Chronic E. Coli Drug-Resistant Cystitis Treated with a Sequence of Modulated Extremely Low-Frequency Electromagnetic Fields: A Randomized Study of 148 Cases

(1) Background: This study investigated the effects of sequenced electromagnetic fields, modulated at extremely low frequencies and intensities, in the treatment of drug-resistant Escherichia coli (E. coli)-induced chronic bacterial cystitis. (2) Methods: A total of 148 female participants, aged 18 to 80 years diagnosed with chronic bacterial cystitis caused by drug-resistant E. coli, were recruited for this study. Participants were randomly assigned to two groups: an experimental group (n = 74) with osteopathic palpation and assessment treated with a sequence of electromagnetic fields, and a control group (n = 74) receiving a placebo treatment. Both groups were assessed at this study's outset, 4 weeks after eight applications, and at 12 weeks for symptomatic presentation and laboratory parameters. (3) Results: After 4 weeks of treatment, a significant difference was observed between the two groups regarding D-DIMER levels, IL-6 levels, erythrocyte levels, leukocyte levels, and E. coli levels (p < 0.001). By the 12th week, the experimental group continued to exhibit a significant reduction in the examined parameters compared to the control group (p < 0.001). Additionally, the treatment did not induce any side effects in the patients in the experimental group. (4) Conclusions: Treatment with coherently sequenced electromagnetic fields, modulated at an extremely low frequency and intensity, not only appears to provide an effective alternative for the symptoms of chronic bacterial cystitis caused by drug-resistant E. coli but also demonstrates a potent antibacterial effect.

Pressure ulcers after prone positioning in patients undergoing extracorporeal membrane oxygenation: A cross-sectional study

BACKGROUND

The combination of prone positioning and extracorporeal membrane oxygenation (ECMO) in patients with acute respiratory distress syndrome (ARDS) is recognized as safe but its use has been limited due to potential complications.

AIM

To report the prevalence of pressure ulcers and other complications due to prone positioning in adult patients receiving veno-venous ECMO.

STUDY DESIGN

This cross-sectional study was conducted in a tertiary level intensive care unit (ICU) in Milan (Italy), between January 2015 and December 2019. The study population was critically ill adult patients undergoing veno-venous ECMO. Statistical association between pressure ulcers and the type of body positioning (prone versus supine) was explored fitting a logistic model.

RESULTS

In the study period, 114 patients were treated with veno-venous ECMO and 62 (54.4%) patients were placed prone for a total of 130 prone position cycles. ECMO cannulation was performed via femoro-femoral configuration in the majority of patients (82.4%, 94/114). Pressure ulcers developed in 57.0% of patients (95%CI: 44.0%-72.6%), most often arising on the face and the chin (37.1%, 23/62), particularly in those placed prone. The main reason of prone positioning interruption was the decrease of ECMO blood flow (8.1%, 5/62). The fitted model showed no association between body position during ECMO and occurrence of pressure ulcers (OR 1.3, 95%CI: 0.5-3.6, p = .532).

CONCLUSIONS

Facial pressure ulcers were the most frequent complications of prone positioning. Nurses should plan and implement evidence-based care to prevent such pressure injuries in patients undergoing ECMO.

RELEVANCE TO CLINICAL PRACTICE

The combination of prone positioning and ECMO shows few life-threating complications. This manoeuvre during ECMO is feasible and safe when performed by experienced ICU staff.

Selenoprotein deficiency disorder predisposes to aortic aneurysm formation

Aortic aneurysms, which may dissect or rupture acutely and be lethal, can be a part of multisystem disorders that have a heritable basis. We report four patients with deficiency of selenocysteine-containing proteins due to selenocysteine Insertion Sequence Binding Protein 2 (SECISBP2) mutations who show early-onset, progressive, aneurysmal dilatation of the ascending aorta due to cystic medial necrosis. Zebrafish and male mice with global or vascular smooth muscle cell (VSMC)-targeted disruption of Secisbp2 respectively show similar aortopathy. Aortas from patients and animal models exhibit raised cellular reactive oxygen species, oxidative DNA damage and VSMC apoptosis. Antioxidant exposure or chelation of iron prevents oxidative damage in patient's cells and aortopathy in the zebrafish model. Our observations suggest a key role for oxidative stress and cell death, including via ferroptosis, in mediating aortic degeneration.

Short-Term Exposure to Benzo(a)Pyrene Causes Disruption of GnRH Network in Zebrafish Embryos

Benzo(a)pyrene (BaP), a polycyclic aromatic hydrocarbon, is considered a common endocrine disrupting chemical (EDC) with mutagenic and carcinogenic effects. In this work, we evaluated the effects of BaP on the hypothalamo-pituitary-gonadal axis (HPG) of zebrafish embryos. The embryos were treated with 5 and 50 nM BaP from 2.5 to 72 hours post-fertilization (hpf) and obtained data were compared with those from controls. We followed the entire development of gonadotropin releasing hormone (GnRH3) neurons that start to proliferate from the olfactory region at 36 hpf, migrate at 48 hpf and then reach the pre-optic area and the hypothalamus at 72 hpf. Interestingly, we observed a compromised neuronal architecture of the GnRH3 network after the administration of 5 and 50 nM BaP. Given the toxicity of this compound, we evaluated the expression of genes involved in antioxidant activity, oxidative DNA damage and apoptosis and we found an upregulation of these pathways. Consequently, we performed a TUNEL assay and we confirmed an increment of cell death in brain of embryos treated with BaP. In conclusion our data reveal that short-term exposure of zebrafish embryos to BaP affects GnRH3 development likely through a neurotoxic mechanism.

