RESUMEN
Fixture fracture is the most catastrophic failure of implant components because it usually causes the loss of the implant. Nevertheless, the osseointegrated fractured implants represent a very useful opportunity to study in humans the effects of loading to the peri-implant bone microstructure. The aim of the present study was to evaluate the interplay between microstructure and function of the bone around an implant retrieved from human maxilla after 13 years. There was 1 fractured Dental Implant Line (sand blasted surface from a patient placed in the anterior region of the maxillary bone (2.1) after a bone augmentation procedure, and it was processed for histology. The specimen was analyzed under the scanning electron microscope (SEM), the confocal scanning laser microscope (CSLM) and brightfield light microscope (LM) equipped with circularly polarized light (CPL). The BIC rate of the implant retrieved after 13 years was (mean ±SD) 68.7 ± 3.7. The crestal bone down the implant platform damage appeared to be under modeling process. The transverse collagen fiber orientation (CFO) (mean ±SD) under the lower flank of the threads was 20.4 ± 3.5 x 10(4) pixel while the longitudinal CFO was 19.8 ± 2.8 x 10(4) pixel (P>.05). In the inter-threads region the transverse CFO (mean ±SD) was 15.0 ± 4.0 x 10(4) pixel while the longitudinal CFO was 21.4 ± 3.0 x 10(4) pixel (P>.05). The osteocytes numbers (mean ±SD) was 130 ∓ 34. Under SEM with back scattered electrons (BSE) signal the peri-implant bone appears mainly lamellar and highly mature with several osteons organized in the implant inter-threads areas. The fracture of the implant was most probably correlated to a fatigue of the material mainly associated to a damage of the internal coil. Surprisingly, it was noted a lack of implant site-specific CFO of the bone extracellular matrix facing the threaded dental implant notwithstanding the high level of BIC rate.
Asunto(s)
Implantes Dentales , Maxilar/patología , Recuento de Células , Colágeno/metabolismo , Fracaso de la Restauración Dental , Femenino , Humanos , Maxilar/metabolismo , Maxilar/ultraestructura , Microscopía/métodos , Persona de Mediana Edad , Osteocitos/citologíaRESUMEN
The aim of the present study was to evaluate the interplay between microstructure and function of the bone around an immediately loaded implant retrieved from human maxilla after 23 months due to fracture. A spiral implant of 3.3 mm x 15 mm was placed in a male 53 years old in the anterior region of the mandible bone (4.1) and it was processed for histology. The specimen was analyzed under the confocal scanning laser microscope (CSLM) and brightfield light microscope (LM) equipped with circularly polarized light (CPL). The BIC rate was 76.7 ± 4.9 (mean ±SD). Many cement lines indicates an high remodeling rate of the bone. The transverse collagen fiber orientation (CFO) (mean±SD) under the lower flank of the thread near the tread tip was 55.2 ± 4.8 x 10(4) pixel while the longitudinal CFO was 45.8 ± 2.3 x 10(4) pixel (P<.05). In the inter-threads region the transverse CFO (mean ±SD) was 36.4 ± 2.4 x 10(4) pixel while the longitudinal CFO was 65.6 ± 6.5 x 10(4) pixel (P<.05). The osteocytes numbers (mean ±SD) was 205 ± 45 in the peri-implant bone and 144 ± 53 in the native bone (P=.007). After 2-years of loading the SLA spiral implant was well osseointegrated but still surrounded by woven bone. The osteocytes density was significantly higher in the peri-implant bone than in the native bone. The transverse collagen fibers were significantly associated with the lower flank of the implant threads, while the longitudinal collagen fibers were more represented in the straight surface of the implant. The implant fracture was correlated to crestal bone resorbing and subsequent fatigue yielding.
Asunto(s)
Implantes Dentales , Mandíbula/patología , Recuento de Células , Colágeno/metabolismo , Fracaso de la Restauración Dental , Humanos , Masculino , Mandíbula/metabolismo , Microscopía/métodos , Persona de Mediana Edad , Osteocitos/citologíaRESUMEN
Studying discovertebral complex anatomy is extremely important for the understanding of the pathophysiology of disc degeneration which leads to vertebral endplates signal changes, also known as Modic changes.The sequelae of disc degeneration are among the leading causes of functional incapacity in both sexes and are one of the most common sources of chronic disability in the working years. Even if the presence of degenerative changes in MRI of the spine is by no means an indicator of symptoms, we are concordant in a positive association between Modic changes and low back pain, above all as a relatively specific but insensitive sign of discogenic low back pain.
