T4 Concentrations Research Articles

Acute moderate normobaric hypoxia does not modify circulating thyroid hormone concentrations induced by 1 h of head-out cold-water immersion.

This study tested the hypothesis that acute moderate normobaric hypoxia augments circulating thyroid hormone concentrations during and following 1 h of cold head-out water immersion (HOWI), compared with when cold HOWI is completed during normobaric normoxia. In a randomized crossover single-blind design, 12 healthy adults (27 ± 2 yr, 2 women) completed 1 h of cold (22.0 ± 0.1°C) HOWI breathing either normobaric normoxia ([Formula: see text] = 0.21) or normobaric hypoxia ([Formula: see text] = 0.14). Free and total thyroxine (T3) and triiodothyronine (T4), and thyroid-stimulating hormone (TSH) concentrations were measured in venous blood samples obtained before (baseline), during (15-, 30-, and 60 min), and 15 min following HOWI (post-), and were corrected for changes in plasma volume. Arterial oxyhemoglobin saturation and core (rectal) temperature were measured continuously. Arterial oxyhemoglobin saturation was lower during hypoxia (90 ± 3%) compared with normoxia (98 ± 1%, P < 0.001). Core temperature fell from baseline (normoxia: 37.2 ± 0.4°C, hypoxia: 37.2 ± 0.4°C) to post-cold HOWI (normoxia: 36.4 ± 0.5°C, hypoxia: 36.3 ± 0.5°C, P < 0.001) in both conditions but did not change differently between conditions (condition × time: P = 0.552). Circulating TSH, total T3, free T4, total T3, and free T4 concentrations demonstrated significant main effects of time (all P ≤ 0.024), but these changes did not differ between normoxic and hypoxic conditions (condition × time: all P ≥ 0.163). These data indicate that acute moderate normobaric hypoxia does not modify the circulating thyroid hormone response during 1 h of cold HOWI.NEW & NOTEWORTHY Acute head-out cold (22°C) water immersion (HOWI) decreased core temperature and increased thermogenesis. This thermogenic response was paralleled by the activation of the hypothalamic-pituitary-thyroid axis, as evidenced by changes in thyroid hormones. However, cold HOWI in combination with moderate normobaric hypoxia did not modify the thermogenic nor the circulating thyroid hormone response. This finding suggests that hypoxia-induced alterations in thyroid hormone concentrations are unlikely to acutely contribute to adaptations resulting from repeated cold-water exposures.

Variations in thyroid hormone levels in endangered St. Lawrence Estuary belugas: Potential linkage with stress and organohalogen contaminant exposure

The St. Lawrence Estuary (SLE) beluga (Delphinapterus leucas) population is highly exposed to an array of contaminants that were identified as one of the causes to the non-recovery of this endangered and declining population. In the last decade, an increasing number of parturition-associated complications and calf mortality has been reported in this population. It was suggested that elevated exposure to organohalogens (e.g., the halogenated flame retardants polybrominated diphenyl ethers [PBDEs]) and stress could play a role in this phenomenon by perturbing thyroid hormones. The objective of this study was to investigate the impact of concentrations of organohalogen contaminants and stress (cortisol levels) on thyroid hormone variations in adult male and female SLE belugas. Because plasma could not be collected in SLE belugas for ethical reasons, skin biopsy (n = 40) was used as a less-invasive alternative matrix to determine organohalogens (PBDEs and other halogenated flame retardants, polychlorinated biphenyls, and organochlorine pesticides), cortisol, and thyroid hormones (triiodothyronine [T3] and thyroxine [T4]), and their metabolites reverse T3 and 3,5-diiodothyronine [3,5-T2]). Cortisol and thyroid hormones were analyzed by ultra-performance liquid chromatography-multiple reactions monitoring mass spectrometry (UPLC-MRM/MS). This method was compared using skin and plasma samples obtained from Arctic belugas. Comparisons of linear models showed that cortisol was a weak predictor for T4, rT3 and 3,5-T2. Specifically, there was a weak significant negative association between T4 and cortisol levels. Moreover, in male SLE belugas, a weak significant positive association was found between T3 and Σ34PBDE concentrations in skin. Our findings suggest that stress (i.e., elevated skin cortisol levels) along with organohalogen exposure (mainly PBDEs) may be associated with thyroid hormone level perturbations in skin of cetaceans.

