Non-structural carbohydrate dynamics and growth in tomato plants grown at fluctuating light and temperature.

Fluctuations in light intensity and temperature lead to periods of asynchrony between carbon (C) supply by photosynthesis and C demand by the plant organs. Storage and remobilization of non-structural carbohydrates (NSC) are important processes that allow plants to buffer these fluctuations. We aimed to test the hypothesis that C storage and remobilization can buffer the effects of temperature and light fluctuations on growth of tomato plants. Tomato plants were grown at temperature amplitudes of 3 or 10°C (deviation around the mean of 22°C) combined with integration periods (IP) of 2 or 10 days. Temperature and light were applied in Phase (high temperature simultaneously with high light intensity, (400 µmol m-2 s-1), low temperature simultaneously with low light intensity (200 µmol m-2 s-1) or in Antiphase (high temperature with low light intensity, low temperature with high light intensity). A control treatment with constant temperature (22°C) and a constant light intensity (300 µmol m-2 s-1) was also applied. After 20 days all treatments had received the same temperature and light integral. Differences in final structural dry weight were relatively small, while NSC concentrations were highly dynamic and followed changes of light and temperature (a positive correlation with decreasing temperature and increasing light intensity). High temperature and low light intensity lead to depletion of the NSC pool, but NSC level never dropped below 8% of the plant weight and this fraction was not mobilizable. Our results suggest that growing plants under fluctuating conditions do not necessarily have detrimental effects on plant growth and may improve biomass production in plants. These findings highlight the importance in the NSC pool dynamics to buffer fluctuations of light and temperature on plant structural growth.

Eating behaviors associated with weight gain among university students worldwide and treatment interventions: A systematic review.

Introduction: Emerging adulthood has been described as a period of risk for body weight gain. Several studies have indicated that the positive or negative health behaviors established during this stage, tend to prevail the rest of life. However, there are discrepancies in published studies on weight change in freshmen and there are disagreements on weight gain predictors. The present study reviewed the literature with the aim of knowing the eating behaviors associated with weight gain in university students. Method: A systematic search was conducted in three databases according to the PRISMA method during the months of February to November 2020. Results: 20 articles were included in the review. The main behaviors associated with weight gain were the consumption of sugary drinks, alcohol consumption, low consumption of vegetables and fruits, frequent self-consumption, eating unhealthy and low levels of food regulation.

[Ovarian reserve and premature ovarian failure in girls and adolescents after hematopoietic stem cell transplantation]. / Reserva ovárica y falla ovárica prematura en niñas y adolescentes postrasplante de progenitores hematopoyéticos.

INTRODUCTION: The increased survival of children and adolescents after Stem Cell Transplantation (SCT) has allowed us to gain a better understanding of the late effects that this procedure might have. OBJECTIVE: to measure ovarian function and reserve after SCT. PATIENTS AND METHOD: A descriptive, observatio nal, and cross-sectional study of girls and adolescents with SCT between 1999 and 2011. External gynecologic examination, hormone tests, and abdominal gynecologic ultrasound were performed, observing pubertal development pre-SCT. The following data from the clinical record were recorded: baseline pathology, type of conditioning, use of radiotherapy in conditioning, age at the time of SCT, and history of acute or chronic graft-versus-host disease (GVHD). Hormonal tests included follicle- stimulating hormone (FSH), luteinizing hormone (LH), estradiol, prolactin (PRL), thyroid-stimula ting hormone (TSH), free thyroxine, total testosterone, sex hormone-binding globulin (SHBG), and anti-Müllerian hormone (AMH). Statistical analysis included the chi-square or Fisher's Exact test with a p-value < 0.05. RESULTS: 41 patients were evaluated. The median age at the time of SCT was 6.8 years (1.5-14.1) and the median age at evaluation was 14.8 years (range: 4-25.4 years). 93% of the transplants were in patients with oncological disease and with myeloablative conditioning regimens. All patients presented decreased ovarian reserve, and 72% showed Premature Ovarian Failure (POF). CONCLUSIONS: All patients had decreased ovarian reserve and most of them had a high prevalence of POF. Before SCT, a gynecological evaluation and subsequent follow-up for hormone monitoring and initiation of hormone replacement are essential.