Asunto(s)
Médula Ósea/patología , Degeneración del Disco Intervertebral , Dolor de la Región Lumbar , Vértebras Lumbares/patología , Progresión de la Enfermedad , Humanos , Degeneración del Disco Intervertebral/complicaciones , Degeneración del Disco Intervertebral/diagnóstico , Degeneración del Disco Intervertebral/epidemiología , Dolor de la Región Lumbar/complicaciones , Dolor de la Región Lumbar/diagnóstico , Dolor de la Región Lumbar/epidemiología , Imagen por Resonancia Magnética/métodos , Estadística como AsuntoRESUMEN
INTRODUCTION: Diffuse midline glioma is a newly WHO defined entity (grade IV) (Louis et al., 2016) which includes diffuse intrinsic pontine glioma (DIPG) reported in pediatric population and, occasionally, in young adults. Here, we present a detailed description of an atypical case of diffuse midline glioma in a 53â¯years old woman. CASE REPORT: A caucasian woman aged 53 from Ukraine, was referred to another neurological department complaining of 3â¯months history of progressive postural instability and gait impairment with frequent falling. Magnetic resonance demonstrated two brainstem lesions, hyperintense in FLAIR with "patchy" peripheral enhancement, leptomeningeal and cranial nerves enhancement. CSF was normal. Due to positive antinuclear antibodies test (ANA 1:360), intravenous steroid treatment was administered and reported to initially improve the patient condition. However, the following weeks the lady worsened. Imaging features were unchanged. Because quantiferon test resulted positive, MRI-Spectroscopy showed an inflammatory pattern and MRI perfusion study and brain FDG-PET, were normal, tubercolar granulomatous hypothesis was initially favored. Antitubercular therapy with isoniazid, pyrazinamide, ethambutol and rifampicin was started without any clinical improvement. Hence, the biopsy was proposed. The procedure revealed a diffuse midline pontine glioma. Considering the advanced stage of the disease, radiotherapy was not indicated. Patient died after eight months from the onset of neurological disturbances. CONCLUSION: Our case shows that diffuse midline glioma is a CNS tumor not limited to young population but occurring also in middle aged patients with an insidious pattern. We therefore recommend to perform biopsy at very early stages in patients with atypical brainstem lesions.
Asunto(s)
Neoplasias del Tronco Encefálico/diagnóstico , Neoplasias del Tronco Encefálico/patología , Glioma/diagnóstico , Glioma/patología , Puente/patología , Femenino , Humanos , Persona de Mediana EdadRESUMEN
This study was aimed at revealing the relationship between the serum concentrations of lipoprotein(a) [Lp(a)], the coronary atherosclerotic disease (CAD) and the cerebral vasculopathies (CVP) in elderly patients. A group of 117 patients (66 women and 51 men, mean age 83 +/- 5.8 years) was investigated. Of them, 58 suffered from acute myocardial infarct (AMI) and 59 from ictus cerebri (IC). The parameters were compared with those obtained from a control-group of 88 old people without any recent clinical history of cerebrovasculopathy or atherosclerotic coronariopathy. In the patients with AMI, the average serum value of Lp(a) was 40.8 +/- 18.5 mg%, and in those suffering from IC, it was 46.7 +/- 13.2 mg%; the differences of these averages against the mean found in the control patients (23.2 +/- 11.5 mg%) were statistically significant (p < 0.01). One can conclude that an increased Lp(a) is of diagnostic value for the presence of both IC and AMI, and represents a risk factor for cerebrovasculopathies, too.
