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1.
Environ Sci Technol ; 57(16): 6540-6549, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37067383

RESUMO

Groundwater discharge into the sea occurs along many coastlines around the world in different geological settings and constitutes an important component of global water and matter budget. Estimates of how much water flows into the sea worldwide vary widely and are largely based on onshore studies and hydrological or hydrogeological modeling. In this study, we propose an approach to quantify a deep submarine groundwater outflow from the seafloor by using autonomously measured ocean surface data, i.e., 222Rn as groundwater tracer, in combination with numerical modeling of plume transport. The model and field data suggest that groundwater outflows from a water depth of ∼100 m can reach the sea surface implying that several cubic meters per second of freshwater are discharged into the sea. We postulate an extreme rainfall event 6 months earlier as the likely trigger for the groundwater discharge. This study shows that measurements at the sea surface, which are much easier to conduct than discharge measurements at the seafloor, can be used not only to localize submarine groundwater discharges but, in combination with plume modeling, also to estimate the magnitude of the release flow rate.


Assuntos
Água Subterrânea , Radônio , Radônio/análise , Água do Mar , Movimentos da Água , Água , Oceanos e Mares , Monitoramento Ambiental
2.
Can J Surg ; 66(2): E103-E108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36882202

RESUMO

BACKGROUND: The constrained posterior-stabilized (CPS) implant for use in total knee arthroplasty (TKA) has a constraint level midway between that of a posterior-stabilized implant and a valgus-varus-constrained implant; there is currently no consensus on the surgical indications for use of this degree of constraint. We present our experience using this implant at our centre. METHODS: We reviewed the charts of patients who received a CPS polyethylene insert during TKA in our centre between January 2016 and April 2020. We collected patient demographic characteristics, surgical indications, pre- and postoperative radiographs, and complications. RESULTS: A total of 85 patients (74 females and 11 males with a mean age of 73 yr [standard deviation 9.4 yr, range 36-88 yr]) (85 knees) received a CPS insert over the study period. Of the 85 cases, 80 (94%) were primary TKA and 5 (6%) were revision TKA. The most common indications for primary CPS use were severe valgus deformity with medial soft-tissue laxity (29 patients [34%]), medial soft-tissue laxity without substantial deformity (27 [32%]) and severe varus deformity with lateral soft-tissue laxity (13 [15%]). The indications for the 5 patients who underwent revision TKA were medial laxity (4 patients) and an iatrogenic lateral condyle fracture (1 patient). Four patients had postoperative complications. The 30-day return to hospital rate was 2.3% (owing to infection and hematoma). A single patient required revision surgery for periprosthetic joint infection. CONCLUSION: We found excellent short-term survivorship of the CPS polyethylene insert when used for a spectrum of coronal plane ligamentous imbalances with or without pre-operative coronal plane deformities. Long-term follow-up of these cases will be important to identify adverse outcomes such as loosening or polyethylene-related problems.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Feminino , Masculino , Humanos , Idoso , Reoperação , Artroplastia do Joelho/efeitos adversos , Prótese do Joelho/efeitos adversos , Polietileno , Medição de Risco
3.
Hum Genet ; 139(11): 1429-1441, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32488467

RESUMO

Autozygosity-driven exome analysis has been shown effective for identification of genes underlying recessive diseases especially in countries of the so-called Greater Middle East (GME), where high consanguinity unravels the phenotypic effects of recessive alleles and large family sizes facilitate homozygosity mapping. In Italy, as in most European countries, consanguinity is estimated low. Nonetheless, consanguineous Italian families are not uncommon in publications of genetic findings and are often key to new associations of genes with rare diseases. We collected 52 patients from 47 consanguineous families with suspected recessive diseases, 29 originated in GME countries and 18 of Italian descent. We performed autozygosity-driven exome analysis by detecting long runs of homozygosity (ROHs > 1.5 Mb) and by prioritizing candidate clinical variants within. We identified a pathogenic synonymous variant that had been previously missed in NARS2 and we increased an initial high diagnostic rate (47%) to 55% by matchmaking our candidate genes and including in the analysis shorter ROHs that may also happen to be autozygous. GME and Italian families contributed to diagnostic yield comparably. We found no significant difference either in the extension of the autozygous genome, or in the distribution of candidate clinical variants between GME and Italian families, while we showed that the average autozygous genome was larger and the mean number of candidate clinical variants was significantly higher (p = 0.003) in mutation-positive than in mutation-negative individuals, suggesting that these features influence the likelihood that the disease is autozygosity-related. We highlight the utility of autozygosity-driven genomic analysis also in countries and/or communities, where consanguinity is not widespread cultural tradition.


