Effects of bumetanide on neonatal seizures: A systematic review of animal and human studies

BACKGROUND

Bumetanide, an inhibitor of the sodium-potassium-chloride cotransporter-1, has been suggested as an adjunct to phenobarbital for treating neonatal seizures.

METHODS

A systematic review of animal and human studies was conducted to evaluate the efficacy and safety of bumetanide for neonatal seizures. PubMed, Embase, CINAHL and Cochrane databases were searched in March 2023.

RESULTS

26 animal (rat or mice) studies describing 38 experiments (28 in-vivo and ten in-vitro) and two human studies (one RCT and one open-label dose-finding) were included. The study designs, methods to induce seizures, bumetanide dose, and outcome measures were heterogeneous, with only 4/38 experiments being in animal hypoxia/ischaemia models. Among 38 animal experiments, bumetanide was reported to have antiseizure effects in 21, pro-seizure in six and ineffective in 11. The two human studies (n = 57) did not show the benefits of bumetanide as an add-on agent to phenobarbital in their primary analyses, but one study reported benefit on post-hoc analysis. Overall, hearing impairment was detected in 5/37 surviving infants in the bumetanide group vs. 0/13 in controls. Four of the five infants with hearing impairment had received aminoglycosides concurrently. Other adverse effects reported were diuresis, mild-to-moderate dehydration, hypotension, and electrolyte disturbances. The studies did not report on long-term neurodevelopment. The certainty of the evidence was very low.

CONCLUSION

Animal data suggest that bumetanide has inconsistent effects as an antiseizure medication in neonates. Data from human studies are scarce and raise some concerns regarding ototoxicity when given with aminoglycosides. Well conducted studies in animal models of hypoxic-ischaemic encephalopathy are urgently needed. Future RCTs, if conducted in human neonates, should have an adequate sample size, assess neurodevelopment, minimize using aminoglycosides, be transparent about the potential ototoxicity in the parent information sheet, conduct early hearing tests and have trial-stopping rules that include hearing impairment as an outcome.

Examining the interseasonal resurgence of respiratory syncytial virus in Western Australia

BACKGROUND

Following a relative absence in winter 2020, a large resurgence of respiratory syncytial virus (RSV) detections occurred during the 2020/2021 summer in Western Australia. This seasonal shift was linked to SARS-CoV-2 public health measures. We examine the epidemiology and RSV testing of respiratory-coded admissions, and compare clinical phenotype of RSV-positive admissions between 2019 and 2020.

METHOD

At a single tertiary paediatric centre, International Classification of Diseases, 10th edition Australian Modification-coded respiratory admissions longer than 12 hours were combined with laboratory data from 1 January 2019 to 31 December 2020. Data were grouped into bronchiolitis, other acute lower respiratory infection (OALRI) and wheeze, to assess RSV testing practices. For RSV-positive admissions, demographics and clinical features were compared between 2019 and 2020.

RESULTS

RSV-positive admissions peaked in early summer 2020, following an absent winter season. Testing was higher in 2020: bronchiolitis, 94.8% vs 89.2% (p=0.01); OALRI, 88.6% vs 82.6% (p=0.02); and wheeze, 62.8% vs 25.5% (p<0.001). The 2020 peak month, December, contributed almost 75% of RSV-positive admissions, 2.5 times the 2019 peak. The median age in 2020 was twice that observed in 2019 (16.4 vs 8.1 months, p<0.001). The proportion of RSV-positive OALRI admissions was greater in 2020 (32.6% vs 24.9%, p=0.01). There were no clinically meaningful differences in length of stay or disease severity.

INTERPRETATION

The 2020 RSV season was in summer, with a larger than expected peak. There was an increase in RSV-positive non-bronchiolitis admissions, consistent with infection in older RSV-naïve children. This resurgence raises concern for regions experiencing longer and more stringent SARS-CoV-2 public health measures.