Effects of Palm (Elaeis Guineensis) Oil on Performance, Thermotolerance, and Welfare of Broiler Chickens in Heat Stress Condition

Heat stress negatively affects the broiler chickens’ productivity and well-being. This study was carried out to assess the effect of dietary palm oil inclusion on the growth performance, thermotolerance, biochemical parameters, and welfare of broiler chickens raised in tropical climates. A total of 500 broiler chickens aged 15 days were divided into four treatments, each consisting of five replicates with 25 chickens per replicate in a randomized design. The control group was fed a standard diet without palm oil (T), and the remaining diets contained palm oil at the inclusion levels of 1% (P1), 2% (P2), and 3% (P3). During the 4 weeks of experimentation, daily temperature and relative humidity in the poultry house were measured by thermo-hygrometers, and growth performance was weekly recorded. At 45 days old, six broiler chickens were slaughtered with measurements taken for carcass compositions and intestinal length. At 42 days of age, blood samples were collected for the Triiodothyronine (T3) and Thyroxine (T4) hormones, biochemical profiles, and Heterophil: lymphocyte (H/L) ratio assessment at the Regional Center of Excellence on Avian Sciences. Gait abnormality and litter quality were assessed at 38 days of age. The results indicated that the incorporation of 1% palm oil improved the growth performance of chickens compared to other groups. Similarly, the concentrations of T4 and T3 were higher in the 1% palm oil group. Triglycerides and total protein concentrations were higher in the broiler chickens of the control group, compared to other treatment groups. The dropping weight and gait score decreased with the increasing rate of palm oil. The results suggest that palm oil can be a beneficial dietary supplement for broiler chickens, particularly under heat-stress conditions. The incorporation of 1% palm oil contributes to the improvement of growth performance and the well-being of broiler chickens in tropical climates. However, it is crucial to consider the appropriate level of palm oil inclusion, as higher levels may have adverse effects, such as increased mortality. Keywords: Energy, Feeding strategies, Heat stress, Palm oil, Welfare

Low thyroxine serves as an upstream regulator of ecophysiological adaptations in Ansell's mole-rats.

About 10% of all rodent species have evolved a subterranean way of life, although life in subterranean burrows is associated with harsh environmental conditions that would be lethal to most animals living above ground. Two key adaptations for survival in subterranean habitats are low resting metabolic rate (RMR) and core body temperature (Tb). However, the upstream regulation of these traits was unknown thus far. Previously, we have reported exceptionally low concentrations of the thyroid hormone (TH) thyroxine (T4), and peculiarities in TH regulating mechanisms in two African mole-rat species, the naked mole-rat and the Ansell's mole-rat. In the present study, we treated Ansell's mole-rats with T4 for four weeks and analyzed treatment effects on the tissue and whole organism level with focus on metabolism and thermoregulation. We found RMR to be upregulated by T4 treatment but not to the extent that was expected based on serum T4 concentrations. Our data point towards an extraordinary capability of Ansell's mole-rats to effectively downregulate TH signaling at tissue level despite very high serum TH concentrations, which most likely explains the observed effects on RMR. On the other hand, body weight was decreased in T4-treated animals and Tb was upregulated by T4 treatment. Moreover, we found indications of the hypothalamus-pituitary-adrenal axis potentially influencing the treatment effects. Taken together, we provide the first experimental evidence that the low serum T4 concentrations of Ansell's mole-rats serve as an upstream regulator of low RMR and Tb. Thus, our study contributes to a better understanding of the ecophysiological evolution of the subterranean lifestyle in African mole-rats.

