous solution was estimated 0.32+/-0.19 nm showing a very flexible chain. From our analysis of the dynamic force measurements, the debonding forces were shown to depend on the applied loading forces. The zero kinetic off-rate K(off)(0) and the transition state x(b) were estimated to be 1.1 x 10(-3)s(-1) and 2.9A, respectively.

Changes in left ventricular end-diastolic area, end-systolic wall stress, and fractional area change during anesthetic induction with propofol or thiamylal

PURPOSE

To elucidate the mechanisms of the more profound hypotensive effects of propofol relative to thiamylal, we monitored changes in left ventricular (LV) preload, afterload, and contractility during the course of anesthetic induction with propofol and thiamylal.

METHODS

Thirty-two patients (ASA I) were randomly assigned into two groups and injected with propofol (2 mg.kg(-1)) or thiamylal (4 mg.kg(-1)) as anesthetic induction agents. Transthoracic echocardiography (TTE) was used to assess LV performance before and during induction by the two anesthetics. The LV end-diastolic area (EDA) and LV end-systolic wall stress (ESWS) were used as indices of LV preload and LV afterload, respectively, while LV contractility was assessed by the fractional area change (FAC).

RESULTS

Both propofol and thiamylal significantly reduced EDA and ESWS without significant change in FAC. Propofol-induced reductions in EDA and ESWS were significantly greater than those of thiamylal.

CONCLUSION

The more profound hypotension observed during induction of anesthesia with propofol is due to the greater decrease in preload and afterload than with thiamylal, but not to a decrease in LV contractility.

Effect of coronary artery bypass grafting with gastroepiploic artery on gastric intramucosal pH and systemic inflammation

BACKGROUND

The purpose of this study was to investigate the effect of coronary arterial bypass grafting (CABG) with gastroepiploic artery (GEA) on gastric intramucosal pH and systemic inflammation.

METHODS

DESIGN

retrospective study.

SETTING

University hospital.

PARTICIPANTS

22 patients underwent CABG.

INVESTIGATIONS

the GEA group (n=13) received CABG with the GEA graft. The non-GEA group (n=9) received conventional CABG without the GEA graft.

MEASUREMENTS

gastric intramucosal pH (pHi) and carbon dioxide tension (PrCO(2)) were assessed by capnometric air tonometry. The difference between PrCO(2) and PaCO(2), PCO(2)-gap, was also determined. Systemic inflammatory responses were evaluated by serum interleukin-6 (IL-6) and leucocyte counts. Hemodynamics, oxygen delivery index (DO(2)I) and uptake index (VO(2)I) were monitored with catheters in the radial and pulmonary arteries (thermodilution).

RESULTS

The duration of aortic cross-clamping and cardiopulmonary bypass was similar in both groups. Both groups did not show any significant difference in gastric pHi, PCO(2)-gap, systemic inflammation and hemodynamics.

CONCLUSIONS

Our findings suggest that CABG using the GEA graft does not disturb gastric mucosal perfusion, and that laparotomy for the GEA graft does not aggravate systemic oxygen demand-supply imbalance or systemic inflammatory responses induced by hypothermic CPB. CABG with the GEA graft does not seem to pose an additional risk and is a safe technique compared with conventional CABG with regard to pHi and systemic inflammation.

Reduction of carotid artery blood flow in pediatric patients with syncope: evaluation with head-up tilt test

We investigated the effect of postural changes on cerebral circulation by measuring carotid artery blood flow (CABF) in the supine position and during head-up tilt (HUT) test using a Doppler flow meter. Subjects included 10 patients with neurally mediated syncope, 10 patients with orthostatic intolerance, 8 with epilepsy, aged between 8 to 24 years (mean +/- SD, 13.9 +/- 4.1 years). The test caused pallor and dizziness in 16 patients (symptomatic), while no symptoms were recognized in the other 12 patients (asymptomatic). Significant reductions in the mean CABF (Fm), maximum CABF (Fs) and minimum CABF (Fd), components of the CABF waveform, were noticed during HUT compared to before HUT (supine), and these reductions in symptomatic patients were more severe than those in asymptomatic patients (Fm: - 2.8 +/- 2.0 SD vs - 0.7 +/- 1.4 SD; Fs: - 2.7 +/- 1.5 SD vs - 0.9 +/- 1.3 SD; Fd: - 4.5 +/- 2.8 SD vs - 2.2 +/- 2.1 SD). Reductions in Fm, Fs and Fd in the symptomatic patients during HUT lasted longer than those of the asymptomatic patients, being statistically significant for Fm and Fs (Fm: p < 0.01; Fs: p < 0.05). The criteria during HUT for distinguishing neurally mediated syncope (NMS) from others was Fs: < - 4 SD and Fd: < - 5 SD. Our data suggest that reduction of CABF should be carefully evaluated for the diagnosis of neurally mediated syncope in pediatric patients. Such a reduction might be an essential mechanism of syncopal attacks.

