Narrow-Band Microwave Filter Using High-Q Groove Gap Waveguide Resonators With Manufacturing Flexibility and No Sidewalls

This paper presents a new type of narrow band filter with good electrical performance and manufacturing flexibility, based on the newly introduced groove gap waveguide technology. The designed third and fifth-order filters work at Ku band with 1% fractional bandwidth. These filter structures are manufactured with an allowable gap between two metal blocks, in such a way that there is no requirement for electrical contact and alignment between the blocks. This is a major manufacturing advantage compared to normal rectangular waveguide filters. The measured results of the manufactured filters show reasonably good agreement with the full-wave simulated results, without any tuning or adjustments

Numerical Prepackaging with PMC Lid - Efficient and Simple Design Procedure for Microstrip Circuits Including the Packaging

The paper presents an efficient method for the design of printed microstrip circuit with packaging in mind, referred to as numerical prepackaging with a perfectly magnetic conductive (PMC) lid. The method comprises making the design including the packaging from the start by using a PMC lid, rather than first designing the open-aired circuit; and thereafter, considering the packaging effect and the often required retuning of the circuits themselves. The advantage is that no parallel plate modes can propagate between the perfect electric conductor (PEC) ground plane and the PMC lid plate if the spacing is smaller than an effective quarter of wavelength. This provides a limited computational volume so that the computation time is significantly reduced in the case of the finite element method (FEM) or the finite difference time domain method (FDTD). By using numerical packaging with PMC lid, the ideal PMC lid has to be realized afterwards e.g. by using a lid of nails, which is a minor task as compared to existing approaches

sCR1sLeX reduces lung allograft ischemia-reperfusion injury but does not ameliorate acute rejection

Background: Combined inhibition of complement and leukocyte adhesion by sCR1sLeX reduces lung allograft dysfunction up to 24 h. In the present study its effect on graft function and acute rejection was evaluated up to 5 days after experimental transplantation. Methods: Orthotopic single left lung transplantation was performed in 35 male rats (Brown Norway to Fischer 344) after a total ischemic time of 20 h. Two groups were assessed after 1, 3, and 5 days post-transplant, respectively (n=5 per group and time point): controls vs. recipients which received 10 mg/kg sCR1sLeX 15 min prior to reperfusion. In addition, five animals received 10 mg/kg per day sCR1sLeX for 5 days. For blood gas analysis of the graft, the contralateral lung was occluded for 5 min to assess graft function. Lung grafts were flushed, and histological grading was performed in blinded fashion according to the International Society for Heart and Lung Transplantation criteria. Results: Graft PaO2 in recipients treated with sCR1sLeX was superior on day 1 (383±118 vs. 56±15 mmHg; P≪0.0001) and day 3 (446±48 vs. 231±108 mmHg; P≪0.0001). Five days after transplantation, no difference in PaO2 was found (61±28 vs. 83±31 mmHg; P=0.59). Repeated treatment with sCR1sLeX for 5 days did not improve PaO2 (64±5 mmHg; P=0.65 vs. control; P=0.93 vs. sCR1sLeX). At any time point, there was no difference in the degree of rejection between groups. Conclusions: In this model sCR1sLeX provided marked improvement of graft function up to 3 days, but inhibition of both complement system and selectin dependent leukocyte adhesion failed to protect against acute rejectio

Bed of Springs for Packaging of Microstrip Circuits in the Microwave Frequency Range

After the use of the bed of nails for removing cavity modes in microstrip circuit packages, we propose herein a new version of this periodic structure, based on helices (springs) instead of nails. This new structure, named bed of springs, is much more compact, and this allows its use at low frequencies where the bed of nails is not suitable as it is too bulky due to the required height of the nails (pins). The bandwidth of the proposed structure turns out to be similar to the case of bed of nails. Parametric studies are presented as a design tool and a demonstrator is manufactured and measured

Donor and recipient treatment with the Lazaroid U-74006F do not improve post-transplant lung function in swine