Takotsubo syndrome outcomes predicted by thyroid hormone signature: insights from cluster analysis of a multicentre registry

Recently, abnormal thyroid function was shown to be common in patients with Takotsubo syndrome (TTS), being classified into "endocrine-type" and "stress-type" responses. The aim of this study was to investigate the association between thyroid homeostasis and TTS in a larger international registry. In total 288 patients with TTS were enrolled through the GEIST multicentre registry from Germany, Italy and Spain. Thyrotropin (TSH), free T4 (FT4) and free T3 (FT3) concentrations were analysed at admission. Data were collected both retrospectively and prospectively from 2017 onwards. Primary endpoints included in-hospital and all-cause fatality, determined by cluster analysis using an unsupervised machine learning algorithm (k-medoids). Three clusters were identified, classifying TTS with low (TSLT), high (TSHT) and normal (TSNT) thyroid output, based on TSH and FT4 levels in relation to the median thyroid's secretory capacity (SPINA-GT). Although TSH and FT4 concentrations were similar among survivors and non-survivors, these clusters were significantly associated with patient outcomes. In the longitudinal Kaplan-Meier analysis including in- and out-of-hospital survival, the prognosis related to concentrations of TSH, FT4, and FT3 as well as SPINA-GT, deiodinase activity (SPINA-GD) and clusters. Patients in the TSHT cluster and with cardiogenic shock had a lower initial left ventricular ejection fraction (LVEF). This study suggests that thyroid hormones may impact the evolution and prognosis of TTS. The findings indicate that thyroid-derived biomarkers may help identify high-risk patients and pave the way for novel personalized and preventive therapeutic options. This research was not funded by any public, commercial, or not-for-profit agencies.

Chronic Kidney Disease affects Thyroid Hormones

Kidney disease is one of the causes of death in many countries around the world. This study found that chronic kidney disease affects thyroid hormone formation, release, and storage. The results show a decrease in T3 and T4 thyroid hormones and an increase in TSH hormone in both sexes and people of different ages. The research aims to study the effect of chronic kidney disease on the thyroid gland’s activity and its deficiency’s effect on health ailments. Results showed a significant decrease in T3 concentration in patients at the probability level (p ≤ 0.05) (0.8±0.1) compared with the control group (1.0±0.1). Additionally, a significant decrease in T4 concentration at the probability level (p ≤ 0.05), (6.8±1.5) compared with the control group (8.7±0.9) and a significant increase in TSH concentration at the probability level (p ≤ 0.05), (4.8±0.6) compared with the control group (1.2±0.5). The CDK affects thyroid hormones; low T3 and T4 are the most common thyroid dysfunction. High TSH, enlarged thyroid gland, hypothyroidism, thyroid dysfunction. Keywords: CKD, Thyroid Hormones, Thyroid dysfunction.

Chronic Kidney Disease affects Thyroid Hormones

Kidney disease is one of the causes of death in many countries around the world. This study found that chronic kidney disease affects thyroid hormone formation, release, and storage. The results show a decrease in T3 and T4 thyroid hormones and an increase in TSH hormone in both sexes and people of different ages. The research aims to study the effect of chronic kidney disease on the thyroid gland’s activity and its deficiency’s effect on health ailments. Results showed a significant decrease in T3 concentration in patients at the probability level (p ≤ 0.05) (0.8±0.1) compared with the control group (1.0±0.1). Additionally, a significant decrease in T4 concentration at the probability level (p ≤ 0.05), (6.8±1.5) compared with the control group (8.7±0.9) and a significant increase in TSH concentration at the probability level (p ≤ 0.05), (4.8±0.6) compared with the control group (1.2±0.5). The CDK affects thyroid hormones; low T3 and T4 are the most common thyroid dysfunction. High TSH, enlarged thyroid gland, hypothyroidism, thyroid dysfunction. Keywords: CKD, Thyroid Hormones, Thyroid dysfunction.

Evaluation of a novel, sensitive thyroid-stimulating hormone assay as a diagnostic test for thyroid disease in cats.

