scholarly journals Effect of increasing dose level of a novel consensus bacterial 6-phytase variant on phytate degradation in broilers fed diets containing varied phytate levels

Author(s):  
Y. Dersjant-li ◽  
T. Christensen ◽  
S. Knudsen ◽  
A. Bello ◽  
M Toghyani ◽  
...  
Author(s):  
D. E. Philpott ◽  
W. Sapp ◽  
C. Williams ◽  
Joann Stevenson ◽  
S. Black

The response of spermatogonial cells to X-irradiation is well documented. It has been shown that there is a radiation resistent stem cell (As) which, after irradiation, replenishes the seminiferous epithelium. Most investigations in this area have dealt with radiation dosages of 100R or more. This study was undertaken to observe cellular responses at doses less than 100R of X-irradiation utilizing a system in which the tissue can be used for light and electron microscopy.Brown B6D2F1 mice aged 16 weeks were exposed to X-irradiation (225KeV; 15mA; filter 0.35 Cu; 50-60 R/min). Four mice were irradiated at each dose level between 1 and 100 rads. Testes were removed 3 days post-irradiation, fixed, and embedded. Sections were cut at 2 microns for light microscopy. After staining, surviving spermatogonia were identified and counted in tubule cross sections. The surviving fraction of spermatogonia compared to control, S/S0, was plotted against dose to give the curve shown in Fig. 1.


Author(s):  
D.T. Fefar ◽  
Ankita N. Brahmbhatt ◽  
B.P. Joshi ◽  
D.J. Ghodasara

A study was conducted on 5 weeks old 64 (32 male and 32 female) Swiss albino mice to assess the haemato-biochemical and immunological effects of acetamiprid. All the male and female mice were randomly divided into eight different groups. The groups I (male) and II (female) served as controls whereas remaining groups served as treatment groups and were administered acetamiprid at the daily dose rate of 20, 10, 5 mg/kg body weight in males(Group III, V, VII) and females (Group IV, VI,VIII),respectively for 28 days. After 28 days treatment, blood samples were collected for hematological, biochemical as well as immunological analysis. There was significant decrease in haematological parameters like Hb, TEC, TLC, neutrophils and lymphocytes count in high dose groups and revealed potential adversity of acetamiprid at rates of 20 mg/kg/day on haematopoetic system of mice. A dose dependent significant rise in mean values of AST and ALT was observed in treatment groups, whereas there was significant decrease in total protein and albumin and increase in BUN in high and mid dose treated groups, irrespective of sex of mice. Dinitroflurobenzene (DNFB) test conducted to assess the cell mediated immunity revealed the toxic effect of acetamiprid on cell mediated immunity of mice at dose level of 10 mg/kg/day. The mice of high dose group revealed a significant decrease in HA titer and indicated the immunotoxic potential of acetamiprid at dose level of 20 mg/kg/day.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A303-A303
Author(s):  
George Blumenschein ◽  
Siddhartha Devarakonda ◽  
Melissa Johnson ◽  
Victor Moreno ◽  
Justin Gainor ◽  
...  

BackgroundADP-A2M10 SPEAR T-cells are genetically engineered autologous T-cells that express a high affinity MAGE-A10-specific T-cell receptor targeting MAGE-A10+tumors in the context of HLA-A*02. This trial is now complete (NCT02592577).MethodsThis first-in-human dose escalation trial utilized a modified 3+3 design to evaluate safety and antitumor activity. Eligible patients (pts) were HLA-A*02+ with advanced non-small cell lung cancer (NSCLC) expressing MAGE-A10. Pts underwent apheresis; T-cells were isolated, transduced with a lentiviral vector containing the TCR targeting MAGE-A10, and expanded. Pts underwent lymphodepletion (LD) with varying doses/schedules of fludarabine (Flu) and cyclophosphamide (Cy) prior to receiving ADP-A2M10. ADP-A2M10 was administered at Dose Level (DL) 1= 0.1×109, DL2 0.5–1.2×109, and DL3/Expansion= 1.2–15×109 transduced cells.ResultsAs of Jan 10, 2020, 11 pts (6 male/5 female) with NSCLC (3 squamous cell, 7 adenocarcinoma, 1 adenosquamous) were treated. Five, 3 and 3 pts received cells at DL1, DL2, and DL3/Expansion, respectively. The most frequently reported adverse events ≥ Grade 3 were lymphopenia (11), leukopenia (9), neutropenia (8), anemia (6), thrombocytopenia (5), and hyponatremia (5). Three pts reported CRS (Grades 1, 2, and 4, respectively). One pt received the highest dose of LD (Flu 30 mg/m2 Day 1 4 and Cy 1800 mg/m2 Day 1–2) prior to a second infusion and had a partial response (PR). This pt subsequently developed aplastic anemia and died. Responses included: 1 pt – PR, 3 pts - stable disease, 2 pts – progressive disease, 1 pt - too early to determine, 4 pts - off-study prior to tumor assessment. SPEAR T-cells were detectable in peripheral blood from pts at each dose level, and in tumor tissue from pts at DL1 and DL3.ConclusionsADP-A2M10 SPEAR T-cells have shown acceptable safety and no evidence of toxicity related to off-target binding or alloreactivity. Given the minimal antitumor activity and the discovery that MAGE-A10 expression frequently overlaps with MAGE-A4 expression, the clinical program has closed. Several trials with SPEAR T-cells targeting MAGE-A4 are ongoing (https://bit.ly/35htsZK).Trial RegistrationNCT02592577Ethics ApprovalThe trial was conducted in accordance with the principles of the Declaration of Helsinki and the International Conference on Harmonization Good Clinical Practice guidelines and was approved by local authorities. An independent ethics committee or institutional review board approved the clinical protocol at each participating center. All the patients provided written informed consent before study entry.


