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de Paula Martins W Santana LF Nastri CO Ferriani FA de Sa MF Dos Reis RM 《European journal of obstetrics, gynecology, and reproductive biology》2007,133(2):203-207
OBJECTIVE: The objective was to compare agreement on the diagnosis of insulin resistance (IR) among insulin sensitivity indexes in both ovulatory women and those with polycystic ovary syndrome (PCOS). STUDY DESIGN: In an observational study, the 75-g oral glucose tolerance test was performed in 105 women with PCOS and 51 ovulatory women. The insulin sensitivity indexes used were insulin quantitative sensitivity check index (QUICKI), 1/homeostasis model assessment-insulin resistance (1/HOMA-IR), area under curve for insulin (AUC-I), and the Matsuda insulin sensitivity index (COMP). For the IR diagnosis we used cut-off values described in recent publications (insulin >12 microIU/ml, 1/HOMA-IR <0.47, QUICKI < or =0.333, AUC-I > or =7000 microIU/ml 120 min, and COMP <4.75. RESULTS: Excellent agreement was assessed among insulin, QUICKI, and 1/HOMA-IR. However, the rate of IR detected by these indexes in the PCOS group (44.8-51.4%) was lower than expected. New cut-offs were then determined based on COMP results. Using these values, 1/HOMA-IR and QUICKI showed excellent agreement (kappa=0.83) with COMP. CONCLUSION: The observed agreements among insulin, QUICKI and 1/HOMA-IR were higher than 93%. Therefore, clinicians may choose any of those obtaining similar results. For clinicians who prefer COMP, but are looking for a simpler test to detect IR in PCOS women, the use of QUICKI and 1/HOMA-IR with the new cut-offs seems reasonable. 相似文献
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Rosa e Silva AC Rosa e Silva JC Reis RM Tone LG Silva de Sá MF Ferriani RA 《Journal of pediatric and adolescent gynecology》2007,20(2):89-91
STUDY OBJECTIVE: To determine the presence of impaired gonadal function in adolescent patients submitted to chemotherapy during childhood or during the pubertal period. DESIGN: A case series study of 28 patients aged 12 to 19 years with menarche at least 2 years before the study. SETTING: Tertiary care public hospital. PARTICIPANTS: Group I: 14 adolescents previously submitted to chemotherapy during the prepubertal or peripubertal period and with remission of oncologic disease for at least 2 years; Group II: 14 normal adolescents with no previous oncologic disease and with regular menstrual cycles. INTERVENTIONS AND MAIN OUTCOME MEASURES: Pubertal development, menstrual cycles and serum levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were determined during the early follicular phase. RESULTS: There were no differences between the two groups in terms of age at appearance of secondary sexual characteristics or age at menarche. Menstrual irregularity was detected in 7 of the 14 patients in Group I, all 8 of whom presented oligomenorrhea. There were no differences in LH levels between the two groups (P = 0.55), although mean FSH levels were higher in Group I than in Group II (6.71 +/- 2.99 mIU/ml vs. 3.83 +/- 2.01 mIU/ml, P = 0.01). CONCLUSION: Although girls submitted to chemotherapy during the prepubertal or peripubertal period presented normal sexual development, the incidence of oligomenorrhea was higher than expected for their age, and FSH levels, although within normal limits, were higher than those seen in normally cycling girls. 相似文献
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Carolina Gasparinho Maria Helena Gonalves Assucênio Chissaque Giovani L. Silva Filomeno Fortes Luzia Gonalves 《Nutrients》2022,14(11)
Undernutrition, anemia, and intestinal parasitic infections are public health problems in Angola, especially in pre-school children. We analyzed binary data from a longitudinal four-arm randomized parallel trial conducted in Bengo Province, northern Angola, over the course of two years, with seven follow-up assessments to explore the effects of four interventions (deworming and a test-and-treat approach for intestinal parasites, at both the individual and household levels) on wasting and stunting, and to understand their indirect benefits for anemia, malaria, diarrhea, and vomiting. A total of 121 children with intestinal parasitic infections received baseline treatment, and were allocated to the four arms (1:1:1:1). Using continuous outcome variables of height-for-age (HAZ) and weight-for-height (WHZ) statistical approaches did not reveal a clear benefit of any particular arm (Pathogens 2021, 10, 309). Next, HAZ and WHZ were transformed into binary variables of stunting and wasting, respectively, considering their mild-to-severe (Z-score < −1) and moderate-to-severe degrees (Z-score < −2). Original clinical data (on anemia, diarrhea, vomiting, and malaria) were also analyzed. From a binary longitudinal analysis with different dependence structures, using the R package bild, fitted models revealed the potential benefit of a test-and-treat approach at the individual level for wasting compared with annual albendazole at the individual level, especially considering mild-to-severe forms (ORadj = 0.27; p = 0.007). All arms showed similar effects on stunting, compared with annual albendazole, at a 5% significance level. Time and age at baseline presented favorable effects in the percentage of stunting using both severity degrees. Results showed a decreased chance of having anemia and diarrhea over time, although with no significant differences between arms. Data from longitudinal studies are essential to study the direct and indirect effects of interventions, such as deworming, and to explore additional approaches aiming at better understanding the temporal structure of nutrition and health outcomes in children. 相似文献
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Amy C. Morrison Robert C. Reiner Jr. William H. Elson Helvio Astete Carolina Guevara Clara del Aguila Isabel Bazan Crystyan Siles Patricia Barrera Anna B. Kawiecki Christopher M. Barker Gissella M. Vasquez Karin Escobedo-Vargas Carmen Flores-Mendoza Alfredo A. Huaman Mariana Leguia Maria E. Silva Sarah A. Jenkins Wesley R. Campbell Eugenio J. Abente Robert D. Hontz Valerie A. Paz-Soldan John P. Grieco Neil F. Lobo Thomas W. Scott Nicole L. Achee 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(26)
Over half the world’s population is at risk for viruses transmitted by Aedes mosquitoes, such as dengue and Zika. The primary vector, Aedes aegypti, thrives in urban environments. Despite decades of effort, cases and geographic range of Aedes-borne viruses (ABVs) continue to expand. Rigorously proven vector control interventions that measure protective efficacy against ABV diseases are limited to Wolbachia in a single trial in Indonesia and do not include any chemical intervention. Spatial repellents, a new option for efficient deployment, are designed to decrease human exposure to ABVs by releasing active ingredients into the air that disrupt mosquito–human contact. A parallel, cluster-randomized controlled trial was conducted in Iquitos, Peru, to quantify the impact of a transfluthrin-based spatial repellent on human ABV infection. From 2,907 households across 26 clusters (13 per arm), 1,578 participants were assessed for seroconversion (primary endpoint) by survival analysis. Incidence of acute disease was calculated among 16,683 participants (secondary endpoint). Adult mosquito collections were conducted to compare Ae. aegypti abundance, blood-fed rate, and parity status through mixed-effect difference-in-difference analyses. The spatial repellent significantly reduced ABV infection by 34.1% (one-sided 95% CI lower limit, 6.9%; one-sided P value = 0.0236, z = 1.98). Aedes aegypti abundance and blood-fed rates were significantly reduced by 28.6 (95% CI 24.1%, ∞); z = −9.11) and 12.4% (95% CI 4.2%, ∞); z = −2.43), respectively. Our trial provides conclusive statistical evidence from an appropriately powered, preplanned cluster-randomized controlled clinical trial of the impact of a chemical intervention, in this case a spatial repellent, to reduce the risk of ABV transmission compared to a placebo.Aedes-borne viral diseases (ABVDs) [e.g., dengue (DENV), chikungunya, Zika (ZIKV), and yellow fever] are devastating, expanding global public health threats that disproportionally affect low- and middle-income countries. DENV, one of the most rapidly increasing vector-borne infectious diseases, results in ∼400 million infections each year (1, 2), with 4 billion people at risk for infection annually (3). Currently, the primary means for ABVD prevention is controlling the primary mosquito vector, Aedes aegypti. Existing vector control interventions, however, have failed to prevent ABV transmission and epidemics (4–6).There is an urgent need to develop evidence-based guidance for the use of new and existing ABV vector control tools. The evidence base for vector control against ABVs is weak, despite considerable government investments in World Health Organization (WHO)-recommended control of larval habitats (larviciding, container