Matrix metalloproteinase-3, vitamin D receptor gene polymorphisms, and occupational risk factors in lumbar disc degeneration.

BACKGROUND: Lumbar disc degeneration (LDD) is a process that begins early in life, contributing to the development of low back pain. LDD is a consequence of a variety of factors, and its etiology remains poorly understood. Objectives to investigate occupational and genetic risk factors inducing lumbar disc degeneration, and to evaluate the possible association of genetic polymorphisms of matrix metalloproteinase 3 (MMP-3) and vitamin D receptor (VDR) with the severity of LDD in an Egyptian population. SUBJECTS AND METHODS: A case control study involving 84 LDD and 60 controls was carried out. Five types of work related factors were investigated by questionnaire, complete neurological examination for all subjects and MRI for the cases. Polymerase chain reaction and restriction fragment length polymorphism methods were applied to detect polymorphisms in MMP-3 Promoter (-1,171 6A/5A) (rs 731236) and VDR-Apa (rs 35068180). RESULTS: We found that family history, back injury, smoking, high level of sitting, bending/twisting, physical workload, lifting, whole body vibration, mutant allele 5A of MMP-3 and mutant allele T of VDR were significantly associated with LDD (OR = 2.9, 3.1, 2.1, 11.1, 15.9, 11.7, 8.2, 12.6, 2.5 and 3.1 respectively, p < 0.05). Cases that carry allele 5A and/or allele T were associated with LDD severity. CONCLUSION: LDD is closely associated in occurrence and severity with occupational, environmental risk factors and susceptibility genes namely MMP-3, and VDR (ApaI). This study throws light on the importance of screening for early detection of susceptible individuals and disease prevention.

Improved reversed-phase liquid chromatographic method combined with pulsed electrochemical detection for the analysis of amikacin.

A two-step gradient liquid chromatographic method combined with pulsed electrochemical detection is described for the determination of amikacin and its impurities. The mobile phase is composed of an aqueous solution containing 1.8 g/l sodium 1-octanesulphonate, 14 ml/l tetrahydrofuran, 50 ml/l of phosphate buffer pH 3.0 and sodium sulphate, which was 20 g/l in mobile phase A and 28 g/l in mobile phase B. 0.5 M sodium hydroxide was added post-column to enhance the detection. An investigation of different reversed-phase columns indicated that the Discovery (C18, 5 microm, 250 mm x 4.6 mm i.d.) column was the most suitable. Compared to previously published investigations, the proposed method showed higher sensitivity and efficiency, allowing the separation of the main component amikacin from 16 impurities, 7 of which were of unknown identity. A central composite experimental design was used to assess the robustness. The method showed good repeatability and linearity in the assay range. The method was further applied to analyze some commercial samples.

Analysis of neomycin using an improved liquid chromatographic method combined with pulsed electrochemical detection.

An isocratic liquid chromatographic method with pulsed electrochemical detection is described for the determination of neomycin in the presence of its impurities. The mobile phase is composed of an aqueous solution containing 35 g/l of sodium sulphate, 1 g/l of sodium 1-octanesulfonate, 14 ml/l of tetrahydrofuran (THF) and 50 ml/l of 0.2 M phosphate buffer pH 3.0. Sodium hydroxide was added post column to enhance the detection. An investigation of different reversed-phase columns indicated that the Discovery (C18 5 microm, 250 mm x 4.6 mm I.D.) column was the most suitable. The proposed method shows high efficiency, allowing the separation of the main component neomycin B from neomycin C and 15 other impurities. A central composite design was used to assess the robustness of the method. The method showed good selectivity, repeatability, linearity and sensitivity. This method was applied to analyse commercial samples.

Improved LC of minocycline drug substance.

An isocratic liquid chromatographic method is described for the separation of minocycline and its impurities. This method uses XTerra RP-18, 5 microm (25 cm x 4.6 mm I.D.), a silica-based stationary phase with reduced silanol activity. A mobile phase composed of acetonitrile-0.2 M tetrabutylammonium hydrogen sulphate pH 6.5-0.2 M ethylenediaminetetraacetic acid pH 6.5-water (20:20:20:40; v/v/v/v) was used at a flow rate of 1 ml/min. The column temperature was set at 35 degrees C. UV detection was performed at 280 nm. Optimisation of the separation method and a robustness study were performed by means of a central composite experimental design. The method allows to separate minocycline from known impurities. Some unidentified impurities are also separated. The total time of analysis is less than 20 min.

Determination of meloxicam in bulk and pharmaceutical formulations.

Three sensitive and reproducible methods for quantitative determination of meloxicam (mel) in pure form and in pharmaceutical formulations are presented. The first method is high performance liquid chromatography by which the drug is determined in the presence of its degradation products over concentration range 100-500 microg x ml(-1) with mean percentage accuracy 100.13+/-0.53. The second method is based on measuring the absorbance of the formed neutral complex between basic methylene blue and mel in phosphate buffer (pH 8) at lambda=653.5 nm over concentration range 1-5 microg x ml(-1) with mean percentage accuracy 99.12+/-1.18. The third method is based on reaction between 2,3-dichloro-5,6-dicyano-p-benzoquinone resulting in the formation of an intense orange red coloured product after heating in a boiling water bath for 5 min. The coloured product exhibits an absorption maximum at 455 nm, over concentration range 40-160 microg x ml(-1) with mean percentage accuracy 100.53+/-1.04.

