Identification and characterization of calcium binding protein, spermatid-associated 1 (CABS1)# in selected human tissues and fluids.

Calcium binding protein, spermatid associated 1 (CABS1) is a protein most widely studied in spermatogenesis. However, mRNA for CABS1 has been found in numerous tissues, albeit with little information about the protein. Previously, we identified CABS1 mRNA and protein in human salivary glands and provided evidence that in humans CABS1 contains a heptapeptide near its carboxyl terminus that has anti-inflammatory activities. Moreover, levels of an immunoreactive form of CABS1 were elevated in psychological stress. To more fully characterize human CABS1 we developed additional polyclonal and monoclonal antibodies to different sections of the protein and used these antibodies to characterize CABS1 in an overexpression cell lysate, human salivary glands, saliva, serum and testes using western blot, immunohistochemistry and bioinformatics approaches exploiting the Gene Expression Omnibus (GEO) database. CABS1 appears to have multiple molecular weight forms, consistent with its recognition as a structurally disordered protein, a protein with structural plasticity. Interestingly, in human testes, its cellular distribution differs from that in rodents and pigs, and includes Leydig cells, primary spermatogonia, Sertoli cells and developing spermatocytes and spermatids, Geodata suggests that CABS1 is much more widely distributed than previously recognized, including in the urogenital, gastrointestinal and respiratory tracts, as well as in the nervous system, immune system and other tissues. Much remains to be learned about this intriguing protein.

Structural and posttranslational analysis of human calcium-binding protein, spermatid-associated 1.

Recently, we detected a novel biomarker in human saliva called calcium-binding protein, spermatid-associated 1 (CABS1). CABS1 protein had previously been described only in testis, and little was known of its characteristics other than it was considered a structurally disordered protein. Levels of human CABS1 (hCABS1) in saliva correlate with stress, whereas smaller sized forms of hCABS1 in saliva are associated with resilience to stress. Interestingly, hCABS1 also has an anti-inflammatory peptide sequence near its carboxyl terminus, similar to that of a rat prohormone, submandibular rat 1. We performed phylogenetic and sequence analysis of hCABS1. We found that from 72 CABS1 sequences currently annotated in the National Center for Biotechnology Information protein database, only 14 contain the anti-inflammatory domain "TxIFELL," all of which are primates. We performed structural unfoldability analysis using PONDER and FoldIndex and discovered three domains that are highly disordered. Predictions of three-dimensional structure of hCABS1 using RaptorX, IonCom, and I-TASSER software agreed with these findings. Predicted neutrophil elastase cleavage density also correlated with hCABS1 regions of high structural disorder. Ligand binding prediction identified Ca2+ , Mg2+ , Zn2+ , leucine, and thiamine pyrophosphate, a pattern observed in enzymes associated with energy metabolism and mitochondrial localization. These new observations on hCABS1 raise intriguing questions about the interconnection between the autonomic nervous system, stress, and the immune system. However, the precise molecular mechanisms involved in the complex biology of hCABS1 remain unclear. We provide a detailed in silico analysis of relevant aspects of the structure and function of hCABS1 and postulate extracellular and intracellular roles.

Histologic and histomorphometric evaluation of an allograft stem cell-based matrix sinus augmentation procedure.

PURPOSE: Long-term success of dental implants has been demonstrated when placed simultaneously with or after a sinus augmentation procedure. However, optimal bone formation can be from 6 to 9 months or longer with grafting materials other than autogenous bone. For this reason, there is interest in any surgical technique that does not require autogenous bone harvesting, yet results in sufficient bone formation within a relatively short time frame. MATERIALS AND METHODS: This study evaluated and compared bone formation following sinus-augmentation procedures using either an allograft cellular bone matrix (ACBM), containing native mesenchymal stem cells and osteoprogenitors, or conventional allograft (CA). RESULTS: Histomorphometric analysis of the ACBM grafts revealed average vital bone content of 32.5% ± 6.8% to residual graft content of 4.9% ± 2.4% for the 21 sinuses in the study, at an average healing period of 3.7 ± 0.6 months. Results for the CA, in the same time frame, were average vital bone content of 18.3% ± 10.6% to residual graft content of 25.8% ± 13.4%. A comparison of ACBM and CA grafts, for both vital and residual bone contents, showed P values of .003 and .002, respectively, indicating a statistically significant difference between the groups. CONCLUSION: The high percentage of vital bone content, after a relatively short healing phase, may encourage a more rapid initiation of implant placement or restoration when a cellular grafting approach is considered.

