Real‐Time Observations of Oriented Crystallization of Poly(ε‐caprolactone) Thin Film,Induced by an AFM Tip

Atomic force microscopy (AFM) was used for modifying the surface structures of poly(ε‐caprolactone) (PCL) thin film. Oriented growth of PCL crystals at a desired area of the film surface was induced by scanning with a strong, normal load. PCL crystals were first grown edge‐on from the induction line and then their orientation changed to flat‐on at a lamellar length. The effects of molecular weight, crystallization temperature, scanning rate, and normal load on the AFM‐tip‐induced crystallization were examined. The growth kinetics of lamellar crystals in the AFM‐tip‐induced crystallization was the same as that in spherulitic crystallization. It was found that the formation of precursors strongly depends on the applied tip load and is facilitated when the applied load is higher than a threshold.

     

Gomisin N Decreases Inflammatory Cytokine Production in Human Periodontal Ligament Cells

Gomisin N, which is a lignan isolated from Schisandra chinensis, has some pharmacological effects. However, the anti-inflammatory effects of gomisin N on periodontal disease are uncertain. The aim of this study was to examine the effect of gomisin N on inflammatory mediator production in tumor necrosis factor (TNF)-α-stimulated human periodontal ligament cells (HPDLC). Gomisin N inhibited interleukin (IL)-6, IL-8, CC chemokine ligand (CCL) 2, and CCL20 production in TNF-α-stimulated HPDLC in a dose-dependent manner. Moreover, we revealed that gomisin N could suppress extracellular signal-regulated kinase (ERK) and c-Jun N terminal kinase (JNK) phosphorylation in TNF-α-stimulated HPDLC though protein kinase B (Akt) phosphorylation was not suppressed by gomisin N treatment. In summary, gomisin N might exert anti-inflammatory effects by attenuating cytokine production in periodontal ligament cells via inhibiting the TNF-α-stimulated ERK and JNK pathways activation.     

Genetic and clinical analysis in a Chinese parkinsonism-predominant spinocerebellar ataxia type 2 family

Parkinson's disease is a degenerative central nervous system disorder that often impairs motor skills, speech and other functions. We discovered a large Chinese family showing primarily parkinsonism symptoms with autosomal dominant inheritance. Six affected individuals in the family showed typical parkinsonism symptoms, including pill-rolling tremor. Two other affected individuals showed cerebellar ataxia symptoms. A whole-genome scan using the 50K single nucleotide polymorphism array with three different linkage methods detected two positive regions on chromosome 12q24.1 and 5q13.3. The ATXN2 gene, responsible for spinocerebellar ataxia type 2 (SCA2) was located precisely in the center of the positive region on chromosome 12. Further analysis of SCA2 revealed heterozygous pathological CAG expansions in the family. The affected individuals' symptoms were typical of parkinsonism, but complex. Inverse correlation between CAG repeat size and age of onset is not obvious in this pedigree. This parkinsonism-predominant SCA2 family shared the same disease gene locus with other 'standard' SCA2 families, but it is possible that variations in one or more modifier genes might account for the parkinsonism-predominant SCA2 predisposition observed in this pedigree.     

Morphological divergence in the curvature of human femoral diaphyses: Tracing the central mass distributions of cross-sections

The diaphysis of the human femoral bone has a physiological anterior curvature; additionally, there is a curvature to the medial side or lateral side. In addition to compression stress from gravity during standing, walking, and running, these bones are continuously exposed to complex stresses from the traction forces of the various strong muscles attached to them. The femoral diaphysis is subjected to these mechanical stresses, and the direction and size of its curvature are defined according to Wolff's law and the mechanostat theory of Frost. The purpose of this study was to quantitatively evaluate the curvature of the femoral diaphysis in Japanese skeletons by determining the curve connecting the central mass distributions (CMD) of cross-sectional images. A total of 90 right femora (46 males and 44 females) were randomly selected from modern Japanese skeletal specimens. Full-length images of these bones were acquired using a clinical computed tomography scanner. The range between the lower end of the lesser trochanter and the adductor tubercle of each femur was divided at regular intervals to obtain ten planes, and nine levels were analyzed. The CMD curve was determined by connecting the CMDs of each of the nine cross-sections. First, the CMD of a cross-section in each of the nine slices was calculated, and the nine trajectories were superimposed from above. Then, by converting the shape of the entire CMD curve to superimpose the coordinates of the endpoint on the starting point, a closed arc representing the curvature of the femur was determined. For both males and females, the patterns varied from mostly medial to largely lateral curvature. The size of the curvature also varied for individuals. By analyzing only the coordinates of the vertex of the CMD curve of each femoral bone, the outlines of the diaphyseal curvatures could be recognized. The femora were thereby divided into two groups: medial bending and lateral bending. Considering males and females together, the number in the lateral-curvature group (n = 51) was larger than that in the medial-curvature group (n = 39). Moreover, the average age of the lateral-curvature group was significantly higher than that of the medial-curvature group (p < 0.05). In males, with an increase in the cortical bone proportion of the cross-sectional area, the anterior vertex of diaphyseal bending tended to be more prominent. This cortical proportion was significantly higher in the medial-curvature groups than in the lateral-curvature group (p < 0.01). The phenomena observed in this study may be related to pathophysiologies such as atypical fractures of the femur and osteoarthritis of the knee joints.     

