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There is an increased mortality associated with adrenal insufficiency despite glucocorticoid replacement therapy with a standardized mortality ratio greater than two. The cause of the increased mortality is yet to be definitively elucidated, but may be due to excess steroid exposure, or replacement regimens that are uncoupled from the normal physiological cortisol profile. Cortisol secretion follows an ultradian pattern which is not possible to reproduce using oral replacement. With the advent of new pumps, it is now possible to mimic the pulsatility of the adrenal glands. While the cognitive and emotional benefits of reproducing the ultradian rhythm are known, the presence of long‐term benefits is not yet clear. There is a dearth of evidence and high‐quality studies to underline our current understanding of the pathophysiology of adrenal insufficiency and replacement therapy. There is a particular lack of research comparing objective outcomes between patients receiving hydrocortisone replacement (either standard therapy or new sustained release preparations), prednisolone replacement and ultradian pumps. Direct comparative studies are now warranted to understand the optimal approach. 相似文献
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Ruth Addison Lauren Hill Lars Bode Bianca Robertson Biswa Choudhury David Young Charlotte Wright Clare Relton Ada L. Garcia David M. Tappin 《Maternal & child nutrition》2020,16(1)
The WHO recommends exclusive breastfeeding for 6 months, but despite interventions, breastfeeding rates remain stubbornly low. Financial voucher incentives have shown promise but require a biomarker for validation of intake. This study aimed to develop a simple biochemical assay of infant urine that would tell if an infant was receiving any breast milk to validate maternal report. Urine samples were collected and snap frozen from 34 infants attending with minor illness or feeding problems, of whom 12 infants were exclusively breastfed, nine exclusively formula fed, and 11 mixed breast/formula fed. High‐performance anion exchange chromatography was used to identify discriminating patterns of monosaccharide composition of unconjugated glycans in a sequence of three experiments. The absolute concentration of all human milk oligosaccharides measured blind could detect “any breastfeeding” only with a sensitivity of 48% and specificity of 78%. Unblinded examination of N‐acetylglucosamine (GlcNAc) measured as GlcNH2 after hydrolysis of GlcNAc improved sensitivity to 75% at the expense of a specificity of 28%. Estimation of the relative abundance of GlcNH2 (GlcNH2[%]) or the ratio of GlcNH2 to endogenous mannose (Man) improved accuracy. In a further blind experiment, the GlcNH2/Man ratio with a cut‐off of 1.5 correctly identified all those receiving “any breast milk,” while excluding exclusively formula fed infants. The GlcNH2/Man ratio in infant urine is a promising test to provide biochemical confirmation of any breastfeeding for trials of breastfeeding promotion. 相似文献
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Nitrite reductase in Streptoccocus mutans plays a critical role in the survival of this pathogen in oral cavity 总被引:1,自引:0,他引:1
BACKGROUND/AIMS: The mechanisms of nitric oxide (NO) production by bacteria in the oral cavity are still not clearly defined but salivary streptococci have been reported to generate NO. The aim of this study was to clarify the mechanism of nitrite metabolism and generation of NO by Streptococcus mutans, a major pathogen of dental caries. METHODS: We searched the genomic database of oral pathogens for nitrite reductase and used a polymerase chain reaction (PCR) to clone the nirJ gene from S. mutans GS5. His-tagged recombinant NirJ protein was expressed in Escherichia coli BL21 and characterized. We constructed a nirJ gene-disrupted mutant strain of S. mutans (DeltanirJ) to analyze the physiological significance of nirJ. RESULTS: S. mutans generates NO from nitrite, probably as a result of the possession of nitrite reductase. We cloned the nirJ gene from S. mutans GS5 by PCR. The recombinant NirJ protein catalyzed the reduction of nitrite with a K(m) value of 3.37 microM and a specific activity of 2.5 micromol/min/mg of protein at 37 degrees C. Biochemical analysis revealed that the nitrite-reducing activity of the mutant (DeltanirJ) strain was significantly lower than that of the wild-type strain. The growth of the mutant strain, but not of the wild-type strain, was strongly suppressed by the presence of physiological levels of nitrite ( approximately 0.2 mM) in saliva. CONCLUSION: These observations suggest that the elimination of nitrite and/or the generation of NO are important for the survival of S. mutans in the oral cavity. 相似文献
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Ajit Kumar Pati Bibhuti Bhusan Nayak Arun Kumar Choudhury Debesh Kumar Rout 《Indian Journal of Plastic Surgery》2014,47(3):423-426
Primary intra osseous venous malformation with involvement of nasal bone is a rare phenomenon. Nasal bone intraosseous venous malformation on a back ground of port wine stain of face has not been reported in the available literature. We report the very rare case of intraosseous venous malformation of left nasal bone developing on a background of port wine stain of face, its diagnosis, pathology, management and review of literature.KEY WORDS: Intraosseous venous malformation, nasal bone, port wine stain, sun burst appearance 相似文献
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Background
The robotic platform might offer superior ergonomics over other minimally invasive approaches. However, the increased time required for instrument set-up, operations, and surgical training are perceived as major drawbacks. There is limited literature on this topic, therefore we report our experience at an academic tertiary medical center in the USA. The primary aim of this study was to analyze the learning curve and the times for necessary steps for singly docked totally robotic Roux-en-Y gastric bypass (RREYGB).Materials and methods
From November 2010 to April 2013, all consecutive patients who underwent RREYGB were retrospectively analyzed from a prospectively maintained database. Variables of interest for this study were patient demographics, preoperative body mass index, previous surgical history, clinically relevant perioperative events, and operative times for various steps in the procedure.Results
During the study period, a total of 32 patients were enrolled. The mean age was 39.9 ± 9.7 years (range 25–60), preoperative weight was 120.9 ± 21.5 kg (range 76.7–184.6), and body mass index (BMI) was 44.7 ± 5.3 kg/m2 (range 36.1–61). The mean total operative time was 187.3 ± 36.4 min (range 130–261). The time necessary for trocar placement was 11.9 ± 4.5 min (range 4–23), robot set-up was 8.5 ± 3.6 min (range 3–20), pouch creation was 32 ± 10.11 min (range 16–56), gastrojejunal anastomosis was 59.5 ± 12.3 min (range 39–90), jejunojejunal anastomosis was 33.5 ± 9.6 min (range 18–65), and endoscopy/hemostasis was 12.9 ± 7.2 min (range 2–34). Operative time significantly improved after eight cases.Conclusion
In a high-volume established robotic bariatric center, robot set-up, operative times, and learning curve are shorter than previously reported. 相似文献10.
Jigar N. Patel Amit Kumar Partap Singh Yadav Rajiv Chadha Vikram Datta Subhasis Roy Choudhury 《Journal of pediatric surgery》2018,53(8):1560-1565