2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii306-iii307
Author(s):  
Natasha Pillay Smiley ◽  
Patricia Baxter ◽  
Shiva Kumar ◽  
Eugene Hwang ◽  
John Breneman ◽  
...  

Abstract BACKGROUND BMI-1 is highly expressed in DIPG. Downregulation leads to inhibition of cell proliferation, cell cycle signaling, self-renewal, telomerase expression, activity, and suppression of DIPG cell migration. Targeted inhibition of BMI-1 sensitizes DIPG cells to radiation and drug-induced DNA damage. PTC596 (formulated by PTC Therapeutics, Inc.) is a novel, orally available drug that inhibits microtubule polymerization, resulting in G2/M cell cycle arrest and post-translational modification of BMI-1 protein and reduced BMI-1 protein levels. OBJECTIVES: To estimate the maximum tolerated dose and describe dose limiting toxicities, pharmacokinetics and pharmacodynamics of PTC596 in children 3–21 years of age with newly diagnosed diffuse intrinsic pontine glioma and high-grade gliomas. METHODS PTC596 is administered twice per week orally during radiotherapy and as maintenance for up to two years. The starting dose of PTC596 was 200 mg/m2, with a subsequent dose level of 260mg/m2/dose. Pharmacokinetics are performed in Cycles 1 and 2. RESULTS This study is currently ongoing. Nine patients (7 with DIPG, 2 with HGG), 8 evaluable, have been enrolled. At dose level 1, 200 mg/m2, three evaluable patients were enrolled and experienced no DLTs. At dose level 2, among 5 evaluable patients, 2 experienced dose-limiting grade 4 neutropenia. PTC596 has been otherwise well tolerated. Five patients remain in Cycles 2–11. CONCLUSION This phase I trial is ongoing. PTC596 is tolerable at dose level 1. We are amending the protocol to introduce tablets that can be dissolved in liquid to allow enrollment of younger patients and those unable to swallow whole tablets.


Author(s):  
Dean Wilkinson ◽  
Kelly Mackie ◽  
Dean Novy ◽  
Frances Beaven ◽  
Joanne McNamara ◽  
...  

Abstract Introduction: The Pinnacle3 Auto-Planning (AP) package is an automated inverse planning tool employing a multi-sequence optimisation algorithm. The nature of the optimisation aims to improve the overall quality of radiotherapy plans but at the same time may produce higher modulation, increasing plan complexity and challenging linear accelerator delivery capability. Methods and materials: Thirty patients previously treated with intensity-modulated radiotherapy (IMRT) to the prostate with or without pelvic lymph node irradiation were replanned with locally developed AP techniques for step-and-shoot IMRT (AP-IMRT) and volumetric-modulated arc therapy (AP-VMAT). Each case was also planned with VMAT using conventional inverse planning. The patient cohort was separated into two groups, those with a single primary target volume (PTV) and those with dual PTVs of differing prescription dose levels. Plan complexity was assessed using the modulation complexity score. Results: Plans produced with AP provided equivalent or better dose coverage to target volumes whilst effectively reducing organ at risk (OAR) doses. For IMRT plans, the use of AP resulted in a mean reduction in bladder V50Gy by 4·2 and 4·7 % (p ≤ 0·01) and V40Gy by 4·8 and 11·3 % (p < 0·01) in the single and dual dose level cohorts, respectively. For the rectum, V70Gy, V60Gy and V40Gy were all reduced in the dual dose level AP-VMAT plans by an average of 2·0, 2·7 and 7·3 % (p < 0·01), respectively. A small increase in plan complexity was observed only in dual dose level AP plans. Findings: The automated nature of AP led to high quality treatment plans with improvement in OAR sparing and minimised the variation in achievable dose planning metrics when compared to the conventional inverse planning approach.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A297-A297
Author(s):  
Fu-Sheng Wang ◽  
Fanping Meng ◽  
Jiehua Jin ◽  
Yuanyuan Li ◽  
Regina Wanju Wong ◽  
...  

