Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

Global, neuronal or β cell-specific deletion of inceptor improves glucose homeostasis in male mice with diet-induced obesity

Insulin resistance is an early complication of diet-induced obesity (DIO)1, potentially leading to hyperglycaemia and hyperinsulinaemia, accompanied by adaptive β cell hypertrophy and development of type 2 diabetes2. Insulin not only signals via the insulin receptor (INSR), but also promotes β cell survival, growth and function via the insulin-like growth factor 1 receptor (IGF1R)3-6. We recently identified the insulin inhibitory receptor (inceptor) as the key mediator of IGF1R and INSR desensitization7. But, although β cell-specific loss of inceptor improves β cell function in lean mice7, it warrants clarification whether inceptor signal inhibition also improves glycaemia under conditions of obesity. We assessed the glucometabolic effects of targeted inceptor deletion in either the brain or the pancreatic β cells under conditions of DIO in male mice. In the present study, we show that global and neuronal deletion of inceptor, as well as its adult-onset deletion in the β cells, improves glucose homeostasis by enhancing β cell health and function. Moreover, we demonstrate that inceptor-mediated improvement in glucose control does not depend on inceptor function in agouti-related protein-expressing or pro-opiomelanocortin neurons. Our data demonstrate that inceptor inhibition improves glucose homeostasis in mice with DIO, hence corroborating that inceptor is a crucial regulator of INSR and IGF1R signalling.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

Glucose-dependent insulinotropic polypeptide regulates body weight and food intake via GABAergic neurons in mice

The development of single-molecule co-agonists for the glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) is considered a breakthrough in the treatment of obesity and type 2 diabetes. But although GIPR-GLP-1R co-agonism decreases body weight with superior efficacy relative to GLP-1R agonism alone in preclinical1-3 and clinical studies4,5, the role of GIP in regulating energy metabolism remains enigmatic. Increasing evidence suggests that long-acting GIPR agonists act in the brain to decrease body weight through the inhibition of food intake3,6-8; however, the mechanisms and neuronal populations through which GIP affects metabolism remain to be identified. Here, we report that long-acting GIPR agonists and GIPR-GLP-1R co-agonists decrease body weight and food intake via inhibitory GABAergic neurons. We show that acyl-GIP decreases body weight and food intake in male diet-induced obese wild-type mice, but not in mice with deletion of Gipr in Vgat(also known as Slc32a1)-expressing GABAergic neurons (Vgat-Gipr knockout). Whereas the GIPR-GLP-1R co-agonist MAR709 leads, in male diet-induced obese wild-type mice, to greater weight loss and further inhibition of food intake relative to a pharmacokinetically matched acyl-GLP-1 control, this superiority over GLP-1 vanishes in Vgat-Gipr knockout mice. Our data demonstrate that long-acting GIPR agonists crucially depend on GIPR signaling in inhibitory GABAergic neurons to decrease body weight and food intake.

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb^{-1} and 257  pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

New C3H KitN824K/WT cancer mouse model develops late-onset malignant mammary tumors with high penetrance

Gastro-intestinal stromal tumors and acute myeloid leukemia induced by activating stem cell factor receptor tyrosine kinase (KIT) mutations are highly malignant. Less clear is the role of KIT mutations in the context of breast cancer. Treatment success of KIT-induced cancers is still unsatisfactory because of primary or secondary resistance to therapy. Mouse models offer essential platforms for studies on molecular disease mechanisms in basic cancer research. In the course of the Munich N-ethyl-N-nitrosourea (ENU) mutagenesis program a mouse line with inherited polycythemia was established. It carries a base-pair exchange in the Kit gene leading to an amino acid exchange at position 824 in the activation loop of KIT. This KIT variant corresponds to the N822K mutation found in human cancers, which is associated with imatinib-resistance. C3H Kit^N824K/WT mice develop hyperplasia of interstitial cells of Cajal and retention of ingesta in the cecum. In contrast to previous Kit-mutant models, we observe a benign course of gastrointestinal pathology associated with prolonged survival. Female mutants develop mammary carcinomas at late onset and subsequent lung metastasis. The disease model complements existing oncology research platforms. It allows for addressing the role of KIT mutations in breast cancer and identifying genetic and environmental modifiers of disease progression.

