Relationship between office blood pressure and actual antihypertensive drug use in patients with hypertension following the promulgation of the guidelines for hypertension (JSH2019)

To achieve appropriate blood pressure control in the treatment of hypertension in Japan, this study examined the relationship between office blood pressure and actual antihypertensive drug use in general hospitals following the promulgation of the guidelines for hypertension (JSH2019). This study focused on blood pressure levels and drug use in outpatients on antihypertensive treatment from June to July 2020. The subjects were 2,537 patients classified into four groups based on their medical history, patients with: hypertension only; hypertension and cardiovascular disease; hypertension and dyslipidaemia; and hypertension and diabetes mellitus. The results showed a significant difference in systolic blood pressure (SBP) between patients with hypertension only and those with hypertension and cardiovascular disease (138.3±17.9 mmHg vs 135.6±19.9 mmHg, p<0.05). Regarding actual drug use, it was found that diuretics were prescribed more frequently in patients with hypertension and cardiovascular disease than in those with hypertension alone (15.5% vs 37.9%, p<0.05), even though the number of drugs for hypertension did not differ significantly. In addition, the dose of diuretics was greater only in patients with cardiovascular disease. These results show the actual drug use and blood pressure for each comorbidity. Furthermore, they suggest that the results of antihypertensive treatment may differ by changing the combination and dosage of antihypertensive drugs without changing the number of antihypertensive drugs used. The study also shows the problem of using less diuretics depending on the risk the patient has, and solving the problem may lead to achieving further antihypertensive goals.

Evaluating the impact of de-escalating antimicrobial therapy in burn patients: a retrospective cohort study

Antimicrobials should be used appropriately to minimise the risk of resistant strains arising in association with overuse. De-escalation of antimicrobial therapy is one strategy used to ensure appropriate use, but its safety and efficacy in burn patients are unclear. The aim of this study was to evaluate the safety and efficacy of de-escalation therapy for treating infections in burn patients. This retrospective cohort study investigated patients admitted to our intensive care unit with burns and treated for infection between October 1, 2013, and September 30, 2020. Patients were classified into a de-escalation group (Group D) comprising patients treated with empiric antimicrobial therapy followed by de-escalation and a non-de-escalation group (Group ND) comprising patients who did not undergo de-escalation. Characteristics and outcomes were compared between groups. Forty-three patients met the inclusion criteria, including 15 patients in Group D and 28 patients in Group ND. Bacterial species commonly detected in these patients were Corynebacterium spp. (17.3%), Pseudomonas aeruginosa (16.1%), and Staphylococcus aureus (9.6%) . No inter-group difference was seen in 28-day mortality (6.7% vs 21.4%, p =0.391). Multidrug-resistant strains were detected significantly less frequently in Group D (13.0%) than in Group ND (26.1%, p =0.003). De-escalation was associated with use of two or more antimicrobials as empiric antimicrobial therapy. As the use of de-escalation in infection treatment did not impact 28-day mortality, de-escalation might be safe for treating infections in burn patients.

Preparation and evaluation of orally disintegrating tablets containing taste masked microparticles of acetaminophen

In the present work, taste masked particles of acetaminophen (AAP), a highly soluble bitter tasting drug, were developed and ODT containing the taste masked particles were prepared. Taste masked particles of AAP were prepared using different amounts of tetraglycerol polyricinoleate (TGPR) and Eudragit ®E100. Although the drug content ratio and drug recovery decreased with increasing TGPR, drug release from AAP-CR100 particles containing a large amount of TGPR was mostly suppressed for 2 min. Hence, AAP-CR100 was incorporated into ODT as taste masked particles for AAP. Three major disintegrants were used for ODT, and it was confirmed that the tensile strength of all formulations showed applicable hardness for handling. The AAP-CR100-CP(40) formulation containing crospovidone showed the shortest disintegration time and the drug release from AAP-CR100-CP(40) into pH 6.8 test solution was suppressed compared with commercial AAP tablets. Because the drug release from AAP-CR100-CP(40) into the pH 1.2 test solution was rapid, it was suggested that drug release from AAP-CR100-CP(40) is suppressed in the oral cavity, and the drug is released promptly in the stomach. Thus AAP-CR100-CP(40) may be useful as an ODT in which the dissolution of AAP in the oral cavity is suppressed.

