Analysis of Factors Affecting Burns Mortality: A National Burn Centre Experience From Pakistan 2007-2021

Burns are a public health concern burdening the healthcare delivery system across the globe. Mortality rates are significant outcome parameters after a burn injury. The objective of the current study was to analyze the characteristics of the patients admitted to our burn care center and identify the factors related to mortality in the burn patients. This was a cross-sectional single-center study involving a retrospective analysis of mortality rates in burn patients over a period of 15 years from July 2007 to December 2021. During the study period, 7,866 burn patients were admitted to the ICU of the burn care center. Patients who died [Group 1] were compared to the group of survivors (control cases [Group 2]) to ascertain the contributing factors that might forecast a high risk for mortality. The mortality rate was calculated as 23.16% (1,822/7,866). The majority of the patients (both groups) had a total body surface area (TBSA) of >50% (p 0.001). The average duration of stay at the burn care center was 15.5 days for the survivors' group (Group 2) while it was 11.4 days for the patients who died (Group 1) during the course of their treatment. About 23.16% of all admitted patients died mostly from flame burns, and sepsis was the commonest cause of death. Patients with risk factors should be classified as high risk for mortality at the time of ICU admission. It is necessary to initiate educational and awareness programs for sensitization related to the prevention of burn injuries.

Pattern of Acute Adverse Transfusion Reactions in Patients With Burn Injuries: A Novel Initiative Towards Haemovigilance at the National Burn Centre of Pakistan

The transfusion of blood and blood components is a life-saving medical procedure, however, it is linked with adverse reactions to transfusions. Information about different types of adverse transfusion reactions (ATRs) will assist in their early identification and subsequent management, as well as in devising strategies to minimize the occurrence of adverse reactions related to blood component transfusion. The current study was therefore executed to analyze the pattern of ATRs in patients with burn injuries at a national burn center. This was a cross-sectional, prospective study involving an analysis of immediate ATRs from January 2020 to June 2021 (18 months). ATRs observed during the study period were documented and analyzed. During the study period, 2,220 units of blood and blood components were transfused to 1,075 burn patients (2.06 transfusions per patient). A total of 27 ATRs were recorded (1.21%). Allergic reactions were the commonest (55.55%) followed by febrile non-haemolytic transfusion reaction (37.03%). The mean volume of blood unit transfused, when the reactions were noted, was approximately 75 ml (range: 15-230 ml). The mean time at which transfusion reactions were noted was 17 min (range: 5-220 minutes). The ATRs were more common in patients with multiple transfusions compared to those receiving a single transfusion. The common adverse reactions were allergic and febrile non-haemolytic transfusion reactions. It is vital to report all transfusion reactions to the attached blood center and hospital transfusion committee (HTC) on standardized reporting forms. Continuous medical education through seminars and sensitization workshops will support consolidating haemovigilance systems.

International Nosocomial Infection Control Consortium (INICC) report, data summary of 45 countries for 2012-2017: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2012 to December 2017 in 523 intensive care units (ICUs) in 45 countries from Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, prospective data from 532,483 ICU patients hospitalized in 242 hospitals, for an aggregate of 2,197,304 patient days, were collected through the INICC Surveillance Online System (ISOS). The Centers for Disease Control and Prevention-National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI) were applied.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the medical-surgical ICUs, the pooled central line-associated bloodstream infection rate was higher (5.05 vs 0.8 per 1,000 central line-days); the ventilator-associated pneumonia rate was also higher (14.1 vs 0.9 per 1,000 ventilator-days,), as well as the rate of catheter-associated urinary tract infection (5.1 vs 1.7 per 1,000 catheter-days). From blood cultures samples, frequencies of resistance, such as of Pseudomonas aeruginosa to piperacillin-tazobactam (33.0% vs 18.3%), were also higher.