Outcome of acute lymphoblastic leukemia in children with AL90 regimen: impact of response to treatment and sex difference on prognostic factors

BACKGROUND

In our previous studies, the outcome of high-risk ALL was still poor. In the present study, all children with ALL were classified into three groups and treated with a new regimen (AL90).

PATIENTS AND METHODS

Between 1990 and 1996, 220 children with ALL, treated with the AL90 regimen, were classified into three risk groups: low, intermediate, and high: LR, IR, and HR, respectively. The protocol consisted of three- to five-drug induction, consolidation with intermediate-dose methotrexate and/or cytarabine, mercaptopurine and cyclophosphamide, four-drug intensification, and sequential maintenance therapies. Only intrathecal chemotherapy was used for CNS prophylaxis in the LR group, whereas cranial irradiation was added for the IR and HR groups.

RESULTS

The number of eligible patients was 91: LR group, 71: IR group, and 58: HR group. Complete remission (CR) was obtained in > 98% of the LR and IR groups, while only 88% achieved CR in the HR group. The 5-year event-free survival (EFS) rate was 67.4% in all patients: 70.4% in the LR group, 71.7% in the IR group, and 57.5% in the HR group. With respect to the previous study, EFS in the HR group who showed positive residual leukemia at 14 days was improved, whereas EFS in boys versus girls was significantly lower (48.8% : 85.7%, P = 0.02).

CONCLUSIONS

In high-risk ALL, the rate of induction failure was high and boys had a worse outcome, calling for improvements in induction therapy and a specific approach for boys.

Effects of olprinone, a new phosphodiesterase inhibitor, on gastric intramucosal acidosis and systemic inflammatory responses following hypothermic cardiopulmonary bypass

BACKGROUND

Phosphodiesterase (PDE) III inhibitors have both an inotropic and a peripheral vasodilatory effect, and also inhibit the activation of macrophages. Thus a newly developed PDE III inhibitor, olprinone, could modify gastric intramucosal pH (pHi), systemic oxygen consumption, and systemic inflammatory responses in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB).

METHODS

We studied 23 patients. In 15 patients, olprinone (0.1 or 0.2 microg x kg(-1) x min(-1)) was administered from the commencement of CPB until their admission to the ICU. The other 8 patients received placebo. The pHi and regional CO2 tension (PrCO2) were assessed by a capnometric air tonometry. Systemic inflammatory responses were evaluated by serum interleukin-6 (IL-6), IL-10, and leucocyte counts.

RESULTS

The pHi and PCO2-gap, the difference between PrCO2 and arterial CO2 tension (PaCO2), showed a transient decrease and an increase after CPB, respectively. Although olprinone did not affect pHi, olprinone at 0.2 microg x kg(-1) x min(-1) significantly lessened post-CPB increase in PCO2-gap. Olprinone at 0.2 microg x kg(-1) x min(-1) significantly increased IL-10 and reduced the extent of leucocytosis, while it did not affect IL-6 levels. At the same dosage, olprinone also lessened the surge in systemic oxygen uptake index (VO2) and augmented the increase in mixed oxygen saturation (SvO2) both of which occurred after CPB. At 0.1 microg x kg(-1) x min(-1), however, olprinone did not show any significant effect.

CONCLUSION

Our results suggest that olprinone at 0.2 microg x kg(-1) x min(-1) suppresses gastric intramucosal acidosis and systemic inflammation following CPB.

