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111.
This study evaluated the impact of a nutrition education intervention on child feeding practices and children's nutritional status. Using a randomized controlled trial, we conducted an intervention for 6 months among caregivers with children aged 6–17 months in two subdistricts of Kendari, SE Sulawesi Province, Indonesia. In all, 22 integrated health posts were randomly assigned to an educational intervention or control group with 266 participants in both groups. Participants in the intervention group attended four nutrition classes and received a monthly home visit by cadres (community volunteers), whereas participants in the control group only received standard monthly health care at the health post. The primary study outcome was children's dietary diversity scores (DDSs). Mixed model analysis was conducted to examine the intervention effects on DDS and children's growth adjusting for clustering within subvillages. The study showed the educational intervention had a significant effect on children's DDS. Children in the intervention group had a larger DDS compared with children in the control group (Beta [mean difference] = 0.34, 95% CI: 0.02 to 0.66, P = 0.038). The intervention effect on height‐for‐age z‐score (HAZ) could not be shown (Beta = 0.24, 95% CI: ?0.06 to 0.56, P = 0.112). However, stunting prevalence remained stable in the intervention group but increased in the control group. These results indicated nutrition education delivered through nutrition classes combined with regular home visits by cadres as influencers provided a great potential to be adopted to complement other nutrition programmes in community health centres.  相似文献   
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Introduction  The study was carried out to quantify the changes induced by the pandemic in plastic surgery practice and training and to study the impact of the webinars on plastic surgery education from a residents’ perspective. Methods  In this multicentric study, the number and type of surgeries, cause of injuries, and their regional variation during the coronavirus disease 2019 (COVID-19) period (February–September 2020) were compared with pre–COVID-19 time. An online survey on the impact of webinars was conducted for plastic surgery trainees across the country. Results  There was a significant reduction in total number of surgeries ( p = 0.003). The procedures for hand ( p = 0.156), faciomaxillary injuries ( p = 0.25), and replantations ( p = 0.46) were comparable; there was a significant reduction in combined orthopedic-plastic-surgical procedures ( p = 0.009) during the pandemic. There was a significant reduction in road accidents ( p = 0.007) and suicidal injuries ( p = 0.002) and increase in assault ( p = 0.03) and domestic accidents ( p = 0.01) during the COVID-19 period. A usefulness score of >8 was given for the webinars by 68.7% residents. There was no significant difference in perception of utility when correlated with the academic program at their institutes ( p = 0.109); 92% opined webinars should continue in post-COVID times. Conclusion  There was a drastic reduction in number of elective and emergency procedures during the COVID-19 time, negatively affecting resident training program. Majority of residents felt that webinars could prove a useful adjunct to training in formal training program in post-COVID-19 scenario.  相似文献   
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Background and objectives: There are no large volume comparative studies available to compare the efficacy of lasers over lights for hair removal in Fitzpatrick V and VI skin types. This study is designed to compare the efficacy of Nd:YAG laser versus IPL in the darker skin types. Study design/materials and methods: Thirty-nine patients included in Group-1 were treated with Nd:YAG and 31 in Group-2 with IPL. Both groups received 5 sessions of treatment. The hair counts were assessed using digital photography and manual counting method before and after treatment and the results were analysed. Patient satisfaction scores and pain scores were recorded in each session and compared. Results: Mean hair reduction in the IPL group was 25.70 and Nd:YAG group was 24.12 (95% CI). In the Nd:YAG group, 59% of subjects had burning sensation while the figure was 32.3% in IPL group. Burning was less in IPL group (p < 0.023). There were no statistically significant differences noticed regarding hyperpigmentation in both the groups (p < 0.115). Conclusion: Both Nd:YAG and IPL are equally effective for epilation of the darker skin types. Nd:YAG is associated with mild burning sensation in a significant number of patients. Patient satisfaction scores were comparable in both the groups.  相似文献   
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BACKGROUND: The accurate prediction of nonsentinel node (NSN) metastasis in breast cancer patients remains uncertain. METHODS: The medical records of 574 breast cancer patients from 2 different institutions (Mayo Clinic and University of Michigan) with sentinel lymph node biopsy examination and completion axillary lymph node dissection were reviewed for multiple clinicopathologic variables. The Memorial Sloan Kettering Cancer Center nomogram performance for prediction of NSN metastases was assessed. A new model was developed with clinically relevant variables and possible advantages. RESULTS: The Memorial Sloan Kettering Cancer Center nomogram predicted the likelihood of NSN metastasis with an area under the receiver operating characteristic curve of .72 and .86. For predicted probability cut-off points of 5% and 10%, the false-negative rates were 0% and 14% (Mayo), and 17% and 11% (Michigan). A new model was developed with similar area under the curve but lower false-negative rates for low-probability subgroups. CONCLUSIONS: Predictive models for NSN tumor burden are imperfect.  相似文献   
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Leukocyte homing driven by the chemokine CCL21 is pivotal for adaptive immunity because it controls dendritic cell (DC) and T cell migration through CCR7. ACKR4 scavenges CCL21 and has been shown to play an essential role in DC trafficking at the steady state and during immune responses to tumors and cutaneous inflammation. However, the mechanism by which ACKR4 regulates peripheral DC migration is unknown, and the extent to which it regulates CCL21 in steady-state skin and lymph nodes (LNs) is contested. Specifically, our previous findings that CCL21 levels are increased in LNs of ACKR4-deficient mice [I. Comerford et al., Blood 116, 4130–4140 (2010)] were refuted [M. H. Ulvmar et al., Nat. Immunol. 15, 623–630 (2014)], and no differences in CCL21 levels in steady-state skin of ACKR4-deficient mice were reported despite compromised CCR7-dependent DC egress in these animals [S. A. Bryce et al., J. Immunol. 196, 3341–3353 (2016)]. Here, we resolve these issues and reveal that two forms of CCL21, full-length immobilized and cleaved soluble CCL21, exist in steady-state barrier tissues, and both are regulated by ACKR4. Without ACKR4, extracellular CCL21 gradients in barrier sites are saturated and nonfunctional, DCs cannot home directly to lymphatic vessels, and excess soluble CCL21 from peripheral tissues pollutes downstream LNs. The results identify the mechanism by which ACKR4 controls DC migration in barrier tissues and reveal a complex mode of CCL21 regulation in vivo, which enhances understanding of functional chemokine gradient formation.

