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Objective

To examine the association of placental levels of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), manganese (Mn), and chromium (Cr) with birth outcomes (birth weight, length, and head circumference, low birth weight [LBW], gestational age, preterm delivery, and small for gestational age [SGA]) in mother-child pairs from the Environment and Childhood (INMA) Project in Spain.

Methods

Metal concentrations were measured in placenta tissue samples randomly selected from five INMA cohorts. Data on birth outcomes were obtained from medical records. Associations were assessed in a sub-sample of 327 mother-infant pairs by regression models adjusted for confounding factors and for all metals simultaneously. Effect modification by sex was also evaluated.

Results

Elevated placental Cd levels (>5.79 vs. <3.30?ng/g) were associated with reduced birth weight (?111.8?g, 95%CI?=??215.6; ?8.06, p-trend?=?0.01) and length (?0.62?cm, 95%CI?=??1.20; ?0.04, p-trend?=?0.02), while a 10% increase in Cd was associated with 1.21-fold increased odds (95%CI?=?1.01; 1.43) of LBW in the global sample but with 14% lower odds (95%CI?=?0.78; 0.96) of preterm delivery in males (Pinteraction?=?0.10). Detected (vs. undetected) Hg was associated with reduced head circumference (?0.49?cm, 95%CI?=??1.00; 0.03) in females (Pinteraction?=?0.03). A 10% increase in placental Mn was associated with slight increases in gestational age (0.04 weeks, 95%CI?=?0.01; 0.07) in the global sample and in head circumference (0.05?cm, 95%CI?=??0.01; 0.10) in females (Pinteraction?=?0.03). Elevated Cr levels (>99.6 vs. <56.1?ng/g) were associated with reduced birth length (?0.68?cm, 95%CI?=??1.33; ?0.04, p-trend?=?0.02) and slightly increased gestational age (0.35 weeks, 95%CI?=??0.07; 0.77, p-trend?=?0.08) in the global sample. As and Pb were detected in few placentas (27% and 13%, respectively) and were not associated with any studied birth outcome.

