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101.
102.
Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph. 相似文献
103.
BACKGROUND: The Personal Health Questionnaire (PHQ) was developed to screen for depressive disorder in an English speaking population. Its validity in Urdu speaking people of Pakistani family origin living in UK is yet to be established. METHODS: The PHQ was used to screen for depression in a two phase primary care based study of depressive disorder in people of Pakistani family origin residing in Manchester, UK. A proportion of high scorers (PHQ> or =7) and a random selection of low scorers (PHQ 0-6) were interviewed with the Psychiatric Assessment Schedule (PAS) to confirm caseness (ID> or =5). A receiver operator characteristic curve (ROC) analysis was carried out to confirm the optimum threshold value. RESULTS: The PHQ was used to screen 218 subjects with cut off of PHQ> or =7. 46 high scorers and 31 low scorers were interviewed in second stage using PAS. At this threshold PHQ has a sensitivity of 70.4% and specificity of 89.3%. CONCLUSIONS: Findings of this study confirm high sensitivity and specificity of PHQ amongst people of Pakistani family origin. It can be used as a screening instrument to detect depression in Urdu speaking population in UK. 相似文献
104.
Tayyaba Ali Muhammad Ismail Farkhanda Asad Asma Ashraf Usman Waheed Qaiser M. Khan 《Drug and chemical toxicology》2018,41(2):213-220
To control agricultural pests and meet the increasing food demands, pesticides use has been increased substantially over time. Although pesticides are relatively specific to their targets, they can affect non-target organisms and are hazardous for the population around the application areas particularly to the individuals engaged in different types of agricultural activities. This situation is worse in developing and under-developed countries where personal protective equipment is merely used and regulatory guidelines are hardly practiced. In the present study, DNA damage in women exposed to pesticides while picking cotton with bare hands was assessed using single cell gel electrophoresis assay or comet assay. The presence of pesticides in blood serum of exposed individuals was also analyzed using high-performance liquid chromatography. Blood samples were collected from 138 (69 exposed and 69 control) randomly selected females from a major cotton growing area (Bahawalpur District) of the Punjab province of Pakistan. DNA damage, as determined by the mean comet tail length, was significantly higher (p?0.001) in the exposed group compared to the unexposed. A positive correlation of DNA damage with age and exposure time was also observed. Residues of three pesticides, cyhalothrin, endosulfan, and deltamethrin found significantly higher (p?0.001) in the serum samples of the exposed group compared to the unexposed. It was observed that the groups with higher mean comet tail length also had a higher concentration of pesticides in their serum samples indicating a positive association of DNA damage and pesticide exposure. The present study suggests that exposure to pesticides leads to DNA damage. 相似文献
105.
Asuka Ito Mostofa Jamal Kiyoshi Ameno Naoko Tanaka Ayaka Takakura Takanori Miki 《Drug and chemical toxicology》2018,41(2):245-247
Carbon monoxide (CO) produces several neurological effects, including cognitive, mood, and behavioral disturbance. Glutamate is thought to play a particularly important role in learning and memory. Thus, the present study was aimed at investigating the local effect of CO on the glutamate level in the hippocampus of mice using in vivo reverse microdialysis. Mice were perfused with Ringer’s solution (control) or CO (60–125?μM) in Ringer’s solution into the hippocampus via microdialysis probe. Dialysate samples were collected every 20?min, and then analyzed with high-performance liquid chromatography coupled to an electrochemical detector. The result revealed that the perfusion with CO had no significant effect on glutamate levels (p?=?0.316) as compared to the control group. This finding does not support a local CO rise as the cause of the increased glutamate level in the hippocampus of mice. 相似文献
106.
It has been previously shown that the interaction of some weakly basic drugs with oppositely charged fatty acids during digestion can influence the solid-state form of the drug if it precipitates. The present study hypothesized the opposite effect for weakly acidic drugs. Tolfenamic acid (TA) and an oppositely charged cationic surfactant, didodecyldimethylammonium bromide (DDAB) were combined in a model medium chain lipid formulation. The phase distribution upon in vitro lipolysis was determined using HPLC and the solid-state form of precipitated TA was determined using X-ray diffraction and crossed polarized light microscopy. TA precipitated in a different polymorphic crystalline form to the starting reference material in the absence of DDAB but precipitated in an amorphous form when DDAB was included in the same formulation. The solubility of TA upon dispersion and digestion of the formulation was considerably higher in the presence of DDAB. The findings point to ionic interactions between TA and DDAB as the reason for the improved drug solubility throughout digestion, and precipitation of drug in an amorphous salt form, analogous to what has been observed in the past for some poorly water-soluble weakly basic drugs with anionic co-formers. 相似文献
107.
