Author Correction: WNT-activated bone grafts repair osteonecrotic lesions in aged animals.

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WNT-activated bone grafts repair osteonecrotic lesions in aged animals.

The Wnt pathway is a new target in bone therapeutic space. WNT proteins are potent stem cell activators and pro-osteogenic agents. Here, we gained insights into the molecular and cellular mechanisms responsible for liposome-reconstituted recombinant human WNT3A protein (L-WNT3A) efficacy to treat osteonecrotic defects. Skeletal injuries were coupled with cryoablation to create non-healing osteonecrotic defects in the diaphysis of the murine long bones. To replicate clinical therapy, osteonecrotic defects were treated with autologous bone graft, which were simulated by using bone graft material from syngeneic ACTB-eGFP-expressing mice. Control osteonecrotic defects received autografts alone; test sites received autografts treated ex vivo with L-WNT3A. In vivo µCT monitored healing over time and immunohistochemistry were used to track the fate of donor cells and assess their capacity to repair osteonecrotic defects according to age and WNT activation status. Collectively, analyses demonstrated that cells from the autograft directly contributed to repair of an osteonecrotic lesion, but this contribution diminished as the age of the donor increased. Pre-treating autografts from aged animals with L-WNT3A restored osteogenic capacity to autografts back to levels observed in autografts from young animals. A WNT therapeutic approach may therefore have utility in the treatment of osteonecrosis, especially in aged patients.

Implanted Dental Pulp Cells Fail to Induce Regeneration in Partial Pulpotomies.

Cell-based partial pulp regeneration is one of the promising approaches to obtain newly formed functional dentin-pulp complex. It relies on the preservation of the healthy tissue while regenerating the damaged pulp. The aim of this study was to investigate whether this regenerative process could be achieved by implanting porcine dental pulp cells (pDPCs) in pulp defects in the minipig. By split-mouth model, self-assembling injectable nanopeptide hydrogel, with and without pDPCs, was implanted after cameral pulpotomy in premolars and molars. At day 21 after surgery, 3-dimensional morphometric characterization, Masson's trichrome staining, and immunolabeling for DSP and BSP (dentin sialoprotein and bone sialoprotein) were performed on treated teeth. This study demonstrated no pulp regeneration but systematic reparative dentinogenesis. In fact, regardless of the presence of pDPCs in the scaffold, an osteodentin bridge-the microarchitecture of which significantly differed from the native dentin-was systematically obtained. Furthermore, the presence of pDPCs significantly affected the microstructure of the dentin bridges. In the radicular area of each treated tooth, hyperemia in the remaining pulp and external root resorptions were observed. Under the conditions tested in this work, pulp regeneration was not achieved, which highlights the need of further investigations to develop favorable regenerative microenvironment.

Relationships among Bone Quality, Implant Osseointegration, and Wnt Signaling.

A variety of clinical classification schemes have been proposed as a means to identify sites in the oral cavity where implant osseointegration is likely to be successful. Most schemes are based on structural characteristics of the bone, for example, the relative proportion of densely compact, homogenous (type I) bone versus more trabeculated, cancellous (type III) bone. None of these schemes, however, consider potential biological characteristics of the bone. Here, we employed multiscale analyses to identify and characterize type I and type III bones in murine jaws. We then combined these analytical tools with in vivo models of osteotomy healing and implant osseointegration to determine if one type of bone healed faster and supported osseointegration better than another. Collectively, these studies revealed a strong positive correlation between bone remodeling rates, mitotic activity, and osteotomy site healing in type III bone and high endogenous Wnt signaling. This positive correlation was strengthened by observations showing that the osteoid matrix that is responsible for implant osseointegration originates from Wnt-responsive cells and their progeny. The potential application of this knowledge to clinical practice is discussed, along with a theory unifying the role that biology and mechanics play in implant osseointegration.

Effects of Condensation on Peri-implant Bone Density and Remodeling.

