Sonographic Findings of Cervical Chondrocutaneous Branchial Remnants-A Comparison With Dermal Lesions/Cysts and a Literature Review: A Pilot Study.

OBJECTIVES: Cervical chondrocutaneous branchial remnants (CCBRs) and dermal lesions, such as epidermoid cysts or brachial anomalies, including lateral cervical cysts/sinuses or dermal sinuses of anterior chest lesions, are usually located at the lower neck at the anterior or posterior border of the sternocleidomastoid muscle (SCM). We aimed to demonstrate the usefulness of ultrasonography in the differential diagnosis and evaluation of CCBRs. METHODS: We evaluated 22 lesions of 20 pediatric patients, classified into CCBR and dermal lesion groups. We used Fisher's exact test to evaluate differences between these groups in terms of lesion shape (low-echoic mass- or tubular-like), whether the lesion was adjacent to/in contact with the SCM or not, and the presence or absence of a concave SCM caused by the lesion. RESULTS: Of the 22 lesions, 8 were CCBRs, and 14 were dermal lesions. We found a significant difference in the presence/absence of adjacency to or contact with the SCM (presence/absence of adjacency to or contact with the SCM in CCBRs vs that in dermal lesions: 6/2 vs 1/13, P = .002) and presence/absence of lesion-induced concavity of the SCM (presence/absence of lesion-induced concavity of the SCM in CCBRs vs that in dermal lesions: 3/5 vs 0/14, P = .036). The lesion shape (low-echoic mass-like/tubular-like lesions) did not significantly differ between the two study groups (low-echoic mass-like/tubular-like lesions in CCBRs vs that in dermal lesions: 5/3 vs 11/6, P = .624). CONCLUSIONS: CCBRs have a strong association with the SCM. These sonographic findings may be useful in the differential diagnosis of dermal cervical lesions.

Manga traqueal cartilaginosa. Reporte de dos casos / Tracheal cartilaginous sleeve. Report of two cases

La manga traqueal cartilaginosa es una malformación de la vía aérea donde no se distinguen anillos traqueales. Un segmento continuo de cartílago se extiende desde el cricoides, pudiendo llegar hasta los bronquios principales. Está asociada a síndromes de craneosinostosis con la mutación FGFR2, además de muertes prematuras por oclusión de la tráquea con tapones mucosos. Se presenta el curso clínico de pacientes portadores de manga traqueal cartilaginosa en el contexto de una malformación craneofacial. Caso 1. Masculino, al nacer hipoplasia del tercio medio facial. Polisomnografía: índice de apnea/hipopnea de 37,7/hr. Laringotraqueobroncoscopía (LTBC): tráquea sin anillos cartilaginosos desde cricoides hasta bronquios fuentes. Se indica traqueostomía. Caso 2. Masculino, al nacer cráneo en trébol. Poligrafía: Síndrome de apnea/hipopnea obstructiva del sueño (SAHOS) leve. Revisión vía aérea: desde subglotis hasta bronquios principales se extiende tráquea en manga. Se indica traqueostomía. En el contexto de una craneosinostosis en niños, especialmente con mutación FGFR2, creemos necesario realizar una LTBC en búsqueda de manga traqueal, ya que si es diagnosticada se debe recomendar traqueostomía, mejorando su expectativa de vida. Si la indicación de traqueostomía fuese por SAHOS, es obligatoria una LTBC preoperatoria, para evitar el no tener referencias anatómicas en el proceso.

A tracheal cartilaginous sleeve is a malformation of the airway in which the tracheal rings are indistinguishable. A continuous segment of cartilage extends from the cricoid, and it may reach all the way to the main bronchi. It is associated with various craniosynostosis syndromes with the FGFR2 mutation, in addition to premature deaths due to occlusions caused by mucus plugs in the trachea. Here we present the clinical course of patients who suffer from Tracheal Cartilaginous Sleeve in the context of a craniofacial malformation. First case. Male, presenting at birth a midfacial hypoplasia. Polysomnography: presents a 37,7/h index of apnea/hypopnea. Laryngotracheobronchoscopy (LTB): trachea is without cartilaginous rings from the cricoid to the main bronchi. A tracheostomy is indicated. Second case. Male, cloverleaf skull at birth. Polysomnography: Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) non-severe degree. Revision of the airway: the trachea in sleeve extends from the subglottis to the main bronchi. A tracheostomy is indicated. In the context of craniosynostosis in children, especially with FGFR2 mutation, we believe it is necessary to do an LTB in the search of a tracheal sleeve, since if it is diagnosed a tracheostomy must be indicated, to better the life expectancy of the patient. If the tracheostomy indication comes from an OSAHS, a preoperatory LTB is obligatory to avoid not having anatomical references during the procedure.