Defective jagged-1 signaling affects GnRH development and contributes to congenital hypogonadotropic hypogonadism

In vertebrate species, fertility is controlled by gonadotropin-releasing hormone (GnRH) neurons. GnRH cells arise outside the central nervous system, in the developing olfactory pit, and migrate along olfactory/vomeronasal/terminal nerve axons into the forebrain during embryonic development. Congenital hypogonadotropic hypogonadism (CHH) and Kallmann syndrome are rare genetic disorders characterized by infertility, and they are associated with defects in GnRH neuron migration and/or altered GnRH secretion and signaling. Here, we documented the expression of the jagged-1/Notch signaling pathway in GnRH neurons and along the GnRH neuron migratory route both in zebrafish embryos and in human fetuses. Genetic knockdown of the zebrafish ortholog of JAG1 (jag1b) resulted in altered GnRH migration and olfactory axonal projections to the olfactory bulbs. Next-generation sequencing was performed in 467 CHH unrelated probands, leading to the identification of heterozygous rare variants in JAG1. Functional in vitro validation of JAG1 mutants revealed that 7 out of the 9 studied variants exhibited reduced protein levels and altered subcellular localization. Together our data provide compelling evidence that Jag1/Notch signaling plays a prominent role in the development of GnRH neurons, and we propose that JAG1 insufficiency may contribute to the pathogenesis of CHH in humans.

Short-Term Exposure Effects of the Environmental Endocrine Disruptor Benzo(a)Pyrene on Thyroid Axis Function in Zebrafish

Benzo(a)Pyrene (BaP) is one of the most widespread polycyclic aromatic hydrocarbons (PAHs) with endocrine disrupting properties and carcinogenic effects. In the present study, we tested the effect of BaP on thyroid development and function, using zebrafish as a model system. Zebrafish embryos were treated with 50 nM BaP from 2.5 to 72 h post fertilization (hpf) and compared to 1.2% DMSO controls. The expression profiles of markers of thyroid primordium specification, thyroid hormone (TH) synthesis, hypothalamus-pituitary-thyroid (HPT) axis, TH transport and metabolism, and TH action were analyzed in pools of treated and control embryos at different developmental stages. BaP treatment did not affect early markers of thyroid differentiation but resulted in a significant decrease of markers of TH synthesis (tg and nis) likely secondary to defective expression of the central stimulatory hormones of thyroid axis (trh, tshba) and of TH metabolism (dio2). Consequently, immunofluorescence of BaP treated larvae showed a low number of follicles immunoreactive to T4. In conclusion, our results revealed that the short-term exposure to BaP significantly affects thyroid function in zebrafish, but the primary toxic effects would be exerted at the hypothalamic-pituitary level thus creating a model of central hypothyroidism.

Clinical Consequences of Variable Results in the Measurement of Free Thyroid Hormones: Unusual Presentation of a Family with a Novel Variant in the THRB Gene Causing Resistance to Thyroid Hormone Syndrome

INTRODUCTION

Resistance to thyroid hormone β (RTHβ) is an inherited syndrome caused by dominant negative variants in the THRB gene (NM_000461.5). The clinical picture of RTHβ is variable, and patients harboring the same variant may display different degrees of disease severity.

CASE PRESENTATION

A 30-year-old man presented with thyrotoxicosis and central hyperthyroidism and was found to have a novel variant in the exon 10 of THRB gene (c.C1282G, p.L428V), located within the third hot spot region of the C-terminal of the receptor. Surprisingly, the same variant was found in two other relatives with an apparent normal thyroid function at initial screening. After exclusion of a TSH-secreting adenoma and serum interference in the proband, and the finding that exogenous levothyroxine failed to suppress the TSH in the brother affected by nodular goiter, relatives' thyroid function tests (TFTs) were reassessed with additional analytical method revealing biochemical features consistent with RTHβ in all carriers of the p.L428V variant. Functional studies showed a slightly impaired in vitro transcriptional activity of p.L428V. Interestingly' the expression of the human p.L428V thyroid hormone receptor beta in the zebrafish embryo background generated a phenotype consistent with RTHβ.

CONCLUSION

Variable results of TFTs on some immunoassays can be a cause of RTHβ diagnostic delay, but the genotype-phenotype correlation in this family and functional studies support p.L428V as a novel THRB variant expanding the spectrum of gene variants causing RTHβ. In vivo, rather than in vitro, functional assays may be required to demonstrate the dominant negative action of THRB variants.

From Endoderm to Progenitors: An Update on the Early Steps of Thyroid Morphogenesis in the Zebrafish

The mechanisms underlying thyroid gland development have a central interest in biology and this review is aimed to provide an update on the recent advancements on the early steps of thyroid differentiation that were obtained in the zebrafish, because this teleost fish revealed to be a suitable organism to study the early developmental stages. Physiologically, the thyroid precursors fate is delineated by the appearance among the endoderm cells of the foregut of a restricted cell population expressing specific transcription factors, including pax2a, nkx2.4b, and hhex. The committed thyroid primordium first appears as a thickening of the pharyngeal floor of the anterior endoderm, that subsequently detaches from the floor and migrates to its final location where it gives rise to the thyroid hormone-producing follicles. At variance with mammalian models, thyroid precursor differentiation in zebrafish occurs early during the developmental process before the dislocation to the eutopic positioning of thyroid follicles. Several pathways have been implicated in these early events and nowadays there is evidence of a complex crosstalk between intrinsic (coming from the endoderm and thyroid precursors) and extrinsic factors (coming from surrounding tissues, as the cardiac mesoderm) whose organization in time and space is probably required for the proper thyroid development. In particular, Notch, Shh, Fgf, Bmp, and Wnt signaling seems to be required for the commitment of endodermal cells to a thyroid fate at specific developmental windows of zebrafish embryo. Here, we summarize the recent findings produced in the various zebrafish experimental models with the aim to define a comprehensive picture of such complicated puzzle.

Complications of prone positioning in patients with COVID-19: A cross-sectional study

OBJECTIVE

To determine the prevalence of complications in patients with COVID-19 undergone prone positioning, focusing on the development of prone-related pressure ulcers.

