Association between the lack of teeth and the expression of myosins in masticatory muscles of microphthalmic mouse

The purposes of the present study were to elucidate the influences of the deficiency of teeth on masticatory muscles, such as the masseter, temporalis and digastric muscles and compare the influence among masticatory muscles. We analysed the expressions of myosin heavy chain (MyHC) isoform messenger RNA (mRNA) and protein in these muscles in the microphthalmic (mi/mi) mouse, whose teeth cannot erupt because of a mutation in the mitf gene locus. The expression levels of MyHC mRNA and protein in the masseter, temporalis, digastric, tibialis anterior and gastrocnemius muscles of +/+ and mi/mi mice were analysed with real‐time polymerase chain reaction and sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, respectively. The mi/mi masseter muscle at 8 weeks of age expressed 4·1‐fold (p < 0·05) and 3.3‐fold (p < 0·01) more MyHC neonatal mRNA and protein than that in the +/+, respectively; the expression level of MyHC neonatal protein was 19% of the total MyHC protein in the masseter muscle of mi/mi mice. In the digastric muscle, the expression levels of MyHC I mRNA and protein in the mi/mi mice were 4·7‐fold (p < 0·05) and 5‐fold (p < 0·01) higher than those in the +/+ mice. In the temporalis, tibialis anterior and gastrocnemius muscles, there was no significant difference in the expression levels of any MyHC isoform mRNA and protein between +/+ and mi/mi mice. These results indicate associations between the lack of teeth and the expression of MyHC in the masseter and digastric muscles but not such associations in the temporalis muscle, suggesting that the influence of tooth deficiency varies among the masticatory muscles. Copyright © 2011 John Wiley & Sons, Ltd.     

Pathological femoral fractures due to osteomalacia associated with adefovir dipivoxil treatment for hepatitis B: a case report

ABSTRACT: We present a case of a 62-year-old man who underwent total hip arthroplasty for treatment of pathologic femoral neck fracture associated with adefovir dipivoxil-induced osteomalacia. He had a 13-month history of bone pain involving his shoulders, hips, and knee. He received adefovir dipivoxil for treatment of lamivudine-resistant hepatitis B virus infection for 5 years before the occurrence of femoral neck fracture. Orthopedic surgeons should be aware of osteomalacia and pathological hip fracture caused by drug-induced renal dysfunction, which results in Fanconi's syndrome.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1600344696739249.     

Tamoxifen feeding method is suitable for efficient conditional knockout

The Cre-driver system is used to generate conditional knockout mice. Tamoxifen inducible Cre-driver mice can be used for spatiotemporal knockout by administration of the drug. A major tamoxifen administration is performed by intraperitoneal administration or oral administration. However, these forced administrations may be damaging to mice. Herein, we have demonstrated an improved method of administering tamoxifen with powdered food to mice. A mouse line expressing the tamoxifen-inducible Cre gene was used ubiquitously in this experiment to evaluate the efficiency of Cre recombination in the whole body. Our method also achieved efficient recombination without causing injury to mice. The X-gal staining intensity of the feeding method was equivalent to that of the intraperitoneal administration method. Furthermore, this method can be used for recombination before birth, or during the fetal period. We recommend researchers to employ this feeding method to administer tamoxifen to minimize the risk of injury to mice.     

Three-dimensional reconstructions of haustoria in two parasitic plant species in the Orobanchaceae

Parasitic plants infect other plants by forming haustoria, specialized multicellular organs consisting of several cell types, each of which has unique morphological features and physiological roles associated with parasitism. Understanding the spatial organization of cell types is, therefore, of great importance in elucidating the functions of haustoria. Here, we report a three-dimensional (3-D) reconstruction of haustoria from two Orobanchaceae species, the obligate parasite Striga hermonthica infecting rice (Oryza sativa) and the facultative parasite Phtheirospermum japonicum infecting Arabidopsis (Arabidopsis thaliana). In addition, field-emission scanning electron microscopy observation revealed the presence of various cell types in haustoria. Our images reveal the spatial arrangements of multiple cell types inside haustoria and their interaction with host roots. The 3-D internal structures of haustoria highlight differences between the two parasites, particularly at the xylem connection site with the host. Our study provides cellular and structural insights into haustoria of S. hermonthica and P. japonicum and lays the foundation for understanding haustorium function.

