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SummaryIn the absence of strong reproductive barriers, genetic exchanges between closely related groups of organisms with different adaptations have well-documented beneficial and detrimental consequences. In plants, pollen-mediated exchanges affect the sorting of alleles across physical landscapes, and influence rates of hybridisation. How these dynamics affect the emergence and spread of novel ecological strategies remains only partially understood.We use phylogenomics and population genomics to retrace the origin of two geographically overlapping ecotypes of the African grass Alloteropsis angusta.We report the existence of a previously undescribed ecotype inhabiting miombo woodlands and grasslands. The two ecotypes have divergent nuclear genomes. However, the seed-transported chloroplast genomes are consistently shared by distinct ecotypes inhabiting the same region. These patterns suggest that the nuclear genome of one ecotype can reach the seeds of the other via pollen movements, with strong selection subsequently sorting nuclear alleles by habitat.The contrasting ecotypes of A. angusta can use each other as a gateway to new locations across a large part of Africa. Coupled with newly discovered hybridisation with the sister species A. semialata, our results show that hybridisation can facilitate the geographical dispersal of distinct ecotypes of the same grass species.

Background: Antithyroid drugs (ATDs) are first-line treatment for Graves’ hyperthyroidism worldwide, but relapses are frequent. The reliability of individual risk factors to predict at baseline subsequent relapse is poor. Predictive scores grouping single risk factors might help to select the best treatment (pharmacological vs. ablative). Objective: To assess the predictivity of a recently developed score (Clinical Severity Score, CSS) and to compare it with another score (GREAT score). Patients: A retrospective observational, single-center study was conducted of 387 consecutive, newly diagnosed Graves’ patients, who completed an 18–24 months ATD course and were followed for at least 2 years. Results: Hyperthyroidism relapsed in 185 patients (48%). At diagnosis and before treatment, the relapse group had higher serum TSH-receptor antibody and free thyroxine levels and larger goiters than the remission group, with no differences in Graves’ orbitopathy prevalence and severity. In the multivariate analyses, only large goiter size was significantly associated with an increased recurrence hazard ratio. Using CSS, the risk of relapse increased from 36% in the mild category and 49% in the moderate category to 59% in the severe category, with quite a good area under the curve (AUC) (0.60; 95% CI: 0.55; 0.66). GREAT score showed an increase in relapse from 34% for class I (mild) and 49% for class II (moderate) to 64% for class III (severe) (AUC, 0.63; CI: 0.58; 0.68). Conclusions: Both CSS and GREAT score are useful, although imperfect, tools to predict at baseline relapse of hyperthyroidism after treatment. In real life they may help the clinician to tailor a treatment for newly diagnosed Graves’ hyperthyroidism.

IgG4-related hypophysitis (IgG4-RH) is a rare disease, which can occur singularly or as manifestation of a systemic IgG4-related disease (IgG4-RD). Less than one hundred cases have been reported in the literature, very few of which were histopathologically documented. We analyzed the clinical, radiological, and histopathological features of two cases of IgG4-RH, the former observed in a 66-year-old man in the context of an IgG4-RD, and the latter affecting a 21-year-old woman, as an isolated lesion. In addition, we performed a comprehensive review of the previously published histopathologically documented cases of IgG4-RH. Pituitary samples from both patients showed dense lymphoplasmacytic infiltration, interstitial and storiform fibrosis, and high numbers of IgG4-positive plasma cells, consistent with IgG4-RH. From the literature review, we retrieved 18 papers reporting a total of 22 cases of histopathologically documented IgG4-RH. The revision of these cases, also including the two reported herein, showed an equal distribution of IgG4-RH in the two sexes, albeit significant clinico-pathological variation was found between cases arisen in female and male patients, respectively. In detail, IgG4-RH females were affected in their second-third decade of life, with a solitary pituitary lesion, low IgG4 serum level, and frequent association with autoimmune disorders. By contrast, IgG4-RH in men was a disease of the elderly, often in the context of a systemic IgG4-RD, with high IgG4 serum levels. Our study shows that IgG4-RH, as currently defined, is a clinically heterogenous disease, with different features in the two sexes. Indeed, cases diagnosed in young women, as our case 2, mostly do not present other evidence of IgG4-RD and might be better classified as lymphocytic hypophysitis with abundant IgG4+ plasma cells. For this reason, the histopathological examination of the pituitary lesion, particularly in female patients, may still be useful for a correct differential diagnosis with other variants of primary hypophysitis.

