Short range hunters: Exploring the function and constraints of water shooting in dwarf gouramis

Ballistic predation is a rare foraging adaptation: in fishes, most attention has focused on a single genus, the archerfish, known to manipulate water to shoot down prey above the water surface. However, several gourami species also exhibit apparently similar ‘shooting’ behaviour, spitting water up to 5cm above the surface. In a series of experiments, we explored the shooting behaviour and aspects of its significance as a foraging ability in the dwarf gourami (Trichogaster lalius). We investigated sex differences in shooting abilities as gourami shooting may be related to the sex-specific bubble nest manufacture - where males mix air and water at the surface to form bubbles - finding that actually both sexes are equally able to shoot and learn to shoot a novel target. In a second experiment, we presented untrained gouramis with opportunities to shoot at live prey and found they successfully shot down both fruit flies and crickets. Finally, we explored the effect of target height on shooting performance to establish potential constraints of shooting as a foraging ability. The frequency of attempted shots and success of hitting targets decreased with height while latency to shoot increased. We also observed that repeatable individual differences account for variation in these measures of shooting performance. Together our results provide evidence that gourami shooting has a foraging function analogous to that of archerfish. Gourami shooting may serve as an example of convergent evolution and provide opportunities for comparative studies into the, yet unexplored, ecology and evolution of shooting in fishes.

Impact of delayed diagnosis on catch-up growth of children and adolescents with primary hypothyroidism due to Hashimoto’s thyroiditis

Objectives: There is a paucity of data on impact of therapy of Hashimoto’s thyroiditis (HT) on catch-up growth. The objective of the study was to determine whether delayed diagnosis of HT and overt primary hypothyroidism has an impact on the catch-up of children and adolescents. Material and Methods: We conducted a prospective observational study over 3 years, in the thyroid clinic of a referral unit in South India. We assessed chronological age (CA), auxological parameters, clinical presentation, bone age (BA), and predicted adult height (PAH) in subjects with Hashimoto’s thyroiditis and overt primary hypothyroidism. Management and follow-up done as per standard protocols and study parameters reassessed after 1 year of therapy. Results: We recruited 38 subjects and divided them into two groups – Group 1 with BA within 2 standard deviations (SD) of CA (n = 20) and Group 2 beyond 2 SD (n = 18). During 1 year follow-up, height Z-scores were −0.1 ± 1.4 (baseline) and −0.1 ± 1.1 (endpoint) and −1.7 ± 1.7 (baseline) and −1.3 ± 1.3 (endpoint) in Groups 1 and 2, respectively. BA: CA ratio changed from 1.0 ± 0.1 to 1.0 ± 0.1 in Group 1 (P > 0.05) versus 0.7 ± 0.2 to 0.9 ± 0.1 in Group 2 (P < 0.05). The number of children who were pre-pubertal: pubertal changed from 15:5 to 11:9 in Group 1 and 14:4 to 7:11 in Group 2. For Group 1, baseline PAH Z score was −0.5 ± 1.7 and endpoint PAH Z score was −0.7 ± 1.6 versus a target height Z score of −1.1 ± 1.1 (P > 0.05); Group 2, the baseline PAH Z score −1.1 ± 1.6 and endpoint PAH Z score −2.2 ± 1.4 versus target height Z-score of −0.4 ± 1.7. Conclusion: Delayed diagnosis and treatment of juvenile autoimmune hypothyroidism results in permanent loss of height potential.

Adult Height in 299 Patients with Turner Syndrome with or without Growth Hormone Therapy: Results and Literature Review

<b><i>Context:</i></b> Treatment with growth hormone (GH) is considered effective in improving adult height (AH) in Turner syndrome (TS). However, there are few studies comparing AH between treated patients and a concurrent untreated group. <b><i>Objective:</i></b> To assess the efficacy of GH treatment in improving AH in TS and to review previous published studies with treated and untreated groups. <b><i>Participants and Methods:</i></b> We retrospectively analyzed clinical data and AH of a large cohort of GH-treated (<i>n</i> = 168) and untreated (<i>n</i> = 131) patients with TS. Data are shown as median and interquartile range (IQR). We assessed pretreatment variables related with AH and compared our results with 16 studies that also included an untreated group. <b><i>Results:</i></b> The GH-treated group was 6.2 cm taller than the untreated group (AH = 149 cm [IQR 144.5–152.5 cm] vs. 142.8 cm [IQR 139–148 cm], <i>p</i> &#x3c; 0.001) after 4.9 years of GH treatment with a dose of 0.35 mg/kg/week. AH SDS corrected for target height (TH) was 7.2 cm higher in GH-treated patients. AH SDS ≥−2 was more frequent in GH-treated patients (43%) than in untreated patients (16%, <i>p</i> &#x3c; 0.001). AH SDS was also more frequently within the TH range in the GH-treated group (52%) than in the untreated group (15%, <i>p</i> &#x3c; 0.001). Height SDS at start of GH therapy and TH SDS were positively correlated with AH (<i>p</i> &#x3c; 0.001; <i>R</i>² = 0.375). Considering the current result together with previous similar publications, a mean AH gain of 5.7 cm was observed in GH-treated (<i>n</i> = 696) versus untreated (<i>n</i> = 633) patients. <b><i>Conclusions:</i></b> Our study strengthens the evidence for efficacy of GH therapy in patients with TS from different populations.