Three-dimensional image reconstruction visualized the spatial organization of cell types in the haustoria of the Orobanchaceae parasitic plants Striga hermonthica and Phtheirospermum japonicum.     

Synthesis of a Prostaglandin Intermediate and Synthesis of Dihydrojasmone and Methyl Dihydrojasmonate

The synthesis of 2-(6-methoxycarbonylhexyl)cyclopent-2-ene-1-one (5), a valuable intermediate in the synthesis of prostaglandins, is described starting from ethyl 3-oxoglutarate (1). The same reaction sequence also produces dihydrojasmone (12) and methyl dihydrojasmonate (13).     

The synthesis and biodistribution of [11C]metformin as a PET probe to study hepatobiliary transport mediated by the multi-drug and toxin extrusion transporter 1 (MATE1) in vivo

In order to develop a new positron emission tomography (PET) probe to study hepatobiliary transport mediated by the multi-drug and toxin extrusion transporter 1 (MATE1), ¹¹C-labelled metformin was synthesized and then evaluated as a PET probe. [¹¹C]Metformin ([¹¹C]4) was synthesized in three steps, from [¹¹C]methyl iodide. Evaluation by small animal PET of [¹¹C]4 showed that there was increased concentrations of [¹¹C]4 in the livers of mice pre-treated with pyrimethamine, a potential inhibitor of MATEs, inhibiting the hepatobiliary excretion of metformin. Radiometabolite analysis showed that [¹¹C]4 was not degraded in vivo during the PET scan. Biodistribution studies were undertaken and the organ distributions were extrapolated into a standard human model. In conclusion, [¹¹C]4 may be useful as a PET probe to non-invasively study the in vivo function of hepatobiliary transport and drug–drug interactions, mediated by MATE1 in future clinical investigations.     

A simple mutagenesis using natural competence in Tannerella forsythia

We report the discovery of natural competence in Tannerella forsythia and its application to targeted chromosomal mutagenesis. Keeping T. forsythia in a biofilm throughout the procedure allowed efficient DNA uptake and allelic replacement. This simple method is cost-effective and reproducible compared with the conventional protocols using broth culture and electroporation.     

Ketoacyl synthase domain is a major determinant for fatty acyl chain length in Saccharomyces cerevisiae

Yeast fatty acid synthase (Fas) comprises two subunits, α₆ and β₆, encoded by FAS2 and FAS1, respectively. To determine features of yeast Fas that control fatty acyl chain length, chimeric genes were constructed by combining FAS sequences from Saccharomyces cerevisiae (ScFAS) and Hansenula polymorpha (HpFAS), which mostly produces C16 and C18 fatty acids, respectively. The C16/C18 ratios decreased from 2.2 ± 0.1 in wild-type S. cerevisiae to 1.0 ± 0.1, 0.5 ± 0.2 and 0.8 ± 0.1 by replacement of ScFAS1, ScFAS2 and ScFAS1 ScFAS2 with HpFAS1, HpFAS2 and HpFAS1 HpFAS2, respectively, suggesting that the α, but not β subunits play a major role in determining fatty acyl chain length. Replacement of phosphopantetheinyl transferase (PPT) domain with the equivalent region from HpFAS2 did not affect C16/C18 ratio. Chimeric Fas2 containing half N-terminal ScFas2 and half C-terminal HpFas2 carrying H. polymorpha ketoacyl synthase (KS) and PPT gave a remarkable decrease in C16/C18 ratio (0.6 ± 0.1), indicating that KS plays a major role in determining chain length.     

Syntheses and preventive effects of analogues related to 1α,25-dihydroxy-2β-(3-hydroxypropoxy)vitamin D3 (ED-71) on bone mineral loss in ovariectomized rats

Analogues related to 1α,25-dihydroxy-2β-(3-hydroxypropoxy)vitamin D₃ (ED-71) (2), 26,27-dimethyl ED-71 (3) and 26,27-diethyl ED-71 (4), were synthesized from lithocholic acid (5). In the study of the preventive effects of these analogues and ED-71 (2) on bone mineral loss in ovariectomized rats, 26,27-dimethyl ED-71 (3) showed the most potent activity.