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1.
Objectives. We recruited 248 farmworker families with preschool-aged children in North Carolina and examined food security indicators over 24 months to identify food security patterns and examine the dynamic of change over time.Methods. Participants in the Niños Sanos study, conducted 2011 to 2014, completed quarterly food security assessments. Based on responses to items in the US Household Food Security Survey Module, we identified different states of food security by using hidden Markov model analysis, and examined factors associated with different states. We delineated factors associated with changes in state by using mixed-effect ordinal logistic regression.Results. About half of the households (51%) consistently stayed in the most food-secure state. The least food-secure state was transient, with only 29% probability of this state for 2 consecutive quarters. Seasonal (vs migrant) work status, having immigration documents (vs not documented), and season predicted higher levels of food security.Conclusions. Heterogeneity in food security among farmworker households calls for tailoring intervention strategies. The transiency and unpredictability of low food security suggest that access to safety-net programs could reduce low food security risk in this population.Farmworkers in the United States experience challenging living conditions and economic insecurity because of low-paying and contingent employment. Although an exact number of farmworkers is not available, estimates place the population at 900 000, plus dependents.1 This includes migrant farmworkers, who establish temporary residences to do farm work, as well as seasonal workers who reside in one place and do farm work during the agricultural season.2 Currently, most farmworkers are Latino and foreign-born,3 which can limit their eligibility and access to food safety-net programs such as the Supplemental Nutrition Assistance Program. In addition, many reside in rural areas where access to healthy food retail stores may be limited by both availability and transportation, although home food production is sometimes possible.4 Together, these create a situation in which farmworker households are likely to experience low food security (resulting from insufficient household resources), but this may be episodic. Children in farmworker households may be particularly vulnerable to the effects of low food security.5Low food security is associated with negative developmental outcomes in infants and toddlers.6 Persistently low food security in early childhood is associated with long-term lower health status.7 For children at school age, this can adversely affect academic performance, weight gain, and social skills.8 With the large population of farmworkers in the United States, food security among their families is an important public health issue.Previous reports of food security for farmworker households have found 20% to 80% to be food insecure.9–14 However, all of these reports have been cross-sectional, and most have used an extended recall period, asking respondents to recall whether their household was food insecure at any time during the past year. Such data provide no information on the duration of food security states or on factors associated with transitions in and out of low food security. Examining food security over time as a dynamic construct is necessary to understand its duration and to develop protective measures for low food security.This repeated-measures study gathered data quarterly for 24 months, and examined different states of food security by using the 18-item US Household Food Security Survey Module.15 Instead of constructing a single score, we used the full item set to form a food security profile. The approach allowed us to delineate several different states of food security within the food security profile, and examine the dynamic of change in food security over the 24-month period. The aims of the study were to (1) describe multiple states of food security of farmworker households, (2) identify factors associated with the different food security states, and (3) delineate the dynamic of change in food security states across a period of 24 months.  相似文献   
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Metals are among the most prevalent pollutants released into the environment. For these reasons, the use of biomarkers for environmental monitoring of individuals and populations exposed to metal pollution has gained considerable attention, offering fast and sensitive detection of chemical stress in organisms. There are different metal resistance genes in bacteria that can be used as biomarkers, including cation diffusion facilitators carrying metal ions; the prototype is the cobalt–zinc–cadmium transporter (czcD). The present study reports the expression changes in the czcD gene in Bacillus megaterium and Microbacterium liquefaciens under nickel and vanadium exposure by real-time polymerase chain reaction. The nickel–vanadium-resistant strains of B. megaterium and M. liquefaciens used in this study were isolated from mine tailings in Guanajuato, Mexico. The czcD gene showed high expression under exposure to 200 ppm of Ni and 200 ppm of V during the logarithmic growth phase of M. liquefaciens in PHGII liquid media. In contrast, no changes were observed in B. megaterium during logarithmic and stationary growth, perhaps due to the gene having differential expression during the growth phases. The expression profiles obtained for czcD show the possibility of using this gene from M. liquefaciens as a biomarker of nickel and vanadium pollution in microorganisms.  相似文献   
4.
Mutations in GBA1, the gene mutated in Gaucher disease, are a common genetic risk factor for Parkinson disease, although the penetrance is low. We performed [18F]-fluorodopa positron emission tomography studies of 57 homozygous and heterozygous GBA1 mutation carriers (15 with parkinsonism) and 98 controls looking for early indications of dopamine loss using voxelwise analyses to identify group differences in striatal [18F]-fluorodopa uptake (Ki). Forty-eight subjects were followed longitudinally. Cross-sectional and longitudinal comparisons of Ki and Ki change found significant effects of Parkinson disease. However, at baseline and over time, striatal [18F]-fluorodopa uptake in mutation carriers without parkinsonism did not significantly differ from controls. ANN NEUROL 2020;87:652–657  相似文献   
5.
Sex specificity of neural mechanisms modulating nociceptive information has been demonstrated in rodents, and these qualitative sex differences appear to be relevant to analgesia from kappa-opioid receptor agonists, a drug class reported to be clinically effective only in women. Via quantitative trait locus mapping followed by a candidate gene strategy using both mutant mice and pharmacological tools, we now demonstrate that the melanocortin-1 receptor (Mc1r) gene mediates kappa-opioid analgesia in female mice only. This finding suggested that individuals with variants of the human MC1R gene, associated in our species with red hair and fair skin, might also display altered kappa-opioid analgesia. We found that women with two variant MC1R alleles displayed significantly greater analgesia from the kappa-opioid, pentazocine, than all other groups. This study demonstrates an unexpected role for the MC1R gene, verifies that pain modulation in the two sexes involves neurochemically distinct substrates, and represents an example of a direct translation of a pharmacogenetic finding from mouse to human.  相似文献   
6.
