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Structure-(in)dependent Interpretation of Phrases in Humans and LSTMs
In this study, we compared the performance of a long short-term memory (LSTM) neural network to the behavior of human participants on a language task that requires hierarchically structured knowledge. We show that humans interpret ambiguous noun phrases, such as second blue ball, in line with their hierarchical constituent structure. LSTMs, instead, only do so after unambiguous training, and they do not systematically generalize to novel items. Overall, the results of our simulations indicate that a model can behave hierarchically without relying on hierarchical constituent structure
The position of combined medical treatment in acromegaly
Advances in combination medical treatment have offer new perspectives for acromegaly patients with persistent disease activity despite receiving the available medical monotherapies. The outcomes of combination medical treatment may reflect both additive and synergistic effects. This review focuses on combination medical treatment and its current position in acromegaly, based on clinical studies evaluating the efficacy and safety of combined medical treatment(s) and our own experiences with combination therapy. Arch Endocrinol Metab. 2019;63(6):646-52
Chromogranin A as serum marker for neuroendocrine neoplasia: comparison with neuron-specific enolase and the alpha-subunit of glycoprotein hormones
Chromogranin A (CgA) is gaining acceptance as a serum marker of
neuroendocrine tumors. Its specificity in differentiating between
neuroendocrine and nonneuroendocrine tumors, its sensitivity to detect
small tumors, and its clinical value, compared with other neuroendocrine
markers, have not clearly been defined, however. The objectives of this
study were to evaluate the clinical usefulness of CgA as neuroendocrine
serum marker. Serum levels of CgA, neuron-specific enolase (NSE), and the
alpha-subunit of glycoprotein hormones (alpha-SU) were determined in 211
patients with neuroendocrine tumors and 180 control subjects with
nonendocrine tumors. The concentrations of CgA, NSE, and alpha-SU were
elevated in 50%, 43%, and 24% of patients with neuroendocrine tumors,
respectively. Serum CgA was most frequently increased in subjects with
gastrinomas (100%), pheochromocytomas (89%), carcinoid tumors (80%),
nonfunctioning tumors of the endocrine pancreas (69%), and medullary
thyroid carcinomas (50%). The highest levels were observed in subjects
with carcinoid tumors. NSE was most frequently elevated in patients with
small cell lung carcinoma (74%), and alpha-SU was most frequently elevated
in patients with carcinoid tumors (39%). Most subjects with elevated
alpha-SU levels also had elevated CgA concentrations. A significant
positive relationship was demonstrated between the tumor load and serum
CgA levels (P < 0.01, by chi 2 test). Elevated concentrations of CgA, NSE,
and alpha-SU were present in, respectively, 7%, 35%, and 15% of control
subjects. Markedly elevated serum levels of CgA, exceeding 300
micrograms/L, were observed in only 2% of control patients (n = 3)
compared to 40% of patients with neuroendocrine tumors (n = 76). We
conclude that CgA is the best general neuroendocrine serum marker
available. It has the highest specificity for the detection of
neuroendocrine tumors compared to the other neuroendocrine markers, NSE
and alpha-SU. Elevated levels are strongly correlated with tumor volume;
therefore, small tumors may go undetected. Although its specificity cannot
compete with that of the specific hormonal secretion products of most
neuroendocrine tumors, it can have useful clinical applications in
subjects with neuroendocrine tumors for whom either no marker is available
or the marker is inconvenient for routine clinical use
Multivariable Prediction Model for Biochemical Response to First-Generation Somatostatin Receptor Ligands in Acromegaly
CONTEXT: First-generation somatostatin receptor ligands (fg-SRLs) represent the mainstay of medical therapy for acromegaly, but they provide biochemical control of disease in only a subset of patients. Various pretreatment biomarkers might affect biochemical response to fg-SRLs. OBJECTIVE: To identify clinical predictors of the biochemical response to fg-SRLs monotherapy defined as biochemical response (insulin-like growth factor (IGF)-1 ≤ 1.3 × ULN (upper limit of normal)), partial response (>20% relative IGF-1 reduction without normalization), and nonresponse (≤20% relative IGF-1 reduction), and IGF-1 reduction. DESIGN: Retrospective multicenter study. SETTING: Eight participating European centers. METHODS: We performed a meta-analysis of participant data from 2 cohorts (Rotterdam and Liège acromegaly survey, 622 out of 3520 patients). Multivariable regression models were used to identify predictors of biochemical response to fg-SRL monotherapy. RESULTS: Lower IGF-1 concentration at baseline (odds ratio (OR) = 0.82, 95% confidence interval (CI) 0.72-0.95 IGF-1 ULN, P = .0073) and lower bodyweight (OR = 0.99, 95% CI 0.98-0.99 kg, P = .038) were associated with biochemical response. Higher IGF-1 concentration at baseline (OR = 1.40, (1.19-1.65) IGF-1 ULN, P ≤ .0001), the presence of type 2 diabetes (oral medication OR = 2.48, (1.43-4.29), P = .0013; insulin therapy OR = 2.65, (1.02-6.70), P = .045), and higher bodyweight (OR = 1.02, (1.01-1.04) kg, P = .0023) were associated with achieving partial response. Younger patients at diagnosis are more likely to achieve nonresponse (OR = 0.96, (0.94-0.99) year, P = .0070). Baseline IGF-1 and growth hormo
Excellent response to pasireotide therapy in an aggressive and dopamine-resistant prolactinoma.