Objective: U-74006F is the only Lazaroid which is currently in clinical use. A number of experimental studies demonstrate that Lazaroids reduce ischemia/reperfusion injury in various organ systems. We evaluated the effect of U-74006F on reperfusion injury in a large animal model of lung allo-transplantation. Methods: Two different treatment modalities were evaluated and compared with corresponding control groups. Unilateral left lung transplantation was performed in 21 weight-matched pigs (24-31 kg). Donor lungs were flushed with 1.5 l cold (1°C) LPD solution and preserved for 20 h. In group I (n=5), donor animals were pretreated with U-74006F (10 mg/kg i.v.) 20 min before harvest. In addition U-74006F was added to the flush solution (10 mg/l). In group III (n=6), the Lazaroid was given to the donor before flush and to the recipient before reperfusion (3 mg/kg i.v.). Group II and IV (n=5) served as control. One hour after reperfusion, the recipient contralateral right pulmonary artery and bronchus were ligated to assess graft function only. Extravascular lung water index (EVLWI), mean pulmonary artery pressure, cardiac output, and gas exchange were assessed during a 5 h observation period. Lipid peroxidation (TBARS) and neutrophil migration (MPO activity) were measured at the end of the assessment in lung allograft tissue. Results: A significant change of TBARS concentration was shown in group III (group III 78.7±4.6 pmol/g vs. group IV 120.8±7.2 pmol/g (P=0.0065) normal lung tissue 41.3±4.2 pmol/g). MPO activity was reduced in group III 3.74±0.25 δOD/mg per min vs. group IV 4.97±0.26 δOD/mg per min (P=0.027), normal lung tissue 1.04±0.27 δOD/mg per min). Pulmonary hemodynamics and gas exchange after reperfusion did not differ between groups. In group I and III, a tendency towards a reduced EVLWI was noted. Conclusion: We conclude that combined treatment of donor and recipient with U-74006F reduces free radical mediated injury in the allograft. However, this intervention did not result in a significant reduction of post-transplant lung edema or improvement of pulmonary hemodynamics. Donor pretreatment alone did not improve lung allograft reperfusion injury. These results indicate that the benefit of U-74006F is too small to consider clinical application in lung transplantatio

Effect of a short period of warm ischemia after cold preservation on reperfusion injury in lung allotransplantation

Objective: A short period of warm ischemia during lung allograft implantation is inevitable. We studied the effect of 2 h of warm ischemia before implantation after 18 h of cold preservation on reperfusion edema and pulmonary hemodynamics in a large animal model. Methods: Left lung transplantation was performed in ten weight-matched pigs (25-31 kg). Donor lungs were flushed with 1.5 l cold (1°C) LPD solution and preserved for 20 h. In Group I (n=5) the grafts were preserved for 20 h at 1°C and topically cooled with ice slush during implantation until reperfusion. In Group II (n=5) lungs were stored at 1°C for 18 h followed by 2 h preservation at room temperature (20°C). Topical cooling was not used during implantation. At 1 h after reperfusion the recipient contralateral right pulmonary artery and bronchus were ligated to assess graft function only. Extravascular lung water index (EVLWI), intrathoracic blood volume (ITBV), mean pulmonary artery pressure (PAP) and cardiac output (CO) were assessed during a 4 h observation period. Quantitative myeloperoxidase (MPO) activity and thiobarbituric acid-reactive substance (TBARS) levels as an indicator for lipid peroxidation were determined in allograft tissue samples taken 5 h after reperfusion. Results: In Group II a tendency to improved pulmonary vascular resistance and cardiac output was noted. Surprisingly, lung edema, assessed by EVLWI, did not increase in animals with warm ischemia. Even a tendency to a reduced EVLWI was noted. However, differences between groups did not reach statistical significance. Gas exchange did not differ statistically significant between groups. Conclusion: Our results indicate that a short period of warm ischemia before reperfusion does not lead to increased pulmonary edema. In animals with a short period of warm ischemia before reperfusion, even a tendency to reduced posttransplant lung reperfusion injury was noted. In this model, topical graft cooling during lung implantation did not improve posttransplant graft functio

Synergistic effect of low dose Cyclosporine A and human interleukin 10 overexpression on acute rejection in rat lung allotransplantation

Objective: Electroporation mediated transfer of plasmid DNA into peripheral muscle results in high transfection efficiency. The aim of this study was to investigate the effect of gene transfer of human IL-10 (hIL-10) into the tibialis anterior muscle (MTA) in combination with low dose Cyclosporine A (CsA) on acute rejection of lung allografts in the rat. Methods: Lung allotransplantation was performed from male BN donor to male Fisher F344 rats. Gene transfer was achieved by intramuscular injection into the MTA of the recipient followed by electroporation (4×20ms impulses at 200V/cm) 24h prior to the transplantation. Group A (n=5) received CsA (2.5mg/kg bw ip) for 5 days post-transplant and group B (n=5) 2.5μg of PCIK hIL-10 (plasmid expression vector containing human CMV immediate early gene promoter and enhancer) and a low dose CsA (2.5mg/kg bw i.p.). Graft function was assessed by blood gas at day 5 after exclusion of the native lung. Animals were sacrificed and blood was drawn to measure serum hIL-10 levels (ELISA) and tissue was sampled for histological grading of rejection. Results: Local expression of hIL-10 was confirmed at the mRNA level by in situ hybridization. All group A control animals showed severe signs of rejection. At day 5 all grafts in group B showed good gas exchange mean PaO2 233±123mmHg, vs 44±8mmHg in group A. Histological examination revealed moderate to severe rejection in all animals in group A (IIIB, ISHLT) in contrast to low moderate rejection in group B (II-IIIA). hIL-10 serum levels on day 5 were 14±7pg/ml in group B vs. 0 in group A. Conclusions: Electroporation mediated hIL-10 overexpression in a peripheral muscle of the recipient in combination with low dose CsA reduces acute rejection in this model of rat lung allotransplantatio

