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101.
Emerson V. A. Lima Mariana Modesto D. A. Lima Mauricio Pedreira Paixão Hélio Amante Miot 《BMC dermatology》2017,17(1):14
Background
Melasma is a common chronic and relapsing acquired dyschromia. Skin microneedling was reported resulting sustained long-term improvement of recalcitrant melasma, however, the exact mechanism that promotes this skin lightening is not known. This study aimed to investigate clinical and histologic alterations promoted by skin microneedling in facial melasma.Methods
Open pilot trial including six women with facial refractory melasma submitted to two sessions of microneedling (1.5 mm) each 30 days followed by daily triple combination and broad-spectrum sunscreen. Comparison of pretreatment (T0) and 15 days after last microneedling procedure (T45) was made by standardized pictures, skin colorimetry, MASI, MELASQoL and histological parameters (haematoxylin-eosin, picrosirius-red, periodic acid Schiff and Fontana-Masson staining).Results
The age of the subjects varied from 34 to 46 years-old, the phototypes were III and IV (Fitzpatrick), and age of melasma onset was 20 to 38 years. Improvement of melasma was perceived in all subjects. There was a significant reduction of MASI score (?70%), MELASQoL (?55%) and increase in L* (+13%) colorimetric value (p <?0.03). All cases evidenced epithelium thickening, decrease in melanin pigmentation and densification of upper dermis collagen (p =?0.03). Patients were followed by 6 months under broad-spectrum sunscreen and triple combination without relapse.Conclusion
In addition to classic treatment (broad-spectrum sunscreen and triple combination), skin microneedling promoted clinical and histological improvement of refractory facial melasma.102.
Gene-centric metagenomics of the fiber-adherent bovine rumen microbiome reveals forage specific glycoside hydrolases 总被引:7,自引:0,他引:7
Jennifer M. Brulc Dionysios A. Antonopoulos Margret E. Berg Miller Melissa K. Wilson Anthony C. Yannarell Elizabeth A. Dinsdale Robert E. Edwards Edward D. Frank Joanne B. Emerson Pirjo Wacklin Pedro M. Coutinho Bernard Henrissat Karen E. Nelson Bryan A. White 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(6):1948-1953
The complex microbiome of the rumen functions as an effective system for the conversion of plant cell wall biomass to microbial protein, short chain fatty acids, and gases. As such, it provides a unique genetic resource for plant cell wall degrading microbial enzymes that could be used in the production of biofuels. The rumen and gastrointestinal tract harbor a dense and complex microbiome. To gain a greater understanding of the ecology and metabolic potential of this microbiome, we used comparative metagenomics (phylotype analysis and SEED subsystems-based annotations) to examine randomly sampled pyrosequence data from 3 fiber-adherent microbiomes and 1 pooled liquid sample (a mixture of the liquid microbiome fractions from the same bovine rumens). Even though the 3 animals were fed the same diet, the community structure, predicted phylotype, and metabolic potentials in the rumen were markedly different with respect to nutrient utilization. A comparison of the glycoside hydrolase and cellulosome functional genes revealed that in the rumen microbiome, initial colonization of fiber appears to be by organisms possessing enzymes that attack the easily available side chains of complex plant polysaccharides and not the more recalcitrant main chains, especially cellulose. Furthermore, when compared with the termite hindgut microbiome, there are fundamental differences in the glycoside hydrolase content that appear to be diet driven for either the bovine rumen (forages and legumes) or the termite hindgut (wood). 相似文献
103.
CP Halvorsen SL Bilock C Pilo S-E Sonesson M Norman 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(9):1468-1474
Aim: To perform a 10-year follow up of cardiac structure and function after twin-to-twin transfusion syndrome (TTTS) – a severe foetal circulatory complication associated with myocardial hypertrophy in the recipient twin.
Methods: Cardiac dimensions, systolic and diastolic function as assessed by echocardiography including flow and tissue Doppler velocimetry in 22 healthy survivors of TTTS with a mean age of 9.6 (7.2–11.8) years.
Results: The donor and recipient twin did not show any differences in end-diastolic ventricular size, interventricular septum thickness, diameter of right ventricular outflow tract, cardiac valves, coronary arteries or in systolic blood flow velocities. However, compared with the donors, the recipients had significantly lower E/A ratios because of lower E-waves in both mitral (−0.15 ± 0.10, p < 0.01) and tricuspid (−0.09 ± 0.07, p < 0.01) valves, indicating reduced early diastolic ventricular fillings compared with donors.
Conclusion: At school age, twins surviving TTTS had a cardiac structure and function within normal range. There were no differences in heart structure or systolic ventricular function between twins but, compared with the donor twin, we found a reduced early diastolic function in the recipient. 相似文献
Methods: Cardiac dimensions, systolic and diastolic function as assessed by echocardiography including flow and tissue Doppler velocimetry in 22 healthy survivors of TTTS with a mean age of 9.6 (7.2–11.8) years.