Assuntos
Testes Genéticos/métodos , Genoma Humano/genética , Mapeamento Cromossômico/métodos , Consanguinidade , Exoma/genética , Família , Feminino , Genes Recessivos/genética , Humanos , Itália , Masculino , Oriente Médio , Mutação/genética , Linhagem
4.
Odontology ; 104(2): 199-210, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26156449

RESUMO

Guided bone regeneration (GBR) procedures using graft materials have been used for reconstruction of osseous defects. The aim of the present in vivo micro-computed tomographic (µCT) and histologic study was to assess in real time the bone regeneration at GBR sites in standardized experimental calvarial defects (diameter 3.3 mm) using ß-tricalcium phosphate (ß-TCP) with and without collagen membrane (CM). A single full-thickness calvarial defect was created on the left parietal bone in young female Wistar albino rats (n = 30) weighing approximately 300 g and aged about 6 weeks. The animals were randomly divided into three groups for treatment, based on calvarial defect filling material: (1) control group (n = 10); (2) ß-TCP + CM group (n = 10); (3) ß-TCP group (n = 10). Real-time in vivo µCT analyses were performed immediately after surgery and at 2, 4, 6 and 10 weeks to determine the volume and mineral density of the newly formed bone (BVNFB, MDNFB) and remaining ß-TCP particles (VRBP, MDRBP). The animals were killed at 10 weeks and calvarial specimens were evaluated histologically. In the control group, MDNFB increased significantly at 6 weeks (0.32 ± 0.002 g/mm(3), P < 0.01) compared to that at baseline. In ß-TCP + CM group, BVNFB (1.10 ± 0.12 mm(3), P < 0.01) and MDNFB (0.13 ± 0.02 g/mm(3), P < 0.01) significantly increased at the 4th week than baseline. In the ß-TCP group, BVNFB (1.13 ± 0.12 mm(3), P < 0.01) and MDNFB (0.14 ± 0.01 g/mm(3), P < 0.01) significantly increased at 6 weeks compared to that at baseline. Significant reduction in VRBP was neither seen in the ß-TCP + CM group nor in the ß-TCP group. While in the ß-TCP + CM group MDRBP was reduced significantly at 6 weeks (0.44 ± 0.9 g/mm(3), P < 0.01) from baseline (0.98 ± 0.03 g/mm(3)), similar significant reduction in MDRBP from baseline (0.92 ± 0.07 g/mm(3)) was seen only at 10 weeks (0.45 ± 0.06 g/mm(3), P < 0.05) in the ß-TCP group. Histologic findings at 10 weeks revealed greater amount of NFB with osteocytes in the matrix, in the ß-TCP + CM group than in the ß-TCP group. Biomechanical assessment of NFB for hardness (H) and elastic modulus (E) revealed significantly higher values for the ß-TCP + CM group (H = 612.6 ± 4.28 Mpa; E = 13.57 ± 0.07 Gpa) when compared to those of the control (H = 192.1 ± 4.93 Mpa; E = 6.76 ± 0.04 Gpa) and the ß-TCP groups (H = 241.9 ± 6.29 Mpa; E = 4.34 ± 0.06 Gpa). In conclusion, based on real-time assessment, NFB is formed in calvarial defects as early as 4 weeks following GBR with ß-TCP + CM as compared to 6 weeks when ß-TCP alone was used.


