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BACKGROUND: Constitutive activation of the PI3K-AKT-mTOR pathway (mTOR pathway) underlies megalencephaly in many patients. Yet, prevalence of the involvement of the PI3K-AKT-mTOR pathway in patients with megalencephaly remains to be elucidated, and molecular diagnosis is challenging. Here, we have successfully established a combination of genetic and biochemical methods for diagnosis of mTOR pathway-associated megalencephaly, and have attempted to delineate the clinical characteristics of the disorder. METHODS: Thirteen patients with an increased head circumference and neurological symptoms participated in the study. To evaluate the activation of the mTOR pathway, we performed western blot analysis to determine the expression levels of phosphorylated S6 ribosomal protein (phospho-S6 protein) in lymphoblastoid cell lines from 12 patients. Multiplex targeted sequencing analysis for 15 genes involved in the mTOR pathway was performed on 12 patients, and whole-exome sequencing was performed on one additional patient. Clinical features and MRI findings were also investigated. RESULTS: We identified pathogenic mutations in six (AKT3, 1 patient; PIK3R2, 2 patients; PTEN, 3 patients) of the 13 patients. Increased expression of phospho-S6 protein was demonstrated in all five mutation-positive patients in whom western blotting was performed, as well as in three mutation-negative patients. Developmental delay, dysmorphic facial features were observed in almost all patients. Syndactyly/polydactyly and capillary malformations were not observed, even in patients with AKT3 or PIK3R2 mutations. There were no common phenotypes or MRI findings among these patients. CONCLUSIONS: A combination of genetic and biochemical methods successfully identified mTOR pathway involvement in nine of 13 (approximately 70%) patients with megalencephaly, indicating a major contribution of the pathway to the pathogenesis of megalencephaly. Our combined approach could be useful to identify patients who are suitable for future clinical trials using an mTOR inhibitor.
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Megalencefalia/diagnóstico , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Quinasas S6 Ribosómicas/metabolismo , Adolescente , Línea Celular , Niño , Preescolar , Femenino , Humanos , Masculino , Megalencefalia/genética , Megalencefalia/metabolismo , Mutación , Fosfohidrolasa PTEN/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Análisis de Secuencia de ADN/métodos , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
AIM: We evaluated combined genetic analyses with targeted next-generation sequencing (NGS), multiplex ligation probe amplification (MLPA) of Jagged1 (JAG1) genes and microarray comparative genomic hybridisation (CGH) in subjects with Alagille syndrome, incomplete clinical features of Alagille syndrome and biliary atresia. METHODS: Subjects recruited from April 2013 to December 2015 underwent a targeted NGS analysis, including JAG1 and Notch homolog 2 (NOTCH2). If no mutations were detected in JAG1 or NOTCH2, or if copy number variations were suggested by the NGS analysis, we performed an MLPA analysis of JAG1. We also performed a microarray CGH analysis with whole-exon deletion detected by the MLPA analysis. RESULTS: We analysed 30 subjects with Alagille syndrome, nine with incomplete Alagille syndrome and 17 with biliary atresia and detected pathogenic mutations in JAG1 or NOTCH2 in 24/30 subjects with Alagille syndrome and in 4/9 subjects with incomplete Alagille syndrome. No pathogenic mutations were detected in subjects with biliary atresia. The frequency of JAG1 mutations was as follows: single nucleotide variants (51.9%), small insertion or deletion (29.6%) and gross deletion (18.5%). CONCLUSION: Combined genetic analyses achieved efficient diagnostic yields for subjects with Alagille syndrome and incomplete Alagille syndrome.