Long-term outcome of treatment with protocols AL841, AL851, and ALHR88 in children with acute lymphoblastic leukemia: results obtained by the Kyushu-Yamaguchi Children's Cancer Study Group

We analyzed the long-term outcome and late effects of treatment in 187 patients with childhood acute lymphoblastic leukemia (ALL) diagnosed between 1984 and 1990. Overall survival and event-free survival rates were 68.2% +/- 3.7% and 63.2% +/- 3.6% at 15 years, respectively. Of 55 patients who relapsed after achieving the first complete remission (CR), only 17.4% were rescued by salvage therapy. The advantage of stem cell transplantation over chemotherapy was observed only in those patients with bone marrow relapse during therapy. The SD for score height in patients maintaining the first CR significantly decreased at the time of final follow-up compared with that at diagnosis: 0.059 to -0.800 (P < .0001). The decrease was remarkable in patients younger than 5 years at diagnosis. Other late effects included mild liver dysfunction in 18% and hepatitis C virus infection in 9%. Congestive heart failure was observed in only 2.9% of patients despite the high cumulative dose of daunorubicin (450 mg/m2). Although the survival rates of patients on our protocols were comparable to those of other study groups, some modification, including reduction in dose of cranial irradiation and/or anticancer drugs, should be considered to reduce late adverse effects in survivors of childhood ALL.

Effect of low-dose milrinone on gastric intramucosal pH and systemic inflammation after hypothermic cardiopulmonary bypass

OBJECTIVE

To investigate the usefulness of low-dose milrinone on gastric intramucosal pH (pHi) and systemic inflammation in patients undergoing hypothermic cardiopulmonary bypass (CPB).

DESIGN

Prospective randomized study.

SETTING

University hospital.

PARTICIPANTS

Twenty patients scheduled for cardiac surgery.

INTERVENTIONS

Ten patients were administered a low dose of milrinone, 0.25 microg/kg/min, from the initiation of CPB to 1 hour after admission to the intensive care unit. The other patients were administered saline. Supplemental inotropes and intravenous fluid were given to obtain adequate mean arterial blood pressure and pulmonary artery occlusion pressure.

MEASUREMENTS AND RESULTS

Gastric pHi and carbon dioxide pressure (PCO2) were assessed by capnometric air tonometry. The difference between PCO2 and arterial carbon dioxide pressure (PaCO2), PCO2-gap, was also examined. Systemic inflammatory responses were evaluated by serum interleukin-6 and leukocyte counts. Hemodynamics, oxygen delivery index, and oxygen uptake index were monitored with catheters in the radial and pulmonary arteries (thermodilution). The hepatic venous blood flow and left ventricular flow were measured using transesophageal echocardiography. Milrinone prevented gastric intramucosal acidosis, detected as a decrease in pHi or an increase in PCO2-gap, without affecting hepatic venous blood flow. Increases in interleukin-6, leukocyte count, and oxygen uptake index, all of which developed after CPB, were significantly less in the milrinone group than in the control group.

CONCLUSION

These results suggest that in patients undergoing hypothermic CPB, supplemental low-dose milrinone prevents gastric intramucosal acidosis and increases in some markers of systemic inflammation.

Pulmonary lipiodol embolism during transcatheter arterial chemoembolization for hepatoblastoma under general anaesthesia

We present a case of pulmonary embolism that occurred during the injection of lipiodol during transcatheter arterial chemoembolization under general anaesthesia. A 7-year-old child suffering from a large hepatoblastoma was admitted for arterial chemoembolization and carcinostatic administration. Pulmonary embolism due to lipiodol during arterial chemoembolization was evident by a sudden fall in oxyhaemoglobin saturation from 100 to 90%. This was associated with a spread of lipiodol into both lungs, particularly the middle lung zones and detected by chest fluoroscopy. Arterial blood gases returned to normal values 1 day later but pulmonary infiltration persisted for 7 days before final clearance. Pulmonary embolism caused by lipiodol during arterial chemoembolization is infrequent, but such a complication could prove fatal. Understanding the risk of pulmonary embolism in patients receiving lipiodol, during and after arterial chemoembolization, and late onset pulmonary injury is important and a close follow-up for several days after arterial chemoembolization is advisable.