Complex Airway Management in Patients with Tracheal Cartilaginous Sleeves.

OBJECTIVES/HYPOTHESIS: A tracheal cartilaginous sleeve (TCS) is a rare anomaly characterized by anterior fusion of tracheal cartilages. TCS is associated with syndromic craniosynostoses including Apert, Crouzon and Pfeiffer syndromes and FGFR2, FGFR3, and TWIST1 variants. This study presents a 30-year review of patients with syndromic craniosynostosis and TCS and describes diagnostic methods, genetic variants, surgical interventions, and long-term outcomes. STUDY DESIGN: Retrospective, single-institution review. METHODS: This review included patients with syndromic craniosynostosis and TCS treated at Seattle Children's Hospital from 1990 to 2020. Tracheostomy, genetic variants, and additional surgery were primary measures. Fisher's exact test compared need for tracheostomy in patients with proposed high-risk (FGFR2 p.W290 or FGFR2 p.C342) versus low-risk genetic variants. RESULTS: Thirty patients with TCS were identified. Average age at diagnosis was 12 months (range 2-weeks to 7.9-years; standard deviation 19.8 months). Syndromes included Pfeiffer (37%), Apert (37%), and Crouzon (26%). Severe obstructive sleep apnea was present in 76% of patients. Tracheostomy was performed in 17 patients (57%); five were successfully decannulated. Additional interventions included adenotonsillectomy (57%), nasal (20%), laryngeal (17%), and craniofacial skeletal surgery (87%). All patients with Pfeiffer syndrome and FGFR2 p.W290C variants and 83% of patients with FGFR2 p.C342 variants required tracheostomy, differing from other variants (P = .02, odds ratio 33, 95% confidence interval 1.56-697.96). One patient (3%) died. CONCLUSION: TCS contributes to multilevel airway obstruction in patients with syndromic craniosynostosis. Genetic testing in patients with FGFR2-related syndromic craniosynostoses may identify those at risk of TCS and facilitate early intervention. A better understanding of this patient population may foster individualized airway management strategies and improve outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:215-221, 2022.

Prednisolone suppresses collagen-encoding gene expression causing cartilage defects in zebrafish larvae.

Glucocorticoid-induced osteoporosis (GIOP) is a clinically important disease. Despite many studies, the intrinsic pathogenesis of GIOP is still not fully understood. Cartilage is the target tissue of the glucocorticoid prednisolone (PN). To explore the intrinsic mechanism of PN-induced cartilage damage, we performed cartilage staining and cell transfection experiments in zebrafish larvae treated with PN. The results showed that PN caused cartilage damage in zebrafish at 25 µM. Moreover, after treatment with PN, it was found that collagen-encoding gene expression was significantly reduced. Further research revealed that the glucocorticoid receptor (GR) mediates the transcriptional inhibition of collagen genes by PN. These results indicate that glucocorticoids cause cartilage damage by inhibiting the expression of collagen genes through their receptors. Our study provides new insights into GIOP.

Cervical chondrocutaneous branchial remnants: A report of 29 cases and review of the literature.