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Síndrome de Alagille/diagnóstico , Pruebas Genéticas , Proteína Jagged-1/genética , Síndrome de Alagille/genética , Atresia Biliar/genética , Hibridación Genómica Comparativa , Femenino , Humanos , Masculino , Reacción en Cadena de la Polimerasa MultiplexRESUMEN
OBJECTIVES: To ascertain a molecular genetic diagnosis for subjects with neonatal/infantile intrahepatic cholestasis (NIIC) by the use of next-generation sequencing (NGS) and to perform a genotype-phenotype correlation. STUDY DESIGN: We recruited Japanese subjects with NIIC who had no definitive molecular genetic diagnosis. We developed a diagnostic custom panel of 18 genes, and the amplicon library was sequenced via NGS. We then compared clinical data between the molecular genetically confirmed subjects with NIIC. RESULTS: We analyzed 109 patients with NIIC ("genetic cholestasis," 31 subjects; "unknown with complications" such as prematurity, 46 subjects; "unknown without complications," 32 subjects), and a molecular genetic diagnosis was made for 28 subjects (26%). The rate of positive molecular genetic diagnosis in each category was 22 of 31 (71%) for the "genetic cholestasis" group, 2 of 46 (4.3%) for the "unknown with complications" group, and 4 of 32 (12.5%) for the "unknown without complications" group. The grouping of the molecular diagnoses in the group with genetic cholestasis was as follows: 12 with Alagille syndrome, 5 with neonatal Dubin-Johnson syndrome, 5 with neonatal intrahepatic cholestasis caused by citrin deficiency, and 6 with progressive familial intrahepatic cholestasis or benign recurrent intrahepatic cholestasis with low gamma-glutamyl transpeptidase levels. Several clinical datasets, including age of onset, direct bilirubin, and aminotransferases, were significantly different between the disorders confirmed using molecular genetic diagnosis. CONCLUSION: Targeted NGS can be used for molecular genetic diagnosis in subjects with NIIC. Clinical diagnosis should be accordingly redefined in the view of molecular genetic findings.
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Colestasis Intrahepática/diagnóstico , Colestasis Intrahepática/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , Bilirrubina/sangre , Proteínas de Unión al Calcio/deficiencia , Aberraciones Cromosómicas , Exones , Femenino , Eliminación de Gen , Estudios de Asociación Genética , Genómica , Humanos , Lactante , Recién Nacido , Japón , Ictericia Idiopática Crónica/diagnóstico , Ictericia Idiopática Crónica/genética , Masculino , Biología Molecular , Transportadores de Anión Orgánico/deficiencia , gamma-Glutamiltransferasa/genéticaRESUMEN
The clinical outcomes in patients with ovarian cancer have been significantly improved by Poly(adenosine diphosphate-ribose) polymerase inhibitors (PARP-is). However, the best therapeutic strategy for recurrence during PARP-i maintenance therapy remains unknown. Herein, we elucidated the efficacy of platinum-based chemotherapy after PARP-i treatment in recurrent ovarian cancer. Eligible patients had experienced relapses during PARP-i maintenance therapy lasting at least 6 months and had received subsequent platinum-based chemotherapy at our institution between January 2019 and March 2024. Progression-free survival (PFS), overall survival (OS), and risk factors for PFS were evaluated. Sixty-six patients were assessed for eligibility and eighteen were enrolled. The median follow-up period was 14.5 months. The PFS and OS of all patients were 6.5 and 17.6 months, respectively. The evaluation of the risk factors for PFS revealed that age, pathological type, duration of PARP-i maintenance therapy, prior lines of chemotherapy, and PARP-i dose reduction were not significant prognostic markers. However, bevacizumab use in subsequent therapies significantly extended the PFS. The median PFS was 3.1 months in the chemotherapy-alone group and 8.9 months in the chemotherapy with bevacizumab group (log-rank p = 0.022). Platinum-based chemotherapy with bevacizumab in subsequent therapies would provide substantial benefits in the PFS of patients with recurrent ovarian cancer.
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Diagnostic laparoscopy is useful in the management of gynecological cancers; however, it can occasionally result in the detection of other malignancies. Occult breast cancer (OBC) is metastatic breast cancer without a recognized primary breast lesion. We report a rare case of OBC that was detected laparoscopically. A 64-year-old female presented to our hospital with back pain. Magnetic resonance imaging (MRI) revealed a 50 mm multicystic tumor with an internal nodule in the right ovary. Positron emission tomography/computed tomography showed abnormal accumulation in multiple lymph nodes, moderate accumulation in the ovarian tumor nodule, and no accumulation in the breasts. Ovarian cancer was suspected, and a diagnostic laparoscopy was performed. Laparoscopically, a cystic tumor in the right ovary and 10 mm nodule in the right round ligament were observed and partially resected. Immunohistopathologically, the nodules of the round ligament exhibited features consistent with those of breast cancer, but the ovarian tumor was a seromucinous borderline tumor. MRI revealed no breast lesions. Therefore, the malignancy was diagnosed as an OBC.
