Nonlinear optical responses in two-dimensional transition metal dichalcogenide multilayer: WS2, WSe2, MoS2 and Mo0.5W0.5S2: publisher's note.

This publisher's note amends the Funding section of a recent publication [Opt. Express24, 20685 (2016].

Nonlinear optical responses in two-dimensional transition metal dichalcogenide multilayer: WS2, WSe2, MoS2 and Mo 0.5 W0.5 S2.

Synthetic two-dimensional transition metal dichalcogenides such as, tungsten disulphide (WS2), tungsten diselenide (WSe2), molybdenum disulphide (MoS2) as well as mixed molybdenum tungsten disulphide (Mo0.5W0.5S2) single crystals were grown by the chemical vapor transport method using halogens (bromine or chlorine) as transport agents. Multi- layer samples were cleaved from the single crystals, and their nonlinear optical (NLO) properties were obtained from both open aperture and closed aperture Z-scan measurements using a picosecond mode-locked Nd: YAG laser operating at a wavelength of 1064 nm, with pulse duration of 25 ps, and 20 Hz repetition rate. Both WS2 and MoS2 exhibited nonlinear saturable absorption (SA), whereas WSe2 and Mo0.5W0.5S2 showed nonlinear two-photon absorption (2PA). A large 2PA coefficient ß as high as + 1.91x10-8 cm/W was obtained for the Mo0.5W0.5S2, and an index of refraction coefficient γ = -2.47x10-9 cm2/W was obtained for the WSe2 sample.

[Refractive errors among schoolchildren in the central region of Togo]. / Amétropies en milieu scolaire dans la région centrale du Togo.

Untreated refractive errors represent the main visual impairment in the world but also the easiest to avoid. The goal of this survey is to use clinical and epidemiological data to efficiently plan distribution of corrective glasses in a project supported by the Swiss Red Cross in the central region of Togo. To achieve this goal, 66 primary schools were identified randomly in the catchment area of the project. The teachers at these schools were previously trained to test visual acuity (VA). The schoolchildren referred by these teachers were examined by eye care professionals. The schoolchildren with ametropia (VA≤7/10 in at least one eye) underwent cycloplegic autorefraction. Of a total of 19,252 registered schoolchildren, 13,039 underwent VA testing by the teachers (participation rate=68%). Among them, 366 cases of ametropia were identified (prevalence about 3%). The average age of the schoolchildren examined was 10.7±2.3years, with a sex ratio of 1.06. Autorefraction, which was performed for 37% of the schoolchildren with ametropia allowed them to be classified into three groups: hyperopia (4%), myopia (5%) and astigmatism of all types (91%). Regardless of the type of ametropia, the degree of severity was mild in 88%. The results of this survey have highlighted the importance of the teachers' contribution to eye care education in the struggle against refractive errors within the school environment, as well as helping to efficiently plan actions against ametropia.

Amplification of higher-order modes by stimulated Raman scattering in H2-filled hollow-core photonic crystal fiber.

We report a method for amplifying higher-order guided modes, synthesized with a spatial light modulator, in a hydrogen-filled hollow-core photonic crystal fiber. The gain mechanism is intermodal stimulated Raman scattering, a pump laser source in the fundamental mode providing amplification for weak higher-order seed modes at the Stokes frequency. The gain for higher-order modes up to LP31 is calculated and verified experimentally.

Generation of a phase-locked Raman frequency comb in gas-filled hollow-core photonic crystal fiber.

In a relatively simple setup consisting of a microchip laser as pump source and two hydrogen-filled hollow-core photonic crystal fibers, a broad, phase-locked, purely rotational frequency comb is generated. This is achieved by producing a clean first Stokes seed pulse in a narrowband guiding photonic bandgap fiber via stimulated Raman scattering and then driving the same Raman transition resonantly with a pump and Stokes fields in a second broadband guiding kagomé-style fiber. Using a spectral interferometric technique based on sum frequency generation, we show that the comb components are phase locked.

Long-term persisting interferon beta-1b neutralizing antibodies after discontinuation of treatment.