Determination of aceclofenac in bulk and pharmaceutical formulations.

Three sensitive and reproducible methods for quantitative determination of aceclofenac (AC) in pure form and in pharmaceutical formulation are presented. The first method is based on the reaction between the drug via its secondary aromatic amino group and p-dimethylaminocinnamaldehyde (PDAC) in acidified methanol to give a stable coloured complex after heating at 75 degrees C for 20 min. Absorption measurements were carried out at 665.5 nm. Beer's law is obeyed over concentration range 20-100 microg ml(-1) with mean recovery 100.33 +/- 0.84. The other two methods are high performance liquid chromatography (HPLC) and densitometric methods by which the drug was determined in the presence of its degradation products over concentration range of 20-70 microg ml(-1) and 1-10 microg per spot and mean recoveries are 99.59 +/- 0.90 and 99.45 +/- 1.09, respectively.

Occupational exposure to aluminum and its amyloidogenic link with cognitive functions.

As many other metals, aluminum is a widely recognized neurotoxicant and its link with neurodegenerative disorders has been the subject of scientific debate. One proposal focuses on amyloid ß deposition (amyloidogenesis) as the key player in triggering neuronal dysfunction the so-called amyloid cascade hypothesis. We undertook this study first to investigate the cognition status of workers exposed to Al dust in an Al factory in Southern Cairo, second, to evaluate serum amyloid precursor protein (APP) and cathepsin D (CD) enzyme activity to study the possible role of Al in amyloidogenesis, and finally to explore the relation between these potential biomarkers and cognitive functions. The study was conducted on 54 exposed workers and 51 matched controls. They were subjected to questionnaire, neurological examination and a cognitive test battery, Addenbrooke's Cognitive Examination - Revised (ACE-R). Serum Al, APP and CD enzyme activity were measured. A significant increase of serum Al was found in the exposed workers with an associated increase in serum APP and decrement in CD activity. The exposed workers displayed poor performance on the ACE-R test. No significant correlation was detected between ACE-R test total score and either APP or CD activity. We concluded that occupational exposure to Al is associated with cognitive impairment. The effect of occupational Al exposure on the serum levels of APP and CD activity may be regarded as a possible mechanism of Al in amyloidogenesis. However, our findings do not support the utility of serum APP and CD activity as screening markers for early or preclinical cognitive impairment.

Sharps injuries among health care workers in Cairo University Hospitals.

BACKGROUND: Health care workers (HCWs) are exposed to blood borne pathogens, through job-related risk factors like sharps injuries (SIs). Sharps injuries can be prevented by safer devices and through education and training of universal precautions and safe work practices. OBJECTIVES: The present study aims to examine the current situation of infection control at Cairo University Hospitals in Egypt, through studying SIs among health care workers and evaluating the preventive measures. SUBJECTS AND METHODS: The first part of this study was cross-sectional in design. A self-administered Arabic questionnaire was designed for this study based on EPINet (Exposure Prevention Information Network) Needle Stick and Sharps injuries reporting Sheet. The second part of the study was an interventional design to evaluate the effectiveness of preventive measures which were introduced since the beginning of 2011. RESULTS: Forty percent of the participants (416/1036) reported at least one sharps injury in the preceding year (2010), of which more than 70% (293/416) experienced more than one injury. 88.9% (370/416, p < 0.001) of HCWs did not report their injury. Following intervention measures injury rates were significantly reduced from 36.9/100 person in 2010 in the intensive care units, to 12.4/100 person during 2011, (X2 = 21.419 and P value < 0.001). CONCLUSION: There is a high occurrence of sharps injuries in Cairo University Hospitals. Implementation of safety devices and adequate training will lead to reduction of SIs among HCWs.

Effect of occupational exposure to elemental mercury in the amalgam on thymulin hormone production among dental staff.

Occupational exposure of dental staff to elemental mercury vapor released from dental amalgam is an issue of concern because of the possible immunological and neurological adverse outcomes. Recently, studies have reported that inorganic mercury induces immunosuppression by decreasing the production of thymus gland hormone (thymulin). This study aimed at investigating mercury body burden in dental staff and the relation of this burden to the potential impact of mercury on thymus gland hormone level (thymulin). Besides, the work aimed at verifying mercury effect on nitric oxide synthetase as a possible mechanism of its immunotoxicity. The study population consisted of a group of dental staff (n = 39) [21 dentists and 18 nurses] and a matched control group (n = 42). Each individual was subjected to detailed occupational and medical history taking and to estimation of urinary mercury (U-Hg) and blood mercury (B-Hg) as indicators of mercury body burden and exposure, respectively. Measurement of total thymulin hormone blood level, and plasma level of nitrite and nitrate (indicators of nitric oxide) was also done. The study showed a significantly increased U-Hg and B-Hg levels in the dental staff compared to their controls. This elevation of mercury body burden was associated with significant reduction in thymulin hormone blood level and nitric oxide parameters. These results were more evident in the group of nurses compared to the dentists. In conclusion, our results show that dentists and dental nurses have significant exposure to mercury vapor and point to the negative impact of mercury on thymus gland functions and confirm the implication that the nitric oxide pathway is a possible mechanism for this impact. Moreover, the study raises attention to the importance of hygiene measures in reduction of exposure to mercury vapor released from dental amalgam.