Remarkable Improvement of Cardiac Function After Pre-emptive Kidney Transplant in a Patient With Severe Mitral Regurgitation Accompanied by Low Cardiac Function: A Case Report

Patients with end-stage renal disease are at a high risk for cardiovascular diseases. It is controversial whether end-stage renal disease patients with low cardiac function can safely accept kidney transplant. Here, we present a 42-year-old kidney transplant recipient with severe mitral regurgitation accompanied by low cardiac function. He wanted to undergo a pre-emptive kidney transplant from his uncle. We decided to perform living kidney transplant prior to cardiac surgery. Despite adequate ultrafiltration and hemodiafiltration before operation, the patient's ejection fraction still remained 35% 1 day before transplant. He showed complete recovery of cardiac function in only 2 days after pre-emptive kidney transplant, although his body weight did not change before and after the operation. Early removal of the uremic toxin or inflammatory cytokines may play a role in rapid improvement of the cardiac function. Increase of vasoactive substances by improvement of kidney function may lead to reduction of afterload and amelioration of cardiac microcirculation. This report also suggests that optimal timing for operation might be important.

Systemic administration of α-lipoic acid suppresses excitability of nociceptive wide-dynamic range neurons in rat spinal trigeminal nucleus caudalis

Although a modulatory role has been reported for α-lipoic acid (LA) on T-type Ca²⁺ channels in the nervous system, the acute effects of LA in vivo, particularly on nociceptive transmission in the trigeminal system, remain to be determined. The aim of the present study was to investigate whether acute intravenous LA administration to rats attenuates the excitability of wide dynamic range (WDR) spinal trigeminal nucleus caudalis (SpVc) neurons in response to nociceptive and non-nociceptive mechanical stimulation in vivo. Extracellular single unit recordings were made from seventeen SpVc neurons in response to orofacial mechanical stimulation of pentobarbital-anesthetized rats. Responses to both non-noxious and noxious mechanical stimuli were analyzed in the present study. The mean firing frequency of SpVc WDR neurons in response to both non-noxious and noxious mechanical stimuli was significantly and dose-dependently inhibited by LA (1-100 mM, i.v.) and maximum inhibition of the discharge frequency of both non-noxious and noxious mechanical stimuli was seen within 5 min. These inhibitory effects lasted for approximately 10 min. These results suggest that acute intravenous LA administration suppresses trigeminal sensory transmission, including nociception, via possibly blocking T-type Ca²⁺ channels. LA may be used as a therapeutic agent for the treatment of trigeminal nociceptive pain.

FOXO3 is essential for CD44 expression in pancreatic cancer cells

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal types of cancer and the 5-year survival rate is only 5%. Several studies have suggested that cancer stem cells (CSCs) are thought to be involved in recurrence and metastasis and so it is essential to establish an approach targeting CSCs. Here we have demonstrated that cyclic guanosine monophosphate (cGMP) suppressed CD44 expression and the properties of CSCs in PDAC. Microarray analysis suggested that cGMP inhibited Forkhead box O3 (FOXO3), which is known as a tumor suppressor. Surprisingly, our data demonstrated that FOXO3 is essential for CD44 expression and the properties of CSCs. Our data also indicated that patients with high FOXO3 activation signatures had poor prognoses. This evidence suggested that cGMP induction and FOXO3 inhibition could be ideal candidates for pancreatic CSC.

Usefulness of intraoperative diagnosis of hepatic tumors located at the liver surface and hepatic segmental visualization using indocyanine green-photodynamic eye imaging

BACKGROUND

To improve the diagnostic accuracy for hepatic tumors on the liver surface, we investigated the usefulness of an indocyanine green-photodynamic eye (ICG-PDE) system by comparison with Sonazoid intraoperative ultrasonography (IOUS) in 117 patients. Hepatic segmentation by ICG-PDE was also evaluated.

METHODS

ICG was administered preoperatively for functional testing and images of the tumor were observed during hepatectomy using a PDE camera. ICG was injected into portal veins to determine hepatic segmentation.

RESULTS

Accurate diagnosis of liver tumors was achieved with ICG-PDE in 75% of patients, lower than with IOUS (94%). False-positive and false-negative diagnosis rates for ICG-PDE were 24% and 9%, respectively. New small HCCs were detected in 3 patients. The ICG fluorescent pattern in tumors was strong staining in 41%, weak staining in 13%, rim staining in 20% and no staining in 26%. Hepatocellular carcinoma predominantly showed strong staining (61%), while rim staining predominated in cholangiocellular carcinoma (60%) and liver metastasis (55%). Hepatic segmental staining was performed in 28 patients, proving successful in 89%.

