Inorganic polyphosphate stimulates lon-mediated proteolysis of nucleoid proteins in Escherichia coli

Inorganic polyphosphate (polyP) accumulates in response to amino acid starvation in Escherichia coli. Previously, we found that the complex formation of Lon with polyP stimulates proteolysis of free ribosomal proteins. In the current studies, we examined the effects of polyP on the degradation of major nucleoid proteins. Fusions of green fluorescent protein with HimA, Fis, HupA, and HupB were clearly associated with polyP in vivo. Lon degraded His-tagged HimA protein only in the presence of polyP in vitro as well as in vivo. Whereas, when HimA and HimD formed a heterodimer, Lon could not degrade it even in the presence of polyP. In addition, Lon degraded His-tagged Fis protein in the presence of polyP. However, in vivo, Lon did not efficiently degrade the Fis protein even when cells accumulated polyP in response to amino acid starvation. It appears that this is due to tighter binding of Fis to DNA than to polyP and resistance of the DNA-Fis to Lon-mediated proteolysis. Indeed, we found that at least a five-fold excess of polyP was necessary to displace DNA from the DNA-Fis complex. Furthermore, Lon degraded His-tagged HupA protein efficiently in the presence of polyP. We also showed that degradation of the translational initiation factor InfC depends on polyP.

Off-pump CABG with synchronized arterial flow ensuring system

PURPOSE

We developed a synchronized, arterial-flow, ensuring system to perform coronary anastomoses safely without any ischemia-related event.

DESCRIPTION

Arterial blood is removed from the femoral artery. The resulting blood passes a switching valve and is pumped out to a syringe pump. This pump controller provides pulsatile arterial blood flow synchronized with the diastolic phase on an electrocardiogram. The arterial blood is perfused to the coronary artery through a fine flexible cannula during anastomosis.

EVALUATION

From February 1999, 524 consecutive patients were operated on using the synchronized arterial flow ensuring system. Mean duration for each anastomosis was 7.6 +/- 3.3 minutes (range, 4 to 20 min). There were no intraoperative fatal arrhythmias, ventricular arrhythmias, or short-run or hemodynamic deterioration during anastomoses. No hospital death was observed, and postoperative myocardial infarction occurred in 2 patients (0.4%). Postoperative angiography showed a 98.1% patency rate.

CONCLUSIONS

The early clinical and angiographical results for off-pump CABG with the synchronized arterial flow ensuring system were excellent without mortality. We believe that off-pump CABG can be more safely performed using the synchronized arterial flow ensuring system based on our favorable results.

Robotic Replacement of the Descending Aorta in Human Cadaver

Robot-assisted replacement of the thoracic aorta was performed in a human cadaver. Temporary shunt bypass was established by inserting a left axillary artery catheter and directing it through the aortic arch toward the right femoral artery through the abdominal aorta. The technique utilized the da Vinci surgical system inserted through the 4-cm supramammary working port and two additional thoracoscopic ports. The working port allowed the introduction of an endoscope, endoscopic instruments, and artificial graft and suture materials. The aorta was dissected using the robotic instruments and was clamped with two transthoracic clamps. After transaction of the aorta, a 20-mm polytetrafluoroethylene graft was cut and an end-to-end anastomosis was then performed with running 3-0 Prolene sutures with robotic instruments. The robotic system provides superior optics and allows for enhanced dexterity. Minimally invasive robotic replacement of the descending aorta is an effective procedure and may add benefits for both surgeon and patients.

[Quality of life of long-term survivors of surgically treated lung cancer]

Quality of life (QOL) of long-term survivors (more than 3 years after surgery) of primary non-small cell lung cancer was studied. QOL was analyzed using European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, 30-Item version 3.0 (QLQ-C30) and Hospital Anxiety and Depression Scale (HADS). Sixty of 91 patients (66%) participated in this study 87 +/- 5 (38-172) months postoperatively. In QLQ-C30, calculated scores of physical (84.0 +/- 2.4), role (81.3 +/- 3.6), cognitive (79.7 +/- 2.6), emotional (86.8 +/- 1.9), and social (91.0 +/- 1.9) functioning, and global QOL (72.6 +/- 2.9) were obtained. Calculated HADS A (anxiety) was 3.3 +/- 0.3 and HADS D (depression) was 4.0 +/- 0.4. Postoperative follow-up duration was correlated with financial impact only. QOL of long-term survivors was influenced by gender histology, marital status, employment status, and academic carrier.

Experimental Study of Aortic Anastomosis Using a Circular Stapling Device in the Porcine Model

OBJECTIVES

The aim of this study was to assess the strength (pressure resistance) and histological findings of aortic anastomoses performed using a circular stapling device.