METHODS

Cross-sectional study conducted in the hub COVID-19 centre in Milan (Italy), between March and June 2020. All patients with COVID-19 admitted to intensive care unit on invasive mechanical ventilation and treated with prone positioning were included. Association between prone-related pressure ulcers and selected variables was explored by the means of logistic regression.

RESULTS

A total of 219 proning cycles were performed on 63 patients, aged 57.6 (10.8) and predominantly obese males (66.7%). The main complications recorded were: prone-related pressure ulcers (30.2%), bleeding (25.4%) and medical device displacement (12.7%), even if no unplanned extubation was recorded. The majority of patients (17.5%) experienced bleeding of upper airways. Only 15 prone positioning cycles (6.8%) were interrupted, requiring staff to roll the patient back in the supine position. The likelihood of pressure ulcers development was independently associated with the duration of prone positioning, once adjusting for age, hypoxemic level, and nutritional status (OR 1.9, 95%CI 1.04-3.6).

CONCLUSION

The use of prone positioning in patients with COVID-19 was a safe and feasible treatment, also in obese patients, who might deserve more surveillance and active prevention by intensive care unit staff.

Nursing Management of Prone Positioning in Patients With COVID-19

BACKGROUND

At the height of the coronavirus disease 2019 (COVID-19) pandemic, Italy had the highest number of deaths in Europe; most occurred in the Lombardy region. Up to 4% of patients with COVID-19 required admission to an intensive care unit because they developed a critical illness (eg, acute respiratory distress syndrome). Numerous patients with acute respiratory distress syndrome who had been admitted to the intensive care unit required rescue therapy like prone positioning.

OBJECTIVE

To describe the respiratory management of and the extensive use of prone positioning in patients with COVID-19 at the intensive care unit hub in Lombardy, Italy.

METHODS

A total of 89 patients (67% male; median age, 59 years [range, 23-80 years]) with confirmed COVID-19 who were admitted between February 23 and March 31, 2020, were enrolled in this quality improvement project.

RESULTS

Endotracheal intubation was required in 86 patients (97%). Prone positioning was used as rescue therapy in 43 (48%) patients. Significantly more younger patients (age ≤ 59 years) were discharged alive (43 of 48 [90%]) than were older patients (age ≥ 60 years; 26 of 41 [63%]; P < .005). Among the 43 patients treated with prone ventilation, 15 (35% [95% CI, 21%-51%]) died in the intensive care unit, of which 10 (67%; P < .001) were older patients.

CONCLUSIONS

Prone positioning is one strategy available for treating acute respiratory distress syndrome in patients with COVID-19. During this pandemic, prone positioning can be used extensively as rescue therapy, per a specific protocol, in intensive care units.

LGR4 deficiency results in delayed puberty through impaired Wnt/β-catenin signaling

The initiation of puberty is driven by an upsurge in hypothalamic gonadotropin-releasing hormone (GnRH) secretion. In turn, GnRH secretion upsurge depends on the development of a complex GnRH neuroendocrine network during embryonic life. Although delayed puberty (DP) affects up to 2% of the population, is highly heritable, and is associated with adverse health outcomes, the genes underlying DP remain largely unknown. We aimed to discover regulators by whole-exome sequencing of 160 individuals of 67 multigenerational families in our large, accurately phenotyped DP cohort. LGR4 was the only gene remaining after analysis that was significantly enriched for potentially pathogenic, rare variants in 6 probands. Expression analysis identified specific Lgr4 expression at the site of GnRH neuron development. LGR4 mutant proteins showed impaired Wnt/β-catenin signaling, owing to defective protein expression, trafficking, and degradation. Mice deficient in Lgr4 had significantly delayed onset of puberty and fewer GnRH neurons compared with WT, whereas lgr4 knockdown in zebrafish embryos prevented formation and migration of GnRH neurons. Further, genetic lineage tracing showed strong Lgr4-mediated Wnt/β-catenin signaling pathway activation during GnRH neuron development. In conclusion, our results show that LGR4 deficiency impairs Wnt/β-catenin signaling with observed defects in GnRH neuron development, resulting in a DP phenotype.

Defects of LGR4/Wnt-β-catenin activity compromise the development of the GnRH neuroendocrine network, resulting in delayed onset of puberty in humans and mice.

Glis3 as a Critical Regulator of Thyroid Primordium Specification

Background: GLIS3 (GLI-Similar protein 3) is a transcription factor involved in several cellular processes. Homozygous mutations in the GLIS3 gene have been typically associated with neonatal diabetes and congenital hypothyroidism (CH) in a syndrome called NDH. NDH patients present developmental abnormalities including endocrine pancreas defects and a spectrum of thyroid abnormalities, mainly including thyroid dysgenesis (TD). The mouse models revealed a key role of Glis3 in pancreatic islets but not in early thyroid development, as Glis3 was described to retain a role in regulating thyroid hormone synthesis downstream the thyrotropin (TSH)/TSHR signaling pathway and in postnatal follicle proliferation. Hence, in this study, we have been taking advantage of the zebrafish model to gain insights on the Glis3 activity during thyroid organogenesis. Methods: Transient glis3-knockdown zebrafish embryos (called glis3 morphants) were generated by the microinjection of specific glis3 morpholinos at one- to two-cell stage to analyze the thyroid phenotype in vivo. Several additional analyses (in situ hybridization, immunohistochemistry, and pharmacological treatments) were performed for further molecular characterization. Results: The analysis of thyroid embryonic development revealed that Glis3 is involved in early steps of thyroid specification. glis3 morphants exhibited a reduced expression of the early transcription factors nkx2.4 and pax2a at the thyroid primordium level, which is not caused by changes in proliferation or apoptosis of the pharyngeal endoderm. As a result, the differentiated thyroid tissue in morphants appeared reduced in size with decreased expression of tg and slc5a5, a low number of thyroxine (T4)-producing follicles, associated with an elevation of tshba (homologous of the human TSHβ), thus resembling the clinical and biochemical manifestations of patients with TD. Interestingly, glis3 morphants have pancreatic β-cell defects, but not liver defects. In vitro and in vivo data also demonstrated that Glis3 is an effector of the Sonic Hedgehog (SHH) pathway. Molecular and pharmacological inhibition of SHH reproduced the thyroid defects observed in glis3 morphant. Conclusions: Our results demonstrate that glis3, within the SHH pathway, appears to determine the number of endodermal cells committed to a thyroid fate. This is the first evidence of the involvement of Glis3 in TD, thereby expanding the understanding of the genetic basis of thyroid development and CH.

