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1.
Front Cell Dev Biol ; 11: 1151672, 2023.
Article in English | MEDLINE | ID: mdl-37363721

ABSTRACT

Ovastacin (ASTL), a zinc metalloprotease, is released from a fertilized egg during exocytosis of cortical granules which occurs minutes after the sperm and egg fuse. ASTL cleaves ZP2, one of the four primary glycoproteins of human zona pellucida, and this cleavage prevents polyspermy, causes zona pellucida hardening, and also protects the pre-implantation embryo. Any perturbation in the activity of ASTL can thus disturb this process and may lead to infertility without changing the gross morphology of the oocyte. A small amount of ASTL is also released by unfertilized oocytes but its catalytic activity is absent as it is bound by its inhibitor, Fetuin-B (FETUB). Pre-mature release of ASTL when FETUB is absent also causes infertility. To identify and understand the structural and functional effects of deleterious SNPs of ASTL on its interaction with ZP2 and FETUB and hence on fertility, a total of 4,748 SNPs from the dbSNP database were evaluated using a variety of in silico tools. All of the 40 shortlisted nsSNPs were present in the catalytic domain of the protein. Comparison of the wild type with mutants using MutPred2 suggests an alteration in the catalytic activity/zinc binding site in many SNPs. Docking studies show the involvement of hydrophobic interactions and H bonding between ASTL and ZP2 and also between ASTL and FETUB. Four positions in ASTL involved in the hydrophobic interactions (P105 and D200 between ASTL and ZP2; D198 and L278 between ASTL and FETUB) and 5 in H bonding (E75 and R159 between ASTL and ZP2; and K93, R159, and C281 between ASTL and FETUB) have SNP's associated with them validating their importance. Interestingly, a cluster of multiple SNPs was found in the motif 198DRD200, which is also a well-conserved region among several species. Statistical Coupling Analysis (SCA) suggested that the deleterious SNPs were present in the functionally important amino acid positions of ASTL and are evolutionarily coupled. Thus, these results attempt to identify the regions in ASTL, mutations in which can affect its binding with ZP2 or FETUB and cause female infertility.

2.
Biol Open ; 11(8)2022 08 15.
Article in English | MEDLINE | ID: mdl-36039864

ABSTRACT

Individual differences in exploratory behavior have been found across a range of taxa and are thought to contribute to evolutionary fitness. Animals that explore more of a novel environment and visit areas of high predation risk are considered bold, whereas animals with the opposite behavioral pattern are shy. Here, we determined whether this bimodal characterization of bold versus shy adequately captures the breadth of behavioral variation in zebrafish or if there are more than these two subtypes. To identify behavioral categories, we applied unsupervised machine to three-dimensional swim traces from over 400 adult zebrafish across four strains (AB, TL, TU, and WIK) and both sexes. We found that behavior stratified into four distinct clusters: previously described bold and shy behavior and two new behavioral types we call wall-huggers and active explorers. Clusters were stable across time and influenced by strain and sex where we found that TLs were shy, female TU fish were bold, male TU fish were active explorers, and male ABs were wall-huggers. Our work suggests that zebrafish exploratory behavior has greater complexity than previously recognized and lays the groundwork for the use of zebrafish in understanding the biological basis of individual differences in behavior.


Subject(s)
Exploratory Behavior , Zebrafish , Animals , Female , Male , Swimming
3.
Front Cell Dev Biol ; 9: 763166, 2021.
Article in English | MEDLINE | ID: mdl-34869353

ABSTRACT

ZP2, an important component of the zona matrix, surrounds mammalian oocytes and facilitates fertilization. Recently, some studies have documented the association of mutations in genes encoding the zona matrix with the infertile status of human females. Single nucleotide polymorphisms are the most common type of genetic variations observed in a population and as per the dbSNP database, around 5,152 SNPs are reported to exist in the human ZP2 (hZP2) gene. Although a wide range of computational tools are publicly available, yet no computational studies have been done to date to identify and analyze structural and functional effects of deleterious SNPs on hZP2. In this study, we conducted a comprehensive in silico analysis of all the SNPs found in hZP2. Six different computational tools including SIFT and PolyPhen-2 predicted 18 common nsSNPs as deleterious of which 12 were predicted to most likely affect the structure/functional properties. These were either present in the N-term region crucial for sperm-zona interaction or in the zona domain. 31 additional SNPs in both coding and non-coding regions were also identified. Interestingly, some of these SNPs have been found to be present in infertile females in some recent studies.

4.
Biol Reprod ; 103(6): 1171-1185, 2020 12 01.
Article in English | MEDLINE | ID: mdl-32761117

ABSTRACT

Mammalian fertilization involves a physical interaction between a sperm and an egg followed by molecular interactions amongst their various cell surface molecules. These interactions are initially mediated on the egg's outermost matrix, zona pellucida (ZP), and then its plasma membrane. To better understand this process, it is pertinent to find the corresponding molecules on sperm that interact with ZP or the egg's plasma membrane. Although currently, we have some knowledge about the binding partners for egg's plasma membrane on sperm, yet the ones involved in an interaction with ZP have remained remarkably elusive. This review provides comprehensive knowledge about the various sperm proteins participating in mammalian fertilization and discusses the possible reasons for not being able to identify the strong sperm surface candidate (s) for ZP adhesion. It also hypothesizes the existence of a multi-protein complex(s), members of which participate in oviduct transport, cumulus penetration, zona adhesion, and adhesion/fusion with the egg's plasma membrane; with some protein(s) having multiple roles during this process. Identification of these proteins is crucial as it improves our understanding of the process and allows us to successfully treat infertility, develop contraceptives, and improve artificial reproductive technologies.


