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OBJECTIVES: To identify and analyze the factors leading to extubation failure among very low birth weight infants in a specific tertiary care setting in Al Ain, emphasizing clinical and demographic variables. The study used medical data of Very Low Birth Weight (VLBW) infants admitted to the Neonatal Intensive Care Unit (NICU) from 1st January 2015 to 31st December 2019, and evaluated the incidence and risk factors associated with extubation failure. METHODS: Data was collected from the hospital's electronic records and tabulated in Excel sheets, with extubation failure defined as reintubation due to deterioration of respiratory condition within seven days post-extubation. The data was collected from the period of 1st January 2015 to 31st December 2019. Inclusion criteria included babies admitted to the NICU with a gestational age of ≤ 32 weeks, or of birth weight ≤1500 grams who were intubated within the first seven days of life. Results were analyzed using SPSS software, version 9.0 (SPSS Inc., Chicago) to determine the risk factors for extubation failure and short-term outcomes. RESULTS: Gestational age, birth weight, antenatal steroids, mode of delivery, number of Survanta® (beractant intratracheal suspension) doses, Positive End-Expiratory Pressure (PEEP), Mean Airway Pressure (MAP), Mean Arterial Pressure (Blood Pressure (BP)), and Infectious Diseases (ID) (indicated by a positive blood culture) were found to be the key predictors of extubation failure in very low birth weight infants at a tertiary care hospital in Al Ain. The most common reasons for reintubation were FiO2 > 50% (23.53%), followed by Respiratory Acidosis (20.59%). Other factors, including maternal chorioamnionitis, Apgar scores, indication for intubation, caffeine, and pre-and post-extubation laboratory values, comorbidities, and hemoglobin (Hgb), creatinine and sodium levels were found to have no effect on the success of extubations. CONCLUSIONS: The results of this research indicate that factors such as gestational age, birth weight, prenatal steroid use, delivery method, the quantity of Survanta® doses, PEEP, MAP, MAP (BP), and ID (+ve blood culture) were the primary determinants of unsuccessful extubation in VLBW babies at a tertiary healthcare facility in Al Ain. The predominant cause for needing reintubation was a FiO2 level above 50%, followed by Respiratory Acidosis. Additional ®®investigations are required to validate these findings and pinpoint other potential predictors of extubation failure within this demographic.
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Single-chain surfactants usually emulsify and stabilize oily substances into droplets in an aqueous solution. Here, we report a coassembly system, in which single types of anionic or non-ionic surfactants emulsify a class of water-soluble nonamphiphilic organic salts with fused aromatic rings in aqueous solutions. The nonamphiphilic organic salts are in turn promoted to form droplets of water-based liquid crystals (chromonic liquid crystals) encapsulated by single-chain surfactants. The droplets, stabilized against coalescence by encapsulated in a layer (or layers) of single chain surfactants, are of both nonspherical tactoid (elongated ellipsoid with pointy ends) and spherical shapes. The tactoids have an average long axis of â¼9 µm and a short axis of â¼3.5 µm with the liquid crystal aligning parallel to the droplet surface. The spherical droplets are 5-10 µm in diameter and have the liquid crystal aligning perpendicular to the droplet surface and a point defect in the center. Cationic and zwitterionic surfactants studied in this work did not promote the organic salt to form droplets. These results illustrate the complex interplay of self-association and thermodynamic incompatibility of molecules in water, which can cause new assembly behavior, including potential formation of vesicles or other assemblies, from surfactants that usually form only micelles. These unprecedented tactoidal shaped droplets also provide potential for the fabrication of new soft organic microcapsules.