Thyroid Hormone Hyposensitivity: From Genotype to Phenotype and Back

Thyroid hormone action defects (THADs) have been classically considered conditions of impaired sensitivity to thyroid hormone (TH). They were originally referring to alterations in TH receptor genes (THRA and THRB), but the discovery of genetic mutations and polymorphisms causing alterations in cell membrane transport (e.g., MCT8) and metabolism (e.g., SECISBP2, DIO2) led recently to a new and broader definition of TH hyposensitivity (THH), including not only THADs but all defects that could interfere with the activity of TH. Due to the different functions and tissue-specific expression of these genes, affected patients exhibit highly variable phenotypes. Some of them are characterized by a tissue hypothyroidism or well-recognizable alterations in the thyroid function tests (TFTs), whereas others display a combination of hypo- and hyperthyroid manifestations with normal or only subtle biochemical defects. The huge effort of basic research has greatly aided the comprehension of the molecular mechanisms underlying THADs, dissecting the morphological and functional alterations on target tissues, and defining the related-changes in the biochemical profile. In this review, we describe different pictures in which a specific alteration in the TFTs (TSH, T4, and T3 levels) is caused by defects in a specific gene. Altogether these findings can help clinicians to early recognize and diagnose THH and to perform a more precise genetic screening and therapeutic intervention. On the other hand, the identification of new genetic variants will allow the generation of cell-based and animal models to give novel insight into thyroid physiology and establish new therapeutic interventions.

Role of TRs in Zebrafish Development

In recent years, the zebrafish has become a powerful model not only for the developmental biology studies, but also for genetic analyses and drug screenings, mostly thanks to the ease with which its embryos can be manipulated and to its translucent body, which allows in vivo imaging. In this chapter, we will provide an overview of the current knowledge about the role of thyroid hormone receptors during zebrafish embryonic development. Moreover, we will explore the methodologies applied to zebrafish biology to knock down a gene of interest and to analyze in vivo the molecular mechanisms of the mutated receptors.

Role of Jagged1-Notch pathway in thyroid development

The zebrafish thyroid gland shows a unique pattern of growth. Despite the lack of a compact gland, the zebrafish thyroid tissue originates from the pharyngeal endoderm and the main genes involved in its patterning and early development are conserved between zebrafish and mammals. In recent years, the research has been focused to the search of novel candidate genes and environmental factors underlying congenital hypothyroidism. Among these, it has been demonstrated that the Notch signalling plays a central role during zebrafish thyroid development. In this review, we will provide an overview of the current knowledge of the distinct roles of the Notch signalling and of the jag1a and jag1b ligands during the different phases of thyroid organogenesis. Furthermore, we will discuss the role of JAG1 variants in congenital thyroid defects.

GLIS3 and Thyroid: A Pleiotropic Candidate Gene for Congenital Hypothyroidism

Variations in the transcription factor Gli-similar 3 (GLIS3) gene have been associated to variable congenital endocrine defects, including both morphogenetic and functional thyroid alterations. Evidence from Glis3 knockout mice indicates a relevant role for GLIS3 in thyroid hormone biosynthesis and postnatal thyroid gland growth, with a mechanism of action downstream of the TSH/TSHR interaction. However, the pathophysiological role of this transcription factor during the embryonic thyroid development remains unexplored. In this manuscript, we will provide an overview of the current knowledge on GLIS3 function during development. As a perspective, we will present preliminary evidence in the zebrafish model in support of a potential role for this pleiotropic transcription factor in the early stages of thyroid gland development.

How zebrafish research has helped in understanding thyroid diseases

Next-generation sequencing technologies have revolutionized the identification of disease-causing genes, accelerating the discovery of new mutations and new candidate genes for thyroid diseases. To face this flow of novel genetic information, it is important to have suitable animal models to study the mechanisms regulating thyroid development and thyroid hormone availability and activity. Zebrafish ( Danio rerio), with its rapid external embryonic development, has been extensively used in developmental biology. To date, almost all of the components of the zebrafish thyroid axis have been characterized and are structurally and functionally comparable with those of higher vertebrates. The availability of transgenic fluorescent zebrafish lines allows the real-time analysis of thyroid organogenesis and its alterations. Transient morpholino-knockdown is a solution to silence the expression of a gene of interest and promptly obtain insights on its contribution during the development of the zebrafish thyroid axis. The recently available tools for targeted stable gene knockout have further increased the value of zebrafish to the study of thyroid disease. All of the reported zebrafish models can also be used to screen small compounds and to test new drugs and may allow the establishment of experimental proof of concept to plan subsequent clinical trials.

A frequent oligogenic involvement in congenital hypothyroidism

Congenital hypothyroidism (CH), the most frequent form of preventable mental retardation, is predicted to have a relevant genetic origin. However, CH is frequently reported to be sporadic and candidate gene variations were found in <10% of the investigated patients. Here, we characterize the involvement of 11 candidate genes through a systematic Next Generation Sequencing (NGS) analysis. The NGS was performed in 177 unrelated CH patients (94 gland-in-situ; 83 dysgenesis) and in 3,538 control subjects. Non-synonymous or splicing rare variants (MAF < 0.01) were accepted, and their functional impact was predicted by a comprehensive bioinformatic approach and co-segregation studies. The frequency of variations in cases and controls was extended to 18 CH-unrelated genes. At least one rare variant was accepted in 103/177 patients. Monogenic recessive forms of the disease were found in five cases, but oligogenic involvement was detected in 39 patients. The 167 variations were found to affect all genes independently of the CH phenotype. These findings were replicated in an independent cohort of additional 145 CH cases. When compared to 3,538 controls, the CH population was significantly enriched with disrupting variants in the candidate genes (P = 5.5 × 10-7), but not with rare variations in CH-unrelated genes. Co-segregation studies of the hypothyroid phenotype with multiple gene variants in several pedigrees confirmed the potential oligogenic origin of CH. The systematic NGS approach reveals the frequent combination of rare variations in morphogenetic or functional candidate genes in CH patients independently of phenotype. The oligogenic origin represents a suitable explanation for the frequent sporadic CH occurrence.

