Distinct Functions of the Atypical Terminal Hydrophilic Domain of the HKT Transporter in the Liverwort Marchantia polymorpha

K+/Na+ homeostasis is important for land plants, particularly under salt stress. In this study, the structure and ion transport properties of the high-affinity K+ transporter (HKT) of the liverwort Marchantia polymorpha were investigated. Only one HKT gene, MpHKT1, was identified in the genome of M. polymorpha. Phylogenetic analysis of HKT proteins revealed that non-seed plants possess HKTs grouped into a clade independent of the other two clades including HKTs of angiosperms. A distinct long hydrophilic domain was found in the C-terminus of MpHKT1. Complementary DNA (cDNA) of truncated MpHKT1 (t-MpHKT1) encoding the MpHKT_Δ596-812 protein was used to examine the functions of the C-terminal domain. Both MpHKT1 transporters fused with enhanced green fluorescent protein at the N-terminus were localized to the plasma membrane when expressed in rice protoplasts. Two-electrode voltage clamp experiments using Xenopus laevis oocytes indicated that MpHKT1 mediated the transport of monovalent alkali cations with higher selectivity for Na+ and K+, but truncation of the C-terminal domain significantly reduced the transport activity with a decrease in the Na+ permeability. Overexpression of MpHKT1 or t-MpHKT1 in M. polymorpha conferred accumulation of higher Na+ levels and showed higher Na+ uptake rates, compared to those of wild-type plants; however, phenotypes with t-MpHKT1 were consistently weaker than those with MpHKT1. Together, these findings suggest that the hydrophilic C-terminal domain plays a unique role in the regulation of transport activity and ion selectivity of MpHKT1.

Development of 19F-NMR chemical shift detection of DNA B–Z equilibrium using 19F-NMR

The DNA conformational changes such as B-formed, Z-formed, and single stranded DNA, were detected in one of ¹⁹F-NMR measurements using a fluorine-labeled nucleobase.

Limb salvage using bypass to the perigeniculate arteries

OBJECTIVE

To describe bypass to perigeniculate vessels for limb salvage.

DESIGN

Retrospective cohort study.

MATERIAL AND METHODS

Between 1995 and 2009, 47 bypass procedures to perigeniculate collateral arteries were performed in 46 patients (15 women, 31 men; median age, 68 years). All patients presented with critical ischaemia (tissue loss in 87.5%, rest pain in 12.5%). Mean ankle brachial index was 0.27 ± 0.17. The site of distal anastomosis was the descending genicular artery (DGA) in 23 bypasses (1 bilateral) and the medial sural artery (MSA) in 24. Proximal anastomosis was to the external iliac artery in 2 cases, common femoral artery in 23 cases, superficial femoral artery in 8 cases, deep femoral artery in 8 cases, above-knee poplitaeal artery in 2 cases, and previous graft in 4 cases.

RESULTS

There were four deaths during the immediate postoperative period. Mean follow-up duration was 27 months. Ten patients required major amputation. Mean ankle brachial index post-operatively was 0.60 ± 0.21. At 3 years, primary patency was 74.7 ± 7%, secondary patency was 83.4 ± 8%, and the limb salvage and survival rates were 73.5 ± 7% and 77.4 ± 7%, respectively.

CONCLUSION

Bypass to perigeniculate arteries is a viable treatment option for critical limb ischaemia in selected patients.

Visual dominance in amending the directional parameter of feedforward control

The authors examined visual dominance between trials in which the movement program was amended (i.e., off-line processing). Weighting between visual and proprioceptive feedback was examined in a trial-by-trial analysis of the directional parameter of feedforward control. Eight participants moved a cursor to a target displayed on a computer screen by manipulating a hand-held stylus on a digitizing tablet. In the first 30 trials, the cursor followed the stylus movement (practice condition). In the next 30 trials, the directional error of the stylus movement was presented in the opposite direction (reversal condition). Subjects knew the presence and the nature of the reversal. In the last 10 trials, the reversal was withdrawn (transfer condition). Directional error of feedforward control was relatively small in the practice condition, and it increased gradually in 1 of 2 directions as trials proceeded in the reversal condition. Positive aftereffect was observed in the transfer condition. A constant increment of the directional error indicated that both visual and proprioceptive feedback are registered, with higher weight on vision, and that weighting between those inputs is determined automatically or is fixed without any strategic control.