OBJECTIVES: Neutralizing antibodies (NAB) against interferon beta (IFNB) with presumably negative impact on treatment outcome have been described in up to 42% of patients undergoing IFNB treatment. However, in most cases NAB decrease despite continuation of IFNB therapy. Observations on NAB after discontinuation of IFNB therapy are lacking. Here, we report for the first time on NAB which now persist for several years following discontinuation of IFNB treatment. MATERIALS AND METHODS: We present two multiple sclerosis patients followed over 8 and 10 years. NAB have been measured repeatedly and are presented together with clinical data. NAB developed after 2 years of treatment and persisted despite discontinuation of treatment at high titers for more than 4 years. CONCLUSION: Our data indicate that IFNB therapy may induce long-term NAB production which persists even after discontinuating IFNB treatment. Possible immunological mechanisms are discussed.

[Ileocecal invagination of a mucocele of the appendix]. / Ileozökale Darminvagination bei Mukozele der Appendix.

HISTORY AND CLINICAL FINDINGS: A 39-year-old patient was admitted because of pain in the right mid and lower abdomen of 2 weeks duration with vomiting and postprandial nausea. He complained of changing stool habits with diarrhoea and constipation. Clinically he showed a slight tenderness in the right lower abdomen. INVESTIGATIONS: Routine laboratory test were normal including CRP and WBC. Ultrasound showed a non-compressible mass with low intensity echoes, 3.6 x 4.6 cm in diameter in the right mid abdomen, slightly tender, surrounded by a circular, intestine-like structure. A gastrografin-swallow didn't reveal any obstacle in the proximal small intestine and was inconclusive further distal. A CT scan demonstrated a ileocoecal invagination extending in the colon ascendens to the right flexure with suspicion of a tumor. At the colonoscopy on the next day the invagination was not apparent any more, but a well-rounded tumour in the appendix region was seen. DIAGNOSIS, TREATMENT AND COURSE: Suspecting a coecal tumour with remitting ileocoecal invagination a ileocoecal resection was performed on the third day. The tumour proved to be a mass of mucus with parts of a villo-mucinous cystadenoma of the UMP type. Recovery was uneventful. CONCLUSION: Mucoceles of the appendix can cause ileocoecal invagination in the adult.

[Ulcerating scrotal leiomyoma]. / Ulzeriertes skrotales Leiomyom.

A 74-years old patient is admitted to the hospital with a over a period of 4 years growing, scrotal, ulcerated tumor. There is no connection to the testicle or the epididymis palpable. All laboratory findings including the tumorparameters are normal. The scrotal sonography shows a solid tumor, that is filled with vessels in the Doppler sonography. The complete tumor resection with histological examination leads to the diagnosis of a scrotal leiomyoma. This rare, benign tumor is a differential diagnosis to paratesticular or non-germinal tumors.

Severe inflammatory upper airway stenosis in ulcerative colitis.

Severe upper airway stenosis was diagnosed in a 23 year old woman who presented with hoarseness, cough and dyspnoea 8 yrs after initial diagnosis of ulcerative colitis. The respiratory symptoms worsened over the next few months, the patient eventually developing dysphagia and ultimately severe upper airway obstruction. The narrowest site was the glottis, which was severely stenosed by inflammatory swellings. Systemic corticosteroids led to rapid clinical improvement and restoration of normal airway patency within a few months. Ulcerative colitis is frequently associated with extraintestinal inflammatory manifestations. In the respiratory tract these usually take the form of chronic bronchitis, which occasionally develops into bronchiectasis. This case confirms that the inflammation can also involve the larynx and large airways.

Neutralizing interferon beta antibodies in melanoma patients treated with recombinant and natural interferon beta.

