VPS13B gene variation and clinical phenotype of Cohen syndrome in a Chinese Han family / 中华实验眼科杂志

Objective:To analyze the pathogenicity and clinical characteristics of patients with Cohen syndrome caused by a compound heterozygous variation of VPS13B gene. Methods:A pedigree investigation was conducted.A Chinese Han family with Cohen syndrome was recruited from Henan Eye Hospital in September 2021.There were three members of two generations in this family, including one patient.The clinical data of the proband and his parents were collected, and the relevant ophthalmic and general examinations were performed to evaluate the clinical phenotype.The peripheral venous blood samples of the family members were collected to extract whole genomic DNA, and the whole exome sequencing was performed.Sanger sequencing and pedigree co-segregation analysis were performed among the family members.According to the ACMG guidelines, the pathogenicity of the selected variants was evaluated and the online tools were used to predict the pathogenicity of the variants.Relevant literature of Cohen syndrome were retrieved in Online Mendelian Inheritance in Man (OMIM) and PubMed, China National Knowledge Infrastructure and Wanfang databases by taking Cohen syndrome and VPS13B gene as the searching keywords.The clinical manifestations and pathogenic variants of patients in the literature were summarized, and the relationship between genotype and clinical phenotype was analyzed.This study protocol adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Henan Eye Hospital (No.HNEECKY-2019[15]). Both the subject and the patient's guardian were aware of the study purpose and method.Written informed consent was obtained. Results:The family was consistent with autosomal recessive inheritance.The proband, a 5-year-old male, had bilateral night blindness with photophobia, ptosis, lower eyelid entropion, and trichiasis; high myopia in both eyes; osteoblastoid pigmentation in the peripheral retina, atrophy and thinning of the outer layer of the peripheral retina, extinguished flashing electroretinogram; global growth retardation, typical facial features, slender fingers and toes, flatfoot, foot valgus, dystonia, no cardiac abnormalities; excessively cheerful personality.The clinical manifestations of the proband were consistent with Cohen syndrome.No obvious abnormality was found in the clinical phenotype and the auxiliary examination of the proband's parents.Whole exon sequencing revealed that the proband carried two heterozygous variations, a nonsense variation c. 11713C>T(p.Gln3905*) and a splicing variation c. 6940+ 1G>T.Sanger sequencing confirmed that the above variations were co-segregated in this family.c.11713C>T(p.Gln3905*) was a novel variant, which prematurely terminated the protein encoded by it and affected the normal function of the protein.The two variations were pathogenic variants according to the ACMG guidelines.A total of 12 articles on variants and clinical characteristics of Cohen syndrome in China were retrieved.Combined with the results of this study, a total of 24 VPS13B variants were found in Chinese patients, of which the incidence of frameshift variation was 41.7%(10/24), missense variation 20.8%(5/24), splicing variation 20.8%(5/24) and nonsense variation 16.7%(4/24), respectively.The onset age of patients with Cohen syndrome was from 28 days to 12 years old.The symptoms such as nerve system, eye, brain, and bone were sporadic, and the clinical manifestations were highly heterogeneous. Conclusions:A novel pathogenic variation c. 11713C>T is found in the VPS13B gene of the Cohen syndrome pedigree in this study, and expands the pathogenic variation spectrum of the VPS13B gene.The clinical manifestations of Cohen syndrome are highly heterogeneous.

Síndrome de Cohen: reporte de caso y revisión de la literatura / Cohen syndrome: case report and literature review

Resumen Introducción: el Síndrome de Cohen es una enfermedad genética monogénica autosómica recesiva, que se origina a partir de mutaciones en el gen VPS13B (COH1). Se caracteriza por obesidad, retraso psicomotor, microcefalia, hipotonía, miopía progresiva, distrofia retiniana, neutropenia intermitente y rasgos faciales particulares. Objetivo: presentar el segundo caso reportado en Colombia, que fue confirmado mediante estudio molecular. También se presenta una breve revisión de la literatura médica más reciente sobre esta patología. Caso clínico: adolescente de 14 años con microcefalia, trastorno cognitivo, malformaciones menores asociadas, neutropenia y obesidad, con mutación homocigota del gen VPS13B. Conclusión: a pesar de ser un síndrome poco común, con importante variabilidad fenotípica, debe sospecharse con base en los criterios clínicos y en las patologías asociadas.

