1α,25-dihydroxyvitamin D3 [Calcitriol or 1,25(OH)₂D₃] is an important active metabolite involved in multiple functions but its calcemic effect in vivo limits its therapeutic applications. On the other hand, 22-oxa-1α,25-dihydroxyvitamin D₃ (22-oxacalcitriol or 22-Oxa-1α,25-D₃), a low calcemic analog of vitamin D3 (VitD3), has been widely used as a drug for the secondary hyperparathyroidism. Here, we investigated immunomodulating effect of these two VitD3 derivatives on the differentiation of type-1 immunoregulatory cells such as dendritic cells (DC1), cytotoxic T cells (Tc1) and helper T cells (Th1). BALB/c mouse bone marrow-derived DC (BMDC1) induced by culture with Th1 condition (GM-CSF, IL-3, IL-12 and IFN-γ) expressed higher levels of MHC Class I and Class II molecules and co-stimulatory molecules compared with BMDC0 induced by neutral condition (GM-CSF + IL-3). In addition, BMDC1 showed stronger immunostimulating activity to induce alloantigen (H-2^d)-specific cytotoxic T lymphocytes (CTL) compared with BMDC0. However, if VitD3 derivatives were added into the culture for BMDC1 induction, the expression of functional molecules and type-1 IFNs were greatly inhibited. Moreover, VitD3 derivative-treated BMDC1 lost their immunostimulating activity to induce alloantigen-specific IFN-γ-producing Tc1. In addition, it was demonstrated that the addition of VitD3 derivatives inhibited the differentiation of IFN-γ-producing Th1 cells from ovalbumin (OVA)-specific naive Th cells, while it rather augmented the differentiation of IL-4- or IL-10-producing Th2 cells. There was no significant difference in immunomodulating activity between 1,25(OH)₂D₃ and 22-Oxa-1α,25-D₃. Thus, VitD3 derivatives are demonstrated to inhibit the functional differentiation of DC1, Tc1 and Th1 cells, which play a critical role in type-1 cellular immune responses.

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We assessed the stress relief effect of spa bathing by measuring sensitive salivary stress markers, cortisol and chromogranin A (CgA). From 12 healthy males, saliva samples were collected immediately before and after spa bathing, and 30 min after that. Salivary cortisol and CgA levels were determined by ELISA. Salivary cortisol levels decreased after spa bathing. This tendency was more pronounced in individuals with higher levels of stress. The high-stress group showed lower salivary CgA levels after spa bathing, while the low-stress group higher salivary CgA levels in the same condition. These findings suggest that the spa bathing has a moderate affect on the stress relief.

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The gastrointestinal HCO₃^- secretion functions to limit the mucosal acid damage due to HCl secreted in the stomach or organic acids produced in the large intestine. We studied HCO₃^- secretion in the mouse large intestine with isolated tissues mounted in chambers by using pH stat method. Addition of Cl^- to the mucosal side caused an increase in HCO₃^- secretion in the cecum and distal colon but had little, if any, effect in the proximal colon. In agreement with this, mucosal surface pH was higher in the cecum and distal colon than in the proximal colon. The Cl^--induced HCO₃^- secretion in the cecum was inhibited by 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB, mucosal addition), but not by DIDS (mucosal or serosal), acetazolamide, amiloride (serosal) or glibenclamide (mucosal). Removal of Na⁺ or addition of propionate had hardly any effect on the Cl^--induced HCO₃^- secretion. These results suggest that a NPPB-sensitive, DIDS-resistant Cl^-/ HCO₃^- exchanger is present in the apical membrane, and mediates Cl^--dependent HCO₃^- secretion. This process is probably mainly responsible for the formation of the high pH at the mucosal surface.

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In most subjects with spinal cord injury, the spinal neurons below the level of injury are spared. Therefore, it is conceivable that the skeletal muscles innervated by these spinal nerves can be activated by applying therapeutic magnetic stimulation along the dorsal spine. The purpose of this study was to evaluate the ability of magnetic stimulation to prevent acute muscle atrophy in rats after hindlimb suspension. Forty adult male Wistar rats were randomly assigned to stimulated and non-stimulated (control) groups. Their hindlimbs were unweighted using a suspension method, causing muscle atrophy. In the stimulation group, magnetic stimulation (20 Hz, 60 min per day) was applied to the sciatic nerve for 10 days. After the stimulation period, the tibialis anterior (TA) and extensor digitorum longus (EDL) were surgically removed and histologically measured. The lesser diameters of type 1, 2A, and 2B muscle fibers were significantly greater in the stimulated group than in the non-stimulated group for both the TA and EDL (p < 0.05). The mean difference in lesser fiber diameter was 20% (range, 14%-27%). These results suggest that therapeutic magnetic stimulation is an effective method of preventing muscle atrophy.

