Controlling crystal cleavage in focused ion beam shaped specimens for surface spectroscopy

Our understanding of quantum materials is commonly based on precise determinations of their electronic spectrum by spectroscopic means, most notably angle-resolved photoemission spectroscopy (ARPES) and scanning tunneling microscopy. Both require atomically clean and flat crystal surfaces, which are traditionally prepared by in situ mechanical cleaving in ultrahigh vacuum chambers. We present a new approach that addresses three main issues of the current state-of-the-art methods: (1) Cleaving is a highly stochastic and, thus, inefficient process; (2) fracture processes are governed by the bonds in a bulk crystal, and many materials and surfaces simply do not cleave; and (3) the location of the cleave is random, preventing data collection at specified regions of interest. Our new workflow is based on focused ion beam machining of micro-strain lenses, in which shape (rather than crystalline) anisotropy dictates the plane of cleavage, which can be placed at a specific target layer. As proof-of-principle, we show ARPES results from micro-cleaves of Sr2RuO4 along the ac plane and from two surface orientations of SrTiO3, a notoriously difficult to cleave cubic perovskite.

Anomalous electrons in a metallic kagome ferromagnet

Ordinary metals contain electron liquids within well-defined 'Fermi' surfaces at which the electrons behave as if they were non-interacting. In the absence of transitions to entirely new phases such as insulators or superconductors, interactions between electrons induce scattering that is quadratic in the deviation of the binding energy from the Fermi level. A long-standing puzzle is that certain materials do not fit this 'Fermi liquid' description. A common feature is strong interactions between electrons relative to their kinetic energies. One route to this regime is special lattices to reduce the electron kinetic energies. Twisted bilayer graphene1-4 is an example, and trihexagonal tiling lattices (triangular 'kagome'), with all corner sites removed on a 2 × 2 superlattice, can also host narrow electron bands5 for which interaction effects would be enhanced. Here we describe spectroscopy revealing non-Fermi-liquid behaviour for the ferromagnetic kagome metal Fe3Sn2 (ref. 6). We discover three C3-symmetric electron pockets at the Brillouin zone centre, two of which are expected from density functional theory. The third and most sharply defined band emerges at low temperatures and binding energies by means of fractionalization of one of the other two, most likely on the account of enhanced electron-electron interactions owing to a flat band predicted to lie just above the Fermi level. Our discovery opens the topic of how such many-body physics involving flat bands7,8 could differ depending on whether they arise from lattice geometry or from strongly localized atomic orbitals9,10.

Fate of Quasiparticles at High Temperature in the Correlated Metal Sr_{2}RuO_{4}

We study the temperature evolution of quasiparticles in the correlated metal Sr_{2}RuO_{4}. Our angle resolved photoemission data show that quasiparticles persist up to temperatures above 200 K, far beyond the Fermi liquid regime. Extracting the quasiparticle self-energy, we demonstrate that the quasiparticle residue Z increases with increasing temperature. Quasiparticles eventually disappear on approaching the bad metal state of Sr_{2}RuO_{4} not by losing weight but via excessive broadening from super-Planckian scattering. We further show that the Fermi surface of Sr_{2}RuO_{4}-defined as the loci where the spectral function peaks-deflates with increasing temperature. These findings are in semiquantitative agreement with dynamical mean field theory calculations.

Flat Γ Moiré Bands in Twisted Bilayer WSe_{2}

The recent observation of correlated phases in transition metal dichalcogenide moiré systems at integer and fractional filling promises new insight into metal-insulator transitions and the unusual states of matter that can emerge near such transitions. Here, we combine real- and momentum-space mapping techniques to study moiré superlattice effects in 57.4° twisted WSe_{2} (tWSe_{2}). Our data reveal a split-off flat band that derives from the monolayer Γ states. Using advanced data analysis, we directly quantify the moiré potential from our data. We further demonstrate that the global valence band maximum in tWSe_{2} is close in energy to this flat band but derives from the monolayer K states which show weaker superlattice effects. These results constrain theoretical models and open the perspective that Γ-valley flat bands might be involved in the correlated physics of twisted WSe_{2}.

Electronic Structure of Few-Layer Black Phosphorus from μ-ARPES

Black phosphorus (BP) stands out among two-dimensional (2D) semiconductors because of its high mobility and thickness dependent direct band gap. However, the quasiparticle band structure of ultrathin BP has remained inaccessible to experiment thus far. Here we use a recently developed laser-based microfocus angle resolved photoemission (μ-ARPES) system to establish the electronic structure of 2-9 layer BP from experiment. Our measurements unveil ladders of anisotropic, quantized subbands at energies that deviate from the scaling observed in conventional semiconductor quantum wells. We quantify the anisotropy of the effective masses and determine universal tight-binding parameters, which provide an accurate description of the electronic structure for all thicknesses.

Trends of International Electives in Medical Education Undergraduates in Japan

Increasing numbers of medical students participate in international electives. However, this recent trend has yet to be examined in non-Western high-income countries such as Japan. The aim of this study is to assess recent trends in Japan, and to suggest ways in which those trends might be influenced. A retrospective cross-sectional analysis of responses to an 8-item questionnaire sent in August 2019 to 82 medical schools in Japan is reported. The responses were received in September 2019. Narrative responses were obtained regarding rationales for exchange programs, participant feedback, and challenges encountered. Responses were translated into English and categorized into themes. Of 82 Japanese medical schools, 56 (68%) responded to the questionnaire. Both the number of incoming and outgoing exchange students had increased steadily over the preceding 3-year period. The leading destinations for Japanese students were the United States (30%), other Asian (36%), and European countries (24%). Narrative responses reveal different rationales from those reported by medical schools in Western high-income countries. Only a few Japanese students chose low or middle-income countries as their destinations, as opposed to the trend seen in Western high-income countries. The reported challenges encountered by the exchange programs may provide insights for improvement. Exchanges have been greatly affected by the coronavirus disease 2019 pandemic. The results can serve as pre-pandemic baseline data and should promote further international collaboration for medical education under current circumstances.

