The neutrophil-specific antigen NB1 is expressed by neutrophils from 97% of healthy adults. However, membrane expression of this molecule is unique in that it is found on only a subpopulation of neutrophils present in NB1-positive adults. We have investigated the ontogeny of NB1 antigen expression by haematopoietic progenitor cells to determine the stage and pattern of antigen expression during granulocytic cell differentiation. In addition, we examined whether the ontogeny and frequency of granulocytic cells expressing the NB1 antigen might vary in subjects according to age. A monoclonal antibody (MoAb) specific for NB1 (1B5) and flow cytometry was used to assess the frequency and characteristics of the NB1-positive cells found in umbilical cord blood (n = 11), children (n = 37), healthy adults (n = 46) and patients with chronic myelogenous leukaemia (n = 8). We also used flow cytometry to isolate NB1-positive and NB1-negative bone marrow and peripheral blood cells from various tissue sources. The separated subpopulations were then analysed by Wright stain and light microscopy. The size of the NB1-positive neutrophil subpopulation in 46 healthy adults (56 +/- 19%) was identical to that found for neutrophils from 36 children ranging in age from 8 months to 18 years (56 +/- 11%). In contrast, expression of the NB1 antigen by the neutrophils present in umbilical cord blood (91 +/- 3%, n = 11) was significantly greater than that in adults (P < 0.002) or children (P < 0.002). We also examined the size of the NB1-positive subpopulation among neutrophils from eight patients with chronic myelogenous leukaemia (CML). The NB1-positive subset in CML subjects (29.5 +/- 22.4%) was significantly less that in healthy adults (P < 0.02) or children (P < 0.02). Marrow cells from eight adults were similarly separated and analysed. We found that 69 +/- 17% of segmented and band forms of neutrophils, 70 +/- 2% of metamyelocytes and 61 +/- 23% of myelocytes were NB1-positive. In fetal bone marrow, 86 +/- 9% of the segmented and band forms, 82 +/- 10% of the metamyelocytes and 3 +/- 4% of myelocytes were NB1-positive. In conclusion, neutrophil-specific antigen NB1 is first expressed at the myelocyte stage of myeloid differentiation. In adult bone marrow, the percentages of myelocytes, metamyelocytes and segmented or band cells that expressed this antigen were similar and comparable in magnitude to the frequency of NB1-positive neutrophils found in the circulation. Although the size of the NB1-positive neutrophil subpopulation was the same in healthy adults and children, it was significantly increased in umbilical cord blood, and in fetal marrow cells.

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AimThe aim of this study is to report the mechanism of XEN migration and its management.BackgroundOver the past decade, new less invasive surgical approaches for glaucoma have been devised and carried out successfully. One such technique is the use of the XEN gel stent. We present a rare and relatively unknown complication of XEN migration and present in detail the likely mechanism by which this occurs, and its subsequent management.Case descriptionA 73-year-old male with primary angle closure on maximal medical treatment presented with an intraocular pressure of 30 mm Hg in the left eye. The visual acuity was 6/5, iridocorneal angles were open in all four quadrants, and the cup disc ratio was 0.4. As phacoemulsification alone was unlikely to adequately lower intraocular pressures, the patient underwent combined phacoemulsification and XEN implantation. Although the patient had a good postoperative result with pressures lowered to 11 mm Hg, 4 months after the operation, the XEN was found to have migrated 4 mm into the anterior chamber, associated with a low-grade uveitis. The patient subsequently had the XEN explanted a new XEN inserted. Pressures lowered 1 month postoperatively to 14 mm Hg.ConclusionXEN migration is likely due to a combination of mechanical and frictional forces. If the XEN is positioned such that more than 2 mm is in the subconjunctival space, the XEN is likely to be angled upward and, therefore, be more susceptible to these forces and undergo migration.Clinical significanceIt is essential that XEN implants are correctly sited and that this is confirmed intraoperatively to prevent the need for further procedures.How to cite this articleAli ZC, Khoo DI, et al. Migration of XEN45 Implant: Findings, Mechanism, and Management. J Curr Glaucoma Pract 2019;13(2):79–81.

Immunological and biochemical assays were developed for screening for resistance to Diaporthe toxica in individual plants of narrow‐leafed lupins (Lupinus angustifolius). The former was an enzyme‐linked immunosorbent assay (ELISA) for measuring phomopsin mycotoxins and the latter gave an estimation of glucoseamine in infected stem pieces. Stems of L. angustifolius seedlings were inoculated with conidia from D. toxica cultures and, as expected with this latent disease, remained symptomless for 21 days after inoculation. At this time, phomopsins were measured in excised stems that had been incubated for 6 or 8 days to allow mycelial growth from latent infection structures, thereby increasing the phomopsins to detectable levels in individual plants. The estimation of glucoseamine was carried out on the same stems that had been assayed for phomopsins. The method was based on the alkaline deacetylation of chitin to chitosan, the glucoseamine residues of which are de‐aminated with nitrous acid, yielding an aldehyde which is determined colorimetrically. At six days after excision, both tests clearly distinguished the very resistant, resistant, intermediate and susceptible lines and they may be useful in large‐scale resistance screening in lupin breeding programmes. The ELISA of phomopsins is easier to use and would be particularly useful in the elimination of susceptible plants and those plants expressing intermediate levels of resistance during early generations of the breeding programme.

This study proposes a novel control design of Unified Power Quality Conditioner (UPQC). This design is enabled by a control framework that employs Genetic Algorithm which determines optimum points and angle for filtering and Space Vector Pulse Width Modulation Technique (SVPWM) to offer significant flexibility to optimize waveform. In addition the same framework integrates the major functions of the UPQC with ease to unify the treatments of several power quality problems including system harmonics in the supply voltage and load current, sags/swells in the supply voltage, variations in the load demands and poor power factor at the supply side. Simulation studies on a three phase power distribution system are used to verify the performance and implementation of this control design with the UPQC.