Clinicians commonly use thyroid-stimulating hormone (TSH) concentrations to diagnose thyroid disorders in humans and dogs. In cats, canine TSH chemiluminescent immunoassays (CLIA) assays are commonly used to measure TSH, but these TSH-CLIAs cannot measure low TSH concentrations (< 0.03 ng/mL) and therefore cannot distinguish between low-normal concentrations and truly low TSH concentrations (characteristic of hyperthyroidism). Our aim was to evaluate a novel TSH assay based on bulk acoustic wave (BAW) technology that has lower functional sensitivity (0.008 ng/mL) than TSH-CLIAs. 169 untreated hyperthyroid cats, 53 cats treated with radioiodine (131I), 12 cats with chronic kidney disease (CKD), and 78 clinically healthy cats. Serum concentrations of T4, TSH-CLIA, and TSH-BAW were measured in all cats. Untreated hyperthyroid cats were divided into 4 severity groups (subclinical, mild, moderate, and severe), whereas 131I-treated cats were divided into euthyroid and hypothyroid groups. Test sensitivity, specificity, and positive predictive value for identifying hyperthyroidism were higher for TSH-BAW (90.5%, 98.9%, and 86.9%) than TSH-CLIA (79.9%, 76.7%, and 21.7%; P < .001). Test sensitivity for identifying 131I-induced hypothyroidism was only 45.5% for T4 versus 100.0% for both TSH-CLIA and TSH-BAW (P = .03), whereas TSH-BAW had a higher positive predictive value (100%) than did either TSH-CLIA (81.2%) or T4 (71.9%). Serum TSH-BAW alone or together with T4 is a highly sensitive and specific diagnostic test for evaluating feline hyperthyroidism and iatrogenic hypothyroidism. Finding low serum TSH-BAW concentrations is most useful for diagnosing subclinical and mild hyperthyroidism, in which serum T4 remains within or only slightly above the reference interval.

Hormonal profile changes under the influence of environmental factors in children residing in the Aral environmental disaster region

BACKGROUND: Since the mid 20th century, the Southern Aral Sea Region is notorious as a region of ecological disaster, where anthropogenic influence led to the desiccation of the Aral Sea. Aridization of these territories is the cause of accumulation of endocrine disrupting chemicals — pesticides and toxic metals in soil and water.&#x0D; AIM: The aim of this study was to assess the changes in hormonal profile under the influence of environmental factors in prepubertal children living at different distances from the epicenter of the Aral ecological disaster.&#x0D; MATERIALS AND METHODS: The study included 58 male children aged 11–13 years. All children from birth lived in two regions of the Aral Sea Region and were divided into two groups depending on their place of residence. The group “North” (unfavorable conditions) consisted of 27 children from Muynak, Kungrad, Karauzyak, Takhtakupyr districts. The “Nukus” group (relatively favorable conditions) included 31 volunteers from Nukus city. All children were determined the concentration of IGF-1 — Insulin-like growth factor 1, GH — growth gormone, TT — total testosterone, E2 — estradiol, FSH — follicle-stimulating hormone, LH — luteinizing hormone, TSH — thyroid-stimulating hormone, TT3 — total triiodothyronine in blood sample. The statistical significance of the differences of the mentioned hormones in children from the “North” and “Nukus” groups was checked using the Mann–Whitney test.&#x0D; RESULTS: This analysis revealed statistically significantly higher values of TT, FSH and LH in children from the “Nukus” group compared to their peers from the “North” group. The concentrations of IGF-1, GH, E2, TTG and T3 in blood plasma in volunteers from both groups were not statistically significantly different.&#x0D; CONCLUSIONS: The environment of the Aral ecological disaster region with increased content of organochlorine compounds, pesticides and heavy metals changes the endocrine status in local prepubertal children. This is expressed in a moderate decrease in the activity of androgens (but not estrogens) and gonadotropic hormones. This research work can be considered as a pilot study, which determines the need for further monitoring of endocrine disorders in children and adults living in negative environmental conditions.