An integrative model of prostate cancer interaction with the bone microenvironment

Despite advanced efforts in early diagnosis, aggressive surgical treatment, and use of targeted chemotherapies, the prognosis for many cancers is still dismal. This emphasizes the necessity to develop new strategies for understanding tumor growth and metastasis. Here we use a systems approach that combines mathematical modeling and numerical simulation to develop a predictive computational model for prostate cancer and its subversion of the bone microenvironment. This model simulates metastatic prostate cancer evolution, progressing from normal bone and hormone levels to quantifiable diseased states. The simulations clearly demonstrate phenomena similar to those found clinically in prostate cancer patients. In addition, the major prediction of this model is the existence of low and high osteogenic states that are markedly different from one another. The existence and potential realization of these steady states appear to be mediated by the Wnt signaling pathway and by the effects of PSA on TGF-β, which encourages the bone microenvironment to evolve. The model is used to explore several potential therapeutic strategies, with some potential drug targets showing more promise than others: in particular, completely blocking Wnt and greatly increasing DKK-1 had significant positive effects, while blocking RANKL did not improve the outcome.

Ab initio calculation of the low-lying electronic states of the ZrN molecule

An ab initio calculation of the low-lying electronic states of zirconium nitride (ZrN) were performed by using a complete active space self-consistent field with multireference single and double excitation configuration interaction (MRSDCI). The potential energy curves of 21 low-lying electronic states of the ZrN molecule with different spin and spatial symmetries, in the representation 2s+1Λ(+/−) and below 30 000 cm–1, were identified. The harmonic frequency (ωe), the equilibrium internuclear distance (Re), the rotational constants (Be), the electronic energy with respect to the ground state (Te), and the permanent dipole moment (µ) were calculated for the considered electronic states. The comparison of these values with those available in the literature shows a very good agreement with either theoretical or experimental data. Fifteen new electronic states were studied here for the first time.

A low residue nutritive supplement as an alternative to feed withdrawal in broilers: efficacy for gastrointestinal tract emptying and maintenance of live weight prior to slaughter

Experiments were conducted to evaluate the production response to a solid phase, nutritive supplement used as an alternative to feed withdrawal in broiler chickens and its effect on gastrointestinal tract (GIT) residue. Three treatments were applied: a conventional 12-h feed withdrawal (control); provision of a highly digestible, carbohydrate-based feed withdrawal supplement (FWS) with no added protein source (FWS0); and provision of FWS containing 16% CP as a highly digestible protein source (FWS16). Both FWS treatments were designed to be highly and rapidly soluble, were formulated to result in nominally lower GIT residues, and were withdrawn for only 3 h prior to slaughter. Visual assessment of segments of the GIT at slaughter indicated no significant differences among treatments in the degree of emptiness of the crop, gizzard, and colon, whereas intestinal contents of both FWS groups were less (P < 0.05) than those of the control group. With or without prior acclimation to supplements, live weight losses for both FWS groups were consistently and significantly less than for the control group (P < 0.05). In birds acclimated to the supplement, hot eviscerated and chilled carcass weights and deboned breast meat yield were greater for FWS16 than for the control group (P < 0.05). Carcass water uptake during chilling was similar or lower for FWS treatments compared to controls so that the effect of supplement on improving product yield was not due to excessive water uptake. These data indicate that the provision of a highly digestible feed withdrawal supplement enhanced lower GIT emptying, reduced live weight loss, and in some instances improved product yield without the need for a prolonged period of feed withdrawal.