Results: The donor and recipient twin did not show any differences in end-diastolic ventricular size, interventricular septum thickness, diameter of right ventricular outflow tract, cardiac valves, coronary arteries or in systolic blood flow velocities. However, compared with the donors, the recipients had significantly lower E/A ratios because of lower E-waves in both mitral (−0.15 ± 0.10, p < 0.01) and tricuspid (−0.09 ± 0.07, p < 0.01) valves, indicating reduced early diastolic ventricular fillings compared with donors.
Conclusion: At school age, twins surviving TTTS had a cardiac structure and function within normal range. There were no differences in heart structure or systolic ventricular function between twins but, compared with the donor twin, we found a reduced early diastolic function in the recipient. 相似文献
104.
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107.
ObjectiveTo investigate the potentials of the root bark of Annona (A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.MethodsThe methanol extract (ME) of the root bark of A. senegalensis was studied in mice using pentylenetetrazole (PTZ) induced convulsions, phenobarbitone induced sleeping time and motor coordination test on rota-rod performance. Acute toxicity and lethality (LD50) test as well as phytochemical analysis were also carried out.ResultsThe extract (200, 400, 800 mg/kg) exhibited a non-dose dependent significant (P <0.05) delay in the onset of both tonic and clonic phases of seizure induced by PTZ (60 mg/kg, s.c.) as well as offered a 100% protection (200 mg/kg) in mice from PTZ induced seizures. The extract significantly (P <0.05) decreased the latency and increased the duration of phenobarbitone induced sleeping time. At 200 mg/kg, the extract exhibited a significant (P <0.05) motor incoordination. The acute toxicity test revealed an oral LD50 of 1 296 mg/kg, while the phytochemical studies showed the presence of alkaloids, resins, glycosides, carbohydrate, reducing sugar, flavonoids, terpenoids, saponins and tannins.ConclusionThe extract of A. senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects. 相似文献
108.
Laboratory utilization by clinician specialty groups serving outpatients was monitored before and after requisition redesign. Requisition changes were designed to address compliance and utilization issues and included implementation of test groupings and cascades or ordering algorithms. Data collected included the number of selected tests and test sets ordered during both time intervals and the number of patient office visits. Selected tests for monitoring included CBC counts, metabolic panels, thyroid function tests, hepatic function tests, urine analysis, and send-out testing. Statistical significance was measured using Poisson rates for test ordering. The composite effect was a significant decrease in the overall number of tests ordered per outpatient visit for most specialties, with a shift in ordering practices from panels to individual tests. Utilization rates by specialty groups were characterized by average number of laboratory tests ordered per patient visit. 相似文献
109.
Marcos Emerson Pinheiro Junqueira Lidiane Zito Grund Noêmia M Orii Tania Cristina Saraiva Carlos Alberto de Magalh?es Lopes Carla Lima M?nica Lopes-Ferreira 《Toxicon》2007,49(7):909-919
Cathorops spixii is one of the most abundant venomous fish of the southeastern coast of the State of S?o Paulo, and consequently causes a great part of the accidents seen there. The accidents affect mainly fishermen, swimmers and tourists and are characterized by punctiform or wide wounds, erythema, edema, pain, sudoresis, indisposition, fever, nausea, vomiting and secondary infection. The objective of this work was to characterize the inflammatory response induced in mice by both venoms (mucus and sting) of the catfish C. spixii. Our results demonstrated that both venoms induced a great number of rolling and adherent leukocytes in the post-capillary venules of cremaster muscle of mice, and an increase in the vascular permeability in peritoneal cavity. Mucus induced the recruitment of neutrophils immediately after injection followed later by macrophage infiltration. In contrast, the cellular infiltration elicited by sting venom was rapidly resolved. The peritonitis reaction provoked by venoms was characterized by cytokine (IL-6), chemokines (MCP-1 and KC) or lipid mediator (LTB4) production in the peritoneal cavity. The macrophages from 7-day mucus venom-induced exudates upon in vitro mucus venom stimulation, expressed CD11c x MHC class II and release bioactive IL-12p70. On the other hand, sting venom-elicited peritoneal macrophages lost the ability to differentiate into dendritic cells, following re-stimulation in vitro with sting venom, they do not express CD11c, nor do they exhibit sufficient levels of MHC class II. In conclusion, both types of venoms (mucus or sting) promote inflammatory reaction with different profiles, and the inflammatory reaction induced by the first was characterized by antigen persistence in peritoneal cavity that allowed the activation of phagocytic cells with capacity of antigenic presentation. 相似文献
110.