BackgroundWe have demonstrated the ability of Hepatitis-B-virus (HBV)-specific T cell receptor (TCR) bioengineered T cells to recognize and lyse Hepatocellular carcinoma (HCC) cells expressing HBV antigens derived from HBV-DNA integration in patients with liver transplant.1 LioCyx-M is an immunotherapeutic product composing of autologous T cells transiently modified with in-vitro transcribed mRNA encoding HBV-specific TCR. The transient TCR expression makes LioCyx -M amenable to a dose escalating posology.MethodsThe primary endpoint of this phase 1 trial is to assess the safety and tolerability of LioCyx-M in patients with advanced HBV-HCC without curative treatment options. Eligible patients were diagnosed with Barcelona clinic liver cancer stage B or C HCC (Child-Pugh < 7 points), receiving >1 year antiviral treatment prior to enrollment. These patients had matching HLA class I genotypes which present HBV encoded antigen. Peripheral blood was collected from each patient prior to each dose for LioCyx-M manufacturing. Patients received 4 escalating doses of 1×104 cells/kg, 1×105 cells/kg, 1×106 cells/kg, 5×106 cells/kg bodyweight (BW) in the first treatment cycle, each intravenously administered weekly. Patients underwent 1-month safety assessment post the 4th infusion, according to Common Terminology NCI CTCAE Version 4.0.3. If there were no dose associated toxicities, patients were eligible to continue administration of LioCyx-M at dose of 5 × 106 cells/kg BW weekly. Tumor response per RECIST 1.1 criteria and survival time were assessed.ResultsAt data cutoff (30 April 2020), eight patients were enrolled, with a median age of 53 (range: 49 - 67). These patients received a median number of 6 (range: 4 - 12) infusions of LioCyx-M. 1 patient developed Grade 3 elevations in alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST) and bilirubin after receiving LioCyx-M at dose level of 1×105 cells/kg BW. Another patient had Grade 1 transient fever after receiving LioCyx-M at dose level 5×106 cells/kg BW in the 4th, 5th and 6th infusions. No treatment-related adverse events (trAEs) such as cytokine release syndrome or neurotoxicity were observed. No fatal trAEs were observed. The median time to progression was 1.9 months (range: 0.2 - 9.5 months). The median overall survival was 34 months (range: 3 - 38.2 months).ConclusionsThe encouraging clinical outcome and tolerable safety highlight the good benefit-risk profile of LioCyx-M. Therefore, further exploration of efficacy of LioCyx-M treatment for advanced HBV-HCC is warranted in a Phase 2 proof-of-concept clinical study.AcknowledgementsFunding: Lion TCR.Trial RegistrationNCT03899415Ethics ApprovalThe study was approved by Fifth Medical Center of Chinese PLA General Hospital’s Ethics Board, approval number R2016185DI010.ReferenceTan AT, Yang N, Lee Krishnamoorthy T, et al. Use of Expression Profiles of HBV-DNA Integrated Into Genomes of Hepatocellular Carcinoma Cells to Select T Cells for Immunotherapy. Gastroenterology 2019;156(6):1862–1876.e9.


2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii304-iii304
Author(s):  
Holly Lindsay ◽  
Arzu Onar-Thomas ◽  
Mehmet Kocak ◽  
Tina Young Poussaint ◽  
Girish Dhall ◽  
...  

Abstract BACKGROUND CD40 is a co-stimulatory molecule expressed on antigen presenting cells (APCs). APX005M is a CD40 agonist monoclonal antibody which stimulates innate and adaptive anti-tumor immunity through activation of APCs, macrophages, and antigen-specific CD8+T-cells. Pediatric Brain Tumor Consortium study PBTC-051 is the first investigation of APX005M in pediatric patients and is evaluating the safety, recommended phase 2 dose (RP2D), pharmacokinetics, and preliminary efficacy of APX005M in children with central nervous system (CNS) tumors. RESULTS Accrual of patients with recurrent/refractory primary malignant CNS tumors (stratum 1) began in March 2018. 16 patients (2 ineligible) have enrolled on this stratum; 14 were treated. Dose escalation through 3 planned dose levels of APX005M was completed without excessive or unanticipated toxicities. The highest dose level (0.6 mg/kg q3 weeks) is the presumptive RP2D, and an expansion cohort is currently enrolling at this dose. 2 patients at dose level 3 have received &gt;12 cycles of therapy. Grade 3 or higher adverse events at least possibly attributable to APX005M include 11 lymphopenia, 5 neutropenia, 5 leukopenia, 3 ALT elevations, 1 AST elevation, 1 thrombocytopenia, and 1 hypoalbuminemia. PK data will be available March 2020. Stratum 2 is now enrolling patients with post-radiation/pre-progression DIPG beginning at dose level 2, with 1 patient currently enrolled. CONCLUSION The CD40 agonistic antibody APX005M has demonstrated preliminary safety in pediatric patients with recurrent/refractory primary malignant CNS tumors and has a likely RP2D of 0.6 mg/kg q3 weeks in this population. Preliminary efficacy data are pending.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A322-A322
Author(s):  
Nehal Lakhani ◽  
Marlana Orloff ◽  
Siqing Fu ◽  
Ying Liu ◽  
Yan Wang ◽  
...  