Oral lavage with polyethylene glycol reduces microbial colonization in the gastrointestinal tract of broilers

Oral lavage of 7-wk-old broiler chickens with polyethylene glycol (PEG) was conducted to induce rapid evacuation of the gastro-intestinal tract (GIT) before processing. Three groups of birds were fed ad libitum (FF), subjected to feed withdrawal 12 h before processing (FW), or received 115 mL of PEG by oral lavage 3 h before processing (PEG(L)). The crop, a section of small intestine, and the right cecum were aseptically collected for determination of contents and Gram-negative bacilli (GNB) counts. The PEG(L) effectively cleansed the upper GIT and intestine of treated birds within 3 h before processing. However, the ceca were not completely empty for all the birds subjected to PEG(L). The PEG(L) group had a significantly lower crop and cecal GNB concentrations than the FW group. Birds on FW and PEG(L) treatments had significantly lower GNB concentrations in the small intestine than FF birds. Polyethylene glycol resulted in complete evacuation of the upper GIT, as well as the intestine, within 3 h of use, and significantly reduced GNB concentrations.

A time-to-treatment analysis in the medicine versus angiography in thrombolytic exclusion (MATE) trial

Patients with acute coronary syndromes who are considered ineligible for thrombolytic therapy are at high risk of recurrent ischemia and death. This trial randomized 201 patients to triage angiography in the first 24 hours of hospital admission versus conventional medical care. Of the 165 patients who underwent angiography that was either protocol-driven or on the basis of physician preference, those who underwent angiography within 6 hours of symptom onset had a reduction in early and late adverse events. The rates of in-hospital recurrent ischemia were 15.4%, 15.4%, 17.5%, 32.4%, and 38.5%, respectively (P = 0.01 for trend), and rates of cumulative recurrent myocardial infarction or death were 0%, 12.8%, 10.0%, 11.8%, and 7.7%, respectively (P = 0.48 for trend) for patients who underwent angiography at 0-6, 6-12, 12-24, 24-48, and over 48 hours, respectively from symptom onset. Future trials of invasive versus conservative therapy should focus on performing angiography within 6 hours of symptom onset.

Metabolic Studies on Lean and Fat Pekin Ducks Selected for Breast Muscle Thickness Measured by Ultrasound Scanning

Female Pekin ducks selected for high (lean) or low (fat) breast muscle:total breast thickness ratio (MT:TOT), measured with ultrasound scanning, were used in metabolic studies to determine the metabolic differences and assess the effects of feed withdrawal and refeeding on plasma parameters. Lean and fat ducks had similar body weight changes throughout the studies. Lean ducks had significantly lower fat and higher CP and ash carcass contents. They also had higher (P < 0.05) plasma glucose after feed withdrawal but less (P < 0.05) plasma glucose after feeding. Fat ducks had similar plasma triglycerides (TG) after feed withdrawal but higher (P < 0.05) TG concentration after feeding and higher (P < 0.05) plasma uric acid than the lean females after feeding. Feed deprivation resulted in higher (P < 0.05) plasma cholesterol than did feeding. Lean ducks fed the test diet retained more (P < 0.05) N than the fat birds. Lean and fat Pekin ducks had similar (P > 0.05) AME, AMEn, TME, and TMEn. Lean ducks lost less (P < 0.05) N than fat birds. Plasma cholesterol was not significantly correlated (P = 0.06) with nitrogen retention (NR); NR was negatively correlated (P < 0.05) with plasma TG, and TG was positively correlated (P < 0.05) with total energy excreted. There was a positive correlation (P < 0.05) between MT:TOT and NR. The MT:TOT correlated (P < 0.05) negatively with carcass fat, and positively with carcass CP and plasma insulin-like growth factor I (IGF-I) concentration. The results we obtained demonstrate the usefulness of ultrasound scanning in live bird selection for leanness and greater breast muscle thickness and are related to metabolic differences between lean and fat female Pekin ducks selected for high or low MT:TOT ratios.

