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1.
Intraoperative penile tumescence during endoscopic surgery is a troublesome complication that often is refractory to recommended methods of management. We report a new approach of pharmacological management with intracorporeal penile injections of phenylephrine (total dose of 0.1 mg.), which was successful in 3 successive patients. This approach is prompt, safe and reproducible, and it provides sustained resolution of erection without systemic side effects. It is concluded that local intracorporeal penile administration of this sympathomimetic agent appears to be a potent new tool in the armamentarium of the endoscopic surgeon dealing with this frustrating clinical situation, which merits further clinical trial. 相似文献
2.
Sinonasal surfactant protein A1, A2, and D gene expression in cystic fibrosis: a preliminary report. 总被引:1,自引:0,他引:1
Bradford A Woodworth Rachel Wood John E Baatz Rodney J Schlosser 《Otolaryngology--head and neck surgery》2007,137(1):34-38
OBJECTIVE: To measure alterations in SPA1, A2, and D gene expression in various forms of inflammatory chronic rhinosinusitis (CRS). STUDY DESIGN AND SETTING: Sinus mucosal biopsies were performed in patients with allergic fungal rhinosinusitis (AFS), CRS with nasal polyposis, cystic fibrosis (CF), and controls. SP mRNA was measured with quantitative polymerase chain reaction. RESULTS: Patients with CF (n = 4) showed significantly increased SPA1 (82-fold), SPA2 (100-fold), and SPD (47-fold) mRNA (P < 0.05) when compared with controls (n = 5). Patients with CRS with nasal polyposis (n = 5) also demonstrated elevated SPA1 (27-fold), SPA2 (13-fold), and SPD (13-fold). Patients with AFS (n = 7) had increased SPA1 (5-fold), SPA2 (9-fold), and SPD (17-fold), but were not statistically significant. CONCLUSION: SPA1, A2, and D are upregulated in various forms of CRS, but are significantly elevated in cystic fibrosis CRS. SIGNIFICANCE: Understanding the role of SPs in CRS will help develop novel treatment approaches for sinonasal pathoses. 相似文献
3.
Gene conversion is a likely cause of mutation in PKD1 总被引:3,自引:0,他引:3
Watnick TJ; Gandolph MA; Weber H; Neumann HP; Germino GG 《Human molecular genetics》1998,7(8):1239-1243
Approximately 70% of the gene responsible for the most common form of
autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in
several highly homologous copies located more proximally on chromosome 16.
We recently have described a novel technique for mutation detection in the
duplicated region of PKD1 that circumvents the difficulties posed by these
homologs. We have used this method to identify two patients with a nearly
identical cluster of base pair substitutions in exon 23. Since pseudogenes
are known to be reservoirs for mutation via gene conversion events for a
number of other diseases, we decided to test whether these sequence
differences in PKD1 could have arisen as a result of this mechanism. Using
changes in restriction digest patterns, we were able to show that these
sequence substitutions are also present in N23HA, a rodent-human somatic
cell hybrid that contains only the PKD1 homologs. Moreover, these changes
were also detected in total DNA from several affected and unaffected
individuals that did not harbor this mutation in their PKD1 gene copy. This
is the first example of gene conversion in PKD1 , and our findings
highlight the importance of using gene-specific reagents in defining PKD1
mutations.
相似文献
4.
Induction of squamous metaplasia in organ cultures of hamster trachea by naturally occurring and synthetic fibers 总被引:6,自引:0,他引:6
Asbestos exhibits many properties of classical tumor promoters. These characteristics include the ability to stimulate proliferation and inhibit normal differentiation of cells. In organ cultures of trachea, crocidolite and amosite asbestos stimulate squamous metaplasia, a pathological process in which a rapidly proliferating squamous epithelium replaces the normal epithelium. We hypothesized that the induction of metaplasia depends upon the fibrous nature of asbestos. Accordingly, several naturally occurring and synthetic fibrous materials and their nonfibrous analogues were assessed for their ability to induce metaplastic changes in tracheal mucosa of the Syrian hamster. Exposure to both crocidolite asbestos and fiberglass resulted in significant increases (p less than 0.05) in squamous metaplasia over a range of dosages (1.0, 4.0, 16.0 mg/ml). Attapulgite (palygorskite) and both "long-" and "short-" fiber preparations of chrysotile asbestos had similar but less marked effects. Nonfibrous analogues of each material (riebeckite, antigorite, and glass particles) failed to produce metaplasia. Asbestos, and fibrous materials in general, appear to stimulate squamous metaplasia because of their fibrous geometry. 相似文献
5.
6.
Licciardone JC Herron KM Marshall MA Woodworth RM 《The Journal of the American Osteopathic Association》2000,100(7):423-4, 427-31
Travel medicine practice in the United States has not been extensively studied. This study included 1078 consecutive patients who presented to a university-based travel medicine clinic from 1990 through 1994. Analyses of patient demographics, clinic attendance, itineraries, and vaccinations were conducted. Mean patient age (+/- SD) was 37.4 +/- 16.2 years; 626 (58.1%) of the patients were male. Travel duration was 103.1 +/- 242.3 days (median, 21 days), and lead time (defined as the time between clinic presentation and departure for the purpose of this study) was 23.8 +/- 26.5 days (median, 16 days). Destination was the strongest independent factor affecting vaccination practices. A lead time of 31 or more days was associated with significantly elevated odds ratios for all immunobiologicals except immune globulin. These findings underscore the need to educate the traveling public, healthcare providers, and the travel industry about the benefits of seeking medical consultation at least 1 month prior to international travel. 相似文献
7.