In vivo Functional Consequences of Human THRA Variants Expressed in the Zebrafish

BACKGROUND

Heterozygous mutations in the thyroid hormone receptor alpha (THRA) gene cause resistance to thyroid hormone alpha (RTHα), a disease characterized by variable manifestations reminiscent of untreated congenital hypothyroidism but a raised triiodothyronine/thyroxine ratio and normal thyrotropin levels. It was recently described that zebrafish embryos expressing a dominant negative (DN) form of thraa recapitulate the key features of RTHα, and that zebrafish and human receptors are functionally interchangeable.

METHODS

This study expressed several human thyroid hormone receptor alpha (hTRα) variants in zebrafish embryos and analyzed the resulting phenotypes.

RESULTS

All hTRα-injected embryos showed variable defects, including cerebral and cardiac edema likely caused by an aberrant looping during heart development, anemia, and an incomplete formation of the vascular network. Moreover, the hTRα-injected embryos presented severe defects of motorneurons and craniofacial development, thus affecting their autonomous feeding and swimming behaviors. Surprisingly, expression of all hTRα mutants had no detectable effect on thyrotropin beta and thyrotropin-releasing hormone transcripts, indicating that their DN action is limited on the thyroid hormone reception beta 2 targets at the hypothalamic/pituitary level in vivo. As previously described in vitro, treatment with high triiodothyronine doses can efficiently revert the observed defects only in embryos injected with missense hTRα variants.

CONCLUSION

Injection of human THRA variants in zebrafish embryos causes tissue-specific defects recapitulating most of the RTHα clinical and biochemical manifestations. The described manipulation of zebrafish embryos represents a novel in vivo model to screen the functional consequences of THRA variants and the rescue potential of new therapeutic compounds.

Manual evaluation of the diaphragm muscle

The respiratory diaphragm is the most important muscle for breathing. It contributes to various processes such as expectoration, vomiting, swallowing, urination, and defecation. It facilitates the venous and lymphatic return and helps viscera located above and below the diaphragm to work properly. Its activity is fundamental in the maintenance of posture and body position changes. It can affect the pain perception and emotional state. Many authors reported on diaphragmatic training by using special instruments, whereas only a few studies focused on manual therapy approaches. To the knowledge of the authors, the existing scientific literature does not exhaustively examines the manual evaluation of the diaphragm in its different portions. A complete evaluation of the diaphragm is mandatory for several professional subjects, such as physiotherapists, osteopaths, and chiropractors not only to elaborate a treatment strategy but also to obtain information on the validity of the training performed on the patient. This article aims to describe a strategy of manual evaluation of the diaphragm, with particular attention to anatomical fundamentals, in order to stimulate further research on this less explored field.

The zebrafish: an emerging animal model for investigating the hypothalamic regulation of reproduction

Gonadotropin-releasing hormone (GnRH) neurons have a pivotal role in the physiological functions of hypotahlamic-pituitary-gonadal (HPG) axis. The pulsatile releasing of GnRH hormone into the hypophyseal portal circulation at the median eminence represent the first domino in the HPG cascade of events that regulate the development, fertility and aging in all vertebrates. These neurons principally originate in the olfactory placode and migrate during early embryonal stages into the hypothalamus. Alterations in developmental processes or in the releasing of GnRH hormone lead to a rare and complex disorder of the reproductive axis called congenital hypogonadotropic hypogonadism (CHH). Genetic screening of human patients and the use of model systems have led to the identification of several genes involved in the CHH pathogenesis underlying its oligogenic nature. Nevertheless CHH remains, for a large cohort of patients, idiopathic and GnRH neurogenesis processes not fully understood. This is due to intrinsic difficulties that exist in the analysis of earliest embryonic developmental stages and in the methodologies developed to study the CHH-causing genes. In this regard, zebrafish embryos, on account of its external fertilization and development, allow a real-time analysis that could overcome some of the above mentioned limitations. Moreover, the recent availability of several transgenic zebrafish reporter lines makes it an excellent model for the study of the oligogenic mechanisms leading to CHH.

Patterns of thyroid hormone receptor expression in zebrafish and generation of a novel model of resistance to thyroid hormone action

Resistance to thyroid hormone can be due to heterozygous, dominant negative (DN) THRA (RTHα) or THRB (RTHβ) mutations, but the underlying mechanisms are incompletely understood. Here, we delineate the spatiotemporal expression of TH receptors (TRs) in zebrafish and generated morphants expressing equivalent amounts of wild-type and DN TRαs (thraa_MOs) and TRβs (thrb_MOs) in vivo. Both morphants show severe developmental abnormalities. The phenotype of thraa_MOs includes brain and cardiac defects, but normal thyroid volume and tshba expression. A combined modification of dio2 and dio3 expression can explain the high T3/T4 ratio seen in thraa_MOs, as in RTHα. Thrb_MOs show abnormal eyes and otoliths, with a typical RTHβ pattern of thyroid axis. The coexpression of wild-type, but not mutant, human TRs can rescue the phenotype in both morphants. High T3 doses can partially revert the dominant negative action of mutant TRs in morphant fish. Therefore, our morphants recapitulate the RTHα and RTHβ key manifestations representing new models in which the functional consequences of human TR mutations can be rapidly and faithfully evaluated.

