Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 81
Filter
2.
Sci Rep ; 12(1): 10378, 2022 Jun 20.
Article in English | MEDLINE | ID: mdl-35726007

ABSTRACT

Electrohydrodynamic flow control systems have proven to be among the most promising flow control strategies within previous decades. Several methods for efficient evaluation and description of the effect of such systems are indeed available. Yet, due to these systems' critical role in various applications, possible improvements are still investigated. A new phenomenological model is presented for the simulation of the plasma actuators based on the electrodynamic properties of low-frequency plasmons. The model simulates the plasmonic region as a dispersive medium. This dissipated energy is added to the flow by introducing a high-pressure region, calculated in terms of local body force vectors, requiring the distribution of the electric field and the polarization field. The model determines the electric field for the computation of the body force vector based on the Poisson equation and implements the simplified Lorentz model for the polarization field. To fully explore the performance of the presented model, an experiment has been conducted providing a comparison between the observed effect of plasma actuators on the fluid flow with the results predicted by the model. The model is then validated based on the results of other distinct experiments and exempted numerical models, based on the exchanging momentum with the ambient neutrally charged fluid, demonstrating that the model has improved adaptability and self-adjusting capability compared to the available models.

3.
CBE Life Sci Educ ; 20(4): ar64, 2021 12.
Article in English | MEDLINE | ID: mdl-34714688

ABSTRACT

The Science Teaching Experience Program-Working in Science Education (STEP-WISE) provides teaching experience for postdoctoral scholars holding full-time research appointments. Through a combination of mentorship, deliberate practice, and feedback, the postdocs learn and apply inclusive, evidence-based pedagogies. STEP-WISE is integrated into postdocs' demanding schedules and is sustainable for institutions to run. Here, we assess the effectiveness of STEP-WISE. We used the Classroom Observation Protocol for Undergraduate STEM instruction to quantify instructor and student behaviors in 20 STEP-WISE class sessions from seven courses designed and taught by postdocs in the program. We found that all of the postdocs used student-centered teaching strategies. Also, using a design-based research framework, we studied the program to identify the salient components of its design. Four interconnected key elements contribute to the program's success: 1) two training sessions, 2) a precourse meeting with the mentor, 3) implementation of active-learning strategies with support, and 4) debriefing with the mentor after each class session. STEP-WISE is a replicable model to support postdocs seeking training and experience in evidence-based teaching practices geared to improving undergraduate education and transforming pedagogical practice. We conclude that high-impact teaching can be learned early in a career with streamlined training and intensive mentoring.


Subject(s)
Mentoring , Mentors , Humans , Learning , Research Personnel , Students
4.
Mol Immunol ; 103: 322-335, 2018 11.
Article in English | MEDLINE | ID: mdl-30366166

ABSTRACT

Impaired wound healing is a serious complication of diabetes that negatively affects the patient's socioeconomic life. Multiple mechanisms contribute to impaired diabetic wound healing including deficient recruitment of wound macrophages/neutrophils and impaired neovascularization. Bee venom (BV) has been used as an anti-inflammatory agent for the treatment of several diseases. Nevertheless, the impacts of BV on the diabetic wound healing have been poorly studied. In the present study, we investigated the molecular mechanisms underlying BV treatment on diabetic wound healing in a type I diabetic mouse model. Three experimental groups were used: group 1, non-diabetic control mice; group 2, vehicle-diabetic mice; and group 3, BV-treated diabetic mice. We found that the diabetic mice exhibited impaired wound closure characterized by a significant decrease in collagen and ß-defensin-2 (BD-2) expression compared to control non-diabetic mice. The impairment of diabetic wound healing is attributed to increased ROS levels and abolished antioxidant enzymes activity in the wounded tissues. Additionally, wounded tissue in diabetic mice revealed aberrantly decreased levels of Ang-1 and Nrf2 (the agonist ligands of Tie-2) followed by a marked reduction in the phosphorylation of Tie2 and downstream signaling eNOS, AKT and ERK. Impaired diabetic wound healing was also characterized by a significant reduction in activities of total antioxidant enzymes followed by a marked reduction in the levels of CCL2, CCL3 and CXCL2; which led to impaired recruitment and functions of wound macrophages/neutrophils; and significant reduction in the expression of CD31, a marker for neovascularization and angiogenesis of the injured tissue. Interestingly, BV treatment significantly enhanced wound closure in diabetic mice by increasing collagen and BD-2 expression and restoring the levels of Ang-1 and Nrf2 and hence enhancing the Tie-2 downstream signaling. Most importantly, treatment of diabetic mice with BV significantly restored the activities of wounded tissue antioxidant enzymes and the levels of chemokines, and subsequently rescued wound macrophages from mitochondrial membrane potential-induced apoptosis. Our findings reveal the immune-enhancing effects of BV for improving healing process of diabetic wounds and provide the first insight concerning the underlying molecular mechanisms.