Description of a new species of emGlassella/em Campos amp; Wicksten, 1997 from a coastal lagoon, SE Gulf of California (Crustacea, Decapoda, Pinnotheridae).

A new a species of pinnotherid crab in the eastern Pacific coasts is presented. Twenty males and 21 females of small crabs were collected from burrows, presumably from ghost shrimp (Neotrypaea spp.), in sand-mud substrata from the Santa María-La Reforma coastal lagoon, SE Gulf of California. The new species was assigned to the genus Glassella because its morphological characteristics clearly match the amended diagnosis of the genus Glassella by Palacios Theil and Felder (2020) and Felder Palacios Theil (2020), including the presence of a gonopodal plate (GP) inserted in the internal part of the male pleon, similar to that described for most of the species currently grouped into the genus Glassella. The new species is similar to G. miamiensis (McDermott, 2014) from western Atlantic, but it can be distinguished from this and the rest of the species of Glassella by differences in carapace margins and ridges, male pleon outline, and the shape of the GP.

Efectos de la actividad física sobre el consumo y selección de alimento en ratas que fueron expuestas a restricción alimentaria durante la gestación / Effects of physical activity on the consumption and selection of food in rats that were exposed to food restriction during pregnancy

Las alteraciones durante la vida prenatal tienen diversos efectos en los organismos. La restricción alimentaria materna ocasiona modificaciones en la conducta alimentaria como hiperfagia y su exacerbación ante la exposición a una dieta hiperlipídica. La evidencia experimental indica que aun cuando existe una preferencia por los alimentos altos en grasa, cuando las ratas realizan actividad física, esta preferencia disminuye o se elimina. Objetivo: evaluar el efecto de la restricción alimentaria materna sobre el consumo de una dieta suplementada con nuez pecana y cómo influye la actividad física. El experimento incluyó 22 ratas, 11 del grupo experimental y 11 del grupo control. De los cuales 6 realizaron actividad y 5 permanecieron sedentarias en cada grupo (machos y hembras). El experimento duró 114 días, de los cuales 42 días tuvieron disponible la rueda de actividad. Los resultados mostraron que la restricción alimentaria materna no modificó el comportamiento alimentario, sin embargo, cuando incrementaron la actividad por la disponibilidad de la rueda de actividad, los sujetos experimentales aumentaron su consumo de nuez pecana. Los resultados se consideran contradictorios con respecto a la literatura, ya que muestran ausencia de hiperfagia e incremento en el consumo a la par del incremento en actividad física.

Alterations during prenatal life have various effects on organisms. Maternal food restriction causes changes in feeding behavior such as hyperphagia and its exacerbation when exposed to a hyperlipidic diet. Experimental evidence indicates that even when there is a preference for high-fat foods, when rats do physical activity, this preference decreases or is eliminated. Objective: to evaluate the effect of maternal dietary restriction on the consumption of a diet supplemented with pecan nuts and how physical activity influences this relationship. The experiment included 22 rats, 11 experimental and 11 controls. Of these, 6 performed physical activity and 5 remained sedentary in each group (males and females). The experiment lasted 114 days; the activity wheel was available on 42 days. The results showed that maternal food restriction did not modify eating behavior, however, when rats increased physical activity, experimental subjects increased their consumption of pecan nuts. The results are contradictory with respect to the literature, as they show an absence of hyperphagia and an increase in consumption along with an increase in physical activity.

Asthma in Mexican school-age children is not associated with passive smoking or obesity.

