Raman spectra of graphene ribbons

Raman spectra of graphene nanoribbons with zigzag and armchair edges are calculated within non-resonant Raman theory. Depending on the edge structure and polarization direction of the incident and scattered photon beam relative to the edge direction, a symmetry selection rule for the phonon type appears. These Raman selection rules will be useful for the identification of the edge structure of graphene nanoribbons.

Clinicopathological and therapeutic significance of CXCL12 expression in lung cancer

Interactions between CXCL12 and its receptors CXCR4 or CXCR7 are involved in tumor growth and metastasis in various types of human cancer. However, CXCL12 expression and its role in lung cancer are not fully elucidated. Here we examined the expression of CXCL12 in 54 lung cancer cell lines consisting of 23 small cell lung cancers (SCLCs) and 31 non-small cell lung cancers (NSCLCs). CXCL12 was overexpressed in lung cancer cell lines compared to non-malignant human bronchial epithelial cell lines (N = 6). CXCL12 expression was positively but weakly correlated with the expression of CXCR4 or CXCR7. We also examined CXCL12 expression in 89 NSCLC specimens and found that CXCL12 expression was significantly higher in tumor specimens from female patients, non-smokers and adenocarcinoma patients. Small interfering RNAs targeting CXCL12 inhibited cellular proliferation, colony formation and migration of CXCL12-overexpressing lung cancer cells; however, this inhibition did not occur in lung cancer cells that lacked CXCL12. Furthermore, the anti-CXCL12 neutralizing antibody mediated inhibitory effects in three lung cancer cell lines that overexpressed CXCL12, but not in two CXCL12 non-expressing lung cancer cell lines nor two non-malignant bronchial epithelial cell lines. The present study demonstrates that: CXCL12 is concomitantly overexpressed with CXCR4 or CXCR7 in lung cancers; CXCL12 is highly expressed in NSCLCs from females, non-smokers and adenocarcinoma patients; and disruption of CXCL12 inhibits the growth and migration of lung cancer cells. Our findings indicate that CXCL12 is required for tumor growth and provide a rationale for the anti-CXCL12 treatment strategy in lung cancer.

Thrombin-cleaved osteopontin is increased in urine of patients with rheumatoid arthritis

OBJECTIVE

To measure concentrations of the thrombin-cleaved isoform of osteopontin (OPN) in urine and plasma of patients with rheumatoid arthritis (RA), and to assess whether levels of thrombin-cleaved OPN are associated with measures of RA.

METHODS

Subjects comprised 70 patients with RA, 20 patients with osteoarthritis (OA), and 46 healthy controls. RA disease activity was evaluated by tender joint count, swollen joint count, patient's global assessment of disease activity, erythrocyte sedimentation rate (ESR), and levels of C-reactive protein (CRP), matrix metalloproteinase-3 (MMP-3), and rheumatoid factor (RF), as well as 28-joint count Disease Activity Score (DAS28). OPN levels in plasma and urine were measured by ELISA.

RESULTS

Median levels of thrombin-cleaved OPN in urine (U-half) were significantly higher in RA patients (143.5 pmol/mmol Cr) than in healthy controls (67.9 pmol/mmol Cr) or OA patients (69.8 pmol/mmol Cr). Thrombin-cleaved OPN was not detected in plasma. U-half levels correlated significantly with levels of CRP (r = 0.26, p = 0.03), ESR (r = 0.26, p = 0.03), and RF (r = 0.28, p = 0.03). Median U-half levels were significantly higher in patients with stage III (249.9 pmol/mmol Cr) and IV (251.6 pmol/mmol Cr) disease than in patients with stage I (98.6 pmol/mmol Cr) disease.

CONCLUSION

Our results suggest that urine levels of the thrombin-cleaved isoform of OPN may reflect the severity of active inflammatory arthritis in patients with RA.

Diameter dependence of the dielectric constant for the excitonic transition energy of single-wall carbon nanotubes

The measured optical transition energies Eii of single-wall carbon nanotubes are compared with bright exciton energy calculations. The Eii differences between experiment and theory are minimized by considering a diameter-dependent dielectric constant kappa, which comprises the screening from the tube and from the environment. Different kappa dependencies are obtained for (E11(S), E22(S), E11(M)) relative to (E33(S), E44(S)). A changing environment changes the kappa diameter dependence for (E11(S), E22(S), E11(M)), but for (E33(S), E44(S)) the environmental effects are minimal. The resulting calculated exciton energies reproduce experimental E_{ii} values within +/-70 meV for a diameter range (0.7<d(t)<3.8 nm) and 1.2<Eii<2.7 eV, thus providing a theoretical justification for Eii, environmental effects and important insights on the dielectric screening in one-dimensional structures.