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CONTEXT: Thyroglobulin (Tg), encoded by TG, is essential for thyroid hormone synthesis. TG defects result in congenital hypothyroidism (CH). Most reported patients were born before the introduction of newborn screening (NBS). OBJECTIVE: We aimed to clarify the phenotypic features of patients with TG defects diagnosed and treated since the neonatal period. METHODS: We screened 1061 patients with CH for 13 CH-related genes and identified 30 patients with TG defects. One patient was diagnosed due to hypothyroidism-related symptoms and the rest were diagnosed via NBS. Patients were divided into 2 groups according to their genotypes, and clinical characteristics were compared. We evaluated the functionality of the 7 missense variants using HEK293 cells. RESULTS: Twenty-seven rare TG variants were detected, including 15 nonsense, 3 frameshift, 2 splice-site, and 7 missense variants. Patients were divided into 2 groups: 13 patients with biallelic truncating variants and 17 patients with monoallelic/biallelic missense variants. Patients with missense variants were more likely to develop thyroid enlargement with thyrotropin stimulation than patients with biallelic truncating variants. Patients with biallelic truncating variants invariably required full hormone replacement, whereas patients with missense variants required variable doses of levothyroxine. Loss of function of the 7 missense variants was confirmed in vitro. CONCLUSION: To our knowledge, this is the largest investigation on the clinical presentation of TG defects diagnosed in the neonatal period. Patients with missense variants showed relatively mild hypothyroidism with compensative goiter. Patients with only truncating variants showed minimal or no compensative goiter and required full hormone replacement.
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Hipotiroidismo Congénito , Estudios de Asociación Genética , Tamizaje Neonatal , Tiroglobulina , Humanos , Hipotiroidismo Congénito/genética , Hipotiroidismo Congénito/diagnóstico , Femenino , Masculino , Tiroglobulina/genética , Recién Nacido , Japón/epidemiología , Preescolar , Mutación Missense , Lactante , Niño , Fenotipo , Genotipo , Células HEK293 , Pueblos del Este de AsiaRESUMEN
While cancer cure is the primary goal, fertility preservation is also a cornerstone of the underlying principle of treatment for ovarian germ cell tumors. Growing teratoma syndrome (GTS) presents with growth of mature teratomas during or after chemotherapy. We report a case of successful treatment of GTS in the anterior abdominal wall involving reconstruction. A 23-year-old woman with a suspected right ovarian mature teratoma with torsion underwent emergency laparoscopically assisted extracorporeal ovarian cystectomy. Histopathological findings revealed a grade 1 immature teratoma. After two months, postoperative α-fetoprotein (AFP) levels increased, and disseminated lesions developed not only in the pelvic cavity but also in the abdominal wound where the tumor had been extracted using an extracorporeal technique at the time of primary surgery. The patient underwent laparoscopic right salpingo-oophorectomy, excision of multiple peritoneal nodules, and biopsy of abdominal wall mass. The left rectus abdominis muscle tumor could not be removed. All of these nodules were diagnosed as metastatic immature teratomas. Although the patient received three cycles of chemotherapy, the residual tumor in the abdominal wall grew remarkably despite post-chemotherapy normalization of AFP levels. Both rectus abdominis muscles involving the residual tumors were removed and reconstructed using a left tensor fascia lata muscle flap. Histopathologically, the residual tumors were identified as mature teratomas with no immature elements, resulting in GTS. The patient got pregnant without the need of fertility treatment and gave birth uneventfully by cesarean section. Thus, reconstruction with a tensor fascia lata muscle flap facilitated complete removal of GTS while preserving fertility.