Hypothyroidism is complicated by neuromuscular symptoms (myalgias, slowness of movements, and tiredness) and signs (easy fatigability and cramps), which may have a negative impact on general well-being and quality of life. In a pilot, prospective, controlled study, we investigated the features of muscle dysfunction in hypothyroidism by disease questionnaire, biochemical measures, and physical performance tests.Fifty-seven consecutive patients with newly diagnosed hypothyroidism were enrolled, 27 subclinical (S-Hypo) and 30 overt (O-Hypo). A series of 30 euthyroid subjects, with similar demographic characteristics, served as controls. Patients were administered a short disease questionnaire and underwent laboratory exams and standardized physical tests, both at baseline and after restoration of biochemical euthyroidism.Compared to euthyroid controls, the O-Hypo group showed significantly higher prevalence of neuromuscular symptoms and significantly higher serum creatine phosphokinase (CPK) levels (p value 0.0001). S-Hypo had slightly higher CPK levels and prevalence of neuromuscular symptoms than controls. Both S-Hypo and O-Hypo patients performed worse than controls in the six-minute walking test. Differences between patients and controls in handgrip strength test and timed chair standing test failed to reach statistical significance (although a trend was noticeable), possibly due to the small sample size. In O-Hypo, an inverse correlation was found between CPK levels and the handgrip strength test (p value 0.001). Restoration of euthyroidism was associated with normalization of questionnaire responses, six-minute walking test, as well as serum CPK levels.In addition to neuromuscular symptoms, hypothyroidism is associated with abnormalities of physical performance. The six-minute walking test is the most valuable test to assess this aspect. In the pilot study, levothyroxine therapy could reverse muscle functional abnormalities.

The Merseburg triad (hyperthyroidism, goiter, and orbitopathy) characterizes classical description of Graves’ disease (GD). Aim of this observational, longitudinal study was to evaluate the current clinical features of newly diagnosed GD in Italy. In two Northern Italy centers (Varese and Pavia), 283 consecutive patients (211 women, 72 men; mean age 47.4 years) with newly diagnosed GD were recruited in the years 2010–2014. Diagnosis was based on established criteria, and thyroid volume was assessed by ultrasonography. A clinical severity score (CSS) to assess the overall disease severity was developed by grading each component of the Merseburg triad. At diagnosis, 45 % of patients had no goiter, and 30 % had a small goiter. The proportion of goitrous patients was much lower than in two Italian studies performed 20–30 years ago. Hyperthyroidism was subclinical in 16 % and mild in 29 % of patients, and Graves’ orbitopathy was present in 20 %, usually mild, and active in only 2.5 % of patients. Using the CSS, less than half (44 %) of the patients had severe GD, while 22 % had mild and 34 % moderate disease. CSS was associated with a significantly higher risk of poorly controlled hyperthyroidism at 6 months. In Italy, a relevant proportion of Graves’ patients at diagnosis have mild to moderate GD; about half of them have no goiter, slightly less than one-fifth have subclinical hyperthyroidism, and only 20 % have GO. Thus, the clinical phenotype of GD is milder than in the past, possibly due to both earlier diagnosis and treatment, and improved iodine nutrition.

Stylosanthes capitata Vogel is an important forage legume in tropical and subtropical regions. To study the response of S. capitata to the moderate warming expected as a result of climate change, plants were subjected to elevated temperature (2 °C increase over the ambient temperature) in a temperature free-air controlled enhancement (T-FACE) facility. Photosystem II (PSII) performance, the activity of antioxidant enzymes, the chlorophyll index, the leaf area index (LAI) and the aboveground biomass production were evaluated. The maximum PSII quantum yield (FV/FM) and the quantum yield of regulated energy dissipation Y (NPQ) were not affected by the warming. However, we observed a significant increase in the electron transport rate (ETR), the non-photochemical energy dissipation (NPQ), the effective PSII quantum yield Y(II) and the coefficient of photochemical quenching (qP) in the warmed leaves compared with the control leaves. In contrast, a significant reduction in the quantum yield of the relative reduction state of QA (1-qP) and non-regulated power dissipation Y(NO) was observed in the warmed leaves. The increase in ETR under moderate warming was associated with the increase (31%) in chlorophyll content. The activities of antioxidant enzymes increased in the leaves of the warmed plants, but the malondialdehyde (MDA) content of the leaves was not affected by warming, suggesting that higher levels of the antioxidant defense system induced by warming may improve the protection of photosynthesis against oxidative damage and attenuate the destructive effects of reactive oxygen species. As a result of warming, leaf area index (LAI) and biomass production increased by 32% and 16%, respectively. The improved PSII functioning of the warmed leaves of S. capitata may reflect their capacity to acclimate better to warming growth conditions. We conclude that the warming induced by increasing the temperature by 2 °C, under non stressing conditions, was beneficial for the physiology and for the biophysical and physiological processes involved in plant growth of S. capitata, suggesting that slight increases in the leaf temperature may benefit some plants, especially those in tropical environments.