Development of a cancer vaccine: peptides, proteins, and DNA

Genetic changes leading to protooncogene activation qualitatively and/or quantitatively alter their gene products and are exclusively or largely restricted to transforming cells and their precursors. The overexpression of HER2 is among those changes and is often detected in adenocarcinomas such as breast, ovarian, lung, and gastric cancer. This provides a rationale for exploring the possibility that HER2 is a target of host immune responses against cancer cells. We have recently demonstrated that HER2 can be a target for tumor-rejecting immune responses against syngeneic murine HER2+ tumor cells. We defined two different peptides, HER2p63-71 and HER2p780-788, with a Kd anchor motif that can induce CD8+ cytotoxic T lymphocytes (CTLs). The growth of HER2+ syngeneic tumors was suppressed in mice immunized with HER2p63-71 or p780-788. Since murine Kd and human HLA-A24 share a similar anchor motif for peptides, HER2p63 71 and HER2p780-788 were examined for induction of CTLs in HLA-A24+ individuals. CD8+ CTL clones specific for these peptides were established and they lysed HER2+ tumor cells in a human leukocyte antigen (HLA)-A24-restricted manner. To elicit specific CD8+ T cell immune responses against cancer, the development of efficient devices to deliver tumor antigen peptides to the major histocompatibility complex (MHC) class I pathway constitutes a central issue. We have developed a novel formula of hydrophobized polysaccharide nanoparticles which can deliver a HER2 oncoprotein containing an epitope peptide to the MHC class I pathway. We designed a simple protein delivery system: cholesteryl group-bearing polysaccharides, mannan or pullulan (CHM or CHP, respectively), complexed with the truncated HER2 protein containing the 147 N-terminal amino acids. These complexes were able to induce CD8+ CTLs against HER2+ tumors. CTLs were MHC class I restricted and specifically recognized HER2p63-71, a part of a truncated HER2 protein used as an immunogen. The complete rejection of tumors also occurred when CHM-HER2 was applied early after tumor implantation. In the effector phase of in vivo tumor rejection, CD8+ T cells played a major role. The results suggest that this unique hydrophobized polysaccharide may help soluble proteins to induce cellular immunity. Such a novel vaccine may be of potential benefit in cancer prevention and cancer therapy.

Selective uptake by cancer cells of liposomes coated with polysaccharides bearing 1-aminolactose

We investigated the selective uptake of liposomes chemically modified by polysaccharides-cholesterol derivatives with 1-aminolactose (lactose) in two human hepatoma cell lines (HUH7 and Alexander), a human colon cancer cell line (FCC) and a human lung cancer cell line (KNS). The uptakes of the labeled liposomes alone (conventional liposomes), those with cholesterol pullulan (CHP) and with lactose (lactose CHP) were compared in four cancer cells and normal rat hepatocytes after 3 hours of incubation. The radioactivities of the lactose CHP were 4.4, 4, 3.4 and 4.4 times greater than those of CHP in HuH7, Alexander, FCC and KNS cells, respectively, after 3 hours of incubation. All the above differences were statistically significant (p < 0.01). No statistically significant differences were seen in the case of hepatocytes. Thus, cancer cells have a common affinity with lactose CHP liposomes, however, these mechanisms appear to have no connection with the galactose-specific asialoglycoprotein receptors of hepatocytes.

Ganglioside patterns in neuroepithelial tumors of childhood

To elucidate a relationship between neuronal anaplasia, tumor proliferation, and ganglioside contents, we quantified gangliosides by HPTLC in tumors of neuroepithelial tissues at different grade, i. e. peripheral primitive neuroectodermal tumor (PPNET, grade IV), ependymoma (EPEN, grade III), neuroblastoma (NB, grade IV), and dysembryoplastic neuroepithelial tumor (DNT, grade I). PPNET, the most undifferentiated tumor examined had lowest concentration of total lipid-bound sialic acid. GM3 was the major ganglioside in all undifferentiated tumors (46-72.7% of total lipid-bound sialic acid). GD3 was an another component in PPNET and EPEN (7.2-17.3%). Concentration of a complex gangliosides GM1 was decreased in all tumor tissues and those of GT1a, GD1b and GT1b were decreased in tumors of high grade. The results suggest that the composition of gangliosides could be of considerable value in refining the classification of neuroepithelial tumors in infancy and childhood.