Softening of the radial breathing mode in metallic carbon nanotubes

The softening of the radial breathing mode (RBM) of metallic single walled carbon nanotubes (m-SWNTs) due to electron-phonon coupling has been studied by observing the Fermi level [see text] dependence of the RBM Raman peak. In situ Raman spectra were obtained from several individual m-SWNTs while varying [see text] electrochemically. The RBM frequency of an intrinsic m-SWNT is shown to be down-shifted relative to highly doped tubes by approximately 2 cm(1). The down-shift is greatest for small diameter and small chiral angle SWNTs. Most tubes show no change in RBM linewidth. A comparison is drawn between the RBM and the G band (A(LO) phonon) with respect to the [see text] dependence of their frequencies and linewidths.

Influenza virus infections in Lebanese children in the 2007-2008 season

We conducted the first epidemiological study of influenza in Lebanon, a temperate country in the Middle East. Between January to May 2008, 39 patients with influenza-like illness were tested. Of these, 51% contracted influenza in January alone, while no influenza cases were detected in May. Among the 39 patients, 11 influenza A and 4 influenza B cases were detected by rapid kit in addition to 10 respiratory syncytial virus cases by real-time PCR. The influenza viruses were genetically divergent from the 2007/2008 season's vaccine strains, but resembled strains circulating in other countries during the same season.

IL23 differentially regulates the Th1/Th17 balance in ulcerative colitis and Crohn's disease

BACKGROUND

A novel T helper (Th) cell lineage, Th17, that exclusively produces the proinflammatory cytokine interleukin 17 (IL17) has been reported to play important roles in various inflammatory diseases. IL23 is also focused upon for its potential to promote Th17. Here, the roles of the IL23/IL17 axis in inflammatory bowel diseases such as ulcerative colitis (UC) and Crohn's disease (CD) were investigated.

METHODS

Mucosal samples were obtained from surgically resected specimens (controls, n = 12; UC, n = 17; CD, n = 22). IL17 production by isolated peripheral blood (PB) and lamina propria (LP) CD4(+) cells was examined. Quantitative PCR amplification was performed to determine the mRNA expression levels of IL17, interferon gamma (IFNgamma), IL23 receptor (IL23R) and retinoic acid-related orphan receptor gamma (RORC) in LP CD4(+) cells, and IL12 family members, such as IL12p40, IL12p35 and IL23p19, in whole mucosal specimens. The effects of exogenous IL23 on IL17 production by LP CD4(+) cells were also examined.

RESULTS

IL17 production was higher in LP CD4(+) cells than in PB. Significant IL17 mRNA upregulation in LP CD4(+) cells was found in UC, while IFNgamma was increased in CD. IL23R and RORC were upregulated in LP CD4(+) cells isolated from both UC and CD. IL17 production was significantly increased by IL23 in LP CD4(+) cells from UC but not CD. Upregulated IL23p19 mRNA expression was correlated with IL17 in UC and IFNgamma in CD.

CONCLUSIONS

IL23 may play important roles in controlling the differential Th1/Th17 balance in both UC and CD, although Th17 cells may exist in both diseases.

Resonant Raman scattering of the smallest single-walled carbon nanotubes

We report optical properties of the smallest single-walled carbon nanotubes (SWNTs) with a diameter of only 3 A. These ultrasmall SWNTs are fabricated in the elliptical nanochannels of an AlPO-11 (AEL) single crystal. Polarized and resonant Raman scattering unambiguously revealed that these 0.3 nm SWNTs are of (2,2) armchair symmetry. Interestingly, the (2,2) armchair tube has two metastable ground states corresponding to two slightly different lattice constants in the axial direction: one state is metallic and the other is semiconducting.

