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1.
Rev Gastroenterol Mex (Engl Ed) ; 87(2): 176-180, 2022.
Article in English | MEDLINE | ID: mdl-34776394

ABSTRACT

INTRODUCTION AND AIMS: Viral hepatitis, which appears most frequently at birth or during childhood, is a disease whose transmission routes include tears, bile, sexual fluids, sweat, milk, urine, feces, and saliva. The aim of the present study was to analyze the specificity of the immunochromatographic and ELISA diagnostic tests for hepatitis B surface antigen and compare them with PCR testing. MATERIALS AND METHODS: The study sample was made up of 140 men and 60 women referred to the Urmia Medical University hospital to undergo PCR testing for HBV diagnosis. The ELISA test was performed using the Pioneer Medicine Company kit (Tehran, Iran). RESULTS: The results of the HBs-Ag rapid test and the ELISA test were compared with the PCR test. The HBs-Ag rapid test had 97% sensitivity and 91% specificity, whereas the ELISA test had 78% sensitivity and 76% specificity. DISCUSSION AND CONCLUSION: According to our results, the immunochromatographic test was accurate for diagnosing HBs-Ag in blood and the ELISA test had acceptable sensitivity and specificity, compared with PCR testing.


Subject(s)
Hepatitis B Surface Antigens , Hepatitis B , Chromatography, Affinity , Diagnostic Tests, Routine , Enzyme-Linked Immunosorbent Assay , Female , Hepatitis B/diagnosis , Hepatitis B virus/genetics , Humans , Infant, Newborn , Iran , Male , Polymerase Chain Reaction
2.
J Intell Mater Syst Struct ; 29(3): 438-445, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29674842

ABSTRACT

A miniature nonlinear piezoelectric energy harvester is developed to power state of the art leadless cardiac pacemakers from cardiac motions. The energy harvester is integrated in the leadless pacemaker and is connected to the myocardium. The energy harvester converts myocardial motions to electricity to power leadless pacemakers. The energy is stored in a battery or supercapacitor and is used for pacing. The device is composed of a bimorph piezoelectric beam confined in a gray iron frame. The system is assembled at high temperature and operated at the body temperature. The mismatch in the coefficients of thermal expansion of the beam and the frame causes the beam to buckle in body temperature. This intentional buckling makes the beam unstable and improves the power production and robustness of the device. Having high natural frequency is a major problem in microelectromechanical systems energy harvesters. Considering the small size of the energy harvester, 0.5 cm3, the natural frequency is expected to be high. In our design, the natural frequency is lowered significantly using a buckled beam and a proof mass. Since the beam is buckled, the design is bistable and nonlinear, which could increase the output power. In this article, the device is analytically modeled, and the natural frequencies and mode shapes of the energy harvester are analytically derived. The terms corresponding to geometric nonlinearities are included in the electromechanical coupled governing equations. The simulations show that the device generates sufficient electricity to power leadless pacemakers.

3.
J Postgrad Med ; 64(1): 40-46, 2018.
Article in English | MEDLINE | ID: mdl-29067921

ABSTRACT

Ultraviolet (UV) irradiation is one of the several environmental hazards that may cause inflammatory reactions in ocular tissues, especially the cornea. One of the important factors that affect how much ultraviolet radiation (UVR) humans are exposed to is travel. Hence, traveling is considered to include a more acute UVR effect, and ophthalmologists frequently evaluate and manage the ocular manifestations of UV irradiation, including UV-induced keratitis. The purpose of this paper is to provide an evidence-based analysis of the clinical effect of UVR in ocular tissues. An extensive review of English literature was performed to gather all available articles from the National Library of Medicine PubMed database of the National Institute of Health, the Ovid MEDLINE database, Scopus, and ScienceDirect that had studied the effect of UVR on the eye and its complications, between January 1970 and June 2014. The results show that UVR at 300 nm causes apoptosis in all three layers of the cornea and induces keratitis. Apoptosis in all layers of the cornea occurs 5 h after exposure. The effect of UVR intensity on the eye can be linked to numerous factors, including solar elevation, time of day, season, hemisphere, clouds and haze, atmospheric scattering, atmospheric ozone, latitude, altitude, longitudinal changes, climate, ground reflection, and geographic directions. The most important factor affecting UVR reaching the earth's surface is solar elevation. Currently, people do not have great concern over eye protection. The methods of protection against UVR include avoiding direct sunlight exposure, using UVR-blocking eyewear (sunglasses or contact lenses), and wearing hats. Hence, by identifying UVR intensity factors, eye protection factors, and public education, especially in travelers, methods for safe traveling can be identified.