Subject(s)
Apoptosis/drug effects , Bee Venoms/pharmacology , Diabetes Mellitus, Experimental/physiopathology , Macrophages/drug effects , Proteins/metabolism , Wound Healing/drug effects , Angiopoietin-1/metabolism , Animals , Cells, Cultured , Collagen/metabolism , Disease Models, Animal , Humans , Macrophages/metabolism , Male , Mice, Inbred BALB C , NF-E2-Related Factor 2/metabolism , Protective Agents/pharmacology , Receptor, TIE-2/metabolism , Signal Transduction/drug effects , Wound Healing/physiology , beta-Defensins/metabolism
5.
J Food Sci Technol ; 54(13): 4205-4212, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29184226

ABSTRACT

Aluminum toxicity might be related to oxidative stress, and the antioxidant activity and protective effect of bee bread, which contains pollen, honey and bees' enzymes, on aluminum induced blood and hepato-renal toxicity was investigated in rats. Chemical analysis and antioxidant capacity of bee bread were conducted. The animal experiment in rats included; group 1: received distilled water (10 ml/kg b.wt), group 2: received aluminum chloride (662.2 mg/kg b.wt), group 3: received aluminum chloride (662.2 mg/kg b.wt) and ethanolic extract of the bee bread (500 mg/kg b.wt), and group 4: received aluminum chloride (662.2 mg/kg b.wt) and ethanolic extract of the bee bread (750 mg/kg b.wt). Doses were given once daily via a gavage. C-reactive protein, transaminases, urea, creatinine, creatinine clearance, sodium and potassium and urine sodium and potassium were determined on day 28 of the experiment. Bee bread contained protein, fat, fiber, ash, carbohydrate, phenol and flavonoids and it exhibited antioxidant activity. Aluminum caused a significant elevation of blood urea, transaminase, C-reactive protein and monocyte count and significantly decreased hemoglobin. These changes were significantly ameliorated by the use of bee bread. Bee bread has an antioxidant property, and exhibited a protective effect on aluminum induced blood and hepato-renal toxicity and elevation of inflammatory markers C-reactive protein, leukocyte and monocyte counts.

6.
J Perinatol ; 36(11): 972-976, 2016 11.
Article in English | MEDLINE | ID: mdl-27513327

ABSTRACT

OBJECTIVE: The current state of point-of-care ultrasonography (POCUS) use and education in neonatal-perinatal medicine (NPM) and pediatric critical care medicine (PCCM) is unknown. Our aim was to quantify POCUS use, training and perceptions regarding education and barriers among the United States NPM and PCCM fellowship programs. STUDY DESIGN: A 14-question survey was emailed to the fellowship directors of all the United States NPM and PCCM fellowship programs. RESULTS: The response rate was 55% (52/95) and 59% (39/66) for NPM and PCCM programs, respectively. Over 90% of respondents in both groups believe that fellows and attendings should receive POCUS training. PCCM programs, compared with NPM, had greater access to POCUS machines (97% vs 63%, P<0.001), and more often used POCUS for diagnoses and management (76% vs 29%, P<0.001) and procedural guidance (95% vs 37%, P<0.001). The most common indications were cardiac/hemodynamics, pulmonary pathology and vascular access in both specialties. PCCM reported more training to fellows (90% vs 29%, P<0.001). Both group perceived lack of time to learn, lack of equipment/funds, liability concerns, lack of personnel to train physicians and cardiology/radiology resistance as significant barriers to POCUS implementation. CONCLUSIONS: Both NPM and PCCM fellowship programs believe in the benefits of POCUS and that their physicians should receive the necessary training. Compared with PCCM, NPM fellowships programs have less access to POCUS machines and less frequently use POCUS and train their fellows and attendings. There remain significant barriers to utilization of POCUS, especially in NPM.


