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Adam J. Singer MD Steve A. McClain MD Alexander Romanov DVM Jean Rooney BS Tom Zimmerman DVM 《Academic emergency medicine》2007,14(12):1125-1129
Objectives Cutaneous burns are dynamic injuries with a central zone of necrosis surrounded by a zone of ischemia. Conversion of this ischemic zone to full necrosis over the days following injury is due in part to highly reactive oxygen radicals. Curcumin is a component of the Oriental spice turmeric that has been shown to have antioxidant and antiapoptotic properties. The authors hypothesized that treatment of burns with curcumin would reduce the conversion of the ischemic zone to full necrosis. Methods This was a randomized controlled experiment. Twenty Sprague‐Dawley rats were used. Two burns were created on each animal's dorsum using a brass comb with four rectangular prongs preheated in boiling water and applied for 30 seconds, resulting in four rectangular 10 × 20–mm full‐thickness burns separated by three 5 × 20–mm unburned interspaces (zone of ischemia). Animals were randomized to curcumin or vehicle by oral gavage 30 minutes before injury and at 24, 48, and 72 hours after injury. Wounds were observed at one, two, and three days after injury for visual evidence of necrosis in the unburned interspaces. Full‐thickness biopsy specimens from the interspaces were evaluated with hematoxylin and eosin staining seven days after injury for evidence of necrosis. The percentage of interspaces that progressed to necrosis was compared with chi‐square tests. Results Forty comb burns with 120 unburned interspaces were created, evenly distributed between curcumin and vehicle alone. The percentage of interspaces that progressed to full‐thickness necrosis at one, two, three, and seven days after injury in the curcumin and vehicle groups were 30% versus 63% (p = 0.003), 30% versus 70% (p < 0.001), 63% versus 95% (p = 0.02), and 63% versus 95% (p = 0.02), respectively. Conclusions Pretreatment of rats with oral curcumin followed by once‐daily oral treatment for three days reduced the percentage of unburned skin interspaces that progressed to full necrosis. 相似文献
3.
Genotype determining low catechol-O-methyltransferase activity as a risk factor for obsessive-compulsive disorder
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Maria Karayiorgou Margaret Altemus Brandi L. Galke David Goldman Dennis L. Murphy Jurg Ott Joseph A. Gogos 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(9):4572-4575
In the present study, we address the role of the gene for catechol-O-methyltransferase (COMT), a key modulator of dopaminergic and noradrenergic neurotransmission, in the genetic predisposition to obsessive-compulsive disorder (OCD). We show that a common functional allele of this gene, which results in a 3- to 4-fold reduction in enzyme activity, is significantly associated in a recessive manner with susceptibility to OCD, particularly in males. This association is further supported by psychiatric evaluation of patients who carry microdeletions encompassing the comt gene. The mechanism underlying this sex-selective association remains to be defined and may include a sexual dimorphism in COMT activity, although close linkage with a nearby disease susceptibility locus cannot be excluded at this point. 相似文献
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Trevor McClain Griffitts Chad Patrick Collins Patrick Charles Collins 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(5):e81-e84
OBJECTIVE: This article examines the success of mini-dental implants (MDI'S) by assessing four subjective measures of patient satisfaction for MDI's in the edentulous maxilla and mandible: comfort, retention, chewing ability and speaking ability. Success rates, surgical techniques, and financial advantages of the MDI's are reviewed. STUDY DESIGN: Thirty consecutive patients received four MDI's between the mental foramen of the mandible from 9/18/2003 to 10/22/2004. Questionnaires were sent to all thirty patients an average of 5 months postoperatively. The patients ranked comfort, retention, chewing ability, and speaking ability from 1 to 10 (1=poor and 10=excellent). RESULTS: A total of 116 MDI's were placed in 13 months and 113 remain stable for a 97.4% implant success rate. Pre-operatively patients rated their retention at 1.7+/-0.42 and post-operatively at 9.6+/-0.37, for a difference of 7.9 (p=3.6-19). Comfort was the next greatest improvement, with a pre-operative rating of 2.2+/-0.63 and a post-operative rating of 9.4+/-0.45, for a difference of 7.2 (p=3.5-15). Chewing ability also improved, with a difference of 7.0 (p=2.9e-16). In the final category of speaking ability, the pre-operative to post-operative difference was 3.2 (p=1.1e-5). CONCLUSION: MDI's are a highly successful implant option for patients with poor tolerance to maxillary and mandibular prosthesis. The implants are relatively affordable and overall patient satisfaction is excellent. 相似文献
7.