Histologic evaluation of a stem cell-based sinus-augmentation procedure.

BACKGROUND: Predictability has been demonstrated for the long-term success of dental implants placed simultaneously with or after a sinus-augmentation procedure. However, the time required to obtain optimal bone formation can be from 6 to 9 months or longer with grafting materials other than autogenous bone. For this reason, there is interest in a surgical technique that does not require the harvest of autogenous bone but still results in sufficient bone formation within a relatively short time frame. METHODS: The purpose of this case series was to evaluate the bone formation following sinus-augmentation procedures using an allograft cellular bone matrix containing native mesenchymal stem cells. Biopsy and histologic evaluation were performed after approximately 4 months of healing. RESULTS: Histomorphometric analysis revealed an average vital bone content of 33% (range, 22% to 40%) and an average residual graft content of 6% (range, 3% to 7%) for the five cases reported that had an average healing period of 4.1 months (range, 3 to 4.75 months). CONCLUSION: The high percentage of vital bone content, after a relatively short healing phase, may encourage a more rapid initiation of implant placement or restoration when a cellular grafting approach is considered.

Elevation of the maxillary sinus floor with hydraulic pressure.

This study describes a new method using hydraulic pressure to elevate the antral floor for bone grafting between the sinus floor and the schneiderian membrane before placement of endosseous osseointegrated implants. The method was first modeled experimentally in hen eggs, acting as a surrogate sinus, and then in human cadaver preparations. Several clinical case reports are also presented. This technique successfully combines the advantages of the Caldwell-Luc window a pproach, which permits the placement of high bone graft volume, and the simplicity of the osteotome technique by way of the alveolar ridge crest.

A 6-year prospective study of 620 stress-diversion surface (SDS) dental implants.

A 6-year prospective study was conducted to assess the clinical success rates and crestal bone response of a dental implant system with a stress-diversion design. Mathematical modeling, digital radiography with applied isodensity, and finite element analysis were used to highlight the effect of the stress distribution design. A total of 386 hydroxyapatite-coated prototypes and 234 commercial grit-blasted external hex implants were placed in virgin bone as well as various grafted maxillary regions, with 36% of the posterior implants being immediately loaded. Prototypes achieved 96.6% survival over a 3-year period. The grit-blasted implant, placed from 2000 to 2003, showed a 95% survival rate. There were no significant changes in crestal bone levels after the first 12 months of prosthetic loading. Engineering evaluations suggested that undesirable stresses were distributed from the crest of the ridge down through the center of the implant body.

A prospective, multicenter, 4-year study of the ACE Surgical resorbable blast media implant.

This article reports on the 50-month results of the evaluation of the ACE Surgical resorbable blast media (RBM) dental implant. There were 1077 implants placed in 348 patients: 950 in the mandible and 127 in the maxilla. A total of 78.6% of the implants were used to support anterior, mandibular, bar-retained overdentures. The 3.75- to 4.00-mm-diameter implant was used in 91.1% of cases, with the remainder being 3.3 mm (2.2%) or 4.75 mm (6.7%). The implants of 10-, 13-, and 15-mm lengths were used in almost equal amounts in the mandible, maxilla, and anterior or posterior aspects of either jaw. There were 7 failures, all in the mandible and before stage 2 surgery. The overall implant success rate in this 50-month interim report is 99.3% in the mandible and 100% for the maxilla. There was no discernible crestal bone loss during the study period. No differences in bone response were seen in RBM implants with roughened surfaces on the entire implant, up to the collar, or up to the first 2 threads below the collar.

Technique for producing platelet-rich plasma and platelet concentrate: background and process.

Autologous platelet-rich plasma is a source of platelet-derived growth factor (PDGF) and transforming growth factor beta (TGF-beta), both important in accelerating hard and soft tissue maturation. This article describes a two-step centrifugation method to sequester and concentrate platelets to a level four to eight times baseline whole blood values. The technique produces concentrations of PDGF-AB above 500% and TGF-beta1 greater than 800%. Flow cytometry measuring p-selectin expression shows that the platelets remain quiescent throughout the procedure, maintaining their integrity and viability, with no inadvertent activation.