Impact of Diabetes and KL-6 on COVID-19 Severity; A Single Center Study from Japan

AIMS/INTRODUCTION

Diabetes mellitus is reported as a risk factor for increased COVID-19 severity and mortality, but there have been few reports from Japan. Associations between diabetes mellitus and COVID-19 severity and mortality were investigated in a single Japanese hospital.

MATERIALS AND METHODS

Patients ≥20 years of age admitted to Osaka City General Hospital for COVID-19 treatment between April, 2020 and March, 2021 were included in this retrospective, observational study. Multivariable logistic regression analysis was performed to examine whether diabetes mellitus contributes to COVID-19-related death and severity.

RESULTS

Of the 262 patients included, 108 (41.2%) required invasive ventilation, and 34 (13.0%) died in hospital. The diabetes group (n=92) was significantly older, more obese, had longer hospital stays, more severe illness, and higher mortality than the non-diabetes group (n=170). On multivariable logistic regression analysis, age (odds ratio (OR) 1.054 [95% confidence interval (CI) 1.023 - 1.086]), body mass index (OR 1.111 [95%CI 1.028 - 1.201]), history of diabetes mellitus (OR 2.429 [95%CI 1.152 - 5.123]), neutrophil count (OR 1.222 [95%CI 1.077 - 1.385]), CRP (OR 1.096 [95%CI 1.030 - 1.166]), and KL-6 (OR 1.002 [95%CI 1.000 - 1.003]) were predictors for COVID-19 severity (R² =0.468). Meanwhile, age (OR 1.104 [95%CI 1.037 - 1.175]) and KL-6 (OR 1.003 [95%CI 1.001 - 1.005]) were predictors for COVID-19-related death (R² =0.475).

CONCLUSIONS

Diabetes mellitus was a definite risk factor for COVID-19 severity in a single Japanese hospital treating moderately to severely ill patients.

Evolving Palliative Care Practices among Marshall Islanders in Hawai'i: Generational Comparisons

Little is known about Marshallese palliative care practices. We explored traditional and contemporary Marshallese palliative care practices and examined generational differences. We performed three focus groups in 2011-2012 among Marshall Islanders in Hawai'i. A native speaking interpreter assisted group facilitators. Data were analyzed using classical thematic triangulation methods to identify specific Marshallese palliative care practices, the effect of economic and social challenges in Hawai'i, and generational differences comparing young and old. Nineteen persons (10 men and 9 women, youth aged 17-27 years, and elders as defined in Marshallese culture, aged 46-79) participated. A "good death" was defined as "peaceful and pain free," occurring from natural causes. Factors associated with a "good death" included gathering of family to absolve conflicts, and proper and timely cultural practices. Factors associated with "bad deaths" included young age, active suffering, accidents, suicides, "black magic/curses," or lack of timely or proper burial. Comparing generational differences, older Marshallese had differing opinions regarding preferred place of death, burial site, cultural practice preservation, artificial prolongation of life, and cremation. Barriers included mortuary fees, cost of transporting bodies, United States (US) government policies, and wait times for death certificates. Many cultural factors contribute to "good" or "bad" deaths. Attitudes toward palliative care practices differ by generation. Having previously documented different approaches by Yapese, a generalized "one size fits all" approach to Micronesians is inappropriate. Overcoming identified barriers may facilitate practices necessary for a good death in Micronesian populations in their home nations and as they migrate to communities throughout the US.

Bulk and Surface Electronic Structure of the Dual-Topology Semimetal Pt_{2}HgSe_{3}

We report high-resolution angle-resolved photoemission measurements on single crystals of Pt_{2}HgSe_{3} grown by high-pressure synthesis. Our data reveal a gapped Dirac nodal line whose (001) projection separates the surface Brillouin zone in topological and trivial areas. In the nontrivial k-space range, we find surface states with multiple saddle points in the dispersion, resulting in two van Hove singularities in the surface density of states. Based on density-functional theory calculations, we identify these surface states as signatures of a topological crystalline state, which coexists with a weak topological phase.

Microfocus Laser-Angle-Resolved Photoemission on Encapsulated Mono-, Bi-, and Few-Layer 1T'-WTe2

Two-dimensional crystals of semi-metallic van der Waals materials hold much potential for the realization of novel phases, as exemplified by the recent discoveries of a polar metal in few-layer 1T'-WTe₂ and of a quantum spin Hall state in monolayers of the same material. Understanding these phases is particularly challenging because little is known from experiments about the momentum space electronic structure of ultrathin crystals. Here, we report direct electronic structure measurements of exfoliated mono-, bi-, and few-layer 1T'-WTe₂ by laser-based microfocus angle-resolved photoemission. This is achieved by encapsulating with monolayer graphene a flake of WTe₂ comprising regions of different thickness. Our data support the recent identification of a quantum spin Hall state in monolayer 1T'-WTe₂ and reveal strong signatures of the broken inversion symmetry in the bilayer. We finally discuss the sensitivity of encapsulated samples to contaminants following exposure to ambient atmosphere.

