Physiological features of Halomonas lionensis sp. nov., a novel bacterium isolated from a Mediterranean Sea sediment

A novel halophilic bacterium, strain RHS90(T), was isolated from marine sediments from the Gulf of Lions, in the Mediterranean Sea. Its metabolic and physiological characteristics were examined under various cultural conditions, including exposure to stressful ones (oligotrophy, high pressure and high concentrations of metals). Based on phylogenetic analysis of the 16S rRNA gene, the strain was found to belong to the genus Halomonas in the class Gammaproteobacteria. Its closest relatives are Halomonas axialensis and Halomonas meridiana (98% similarity). DNA-DNA hybridizations indicated that the novel isolate is genotypically distinct from these species. The DNA G + C content of the strain is 54.4 mol%. The main fatty acids (C18:1ω7c, 2-OH iso-C15:0, C16:0 and/or C19:0 cyclo ω8c), main polar lipids (diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified phosphoglycolipid) and major respiratory quinone (ubiquinone Q9) were determined. The novel isolate is heterotrophic, mesophilic, euryhaline (growth optimum ranging from 2 to 8% w/v NaCl) and is able to grow under stressful conditions. The strain accumulates poly-β-hydroxyalkanoates granules and compatible solutes. Based on genotypic, chemotaxonomic and phenotypic distinctiveness, this isolate is likely to represent a novel species, for which the name Halomonas lionensis is proposed. The type strain of H. lionensis is RHS90(T) (DSM 25632(T) = CIP 110370(T) = UBOCC 3186(T)).

Micromovement Evaluation of Original and Compatible Abutments at the Implant-abutment Interface

INTRODUCTION

Use of compatible abutments may increase micromovements between the abutments, and the inner part of the implant may increase the stress on marginal bone level. Also micromovement will change the volume of the inner space of the implant-abutment complex. The resulting pumping effect can transport even initially immobile microorganisms from the exterior to the interior and vice versa.

OBJECTIVES

The purpose of the study was to evaluate the mechanical comportment of OsseoSpeed™ Tx implants connected with original and compatible abutments in vitro under simulated clinical loading conditions.

MATERIALS AND METHODS

A total of 15 OsseoSpeed™ TX implants (4 × 11 mm) were used and divided into three groups (n = 5). Three types of abutments were used in the study; group I: Five original Ti Design™ abutments, group II: Five Natea™ abutments, and group III: Implanet™ abutments. Abutments used in groups II and III were all compatible with Astra Tech Implant System™. Implants were embedded into resin. Simulating the human masticatory cycle, the axial force vector was increased up to a defined maximum (25, 50, 75, 100, 125, 150, 175, and 200 N) and inclined 30° to the implant axis. A radiograph amplifier was used to convert the X-ray projection into a picture. The visual evaluation of the frames and the provided X-ray videos were evaluated for an existing microgap in width and length between the implant and the abutment.

RESULTS

An initial width gap was observed in groups II and III in four of the five samples with an average of 6.5 and 5 μm respectively. When the axial forces reach 75 N, only groups II and III demonstrated a gap width of 5.2 ± 3.63 and 4.8 ± 3.03 μm, and a gap length of 5.2 ± 3.63 and 94 ± 125.3 μm respectively. At 200 N, group I showed a gap width of 8.4 ± 1.67 μm and a gap length of 187.6 ± 43.6 μm, while groups II and III showed a gap width of 12.4 ± 3.29 and 22.8 ± 5.76 μm, and a gap length of 387.2 ± 84.36 and 641.2 ± 122.6 μm respectively.

CONCLUSION

Within the limitations of this study and under the parameters used and from the resulting data collected, we can presume that the use of compatible components leads to significant micromovement when compared with the use of original ones.

CLINICAL SIGNIFICANCE

The use of compatible prosthetic components with original implants showed significant micromovements when compared with the use of abutment and implant from the same manufacturer. Clinically, the micromovements when associated with leakage leads to bone loss around the neck of the implant and later to peri-implantitis.

A pragmatic approach to the analysis of a combination formulation

The aim of the paper was to formulate a combined oral dosage form of rosuvastatin calcium and amlodipine besylate and to develop and validate an analytical method to be adopted for both routine quality control assay and in vitro dissolution studies of the formulation.

The proposed combination formulation has shown compatibility with the chosen excipients, verified through FT-IR study. A novel gradient RP-HPLC method was developed and validated according to the ICH guideline which was found to be suitable for the simultaneous estimation of rosuvastatin calcium and amlodipine besylate from the formulation. The retention time of 2.7 and 6.08 min allows the analysis of large amount of samples with less mobile phase which makes the method economic. The dissolution profiles of both the drugs in different dissolution medium were encouraging which makes the combination formulation of rosuvastatin calcium and amlodipine besylate superior and effective in achieving patient compliance.