OBJECTIVE: Cervical chondrocutaneous branchial remnants (CCBRs) are rare masses located in the anterior region of the neck. Though the basic characteristics of these rare masses were first described by Atlan in 1997, a critical amount of information about these masses remains unknown. This study aimed to further clarify the characteristics of these rare masses. METHODS: We retrospectively reviewed the clinical records of patients with CCBRs in our facility during a 32-year period ranging from 1988 to 2019. We then compared our clinical records with other case reports. RESULTS: There were 29 patients with CCBRs in our facility, including 19 males and ten females, Three patients were involved bilaterally (among patients involved unilaterally, the right side included 11 patients, and the left side was 15 patients), eight patients also had associated abnormalities. We submitted CCBRs from 18 patients to pathology, and all of them contained elastic cartilages. Among all the surgical data could be confirmed, cartilages did not reach beyond the musculature of the neck. We could confirm a similar tendency with Atlan regarding sex, the location of CCBRs (involvement side, localization in the neck), and the depth of CCBRs. Among the cases contained in this study, there was a disparity in the rate of associated abnormalities and pathology of contained cartilages. CONCLUSION: Some critical characteristics of CCBRs included, a male predominance, scarcity of bilateral cases and common left side involvement among unilateral involved cases, a common location of CCBRs in the inferior third of the neck and anterior to the sternocleidomastoid muscle, and an involvement of cartilage in CCBRs which has no connections to deep underlying structure of the neck. Further investigations are required to determine the origin of CCBRs and the precise incidence of the associated abnormalities. Systemic examination in patients with CCBRs is recommended because many associated abnormalities have been reported.

Bilateral cervical chondrocutaneous branchial remnants: A case report and a review of the literature.

RATIONALE: Cervical chondrocutaneous branchial remnants are rare, benign, congenital anomalies, frequently seen bilaterally. PATIENT CONCERNS: Here, we report the case of a 4-month-old female infant who presented with bilateral lower neck skin tag since birth. DIAGNOSIS AND INTERVENTIONS: The patient underwent mass excision. The final pathological diagnosis was bilateral cervical chondrocutaneous branchial remnants with hyaline cartilage. OUTCOMES: No complications were observed after excision. One-year follow-up revealed no recurrence. LESSONS: Bilateral chondrocutaneous branchial remnants are rare anomalies. They are often associated with cardiac or genitourinary abnormalities. Therefore, additional preoperative imaging of the abdomen and heart are recommended.

The anti-epileptic drug valproic acid causes malformations in the developing craniofacial skeleton of zebrafish larvae.

Valproic acid (VPA) is an anti-epileptic drug known to cause congenital craniofacial abnormalities, including orofacial clefts (OFC). The exact mechanisms by which VPA leads to craniofacial skeletal malformations are poorly understood. In this study, we investigated the effects of VPA on cartilage and bone formation in the zebrafish larval head during 1-13 hpf (early) and 25-37 hpf (late) development in which cranial neural crest cells (CNCCs) arise and then proliferate and differentiate, respectively. Double-staining for cartilage and bone at 5 dpf revealed that VPA reduced cartilage and bone formation in a dose-dependent manner after both early or late exposure. Several different CNCC-derived cartilage and bone elements were affected in both groups. In the early group (100 µM VPA), the posterior head length and the ethmoid plate were reduced in length (both p < 0.01), while mineralization of 4 out of 9 bone elements was often lacking (all p < 0.01). In the late group (100 µM VPA), also the posterior head length was reduced as well as the length of the ceratohyals (both p < 0.01). Similar to early exposure, mineralization of 3 out of 9 bone elements was often lacking (all p < 0.01). These results indicate that both CNCC formation (early) and differentiation (late) are hampered by VPA treatment, of which the consequences for bone and cartilage formation are persistent at 5 dpf. Indeed, we also found that the expression of several genes related to cartilage and bone was upregulated at 5 dpf. These data indicate a compensatory reaction to the lack of cartilage and bone. Altogether, VPA seems to induce craniofacial malformations via disturbed CNCC function leading to defects in cartilage and bone formation.

Maldevelopment of intrapulmonary bronchial cartilage in congenital diaphragmatic hernia.