Assuntos
Regeneração Óssea , Fosfatos de Cálcio/uso terapêutico , Colágeno/uso terapêutico , Animais , Feminino , Osteogênese , Distribuição Aleatória , Ratos , Ratos Wistar , Crânio/patologia
5.
Anim Genet ; 44(3): 336-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22957920

RESUMO

Among all livestock species, cattle have a prominent status as they have contributed greatly to the economy, nutrition and culture from the beginning of farming societies until the present time. The origins and diversity of local cattle breeds have been widely assessed. However, there are still some regions for which very little of their local genetic resources is known. The present work aimed to estimate the genetic diversity and the origins of Omani cattle. Located in the south-eastern corner of the Arabian Peninsula, close to the Near East, East Africa and the Indian subcontinent, the Sultanate of Oman occupies a key position, which may enable understanding cattle dispersal around the Indian Ocean. To disclose the origin of this cattle population, we used a set of 11 polymorphic microsatellites and 113 samples representing the European, African and Indian ancestry to compare with cattle from Oman. This study found a very heterogenic population with a markedly Bos indicus ancestry and with some degree of admixture with Bos taurus of African and Near East origin.


Assuntos
Bovinos/genética , Variação Genética , África Oriental , Alelos , Animais , Cruzamento , Bovinos/classificação , Loci Gênicos , Oceano Índico , Repetições de Microssatélites , Oriente Médio , Omã , Filogenia , Filogeografia
6.
Med Princ Pract ; 22(5): 438-43, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23689228

RESUMO

OBJECTIVE: To determine the molecular basis of familial ichthyosis in three Omani families. SUBJECTS AND METHODS: Nine patients from three consanguineous families, A, B, and C, were born with typical features of lamellar ichthyosis subtype including collodion membrane and maintained ectropion, and epidermal scaling through their childhood. The 4 patients from family B had more severe symptoms requiring neonatal critical care and subsequent regular treatment with emollients, eye lubricants, and low-dose acitretin. DNA was extracted from peripheral blood by standard methods. The samples were initially genotyped to screen known loci linked to recessive ichthyosis on chromosomes 2q33-32 (ABCA12), 14q11 (TGM1), and 19p12-q12 using commercially supplied polymorphic fluorescent microsatellite markers. TGM1 was analyzed by direct sequencing for disease-associated mutations. RESULTS: Two known pathogenic mutations in TGM1 were detected: p.Gly278Arg in families A and B and p.Arg396His in family C. These two mutations were segregating in an autosomal recessive mode of inheritance. CONCLUSION: Two known pathogenic TGM1 mutations were detected in three large consanguineous Omani families with lamellar ichthyosis. This study confirmed the geographic distribution of known mutations to an apparently unrelated population.


Assuntos
Consanguinidade , Ictiose Lamelar/genética , Transglutaminases/genética , Haplótipos , Humanos , Repetições de Microssatélites , Mutação , Omã/epidemiologia , Análise de Sequência de DNA , Índice de Gravidade de Doença
7.
Cell Physiol Biochem ; 29(1-2): 163-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22415085

RESUMO

Inhaled ultrafine (nano) particles can translocate into the bloodstream and interact with circulatory cells causing systemic and cardiovascular events. To gain more insight into this potential mechanism, we studied the interaction of diesel exhaust particles (DEP) with human, rat and mouse erythrocytes in vitro. Incubation of erythrocytes with DEP (1, 10 or 100 µg/ml) for 30 min caused the highest hemolytic effect (up to 38%) in rats, compared to small but significant hemolysis in mice (up to 2.5%) and humans (up to 0.7%). Transmission electron microscopy of erythrocytes revealed the presence of variable degrees of ultrafine (nano)-sized aggregates of DEP either internalized and/or adsorbed onto the erythrocytes in the three species. A significant amount of DEP was found in rat and mouse (but not human) erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes of rats, but not humans or mice. Unlike in human erythrocytes, total antioxidant status (TAS) and superoxide dismutase (SOD) activity in rats were significantly and dose- dependently decreased. In mouse erythrocytes, DEP caused a decreased in SOD (at 10 µg/ml) and TAS (at 100 µg/ml) activities. In conclusion, DEP caused species-dependent erythrocyte hemolysis and oxidative stress, and were either taken up and/or adsorbed onto the red blood cells. Rat (and to a lesser degree mouse) erythrocytes were susceptible to DEP. Human erythrocytes showed the highest resistance to the observed effects. These species difference should be noted when using rats and mice blood as models for humans.