Capillary hemangioma of the liver with Kasabach-Merritt syndrome in a neonate: report of a case

Hepatic hemangiomas are benign tumors, and therefore minimally invasive treatment such as irradiation or steroid therapy is often recommended. However, in patients who have a hemangioma complicated by Kasabach-Merritt syndrome, surgical intervention should also be considered because of its confirmative therapeutic effect. We present herein the case of a 32-day-old male infant in whom a huge hepatic hemangioma associated with Kasabach-Merritt syndrome was treated by surgical intervention together with strong antidisseminated intravascular coagulation therapy.

Utility of liposomes coated with polysaccharide bearing 1-amino-lactose as targeting chemotherapy for AH66 hepatoma cells

The cell recognition element is very important for drug delivery systems. We synthesized cholesteryl pullulan (CHP) bearing 1-aminolactose (1-AL) and introduced a saccharide, cholesteryl pullulan bearing 1-aminolactose (1-AL/CHP), to an outer layer of the conventional liposome as a cell recognition element. Lectin recognized the beta-galactose by aggregation of 1-AL/CHP coated liposome (1-AL/CHP liposome). The uptake of this liposome to AH66 rat hepatoma cells was greater than in liposomes without 1-aminolactose in vitro. Furthermore, 1-AL/CHP liposomal adriamycin showed a stronger antitumor effect in comparison with other types of liposomal adriamycin in vitro. When in vivo tumor-targeting efficacy was investigated in AH66 tumor transplanted mice using 3H-liposome, the tumor/serum radioactivity ratio in mice injected with 1-AL/CHP liposome was higher than that of mice injected with other liposomes. These observations suggest that 1-AL is effective as a cell recognition element. As a result, 1-AL/CHP liposome is considered to be a good carrier of anticancer drugs for the active targeting of tumor cells.

Inhibitory effect of TS-962 on the formation of early atherosclerotic lesions in high fat-fed hyperlipidemic hamsters

The hypocholesterolemic and anti-atherosclerotic effect of TS-962, a specific ACAT inhibitor, was investigated in a hamster model fed a high fat diet containing 10% coconut oil and 0.05% cholesterol. Lipid accumulated atherosclerotic lesions were detected by using oil red O staining in the lesion-prone aortic arch. A high dose, estimated to be 15 mg/kg, of TS-962 decreased serum cholesterol to normal levels with reduction of liver cholesterol contents below normal levels, and as a consequence, entirely inhibited the lipid accumulation in the aortic arch. Furthermore, a low dose, estimated to be 1.5 mg/kg, of TS-962 remarkably inhibited aortic lipid accumulation by 73% compared with the control group, without changing either serum cholesterol level or liver cholesterol content. These findings suggest that TS-962 is effective in the primary prevention of atherosclerosis by directly suppressing the formation of foam cells in arteries.

Two-dimensional autoregressive analysis of carotid artery blood flow waveform in children with isolated atrial septal defect

BACKGROUND

The aim of the present study was to analyze the carotid artery blood flow waveform, using a two-dimensional autoregressive modeling approach and component analysis, and to determine the relation between cardiac contractility, peripheral and cerebral circulation and characteristic values of component activities of carotid artery blood flow waveform in patients with atrial septal defect (ASD), with or without congestive heart failure.

METHODS AND RESULTS

We analyzed the carotid artery blood flow waveform of nine patients with ASD and 35 normal controls using a two-dimensional autoregressive modeling approach. The component of impulse response was divided into six groups according to the damping frequency: (i) group I, 0 Hz; (ii) group II, 1-5 Hz; (iii) group III, 5-8 Hz; (iv) group IV, 8-13 Hz; (v) group V, 13-17 Hz and (vi) group VI, > 17 Hz. The decrease of impulse response power-density in patients of groups I, II, III and IV and the prolongation of damping time for patients in groups I and II were particularly noticeable in two ASD patients, whose pulmonary to systemic blood flow ratio was more than 2.7 and whose left ventricular stroke volume was less than 33.1 mL/m2. The power-density of groups I and II varied with cardiac contractility and the power-density of groups III and IV varied with cerebral circulation. In contrast, the damping time of groups I and II changed with the reflection velocity from the position of arterial reflection against blood flow from left ventricle.

CONCLUSIONS

These results may be influenced by the decrease in left ventricular stroke volume and velocity in arterial reflection.

