The minimum effective dose (ED90) of prophylactic oxytocin infusion during cesarean delivery in patients with and without obesity: an up-down sequential allocation dose-response study

BACKGROUND

Obesity is associated with greater oxytocin requirement during labor induction or augmentation. There are scant data exploring the intra-operative requirement during cesarean delivery in patients with obesity, and none comparing it with those without obesity. We evaluated the minimum effective dose (ED90) of an oxytocin infusion to achieve adequate uterine tone during cesarean delivery in patients with and without obesity.

METHODS

Patients (body mass index ≥30 kg/m2 represented patients with obesity) undergoing cesarean delivery using subarachnoid block were included. This prospective dual-arm dose-finding study used a 9:1 biased sequential allocation design. Oxytocin infusion was initiated at 13 IU/h at cord clamping in the first patient of each group. Uterine tone was graded as satisfactory or unsatisfactory by the obstetrician four minutes after initiation of the infusion. The dose of oxytocin infusion for subsequent patients was determined according to the response of the previous patient in the group. Oxytocin-associated side effects were evaluated. Dose-response data for the groups was evaluated using log-logistic function and ED90 estimates derived from fitted equations using the delta method.

RESULTS

The ED90 of oxytocin was significantly higher for patients with obesity (n = 40) compared with those without obesity (n = 40) [25.7 IU/h, 95% CI 18.6 to 32.9) vs. 16.6 IU/h, 95% CI 14.9 to 18.3)]; relative ratio 1.55 [95% CI 1.09 to 2.01] (P = 0.019).

CONCLUSIONS

Patients with obesity require a higher intra-operative oxytocin infusion dose rate to achieve a satisfactorily contracted uterus after fetal delivery when compared with patients without obesity.

TP-0184 inhibits FLT3/ACVR1 to overcome FLT3 inhibitor resistance and hinder AML growth synergistically with venetoclax

We identified activin A receptor type I (ACVR1), a member of the TGF-β superfamily, as a factor favoring acute myeloid leukemia (AML) growth and a new potential therapeutic target. ACVR1 is overexpressed in FLT3-mutated AML and inhibition of ACVR1 expression sensitized AML cells to FLT3 inhibitors. We developed a novel ACVR1 inhibitor, TP-0184, which selectively caused growth arrest in FLT3-mutated AML cell lines. Molecular docking and in vitro kinase assays revealed that TP-0184 binds to both ACVR1 and FLT3 with high affinity and inhibits FLT3/ACVR1 downstream signaling. Treatment with TP-0184 or in combination with BCL2 inhibitor, venetoclax dramatically inhibited leukemia growth in FLT3-mutated AML cell lines and patient-derived xenograft models in a dose-dependent manner. These findings suggest that ACVR1 is a novel biomarker and plays a role in AML resistance to FLT3 inhibitors and that FLT3/ACVR1 dual inhibitor TP-0184 is a novel potential therapeutic tool for AML with FLT3 mutations.

Calculation of effective dose of phenylephrine bolus for treatment of post-spinal hypotension in pre-eclamptic patients undergoing caesarean section - a non-randomised controlled trial

BACKGROUND

Patients with pre-eclampsia require smaller vasopressor doses compared with those with normotension for management of post-spinal hypotension during caesarean section. However, the literature has little evidence as to the phenylephrine dose required for patients with pre-eclampsia.

METHODS

Fifty patients, with either pre-eclampsia or normotension, and developing post-spinal hypotension during caesarean section under spinal anaesthesia, were studied. Women in both groups did not receive prophylactic vasopressors. The first patient in each group received phenylephrine 50 µg to treat the first episode of hypotension, defined as fall of systolic blood pressure ≥20% from baseline or an absolute value <100 mmHg. If hypotension was corrected within one minute it was considered a 'success'. The doses for the subsequent patients were determined by responses to all previous patients, according to a variation of Narayana's rule for the up-down sequential allocation method.

RESULTS

The 95% effective dose (ED95) and 50% effective dose (ED50) of phenylephrine was 41.7 µg (95% CI 33.8 to 49.6 µg) and 29.1 µg (95% CI 26.0 to 32.2 µg) respectively in the pre-eclampsia group, and 64.9 µg (95% CI 54.1 to 75.7 µg) and 47.3 µg (95% CI 39.7 to 54.9 µg) respectively in the normotensive group. The proportionate reduction in phenylephrine dose ranged from 33% (95% CI 18 to 44%) to 40% (95% CI 19 to 52%).

CONCLUSION

Patients with pre-eclampsia may need a 33% to 40% reduction in the first phenylephrine bolus dose, compared with patients with normotension, for the treatment of the first episode of post-spinal hypotension.

Abstract 5098: B7-H3 blockade in combination with natural killer cell activity enhancers including NKTR-255 and venetoclax synergistically induces cytotoxicity in B7-H3+ AML cells

Background: Acute myeloid leukemia (AML) is characterized by clonal proliferation of malignant myeloid blasts in the bone marrow. We have recently reported that blocking B7-H3 using a novel monoclonal antibody (mAB), T-1A5 enhances natural killer (NK) cell mediated cytotoxicity against AML cells. IL-15 is an essential component for NK cell activity. Recombinant human IL-15 (rIL-15), however, degrades rapidly and therefore may provide a suboptimal stimulus to NK cells. Studies have shown that BCL2 inhibitor, venetoclax (ABT-199), enhances NK cell induced antibody dependent cellular cytotoxicity (ADCC) against cancer cells. However, the combined effect of B7-H3 blocking and BCL2 inhibition remains unexplored in AML. We hypothesized that blocking B7-H3 using T-1A5 in the presence of novel investigational polymer-engineered IL-15 receptor agonist, NKTR-255, and the BCL2 inhibitor synergistically induces NK cell mediated ADCC in AML cells.

Methods: CD16 and NKG2D activation markers measured by flow cytometry in AML patient and healthy donor derived NK cells. The NKTR-255 was used to generate NK cells, and their cytotoxicity was compared to that of NK cells generated with rIL-15 using IncuCyte. To investigate these NK cells’ cytotoxic activity against AML cells, we treated B7-H3+ AML cell lines (OCI-AML3 and MV4-11) with anti-B7-H3 chimeric mAb ChT-1A5 in the presence and absence of NK cells generated using NKTR-255 or rIL-15. To assess the potential synergy of BCL2 and B7-H3 in NK cell mediated anti-leukemic activity against AML cells, we treated B7-H3+ cells with T-1A5 with or without ABT-199in the presence or absence of NK cells.