Comparison of growth performance, carcass yield and composition, and fatty acid profiles of Pekin and Muscovy ducklings fed diets based on food wastes

Pekin and Muscovy male ducklings were raised on diets based on food wastes. Three feeding systems were offered: commercial pellets (control), partial food waste (PFW) and 100% food waste (FW). For the starting, growing and finishing periods, respectively, the control system provided 25, 23 and 21% crude protein (CP) on a dry matter (DM) basis. The two experimental systems each had a dry pelleted diet and a wet mash diet offered free choice. The PFW system had two rations for the dry diet containing 23 and 22% CP for the starting and growing–finishing periods, respectively, whereas the wet diet had a single ration with 17% CP on a DM basis. The FW also had two forms of diets: dry pellets (18% CP) and wet mash (20% CP). The PFW ducks had higher (P < 0.05) body weights than those of the control system. Both breeds consumed less feed of PFW and FW than those on the control. Feed efficiency was significantly improved for PFW and FW relative to control for both breeds. The birds fed food waste diets consumed higher proportions of fat and less protein. Pekins had higher (P < 0.05) content of skin and fat, whereas the Muscovies had a higher (P < 0.05) content of meat and bone. Both breeds had a preference for wet over dry diets as a percentage of the total feed consumption. Fatty acid profiles of the subcutaneous fat showed significant breed but no feeding system differences. These results suggest industrial food wastes have potential nutritional value as alternative feedstuffs. Key words: Food waste, duck, performance, carcass, fatty acid

Impaired culprit vessel flow in acute coronary syndromes ineligible for thrombolysis

The majority of patients with acute myocardial infarction and other acute coronary syndromes (ACS) are considered ineligible for thrombolysis and do not routinely receive reperfusion therapy. We hypothesized that predictors and outcomes of angiographically impaired culprit vessel flow can be identified and compared. This trial evaluated the outcomes following triage angiography in acute coronary syndromes ineligible for thrombolytic therapy. Eligible patients (n=201) with<24 hours of symptoms were randomized to early triage angiography and subsequent therapies based on the angiogram versus conventional medical therapy. This analysis was performed in 165 patients, from experimental and control arms, in whom angiography was performed on the index hospitalization with the outcome of interest being target vessel flow (Thrombolysis In Myocardial Infarction [TIMI] grades 0 to 2) on initial angiography. Patients with and without impaired culprit lesion flow were similar with respect to age, gender, diabetes, and prior coronary disease. A family history of premature coronary disease was more common in those with impaired flow, 50.0 versus 28.5% (p=0.02). Abnormal culprit vessel flow was found in 19.2% of patients who underwent angiography within 6 hours of symptom onset; however, after 24 hours this rate was reduced to 11.7%. Impaired culprit lesion flow can be expected in approximately 20% of patients presenting with ACS who are ineligible for reperfusion therapy by conventional guidelines and therefore represents an opportunity for early intervention within 6 hours of the onset of symptoms in these patients.

Comparative performance, blood chemistry, and carcass composition of two lines of Pekin ducks reared mixed or separated by sex

Male and female Pekin ducks selected (F2 generation) for greater breast muscle thickness (MT) and an unselected control (C) were used in this study under mixed- or separated-sex rearing. Ducks in the separated-sex program had significantly higher body weights than the birds in the mixed-sex program. The ducks selected for greater breast muscle thickness exhibited superior (P < 0.05) body weight up to 42 d of age. Males from the MT line reached market weight at 6 wk, but the breast muscle thickness, measured by ultrasound scanning, improved significantly from 6 to 7 wk of age. Males had greater (P < 0.05) breast muscle thickness than females. At both ages and for both sexes, the MT line had greater (P < 0.05) breast muscle thickness than the C line. The MT ducks consumed more (P < 0.05) feed up to 6 wk, but no significant difference was found in cumulative feed consumption at 7 wk, and the lines did not differ (P > 0.05) in feed:gain ratio. Males had significantly higher cumulative feed consumption at 6 wk but had a more desirable (P < 0.05) feed:gain ratio than females at 7 wk. Compared with females from the C line, MT females had significantly higher carcass yield, higher body protein, and lower fat. The MT females had higher plasma glucose and lower uric acid than the C females, but no significant difference was found between the MT and C lines for plasma triglycerides and total cholesterol. The results of this study support the utility of ultrasound scanning in duck selection, the separated rearing of ducklings, and the possibility of reducing the slaughter age of lean males.