The incidence and clinical significance of therapy-induced neutralizing interferon beta (IFN beta) antibodies was studied in a group of 21 melanoma patients treated with natural IFN beta and 7 patients treated with recombinant IFN beta. They were treated subcutaneously with 3 x 10(6) IU three times per week in an adjuvant open trial for 24 weeks after surgical removal of all detectable metastases. Of the 21 patients treated with natural IFN beta, 95% developed significant levels of neutralizing antibodies after 24 weeks. In comparison, 28% of the 7 patients treated with recombinant IFN beta developed neutralizing IFN beta antibodies. Cross-reactivity of the antibodies could be demonstrated. Persistence of antibody titers was seen in 80% of the patients 24 weeks after cessation of treatment with natural IFN beta. No correlation between the maximum antibody titers and the antibody persistence after cessation of therapy could be established. We detected a clear correlation between the formation of neutralizing antibodies and the decrease in beta 2-microglobulin and 2',5'-oligoadenylate synthetase and therefore the drop in biological activity. In this adjuvant trial there was no difference in relapse rate and time until relapse between antibody-positive and antibody-negative patients. No difference in clinical outcome could be established between the patients treated with natural IFN beta and recombinant IFN beta.

Imidazenil: a new partial positive allosteric modulator of gamma-aminobutyric acid (GABA) action at GABAA receptors.

Positive allosteric modulators of gamma-aminobutyric acid (GABA)A receptors, including benzodiazepines and congeners, can be classified into three categories: 1) full allosteric modulators (i.e., triazolam and alprazolam) that act with high potency and efficacy at many GABAA receptors; 2) selective allosteric modulators (i.e., diazepam) that act with high potency and high efficacy at selected GABAA receptors; and 3) partial allosteric modulators (i.e., bretazenil) that act with high potency but low efficacy at many GABAA receptors. Imidazenil, an imidazobenzodiazepine carboxamide, has been characterized as a novel representative of the partial allosteric modulator class. When tested on a broad spectrum (native and recombinant) of GABAA receptors, imidazenil positively modulates the GABA-elicited Cl- currents with a 4- to 5-fold higher potency but an efficacy (30-50%) lower than that of diazepam, and it antagonizes the effects of the latter drug. Imidazenil in vitro (Ki = 5 x 10(-10) M) and in vivo (ID50 = 0.2 mumol/kg i.v.) displaces [3H]flumazenil from its brain binding sites and in vivo it possesses a marked anticonflict profile in the rat Vogel conflict-punishment test and is 10 times more potent than bretazenil and 100 times more potent than diazepam or alprazolam in antagonizing bicuculline- and pentylenetetrazol-induced seizures. Unlike diazepam and alprazolam, which induce sedation and ataxia and potentiate the effects of ethanol and thiopental at doses similar to those that produce anticonflict effects and occupy 50% of brain flumazenil binding sites, imidazenil does not produce ataxia or sedation in rats nor does it potentiate the effects of ethanol or thiopental in doses 30- to 50-fold higher than those required for the anticonflict effect and for 100% occupancy of brain flumazenil binding sites. Furthermore, when administered with diazepam, imidazenil blocks in a dose-related fashion the sedative, ataxic effects of this drug and thus acts on these unwanted responses as an antagonist (i.e., like flumazenil). In all tests, imidazenil has the pharmacological profile of a partial allosteric modulator, but is more potent than bretazenil, has a longer biological half-life and, in rodents, is virtually unable to cause sedation, ataxia or to potentiate ethanol toxicity.

Differential antagonism of platelet activating factor-induced neutrophilia and gastric hemorrhage in the rat.

Intravenous injection of platelet activating factor (PAF) in rats produced hypotension, neutrophilia, gastric congestion, and sloughing of the gastric epithelium. The congestion was quantified by measuring hemoglobin in the gastric mucosa. Other lesions were quantified by scores of gross pathology and histopathology. PAF-induced changes in neutrophil levels were prevented by pretreatment with the PAF-antagonist Ro24-4736, but not by the PAF-antagonist CV-3988. Both PAF antagonists reduced the hypotension, the amount of hemoglobin in the gastric mucosa, and the PAF-induced gastric pathology. These results suggest that PAF receptors involved in PAF-induced neutrophil mobilization respond differently from PAF receptors in the gastrointestinal and cardiovascular systems.

Thienotriazolodiazepines as platelet-activating factor antagonists. Steric limitations for the substituent in position 2.

The preparations of thienotriazolodiazepines bearing a substituted ethynyl group at the 2-position, and the corresponding cis-olefins and fully saturated analogues are described. The compounds were evaluated as potential antagonists of platelet-activating factor (PAF) in in vitro and in vitro test models. The new thienotriazolodiazepines are compared with known related compounds such as WEB 2086 (compound 6) and the phenylethyl derivatives 27 and 28.