Advanced glycation end products induce expression of vascular endothelial growth factor by retinal Muller cells

Recent studies have suggested that advanced glycation end products (AGEs) are involved in the development of diabetic complications. To assess the pathogenic role of AGEs and vascular endothelial growth factor (VEGF) in the development of retinal neovascularization in diabetic retinopathy, we investigated the effect of AGEs on induction of VEGF by retinal Muller cells and measured AGE and VEGF concentrations in the vitreous of patients with proliferative diabetic retinopathy (PDR) and nondiabetic patients. The expression of VEGF mRNA and the production of VEGF protein by cultured Muller cells were enhanced by the presence of AGEs. The vitreous concentrations of AGEs and VEGF were both elevated in patients with PDR compared with patients without diabetes (P < 0.01). There was a moderate positive correlation between the levels of crossline and VEGF (r=0.698, P < 0.01). Elevation of AGEs in the vitreous may promote intraocular neovascularization in diabetic retinopathy through production of VEGF from Muller cells.

Preincubation of thymocytes with 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7) induces apoptosis in non-stimulated thymocytes

1-(5-Isoquinolinesulfonyl1)-2-methylpiperazine hydrochloride (H-7), an inhibitor of protein kinases, has been shown to inhibit the thymocyte apoptosis induced by various apoptogenic agents. In the present study, when mouse thymocytes were pretreated with H-7, washed, and cultured for an additional time, apoptosis was induced depending on the preincubation time and the dose of H-7. The protein kinase C activity in the H-7-pretreated and -washed cells was not altered, suggesting that an alteration of a certain PKC isoform is related to both the triggering and the progression of apoptosis.

Effects on archery performance of manipulating metamotivational state and felt arousal

This study investigated the effect of the four different combinations of metamotivational state and felt arousal level (telic-low, paratelic-low, telic-high, paratelic-high) on archery performance. Skilled, average, and novice archers (n = 28) were voluntary subjects, randomly divided into 2 groups, balanced for ability. Each group performed 2 out of the 4 experimental conditions. In this reversal theory-based field experiment, telic and paratelic metamotivational states and arousal level were manipulated prior to archery performance. The hypothesis that archery performance would be superior under telic-low arousal conditions was rejected, but evidence pointed to the possible importance of hedonic tone in performance. Post boc analysis showed differences between combined high (telic-low, paratelic-high) and combined low (telic-low, paratelic-high) hedonic-tone groups which fell short of significance. This observation is taken as justification for further exploration of the relationship between hedonic tone and sports performance.

Staurosporine-induced thymocyte apoptosis is inhibited by herbimycin A, a specific inhibitor of protein tyrosine kinase

When mouse thymocytes were incubated with staurosporine at low doses (1-100 nM), increased tyrosine phosphorylation of proteins with a molecular weight of 31-34 kD in the detergent-soluble fraction was observed, together with an increase in internucleosomal DNA fragmentation. Incubation with staurosporine for 6 h was enough to trigger and progress of apoptosis. Herbimycin A, a specific inhibitor of protein tyrosine kinases, and cycloheximide, an inhibitor of protein synthesis, reduced the amount of the phosphotyrosine proteins, this being followed by the inhibition of DNA fragmentation and cell death, suggesting a close relationship between protein tyrosine phosphorylation and the induction of apoptosis by staurosporine.