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Sitosterolemia (OMIM #210250) is a rare lipid disorder caused by variants in genes encoding adenosine triphosphate (ATP)-binding cassette subfamily G Member 5 (ABCG5) or 8 (ABCG8), which play roles in the intestinal and biliary excretion of cholesterol and plant sterols, such as sitosterol and campesterol. Although considered an autosomal recessive disorder, recent reports have shown that a heterozygous ABCG5 variant can also cause mild symptoms. Here, we report the case of an infant with a heterozygous variant of ABCG5. A 6-mo-old breast-fed Japanese male infant was found to have elevated serum total cholesterol and low-density lipoprotein-cholesterol (LDL-C) levels of 528 mg/dL and 449 mg/dL, respectively, upon examination for growth disturbances. As weaning progressed, the cholesterol levels normalized. Genetic analysis revealed that the patient and his mother had the heterozygous variant c.1166G>A (p.Arg389His) in ABCG5. Compared to his father, who did not have the ABCG5 variant, the patient and his mother had mild elevations of serum sitosterol and campesterol. Serum sitosterol and campesterol levels were 9.6 and 12 µg/mL for the patient, 4.9 and 9.3 µg/mL for his mother, and 2.1 and 3.4 µg/mL for his father, respectively. Therefore, heterozygous variants of ABCG5 may lead to transient hypercholesterolemia during breastfeeding.
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Background: Hematocolpos due to imperforate hymen is an important differential diagnosis of abdominal pain in early adolescent stage. However, hematocolpos due to lower vaginal agenesis must be considered because the management differs. Case Presentation: A healthy 11-year-old girl presented with a 2-day left lower abdominal pain history. Her breast development had begun, but she had not reached menarche. Computed tomography showed high absorptive value liquid filling the upper vaginal to uterine cavity, a pale highly absorptive fluid component suggestive of hemorrhagic ascites in the abdominal cavity on both sides of the uterus, and normal bilateral ovaries. Magnetic resonance imaging diagnosed hematocolpos due to lower vaginal agenesis. The blood clot was aspirated with a transabdominal ultrasound-guided transvaginal puncture. Conclusion: History-taking, imaging tests, and appropriate collaboration with obstetrician/gynecologist with awareness of secondary sexual characteristics were crucial in this case.
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Later-borns tend to be shorter than first-borns in childhood and adulthood. However, large-scale prospective studies examining growth during infancy according to birth order are limited. We aimed to investigate the relationship between birth order and growth during the first 4 years of life in a Japanese prospective birth cohort study. A total of 26,249 full-term singleton births were targeted. General linear and multivariable logistic regression models were performed and adjusted for birth weight, parents' heights, maternal age at delivery, gestational weight gain, maternal smoking and alcohol drinking status during pregnancy, household income, breastfeeding status, and Study Areas. The multivariate adjusted mean length Z-scores in "first-borns having no sibling", "first-borns having siblings", "second-borns", and "third-borns or more" were -0.026, -0.013, 0.136, and 0.120 at birth and -0.324, -0.330, -0.466, and -0.569 at 10 months, respectively. Results similar to those at 10 months were observed at 1.5, 3, and 4 years. The adjusted odds ratios (95% confidence intervals) of short stature at 4 years in "first-borns having siblings", "second-borns", and "third-borns or more" were 1.08 (0.84-1.39), 1.36 (1.13-1.62), and 1.50 (1.20-1.88), respectively, versus "first-borns having no sibling". Birth order was significantly associated with postnatal growth and may be a factor predisposing to short stature in early childhood.
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Desensitization protocols of platinum-based agents are recommended for patients with a history of hypersensitivity reaction (HSR). Herein, we report the first case of a successful desensitization therapy with nedaplatin after HSR to carboplatin and nedaplatin for platinum-sensitive recurrent ovarian cancer. A 53 year-old woman was diagnosed with stage IIIC serous carcinoma of the ovary and underwent primary debulking surgery followed by an adjuvant chemotherapy. The tumor relapsed 4 times in 10 years after the initial treatment, and platinum-based chemotherapy was performed on each occasion. HSR to carboplatin without and with desensitization protocol occurred during the 9th cycle of treatment and 2nd cycle of retreatment, respectively. Additionally, HSR to nedaplatin occurred during the 16th cycle of nedaplatin treatment. A four-step desensitization protocol with nedaplatin was conducted without occurrence of any severe adverse event. Nedaplatin desensitization regimen could be a new alternation for HSR to platinum-based agents.