Histopathological evidence of small-vessel vasculitis within the skin and lungs associated with interstitial pneumonia in an adult patient with dermatomyositis

Dermatomyositis (DM) often has a poor prognosis, due to complications associated with malignancy or interstitial pneumonia (IP). It is uncommon to find histopathological small-vessel vasculitis within cutaneous lesions and pulmonary capillaritis in patients with DM. A 64-year-old woman was diagnosed with DM based on the presence of quadriparesis, typical heliotropic rash, Gottron's papules, increased serum levels of muscle enzymes and typical muscle biopsy findings. She also had associated IP, which subsequently developed into a rapidly progressive condition. We found a high titre of Krebs von den Lunge (KL)-6 in her serum. Measurement of serum KL-6 level is widely accepted as a diagnostic test to monitor the activity of interstitial lung diseases. Histopathological examinations of the cutaneous and lung-associated features showed small-vessel vasculitis. We suggest that investigation of KL-6 levels in patients with DM and associated conditions should be carried out to determine if raised KL-6 levels are useful at predicting outcome or severity of various features.

Clinical epidemiology of ciprofloxacin-resistant Proteus mirabilis isolated from urine samples of hospitalised patients

This study investigated the clinical characteristics of ciprofloxacin-resistant Proteus mirabilis isolates from urine samples associated with nosocomial infection or colonisation, and identified the risk-factors for ciprofloxacin resistance. Data for patients with ciprofloxacin-resistant P. mirabilis isolates (n=13) were compared with those for randomly selected patients with ciprofloxacin-susceptible P. mirabilis isolates (n=40) who were matched by temporal occurrence as control patients. The majority of ciprofloxacin-resistant P. mirabilis isolates were multiresistant, and ciprofloxacin resistance was associated significantly with previous use of fluoroquinolones and production of extended-spectrum beta-lactamases.

Direct electrical power generation from urine, wastes and biomass with simultaneous photodecomposition and cleaning

Electric power was for the first time generated directly from urine, wastes, and biomass with simultaneous photodecomposition and cleaning by using a biophotofuel cell (BPFC) composed of a nanoporous TiO2 film semiconductor photoanode and an O2-reducing cathode. Human urine exhibited a PFC characteristics with J(sc) 0.086 mA cm(-2), Voc 0.56 V, and fill factor (FF) 0.50 under irradiation by a solar simulator with AM 1.5 G and 100 mW cm(-2) incident light intensity. Both the soluble and residual parts of waste paper partially solubilized by a H3PO4 aqueous solution were also photodecomposed with simultaneous electrical power generation. As trials of various biomass materials, Coca-Cola (to test colored sample), Japanese rice wine (to test alcohol aqueous solution), and grated radish (to test slurry state sample) also generated effectively electrical power during photodecomposition by a solar simulator.

Estimation of pulmonary oxygen consumption in the early postoperative period after thoracic surgery

Lung injury, including pneumonia, can occur in the early postoperative period following thoracic surgery. Pulmonary oxygen consumption is thought to increase in patients with pulmonary infection. This study measured oxygen consumption in relationship to lung injury in the early postoperative period after thoracic surgery. Thirty-five patients who underwent thoraco-abdominal oesophagectomy for oesophageal cancer were studied. Measured oxygen-consumption was obtained by indirect calorimetry and calculated oxygen-consumption was simultaneously determined by the reverse Fick method. The difference in oxygen consumption was attributed to pulmonary oxygen consumption. The difference in oxygen consumption increased to 23.1 ml.min(-1).m(-2) on postoperative day 2. In patients with pneumonia the difference in oxygen consumption increased significantly to 39.0 ml.min(-1).m(-2) the day before clinical onset of pneumonia, and it increased further to 65.7 ml.min(-1).m(-2) on the day that pneumonia became clinically apparent. These findings suggest that the difference in oxygen consumption may be useful for estimating the extent of lung injury and for predicting pulmonary complications in the postoperative period.

HLA-B52-positive vasculo-Behçet disease: usefulness of magnetic resonance angiography, ultrasound study, and computed tomographic angiography for the early evaluation of multiarterial lesions

We report a case of HLA-B52-positive Behçet disease accompanied by multiarterial lesions. A 24-year-old woman was suffering from sporadic high fever and recurrent oral and genital ulcers, and laboratory data revealed severe inflammation. A diagnosis of Behçet disease was made. Magnetic resonance angiography, ultrasound study, and computed tomographic angiography demonstrated multiarterial lesions that had caused no symptoms. These noninvasive examinations were extremely useful in evaluating asymptomatic early vascular lesions.

