Analysis of dispersion and aggregation behavior of carbon black particles in aqueous suspension by colloid probe AFM method

To clarify the role of polymer dispersants at the carbon black (CB) nanoparticle/liquid interface, the adsorbed structure of the dispersants and the interactions between particle surfaces was evaluated using colloid probe AFM. As it is difficult to prepare stable spherical granules consisting of CB nanoparticles with diameters on the scale of several microns, for a colloidal probe by spray drying and sintering, CB nanoparticles were uniformly coated on the surface of spherical resin particles using a physical composing process. In order to establish the mechanism of action of the CB polymer dispersant by using the prepared colloid probe, polyethyleneimine (PEI) and PEI functionalized with a hydrophobic toluoyl group (T-PEI) were compared. It was found that on the adsorption of T-PEI, the viscosity of the aqueous CB suspension and the size of the aggregates were remarkably decreased in acidic conditions. Although the amounts of PEI and T-PEI adsorbed onto the CB were almost the same, a larger repulsive interaction was observed in the case of the T-PEI. CB nanoparticle dispersion was promoted by the increase in steric repulsion due to the structure of the adsorbed T-PEI.     

Short communication: Serum osteoprotegerin concentrations in periparturient dairy cows

Dairy cows experience hypocalcemia at the onset of lactation; however, the contribution of bone metabolism to circulating Ca concentrations during the periparturient period is not well understood. Osteoprotegerin (OPG) protects against loss of skeletal mass by regulating osteoclastogenesis. We previously reported that the bone resorption increased around parturition in dairy cows from the perspective of bone markers in blood. The aim of this study was to explore osteoclastic bone resorption in periparturient dairy cows by measuring changes in serum OPG concentrations around calving. The OPG concentrations were evaluated in primiparous (n = 9) and multiparous (n = 9) cows at 21 d precalving and over 5 d after calving. Based on mixed model analyses, the multiparous cows had a higher serum OPG concentration than primiparous cows at precalving and exhibited a significant decline in serum OPG and Ca concentrations after calving. In contrast to multiparous cows, primiparous cows did not exhibit these changes. Therefore, we hypothesized that multiparous cows preserve their bone mineral content during late pregnancy and activate the osteoclastic bone resorption after calving. Based on our serum OPG data, we identified the different periparturient osteoclastic bone resorption patterns in healthy primiparous and multiparous dairy cows.     

Complete deficiency of glycophorin A in red blood cells from mice with targeted inactivation of the band 3 (AE1) gene

Glycophorin A is the major transmembrane sialoglycoprotein of red blood cells. It has been shown to contribute to the expression of the MN and Wright blood group antigens, to act as a receptor for the malaria parasite Plasmodium falciparum and Sendai virus, and along with the anion transporter, band 3, may contribute to the mechanical properties of the red blood cell membrane. Several lines of evidence suggest a close interaction between glycophorin A and band 3 during their biosynthesis. Recently, we have generated mice where the band 3 expression was completely eliminated by selective inactivation of the AE1 anion exchanger gene, thus allowing us to study the effect of band 3 on the expression of red blood cell membrane proteins. In this report, we show that the band 3 -/- red blood cells contain protein 4.1, adducin, dematin, p55, and glycophorin C. In contrast, the band 3 -/- red blood cells are completely devoid of glycophorin A (GPA), as assessed by Western blot and immunocytochemistry techniques, whereas the polymerase chain reaction (PCR) confirmed the presence of GPA mRNA. Pulse-label and pulse-chase experiments show that GPA is not incorporated in the membrane and is rapidly degraded in the cytoplasm. Based on these findings and other published evidence, we propose that band 3 plays a chaperone-like role, which is necessary for the recruitment of GPA to the red blood cell plasma membrane.     

HYDROGEN PULVERIZATION OF Nb_3Al AND NbCr_2 ALLOYS

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Acute myocardial infarction in a patient during dobutamine stress echocardiography

Combined chemotherapy/radiotherapy treatments appear to yield better results in locally advanced non-small-cell lung cancer (NSCLC) than radiotherapy alone. The optimal induction chemotherapy regimen remains to be established. In the present study, chemotherapy with cisplatin and vinorelbine was used prior to radical radiotherapy in Stage III-B NSCLC. Thirty-three patients were entered prospectively into a Phase II study. Treatment consisted of three cycles of chemotherapy with cisplatin 100 mg/m2 on day 1 and vinorelbine 30 mg/m2 on days 1 and 8, followed by thoracic radiotherapy (60 Gy). Twenty-two percent of the 33 patients had grade 3-4 leukopenia, and there were six episodes (in 4 patients) of neutropenia-associated fever. Gastrointestinal toxicity was generally moderate. Peripheral neuropathy was present in 42% of the patients, although in most of them it was slight. The main radiotherapy toxicity was esophagitis grade I-II. Evaluation of response after the third chemotherapy course showed an objective response in 16 patients (48%), whereas in three patients (9%) the disease progressed during therapy. The median survival of the entire group was 13 months. Cisplatin plus vinorelbine followed by radiotherapy is an effective schedule for patients with locally advanced non-small-cell lung cancer.     