Assuntos
Eritrócitos/efeitos dos fármacos , Emissões de Veículos/toxicidade , Adulto , Animais , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Masculino , Malondialdeído/metabolismo , Camundongos , Microscopia Confocal , Pessoa de Meia-Idade , Nanopartículas/química , Nanopartículas/toxicidade , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
9.
Saudi Dent J ; 33(8): 1119-1125, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34938057

RESUMO

OBJECTIVE: The research was designed to assess silica calcium phosphate nanocomposite (SCPC) biocompatibility and bioactivity as an osteoinductive scaffold and cell carrier. Consequently, the ability of cell seeded SCPC implant to regenerate a critical size defect in rat calvarium. MATERIALS AND METHODS: The study was conducted in two parts. A series of in vitro experiments on bone marrow stromal cells (MSCs) seeded in the SCPC scaffold evaluated cell attachment, proliferation and osteogenic differentiation. In the second part, a cell seeded SCPC construct was implanted in rat calvarium and bone regeneration was assessed by histological examination to evaluate the newly formed bone quality and the residual graft volume. RESULTS: In vitro experimentation revealed that MSCs cultured on SCPC maintained viability and proliferation when seeded into the SCPC. Scanning electron microscopy demonstrated cell adhesion and calcium appetite formation, MSCs differentiated towards the osteogenic lineage as indicated by the upregulation of RUNX2, ALP, Col1a1 markers. Histological examination showed regeneration from the periphery and core of the defect with new bone formation at different stages of maturation. CONCLUSION: Regenerative medicine delivers promising solutions and technologies for application in craniofacial reconstruction. SCPC scaffold has the potential to be used as a cell carrier to achieve stem cell-based bone regeneration, which provides a viable alternative for treatment of challenging critical size defect.

10.
Saudi Dent J ; 33(5): 248-255, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34194187

RESUMO

BACKGROUND: The morbidities and complications reported in the reconstruction of large bony defects have inspired progression in the field of bioengineering, with a recent breakthrough for the use of decellularized skeletal muscle grafts (DSMG). AIM: To assess the osteogenic potentials of seeded DSMG in vitro and to investigate bone regeneration in critical size defect in vivo. MATERIALS AND METHODS: Assessment of cell viability and characterization was carried out on seeded DSMG for different intervals in vitro. For in vivo experiments, histological analysis was performed for rat cranial defects for the following groups: (A) non-treated DSMG and (B) seeded DSMG after a period of 8 weeks. RESULTS: The in vitro experiment demonstrated the lack of cytotoxicity and inert properties of seeded DSMG; these facilitated the osteogenic differentiation and significant gene expressions, particularly of COL1A1, RUNX2, and OPN (1.9174 ± 0.11673, 1.1806 ± 0.02383, and 1.1802 ± 0.00775, respectively). In the in vivo experiment, superior results were detected in the seeded DSMG group which showed highly vascularized and cellular dense connective tissue with deposited bone matrix and multiple scattered islets of newly formed bone. CONCLUSION: Our results demonstrated the promising aspects of DSMG; however, there is a lack of studies to support further implications.

