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Oral vaccines for polio (OPV) and rotavirus are less effective in children in the developing world. The reasons for this are not well understood. We tested for risk factors for poor response to OPV in infants from an urban slum of Dhaka, Bangladesh. Diminished serum neutralizing response to OPV, but not failure of intramuscularly administered vaccines, was associated with malnutrition, diarrhea, and shorter breastfeeding duration. Children with malnutrition (WAZ <−2) had significantly lower OPV 3 titers (p = 0.029). Children who had 2 or more diarrhea episodes during the 1st months of life were more than twice as likely to experience OPV failure as those who had 1 diarrhea episode or no diarrhea (p = 0.0245). In contrast, each additional month in exclusive breastfeeding was associated with an increase in OPV 3 titer by 0.41 (p = 0.0072) and 0.16 (p = 0.0065) at the 25th and 50th percentiles of OPV 3 titers respectively. These data are consistent with a defect in induction of immunity in the gut for OPV but not parenteral vaccines, a defect that may be amenable to intervention in part via promotion of exclusive breastfeeding.  相似文献   
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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   
106.

Summary

We systematically reviewed the literature on the performance of osteoporosis absolute fracture risk assessment instruments. Relatively few studies have evaluated the calibration of instruments in populations separate from their development cohorts, and findings are mixed. Many studies had methodological limitations making susceptibility to bias a concern.

Introduction

The aim of this study was to systematically review the literature on the performance of osteoporosis clinical fracture risk assessment instruments for predicting absolute fracture risk, or calibration, in populations other than their derivation cohorts.

Methods

We performed a systematic review, and MEDLINE, Embase, Cochrane Library, and multiple other literature sources were searched. Inclusion and exclusion criteria were applied and data extracted, including information about study participants, study design, potential sources of bias, and predicted and observed fracture probabilities.

Results

A total of 19,949 unique records were identified for review. Fourteen studies met inclusion criteria. There was substantial heterogeneity among included studies. Six studies assessed the WHO’s Fracture Risk Assessment (FRAX) instrument in five separate cohorts, and a variety of risk assessment instruments were evaluated in the remainder of the studies. Approximately half found good instrument calibration, with observed fracture probabilities being close to predicted probabilities for different risk categories. Studies that assessed the calibration of FRAX found mixed performance in different populations. A similar proportion of studies that evaluated simple risk assessment instruments (≤5 variables) found good calibration when compared with studies that assessed complex instruments (>5 variables). Many studies had methodological features making them susceptible to bias.

Conclusions

Few studies have evaluated the performance or calibration of osteoporosis fracture risk assessment instruments in populations separate from their development cohorts. Findings are mixed, and many studies had methodological limitations making susceptibility to bias a possibility, raising concerns about use of these tools outside of the original derivation cohorts. Further studies are needed to assess the calibration of instruments in different populations prior to widespread use.  相似文献   
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During the past decade, several peptides containing Arg‐Gly‐Asp sequence have been conjugated with different chelating agents for labeling with various radionuclides for the diagnosis of tumor development. In this study, we report the synthesis of two tetrapeptides (Asp‐Gly‐Arg‐His and Asp‐Gly‐Arg‐Cys) and one hexapeptide [Asp‐Gly‐Arg‐D‐Tyr‐Lys‐His] by changing the amino acid sequence of the Arg‐Gly‐Asp motif. Peptide synthesis was initiated from aspartic acid. Aspartic acid placed at C‐terminal end of the peptide chain can be conjugated with different drug molecules facilitating their transport to the site of action. The peptides were synthesized in excellent yield and labeled using freshly prepared [99mTc(CO)3(H2O)3]+ intermediate. A complexation yield of over 97% was achieved under mild conditions even at low ligand concentrations of 10?2 m . Radiolabeled peptides were characterized by HPLC and were found to be substantially stable in saline, in His solution as well as in rat serum and tissue (kidney, liver) homogenates. Internalization studies using Ehrlich ascites carcinoma cell line showed rapid and significant internalization (30–35% at 30 min of incubation attaining maximum value of about 40–60% after 2–4 h incubation). A good percentage of quick internalization was also observed in αvβ3‐receptor‐positive B16F10 mouse melanoma cell line (14–16% after 30 min of incubation and 25–30% after 2–4 h incubation). Imaging and biodistribution studies were performed in Swiss albino mice bearing Ehrlich ascites tumor in right thigh. Radiolabeled peptides exhibited fast blood clearance and rapid elimination through the urinary systems. 99mTc(CO)3‐tetra‐Pep2 exhibited remarkable localization at tumor site (1.15%, 1.17%, and 1.37% ID/g at 2, 4, and 6 h p.i., respectively) which could be due to slow clearance of the radiolabeled peptide from blood in comparison with the other two radiolabeled peptides. However, 99mTc(CO)3‐hexa‐Pep exhibited the highest tumor to muscle and tumor to blood ratios among the three. The preliminary results with these amino acid–based peptides are encouraging enough to carry out further experiments for targeting tumor.  相似文献   
108.
Conventional treatment strategies for catecholaminergic polymorphic ventricular tachycardia (CPVT) include avoidance of strenuous exercise and competitive sports, drugs such as ß-blockers and flecainide and, cervical sympathectomy. An implantable cardioverter-defibrillator (ICD) has been utilized if the response to these strategies is inadequate; however, ICD use in CPVT patients, in addition to usual complications, is associated with an increased risk of life-threatening electrical storm. Ivabradine is a selective inhibitor of hyperpolarization-activated cyclic nucleotide-gated potassium channel 4 generated funny current (If), which has been shown to be efficacious in suppression of inappropriate sinus tachycardia, junctional tachycardia, atrial tachycardia, and ventricular ectopy in humans. We report an 18-year-old male with a severe CPVT phenotype refractory to flecainide, nadolol, and sympathectomy who exhibited suppression of ventricular arrhythmias after initiation of ivabradine. These findings are of importance as ivabradine could be an important add-on therapy in CPVT patients who are drug refractory or are unable to continue conventional therapies at the recommended doses.  相似文献   
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110.

Background

The upper gastrointestinal (UGI) series is the preferred method for the diagnosis of malrotation. A bedside UGI technique was developed at our institution for use in low birth weight, critically ill neonates to minimize the risks of transportation from the neonatal intensive care unit (NICU) such as hypothermia and dislodgement of support lines and tubes.

Objective

To determine the ability of a bedside UGI technique to identify the position of the duodenojejunal junction (DJJ) in low birth weight, critically ill infants in the NICU.

Materials and methods

We retrospectively reviewed bedside UGI examinations performed in premature infants weighing less than 1,500 g from 2008 to 2013 and correlated the findings with clinical data, imaging studies and surgical findings.

Results

Of 27 patients identified (weight range: 633–1,495 g), 21 (78%) bedside UGI series were diagnostic. Twenty of 27 cases (74%) demonstrated normal intestinal rotation. One case demonstrated malrotation with midgut volvulus, which was confirmed at surgery. In six cases (22%), the position of the DJJ could not be accurately determined. No cases of malrotation with midgut volvulus were missed. None of the patients with normal bedside UGI studies was found to have malrotation based on clinical follow-up (mean: 20 months), surgical findings or further imaging.

Conclusion

The bedside UGI is a useful technique to exclude malrotation in critically ill neonates and minimizes potential risks of transportation to the radiology suite. Pitfalls that may preclude a diagnostic examination include incorrect timing of radiographs, patient rotation, suboptimal enteric tube position and bowel distention. In cases of diagnostic uncertainty, a follow-up study should be performed.  相似文献   
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