RESUMO
During October 1971, four cesium beam atomic clocks were flown on regularly scheduled commercial jet flights around the world twice, once eastward and once westward, to test Einstein's theory of relativity with macroscopic clocks. From the actual flight paths of each trip, the theory predicts that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40 +/- 23 nanoseconds during the eastward trip, and should have gained 275 +/- 21 nanoseconds during the westward trip. The observed time differences are presented in the report that follows this one.
RESUMO
Four cesium beam clocks flown around the world on commercial jet flights during October 1971, once eastward and once westward, recorded directionally dependent time differences which are in good agreement with predictions of conventional relativity theory. Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59 +/- 10 nanoseconds during the eastward trip and gained 273 +/- 7 nanoseconds during the westward trip, where the errors are the corresponding standard deviations. These results provide an unambiguous empirical resolution of the famous clock "paradox" with macroscopic clocks.
RESUMO
We report about a rare case of malakoplakia in a female urethral diverticulum. A 25-year-old patient with a long history of recurrent urinary tract infections and a plum-sized, painful swelling on the vaginal roof presented for operative treatment. In the anamnesis the patient reported about two spontaneous perforations, emptying several millilitres of pus each time. After total operative excision using a vaginal approach the histology showed malakoplakia in a urethral diverticulum. We found the typical intracytoplasmatic "Michaelis-Gutmann bodies" as well as "von Hansemann cells". Postoperatively we excluded an underlying tumour disease or a chronic infection. The further urological diagnostics (cystoscopy and MRI) were without any pathological findings. In patients with atypical cystic tumours of the urogenital tract, especially with an immune deficiency, malakoplakia should be taken in consideration. The preferred therapy is surgical management followed by long-term antibiosis as well as a close follow-up as recurrences are frequent.
Assuntos
Divertículo , Malacoplasia , Doenças Uretrais , Adulto , Antibacterianos/uso terapêutico , Cistoscopia , Divertículo/complicações , Divertículo/diagnóstico , Divertículo/diagnóstico por imagem , Divertículo/patologia , Divertículo/cirurgia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Malacoplasia/diagnóstico , Malacoplasia/patologia , Cuidados Pós-Operatórios , Radiografia , Recidiva , Fatores de Tempo , Uretra/patologia , Doenças Uretrais/complicações , Doenças Uretrais/diagnóstico , Doenças Uretrais/diagnóstico por imagem , Doenças Uretrais/patologia , Infecções Urinárias/complicaçõesRESUMO
Interleukin-8 (IL-8) is a cytokine that is thought to promote melanoma tumour progression. We evaluated and adapted a non-radioactive, reverse transcriptase-polymerase chain reaction method for semiquantitative analysis of IL-8 mRNA expression. Using this technique we studied the regulation of IL-8 levels in the melanoma cell line Colo 38. Seeding of melanoma cells into culture dishes resulted in a significant increase of IL-8 expression, which could be attributed to adherence. A pronounced increase of IL-8 mRNA expression and protein production was induced by tumour necrosis factor-alpha (TNF alpha). Interferon-gamma (IFN gamma) partially inhibited TNF alpha-induced IL-8 secretion, whereas no influence on IL-8 mRNA levels was detected. The inhibitory affect of IFN gamma on melanoma cells is in contrast to its stimulatory effect on melanocytes.