11.
Oman Med J ; 35(3): e141, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32704389

RESUMO

OBJECTIVES: We sought to describe the clinical and genetic characteristics of patients with familial hypercholesterolemia (FH) that presented to the lipid clinic at Sultan Qaboos University Hospital, Muscat, Oman. METHODS: Patients who presented with high low-density lipoprotein cholesterol (LDL-C) levels (> 189.0 mg/dL or 4.9 mmol/L) were recruited to the study. FH was diagnosed according to the Dutch Lipid Clinic Network criteria. Analyses were performed using univariate statistics. RESULTS: The study enrolled 450 patients with a mean age of 48.0±12.0 years, 56.0% (n = 252) were males and 11.3% (n = 51) were smokers. At admission, the proportion of 'probable/definite', 'possible', and 'unlikely' FH were 27.6% (n = 124), 70.0% (n = 315), and 2.4% (n = 11), respectively. Overall, 26.0% (n = 117) of patients had hypertension, 22.4% (n = 101) had a history of coronary artery disease, and 17.3% (n = 78) had diabetes mellitus. Those with 'probable/definite' FH were more likely to be prescribed high-intensity statin therapy (75.8% vs. 54.5%; p < 0.001) and statin ezetimibe combination (50.8% vs. 27.3%; p < 0.001) when compared to the 'unlikely' FH cohort. Additionally, those with very high atherosclerotic vascular disease (ASCVD) risk were also associated with high-intensity statin therapy (54.7% vs. 42.7%; p = 0.006) and statin ezetimibe combination (26.4% vs. 17.2%; p = 0.023). Patients with 'probable/definite' FH were less likely to achieve their LDL-C goal attainment compared to those with 'unlikely' FH (13.0% vs. 57.1%; p < 0.001). Furthermore, those with very high ASCVD risk were less likely to achieve their LDL-C goals compared to the high ASCVD risk cohort (9.6% vs. 32.0%; p < 0.001). CONCLUSIONS: FH patients are underdiagnosed, undertreated, and less likely to attain their LDL-C goals in Oman.

12.
J Genet Eng Biotechnol ; 18(1): 8, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32115674

RESUMO

BACKGROUND: Hereditary hearing loss is a heterogeneous group of complex disorders with an overall incidence of one in every 500 newborns presented as syndromic and non-syndromic forms. Cadherin-related 23 (CDH23) is one of the listed deafness causative genes. It is found to be expressed in the stereocilia of hair cells and in the retina photoreceptor cells. Defective CDH23 have been associated mostly with prelingual severe-to-profound sensorineural hearing loss (SNHL) in either syndromic (USH1D) or non-syndromic SNHL (DFNB12) deafness. The purpose of this study was to identify causative mutations in an Omani family diagnosed with severe-profound sensorineural hearing loss by whole exome sequencing technique and analyzing the detected variant in silico for pathogenicity using several in silico mutation prediction software. RESULTS: A novel homozygous missense variant, c.A7436C (p. D2479A), in exon 53 of CDH23 was detected in the family while the control samples were all negative for the detected variant. In silico mutation prediction analysis showed the novel substituted D2479A to be deleterious and protein destabilizing mutation at a conserved site on CDH23 protein. CONCLUSION: In silico mutation prediction analysis might be used as a useful molecular diagnostic tool benefiting both genetic counseling and mutation verification. The aspartic acid 2479 alanine missense substitution might be the main disease-causing mutation that damages CDH23 function and could be used as a genetic hearing loss marker for this particular Omani family.

13.
HGG Adv ; 1(1): 100009, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-35047831

RESUMO

Individuals with orofacial asymmetry due to mucosal overgrowths, ipsilateral bone and dental aberrations with perineurial hyperplasia and/or perineuriomatous pseudo-onion bulb proliferations, comprise a recognizable clinical entity. In this article, we describe three individuals with this clinical entity and mosaic PIK3CA variants c.3140A>G (p. His1047Arg), c.328_330delGAA (p. Glu110del), and c.1353_1364del (p.Glu453_Leu456del). We conclude that the identification of these mosaic variants in individuals with orofacial asymmetry presenting histopathologically perineurial hyperplasia and/or intraneural pseudo-onion bulb perineurial cell proliferations supports the inclusion of this clinical entity in the PIK3CA-related overgrowth spectrum.