Effectiveness of sitagliptin in a patient with late dumping syndrome after total gastrectomy

An 83-year-old man developed hypoglycemia after undergoing total gastrectomy for gastric cancer in 200X-4. The patient was admitted to our hospital in May 200X and placed on continuous glucose monitoring (CGM). Glycemic excursions were examined while on 3-meal/day (1700kcal) and 6-meal/day (1800kcal) diets. Oxyhyperglycemia followed about 2h later by a sudden drop in glucose levels was seen with both regimens. These findings were consistent with late dumping syndrome. CGM was continued, oral miglitol at 150mg/day or sitagliptin at 50mg/day was started, and glycemic excursions were compared. Results were similar for both drugs, with reductions in postprandial glucose elevations. Meal tolerance testing 3 months after oral sitagliptin, compared to before starting treatment, showed reductions in both early postprandial hyperglycemia and insulin hypersecretion. These findings suggest that DPP-4 inhibitors such as sitagliptin may be effective for treating post-gastrectomy late dumping syndrome.

A facility for the analysis of the electronic structures of solids and their surfaces by synchrotron radiation photoelectron spectroscopy

A synchrotron radiation beamline in the photon energy range of 18-240 eV and an electron spectroscopy end station have been constructed at the 3 GeV Diamond Light Source storage ring. The instrument features a variable polarisation undulator, a high resolution monochromator, a re-focussing system to form a beam spot of 50 × 50 μm², and an end station for angle-resolved photoelectron spectroscopy (ARPES) including a 6-degrees-of-freedom cryogenic sample manipulator. The beamline design and its performance allow for a highly productive and precise use of the ARPES technique at an energy resolution of 10-15 meV for fast k-space mapping studies with a photon flux up to 2 ⋅ 10¹³ ph/s and well below 3 meV for high resolution spectra.

Tailoring the nature and strength of electron-phonon interactions in the SrTiO3(001) 2D electron liquid

Surfaces and interfaces offer new possibilities for tailoring the many-body interactions that dominate the electrical and thermal properties of transition metal oxides. Here, we use the prototypical two-dimensional electron liquid (2DEL) at the SrTiO3(001) surface to reveal a remarkably complex evolution of electron-phonon coupling with the tunable carrier density of this system. At low density, where superconductivity is found in the analogous 2DEL at the LaAlO3/SrTiO3 interface, our angle-resolved photoemission data show replica bands separated by 100 meV from the main bands. This is a hallmark of a coherent polaronic liquid and implies long-range coupling to a single longitudinal optical phonon branch. In the overdoped regime the preferential coupling to this branch decreases and the 2DEL undergoes a crossover to a more conventional metallic state with weaker short-range electron-phonon interaction. These results place constraints on the theoretical description of superconductivity and allow a unified understanding of the transport properties in SrTiO3-based 2DELs.

Person-centered Feeding Care: A Protocol to Re-introduce Oral Feeding for Nursing Home Patients with Tube Feeding

BACKGROUND

Although the literature on nursing home (NH) patients with tube feeding (TF) has focused primarily on the continuation vs. discontinuation of TF, the reassessment of these patients for oral feeding has been understudied. Re-assessing patients for oral feeding may be better received by families and NH staff than approaches focused on stopping TF, and may provide an opportunity to address TF in less cognitively impaired patients as well as those with end-stage conditions. However, the literature contains little guidance on a systematic interdisciplinary team approach to the oral feeding reassessment of patients with TF, who are admitted to NHs.

METHODS

This project had two parts that were conducted in one 170-bed intermediate/skilled, Medicare-certified NH in Honolulu, Hawai'i. Part 1 consisted of a retrospective observational study of characteristics of TF patients versus non-tube fed patients at NH admission (2003-2006) and longitudinal follow-up (through death or 6/30/2011) with usual care of the TF patients for outcomes of: feeding and swallowing reassessment, goals of care reassessment, feeding status (TF and/or per oral (PO) feedings), and hospice status. Part 2 involved the development of an interdisciplinary TF reassessment protocol through working group discussions and a pilot test of the protocol on a new set of patients admitted with TF from 2011-2014.

RESULTS

Part 1: Of 238 admitted patients, 13.4% (32/238) had TF. Prior stroke and lack of DNR status was associated with increased likelihood of TF. Of the 32 patients with TF at NH admission, 15 could communicate and interact (mild, moderate or no cognitive impairment with prior stroke or pneumonia); while 17 were nonverbal and/or bedbound patients (advanced cognitive impairment or terminal disease). In the more cognitively intact group, 9/15 (60%) were never reassessed for tolerance of oral diets and 10/15 (66.7%) remained with TF without any oral feeding until death. Of the end-stage group, 13/17 (76.5%) did not have goals of care reassessed and remained with TF without oral feeding until death. Part 2: The protocol pilot project included all TF patients admitted to the facility in 2011-2014 (N=33). Of those who were more cognitively intact (n=22), 21/22 (95.5%) had swallowing reassessed, 11/22 (50%) resumed oral feedings but 11 (50%) failed reassessment and continued exclusive TF. Of those with end-stage disease (n=11), 100% had goals of care reassessed and 9 (81.8%) families elected individualized oral feeding (with or without TF).

CONCLUSION

Using findings from our retrospective study of usual care, our NH's interdisciplinary team developed and pilot-tested a protocol that successfully reintroduced oral feedings to tube-fed NH patients who previously would not have resumed oral feeding.

Collapse of the Mott Gap and Emergence of a Nodal Liquid in Lightly Doped Sr(2)IrO(4)

We report angle resolved photoemission experiments on the electron doped Heisenberg antiferromagnet (Sr(1-x)La(x))(2)IrO(4). For a doping level of x=0.05, we find an unusual metallic state with coherent nodal excitations and an antinodal pseudogap bearing strong similarities with underdoped cuprates. This state emerges from a rapid collapse of the Mott gap with doping resulting in a large underlying Fermi surface that is backfolded by a (π,π) reciprocal lattice vector which we attribute to the intrinsic structural distortion of Sr(2)IrO(4).