BACKGROUND: To evaluate debt and other factors that help formulate the career paths of future surgical and primary care physicians, a survey was undertaken. METHODS: Surgical specialty (SS) and primary care (PC) residents were surveyed regarding demographics, factors influencing choice of specialty, methods of financing education, debt characteristics, and outlooks regarding future earnings and practice characteristics. RESULTS: The clinical years of medical school and personalities of specialists and residents were important factors in career choices for both PC and SS. The length of residency, desirable lifestyle, and working hours were all more important to PC residents. Surgeons found intellectual challenge and procedure-based practice of greater importance. Although not highly regarded by either group, scholarship obligation and student loans had a significantly greater impact on specialty choice and practice plans for PC residents. At the completion of training, 55% of SS and 28% of PC residents anticipate owing more than $100,000. Debt was especially significant in specialty choice and practice plans for PC residents with debt over $100,000. CONCLUSION: Surgical residents are less concerned about personal sacrifices in their quest to become surgeons. It appears state funded scholarships are successful in attracting students to primary care. Both SS and PC residents have significant debt, although, SS residents have greater financial debt than primary care residents. However, the anticipation of indebtedness was a more significant factor in determination of career path for PC. 相似文献
8.
9.
l‐Methionine anti‐biofilm activity against Pseudomonas aeruginosa is enhanced by the cystic fibrosis transmembrane conductance regulator potentiator,ivacaftor 下载免费PDF全文
Calvin Mackey BS Christopher G. Weeks BS Jaime A. Peña Garcia BS Daniel Skinner BS Jessica W. Grayson MD Harrison S. Hill BS David K. Alexander Shaoyan Zhang PhD Bradford A. Woodworth MD 《International forum of allergy & rhinology》2018,8(5):577-583
Background
Biofilms may contribute to refractory chronic rhinosinusitis (CRS), as they lead to antibiotic resistance and failure of effective clinical treatment. l ‐Methionine is an amino acid with reported biofilm‐inhibiting properties. Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator with mild antimicrobial activity via inhibition of bacterial DNA gyrase and topoisomerase IV. The objective of this study was to evaluate whether co‐treatment with ivacaftor and l ‐methionine can reduce the formation of Pseudomonas aeruginosa biofilms.Methods
P aeruginosa (PAO‐1 strain) biofilms were studied in the presence of l ‐methionine and/or ivacaftor. For static biofilm assays, PAO‐1 was cultured in a 48‐well plate for 72 hours with stepwise combinations of these agents. Relative biofilm inhibitions were measured according to optical density of crystal violet stain at 590 nm. Live/dead assays (BacTiter‐Glo? assay, Promega) were imaged with laser scanning confocal microscopy. An agar diffusion test was used to confirm antibacterial effects of the drugs.Results
l ‐Methionine (0.5 μM) significantly reduced PAO‐1 biofilm mass (32.4 ± 18.0%; n = 4; p < 0.001) compared with controls. Low doses of ivacaftor alone (4, 8, and 12 μg/mL) had no effect on biofilm formation. When combined with ivacaftor (4 μg/mL), a synergistic anti‐biofilm effect was noted at 0.05 μM and 0.5 μM of l ‐methionine (two‐way analysis of variane, p = 0.0415) compared with corresponding concentrations of l ‐methionine alone.Conclusion
Ivacaftor enhanced the anti‐biofilm activity of l ‐methionine against the PAO‐1 strain of P aeruginosa. Further studies evaluating the efficacy of ivacaftor/l ‐methionine combinations for P aeruginosa sinusitis are planned.10.
BACKGROUND & AIMS: Shwachman syndrome is an inherited condition with multisystemic abnormalities, including exocrine pancreatic dysfunction. The aim of this study was to evaluate the occurrence and progression of features in a large cohort of patients. METHODS: Clinical records of 25 patients with Shwachman syndrome were reviewed. RESULTS: Mean birth weight (2.92 +/- 0.51 kg) was at the 25th percentile. However, by 6 months of age, mean heights and weights were less than the 5th percentile. After 6 months of age, growth velocity was normal. Severe fat maldigestion due to pancreatic insufficiency was present in early life (fecal fat, 26% +/- 17% of fat intake; age, < 2 years). Serial assessment of exocrine pancreatic function showed persistent deficits of enzyme secretion, but 45% of patients showed moderate age-related improvements leading to pancreatic sufficiency. Neutropenia was the most common hematologic abnormality (88%), but leukopenia, thrombocytopenia, and anemia were also frequently encountered. Patients with hypoplasia of all three bone marrow cellular lines (n = 11) had the worst prognosis; 5 patients died, 2 of sepsis and 3 of acute myelogenous leukemia. Other findings included hepatomegaly and/or abnormal liver function test results and skeletal abnormalities. CONCLUSIONS: A wide and varied spectrum of phenotypic abnormalities among patients with Shwachman syndrome is described. Pancreatic acinar dysfunction is an invariable abnormality. Patients with severe bone marrow involvement may have a guarded prognosis. (Gastroenterology 1996 Dec;111(6):1593-602) 相似文献