Results: The expression of NK cell activation markers were significantly lower in NK cells derived from AML patients than healthy donors. To assess the effect of NKTR-255 on NK cell activity, we generated NK cells using NKTR-255 and compared them with NK cells generated using rIL-15 using the standard 14-day culture protocol. We observed similar proliferation and NK cell numbers between NKTR-255 and rIL-15. However, NK cells stimulated with NKTR-255 showed significantly enhanced (more than 2-fold) cytolytic activity against B7-H3+ AML cell lines compared with NK cells stimulated with rIL-15. Moreover, when combined with ChT-1A5, NKTR-255 significantly enhanced NK cell mediated ADCC activity in B7-H3+ AML cells compared to rIL-15. Interestingly, we observed that the combination of T-1A5 and venetoclax synergistically induced an anti-leukemic effect in B7-H3+ AML cell lines when compared with either drug alone or isotype IgG1 in a dose-dependent manner.

Conclusion: Our data demonstrate that blockade of the immune checkpoint protein, B7-H3 with the IL-15 receptor agonist, NKTR-255, or the BCL2 inhibitor, ABT-199, synergistically induces NK cell mediated cytotoxicity against B7-H3+ AML cells.

Citation Format: Anudishi Tyagi, A. Mario Marcondes, Willem Overwijk, Venkata Lokesh Battula. B7-H3 blockade in combination with natural killer cell activity enhancers including NKTR-255 and venetoclax synergistically induces cytotoxicity in B7-H3+ AML cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5098.

Abstract 5115: Novel humanized anti-GD2 antibody inhibits GD2-mediated immunosuppression by targeting GD2+ breast cancer stem-like cells

Background: Breast cancer stem-like cells (BCSCs) are reported to be a major contributing factor for tumor growth and chemotherapy resistance in triple-negative breast cancer (TNBC). We reported that the disialoganglioside GD2 is highly expressed on BCSCs and that targeting GD2 with dinutuximab (chimeric anti-GD2 antibody) in combination with NK cells synergistically reduced tumor volumes in TNBC animal models. Here, we hypothesize that naxitamab targets GD2+ BCSCs and inhibits breast cancer (BC) growth by enhancing macrophage mediated phagocytosis and T cell mediated cytotoxicity. In addition, we explore whether addition of an investigational polymer-engineered IL-15 receptor-agonist, NKTR-255 treated NK cells, can further enhance this anti-GD2 mediated anti-cancer activity.

Methods: Naxitamab is a US FDA approved fully humanized anti-GD2 (hu3F8) monoclonal antibody for the treatment of pediatric neuroblastoma. We evaluated the effects of naxitamab treatment on macrophage mediated phagocytosis of BC cells using the live cell imaging system, IncuCyte®. Next, we compared the effects of NKTR-255 treated NK cells with recombinant human IL-15 (rIL-15) treated NK cells in naxitamab induced ADCC in GD2+ BC cells. We also performed immunohistochemistry (IHC) to examine GD2 expression and correlate it with T cell infiltration in primary TNBC patient samples with high and low GD2 levels. The effect of naxitamab treatment on T cell mediated cytotoxicity in BC cells was also observed.

Results: When compared to control, naxitamab treatment promoted macrophage mediated phagocytosis of Hs578T and HCC1395 cells in a dose dependent manner (p &lt;0.001). Additionally, when co-cultured with healthy donor derived macrophages, we found a significant reduction in Hs578T spheroids treated with naxitamab in comparison to IgG control (p&lt;0.001). Furthermore, we observed a significantly higher rate of apoptosis in GD2+ Hs578T and HCC1395 breast cancer cells treated with naxitamab and NK cells generated using NKTR-255, compared to rIL-15 treated NK cells (p&lt;0.0001). Interestingly, IHC analysis showed that TNBC patients with high GD2 expression have significantly lower CD3+ T cell infiltration than patients with low GD2 expression (p&lt;0.05). We also observed increased T cell mediated killing of BT549 and T47D cells treated with naxitamab in comparison to IgG control (p&lt;0.001).

Conclusion: TNBC with high GD2 expression inhibits immune cell infiltration and naxitamab can inhibit BCSC growth by targeting GD2. Combination of naxitamab with macrophages induced macrophage mediated phagocytosis TNBC cells. NK cells were more stable and cytotoxic when generated with NKTR-255 vs. native IL-15, and naxitamab further enhanced NK cell mediated ADCC of GD2+ BCSCs. The increased T cell mediated killing of breast cancer cells treated with naxitamab further supports the immunomodulatory role of GD2.

Citation Format: Vivek Anand, Venkatesh Hegde, Maryam Siddiqui, Anudishi Tyagi, Bolutyfe Oderinde, Mario Marcondes, Willem Overwijk, Venkata Lokesh Battula. Novel humanized anti-GD2 antibody inhibits GD2-mediated immunosuppression by targeting GD2+ breast cancer stem-like cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5115.

Abstract P2-20-06: Anti-B7-H3 Antibody (T-1A5) Blocks Immunomodulatory Function of B7-H3 and Enhances NK and T Cell–Mediated Cytotoxicity against Breast Cancer Cells