Bone condensation is thought to densify interfacial bone and thus improve implant primary stability, but scant data substantiate either claim. We developed a murine oral implant model to test these hypotheses. Osteotomies were created in healed maxillary extraction sites 1) by drilling or 2) by drilling followed by stepwise condensation with tapered osteotomes. Condensation increased interfacial bone density, as measured by a significant change in bone volume/total volume and trabecular spacing, but it simultaneously damaged the bone. On postimplant day 1, the condensed bone interface exhibited microfractures and osteoclast activity. Finite element modeling, mechanical testing, and immunohistochemical analyses at multiple time points throughout the osseointegration period demonstrated that condensation caused very high interfacial strains, marginal bone resorption, and no improvement in implant stability. Collectively, these multiscale analyses demonstrate that condensation does not positively contribute to implant stability.

Contribution to interplay between a delamination test and a sensory analysis of mid-range lipsticks.

BACKGROUND: Lipstick is currently one of the most sold products of cosmetics industry, and the competition between the various manufacturers is significant. Customers mainly seek products with high spreadability, especially long-lasting or long wear on the lips. Evaluation tests of cosmetics are usually performed by sensory analysis. This can then represent a considerable cost. OBJECTIVES: The object of this study was to develop a fast and simple test of delamination (objective method with calibrated instruments) and to interplay the obtained results with those of a discriminative sensory analysis (subjective method) in order to show the relevance of the instrumental test. METHODS: Three mid-range lipsticks were randomly chosen and were tested. They were made of compositions as described by the International Nomenclature of Cosmetic Ingredients (INCI). Instrumental characterization was performed by texture profile analysis and by a special delamination test. The sensory analysis was voluntarily conducted with an untrained panel as blind test to confirm or reverse the possible interplay. RESULTS: The two approaches or methods gave the same type of classification. The high-fat lipstick had the worst behaviour with the delamination test and the worst notation of the intensity of descriptors with the sensory analysis. CONCLUSION: There is a high correlation between the sensory analysis and the instrumental measurements in this study. The delamination test carried out should permit to quickly determine the lasting (screening test) and in consequence optimize the basic formula of lipsticks.

Wnt Signaling and Its Contribution to Craniofacial Tissue Homeostasis.

A new field of dental medicine seeks to exploit nature's solution for repairing damaged tissues, through the process of regeneration. Most adult mammalian tissues have limited regenerative capacities, but in lower vertebrates, the molecular machinery for regeneration is an elemental part of their genetic makeup. Accumulating data suggest that the molecular pathways responsible for the regenerative capacity of teleosts, amphibians, and reptiles have fallen into disuse in mammals but that they can be "jumpstarted" by the selective activation of key molecules. The Wnt family of secreted proteins constitutes one such critical pathway: Wnt proteins rank among the most potent and ubiquitous stem cell self-renewing factors, with tremendous potential for promoting human tissue regeneration. Wnt reporter and lineage-tracing strains of mice have been employed to create molecular maps of Wnt responsiveness in the craniofacial tissues, and these patterns of Wnt signaling colocalize with stem/progenitor populations in the rodent incisor apex, the dental pulp, the alveolar bone, the periodontal ligament, the cementum, and oral mucosa. The importance of Wnt signaling in both the maintenance and healing of these craniofacial tissues is summarized, and the therapeutic potential of Wnt-based strategies to accelerate healing through activation of endogenous stem cells is highlighted.

Abnormal osteopontin and matrix extracellular phosphoglycoprotein localization, and odontoblast differentiation, in X-linked hypophosphatemic teeth.

Mutations in phosphate-regulating gene (PHEX) lead to X-linked hypophosphatemic rickets (XLH), a genetic disease characterized by impaired mineralization in bones and teeth. In human XLH tooth dentin, calcospherites that would normally merge as part of the mineralization process are separated by unmineralized interglobular spaces where fragments of matrix proteins accumulate. Here, we immunolocalized osteopontin (OPN) in human XLH teeth, in a three-dimensional XLH human dental pulp stem cell-collagen scaffold culture model and in a rat tooth injury repair model treated with acidic serine- and aspartate-rich motif peptides (ASARM). In parallel, matrix extracellular phosphoglycoprotein (MEPE) immunolocalization and alkaline phosphatase (ALP) activity were assessed in XLH teeth. OPN was expressed by odontoblasts in the XLH models, and localized to the abnormal calcospherites of XLH tooth dentin. In addition, ALP activity and MEPE localization were abnormal in human XLH teeth, with MEPE showing an accumulation in the unmineralized interglobular spaces in dentin. Furthermore, XLH odontoblasts failed to form a well-polarized odontoblast layer. These data suggest that both MEPE and OPN are involved in impaired tooth mineralization associated with XLH, possibly through different effects on the mineralization process.