Triazolobenzo- and triazolothienodiazepines as potent antagonists of platelet activating factor.

A series of [1,2,4]triazolo[4,3-alpha][1,4]benzodiazepines bearing an ethynyl functionality at the 8-position and the isosteric thieno[3,2-f][1,2,4]triazolo[4,3-alpha][1,4]diazepines were prepared and evaluated as antagonists of platelet activating factor. The effects of substitution were explored in in vitro and in vivo test systems designed to measured PAF-antagonistic activity. Results are discussed and compared with previously published data. Many of the compounds had activity superior to WEB 2086, compound 1. In general, the thieno analogues exhibited better oral activity than the corresponding benzodiazepines. The duration of activity upon oral administration was modulated by the substitution on the acetylenic side chain. Compounds 71 and 81 were selected for further pharmacological evaluation as a result of their good oral potency and exceptionally long duration of action.

Only a minor fraction of plasma membrane-associated large T antigen in simian virus 40-transformed mouse tumor cells (mKSA) is exposed on the cell surface.

The bulk of simian virus 40 (SV40) large T antigen in SV40-infected and -transformed cells localizes within the cell nucleus, while a minor fraction specifically associates with the plasma membrane (PM) and is exposed on the cell surface. PM-associated large T seems to span the lipid bilayer but, on the other hand, does not display typical features of a transmembrane protein. To further characterize the postulated transmembrane orientation of large T, we asked whether all large T molecules associated with the plasma membrane indeed are exposed on the cell surface. We compared the amount of cell surface-exposed large T, determined on living cells by a sensitive 3H-protein A-binding assay and by external immunoprecipitation, with that of total PM-associated large T extracted from isolated PM. We demonstrate that in mKSA cells (SV40-transformed BALB/c mouse fibroblasts), total PM-associated large T accounted for a substantial portion (ca. 2%) of total cellular large T. However, only 0.1 to 0.2% of it could be detected on the cell surface. Thus, only a minor fraction of PM-associated large T (less than 10%) is exposed on the surface of these cells. Interior PM-associated large T is stably associated with the plasma membrane, while the small fraction of surface-exposed large T is rapidly released from the cell surface.

[Selective vitamin B 12 malabsorption in a 19-year-old patient]. / Selektive Vitamin-B12-Malabsorption bei einer 19jährigen Patientin.

Selective malabsorption of vitamin B12, or Imerslund-Gräsbeck disease, is a rare congenital condition. The normal ileal uptake of intrinsic-factor-bound vitamin B12 is deficient. Inheritance is autosomal recessive. Megaloblastic anemia generally appears in infancy and is usually accompanied by mild proteinuria. The case is presented of a 19-year-old woman with megaloblastic anemia due to selective vitamin B12 malabsorption. As far as we know this is the only patient in whom the disease appeared so late. Of special interest are also the marginally low Schilling tests of the patient's parents. Further conditions which may lead to vitamin B12 deficiency are also discussed. A hypothesis is put forward concerning the late appearance of the disease in this particular case. Pathophysiologic, nephrologic and genetic aspects of selective vitamin B12 malabsorption are briefly reviewed.

Ethological studies in animals and man, their use in psychiatry.

Ethology is concerned with the observation, description and measurement of the acts and postures which make up the behavioural repertoire of animals. Man too, exhibits analogous patterns of non-verbal behaviour, many of which serve social interactions. It is shown how ethological profiles of psychiatric patients can be constructed using the same methods as are used to analyse the social behaviour of rodents. It is argued that deficits in social behaviour are a key feature of the mentally ill patient and arise when flight, i. e. escape-oriented behaviour predominates. This notion is supported by an ethological study which shows that compared to healthy subjects, depressed patients exhibit fewer facial expressions and gestures which instigate or invite social interactions. These patterns serve to isolate the depressive patients from the group. With its emphasis upon objective analysis of behaviour, the ethological approach can provide a useful adjunct to conventional but largely subjective, clinical assessment schemes. It can also help to integrate findings in man and animals since in both, the behaviour is assessed in the same kind of units according to a common conceptual framework.