One of the main factors contributing to breast cancer (BC) initiation and metastasis is immune suppression by tumor cells. Immune checkpoint blockade has recently been shown to overcome tumor-induced immune suppression, but a significant proportion of patients do not respond, implying that more effective cancer immunotherapies are required. B7-H3 belongs to B7 family of immune checkpoint proteins that is overexpressed in various human malignancies. Here, we hypothesize that blocking B7-H3 using monoclonal antibodies (mAbs) enhances immune cell proliferation and function. To test our hypothesis, B7-H3 expression was determined using RNA-seq data from primary and metastatic breast tumors, and adjacent normal tissues, from the TCGA and METABRIC databases. To assess B7-H3 protein expression in BC, we performed immunohistochemistry (IHC) on frozen primary tumor tissues (n=50) and adjacent normal tissues (n=23) from TNBC patients. In addition, to investigate the immunomodulatory effect of B7-H3 in BC, we performed IHC for T-cell markers in subsets of patient tissues with high and low levels of B7-H3 expression. Next, we assessed B7-H3 expression in over 13 BC cell lines, including TNBC and ER+, PR+, and HER2+ cell lines, as well as TNBC PDX-derived cells. Moreover, to determine the effect of B7-H3 knockdown on NK- and T-cell activity, we co-cultured control and B7H3–KD BC cells in the presence and absence of NK and T cells and measured the induction of apoptosis in BC cells through IncuCyte live-cell imaging system. The effect of a novel B7H3-blocking mAb (clone T-1A5, isotype IgG1) on NK-cell and T-cell-mediated cytotoxicity in BC cell lines was examined using live-cell imaging. In the TCGA and METABRIC databases, B7-H3 was found to be significantly overexpressed (P&lt; 0.0001) in tumor tissues than in adjacent normal tissues of BC patients. A survival analysis by the log-rank test indicated that patients with B7-H3high tumors had significantly lower progression-free (P=0.01) and relapse-free (P=0.0026) survival than patients with B7-H3low tumors. Moreover, B7-H3 is significantly upregulated in all the BC subtypes including basal, luminal A, luminal B and Her2-enriched with highest expression in basal type BC. Relative mRNA quantification and flow cytometry analysis demonstrated strong B7-H3 expression in most of the BC cell lines including TNBC and ER+, PR+, and HER2+ cell lines, as well as TNBC PDX-derived cells. Furthermore, IHC analysis revealed that compared to the matched normal tissue, B7-H3 expression was substantially higher in tumor tissue (N=16, P&lt; 0.001). Also, patients with high B7-H3 expression had significantly lower numbers of CD3+, CD4+, and CD8+ T-cell, compared to patients with low B7-H3 expression (P&lt; 0.001), indicating immunosuppressive role of B7-H3. Furthermore, NK cell and T cell mediated killing was significantly higher in B7H3-KD BC cell lines compared to control cells. We observed a significant increase in the killing of BC cells by NK cells and T cells in the presence of anti-B7H3 mAb T-1A5 in a concentration dependent manner (P &lt; 0.001), suggesting that anti-B7H3 antibodies suppress the immunomodulatory function of B7-H3 and enhance NK and T cell–mediated ADCC in BC. To determine the antibody-dependent cell-mediated cytotoxicity, we developed a human-mouse chimera of T-1A5 (chT-1A5) and tested in combination with NK cells. Interestingly, we found a concentration and time dependent increase in ADCC in BC cells in the presence of chT-1A5 antibody. Our data suggests that B7-H3 is overexpressed in primary BC and inhibits immune-cell infiltration. Moreover, blocking the immunomodulatory functions of B7-H3 using anti-B7H3 antibody T-1A5 enhances NK and T cell–mediated killing of BC cells.

Citation Format: Vivek Anand, Anudishi Tyagi, Venkata Lokesh Battula. Anti-B7-H3 Antibody (T-1A5) Blocks Immunomodulatory Function of B7-H3 and Enhances NK and T Cell–Mediated Cytotoxicity against Breast Cancer Cells [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-20-06.

Crosstalk between H2 S and NO: an emerging signalling pathway during waterlogging stress in legume crops

In legumes, waterlogging is a major detrimental factor leading to huge yield losses. Generally, legumes lack tolerance to submergence, and conventional breeding to develop tolerant varieties are limited due to the lack of tolerant germplasm and potential target genes. Moreover, our understanding of the various signalling cascades, their interactions and key pathways induced during waterlogging is limited. Here, we focus on the role of two important plant signalling molecules, viz. hydrogen sulphide (H₂ S) and nitric oxide (NO), during waterlogging stress in legumes. Plants and soil microbes produce these signalling molecules both endogenously and exogenously under various stresses, including waterlogging. NO and H₂ S are known to regulate key physiological pathways, such as stomatal closure, leaf senescence and regulation of numerous stress signalling pathways, while NO plays a pivotal role in adventitious root formation during waterlogging. The crosstalk between H₂ S and NO is synergistic because of the resemblance of their physiological effects and proteomic functions, which mainly operate through cysteine-dependent post-translational modifications via S-nitrosation and persulfidation. Such knowledge has provided novel platforms for researchers to unravel the complexity associated with H₂ S-NO signalling and interactions with plant stress hormones. This review provides an overall summary on H₂ S and NO, including biosynthesis, biological importance, crosstalk, transporter regulation as well as understanding their role during waterlogging using 'multi-omics' approach. Understanding H₂ S and NO signalling will help in deciphering the metabolic interactions and identifying key regulatory genes that could be used for developing waterlogging tolerance in legumes.

Evidence supporting a role for the immune checkpoint protein B7-H3 in NK cell-mediated cytotoxicity against AML

We observed that the immune checkpoint protein B7-H3 is overexpressed in acute myeloid leukemia (AML) patients with poor treatment outcomes. Inhibition of B7-H3 expression or blocking of its activity using a novel monoclonal antibody (T-1A5) in AML cells significantly enhanced natural killer (NK) cell-mediated cytotoxicity in AML cells in vitro and in vivo. Moreover, a human-mouse chimera of this antibody (ChT-1A5) induced antibody-dependent cell-mediated cytotoxicity (ADCC) in B7-H3+ primary AML cells, but not in normal hematopoietic cells, suggesting the specify of this antibody for AML cells. Epitope mapping studies identified that both T-1A5 and ChT-1A5 antibodies bind to the FG-loop region of B7-H3, which is known to regulate the immunosuppressive function of B7-H3. Furthermore, treatment with ChT-1A5 in combination with human NK cells significantly prolonged survival in AML patient-derived xenograft (PDX) models. Our results suggest that the ChT-1A5 antibody can inhibit the immunosuppressive function of B7-H3 protein as well as induce ADCC in B7-H3+ AML.