Subject(s)
Fertilization/physiology , Mammals/physiology , Spermatozoa/metabolism , Animals , Male , Sperm-Ovum Interactions/physiology
5.
Compend Contin Educ Dent ; 39(7): e1-e4, 2018.
Article in English | MEDLINE | ID: mdl-30020795

ABSTRACT

The purpose of this article is to report a digital workflow protocol for full-arch implant rehabilitation from guided surgery to final prosthesis in only three visits. This expedited protocol allows for implant placement with a surgical template generated from preoperative virtual planning and production of the CAD/CAM prosthodontic rehabilitation using a digital workflow. At the first visit, a guided implant placement protocol with the All-on-4 concept and immediate loading with the conversion prosthesis technique was done. At the same visit, final impression and interocclusal records, cast verification and mounting, as well as digital scanning of the conversion prosthesis were carried out. During the second visit, the framework try-in was performed. Lastly, the third visit included delivery of the final full-arch prosthesis opposed by a maxillary complete denture.


Subject(s)
Computer-Aided Design , Denture Design , Denture, Complete , Aged , Humans , Male , Surgery, Computer-Assisted , Workflow
6.
J Esthet Restor Dent ; 29(3): 178-188, 2017 May 06.
Article in English | MEDLINE | ID: mdl-28316122

ABSTRACT

OBJECTIVE: To present a rationale to reduce treatment complexity, number of surgeries, and overall treatment time for patients with extreme mandibular ridge deficiency. CLINICAL CONSIDERATIONS: A 67-year-old fully edentulous male presented with a chief complaint of poor retention and stability of the mandibular complete denture with consequent discomfort and inability to chew. A novel 3-appointment protocol from guided implant placement to definitive prosthesis delivery was implemented. At the first appointment, a guided surgery protocol with the All-on-4 concept was used in the mandible. Implant placement was followed by immediate loading with a fixed provisional prosthesis providing the patient with immediate function. Final impression, cast verification and articulation, determination of VDO, and interocclusal records were obtained in the same appointment. In the second appointment, the framework try-in was performed and a pick-up impression was taken after a new CR record. The third appointment included the delivery of the final screw-retained, one-piece, full-arch prosthesis opposed by a maxillary complete denture. CONCLUSION: This expedited protocol allows for implant placement with a surgical template generated from preoperative virtual planning of the implants and the CAD/CAM prosthodontic rehabilitation using a digital workflow. The patient was satisfied with the esthetic and functional outcome and was enrolled into a 6-month recall program. CLINICAL SIGNIFICANCE: This article describes an expedited protocol illustrating a digital workflow for full arch implant rehabilitation of the extremely atrophic mandible. Flapless implant placement with a surgical template generated from virtual planning was followed by immediate loading with a fixed prosthesis. Digital impression/digitization of the working cast and CAD/CAM technology were used to mill the definitive prosthesis. From guided surgery to the definitive rehabilitation only three appointments were necessary. This digital workflow can enhance patient acceptance and comfort and serve as an alternative treatment in the indicated clinical scenario. (J Esthet Restor Dent 29:178-188, 2017).


Subject(s)
Dental Prosthesis, Implant-Supported , Denture, Complete, Lower , Immediate Dental Implant Loading/methods , Jaw, Edentulous/rehabilitation , Aged , Denture Design , Humans , Male , Mandible , Workflow
7.
Int J Med Chem ; 2012: 237965, 2012.
Article in English | MEDLINE | ID: mdl-25374684

ABSTRACT

Benzodiazepines have a various behavioral effects in addition to their anxiolytic action. There is every reason to believe that the BZ/GABA receptor complex is involved in these effects, since GABAmimetic manipulations modify the effect of BZ in tests of convulsive activity, motor function, and appetitive behavior. 1,5-Benzodiazepines are biologically important molecules and are extensively used clinically as analgesic, hypnotic, sedative, and antidepressive agents. Hence, 1,5-Benzodiazepines were synthesized by condensation of o-phenylenediamine and ketones, for example, cyclohexanone and acetone in presence of sulfated zirconia (catalyst). Mannich bases were synthesized with acetophenone, p-nitroacetophenone, p-chloroacetophenone, and formaldehyde. Schiff bases were synthesized using Mannich base of 1,5-benzodiazepines with p-chloroaniline and p-chlorophenylsemicarbazide in the presence of glacial acetic acid. All the synthesized compounds were characterized by (1)H NMR and IR spectral analyses. All the synthesized derivatives were evaluated at the dose of 30 mg/kg b.w for anticonvulsant activity by isoniazid induced convulsion model, and the compounds NBZD-3 and NBZD-8 were found to be the most active among all compounds. Among all the synthesized derivatives, compounds NBZD-13 and NBZD-17 were found to be the most active among all compounds using thiosemicarbazide induced model. Although NBZD-8, NBZD-10, and NBZD-18 are the compounds which had shown good anticonvulsant activity and have an advantage over that, they were not sedative.

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