Subject(s)
Cornea/radiation effects , Keratitis/diagnosis , Sunlight/adverse effects , Ultraviolet Rays/adverse effects , Cornea/pathology , Corneal Diseases/etiology , Humans , Keratitis/etiology , Radiation Injuries
4.
Smart Mater Struct ; 26(6)2017 Jun.
Article in English | MEDLINE | ID: mdl-29674807

ABSTRACT

This paper studies the fabrication and testing of a magnet free piezoelectric energy harvester (EH) for powering biomedical devices and sensors inside the body. The design for the EH is a fan-folded structure consisting of bimorph piezoelectric beams folding on top of each other. An actual size experimental prototype is fabricated to verify the developed analytical models. The model is verified by matching the analytical results of the tip acceleration frequency response functions (FRF) and voltage FRF with the experimental results. The generated electricity is measured when the EH is excited by the heartbeat. A closed loop shaker system is utilized to reproduce the heartbeat vibrations. Achieving low fundamental natural frequency is a key factor to generate sufficient energy for pacemakers using heartbeat vibrations. It is shown that the natural frequency of the small-scale device is less than 20 Hz due to its unique fan-folded design. The experimental results show that the small-scale EH generates sufficient power for state of the art pacemakers. The 1 cm3 EH with18.4 gr tip mass generates more than16 µW of power from a normal heartbeat waveform. The robustness of the device to the heart rate is also studied by measuring the relation between the power output and the heart rate.

5.
Anatol J Cardiol ; 17(3): 176-183, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27752030

ABSTRACT

OBJECTIVE: Chronic anabolic androgenic steroid (AAS) consumption increases incidence of cardiovascular abnormalities in athletes and mechanisms underlying those abnormalities continue to be investigated. This study examines whether nandrolone consumption induced cardiac and coronary artery wall abnormalities via oxidative stress. It was also designed to determine whether enforced swimming augmented possible cardiotoxic effects of nandrolone in rat heart. METHODS: Twenty-four male Wistar rats were divided into 3 groups: control, nandrolone, and nandrolone with enforced swimming. Nandrolone group received 10 mg/kg body weight nandrolone 3 times a week for 6 weeks. Nandrolone group with enforced swimming received the same amount of nandrolone and was forced to swim with excess weight of 20% body weight. RESULTS: After 6 weeks of treatment, results indicated proliferation of heart muscle and coronary smooth muscle cells and lipid peroxidation; significant rise in levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), nicotinamide adenine dinucleotide phosphate oxidase, homocysteine (Hcy), apolipoprotein B, low-density lipoprotein, and cholesterol, as well as severe fibrosis in heart tissue and around coronary arteries of nandrolone and nandrolone with enforced swimming groups compared with control group. CONCLUSION: These findings strongly support idea that nandrolone intake by sedentary rats and exercised rats induced heart abnormality mediated by oxidative stress, which was manifest in increased lipid peroxidation, Hcy, and 8-OHdG in heart tissue.


Subject(s)
Androgens/pharmacology , Coronary Vessels/drug effects , Myocardium/metabolism , Nandrolone/pharmacology , Swimming , Androgens/blood , Animals , Cholesterol/blood , Male , Nandrolone/blood , Rats , Rats, Wistar
6.
Transplant Proc ; 43(7): 2741-6, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21911156

