Prevalence of pseudoexfoliation in diabetic patients with senile cataract: A hospital-based study in Kashmir, India

Purpose: To study the prevalence of pseudoexfoliation syndrome (PEX) in diabetics with senile cataracts and compare it to the prevalence in nondiabetic control group. Methods: Two hundred and fifty diabetics and 250 nondiabetics (age and sex matched) were evaluated for PEX deposition. Results: Chi?squared test was employed, and a P value < 0.05 was considered significant. In the PEX group, most patients belonged to the age group of 60–70 years (55.17%). Out of 18 patients with PEX, 11 (61.1%) showed bilaterality. There was a higher frequency of raised intraocular pressure (IOP; >20 mmHg) in PEX eyes (10.3%) than in the non?PEX eyes (5.9%). The PEX group had a higher number of eyes with cup?to?disc ratio (CDR) >0.6 (11.12%) than the non?PEX group (4.32%). Nuclear cataracts were more frequent in PEX eyes than non?PEX eyes, whereas PSC and mature cataracts were more prevalent in the non?PEX group. Most eyes had PEX deposition on the anterior lens capsule and pupillary margin. Of the 500 study eyes corresponding to the diabetic group, 418 had cataracts (rest pseudophakic), of which 28 had pseudoexfoliation, accounting for 6.7% of the total. In the nondiabetic control group comprising 500 eyes, 430 had senile cataracts (rest pseudophakic), of which 105 had PEX deposition, accounting for 24.4% of the total. Conclusion: According to our findings, diabetics have a lower prevalence of PEX than nondiabetics. Few such studies have been conducted so far, and none have been conducted in the Indian population.

PEX1 gene related Zellweger syndrome: a report of 2 cases and literature review / 中国新生儿科杂志

Objective To study the phenotypic and genotypic characteristics of Zellweger syndrome caused by PEX1 gene mutation.Method The clinical data of 2 neonates with Zellweger syndrome admitted to the Hospital were retrospectively analyzed.The databases of CNKI,Wipp and Wanfang were retrieved with “peroxisomal disease”,“Zellweger syndrome”,“Zellweger pedigree disorder”,and “PEX1 gene” as key words and the human gene mutation database (HGMD) was retrieved with “PEX1” as the gene name.The biomedical literature database (PubMed),Web of Science database and Embase database were retrieved with “Zellweger syndrome”,“Zellweger spectrum disorder PEX1 gene” as key words.All the databases were retrieved up to Nov 8,2018 to summarize the clinical phenotype and genotype characteristics of children with Zellweger syndrome.Result A total of 2 neonates with Zellweger syndrome were admitted to our Hospital,including 1 male and 1 female.Both the newborns presented with hypotonia,feeding difficulties clinically and showed dilated cerebral ventricles in neuroimaging.They were detected compound heterozygous for PEX1 mutations.Case 1 with the variants [NM_000466:exon 12:c.2050C＞T (p.Q684X);NM_000466:exon20:c.3043G＞T(p.E1015X)] have suffered from seizure at 2 months old.Case 2 with the variants [NM_000466.2:exon5:c.892_895dupTATA (p.Asn299IlefsTer2);NM_000466:exon19:c.2927-2delA] died in the neonatal period.No cases of newborn Zellweger syndrome caused by PEX1 gene mutation have been reported in China.There was a total of 6 articles and 13 cases were reported from foreign literature databases.All the cases presented as hypotonia,abnormal liver function,wide sutures (large fontanelle),hypertelorism and broad nasal bridge clinically.2 newborns carrying 2 missense variants were diagnosed as mild Zellweger spectrum disorder and atypical Zellweger syndrome the 10 newborns with 2 variants typed frameshift,nonsense or splice site were diagnosed as Zellweger syndrome.Conclusion Zellweger syndrome caused by defective gene PEX1 manifested as hypotonia,abnormal liver function,wide sutures (large fontanelle),hypertelorism and broad nasal bridge in neonatal period.Newborns with frameshift,nonsense or splice site variants in PEX1 have more severe clinical phenotypical features.

