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991.
Fine-needle aspiration cytology (FNAC) is routinely employed for the preoperative diagnosis of salivary gland lesions. Although most cases show morphologic features characteristic of specific entities, some lesions can be diagnostically challenging. We report two parotid aspirates, initially diagnosed as pleomorphic adenoma on FNA. The patients, a 33-yr-old white man, and a 24-yr-old white woman, presented with indurated lesions arising in the parotid gland region. The aspirates from both patients were markedly hypercellular. Smears showed a mixture of spindle cells with a well-demarcated cytoplasm showing occasional long cytoplasmic process; and cells with abundant cytoplasm with round to oval eccentric nuclei, giving the impression of plasmacytoid cells of pleomorphic adenoma. The nuclear chromatin was evenly distributed and finely granular with one or two occasional small nucleoli. Intermingled with the tumor cells were scattered neutrophils, eosinophils, and macrophages. Aggregates of spindle cells were also seen embedded in a mucoid background with occasional small tufts of a fibrillar mucoid stroma. These fibrillar tufts were magenta red in the Diff-Quik stain, giving the impression of matrix of pleomorphic adenoma. Both cases were later diagnosed on histologic examination as nodular fasciitis. Nodular fasciitis should be considered in the differential diagnosis of a mass arising in association with the parotid gland. 相似文献
992.
Association between apolipoprotein E (apoE) gene polymorphism and lipid levels was studied in 164 nondiabetic first-degree relatives of persons with diabetes and 962 nondiabetic persons with no family history of diabetes. Sex-specific genotypic distribution of apoE polymorphism did not differ between persons with and without a family history of diabetes. In first-degree relatives, lipid levels did not differ among persons with apoE2 (E2/2, E2/3), apoE3/3, and apoE4 (E4/4, E3/4) after adjusting for age, waist circumference, smoking, and alcohol and estrogen use. In persons without a family history of diabetes, both men (p<0.01) and women (p<0.001) with apoE2 showed lower levels of total and low density lipoprotein cholesterol compared with persons with apoE3/3 and apoE4. In women with a family history of diabetes, persons with apoE4 had larger waist circumference (p<0.05). ApoE2 allele is associated with more favorable levels of total and low density lipoprotein cholesterol in men and women without a family history of diabetes. ApoE4 allele is associated with obesity independent of dyslipidemia in women but not men with a family history of diabetes. ApoE polymorphism is not associated with lipids in men or women with a family history of diabetes. 相似文献
993.
Rodríguez-Iturbe B Sindhu RK Quiroz Y Vaziri ND 《Antioxidants & redox signaling》2005,7(9-10):1269-1274
Chronic exposure to low doses of lead results in generation of reactive oxygen species, reduced nitric oxide availability, and arterial hypertension. The present studies were done to define if other conditions associated with oxidative stress, such as renal interstitial inflammation, nuclear factor-kappaB (NF-kappaB) activation, and cells expressing angiotensin II, are, in fact, features of low-dose lead exposure. Male Sprague-Dawley rats were randomly assigned to the lead group (n = 8) or the control group (n = 9). The lead group received 100 ppm lead acetate in the drinking water for 14 weeks. At the end of this period of time, rats were killed under general anesthesia, and the kidneys were harvested for studies. The lead-exposed group presented focal tubulointerstitial damage and highly significant increments in nitrotyrosine immune staining, lymphocyte and macrophage infiltration, angiotensin II-positive cells, and intranuclear positive staining for the p65 DNA-binding subunit of NF-kappaB in tubulointerstitial cells. Tubulointerstitial inflammation, cells expressing angiotensin II, and NF-kappaB activation are consequences of a 3-month low-dose exposure to lead and likely play a role in the development of hypertension and chronic lead nephropathy. 相似文献
994.