BACKGROUND: Asthma has increased in various regions of the world. The factors associated with the growth in prevalence are still to be determined. OBJECTIVE: To evaluate the degree of association of the prevalence of asthma with passive smoking and obesity in school-children in western Mexico. METHODS: A population-based cross-section analytic study. A stratified random sample of 740 primary school pupils of between 6 and 12 years of age was chosen. Asthma, passive smoking and a background of allergic diseases were identified by means of a standardized questionnaire filled out by the parents of the participants. Obesity was identified by means of the body mass index. Proportional sections of population were estimated and the degree of association between asthma (dependent variable) and the independent variables was evaluated by means of multivariate logistic regression. RESULTS: THE FOLLOWING FACTORS OF PREVALENCE WERE FOUND: asthma 8.1%; obesity 19.9%; background of smoking in the father 6.7% and in the mother 13.3%. There was no significant association to be found with asthma in either passive smoking where one of the parents smoked (p = 0.39) or in obesity (p = 0.09). On the other hand, the background of allergic diseases in the mother showed statistically significant association with asthma in the boys (odds ratio = 3.5, 95% confidence interval 1.4 to 8.59), but not in the girls. CONCLUSION: With the exception of the maternal background of allergy, neither obesity nor passive smoking are factors associated with asthma in Mexican children.

Evaluation of metabolic syndrome after hematopoietic stem cell transplantation in children and adolescents.

BACKGROUND: To determine the prevalence, characteristics, and risk factors associated with metabolic syndrome (MS) in patients undergoing hematopoietic stem cell transplantation (HSCT) in the Chilean National Program. PROCEDURES: Descriptive and cross-sectional study including 69 patients was conducted. Body mass index, pubertal development, waist circumference, arterial pressure (AP), and triglycerides, HDL-cholesterol, and glucose levels were recorded at the time of study entry. The National Cholesterol Education Program (Adult Treatment Panel III, as modified by the American Heart Association) criteria are often used to diagnose MS in adults; however, for children and adolescents we followed criteria according to De Ferranti and American Diabetes Association. Statistical analyses were performed with a chi-square test or Fisher's exact test according to sample size. RESULTS: Sixty-nine patients were studied. The median age at the time of diagnosis was 12.9 years, and the median time of follow-up post-transplant was 4 years. Forty-three patients were males, 54 patients had malignant diseases, and 59 patients received allogeneic transplants. Of the 69 patients, 32% had MS; the most common MS features were abdominal obesity (73%), hypertriglyceridemia (91%), and a low HDL-cholesterol level (96%). The most significant risk factor for MS was corticosteroid therapy use pre- (P < 0.03) and post-HSCT (P < 0.03), obesity and overweight associated with MS (P < 0.001). No patient developed cardiovascular complications. CONCLUSIONS: The prevalence of MS was 32%, which was significantly higher than in a healthy pediatric population. We recommend prolonged follow-up for transplant recipients, coupled with enforcement of preventive measures, such as early diagnosis and encouragement of a healthy lifestyle.

[Prevalence and associated factors to allergic rhinitis in school children of ciudad Guzmán, Mexico]. / Prevalencia y factores asociados a la rinitis alérgica en escolares de ciudad Guzmán, México.

INTRODUCTION: A considerable amount of risk factors have been proposed to explain the increase in the frequency of allergic rhinitis; some of them are atopy, cigarette smoking of parents, birthweight, type of feeding at the time of birth and the nutritional state, but the results have been inconsistent. The present study seeks to investigate the role played by these risk factors in the development of allergic rhinitis in a sample of school children. MATERIAL AND METHODS: The data was gathered from 6-12 year old school children. Their parents filled out the questionary which was validated by means of the International Study on Asthma and Allergies in Childhood. Further questioning included background regarding atopy, breastfeeding, birthweight and type of delivery; weight and height were used to calculate the body mass index. RESULTS: Among 740 children in this study, the frequency of allergic rhinitis was 5.5%; the past history of allergic disease in the father (OR = 3.1; CI 95%, 1.2-8.1, p = 0.018) or in the mother (OR = 3.2; CI 95%, 1.5-6.6, p = 0.002) was importantly associated to the development of allergic rhinitis. We did not find association with the rest of the variables under study. CONCLUSION: These results indicate that the prevalence of allergic rhinitis is similar to the one reported in previous studies. The only risk factor associated to allergic rhinitis was the past history of atopic disease in their parents.