BACKGROUND: Pulmonary hypoplasia is an important cause of morbidity and mortality in infants with congenital diaphragmatic hernia (CDH). This study aimed to verify our hypothesis that the abnormal development of bronchial cartilage as well as alveolar immaturity, might play a central role in hypoplasia of the lung in human CDH. METHOD: We retrospectively analyzed autopsied lungs from 10 CDH cases and compared with nine age-matched controls to assess the bronchial cartilage and alveolar maturity using morphological techniques. RESULT: Ki-67 and thyroid transcription factor-1 (TTF-1) expression in the alveoli significantly increased in bilateral lungs with CDH. The shortest distance from the bronchial cartilage to the pleura was significantly shorter in ipsilateral (left) lungs with CDH, showing a positive correlation with the radial alveolar count (RAC). Regarding the small bronchial cartilages less than 20 000 µm2 , the average cartilage area significantly decreased in left lungs with CDH, and tended to decrease in right lungs with CDH. In addition, cartilage around the bronchi less than 200 µm in diameter tended to be smaller in left lungs with CDH. In contrast, regarding the cartilage around the bronchi 200 to 400 µm in diameter, the ratio of the total cartilage area relative to the bronchial diameter tended to be higher in left lungs with CDH, although there was a large variation. CONCLUSIONS: These opposite directional cartilage abnormalities around the distal and more proximal bronchi support our hypothesis that abnormal development of bronchial cartilage might play an important role in the hypoplastic lung in CDH.

Nasal Chondrosarcoma of the Lower Lateral Cartilage.

Head and neck chondrosarcomas are incredibly rare with documented cases arising from skull base, maxilla, larynx, and nasal septum. We present the first reported case of chondrosarcoma arising from the lower lateral cartilage of the nose treated with surgical resection and primary reconstruction.

Dicer1 is required for pigment cell and craniofacial development in zebrafish.

The multidomain RNase III endoribonuclease DICER is required for the generation of most functional microRNAs (miRNAs). Loss of Dicer affects developmental processes at different levels. Here, we characterized the zebrafish Dicer1 mutant, dicer1sa9205, which has a single point mutation induced by N-ethyl-N-nitrosourea mutagenesis. Heterozygous dicer1sa9205 developed normally, being phenotypically indistinguishable from wild-type siblings. Homozygous dicer1sa9205 mutants display smaller eyes, abnormal craniofacial development and aberrant pigmentation. Reduced numbers of both iridophores and melanocytes were observed in the head and ventral trunk of dicer1sa9205 homozygotes; the effect on melanocytes was stronger and detectable earlier in development. The expression of microphthalmia-associated transcription factor a (mitfa), the master gene for melanocytes differentiation, was enhanced in dicer1-depleted fish. Similarly, the expression of SRY-box containing gene 10 (sox10), required for mitfa activation, was higher in mutants than in wild types. In silico and in vivo analyses of either sox10 or mitfa 3'UTRs revealed conserved potential miRNA binding sites likely involved in the post-transcriptional regulation of both genes. Based on these findings, we propose that dicer1 participates in the gene regulatory network governing zebrafish melanocyte differentiation by controlling the expression of mitfa and sox10.

Disarticulation-Associated Femoral Head Separation in Clinically Normal Broilers: Histologic Documentation of Underlying and Predisposing Cartilage Abnormalities.

Routine and quantitative histologic studies on femoral head separation (FHS) associated with coxofemoral joint disarticulation at necropsy were conducted on 125 femoral heads collected from 21- to 50-day-old clinically normal broilers. The study compared groups demonstrating grossly detached femoral heads (DFHs) with those having attached femoral heads (AFHs). Marked microscopic lesions compatible with osteochondrosis (OCD) consistently occurred along the separation surface in the DFH population. The histologic changes consisted of cartilage degeneration and necrosis sometimes forming small clefts or microfractures. Hemorrhage and less frequent inflammatory cells were often present along the separation surfaces. Small foci of OCD in the femur occurred in the AFH group with lesser frequency and severity. The histologic changes were mainly found within the proximal proliferative zone of the physis near the epiphyseal junction. Histomorphometry disclosed significant quantitative reductions in chondrocyte density with increased pyknosis occurring adjacent to the separation site and to a lesser extent in deeper regions of the growth plate for the DFH compared with AFH. Measurements made along the separation surface of the percentage length occupied by osteochondrotic defects and actual separated cartilage disclosed significant differences between evaluation groups. However, determinations of vascular canal areas present within two or more regions of the growth plate revealed a slight and significant increased area for DFH compared with AFH. Severity scores for the occurrence of microthrombi within the growth plate showed no difference between the groups. The pathogenesis of FHS in broilers is related to defective cartilage production or degeneration resulting in increased fragility. This contrasts with the proposed pathogenesis of OCD in mammals, which involves ischemic necrosis due to underlying vascular defects. The results for the FHS-disarticulation model also differ from those reported for glucorticoid-induced femoral head necrosis in broilers. The FHS-associated lesions occurred without histologic evidence of bacterial chondritis or osteomyelitis.