BackgroundIBI188 is a humanized IgG4 monoclonal antibody targeting CD47, an antiphagocytic (‘don’t eat me’) signal present on cancer cells. Blockage of this myeloid checkpoint, IBI188 enhances tumor cell phagocytosis and cross priming of T-cells. We conducted a first-in-human phase 1a trial to evaluate the tolerability, safety and PK/PD characteristics of IBI188. (NCT03763149).MethodsPatients with advanced/refractory solid tumors or lymphoma were enrolled in this two-part dose-escalation study: Part A for testing optimal priming doses at 0.1, 0.3, and 1 mg/kg and Part B for optimal maintenance doses at 3, 10, 20, 30 mg/kg weekly. An accelerated titration followed by traditional 3+3 design was used in this study with a 28-day dose-limiting toxicity (DLT) observation period. Primary endpoint was safety profile; secondary endpoints included PK parameters and PD markers, i.e. CD47 receptor occupancy.ResultsAs of June 18, 2020, 20 patients have been enrolled, 6 in Part A and 14 in Part B. There was no DLT reported at any dose level. The median treatment duration was 1.8 months (0.2–5.5) months. The most common treatment-related adverse events (TRAEs) were nausea (n=7), back pain (n=7), fatigue (n=6), vomiting (n=4) and blood bilirubin increased (n=4). Three patients had ≥ Grade 3 TRAEs (Grade 3 blood bilirubin increase, Grade 4 platelet count decrease and Grade 3 anemia, each in 1 patient). Three of 20 patients (15%) had anemia, an expected TRAE associated with the mechanism of IBI188. Majority of the patients (65%) had infusion related reactions (IRR). All IRRs were Grade 1–2 and able to be managed with standard IRR treatment. The clearance of IBI188 decreased with the increasing dose from 3 to 20 mg/kg and IBI188 can overcome the sink at 10 mg/kg or higher dose level. The PK analysis at 30 mg/kg is ongoing. The 10 mg/kg maintenance dose resulted in T cells receptor occupancy above 80%. After multiple administrations (≥ 3 times, including the priming dose), the RBC and T cells receptor occupancy tends to be stable and maintained around 90%. The receptor occupancy analysis at 20 mg/kg and 30 mg/kg is ongoing.ConclusionsIBI188 was well tolerated at 1 mg/kg priming dose following by the maintenance dose up to 30 mg/kg.Trial RegistrationNCT03763149


Parasitology ◽  
1973 ◽  
Vol 66 (2) ◽  
pp. 355-365 ◽  
Author(s):  
C. A. Hopkins ◽  
P. M. Grant ◽  
Helen Stallard

The effect of oxyclozanide (2,2′-dihydroxy-3,3′,5,5′,6-pentachlorobenzanilide) on Hymenolepis microstoma in the bile duct of mice, and H. diminuta in the small intestine of mice and rats was measured. Oxyclozanide at doses as low as 4mg/kg removed 13-day-old H. diminuta and caused no obvious harmful effect to the rat host up to the maximum level (256 mg/kg) tested. Worms were displaced and degenerating within 1 h. Results in mice were more difficult to assess because of the immune response, but similar total amounts of oxyclozanide caused destrobilation and loss of 7-day-old H. diminuta. Oxyclozanide was less effective against 21-day-old H. microstoma attached in the bile duct. Approximately half the strobila was lost following dosing at 5 mg/kg and progressively greater amounts as the dose level was increased. At 50 mg/kg worm loss commenced but even at 150 mg/kg 25 % of worms survived. The time taken to regrow to the original adult size varied but was complete within 7–9 days at levels up to 25 mg/kg. Double dosing at 5-day intervals did not enhance the effect of a single dose. The apparent existence of a sensitivity gradient down the strobila in H. microstoma is discussed.


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