Carrier-Density Control of the SrTiO3 (001) Surface 2D Electron Gas studied by ARPES

The origin of the 2D electron gas (2DEG)stabilized at the bare surface of SrTiO3 (001) is investigated. Using high-resolution angle-resolved photoemission and core-level spectroscopy, it is shown conclusively that this 2DEG arises from light-induced oxygen vacancies. The dominant mechanism driving vacancy formation is identified, allowing unprecedented control over the 2DEG carrier density.

Sitagliptin reduces the urine albumin-to-creatinine ratio in type 2 diabetes through decreasing both blood pressure and estimated glomerular filtration rate

BACKGROUND

We investigated the change in the urine albumin-to-creatinine ratio (ACR) to examine the effect of sitagliptin on diabetic nephropathy.

METHODS

Sitagliptin at a dose of 50 mg was administered to 247 outpatients with type 2 diabetes. Data were collected on the patients' laboratory results (including the ACR), blood pressure, and body weight. Clinical data were compared before and after 3 months' administration of sitagliptin.

RESULTS

The ACR changed from 150.0 ± 538.6 mg/gCre to 148.3 ± 764.6 mg/gCre over 3 months. In the patients with micro- and macro-albuminuria, the ACR after 3 months significantly decreased compared with the baseline (P = 0.04 and P = 0.02, respectively). The subjects whose ACR decreased experienced significantly larger decreases over the 3-month period in blood pressure and estimated glomerular filtration rate (eGFR) than the other subjects. There was no significant correlation between change in ACR (ΔACR) and change in hemoglobin A1c (ΔHbA1c) during 3 months (r = 0.04, P = 0.59), but there was a significant correlation between change in ΔACR and change in systolic blood pressure (r = 0.16, P = 0.03). Multiple regression analysis revealed that the significant predictors for ΔACR were change in systolic blood pressure (β = 0.21, P = 0.016) and change in eGFR (β = 0.20, P = 0.024) over 3 months (r = 0.35, P = 0.04).

CONCLUSIONS

Sitagliptin reduces the ACR through decreasing both blood pressure and eGFR, with no correlation with a decrease in HbA1c over a 3-month period. These results may reflect the direct action of sitagliptin on the kidneys.

Coherent quasiparticles with a small fermi surface in lightly doped Sr(3)Ir(2)O(7)

We characterize the electron doping evolution of (Sr_{1-x}La_{x})_{3}Ir_{2}O_{7} by means of angle-resolved photoemission. Concomitant with the metal insulator transition around x≈0.05 we find the emergence of coherent quasiparticle states forming a closed small Fermi surface of volume 3x/2, where x is the independently measured La concentration. The quasiparticle weight Z remains large along the entire Fermi surface, consistent with the moderate renormalization of the low-energy dispersion, and no pseudogap is observed. This indicates a conventional, weakly correlated Fermi liquid state with a momentum independent residue Z≈0.5 in lightly doped Sr_{3}Ir_{2}O_{7}.

Control of a two-dimensional electron gas on SrTiO₃(111) by atomic oxygen

We report on the formation of a two-dimensional electron gas (2DEG) at the bare surface of (111) oriented SrTiO3. Angle resolved photoemission experiments reveal highly itinerant carriers with a sixfold symmetric Fermi surface and strongly anisotropic effective masses. The electronic structure of the 2DEG is in good agreement with self-consistent tight-binding supercell calculations that incorporate a confinement potential due to surface band bending. We further demonstrate that alternate exposure of the surface to ultraviolet light and atomic oxygen allows tuning of the carrier density and the complete suppression of the 2DEG.

Epithelioid inflammatory myofibroblastic sarcoma responsive to surgery and an ALK inhibitor in a patient with panhypopituitarism

We encountered a case of epithelioid inflammatory myofibroblastic sarcoma (EIMS) originating from an abdominal organ that rapidly regrew twice. The patient underwent two surgeries. Large tumors grew within three months after the second surgery. The patient subsequently received chemotherapy with an anaplastic lymphoma kinase (ALK) inhibitor. Although EIMS has a poor prognosis, the patient continues to be alive with disease 14 months after surgical treatment and the administration of the ALK inhibitor.

Prevalence of vitamin D deficiency and association with functional status in newly admitted male veteran nursing home residents

OBJECTIVES

To provide the first report on prevalence of vitamin D deficiency in newly admitted nursing home (NH) residents and associations with functional disabilities and chronic diseases.

DESIGN

Retrospective chart review.

SETTING

Nursing home (NH).

PARTICIPANTS

Male veterans newly admitted to a NH for rehabilitation, skilled-nursing care, intermediate care, or respite care between January 2011 and June 2012.

MEASUREMENTS

Total serum 25-hydroxyvitamin D (25(OH)D) levels were measured on admission. Vitamin D supplement users and those without 25(OH)D measurement within 7 days of admission were excluded, leaving an analytical sample of 104 residents. Vitamin D deficiency was defined as 25(OH)D less than 20 ng/mL. Data were collected on age, ethnicity, season, body mass index (BMI), functional disability in activities of daily living (ADLs) (mobility, bathing, dressing, toileting, continence, and feeding), and prevalent chronic diseases.

RESULTS

Prevalence of vitamin D deficiency was 49.0%. In multivariate logistic regression models adjusted for age, ethnicity, and BMI, vitamin D deficiency was significantly associated with number of ADL disabilities (odds ratio (OR) = 1.4 for each 1-point increase in ADL disability score, P = .03) and prevalent diabetes mellitus (OR = 3.0, P = .03). In regression models using each ADL disability as a separate variable, only disability in feeding (OR = 4.7, P = .05) and diabetes mellitus (OR = 2.9, P = .04) remained significant.

CONCLUSION

Almost half the individuals entering the NH and not taking vitamin D supplements had vitamin D deficiency. Greater number of ADL disabilities, disability in feeding, and prevalent diabetes mellitus were independently associated with vitamin D deficiency.