Separación de la cabeza femoral asociada a la desarticulación en pollos de engorde clínicamente normales: documentación histológica de anomalías del cartílago subyacentes y predisponentes. Estudios histológicos de rutina y cuantitativos sobre la separación de la cabeza femoral (FHS) asociados con la desarticulación de la articulación coxofemoral durante la necropsia se realizaron en 125 cabezas femorales recolectadas de pollos de engorde clínicamente normales de 21 a 50 días de edad. El estudio comparó los grupos que demostraron cabezas femorales separadas (DFH) con los que tenían cabezas femorales unidas (AFH). Lesiones microscópicas marcadas compatibles con osteocondrosis (OCD) ocurrieron consistentemente a lo largo de la superficie de separación en la población de aves con cabezas femorales separadas. Los cambios histológicos consistieron en degeneración del cartílago y necrosis, formando a veces pequeñas hendiduras o microfracturas. La hemorragia y la presencia menos frecuente de células inflamatorias estaban presentes a lo largo de las superficies de separación. Se produjeron con menor frecuencia y gravedad, focos pequeños de osteocondrosis en el fémur en el grupo de aves con cabezas femorales unidas. Los cambios histológicos se encontraron principalmente en la zona proliferativa proximal de la fisis cerca de la unión epifisaria. La histomorfometría reveló reducciones cuantitativas significativas en la densidad de condrocitos con un aumento de la picnosis que ocurrió adyacente al sitio de separación y en menor medida en regiones más profundas de la placa de crecimiento en las aves con cabezas femorales separadas en comparación con las aves con cabezas femorales unidas. Las mediciones realizadas a lo largo de la superficie de separación del porcentaje de longitud ocupada por defectos osteocondróticos y con cartílago separado revelaron diferencias significativas entre los grupos de evaluación. Sin embargo, las determinaciones de las áreas del canal vascular presentes dentro de dos o más regiones de la placa de crecimiento revelaron un aumento leve y significativo del área para las aves con cabezas femorales separadas en comparación con las aves con cabezas femorales unidas. Las puntuaciones de severidad para la aparición de microtrombos dentro de la placa de crecimiento no mostraron diferencias entre los grupos. La patogenia de la separación de la cabeza femoral en pollos de engorde se relaciona con la producción o degeneración de cartílago defectuoso que resulta en un aumento de la fragilidad. Esto contrasta con la patogénesis propuesta para la osteocondrosis en mamíferos, que involucra necrosis isquémica debido a defectos vasculares subyacentes. Los resultados para el modelo de desarticulación-separación de la cabeza femoral también difieren de los reportados para la necrosis de la cabeza femoral inducida por glucorticoides en pollos de engorde. Las lesiones asociadas con la separación de la cabeza femoral ocurrieron sin evidencia histológica de condritis bacteriana u osteomielitis.

Signaling Events Downstream of AHR Activation That Contribute to Toxic Responses: The Functional Role of an AHR-Dependent Long Noncoding RNA (slincR) Using the Zebrafish Model.

