Peripheral nerves are involved in hypomyelinating leukodystrophy-3 caused by a homozygous AIMP1 variant

IntroductionAminoacyl-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 reportThe 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.ConclusionHere, 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.     

Schwannoma mimicking pancreatic carcinoma: A case report

BACKGROUNDSchwannoma of the pancreas is extremely rare. We report a case of pancreatic schwannoma that was difficult to distinguish from pancreatic carcinoma before surgery.CASE SUMMARYA 66-year-old male underwent a right-lobe hepatectomy for hepatocellular carcinoma. Post-surgical computed tomography showed a 10 mm long solid mass with ischemia, with no expansion into the main pancreatic duct. Upon magnetic resonance cholangiopancreatography, the tumor had high signal intensity in diffusion weighted images, consistent with pancreatic carcinoma. Endoscopic ultrasound (EUS) was performed to obtain more information about the tumor, and showed a 14 mm solid and hypoechoic mass in the pancreatic body. Contrast enhanced EUS revealed that the tumor showed a hyperechoic mass in the early phase, and the contrasting effect continuation was very short; findings also consistent with pancreatic carcinoma. Thus, we preoperatively diagnosed his condition as a pancreatic carcinoma and performed distal pancreatectomy with splenectomy. Microscopic examination showed that the tumor was in fact a benign schwannoma. Histology showed a proliferation of spindle-shaped cell in a vague fascicular and haphazard pattern, with palisading arrangement.CONCLUSIONSchwannoma of the pancreas is very rare, however, clinicians should consider schwannoma as the differential diagnosis for pancreatic tumors.     

Association of aging and tooth loss with masseter muscle characteristics: an ultrasonographic study

Clinical Oral Investigations - This study aimed to investigate the relationship between aging and tooth loss on masseter muscle quantity and quality. This cross-sectional study was conducted among...     

Influence of differences in the hardness and calcium content of diets on the growth of craniofacial bone in rats

Objective:To examine the effects of a soft diet and a low-calcium diet on the craniofacial growth and bone architectures of the maxilla and mandible.Materials and Methods:Male rats (n  =  20, 3 weeks old) were divided into four groups. Ten rats were given a normal-calcium diet, and the other rats were given a low-calcium diet. Each group was then divided into two subgroups, which were fed a hard or a soft diet. After 4 weeks, craniofacial growth and architecture in maxillary and mandibular bone were analyzed using cephalometry, micro-computed tomography, and histopathology.Results:The low-calcium diet had no effect on serum calcium levels. The low-calcium diet had the greatest effect on craniofacial bone growth, while the soft diet affected the growth of several bone sites that are attached to the masseter muscle. A low-calcium diet resulted in the deterioration of the connectivity of the trabeculae in the furcation region of the maxillary and mandibular first molar, while a soft diet resulted in the diffuse disappearance of trabeculae in the central part of the furcation regions. In the midpalatal suture, a low-calcium diet resulted in inhibition of cartilaginous ossification, although the midpalatal suture had a normal cartilaginous structure. A soft diet resulted in narrower cartilage cell layers in the midpalatal suture.Conclusions:We demonstrated that a low-calcium diet and a soft diet resulted in a deterioration of bone structures in both the maxilla and in the mandible; however, the mechanisms underlying these effects differed between diets.     

Clinical outcomes of a novel therapeutic vaccine with Tax peptide‐pulsed dendritic cells for adult T cell leukaemia/lymphoma in a pilot study

Adult T cell leukaemia/lymphoma (ATL) is a human T cell leukaemia virus type‐I (HTLV‐I)‐infected T cell malignancy with poor prognosis. We herein developed a novel therapeutic vaccine designed to augment an HTLV‐I Tax‐specific cytotoxic T lymphocyte (CTL) response that has been implicated in anti‐ATL effects, and conducted a pilot study to investigate its safety and efficacy. Three previously treated ATL patients, classified as intermediate‐ to high‐risk, were subcutaneously administered with the vaccine, consisting of autologous dendritic cells (DCs) pulsed with Tax peptides corresponding to the CTL epitopes. In all patients, the performance status improved after vaccination without severe adverse events, and Tax‐specific CTL responses were observed with peaks at 16–20 weeks. Two patients achieved partial remission in the first 8 weeks, one of whom later achieved complete remission, maintaining their remission status without any additional chemotherapy 24 and 19 months after vaccination, respectively. The third patient, whose tumour cells lacked the ability to express Tax at biopsy, obtained stable disease in the first 8 weeks and later developed slowly progressive disease although additional therapy was not required for 14 months. The clinical outcomes of this pilot study indicate that the Tax peptide‐pulsed DC vaccine is a safe and promising immunotherapy for ATL.