Abstract Introduction: cohen's syndrome is an autosomal recessive monogenic genetic disease, which originates from mutations in the VPS13B (COH1) gene. It is characterized by obesity, psychomotor retardation, microcephaly, hypotonia, progressive myopia, retinal dystrophy, intermittent neutropenia, and classic facial features. Objective: to present the second case reported in Colombia, which was confirmed by molecular study. A brief review of the most recent medical literature on this pathology is also presented. Clinical case: a 14-year-old adolescent with microcephaly, cognitive disorder, minor associated malformations, neutropenia, and obesity, with a homozygous VPS13B gene mutation. Conclusion: despite being a rare syndrome, with significant phenotypic variability, it should be suspected based on clinical criteria and associated pathologies.

Effects of the S1PR3 specific agonist peptide GPS-725.017 on acute lung injury in mice / 中华急诊医学杂志

Objective:To design a modified S1PR3 specific agonist, GPS-725.017, and investigate its protective effect on acute lung injury by promoting macrophage clearance of bacteria.Methods:A short peptide derived from the intracellular region of S1PR3 receptor was named GPS725.017, which was modified with norleucine (Nle) and myristicacid (myr) at its N terminus. Mice were divided into the sham operation group, solvent group and GPS-725.017 treatment group. The acute lung injury model was induced by endotracheal injection of E. coli (5×10 6 CFU), and the experimental group was treated with GPS-725.017 (10 mg/kg). The 48-h survival rate of mice was recorded. After 5 h of modeling, the bacterial load and inflammatory cytokines in peripheral blood and lung were detected, and Vps34 protein content in alveolar macrophages was determined by Western blot. After 12-h of modeling, lung tissues were collected for H&E staining and pathological scores. Results:Compared with the solvent group, the survival rate of mice in the GPS-725.017 treatment group was significantly improved ( P<0.01), the bacterial CFU in blood and alveolar lavage fluid was significantly lower than that in the solvent group ( P<0.001), and the levels of TNF-α and IL-1β in blood and alveolar lavage fluid were significantly lower than those in the solvent group ( P<0.001). Western blot showed that the expression level of Vps34 protein in alveolar macrophages was significantly higher than that in the solvent group ( P<0.01). Histopathology result showed that the pathological damage of lung in the treatment group was significantly less than that in the solvent group ( P<0.001). Conclusions:The modified synthetic S1PR3 specific agonist GPS-725.017 could specifically activate the S1PR3 receptor on the membrane of alveolar macrophages and up-regulate the expression level of intracellular Vps34 protein, which can promote the removal of bacteria in alveolar macrophages, significantly reduce the degree of lung injury and improve the survival rate in ALI mice.

Expressions of cytokeratin 14 and proliferating cell nuclear antigen in the Hertwig's epithelial root sheath of a Vps4b knockout mouse / 华西口腔医学杂志

OBJECTIVES@#The effect of Vps4b gene mutation on the expressions of cytokeratin 14 (CK14) and proliferating cell nuclear antigen (PCNA) in the Hertwig's epithelial root sheath (HERS) is investigated.@*METHODS@#The bilateral mandibular tissues of mouse on postnatal days 5, 9, 11, 15, and 19 were removed. The mandibular first molar tissue sections were obtained after paraffin embedding. The CK14 and PCNA expressions in the epithelial root sheath of the normal mouse and Vps4b knockout mouse were compared through immunohistochemistry.@*RESULTS@#On postnatal day 5, the normal mouse began to form HERS and had a strong positive PCNA expression in the HERS cells; on postnatal day 9, the HERS structure was continuous, and PCNA was positive in the HERS cells; on postnatal day 11, a small portion of HERS began to break, and PCNA was weakly positive in the HERS cells; on postnatal day 15, HERS continued to fracture; PCNA was weakly and positively expressed in the HERS cells on the root surface; on postnatal day 19, the tooth root reached normal physiological length, and PCNA was positively expressed in the HERS cells of the terminal part. Similar to the normal mouse, the gene knockout mouse also formed a HERS structure on postnatal day 5. However, HERS began to break on postnatal day 9. On postnatal day 19, only a few fragments of HERS were found on the root surface, and the root development was immature. Moreover, the expression intensity of PCNA in the gene knockout mouse was decreased.@*CONCLUSIONS@#The Vps4b gene mutation may change the CK14 and PCNA expressions, leading to abnormal root development.