CONCLUSION

ICG-PDE is a useful tool for detecting the precise tumor location at the liver surface, identifying new small tumors, and determining liver segmentation for liver resection.

Influence of losartan intake on the circadian rhythm of melatonin secretion in humans

It has been reported that losartan, an angiotensin II receptor blocker, alters the circadian rhythm of melatonin secretion and significantly reduces melatonin production. However, this finding has been confirmed at the animal experiment level only, and there are no reports of studies in humans. Therefore, we performed this study to confirm the reproducibility of the aforementioned findings of animal experiments in humans. Ten male subjects who were in good general health and free from any medical condition were recruited for this study. After a preliminary observation period of 7 days, the subjects received oral losartan treatment, 50 mg daily for 7 days. Blood samplings for measurement of the plasma melatonin concentrations were performed on day 7 of the preliminary observation period and day 7 of the losartan treatment period. The circadian rhythm of melatonin secretion after the 7-day treatment with losartan showed no significant difference from that recorded before the losartan administration. The significant decrease of the home blood pressure was observed on the afternoons. The blood samples showed significant decrease of the serum sodium and uric acid levels, along with a significant increase of the serum potassium level. The pharmacological actions of losartan at the ordinarily used clinical dose level were confirmed in humans, however, no significant inhibitory effect of the drug on melatonin secretion could be confirmed. These results are expected to be useful for guiding the proper use of angiotensin II receptor blockers.

Examination of factors that delay the elution of acetaminophen from over-the-counter drugs

The information on the stability of medications is important to secure their quality. There is, however, little information about the stability of medications which assume to be kept by patients and customers. We previously showed that a delay in drug release occurs in some over-the-counter (OTC) drugs following storage in a high temperature, high humidity environment. In this study we prepared model tablet formulations containing an active ingredient and excipients to investigate the cause of this delayed release. The results reveal that delayed release occurs in preparations compounded with acetaminophen (AA) as the active ingredient and erythritol (ET) and crospovidone (CP) as excipients. In addition, ET deliquesces in a high humidity environment, then incorporates other particles during room temperature storage to form an aggregate. SEM observations and micropore distribution measurements conducted on OTC tablets that exhibit delayed release revealed that the number of intraparticle pores decreased after storage under high temperature, high humidity conditions. Thus, the delayed release by these pharmaceutical product formulations may be due to a change in the micropore structure both on the surface and within the particles, thereby decreasing the solvent infiltration pathways leading to the interior of the preparation.

Prevalence of depression and depressive symptoms among older Japanese people: comorbidity of mild cognitive impairment and depression

BACKGROUND

The aim of the study was to estimate the prevalence of DSM-III-R major depressive episodes (MDEs), depressive symptoms cases (DSCs) (defined as a score of ≥6 on the Geriatric Depression Scale but falling short of MDE), and coexisting mild cognitive impairment (MCI) among Japanese community-dwelling older people.

METHODS

Prevalence was estimated based on screening evaluation, individual interviews, and door-to-door visits. MDE and DSC were diagnosed, and the cognitive status of the participants was determined to be dementia, MCI, or normal.

RESULTS

A total of 1888 subjects of 2698 candidates (70.0%) participated. The prevalence of MDE and DSC were estimated to be 4.5% (95% CI, 3.4-6.0) and 11.5% (95% CI, 4.2-28.0), respectively. MCI was more prevalent in subjects with depression (26.2%) than those with normal mood (17.9%). Although no prototypical profile of cognitive dysfunction was revealed, multiple MCI was more prevalent in subjects with depression (12.2%) than subjects with normal mood (3.8%). Conversely, subjects with MCI (26.3%) were more likely to develop depression compared with those with normal cognitive function (18.0%).

CONCLUSIONS

The prevalence of depression in our subjects seems to be similar with that of previous studies. MCI was more prevalent in subjects with depression than those with normal mood. Individuals with depression showed no particular association with any of the four MCIs. Given that depression and MCI are often associated with each other and that MCI is a predictor for development of dementia, the risk of developing dementia in the depressed older people with coexisting MCI should be acknowledged.