JAG1 Loss-Of-Function Variations as a Novel Predisposing Event in the Pathogenesis of Congenital Thyroid Defects

CONTEXT

The pathogenesis of congenital hypothyroidism (CH) is still largely unexplained. We previously reported that perturbations of the Notch pathway and knockdown of the ligand jagged1 cause a hypothyroid phenotype in the zebrafish. Heterozygous JAG1 variants are known to account for Alagille syndrome type 1 (ALGS1), a rare multisystemic developmental disorder characterized by variable expressivity and penetrance.

OBJECTIVE

Verify the involvement of JAG1 variants in the pathogenesis of congenital thyroid defects and the frequency of unexplained hypothyroidism in a series of ALGS1 patients.

DESIGN, SETTINGS, AND PATIENTS

A total of 21 young ALGS1 and 100 CH unrelated patients were recruited in academic and public hospitals. The JAG1 variants were studied in vitro and in the zebrafish.

RESULTS

We report a previously unknown nonautoimmune hypothyroidism in 6/21 ALGS1 patients, 2 of them with thyroid hypoplasia. We found 2 JAG1 variants in the heterozygous state in 4/100 CH cases (3 with thyroid dysgenesis, 2 with cardiac malformations). Five out 7 JAG1 variants are new. Different bioassays demonstrate that the identified variants exhibit a variable loss of function. In zebrafish, the knock-down of jag1a/b expression causes a primary thyroid defect, and rescue experiments of the hypothyroid phenotype with wild-type or variant JAG1 transcripts support a role for JAG1 variations in the pathogenesis of the hypothyroid phenotype seen in CH and ALGS1 patients.

CONCLUSIONS

clinical and experimental data indicate that ALGS1 patients have an increased risk of nonautoimmune hypothyroidism, and that variations in JAG1 gene can contribute to the pathogenesis of variable congenital thyroid defects, including CH.

The fascial system and exercise intolerance in patients with chronic heart failure: hypothesis of osteopathic treatment

Chronic heart failure is a progressive, debilitating disease, resulting in a decline in the quality of life of the patient and incurring very high social economic costs. Chronic heart failure is defined as the inability of the heart to meet the demands of oxygen from the peripheral area. It is a multi-aspect complex disease which impacts negatively on all of the body systems. Presently, there are no texts in the modern literature that associate the symptoms of exercise intolerance of the patient with a dysfunction of the fascial system. In the first part of this article, we will discuss the significance of the disease, its causes, and epidemiology. The second part will explain the pathological adaptations of the myofascial system. The last section will outline a possible osteopathic treatment for patients with heart failure in order to encourage research and improve the general curative approach for the patient.

Novel NKX2-1 Frameshift Mutations in Patients with Atypical Phenotypes of the Brain-Lung-Thyroid Syndrome

OBJECTIVES

To verify the involvement of NKX2-1 gene in infants with brain-lung-thyroid (BLT) syndrome and hypothyroid phenotypes variable among congenital hypothyroidism (CH) or idiopathic mild hypothyroidism (IMH) of postnatal onset.

METHODS

The candidates were selected by a case-finding approach in 130 CH and 53 IMH infants. The NKX2-1 gene was analyzed by direct sequencing and multiplex ligation-dependent probe amplification. The variants were studied in vitro, by expression analyses and luciferase bioassay.

RESULTS

Four cases (3 CH and 1 IMH) consistent with BLT syndrome were identified. Two children were affected with respiratory distress and CH, but wild-type NKX2-1 gene. The remaining two presented choreic movements and no pulmonary involvement, but discrepant thyroid phenotypes: one had severe CH with lingual ectopy and the other one IMH with gland in situ. They were carriers of new de novo heterozygous frameshift mutations of NKX2-1 (c.177delG and c.153_166del14). The c.177delG leads to a prematurely truncated protein (p.H60TfsX11) with undetectable activity in vitro. The c.153_166del14 leads to the generation of an elongated aberrant protein (p.A52RfsX351) able to translocate into the nucleus, but completely inactive on a responsive promoter.

CONCLUSIONS

Two novel heterozygous frameshift mutations of NKX2-1 were identified in 2 cases selected on the basis of a BLT-like phenotype among 183 hypothyroid infants. The atypical hypothyroid phenotypes of these 2 children (CH with lingual ectopy or IMH of postnatal onset) further expand the clinical spectrum that can be associated with NKX2-1 mutations.

Disruptions of global and JAGGED1-mediated notch signaling affect thyroid morphogenesis in the zebrafish

The mechanisms underlying the early steps of thyroid development are largely unknown. In search for novel candidate genes implicated in thyroid function, we performed a gene expression analysis on thyroid cells revealing that TSH regulates the expression of several elements of the Notch pathway, including the ligand Jagged1. Because the Notch pathway is involved in cell-fate determination of several foregut-derived endocrine tissues, we tested its contribution in thyroid development using the zebrafish, a teleost model recapitulating the mammalian molecular events during thyroid development. Perturbing the Notch signaling (e.g. mib mutants, γ-secretase inhibition, or Notch intracellular domain overexpression), we obtained evidence that this pathway has a biological role during the earlier phases of thyroid primordium induction, limiting the number of cells that proceed to a specialized fate and probably involving actions from surrounding tissues. Moreover, we were able to confirm the expression of Jagged1 during different phases of zebrafish thyroid development, as well as in mouse and human thyroid tissues. The two orthologues to the single jagged1 gene (JAG1) in humans, jag1a and jag1b, are expressed with different spatiotemporal patterns in the developing zebrafish thyroid. Both jag1a and jag1b morphants, as well as jag1b mutant fish line, display thyroid hypoplasia and impaired T(4) production; this thyroid phenotype was rescued by coinjection of human JAG1 mRNA. In conclusion, Notch pathway is involved in the early steps of thyroid morphogenesis, and Jagged1-Notch signal is required for zebrafish thyroid development and function. Thus, genetic alterations affecting the Notch pathway may confer susceptibility for thyroid dysgenesis.