Clinical correlation and assessment of olfactory dysfunction with n-butanol in COVID-19 patients: our experience

Background: Studies showed olfactory disturbances in COVID patients. This has attracted focus of clinicians as an easy clinical screening tool in suspected population. Material and methods: 70 mild and moderate category COVID-19 RT-PCR positive patients, more than 10 years of age were tested on day of admission for olfaction with serial dilution of n-butanol and asked to grade severity of their olfactory dysfunction according to visual analogue score from 1-10. Results: Fatigue 42 (93.33%), sore throat 37 (82.22%), fever 36 (80%) and dyspnea 23 (51.11%) were the most common symptoms in moderate patients. Diabetes, hypertension and allergy were the three prominent risk factors. At time of admission, n-butanol diagnosed 20 patients having olfactory dysfunction compared to 11 by VAS. Patients tend to grade their dysfunction higher on VAS whereas the n-butanol test classified their olfactory dysfunction lower. Viral load and high CRP were not found to be significantly related with olfactory dysfunction. d-Dimer and LDH levels were found statistically associated with higher grading of olfactory dysfunction detected by n-butanol. Conclusion: The majority of cases developed hyposmia before they were admitted to hospital even before they realized that they were having hyposmia as revealed by n-butanol testing. We should go for objective tests of olfaction.

Utility of serum Galactomannan in diagnosing COVID-19 patients with suspected IPA: an observational study in resource limited settings

OBJECTIVE

To study the utility of Galactomannan (GM) antigen as a screening marker for diagnosing invasive pulmonary aspergillosis (IPA) in coronavirus disease 2019 (COVID-19) patients.

PATIENTS AND METHODS

The serum samples from patients with severe COVID-19 diseases admitted to the Critical Care Unit were collected on the 5th day of admission for GM screening. The samples were analysed by enzyme linked immune sorbent assay (ELISA) and GM index of more than 1 was considered as positive. All GM positive patients were serially followed until discharge or death.

RESULTS

The GM was raised in serum of 12 out of 38 patients, indicating an incidence of possible COVID-19 associated IPA (CAPA) in 31.57% of patients. The median age of these CAPA patients was 56.5 years, males were significantly more affected than females. The inflammatory marker serum ferritin was raised in all 12 patients (median value of 713.74 ng/ml), while IL-6 was raised in 9 patients (median value of 54.13 ng/ml). None of these patients received antifungals. Their median length of hospital stay was 20 days (IQR: 12, 34 days). All these patients succumbed to the illness.

CONCLUSIONS

The serum GM appears to be sensitive diagnostic tool to identify early IPA in COVID-19 patients and pre-emptive antifungal therapy could play a role in salvaging these patients.

Post-operative volumes following endoscopic surgery for non-functioning pituitary macroadenomas are predictive of further intervention, but not endocrine outcomes

BACKGROUND

Transsphenoidal surgery (TSS) remains the treatment of choice for non-functioning pituitary macroadenomas (NFPMA). The value of measuring tumour volumes before and after surgery, and its influence on endocrine outcomes and further treatment of the residual or recurrent tumour are unknown.

METHODS

Data from patients who underwent endoscopic TSS for a NFPMA (2009-2018) in a UK tertiary centre were analysed for pre- and post-operative endocrine and surgical outcomes.

RESULTS

Of 173 patients with NFPMA, 159 (61% male) were treatment naïve. At presentation, 76.2% (77/101) had ≥1 pituitary axis deficit. Older age (p = 0.002) was an independent predictor for multiple hormonal deficiencies. Preoperative tumour volume did not correlate with degree of hypopituitarism. Postoperative tumour volume and extent of tumour resection were not predictive of new onset hypopituitarism. Hormonal recovery was observed in 16 patients (20.8%) with impaired pituitary function, with the greatest recovery in the hypothalamic-pituitary-adrenal axis (21.2%, 7/33). A larger residual tumour volume was predictive of adjuvant radiotherapy (3.40 vs. 1.24 cm³, p = 0.005) and likelihood for repeat surgery (5.40 vs. 1.67cm³, p = 0.004).

CONCLUSION

Pre- and post-operative NFPMA volumes fail to predict the number of pituitary hormone deficits, however, greater post-operative residual volumes increase the likelihood of further intervention to control tumour growth.

Potential association between recurrent facial nerve palsy and migraines

OBJECTIVE

This study aimed to investigate the possible association between recurrent facial nerve palsy and migraines.

METHOD

This study was a prospective case series with a two-year follow-up at an academic, tertiary referral centre and included patients with at least four episodes of recurrent lower motor neuron facial nerve palsy. All patients underwent standardised diagnostic tests.

RESULTS

Four patients fulfilled the inclusion criteria. The patients were all female with an average age at presentation of 40.75 years (range, 33-60 years) and an average age at the initial episode of 14 years (range, 12-16 years). The number of episodes varied between six and nine. All patients had at least one episode of facial nerve palsy on the contralateral side. Two patients were diagnosed and treated for migraine with aura remaining asymptomatic following prophylactic medication for migraines.

CONCLUSION

The results raise the possibility of an association between recurrent facial nerve palsy and migraines. Prospective studies in patients with even fewer episodes of facial nerve palsy could shed more light on this association.

Evaluation of Vascular Endothelial Growth Factor (VEGF) and Thrombospondin-1 as Biomarkers of Metronomic Chemotherapy in Progressive Pediatric Solid Malignancies

OBJECTIVE

We compared Vascular Endothelial Growth factor (VEGF) and Thrombospondin-1 between patients with progressive paediatric malignancies randomized to metronomic chemotherapy versus placebo to determine their role as biomarker.

METHODS

In this double-blinded, placebo-controlled randomized study of 108 progressive pediatric malignancies, serum VEGF and thrombospondin-1 levels were evaluated using ELISA at baseline, A2 (week-9 or earlier if progressed) and A3 (week-18 or earlier if progressed).

RESULTS

Mean VEGF and thrombospondin-1 at baseline, A2 and A3 and the change from baseline to A2 were not different between two groups. In metronomic arm, responders (those completing 3 cycles) had significantly lower mean (SD) baseline VEGF levels [659.7(362.1) vs 1143.9 (622.0) µg/mL] (P=0.002) and significant decrease in thrombospondin-1 from baseline to A2 [-4.43(8.0) µg/mL vs 1.7(11.3) µg/mL] (P=0.04), as compared to non-responders. Similar changes were not observed in responders on placebo arm. No consistent trend of these biomarkers was observed.