Subject(s)
Critical Care/methods , Pediatrics/education , Point-of-Care Systems/statistics & numerical data , Ultrasonography/statistics & numerical data , Attitude of Health Personnel , Child , Cross-Sectional Studies , Curriculum , Fellowships and Scholarships/statistics & numerical data , Humans , Internship and Residency/statistics & numerical data , Surveys and Questionnaires , United States
7.
Cell Physiol Biochem ; 39(1): 115-22, 2016.
Article in English | MEDLINE | ID: mdl-27322825

ABSTRACT

BACKGROUND/AIMS: Natural honey has many biological activities including protective effect against toxic materials. The aim of this study was to evaluate the protective effect of carob honey against lead-induced hepato-renal toxicity and lead-induced anemia in rabbits. METHODS: Twenty four male rabbits were allocated into four groups six rabbits each; group 1: control group, received distilled water (0.1 ml / kg.b.wt /daily); group 2: received oral lead acetate (2 g/kg.b.wt/daily); group 3: treated with oral honey (1g /kg.b.wt/daily) and oral lead (2 g/kg.b.wt/daily), and group 4: received oral honey (1 g/kg.b.wt/daily). Honey and lead were given daily during 24 days of experimentation. Laboratory tests and histopathological evaluations of kidneys were done. RESULTS: Oral administration of lead induced hepatic and kidney injury and caused anemia during three weeks of the exposure. Treatment with honey prevented hepato-renal lead toxicity and ameliorated lead-induced anemia when honey was given to animals during lead exposure. CONCLUSION: It might be concluded that honey has a protective effect against lead-induced blood, hepatic and renal toxic effects.


Subject(s)
Anemia/prevention & control , Honey , Kidney/drug effects , Lead/toxicity , Liver/drug effects , Protective Agents/pharmacology , Administration, Oral , Anemia/chemically induced , Animals , Body Weight/drug effects , Creatinine/blood , Hemoglobins/metabolism , Kidney/pathology , Kidney/physiopathology , Lead/administration & dosage , Leukocyte Count , Liver/pathology , Liver/physiopathology , Male , Morocco , Protective Agents/administration & dosage , Rabbits , Time Factors
8.
J Perinatol ; 36(9): 784-6, 2016 09.
Article in English | MEDLINE | ID: mdl-27078203

ABSTRACT

OBJECTIVE: Point-of-care ultrasonography (POCUS) is becoming increasingly available for neonatologists and pediatric subspecialists (PSS); however, concerns over potential litigation from possible missed diagnoses or incorrect management have been documented. This study aims to define the extent and quality of lawsuits filed against neonatologists and PSS related to POCUS. STUDY DESIGN: We conducted a retrospective study of all United States reported state and federal cases in the Westlaw database from January 1990 through October 2015. Cases were reviewed and included if either a neonatologist or PSS were accused of misconduct or the interpretation or failure to perform an ultrasound/echocardiogram was discussed. Descriptive statistics were used to evaluate the data. RESULTS: Our search criteria returned 468 results; 2 cases were determined to be relevant to the study objective. The two cases alleged a failure to perform a diagnostic test and implicated POCUS as an option. There were no cases of neonatologists and PSS being sued for POCUS performance or interpretation. CONCLUSION: This study of a major legal database suggests that POCUS use and interpretation is not a significant cause of lawsuits against neonatologists and PSS.


Subject(s)
Malpractice/legislation & jurisprudence , Neonatologists/legislation & jurisprudence , Point-of-Care Systems/statistics & numerical data , Ultrasonography/statistics & numerical data , Humans , Infant, Newborn , Malpractice/statistics & numerical data , Neonatology , Point-of-Care Systems/legislation & jurisprudence , Retrospective Studies , United States
9.
Vet Comp Oncol ; 14(2): 137-46, 2016 Jun.
Article in English | MEDLINE | ID: mdl-24447820

ABSTRACT

Mouse Double Minute-2 (MDM2) is an ubiquitin ligase which is overexpressed or its promoter polymorphism has been reported in different tumours. The objective of this study was to examine the MDM2 protein expression and its promoter polymorphism in some canine tumours. Twenty specimens were collected from 20 dogs with 15 mammary gland carcinomas, 3 lymphomas, 1 transmissible venereal tumour and 1 trichoblastoma. Samples were analysed immunohistochemically using human antibody against MDM2 protein. PCR and DNA sequencing were carried out to identify MDM2 promoter polymorphism. MDM2 gene was expressed in 13 of 20 samples including 11 mammary carcinomas, 1 lymphoma and 1 trichoblastoma. We found 94% homology between canine and human sequences. Four mutations including G169C, A177G, G291T and A177G were identified in different types of breast carcinomas. An extra p53 response element was found in a mixed mammary carcinoma.