Final Height in Pubertal Short Stature Boys Treated with GH Combination with Letrozole: A retrospective study

BackgroundThe growth potential of pubertal short stature boys is limited by the effect of estrogen on epiphyseal fusion. This study aims to identify the efficacy and safety of growth hormone (GH) combination with letrozole on final adult height (FAH) in pubertal short stature boys. MethodsThis is a retrospective study. Among pubertal short stature boys who treated with GH and letrozole were be followed up in our hospital, 20 cases reached FAH. ResultsBaseline chronological age were 12.12±1.14yr, bone age were 13.00±0.93yr. The treatment duration was 1.94±0.67yr. The height standard deviation score for bone age was increased from -1.46±0.51 to -0.12±0.57 (p<0.000). The predicted FAH before treatment, predicted FAH after treatment, FAH, and genetic target height were 161.02 ±4.12 cm, 172.11±4.20 cm, 172.67±2.72cm and 167.67±3.56 cm, respectively. There was significant differences between predicted FAH before treatment and after treatment (p<0.000), as well as predicted FAH before treatment and genetic target height (p<0.000).The predicted FAH after treatment was higher than that of genetic target height (p<0.001), as well as FAH and genetic target height (p<0.000). ConclusionsThe GH combination with letrozole can enhance the FAH in pubertal short stature boys. No significant side effects were observed.

Hydrocortisone Suspension Provides Similar Growth Outcomes as Hydrocortisone Tablets in Young Children With Congenital Adrenal Hyperplasia: A Cross Sectional Study

Young children with CAH require small doses (0.1–1.25mg) and incremental adjustments of hydrocortisone (HC) to control excess androgen production and avoid the negative effects of overtreatment. A recent 6 hour pharmacokinetic/pharmacodynamic study reported that alcohol-free HC suspension provides similar cortisol exposure to tablets (1), but more data is needed to assess its clinical efficacy. We performed a chart review to determine the effect of the alcohol-free HC suspension compared to tablets on height, weight, BMI, bone age z-scores and corrected height z-scores to target height z-scores in children aged 2 yrs and 4 yrs in a cohort with classic CAH. Independent 2-sample t-tests examined cumulative and average HC dose at 2 and 4 yrs. Triple logistic modeling of longitudinal heights were used to calculate predicted near-adult height. Adjusted linear regression models assessed the effect of HC suspension compared to tablets on final adult height. Charts of 130 children (70 females, 100 salt wasting and 30 simple virilizing) were reviewed. At 2 yrs, 97 were treated with tablets and 33 with suspension (17 previously switched from tablets). At 4 yrs, 89 were treated with tablets and 41 with suspension (25 switched). No significant differences in height or BMI z-scores at both 2 and 4 yrs, before or after adjusting for age at diagnosis and sex were found. Bone age z-scores averaged 7.2 SDs lower for patients treated with HC suspension only compared to patients on HC tablets at age 4 (p&lt;0.001), and 5.93 SDs lower for patients switched from tablets to suspension compared to tablets (p&lt;0.001). The suspension group received 16% lower (p=0.055) and 25% lower (p=0.002) cumulative HC doses by the ages of 2 yrs and 4 yrs respectively. Average daily HC dose was lower by 3.44 and by 4.46 mg/m2/d over the first 2 and 4 yrs of life respectively. No significant differences were found between patients treated with tablets and suspension in the predicted final adult height, its z-score or its corrected z-score to target height after adjusting for age at diagnosis, sex and diagnosis. Our data indicates that treatment with alcohol-free HC suspension decreased androgen exposure as shown by lower bone age z-scores, generated no significant differences in SDS in observed height, BMI or predicted near-adult height, and allowed for lower average and cumulative daily HC dose compared to HC tablets in children with CAH. Reference: (1) Sarafoglou et al., J Clin Pharmacol.2015;55(4):452–7.