Effects of line, dietary protein, sex, age, and feed withdrawal on insulin-like growth factor-I in White Pekin ducks

Three experiments were conducted to determine and characterize plasma insulin-like growth factor-I (IGF-I) concentrations in Pekin ducks. Plasma IGF-I in Pekin ducks was assayed in a heterologous radioimmunoassay for human IGF-I. When treated with acid, the response dose of duck IGF-I was parallel to that of human recombinant (r) IGF-I. The effect of line (greater breast muscle thickness vs. control) was determined in Experiment 1 in female ducks. The ducks with greater breast muscle thickness had higher (P<0.05) plasma IGF-I concentrations than the control ducks. In Experiment 2, the effects of dietary protein, sex, and age were examined from 42 to 49 d of age. Three dietary programs that differ in dietary crude protein were used in this experiment. Ducks on the high protein program had (P<0.05) higher plasma IGF-I concentrations than ducks on either medium or low protein programs. Males exhibited higher (P<0.05) IGF-I than females. Plasma IGF-I concentrations decreased with age from 42 to 49 d. In Experiment 3, the effects of selection criterion (high or low breast muscle thickness to total breast thickness ratio) and the feed-deprived or fed state were studied in female Pekin ducks. The high ratio ducks were more affected by feed deprivation. These ducks had similar plasma IGF-I concentrations to low ratio ducks during feed withdrawal, but had higher (P<0.05) concentrations when fed. These data contribute to an understanding of the influence of IGF-I on metabolism and will be of value to the improvement of lean Pekin duck production.

Nutrient digestibility in food waste ingredients for Pekin and Muscovy ducks

Food wastes are valuable resources to be recycled into new added-value products through animal production. The determination of energy and digestibility values of these wastes is essential for feed formulation. Corn, soybean meal (SBM), and a total of nine industrial food waste ingredients were tested in a comparative metabolic study in Pekin and Muscovy ducklings at two different ages during growth. The "precision-feeding" technique was employed to establish DM, fat, and fiber digestibility as well as retention of N and energy (AME, AMEn in Pekins; and AME, AMEn, TME, TMEn in Muscovies) for the 11 ingredients. For Pekin at 3 wk of age, the AMEn of peanuts, tofu, pogo, granola, waste diet, bread, corn, SBM, okara, and brewers grains were 5,141, 4,019, 3,971, 3,908, 3,141, 2,279, 1,572, and 1,442 kcal/kg, respectively. For Pekin at 6 wk of age, the AMEn of peanuts, pogo, tofu, granola, waste diet, bread, corn, SBM, and okara were 5,340, 4,327, 4,254, 4,079, 3,567, 3,302, 3,201, 2,416, and 1,562 kcal/kg, respectively. For Muscovy at 7 wk of age, the TMEn of peanuts, pogo, granola, waste diet, corn, tofu, bread, SBM, okara, and peanut skin were 5,207, 4,321, 4,057, 3,733, 3,233, 3,180, 3,084, 2,236, 1,575, and 904 kcal/kg, respectively. For Muscovy at 11 wk of age, the TMEn of peanuts, pogo, granola, tofu, waste diet, corn, bread, SBM, okara, and brewers grains were 5,077, 4,137, 4,025, 3,921, 3,586, 3,254, 3,123, 2,245, 2,007, and 1,392 kcal/kg, respectively. Nitrogen retention was significantly (P < 0.05) higher for SBM, tofu, okara, pogo, peanuts, and the food waste diet and lower for bread, corn, granola, brewers grains, and peanut skin. Dry matter digestibility was high for granola, pogo, corn, bread, and the food waste diet. Fat digestibility was generally the same for all the ingredients and was consistently over 97%. Bread neutral detergent fiber (NDF) was significantly (P < 0.05) the most digestible (88.92% NDF digestibility), as it consisted of 96.29% hemicellulose, whereas okara NDF was significantly (P < 0.05) the least digestible (26.94% NDF digestibility) and contained only 14.38% hemicellulose. Peanut skins and SBM with 30% hemicellulose showed only slightly higher digestibilities of NDF. The results of this study establish reliable data for formulation of duck diets using the tested industrial food waste ingredients as well as corn and SBM in both Pekin and Muscovy ducklings at two different ages during growth to market weight.