Assessment of validity and predictability of the FiO2-SpO2 transfer-function in preterm infants.

In this paper an investigation of the gain, delay, and time-constant parameters of the transfer function describing the relation between fraction of inspired oxygen (FiO2) and oxygen saturation in the blood (SpO2) in preterm infants is presented. The parameters were estimated following FiO2 adjustments and goodness of fit was used to assess the validity of the model when using an assumed first-order transfer function. For responses identified to be first-order, the estimated parameters were then clustered to identify areas where they tended to be concentrated. Each group described an operating region of the transfer function; thus, predicting the right operating region could potentially assist a range-based robust inspired oxygen controller to provide more optimal control by adapting itself to different clusters. Accordingly, the samples were assigned labels based on their cluster associations and 14 features available at the time of each adjustment were used as inputs to an artificial neural network to classify the clustered samples. The validity study suggested that 37% of the adjustments were followed by first-order responses. Prediction studies on the first-order responses indicated that the clusters could be predicted with an average accuracy of 64% when the parameters were divided into two groups.

[Odontogenic keratocyst related to a Gorlin syndrome: a case report]. / Kératokystes odontogènes dans le cadre d'un syndrome de Gorlin: à propos d'un cas clinique.

We are reporting here, the case of a 9 years old boy with Gorlin syndrome diagnosis. Current knowledge on this syndrome is reviewed.

Effectiveness of intensive insulin therapy by multiple daily injections and continuous subcutaneous infusion: a comparison study in type 2 diabetes with conventional insulin regimen failure.

OBJECTIVE: To compare the effectiveness of two intensified insulin regimens, i.e., pump delivery versus multiple daily injections in patients with type 2 diabetes not optimally controlled with conventional insulin therapy. RESEARCH DESIGN AND METHODS: Seventeen type 2 diabetes patients uncontrolled by two daily injections of regular plus NPH were randomly assigned in a cross-over fashion to either three daily injections of lispro plus NPH or pump device delivering lispro. HbA1c, 6 points capillary blood glucose, 24-hour continuous glucose monitoring system tracings and global satisfaction score were evaluated at the end of each 12-week treatment period. RESULTS: HbA1c decreased from 9.0+/-1.6% to 8.6+/-1.6% with multiple injections and 7.7+/-0.8% with pump device (p<0.03). Capillary blood glucose was lowered at all time-points with pump, but only at morning with multiple injections (p<0.01). Compared to conventional therapy, pump reduced hyperglycemic area under curve by 73% (p<0.01), but multiple injections by only 32% (p=0.08). Rate of hypoglycemia was not increased and patient's satisfaction was comparable with both intensive treatments. CONCLUSIONS: Pump therapy provides a better metabolic control than injection regimens, and seems to be safe and convenient in patients with type 2 diabetes who fail to respond to conventional insulin therapy.

Prostatic neuroendocrine tumor in multiple endocrine neoplasia Type 2B.

We report the unusual occurrence of a neuroendocrine prostatic tumor in two young males with multiple endocrine neoplasia (MEN) 2B. Immunohistochemistry of the tumor markers may help differentiate a primary neuroendocrine prostate tumor from the metastasis of a medullary thyroid carcinoma of poor prognosis. MEN 2B hallmarks (i.e. plasma thyrocalcitonin and urinary metanephrines) may be systematically investigated in neuroendocrine tumors of the prostate, and conversely prostate examination may be performed in the periodic screening of MEN 2B male patients.

Linkage analysis of candidate regions using a composite neurocognitive phenotype correlated with schizophrenia.