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X-linked nephrogenic diabetes insipidus (NDI) is caused by variations in arginine vasopressin receptor 2 (AVPR2). Some patients show partial resistance to arginine vasopressin (AVP). A 19-month-old Japanese boy presented with polydipsia since infancy. His mother had a history of polydipsia during pregnancy, and his maternal granduncle also had polydipsia. Intermediate urine osmolality and markedly high plasma AVP levels were observed in the water deprivation test. Subsequent pitressin administration caused no further elevation in urine osmolality. We diagnosed the patient with partial NDI, initiated therapy with hydrochlorothiazide, and placed him on a low-sodium diet. Although his urine volume decreased by 20-30% after the initiation of therapy, progressive hydronephrosis and growth retardation developed 2 years later. We investigated his genetic background by multiplex targeted sequencing of genes associated with inherited renal diseases, including AVPR2 and aquaporin-2 (AQP2). We identified a hemizygous missense variant in AVPR2 NM_000054:c.371A>G,p.(Tyr124Cys) in the boy and a heterozygous variant in the mother at the same locus. Distinguishing partial NDI from primary polydipsia is difficult because of its mild symptoms. Markedly elevated plasma AVP levels with intermediate urine osmolality may suggest partial NDI, and genetic analysis can be useful for such patients.
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Progesterone is used to treat uterine endometrial cancer in young patients wishing to preserve their fertility as well as in advanced or recurrent patients, but its response rate is limited. The antitumor effect of progesterone is mediated by progesterone receptor (PR) binding. Hence, loss of progesterone's therapeutic effect, i.e., development of progesterone resistance, is mainly due to decreased PR expression. However, little is known about underlying mechanisms that regulate PR expression. Immunohistochemistry analysis of specimens from 31 young, endometrial cancer patients showed that elevated PR expression significantly increased (P < 0.05) rates of progression-free and overall survival. We investigated mechanisms of regulating PR expression and suppressing cell proliferation using genistein, a chemotherapeutic agent against different cancers. Genistein inhibits cell growth by inducing cell cycle arrest in G2 and apoptosis; moreover, it upregulates prolonged expression of PR-B and forkhead box protein O1, regardless of estrogen receptor alpha expression in endometrial cancer cells. Genistein-induced PR expression decreases CCAAT/enhancer binding protein beta expression and activates c-Jun N-terminal kinase pathway, rather than causing epigenetic alterations of the PR promoter. Therefore, increased PR expression is an important antitumor effect of genistein. This may help to improve the response rates of fertility-sparing treatments for young patients.
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Neoplasias Endometriales , Receptores de Progesterona , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/genética , Neoplasias Endometriales/metabolismo , Femenino , Genisteína/farmacología , Genisteína/uso terapéutico , Humanos , Progesterona/farmacología , Pronóstico , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismoRESUMEN
Retroperitoneal liposarcoma is a rare tumor, and its dedifferentiated subtype and a larger diameter are associated with a poor prognosis. However, there are few reports of retroperitoneal liposarcomas, both with a dedifferentiated subtype and a diameter of >30 cm. We report a case of a giant retroperitoneal liposarcoma with a dedifferentiated subtype. A 78-year-old woman presented to our hospital with abdominal distension and loss of appetite. Computed tomography and magnetic resonance imaging findings revealed a 35-cm-diameter solid tumor in the peritoneal cavity. CA125 (64.8 U/mL) and HE4 (229.0 pmol/L) were elevated preoperatively raising suspicion for ovarian malignancy. However, intraoperative findings revealed that the tumor originated in the retroperitoneal cavity. Reductive surgery for the tumor and partial resection of the sigmoid colon and left ureter were performed, and pathological examination confirmed a retroperitoneal dedifferentiated liposarcoma. Although her symptoms improved postoperatively, she died 11 months after surgery due to disease progression.