A prospective randomized trial of triage angiography in acute coronary syndromes ineligible for thrombolytic therapy. Results of the medicine versus angiography in thrombolytic exclusion (MATE) trial

OBJECTIVES

The purpose of this study was to determine if early triage angiography with revascularization, if indicated, favorably affects clinical outcomes in patients with suspected acute myocardial infarction who are ineligible for thrombolysis.

BACKGROUND

The majority of patients with acute myocardial infarction and other acute coronary syndromes are considered ineligible for thrombolysis and therefore are not afforded the opportunity for early reperfusion.

METHODS

This multicenter, prospective, randomized trial evaluated in a controlled fashion the outcomes following triage angiography in acute coronary syndromes ineligible for thrombolytic therapy. Eligible patients (n=201) with <24 h of symptoms were randomized to early triage angiography and subsequent therapies based on the angiogram versus conventional medical therapy consisting of aspirin, intravenous heparin, nitroglycerin, beta-blockers, and analgesics.

RESULTS

In the triage angiography group, 109 patients underwent early angiography and 64 (58%) received revascularization, whereas in the conservative group, 54 (60%) subsequently underwent nonprotocol angiography in response to recurrent ischemia and 33 (37%) received revascularization (p=0.004). The mean time to revascularization was 27+/-32 versus 88+/-98 h (p=0.0001) and the primary endpoint of recurrent ischemic events or death occurred in 14 (13%) versus 31 (34%) of the triage angiography and conservative groups, respectively (45% risk reduction, 95% CI 27-59%, p=0.0002). There were no differences between the groups with respect to initial hospital costs or length of stay. Long-term follow-up at a median of 21 months revealed no significant differences in the endpoints of late revascularization, recurrent myocardial infarction, or all-cause mortality.

CONCLUSIONS

Early triage angiography in patients with acute coronary syndromes who are not eligible for thrombolytics reduced the composite of recurrent ischemic events or death and shortened the time to definitive revascularization during the index hospitalization. Despite more frequent early revascularization after triage angiography, we found no long-term benefit in cardiac outcomes compared with conservative medical therapy with revascularization prompted by recurrent ischemia.

5-Methylphenazinium methylsulfate mediates cyclic electron flow and proton gradient dissipation in chromaffin-vesicle membranes

When 5-methylphenazinium methylsulfate and a reductant (ascorbate or NADH) are added together to a suspension of resealed chromaffin-vesicle membranes, the pH gradient (inside acidic) and the membrane potential (inside positive) established by the H(+)-translocating adenosine triphosphatase (ATPase) are rapidly dissipated. Dissipation of the pH gradient may be observed using either the optical probe acridine orange or the weak base methylamine. Dissipation of the membrane potential may be observed using the potential-dependent dye oxonol VI. A reductant and 5-methylphenazinium methylsulfate added in combination will also abolish a K+ diffusion potential across chromaffin-vesicle membranes but not across liposome membranes. 5-Methylphenazinium methylsulfate oxidizes cytochrome b561 in chromaffin-vesicle ghosts. Ascorbate readily reduces cytochrome b561, but reduction of cytochrome b561 by NADH is greatly enhanced in the presence of 5-methylphenazinium methylsulfate. These results are consistent with a mechanism in which proton gradient dissipation (a net efflux of H+) is caused by an influx of electrons through the membrane-protein cytochrome b561 coupled with an efflux of H carried by the reduced species 5-methyl-10-hydrophenazine. Although 5-methylphenazinium has been thought to accumulate within acidic vesicles as a weak base, this accounts for neither proton gradient dissipation nor for intravesicular accumulation of the compound.