Some fixed point results of generalized ( ϕ , ψ ) -contractive mappings in ordered b-metric spaces

OBJECTIVES

The aim of this paper is to establish some fixed point, coincidence point and, coupled coincidence and coupled common fixed point results for generalized( ϕ , ψ ) -contractive mappings in partially ordered b-metric spaces. Our results generalize, extend and unify most of the fundamental metrical fixed point theorems in the existing literature. Few examples are illustrated to justify our results.

RESULT

The existence and uniqueness theorems for a fixed point and coincidence point, coupled coincidence point and coupled common fixed points for two mappings satisfying generalized( ϕ , ψ ) -contractive conditions in complete partially ordered b-metric spaces are proved. These results generalize several comparable results in the existing literature.

Design of Experiment (DOE) Utilization to Develop a Simple and Robust Reversed-Phase HPLC Technique for Related Substances' Estimation of Omeprazole Formulations

A simple, fast, and sensitive reversed-phase HPLC method with UV detection was developed for the quantitation of omeprazole and its eleven related compounds (impurities) in pharmaceutical formulation using the Thermo Accucore C–18 (50 mm × 4.6 mm, 2.6 μm) column. The separation among all the compounds was achieved with a flow rate of 0.8 mL min⁻¹ employing a gradient program of mobile phase A [0.08 M glycine buffer pH 9.0: acetonitrile; 95:05 (v/v)] and mobile phase B [acetonitrile: methanol; 65:35 (v/v)]. The chromatographic detection was carried out at a wavelength of 305 nm. The method was validated for specificity, linearity, and recovery. The huskiness of the method was determined prior to validation using the Design of Experiments (DOE). The ANOVA analysis of DOE with a 95% confidence interval (CI) confirmed the buffer pH of mobile phase A (p <0.0001) and column temperature (p<0.0001) as significant Critical Method Parameters (CMPs).

Outcomes of keratolimbal allograft from ABO compatible donors for severe bilateral limbal stem cell deficiency

PURPOSE

To report outcomes of keratolimbal allograft (KLAL) compatible for both human leukocyte (HLA) and/or blood type using oral prednisone, mycophenolate, and tacrolimus, with basiliximab if panel reactive antibodies (PRA) are present. Intravenous immunoglobulin (IVIG) was used post-operatively if donor-specific anti-HLA antibodies (DSA) were present.

METHODS

Retrospective interventional series of consecutive patients with KLAL for limbal stem cell deficiency (LSCD) from HLA and/or blood type compatible deceased donors with a minimum follow-up time of 12 months. Main outcome measures were ocular surface stability, visual acuity and systemic immunosuppression (SI) adverse events.

RESULTS

Eight eyes of eight patients with mean age of 48.6 ± 10.1 years (range 34-65 years) were included. Mean follow-up time was 37.3 ± 22.7 months (range 12-71 months) following KLAL; four (50%) had combined LR-CLAL surgery. The etiologies of LSCD were Stevens-Johnson Syndrome (n = 4/8), aniridia (n = 2/8), chemical injury (n = 1/8) and atopic eye disease (n = 1/8). All patients had PRA present and received basiliximab infusions. 5/8 patients received IVIG based on DSA identified pre-operatively. At last follow-up, 7 eyes (87.5%) had a stable ocular surface; 1 eye (12.5%) developed failure and had keratoprosthesis implantation. There was a significant improvement in visual acuity from 1.65 ± 0.48 to 0.68 ± 0.34 logMAR (p = 0.01). SI was tolerated well with minimal adverse events.

CONCLUSIONS

Preliminary outcomes of KLAL with ABO compatible tissue using the Cincinnati protocol, preoperative basiliximab (when PRA present) and post-operative IVIG (when DSA present) are encouraging. This protocol may allow for utilization of deceased donor tissue with results approximating those of living donor tissue transplanted for severe bilateral LSCD.