Leukotriene Antagonist S 872419 A for Early-Phase Treatment of Chemical Burn in the Rabbit Eye

S 872419 A, a specific receptor antagonist of peptide leukotrienes, was tested in the early-phase treatment of chemically burned eye (0.25 mol/l sodium hydroxide) of the rabbit. The drug was topically applied 5 times a day in a 1% solution, controls were the untreated opposite eye. Gross and microscopic investigations indicated that S 872419 A inhibits the inflammatory response of the chemically burned anterior eye segment. The parameters of healing considered (epithelial regeneration, corneal clouding and swelling, infiltration with polymorphonuclear leukocytes) suggest inhibition of lipoxygenase-mediated reactions in the tissue. PGF2 alpha levels were the same in aqueous humour of treated and untreated eyes. Further experiments with S 872419 A and other nonsteroidal drugs should improve the anti-inflammatory therapy of the chemically burned eye.

Cytochrome c oxidase subunit 4 isoform 2-knockout mice show reduced enzyme activity, airway hyporeactivity, and lung pathology

Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial electron transport chain. The purpose of this study was to analyze the function of lung-specific cytochrome c oxidase subunit 4 isoform 2 (COX4i2) in vitro and in COX4i2-knockout mice in vivo. COX was isolated from cow lung and liver as control and functionally analyzed. COX4i2-knockout mice were generated and the effect of the gene knockout was determined, including COX activity, tissue energy levels, noninvasive and invasive lung function, and lung pathology. These studies were complemented by a comprehensive functional screen performed at the German Mouse Clinic (Neuherberg, Germany). We show that isolated cow lung COX containing COX4i2 is about twice as active (88 and 102% increased activity in the presence of allosteric activator ADP and inhibitor ATP, respectively) as liver COX, which lacks COX4i2. In COX4i2-knockout mice, lung COX activity and cellular ATP levels were significantly reduced (-50 and -29%, respectively). Knockout mice showed decreased airway responsiveness (60% reduced P(enh) and 58% reduced airway resistance upon challenge with 25 and 100 mg methacholine, respectively), and they developed a lung pathology deteriorating with age that included the appearance of Charcot-Leyden crystals. In addition, there was an interesting sex-specific phenotype, in which the knockout females showed reduced lean mass (-12%), reduced total oxygen consumption rate (-8%), improved glucose tolerance, and reduced grip force (-14%) compared to wild-type females. Our data suggest that high activity lung COX is a central determinant of airway function and is required for maximal airway responsiveness and healthy lung function. Since airway constriction requires energy, we propose a model in which reduced tissue ATP levels explain protection from airway hyperresponsiveness, i.e., absence of COX4i2 leads to reduced lung COX activity and ATP levels, which results in impaired airway constriction and thus reduced airway responsiveness; long-term lung pathology develops in the knockout mice due to impairment of energy-costly lung maintenance processes; and therefore, we propose mitochondrial oxidative phosphorylation as a novel target for the treatment of respiratory diseases, such as asthma.

Origin of pancreatic ductal adenocarcinoma from atypical flat lesions: a comparative study in transgenic mice and human tissues

Pancreatic ductal adenocarcinoma (PDAC) and its precursor lesions, pancreatic intraepithelial neoplasia (PanIN), display a ductal phenotype. However, there is evidence in genetically defined mouse models for PDAC harbouring a mutated kras under the control of a pancreas-specific promoter that ductal cancer might arise in the centroacinar-acinar region, possibly through a process of acinar-ductal metaplasia (ADM). In order to further elucidate this model of PDAC development, an extensive expression analysis and molecular characterization of the putative and already established (PanIN) precursor lesions were performed in the Kras(G12D/+) ; Ptf1a-Cre(ex1/+) mouse model and in human tissues, focusing on lineage markers, developmental pathways, cell cycle regulators, apomucins, and stromal activation markers. The results of this study show that areas of ADM are very frequent in the murine and human pancreas and represent regions of increased proliferation of cells with precursor potential. Moreover, atypical flat lesions originating in areas of ADM are the most probable precursors of PDAC in the Kras(G12D/+); Ptf1a-Cre(ex1/+) mice and similar lesions were also found in the pancreas of three patients with a strong family history of PDAC. In conclusion, PDAC development in Kras(G12D/+); Ptf1a-Cre(ex1/+) mice starts from ADM and a similar process might also take place in patients with a strong family history of PDAC.