Molecular chaperone-like activity of hydrogel nanoparticles of hydrophobized pullulan: thermal stabilization with refolding of carbonic anhydrase B

We have been studying the formation of hydrogel nanoparticles by the self-aggregation of hydrophobized polysaccharide and the effective complexation between these nanoparticles as a host and various globular soluble proteins as a guest. This paper describes a new finding that refolding of the heat-denatured enzyme effectively occurs with the nanoparticles and beta-cyclodextrin according to a mechanism similar to that of a molecular chaperone. In particular, the irreversible aggregation of carbonic anhydrase B (CAB) upon heating was completely prevented by complexation between the heat-denatured enzyme and hydrogel nanoparticles formed by the self-aggregation of cholesteryl group-bearing pullulan (CHP). The complexed CAB was released by dissociation of the self-aggregate upon the addition of beta-cyclodextrin. The released CAB refolded to the native form, and almost 100% recovery of the activity was achieved. The thermal stability of CAB was drastically improved by capture of the unfolded form which was then released to undergo refolding.

Bone marrow-derived dendritic cells incorporate and process hydrophobized polysaccharide/oncoprotein complex as antigen presenting cells

We have previously shown that a novel hydrophobized polysaccharide/oncoprotein complex vaccine can induce immune responses against the HER2/neu/c-erbB2 (HER2) expressing tumors. Bone marrow-derived dendritic cells (DCs), as antigen presenting cells (APCs), are the first candidates for presentation of tumor antigens. The aim of this study was to see whether DCs are able to elicit antigen specific host immune responses by stimulating the proliferation of T cells after exposure to cholesteryl group bearing pullulan (CHP) and HER2 protein complex. Vaccination by CHP-HER2 complex was as effective as cholesteryl group bearing mannan (CHM) and HER2 complex on which we reported previously. Immunization of mice with HER2 expressing CMS17HE tumor cells generated both CD4+ T cells and CD8+ T cells reactive with CHP-HER2 complex pretreated DCs. In addition, immunization with either CHP-HER2 complex or HER2 protein alone could also generate both CD4+ T cells and CD8+ T cells specifically reactive with CHP-HER2 complex pretreated DCs. The complete rejection of tumors occurred when immunization with CHP-HER2 complex pretreated DCs was started 10 days after tumor inoculation. Therefore, bone marrow-derived DCs pretreated with hydrophobized polysaccharide/oncoprotein complex are a powerful tool for enhancing the effectiveness of oncoprotein for anti-tumor vaccination, opening new options for immune cell therapy.

Self-assembled hydrogel nanoparticle of cholesterol-bearing pullulan as a carrier of protein drugs: complexation and stabilization of insulin

Insulin (Ins) spontaneously and easily complexed with the hydrogel nanoparticle of hydrophobized cholesterol-bearing pullulan (CHP) in water. The complexed nanoparticles (diameter 20-30 nm) thus obtained formed a very stable colloid. The thermal denaturation and subsequent aggregation of Ins were effectively suppressed upon complexation. The complexed Ins was significantly protected from enzymatic degradation. Spontaneous dissociation of Ins from the complex was barely observed, except in the presence of bovine serum albumin. The original physiological activity of complexed Ins was preserved in vivo after i.v. injection.

A novel hydrophobized polysaccharide/oncoprotein complex vaccine induces in vitro and in vivo cellular and humoral immune responses against HER2-expressing murine sarcomas