Epitope-specific impairment of production of antibody against merozoite surface glycoprotein 1 of Plasmodium falciparum in symptomatic patients with malaria

We analyzed the relationships between levels of antibody specific for merozoite surface glycoprotein-1 (MSP1) of Plasmodium falciparum and clinical manifestations in humans. We prepared recombinant MSP1 proteins representing block 3 (M3), block 6 (M6), blocks 1–6 (M1/6), and block 17. When we divided the slide-positive individuals in Guadalcanal into symptomatic and asymptomatic groups, the former group showed lower IgG levels against M6 and block 17, but not against M3, than did the asymptomatic group (P < 0.01). The possibility of nonspecific suppression was unlikely, given that the levels of antibody against poliomyelitis virus observed in the two groups were almost the same. Among the IgG subclasses tested, production of cytophilic IgG₃ seemed to be dominant. When we analyzed epitopes recognized by antibodies against block 17, a peptide (SSSNFLGIS) was preferentially recognized by sera from asymptomatic individuals. These results suggest that clinical symptoms occurring during falciparum malaria seem to be associated with the development of levels of antibody against particular epitopes on MSP1, which is under the control of an immunoregulatory mechanism. Received: 1 October 1999 / Accepted: 21 October 1999     

Isolation of a human monoclonal antibody with strong neutralizing activity against diphtheria toxin

We isolated a human monoclonal antibody against diphtheria toxin (DT). It bound to fragment B with a binding activity (K_d) of 3.01 nM. The neutralizing activity assayed by the rabbit skin test was estimated to be 73,600 IU/g. This could be used as a therapeutic drug against DT in place of the traditional equine sera.     

Induction of protumoral CD11chigh macrophages by glioma cancer stem cells through GM‐CSF

Cancer stem cells (CSCs) are maintained under special microenvironment called niche, and elucidation and targeting of the CSC niche will be a feasible strategy for cancer eradication. Tumor‐associated macrophages (TAMs) are known to be involved in cancer progression and thus can be a component of CSC niche. Although TAMs are known to play multiple roles in tumor progression, involvement of CSCs in TAM development fully remains to be elucidated. Using rat C6 glioma side population (SP) cells as a model of glioma CSCs, we here show that CSCs induce the TAM development by promoting survival and differentiation of bone marrow‐derived monocytes. CSC‐induced macrophages can be separated into two distinct subsets of cells, CD11c^low and CD11c^high cells. Interestingly, only the CD11c^high subset of cells have protumoral activity, as shown by intracranial transplantation into immune‐deficient mice together with CSCs. These CD11c^high macrophages were observed in the tumor formed by co‐transplantation with CSCs. Furthermore, CSCs produced GM‐CSF and anti‐GM‐CSF antibody inhibited CSC‐induced TAM development. In conclusion, CSCs have the ability to self‐create their own niche involving TAMs through CSC‐derived GM‐CSF, which can thus be a therapeutic target in view of CSC niche disruption.     

The spinal antinociceptive effect of kyotorphin in mice: involvement of the descending noradrenergic and serotonergic systems

The role of descending monoaminergic systems in the antinociceptive effect of kyotorphin (Tyr-Arg, KTP) was investigated in mice by means of the tail-pinch test. We compared this effect with that of the delta-opioid receptor agonist [D-Pen(2,5)]-enkephalin (DPDPE). The antinociceptive effect of KTP and DPDPE injected intrathecally (i.t.), with ED(50) values of 26 and 0.030 microg/mouse, respectively, was completely abolished by co-administration of the adrenoceptor antagonist phentolamine and the serotonin receptor antagonist methysergide. Moreover, the activity of i.t. KTP and DPDPE was also antagonized by reserpine, 6-hydroxydopamine plus nomifensine, and p-chlorophenylalanine treatment. These results suggest that activation of both the descending noradrenergic and serotonergic systems is involved in the antinociceptive effect of spinally administered KTP against mechanical noxious stimulation, similar to the effect of DPDPE.