[Characterization of ENU-mutant mice. Animal models for human diseases using morphological and molecular methods]

Following sequencing of the human genome there are new challenges to decipher the knowledge concerning gene function and the role of gene interactions and pathways leading to disease. Mouse models have proven to be an ideal tool for this purpose. Point mutations induced by chemical mutagenesis by N-ethyl-N-nitrosourea (ENU) offer possibilities for the analysis of the phenotypic outcome of a single base pair exchange on the entire organism. The Munich ENU mouse mutagenesis project is part of the worldwide efforts to obtain mutations for each gene. The generation of new alleles or allelic series offers relevant insights into the relevance of single gene sections. Various mouse models for human diseases have been generated by a systematic large-scale genome-wide phenotyping screen in the last decade. This work illustrates how the implementation of the ENU mouse mutagenesis project with gene identification and parallel high-throughput screening is taking advantage of local cooperation with experienced phenotyping groups at the Helmholtz Zentrum München, leading to major advances in the functional analysis of the mammalian genome.

Missing-in-metastasis MIM/MTSS1 promotes actin assembly at intercellular junctions and is required for integrity of kidney epithelia

MIM/MTSS1 is a tissue-specific regulator of plasma membrane dynamics, whose altered expression levels have been linked to cancer metastasis. MIM deforms phosphoinositide-rich membranes through its I-BAR domain and interacts with actin monomers through its WH2 domain. Recent work proposed that MIM also potentiates Sonic hedgehog (Shh)-induced gene expression. Here, we generated MIM mutant mice and found that full-length MIM protein is dispensable for embryonic development. However, MIM-deficient mice displayed a severe urinary concentration defect caused by compromised integrity of kidney epithelia intercellular junctions, which led to bone abnormalities and end-stage renal failure. In cultured kidney epithelial (MDCK) cells, MIM displayed dynamic localization to adherens junctions, where it promoted Arp2/3-mediated actin filament assembly. This activity was dependent on the ability of MIM to interact with both membranes and actin monomers. Furthermore, results from the mouse model and cell culture experiments suggest that full-length MIM is not crucial for Shh signaling, at least during embryogenesis. Collectively, these data demonstrate that MIM modulates interplay between the actin cytoskeleton and plasma membrane to promote the maintenance of intercellular contacts in kidney epithelia.

Mouse phenotyping

Model organisms like the mouse are important tools to learn more about gene function in man. Within the last 20 years many mutant mouse lines have been generated by different methods such as ENU mutagenesis, constitutive and conditional knock-out approaches, knock-down, introduction of human genes, and knock-in techniques, thus creating models which mimic human conditions. Due to pleiotropic effects, one gene may have different functions in different organ systems or time points during development. Therefore mutant mouse lines have to be phenotyped comprehensively in a highly standardized manner to enable the detection of phenotypes which might otherwise remain hidden. The German Mouse Clinic (GMC) has been established at the Helmholtz Zentrum München as a phenotyping platform with open access to the scientific community (www.mousclinic.de; [1]). The GMC is a member of the EUMODIC consortium which created the European standard workflow EMPReSSslim for the systemic phenotyping of mouse models (http://www.eumodic.org/[2]).

Histopathological features of autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a chronic fibroinflammatory disease of the pancreas characterised by lymphoplasmacytic infiltrates, interstitial fibrosis, periductal inflammation and periphlebitis. Although first described more than four decades ago, it has not gained widespread attention until the 1990s when new insights into its aetiology, clinical presentation and management were discovered. Although nowadays widely accepted as a form of chronic pancreatitis, recent evidence suggests that AIP might not be confined to the pancreas but rather be an inflammatory pancreaticobiliary disease (autoimmune pancreatocholangitis, AIPC) with possible systemic involvement and association with other autoimmune disorders. This article reviews current concepts of AIP with special focus on the histopathological features of the disease.

[Perioperative conjunctival flora]

BACKGROUND

The conjunctival flora is of great interest for each case of intraocular operation preventing postoperative infections. Despite of negative cultures before the operation we investigated in a prospective randomized study perioperatively the bacterial situation of the conjunctiva in 105 patients.