Multi-trait analysis characterizes the genetics of thyroid function and identifies causal associations with clinical implications

To date only a fraction of the genetic footprint of thyroid function has been clarified. We report a genome-wide association study meta-analysis of thyroid function in up to 271,040 individuals of European ancestry, including reference range thyrotropin (TSH), free thyroxine (FT4), free and total triiodothyronine (T3), proxies for metabolism (T3/FT4 ratio) as well as dichotomized high and low TSH levels. We revealed 259 independent significant associations for TSH (61% novel), 85 for FT4 (67% novel), and 62 novel signals for the T3 related traits. The loci explained 14.1%, 6.0%, 9.5% and 1.1% of the total variation in TSH, FT4, total T3 and free T3 concentrations, respectively. Genetic correlations indicate that TSH associated loci reflect the thyroid function determined by free T3, whereas the FT4 associations represent the thyroid hormone metabolism. Polygenic risk score and Mendelian randomization analyses showed the effects of genetically determined variation in thyroid function on various clinical outcomes, including cardiovascular risk factors and diseases, autoimmune diseases, and cancer. In conclusion, our results improve the understanding of thyroid hormone physiology and highlight the pleiotropic effects of thyroid function on various diseases.

Interactive effects of dietary protein and nano-chitosan on growth performance, immune response, and histological aspects of lymphoid organs in broiler chickens

A feeding trial was conducted to assess the effect of partial replacement of dietary soybean meal by three plant protein sources: coconut, rocket seed, and black cumin meals with their combination in the presence or absence of nano-chitosan (NCH) on growth performance and immune response in broiler chickens. Five starter and grower diets were formulated and used from 1 to 42 days of age. The NCH was added to starter and grower diets at 1.0 g/kg. Five-hundred-fifty-day-old Arbor Acres Plus broiler chicks were randomly divided into ten treatments with five equal replications. Final body weight (FBW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR), and blood plasma parameters were investigated. Histological aspects of lymphoid organs (thymus: T, bursa of Fabricius: B, and spleen: S) were characterized. Apart from added NCH, the FBW, BWG, and FCR of broilers fed the diets containing the tested plant proteins were significantly superior to the control ones. However, FI of birds fed the diets containing CM alone or combined with RSM plus BCM was significantly reduced. All experimental broilers displayed high plasma levels of IgG compared with the control group. There were significant increases in plasma concentrations of IgM, IgA, and T4 for groups that fed the diets containing RSM, BCM, and mixture of CM, RSM, and BCM compared with their controls. The T3 levels of broilers fed the tested plant proteins were significantly increased compared with the controls. Aside from plant protein source, broilers fed the NCH-enriched diets achieved significant increases in levels of IgM, TAC, and FSH and activities of CAT and SOD but reduced the MDA level compared with control. The interactions between plant protein source and added nano-chitosan were not interrelated. Furthermore, CM, RSM, and BCM can be used as complementary dietary proteins singly or combined with NCH with no adverse effects on growth performance. Addition of NCH molecules has a positive effect on live body weight and increases feed intake compared with control chicks.Graphical

Thyroid Hormone Metabolites Quantified in Pup and Adult Rat Cerebellum, Cortex and Whole-Brain Samples Using an Automated Online SPE-LC-MS/MS Method.

Changes in thyroid hormone (TH) levels in rat brain at early developmental stages are correlated with adverse effects on offspring development. To characterize the ability of substances to interfere with the TH concentrations in, e.g., rat brain, it is essential to know the mean TH concentrations in this tissue under control conditions. In this publication, an online solid-phase extraction (SPE) liquid chromatography (LC) tandem mass spectrometry (MS/MS) method was validated and used to measure TH metabolites (T4, T3, rT3, T2 and T1) in the brains of untreated rats. Data on TH concentrations in the whole brain and separate data from the cerebellum and the cortex are shown. The corresponding samples were gathered from young rats at postnatal days (PND) 4 and 21/22 and from adult rats. The results show inter alia the high accuracy and precision of the method, and LOQs of 0.02 ng/mL were determined for T1, T2 and rT3 and of 0.15 ng/mL for T3 and T4. Technical variability is low, as shown by the relative standard deviations of 7.5-20%. For our rat model, we found that T4, T3 and T2 concentrations rise from PND4 to PND21, whereas the rT3 concentration decreases; as well as there is no statistical difference between TH concentrations in the male and female rat brain. This method is suitable to analyze TH metabolites in the brain and build up a database of historical TH concentrations in control rats. Together, this yields a robust diagnostic tool to detect potentially adverse disturbances of TH homeostasis in the most vulnerable anatomic structure.