Subject(s)
Dog Diseases/metabolism , Gene Expression Regulation, Neoplastic/physiology , Polymorphism, Genetic , Promoter Regions, Genetic/genetics , Proto-Oncogene Proteins c-mdm2/metabolism , Animals , Carcinoma/genetics , Carcinoma/metabolism , Carcinoma/veterinary , Dog Diseases/genetics , Dogs , Lymphoma/genetics , Lymphoma/metabolism , Lymphoma/veterinary , Proto-Oncogene Proteins c-mdm2/genetics , Venereal Tumors, Veterinary/genetics , Venereal Tumors, Veterinary/metabolism
10.
Cell Physiol Biochem ; 37(3): 940-54, 2015.
Article in English | MEDLINE | ID: mdl-26381245

ABSTRACT

BACKGROUND/AIMS: Impaired wound healing is considered to be one of the most serious complications associated with diabetes as it significantly increases the susceptibility of patients to infection. Propolis is a natural bee product used extensively in foods and beverages that has significant benefits to human health. In particular, propolis has antioxidant, anti-inflammatory and analgesic effects that could be useful for improving wound healing. In this study, we investigated the effects of topical application of propolis on the healing and closure of diabetic wounds in a streptozotocin (STZ)-induced type I diabetic mouse model. METHODS: Sixty male mice were distributed equally into 3 experimental groups: group 1, non-diabetic control mice; group 2, diabetic mice; and group 3, diabetic mice treated daily with a topical application of propolis. RESULTS: We found that diabetic mice exhibited delayed wound closure characterized by a significant decrease in the levels of TGF-ß1 and a prolonged elevation of the levels of inflammatory cytokines (IL-1ß, IL-6 and TNF-α) and MMP9 in wound tissues compared with control non-diabetic mice. Moreover, the wound tissues of diabetic mice showed a marked reduction in the phosphorylation of Smad2 and Smad3 as well as a marked reduction in collagen production. Interestingly, compared with untreated diabetic mice, topical application of propolis significantly enhanced the closure of diabetic wounds and decreased the levels of IL-1ß, IL-6, TNF-α and MMP9 to near normal levels. Most importantly, compared with untreated diabetic mice, the treatment of diabetic mice with propolis significantly enhanced the production of collagen via the TGF-ß1/Smad2,3 signaling axis in wounded tissues. CONCLUSION: Our findings reveal the molecular mechanisms underlying the improved healing and closure of diabetic wounds following topical propolis application.


Subject(s)
Collagen/metabolism , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 1/metabolism , Propolis/administration & dosage , Smad Proteins/metabolism , Transforming Growth Factor beta/metabolism , Wound Healing/drug effects , Administration, Topical , Animals , Cytokines/metabolism , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Type 1/chemically induced , Drug Administration Schedule , Gene Expression Regulation/drug effects , Humans , Male , Matrix Metalloproteinase 9/metabolism , Mice , Propolis/pharmacology , Streptozocin
11.
BMC Immunol ; 16: 54, 2015 Sep 15.
Article in English | MEDLINE | ID: mdl-26370805

ABSTRACT

BACKGROUND: Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease caused by the selective destruction of pancreatic ß cells, followed by hyperglycemia, oxidative stress and the subsequent extensive impairment of immune cell functions, a phenomenon responsible for the development of chronic diabetic complications. Propolis, a natural bee product that is extensively used in foods and beverages, significantly benefits human health. Specifically, propolis exerts antioxidant, anti-inflammatory and analgesic effects that may improve diabetic complications. To further elucidate the potential benefits of propolis, the present study investigated the effect of dietary supplementation with propolis on the plasma cytokine profiles, free radical levels, lipid profile and lymphocyte proliferation and chemotaxis in a streptozotocin (STZ)-induced type I diabetic mouse model. METHODS: Thirty male mice were equally distributed into 3 experimental groups: group 1, non-diabetic control mice; group 2, diabetic mice; and group 3, diabetic mice supplemented daily with an ethanol-soluble derivative of propolis (100 mg/kg body weight) for 1 month. RESULTS: First, the induction of diabetes in mice was associated with hyperglycemia and significant decreases in the insulin level and the lymphocyte count. In this context, diabetic mice exhibited severe diabetic complications, as demonstrated by a significant decrease in the levels of IL-2, IL-4 and IL-7, prolonged elevation of the levels of pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α) and reactive oxygen species (ROS) and altered lipid profiles compared with control non-diabetic mice. Moreover, antigen stimulation of B and T lymphocytes markedly reduced the proliferative capacity and chemotaxis of these cells towards CCL21 and CXCL12 in diabetic mice compared with control mice. Interestingly, compared with diabetes induction alone, treatment of diabetic mice with propolis significantly restored the plasma cytokine and ROS levels and the lipid profile to nearly normal levels. Most importantly, compared with untreated diabetic mice, diabetic mice treated with propolis exhibited significantly enhanced lymphocyte proliferation and chemotaxis towards CCL21 and CXCL12. CONCLUSION: Our findings reveal the potential immuno-modulatory effects of propolis, which acts as a natural antioxidant to enhance the function of immune cells during diabetes.