Role of major histocompatibility complex class II in the development of autoimmune type 1 diabetes and thyroiditis in rats

Although the MHC class II 'u' haplotype is strongly associated with type 1 diabetes (T1D) in rats, the role of MHC class II in the development of tissue-specific autoimmune diseases including T1D and autoimmune thyroiditis remains unclear. To clarify this, we produced a congenic strain carrying MHC class II 'a' and 'u' haplotypes on the Komeda diabetes-prone (KDP) genetic background. The u/u homozygous animals developed T1D similar to the original KDP rat; a/u heterozygous animals did develop T1D but with delayed onset and low frequency. In contrast, none of the a/a homozygous animals developed T1D; about half of the animals with a/u heterozygous or a/a homozygous genotypes showed autoimmune thyroiditis. To investigate the role of genetic background in the development of thyroiditis, we also produced a congenic strain carrying Cblb mutation of the KDP rat on the PVG.R23 genetic background (MHC class II 'a' haplotype). The congenic rats with homozygous Cblb mutation showed autoimmune thyroiditis without T1D and slight to severe alopecia, a clinical symptom of hypothyroidism such as Hashimoto's thyroiditis. These data indicate that MHC class II is involved in the tissue-specific development of autoimmune diseases, including T1D and thyroiditis.

Effects of kaempferol on the mechanisms of drug resistance in the human glioblastoma cell line T98G

Food contains components that may either increase or decrease the bioavailability of a drug. In particular, it is known that grapefruit juice and St. John's Wort induce drug interactions via an effect on the drug-metabolizing enzyme cytochrome P450 (CYP). However, interactions with membrane transporters, such as P-glycoprotein and multidrug resistance-related protein (MRP), may also influence drug bioavailability. The objective of the present study was to investigate the effects of kaempferol, a flavonoid present in food, on the cytotoxicity of anticancer drugs and the mechanisms of drug resistance in the human glioblastoma cell line T98G. Acute exposure to kaempferol inhibited the efflux of calcein, a substrate of MRP; however, chronic exposure caused no apparent effect on calcein efflux. The cytotoxicity of doxorubicin was not influenced by chronic exposure of cells to kaempferol, although that of cisplatin was significantly reduced. Multidrug resistance is often associated with increased levels of MRP1, glutathione S-transferase (GST) and activity by chronic exposure to kaempferol, although MRP2 protein levels are decreased. Accordingly, we hypothesized that the cytotoxicity of anticancer drugs that conjugate with glutathione and the substrate of MRPs may be influenced by long-term intake of drugs such as kaempferol, which are substrates of MRPs and GST.

Prevalence of four subtypes of mild cognitive impairment and APOE in a Japanese community

BACKGROUND

The results of previous reports estimating the prevalence of mild cognitive impairment (MCI) have varied widely according to the criteria used to define MCI.

METHODS

We assessed the cognitive function of Japanese community-dwelling individuals >or=65 years old and attempted to estimate the prevalence of four MCI subtypes (amnestic single, amnestic multiple, nonamnestic single, and nonamnestic multiple) using two cutoffs (1 and 1.5 SD) below normative standard. Presence of apolipoprotein E4 allele (APOE4), which is known as a strong risk factor for AD, is reportedly associated with high risk of conversion from MCI to AD. We therefore calculated the frequency of APOE4 carriers for each MCI subtype.

RESULTS

Initially 1888 (70%) of 2698 baseline samples participated, and 1433 (53%) subjects who had complete clinical data including APOE typing remained for the final analysis. The prevalence of MCI subtypes varied within the range of 1.7-16.6%, depending on the criteria applied. Prevalence of MCI was higher using a cutoff at -1.0 SD than at -1.5 SD, and prevalence of amnestic MCI single at -1.5 SD was lowest among all subtypes of MCI. Frequency of APOE4 was higher for amnestic MCI than for non-amnestic MCI or the cognitively normal group.

CONCLUSION

The prevalence of MCI was highly dependent on the diagnostic criteria applied. A higher frequency of APOE4 in participants with amnestic MCI subtype suggested a greater risk of future AD. For future interventions to delay the onset of dementia, targeting individuals with amnestic MCI multiple at -1 SD might be desirable.

Neutrophil elastase inhibitor (sivelestat) reduces the levels of inflammatory mediators by inhibiting NF-kB

OBJECTIVE

Sivelestat sodium hydrate (sivelestat) is a specific synthetic inhibitor of neutrophil elastase (NE). Various studies suggest that sivelestat treatment reduces inflammation. In this study, we tested the hypothesis that sivelestat acts as an inhibitor of inflammatory mediators and prevents nuclear factor-kB (NF-kB) activation.