[Atopic dermatitis in scholar children from Ciudad Guzman, Mexico. Prevalence and related factors]. / Dermatitis atópica en niños escolares de Ciudad Guzmán, México. Prevalencia y factores asociados.

BACKGROUND: Atopic dermatitis is an ever more frequent disease in children; its etiology is unknown, although a genetic predisposition along with environment factors could be the origin. OBJECTIVE: To determine the prevalence of atopic dermatitis among school-children and the main associated risk factors. PATIENTS AND METHODS: A randomized, stratified and conglomerated sample of 6 to 12 year-old school-children was obtained. Their parents answered the main ISAAC questionnaire, to which some variables were added, such as family and hereditary history, tobacco smoking exposure and nutritional condition according to the body mass index as associated risk factors. RESULTS: We found a prevalence of 3% for atopic dermatitis, and the presence of dermatitis symptoms during the last twelve months was found in 6.8% of the cases. Multivariate analysis demonstrated an elevated risk for atopic dermatitis in children of mothers with any type of allergic disease (OR 2.75, CI 95% 1.09 to 6.92, p = 0.031). CONCLUSIONS: The frequency of atopic dermatitis as well as that of the symptoms was low, similar to previous reports conducted in Mexico. Maternal atopy was the only factor associated with atopic dermatitis.

Cytomegalovirus infection in children undergoing hematopoietic stem cell transplantation in Chile.

BACKGROUND: Cytomegalovirus (CMV) infection remains as an important cause of morbidity and mortality in children undergoing hematopoietic stem cell transplantation (HSCT). Our aim was to assess the incidence, risk factors, and outcome related to CMV infection in children after HSCT in a developing country. METHODS: From October 1, 1999, to December 31, 2005, we prospectively studied all patients admitted to the HSCT unit at Hospital Luis Calvo Mackenna in Santiago, Chile. Serologic studies before transplantation and weekly CMV infection surveillance (antigenemia or quantitative PCR) were routinely obtained. Patients with positive antigenemia or quantitative PCR received pre-emptive therapy with ganciclovir, and cases of unfavorable clinical evolution, persistent positive antigenemia, or quantitative PCR after 14 days of ganciclovir were treated with foscarnet. RESULTS: Ninety-seven patients received HSCT. Their median age was 8 years (range, 3 months to 24 years) and their overall survival was 67%. CMV reactivation was diagnosed in 26 patients. Of these, three developed CMV disease (two interstitial pneumonia, one hemorrhagic cystitis). One of the patients with pneumonia died. Risk factors identified were pre-transplant serologic status (positive recipient), acute and chronic graft versus host disease (GvHD), GvHD prophylaxis, and treatment with antithymocyte globulin. CONCLUSIONS: The rate and prognosis of CMV infection among children treated at our HSCT unit is similar to those reported from industrialized countries. These findings reflect adequate prevention and management of CMV infection within our program.

Pain from copper intrauterine device insertion: randomized trial of prophylactic ibuprofen.

OBJECTIVES: This study was undertaken to determine whether 400 mg of prophylactic ibuprofen can alleviate pain from insertion of an intrauterine device (IUD) and to measure level of pain with improved techniques. STUDY DESIGN: We conducted a randomized, double-blind, placebo-controlled trial of 2019 first-time IUD users: 1008 women received placebo and 1011 women received 400 mg of ibuprofen. Participants took the single tablet at least 45 minutes before IUD insertion. Immediately after insertion, participants recorded level of pain by using a 10-cm visual analog scale, with the value of 10 meaning "worst imaginable pain." RESULTS: Median level of pain was 1.0 for both ibuprofen and placebo participants; rank test statistics confirmed no difference. Some subgroups of women experienced higher pain (eg, nulliparous women), but ibuprofen still had no important impact on level of pain. CONCLUSION: Even among first-time users, pain from IUD insertion is generally low. Prophylactic ibuprofen as used in this protocol does not reduce IUD insertion pain.