CONCLUSIONS

VEGF and thrombospondin-1 are not reliable biomarkers for response to metronomic chemotherapy.

Study of Dosimetric Properties of Flattening Filter Free Photon Beam Passing through Cadmium Free Compensator Alloy

BACKGROUND

This study aims to investigate radiation beam geometry of Cyberknife beam and change in dosimetric characteristics of six megavoltage (6MV) flattening filter free (FFF) beam after passing through high density cadmium free compensator alloy.

MATERIAL AND METHODS

In this experimental study, changes in FFF beam dosimetric characteristics after passing through compensator alloy was measured. Transmitted intensity of FFF beam was measured in air by an ion chamber at a source to detector distance (SDD) of 800mm. Extended SDD measurement also has been performed at a distance of 1270mm to analyze scattering due to compensator. Linear attenuation coefficient (µ_eff) was measured for cadmium free compensator alloy using simple exponential attenuation model. Percentage depth doses (PDDs) have been measured by a radiation field analyzer with compensator material to observe the beam hardening and change in surface doses and depth doses.

RESULTS

Linear attenuation coefficient of compensator alloy was measured 0.042 (Standard Deviation ±0.00099) mm^-1 and it was found that there is no change with increase in collimator size. Even after increasing distance source from detector, µ_eff has no change. PDDs were found to increase with thickness of compensator. PDD from a 60mm collimator size increased by 5% and 6% at a depth of 100mm and 200mm, respectively in water. PDD also increased with collimator size less significantly. Surface dose was found to decrease with increase in compensator thickness.

CONCLUSION

Cyberknife beam has been found to be narrow beam geometry. FFF beam contains lesser scattered photons. Presence of high density compensator filters out the soft x-ray photon causes significant dosimetric changes.

Genetic Landscape of Mitochondrial Regulatory Region in Pediatric Acute Myeloid Leukemia: Changes from Diagnosis to Relapse

This prospective study aimed to compare the pattern of mitochondrial deoxyribonucleic acid D-loop (mt-DNA D-loop) variations in 41 paired samples of de novo pediatric acute myeloid leukemia (AML) (baseline vs. relapse) patients by Sanger's sequencing. Mean mt-DNA D-loop variation was 10.1 at baseline as compared with 9.4 per patients at relapse. In our study, 28 (68.3%) patients showed change in number of variations from baseline to relapse, 11 (26.8%) patients showed increase, 17 (41.6%) patients showed decrease, and 7 (17.1%) patients who suffered a relapse had a gain at position T489C. No statistically significant difference was observed in the mutation profile of mt-DNA D-loop region from baseline to relapse in the evaluated population of pediatric AML.

FP2-1 Prognostic value of leucocytosis in paediatric traumatic brain injury

Objectives

We assessed leucocytosis and evaluated its prognostic value in isolated paediatric traumatic brain injury (TBI).

Design

Retrospective analysis.

Subjects

106 consecutive paediatric patients with isolated TBI admitted between June 2008 and June 2016.

Methods

Initial blood leucocyte count (WCC), Glasgow Coma Score (GCS), computed tomographic (CT) findings, duration of hospital stay, and Paediatric Cerebral Performance Category Scale (PCPCS) scores were analysed.

Results

Mean age was 4.2 years. For patients with GCS 3–8, 9–13 and 14–15, WCC was 20, 15.9 and 10.7 × 109/L respectively. Differences in WCC were significant between the different GCS groups (p<0.01). Length of hospital stay, extent of midline shift on CT and poor 6 month PCPCS rating were each significantly correlated with WCC (p<0.05). Multivariate regression analysis revealed a cut-off WCC of 16.1 × 109/L, above which GCS, CT findings, length of hospital stay and PCPCS were less favourable. Application of the International Mission on Prognosis and Analysis of randomized Controlled Trials in TBI (IMPACT) adult TBI prediction model to our paediatric cohort, using area under the operating curve (AUROC) and coefficient analyses, demonstrated increased accuracy with incorporation of WCC as a risk factor.

Conclusions

High initial leucocytosis (>16.1×109/L) is predictive for poor GCS, severe CT findings, lengthy hospital stay and poor PCPCS in isolated paediatric TBI. Incorporating WCC into TBI prediction models may increase the accuracy of prognostication.

Prognostic impact of mitochondrial DNA D-loop variations in pediatric acute myeloid leukemia

The role of mitochondrial DNA (mt-DNA) changes, especially those in the regulatory D-loop region in Acute Myeloid Leukemia (AML) remains investigational. Consecutive 151 de novo pediatric AML patients, (≤18 yr) were prospectively enrolled from June 2013-August 2016, to assess the prognostic impact of mt-DNA D-loop variations (somatic/germline) on survival. For each patient, D-loop region was sequenced on baseline bone marrow and buccal swab, and mother’s blood sample. In 151 AML subjects, 1490 variations were found at 237 positions; 80.9% were germline and 19.1% somatic. The mean number of variations per position was 6.3. Variations with frequency ≥6 were analyzed for their impact on survival and 4 categories were created, namely “somatic-protective”, “somatic-hazardous”, “germline-protective” and “germline- hazardous”. Although, somatic-protective could not predict event free survival (EFS) or overall survival (OS), somatic-hazardous [(OS) HR = 2.33, p = 0.06] and germline-hazardous [(OS) HR = 2.85, p < 0.01] significantly predicted OS and EFS. Notably, the germline-protective, could significantly predict EFS (HR = 0.31, p = 0.03) and OS (HR = 0.19, p < 0.01), only when variations at ≥2 positions were present. On multivariate analysis, three positions namely 16111, 16126, 16362 and karyotype were found to be predictive of EFS. A prognostic index (PI) was developed using nomogram PI = (0.8*karyotype) + (1.0*c16111) + (0.7*t16362) + (1.2*t16126). Hazard ratio for EFS increased significantly with increasing PI reaching to a maximum of 3.3 (p < 0.01). In conclusion, the impact of mt-DNA D-loop variations on outcomes in pediatric AML depends on their nature (germline/somatic), position and mutational burden, highlighting their potential role as evolving prognostic biomarkers.