METHODS

In the presence and absence of sivelestat, the mouse macrophage cell line RAW 264.7 was stimulated with lipopolysaccharide (LPS) and the levels of inflammatory mediators (TNF-alpha, IL-6 and high mobility group box 1 (HMGB1)) and nitrite in the cell supernatant were measured, along with inducible nitric oxide synthase (iNOS) expression.

RESULTS

While LPS administration increased the secretion of inflammatory mediators and nitric oxide (NO), sivelestat decreased the secretion of these mediators. Cell signaling studies demonstrated that sivelestat decreased NF-kB activation by inhibiting IkB phosphorylation.

CONCLUSION

Sivelestat may inhibit the various inflammatory mediators through NF-kB inhibition.

Relationship between period of survival and clinicopathological characteristics in patients with colorectal liver metastasis

AIM

Cancer death in the early period after hepatectomy still occurs in patients with colorectal liver metastasis (CLM). We examined the relationship between clinicopathological parameters and survival periods in 130 CLM patients who underwent hepatectomy.

PATIENTS/METHODS

Patients were divided into four groups: Group 1 (5-year survivors without tumor relapse), Group 2 (survivors at 2-5 years), Group 3 (cancer death at 2-5 years), and Group 4 (cancer death within 2 years).

RESULTS

A short surgical margin was frequent in Group 4 compared to Group 1 (31 vs. 78%, P<0.05). Primary node-positive status, absence of fibrous pseudo-capsular formation, higher Clinical Risk Score, and tumor recurrence within 12 months were frequent in Group 4 (P<0.05). Multivariate analysis revealed a short surgical margin (HR; 3.5) and early tumor relapse (HR; 5.9) as independently significant related parameters (P<0.05).

CONCLUSIONS

Sufficient surgical margins and careful follow-up for early tumor relapse may be important for improving postoperative outcomes for CLM patients.

Dementia and mild cognitive impairment among non-responders to a community survey

We aimed to estimate the prevalence of mild cognitive impairment (MCI) among elderly non-responders to a community-based survey. We conducted a two-phase, population-based cross-sectional study of community-dwelling individuals aged 65 years or older in Tone, located in central Japan. The first phase of the study consisted of physical and cognitive examinations of individuals who responded to the first recruitment (quick-responders), whereas the second phase included individuals who did not respond in the first phase (delayed-responders). We compared the prevalence of MCI and dementia between delayed-responders and quick-responders. Of the 2,698 potential candidates, 1,888 (1,619 quick-responders, 225 delayed-responders, and 44 nursing home residents) were enrolled (70.0%). The prevalence of MCI was 2.3-fold increased in delayed-responders compared to the quick-responders (OR=2.27, 95% CI: 1.37-3.77, p=0.002, aged< or =74). In order to develop a method for the early detection of dementia, we must pay more attention to delayed-or non-responders.

Comparison of survival between anatomic and non-anatomic liver resection in patients with hepatocellular carcinoma: significance of surgical margin in non-anatomic resection

AIMS

Anatomic resection, i.e., systematic removal of a liver segment confined by portal branches, is theoretically effective in eradicating intrahepatic metastasis of hepatocellular carcinoma (HCC). The procedure may reduce tumour recurrence and enhance survival of HCC patients. To determine the significance of anatomic resection for HCC patients, we retrospectively conducted a comparative analysis between anatomic (AR) and non-anatomic liver resection (NAR) in 113 Japanese HCC patients with a solitary tumour, a tumour located within one segment, absence or invasion of distal to second order branches of the portal vein, and absence or invasion of peripheral branches of the hepatic vein.

METHODS

Patients were divided into two groups, AR group (n = 49) and NAR group (n = 64).

RESULTS

The prevalence of liver damage Grade B in the NAR group was significantly greater than in the AR group (p < 0.05). Tumour-free and overall survival following liver resection was not significantly different between AR and NAR groups. In the NAR group, tumour-free and overall survival in patients with tumour exposure at the surgical margin was significantly lower than with a surgical margin greater than 0 mm (not exposed) (p < 0.05). Survival between the AR and NAR groups without tumour exposure at the surgical margin was similar.

CONCLUSIONS

Anatomic resection is the theoretical aim. In HCC patients with impaired liver functions, limited liver resection without tumour exposure may provide longer tumour-free and overall survival.