Clinical study of two-trocar laparoscopy-assisted ventriculoperitoneal shunt in the treatment of hydrocephalus / 上海交通大学学报（医学版）

Objective • To compare the clinical outcomes between two-trocar laparoscopy-assisted ventriculoperitoneal shunt (LAVPS) and conventional open ventriculoperitoneal shunt (OVPS), and explore the clinical practice and experience of the placement of distal catheter in two-trocar LAVPS. Methods • A total of 308 patients with hydrocephalus who underwent ventriculoperitoneal shunt (VPS) from January 2016 to December 2018 in the Department of Neurosurgery at Renji Hospital, Shanghai Jiao Tong University School of Medicine were analyzed retrospectively. Among them, there were 90 patients in the LAVPS group (Group L), and the two-trocar method and the original suture loop method were adopted to place the distal catheter in the right hepato-diaphragmatic space. For the other 218 patients in the conventional OVPS group (Group O), the laparotomy approach was adopted to put the distal catheter into the left lower abdominal cavity through the midline incision. The operation time and complications of the distal catheter between the two groups were compared. Results • Compared with Group O, the mean operation time was significantly reduced in Group L (54 min vs 90 min, P=0.000), and the incidence of distal catheter complications was also significantly decreased (0 vs 9.6%, P=0.002). In Group L, only one case of visceral injury, one case of distal catheter migration and one case of proximal catheter obstruction occurred. The incidences of infection and obstruction of the distal catheters were 0 in Group L, significantly lower than those in Group O (0 vs 4.6%, P=0.039; 0 vs 5.0%, P=0.030). In Group O, 10 cases of distal catheter infection, 11 cases of obstruction, 4 cases of visceral injury and 2 cases of incisional hernia occurred. Conclusion • The modified two-trocar LAVPS, of which the distal catheter was guided by a suture loop method and placed in the right hepato-diaphragmatic space, is a safe, economical and simple surgical procedure that is more effective in treating hydrocephalus of various origins than conventional OVPS.

Spatial Learning and Motor Deficits in Vacuolar Protein Sorting-associated Protein 13b (Vps13b) Mutant Mouse

Vacuolar protein sorting-associated protein 13B (VPS13B), also known as COH1, is one of the VPS13 family members which is involved in transmembrane transport, Golgi integrity, and neuritogenesis. Mutations in the VPS13B gene are associated with Cohen syndrome and other cognitive disorders such as intellectual disabilities and autism spectrum disorder (ASD). However, the patho-physiology of VPS13B-associated cognitive deficits is unclear, in part, due to the lack of animal models. Here, we generated a Vps13b exon 2 deletion mutant mouse and analyzed the behavioral phenotypes. We found that Vps13b mutant mice showed reduced activity in open field test and significantly shorter latency to fall in the rotarod test, suggesting that the mutants have motor deficits. In addition, we found that Vps13b mutant mice showed deficits in spatial learning in the hidden platform version of the Morris water maze. The Vps13b mutant mice were normal in other behaviors such as anxiety-like behaviors, working memory and social behaviors. Our results suggest that Vps13b mutant mice may recapitulate key clinical symptoms in Cohen syndrome such as intellectual disability and hypotonia. Vps13b mutant mice may serve as a useful model to investigate the pathophysiology of VPS13B-associated disorders.

Spatio-temporal expression of dentin sialophosphoprotein and collagen Ⅰ during molar tooth germ development in vps4b knockout mouse / 华西口腔医学杂志

OBJECTIVE@#To verify the effect of the mutant gene vps4b on the expression of tooth development-related proteins, dentin sialophosphoprotein (DSPP) and collagenⅠ (COL-Ⅰ).@*METHODS@#Paraffin tissue sections of the first molar tooth germ were obtained from the heads of fetal mice at the embryonic stages of 13.5, 14.5, and 16.5 days and from the mandibles of larvae aged 2.5 and 7 days after birth. The immunohistochemical method was used to detect the expression and location of DSPP and COL-Ⅰ in wild-type mouse and vps4b knockout mouse.@*RESULTS@#DSPP and COL-Ⅰ were not found in the bud and cap stages of wild-type mouse molar germ. In the bell stage, DSPP was positively expressed in the inner enamel epithelium and dental papilla, whereas COL-Ⅰ was strongly expressed in the dental papilla and dental follicle. During the secretory and mineralized periods, DSPP and COL-Ⅰ were intensely observed in ameloblasts, odontoblasts, and dental follicles, but COL-Ⅰ was also expressed in the dental papilla. After vps4b gene knockout, DSPP was not expressed in the dental papilla of the bell stage and in the dental papilla and dental follicle of the secretory phase. The expression position of COL-Ⅰ in the bell and mineralization phase was consistent with that in the wild-type mice. Moreover, the expression of COL-Ⅰ in the dental papilla changed in the secretory stage.@*CONCLUSIONS@#Gene vps4b plays a significant role in the development of tooth germ. The expression of DSPP and COL-Ⅰ may be controlled by gene vps4b and regulates the development of tooth dentin and cementum together with vps4b.