CONCLUSIONS

Despite a significant trend toward the reduction in INICC ICUs, DA-HAI rates are still much higher compared with CDC-NHSN's ICUs representing the developed world. It is INICC's main goal to provide basic and cost-effective resources, through the INICC Surveillance Online System to tackle the burden of DA-HAIs effectively.

Comparing ammonia diffusion in NH3-SCR zeolite catalysts: a quasielastic neutron scattering and molecular dynamics simulation study

The diffusion of ammonia in the small pore zeolite and potential commercial NH3-SCR catalyst levynite (LEV) was measured and compared with its mobility in the chabazite (CHA) topology (more established in NOx abatement catalysis), using quasielastic neutron scattering (QENS) and molecular dynamics (MD) simulations at 273, 323 and 373 K. The QENS experiments suggest that mobility in LEV is dominated by jump diffusion through the 8-ring windows between cages (as previously observed in CHA) which takes place at very similar rates in the two zeolites, yielding similar experimental self-diffusion coefficients (Ds). After confirming that the same characteristic motions are observed between the MD simulations and the QENS experiments on the picosecond scale, the simulations suggest that on the nanoscale, the diffusivity is higher by a factor of ∼2 in the CHA framework than in LEV. This difference between zeolites is primarily explained by the CHA cages having six 8-ring windows in the building unit, compared to only three such windows in the LEV cage building unit, thereby doubling the geometric opportunities to perform jump diffusion between cages (as characterised by the QENS experiments) leading to the corresponding increase in the MD calculated Ds. The techniques illustrate the importance of probing both pico- and nanoscale dynamics when studying intracrystalline diffusion in both NH3-SCR catalyst design, and in porous materials generally, where notable consistencies and differences may be found on either scale.

DFT calculation of oxygen adsorption on platinum nanoparticles: coverage and size effects

DFT calculations are used to simultaneously explore the effects of nanoparticle size and coverage for O adsorption on Pt nanoparticles.

Structural studies of substrate and product complexes of 5-aminolaevulinic acid dehydratase from humans,Escherichia coliand the hyperthermophilePyrobaculum calidifontis

A number of X-ray analyses of an enzyme involved in a key early stage of tetrapyrrole biosynthesis are reported. Two structures of human 5-aminolaevulinate dehydratase (ALAD), native and recombinant, have been determined at 2.8 Å resolution, showing that the enzyme adopts an octameric quaternary structure in accord with previously published analyses of the enzyme from a range of other species. However, this is in contrast to the finding that a disease-related F12L mutant of the human enzyme uniquely forms hexamers [Breiniget al.(2003),Nature Struct. Biol.10, 757–763]. Monomers of all ALADs adopt the TIM-barrel fold; the subunit conformation that assembles into the octamer includes the N-terminal tail of one monomer curled around the (α/β)8barrel of a neighbouring monomer. Both crystal forms of the human enzyme possess two monomers per asymmetric unit, termedAandB. In the native enzyme there are a number of distinct structural differences between theAandBmonomers, with the latter exhibiting greater disorder in a number of loop regions and in the active site. In contrast, the second monomer of the recombinant enzyme appears to be better defined and the active site of both monomers clearly possesses a zinc ion which is bound by three conserved cysteine residues. In native human ALAD, theAmonomer also has a ligand resembling the substrate ALA which is covalently bound by a Schiff base to one of the active-site lysines (Lys252) and is held in place by an ordered active-site loop. In contrast, these features of the active-site structure are disordered or absent in theBsubunit of the native human enzyme. The octameric structure of the zinc-dependent ALAD from the hyperthermophilePyrobaculum calidifontisis also reported at a somewhat lower resolution of 3.5 Å. Finally, the details are presented of a high-resolution structure of theEscherichia coliALAD enzyme co-crystallized with a noncovalently bound moiety of the product, porphobilinogen (PBG). This structure reveals that the pyrrole side-chain amino group is datively bound to the active-site zinc ion and that the PBG carboxylates interact with the enzymeviahydrogen bonds and salt bridges with invariant residues. A number of hydrogen-bond interactions that were previously observed in the structure of yeast ALAD with a cyclic intermediate resembling the product PBG appear to be weaker in the new structure, suggesting that these interactions are only optimal in the transition state.