As schizophrenia is genetically and clinically heterogeneous, systematic investigations are required to determine whether ICD-10 or DSM-IV categorical diagnoses identify a phenotype suitable and sufficient for genetic research, or whether correlated phenotypes incorporating neurocognitive performance and personality traits provide a phenotypic characterisation that accounts better for the underlying variation. We utilised a grade of membership (GoM) model (a mathematical typology developed for studies of complex biological systems) to integrate multiple cognitive and personality measurements into a limited number of composite graded traits (latent pure types) in a sample of 61 nuclear families comprising 80 subjects with ICD-10/DSM-IV schizophrenia or schizophrenia spectrum disorders and 138 nonpsychotic first-degree relatives. GoM probability scores, computed for all subjects, allowed individuals to be partly assigned to more than one pure type. Two distinct and contrasting neurocognitive phenotypes, one familial, associated with paranoid schizophrenia, and one sporadic, associated with nonparanoid schizophrenia, accounted for 74% of the affected subjects. Combining clinical diagnosis with GoM scores to stratify the entire sample into liability classes, and using variance component analysis (SOLAR), in addition to parametric and nonparametric multipoint linkage analysis, we explored candidate regions on chromosomes 6, 10 and 22. The results indicated suggestive linkage for the familial neurocognitive phenotype (multipoint MLS 2.6 under a low-penetrance model and MLS>3.0 under a high-penetrance model) to a 14 cM area on chromosome 6, including the entire HLA region. Results for chromosomes 10 and 22 were negative. The findings suggest that the familial neurocognitive phenotype may be a pleiotropic expression of genes underlying the susceptibility to paranoid schizophrenia. We conclude that use of composite neurocognitive and personality trait measurements as correlated phenotypes supplementing clinical diagnosis can help stratify the liability to schizophrenia across all members of families prior to linkage, allow the search for susceptibility genes to focus selectively on subsets of families at high genetic risk, and augment considerably the power of genetic analysis.

Pseudotumor cerebri associated with Sjögren's syndrome.

PURPOSE: To report a case of papilledema and pseudotumor cerebri developed in association with Sjögren's syndrome. METHODS: Case-report of a 38-year-old woman with history, imaging and histology confirming the diagnosis of both pseudotumor cerebri and Sjögren's syndrome who presented with bilateral decrease of vision. RESULTS: Papilledema associated with pseudotumor cerebri was observed in both eyes. The patient's visual acuity improved transiently with the administration of intravenous steroids and cyclophosphamide; subsequently she needed a ventriculoperitoneal shunt. CONCLUSION: Sjögren's syndrome should be considered in the different etiologies of pseudotumor cerebri. The major improvement with corticosteroids and ventriculoperitoneal shunt makes prompt diagnosis essential.

Relationship between polymorphisms in the renin-angiotensin system and nephropathy in type 2 diabetic patients.

BACKGROUND: Renin Angiotensin system is involved in renal function and its polymorphisms may influence diabetic nephropathy. ID ACE polymorphism modulates ACE level whereas M235T AGT polymorphism is involved in arterial hypertension. The A1166C AT1R polymorphism is involved in arterial hypertension and in diabetic retinopathy. METHODS: Two hundred thirty five type 2 diabetic patients were enrolled in this transversal study. Data were documented for clinical characteristics of the population, HbA(1c), urinary albumin excretion, presence of retinopathy or antihypertensive treatment. Polymorphisms were analyzed by PCR techniques. The patients were divided into 3 groups: group 1, without nephropathy (n=118), group 2, microalbuminuria (n=78), group 3, macroalbuminuria (n=39). RESULTS: Diabetes duration was longer (p<0.001), retinopathy (p<0.001) and antihypertensive treatment (p<0.02) were more frequent in group 3 compared to group 1 and 2. The I/D ACE and M235T AGT polymorphisms were not differently distributed between the three groups. In contrast, the CC genotype of the AT1R polymorphism was overrepresented in group 2 (p=0.021). The presence of the CC AT1R genotype considerably increased the incidence of albuminuria after 10 years of diabetes (AA vs CC p=0.01), particurlarly in men. No effect was seen with I/D ACE and M235T AGT polymorphisms. CONCLUSION: In conclusion, we observed an interaction of A1166C AT1R polymorphism with diabetes in men but not of I/D ACE and M235T AGT polymorphisms.