Trisectionectomy for large hepatocellular carcinoma using the liver hanging maneuver

BACKGROUND/PURPOSE

Large liver tumors often expand and severely compress intrahepatic vessels. In cases of the trisectionectomy for such tumors, however, it is difficult to adequately expose the transection planes. The liver hanging maneuver (LHM) is a useful technique for hemihepatectomy and an adequate transection plane might be also required in trisectionectomy.

METHODS

LHM procedure is basically followed by the Belghiti's method. A nasogastric tube was used for hanging. At the hepatic hilum, the tube was placed between the liver and Glisson's pedicle.

RESULTS

We report here the application of LHM for right and left trisectionectomy in patients with a large hepatoma in two cases. In case of a right trisectionectomy for a large tumor compressing the umbilical Glisson's pedicle, an adequate transection plane was obtained using the LHM because the resected and remnant livers rotated to the other side upon lifting the tube during transection. In case of a left trisectionectomy for a large hepatic tumor compressing the right hepatic vein, an adequate transection plane along the right hepatic vein was obtained using LHM as well.

CONCLUSIONS

LHM is a useful surgical application for right and left trisectionectomy in patients with large liver tumors compressing the cut plane.

Genetic parameters for image analysis traits on M. longissimus thoracis and M. trapezius of carcass cross section in Japanese Black steers

In Japan, the degree of marbling in ribeye (M. longissimus thoracis) is evaluated in the beef meat grading process. However, other muscles (e.g., M. trapezius) are also important in determining the meat quality and carcass market prices. The purpose of this study was to estimate genetic parameters for M. longissimus thoracis (M-LONG) and M. trapezius (M-TRAP) of carcass cross section of Japanese Black steers by computer image analysis. The number of records of Japanese Black steers and the number of pedigree records were 2,925 and 10,889, respectively. Digital images of the carcass cross section were taken between the sixth and seventh ribs by photographing equipment. Muscle area (MA), fat area ratio (FAR), overall coarseness of marbling particles (OCM), and coarseness of maximum marbling particle (MMC) in M-LONG and M-TRAP were calculated by image analysis. Genetic parameters for these traits were estimated using the AIREMLF90 program with an animal model. Fixed effects that were included in the model were dates of arrival at the carcass market and slaughter age (mo), and random effects of fattening farms, additive genetic effects and residuals were included in the model. For M-LONG, heritability estimates (+/-SE) were 0.46 +/- 0.06, 0.59 +/- 0.06, 0.47 +/- 0.06, and 0.20 +/- 0.05 for MA, FAR, OCM, and MMC, respectively. Heritability estimates (+/-SE) in M-TRAP were 0.47 +/- 0.06, 0.57 +/- 0.07, 0.49 +/- 0.07, and 0.13 +/- 0.04 for the same traits. Genetic correlations between subcutaneous fat thickness and FAR for M-LONG and M-TRAP were negative (-0.21 and -0.19, respectively). Those correlations between M-LONG and M-TRAP were moderate to high for MA, FAR, OCM, and MMC (0.38, 0.52, 0.39, and 0.60, respectively). These results indicate that other muscles including M-LONG should be evaluated for more efficient genetic improvement.

An in vitro study of the effect of some dietary components on calculus formation: regulation of calcium phosphate precipitation

OBJECTIVE

We studied the effects of food components on the in vitro formation of calcium phosphate precipitates.

MATERIALS AND METHODS

The effects of food components, such as starch, soybean flour, fish meal, rapeseed oil, and coconut oil, on calcium phosphate precipitation were studied using a pH drop method.

RESULTS

Although the addition of starch had no effect on the rate of precipitation of amorphous calcium phosphate (ACP), it increased both the rate of transformation of ACP to hydroxyapatite (HAP) and the induction time (i.e. time for the initiation of transformation of ACP to HAP to occur); this was irrespective of the heat treatment of the starch. Amylopectin (insoluble constituent of starch) was effective in increasing the rate of HAP transformation, but amylose (soluble constituent of starch) was not. Oil specimen obtained from rapeseed (400 microl ml(-1)) increased the entire reaction of calcium phosphate precipitation, but that from coconut did not. Protein food, such as soybean flour and fish meal, decreased the rate of transformation of ACP to HAP and increased the induction time, while they had no effect on the rate of ACP precipitation.

CONCLUSION

These results suggest that carbohydrate and oil (both are staple diets for the humans) enhance oral calcification (dental calculus formation or re-mineralization of tooth enamel), while side dishes of protein food would decrease it.