Enhanced serelaxin signalling in co-cultures of human primary endothelial and smooth muscle cells

BACKGROUND AND PURPOSE

In the phase III clinical trial, RELAX-AHF, serelaxin caused rapid and long-lasting haemodynamic changes. However, the cellular mechanisms involved are unclear in humans.

EXPERIMENTAL APPROACH

This study examined the effects of serelaxin in co-cultures of human primary endothelial cells (ECs) and smooth muscle cells (SMCs) on cAMP and cGMP signalling.

KEY RESULTS

Stimulation of HUVECs or human coronary artery endothelial cells (HCAECs) with serelaxin, concentration-dependently increased cGMP accumulation in co-cultured SMCs to a greater extent than in monocultures of either cell type. This was not observed in human umbilical artery endothelial cells (HUAECs) that do not express the relaxin receptor, RXFP1. Treatment of ECs with l-N(G) -nitro arginine (NOARG; 30 μM, 30 min) inhibited serelaxin-mediated (30 nM) cGMP accumulation in HUVECs, HCAECs and co-cultured SMCs. In HCAECs, but not HUVECs, pre-incubation with indomethacin (30 μM, 30 min) also inhibited cGMP accumulation in SMCs. Pre-incubation of SMCs with the guanylate cyclase inhibitor ODQ (1 μM, 30 min) had no effect on serelaxin-mediated (30 nM) cGMP accumulation in HUVECs and HCAECs but inhibited cGMP accumulation in SMCs. Serelaxin stimulation of HCAECs, but not HUVECs, increased cAMP accumulation concentration-dependently in SMCs. Pre-incubation of HCAECs with indomethacin, but not l-NOARG, abolished cAMP accumulation in co-cultured SMCs, suggesting involvement of prostanoids.

CONCLUSIONS AND IMPLICATIONS

In co-cultures, treatment of ECs with serelaxin caused marked cGMP accumulation in SMCs and with HCAEC also cAMP accumulation. Responses involved EC-derived NO and with HCAEC prostanoid production. Thus, serelaxin differentially modulates vascular tone in different vascular beds.

Effect of graphene support on large Pt nanoparticles

Large scale DFT calculations of Pt nanoparticles supported on graphene explore the non-trivial interplay of size and support effects.

Signalling profiles of H3 relaxin, H2 relaxin and R3(BΔ23-27)R/I5 acting at the relaxin family peptide receptor 3 (RXFP3)

BACKGROUND AND PURPOSE

Relaxin family peptide receptor 3 (RXFP3) is expressed in brain areas important for processing sensory information and feeding, suggesting that it may be a target for anti-anxiety and anti-obesity drugs. We examined the effects of H3 relaxin, the biased agonist H2 relaxin and the antagonist, R3(BΔ23-27)R/I5, on RXFP3 signalling to establish their suitability as tools to assess the physiological roles of RXFP3.

EXPERIMENTAL APPROACH

The signalling profile of the RXFP3 ligands was determined using reporter gene assays, multiplexed signalling assays and direct examination of receptor-G protein and receptor-β-arrestin interactions using BRET.

KEY RESULTS

H2 relaxin activated p38MAPK and ERK1/2 with lower efficacy than H3 relaxin, but had similar efficacy for JNK1/2 phosphorylation. H2 or H3 relaxin activation of p38MAPK, JNK1/2 or ERK1/2 involved Pertussis toxin-sensitive G-proteins. R3(BΔ23-27)R/I5 blocked H3 relaxin AP-1 reporter gene activation, but not H2 relaxin AP-1 activation or H3 relaxin NF-κB activation. R3(BΔ23-27)R/I5 activated the SRE reporter, but did not inhibit either H2 or H3 relaxin SRE activation. R3(BΔ23-27)R/I5 blocked H3 relaxin-stimulated p38MAPK and ERK1/2 phosphorylation, but was a weak partial agonist for p38MAPK and ERK1/2 signalling. p38MAPK activation by R3(BΔ23-27)R/I5 was G protein-independent. H3 relaxin-activated RXFP3 interacts with Gαi2 , Gαi3 , Gαo A and Gαo B whereas H2 relaxin or R3(BΔ23-27)R/I5 induce interactions only with Gαi2 or Gαo B . Only H3 relaxin promoted RXFP3/β-arrestin interactions that were blocked by R3(BΔ23-27)R/I5.