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SLC26A4 is a known iodide transporter, and is localized at the apical membrane of thyrocytes. Previously, we reported that SLC26A7 is also involved in iodide transport and that Slc26a7 is a novel causative gene for congenital hypothyroidism. However, its detailed role in vivo remains to be elucidated. We generated mice that were deficient in Slc26a7 and Slc26a4 to delineate differences and associations in their roles in iodide transport. Slc26a7-/- mice showed goitrous congenital hypothyroidism and mild growth failure on a normal diet. Slc26a7-/- mice with a low iodine environment showed marked growth failure. In contrast, Slc26a4-/- mice showed no growth failure and hypothyroidism in the same low iodine environment. Double-deficient mice showed more severe growth failure than Slc26a7-/- mice. RNA-seq analysis revealed that the number of differentially expressed genes (DEGs) in Slc26a7-/- mice was significantly higher than that in Slc26a4-/- mice. These indicate that SLC26A7 is more strongly involved in iodide transport and the maintenance of thyroid function than SLC26A4.
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Antiportadores de Cloruro-Bicarbonato/metabolismo , Hipotiroidismo Congénito , Yodo , Transportadores de Sulfato/metabolismo , Animales , Antiportadores de Cloruro-Bicarbonato/genética , Hipotiroidismo Congénito/genética , Yoduros , Yodo/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Ratones , Transportadores de Sulfato/genéticaRESUMEN
This study aimed to evaluate the efficacy and safety of computed tomography-magnetic resonance imaging (CT-MRI)-guided multi-catheter interstitial brachytherapy for patients with bulky (≥4 cm) and high-risk, stage IIB-IVB advanced cervical cancer. Eighteen patients who underwent concurrent chemoradiotherapy with multi-catheter interstitial brachytherapy between September 2014 and August 2020 were enrolled. The prescribed dose of external beam radiotherapy was 45-50.4 Gy, and the brachytherapy high-dose-rate aim was 25-30 Gy per 5 fractions. The endpoints were four-year local and pelvic control rates, four-year disease-free and overall survival rates, and the adverse events rate. The median follow-up period was 48.4 months (9.1-87.5 months). Fifteen patients received concurrent cisplatin therapy (40 mg/m2, q1week). Four (22.2%), seven (38.9%), and seven (38.9%) patients had stage II, III, and IV cervical cancer, respectively. Pelvic and para-aortic lymph node metastases were observed in 11 (61.1%) and 2 (11.1%) patients, respectively. The median pre-treatment volume was 87.5 cm3. The four-year local control, pelvic control, disease-free survival, and overall survival rates were 100%, 100%, 81.6%, and 87.8%, respectively. Three (16.7%) patients experienced grade 3 adverse events, and none experienced grade 4-5 adverse events. CT-MRI-guided multi-catheter interstitial brachytherapy could be a promising treatment strategy for locally advanced cervical cancer.
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Pseudohypoaldosteronism type1A (PHA1A) is the renal form of pseudohypoaldosteronism with autosomal dominant inheritance. PHA1A is caused by haploinsufficiency of the mineralocorticoid receptor, which is encoded by NR3C2. We encountered an infant who was diagnosed with PHA1A due to hyponatremia, hyperkalemia, and poor weight gain in the neonatal period. She carried a novel heterozygous mutation (NM_000901.5: c.1757 + 1 G > C) in the splice donor site of IVS-2 in NR3C2.
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Background: Monocarboxylate transporter 8 (MCT8) is a thyroid hormone transmembrane transporter protein. MCT8 deficiency induces severe X-linked psychomotor retardation. Previous reports have documented delayed myelination in the central white matter (WM) in these patients; however, the regional pattern of myelination has not been fully elucidated. Here, we describe the regional evaluation of myelination in four patients with MCT8 deficiency. We also reviewed the myelination status of previously reported Japanese patients with MCT8 deficiency based on magnetic resonance imaging (MRI). Case Reports: Four patients were genetically diagnosed with MCT8 deficiency at the age of 4-9 months. In infancy, MRI signal of myelination was observed mainly in the cerebellar WM, posterior limb of internal capsule, and the optic radiation. There was progression of myelination with increase in age. Discussion: We identified 36 patients with MCT8 deficiency from 25 families reported from Japan. The available MRI images were obtained at the age of <2 years in 13 patients, between 2 and 4 years in six patients, between 4 and 6 years in three patients, and at ≥6 years in eight patients. Cerebellar WM, posterior limb of internal capsule, and optic radiation showed MRI signal of myelination by the age of 2 years, followed by centrum semiovale and corpus callosum by the age of 4 years. Most regions except for deep anterior WM showed MRI signal of myelination at the age of 6 years. Conclusion: The sequential pattern of myelination in patients with MCT8 deficiency was largely similar to that in normal children; however, delayed myelination of the deep anterior WM was a remarkable finding. Further studies are required to characterize the imaging features of patients with MCT8 deficiency.