Research Note: Non-invasive urate sphere corticosterone metabolite as a novel biomarker for heat stress in poultry

Heat stress (HS) poses a critical concern for the global poultry industry. To better understand its impact and mechanism on poultry species, as well as to develop effective HS mitigation options, it is crucial to validate reliable and effective biomarkers of HS. In this study, broiler chickens (96 mixed-sex, 1-day-old) were randomly assigned to 2 environmental conditions: HS at 31°C for 8 h/d versus a thermoneutral condition (TN) at 24°C ± 0.2 throughout the day, from d 21 to d 28. After 7 d of cyclic HS, blood serum samples and the urate sphere (the white portion of the chicken excreta) were collected to measure specific HS biomarkers, including corticosterone, heat shock protein 70 (HSP70), Triiodothyronine (T3), and urate sphere corticosterone metabolite. The results showed that the concentrations of HSP70, T3, and serum corticosterone were not significantly different (P > 0.05) between the heat-stressed and thermoneutral birds in this study. However, heat-stressed birds recorded higher (P < 0.01) concentration (pg/mL) of urate corticosterone metabolite compared to TN birds. Data presented here thus provide preliminary evidence suggesting the use of non-invasive urate sphere corticosterone metabolite as a heat stress biomarker in poultry.

Exploring Thermoregulatory Responses and Hormonal Changes in Heat Stressed Assam Hill Goats

Background: Livestock productivity and health are adversely affected by heat stress (HS). The aim of this study was to determine the effects of HS on the thermoregulation and hormonal profile in Assam Hill Goats reared in the subtropical hilly regions of Meghalaya so as to arrive at a conclusion on its heat adaptation abilities. Methods: An experiment was conducted during the year 2022 for 120 days with twelve (12) Assam Hill Goats, aged between 3-5 months, randomly divided into 2 groups (n=6 per group). The goats in group I were exposed to HS through natural exposure to sunlight during the extreme summer months (May to August) for 07 hours (8 AM to 3 PM) during grazing. The control animals (CON, group II) were maintained under shade with no exposure to sunlight. Thermoregulatory responses viz., rectal temperature, respiratory rate and pulse rate and body weight data were recorded every 15 days interval of the sampling period. The hormonal profile viz., serum T3 (nmol/L), T4 (nmol/L) and Cortisol (ng/mL) were also determined. Result: Results revealed a significant (p less than 0.05) increase in rectal temperature, pulse rate (day 45 onwards to day 120) and respiratory rate in HS group in comparison to CON. A significantly (p less than 0.05) lower average daily gain was recorded in HS group. Serum T3 and T4 concentrations were significantly (p less than 0.05) reduced and cortisol concentration was significantly (p less than 0.05) elevated in HS group in comparison to CON. In conclusion, Assam Hill Goats exposed to environmental HS shows elevated thermoregulatory responses, decreased thyroid hormone activity and increased cortisol activity to reduce production to support life sustaining activities in the hilly regions.

Slatted floor reduces the welfare and increases the foot pad dermatitis and growth performance of Turkeys under Egyptian conditions.

When Turkeys' legscome in contact with their dropping during the growing stage results in footpad dermatitis condition which affects the poult's welfare and productivity. Our experiment aimed to detect the impact of various bedding substrates on the wellbeing, and performance of growing Turkey under Egyptian conditions. 180-day-old Turkey poults were allocated into three treatments. In treatment I, the poults [60 each with three replicates (n = 20 birds)] were kept on wood shavings (WS); in the second treatment, the poults were housed on chopped wheat straw (CWS). However, in the third treatment, they kept on a plastic slatted floor (PSF). The greater feed intake and body weight were recorded in poults reared in PSF compared with those kept in other treatments (WS and CWS). Feed conversion ratio did not show any significant difference. The mortality percentage was higher in the PSF group than in the WS one. The frequency of feeding and drinking behavior was higher in poults reared on WS treatment compared with other treatments CWS and PSF. On the other hand, resting behavior showed the highest frequency in poults kept in PSF. Contrary, the lowest frequency of walking behavior was recorded in poults reared in PSF treatment. In addition, the poults kept in WS had a longer tonic immobility reaction period followed by those kept in PSF and CWS. Concerning foot-pad dermatitis, the highest score of 0 was observed in the CWS group, while the highest score of 1 was recorded among poults kept in the WS group. On the other side, the highest score 2, 3, and 4 was observed in the poults reared in the PSF group. Heterophil/Lymphocyte ratio of Turkey poults was higher in PSF. While T3 and T4 concentrations in blood were not affected by using different bedding materials. It is concluded that the slatted floor was good for Turkey producers from the point of performance but, it is the worst from the point of welfare.