BACKGROUND: A structurally diverse group of chemicals, including dioxins [e.g., 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)] and polycyclic aromatic hydrocarbons (PAHs), can xenobiotically activate the aryl hydrocarbon receptor (AHR) and contribute to adverse health effects in humans and wildlife. In the zebrafish model, repression of sox9b has a causal role in several AHR-mediated toxic responses, including craniofacial cartilage malformations; however, the mechanism of sox9b repression remains unknown. We previously identified a long noncoding RNA, sox9b long intergenic noncoding RNA (slincR), which is increased (in an AHR-dependent manner) by multiple AHR ligands and is required for the AHR-activated repression of sox9b. OBJECTIVE: Using the zebrafish model, we aimed to enhance our understanding of the signaling events downstream of AHR activation that contribute to toxic responses by identifying: a) whether slincR is enriched on the sox9b locus, b) slincR's functional contributions to TCDD-induced toxicity, c) PAHs that increase slincR expression, and d) mammalian orthologs of slincR. METHODS: We used capture hybridization analysis of RNA targets (CHART), qRT-PCR, RNA sequencing, morphometric analysis of cartilage structures, and hemorrhaging screens. RESULTS: The slincR transcript was enriched at the 5' untranslated region (UTR) of the sox9b locus. Transcriptome profiling and human ortholog analyses identified processes related to skeletal and cartilage development unique to TCDD-exposed controls, and angiogenesis and vasculature development unique to TCDD-exposed zebrafish that were injected with a splice-blocking morpholino targeting slincR. In comparison to TCDD exposed control morphants, slincR morphants exposed to TCDD resulted in abnormal cartilage structures and a smaller percentage of animals displaying the hemorrhaging phenotype. In addition, slincR expression was significantly increased in six out of the sixteen PAHs we screened. CONCLUSION: Our study establishes that in zebrafish, slincR is recruited to the sox9b 5' UTR to repress transcription, can regulate cartilage development, has a causal role in the TCDD-induced hemorrhaging phenotype, and is up-regulated by multiple environmentally relevant PAHs. These findings have important implications for understanding the ligand-specific mechanisms of AHR-mediated toxicity. https://doi.org/10.1289/EHP3281.

Are Patellofemoral Joint Alignment and Shape Associated With Structural Magnetic Resonance Imaging Abnormalities and Symptoms Among People With Patellofemoral Pain?

BACKGROUND: Patellofemoral malalignment has been observed among people with patellofemoral pain (PFP) and may be associated with the presence of imaging features of osteoarthritis, symptoms, and function. PURPOSE: To determine whether patellofemoral joint alignment and bony shape are associated with (1) cartilage, bone, and soft tissue morphological abnormalities defined on magnetic resonance imaging (MRI) and (2) reported symptoms and function among people with PFP. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Participants (mean ± SD age, 30.2 ± 9.5 years; range, 14-50 years; 78 females, 58.6%) completed questionnaires regarding demographics, pain, symptoms, and function and underwent a 3-T MRI scan of their more symptomatic eligible knee. Structural MRI abnormalities were scored with the MOAKS (Magnetic Resonance Imaging Osteoarthritis Knee Score), and MRI alignment and shape were measured with standardized methods. Associations among MOAKS features, PFP symptoms, and alignment and shape measures were evaluated with regression analyses (α = .05). RESULTS: Minor cartilage defects were present in 22 (16.5%) participants, patellar osteophytes in 83 (62.4%), anterior femur osteophytes in 29 (21.8%), Hoffa synovitis in 81 (60.9%), and prefemoral fat pad synovitis in 49 (36.8%). A larger Insall-Salvati ratio was significantly associated with the presence of patellar osteophytes (odds ratio [OR], 51.82; 95% CI, 4.20-640.01), Hoffa synovitis (OR, 60.37; 95% CI, 4.66-782.61), and prefemoral fat pad synovitis (OR, 43.31; 95% CI, 4.28-438.72) in the patellofemoral joint. A larger patellar tilt angle was significantly associated with the presence of minor cartilage defects (OR, 1.10; 95% CI, 1.00-1.20), the presence of patellar osteophytes (OR 1.12; 95%CI 1.02-1.22), and prefemoral fat pad synovitis (OR, 1.11; 95% CI, 1.03-1.20) in the patellofemoral joint. Finally, a larger bisect offset was significantly associated with the presence of minor cartilage defects (OR, 1.05; 95% CI, 1.00-1.11) and patellar osteophytes (OR, 1.07; 95% CI, 1.01-1.14) in the patellofemoral joint. The majority of patellofemoral alignment measures were not associated with symptoms or function. CONCLUSION: For people with PFP, the presence of morphological abnormalities defined on MRI appears to be related to particular patellofemoral alignment measures, including higher Insall-Salvati ratio (indicating patella alta), larger patellar tilt angle (indicating greater lateral tilt), and larger bisect offset (indicating greater lateral displacement). Hardly any associations were found with symptoms or function. So there might be a distinct subgroup of PFP that is more prone to developing patellofemoral osteoarthritis later in life, as particular alignment measures seem to be associated with the presence of patellar osteophytes. Prospective studies are required to investigate the longitudinal relationship between alignment or bony shape and morphological abnormalities defined on MRI in this patient population.