MATERIAL AND METHODS

We took conjunctival swabs for microbiological examination from patient's eye operated on cataract or glaucoma, on the day of admission to the eye clinic and in the morning of the operating day. In addition, specimens were taken by nurses with Transwab MW-172 P before the local anaesthesia, disinfection of the conjunctiva and lids and application of eye drops, after these procedures by a research worker, at the end of the operation by the surgeon and two to three days after the operation by nurses with Transwab MW-172 P again. In 53 patients we collected lacrimal fluid to measure the lysozyme concentration.

RESULTS

Out of 686 conjunctival swabs we have found 126 (18.4%) positive cultures. Staphylococcus epidermidis had the highest incidence (109 = 86.5%) followed by Staphylococcus aureus (7 = 5.5%). Only in 28 eyes all conjunctival swabs, taken at different times, were negative. There was an increase of positive cultures from routine swabs on the day of admission from 13 (12.4%), to 33 (31.7%) in the swabs taken on the day of the operation in the morning. On the other side the positive cultures decreased then continuously before and after the preparation of the operation, at the end of the operation and during two to three days postoperatively. There was'nt any statistical correlation between the concentration of the lacrimal lysozyme and the rate of positive cultures.

CONCLUSION

The preoperative bacteriological diagnostic of the conjunctiva is important mainly for the prevention of postoperative endophthalmitis despite the transience and fluctuation of the conjunctival flora but also in case of endophthalmitis for rapid specific antibiotical therapy.

[Wyburn-Mason syndrome]

BACKGROUND

There are various malformations of retinal vessels. Some of them are associated with cerebral vascular anomalies.

MATERIALS AND METHODS

This report is given on a girl 6 years of age with a retinal racemose angioma.

RESULTS

The clinical examination showed a unilateral racemose angioma combined with retinachorioidal anastomosis and a hemifacial vascular malformation. We found teleangiectasia in this area. The ophthalmoscopy demonstrated a blurred border of optic disc on the right eye with forward protrusion of the disc about + 2.0 dioptres. Large racemose lesions may be localized to the optic nerve and may involve segmental areas of the macula. The ultrasound showed a papillary stasis with highly reflective structures. The ultrasonic patterns are interpreted as a cholesterosis or fibrovascular tissue. This findings may belong to the rare Wyburn-Mason syndrome. Acute neurological symptoms by similar lesions the midbrain and hemorrhages during extraction of teeth are reported in literature.

[Effect of tonometry and nasolacrimal duct irrigation on bacterial flora of the conjunctiva]

This study was undertaken to assess the influence of preoperative ophthalmological examinations on the microbial flora of the conjunctiva. For this purpose, 112 patients awaiting ocular surgery were included in the study. Conjunctival swabs for microbiological investigation were taken by nurses on the day of admission. In addition, specimens were taken before an ophthalmological examination, after applanation and impression tonometry, after irrigation of the lacrimal duct and 2 h after the end of all examinations. A last swab was taken preoperatively. Comparison of the microbiological results of the first two specimens only showed an agreement in 53% of the cases. The increase after tonometry and irrigation of the lacrimal duct in the number of swabs that were positive was not permanent. Swabs that were primarily germ-free and those that were mostly contaminated also showed strong bacterial fluctuation. Based on the present results, there is no strong evidence that the microorganisms found at the preoperative examinations correlate with a higher risk of postoperative infection. Disinfection of the conjunctival sac and the application of antibiotic drops are necessary on the day before the operation and immediately before it.

[Putschkowaskaja corneal protection]

BACKGROUND

Excessive cornea defects after chemical, thermal and microbiological damages respectively trophic disturbances often demand measures for conservation of the bulbus.

PATIENTS AND METHODS

In the time between 1969 and 1993 22 patients were provided with a "Keratoplasty according to Putschkowskaja": circular cut at the recipient eye 0.15 mm deep, trepan diameter 8.5 to 13 mm, without lamellar preparation, covering with a donor cornea of normal thickness by silk single sutures.

RESULTS

In 19 eyes the primary aim, the conservation of the bulbus, could be achieved. The complete transplant was mostly rejected after several months, only in two patients it healed by vascularisation. In one patient an abscess arose between recipient--cornea and transplant, which made explantation necessary. The histological examination of the transplant showed a purulent inflammation, swelling of the parenchym, partly absence of keratocytes and endothel cells, and a defect in the Bowman membrane.