Acquired tracheoesophageal fistulas (TEF) are rare but dangerous complications of disc-battery ingestion. Management approaches include endoscopic or open surgical repair. Unfortunately, these procedures can be complicated by high rates of recurrent laryngeal nerve injury, tracheal stenosis, recurrent fistula and significant patient mortality. Thus, several authors have advocated the use of esophageal rest as conservative management of acquired TEF to permit closure by secondary intention. This study describes a patient with spontaneous closure of an acquired TEF following disc-battery ingestion. The late recurrence of the TEF following conservative management, and endoscopic and radiographic evidence of closure, illustrates the importance of long term evaluation before assuming fistula resolution. Practitioners must carefully weigh the risks and benefits before deciding surgical versus conservative management of TEF. An extended follow-up of at least 6 months should be instituted with a high index of suspicion if conservative management is utilized. Transtracheal repair using an imbricated suture technique is a good surgical option when conservative management fails.  相似文献   
7.
Many nonmotor fluctuations (NMFs) may occur in addition to the classic motor fluctuations (MFs) in patients with Parkinson's disease (PD) within several years of initiation of dopaminergic treatment. Patients can experience these NMFs in the "on" and/or "off" periods. NMFs can be divided into three groups: Autonomic, cognitive/psychiatric, and sensory. Nonmotor sensory fluctuations (NMSFs) occurring in association with "on" period are more frequently recognized than those in the "off" state. NMSFs commonly reported include pain, numbness, paresthesia/dysesthesia, akathisia, rest-legs syndrome (RLS), dyspnea, and internal tremor (IT). Proposed treatments of NMSFs are based on whether they occur during "off" or "on" state. These include reduction of dopaminergic medication, use of long-acting dopamine agonists or controlled released levodopa (LD), surgical intervention, and/or targeted pharmacological intervention to minimize dopaminergic side effects. NMSFs might be related to dopaminergic mechanisms although difficulty in managing these symptoms with dopaminergic therapy suggests a different pathway. Conclusion: Recognition of NMSFs is important in the care of patients with Parkinson disease to prevent unnecessary interventions and for appropriate medication regimen adjustments.  相似文献   
8.
In clinical and forensic toxicology, general unknown screening is used to detect and identify exogenous compounds. In this study, we aimed to develop a fast (15 min) comprehensive screening method for 500 toxicologically relevant analytes based on ultra-performance liquid chromatography (UPLC) coupled with a quadrupole mass spectrometer (MS) system operated in full scan mode. Data were acquired using both positive and negative electrospray ionization by scanning across the range m/z 80-650. For each ionization mode, data were also collected under multiple fragmentation conditions (i.e., at six different cone voltages). Consequently, each molecule could be characterized by a combination of retention time and up to a maximum of 12 individual spectra. Investigation of the 500 analytes resulted in the compilation of a library containing 2975 spectra. An assessment of the stability of these spectra was evaluated under various conditions, that is, the impact of increasing drug concentration and the presence of biological matrix. In addition, the transferability of the spectral library was assessed by comparison with data acquired using several other instruments of same model and from the same manufacturer. These data are presented in addition to the utility of the method for the analysis of routine clinical and forensic samples. Following extraction, identified compounds were compared to those found with two other techniques, one based on immunoassay and the other, on high-performance liquid chromatography-photodiode-array.  相似文献   
9.
PURPOSE The patient-physician relationship is the cornerstone of health care service delivery. The objectives of this study were to assess the contribution of relationship commitment along with trust to patient-physician relationships and to evaluate the association of commitment and trust with adherence to medical advice and healthy eating behaviors.METHODS To test the proposed model, we developed a questionnaire that included both existing scales and a scale constructed specifically for the study; the questions addressed trust, commitment, adherence to physicians’ medical recommendations, and healthy eating behavior. The questionnaire was given to adult patients in the waiting rooms of 4 large clinics in central Texas.RESULTS A total of 1,008 patients returned questionnaires; 869 patients’ questionnaires were complete and used in the analysis. A 3-stage least squares analysis that tested a system of 4 equations which included relationship commitment yielded a systemwide R2 of 0.71 that was 0.09 higher than a system of equations excluding relationship commitment. Trust and commitment were positively associated with adherence (P <.001 and P = .02, respectively). We also found positive relationships between adherence and commitment and between trust and commitment (P <.001 for each). Adherence and commitment were both associated with healthy eating behavior as well (P <.001 for each).CONCLUSIONS Patients’ trust in their physician and commitment to the relationship offer a more complete understanding of the patient-physician relationship. In addition, trust and commitment favorably influence patients’ health behaviors.  相似文献   
10.
The sequence effect (SE) in Parkinson's disease (PD) is progressive slowing of sequential movements. It is a feature of bradykinesia, but is separate from a general slowness without deterioration over time. It is commonly seen in PD, but its physiology is unclear. We measured general slowness and the SE separately with a computer‐based, modified Purdue pegboard in 11 patients with advanced PD. We conducted a placebo‐controlled, four‐way crossover study to learn whether levodopa and repetitive transcranial magnetic stimulation (rTMS) could improve general slowness or the SE. We also examined the correlation between the SE and clinical fatigue. Levodopa alone and rTMS alone improved general slowness, but rTMS showed no additive effect on levodopa. Levodopa alone, rTMS alone, and their combination did not alleviate the SE. There was no correlation between the SE and fatigue. This study suggests that dopaminergic dysfunction and abnormal motor cortex excitability are not the relevant mechanisms for the SE. Additionally, the SE is not a component of clinical fatigue. Further work is needed to establish the physiology and clinical relevance of the SE. © 2010 Movement Disorder Society.  相似文献   
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