14.
ACS Appl Mater Interfaces ; 11(36): 33435-33441, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31425649

RESUMO

Despite intensive study over many years, the chemistry and physics of the atomic level mechanisms that govern corrosion are not fully understood. In particular, the occurrence and severity of highly localized metal degradation cannot currently be predicted and often cannot be rationalized in failure analysis. We report a first-principles model of the nature of protective iron carbonate films coupled with a detailed chemical and physical characterization of such a film in a carefully controlled environment. The fundamental building blocks of the protective film, siderite (FeCO3) crystallites, are found to be very sensitive to the growth environment. In iron-rich conditions, cylindrical crystallites form that are highly likely to be more susceptible to chemical attack and dissolution than the rhombohedral crystallites formed in iron-poor conditions. This suggests that local degradation of metal surfaces is influenced by structures that form during early growth and provides new avenues for the prevention, detection, and mitigation of carbon steel corrosion.

15.
Eur J Med Genet ; 62(12): 103592, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30476627

RESUMO

Hearing loss is a debilitating disorder that impairs language acquisition, resulting in disability in children and potential isolation in adulthood. Its onset can have a genetic basis, though environmental factors, which are often preventable, can also cause the condition. The genetic forms are highly heterogeneous, and early detection is necessary to arrange appropriate patient support. Here we report the molecular basis of hereditary hearing loss in a consanguineous family with multiple affected members from Oman. Combining homozygosity mapping with whole exome sequencing identified a novel homozygous nucleotide substitution c.575T > C in the lipoma HMGIC fusion partner-like 5 gene (LHFPL5), that converted the 192nd amino acid residue in the protein from a leucine to a proline, p.(Leu192Pro). Sanger sequencing confirmed segregation with the disease phenotype as expected for a recessive condition and the variant was absent in 123,490 subjects from various disease-specific and population genetic studies as well as 150 unrelated individuals and 35 deaf patients of Omani ethnicity. This study, which describes a novel LHFPL5 mutation in a family of Omani origin with hereditary hearing loss, supports previous clinical descriptions of the condition and contributes to the genetic spectrum of mutations in this form of deafness.


Assuntos
Surdez/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Criança , Pré-Escolar , Surdez/patologia , Homozigoto , Humanos , Masculino , Irmãos
16.
Front Physiol ; 8: 158, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28420996

RESUMO

There is a global increase in the popularity of water-pipe tobacco smoking including in Europe and North America. Nevertheless, little is known about the male reproductive effects of water-pipe smoke (WPS), especially after long-term exposure. Here, we assessed effects of WPS exposure (30 min/day) in male mice for 6 months. Control mice were exposed to air-only for the same period of time. Twenty-four hours after the last exposure, testicular histopathology, and markers of inflammation and oxidative stress, and the tyrosine-protein kinase vascular endothelial growth factor receptor 1 (VEGFR1) were assessed in testicular homogenates. Moreover, plasma testosterone, estradiol, and luteinizing hormone (LH) concentrations were also measured. Chronic WPS exposure induced a significant decrease of testosterone and estradiol, and a slight but significant increase of LH. Glutathione reductase, catalase, and ascorbic acid were significantly decreased following WPS exposure. Plasma concentration of leptin was significantly decreased by WPS exposure, whereas that of tumor necrosis factor α and interleukin 6 was significantly increased. Histopathological analysis of the testes revealed the presence of a marked reduction in the diameter of the seminiferous tubules with reduced spermatogenesis. Transmission electron microscopy examination showed irregular thickening and wrinkling of the basement membranes with abnormal shapes and structures of the spermatozoa. VEGFR1 was overexpressed in the testis of the mice exposed to WPS and was not detected in the control. The urine concentration of cotinine, the predominant metabolite of nicotine, was significantly increased in the WPS-exposed group compared with the control group. We conclude that chronic exposure to WPS induces damaging effects to the reproductive system in male mice. If this can be confirmed in humans, it would be an additional concern to an already serious public health problem, especially with the increased use of WPS use all over the world, especially in young adults.