CCL21 is a chemokine that mediates recruitment of multiple leukocyte subsets through CCR7-mediated signaling during the steady state and inflammation. CCL21 plays crucial roles in priming adaptive immunity via governing egress of dendritic cells (DCs) from barrier tissues and T cell entry and positioning in secondary lymphoid organs (15). A well-characterized site of CCL21 gradient formation is the skin, where CCL21 is secreted by lymphatic endothelial cells (LECs) and immobilized on extracellular heparan sulfate moieties via interactions with the charged, elongated C-terminal tail of CCL21 (68). Here, immobilized CCL21 gradients are essential for interstitial DC trafficking toward lymphatic vessels (LVs) (8), after which CCL21 further contributes to LV attachment (9), infiltration (10), downstream luminal migration (11), and migration from the lymph node (LN) subcapsular sinus (SCS) to the paracortex (12). In-vitro studies have shown that the C-terminal tail of CCL21 can also be proteolytically cleaved by mature DCs to generate solubilized CCL21 (13), with signaling properties distinct from another soluble CCR7 ligand, CCL19 (14, 15). While CCL19 is dispensable for steady-state DC migration (16), important questions regarding the in vivo processing and function of cleaved CCL21 remain.Both forms of CCL21 are also ligands for the atypical chemokine receptor ACKR4 (17), which regulates chemokine bioavailability rather than directly mediating cell migration. ACKR4 expression has been identified in multiple barrier tissues (1820) and lymphoid tissues (12, 21) where expression is largely restricted to stromal cell populations, with the exception of germinal-center B cells (22). Despite clear evidence of ACKR4 scavenging of CCL21 in vitro, the extent to which it regulates CCL21 in vivo is disputed. We have shown increased CCL21 in the LNs of Ackr4−/− mice, which was associated with exacerbated Th17 responses in autoimmunity (23) and an ACKR4-dependent increase in CCL21 in tumors that promotes antitumor immunity (24). However, no differences in dermal CCL21 abundance were previously reported in steady-state Ackr4−/− mice despite steady-state CCR7-dependent DC migratory defects being independent of CCL19 (19), and the contribution of ACKR4 in regulating LN CCL21 abundance has been disputed despite a clear role for ACKR4 in maintaining interfollicular CCL21 gradients in LN (12). These discrepancies have remained unresolved but point to previously unrecognized complexity in ACKR4-dependent regulation of CCL21 in both barrier and lymphoid tissues.  相似文献   
116.
Harmful algal blooms (HABs) and their toxins are a significant and continuing threat to aquatic life in freshwater, estuarine, and coastal water ecosystems. Scientific understanding of the impacts of HABs on aquatic ecosystems has been hampered, in part, by limitations in the methodologies to measure cyanotoxins in complex matrices. This literature review discusses the methodologies currently used to measure the most commonly found freshwater cyanotoxins and prymnesins in various matrices and to assess their advantages and limitations. Identifying and quantifying cyanotoxins in surface waters, fish tissue, organs, and other matrices are crucial for risk assessment and for ensuring quality of food and water for consumption and recreational uses. This paper also summarizes currently available tissue extraction, preparation, and detection methods mentioned in previous studies that have quantified toxins in complex matrices. The structural diversity and complexity of many cyanobacterial and algal metabolites further impede accurate quantitation and structural confirmation for various cyanotoxins. Liquid chromatography–triple quadrupole mass spectrometer (LC–MS/MS) to enhance the sensitivity and selectivity of toxin analysis has become an essential tool for cyanotoxin detection and can potentially be used for the concurrent analysis of multiple toxins.  相似文献   
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Oxidant stress is believed to be enhanced in patients with diabetes mellitus, which may lead to endothelial dysfunction and the development of atherosclerosis. In diabetes, hyperglycemia drives non-enzymatic glycation and oxidation of proteins and lipids which enhances the formation of advanced glycation end products (AGEs), which may be involved in the pathogenesis of diabetic vascular disease. The macrovascular complications of diabetes seem to be due to enhanced cellular oxidant stress by the interaction of AGEs with their receptor. It would be worthwhile to devise methods to reduce this oxidant stress. In alloxan-induced diabetic rats lipid peroxidation products were increased, while levels of nitric oxide glutathione peroxidase and superoxide dismutase were reduced. Melatonin restored these biochemical abnormalities to normalcy independent of hyperglycemia. This model can be used to study the role of oxidant stress in the development of macrovascular complications in diabetes mellitus.  相似文献   
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