Purification, characterization, and amino acid sequence of foxtail millet trypsin inhibitor III

One of the major trypsin inhibitors of foxtail millet, Setaria italica, was purified from a seed extract to an electrophoretically homogeneous protein by methods including chromatofocusing and affinity chromatography. This inhibitor (FMTI-III) was shown to be specific and single-headed for trypsin. The molecular weight and the amino acid composition together with the above nature were identical with those of another major trypsin inhibitor (FMTI-II) previously purified from foxtail millet grain. Sequence analysis of FMTI-III indicated that the protein contains 67 amino acid residues, the sequence of which is the same as that of FMTI-II except for the replacement of the C-terminal glutamine by glutamic acid. This single amino acid substitution had no effect on inhibitor-enzyme association.

The complete amino acid sequence of a major trypsin inhibitor from seeds of foxtail millet (Setaria italica)

The complete amino acid sequence of a major trypsin inhibitor (FMTI-II) from seeds of foxtail millet (Setaria italica) was determined by analysis of peptides derived from the reduced and S-carboxymethylated protein by digestion with TPCK-trypsin and Staphylococcus aureus V8 protease. FMTI-II consists of 67 amino acid residues, including 10 half-cystine residues which are involved in 5 disulfide bridges in the molecule. The established sequence had a high degree of homology to Bowman-Birk type inhibitors from leguminous and gramineous plants. The trypsin reactive-site peptide bond in FMTI-II also appears to be Lys (16)-Ser (17) by comparison with these sequences.

A new resuscitation fluid "stabilized hemoglobin" preparation and characteristics

A new oxygen carrier for use as a blood substitute was prepared and characterized in vitro. Pyridoxylated hemoglobin, which was obtained by the reaction of human hemoglobin with pyridoxal-5-phosphate, was modified by alpha-carboxymethyl, omega-carboxymethoxyl polyoxyethylene (POE) of the molecular weight 3600 daltons. In order to eliminate viruses and nucleic acids possibly contaminated, the hemoglobin solution was purified by ultrafiltration with a membrane of the nominal molecular weight limit 300 Kdaltons. Furthermore POE conjugated pyridoxylated hemoglobin was treated with 20% ethanol to inactivate viruses. A concentration of hemoglobin, which is incorporated in the conjugate, of the final product was fixed at 6% to make normovolemic exchange transfusion possible. In consideration of the stability during transporting and storage, lyophilized product was selected as a final form ("Stabilized Hemoglobin"). "Stabilized hemoglobin" could be stored in a refrigerator over one year within the acceptable methemoglobin increase. (15%) Viscosity of Stabilized Hemoglobin solution was determined at 2.4 centipoise and is almost half of whole blood and therefore this will be useful not only in resuscitation but also in improvement of microcirculation.

Treatment of ordinary and penicillinase-producing strains of Neisseria gonorrhoeae in Mexico City

Since being recognized in 1976 and 1983, respectively, penicillinase-producing strains of Neisseria gonorrhoeae (PPNG) and chromosomally mediated resistance (CMRNG) have attained a worldwide distribution. The high endemicity of both types of resistance in some regions precludes the continued routine use of procaine penicillin (APPG) as treatment for gonorrhea. In this study, we have evaluated 72/216 men with uncomplicated gonococcal urethritis at the venereal clinic in Mexico City. These men were part of a blinded randomized comparative study for treatment with group (P) penicillin having 33 patients and group (S) spectinomycin having 39. Efficacy with (P) was 24/33 (72.7%); nine failures retreated and were cured with spectinomycin. Efficacy with (S) was 35/39 (89.7%); four failures retreated and were cured with cefotaxime. We found correlation between MICs and resistance; all the strains with MICs of greater than or equal to 1.0 mcg/ml of penicillin failed to be cured, the MICs of greater than or equal to 32 mcg/ml of spectinomycin failed to be cured. The overall resistance to both regimens was 23/72 to penicillin (31.9%) (22 PPNG and one CMRNG) and 4/72 (5.5%) to spectinomycin.