ABSTRACT

This study was designed to clarify the molecular mechanism(s) of mycophenolate mofetil (MMF)- induced gastrointestinal (GI) disorders. Forty-two adult Wistar rats were assigned to 7 groups including control and test hosts. The control animals received normal saline and the test animals various doses of MMF (10, 20, or 40 mg/kg) for 14 days, or MMF, aspirin, or lipopolysaccharide as single high doses (40, 200, and 1 mg/kg, respectively). To evaluate the GI disorders, are determined body weight gain, serum level of alkaline phosphatase (ALP), nitric oxide (NO), and acute phase proteins (APP). Additionally, we measured the duodenal NO content and myeloperoxidase activity. MMF administration resulted in a significant (P < .05) body weight loss and elevation of serum levels of ALP and NO. The duodenal NO content increased in the test groups with the highest levels among the aspirin-treated cohort. The myeloperoxidase activity and the serum level of APP were elevated among MMF- and aspirin-treated animals. Histopathologic examinations showed villous atrophy and inflammatory cells infiltration among MMF-treated animals. Our data suggested that the MMF-induced GI disorders were likely related to local inflammatory reactions, which may be attributed to elevated NO and myeloperoxidase activities that result in pathological injuries. Moreover, the biochemical alterations and histopathologic injuries due to MMF administration were similar to aspirin-induced local disorders rather than to lipopolysaccharide-induced systemic damage.


Subject(s)
Acute-Phase Proteins/physiology , Gastrointestinal Diseases/chemically induced , Immunosuppressive Agents/adverse effects , Mycophenolic Acid/analogs & derivatives , Nitric Oxide/physiology , Acute-Phase Proteins/metabolism , Animals , Dose-Response Relationship, Drug , Duodenum/enzymology , Duodenum/metabolism , Electrophoresis, Capillary , Mycophenolic Acid/adverse effects , Nitric Oxide/blood , Nitric Oxide/metabolism , Peroxidase/metabolism , Rats , Rats, Wistar , Up-Regulation
7.
Pak J Biol Sci ; 12(2): 134-9, 2009 Jan 15.
Article in English | MEDLINE | ID: mdl-19579933

ABSTRACT

In order to determine zinc and catalase content of seminal plasma in the buffalo and to study their associations with the semen characteristics, 54 semen samples were collected from 10 buffalo bulls; semen volume and sperm concentration, gross and progressive motility and viability were evaluated, seminal plasma was then harvested by centrifugation and its zinc content was estimated by atomic absorption spectrophotometer and its catalase activity determined by using a commercial kit. The zinc content of the seminal plasma (Mean +/- SEM) was recorded as 154.40 +/- 1.74 mg L(-1), while, the mean catalase value was 32.00 +/- 0.42 U mL(-1). The mean zinc values was highly correlated with sperm progressive motility and viability and with catalase values (p = 0.000 for all) and also was associated with gross motility (p = 0.020) and negatively with abnormal morphology (p = 0.049). The catalase values were highly associated with sperm progressive motility, viability and zinc content (p = 0.000 for all) and was associated with sperm gross motility (p = 0.024). For further clarification of these correlations, the samples were categorized in three groups of excellent (Ex, >90% motile, n = 33), good (Go, 80-89% motile, n = 15) and moderate (Mo, <79% motile, n = 6) according to their percentage of sperm motility. The mean progressive motility in Ex group was 92.54 +/- 0.51%, in Go group was 81.66 +/- 0.62% and in Mo group was 71.66 +/- 1.05%. The mean zinc and catalase values were recorded as 161.07 +/- 1.63 mg L(-1) and 33.41 +/- 0.34 U mL(-1) in Ex, 146.70 +/- 1.91 mg L(-1) and 31.01 +/- 0.67 in Go and 136.42 +/- 4.97 mg L(-1) and 26.51 +/- 0.87 U mL(-1) in Mo groups. The mean zinc value in Ex group was highly associated with sperm motility, viability and catalase values, in Go group was associated with catalase values and highly associated with sperm abnormal morphology and in Mo group it was highly associations with catalase values only. The mean catalase value in Ex group, was highly associated with sperm motility and viability, in Go group was associated with zinc content and in Mo groups was highly associated with the zinc content. These results show that seminal plasma zinc and catalase content are correlated with semen characteristics and synergistically act to preserve motility and viability of the spermatozoa after ejaculation.