Structural origin of apparent Fermi surface pockets in angle-resolved photoemission of Bi₂Sr(2-x)La(x)CuO(6+δ)

We observe apparent hole pockets in the Fermi surfaces of single-layer Bi-based cuprate superconductors from angle-resolved photoemission. From detailed low-energy electron diffraction measurements and an analysis of the angle-resolved photoemission polarization dependence, we show that these pockets are not intrinsic but arise from multiple overlapping superstructure replicas of the main and shadow bands. We further demonstrate that the hole pockets reported recently from angle-resolved photoemission [Meng et al., Nature (London) 462, 335 (2009)] have a similar structural origin and are inconsistent with an intrinsic hole pocket associated with the electronic structure of a doped CuO₂ plane.

Creation and control of a two-dimensional electron liquid at the bare SrTiO3 surface

Many-body interactions in transition-metal oxides give rise to a wide range of functional properties, such as high-temperature superconductivity, colossal magnetoresistance or multiferroicity . The seminal recent discovery of a two-dimensional electron gas (2DEG) at the interface of the insulating oxides LaAlO(3) and SrTiO(3) (ref. 4) represents an important milestone towards exploiting such properties in all-oxide devices. This conducting interface shows a number of appealing properties, including a high electron mobility, superconductivity and large magnetoresistance, and can be patterned on the few-nanometre length scale. However, the microscopic origin of the interface 2DEG is poorly understood. Here, we show that a similar 2DEG, with an electron density as large as 8×10(13)  cm(-2), can be formed at the bare SrTiO(3) surface. Furthermore, we find that the 2DEG density can be controlled through exposure of the surface to intense ultraviolet light. Subsequent angle-resolved photoemission spectroscopy measurements reveal an unusual coexistence of a light quasiparticle mass and signatures of strong many-body interactions.

Strong electron correlations in the normal state of the iron-based FeSe0.42Te0.58 superconductor observed by angle-resolved photoemission spectroscopy

We investigate the normal state of the "11" iron-based superconductor FeSe0.42Te0.58 by angle-resolved photoemission. Our data reveal a highly renormalized quasiparticle dispersion characteristic of a strongly correlated metal. We find sheet dependent effective carrier masses between approximately 3 and 16m{e} corresponding to a mass enhancement over band structure values of m{*}/m{band} approximately 6-20. This is nearly an order of magnitude higher than the renormalization reported previously for iron-arsenide superconductors of the "1111" and "122" families but fully consistent with the bulk specific heat.

[TVT and TOT: a comparison between these two techniques based on our clinical experience]

A retrospective evaluation and a comparison of results from two minimally invasive surgery techniques that we adopted for the treatment of SUI. MATERIALS AND METHODS. In this study we evaluated 113 selected patients who underwent SUI minimally invasive surgery from 1-1-2000 to 31-12-2007. 87 patients underwent epidural anesthesia. 26 local anesthesia. In Group A (TVT) 61 patients were enrolled, mean age 57.6 (±22). 43 patients (70%) were on menopause. In Group B (TOT out-in) 52 patients were enrolled (for 34 of them we used the Obtape® sling while for 18 the Obtryx® one), their mean age was 58.5 (±20.5) and 39 patients (75%) were on menopause. Patients from both groups did not undergo any past previous urogynecological surgery and suffered from stress urinary incontinence with cervico-urethral hypermobility butno other associated pathology. The pre-operative work-up included an evaluation of patients based on ICS guidelines. RESULTS. Group A (TVT) - mean follow-up 66.3 months, dry patients 53/61 (86.8%). Bladder perforations resolved by catheterization 3/61 (5%). Transient voiding dysfunction 14/61 (22.8%). "De novo" urgency 8/61 (13%). One patient on self-catheterization due to persistent urinary retention underwent a single-side section of the sling with spontaneous micturition and complete continence recovery. Group B (TOT out-in) - mean follow-up 35.5 months, dry patients 43/52 (82%). 4 patients (7.6%) complained oftransient voiding dysfunction, 5 patients (9.5%) for "de novo" urgency, 1 patient underwent a sling removal due to vaginal erosion 4 months after surgery (Obtape®).

TVT and TOT: a comparison between these two techniques based on our clinical experience

Aim of the Study

A retrospective evaluation and a comparison of results from two minimally invasive surgery techniques that we adopted for the treatment of SUI.

Materials and Methods.

In this study we evaluated 113 selected patients who underwent SUI minimally invasive surgery from 1–1-2000 to 31–12–2007. 87 patients underwent epidural anesthesia. 26 local anesthesia. In Group A (TVT) 61 patients were enrolled, mean age 57.6 (±22). 43 patients (70%) were on menopause. In Group B (TOT out-in) 52 patients were enrolled (for 34 of them we used the Obtape® sling while for 18 the Obtryx® one), their mean age was 58.5 (±20.5) and 39 patients (75%) were on menopause. Patients from both groups did not undergo any past previous urogynecological surgery and suffered from stress urinary incontinence with cervico-urethral hypermobility butno other associated pathology. The pre-operative work-up included an evaluation of patients based on ICS guidelines.

Results.

Group A (TVT) - mean follow-up 66.3 months, dry patients 53/61 (86.8%). Bladder perforations resolved by catheterization 3/61 (5%). Transient voiding dysfunction 14/61 (22.8%). “De novo” urgency 8/61 (13%). One patient on self-catheterization due to persistent urinary retention underwent a single-side section of the sling with spontaneous micturition and complete continence recovery. Group B (TOT out-in) - mean follow-up 35.5 months, dry patients 43/52 (82%). 4 patients (7.6%) complained oftransient voiding dysfunction, 5 patients (9.5%) for “de novo” urgency, 1 patient underwent a sling removal due to vaginal erosion 4 months after surgery (Obtape®).