Pitavastatin ameliorates albuminuria and renal mesangial expansion by downregulating NOX4 in db/db mice

Recent studies have uncovered various pleiotrophic effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase-inhibiting drugs (statins). Several studies have identified a beneficial effect of statins on diabetic nephropathy; however, the molecular mechanisms are unclear. In this study, we show that statin ameliorates nephropathy in db/db mice, a rodent model of type 2 diabetes, via downregulation of NAD(P)H oxidase NOX4, which is a major source of oxidative stress in the kidney. Pitavastatin treatment for 2 weeks starting at 12 weeks of age significantly reduced albuminuria in the db/db mice concomitant with a reduction of urinary 8-hydroxy-2'-deoxyguanosine and 8-epi-prostaglandin F(2alpha). Immunohistochemical analysis found increased amounts of 8-hydroxy-2'-deoxyguanosine and NOX4 protein in the kidney of db/db mice. Quantitative reverse transcription-polymerase chain reaction also showed increased levels of NOX4 mRNA. Pitavastatin normalized all of these changes in the kidneys of diabetic animals. Additionally, 12-week treatment with the statin completely normalized the levels of transforming growth factor-beta1 and fibronectin mRNA as well as the mesangial expansion characteristic of diabetic nephropathy. Our study demonstrates that pitavastatin ameliorates diabetic nephropathy in db/db mice by minimizing oxidative stress by downregulating NOX4 expression. These findings may provide insight into the mechanisms of statin therapy in early stages of diabetic nephropathy.

Sound spectrogram analysis in patients receiving Kawahara's surgical voice restoration for advanced carcinoma of the hypopharynx and cervical esophagus

Loss of voice after total laryngectomy is a major concern that has prompted much effort to develop methods of surgical voice restoration. In 1992, Kawahara described a tracheocolic shunt for voice restoration using a revascularized ileocolic graft. With this method, aspiration through the phonatory shunt is prevented by the ileocolic valve (Bauhin's valve), while vocalization is allowed. The purpose of this study was to use sound spectrogram analysis to evaluate voices surgically restored in that way. Between 2002 and 2005, 10 consecutive patients underwent laryngopharyngoesophagectomy with Kawahara's surgical voice restoration for advanced carcinoma of the hypopharynx and/or cervical esophagus at Akita University Hospital, Japan. We then used sound spectrography to analyze and compare the voices of patients receiving Kawahara's voice restoration, against healthy volunteers and patients who underwent the same surgery without voice restoration and spoke using an electronic larynx. We also evaluated the intelligibility of conversation and performed a listening test. The sound spectrograms showed that when produced by the electronic larynx, consonant sounds and voice frequencies below 300 Hz were not clearly recognized. By contrast, in patients who received Kawahara's surgical voice restoration, consonant and vowel sounds at frequencies above and below 300 Hz were clearly recognized. Although conversation was intelligible with both Kawahara's surgical voice restoration and the electronic device, listeners judged the voice produced by the former to be superior. Thus, the voice produced by Kawahara's surgical voice restoration is superior to that produced by the electronic larynx.

Studying disorder in graphite-based systems by Raman spectroscopy

Raman spectroscopy has historically played an important role in the structural characterization of graphitic materials, in particular providing valuable information about defects, stacking of the graphene layers and the finite sizes of the crystallites parallel and perpendicular to the hexagonal axis. Here we review the defect-induced Raman spectra of graphitic materials from both experimental and theoretical standpoints and we present recent Raman results on nanographites and graphenes. The disorder-induced D and D' Raman features, as well as the G'-band (the overtone of the D-band which is always observed in defect-free samples), are discussed in terms of the double-resonance (DR) Raman process, involving phonons within the interior of the 1st Brillouin zone of graphite and defects. In this review, experimental results for the D, D' and G' bands obtained with different laser lines, and in samples with different crystallite sizes and different types of defects are presented and discussed. We also present recent advances that made possible the development of Raman scattering as a tool for very accurate structural analysis of nano-graphite, with the establishment of an empirical formula for the in- and out-of-plane crystalline size and even fancier Raman-based information, such as for the atomic structure at graphite edges, and the identification of single versus multi-graphene layers. Once established, this knowledge provides a powerful machinery to understand newer forms of sp(2) carbon materials, such as the recently developed pitch-based graphitic foams. Results for the calculated Raman intensity of the disorder-induced D-band in graphitic materials as a function of both the excitation laser energy (E(laser)) and the in-plane size (L(a)) of nano-graphites are presented and compared with experimental results. The status of this research area is assessed, and opportunities for future work are identified.