Frequent TSH receptor genetic alterations with variable signaling impairment in a large series of children with nonautoimmune isolated hyperthyrotropinemia

CONTEXT

Heterozygous mutations in the TSH receptor gene (TSHR) are associated with partial TSH resistance, characterized by isolated nonautoimmune hyperthyrotropinemia (NAHT). The prevalence and management of this condition is controversial.

OBJECTIVE

Our objective was to investigate the prevalence and clinical impact of TSHR alterations in a large series of pediatric patients with NAHT and to dissect their mechanism of action.

DESIGN AND SETTING

For this prospective multicenter study, clinical data and samples were collected in the clinical units and conveyed to a centralized laboratory for analysis.

PATIENTS

Subjects included 153 unrelated patients with NAHT aged <18 yr. Exclusion criteria included thyroid dysgenesis or major associated congenital defects.

MAIN OUTCOME MEASURES

Parameters of thyroid function, TSHR gene analysis, and TSHR functional assays were evaluated.

RESULTS

The frequency of heterozygous nonpolymorphic TSHR variations was 11.8%. We identified seven previously unknown variations: a frameshift (p.Q33PfsX46), one intronic (g.IVS4+2A→G), and five novel missense (p.P162L, p.Y466C, p.I583T, p.I607T, and p.R609Q) variations. The missense variations variably affected TSHR membrane expression and G(s) and/or G(q/11) signaling. Several variations cosegregated with NAHT in the affected families. Parameters of thyroid function were similar between affected and unaffected family members.

CONCLUSIONS

Nonpolymorphic alterations in the TSHR gene are commonly associated with isolated NAHT in young patients, thus configuring partial TSH resistance as the most frequent inheritable cause of isolated NAHT. The identification of TSHR defects may thus be helpful for a tailored management of subclinical hypothyroidism. We provide further evidence that besides the well-known defects in G(s) signaling, TSHR genetic alternations found in NAHT may frequently impair the G(q/11) pathway.

Increased risk for non-autoimmune hypothyroidism in young patients with congenital heart defects

CONTEXT

Newborns with congenital hypothyroidism (CH) have an increased risk for congenital heart defects (CHD) due to a common embryonic developmental program between thyroid gland and heart and great vessels.

OBJECTIVE

Our objective was to investigate the prevalence and origin of thyroid disorders in young patients with CHD.

DESIGN AND SETTING

We conducted a prospective observational study between January 2007 and January 2009 in academic Pediatric Cardiosurgery and Endocrinology.

PATIENTS

Patients included 324 children (164 males, 160 females, aged 0.2-15.4 yrs) with CHD.

INTERVENTION

Subjects underwent hormonal and genetic screening.

MAIN OUTCOME MEASURES

Serum TSH and thyroid hormone levels were assessed.

RESULTS

Two CHD patients were diagnosed with CH at the neonatal screening (1:162). Mild hypothyroidism (serum TSH > 4.0 μU/ml) was diagnosed and confirmed 6 months later [TSH = 5.4 ± 1.5 μU/ml; free T(4) = 1.3 ± 0.2 ng/dl (normal values 0.8-1.9)] in 37 children (11.5%) who were negative at neonatal screening. Hypothyroidism was not related to type of CHD, whereas TSH levels positively correlated with serum N-terminal pro-type B natriuretic peptide levels. Biochemical and ultrasound findings consistent with thyroid autoimmunity were present in three of 37 hypothyroid children (8.1%). One patient had hemiagenesis (2.7%). Variations in candidate genes were screened in CHD patients. NKX2.5 coding sequence was normal in all samples. A 3-Mb microdeletion in 22q11.2 was detected in three patients (8.3%), whereas only known polymorphisms were identified in TBX1 coding sequence.

CONCLUSIONS

CHD patients have an increased risk for both CH (10-fold higher) and acquired mild hypothyroidism (3-fold higher). Unrecognized mild hypothyroidism may negatively affect the outcome of CHD children, suggesting that thyroid function should be repeatedly checked. Thyroid autoimmunity and 22q11.2 microdeletions account for small percentages of these cases, and still unknown mechanisms underline such a strong association.

Syndromes of resistance to TSH

The resistance to TSH action is a genetic disease characterized by molecular defects hampering the adequate transmission of TSH stimulatory signal into thyroid cells. In principle the defect may affect every step along the cascade of events following the binding of TSH to its receptor (TSHR) on thyroid cell membranes. The phenotypic expressivity of TSH resistance is highly variable going from severe congenital hypothyroidism (CH) with thyroid hypoplasia to mild hyperthyrotropinemia (hyperTSH) associated with an apparent euthyroid state. More severe forms follow a recessive pattern of inheritance and occur in patients with biallelic mutations both causing a severe loss of TSHR function. Differential diagnosis in these cases includes the exclusions of other causes of isolated thyroid dysgenesis. Mildest forms may instead occur in patients with monoallelic TSHR defects following a dominant mode of inheritance. In these cases we described the dominant negative effect exerted by some mutants on the activity of the receptor encoded by the wild type allele. In these cases, differential diagnosis involves the exclusion of autoimmune thyroid disease or pseudohypoparathyroidism associated with defects at the GNAS locus. This review will focus on the variable clinical expression of this disease.