An ionic polymer bead-supported lipid system

In this paper, we report on the preparation of an ionic polymer bead-supported lipid system several hundred micrometers in diameter. The electrostatic attractive interactions between anionic lipids and cationic polymer beads served as a "molecular glue" to immobilize the lipids on the beads, and then the immobilized lipids prompted the spontaneous formation of lipid bilayer membranes. Confocal fluorescence microscopic techniques revealed that the lipid bilayer membranes were located along the outline of the beads. In addition, the integrity of the lipid bilayer membranes was microscopically confirmed by a low-molecular-weight dye (trypan blue) exclusion test.

Nucleus accumbens nitric oxide immunoreactive interneurons receive nitric oxide and ventral subicular afferents in rats

The nitric oxide generating neurons of the nucleus accumbens exert a powerful influence over striatal function, in addition, these nitrergic inputs are in a position to regulate the dopaminergic and glutamatergic inputs on striatal projection neurons. It was the aim of this study to establish the source of the glutamatergic drive to nitric oxide synthase interneurons of the nucleus accumbens. The nucleus accumbens nitric oxide-generating neurons receive asymmetrical, excitatory, presumably glutamatergic inputs. Possible sources of these inputs could be the limbic and cortical regions known to project to this area. To identify sources of the excitatory inputs to the nitric oxide synthase-containing interneurons of the nucleus accumbens in the rat we first examined the ultrastructural morphology of asymmetrical synaptic specializations contacting nitric oxide synthase-immunohistochemically labeled interneurons in the nucleus accumbens. Neurons were selected from different regions of the nucleus accumbens, drawn using camera lucida, processed for electron microscopic analysis, and the boutons contacting nitric oxide synthase-labeled dendrites were photographed and correlated to the drawings. Using vesicle size as the criterion the source was predicted to be either the prefrontal cortex or the ventral subiculum of the hippocampus. To examine this prediction, a further study used anterograde tracing from both the prefrontal cortex and the ventral subiculum, and nitric oxide synthase immunohistochemistry with correlated light and electron microscopy. Based on appositions by anterogradely labeled fibers, selected nitric oxide synthase-labeled neurons within the nucleus accumbens, were examined with electron microscopic analysis. With this technique we confirmed the prediction that subicular afferent boutons make synaptic contact with nitric oxide synthase interneurons, and demonstrated anatomically that nitric oxide synthase boutons make synaptic contact with the dendritic arbors of nitric oxide synthase interneurons. We suggest that the subicular input may excite the nitric oxide synthase neurons synaptically, while the nitric oxide synthase-nitric oxide synthase interactions underlie a nitric oxide signaling network which propagates hippocampal information, and expands the hippocampus's influence on 'gating' information flow across the nucleus accumbens.

Changes in hippocampal GABABR1 subunit expression in Alzheimer's patients: association with Braak staging

Alterations in the gamma-aminobutyric acid (GABA) neurotransmitter and receptor systems may contribute to vulnerability of hippocampal pyramidal neurons in Alzheimer's disease (AD). The present study examined the immunohistochemical localization and distribution of GABA(B) receptor R1 protein (GBR1) in the hippocampus of 16 aged subjects with a range of neurofibrillary tangle (NFT) pathology as defined by Braak staging (I-VI). GBR1 immunoreactivity (IR) was localized to the soma and processes of hippocampal pyramidal cells and some non-pyramidal interneurons. In control subjects (Braak I/II), the intensity of neuronal GBR1 immunostaining differed among hippocampal fields, being most prominent in the CA4 and CA3/2 fields, moderate in the CA1 field, and very light in the dentate gyrus. AD cases with moderate NFT pathology (Braak III/IV) were characterized by increased GBR1-IR, particularly in the CA4 and CA3/2 fields. In the CA1 field of the majority of AD cases, the numbers of GBR1-IR neurons were significantly reduced, despite the presence of Nissl-labeled neurons in this region. These data indicate that GBR1 expression changes with the progression of NFT in AD hippocampus. At the onset of hippocampal pathology, increased or stable expression of GBR1 could contribute to neuronal resistance to the disease process. Advanced hippocampal pathology appears to be associated with decreased neuronal GBR1 staining in the CA1 region, which precedes neuronal cell death. Thus, changes in hippocampal GBR1 may reflect alterations in the balance between excitatory and inhibitory neurotransmitter systems, which likely contributes to dysfunction of hippocampal circuitry in AD.