Fermi surface and van Hove singularities in the itinerant Metamagnet Sr3Ru2O7

The low-energy electronic structure of the itinerant metamagnet Sr3Ru2O7 is investigated by angle-resolved photoemission and density-functional calculations. We find well-defined quasiparticle bands with resolution-limited linewidths and Fermi velocities up to an order of magnitude lower than in single layer Sr2RuO4. The complete topography, the cyclotron masses, and the orbital character of the Fermi surface are determined, in agreement with bulk sensitive de Haas-van Alphen measurements. An analysis of the dxy band dispersion reveals a complex density of states with van Hove singularities near the Fermi level, a situation which is favorable for magnetic instabilities.

Bulk superconductivity at 38 K in a molecular system

C(60)-based solids are archetypal molecular superconductors with transition temperatures (Tc) as high as 33 K (refs 2-4). Tc of face-centred-cubic (f.c.c.) A(3)C(60) (A=alkali metal) increases monotonically with inter C(60) separation, which is controlled by the A(+) cation size. As Cs(+) is the largest such ion, Cs(3)C(60) is a key material in this family. Previous studies revealing trace superconductivity in Cs(x)C(60) materials have not identified the structure or composition of the superconducting phase owing to extremely small shielding fractions and low crystallinity. Here, we show that superconducting Cs(3)C(60) can be reproducibly isolated by solvent-controlled synthesis and has the highest Tc of any molecular material at 38 K. In contrast to other A(3)C(60) materials, two distinct cubic Cs(3)C(60) structures are accessible. Although f.c.c. Cs(3)C(60) can be synthesized, the superconducting phase has the A15 structure based uniquely among fullerides on body-centred-cubic packing. Application of hydrostatic pressure controllably tunes A15 Cs(3)C(60) from insulating at ambient pressure to superconducting without crystal structure change and reveals a broad maximum in Tc at approximately 7 kbar. We attribute the observed Tc maximum as a function of inter C(60)separation--unprecedented in fullerides but reminiscent of the atom-based cuprate superconductors--to the role of strong electronic correlations near the metal-insulator transition onset.

Inducible virus-mediated expression of a foreign protein in suspension-cultured plant cells

Although suspension-cultured plant cells have many potential merits as sources of useful proteins, the lack of an efficient expression system has prevented using this approach. In this study, we established an inducible tomato mosaic virus (ToMV) infection system in tobacco BY-2 suspension-cultured cells to inducibly and efficiently produce a foreign protein. In this system, a modified ToMV encoding a foreign protein as replacement of the coat protein is expressed from stably transformed cDNA under the control of an estrogen-inducible promoter in transgenic BY-2 cells. Estrogen added to the culture activates an estrogen-inducible transactivator expressed constitutively from the transgene and induces transcription and replication of viral RNA. In our experiments, accumulation of viral RNA and expression of green fluorescent protein (GFP) encoded in the virus were observed within 24 h after induction. The amount of GFP reached approximately 10% of total soluble protein 4 d after induction. In contrast, neither viral RNA nor GFP were detected in uninduced cells. The inducible virus infection system established here should be utilized not only for the expression of foreign proteins, but also for investigations into the viral replication process in cultured plant cells.

Boron Nitride Nanomesh

A highly regular mesh of hexagonal boron nitride with a 3-nanometer periodicity and a 2-nanometer hole size was formed by self-assembly on a Rh(111) single crystalline surface. Two layers of mesh cover the surface uniformly after high-temperature exposure of the clean rhodium surface to borazine (HBNH)3. The two layers are offset in such a way as to expose a minimum metal surface area. Hole formation is likely driven by the lattice mismatch of the film and the rhodium substrate. This regular nanostructure is thermally very stable and can serve as a template to organize molecules, as is exemplified by the decoration of the mesh by C60 molecules.

Cell-to-cell movement of Potato virus X: the role of p12 and p8 encoded by the second and third open reading frames of the triple gene block

Potato virus X (PVX) requires three proteins, p25, p12, and p8, encoded by the triple gene block plus the coat protein (CP) for cell-to-cell movement. When each of these proteins was co-expressed with a cytosolic green fluorescent protein (GFP) in the epidermal cells of Nicotiana benthamiana by the microprojectile bombardment-mediated gene delivery method, only p12 enhanced diffusion of co-expressed GFP, indicating an ability to alter plasmodesmal permeability. p25, p12, and CP, expressed transiently in the initially infected cells, transcomplemented the corresponding movement-defective mutants to spread through two or more cell boundaries. Thus, these proteins probably move from cell to cell with the genomic RNA. In contrast, p8 only functioned intracellularly and was not absolutely required for cell-to-cell movement. Since overexpression of p12 overcame the p8 deficiency, p8 appears to facilitate the functioning of p12, presumably by mediating its intracellular trafficking. Considering the likelihood that p12 and p8 are membrane proteins, it is suggested that intercellular as well as intracellular movement of PVX involves a membrane-mediated process.

Management of posterior capsule rupture during phacoemulsification using the dry technique

To manage posterior capsule rupture during phacoemulsification, we use a dry technique in which all procedures are performed without an irrigation/aspiration system. The dry technique is characterized by (1) continuous viscoelastic injection instead of fluid irrigation to maintain anterior chamber depth with the posterior capsule and vitreous located posteriorly and (2) static removal of most residual lens material by viscoexpression and/or manual small incision extracapsular cataract extraction without aspiration and dynamic water flow. In 16 cases of posterior capsule rupture managed using the dry technique, the residual nucleus and cortex were readily removed with minimum extension of the ruptured area and new vitreous loss. Although large amounts of viscoelastic material (mean 5.8 mL) were required, rapid and stable visual recovery was comparable to that in patients having uneventful surgery. The dry system is a safe and reliable technique for managing posterior capsule rupture during phacoemulsification.