To elicit specific cellular immune responses against cancer, the development of efficient devices to deliver tumor antigen peptides to the MHC class I pathway constitutes a central issue. We report here a novel formula of hydrophobized polysaccharide nanoparticles, which can deliver a HER2 oncoprotein containing an epitope peptide to the MHC class I pathway. A protein consisting of the 147 amino-terminal amino acids of oncogene erbB-2/neu/HER2 (HER2) was complexed with two kinds of hydrophobized polysaccharides, cholesteryl group-bearing mannan (CHM) and cholesteryl group-bearing pullulan (CHP), to form nanoparticles (CHM-HER2 and CHP-HER2). CHM-HER2 and CHP-HER2 were able to induce CD3+/CD8+ CTLs against HER2-transfected syngeneic fibrosarcoma cell lines. In contrast, the oncoprotein alone failed to do so. These CTLs were Kd-restricted and specifically recognized a peptide (position 63-71) that was a part of a truncated HER2 protein used as an immunogen. In addition, vaccination by CHM-HER2 complexes led to a strongly enhanced production of IgG antibodies against HER2, whereas vaccination with HER2 proteins alone resulted in a production of antibodies at a marginal level. Mice immunized with CHM-HER2 or CHP-HER2 before tumor challenge successfully rejected HER2-transfected tumors. The complete rejection of tumors also occurred when CHM-HER2 was applied not later than 3 days after tumor implantation. In the effector phase of in vivo tumor rejection, CD8+ T cells played a major role. The results suggest that a sort of hydrophobized polysaccharide may help soluble proteins to induce cellular immunity as well enhance humoral immunity; hence, such a novel vaccine may be of potential benefit to cancer prevention and cancer therapy.

[Preliminary screening for antiviral AIDS drugs. VIII. Report for fiscal year 1995]

Preliminary screening of antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 96 samples of different origin tested, two were shown to inhibit the growth of HIV in vitro. One of the positive samples (plant origin) has hopeful signs, as the ranges of effective doses are wider than those of most of positive samples which had been found by us.

Mechanism of beta-adrenergic receptor upregulation induced by ACE inhibition in cultured neonatal rat cardiac myocytes: roles of bradykinin and protein kinase C

BACKGROUND

Although bradykinin is thought to contribute to the effects of ACE inhibitors on the cardiovascular system, its precise role remains to be elucidated. Evidence suggests that bradykinin might be important in the upregulation of beta-adrenergic receptors (beta-ARs) induced by ACE inhibitors, and the role of bradykinin in this effect has now been investigated with cultured neonatal rat cardiac myocytes.

METHODS AND RESULTS

The density of beta-ARs on the myocyte surface was determined with a binding assay with [3H]CGP-12177. Incubation of cultured myocytes for 24 hours with the ACE inhibitor captopril (1 micromol/L) increased beta-AR density by 35% and enhanced the response of cells to isoproterenol but not to forskolin. Neither an angiotensin-II type 1 (AT1) receptor antagonist, CV-11974, nor angiotensin-I affected beta-AR density. However, the bradykinin B2 receptor antagonist Hoe 140 abolished the effect of captopril on beta-AR upregulation in a dose-dependent manner. The protein kinase C inhibitor staurosporine (20 nmol/L) but neither indomethacin nor L-NAME also inhibited captopril-induced upregulation of beta-ARs. Exogenous bradykinin increased the spontaneous beating frequency of cultured myocytes and Hoe 140 abolished this effect. Bradykinin level in the medium increased 1.4-fold by the treatment of cultured myocytes with captopril for 24 hours.

CONCLUSIONS

The results suggest that captopril enhances beta-AR responsiveness by inducing beta-AR upregulation and that the latter effect is mediated by activation of bradykinin B2 receptors and protein kinase C. These observations also offer insight into the different roles of ACE inhibitors and AT1 receptor antagonists in the treatment of heart failure.

Isolated cavernous hemangioma of the stomach in a neonate

This is a report of an extremely rare case of isolated cavernous hemangioma of the stomach found in a neonate. Hematemesis developed in a 7-day-old baby boy weighing 2.8 kg at birth. This was followed by melena. Endoscopic examination findings showed a large hemorrhagic mass on the lesser curvature of the stomach. During laparotomy, a large vascular tumor was identified and subtotal gastrectomy was carried out. On section, the tumor extended through the submucosa to the serosal surface. Histological diagnosis was cavernous hemangioma. The authors could collect only 10 cases of hemangioma of the stomach diagnosed in childhood from the world literature.

[Preliminary screening for antiviral AIDS drugs. VI. Report for fiscal year 1993]

Preliminary screening of antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 138 samples tested, two were found to inhibit the growth of HIV in vitro. Neither of the positive samples has hopeful signs, as the ranges of effective doses of the samples are very narrow.