Conclusions

Data suggest that in utero exposure to Cd, Hg, and Cr could adversely affect fetal growth, whereas Mn and Cr appear to have a positive effect on gestational age. Given the relatively small number of subjects, sex-specific associations should be interpreted with caution.  相似文献   
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IntroductionThere is a lack of scientific studies on the assessment of patients with vestibular disorders associated with sleep quality disorders and its impact on the balance and overall quality of life.Objectivesto assess the impact of the sleep quality on the balance and quality of life of individuals with peripheral vestibulopathies.Methods52 individuals with peripheral vestibulopathies underwent sleep quality assessment through the Pittsburgh sleep quality index, neurotological examination through dizziness handicap inventory and Tetrax posturography (Sunlight Medical Ltd.) in eight sensory conditions. Thirty-two healthy individuals (G3) participated as the control group.ResultsFourteen individuals with vestibulopathy had good quality of sleep (G1) and 38 showed poor quality of sleep (G2) as demonstrated by the Pittsburgh sleep quality index global scores (p = 0.001). The dizziness handicap inventory showed worse impact of the dizziness on the quality of life in G2 when compared to G1 (p  = 0.045). The G2 showed higher risk of falling in posturography when compared to G3 (p = 0.012) and higher index of postural instability in five sensory conditions in comparison with G3. In the vestibulopathy groups, the worse the sleep quality, the higher the risk of falling (r = 0.352) and the worse the quality of life (r = 0.327).ConclusionIndividuals with peripheral vestibulopathies and poor quality of sleep demonstrate worse balance evidenced by increased postural instability, higher risk of falls and worse perceived quality of life. The quality of sleep is a predictive factor for worse perceived quality of life and for higher risk of falls in individuals with peripheral vestibulopathies.  相似文献   
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Economically relevant pathogens, such as African swine fever virus (ASFV), have been shown to survive when experimentally inoculated in some feed ingredients under the environmental conditions in transoceanic transport models. However, these models did not characterize the likelihood of virus survival under various time and temperature processes that feed ingredients undergo before they are added to swine diets. Here, we developed a quantitative risk assessment model to estimate the probability that one or more corn or soybean meal ocean vessels (25,000 tonnes) contaminated with ASFV would be imported into the United States annually. This final probability estimate was conditionally based on five likelihoods: the probability of initial ASFV contamination (p0), ASFV inactivation during processing (p1) and transport (p2), recontamination (pR), and ASFV inactivation while awaiting customs clearance at United States entry (p3). The probability of ASFV inactivation was modelled using corn and soybean (extruded or solvent extracted) processing conditions (times and temperatures), D-values (time to reduce 90% or 1-log) estimated from studies of ASFV thermal inactivation in pork serum (p1), and survival in feed ingredients during transoceanic transport (p2 and p3). ‘What-if’ scenarios using deterministic values for p0 and pR (1%, 10%, 25%, 50%, 75%, and 100%) were used to explore their impact on risk. The model estimated complete inactivation of ASFV after extrusion or solvent extraction processes regardless of the initial ASFV contamination probability assumed. The value of recontamination (ranging from 1% to 75%) was highly influential on the risk of one ASFV-contaminated soybean meal vessel entering the United States. Median risk estimates ranged from 0.064% [0.006%–0.60%; 95% probability interval (PI)], assuming a pR of 1.0%, up to 4.67% (0.45%–36.50% 95% PI) assuming a pR of 75.0%. This means that at least one vessel with ASFV-contaminated soybean meal would be imported once every 1563–21 years, respectively. When all raw corn was assumed to be contaminated (p0 = 100%), and no recontamination was assumed to occur (pR = 0%), the median probability of one vessel with ASFV-contaminated corn entering the United States was 2.02% (0.28%–9.43% 95% PI) or once every 50 years. Values of recontamination between 1% and 75% did not substantially change the risk of corn. Days of transport, virus survival during transport (D-value), and number of vessels shipped were the parameters most influential for increased likelihood of a vessel with ASFV-contaminated soybean meal or corn entering the United States. The model helped to identify knowledge gaps that are most influential on output values and serves as a framework that could be updated and parameterized as new scientific information becomes available. We propose that the quantitative risk assessment model developed in this study can be used as a framework for estimating the risk of ASFV entry into the United States and other ASFV-free countries through other types of imported feed ingredients that may potentially become contaminated. Ultimately, this model can be used to develop risk mitigation strategies and critical control points for inactivating ASFV during feed ingredient processing, storage, and transport, and contribute to the design and implementation of biosecurity measures to prevent the introduction of ASFV into the United States and other ASFV-free countries.  相似文献   
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Acinar cell carcinoma (ACC) is a rare pancreatic malignancy with distinctive clinical, molecular, and morphological features. The long-term survival of ACC patients is substantially superior to that of pancreatic adenocarcinoma patients. As there are no significant patient series about ACCs, our understanding of this illness is mainly based on case reports and limited patient series. Surgical resection is the treatment of choice for patients with the disease restricted to one organ; however, with recent breakthroughs in precision medicine, medicines targeting the one-of-a-kind molecular profile of ACC are on the horizon. There are no standard treatment protocols available for people in which a total surgical resection to cure the condition is not possible. As a result of shared genetic alterations, ACCs are chemosensitive to agents with activity against pancreatic adenocarcinomas and colorectal carcinomas. The role of neoadjuvant or adjuvant chemoradiotherapy has not been established. This article aims to do a comprehensive literature study and present the most recent information on acinar cell cancer.  相似文献   
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This study analyzes the dimensional changes of the glands from prostate cancer by applying stereology to estimate the variations in volume, length, surface, and cellular densities of tumor acini. Normal and tumor acini were visualized using immunohistochemistry for cytokeratin18. On immunostained sections, parameters related to the dimensions and cell population of prostate acini were measured. The immunohistochemical expression of proliferative cell nuclear antigen was also measured to correlate the quantitative changes estimated with the proliferative activity of the epithelium. The average cell volume in normal and tumor epithelium was estimated using the method of the nucleator. The relative size of the acini was similar in the carcinoma compared with the normal prostate. Within the acini, the fraction of acinar volume occupied by the epithelium was significantly higher in cancer than in the nontumor prostate. Conversely, the glandular lumen of the cancer acini is lower than in the normal acini. The significant increase of acinar length density in the carcinoma indicates that the glandular tree's growth in the carcinoma is higher and with more branches than in the case of nonneoplastic glands. The basal surface density is higher in the carcinoma than in the controls. The number of epithelial cells per unit length of acini was significantly decreased in the neoplastic glands. This "dilution" of the cell population along the cancer acinus can be explained by the significant increase in the tumor cell's mean cell volume.  相似文献   
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