Biased TCR gene usage in alloreactive T cells specific for a structurally dissimilar MHC alloantigen

Two models of allorecognition of MHC molecules have been proposed. One emphasizes specificity for MHC molecule-bound peptides and the other for exposed MHC polymorphisms. We predicted that the latter model would predominate in responder:stimulator combinations whose MHC molecules differed extensively in their TCR-contacting surfaces and that this would be reflected in biased TCR usage. Two panels of anti-DR11 T cell clones were generated, one from a DR17 and the other from a DR15 responder. The TCR-contacting surfaces of DR17 and DR11 have multiple differences, and those of DR15 and DR11 are very similar. TCR analysis by polymerase chain reaction amplification and mAb staining revealed that five out of nine DR17 anti-DR11 clones used the V beta 13 and two the V beta 6, family. In contrast seven different V beta families were used by the eight DR15 anti-DR11 clones. A similar bias in TCR V beta usage was observed in the polyclonal DR17 and DR11 T cell lines from which the clones were derived, and in a second DR17 anti-DR11 line from a different individual. These results support the concept that specificity for the foreign MHC structure itself may play an important role in the alloresponse between responders and stimulators with structurally dissimilar MHC molecules.

Hepatitis C virus testing in primary biliary cirrhosis

We retrospectively investigated anti-HCV prevalence in a series of 160 consecutive patients with primary biliary cirrhosis who presented between 1980 and 1989. Of these, 19 (12%) were positive for anti-HCV by C-100 ELISA. Serum IgG levels were significantly higher in anti-HCV-positive patients and correlated to optical density values. A serum sample was again collected from all the patients from the same series who were seen in 1990 for follow-up, after a median period of 32 months. Anti-HCV positivity was found to be substantially unchanged in this subgroup of patients when the freshly drawn blood samples were retested with C-100 ELISA, while it increased from 10% to 17% when second generation ELISA was used. Three of the C-100 ELISA positive samples were C-100 RIBA reactive, and six of the second generation ELISA positive samples were 4-RIBA reactive. The HCV genome was not detected in any of the seven anti-HCV C-100 ELISA and second generation ELISA positive sera which were studied by polymerase chain reaction, including four cases confirmed by 4-RIBA. Life expectancy, as determined by survival analysis, did not differ significantly between anti-HCV-positive and -negative patients. These findings suggest that anti-HCV positivity does not influence the clinical presentation and course of primary biliary cirrhosis.

Antibodies to hepatitis C virus in primary biliary cirrhosis

We investigated the prevalence of anti-HCV in 160 consecutive patients with primary biliary cirrhosis. By ELISA, 19 (12%) were positive, as compared to a 68% prevalence in 135 patients with chronic non-A, non-B hepatitis. Serum IgG levels were significantly higher in the anti-HCV positive group. By RIBA, seropositivity was confirmed for 4 patients, whereas 7 were indeterminate. A slight, non-significant reduction of life expectancy was found in anti-HCV positive patients. Until reliable and independent confirmatory tests become available, definitive conclusions on the importance of anti-HCV positivity in primary biliary cirrhosis are improper.

CD1+ thymocytes proliferate and give rise to functional cells after stimulation with monoclonal antibodies recognizing CD3, CD2 or CD28 surface molecules

The signal requirements for activation and proliferation of CD1+ thymocytes have been studied in order to define whether this immature cell population could function as mature T cells do. We found that CD1+ cells expressed high levels of CD25 antigen upon triggering with specific monoclonal antibodies (mAbs) (anti-CD3, anti-CD2, anti-CD28) in association with low doses of Phorbol-13-myristate-12-acetate (PMA). More interestingly, we described that in the presence of PMA CD1+ thymocytes proliferate upon stimulation with anti-CD28 mAb as well as with a pair of anti-CD2 mAbs, without the need of exogenous interleukin-2 (IL2), whereas they respond to anti-CD3 mAb only if exogenous IL2 was provided. Furthermore, CD1+ cells stimulated under optimal proliferative conditions, gave rise to cell populations capable of lysing natural killer (NK)-sensitive (K562) and NK-resistant (MEL 10, Daudi, EPA1) tumor target cells. These data strongly support the idea that CD1+ thymocytes, under appropriate stimulations, display some of the functional capabilities of mature T cells.

[Factor VII and cardiovascular risk in obese subjects]

We investigated whether or not obesity is related to increased factor VII activity. We studied 70 obese subjects (aged 25 to 50 years, 25 males and 45 females, body mass index (BMI): mean +/- SD = 32.44 +/- 5.44) and 33 non-obese subjects (aged 25 to 50 years, 12 males and 21 females, BMI: mean +/- SD = 21.80 +/- 1.70). None of them were smokers or affected by hyperlipidemia, diabetes mellitus, impaired glucose tolerance or arterial hypertension. Factor VII activity was measured by the coagulometric method. We found higher factor VII activity in obese subjects (115.74 +/- 26.10%) than in healthy subjects (98.55 +/- 23.49%, p less than 0.005). Increased factor VII levels could determine a thrombophilic state involved in the genesis of cardiovascular accidents in obesity.

Simultaneous cytofluorometric analysis for the expression of cytoplasmic antigens and DNA content in CD3- human thymocytes

We describe a method of two-color immunofluorescence staining which allows the simultaneous analysis of both cytoplasmic antigens and cell entry into the S/G2/M cell cycle phases. This analysis was performed on CD3(-)-activated thymocytes obtained from either highly purified CD1-CD3-CD4-CD8- cells or fresh thymus cell suspensions, stimulated with low doses of phorbol-12 myristate-13 acetate (0.5 ng/ml) and interleukin-2. On the 14th day under these culture conditions about 90% of thymocytes did not express CD3 antigen on the cell surface. CD3- cells were further purified by cell sorting, fixed in paraformaldehyde, and permeabilized with Nonidet-P40. Then these thymocytes were stained by indirect immunofluorescence with monoclonal antibodies identifying T cell-specific molecules (CD3, CD2, CD28, TCR alpha/beta, and TCR gamma/delta) and analyzed for DNA content. Interestingly, both CD3 and CD28 antigens were detectable in the cytoplasm of most cells (greater than 80%). Further, the majority of the thymocytes which had entered the S/G2/M phases of the cell cycle (20%) expressed intracellular CD3 and CD28 molecules and reacted with the anti-beta framework beta F1 monoclonal antibody. The relationship between the appearance of CD3 and other T cell markers in the cytoplasm, the cell cycle entry, and the thymocyte development is discussed.