Melandri Vlok Anne Marie E. Snoddy Niranjan Ramesh Benjamin J. Wheeler Vivien G. Standen Bernardo T. Arriaza 《American journal of human biology》2023,35(2):e23819
For more than two centuries, lack of sunlight has been understood to cause vitamin D deficiency and documented as a primary cause of rickets. As such, evidence of rickets in the archeological record has been used as a proxy for vitamin D status in past individuals and populations. In the last decade, a clinical global consensus has emerged wherein it is recognized that dietary calcium deficiency also plays a role in the manifestation of rickets and classic skeletal deformities may not form if dietary calcium is normal even if vitamin D is deficient. This disease is now clinically called “nutritional rickets” to reflect the fact that rickets can take calcium deficiency-predominant or vitamin D deficiency-predominant forms. However, there are currently no paleopathological studies wherein dietary calcium deficiency is critically considered a primary etiology of the disease. We review here the interplay of calcium, vitamin D, and phosphorous in bone homeostasis, examine the role of dietary calcium in human health, and critically explore the clinical literature on calcium deficiency-predominant rickets. Finally, we report a case of rickets from the late Formative Period (~2500–1500 years ago) of the Atacama Desert and argue the disease in this infant is likely an example of calcium deficiency-predominant rickets. We conclude that most archeological cases of rickets are the result of multiple micronutrient deficiencies that compound to manifest in macroscopic skeletal lesions. For clinicians, these factors are important for implementing best treatment practice, and for paleopathologists they are necessary for appropriate interpretation of health in past communities. 相似文献
995.
996.
Bernardo V Ramos MP Plapler H De Figueiredo LF Nader HB Anção MS Von Dietrich CP Sigulem D 《International journal of medical informatics》2004,73(9-10):731-742
In order to increase the number of practical and discussion classes offered to students in the traditional-curriculum scenario, while decreasing the lecture-based ones and to create an online community to share knowledge on surgery, we developed and assessed the first online course for undergraduate medical students on experimental surgery at the Federal University of Sao Paulo-UNIFESP, Brazil. The purposes of the present study are: describe and discuss the process and the lessons learned involved in developing an undergraduate web-based course and analyze the students' attitude towards this educational environment. A group of medical students was taught online during 5 weeks on the theory of experimental surgery through video quizzes, required readings, collaborative activities using discussion board and asynchronous communication. The students' knowledge gain, their web session variables and the results of the course evaluation were used to support our study. The students have significantly improved their knowledge on experimental surgery after the course. Among factors in the online course that could possibly have contributed to this gain, the interactive activities (video quizzes), key element in our online material, seemed to be promising for candidates. The evaluation results demonstrated high levels of course functionality, effectiveness of its online content and acceptance among medical students. This study indicated that a web-based course for undergraduate students may be successfully developed and implemented in medical settings and the students seem to be quite supportive. We encourage undergraduate medical learning strategies involving the Web. 相似文献
997.
Ishar Dalmau Bente Finsen Niels Tnder Jens Zimmer Berta Gonzlez Bernardo Castellano 《The Journal of comparative neurology》1997,377(1):70-84
The distribution and appearance of microglial cell precursors in the prenatal hippocampus were examined in embryonic day 14 (E14) to E21 rats by nucleoside diphosphatase histochemistry. For comparison, the differentiation of astroglial cells was analyzed from E17 by vimentin and glial fibrillary acidic protein immunohistochemistry. Based on morphologic features, nucleoside diphosphatase-positive microglial cell precursors were classified as ameboid microglial cells and primitive ramified microglial cells. Ameboid microglia were present in the hippocampal primordium on E14. As the hippocampus developed, however, ameboid microglia gradually transformed into primitive ramified microglia, first recognized at E19. Microglial cell precursors, often related to nucleoside diphosphatase-labeled blood vessels, were particularly observed next to the pial surface on days E14 and E17 and in the highly vascularized area around the hippocampal fissure from E19. Within the brain parenchyma, the microglial cell precursors tended to be located within the differentiating cell and neuropil layers rather than in the germinative zones. The late developing dentate gyrus remained almost devoid of microglial cell precursors before birth. Vimentin-positive astroglial processes with radial orientation were observed throughout the hippocampal subregions from E17. In contrast, glial fibrillary acidic protein-positive, radial processes were barely discernible in the fimbria and the dentate gyrus before E19. The results are discussed in relation to the possible interactive role of microglial cells in central nervous tissue development and histogenesis. Regarding the origin of hippocampal microglial cell precursors, the present observations support the view that these cells may well originate from different mesodermal sources depending on time and localization. J. Comp. Neurol. 377:70-84, 1997. © 1997 Wiley-Liss, Inc. 相似文献
998.