17.
Int J Periodontics Restorative Dent ; 36 Suppl: s109-21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27031625

RESUMO

The aim of this in vivo microcomputed tomographic (µCT) study was to compare the efficacy of Mucograft (MG) vs resorbable collagen membranes (RCMs) in facilitating guided bone regeneration (GBR) around standardized calvarial defects in rats. Forty female Wistar albino rats with a mean age and weight of 6 to 9 weeks and 250 to 300 g, respectively, were used. With the rats under general anesthesia, the skin over the calvaria was exposed using a full-thickness flap. A standardized calvarial defect with a 4.6-mm diameter was created in the left parietal bone. For treatment, the rats were randomly divided into four groups (n = 10 per group): (1) defects covered with MG (MG group); (2) defects covered with an RCM (RCM group); (3) defects filled with xenograft bone particles and covered by MG (MG + bone group); and (4) defects filled with xenograft bone particles and covered by an RCM (RCM + bone group). Primary closure was achieved using interrupted resorbable sutures. The animals underwent high-resolution, three-dimensional µCT scans at baseline and at 2, 4, 6, and 8 weeks after the surgical procedures. Data regarding volume and bone mineral density (BMD) of newly formed bone (NFB) and bone particles revealed an increase in the volume of NFB in all the groups from baseline to 8 weeks. The MG group had the lowest volume of NFB (mean ± standard deviation [SD], 1.32 ± 0.22 mm(3)). No significant differences in mean ± SD values for volume of NFB were observed between the RCM (3.50 ± 0.24 mm(3)) and MG + bone (3.87 ± 0.36 mm(3)) groups, but their values were significantly lower than that of the RCM + bone group (2.95 ± 0.15 mm(3), F = 131.91, dfN = 2, dfD = 27, P < .001). Significant differences in BMD of NFB between the groups (F = 332.46, dfN = 3, dfD = 36, P < .001) and during different data collection periods (F = 97.04, dfN = 3, dfD = 36, P < .01) were observed, with the RCM group having the highest mean ± SD BMD of NFB (0.42 ± 0.05 g/mm(3)). Significant differences in the bone particle volume between the RCM + bone and MG + bone groups (F = 91.04, dfN = 1, dfD = 18, P < .05) and at different data collection periods (F = 314.12, P < .01) were observed, with the RCM + bone group displaying greater reduction in both volume (36.8%) and BMD (19.7%) of bone particles. The present in vivo µCT study demonstrated that RCM is better than MG in enhancing new bone formation in rat calvarial standardized defects when used in combination with mineralized particulate graft material.


Assuntos
Regeneração Óssea , Colágeno , Membranas Artificiais , Microtomografia por Raio-X , Animais , Feminino , Ratos , Ratos Wistar , Crânio/patologia
18.
Int J Periodontics Restorative Dent ; 36 Suppl: s139-49, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27031628

RESUMO

In vivo microcomputed tomography (µCT) enables real-time assessment of bone regeneration. The aim of this µCT and histologic experiment was to assess guided bone regeneration (GBR) around standardized calvarial defects in rats using particulate graft material (Bio-Oss) with and without collagen membranes (CMs). Eighteen female Sprague-Dawley rats aged 6 weeks and weighing 300 g were used. With the rats under general anesthesia, calvaria were exposed and a full-thickness standardized defect was created on the parietal bone. For treatment, rats were randomly assigned to the following three groups: (1) CM group; (2) Bio-Oss group; and (3) Bio-Oss + CM group. Bone volume and bone mineral density (BMD) of newly formed bone (NFB) and remnant bone particles were measured at baseline and 2, 4, 6, and 10 weeks after the operations using real-time in vivo µCT. At 10 weeks, all animals were sacrificed and calvarial tissues were assessed histologically. In the CM group, a significant increase in mean ± standard deviation (SD) BMD of NFB was observed at 6 weeks (0.32 ± 0.02 g/mm(3)) (P < .01) compared with baseline. In the Bio-Oss group, mean ± SD volume (3.03 ± 0.14 mm(3)) (P < .05) and BMD (0.14 ± 0.01 g/mm(3)) of NFB significantly increased at 6 weeks compared with baseline (P < .01). In the Bio-Oss + CM group, mean ± SD volume (0.98 ± 0.19 mm(3)) and BMD (0.13 ± 0.01 g/mm(3)) of NFB significantly increased at 4 weeks compared with baseline (P < .01). In th Bio-Oss + CM group, mean ± SD volume (3.5 ± 0.7 mm(3)) and BMD (0.44 ± 0.03 g/mm(3)) of remnant bone particles were significantly reduced at 10 weeks compared with baseline values (5.8 ± 0.96 mm(3) and 1.3 ± 0.02 g/mm(3)) (P < .05). Although histologic analysis revealed NFB in all the study groups, the Bio-Oss + CM group exhibited the most. The results of this study revealed that, in real time, new bone formation starts as early as 4 weeks in standardized calvarial defects undergoing GBR with Bio-Oss + CM, compared with new bone formation at 6 weeks in defects undergoing GBR with Bio-Oss alone.