Tobamoviral movement protein transiently expressed in a single epidermal cell functions beyond multiple plasmodesmata and spreads multicellularly in an infection-coupled manner

Cell-to-cell movement of a plant virus requires expression of the movement protein (MP). It has not been fully elucidated, however, how the MP functions in primary infected cells. With the use of a microprojectile bombardment-mediated DNA infection system for Tomato mosaic virus (ToMV), we found that the cotransfected ToMV MP gene exerts its effects in the initially infected cells and in their surrounding cells to achieve multicellular spread of movement-defective ToMV. Five other tobamoviral MPs examined also transcomplemented the movement-defective phenotype of ToMV, but the Cucumber mosaic virus 3a MP did not. Together with the cell-to-cell movement of the mutant virus, a fusion between the MP and an enhanced green fluorescent protein variant (EGFP) expressed in trans was distributed multicellularly and localized primarily in plasmodesmata between infected cells. In contrast, in noninfected sites the MP-EGFP fusion accumulated predominantly inside the bombarded cells as irregularly shaped aggregates, and only a minute amount of the fusion was found in plasmodesmata. Thus, the behavior of ToMV MP is greatly modulated in the presence of a replicating virus and it is highly likely that the MP spreads in the infection sites, coordinating with the cell-to-cell movement of the viral genome.

Guided knives

A new type of knife that enables a surgeon to easily create tunnel-shaped incisions with a prescribed depth has been developed. The knife features an incision guide, the arm of which extends just beyond the tip of the blade. The space between the blade and the arm can be set at the desired width. By moving the knife as if sliding the arm across the corneal or scleral surface, the blade can move to a certain depth from the surface. The guided knife enables even novice surgeons to easily make a self-sealing incision during cataract surgery. In addition, the innovative nature of this device seems to be applicable to many other surgeries that require a partial-thickness incision.

AHM1, a novel type of nuclear matrix-localized, MAR binding protein with a single AT hook and a J domain-homologous region

Interactions between the nuclear matrix and special regions of chromosomal DNA called matrix attachment regions (MARs) have been implicated in various nuclear functions. We have identified a novel protein from wheat, AT hook-containing MAR binding protein1 (AHM1), that binds preferentially to MARs. A multidomain protein, AHM1 has the special combination of a J domain-homologous region and a Zn finger-like motif (a J-Z array) and an AT hook. For MAR binding, the AT hook at the C terminus was essential, and an internal portion containing the Zn finger-like motif was additionally required in vivo. AHM1 was found in the nuclear matrix fraction and was localized in the nucleoplasm. AHM1 fused to green fluorescent protein had a speckled distribution pattern inside the nucleus. AHM1 is most likely a nuclear matrix component that functions between intranuclear framework and MARs. J-Z arrays can be found in a group of (hypothetical) proteins in plants, which may share some functions, presumably to recruit specific Hsp70 partners as co-chaperones.

Role of Pseudomonas aeruginosa culture filtrates in the association, invasion, and cytotoxicity against cloned cells from murine corneal epithelium and KB cells

PURPOSE

To clarify the effect of Pseudomonas aeruginosa culture filtrates on the association with, invasion into, and cytotoxicity against cloned cells from murine corneal epithelial cells and KB cells.

METHODS

Simian virus 40-transformed murine corneal epithelial (MCE) cells were established. Murine corneal epithelial cells and KB cells were infected with a protease-positive strain, IID1117 (Pa IID1117), and a protease-negative strain, IID1130 (Pa IID1130) of P. aeruginosa, and then tested for association and invasion of Pa IID1117. The cytotoxicity test was performed by incubating the cells with culture filtrate.

RESULTS

Association of Pa IID1117 with KB cells pretreated with Pa IID1130 was significantly promoted. After pretreatment with culture filtrate, invasion was more effective into MCE cells than into KB cells. When infecting bacteria (Pa IID1117) were pretreated with protease inhibitor, invasion of the bacteria into MCE cells and KB cells clearly decreased. The cellular damage induced by the culture filtrate of Pa IID1130 was greater than the damage by that of Pa IID1117.

CONCLUSION

These results suggest that association of P. aeruginosa with MCE cells and KB cells was influenced by the culture filtrates other than proteases, and that invasion of P. aeruginosa into MCE cells and KB cells was promoted by protease.

Expression of stress-response protein 60 in iritis associated with experimental autoimmune encephalomyelitis

PURPOSE

To study the expression of stress-response proteins in the inflamed iris of rats with experimental autoimmune encephalomyelitis (EAE).

METHODS

EAE was induced in Lewis rats by immunization with homogenized spinal cord of the guinea pig emulsified in complete Freund's adjuvant (CFA) (group EAE). Control rats included those immunized with only CFA (group CFA) and those that were untreated (group Normal). Immunohistochemical study for the localization of stress-response protein (srp) 27, srp 60, srp 72, ubiquitin, and alphaB-crystallin was performed.

RESULTS

All rats in group EAE developed iritis, whereas none of the rats in group CFA and group Normal developed iritis. No expression of ubiquitin, alphaB-crystallin, srp 27, srp 60, or srp 72 was seen in the epithelium of the iris in group CFA rats. In the eyes of rats in group EAE, srp 60 was expressed in the epithelium of the iris in 20 of 22 (90.9%), ubiquitin in 4 of 22 (18.2%), and alphaB-crystallin in 3 of 22 (13.6%). In the group Normal rats, only ubiquitin was expressed in the epithelium of the iris in 1 of 6 (16.7%) eyes examined.

CONCLUSIONS

These results suggest that srp 60 may be a potential uveitogenic antigen in the iris in EAE.