MATERIALS AND METHODS

A circular stapling device was used for anastomosing a porcine aorta and a Dacron graft. The maximum pressure resistance of the anastomotic site of a porcine aortic specimen and a Dacron graft was examined (n=10). A porcine aorta with Dacron graft was anastomosed to a beating heart, and pressure overload was induced by adrenaline (n=5). Specimens of the anastomotic sites were harvested after 14 days and examined histologically.

RESULTS

The maximum pressure resistance of the anastomotic site was 427.3+/-34.4 (375-511) mmHg. No anastomotic sites leaked as a result of pressure overloading at 227.6+/-21.1 (201-260) mmHg. Histologically, good incorporation and cell coverage were observed, and the inner surfaces of the anastomotic sites were smooth and without stenoses.

CONCLUSIONS

Aortic anastomosis using a circular stapling device is feasible and worthy of further investigation.

Switching fuzzy controller design based on switching Lyapunov function for a class of nonlinear systems

This paper presents a switching fuzzy controller design for a class of nonlinear systems. A switching fuzzy model is employed to represent the dynamics of a nonlinear system. In our previous papers, we proposed the switching fuzzy model and a switching Lyapunov function and derived stability conditions for open-loop systems. In this paper, we design a switching fuzzy controller. We firstly show that switching fuzzy controller design conditions based on the switching Lyapunov function are given in terms of bilinear matrix inequalities, which is difficult to design the controller numerically. Then, we propose a new controller design approach utilizing an augmented system. By introducing the augmented system which consists of the switching fuzzy model and a stable linear system, the controller design conditions based on the switching Lyapunov function are given in terms of linear matrix inequalities (LMIs). Therefore, we can effectively design the switching fuzzy controller via LMI-based approach. A design example illustrates the utility of this approach. Moreover, we show that the approach proposed in this paper is available in the research area of piecewise linear control.

Switching Model Construction and Stability Analysis for Nonlinear Systems

This paper presents switching model construction and stability analysis for a class of nonlinear systems. A switching fuzzy model newly developed in this paper is employed to represent the dynamics of a nonlinear system. A key feature of the switching fuzzy model construction is to find the so-called minimum distance sector by solving a nonlinear optimization problem. Next, we discuss the stability of a switching fuzzy model. To take advantage of the switching fuzzy model, we introduce a piecewise Lyapunov function that mirrors its structure. We show that the piecewise Lyapunov function approach provides less conservative results for the typical quadratic Lyapunov function approach. Illustrative examples demonstrate the utility of the switching model construction and the stability analysis.

Distal Embolus Protection With an Intra-Aortic Filter During Stent-Graft Repair of a Severely Atherosclerotic Thoracic Aortic Aneurysm

PURPOSE

To assess the technical feasibility and efficacy of distal embolus protection with an intra-aortic filter during stent-graft repair in a patient diagnosed with a shaggy aorta.

TECHNIQUE

In a 75-year-old man with a severely atherosclerotic thoracic aortic aneurysm, stent-graft repair was combined with transposition of the arch branches to the ascending aorta under thoracotomy. A filtration-type embolus protection device with a nitinol basket and polyester fabric was introduced through a 12-F sheath and opened in the supraceliac aorta during the stent-graft procedure; it was safely pulled back into the sheath after the stent-grafts were implanted. The stent-graft repair was successful, and abundant atheromatous debris was captured in the filter. Neither procedure-related embolic events nor neurological deficits were observed.

CONCLUSIONS

Use of the intra-aortic filter device to prevent distal embolism during thoracic stent-graft repairs may be feasible and efficacious in severely atherosclerotic patients.

Chemotaxis of the nematode Caenorhabditis elegans toward cycloheximide and quinine hydrochloride

We investigated the chemotaxis of the nematode Caenorhabditis elegans toward cycloheximide, denatonium benzoate, 6-n-propyl-2-thiouracil, and quinine hydrochloride. Interestingly, C. elegans was strongly attracted to cycloheximide, while avoiding quinine hydrochloride. This is the first report thus far to describe the chemotactic responses of C. elegans toward bitter tastants for humans.