Mechanisms of toxicity associated with six tyrosine kinase inhibitors in human hepatocyte cell lines
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Cécile Mingard Franziska Paech Jamal Bouitbir Stephan Krähenbühl 《Journal of applied toxicology : JAT》2018,38(3):418-431
Tyrosine kinase inhibitors have revolutionized the treatment of certain cancers. They are usually well tolerated, but can cause adverse reactions including liver injury. Currently, mechanisms of hepatotoxicity associated with tyrosine kinase inhibitors are only partially clarified. We therefore aimed at investigating the toxicity of regorafenib, sorafenib, ponatinib, crizotinib, dasatinib and pazopanib on HepG2 and partially on HepaRG cells. Regorafenib and sorafenib strongly inhibited oxidative metabolism (measured by the Seahorse‐XF24 analyzer) and glycolysis, decreased the mitochondrial membrane potential and induced apoptosis and/or necrosis of HepG2 cells at concentrations similar to steady‐state plasma concentrations in humans. In HepaRG cells, pretreatment with rifampicin decreased membrane toxicity (measured as adenylate kinase release) and dissipation of adenosine triphosphate stores, indicating that toxicity was associated mainly with the parent drugs. Ponatinib strongly impaired oxidative metabolism but only weakly glycolysis, and induced apoptosis of HepG2 cells at concentrations higher than steady‐state plasma concentrations in humans. Crizotinib and dasatinib did not significantly affect mitochondrial functions and inhibited glycolysis only weakly, but induced apoptosis of HepG2 cells. Pazopanib was associated with a weak increase in mitochondrial reactive oxygen species accumulation and inhibition of glycolysis without being cytotoxic. In conclusion, regorafenib and sorafenib are strong mitochondrial toxicants and inhibitors of glycolysis at clinically relevant concentrations. Ponatinib affects mitochondria and glycolysis at higher concentrations than reached in plasma (but possibly in liver), whereas crizotinib, dasatinib and pazopanib showed no relevant toxicity. Mitochondrial toxicity and inhibition of glycolysis most likely explain hepatotoxicity associated with regorafenib, sorafenib and possibly pazopanib, but not for the other compounds investigated. 相似文献
108.
Outcomes of low‐weight patients with avoidant/restrictive food intake disorder and anorexia nervosa at long‐term follow‐up after treatment in a partial hospitalization program for eating disorders
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109.
OBJECTIVES: Triclosan is in widespread use in domestic, commercial and healthcare settings and is used to reduce methicillin-resistant Staphylococcus aureus (MRSA) load in carriers. Triclosan resistance is uncommon, usually being due to mutation in fabI or overexpression of efflux pumps. This study investigated the ability of triclosan-containing silicone elastomer to kill MRSA adherent to its surface. METHODS: Silicone discs containing triclosan were prepared by a matrix-expansion method previously described. Discs were exposed to three strains of MRSA for 1 h for adhesion to take place. After incubation, discs were removed at intervals, sonicated and the sonicates analysed by chemiluminescence and viable counting. Survivors were found to consist of small colony variants (SCVs). These were then subjected to tests for known SCV characteristics and for susceptibility to triclosan. RESULTS: Viable counts fell until 51 h, when they began to increase, due to SCV. Of the three SCV strains, two showed impaired coagulase production and all showed reduced deoxyribonuclease production. None was auxotrophic. MICs of triclosan in the SCV rose by between 8- and 67-fold. CONCLUSIONS: Prolonged exposure of MRSA to triclosan-impregnated silicone, as in 'antimicrobial' plastics or catheters, resulted in the induction of SCV status and triclosan resistance. This has implications for industrial, medical and domestic use of polymers containing triclosan. SCVs are pathogenic and persistent. The widespread use of triclosan could lead to infection with MRSA SCVs, and new antimicrobials with physiological targets similar to that of triclosan might give rise to SCV resistance in clinical use. 相似文献
110.
Bayston R Nuradeen B Ashraf W Freeman BJ 《The Journal of antimicrobial chemotherapy》2007,60(6):1298-1301
OBJECTIVES: Propionibacterium acnes is increasingly recognized as a cause of delayed infection after spinal instrumentation or shunting for hydrocephalus. Biofilm development by this organism has recently been demonstrated. We therefore investigated the effect of two different courses of three antibiotics (penicillin, rifampicin and linezolid) on mature P. acnes biofilms in vitro. Outcomes were eradication or regrowth after withdrawal of antibiotics, simulating successful treatment and relapse. METHODS: P. acnes biofilms were grown on titanium discs for 6 days until mature, then exposed to the antibiotics for either 7 or 14 days before sonication and culture. Further, discs were similarly exposed, but after each course, they were reincubated for a further 9 days to check for regrowth. RESULTS: Penicillin, linezolid and linezolid plus rifampicin eradicated P. acnes biofilms after 14 days, but only penicillin had this effect after 7 days. 'Relapse' was prevented only by 14 day courses of penicillin or linezolid plus rifampicin, but not by linezolid alone. CONCLUSIONS: For P. acnes spinal instrumentation infections, either penicillin or linezolid plus rifampicin might be equally effective. For shunt infections, as penicillin does not give therapeutic cerebrospinal fluid concentrations, rifampicin plus linezolid might be the treatment of choice. Linezolid alone appears not to be as effective as penicillin against P. acnes biofilms. 相似文献