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Background: Diagnosing cobalamin deficiency is critical, given the high prevalence of cobalamin deficiency particularly in developing countries. Measuring serum cobalamin levels is of limited diagnostic sensitivity, in other words its specificity and sensitivity are low. The present study investigated the changes in the levels of metabolic markers – plasma homocysteine, plasma methylmalonic acid (MMA) and urinary MMA – of cobalamin metabolism.

Methods: Plasma cobalamin and serum folic acid were studied in 206 pregnant women over the last four prenatal weeks. Plasma cobalamin, folic acid, homocysteine, MMA from umbilical cord blood and urinary MMA in newborns were studied.

Results: Plasma cobalamin values were low in 66% of the mothers. There was a positive correlation between maternal and neonatal plasma cobalamin values (r?=?0.72, p?<?0.001). B12 was strongly inversely associated with plasma MMA, urine MMA and plasma homocysteine. To predict cobalamin deficiency, sensitivities of plasma MMA, urinary MMA and homocysteine were 96.4%, 95.6% and 88.2%, respectively. And positive predictive values (PPV) were 96.2%, 96.9% and 86% for plasma MMA, urinary MMA and plasma homocysteine levels, respectively.

Conclusion: Plasma MMA and urinary MMA B12 are the most robust markers of cobalamin deficiency. As a non-invasive method, urinary MMA is a sensitive method in demonstrating cobalamin deficiency in the newborn.  相似文献   
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Soft tissue expansion is a mechanical process that increases the surface area of local tissue available for reconstructive procedures. In most cases, adjacent tissue that matches the recipient site in color, texture, and hair-bearing quality is preferred for tissue expansion. In this particular case with neurocutaneous syndrome, the defects that resulted from removal of parts of a giant hairy nevus overlying the latissimus dorsi muscle bilaterally were grafted with a split-thickness skin graft. Two expanders were then placed under the latissimus dorsi muscles. After full expansion of the grafted area, some part of the remaining nevus surrounding the grafted area was removed and the defects were covered with the expanded skin graft obtained after deflation of the expanders. The expanders placed under the latissimus dorsi muscle in the first operation were reused in the second operation to obtain a second expansion of the skin graft. After the second expansion of the skin graft, the expanders were deflated and another portion of the remaining nevus surrounding the grafted area was removed. The resulting defects were again covered with the excess expanded skin graft. Although repeated expansion of the skin graft is a time-consuming and laborious process, it eliminates the need for taking repeated skin grafts; it decreases skin graft donor site morbidity; it decreases possible infectious complications of tissue expansion by decreasing the number of surgical interventions to the expander pocket; and it increases the aesthetic outcome by keeping all the surgical scars around the grafted area without extending them into healthy surrounding skin.  相似文献   
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Moyamoya syndrome is a chronic, progressive occlussion of cerebrovascular arteries that leads to the development of characteristic collateral vessels. It is usually accompanied with sickle cell disease and other hemoglobinopathies. We report a 7-year-old boy, who admitted to our clinic with headache, diagnosed as moyamoya syndrome associated with sickle cell trait. To date, two such cases have been reported in the literature. As far as we know, this patient is the first child reported.  相似文献   
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Adenosine deaminase 2 (ADA2) deficiency due to CECR1 mutations is a recently defined disorder that involves systemic inflammation and vasculopathy often associated with polyarteritis nodosa. We report on a 5-year-old girl with a severe vasculopathy who carried two novel mutations in CECR1. Conclusion: Identification of CECR1 mutations in patients with vasculopathy may lead to earlier diagnosis of ADA2 deficiency.  相似文献   
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We compared the effectiveness of ultrasound (US)-guided corticosteroid, injected superficial or deep to the fascia, in patients with plantar fasciitis. Thirty patients (24 females [75%] and 6 males [25%]) with unilateral chronic plantar fasciitis were divided into 2 groups according to the corticosteroid injection site: superficial (n = 15) or deep (n = 15) to the plantar fascia. Patient heel pain was measured using a Likert pain scale and the Foot Ankle Outcome Scale (FAOS) for foot disability, evaluated at baseline and repeated in the first and sixth weeks. The plantar fascia and heel pad thicknesses were assessed on US scans at baseline and the sixth week. The groups were similar in age, gender, and body mass index (p > .05 for all). Compared with the baseline values, the Likert pain scale (p < .001 for all) and FAOS subscale (p < .01 for all) scores had improved at the first and sixth week follow-up visits in both groups. Although the plantar fascia thickness had decreased significantly in both groups at the sixth week (p < .001 for both), the heel pad thickness remained unchanged (p > .05 for both). The difference in the FAOS subscales (pain, p = .002; activities of daily living, p = .003; sports/recreational activities, p = .008; quality of life, p = .009) and plantar fascia thickness (p = .049) showed better improvement in the deep than in the superficial injection group. US-guided corticosteroid injections are safe and effective in the short-term therapeutic outcome of chronic plantar fasciitis. Additionally, injection of corticosteroid deep to the fascia might result in greater reduction in plantar fascia thickness, pain, and disability and improved foot-related quality of life.  相似文献   
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