A Novel VPS33B Variant Identified by Exome Sequencing in a Patient with Arthrogryposis-Renal Dysfunction-Cholestasis Syndrome / 대한소아소화기영양학회지

Arthrogryposis-renal dysfunction-cholestasis (ARC) syndrome is a rare autosomal recessive multisystemic disease that is associated with the liver, kidney, skin, and central nervous and musculoskeletal systems. ARC occurs as a result of mutations in the VPS33B (Vacuolar protein sorting 33 homolog B) or VIPAR (VPS33B interacting protein, apical-basolateral polarity regulator) genes. A female infant presented with neonatal cholestasis with a severe clinical outcome. She was diagnosed with ARC syndrome using targeted exome sequencing (TES). Exome sequencing revealed compound heterozygous mutations, c.707A>T and c.239+5G>A, in VPS33B, where c.707A>T was a novel variant; the resultant functional protein defects were predicted via in silico analysis. c.239+5G>A, a pathogenic mutation that affects splicing, is found in less than 0.1% of the general population. Invasive techniques, such as liver biopsies, did not contribute to a differential diagnosis of ARC syndrome; thus, early TES together with clinical presentations constituted an apparently accurate diagnostic procedure.

Ascitis por líquido cefalorraquideo secundario a derivación ventriculo-peritoneal / Cerebrospinal fluid ascites secondary to ventriculo - expert neal

La ascitis por Líquido cefalorraquídeo es una complicación relativamente rara que se ha reportado en la literatura prácticamente desde 1972. Junto con el pseudoquiste abdominal corresponde a un 2% de las complicaciones de las derivaciones ventriculoperitoneales. Múltiples teorías han intentado explicar la patogenia de esta patología. A continuación se presenta el caso de un paciente de 36 años del Hospital México quien luego de 11 años de colocada una DVP desarrolla un cuadro de ascitis por LCR cuyos estudios clínicos no mostraron causa desencadenante evidente del cuadro por lo que fue necesario realizar una derivación ventrículo-atrial. Se incluye además una revisión de la literatura vigente.

Ascites by cerebrospinal fluid (CSF) is a relatively rare complication that has been reported in the literature almost since 1972. Along with abdominal pseudocyst corresponds to 2% of the complications of ventriculoperitoneal shunts (VPS) . Multiple theories have attempted to explain the pathogenesis of this disease. Then the case of a patient of 36 years of the Hospital Mexico who after 11 years VPS placed one develops a picture of ascites CSF is presented whose clinical studies showed no obvious precipitating cause it was necessary to perform a ventriculo -atrial shunt. A review of the current literature is also included.

Vps1 in the late endosome-to-vacuole traffic.

Vacuolar protein sorting 1 (Vps1), the yeast homolog to human dynamin, is a GTP hydrolyzing protein, which plays an important role in protein sorting and targeting between the Golgi and late endosomal compartments. In this study, we assessed the functional significance of Vps1 in the membrane traffic towards the vacuole. We show here that vps1Δ cells accumulated FM4-64 to a greater extent than wild-type (WT) cells, suggesting slower endocytic degradation traffic toward the vacuole. In addition, we observed that two endosome-to-vacuole traffic markers, DsRed-FYVE and Ste2-GFP, were highly accumulated in Vps1-deficient cells, further supporting Vps1’s implication in efficient trafficking of endocytosed materials to the vacuole. Noteworthy, a simultaneous imaging analysis in conjunction with FM4-64 pulse-chase experiment further revealed that Vps1 plays a role in late endosome to the vacuole transport. Consistently, our subcellular localization analysis showed that Vps1 is present at the late endosome. The hyperaccumulation of endosomal intermediates in the vps1 mutant cells appears to be caused by the disruption of integrity of HOPS tethering complexes, manifested by mislocalization of Vps39 to the cytoplasm. Finally, we postulate that Vps1 functions together with the Endosomal Sorting Complex Required for Transport (ESCRT) complex at the late endosomal compartments, based on the observation that the double mutants, in which VPS1 along with singular ESCRT I, II and III genes have been disrupted, exhibited synthetic lethality. Together, we propose that Vps1 is required for correct and efficient trafficking from the late endosomal compartments to the vacuole.