Association between maternal hypothyroidism, baby birth weight, and adult cardiovascular disease risk: insights from ECG measurements.

Thyroid hormone (TH) deficiency during pregnancy may affect cardiovascular function in offspring rats. This study aimed to evaluate the effect of TH deficiency during gestation, on the electrocardiogram indices of young and middle-aged offspring of male rats. Eight female rats were equally divided into hypothyroid and control groups. The hypothyroid mothers received 0.025% 6-propyl-2-thiouracil (PTU) in drinking water throughout pregnancy, while control mothers consumed only tap water. Following birth, male rats from each group were observed for 4 months (young age) and 12 months (middle-aged). The group known as fetal hypothyroid (FH) consisted of rats born from hypothyroid mothers. The serum T4 and TSH concentrations from mothers and newborn male rats were assayed at the end of gestation. Lead II electrocardiogram (ECG) was recorded for 5 minutes using Power Lab, AD Instruments. There was a significant rise in the P wave voltage in young FH rats, whereas, it was decreased in middle-aged control and FH rats. The voltage of QRS decreased and its duration increased in the young and middle-aged FH rats compared to the corresponding control groups. Duration and voltage of the T wave were significantly altered in the young and middle-aged FH groups. PR and QT intervals significantly increased in the young and middle-aged FH groups compared to their controls. Maternal hypothyroidism affected the electrocardiogram indices of offspring rats, possibly signaling cardiovascular problems later in life.

Nanopore surface engineering of molecular imprinted mesoporous organosilica for rapid and selective detection of L-thyroxine

To develop a biosensing platform for precise diagnosis and management of thyroid-related diseases, the sensitive and selective recognition and identification of L-thyroxine (T4), a thyroid hormone, remains challenging. We herein introduce T4-imprinted mesoporous organosilica (T4-IMO) for sensitive and specific detection of T4 via the sophisticated engineering of pore surfaces using additives with different polarities. The pore surface of T4-IMO emitting a stable fluorescence signal is simply modified by fixed additives. Additives embedded in the pore surface promote the rebinding response of T4 into the recognized cavities, subsequently sensitizing T4 detection. Notably, T4-IMO containing abundant fluorine elements on the pore surface shows a high affinity toward T4, remarkably boosting the rebinding capacity. In addition to good selectivity to T4, the “turn-off” fluorescent signal exhibits a linear relationship with the logarithm of T4 concentration in a range of 0–500nM with a detection limit of 0.47nM in synthetic urine samples. Our findings can establish an insightful strategy for the rational design of molecular-recognition-based sensor systems for the selective and sensitive detection of target analytes.

Relationship between thyroid function and sex hormones in female German shepherd dogs.