Maternal Bisphenol A exposure impaired endochondral ossification in craniofacial cartilage of rare minnow (Gobiocypris rarus) offspring.

Bisphenol A (BPA), an endocrine disrupting compound, is present in the aquatic environment. BPA can mimic estrogen and cause adverse effects on development and reproduction in different organisms. As epigenetic modifications due to BPA exposure have been reported, the interest on the effects of this chemical has increased. To assess the potential effects of maternal BPA exposure on offspring bone development, adult Gobiocypris rarus (G. rarus) females were exposed to 15 µg L-1 and 225 µg L-1 BPA for 21 days. Eggs were collected after artificial spawning and fertilized with the fresh milt of non-exposed male fish. The offspring were raised in clean water and randomly selected for examination at different development stages. Our results showed that specific effects including poor quality of the embryos, increased malformation (bent spine and tail), and delayed craniofacial cartilage ossification of the larvae. Additionally, the transcripts of ossification related genes were significantly downregulated in offspring, and the lysyloxidase activity decreased. The present study demonstrated the maternal-mediated skeleton toxicity of BPA and its adverse effects on G. rarus.

Effects of calcium and estrogen on the development of the ceratohyal cartilage in zebrafish (Danio rerio) larvae upon embryo and maternal cadmium exposure.

The present study is to investigate the reason why the ceratohyal cartilage (CH) angle of zebrafish larvae were larger compared to the control group after their female parents were treated with cadmium (F-Cd). However, the CH angle was smaller compared to the control group when embryos were directly exposed to Cd2+ for 72 h (D-Cd). Results showed that calcium contents of larvae were lower than the control, but the transporter isoforms trpv4 and trpv6 mRNA expressions were significantly increased upon D-Cd treatment. Furthermore, external Ca2+ added during D-Cd treatment reveals that the CH angles of larvae did not appear significantly different compared to the control. On the other hand, E2 (17ß-estradiol) contents were higher around 1.9 folds in the ovaries of females; CH angle were over 25°, and Cd2+ contents were higher around 6 folds than the control group on larvae treated through F-Cd treatment; CH angles and E2 levels on larvae were higher than the control after the larvae were treated with 1.84 µM E2 (D-E2); Estradiol receptor (ER) isoforms ERß1 and ERα mRNA expressions significantly increased when 0 hpf embryos were either treated with D-E2 or D-Cd. According to the results, we suggested that the CH angle of larvae become larger upon F-Cd treatment due to maternal Cd2+ inducing E2 levels. However, the CH angle of larvae appeared to be smaller compared to the control upon D-Cd treatment. We suggested that the CH angle decreased due to the decrease of Ca2+ contents upon Cd2+ exposure.

MS-222 short exposure induces developmental and behavioural alterations in zebrafish embryos.

MS-222 has been widely used as an anaesthetic in fish, thus, raising the need to infer about its toxicological safety during development. In this study, MS-222 toxicity in zebrafish embryos was evaluated after a 20-min exposure at different stages of development. Embryos exposed during the 256-cell stage displayed an increase in mortality, associated with defective early developmental pathways. Following exposure during the 50% epiboly stage, an increase in mortality and abnormal cartilage development, as well as changes in noggin expression were observed. Locomotor deficits were detected and associated with changes in early signalling pathways through the involvement of noggin. When exposed at the 1-4 somites stage, zebrafish were phenotypically normal, although presenting changes in the expression pattern of developmental genes. These findings indicate a teratogenic impact, independent of sodium channels that should be taken into consideration when MS-222 toxicity is discussed.

Endplate Defect Is Heritable, Associated With Low Back Pain and Triggers Intervertebral Disc Degeneration: A Longitudinal Study From TwinsUK.