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Simvastatin acid (SVA) has been reported to stimulate bone formation with increased expression of BMP-2. Therefore, immobilization of SVA onto dental implants is expected to promote osteogenesis at the bone tissue/implant interface. The aim of this study was to evaluate the immobilization behavior of SVA onto titanium (Ti), O₂-plasma treated titanium (Ti + O₂), thin-film coatings of hexamethyldisiloxane (HMDSO), and O₂-plasma treated HMDSO (HMDSO + O₂) by using the quartz crystal microbalance-dissipation (QCM-D) technique. HMDSO surfaces were activated by the introduction of an OH group and/or O₂-functional groups by O₂-plasma treatment. In contrast, titanium surfaces showed no appreciable compositional changes by O₂-plasma treatment. The QCM-D technique enabled evaluation even at the adsorption behavior of a substance with a low molecular weight such as simvastatin. The largest amount of SVA was adsorbed on O₂-plasma treated HMDSO surfaces compared to untreated titanium, HMDSO-coated titanium, and O₂-plasma treated titanium. These findings suggested that the adsorption of SVA was enhanced on more hydrophilic surfaces concomitant with the presence of an OH group and/or O₂-functional group resulting from the O₂-plasma treatment, and that an organic film of HMDSO followed by O₂-plasma treatment is a promising method for the adsorption of SVA in dental implant systems.

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Muscarinic cholinergic receptor activation provokes cGMP formation in parotid acinar cells. We investigated the involvement of Ca²⁺/calmodulin-dependent cyclic nucleotide phosphodiesterase (PDE1) in cGMP breakdown in rabbit parotid acinar cells. The muscarinic agonist carbachol stimulated cGMP formation in the cells. The carbachol-induced cGMP formation was enhanced in the presence of 8-methoxymethyl-3-isobutyl-1-methylxanthine (MM-IBMX), a PDE1 inhibitor. cGMPPDE activity in rabbit parotid acinar cells was reduced by about 25% in the absence of Ca²⁺/ calmodulin or in the presence of MM-IBMX. Ca²⁺/calmodulin-dependent cGMP-PDE in rabbit parotid acinar cells was purified using Calmodulin-Sepharose 4B and Mono Q ion-exchange column chromatography. Two dominant fractions with cGMP-PDE activity, referred to as the P-1 and P-2 fractions, were eluted from the Mono Q ion-exchange column. The Km values for cGMP of PDE in the P-1 and P-2 fractions were 0.82 μM and 0.40 μM, respectively, which were much lower than that for cAMP. The EC₅₀ for Ca²⁺ and calmodulin of PDEs in the P-1 and P-2 fractions were 458 nM and 426 nM, respectively, and 32 nM and 137 nM, respectively. Protein bands that crossreacted with anti-PDE1A antibody were detected. These results suggest that Ca²⁺/calmodulin-dependent PDE, PDE1A, is involved in cGMP breakdown in rabbit parotid acinar cells.

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We observed that patients with lymphocytopenia have a cold external body temperature—especially the abdomen, hips and extremities—as recognized by palpation. Such patients were recommended to use a hot water bottle especially for cold extremities for the purpose of improving “chill”. Six cases of lymphocytopenia diagnosed by previous medical doctors within two weeks before consulting our clinic are described in this study. The patients warmed their trunks and extremities by hot water bottles for as long as possible not only while sleeping but also during the daytime. There was no remarkable change in leukocyte count, but granulocytes significantly decreased in number (from 6,716 ± 4,032 to 5,467 ± 2,660) (p = 0.013), and lymphocytes significantly increased from 718 ± 211 to 1,845 ± 406 (p = 0.0017). It is important for clinicians to recognize that such an easy method can improve lymphocytopenia.

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