Subject(s)
B-Lymphocytes/cytology , Chemokines/pharmacology , Chemotaxis/drug effects , Cytokines/blood , Diabetes Mellitus, Experimental/drug therapy , Lipids/blood , Propolis/therapeutic use , T-Lymphocytes/cytology , Administration, Oral , Animals , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , Blood Glucose/metabolism , Cell Proliferation/drug effects , Chemokine CCL21/pharmacology , Chemokine CXCL12/pharmacology , Diabetes Complications/blood , Diabetes Complications/drug therapy , Diabetes Complications/pathology , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/pathology , Dietary Supplements , Disease Models, Animal , Free Radicals/metabolism , Inflammation Mediators/metabolism , Insulin/blood , Male , Mice, Inbred BALB C , Obesity/blood , Obesity/drug therapy , Oxidative Stress/drug effects , Propolis/administration & dosage , Propolis/pharmacology , T-Lymphocytes/drug effects , T-Lymphocytes/immunology
12.
J Perinatol ; 35(6): 424-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25590219

ABSTRACT

OBJECTIVE: To evaluate the cardiovascular response to short-term prone positioning in neonates. STUDY DESIGN: In this prospective study, we continuously monitored heart rate (HR), stroke volume (SV) and cardiac output (CO) by electrical velocimetry in hemodynamically stable neonates in each of the following positions for 10 min: supine, prone and back-to-supine position. Skin blood flow (SBF) was also continuously assessed on the forehead or foot using Laser Doppler technology. Systemic vascular resistance (SVR) index was calculated as mean blood pressure (BP)/CO. Data were analyzed using repeated measures analysis of variance. RESULTS: Thirty neonates (gestational age: 35±4 weeks; postmenstrual age: 36±3 weeks) were enrolled. HR did not change in response to positioning. However, in prone position, SV, CO and SBF decreased and SVR index increased from 1.5±0.3 to 1.3±0.3 ml kg(-1) (mean ±s.d., P<0.01), 206±44 to 180±41 ml kg(-1) min(-1) (P<0.01), 0.54±0.30 to 0.44±0.29 perfusion units (P<0.01) and 0.25±0.06 to 0.30±0.07 mm Hg ml(-1) kg(-1) min(-1) (P<0.01), respectively. After placing the infants back-to-supine position, SV, CO, SBF and SVR index returned to baseline. The above pattern of cardiovascular changes was consistent in vast majority of the studied neonates. CONCLUSIONS: Short-term prone positioning is associated with decreased SV, CO and SBF and increased calculated SVR index.


Subject(s)
Cardiac Output/physiology , Infant, Newborn/physiology , Prone Position/physiology , Vascular Resistance/physiology , Female , Heart Rate/physiology , Humans , Laser-Doppler Flowmetry , Male , Prospective Studies , Skin/blood supply , Stroke Volume/physiology , Supine Position/physiology
13.
J Perinatol ; 35(2): 123-7, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25118721

ABSTRACT

OBJECTIVE: We performed a multicenter study of preterm infants, who were about to undergo patent ductus arteriosus ligation, to determine whether echocardiographic indices of impaired myocardial performance were associated with subsequent development of catecholamine-resistant hypotension following ligation. STUDY DESIGN: A standardized treatment approach for hypotension was followed at each center. Infants were considered to have catecholamine-resistant hypotension if their dopamine infusion was > 15 µg kg(-1)min(-1). Echocardiograms and cortisol measurements were obtained between 6 and 14 h after the ligation (prior to the presence of catecholamine-resistant hypotension). RESULT: Forty-five infants were enrolled, 10 received catecholamines (6 were catecholamine-responsive and 4 developed catecholamine-resistant hypotension). Catecholamine-resistant hypotension was not associated with decreased preload, shortening fraction or ventricular output. Infants with catecholamine-resistant hypotension had significantly lower levels of systemic vascular resistance and postoperative cortisol concentration. CONCLUSION: We speculate that low cortisol levels and impaired vascular tone may have a more important role than impaired cardiac performance in post-ligation catecholamine-resistant hypotension.