Rate-dependent Left Bundle Branch Block during Anaesthesia

Rate-dependent left bundle branch block during general anaesthesia is rare. Its occurrence makes electrocardiographic diagnosis of acute myocardial ischaemia or infarction difficult. It can also be confused with a slow rate ventricular tachycardia. We present a case of rate-dependent left bundle branch block in a patient with no previous history of ischaemic heart disease. Carotid sinus massage resulted in a decrease in heart rate and reversion to normal sinus rhythm.

Apoptosis: A biomarker of high-risk phenotype in pediatric acute myeloid leukemia?

INTRODUCTION

Dysregulation of apoptosis has been explored in acute myeloid leukemia (AML); yet, its correlation with clinical outcomes in pediatric AML is unknown. This study was aimed to analyze percentage of apoptosis and apoptosis mediated through the intrinsic pathway with clinical outcomes in patients with pediatric AML.

METHODS

This prospective study included pediatric AML patients enrolled from July 2013 to August 2016. Annexin-V (marker of total apoptosis) and caspase-9 expression (marker of intrinsic pathway) was determined in baseline bone marrow (BM) samples by flow cytometery and compared with controls (unaffected BM of solid tumors and peripheral blood [PB] of unaffected siblings). Overall survival (OS) and event-free survival (EFS) were compared using log-rank test.

RESULTS

A total of 151 AML patients were enrolled, median age 10 (range: 0.7-18 years). Annexin-V expression in blast cells was significantly high in AML patients as compared to BM of subjects with solid tumors (P = 0.01) and PB of healthy subjects (P = 0.04). Caspase-9 expression in blast cells was not significantly different. Median annexin-V expression was significantly higher in patients with WBC count ≥11 000/mm³ (P = 0.02), poor-risk cytogenetics (P = 0.02), the absence of RUNX1-RUNX1T1 translocation (P = 0.004), and the absence of NPM1 mutation (P = 0.05). Patients with high annexin-V expression had significantly inferior OS (P = 0.05) in univariate analysis but not in multivariate analysis (P = 0.32).

CONCLUSION

Apoptosis as a whole was found to be activated in baseline BM samples of AML patients. High apoptosis may be associated with high-risk phenotype in this disease.

Epidemiology of acute kidney injury and the role of urinary [TIMP-2]·[IGFBP7]: a prospective cohort study in critically ill obstetric patients

BACKGROUND

There are few data regarding acute kidney injury in critically-ill obstetric patients. A combination of urinary cell cycle arrest markers, tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor binding protein7 (IGFBP7), is validated for the early prediction of acute kidney injury in non-obstetric patients.

METHODS

We evaluated the epidemiology of acute kidney injury in critically-ill obstetric patients and the role of the biomarker combination in predicting acute kidney injury and mortality. Acute kidney injury, its severity and risk factors, were assessed using Kidney Disease: Improving Global Outcomes (KDIGO) guidelines during the intensive care unit stay. An ELISA technique measured TIMP-2 and IGFBP7 in urine samples collected at the time of admission there.

RESULTS

Results for 66 patients showed an overall incidence of acute kidney injury of 40/66 (61%), with 50%, 10% and 40% being in stage 1, 2 and 3 respectively. Patients with acute kidney injury showed significantly greater sepsis and shock; longer stay and higher mortality during intensive care (33% vs 0%) and in hospital (38% vs 0%) compared to those without (P <0.05). The area-under-the receiver operating characteristics curve was <0.5 for urinary [TIMP-2]·[IGFBP7] as a predictor of kidney injury and mortality (P >0.05).

CONCLUSIONS

Acute kidney injury is common in critically-ill obstetric patients, increasing mortality and duration of hospitalization. It was significantly more common in patients with septic shock. Previously validated results of urinary [TIMP-2]·[IGFBP7] that successfully predict early acute kidney injury or mortality are not applicable to obstetric patients.

Pattern of mitochondrial D-loop variations and their relation with mitochondrial encoded genes in pediatric acute myeloid leukemia

Role of mitochondrial DNA variations, particularly in D loop region, remains investigational in acute myeloid leukaemia (AML). Consecutive 151 pediatric AML patients were prospectively enrolled from June 2013 to August 2016, for evaluating pattern of variations in mitochondrial D-loop region and to determine their association, if any, with expression of mitochondrial-encoded genes. For each patient, D-loop region was sequenced on baseline bone marrow, buccal swab and mother's blood sample. Real time PCR was used for relative gene expression of four mitochondrial DNA encoded genes viz. Nicotinamide-adenine-dineucleotide-dehydrogenase subunit 3 (ND3), Cytochrome-B (Cyt-B), Cytochrome c oxidase-I (COX1) and ATP-synthetase F₀ subunit-6 (ATP6). Total 1490 variations were found at 237 positions in D-Loop; 1206 (80.9%) were germline and 284 (19.1%) were somatic. Positions 73-263 were identified as a probable hotspot region. G bases appeared to be most stable nucleotide (least number of single base substitutions) whereas T appeared to be most susceptible to variations with germline T-C being the commonest. Gene expression of Cyt-B was found to be significantly higher for any variation (somatic or germline) at positions 16,192 and 16,327 while it was significantly lower for variations at positions 16,051 and 207. Any variation at positions 152, 207 and 513 significantly decreased COX1 expression while those at positions 16,051 and 152 attenuated ATP6 expression. This first study evaluated type and overall pattern of D-loop variations in AML, and also showed that some of these variations in D loop region might have an effect on the mitochondrial-encoded genes which is new and valuable information in AML genomics.

Cytogenetic Profiles of 472 Indian Children with Acute Myeloid Leukemia

OBJECTIVE

To analyze the cytogenetic abnormalities of a large cohort of consecutive pediatric Acute Myeloid Leukemia (AML) patients, treated on a uniform protocol.

DESIGN

Review of case records.

SETTING

Pediatric Cancer Center of tertiary care hospital between June 2003 and June 2016.

PARTICIPANTS

617 consecutive de novo pediatric AML patients were screened and 472 patients were found eligible. Eligibility criteria included non M3 patients, successful cytogenetic profile and availability of complete records.

MAIN OUTCOME MEASURE

Cytogenetic profile.