Preventing copper intrauterine device removals due to side effects among first-time users: randomized trial to study the effect of prophylactic ibuprofen.

BACKGROUND: Increased menstrual bleeding and pain are the primary side effects that lead to early removal of the copper intrauterine device (IUD). Ibuprofen and other non-steroidal anti-inflammatory drugs (NSAIDs) are proven treatments for such IUD-induced problems, but their effect on early IUD removal is unknown. METHODS: A total of 2019 first-time IUD users were recruited in Chile for this double-blind, randomized, placebo-controlled trial. Half of the participants were given ibuprofen and instructions to take 1200 mg daily during menses (for up to 5 days each cycle) for the first 6 months of IUD use. The other half were asked to take an identical appearing placebo in the same manner. The primary outcome was IUD removal within 12 months of insertion. RESULTS: A total of 1011 and 1008 women were randomly assigned to ibuprofen and placebo, respectively. During 12 months of observation, 190 had the device removed because of dysmenorrhoea and/or increased menstrual bleeding: 85 in the placebo group and 105 in the ibuprofen group. For ibuprofen users, the hazard ratio for removal for these IUD-induced side effects was 1.0 and 1.2 at 6 and 12 months, respectively (both not significant). CONCLUSION: Although increased menstrual bleeding and pain are common reasons for early IUD removal, prophylactic use of ibuprofen, at the dosage used here, does not reduce removal rates.

Extended use of a progesterone-releasing vaginal ring in nursing women: a phase II clinical trial.

AIM: This study evaluates the performance of extended use of a progesterone (P)-releasing vaginal ring (PVR) in nursing women. METHOD: An open-label, noncomparative study on the safety and contraceptive efficacy of PVR replaced every 4 months of use (instead of 3 months) in 192 PVR acceptors. PVR use was initiated at day 59+/-2 (mean+/-SD) postpartum and continued until weaning or completing the use of three PVRs. RESULTS: Plasma P levels attained with the ring decreased from 17+/-1 to 14+/-1 nmol/L (mean+/-SE) from the third to the fourth month of use. These levels are still over the critical level of 10 nmol/L required for contraceptive protection. One pregnancy occurred in the third month of use of the second ring in 1998 woman-months of exposure. Extended use of the ring did not appear to affect breast-feeding performance or the rate of infant growth, and lactational amenorrhea was prolonged. No differences in the characteristics of bleeding between the third and fourth month of ring use were observed. CONCLUSION: The results indicate that use of the PVR for 4 months represents a safe and effective contraceptive for nursing women.

Health and growth of infants breastfed by Norplant contraceptive implants users: a six-year follow-up study.

The objective of the study was to evaluate safety to infants whose mothers used Norplant levonorgestrel implants during breastfeeding. A nonrandomized clinical trial design was used. Participants were 220 and 222 healthy breastfed infants of mothers initiating use of Norplant or T-Cu IUD, respectively, at 55 days to 60 days postpartum. Infants were followed from birth through age 6 years. Breastfeeding pattern, infant growth, and disease events were recorded monthly in the first year, three-monthly in the second, and annually thereafter. Most mothers continued use of Norplant (96.4%) and T-Cu (94.1%) during lactation, and 2140 months of infant exposure to levonorgestrel were accumulated. Breastfeeding pattern and infants growth, from admission through age 6 years, were similar in both groups. In the first year, breastfed infants in the Norplant group had higher incidence rates (p < 0.05) of mild episodes of respiratory infections (adjusted RR 1.17, CI 1.08-1.27), skin conditions (adjusted RR 1.46, CI 1.20-1.79), and eye infections (unadjusted RR 1.49, CI 1.03-2.18) than the control group. Later on, a higher proportion of infants in the T-Cu group showed neurological conditions. Although breastfeeding patterns and infant growth is not affected by Norplant use during lactation, the effect on infants' health of steroidal contraception should be further evaluated.