Enfermedad peroxisomal, condrodisplasia rizomelica punctata tipo 1: reporte de caso / Peroxisomal disorder, rhizomelyc chondrodysplasia punctata type 1: case report

Introducción: Las enfermedades peroxisomales son un grupo de trastornos monogénicos que incluyen desórdenes en la biogénesis del peroxisoma o deficiencias enzimáticas. La Condrodisplasia Rizomélica Punctata Tipo 1 (RCDP1) pertenece al primer grupo, es autosómica recesiva originada por mutaciones del gen PEX7, que codifica para el receptor PTS2. El objetivo del presente artículo son describir una enfermedad genética de baja prevalencia, explicando sus principales características y la importancia de la aproximación diagnóstica y asesoría genética. Caso clínico: Lactante masculino de 13 meses, sin antecedentes familiares ni consanguinidad. Al nacimiento presentaba acortamiento de miembros superiores. Fue intervenido a los 7 meses por catarata bilateral. Presentaba severo retardo del crecimiento, retraso del desarrollo psicomotor, anomalías menores craneofaciales, acortamiento rizomélico de miembros superiores y en menor grado de miembros inferiores. En la radiografía se identificaban calcificaciones punteadas del cartílago en rótula. Entre los exámenes de laboratorio destacaba elevación de los ácidos grasos fitánico y pristánico. El paciente falleció a la edad de 3 años. Discusión: Esta es una enfermedad rara, la prevalencia es 1/100.000, se han descrito diferentes mutaciones del gen PEX7 teniendo variación en el fenotipo. El tratamiento es básicamente sintomático y depende de la gravedad de las manifestaciones clínicas, el tipo rizomélico es de mal pronóstico, la mayoría de los pacientes no sobrevive antes de la primera década de vida. La asesoría genética es fundamental ya que se considera un riesgo del 25% de recurrencia.

Introduction: Peroxisomal diseases are a group of monogenic disorders that include defects in peroxisome biogenesis or enzyme dificiencies. Rhizomelic chondrodysplasia punctata type 1 (RCDP1) belongs to the first group, caused by autosomal recessive mutations on PEX7 gene, encoding for PTS2 receptor. The aims of this report are to describe a genetic disease of low prevalence, explaining its main characteristics and the importance of the diagnostic approach and genetic counseling. Case report: 13-month-old male infant with no medical history, family or consanguinity, demonstrate at birth upper limbs shortening. Surgery intervention at seven months old for bilateral cataract. Growth retardation, psychomotor retardation, minor craniofacial anomalies, rhyzomelic shortened upper limbs and lower limbs lesser degree. Punctata calcifications in patella cartilage. Also fatty acid phytanic and pristanic increased levels. Patient dead at age of 3 years. Discussion: RCDP1 is a rare disease, with a prevalence of 1/100,000. Different mutations of PEX7 gene have been described, with variations in phenotype. The treatment is basically symptomatic and depends on the severity of clinical manifestations. The rhizomelic type has poor prognosis, most patients do not survive before the first decade of live. Genetic counseling is essential because it is consider a 25% risk of recurrence.

Evaluation of the role of the Endoplasmic Reticulum-Golgi transit in the biogenesis of peroxisomal membrane proteins in wild type and peroxisome biogenesis mutant CHO cells

Peroxisomes are thought to be formed by division of pre-existing peroxisomes after the import of newly synthesized proteins. However, it has been recently suggested that the endoplasmic reticulum (ER) provides an alternative de novo mechanism for peroxisome biogenesis in some cells. To test a possible role of the ER-Golgi transit in peroxisome biogenesis in mammalian cells, we evaluated the biogenesis of three peroxisomal membrane proteins (PMPs): ALDRP (adrenoleukodystrophy related protein), PMP70 and Pex3p in CHO cells. We constructed chimeric genes encoding these PMPs and green fluorescent protein (GFP), and transiently transfected them to wild type and mutant CHO cells, in which normal peroxisomes were replaced by peroxisomal membrane ghosts. The expressed proteins were targeted to peroxisomes and peroxisomal ghosts correctly in the presence or absence of Brefeldin A (BFA), a drug known to block the ER-Golgi transit. Furthermore, low temperature did not disturb the targeting of Pex3p-GFP to peroxisomes. We also constructed two chimeric proteins of PMPs containing an ER retention signal "DEKKMP": GFP-ALDRP-DEKKMP and myc- Pex3p-DEKKMP. These proteins were mostly targeted to peroxisomes. No colocalization with an ER maker was found. These results suggest that the classical ER-Golgi pathway does not play a major role in the biogenesis of mammalian PMPs.