CONCLUSION

The "Keratoplasty according to Putschkowskaja" can be useful as "living contact lens" besides other surgical measures for treatment (primary conservation of the bulbus) of excessive cornea defects. It seems that the existence of Bowman and Descemet membrane in the transplant prevents the decomposition of the donor cornea for a rather long time. By then the cornea defect has often healed leaving scars.

[Prenatal eyelid development in the hl-mouse--a hairless mutant of the colored wild mouse]

BACKGROUND

A decisive condition for the clarification of malformations and degenerations is knowledge of the pre- and postnatal development. Therefore investigations were undertaken to determine the plan and lay-out of the eye-lids in an hairloss mutant of mouse.

MATERIALS AND METHODS

Biomicroscopical and histological investigations were carried out in 51 hl-mice from the 10th day of gestation unto the birth. This particular mouse is a spontaneous hairloss mutant, in which corneal degenerations also occur.

RESULTS

On the 11th day of gestation the ectodermal dips may be distinguished, as well as the shoe-lace-like furrows around the eye-ball, which indicate the development of the eyelids. The upper and lower lid are formed by proliferation. The fusion of the eyelids is completed around the 16th day of gestation.

DISCUSSION

The eyelid development starts in mice between the 11th and 14th day of gestation. The fusion is completed on day 15-17. The morphogenesis of the eyelid development will be discussed.

[Diagnosis and therapy of chronic canaliculitis]

The chronic lacrimal canaliculitis is often overlooked and unsatisfactory treated. The purpose of this long-term study (1978-1991) is to call attention to special bacteriological signs and to give recommendations for proper treatment. 54 patients (39 females and 15 males) in age from 29 to 85 years (average age of 60 years) with a chronic lacrimal canaliculitis were evaluated. "Sulfur granules" were obtained from 32 patients and 54 specimens were collected from 44 patients and processed immediately for aerobic and anaerobic cultivation as well as microscopic investigation. Altogether 100 bacteria could be isolated: 56 anaerobes, 38 aerobes as well as 6 microaerophilic and capnophilic strains, respectively. Members of the genus Actinomyces were the most often isolated anaerobes. They could be detected in specimens of 15 patients by culture and in materials of 4 patients only by microscopic study. 42 from 50 patients were permanently cured by immediate treatment according to our operative procedure despite the splitted canaliculus. The most common cause of chronic lacrimal canaliculitis is a mixed infection. Despite the characteristic clinical symptoms the laboratory evaluation should be done to provide the diagnosis. The surgical procedure leads to a permanent functional healing in a high degree.

[The antiphlogistic effect of the ginkgolide BN 52 021 in the chemically burned rabbit eye]

BN 52 021, a specific antagonist of PAF receptors, was tested in the early-phase treatment of chemically burned eyes in 30 rabbits. The local application of BN 52 021 eyedrops-1% (water-soluble preparation, 5 times daily, in comparison with the other eye as a control) led to a visible anti-inflammatory effect (microscopically and macroscopically) of the chemically burned anterior eye segment. There was only a moderate increase of the concentration of PGF2 alpha after the chemical burn. The use of specific PAF antagonists seems to have a real chance for treatment of inflammatory reactions of the anterior eye segment. A combination with other mediator antagonists should be tested in further experiments.

[Peter's anomaly in animal experiments]

Histopathological examinations were performed in 193 embryos of mice; Peters's anomaly was found in 2 cases. The authors discuss various theories of formation of this developmental defect and oppose them their own formulation.

[Measurement of the power of artificial intraocular lenses]

Fifty five anterior chamber artificial lenses of the Hellgrebe model 2(35) and Fiodorov's (20) were verified from the angle of the power quoted by the producer. The measurement of the length of the frontal power were performed by means of a measurer 70 (Carl Zeiss, Jena, GDR) and by a specially designed plastic cuvette suitable for sterilization. The mean deviation amounted -1.42 dptr. for the Hellgrebe's 2 lens and 0.23 dptr. for Fiodorov's lens. The Hellgrebe type 2 lenses do not answer the international quality norms of tolerance +/- 0.25 dptr.