Subject(s)
Cardiac Surgical Procedures/adverse effects , Dopamine , Ductus Arteriosus, Patent/surgery , Hypotension , Postoperative Complications , Cardiac Surgical Procedures/methods , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/adverse effects , Catecholamines/administration & dosage , Catecholamines/adverse effects , Dobutamine/administration & dosage , Dobutamine/adverse effects , Dopamine/administration & dosage , Dopamine/adverse effects , Drug Resistance , Echocardiography , Female , Humans , Hypotension/diagnosis , Hypotension/drug therapy , Hypotension/etiology , Hypotension/physiopathology , Infant, Newborn , Infant, Premature , Ligation , Male , Postoperative Complications/diagnosis , Postoperative Complications/drug therapy , Postoperative Complications/physiopathology , Treatment Outcome
14.
J Perinatol ; 34(11): 847-9, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25033075

ABSTRACT

OBJECTIVE: To investigate the effect of targeted neonatal echocardiography (TnEcho) on heart rate, arterial oxygen saturation (SPO2), cerebral regional oxygen saturation (CrSO2) and cerebral fractional oxygen extraction (CFOE) in extremely preterm infants during the first 3 postnatal days. STUDY DESIGN: s a nested study in a prospective observational study, we acquired continuous data on heart rate, SPO2, CrSO2 and CFOE. Data averaged for the duration of TnEcho study were compared with the data collected during a baseline period immediately before the start of echocardiography. The duration of the baseline and study periods was the same. TnEcho evaluation included assessment of preload, afterload, contractility, left and right ventricular output, patent ductus arteriosus and foramen ovale. RESULT: We analyzed 138 data pairs before and during TnEcho in 22 extremely preterm infants (gestational age 25.9 ± 1.2 weeks; range 23 to 27). There was no significant difference in heart rate between baseline and TnEcho period. There was a statistical, but clinically negligible, difference between baseline and TnEcho in SPO2 (median (quartile) 91.4% (88.9, 94.2) vs 91.3% (88.9, 94), P = 0.048), CrSO2 (76.8% (70.7, 81.5) vs 74.9% (69.5, 80.1), P<0.0001) and CFOE (15.8% (9.8, 23.6) vs 17.5% (11.3, 24.7), P<0.0001). The changes in the parameters monitored were similar in preterm infants who developed peri/intraventricular hemorrhage and in those who did not. CONCLUSION: Although there were statistically significant changes in SPO2, CrSO2 and CFOE, the alterations were minimal and unlikely of clinical relevance. Thus, cerebral hemodynamics and systemic and cerebral oxygenation are not perturbed during TnEcho and the procedure is well tolerated by the extremely preterm infants during the postnatal transitional period.


Subject(s)
Brain/blood supply , Echocardiography/methods , Infant, Extremely Premature/physiology , Infant, Premature, Diseases/diagnostic imaging , Infant, Premature, Diseases/physiopathology , Ductus Arteriosus, Patent/diagnostic imaging , Heart Rate/physiology , Humans , Infant, Newborn , Intracranial Hemorrhages/diagnostic imaging , Intracranial Hemorrhages/physiopathology , Oxygen/blood , Prospective Studies , Regional Blood Flow
15.
Arch Med Sci ; 10(2): 246-50, 2014 May 12.
Article in English | MEDLINE | ID: mdl-24904656

ABSTRACT

INTRODUCTION: Honey has a wide range of antimicrobial activity. All previous studies have considered honey's effect on a single microbe. The present study investigated activity of honey towards a high dose of single or polymicrobial culture. MATERIAL AND METHODS: 10 µl specimens of Staphylococcus aureus (S. aureus), Streptococcus pyogenes (S. pyogenes), Escherichia coli (E. coli) and Candida albicans (C. albicans) were cultured in 10 ml of 10-100% (wt/v) honey diluted in broth. Six types of polymicrobial microbial cultures were prepared by culturing the isolates with each other onto broth (control) and broth containing various concentrations of honey (10-100% wt/v). Microbial growth was assessed on solid plate media after 24 h incubation. RESULTS: Honey (30-70%) prevents growth of 10 µl specimens of all the isolates. Greater reduction in growth of E. coli was observed when cultured with S. aureus. Culturing of S. aureus with S. pyogenes, C. albicans, or E. coli increased its sensitivity to honey. S. aureus and S. pyogenes increased sensitivity of C. albicans to honey while E. coli and C. albicans decreased sensitivity of S. pyogenes. CONCLUSIONS: It might be concluded that honey prevents and inhibits growth of single and polymicrobial pathogenic cultures. Polymicrobial culture affects growth of the isolates and increases their sensitivity to honey.