RESULTS

Gum-hypertropy, chloromas and rate of complete remission were significantly different between European Leukemia Network classification (ELN) cytogenetic risk groups (P<0.01). t (8;21) (141, 29.8%), loss of Y chromosome (61,12.9%) and trisomy 8 (39, 8.3%) were the most common abnormalities. Among the chromosomal gains, trisomy 8 and trisomy 21 (both P<0.01) were significantly different among the three ELN risk groups. Among the chromosome losses, monosomy 5, 7 (both P<0.01) and 9 (P=0.03), loss of X and loss of Y (both P<0.01) were statistically different amongst three cytogenetic risk groups. Event-free survival (P<0.01) and overall survival (P<0.01) were found to be significantly different among the three risk groups.

CONCLUSIONS

The higher frequency of t (8; 21) and its association with chloroma in Indian pediatric patients is different from other studies around the world.

Serum Levels of Neuroactive Steroids in First-episode Antipsychotic-naïve Schizophrenic Patients and Its Correlation with Aggression: A Case-control Study

BACKGROUND

The evidence of hypothalamic-pituitary-adrenal axis dysfunction in schizophrenia has been reviewed in the context of the stress-diathesis model. Overactivation of this axis leads to altered blood levels of cortisol and dehydroepiandrosterone sulfate (DHEA-S). These neurosteroids in turn act on the hippocampus and interact with gamma-aminobutyric acid and N-methyl-D-aspartate receptors leading to neurotoxicity and may be involved in the neurobiology of aggression. This study aimed to explore the blood level of these neurosteroids and ascertain its correlation with state aggression and psychopathology in first-episode antipsychotic-naïve schizophrenic patients.

METHODS

A total of 30 patients with first-episode schizophrenia along with 20 age- and gender-matched healthy controls participated in the study. Both groups were subjected to serum cortisol and DHEA-S measurement after assessment of psychopathology and aggression on a standardised psychometric scale.

RESULTS

Serum DHEA-S level was significantly higher in the patient group (p = 0.001). No difference was noted between males and females in the patient group (p = 0.93) but female controls had a significantly lower serum DHEA-S level than male controls (p < 0.01). Serum DHEA-S inversely correlated with scores on Modified Overt Aggression Scale (p = 0.01) but not with Positive and Negative Syndrome Scale (p = 0.39) or Clinical Global Impression Scale (p = 0.28).

CONCLUSION

The first-episode antipsychotic-naïve schizophrenic patients showed a significantly higher blood level of DHEA-S compared with healthy controls. Serum DHEA-S level has an inverse relationship with aggression and may serve as a biological adaptive mechanism to antagonise the neuronal damage caused by cortisol.

Intra-abdominal pressure and intra-abdominal hypertension in critically ill obstetric patients: a prospective cohort study

BACKGROUND

Critically ill obstetric patients may have risk factors for intra-abdominal hypertension. This study evaluated the intra-abdominal pressure and its effect on organ function and the epidemiology of intra-abdominal hypertension.

METHODS

Obstetric patients admitted to an Intensive Care Unit, with an anticipated stay greater than 24hours, were included. Intra-abdominal pressure was measured daily via a Foley catheter, based on intravesical pressure.

RESULTS

One-hundred-and-one patients were enrolled. The intra-abdominal pressure was 5-7mmHg in 34%; 7-12mmHg in 60%; and ≥12mmHg (intra-abdominal hypertension) in 6%. All six patients with intra-abdominal hypertension were pregnant at the time of admission. The intra-abdominal pressure in four patients normalized to <12mmHg following delivery, but in the remaining two it persisted ≥12mmHg and both these patients died. Correlation between intra-abdominal pressure and organ dysfunction was weak (r=0.211). Statistical comparison between patients with and without intra-abdominal hypertension for risk factors, daily intra-abdominal pressures, and Sequential Organ Failure Assessment score could not be done due to the disproportionately small number of patients with intra-abdominal hypertension as opposed to those without (6 versus 95). Intra-abdominal pressure did not significantly differ between survivors and non-survivors (8.5±1.1 vs 7.9±1.7mmHg, P=0.079).

CONCLUSIONS

The incidence of intra-abdominal hypertension in critically ill obstetric patients was lower than previously defined for mixed Intensive Care Unit populations, with an association with the pregnant state. Normalization of intra-abdominal pressure after delivery was associated with better survival. There was no correlation between intra-abdominal pressure and organ function or mortality.

Adiponectin correlates with obesity: A study of 159 childhood acute leukemia survivors from India

BACKGROUND

Acute lymphoblastic leukemia survivors are predisposed to obesity. However, the exact underlying mechanisms are not known.

AIMS

The study was done to assess the role of biomarkers of obesity in acute leukemia survivors.

SETTINGS AND DESIGNS

This is a cross-sectional study conducted at All India Institute of Medical Sciences in survivors of acute leukemia who had completed treatment at least 1 year before enrollment in this study.

MATERIALS AND METHODS

Obesity was studied by determining the body mass index. Potential biomarkers were studied by assessing serum leptin, resistin, and adiponectin by enzyme-linked immunosorbant assay, and the results were compared in obese versus nonobese survivors.

STATISTICAL ANALYSIS

Descriptive analysis for baseline demographic factors and Student's t-test for comparing the mean levels of biomarkers among the obese and nonobese survivors.

RESULTS

One hundred and fifty-nine acute leukemia patients were enrolled in this study with a median follow-up of 36.8 months. The median age was 10 (range: 3-18) years, and 123 (77.3%) patients were males. The overall prevalence of overweight/obesity was 26.4%, and this was similar in acute myeloid leukemia and acute lymphoblastic leukemia sub-groups (26.2% vs. 27.3%, P = 0.9). Mean serum leptin and resistin were similar in obese and nonobese leukemia survivors (3.7 vs. 2.85 pg/mL, P = 0.064; 8.01 vs. 9.33 ng/mL, P = 0.36). However, mean serum adiponectin was significantly lower in obese leukemia survivors (7.97 vs. 11.5 μg/mL, P = 0.023).

CONCLUSIONS

Obese leukemic survivors had lower serum adiponectin levels than nonobese survivors. However, serum resistin and leptin levels were similar in the two groups.