Cloning and characterization of Pseudomonas putida genes encoding the phosphate-specific transport system

The pstSCAB genes of Pseudomonas putida PRS2000, encoding the phosphate (Pi)-specific transport (Pst) system, were cloned. The pstS gene of Pseudomonas aeruginosa PAO1, of which the pstCAB genes had been cloned previously, was also cloned (Nikata, T. et al., Mol. Gen. Genet., 250, 692-698, 1996). The predicted translation products of the P. putida pstSCAB genes showed 83, 75, 78 and 88% amino acid identity with their P. aeruginosa counterparts. Two well-conserved Pho box sequences were found in the region upstream of the pstS gene (15/18 base identity with the consensus Pho box sequence) and in the intercistronic region between the pstS and pstC genes (11/18 base identity) of P. putida PRS2000. To investigate the functions of PstSCAB, the pstSC genes were inactivated by inserting a kanamycin resistance gene cassette into the chromosome of P. putida PRS2000. The resultant mutant, designated PNT1, failed to take up 32Pi even under conditions of Pi limitation. Strain PNT1 was also constitutive for alkaline phosphatase synthesis, as well as chemotaxis toward Pi, indicating that the Pst system is involved in the negative regulation of the pho regulon in P. putida. Although overexpression of the pstSCAB genes in P. putida PRS2000 resulted in decreased cell growth, this recombinant strain could remove Pi at a rate similar to that seen with the control strain.

Evaluation of phosphate removal from water by immobilized phosphate-binding protein PstS

The phosphate (P(i))-binding protein PstS is a member of a family of periplasmic proteins that act as high-affinity receptors for active transport systems in bacteria. PstS protein purified from Pseudomonas aeruginosa was immobilized to N-hydroxysuccinimide-activated Sepharose, packed into a plastic column (5 x 70 mm), and examined for its potential ability to remove P(i) from water. The PstS-Sepharose column completely removed P(i) from 32P-labeled pond water containing about 0.5 microM P(i) (0.015 mg P per liter). More than 90% of 32P-P(i) that was retained in the column could be eluted by washing with low-pH water.

Establishment of an immortalised human ovarian surface epithelial cell line without chromosomal instability

Epithelial ovarian carcinoma is thought to derive from ovarian surface epithelium (OSE). The black box of the early molecular changes in ovarian carcinogenesis is being interpreted by the development of experimental systems employing immortalised human OSE cells. However, the existing cell lines of the OSE cells have limited utility due to chromosomal instability. Our goal was to establish new immortalised human OSE cells that retain the original characteristics of the primary cells without chromosomal alterations. Using primary human OSE cells obtained from a postmenopausal patient with endometrial cancer, five cell lines (‘HOSE1’ lines) were newly established by infection with retroviral expression vectors containing type 16 human papillomavirus (HPV-16) E6, E7, a variant E6 (E6Δ151), and Bmi1 polycomb gene, in combination with telomerase reverse transcriptase (hTERT). Consequently, five HOSE1s cell lines, HOSE1s-E6/hTERT, -E7/hTERT, -E6/E7/hTERT, -E6Δ151/E7/hTERT, and -E6Δ151/Bmi1/hTERT, grew beyond the population doubling number of 200. These cell lines, except for HOSE1-E6/hTERT, essentially showed the original features of the primary human OSE cells. Of them, HOSE1-E7/hTERT preserved diploidy in a kariotype analysis, and did not show transformed phenotypes in anchorage-independent growth and tumour formation. Thus, HOSE1-E7/hTERT may provide a novel model system with which to investigate the mechanisms of early molecular changes.

An experimental study of a new pull-through technique for aortic arch aneurysm in a porcine model

A new pull-through technique for placement of the aortic arch stent-graft was developed. Self-expandable curved stents (Matsui-Kitamura stents) were used on 4 pigs. With use of the endoscopic system, the sheath insertion was performed at the ascending aorta. By this pull-through method from the ascending aorta to the femoral artery, the stent was deployed into the aortic arch. All stents were successfully deployed into the correct position, and they fitted into the curvature of the aortic arch wall. By this method, stent-grafting for aortic arch aneurysm is expected to be performed with more accuracy and safety.

Beta-synuclein gene alterations in dementia with Lewy bodies

OBJECTIVE

To determine whether mutations in the genes for alpha-synuclein or beta-synuclein are responsible for dementia with Lewy bodies (DLB), a disorder closely related to Parkinson disease (PD).

METHODS

The authors ascertained 33 sporadic cases of DLB and 10 kindreds segregating DLB. DNA samples from the 43 index cases were screened for alterations in the genes for alpha-synuclein and beta-synuclein, as alpha-synuclein alterations cause PD and beta-synuclein may modulate alpha-synuclein aggregation and neurotoxicity.

RESULTS

Two amino acid alterations were identified in unrelated DLB index cases: a valine to methionine substitution at codon 70 (V70M) and a proline to histidine substitution at codon 123 (P123H), both in the beta-synuclein gene. These amino acid substitutions occur at conserved residues in highly conserved regions of the beta-synuclein protein. Screening of at least 660 chromosomes from control subjects matched to the patients' population groups failed to identify another V70M or P123H allele. Cosegregation analysis of an extended pedigree segregating the P123H beta-synuclein alteration suggested that it is a dominant trait with reduced penetrance or a risk factor polymorphism. Histopathology and immunohistochemistry analysis of index case brain sections revealed widespread Lewy body pathology and alpha-synuclein aggregation without evidence of beta-synuclein aggregation.