Several variables influence the serum concentration of thyroid hormones in dogs, including breed, age, drugs, and concurrent diseases. However, data regarding the interaction between thyroid function and the estrous stage of female dogs are limited. Estrous stage may influence thyroid function in German Shepherd dogs. Longitudinal, observational, non-randomized cohort study. The dogs were monitored during the complete estrous cycle, and different stages were determined by vaginal cytology. Two blood samples were collected at the beginning and end of each stage to analyze the following: total thyroxine (TT4), free thyroxine (fT4), total triiodothyronine (TT3), free triiodothyronine (fT3), canine thyrotropin (cTSH), progesterone, 17-β-estradiol, triglycerides, and cholesterol concentrations. Hematological and biochemical evaluations were performed at the beginning and end of the study period. Seventeen German Shepherds were included, of which 7 were bred during the study period. One dog was excluded for estrus interruption and another for suspected hypothyroidism. Serum concentrations of T4, fT4, and fT3 were negatively correlated with age. Total thyroxine demonstrated significant changes in serum concentrations between estrous stages, with higher concentrations in estrus and diestrus. Total thyroxine concentrations were positively correlated with progesterone concentrations and negatively correlated with 17-β-estradiol concentrations. Free thyroxine did not show significant variations but was positively correlated with progesterone concentrations. Canine TSH concentrations were positively correlated with 17-β-estradiol concentrations. No significant differences in thyroid hormones and cTSH concentrations were observed between diestrus during pregnancy and pseudopregnancy. Different stages of estrus can influence the measurement of TT4 in female dogs.

The correlation between iron deficiency anemia and hypothyroidism during pregnancy

Abstract Background: Pregnant women are often iron deficient, and this has adverse effects on thyroid metabolism. Impaired maternal thyroid function in pregnancy may cause neurodevelopmental delay in the offspring. Objectives: To investigate if maternal iron status is a determinant of thyroid stimulating hormone (TSH) and/or free T4 (FT4) concentrations during pregnancy. Materials and Methods: A case–control study was conducted in the Department of Obstetrics and Gynecology at Azadi Teaching Hospital, Kirkuk, Iraq over a period of 7 months from February 1st to September 1st, 2020. It included 80 pregnant women with singleton pregnancy in the obstetric outpatient clinic and labor room. Verbal consent was obtained. They were divided into: (1) case group: it included 40 cases of iron deficiency (ID) anemic pregnant women with hemoglobin level of 105 g/L and less in the second and third trimesters. (2) Control group: It included 40 cases of healthy pregnant women. Estimation of gestational age was done depending on the date of last menstrual cycle, and/or early ultrasound scan. Results: In this study, 80 pregnant women in their second and third trimesters participated. Fifty percent were anemic, had elevated serum soluble transferrin receptor and negative body iron stores, 35% had a free T4 less than 7.5 pmol/L, and 47.5% had a TSH more than 4.0 mIU/L. 47.5% who were hypothyroid had negative body iron store. Serum ferritin, soluble transferrin receptor, and body iron stores were highly significant predictors of thyroid status. Conclusions: Poor maternal iron status predicts both higher TSH and lower free T4 concentrations during pregnancy. On the basis of results, we had there may be a correlation between ID anemia of pregnant women and their thyroid status.

Supplementation of chickpea flour and spinach leaves powder in Nutri bars to overcome iron deficiency in young females

ABSTRACT This study evaluated the iron-rich Nutri bar’s effect on iron-deficient females. Iron-rich Nutri-bars made with spinach powder and chickpea flour. The physicochemical profile of the bars was measured. Socioeconomic status and anthropometric data were taken for the effectiveness of the research. This effectiveness trial included 20 girls ages 20 to 25. After that, biochemical tests, including hemoglobin, ferritin, and total iron-binding capacity (TIBC) were conducted. Results showed that the iron-rich Nutri-bars (T3, 6.60) had more moisture than other treatments. T3 protein and fiber composition was 16.90% and 4.30%. In T3, crude fat and ash content were the lowest. All the proximate analyses of incorporated spinach powder and chickpea flour indicated a significant correlation (P > .005). A jury gave treatment T3 the highest score in overall acceptability. Iron and zinc concentrations were 13.2 and 5.9 mg/100 g in T3. Post-assessment height, weight, and body mass index (BMI) indicated a very significant (P > .005) connection compared to pre-assessment (P > .005). Selected young females' hemoglobin, serum ferritin, and total iron-binding capacity were tested biochemically. After the intervention, the experimental group’s mean hemoglobin (HB) was 12.21 ± 1.14 g/dl (P > .005). Increasing patterns support the current study’s iron improvement. Serum ferritin exhibited similarly substantial outcomes. TIBC dropped when iron status increased. Conclusively, iron-rich nutri-bars supplemented with spinach leaf powder and chickpea flour increased iron status in young females.