Alberto Falchetti Marco Di Stefano Francesca Marini Francesca Del Monte Carmelo Mavilia Debora Strigoli Maria L De Feo Giovan Isaia Laura Masi Antonietta Amedei Federica Cioppi Valentina Ghinoi Susanna Maddali Bongi Giuseppina Di Fede Carmela Sferrazza Giovan B Rini Daniela Melchiorre Marco Matucci-Cerinic Maria L Brandi 《Journal of bone and mineral research》2004,19(6):1013-1017
PDB is genetically heterogeneous. Mutations of the sequestosome1 gene have been reported in sporadic and familial forms of Paget's in patients of French Canadian and British descent. Mutational analyses in different ethnic groups are needed to accurately investigate hereditary diseases. We describe two novel mutations of sequestosome1 in 62 Italian sporadic patients, confirming the role of the encoded protein in this disorder. INTRODUCTION: Paget's disease of bone (PDB) is a relatively common disease of bone metabolism reported to affect up to 3% of whites over 55 years of age. The disorder is genetically heterogeneous, and at present, there is scientific evidence that at least eight different human chromosomal loci are correlated with its pathogenesis. Mutations of the sequestosome1 (SQSTM1) gene were identified as responsible for most of the sporadic and familial forms of Paget in patients of French Canadian and British descent. Such mutations were located at exon 7 and 8 levels, encoding for the ubiquitin protein-binding domain (UBA) and representing a mutational hot spot area. MATERIALS AND METHODS: To verify the involvement of this gene in Italian subjects affected by PDB, we performed mutational analysis in 62 sporadic PDB cases. RESULTS: We described three different mutations at exon 8 level: P392L, already described in the French Canadian population and families predominantly of British descendent, and two novel mutations consisting of the amino acid substitutions M404V and G425R. No significant differences in the clinical history of PDB have been observed in patients with SQSTM1 mutations in respect to those without. CONCLUSIONS: Even though our findings suggest a minor involvement of the SQSTM1 gene in the pathogenesis of sporadic Italian Paget's cases, the identification of different significant mutations within the SQSTM1 gene in unrelated, but clinically similar individuals, offers extremely convincing evidence for a causal relationship between this gene and PDB. Longitudinal studies are needed to assess the penetrance of genotype/phenotype correlations. Our findings confirm the evidence of a clustered mutation area at this level in this disorder. 相似文献
8.
Altered gastric emptying in the head-injured patient: relationship to feeding intolerance 总被引:12,自引:0,他引:12
L Ott B Young R Phillips C McClain L Adams R Dempsey P Tibbs U Y Ryo 《Journal of neurosurgery》1991,74(5):738-742
Most patients with moderate to severe head injury initially do not tolerate enteral feedings postinjury. This intolerance is more prolonged than that found in patients suffering other types of trauma. The authors prospectively evaluated 12 patients with moderate to severe head injury (Glasgow Coma Scale score between 4 and 10) throughout their hospitalization for liquid gastric emptying as a possible mechanism for intolerance to enteral feeding. During Week 1, the majority of patients displayed a delay in gastric emptying. Patients also displayed an abnormal biphasic response (gastric emptying faster than normal during the early stage but prolonged later). By Week 2, many patients still had delayed and abnormal biphasic responses to gastric emptying. By Week 3, an improvement was observed with the majority of patients exhibiting rapid gastric emptying, but delays and abnormal biphasic responses were still seen. Patients who initially had rapid or normal gastric emptying tolerated full-strength full-rate feedings significantly earlier compared with those who experienced delayed gastric emptying (8.5 +/- 0.5 days vs. 13.7 +/- 3.2 days, p less than 0.001). All patients tolerated full-strength full-rate feedings by Day 16 postinjury (range 7 to 16 days) except the two patients who displayed delayed gastric emptying for prolonged periods of time (mean 25 days). This is the first study to longitudinally evaluate gastric emptying following head injury. The authors suggest that patients with moderate to severe head injury often experience alterations in gastric emptying which may affect their ability to tolerate enteral feedings. 相似文献
9.