removal) and ultra-low-volume insecticide spraying (4, 5, 7–9). These strategies continue to be implemented despite the lack of rigorously generated data from controlled clinical trials demonstrating they reduce ABV infection or disease (6). The only ABV intervention with a proven epidemiological impact in a cluster-randomized control trial (cRCT) assessed community mobilization to reduce mosquito larval habitats (10). A recent test-negative trial with Wolbachia-infected mosquitoes reported a significant reduction of DENV illness in Indonesia (11).Spatial repellents (SRs) are devices that contain volatile active ingredients that disperse in air. The active ingredients can repel mosquitoes from entering a treated space, inhibit attraction to human host cues, or disrupt mosquito biting and blood-feeding behavior and, thus, interfere with mosquito–human contact (12–14). Any of these outcomes reduce the probability of pathogen transmission. Pyrethroid-based SRs have shown efficacy in reducing malaria infections in China (15) and Indonesia (16). There have, however, been no clinical trials evaluating the protective efficacy (PE) of SRs against ABV infection or disease.To generate evidence for public health consideration, we conducted a double-blinded, parallel cRCT to demonstrate and quantify the PE of a transfluthrin-based SR to reduce ABV infection incidence over 2 y in a human cohort in Iquitos, Peru. 相似文献
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Karmele Valencia Marta Martín-Fernández Carolina Zandueta Cristina Ormazábal Susana Martínez-Canarias Eva Bandrés Concepción de la Piedra Fernando Lecanda 《BONE》2013,52(1):532-539
Recent evidence suggests that miRNAs could be used as serum markers in a variety of normal and pathological conditions. In this study, we aimed to identify novel miRNAs associated with skeletal metastatic disease in a preclinical model of lung cancer bone metastasis. We assessed the validity of these miRNAs as reliable serum biochemical markers to monitor the extent of disease and response to treatment in comparison to imaging techniques and standard biochemical markers of bone turnover. Using a murine model of human lung cancer bone metastasis after zoledronic acid (ZA) treatment, PINP (procollagen I amino-terminal propeptide) was the only marker that exhibited a strong correlation with osteolytic lesions and tumor burden at early and late stages of bone colonization. In contrast, BGP (osteocalcin) and CTX (carboxyterminal telopeptide) demonstrated a strong correlation only at late stages. We performed qPCR based screening of a panel of 380 human miRNAs and quantified bone metastatic burden using micro-CT scans, X-rays and bioluminescence imaging. Interestingly, levels of miR-326 strongly associated with tumor burden and PINP in vehicle-treated animals, whereas no association was found in ZA-treated animals. Only miR-193 was associated with biochemical markers PINP, BGP and CTX in ZA-treated animals. Consistently, miR-326 and PINP demonstrated a strong correlation with tumor burden. Our findings, taken together, indicate that miR-326 could potentially serve as a novel biochemical marker for monitoring bone metastatic progression. 相似文献
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Hantaan virus was discovered in Korea during the 1970s while other similar viruses were later reported in Asia and Europe. There was no information about hantavirus human infection in the Americas until 1993 when an outbreak was described in the United States. This event promoted new studies to find hantaviruses in the Americas. At first, many studies were conducted in Brazil, Argentina, Chile, Uruguay and Paraguay, while other Latin American countries began to report the presence of these agents towards the end of the 20th century. More than 30 hantaviruses have been reported in the Western Hemisphere with more frequent cases registered in the southern cone (Argentina, Chile, Uruguay, Paraguay, Bolivia and Brazil). However there was an important outbreak in 2000 in Panama and some rare events have been described in Peru, Venezuela and French Guiana. Since hantaviruses have only recently emerged as a potential threat in the tropical zones of the Americas, this review compiles recent hantavirus reports in Central America, the Caribbean islands and the northern region of South America. These studies have generated the discovery of new hantaviruses and could help to anticipate the presentation of possible future outbreaks in the region. 相似文献