RESUMEN
Lipoprotein(a) was discovered by chance by Berg in 1963; after twenty years of research, the chemical, physical and metabolic characteristics of Lp(a) are now known. This lipoprotein forms the missing link between the lipid metabolism and the coagulation-fibrinolysis process. The A. describe its similarity to plasminogen, its capacity to delay coagulum or embolus destruction and highlight its structural and functional similarity to lipid metabolism. To day, a total of 6 Lp(a) isoforms have been identified with different molecular weights: in addition, the inverse proportion between the isoforms' molecular weight and Lp(a) plasma concentration has been demonstrated. Lp(a) is not the product of the metabolism of other lipoproteins nor is it a catabolite of LDL; it is produced ex-novo and does not apparently exchange its proteic fraction with other lipoproteins. The paper also examines the question of whether Lp(a) is a plasma marker which increases during the formation of atherosclerotic plaque or whether it should not be considered an atherogenetic factor. To this end the possible mechanisms by which Lp(a) is deposited in plaque are examined. Lastly, the paper reviews all studies concerning the relationship between Lp(a), ischemic cardiopathy and cerebrovascular disease.
Asunto(s)
Arteriosclerosis/etiología , Lipoproteína(a)/sangre , Anciano , Arteriosclerosis/sangre , Arteriosclerosis/diagnóstico , Trastornos Cerebrovasculares/sangre , Trastornos Cerebrovasculares/etiología , Ensayos Clínicos como Asunto , Femenino , Humanos , Hiperlipidemias/complicaciones , Hiperlipoproteinemia Tipo II/complicaciones , Hipertensión/complicaciones , Lípidos/sangre , Lipoproteína(a)/genética , Lipoproteína(a)/metabolismo , Lipoproteínas/sangre , Masculino , Peso Molecular , Isquemia Miocárdica/sangre , Isquemia Miocárdica/etiología , Plasminógeno/análisis , Factores de Riesgo , Fumar/efectos adversosRESUMEN
Recently many studies have been leaded out to identify the risk factors for development of atherosclerosis in cerebral vessels. To value the relationship between lipidic parameters with lipoprotein(a) and the degree of atherosclerotic stenosis of carotids, we have examined with colorsonographic assay the carotid vessels in a sample of 292 patients (171 men, 117 women, average age 71 years, DS +/- 12); we have measured the concentration of lipidic parameters [total cholesterol, HDL cholesterol, LDL cholesterol, Apo A, Apo B100, triglycerides and Lp(a)]. HDL Cholesterol showed an inverse relationship to carotid atherosclerosis: that relationship was not statistically significant. Men had much more atherosclerosis than women (p < 0.05) and the degree of stenosis was related to age (p < 0.01). Only in patients under 70 years old, total cholesterol concentration showed a positive association with the size of the atherosclerotic plaques. Lp(a) was neither associated with the degree of carotid atherosclerotic stenosis in all patients of our sample or when selected for age.
Asunto(s)
Arteriosclerosis/epidemiología , Enfermedades de las Arterias Carótidas/epidemiología , Colesterol/sangre , Lipoproteína(a)/sangre , Triglicéridos/sangre , Factores de Edad , Anciano , Anciano de 80 o más Años , Arteriosclerosis/sangre , Arteriosclerosis/etiología , Enfermedades de las Arterias Carótidas/sangre , Enfermedades de las Arterias Carótidas/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores SexualesRESUMEN
In this study we evaluated the several risk-factors, Lp(a) and lipids order, related to the family history for ischaemic cardiovascular disease (CHD) atherosclerotic cerebrovasculopathy and arterious hypertension, in a healthy adolescent group, to stress possible early and significant alteration of the lipids order and Lp(a); we also considered which of these parameters may be considered the risk factor most closely related to family history. We studies 130 healty high school students, mean age 16.5 +/- 5.5 years, selected in four groups related to the family history: the first one composed of 34 subjects with positive family history for CHD; the second one of 32 subjects with positive family history for cerebral infarction (CI); the third by 32 subjects with family history for arterial hypertension and the last group by 30 control subjects. Mean value of all variables considered was in the normality range. Lp(a) resulted in the normality range with the exception of the group with positive family history for CHD. Also the traditional risk factors (Total-Col., LDL/Col. and Triglycerides) were increased in this group. Besides the differences between the mean of Lp(a) and Total/Col. in the group with positive family history for CHD and in the control group were statistically significant. The results showed that Lp(a), even if it cannot replace the family history in the screening of coronary atherosclerotic disease, might be considered a risk marker of early atherosclerotic disease.