HIV-gp120 affects the functional activity of oligodendrocytes and their susceptibility to complement
Antonietta Bernardo Cristina Agresti Giulio Levi 《Journal of neuroscience research》1997,50(6):946-957
The aim of this study was to assess whether the HIV protein gp120 can induce direct or/and indirect damage to oligodendrocytes (OL). Using highly purified cultures of rat OL, we report that gp120 binds to OL and induces functional alterations in these cells. Indeed, the percentage of cells expressing myelin basic protein (MBP) and the levels of all four MBP isoforms were substantially reduced after a 3-day treatment with 10 nM gp120. As gp120 depressed the ability of OL to reduce the tetrazolium salt MTT (a sign of mitochondrial impairment), the alteration of MBP production may be a consequence of decreased metabolic activity. The above effects were accompanied by a small increase in the number of apoptotic nuclei (from 4.3% in controls to 17.6% in cells treated for 3 days with gp120). As complement can lyse OL and gp120 is known to activate complement, we also studied the interaction between these two factors using OL cultures. The viral protein potentiated (by about 25%) the lytic effect of complement, when administered to the cultures 5 hr after complement, and depressed it (by about 30–40%), when added 5 hr before complement. Heat denaturation and anti-gp120 antibodies prevented the direct effect of gp120 on OL, but did not influence the interactions between gp120 and complement. Some gp120 non glycosylated peptides (V3 loop, 254-274 and 415-435 peptides) mimicked the ability of gp120 to antagonize the lytic effect of complement, but not that of potentiating complement lytic activity. In conclusion, our study indicates that gp120 can alter OL functional activity directly and can interfere with OL susceptibility to complement mediated lysis. J. Neurosci. Res. 50:946–957, 1997. © 1997 Wiley-Liss, Inc. 相似文献
999.
Mokhtar Mahmoud Jozef Kraxner Hana Kakov Miroslava Hujov Si Chen Duan Galusek Enrico Bernardo 《Materials》2022,15(3)
Fiber glass waste (FGW) was subjected to alkali activation in an aqueous solution with different concentrations of sodium/potassium hydroxide. The activated materials were fed into a methane–oxygen flame with a temperature of around 1600 °C. X-ray diffraction analysis confirmed the formation of several hydrated compounds, which decomposed upon flame synthesis, leading to porous glass microspheres (PGMs). Pore formation was favored by using highly concentrated activating alkali solutions. The highest homogeneity and yield of PGMs corresponded to the activation with 9 M KOH aqueous solution. 相似文献
1000.
Giulia Menculini Umberto Albert Valeria Bianchini Claudia Carmassi Giuseppe Carr Francesca Cirulli Bernardo DellOsso Michele Fabrazzo Francesco Perris Gaia Sampogna Maria Giulia Nanni Maurizio Pompili Gabriele Sani Umberto Volpe Alfonso Tortorella 《European psychiatry》2021,64(1)
BackgroundWhen facing a traumatic event, some people may experience positive changes, defined as posttraumatic growth (PTG).MethodsUnderstanding the possible positive consequences of the pandemic on the individual level is crucial for the development of supportive psychosocial interventions. The present paper aims to: 1) evaluate the levels of PTG in the general population; 2) to identify predictors of each dimension of post-traumatic growth.ResultsThe majority of the sample (67%, N = 13,889) did not report any significant improvement in any domain of PTG. Participants reported the highest levels of growth in the dimension of “appreciation of life” (2.3 ± 1.4), while the lowest level was found in the “spiritual change” (1.2 ± 1.2). Female participants reported a slightly higher level of PTG in areas of personal strength (p < .002) and appreciation for life (p < .007) compared to male participants, while no significant association was found with age. At the multivariate regression models, weighted for the propensity score, only the initial week of lockdown (between 9-15 April) had a negative impact on the dimension of “relating to others” (B = −.107, 95% CI = −.181 to −.032, p < .005), while over time no other effects were found. The duration of exposure to lockdown measures did not influence the other dimensions of PTG.ConclusionsThe assessment of the levels of PTG is of great importance for the development of ad hoc supportive psychosocial interventions. From a public health perspective, the identification of protective factors is crucial for developing ad-hoc tailored interventions and for preventing the development of full-blown mental disorders in large scale. 相似文献