A new global grid-based weighted mean temperature model considering vertical nonlinear variation

Global navigation satellite systems (GNSS) have been proved to be an excellent technology for retrieving precipitable water vapor (PWV). In GNSS meteorology, PWV at a station is obtained from a conversion of the zenith wet delay (ZWD) of GNSS signals received at the station using a conversion factor which is a function of weighted mean temperature (Tm) along the vertical direction in the atmosphere over the site. Thus, the accuracy of Tm directly affects the quality of the GNSS-derived PWV. Currently, the Tm value at a target height level is commonly modeled using the Tm value at a specific height and a simple linear decay function, whilst the vertical nonlinear variation in Tm is neglected. This may result in large errors in the Tm result for the target height level, as the variation trend in the vertical direction of Tm may not be linear. In this research, a new global grid-based Tm empirical model with a horizontal resolution of 1∘ × 1∘ , named GGNTm, was constructed using ECMWF ERA5 monthly mean reanalysis data over the 10-year period from 2008 to 2017. A three-order polynomial function was utilized to fit the vertical nonlinear variation in Tm at the grid points, and the temporal variation in each of the four coefficients in the Tm fitting function was also modeled with the variables of the mean, annual, and semi-annual amplitudes of the 10-year time series coefficients. The performance of the new model was evaluated using its predicted Tm values in 2018 to compare with the following two references in the same year: (1) Tm from ERA5 hourly reanalysis with the horizontal resolution of 5∘ × 5∘; (2) Tm from atmospheric profiles from 428 globally distributed radiosonde stations. Compared to the first reference, the mean RMSEs of the model-predicted Tm values over all global grid points at the 950 and 500 hPa pressure levels were 3.35 and 3.94 K, respectively. Compared to the second reference, the mean bias and mean RMSE of the model-predicted Tm values over the 428 radiosonde stations at the surface level were 0.34 and 3.89 K, respectively; the mean bias and mean RMSE of the model's Tm values over all pressure levels in the height range from the surface to 10 km altitude were −0.16 and 4.20 K, respectively. The new model results were also compared with that of the GTrop and GWMT_D models in which different height correction methods were also applied. Results indicated that significant improvements made by the new model were at high-altitude pressure levels; in all five height ranges, GGNTm results were generally unbiased, and their accuracy varied little with height. The improvement in PWV brought by GGNTm was also evaluated. These results suggest that considering the vertical nonlinear variation in Tm and the temporal variation in the coefficients of the Tm model can significantly improve the accuracy of model-predicted Tm for a GNSS receiver that is located anywhere below the tropopause (assumed to be 10 km), which has significance for applications requiring real-time or near real-time PWV converted from GNSS signals.

Archerfish coordinate fin-maneuvers with their shots

Archerfish down a variety of aerial prey from a range of distances using water jets that they adjust to size and distance of their prey. We describe here that characteristic rapid fin maneuvers, most notably of the pectoral and pelvic fins, are precisely coordinated with the release of the jet. We discovered these maneuvers in two fish that had been trained to shoot from fixed positions at targets in different height, whose jets had been characterized in detail and who remained stable during their shots. Based on the findings in these individuals we examined shooting-associated fin-movement in 28 further archerfish of two species that could shoot from freely chosen positions at targets of different height. Slightly before onset of the water jet, at a time when the shooter remains stable, the pectoral fins of all shooters switched from asynchronous low-amplitude beating to a synchronized rapid forward flap. Onset and duration of the forward and subsequent backward flap were robust across all individuals and shooting angles but depended on target height. The pelvic fins are slowly adducted at the start of the jet and stop after its release. All other fins also showed a characteristic sequence of activation, some starting about 0.5 s before the shot. Our findings suggest that shooting-related fin-maneuvers are needed to stabilize the shooter and that they are an important component in the precise and powerful far-distance shooting in archerfish.

Definition and prevalence of familial short stature

Objective To verify the prevalence of novel definitions of familial short stature on a cross-sectional cohort of children referred for short stature when their height and that of both parents were measured. Methods We consecutively enrolled 65 individuals referred for short stature when both parents were present. We defined “target height-related short stature” (TH-SS) when child’s height is ≤ − 2 SDS and included in the range of target height; suspected “autosomal dominant short stature” (AD-SS) when child height and at least one parent height are ≤ − 2 SDS; “constitutional familial short stature” (C-FSS) when a child with TH-SS does not have any parents with height ≤ − 2 SDS. Results Of 65 children referred for SS, 48 individuals had a height ≤ − 2 SDS. Based on the parents’ measured heights, 24 children had TH-SS, 16 subjects AD-SS, and 12 individuals C-FSS. If we had considered only the parents’ reported height, 3 of 24 children with TH-SS, 9 of 16 with AD-SS, and 10 of 12 with C-FSS would have been lost. Conclusion We suggest novel definitions to adequately detect and approach the cases of FSS since C-FSS (25%) might not need any specific investigation, while on the contrary, AD-SS (33%) should undergo genetic evaluation. Moreover, this study underlines that adequate measurement and consideration of children’s and parents’ heights (individually and together) are crucial in the clinical evaluation of every child with short stature.