CONCLUSION AND IMPLICATIONS

Understanding signalling profile of drugs acting at RXFP3 is essential for development of therapies targeting this receptor.

Serelaxin-mediated signal transduction in human vascular cells: bell-shaped concentration-response curves reflect differential coupling to G proteins

BACKGROUND AND PURPOSE

In a recently conducted phase III clinical trial, RELAX-AHF, serelaxin infusion over 48 h improved short- and long-term clinical outcomes in patients with acute heart failure. In this study we used human primary cells from the umbilical vasculature to better understand the signalling mechanisms activated by serelaxin.

EXPERIMENTAL APPROACH

We examined the acute effects of serelaxin on signal transduction mechanisms in primary human umbilical vascular cells and its chronic actions on markers of cardiovascular function and disease.

KEY RESULTS

The RXFP1 receptor, the cognate serelaxin receptor, was expressed at the cell surface in HUVECs and human umbilical vein smooth muscle cells (HUVSMCs), human umbilical artery smooth muscle cells (HUASMCs) and human cardiac fibroblasts (HCFs), but not human umbilical artery endothelial cells. In HUVECs and HUVSMCs, serelaxin increased cAMP, cGMP accumulation and pERK1/2, and the concentration-response curves (CRCs) were bell-shaped. Similar bell-shaped CRCs for cGMP and pERK1/2 were observed in HCFs, whereas in HUASMCs, serelaxin increased cAMP, cGMP and pERK1/2 with sigmoidal CRCs. Gαi/o and lipid raft disruption, but not Gαs inhibition, altered the serelaxin CRC for cAMP and cGMP accumulation in HUVSMC but not HUASMC. Longer term serelaxin exposure increased the expression of neuronal NOS, VEGF, ETβ receptors and MMPs (gelatinases) in RXFP1 receptor-expressing cells.

CONCLUSIONS AND IMPLICATIONS

Serelaxin caused acute and chronic changes in human umbilical vascular cells that were cell background dependent. Bell-shaped CRCs that were observed only in venous cells and fibroblasts involved Gαi/o located within membrane lipid rafts.

Relaxin-3 mRNA levels in nucleus incertus correlate with alcohol and sucrose intake in rats

BACKGROUND

Chronic alcohol intake produces multiple neuroadaptive changes, including up- and down-regulation of neuropeptides and receptors. There are widespread projections of relaxin-3 containing neurons to, and abundant relaxin family peptide 3 receptor (RXFP3) expression within, brain regions involved in modulating alcohol intake. Recently we demonstrated the involvement of relaxin-3/RXFP3 signalling in alcohol-seeking in rats; therefore in this study we examined whether relaxin-3 and/or RXFP3 expression were altered by chronic alcohol intake in alcohol-preferring iP rats.

METHODS

Expression of relaxin-3 mRNA in the hindbrain nucleus incertus and RXFP3 radioligand binding levels in discrete forebrain regions were investigated following voluntary intake of alcohol or sucrose for 12 weeks, with a 2 day washout, using quantitative in situ hybridisation histochemistry and in vitro receptor autoradiography, respectively, in cohorts of adult, male iP rats.