CONCLUSION

Mutations in the beta-synuclein gene may predispose to DLB.

Absorption-enhancing effect of glycyrrhizin induced in the presence of capric acid

The absorption-enhancing effect of the simultaneous administration of sodium caprate (Cap-Na) and dipotassium glycyrrhizinate (Grz-K) was investigated to clarify an effect of Grz-K. A combination of 0.1% (w/v) Cap-Na and 2% (w/v) Grz-K had a rapid and long-lasting absorption-enhancing activity in Caco-2 cell monolayers under conditions where Cap-Na and Grz-K showed a weak and no activity, respectively. The simultaneous treatment of a Caco-2 cell monolayer with Cap-Na and Grz-K showed no change in intracellular calcium ion level, although a major mechanism of absorption-enhancing effect for Cap-Na was elevation of intracellular calcium ion level. On the other hand, the simultaneous enhancing effect of Cap-Na and Grz-K was inhibited by H7, a PKC inhibitor. Possibly, Grz-K showed an absorption-enhancing effect via PKC cellular signaling pathway after penetration into cell according to increasing membrane permeability by Cap-Na. The absorption of sCT by the rat colon was enhanced by a combination of 0.1% (w/v) Cap-Na and 2% (w/v) Grz-K, and its effect continued even 9h after the onset of the experiment. Furthermore, the simultaneous treatment of 0.1% (w/v) Cap-Na and 2% (w/v) Grz-K showed a negligible histological changes to the colon mucosal membrane and a negligible toxicity on Caco-2 cell monolayer. A combination of Cap-Na and Grz-K shows a synergistic absorption-enhancing effect with little mucosal injury, which is applicable to colon-specific delivery.

Acinic Cell Carcinoma of the Trachea: Report of a Case

Acinic cell carcinoma (ACC) is a very rare primary tracheal carcinoma. We report a case of primary ACC of the trachea, which represents, to the best of our knowledge, only the fifth such case ever documented. Pharyngolaryngoesophagectomy was necessary for complete resection because the tumor invaded the trachea widely, up to the cricoid cartilage and involving the cervical esophagus. Although invasion of the upper aerodigestive tract by neoplasma is rare, to achieve complete resection and an acceptable prognosis, even a tumor with low malignancy requires wide resection.

Adult-onset leukoencephalopathy with vanishing white matter with a missense mutation inEIF2B5

We report of a woman aged 52 years born to consanguineous parents and seeking treatment for progressive dementia and delusion. Neurologic examination revealed dementia and emotional instability, indifference, and confabulation. There was also mild spasticity of the bilateral lower limbs. MRI revealed diffuse white matter hyperintensity on T2-weighted images accompanied by hypointense areas on fluid-attenuated inversion recovery images. A homozygous missense mutation was identified in EIF2B5.

Simultaneous monitoring of somatosensory evoked potentials and regional cerebral oxygen saturation combined with serial measurement of plasma levels of cerebral specific proteins for the early diagnosis of postoperative brain damage in cardiovascular surgery

Combined somatosensory evoked potential (SEP) and regional brain oxygen saturation (rSO(2)) monitoring and simultaneous measurement of plasma levels of S100Beta and creatine kinase-isozyme BB (CK-BB) were performed to evaluate how reliable these diagnostic modality complexes are in the early prediction of neurological complications after surgery. Between 1999 and 2002, intraoperative SEP and rSO(2) monitoring combined with measurements of S100Beta and CK-BB levels in blood were performed in 82 consecutive patients undergoing cardiovascular operations with cardiopulmonary bypass (CPB). Twelve (14.6%) of these patients were diagnosed as having neurological complications after surgery; seven with transient neurological dysfunction (8.5%), and five with permanent stroke (6.1%). Twenty one of 82 patients in whom rSO(2) was recorded were judged abnormal; however, only nine of the 21 (42.9%) were diagnosed as having brain damage - diagnostic sensitivity and specificity being 75.0% and 82.9%, respectively. All six patients who showed abnormal SEP during surgery had neurological complications, but normal SEP was recorded in six other patients with apparent evidence of neurological complications - diagnostic sensitivity and specificity being 50% and 100%, respectively. There were no significant differences in S100Beta levels between patients with and without brain complications at 1 h and 24 h after CPB, but significant differences were detected in CK-BB levels at 24 h after CPB. In conclusion, simultaneous abnormalities detected in SEP and rSO(2) are highly predictive of cerebral neurocirculatory disturbances, but they are not so sensitive in diagnosing restricted focal cerebral lesions. Additional determinations of blood CK-BB levels might be valuable only to confirm the newly established brain complications.