Differences between men and women in compliance with risk factor reduction: before and after coronary artery bypass surgery.

The purpose of this study was to determine whether a difference exists between genders in compliance to a heart-healthy lifestyle and whether the stress of coronary artery bypass graft (CABG) surgery caused one of the genders to become more compliant. A convenience sample of 30 men and 30 women who had CABG surgery at least 1 year earlier and were enrolled in a follow-up program through a cardiovascular surgeon's office were interviewed to assess coronary artery disease risk. The instrument used was the RISKO Heart Hazard Appraisal Tool. Preoperative records were also reviewed with the same tool to assess a person's preoperative risk. The research design used was 2 x 2 repeated measures. Data were analyzed with 2 x 2 repeated measures analysis of variance (ANOVA). Two findings were discovered. First, a statistically significant difference exists between men and women (F = 5.82 P =.019), with men scoring lower RISKO scores than women, indicating lower cardiovascular risk and better compliance to a healthy lifestyle, both before and after surgery. Second, a significant difference exists between preoperative and postoperative RISKO scores in the total population (F = 8.77 P =.004). Postoperative RISKO scores were lower, indicating an improvement in cardiovascular risk. The risk factors assessed are applicable to both heart disease and peripheral vascular disease.

Juxtafacet cyst of the lumbar spine. Clinical, radiological and therapeutic aspects in 28 cases.

OBJECT: A consecutive series of 28 "operated" juxtafacet cysts is reported. We emphasize the clinical and radiological aspects leading to diagnosis. We also discuss the results of the surgical treatment. MATERIAL AND METHODS: Medical information and radiological studies involving 28 patients were analyzed. Each patient has been operated on by decompressive laminectomy and resection of the cyst. The diagnosis was always confirmed by a pathological examination. The cyst most frequently occurred at the L4-L5 level (n = 18), and seldom at the L5-S1 (n - 6) or L3-L4 (n - 4) levels. RESULTS: The differential diagnosis from other pathological causes responsible for a radicular compression could not be done by physical examination. Spine X-rays or myelogram were nonspecific. Computed Tomography or CT-myelography could help in the diagnosis but MR imaging was the most sensitive. In our series, the respective sensitivities of these techniques are 56, 42 and 77%. The preoperative diagnosis was correct in 18 patients (64%). The cyst was sometimes adherent to the underlying dura, then significantly increasing the risk of dural tear and spinal fluid leak, especially when located at L3-L4 level. Surgical ablation lead to a complete recovery or an important improvement in 26 patients. CONCLUSIONS: The diagnosis of the juxtafacet cyst of the lumbar spine is better achieved by MRI. Surgery is the gold standard treatment, safe and long-term effective. When a total cyst removal with an internal facetectomy are performed, recurrence is exceptional.

Herpes simplex virus DNA packaging sequences adopt novel structures that are specifically recognized by a component of the cleavage and packaging machinery.

The product of the herpes simplex virus type 1 U(L)28 gene is essential for cleavage of concatemeric viral DNA into genome-length units and packaging of this DNA into viral procapsids. To address the role of U(L)28 in this process, purified U(L)28 protein was assayed for the ability to recognize conserved herpesvirus DNA packaging sequences. We report that DNA fragments containing the pac1 DNA packaging motif can be induced by heat treatment to adopt novel DNA conformations that migrate faster than the corresponding duplex in nondenaturing gels. Surprisingly, these novel DNA structures are high-affinity substrates for U(L)28 protein binding, whereas double-stranded DNA of identical sequence composition is not recognized by U(L)28 protein. We demonstrate that only one strand of the pac1 motif is responsible for the formation of novel DNA structures that are bound tightly and specifically by U(L)28 protein. To determine the relevance of the observed U(L)28 protein-pac1 interaction to the cleavage and packaging process, we have analyzed the binding affinity of U(L)28 protein for pac1 mutants previously shown to be deficient in cleavage and packaging in vivo. Each of the pac1 mutants exhibited a decrease in DNA binding by U(L)28 protein that correlated directly with the reported reduction in cleavage and packaging efficiency, thereby supporting a role for the U(L)28 protein-pac1 interaction in vivo. These data therefore suggest that the formation of novel DNA structures by the pac1 motif confers added specificity on recognition of DNA packaging sequences by the U(L)28-encoded component of the herpesvirus cleavage and packaging machinery.