RESULTS

Levels of relaxin-3 mRNA in the hindbrain nucleus incertus were positively correlated with the level of intake of both alcohol (r(12)=0.59, p=0.03) and sucrose (r(7)=0.70, p=0.04) in iP rats. Dense binding of the RXFP3-selective radioligand, [(125)]-R3/I5, was detected in hypothalamic and extrahypothalamic sites, but no significant changes in the density of RXFP3 were observed in the brain regions quantified following chronic sucrose or ethanol intake.

CONCLUSIONS

Our findings suggest high endogenous relaxin-3 expression may be associated with higher intake of rewarding substances, rather than its expression being regulated in response to their intake, consistent with an active role for the relaxin-3/RXFP3 system in modulating ingestive and alcohol-related behaviours.

Contrasting views of animal healthcare providers on worm control practices for sheep and goats in an arid environment

A questionnaire survey was conducted to determine the worm control practices and anthelmintic usage of 150 key respondents involved in sheep and goat production in the arid Thal area of Pakistan. The information was collected by visiting farms, and interviewing the key respondents which included veterinary officers (n = 15), veterinary assistants (n = 51), traditional practitioners (n = 24), and small and large scale sheep/goat farm herders and owners (n = 60). Among all interviewed animal healthcare providers, the veterinary officers had the highest level of awareness of parasitic infection and advocated the use of modern available anthelmintics according to the predefined schedule. The farmers on the other hand, had the lowest level of knowledge about parasitic infections. They used modern anthelmintics at low frequencies (every six months) following an unusual practice of diluting the medicine. Veterinary assistants had a medium level of awareness about the parasitic infections using anthelmintic treatments when they deemed necessary rather than following a predefined treatment schedule. Traditional practitioners were also aware of parasitic infections and used traditional anthelmintics or a combination of the traditional and modern anthelmintics. The animal health providers had a different awareness and knowledge of parasitic infections which resulted in contrasting proposals for its' control. The farmers used worm control measures in accordance with their own views and those of animal healthcare advisors, combining modern and traditional treatments. This study provides the first insight into the differing views of those animal healthcare providers who form the basis for effective parasitic control within the sheep and goat industry of an arid region.

Estimation of growth curve parameters in Beetal goats

Abstract. Growth data from birth to one year of age on 120 Beetal goats, 30 animals on each farm, including Livestock Experiment Station (LES) Rakh Kheirewala, LES Rakh Ghulaman, LES Alladad and LPRI Bahadurnagar, Okara, Pakistan, were recorded and analysed for estimating growth curve parameters: predicted live weight, »a«, turning point of growth, »b« and rate of growth »k« by using Brody and Gompertz mathematical functions employing non-linear regression models. Estimates of the growth curve parameters »a«, »b« and »k« were 29.1, 0.916 and 0.108 for Brody and 23.4, 1.984 and 0.258 for Gompertz functions, respectively. The corresponding values of determination coefficient and mean absolute deviation for these models were 99.8 and 99.8 percent and 0.0061 and 0.0050, respectively. Flock significantly affected parameter »b« of Brody and Gompertz models. Sex did not affect any of the parameters in both models. Type of birth was a significant source of variation for parameter »b« in the Brody model. The determination coefficient showed that both the models efficiently explained the growth of Beetal kids.

Myocardial oxidative stress contributes to transgenic β₂-adrenoceptor activation-induced cardiomyopathy and heart failure

BACKGROUND AND PURPOSE

While maintaining cardiac performance, chronic β-adrenoceptor activation eventually exacerbates the progression of cardiac remodelling and failure. We examined the adverse signalling pathways mediated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and reactive oxygen species (ROS) after chronic β₂-adrenoceptor activation.

EXPERIMENTAL APPROACH

Mice with transgenic β₂-adrenoceptor overexpression (β₂-TG) and non-transgenic littermates were either untreated or treated with an antioxidant (N-acetylcysteine, NAC) or NADPH oxidase inhibitors (apocynin, diphenyliodonium). Levels of ROS, phosphorylated p38 mitogen-activated protein kinase (MAPK), pro-inflammatory cytokines and collagen content in the left ventricle (LV) and LV function were measured and compared.