16.
Arch Med Res ; 44(5): 352-60, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23867789

ABSTRACT

BACKGROUND AND AIMS: Candida species, especially Candida albicans, are major fungal pathogens of humans that are capable of causing superficial mucosal infections and systemic infections in humans. The aim of this study was to evaluate the jujube (Zizyphus spina-christi) honey for its in vitro inhibitory activity against pre-formed biofilm and its interference with the biofilm formation of C. albicans. METHODS: The XTT reduction assay, scanning electron microscopy (SEM) and atomic force microscopy (AFM) were employed to determine the inhibitory effect of Jujube honey on C. albicans biofilm. Changes in the infrared spectrum after treatment with honey were also determined by Fourier transform infrared (FTIR) spectroscopy. RESULTS: Jujube honey affects biofilms by decreasing the size of mature biofilms and by disruption of their structure. At a concentration of 40% w/v, it interferes with formation of C. albicans biofilms and disrupts established biofilms. The SEM and AFM results indicated that this type of honey affected the cellular morphology of C. albicans and decreased biofilm thickness. CONCLUSIONS: The present findings show that jujube honey has antifungal properties against C. albicans and has the ability to inhibit the formation of C. albicans biofilms and disrupt established biofilms.


Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Candida albicans/growth & development , Honey , Ziziphus , Analysis of Variance , Biofilms/growth & development , Candida albicans/drug effects , Candida albicans/ultrastructure , Humans , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Phytotherapy/methods
17.
J Perinatol ; 33(9): 703-6, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23636098

ABSTRACT

OBJECTIVE: To determine whether platelet infusion time affects platelet counts in thrombocytopenic newborns. STUDY DESIGN: This was a prospective randomized control study of 43 platelet transfusions given to newborns. Transfusions were randomized to run over either 30 min or 2 h. Platelet counts taken 30 min and 6 h after transfusion were compared using parametric, nonparametric, Pearson's correlation and logistic regression. RESULT: Changes in platelet counts 30 min and 6 h after transfusion were not different between the groups. Weak but significant negative correlations existed between postmenstrual age and change in platelet count at 30 min (r=-0.33, P=0.04) and 6 h (r=-0.37, P=0.018) after transfusion. There were no differences between the mean blood pressures before and after transfusion in either group. CONCLUSION: Transfusion duration does not affect post-transfusion platelet counts in newborns. Babies of lower postmenstrual age (PMA) may have better responses to platelet transfusions. Finally, platelet transfusions over both durations are well tolerated in neonates.


Subject(s)
Intensive Care, Neonatal , Platelet Transfusion , Thrombocytopenia/blood , Thrombocytopenia/therapy , Female , Humans , Infant, Newborn , Male , Platelet Count , Prospective Studies , Thrombocytopenia/etiology , Time Factors , Treatment Outcome
18.
Acta Physiol (Oxf) ; 205(3): 372-80, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22276905

ABSTRACT

AIMS: We tested the hypotheses that vasoconstrictor responses to limb dependency are: (i) greater in the leg than the arm, (ii) impaired with age and (iii) not sympathetically mediated. METHODS: Vascular responses to limb dependency (i.e. lowering the limb from heart level to 30 cm below heart level) were determined in 17 young and 17 older adults. Indices of blood flow were obtained in the brachial and popliteal arteries (Doppler ultrasound) as well as in the cutaneous circulation (forearm and calf using laser-Doppler flowmetry). Vasoconstriction was quantified by calculating the indices of vascular resistance as height corrected mean arterial pressure/limb blood velocity or skin flux. A second group of subjects repeated the limb dependency trials after acute systemic sympathetic blockade. RESULTS: Limb dependency increased vascular resistance index in the brachial artery (∆59 ± 8%; P<0.05) and popliteal artery (∆99 ± 10%; P<0.05 for change in heart level and brachial vs. popliteal) of young and older adults (∆60 + 9% brachial and ∆61 ± 7% popliteal arteries; P<0.05 for change in heart level and response in popliteal young vs. older adults). In contrast, cutaneous vasoconstrictor responses to limb dependency were similar in the forearm (∆218 ± 29% and ∆200 ± 29% for young and older adults, respectively) and calf (∆257 ± 32% and ∆236 ± 29%; all P<0.05 from heart level) of young and older adults. Vasoconstrictor responses to limb dependency were not affected by sympathetic blockade in young or older adults. CONCLUSION: These findings indicate that age-, limb-, and tissue-related differences may exist in the vasoconstrictor response to limb dependency in healthy humans, which are not sympathetically mediated.