Comparative Study of Neurological Soft Signs in Patients with Schizophrenia or Obsessive-compulsive Disorder, and Healthy Controls

OBJECTIVE

The primary objective of this study was to examine neurological soft signs in patients with obsessive-compulsive disorder compared with patients with schizophrenia and a control group in the Indian setting. The secondary objective was to find any correlation between age at onset and neurological soft signs scores, as well as that between severity of obsessive-compulsive disorder symptoms (total Yale-Brown Obsessive Compulsive Scale score) and neurological soft signs scores.

METHODS

This was a cross-sectional hospital-based study of 135 individuals (45 patients with schizophrenia, 45 patients with obsessive-compulsive disorder who were attending the psychiatric outpatient department of Sawai Man Singh Medical College, Jaipur, India, and 45 matched healthy controls) from 20 June 2013 to 22 December 2014. After applying strict inclusion and exclusion criteria, the participants completed the study instruments (Cambridge Neurological Inventory [Part 2] and Yale-Brown Obsessive Compulsive Scale). Their socio-demographic data were also recorded.

RESULTS

The neurological soft signs total score and domain scores (motor coordination, sensory integration, and disinhibition) were significantly higher in patients with schizophrenia (p < 0.05) than in the obsessive-compulsive disorder group or the control group. The obsessive-compulsive disorder group did not significantly differ from the control group in terms of neurological soft signs scores. No correlation was found between neurological soft signs scores and age at onset as well as that between neurological soft signs scores and total Yale-Brown Obsessive Compulsive Scale score.

CONCLUSION

Neurological soft signs assessed by the Cambridge Neurological Inventory and Yale-Brown Obsessive Compulsive Scale, which discriminate patients with schizophrenia from controls, appear to be relatively specific to schizophrenia. Further studies are required to explore neurological soft signs in patients with obsessive-compulsive disorder.

Redesigning services for the management of vitreomacular traction and macular hole

Vitreomacular traction (VMT) and VMT with macular hole (MH) are serious conditions, being associated with visual disturbance, for example, metamorphopsia, and diminished visual acuity (VA). Pars plana vitrectomy is the routine treatment for symptomatic VMT and VMT+MH. However, ocriplasmin has demonstrated favourable efficacy and safety in specific patient groups with VMT/MH and is now recommended as a treatment option for certain patients by the National Institute of Health and Care Excellence. This means that services for managing patients with VMT/MH may need to be revised, as patients can now potentially receive treatment earlier in the course of the disease. VMT triage clinics could provide a more efficient way of managing VMT/MH patients. Patient assessment should always include high-definition optical coherence tomography, as this is the most accurate means of assessing abnormalities in the vitreoretinal (VR) interface, and an accurate measurement of best-corrected VA. It has been proposed that patients with VMT+MH be managed as a routine 6-week referral, with the complete patient journey—from initial referral to treatment—taking no longer than 6 months. It is important that patients are entered onto VR surgical lists so that there is no delay if ocriplasmin treatment is unsuccessful. Patients will need appropriate counselling about the expected outcomes and possible side effects of ocriplasmin treatment. One-year follow-up data should be collected by treatment centres in order to evaluate the new VMT service.

Onset of acute and transient psychotic disorder in India: a study of socio-demographics and factors affecting its outcomes

OBJECTIVE

Acute and transient psychotic disorder has been accepted as a distinct diagnostic entity in the ICD-10. However, there are few studies delineating its demographics and factors affecting its outcome. This study aimed to examine the socio-demographic profile of patients with acute and transient psychotic disorder and the variables associated with the onset of illness and their effect on illness outcome in an Indian setting.

METHODS

This was a retrospective study in which case notes of patients admitted from 1 January to 31 December 2012 and diagnosed with acute and transient psychotic disorder (according to the ICD-10 diagnostic criteria) were analysed. Socio-demographic variables and variables associated with the onset of illness were noted. Duration of hospital stay was used as a proxy measure for clinical outcome.

RESULTS

A total of 185 patient records were analysed. Overall, 49% of the patients were males and 51% were females. Most of the cases (60%) were aged between 20 and 39 years. The majority was married, unemployed, educated up to middle school, living in a nuclear family, and had a rural background. Age (p = 0.05) and marital status (p = 0.03) significantly affected the outcome. Overall, 46% of the patients had stress as a precipitating factor, 27% reported substance use, and 23% had a family history of psychiatric illness prior to the onset of their illness. The onset of illness was from May to October in 54% of the patients, with the duration of untreated illness ranging from 7 to 15 days in 38% of the patients. The clinical outcome was significantly affected by duration of untreated illness (p = 0.05).

CONCLUSIONS

Acute and transient psychotic disorders show slight female preponderance and occur in early adulthood. There is no precipitating stress in most cases and shorter duration of untreated illness predicts favourable clinical outcome.

Injection Molding of Long Fiber Reinforced Thermoplastic Composites

Long fiber reinforced thermoplastic composites are one of the fastest growing segments experiencing 30% growth per year, over the last decade. This study describes the development of long fiber reinforced thermoplastic (LFRT) composites and the effect of fiber length on mold and process parameters of injection molding process. LFRT pellets of different sizes were prepared by an extrusion process using a specially designed impregnation die and palletized into different lengths. These pellets were injection molded to develop LFRT composites. Fiber length distributions were analyzed using a profile projector and an image analyzer software system. Maleic anhydride grafted polypropylene (MA-g-PP) was added to improve the adhesion between glass fibers and polypropylene. Improvement in mechanical properties were analyzed for different pellet sizes with different fiber content for long fiber reinforced polypropylene (LFPP) and long fiber reinforced polyamide (LFPA) composite.

Epidural volume extension: a review

Epidural volume extension is a technical modification of the combined spinal epidural block. It involves the epidural injection of normal saline or a small volume of local anaesthetic after an intrathecal injection, aiming to augment the post-spinal sensory level. Although the consequent sensory block augmentation has been adequately documented, the probable factors influencing epidural volume extension and its implications for clinical practice are not well defined. This article reviews published literature relating to the probable factors affecting epidural volume extension, its clinical implications, case reports of its successful clinical application and summarises its unexplored effects.