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INTRODUCTION: Aminoacyl-tRNA synthetase-interacting multifunctional protein 1 (AIMP1) is a non-catalytic component of the multi-tRNA synthetase complex that catalyzes the ligation of amino acids to their correct tRNAs. Bi-allelic truncating variants in the AIMP1 gene have been associated with hypomyelinating leukodystrophy-3 (HLD3; MIM 260600), which is characterized by hypomyelination, microcephaly, seizures and decreased life expectancy. Although peripheral nerve involvement has been assumed for HLD3, no compelling evidence is available to date. CASE REPORT: The case was a first-born Filipino male. He showed profound developmental delay, failure to thrive, and spasticity in his limbs. At three months of age he developed refractory epilepsy. Serial magnetic resonance imaging (MRIs) showed profound myelination delay and progressive cerebral atrophy. He showed abnormal nerve conduction studies. Genetic testing revealed a homozygous pathogenic variant in the AIMP1 gene (NM_004757.3: c.115C > T: p.Gln39*). The parents were heterozygous for the same variant. CONCLUSION: Here, we report a patient with a homozygous nonsense AIMP1 variant showing peripheral neuropathy as well as HLD3. Our case suggests that AIMP1 plays a pivotal role in the peripheral nerve as well as the central nervous system.
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Codón sin Sentido , Citocinas/genética , Discapacidades del Desarrollo/genética , Leucoencefalopatías/genética , Espasticidad Muscular/genética , Proteínas de Neoplasias/genética , Nervios Periféricos/fisiopatología , Proteínas de Unión al ARN/genética , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Discapacidades del Desarrollo/diagnóstico por imagen , Discapacidades del Desarrollo/fisiopatología , Humanos , Lactante , Leucoencefalopatías/diagnóstico por imagen , Leucoencefalopatías/fisiopatología , Imagen por Resonancia Magnética , Masculino , Espasticidad Muscular/diagnóstico por imagen , Espasticidad Muscular/fisiopatología , Conducción Nerviosa/fisiología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiopatologíaRESUMEN
Objectives Congenital hypothyroidism (CH) is the most common congenital endocrine disorder. Recent advances in genetic testing have revealed its causative mutations in some CH patients. However, the underlying etiology remains unknown in most patients. This study aimed to perform clinical and genetic investigation in Japanese CH patients to uncover genotype-phenotype correlations. Methods We enrolled 136 Japanese patients with transient or permanent CH between April 2015 and March 2017, and performed next-generation sequencing of 19 genes implicated in CH. Results We identified potentially pathogenic bi-allelic variants in DUOX2, TSHR, and TPO in 19, 5, and 1 patient, respectively (autosomal recessive), and a potentially pathogenic mono-allelic variant in NKX2-1 (autosomal dominant) in 1 patient. Molecular genetic diagnosis was highly suggested in 26 patients (19%) from 23 families. We also detected a potentially pathogenic mono-allelic variant in five recessive genes (DUOX2, TSHR, TG, DUOXA2, and TPO) in 31 unrelated patients (23%), although the pathogenicity of these variants remains inconclusive. Patients with bi-allelic DUOX2 variants showed a more severe clinical presentation in infancy than those with bi-allelic TSHR variants. However, this trend reversed beyond infancy. There were no statistical differences in initial thyroid stimulating hormone, free thyroxine, thyroglobulin, and levothyroxine dose as of March 2017 between patients with bi-allelic and mono-allelic DUOX2 variants. Conclusions The prevalence of potentially-pathogenic variants in Japanese CH patients was similar to that found by previous reports. Our study demonstrates a genotype-phenotype correlation in Japanese CH patients.