Studies on the antidiarrhoeal, antimicrobial and cytotoxic activities of ethanol-extracted leaves of yellow oleander (Thevetia peruviana)

This study screened the antidiarrhoeal, antimicrobial and cytotoxic effects of ethanol-extracted leaves of yellow oleander (Thevetia peruviana). The extract was tested against castor oil-induced diarrhoea in a model of albino rats and showed significant antidiarrhoeal activity (P<0.01). Disc diffusion technique was used to test the in vitro antibacterial activities of the extract and exhibited poor antibacterial activities against both Gram positive and Gram negative bacteria (mainly Bacillus sp). Ethanol-extracted leaves of yellow oleander showed narrow zone of inhibition in the bacterial lawns of Shigella flexineri, Salmonella typhi, Klebsiella sp, Staphylococcus aureus and Shigella sonnei. Cytotoxicty was determined against brine shrimp nauplii and LC50 of the plant extract was determined as 627.21μg/ml. The wide range of LC50 value denotes the safety effect of the extract

Survival and graft function in a large animal lung transplant model after 30 h preservation and substitution of the nitric oxide pathway

Objective: Substitution of the nitric oxide- (NO-) pathway improves early graft function following lung transplantation. We previously demonstrated that 8-Br-cGMP (second messenger of NO) to the flush solution and tetrahydrobiopterin (BH4, coenzyme of NO synthase) given as additive during reperfusion improve post-transplant graft function. In the present study, the combined treatment with 8-Br-cGMP and BH4 was evaluated. Methods: Unilateral left lung transplantation was performed in weight matched outbred pigs (24-31kg). In group I, grafts were preserved for 30h (n=5). 8-Br-cGMP (1mg/kg) was added to the flush solution (Perfadex™, 1.5l, 1°C) and BH4 (10mg/kg/h) was given to the recipient for 5h after reperfusion. In group II, lungs were transplanted after a preservation time of 30h (n=3) and prostaglandin E1 (250g) was given into the pulmonary artery (PA) prior to flush. In all recipients 1h after reperfusion the contralateral right PA and bronchus were ligated to assess graft function only. Survival time after reperfusion, extravascular lung water index (EVLWI), hemodynamic variables, and gas exchange (PaO2) were assessed during a 12h observation period. Results: All recipients in group I survived the 12h assessment, whereas none of the group II animals survived more than 4h after reperfusion with a rapid increase of EVLWI up to 24.8±6.7ml/kg. In contrast, in group I EVLWI reached up to 8.9±1.5ml/kg and returned to nearly normal levels at 12h (6.1±0.8ml/kg). In two animals of group I the gas exchange deteriorated slightly. The other three animals showed normal arterial oxygenation over the entire observation time. Conclusion: Our data indicate that the combined substitution of the NO pathway during preservation and reperfusion reduces ischemia/reperfusion injury substantially and that this treatment even allows lung transplantation after 30h preservation in this mode

First-in-Man Phase I Trial of the Selective MET Inhibitor Tepotinib in Patients with Advanced Solid Tumors.

PurposeTepotinib is an oral, potent, highly selective MET inhibitor. This first-in-man phase I trial investigated the MTD of tepotinib to determine the recommended phase II dose (RP2D).Patients and methodsPatients received tepotinib orally according to one of three dose escalation regimens (R) on a 21-day cycle: R1, 30-400 mg once daily for 14 days; R2, 30-315 mg once daily 3 times/week; or R3, 300-1,400 mg once daily. After two cycles, treatment could continue in patients with stable disease until disease progression or unacceptable toxicity. The primary endpoint was incidence of dose-limiting toxicity (DLT) and treatment-emergent adverse events (TEAE). Secondary endpoints included safety, tolerability, pharmacokinetics, pharmacodynamics, and antitumor effects.ResultsOne hundred and forty-nine patients received tepotinib (R1: n = 42; R2: n = 45; R3: n = 62). Although six patients reported DLTs [one patient in R1 (115 mg), three patients in R2 (60, 100, 130 mg), two patients in R3 (1,000, 1,400 mg)], the MTD was not reached at the highest tested dose of 1,400 mg daily. The RP2D of tepotinib was established as 500 mg once daily, supported by translational modeling data as sufficient to achieve ≥95% MET inhibition in ≥90% of patients. Treatment-related TEAEs were mostly grade 1 or 2 fatigue, peripheral edema, decreased appetite, nausea, vomiting, and lipase increase. The best overall response in R3 was partial response in two patients, both with MET overexpression.ConclusionsTepotinib was well tolerated with clinical activity in MET-dysregulated tumors. The RP2D of tepotinib was established as 500 mg once daily. MET abnormalities can drive tumorigenesis. This first-in-man trial demonstrated that the potent, highly selective MET inhibitor tepotinib can reduce or stabilize tumor burden and is well tolerated at doses up to 1,400 mg once daily. An RP2D of 500 mg once daily, as determined from translational modeling and simulation integrating human population pharmacokinetic and pharmacodynamic data in tumor biopsies, is being used in ongoing clinical trials