Expression of stress-response protein 60 in lens epithelial cells in atopic cataract

PURPOSE

To clarify the pathogenesis of atopic cataract, especially to determine if there is any relationship between autoimmunity and atopic cataract.

METHODS

We investigated the lens epithelia obtained at surgery from 12 patients (12 eyes) with atopic cataract: from 8 patients (8 eyes) with nonatopic cataract (5 with senile cataract, 2 with juvenile cataract, and one with secondary cataract due to anterior uveitis); and from 4 autopsy eyes as controls.

RESULTS

Histopathological findings in the lens epithelial cells from atopic and nonatopic cataract patients were essentially the same: atrophy of the cells, presence of the superimposed cells, migration of cells into the lens cortex, cytoplasmic vacuolation, and loss of cells. In an immunohistochemical study, the expression of stress-response protein 60 (srp 60), srp 27, and srp 72 was examined in the lens epithelial cells. In atopic cataract specimens, 71%-87% of the lens epithelial cells were stained with the antibody against srp 60, but the cells in nonatopic cataract and control specimens were not stained.

CONCLUSIONS

Srp 27 and srp 72 were not expressed in any observed epithelial cells. The expression of srp 60 may reflect a protective mechanism of the epithelial cells against injury triggered by immunorelated agents. These findings suggest that the pathogenesis of degeneration of the lens epithelial cells in patients with atopic cataract may be related to autoimmunity.

Cyclic 3',5'-guanosine monophosphate synthesis induced by atrial natriuretic peptide, C-type natriuretic peptide, and nitric oxide in the rat retina

This study was undertaken to determine whether pathways exist in the rat retina for atrial natriuretic peptide (ANP)-, C-type natriuretic peptide (CNP)-, and nitric oxide (NO)- cyclic 3', 5'-guanosine monophosphate (cGMP). Exposure of the retina to ANP (10(-7) mol/L), CNP (10(-7) mol/L), S-nitroso-N-acetylpenicillamine (10(-5) mol/L, SNAP; a NO donor), A23187 (10(-5)mol/L; a Ca2+ ionophore), and carbachol (10(-3) mol/L) caused 1.45 approximately 1.67-fold increases in cGMP content (P < .01). The increase in cGMP content induced by A23187 was blocked by 2-4-carboxyphenyl . 4455-tetramethyl imidazoline 1-oxyl 3-oxide (10(-3) mol/ L, carboxy-PTIO; a NO scavenger). Both carboxy-PTIO (10(-3) mol/L) and NG-nitro-L-arginine (10(-3) mol/L, L-NNA: a NO synthase inhibitor) blocked the increase in cGMP content induced by carbachol. Atropine (10(-50 mol/L; a muscarinic receptor antagonist) also blocked the cGMP increase induced by carbachol. These data demonstrate that ANP-, CNP-, and NO-cGMP pathways exist in the rat retina and that the NO-cGMP pathway may be linked to the activation of the muscarinic receptor.

Laparoscopic “en-bloc” ligation of spermatic veins

Laparoscopic varicocelectomy is suggested only for II-III grade bilateral varicocele. The optical magnification granted by videosurgical techniques, prevents damaging testicular arteries; this possibility, however, requires a considerable amount of time. We performed a laparoscopic “en-bloc” ligation without sparing the artery on 13 patients with bilateral varicocele in order to assess eventual changes in gonadal volume. 10 patients underwent bilateral “en-bloc” ligation of spermatic vessels with an average operating time of 21 minutes. In 3 other patients, “en-bloc” ligation was performed on the right side while on the left side the artery was identified and saved; in these cases the average operating time was 33 minutes. After an average follow-up period of 19 months no cases of testicle atrophy nor of hydrocele were reported. ColorDoppler sonography, performed 3 months later on the 10 patients treated by bilateral “en-bloc” ligation, showed no persistent reflux. No case of homolateral persistent reflux was encountered in the 3 patients who underwent only right-side “en-bloc” ligation, but on the left side, where selective ligation had been performed, persistence of reflux was registered in one patient. Our experience has confirmed that laparoscopic “en-bloc” ligation of the internal spermatic pedicle, sparing vasa deferentia, prevents the persistence of reflux in all cases and allows a reduction in operating time. The opportunity of treating a pathology like bilateral varicocele by means of laparoscopy, which requires general anaesthesia, needs further confirmation and a larger number of case histories.

Correction of stress urinary incontinence: laparoscopy combined with vaginal suturing

The authors review the published techniques of laparoscopic colposuspension combined with vaginal suturing. Particular emphasis is given to their own technique, first published in 1992, and to that of Harewood (1993), which is similar. Both involve a Burch-like colposuspension using a technique similar to that of Gittes and Loughlin. This is possible looking inside the pelvis through a laparoscope and using a handle-needle. Published results are similar (about 70% success rate), but the authors point out that the Breda technique is simpler, cheaper, and less time consuming (only one trocar instead of three) and has had a longer follow-up (up to 3 years instead of 19 months). The authors review many other similar techniques reported between 1993 and 1995 with good results but based on rather limited experience. The conclusion is that the laparoscopic technique with vaginal suturing seems a promising way to approach stress urinary incontinence in the female patient.

Laparoscopic nephrectomy: Our personal experience on 39 cases

The authors, six years after the first laparoscopic nephrectomy by Clayman and five years after their own first case in Italy, review the literature and their personal experience in 39 cases. In their opinion, today's situation can be summed up by the conclusion that laparoscopic nephrectomy for benign disease is a safe, reproducible, cost-effective procedure and can be recommended as the procedure of choice for young ladies with a small, afunctional kidney. The same is not true for malignant diseases which, in the authors’ opinion, must be a matter for prospective, randomised and well-controlled clinical trials in reference centres.