Ecosystem services in conservation planning: Assessing compatible vs. incompatible conservation

The compatible conservation of ecosystem services (ES) refers to the sustainable development of a region and the multiple dimensions of the region population's well-being. Applying the ES relationship to systematic conservation planning (SCP) can help determine the protection priorities associated with ES and support good zoning decisions. This study uses Nanchang, China as a case study to construct a multi-scenario ES protection scheme. This includes evaluating the spatial distribution characteristics of four core ES, and the ES relationships in the subregion in Nanchang. The ES relationship is then used to construct three ES conservation scenarios (synergetic, trade-off and incompatible), and the SCP tool is used for zoning. The results show the following. First, the incompatible scenario prioritizes the conservation of supporting services and provisioning services, which support ecological protection and cultivated land security. Second, given a land management and control threshold, the management zones can be compatible with a large proportion of secondary services in the synergetic scenario (22%). Fewer secondary services are compatible under the trade-off scenario (8%). As the compatible secondary service targets increase, each management zone area experiences a nonlinear change. The spatial change is more stable in the synergetic scenario compared to the trade-off scenario, and the space of management zone becomes discrete under the trade-off scenario. Third, the compatibility process has a feedback effect on the ES relationship. Compared with the trade-off scenario, compatible synergetic services are more stable with respect to changes in the ES relationship. Constructing ecological buffer zones takes up cultivated land, decreasing the synergy between carbon sequestration services and food production services. However, ecological buffer zones should play a role in certain areas. The compatibility of increased food production services and habitat services in priority conservation and controlled development zones enhance ES trade-offs. An increase in cultural services is compatible with carbon sequestration services in the ecological buffer zone. This changes the relationship between ES, from having a weak trade-off to having a weak synergy. Creating a compatible ES is a spatial trade-off process; these synergies and trade-offs should be considered in spatial planning. An appropriate proportion of ES should be allocated to each zone, to increase the coordinated management of the urban-rural ecology.

A Toolkit for Teasing Apart the Early Stages of Pollen-Stigma Interactions in Arabidopsis thaliana

In hermaphroditic flowering plants, the female pistil serves as the main gatekeeper of mate acceptance as several mechanisms are present to prevent fertilization by unsuitable pollen. The characteristic Brassicaceae dry stigma at the top of pistil represents the first layer that requires pollen recognition to elicit appropriate physiological responses from the pistil. Successful pollen-stigma interactions then lead to pollen hydration, pollen germination, and pollen tube entry into the stigmatic surface. To assess these early stages in detail, our lab has used three experimental procedures to quantitatively and qualitatively characterize the outcome of compatible pollen-stigma interactions that would ultimately lead to the successful fertilization. These assays are also useful for assessing self-incompatible pollinations and mutations that affect these pathways. The model organism, Arabidopsis thaliana, offers an excellent platform for these investigations as loss-of-function or gain-of-function mutants can be easily generated using CRISPR/Cas9 technology, existing T-DNA insertion mutant collections, and heterologous expression constructs, respectively. Here, we provide a detailed description of the methods for these inexpensive assays that can be reliably used to assess pollen-stigma interactions and used to identify new players regulating these processes.

Accuracy of Original vs. Non-original Abutments Using Various Connection Geometries for Single Unit Restorations: A Systematic Review

PURPOSE

To ascertain whether the compatibility of non-original abutments (NOAs) with dental implants is influenced by the type of implant connection i.e. internal or external, and whether certain combinations of componentry may be as compatible as the original components.

METHODS

A structured literature search was conducted using 3 electronic databases (MEDLINE®, The Cochrane Library, and Web of Science Core Collection) for studies reporting on the use of non-original abutments published between 1995 and 2020. This was supplemented with hand searching in relevant journals and references, as well as searching grey literature. Relevant studies were selected according to specific inclusion criteria. Data was collected for the following parameters: precision of fit, microleakage, micromorphological differences, micromotion, rotational misfit, screw loosening, maximum load capacity, fracture resistance, tensile strength, compressive strength and in-vivo implant and prosthesis outcomes.

RESULTS

The electronic searching and hand search yielded titles and abstracts of 5617 studies following de-duplication; 40 studies were finally selected. Overall, original abutments showed better precision of fit, ability to resist microleakage, prevention of rotational misfit and micromotion, and fatigue strength compared with non-original abutments. Some non-original abutments on external connections were comparable with original abutments in terms of precision of fit and resistance to screw loosening and may be associated with less catastrophic failures than those on internal connections.

CONCLUSION

Original abutments present more predictable outcomes than non-original abutments with regards to the parameters investigated. However, it seems that external connections can provide some level of compatibility in terms of precision of fit and may also exhibit less catastrophic failures than NOAs on internal connections. This may be due to increased rotational freedom external connections provide. There is a lack of information regarding the influence of connection geometry on many aspects of compatibility and therefore the current clinical recommendation should be to use original abutments. More laboratory studies comparing non-original abutments on different implant connections are required. In addition, there is a need for long-term in vivo studies providing data on the clinical performance of non-original abutments. This article is protected by copyright. All rights reserved.