Assuntos
Regeneração Óssea , Minerais/uso terapêutico , Crânio/patologia , Microtomografia por Raio-X , Animais , Substitutos Ósseos , Colágeno , Feminino , Ratos , Ratos Sprague-Dawley
19.
Saudi Med J ; 37(10): 1068-75, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27652356

RESUMO

OBJECTIVES: To identify genetic defects in an Omani family diagnosed with deafness.  METHODS: A cross-sectional association study was conducted at the Department of Biochemistry, College of Medicine and Health Sciences, Sultan Qaboos University, Al-Khoud, Oman and the Centre of Medical Genetics, University of Antwerp, Antwerp, Belgium between August 2010 and September 2014. Microsatellites markers for nine non-syndromic genes were used to genotype the defective locus using the extracted DNA from family members. Sanger sequencing method was used to identify the disease causative mutation. Eazy linkage 5.05 was used to calculate the logarithm of odds score. Lasergene suite was used to detect the mutation position, and Phyre2, SMART, Rasmol, and GOR IV were used to predict the effects of the defect on protein structure and function.  RESULTS: The disease was linked to markers located on chromosome-2 and covering the OTOF (DFNB9) gene. A novel missense mutation that changed nucleotide C to G at position c.1469 and consequently the amino acid Proline to Arginine (P490R) on exon 15 was detected. Protein modeling analysis revealed the impact of the mutation on protein structure and the relevant C2C domain. The mutation seems to create a new protein isoform homologous to the complement component C1q.  CONCLUSION: These findings suggest that the mutation found in C2C domain of the OTOF gene is likely to cause deafness in the studied family reflecting the importance of C2 domains of otoferlin in hearing loss.


Assuntos
Perda Auditiva Central/complicações , Perda Auditiva/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Estudos Transversais , Feminino , Perda Auditiva/complicações , Humanos , Masculino , Omã , Linhagem
20.
Front Biosci (Elite Ed) ; 8(1): 40-5, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26709644

RESUMO

HOXB13, a member of the homeobox proteins family, is a key regulator of the epithelial differentiation in the prostate gland. HOXB13 is overexpressed during malignant progression of the prostatic tissue and suspected to contribute in the pathogenesis of the prostate gland. In androgen deprived conditions, HOXB13 is thought to act through inhibition of the tumour suppressor protein p21. Since HOXB13 has a multifaceted role in ventral prostate development, its critical partners in the cascade need to be elucidated for a further understanding of its role in prostate malignancy. In this report, we review the functions attributed to HOXB13, by highlighting the most recent findings supporting the hypothesis that HOXB13 might serve as a novel biomarker for the prognosis of prostate cancer.


Assuntos
Biomarcadores Tumorais/fisiologia , Proteínas de Homeodomínio/fisiologia , Neoplasias da Próstata/patologia , Diferenciação Celular , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Proteínas de Homeodomínio/química , Humanos , Masculino , Neovascularização Patológica , Próstata/patologia , Próstata/fisiopatologia , Neoplasias da Próstata/irrigação sanguínea , Pele/fisiopatologia
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