A drug revolving fund program for rural villages in the Philippines

In 1994, a community-based drug revolving fund program was introduced in 10 pilot villages in the province of Tarlac, Philippines, as a component of a health project by the provincial health office and Japan International Cooperation Agency (JICA). The purpose of the program was to set up a cooperative drug store in each community in order to regularly provide rural residents with essential drugs at affordable prices. The following are the results and findings during the first two years of operation. 1. Collaboration with a local NGO facilitated implementation and management of the program, when socio-cultural consideration was necessary. Stable and prompt procurement of drugs was secured on a contract with a commercial wholesaler in Manila. 2. Out of the 105 kinds of pharmaceuticals that were sold both in the cooperative and commercial drug stores, 83% were less expensive than the average market price, and 51% were discounted more than 25% of the market price. 3. The levy of premiums was introduced to increase the cooperative fund with the consent of each community. The amount was 0.1-0.2% of the average family income. However, regular collection of premiums was difficult due to various reasons. The practice of the sales on credit was common in all pilot villages. 4. While the knowledge of community health workers, who were in charge drug sales, was improved after training sessions on rational drug use, it was not at a sufficient level yet. 5. When assisting a community-oriented health program, an exterior organization should try to encourage the community to generate its own solutions to operational difficulties, based on the socio-cultural context in the community.     

Alterations in ultrastructural localization of growth-associated protein-43 (GAP-43) in periodontal Ruffini endings of rat molars during experimental tooth movement

It is known that orthodontic forces induce discomfort and/or abnormal sensation after application of an orthodontic appliance in patients, suggesting the adaptation of periodontal neural elements to environmental changes. However, no morphological data have been provided. The present study investigated, by immunoelectron microscopy, the localization of growth-associated protein-43 (GAP-43) in periodontal Ruffini endings in rat molars during experimental tooth movement. In the untreated control group, immunoelectron microscopy demonstrated that GAP-43-like immunoreactivity in the Ruffini endings was confined to the Schwann sheaths around the axon terminals, and was in neither the cell bodies of terminal Schwann cells nor the axon terminals themselves. Immunoelectron microscopic observation revealed alterations in the localization of GAP-43-like immunoreactivity in the periodontal Ruffini endings during experimental tooth movement. After 1 day of treatment, the cell bodies of the terminal Schwann cells associated with Ruffini endings appeared to contain immunoreaction products for GAP-43, and retained GAP-43-like immunoreactivity during tooth movement. From 5 to 7 days, a major population of the axoplasm of the periodontal Ruffini endings, which was immunonegative in control, filled the GAP-43 immunoreactions, showing a tendency to decrease in number later, and disappeared completely at 14 days. These findings suggest that orthodontic forces easily induce the remodeling of the mechanoreceptive Ruffini endings as well as the active tissue remodeling in a close relationship. Since the ultrastructural localization of GAP-43-like immunoreactivity was drastically changed in the Ruffini endings during tooth movement, GAP-43 functions as one of the key molecules in the remodeling of mechanoreceptive Ruffini endings during tooth movement.     

Three approaches for laparoscopic unroofing of simple and complicated renal cysts

We report 2 cases of simple renal cysts which were marsupialized with 2 laparoscopic approaches involving either transperitoneal, with reflection of the colon medially or dissection through the mesocolon, and a case of a multilocular renal cyst which was treated by the retroperitoneal approach. Although laparoscopic unroofing of a renal cyst is a safe and effective alternative to open surgical techniques, the transperitoneal approach should only be used for simple renal cysts. The retroperitoneal approach for complicated renal cysts may be indicated if preoperative examinations exclude the possibility of malignancy.     

Realization of one-chip-two-wavelength light sources

We proposed a vertically integrated one-chip-two-wavelength light source which consists of a separate confinement single-quantum-well (SCH-SQW) ZnCdSe/ZnSe/ZnMgBeSe heterostructure for blue–green light emitters grown on SCH-MQW InGaP/InGaAlP for red light-emitting devices.We investigated, firstly, the effect of a thin low-temperature-grown ZnSe buffer layers (LT-ZnSe) in improving ZnSe crystallinity by inserting it between the high-temperature-grown ZnSe epilayer and the GaAs substrate, secondly, the growth optimization of LT-ZnSe on tilted GaAs (0 0 1) substrate, and lastly, the molecular beam epitaxy growth and characterization of ZnCdSe/ZnSe/ZnMgBeSe quantum well structures on metal organic chemical vapor deposition (MOCVD) grown III–V red light emitters.Optically pumped lasing is achieved from II–VI and III–V laser structures on one chip at room temperature. The present results clearly show the feasibility of epitaxial integration of II–VI and III–V laser structures.