Modulation of scratching behavior by silencing an endogenous cyclooxygenase-1 gene in the skin through the administration of siRNA

BACKGROUND

RNA interference (RNAi) is rapidly becoming a major tool that is revolutionizing research in the bioscience and biomedical fields. To apply the RNAi technique in vivo, it is crucial to develop appropriate methods of guiding the short interfering RNA (siRNA) molecules to the right tissues and cells. Here, we demonstrate an efficient method for performing gene knockdown in the body skin using the in vivo electro-transduction of siRNA. Using this method, we examined whether the targeted silencing of the cyclooxygenase (COX) gene in the skin could modulate the scratching behavior of an atopic dermatitis mouse model.

METHODS

NC/Nga mice were used as the atopic dermatitis model. Using our optimized in vivo electroporation conditions, siRNAs were introduced into the skin; the silencing efficiency was then analyzed by Western blotting, measuring the levels of prostaglandins, and immunohistochemistry. The scratching behaviors of the mice were measured using an automatic system.

RESULTS

Targeted silencing of the COX-1 gene using our in vivo siRNA technique significantly accelerated the scratching behavior of NC/Nga mice, whereas the COX-2 siRNA showed no effect. In addition, the effect of COX-1 siRNA was mimicked by treatment with a COX-1-selective inhibitor (SC-560).

CONCLUSIONS

We have demonstrated the successful silencing of endogenous gene expression in the skin using the intradermal transfection of unmodified siRNA via electroporation. Using this method, we revealed that COX- 1-mediated prostaglandins may act as endogenous inhibitors of scratching behavior.

[Two cases of intractable hepatic hydrothorax successfully treated with nasal CPAP]

Hepatic hydrothorax is often resistant to various treatments. A failure in the treatment for hepatic hydrothorax may be associated with poor prognosis. We report two cases of intractable hepatic hydrothorax successfully treated by combining chemical pleurodesis using OK-432 with nasal continuous positive airway pressure. Combination therapy may provide a minimally invasive and effective treatment for intractable hepatic hydrothorax.

Amino acid substitutions in malate dehydrogenases of piezophilic bacteria isolated from intestinal contents of deep-sea fishes retrieved from the abyssal zone

To examine the occurrence in other deep-sea bacteria of two amino acid substitutions (Ala-180 and His-229) in malate dehydrogenase (MDH) found previously in the deep-sea piezophilic Moritella sp. strain 2D2, we cloned and sequenced MDH genes of deep-sea piezophilic Moritella and Shewanella strains isolated from intestinal contents of deep-sea fishes, as well as other Moritella species from deep-sea water and sediments: M. marina, M. japonica, and M. yayanosii. The piezophilic Moritella strains had a Val residue or an Ala residue at position 180 and all the Moritella strains except for one had a His residue at position 229. However, four piezophilic-strain-specific substitutions at positions 103, 111, 229, and 283 were found to be completely conserved in the MDH of the intestinal Moritella strains of deep-sea fishes, indicating the substitutions may be habitat-specific. The piezophilic Shewanella strains had a Val residue and a Gln residue at positions 180 and 229, respectively. However, the MDHs of the Shewanella strains had five piezophilic-strain-specific substitutions at positions 61, 65, 107, 161, and 202. Therefore, the enzymatic strategies for responding to deep-sea high pressure environments of the MDHs between the genera Moritella and Shewanella are potentially different. Moreover, homology modeling shows these substitutions found in the MDHs of both genera except for position 229 in the subunit interface are located on the exposed region of the MDH molecules, indicating the substitutions may be related to the hydration state of the molecules.

Strain-induced interference effects on the resonance Raman cross section of carbon nanotubes

In this Letter, we report the effects of strain on the electronic properties of single-wall carbon nanotubes. When we normalize the electronic transition energies to the corresponding values obtained for unstrained tubes, we obtain that, regardless of the tube diameter, all the data collapse onto universal curves following an n - m = constant family pattern. In the case of metallic tubes, quantum interference effects on the Raman cross section are predicted for strained tubes when the energies of the lower and the upper components have nearly the same values. Experimental evidence for the strain-induced Raman cross section changes is observed in single nanotube spectroscopy.