Asunto(s)
Infarto Cerebral/epidemiología , Enfermedad Coronaria/epidemiología , Hipertensión/epidemiología , Lípidos/sangre , Lipoproteína(a)/sangre , Adolescente , Factores de Edad , Apolipoproteínas A/sangre , Apolipoproteínas B/sangre , Infarto Cerebral/sangre , Niño , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Enfermedad Coronaria/sangre , Humanos , Hipertensión/sangre , Valores de Referencia , Factores de Riesgo , Triglicéridos/sangreRESUMEN
An epidemiological study was performed in a group of secondary school students selected according to their family history to assess whether changes exist in blood viscosity and intraerythrocytic calcium levels in young healthy subjects with positive family histories of arterial hypertension or cerebral and cardiac ischemic vasculopathies, compared to a control group with a negative family history of these disorders. A population of 130 secondary school students without any pathologies were subdivided into 4 groups: 1) with a positive family history of ischemic cardiopathy (ICP); with a positive family history of cerebral ictus; 3) with a family history of arterial hypertension; 4) a negative family history of these diseases. Total blood viscosity, hematocrit, plasma fibrinogen and intraerythrocytic calcium was evaluated in all groups. The results show that these parameters were within the normal range, as was to be expected in healthy subjects. Blood viscosity was also normal in all groups; intraerythrocytic calcium levels were slightly higher in groups with histories of cardiovascular disease and in particular there was an increased percentage of cases with values above the threshold level. Higher fibrinogen levels were also recorded, but always within the normal range, in the group with a positive history of ICP. The epidemiological study is important to assess whether a family pattern of cardiovascular disease can also influence such independent risk parameters as blood viscosity and intraerythrocyte calcium, owing to the possible greater frequency of development of cardiovascular disease.
Asunto(s)
Viscosidad Sanguínea , Calcio/sangre , Eritrocitos/química , Adolescente , Isquemia Encefálica/sangre , Isquemia Encefálica/epidemiología , Isquemia Encefálica/genética , Fibrinógeno/análisis , Hematócrito , Humanos , Hipertensión/sangre , Hipertensión/epidemiología , Hipertensión/genética , Italia/epidemiología , Isquemia Miocárdica/sangre , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/genéticaRESUMEN
The aim of this study was to evaluate Lp(a), total, HDL and LDL cholesterol, triglycerides, Apo A and Apo B100 plasmatic concentrations in patients affected by nephrotic syndrome that is known able to increase the ratio of the risk of cerebral and cardiovascular events, in comparison with a group of healthy patients homologous for sex and age. In the group of patients with nephrotic syndrome we have compared the variables between diabetic mellitus type I patients and non diabetic patients. All the variables, in exception of HDL cholesterol, were significantly increased in the group of patients with nephrotic syndrome compared with the control group. HDL-cholesterol concentration was significantly higher in controls than in nephrotic patients. Diabetic and nephrotic patients showed increased levels of Lp(a) concentration than non diabetic patients and the difference was statistically confirmed. These data suggest that Lp(a) acts really like a risk factor for atherosclerotic disease, being elevated in patients characterized for increased risk for cerebral and cardiovascular events because of the presence of nephrotic syndrome. Moreover we can suppose that elevated plasmatic Lp(a) levels in nephrotic patients could be linked to increased synthesis of proteins in the liver as physiological reaction to severe proteinuria.
Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Nefropatías Diabéticas/sangre , Lípido A/sangre , Síndrome Nefrótico/sangre , Anciano , Enfermedad Crónica , Colorimetría , Diabetes Mellitus Tipo 1/complicaciones , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lípidos/sangre , MasculinoRESUMEN
Fasting hypoglycemia is frequently observed in patients with Multiple Sclerosis (S.M.) showing orthostatic hypotension and defective thermoregulation, although they never complicate in hypoglycemic coma. The aim of this study was to evaluate glucose homeostasis in S.M. patients. Both insular and counter-insular regulating mechanisms were investigated by determination of glucose, insulin, C-peptide and cortisol plasmatic levels during OGTT, and subsequently by evaluating glucagon plasmatic levels after arginine administration (30 g., i.v.). Our results suggest that the increased susceptibility of S.M. patients to undergo fasting hypoglycemia could be related to some alterations in counter-insular mechanisms, generally included among neurovegetative modifications in S.M. patients and probably due to orthosympathetic function impairment.