peer reviewedProlactinomas are the most commonly encountered pituitary adenomas in the clinical setting. While most can be controlled by dopamine agonists, a subset of prolactinomas are dopamine-resistant and very aggressive. In such tumors, the treatment of choice is neurosurgery and radiotherapy, with or without temozolomide. Here, we report a patient with an highly aggressive, dopamine-resistant prolactinoma, who only achieved biochemical and tumor control during pasireotide long-acting release (PAS-LAR) therapy , a second-generation somatostatin receptor ligand (SRL). Interestingly, cystic degeneration, tumor cell necrosis, or both was observed after PAS-LAR administration suggesting an antitumor effect. This case shows that PAS-LAR therapy holds clinical potential in selective aggressive, dopamine-resistant prolactinomas that express somatostatin (SST) receptor subtype 5 and appears to be a potential new treatment option before starting temozolomide. In addition, PAS-LAR therapy may induce cystic degeneration, tumor cell necrosis, or both in prolactinomas
Endocrine disorders are prominent clinical features in patients with primary antibody deficiencies
Background: Primary antibody deficiencies (PADs) and anterior pituitary dysfunction are both rare conditions. However, recent studies have remarkably reported the occurrence of anterior pituitary dysfunction in PAD patients. Methods: In this cross-sectional, single-center study we evaluated the prevalence of endocrine disorders in adult PAD patients. Our study focused on common variable immunodeficiency (CVID), immunoglobulin G (IgG) subclass deficiency (IgGSD), and specific anti-polysaccharide antibody deficiency (SPAD). We assessed hormone levels, performed provocative tests and genetic testing in a subset of patients by direct sequencing of the nuclear factor kappa beta subunit 2 (NFKB2) gene and primary immunodeficiency (PID) gene panel testing by whole exome sequencing (WES). Results: Our results demonstrated that one out of 24 IgGSD/SPAD patients had secondary hypothyroidism and three out of 9 men with IgGSD/SPAD had secondary hypogonadism. Premature ovarian failure was observed in four out of 9 women with CVID and primary testicular failure in one out of 15 men with CVID. In two out of 26 CVID patients we found partial adrenal insufficiency (AI) and in one out of 18 patients with IgGSD/SPAD secondary AI was found. Moreover, in one out of 23 patients with CVID and in two out of 17 patients with IgGSD/SPAD severe growth hormone deficiency (GHD) was found, while one patient with IgGSD/SPAD showed mild GHD. Combined endocrine disorders were detected in two women with CVID (either partial secondary AI or autoimmune thyroiditis with primary hypogonadism) and in three men with IgGSD/SPAD (two with either mild GHD or secondary hypothyroidism combined with secondary hypogonadism, and one man with secondary AI and severe GHD). Genetic testing in a subset of patients did not reveal pathogenic variants in NFKB2 or other known PID-associated genes. Conclusion: This is the first study to describe a high prevalence of both anterior pituitary and end-organ endocrine dysfunction in adult PAD patients. As these endocrine disorders may cause considerable health burden, assessment of endocrine axes should be considered in PAD patients
An electrophysiological investigation of co-referential processes in visual narrative comprehension
Visual narratives make use of various means to convey referential and co-referential meaning, so comprehenders must recognize that different depictions across sequential images represent the same character(s). In this study, we investigated how the order in which different types of panels in visual sequences are presented affects how the unfolding narrative is comprehended. Participants viewed short comic strips while their electroencephalogram (EEG) was recorded. We analyzed evoked and induced EEG activity elicited by both full panels (showing a full character) and refiner panels (showing only a zoom of that full panel), and took into account whether they preceded or followed the panel to which they were co-referentially related (i.e., were cataphoric or anaphoric). We found that full panels elicited both larger N300 amplitude and increased gamma-band power compared to refiner panels. Anaphoric panels elicited a sustained negativity compared to cataphoric panels, which appeared to be sensitive to the referential status of the anaphoric panel. In the time-frequency domain, anaphoric panels elicited reduced 8-12 Hz alpha power and increased 45-65 Hz gamma-band power compared to cataphoric panels. These findings are consistent with models in which the processes involved in visual narrative comprehension partially overlap with those in language comprehension
Hierarchical structure in language and action: A formal comparison
Since the cognitive revolution, language and action have been compared as cognitive systems, with cross-domain convergent views recently gaining renewed interest in biology, neuroscience, and cognitive science. Language and action are both combinatorial systems whose mode of combination has been argued to be hierarchical, combining elements into constituents of increasingly larger size. This structural similarity has led to the suggestion that they rely on shared cognitive and neural resources. In this paper, we compare the conceptual and formal properties of hierarchy in language and action using tools from category theory. We show that the strong compositionality of language requires a formalism that describes the mapping between sentences and their syntactic structures as an order-embedded Galois connection, while the weak compositionality of actions only requires a monotonic mapping between action sequences and their goals, which we model as a monotone Galois connection. We aim to capture the different system properties of language and action in terms of the distinction between hierarchical sets and hierarchical sequences, and discuss the implications for the way both systems are represented in the brain