Infrared-active vibrational modes of single-walled carbon nanotubes

The IR-active vibrational modes of single-walled carbon nanotubes have been observed by optical transmission through thin films of bundled nanotubes. Because IR-active chemical functional groups, e.g., -COOH, -OH, might be attached to the tube walls and contribute additional spectral features, we have also studied the effects of chemical purification and long-term high-temperature vacuum annealing on the IR spectrum. Through comparison with theory, we are able to assign much of the sharp structure observed in our IR spectra.

Phonon-assisted excitonic recombination channels observed in DNA-wrapped carbon nanotubes using photoluminescence spectroscopy

By using a sample of DNA-wrapped single-wall carbon nanotubes strongly enriched in the (6,5) nanotube, photoluminescence emissions observed at special excitation energy values were identified with specific mechanisms of phonon-assisted excitonic absorption and recombination processes associated with (6,5) nanotubes, including one-phonon, two-phonon, and some continuous-luminescence processes. Such detailed processes are not separately identified in three-dimensional semiconducting materials. A general theoretical framework is presented to interpret the experimentally observed phonon-assisted processes in terms of excitonic states.

Allelic losses on chromosome 3p are accumulated in relation to morphological changes of lung adenocarcinoma

We performed allelotyping analysis at nine regions on chromosome 3p using 56 microdissected samples from 23 primary lung adenocarcinomas to examine the process of progression within individual lung adenocarcinoma with various grades of differentiation. Identical allelic patterns among various grades of differentiation were found in eight cases. Accumulation of allelic losses from high to lower differentiated portions was found in seven cases and accumulation of allelic losses from low to higher differentiated portions was found in five cases. Various allelic patterns among various grades of differentiation were found in three cases. These results suggested that allelic losses on 3p play an important role in morphological changes of lung adenocarcinomas. We also investigated the relationship between allelic losses on 3p and histological subtypes of lung adenocarcinoma. The frequencies of allelic losses at 3p14.2 and telomeric region of 3p21.3 were higher in papillary type tumour (nine out of 14, 64% and 11 out of 15, 73%) than in bronchioloalveolar carcinoma-type tumour (one out of 8, 13%; P=0.031 and four out of 12, 33%; P = 0.057). These results indicated that allelic losses at 3p14.2 and telomeric region of 3p21.3 are related to pattern of the proliferation of lung adenocarcinoma.

Determination of nanotubes properties by Raman spectroscopy

The basic concepts and characteristics of Raman spectra from single-wall carbon nanotubes (SWNTs, both isolated and bundled) are presented. The physical properties of the SWNTs are introduced, followed by the conceptual framework and characteristics of their Raman spectra. Each Raman feature, namely the radial breathing mode, the tangential G band, combination modes and disorder-induced bands are discussed, addressing their physical origin, as well as their capability for characterizing SWNT properties.

One-dimensional character of combination modes in the resonance Raman scattering of carbon nanotubes

Resonance Raman spectroscopy with an energy tunable system is used to analyze the 600-1100 cm(-1) spectral region in single-wall carbon nanotubes. Sharp peaks are associated with the combination of zone folded optic and acoustic branches from 2D graphite. These combination modes exhibit a peculiar dependence on the excitation laser energy that is explained on the basis of a highly selective resonance process that considers phonons and electrons in low dimensional materials.

Anisotropy of the Raman spectra of nanographite ribbons

A polarized Raman study of nanographite ribbons on a highly oriented pyrolytic graphite substrate is reported. The Raman peak of the nanographite ribbons exhibits an intensity dependence on the light polarization direction relative to the nanographite ribbon axis. This result is due to the quantum confinement of the electrons in the 1D band structure of the nanographite ribbons, combined with the anisotropy of the light absorption in 2D graphite, in agreement with theoretical predictions.