Assuntos
Cristais Líquidos/química , Tensoativos/química , Emulsões/química , Estrutura Molecular , Tamanho da Partícula , Solubilidade , Soluções , Propriedades de Superfície , Água/químicaRESUMO
OBJECTIVES: Vancomycin is a glycopeptide antibiotic commonly used in neonatal intensive care units (NICUs) to treat late onset sepsis. It is recommended that vancomycin trough levels at steady state following intermittent dosing regimen be maintained at 10-20 mg/L, which is largely dependent on the type of infection. Our objective is to assess the ability of initial vancomycin dosing regimens to obtain target trough levels and to assess the percentage and risk factors associated with the development of acute kidney injury (AKI) while on vancomycin. METHODS: This is a retrospective review of all NICU patients admitted between January 2016 and December 2017 who received vancomycin according to the NeoFax at either 10 mg/kg/dose (low-dose group, LDG) or 15 mg/kg/dose (high-dose group, HDG), with a frequency based on the postmenstrual age (PMA) and postnatal age (PNA). Both regimens were compared by their ability to attain target trough levels and the episodes of vancomycin-induced AKI. Other outcomes included identification of risk factors associated with the development of vancomycin-induced nephrotoxicity. RESULTS: Of 182 patients evaluated, 44 (24%) were in the LDG and 138 patients (76%) were in the HDG. Ninety-one patients (50%) attained target trough levels of 10-20 mg/L. Among these and according to patients' PMA, 48% in the HDG versus 7% in the LDG in PMA ≤29 weeks and 69% in the HDG versus 18% in the LDG in PMA 30-36 weeks attained target trough levels (p=0.006 and p<0.001, respectively). According to PNA, 47% in the HDG versus none in the LDG in patients <7 days old and 61% in the HDG versus 10% in the LDG in patients aged 8-14 days attained target trough levels (p=0.025 and p=0.016, respectively). A total of 14% developed AKI in the LDG vs 7% in the HDG (p=0.225). Only PMA ≤29 weeks (OR, 4.5, 95% CI 1.5 to 13), vancomycin trough levels >20 mg/L (OR 5.1, 95% CI 1.5 to 17), hypotension (OR 11.02, 95% CI 3.5 to 34) and furosemide (OR 4.4, 95% CI 1.4 to 13.5) were significantly associated with vancomycin-induced AKI in our NICU. CONCLUSION: Vancomycin dosing in neonates according to the NeoFax did not provide sufficient attainment of target trough levels (10-20 mg/L). However, using the higher dosing range at 15 mg/kg/dose was more likely to reach target levels, with no measured increased risk of nephrotoxicity. Extreme premature neonates, supratherapeutic vancomycin trough levels, hypotension and furosemide use are associated with an increased incidence of vancomycin-induced nephrotoxicity.
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Sepse , Vancomicina , Adolescente , Antibacterianos , Criança , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Fatores de Risco , Sepse/tratamento farmacológico , Vancomicina/efeitos adversosRESUMO
Recent studies have demonstrated melatonin protects various crops against abiotic stresses. However, the effects of melatonin on the photosynthetic apparatus of stressed plants is poorly characterized. We investigated the effects of melatonin pretreatment on photosynthesis and tolerance to salinity stress in Avena sativa (oat) plants. Oat plants were exposed to four treatments (three replicate pots per treatment): well-watered (WW; control); watered with 300 mM salt solution for 10 days (NaCl); pretreated with 100 µM melatonin solution for 7 days then watered normally for 10 days (Mel+W); or pretreated with 100 µM melatonin for 7 days then 300 mM salt for 10 days (Mel+NaCl). Considerable differences in growth parameters, chlorophyll content, stomatal conductance, proline accumulation, lipid peroxidation, electrolyte leakage, and growth parameters were observed between groups. Genes encoding three major antioxidant enzymes were upregulated in the Mel+NaCl group compared to the other groups. Chlorophyll-a fluorescence kinetic analyses revealed that almost all photosynthetic parameters were improved in Mel+NaCl plants compared to the other treatments. Analysis of genes encoding the major extrinsic proteins of photosystem II (PSII) revealed that PsbA, PsbB, PsbC, and PsbD (but not PsbO) were highly upregulated in Mel+NaCl plants compared to the other groups, indicating melatonin positively influenced photosynthesis under control conditions and salt stress. In addition, melatonin upregulated stress-responsive NAC transcription factor genes in plants exposed to salt stress. These findings suggest melatonin pretreatment improves photosynthesis and enhances salt tolerance in oat plants.
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AIM: To evaluate the prevalence, risk factors and outcome of acute kidney injury (AKI) in very low birth weight (VLBW) infants. METHODS: In this retrospective study of VLBW infants, we analyzed the prevalence of AKI, as defined by changes in serum creatinine and urine output, associated risk factors and outcomes. RESULTS: A total of 293 VLBW infants (mean gestational age 28.7 wk) were included, of whom 109 weighed less than 1000 g at birth. The overall prevalence of AKI was 11.6% (22% in infants with a birth weight under 1000 g and 5.4% those heavier). A total of 19 (55%) affected infants died, with a mortality rate of 58% in infant less than 1000 g and 50% in those heavier. After adjusting for confounding variables, only necrotizing enterocolitis (NEC) remained associated with AKI, with odds ratio of 4.9 (95%CI: 1.9-18.6). Blood pressure and glomerular filtration rate (GFR) were not different between affected infants and the others upon discharge from hospital. A normal GFR was documented in all affected infants at one year of age. CONCLUSION: Using Kidney Disease Improving Global Outcomes definition of AKI, it occurred in over 10% of VLBW infants, more commonly in infants with lower birth weight. NEC was an independent associated risk factor. Renal function, as defined by GFR, was normal in all surviving affected infants 10 to 12 mo later.