Malaria parasite exit from the host erythrocyte: a two-step process requiring extraerythrocytic proteolysis.

Intraerythrocytic malaria parasites replicate by the process of schizogeny, during which time they copy their genetic material and package it into infective merozoites. These merozoites must then exit the host cell to invade new erythrocytes. To better characterize the events of merozoite escape, erythrocytes containing Plasmodium falciparum schizonts were cultured in the presence of the cysteine protease inhibitor, l-transepoxy-succinyl-leucylamido-(4-guanidino)butane (E64). This treatment resulted in the accumulation of extraerythrocytic merozoites locked within a thin, transparent membrane. Immunomicroscopy demonstrated that the single membrane surrounding the merozoites is not erythrocytic but rather is derived from the parasitophorous vacuolar membrane (PVM). Importantly, structures identical in appearance can be detected in untreated cultures at low frequency. Further studies revealed that (i) merozoites from the PVM-enclosed merozoite structures (PEMS) are invasive, viable, and capable of normal development; (ii) PEMS can be purified easily and efficiently; and (iii) when PEMS are added to uninfected red blood cells, released merozoites can establish a synchronous wave of infection. These observations suggest that l-transepoxy-succinyl-leucylamido-(4-guanidino)butane (E64) causes an accumulation of an intermediate normally present during the process of rupture. We propose a model for the process of rupture: merozoites enclosed within the PVM first exit from the host erythrocyte and then rapidly escape from the PVM by a proteolysis-dependent mechanism.

Proteolytic cleavage of the amino terminus of the U(L)15 gene product of herpes simplex virus type 1 is coupled with maturation of viral DNA into unit-length genomes.

The U(L)15 gene of herpes simplex virus type 1 (HSV-1), like U(L)6, U(L)17, U(L)28, U(L)32, and U(L)33, is required for cleavage of concatameric DNA into genomic lengths and for packaging of cleaved genomes into preformed capsids. A previous study indicated that the U(L)15 gene encodes minor capsid proteins. In the present study, we have shown that the amino-terminal 509 amino acids of the U(L)15-encoded protein are sufficient to confer capsid association inasmuch as a carboxyl-terminally truncated form of the U(L)15-encoded protein with an M(r) of approximately 55,000 readily associated with capsids. This and previous studies have shown that, whereas three U(L)15-encoded proteins with apparent M(r)s of 83,000, 80,000, and 79,000 associated with wild-type B capsids, only the full-length 83,000-M(r) protein associated with B capsids purified from cells infected with viruses lacking functional U(L)6, U(L)17, U(L)28, U(L)32, and U(L)33 genes (B. Salmon and J. D. Baines, J. Virol. 72:3045-3050, 1998). Thus, all viral mutants that fail to cleave viral DNA into genomic-length molecules also fail to produce capsid-associated U(L)15 80,000- and 79,000-M(r) proteins. In contrast, the 80,000- and 79,000-M(r) proteins were readily detected in capsids purified from cells infected with a U(L)25 null virus that cleaves, but does not package, DNA. The conclusion that the amino terminus of the 83,000-M(r) protein is truncated to produce the 80,000- and/or 79,000-M(r) protein was supported by the following observations. (i) Whereas the C termini of the 83,000-, 80, 000-, and 79,000-M(r) proteins are identical, immunoreactivity dependent on the first 35 amino acids of the U(L)15 83,000-M(r) protein was absent from the 80,000- and 79,000-M(r) proteins. (ii) The 79,000- and 80,000-M(r) proteins were detected in capsids from cells infected with HSV-1(U(L)15M36V), an engineered virus encoding valine rather than methionine at codon 36. Thus, initiation at codon 36 is unlikely to account for production of the 80,000- and/or 79, 000-M(r) protein. Taken together, these data strongly suggest that capsid-associated U(L)15-encoded protein is proteolytically cleaved near the N terminus and indicate that this modification is tightly linked to maturation of genomic DNA.