Efficient Secretion of Recombinant PEX in COS7 Cells Directed by MMP-9 Signal Peptide / 中国生物工程杂志

With the rapidly development of the biotechnology industry,large quantities of recombinant proteins are needed for specific therapeutic and diagnostic applications.Bacterial cells are most often used for the production of recombinant proteins.However,recombinant proteins expressed in the cytoplasm of bacteria are often misfolded as insoluble inclusion bodies and therefore inactive.To circumvent this problem,several eukaryotic expression systems have also been developed over the years,ranging from yeast to mammalian cell-based technologies.For many mammalian proteins,especially those secreted and modified posttranslationally,a more compatible expression system is highly desirable because proper folding or modification can only be provided with closely related cells,i.e.,mammalian cells.Large scale transient transfection of mammalian cells is a recent and powerful technology for the fast production of milligram amounts of recombinant proteins.Transient expression by means of extrachromosomal replication in COS cells is frequently used to check the functional integrity of genes/plasmids and to produce small quantities of cell supernatants containing the protein of interest.As it is allowed for easy and efficient purification,many recombinant proteins used for therapeutic and structural studies are naturally secreted or engineered to be secreted.The use of a proper signal peptide is one of the major determinants for the efficient secretion of heterologous proteins from mammalian cells.The noncatalytic C-terminal hemopexin-like domain of MMP-2,PEX,can block angiogenesis and tumor growth in vivo.Large quantities of biochemically active recombinant PEX are required for the study of their functions and biochemical properties,as well as for their industrial applications.For this purpose,the rat growth hormone,mouse IgG? chain and MMP-9 signal peptides were used for expression of PEX in COS7 cells,and their secretion efficiencies were compared by Western blotting and ELISA.Western-blotting of PEX protein from culture media,resulted in detection of proteins with the predicted molecular mass,which indicate that all of the signal sequences could direct PEX secretion successfully.The MMP-9 signal peptide seems to be superior to the signal peptides from IgG and rGH both in terms of extracellular yield and in terms of secretion efficiency.Thus,expression of pM9PEX construct resulted in higher yields of extracellular PEX and the majority of the produced PEX was secreted and not trapped intracellularly.To examine whether the observed difference in secretion yields is promoted at the transcriptional level,a RT-PCR analysis was performed at 6 h after transfection.The presence of mRNA transcripts of PEX was observed in all the DNA constructs.Moreover,semiquantitative reverse transcription(RT-PCR)results show that there were no significant differences in the expression levels of PEX among the constructs at 6 h after transfection.Though there was no difference in the expression levels of PEX at an early time point after transfection,the presence of an ER-targeting signal peptide sequence in the expression vector affected the trafficking of expressed proteins in the cells.Hence,the described difference in exported yields is probably promoted at the secretion level,rather than at the transcriptional level.Chick chorioallantoic membrane(CAM)bioassay show that the PEX protein purified from cell culture had biological activity to inhibit the angiogenesis.The MMP-9's signal peptide is used for the first time as leader sequence for secretion of foreign proteins.The results revealed that higher amounts of secreted PEX were obtained when vectors containing MMP-9 signal peptide were used and it is also indicated that MMP-9 signal sequence could be effective on promoting the secretion of other heterologous proteins in eukaryotic cells.

Construction of a recombinant adenovirus containing MMP-9 signal peptide and PEX domain of human MMP-2 and study of its activity / 中国肿瘤生物治疗杂志

Objective: To construct a recombinant adenovirus (abbreviated as ET-M9-PEX) containing MMP-9 signal peptide and noncatalytic carboxyl-terminal hemopexin domain of human MMP-2, and to use the constructed adenovirus as a drug bioreactor in vivo to enhance the expression of an anti-angiogenesis factor for treatment of tumor by a gene therapy strategy. Methods: Adenovirus vector containing M9-PEX gene was constructed by PCR and gene recombination, and was packaged and amplified in L293 cells to obtain ET-M9-PEX recombinant adenovirus with infective ability. The expression and secretion of PEX in ET-M9-PEX-infected cells were detected by Western-blotting and immunofluorescent staining. The inhibitory effect of ET-M9-PEX-conditioned medium on EC cells proliferation was detected by growth curve and its inhibitory effects on angiogenesis and tumor growth were determined by chicken chorioallantoic membrane (CAM) assay in vivo. Results:ET-M9-PEX was successfully constructed and the expression and secretion of PEX in ET-M9-PEX-infected cells were verified. The ET-M9-PEX conditioned medium significantly inhibited the proliferating rate of EC cells. The tumor weights from ET-M9-PEX-infected PG cells in CAM and gradeⅠvessel number were reduced by 57.57%(P