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When attacked, many decapod crustaceans perform tailflips, which are triggered by a neural circuit that includes lateral giant interneurons, medial giant interneurons, and fast flexor motor giant neurons (MoGs). Slipper lobsters (Scyllaridae) lack these giant neurons, and it has been hypothesized that behavioral (e.g., digging) and morphological (e.g., flattening and armor) specializations in this group caused the loss of escape-related giant neurons. To test this hypothesis, we examined a species of spiny lobster, Panulirus argus. Spiny lobsters belong to the sister taxon of the scyllarids, but they have a more crayfish-like morphology than scyllarids and were predicted to have escape-related giant neurons. Ventral nerve cords of P. argus were examined using paraffin-embedded sections and cobalt backfills. We found no escape-related giant neurons and no large axon profiles in the dorsal region of the nerve cord of P. argus. Cobalt backfills showed one fewer fast flexor motor neuron than in species with MoGs and none of the fast flexor motor neurons show any of the anatomical specializations of MoGs. This suggests that all palinuran species lack this giant escape circuit, and that the loss of rapid escape behavior preceded, and may have driven, alternative predator avoidance and anti-predator strategies in palinurans.
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Gânglios dos Invertebrados/fisiologia , Neurônios/fisiologia , Palinuridae/anatomia & histologia , Palinuridae/fisiologia , Animais , Astacoidea/anatomia & histologia , Astacoidea/fisiologia , Axônios/fisiologia , Reação de Fuga/fisiologia , Gânglios dos Invertebrados/anatomia & histologia , Comportamento PredatórioRESUMO
Adhesion on a surface via nonspecific attachment or multiple ligand-receptor interactions is a critical event for fungal infection by Candida albicans. Here, we find that the tri(ethylene glycol)- and d-mannitol-terminated monolayers do not resist the blastospore attachment, but prevent the hyphae adhesion of C. albicans. The hyphae adhesion can be facilitated by tripeptide sequences of arginine-glycine-aspartic acid (RGD) covalently decorated on a background of tri(ethylene glycol)-terminated monolayers. This adhesion mediated by selected ligands is sensitive to the scrambling of peptide sequences, and is inhibited by the presence of cyclic RGD peptides in the solution.
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Candida albicans/química , Hifas/química , Esporos Fúngicos/química , Adesividade , Ligantes , Manitol/química , Peptídeos Cíclicos/química , Polietilenoglicóis/químicaRESUMO
The physical properties of many organic molecules often oscillate when the number of carbons in their aliphatic chains changes from odd to even. This odd-even effect for single-chain surfactants in solution is rarely observed. Here, we report the ability of single-chain surfactants to emulsify a class of non-amphiphilic organic salts, disodium cromoglycate (5'DSCG) oscillates as a function of the odd or even number of the aliphatic carbons. This system provides a water-in-oil-in-water emulsion, in which aqueous droplets of 5'DSCG in liquid crystal phases are coated with single-chain surfactants in a bulk carrying aqueous solution. For both surfactants of [Formula: see text] and CH3(CH2)nCOO(-)Na(+), the ability to emulsify 5'DSCG molecules in water is stronger for surfactants with an odd number of sp(3)-hybridized carbon atoms in the aliphatic chains than those with an even number. This observed odd-even effect is consistent with the notion that conventional micelles possess a core of randomly arranged surfactant hydrocarbon tails. However, this water-in-oil-in-water resembles a vesicle system in which the surfactants assemble in a highly ordered structure that separates two aqueous systems. These new self-assembled phases have potential application in the formulation and design of new organic soft materials.
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Emulsões , Tensoativos/química , Cristalização , Água/químicaRESUMO
INTRODUCTION: It has been always an area of diffuse clarity when you study malignancy and its pathogenesis. Recently, it has invited lot of interest among the researchers about the possibility of role of viruses in the initiation of carcinogenesis. Recent advances in the field of molecular biology and biotechnology have solved some problems with regard to pathogenesis. Human papilloma virus (HPV) and its role in the initiation of malignancy in the cervix is proven almost beyond doubt. OBJECTIVES: The present study is aimed at the role of two types of HPV 16 and 18 in the initiation of oral premalignant and squamous cell carcinoma. The study also aims at using polymerase chain reaction (PCR) in finding out the prevalence of these types diagnosed histologically as oral leukoplakia and oral squamous cell carcinoma and prevalence of its association with the habit of tobacco use. MATERIALS AND METHODS: In the present study, 45 patients having histopathologically confirmed oral squamous cell carcinoma in the age range of 32-85 years were selected along with 20 histopathologically confirmed oral leukoplakia in the age range 22-66 years. All the samples were subjected to polymerase chain reaction. The PCR reaction was carried out in PTC 200 thermo-cycler [MJ Research Inc, Watertown, MA, USA]. RESULTS: The site prevalence and co-infection rate of these two types of viruses are being analyzed using very simple non-invasive scrapings obtained from fresh scrapings and found to be really high. It was also observed that 73.3% (33/45) of the oral squamous cell carcinoma patients were positive for oral HPV type 16 while 71.1% (32/45) were positive for HPV type 18 infection and 57.7% (26/45) were found to have both HPV type 16 and HPV type 18 infections. CONCLUSIONS: HPV type 16, 18, and co-infection of both types showed high prevalence in oral squamous cell carcinoma.The prevalence of HPV type 18 was found to be higher than HPV type 16 and co-infection in oral leukoplakia. It was observed that the tongue and palate lesions in the oral squamous cell carcinoma patients showed high prevalence of HPV type 16, type 18, and co-infection compared with other sites.