STUDY DESIGN: Longitudinal study of spine magnetic resonance imaging (MRI) in a large-scale population-based study. OBJECTIVE: To determine the order of appearance of degenerative change in vertebral bodies and intervertebral discs. We also sought to define the influence of endplate defect on low back pain (LBP) and to determine whether there is a genetic influence on endplate defect. SUMMARY OF BACKGROUND DATA: Endplate defect is a magnetic resonance imaging trait, found to be associated with intervertebral disc degeneration. There is a lack of understanding regarding the mechanism underlying lumbar disc degeneration (LDD). Recent attention has shifted to vertebral endplate defects and their role in spine degeneration pathology. METHODS: Individuals from the TwinsUK spine study having longitudinal T2-weighted lumbar MR scans at baseline (n = 996) and a decade later (n = 438) were included. LDD, vertebral endplate defect by calculating a total endplate score, and Modic change (MC) were assessed using standard techniques. Mixed-effects models were used to determine the association between the features of spine pathology, adjusted for covariates. Endplate defect heritability was estimated using variance component analysis. RESULTS: Significant association was found between endplate defect, LDD, MRI features of LDD and MC was observed. Endplate defect was associated with severe disabling LBP (P ≤ 0.013) in multivariate analysis. An association between disc degeneration (DD) at baseline and MC at follow-up was shown at upper lumbar levels. Total endplate score was heritable with estimated additive genetic component A = 55.3% (95% CI 43.0-65.4). CONCLUSION: Endplate defect, LDD, and MC are all independent risk factors for episodes of severe and disabling LBP. Longitudinal analysis showed DD is followed by MC. Endplate defect has significant heritability of 55%. However, whether endplate defect triggers DD or these pathological changes occur concurrently could not be conclusively determined. LEVEL OF EVIDENCE: 2.

Increased FGF8 signaling promotes chondrogenic rather than osteogenic development in the embryonic skull.

The bones of the cranial vault are formed directly from mesenchymal cells through intramembranous ossification rather than via a cartilage intermediate. Formation and growth of the skull bones involves the interaction of multiple cell-cell signaling pathways, with fibroblast growth factors (FGFs) and their receptors exerting a prominent influence. Mutations within the FGF signaling pathway are the most frequent cause of craniosynostosis, which is a common human craniofacial developmental abnormality characterized by the premature fusion of the cranial sutures. Here, we have developed new mouse models to investigate how different levels of increased FGF signaling can affect the formation of the calvarial bones and associated sutures. Whereas moderate Fgf8 overexpression resulted in delayed ossification followed by craniosynostosis of the coronal suture, higher Fgf8 levels promoted a loss of ossification and favored cartilage over bone formation across the skull. By contrast, endochondral bones were still able to form and ossify in the presence of increased levels of Fgf8, although the growth and mineralization of these bones were affected to varying extents. Expression analysis demonstrated that abnormal skull chondrogenesis was accompanied by changes in the genes required for Wnt signaling. Moreover, further analysis indicated that the pathology was associated with decreased Wnt signaling, as the reduction in ossification could be partially rescued by halving Axin2 gene dosage. Taken together, these findings indicate that mesenchymal cells of the skull are not fated to form bone, but can be forced into a chondrogenic fate through the manipulation of FGF8 signaling. These results have implications for evolution of the different methods of ossification as well as for therapeutic intervention in craniosynostosis.

Diffuse large B-cell lymphoma chemotherapy reveals a combined immunodeficiency syndrome in cartilage hair hypoplasia.

Cartilage hair hypoplasia (CHH) is a rare autosomal recessive ribosomopathy characterised by skeletal and integumentary system manifestations. It may also present with varied forms and intensities of haematopoietic and/or immune disorders. We report a 27-year-old female who presented a picture of combined immunodeficiency after receiving an adriamycin-based chemotherapy regimen followed by autologous stem cell transplantation. Her medical history indicated neonatal dwarfism, recurrent ear, nose and throat and respiratory infections, and hypogammaglobulinaemia, which were suggestive of a primary minor B-cell immune deficiency. Taken together, the diagnosis of cartilage hair hypoplasia was suspected and confirmed by means of molecular biological analysis. Here, we discuss the causal relationship and molecular mechanisms existing between both primary immunodeficiency and lymphoma conditions and between chemotherapy cytotoxicity and aggravation of the immune system and associated hematopoietic dysfunction, considering the role of all these components in light of the initially undiagnosed cartilage hair hypoplasia. Finally, this case highlights the importance of screening for primary immunodeficiencies in the setting of a diagnosis of lymphoma and/or dwarfism; moreover, CHH must be distinguished from other causes of small size; its diagnosis and complete check-up must include the molecular characterisation, and its management must be global in collaboration with haematologists, immunologists and internists.