Differences in malate dehydrogenases from the obligately piezophilic deep-sea bacteriumMoritellasp. strain 2D2 and the psychrophilic bacteriumMoritellasp. strain 5710

The gene encoding malate dehydrogenase (MDH) of the obligately piezophilic deep-sea bacterium Moritella sp. strain 2D2 was cloned and sequenced. There were two positions [close to the active site (Ala-180) and in the subunit interaction site (His-229)] with 2D2-specific substitutions. The MDH genes of strain 2D2 and a psychrophilic bacterium Moritella sp. strain 5710 exhibiting the highest sequence similarity were overexpressed in Escherichia coli. The 2D2 MDH was more heat-stable than the 5710 MDH. The apparent Km value at 62.1 MPa for NADH of the 2D2 MDH was higher than that of the 5710 MDH. The 2D2 MDH in which a His-Gln substitution was introduced at position 229 decreased the thermal stability and Km value at 62.1 MPa. The 5710 MDH that was substituted Gln-229 with His increased the thermal stability and Km value at 62.1 MPa. These results indicate that the His residue at position 229 of the 2D2 MDH may play a role in the thermal stability and the MDH function at high pressure.

[Microorganism "Montezuma" of the order Rickettsiales: the potential causative agent of tick-borne disease in the Far East of Russia]

A new microorganism, tentatively named "Montezuma" was detected in ticks and in specimens (blood, bioptic specimens of the primary affect) taken from patients with an acute fever disease, etiologically linked with the bites of Ixodes ticks in the Far East of the Russian Federation. After sequencing the products of the amplification of DNA isolated from ticks with wide-spectrum primers new primers were developed, highly specific to the unusual sequence thus obtained. The study revealed that ticks of the species Ixodes persulcatus (97%) and Haemophysalis concinnae (5%) contained DNA of this microorganism. The same DNA was detected in materials taken from the patients. The phylogenetic analysis of the gene showed that this organism formed an independent and well defined branch within the order Rickettsiales. The nearest homology (89%) was observed with recently detected endosymbiotes Acanthamoeba. The similarity with their relatives from the families Rickettsiaceae and Anaplasmataceae of the order Rickettsiales was within 81-86%, which made it possible to infer the existence of, probably, only a new genus, but also a family. The isolated DNA belonged, supposedly, to the new microoganism which caused a tick-borne disease in humans, transmitted through bites of Ixodes ticks, and was, supposedly, widely spread in the southern area of the Khabarovsk Territory.

The concept of cutting lines in carbon nanotube science

A review is presented of one-dimensional cutting lines that are utilized to obtain the physical properties of carbon nanotubes from the corresponding properties of graphite by the zone-folding scheme. Quantization effects in general low-dimensional systems are briefly discussed, followed by a more detailed consideration of one-dimensional single-wall carbon nanotubes. The geometrical structure of the nanotube is described, from which quantum confined states are constructed. These allowed states in the momentum space of graphite are known as cutting lines. Different representations of the cutting lines in momentum space are introduced. Electronic and phonon dispersion relations for nanotubes are derived by using cutting lines and the zone-folding scheme. The relation between cutting lines and singularities in the electronic density of states is considered. The selection rules for carbon nanotubes are shown to be directly connected with the cutting lines. Different experimental techniques are considered that confirm the validity of cutting lines and the zone-folding approach.

Differential prevalence of HIV type 1 subtype B and CRF01_AE among different sexual transmission groups in Tokyo, Japan, as revealed by subtype-specific PCR

We determined the subtype of HIV-1 in 89 infected individuals attending three reference hospitals located in the Tokyo metropolitan area of Japan. Subtyping was performed with subtype-specific polymerase chain re-action (PCR) distinguishing subtype A, B, C, and CRF01_AE and/or phylogenetic analysis of HIV-1 env C2V3C3 sequences. Subtype-specific PCR provided unequivocal results in 97% of samples. Sixty-five subjects were infected with subtype B, 16 with CRFO1_AE, 4 with subtype A, 1 with CRF02_AG, and 3 with subtype C. Among 31 Japanese individuals infected through heterosexual contact, 13 were infected with subtype Band 12 with CRFO1_AE. All of the 41 Japanese men infected through homosexual contact harbored subtype B. These results indicate that subtype B is exclusively predominant in a homosexually transmitted group, whereas subtype B and CRFO1_AE are evenly predominant in a heterosexually transmitted group.

A case of fetal subdural hematoma at 31 weeks of gestation in a woman on warfarin therapy after Cabrol's operation

The case of a complicated pregnancy of a woman who had undergone Cabrol's operation, and whose baby suffered from subdural hematoma is presented. Although the outcome of this case was not so severe, we would like to inform about the risk to both the mother and her fetus as a result of serious complications.