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Carcinoma de Células Escamosas/epidemiologia , DNA Viral/análise , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Leucoplasia Oral/epidemiologia , Neoplasias Bucais/epidemiologia , Infecções por Papillomavirus/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/métodos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/virologia , Feminino , Humanos , Leucoplasia Oral/diagnóstico , Leucoplasia Oral/virologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/virologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase/métodos , Prevalência , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , Emirados Árabes Unidos/epidemiologia , Adulto JovemRESUMO
This work studies the phase separations between polymers and a small molecule in a common aqueous solution that do not have well-defined hydrophobic-hydrophilic separation. In addition to poly(acrylamide) (PAAm) and poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP) also promotes liquid crystal (LC) droplet formation by disodium cromoglycate (5'DSCG) solvated in water. In the presence of these polymers, the concentration of 5'DSCG needed for forming LC droplets is substantially lower than that needed for forming an LC phase by 5'DSCG alone. To define the concentration ranges that 5'DSCG molecules form liquid crystals (either as droplets or as an isotropic-LC mixture), we constructed ternary phase diagrams for 5'DSCG, water, and a polymer - PVA, PVP, or PAAm. We discovered that PAAm with high molecular weight promotes LC droplet formation by 5'DSCG more effectively than PAAm with low molecular weight. At the same weight percentage, long-chain PAAm can cause 5'DSCG to form LC droplets in water, whereas short-chain PAAm does not. Poly(vinyl pyrrolidone) (PVP), which has functional groups that are more dissimilar to 5'DSCG than PVA and PAAm, promotes LC droplet formation by 5'DSCG more effectively than either of the other two polymers. Additionally, small angle neutron scattering data revealed that the assembly structure of 5'DSCG promoted by the presence of PVA is similar to the thread structure formed by 5'DSCG alone. Together, these results reveal how noncovalent polymerization can be promoted by mixing thermodynamically incompatible molecules and elucidate the basic knowledge of nonamphiphilic colloidal science.
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Polímeros/química , Água/química , Cromolina Sódica/química , Cristalização , Interações Hidrofóbicas e Hidrofílicas , Cristais Líquidos/química , Estrutura Molecular , Espalhamento a Baixo Ângulo , Soluções , TermodinâmicaRESUMO
Introduction: It has been always an area of diffuse clarity when you study malignancy and its pathogenesis. Recently, it has invited lot of interest among the researchers about the possibility of role of viruses in the initiation of carcinogenesis. Recent advances in the field of molecular biology and biotechnology have solved some problems with regard to pathogenesis. Human papilloma virus (HPV) and its role in the initiation of malignancy in the cervix is proven almost beyond doubt. Objectives: The present study is aimed at the role of two types of HPV 16 and 18 in the initiation of oral premalignant and squamous cell carcinoma. The study also aims at using polymerase chain reaction (PCR) in finding out the prevalence of these types diagnosed histologically as oral leukoplakia and oral squamous cell carcinoma and prevalence of its association with the habit of tobacco use. Materials and Methods:In the present study, 45 patients having histopathologically confirmed oral squamous cell carcinoma in the age range of 32-85 years were selected along with 20 histopathologically confirmed oral leukoplakia in the age range 22-66 years. All the samples were subjected to polymerase chain reaction. The PCR reaction was carried out in PTC 200 thermo-cycler [MJ Research Inc, Watertown, MA, USA]. Results: The site prevalence and co-infection rate of these two types of viruses are being analyzed using very simple non-invasive scrapings obtained from fresh scrapings and found to be really high. It was also observed that 73.3% (33/45) of the oral squamous cell carcinoma patients were positive for oral HPV type 16 while 71.1% (32/45) were positive for HPV type 18 infection and 57.7% (26/45) were found to have both HPV type 16 and HPV type 18 infections. Conclusions:HPV type 16, 18, and co-infection of both types showed high prevalence in oral squamous cell carcinoma.The prevalence of HPV type 18 was found to be higher than HPV type 16 and co-infection in oral leukoplakia. It was observed that the tongue and palate lesions in the oral squamous cell carcinoma patients showed high prevalence of HPV type 16, type 18, and co-infection compared with other sites.