Subject(s)
Aging/physiology , Arm/blood supply , Arm/innervation , Leg/blood supply , Leg/innervation , Sympathetic Nervous System/physiology , Vasoconstriction/physiology , Adrenergic Antagonists/pharmacology , Adult , Aged , Blood Pressure/physiology , Brachial Artery/physiology , Female , Heart Rate/physiology , Humans , Male , Middle Aged , Phentolamine/pharmacology , Popliteal Artery/physiology , Propranolol/pharmacology , Regional Blood Flow/physiology , Sympathetic Nervous System/drug effects , Vascular Resistance/physiology
19.
J Med Food ; 14(10): 1079-96, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21859350

ABSTRACT

Honey has been used as a medicine throughout the ages and has recently been reintroduced to modern medical practice. Much of the research to date has addressed honey's antibacterial properties and its effects on wound healing. Laboratory studies and clinical trials have shown that honey is an effective broad-spectrum antibacterial agent. Honey antimicrobial action explains the external and internal uses of honey. Honey has been used to treat adult and neonatal postoperative infection, burns, necrotizing fasciitis, infected and nonhealing wounds and ulcers, boils, pilonidal sinus, venous ulcers, and diabetic foot ulcers. These effects are ascribed to honey's antibacterial action, which is due to acidity, hydrogen peroxide content, osmotic effect, nutritional and antioxidants content, stimulation of immunity, and to unidentified compounds. When ingested, honey also promotes healing and shows antibacterial action by decreasing prostaglandin levels, elevating nitric oxide levels, and exerting prebiotic effects. These factors play a major role in controlling inflammation and promoting microbial control and healing processes. This article reviews data supporting the effectiveness of natural honey in eradicating human pathogens and discusses the mechanism of actions.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Antifungal Agents/therapeutic use , Antiparasitic Agents/therapeutic use , Antiviral Agents/therapeutic use , Honey , Administration, Topical , Food Storage , Humans , Wound Healing/drug effects
20.
J Perinatol ; 31(12): 785-8, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21527904

ABSTRACT

OBJECTIVE: Monitoring the changes in buccal tissue oxygen saturation (StO(2)) may aid in early diagnosis of circulatory compromise. Our objective was to define the normal value of buccal StO(2) and its correlation to the middle cerebral artery (MCA) flow indices and cardiac output in healthy term infants during the first 48 h after birth. STUDY DESIGN: In this prospective study, we assessed buccal StO(2) by visible light spectroscopy and assessed the left ventricular output (LVO) and MCA flow indices by ultrasound on postnatal days 1 and 2. We enrolled 20 term neonates. The Wilcoxon-matched pairs signed-rank test and Pearson correlation were used to analyze the data. RESULT: Median (range) buccal StO(2) readings were 68% (62 to 72) on day 1 and 66% (61 to 69) on day 2 (P=0.03). A weak but significant positive correlation was found between buccal StO(2) and LVO (r=0.37, P=0.023). There was no correlation between buccal StO(2) and MCA mean velocity or pulsatility index. CONCLUSION: Under a physiological state, buccal StO(2) in resting healthy neonates is 61 to 72%, regardless of variability in systemic and cerebral blood flow. Because of its ease of use and non-invasive nature, the use of visible light spectroscopy in conditions with circulatory compromise needs to be further investigated.


Subject(s)
Middle Cerebral Artery/physiology , Oxygen/blood , Spectrum Analysis/instrumentation , Blood Flow Velocity , Cardiac Output , Cheek/blood supply , Hemoglobins/analysis , Humans , Infant, Newborn , Middle Cerebral Artery/diagnostic imaging , Oximetry , Oxyhemoglobins/analysis , Reference Values , Ultrasonography , Ventricular Function, Left
SELECTION OF CITATIONS
SEARCH DETAIL