[Normogenesis of the cornea and its modification by cyclophosphamide in the animal experiment]

Animal experiments serving as models have hitherto been indispensable in order to explain pathogenetic processes in the development of malformations. The results presented here are contribution to studies on the normogenesis of the cornea in defined animal material (albino mice of Agnes Bluhm Jena-Halle stock). A single application of cyclophosphamide during embryogenesis caused inhibition malformations. Of these, different degrees of corneal hypoplasia and Peters' malformation are discussed in detail.

[Conservative treatment of glaucoma]

The author presents conservative treatment of glaucoma. Pharmacologic action of antiglaucoma drugs from group of mioties, and adrenergic blockers and other hypothension agents is discussed. Furthermore side effects of these drugs and their synergic action is presented. Personal experience connected with it is also discussed.

[Animal experiment and clinical studies of the use of anti-inflammatory agents in chemical burns of the eye]

In animal experiments and a clinical study of chemically burned eyes the anti-inflammatory effect of topically applied steroids and indomethacin (an inhibitor of cyclooxygenase) was investigated. Both the animal model and the clinical tests indicate the desirability of immediate local application of dexamethasone eyedrops 0.1% under careful biomicroscopic control of the burned eye and with local antibiotics. The use of topical steroids is a part of the authors' treatment for moderately severe and severe chemical eye burns (second degree, beginning third degree). However, this anti-inflammatory therapy cannot be recommended with indomethacin alone, because of the leukotriene-induced, increased infiltration of polymorphonuclear neutrophils and corneal ulceration.

Intracamerally applied prostacyclin raises the intraocular pressure in the rabbit

The effects of prostacyclin (PGI2) upon intraocular pressure and pupil size were examined in anaesthetized rabbits. Intracamerally applied PGI2 within the dosage range of 0.1 to 1.0/microgram led to an increase of the intraocular pressure (IOP) measured directly and continuously, and to a miosis. 6-oxo-PGF1 alpha, the product of hydrolysis of prostacyclin did not influence IOP or reaction of the pupil. Topical single doses of PGI2 of 4 to 80/micrograms on conjunctiva and cornea of the eye had no effect.

[Myelinization of the optic nerve in the albino mouse (the Agnes Bluhm Jena-Halle strain)]

Knowledge of normal differentiations is indispensable for interpreting developmental disturbances in animal experiments. Accordingly, the investigations described in the present paper were aimed at explaining the process of myelinization of the optic nerve in the domestic mouse breed Agnes Bluhm Jena-Halle. First signs of myelin sheath formation can be seen on the sixth and seventh day post partum. The myelin sheath grew considerably up to the 20th day of life; under light microscopic examination this process was seen to end on approximately the 30th day post partum. Electron-microscopic examination provided proof that myelinization is effected by the oligodendrocytes. This process of differentiation continues even in the adult animal, though on a very small scale.

[Prognosis of basal cell carcinoma of the eyelids in relation to histologic differentiation and thoroughness of resection]

As life expectancy increases the diagnosis and treatment of basal cell carcinoma of the lids is assuming ever greater importance. While there is still some debate as to whether conservative or surgical treatment is preferable, the emphasis in conservative treatment varies. Our own view is based on an analysis of 531 surgically treated patients. For histologic differentiation we used the data of Lever (1958). Considering that our recidivity rate was only 6.2%, we recommend primary surgical treatment. After localization of the tumor the inner canthus in particular should be kept under observation for recurrences. Histologic differentiation showed the sclerodermiform basal cell carcinoma to be especially dangerous.

[Intraocular metastases of primary malignant melanoma of the skin. Observation of 4 cases (author's transl)]

4 cases with intraocular metastases of primary skin melanoma are described. In 2 patients the diagnose could be confirmed by histological examination of the primary skin tumor and the involved eye. The poor prognosis of patients suffering from melanotic intraocular metastases indicates only a palliative ophthalmological treatment.

[Enzymatic studies in lenses of different breeds of mice (author's transl)]

Leucinaminopeptidase (LAP), lactatedehydrogenase (LDH) and glucose-6-phosphatdehydrogenase (GPDH) were analysed in the lenses of two different breeds of mice. Compared to the lenses of a control stock (Agnes Blum, Jena), in the healthy seeming, heterozygous mice the same activities of LAP, LDH, and GPDH were found. But in the breed with evident microphthalmos and cataract LDH was increased. Possible connections are discused.