KEY RESULTS

β₂-TG mice showed increased ROS production, phosphorylation of p38 MAPK and heat shock protein 27 (HSP27), expression of pro-inflammatory cytokines and collagen, and progressive ventricular dysfunction. β₂-adrenoceptor stimulation similarly increased ROS production and phosphorylation of p38 MAPK and HSP27 in cultured cardiomyocytes. Treatment with apocynin, diphenyliodonium or NAC reduced phosphorylation of p38 MAPK and HSP27 in both cultured cardiomyocytes and the LV of β₂-TG mice. NAC treatment (500 mg·kg⁻¹ ·day⁻¹) for 2 weeks eliminated the up-regulated expression of pro-inflammatory cytokines and collagen in the LV of β₂-TG mice. Chronic NAC treatment to β₂-TG mice from 7 to 10 months of age largely prevented progression of ventricular dilatation, preserved contractile function (fractional shortening 37 ± 5% vs. 25 ± 3%, ejection fraction 52 ± 5% vs. 32 ± 4%, both P < 0.05), reduced cardiac fibrosis and suppressed matrix metalloproteinase activity.

CONCLUSION AND IMPLICATIONS

β₂-adrenoceptor stimulation provoked NADPH oxidase-derived ROS production in the heart. Elevated ROS activated p38 MAPK and contributed significantly to cardiac inflammation, remodelling and failure.

Crystallization and preliminary X-ray diffraction analysis of the protease from Southampton norovirus complexed with a Michael acceptor inhibitor

Noroviruses are the predominant cause of human epidemic nonbacterial gastroenteritis. Viral replication requires a cysteine protease that cleaves a 200 kDa viral polyprotein into its constituent functional parts. Here, the crystallization of the recombinant protease from the Southampton norovirus is described. Whilst the native crystals were found to diffract only to medium resolution (2.9 Å), cocrystals of an inhibitor complex diffracted X-rays to 1.7 Å resolution. The polypeptide inhibitor (Ac-EFQLQ-propenyl ethyl ester) possesses an amino-acid sequence designed to match the substrate specificity of the enzyme, but was synthesized with a reactive Michael acceptor group at the C-terminal end.

Influence of Canola Meal-Based Diets Supplemented with Exogenous Enzyme and Digestible Lysine on Performance, Digestibility, Carcass, and Immunity Responses of Broiler Chickens

The response of broiler chickens to 2 levels of endo-1,4-beta xylanase and endo-1,3-beta glucanase combination (with and without), 3 levels of digestible Lys (0.8, 0.9, and 1.0%), and 2 levels of canola meal (CM; 20 and 30%) were evaluated in 2 x 3 x 2 factorial arrangement. A total of 2,448 male Hubbard broiler chicks were fed on practical mash diets having 2,750 kcal of ME.kg(-1) and 19.6% CP from 1 to 42 d of age. The BW gain was significantly reduced when 30% CM was added in the diets during 1 to 21 d. Feed:gain and mortality were also observed to be high. No significant effect of enzyme addition or Lys level was observed on feed intake, BW gain, feed:gain, and mortality during the starter phase. When the data were pooled for 42 d, BW gain and feed:gain were unaffected by enzyme addition or Lys levels. A depression in breast weight was observed due to 30% CM or 0.8 and 0.9% digestible Lys at 43 d. Leg weights were significantly depressed by enzyme addition or increasing digestible Lys to 1.0% of the diets. The AME, nitrogen digestibility, and antibody titers against Newcastle and infectious bursal diseases were also unaffected by the dietary treatments. In conclusion, the 30% CM is not recommended in broiler diets especially during starter phase (1 to 21 d). However, the CM may be used up to 30% of the diets during finishing phase. The digestible Lys can be lowered to 0.8% when amino acids in proportion to digestible Lys follow the ideal AA ratio. The glucanase and xylanase cocktail have no pronounced effect on the growth performance, nutrient digestibility, and carcass characteristics.