Ben F. Brammell J. Scott McClain James T. Oris David J. Price Wesley J. Birge Adria A. Elskus 《Archives of environmental contamination and toxicology》2010,58(3):772-782
It has become increasingly apparent that resident fish can develop resistance to chemicals in their environment, thus compromising
their usefulness as sentinels of site-specific pollution. By using a stream system whose resident fish appear to have developed
pollutant resistance (Brammell et al., Mar Environ Res 58:251–255, 2005), we tested the hypothesis that the pollutant-inducible biomarker, cytochrome P4501A (CYP1A), as measured in field-caged
juvenile rainbow trout (Oncorhynchus mykiss), would reflect relative pollution differences between reference and polychlorinated biphenyl (PCB)-contaminated sites. Trout
were caged in the Town Branch/Mud River system (Logan County, KY), a stream system undergoing remediation for PCBs. Fish were
held in remediated (Town Branch), unremeditated (Mud River), and reference sites for 2 weeks during spring 2002. At the end
of this period, gill and hepatic CYP1A expression were measured. To evaluate the relative PCB exposure of caged trout and
provide a reference point against which to calibrate CYP1A response, PCB levels were quantified in sediments from each site.
Hepatic CYP1A expression in caged trout clearly detected the presence of PCBs in the Town Branch/Mud River stream system.
Sediment PCB levels and hepatic CYP1A expression in caged trout produced identical pollution rankings for the study sites.
Gill CYP1A expression, although suggestive of site differences, was not statistically different among sites. Unlike resident
fish, which failed to show site differences in hepatic CYP1A expression in this waterway (Brammell et al. 2005), caged fish proved to be a sensitive discriminator of relative PCB contamination in this system. In summary, we determined
that CYP1A expression in caged fish reflected relative in situ pollutant exposure. The exposure paradigm confirmed that 2 weeks
was a sufficient caging period for evaluating CYP1A response in this species at these temperatures (13–19°C). In addition,
these studies demonstrate that tissue-specific CYP1A expression can provide insights into likely routes of exposure. We conclude
that CYP1A expression in caged trout is a reliable and inexpensive first-pass determination of relative environmental pollutant
exposure and bioavailability in aqueous systems. 相似文献
10.
Robert W. Mendicino DPM FACFAS Alan R. Catanzariti DPM FACFAS Karl R. Saltrick DPM FACFAS Michael F. Dombek DPM Brandon L. Tullis DPM Trenton K. Statler DPM Brandi M. Johnson DPM 《The Journal of foot and ankle surgery》2004,43(2):82-86
Nineteen patients (20 feet) with severe hindfoot and ankle deformity underwent tibiotalocalcaneal fusion with a retrograde locked intramedullary nail as a limb-salvage procedure. The purpose of this study was to compare the complication rates of this procedure in diabetic versus nondiabetic patients. There were 8 men and 11 women with preoperative diagnoses including Charcot neuroarthropathy, primary osteoarthritis, rheumatoid arthritis, equinocavovarus, posttraumatic osteoarthritis, gouty arthritis, and ankle malunion. Ten of 20 procedures were performed in patients with diabetes. The average patient age was 56 years, and the average postoperative follow-up was 19.8 months. Nineteen of 20 ankles (95%) achieved successful fusion with an average time of 4.1 months. Four patients (21%) required either a fracture brace or an ankle foot orthosis at final follow-up. Five patients (25%) had major complications and 11 patients had minor complications. Major complications included osteomyelitis (n = 2), Charcot arthropathy (n = 2), failure of fixation (n =1), soft-tissue necrosis (n = 1), cardiac arrest (n = 1), cerebral vascular accident (n = 1), and fatal pulmonary embolus (n = 1). All patients with major complications were diabetic, and 14 of 20 combined major and minor complications occurred in patients with diabetes. The complication rate was found to be high in diabetic patients with end-stage deformity undergoing a limb salvage 相似文献