0/w-emulsion of alpha-linolenic acid stabilized with hydrophobized polysaccharide. Its effect on the growth of human colon cancer cells

To pursue a systemic administration of alpha-linolenic acid (ALA), which is a selective cytotoxic agent, we formulated an ALA o/w-emulsion stabilized by cholesterol-bearing pullulan (CHP-55-2.1) and trioctanoylglyceride (TriC8). This emulsion was stable even in the presence of bovine serum albumin (BSA). Peroxidation of ALA was drastically depressed by the emulsification using CHP. In addition, cytotoxic effect of the CHP/ALA/TriC8-emulsion against human colon cancer cell (RPM14788) was much higher than that of free ALA. However, no significant difference was observed in cell internalization efficiency of ALA between the two. These results suggest that difference in the cytotoxicity between the CHP/ALA/TriC8-emulsion and free ALA may come from difference in the intracellular behavior of ALA.

[Preliminary screening for antiviral AIDS drugs. VII. Report for fiscal year 1994]

Preliminary screening of antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 246 samples of different origin tested, six were shown to inhibit the growth of HIV in vitro. Two of the positive samples have hopeful signs, as the ranges of effective doses are wider than those of most of positive samples which had been found by us.

Partition of polysaccharide-coated liposomes in aqueous two-phase systems

Hydrophobized polysaccharides such as cholesterol-bearing pullulan (CHP), dextran (CHD) and mannan (CHM) effectively coat the liposomal surface. Partition of the hydrophobized polysaccharide-coated liposomes in an aqueous two-phase system (PEO (top)/pullulan (bottom) or PEO (top)/dextran (bottom)) was investigated (PEO = poly(ethylene oxide)). Conventional liposomes without a polysaccharide coat mostly locate at the interface between the two polymer phases. The polysaccharide-coated liposomes, on the other hand, were partly partitioned to the bottom polysaccharide phase depending on the structure of the hydrophobized polysaccharide on the liposomal surface. The affinity between the polysaccharide on the liposomal surface and that in the bulk bottom phase controls the efficiency of partition. The sequence of interaction strength between the two carbohydrates was the following: for the PEO/dextran two-phase system, dextran(liposome)-dextran(bulk) > mannan(liposome)- dextran(bulk) > pullulan(liposome)-dextran(bulk); while for the PEO/pullulan system, the sequence of interaction strength was pullulan(liposome)- pullulan(bulk) > dextran(liposome)-pullulan(bulk) approximately mannan(liposome)-pullulan(bulk).

Interaction between ganglioside-containing liposome and rat T-lymphocyte: confocal fluorescence microscopic study

Interaction between rat T-lymphocytes and a ganglioside (GM3, GD3, GT1b, or GQ1b)-containing liposome was investigated in vitro. The direct stimulation of T cell by a ganglioside-containing liposome was followed by monitoring an increase in the intracellular calcium signal using a confocal laser fluorescence microscopic method. The GT1b- or GQ1b-containing liposome strongly stimulated the cell, while the GM3- or GD3-containing liposome showed much less effect. Free gangliosides did not stimulate the cell at all under the same condition. The extent of the stimulation depended on the surface density of GT1b on the liposome accompanied by a clear threshold concentration. The efficiency of this direct T cell stimulation with the ganglioside-containing liposome was closely related to the efficiency of the tumor growth suppression reported previously by ourselves.

Transfer of membrane proteins from human platelets to liposomal fraction by interaction with liposomes containing an artificial boundary lipid

The direct transfer of membrane proteins from human platelets to the liposomal fraction was examined, particularly in relation to platelet activation during the process. The incorporation of an artificial boundary lipid, 1,2-dimyristoylamido-1,2-deoxyphosphatidylcholine (DDPC), in the interacting liposome considerably enhanced the efficiency of the protein transfer. The transfer proceeded with neither significant activation nor lysis of the platelet, and the activation of the platelet with thrombin did not affect the amount of the transferred proteins. A wide range of platelet membrane proteins was transferred, and they were almost comparable to those in a sample prepared by glycerol lysis/centrifugation. In addition, they included the major surface glycoproteins GPIIb and GPIIIa without noticeable contamination of soluble cytosol proteins. The protein transfer method is a one-pot process and clearly more convenient than the conventional 'extract and reconstitute' approach. These results strongly support the use of the transfer process, especially with DDPC, as an alternative to the conventional detergent-solubilization or the solvent-extraction methods for preparation of samples of platelet membrane proteins.