Subject(s)
Buffaloes , Catalase/metabolism , Semen/chemistry , Zinc/analysis , Animals , Male , Semen Analysis , Semen Preservation , Sperm Count , Sperm Motility
8.
Singapore Med J ; 50(6): 610-3, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19551315

ABSTRACT

INTRODUCTION: The aim of this study was to investigate the relationship between serum apolipoprotein A-I (apoA-I) and apolipoprotein B (apoB) and the severity of coronary artery stenosis. METHODS: This case-control study was carried out on 106 patients who underwent angiography and 100 healthy controls. ApoA-I and apoB as well as the serum total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglyceride and low-density lipoprotein cholesterol (LDL-C) levels were measured. Very low-density lipoprotein cholesterol levels and the LDL-C/HDL-C ratio were calculated. RESULTS: In an Iranian population with coronary artery disease (79 men and 27 women, aged 53 +/- 8.5 years), the increased levels of apoA-I and apoB were correlated with the number of involved vessels and the severity of coronary lesions. However, no significant correlation was found between the serum values of lipids as well as other lipoproteins and the number of vessels involved and the severity of coronary lesions. CONCLUSION: ApoA-I and apoB are indicated as risk factors for cardiovascular and, possibly, cerebrovascular diseases. From this study, it may be concluded that apoA-I and apoB serum concentration levels are independent risk factors for coronary atherosclerosis in the Iranian population. It also demonstrates a direct relationship between the severity of coronary atherosclerosis and the number of lesions in the involved vessels. It can be regarded as an index for the relationship of apoA-I and apoB to the early, still clinically asymptomatic, steps of the pathogenesis of coronary disease.


Subject(s)
Apolipoprotein A-I/blood , Apolipoproteins B/blood , Coronary Artery Disease/blood , Aged , Aged, 80 and over , Case-Control Studies , Cholesterol, HDL/metabolism , Cholesterol, LDL/metabolism , Coronary Artery Disease/diagnosis , Female , Humans , Iran , Male , Middle Aged , Risk Factors , Triglycerides/metabolism
9.
Indian J Clin Biochem ; 24(4): 356-60, 2009 Oct.
Article in English | MEDLINE | ID: mdl-23105860

ABSTRACT

Improving specimen quality as well as healthcare worker (HCW) safety poses significant concerns for today's laboratories. With an increasing number of diagnostic tests requested, laboratory professionals are faced with challenges to reduce laboratory errors, improve the quality of laboratory results to assure accurate diagnosis and implement initiatives to ensure healthcare worker safety and minimize risk of exposure to bloodborne pathogens. A prior study conducted in 2008 reported that variations in blood collection methods for clinical chemistry assays may affect overall specimen quality. As a follow up, the current study assessed the quality of 22563 patient specimens for cell counting in EDTA blood collection tubes that were obtained with needle and syringe collection (open) using either disposable tubes or re-washed glass vials or with an evacuated blood collection system (closed). Based on the observations, the use of the evacuated blood collection system resulted in better preanalytical specimen quality as compared with needle and syringe collection. The findings also showed an approximately 70-fold reduction in the incidence of clotting as well as fewer instrument-generated flags using the evacuated collection system. In addition, the use of an evacuated collection system for venous blood collection demonstrated lesser chance of blood exposure to healthcare workers.

10.
World J Gastroenterol ; 13(32): 4340-4, 2007 Aug 28.
Article in English | MEDLINE | ID: mdl-17708608

ABSTRACT

AIM: To investigate the effect of vitamin E on oxidative stress status in the small intestine of diabetic rats. METHODS: Twenty-four male Wistar rats were randomly divided into three groups: Control (C), non-treated diabetic (NTD) and vitamin E-treated diabetic (V(E)TD) groups. The increases in lipid peroxidation, protein oxidation and superoxide dismutase (SOD) in these three groups was compared after 6 wk. RESULTS: There was no significant difference in catalase activity between NTD and control rats. Compared to NTD rats, the treatment with vitamin E significantly decreased lipid peroxidation and protein oxidation, and also increased catalase activity and SOD. CONCLUSION: The results revealed the occurrence of oxidative stress in the small intestine of diabetic rats. Vitamin E, as an antioxidant, attenuates lipid peroxidation and protein oxidation, and increases antioxidant defense mechanism.