Factores de riesgo de infección de derivativa ventrículo peritoneal en pacientes pediátricos del Hospital Carlos Van Buren / Risk factors for ventricular peritoneal shunt infection in pediatric patients from the hospital Carlos Van Buren

Hydrocephalus is a common problem in Neurosurgery and Neurology. The usual treatment is the installation of a Ventricular Peritoneal Shunt (VPS). Infection is the most frequent and serious complication. With the aim to identify risk factors associated with infection in the post surgery of VPS in pediatric patients from Carlos Van Buren Hospital a case control study between 1998-2008 was done. Cases were patients with VPS infection reported to the Department of Nosocomial Infections. Results in contingency tables were analyzed to determine Odds Ratio. 264 surgical procedures were studied in 207 patients with 53 infections reported in 26 patients. Significant risk factors were: history of prior ventriculitis, VPS dysfunction and prior external ventricular shunt, concurrent infections at the time of surgery and a neurosurgeon without the specialty of pediatric neurosurgery. We concluded that antibiotic prophylaxis was not an important factor in preventing infection and the neurosurgeon experience is relevant to the development of VPS infections.

La hidrocefalia es un problema común en neurocirugía y neurología. Su tratamiento habitual es la instalación de una válvula derivativa ventrículo peritoneal (DVP) cuya complicación más grave y frecuente es la infección. Con el propósito de identificar los factores de riesgo de infección post-operatoria en pacientes con DVP del Hospital Carlos Van Buren (HCVB), se realizó un estudio caso-control en la población pediátrica con DVP instalada entre 1998 y 2008. Los casos fueron pacientes con una infección de DVP notificada en el Departamento de Infecciones Intrahospitalarias (IIH), y controles los que no presentaron infección. Se analizaron los resultados en tablas de contingencia para determinar los Odds Ratio correspondientes. Se estudiaron 264 procedimientos quirúrgicos, 207 pacientes y 53 infecciones notificadas en 26 enfermos. Los factores de riesgo significativos fueron el antecedente de ventriculitis previa, disfunción de DVP previa, derivativa ventricular externa previas, infecciones concomitantes al momento de la cirugía, y que el neurocirujano no tuviera la especialidad en neurocirugía pediátrica. Se concluyó que la profilaxis antimicrobiana no fue un factor importante en la prevención de infecciones y que la experiencia del neurocirujano es relevante en el desarrollo de infecciones de DVP.

Accuracy of five implant impression technique: effect of splinting materials and methods

PURPOSE: The aim of this study was to evaluate the effect of dimensional stability of splinting material on the accuracy of master casts. MATERIALS AND METHODS: A stainless steel metal model with 6 implants embedded was used as a master model. Implant level impressions were made after square impression copings were splinted using 5 different techniques as follows. (1) Splinted with autopolymerizing resin and sectioned, reconnected to compensate polymerization shrinkage before the impression procedure. (2) Splinted with autopolymerizing resin just before impression procedure. (3) Primary impression made with impression plaster and secondary impression were made over with polyether impression material. (4) Splinted with impression plaster. (5) Splinted with VPS bite registration material. From master model, 5 impressions and 5 experimental casts, total 25 casts were made for each of 5 splinting methods. The distortion values of each splinting methods were measured using coordinate measuring machine, capable of recordings in the x-, y-, z-axes. A one-way analysis of variance (ANOVA) at a confidence level of 95% was used to evaluate the data and Tukey's studentized range test was used to determine significant differences between the groups. RESULTS: Group 1 showed best accuracy followed by Group 3 & 4. Group 2 and 5 showed relatively larger distortion value than other groups. No significant difference was found between group 3, 4, 5 in x-axis, group 2, 3, 4 in y-axis and group 1, 3, 4, 5 in z-axis (P<.0001). CONCLUSION: Both Splinting impression copings with autopolymerizing resin following compensation of polymerization shrinkage and splinting method with impression plaster can enhance the accuracy of master cast and impression plaster can be used simple and effective splinting material for implant impression procedure.