Subject(s)
Antioxidants/pharmacology , Diabetes Mellitus, Experimental/physiopathology , Intestine, Small/physiopathology , Oxidative Stress/drug effects , Vitamin E/pharmacology , Animals , Catalase/metabolism , Intestine, Small/drug effects , Lipid Peroxidation/drug effects , Male , Random Allocation , Rats , Rats, Wistar , Streptozocin , Superoxide Dismutase/metabolism
11.
Anim Reprod Sci ; 102(3-4): 308-13, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17433580

ABSTRACT

The objective of this study was to evaluate the protein profiles of seminal plasma in buffalo bulls and to examine their correlation with semen characteristics. Semen of 10 buffalo bulls were collected by a bovine artificial vagina. Semen characteristics (motility, morphology, viability and concentration) were recorded. A part of the semen sample (1 ml) was diluted by tris-egg yolk-glycerol extender, packed in French straws and was frozen in liquid nitrogen. The straws were later thawed and semen characteristics were compared with those of the fresh semen. Seminal plasma was harvested by centrifugation; treated with cold ethanol and then, underwent SDS-polyacrylamide gel electrophoresis (PAGE). Twenty five protein bands were identified on the gel, of which those of <35.5 kDa were prominent (72% of the bands). Of these protein fractions, 24.5 kDa was significantly correlated with sperm progressive motility in fresh and viability in frozen-thawed semen while 45 kDa bands were correlated with abnormal morphology in frozen-thawed semen; 55 kDa protein fractions were correlated with sperm viability of fresh semen. Progressive motility, viability and abnormal sperm morphology of frozen-thawed semen were highly correlated with these parameters in the fresh semen. In conclusion, seminal plasma protein fractions in buffalo bulls are similar to those reported in other animal species and have some correlations with semen characteristics before and after freezing.


Subject(s)
Buffaloes , Cryopreservation/veterinary , Electrophoresis, Polyacrylamide Gel , Proteins/analysis , Semen Preservation/veterinary , Semen/chemistry , Animals , Chemical Fractionation , Male , Semen/physiology , Sperm Motility , Spermatozoa/abnormalities
13.
Environ Monit Assess ; 89(3): 243-61, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14632093

ABSTRACT

Performance evaluation of two reverse osmosis (RO) desalination plants (DSP) at villages: Melasirupodhu (30 m3 day(-1)) and Sikkal (50 m3 day(-1)) in Ramanathpuram district, Tamil Nadu (India) were studied so as to bring out the state-of-art of their operation and maintenance (O&M). Detailed information on plant design and engineering, water quality, plant personnel, and cost of O&M was collected for a period of three years after commissioning of the two plants. Feed water was brackish, the TDS varied in the range of 6500-8500 mg L(-1) at Melasirupodhu and 5300-7100 mg L(-1) at Sikkal villages. The product water quality was observed to be gradually deteriorating as the salt rejection by the membranes decreased with time. The salt rejection was 97-99% at the time of commissioning of the plants, and came down to 89-90% at the end of 3 years of operation. Product water TDS soon after installation of the plants was excellent and within desirable limits of BIS. After three years of operation, few parameters exceeded the desirable limits, however, they were found to be within permissible limits of BIS. The analyses of the data showed that both plants were operated only at 30-36% of the design capacity. Plant shut-down due to inadequate and erratic power supply, and plant break-down and inherent delay in repairs due to lack of adequate infrastructure were found to be the major causes for the low utilization of the plants. Consequently the recurring cost of product water production enhanced to Rs. 25.0/m3 at Melasirupodhu and Rs. 17.5 m(-3) at Sikkal, as against the estimated cost of Rs. 15.0/m3 and Rs. 11.0/m3, respectively, as per the design. Over the years, the energy consumption for the product water output increased reflecting higher operational pressures needed with the aging of the membranes.


Subject(s)
Developing Countries , Waste Disposal, Fluid/methods , Water Purification/methods , Conservation of Energy Resources , Costs and Cost Analysis , Engineering , India , Membranes, Artificial , Osmosis , Rural Population , Sodium Chloride/isolation & purification
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