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1.
Biologics ; 18: 147-161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38859969

RESUMO

Introduction: Osteoimmunology recognizes the relationship between bone cells and immune cells. Chronic osteoimmune dysregulation is present in bone marrow defects of the jaw (BMDJ) as fatty-degenerative osteonecrosis (FDOJ). In comparison to samples from healthy jaw bone, the cytokine analysis of samples of BMDJ/FDOJ from 128 patients showed downregulated TNF-α and IL-6 expression and the singular overexpression of the chemokine RANTES/CCL5. Aim and Objectives: This paper raises the question of whether the osteoimmune defects due to incomplete wound healing in BMDJ/FDOJ in 128 patients are related to dysregulation of the Th1/Th2 ratio and regulatory T cell (T-reg) expression in a control group of 197 BMDJ/FDOJ patients, each presenting with BMDJ/FJOD and one of seven different immune disorders. Material and Methods: In the control group, serum concentrations of the cytokines IFN-y and IL-4 were determined after stimulated cytokine release and displayed as Th1/Th2 ratios. Results: Data show a shift in Th2 in more than 80% (n = 167) of the control cohort of 197 chronically ill patients with concomitant BMDJ/FDOJ. In these 167 subjects, the Th1/Th2 ratio was <6.1 demonstrating impaired immune regulation. Forty-seven subjects or 30% showed not only a shift in Th2 but also excessive T-reg overactivation with levels of >1.900 pg/mL, indicating strongly downregulated immune activity. Discussion: BMDJ/FDOJ is characterized by a lack of Th1 cytokines and an excessive expression of RANTES/CCL5 and IL-1ra and, thus, the inversion of an acute inflammatory cytokine pattern. In contrast, abdominal fat contains a very high proportion of regulatory Th1 cells and produces an inflammatory immune response through the high overexpression of TNF-α and IL-6. The lack of Th1 activation in BMDJ/FDOJ areas inhibits normal wound healing and supports the persistence of BMDJ/FDOJ. Conclusion: The Th1/Th2 ratio requires greater consideration, especially with respect to wound healing following dental surgical interventions, such as jaw surgery, implantation and augmentation, to avoid the emergence of the osteoimmune situation that is characteristic of BMDJ/FDOJ.

2.
J Int Med Res ; 52(1): 3000605231224161, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38259068

RESUMO

OBJECTIVE: Bone marrow defects of the jaw (BMDJ) surrounding dental implants, in combination with impaired bone-to-implant contact (BIC), are difficult to detect in X-rays. This study evaluated BMDJ surrounding titanium (Ti-Impl) and ceramic (Cer-Impl) dental implants and incomplete BIC using a new trans-alveolar ultrasonography device (TAU) with numerical scaling for BIC. METHODS: The titanium stimulation test (Ti-Stim) was used to detect immune overactivation in response to titanium. Bone density surrounding implants was measured using TAU. We also validated osteoimmune dysregulation. RESULTS: TAU values showed reduced BIC and decreased osseointegration for Ti-Impl. Moreover, TAU values in the Cer-Impl group were more than twice those in the Ti-Impl cohort. The multiplex analysis of C-C motif chemokine 5 (CCL5, also known as RANTES) expression revealed a 20-fold increase in BMDJ surrounding Ti-Impl. Higher levels of CCL5 inflammation were present in the positive Ti-Stim group. CONCLUSIONS: Our data indicate that Cer-Impl have an osteoimmune advantage over Ti-Impl. The key determinant for osteoimmune sustainability appears to be the absence of inflammation at the implant site. We therefore recommend the use of TAU to assess the implant site prior to implantation.


Assuntos
Implantes Dentários , Humanos , Osseointegração , Titânio , Inflamação , Ultrassonografia , Verduras
3.
Front Immunol ; 14: 1187880, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377957

RESUMO

Due to rare but major adverse reactions to the AstraZeneca adenoviral ChAdOx1-S-nCoV-19 vaccine (ChAd), German health authorities recommended adults under 60 who received one dose of ChAd, to receive a second dose of the BioNTech mRNA BNT162b2 vaccine (BNT) as a booster. Studies in the general population suggest an enhanced efficacy of the heterologous (ChAd-BNT) compared to the homologous (BNT-BNT) vaccination regimen. However, an analysis of the efficacy in patient populations with a high risk of severe COVID-19 due to acquired immunodeficiency is still missing. We therefore compared both vaccination regimens in healthy controls, patients with gynecological tumors after chemotherapy, patients on dialysis and patients with rheumatic diseases concerning the humoral and cellular immune response. The humoral and cellular immune response differed substantially in healthy controls compared to patients with acquired immunodeficiency. Overall, the most significant differences between the two immunization regimens were found in neutralizing antibodies. These were always higher after a heterologous immunization. Healthy controls responded well to both vaccination regimens. However, the formation of neutralizing antibodies was more pronounced after a heterologous immunization. Dialysis patients, on the other hand, only developed an adequate humoral and particularly cellular immune response after a heterologous immunization. Tumor and rheumatic patients also - to a weaker extent compared to dialysis patients - benefited from a heterologous immunization. In conclusion, the heterologous COVID-19 vaccination regimens (ChAd-BNT) seem to have an advantage over the homologous vaccination regimens, especially in immunocompromised patients such as patients with end-stage kidney disease treated with hemodialysis.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Vacinas contra COVID-19/efeitos adversos , Vacina BNT162 , COVID-19/prevenção & controle , Hospedeiro Imunocomprometido , Anticorpos Neutralizantes , Imunidade , RNA Mensageiro
4.
BMC Oral Health ; 22(1): 592, 2022 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-36496367

RESUMO

BACKGROUND: The null hypotheses were tested that intraoral bone augmentation using two different allogeneic materials has no impact on the patient's blood levels of material-specific lymphocytes and on the immunohistochemical detection of pro-inflammatory cytokines IL-1α, IL1ß and TNF-α and T-cell markers CD4, CD8 in biopsies of the test groups. METHODS: In this prospective RCT, 60 systemically healthy participants were randomly assigned to two allogeneic test groups (1: Maxgraft®, freeze-dried, multiple donors, and 2: Puros®, solvent-dehydrated, single donor) and an autologous control group (10 patients). Plasma samples were collected pre-(T1) and postoperatively (2 weeks (T2) and 4 months (T3)). The Lymphocyte Transformation Test (LTT) was used for analyzing levels of transformed lymphocytes for type IV immune reactions by 3H-thymidine activity. Bone biopsies were harvested at T3 and immunohistochemically analyzed for IL-1α, IL1ß, TNF-α, CD4, CD8 and correlated with the immunological and clinical findings. RESULTS: A statistically significant difference between the tested materials was observed for LTT measurements at T3 (p = 0.033). Furthermore, three groups were identified: Group A (LTT negative T1-T3, n = 48), group B (LTT positive T1-T3, n = 7), group C (developing positive LTT at T2, n = 5). A highly significant elevation of IL-1α, IL1ß, TNF-α in patients of group C (p = 0.0001) and a significant elevation of CD4+ cells in patients of group B (p = 0.005) was shown. CONCLUSION: Our data show that following allogeneic bone grafting, local and systemic immunological reactions can be detected in some patients. These findings were statistically significant for the timepoint T3 between the tested materials as well as for the groups B and C correlated with group A for both tested materials. Therefore, the null hypotheses were rejected. A preoperative compatibility test for allogeneic materials in order to improve patient safety and the predictability of these materials would be desirable. TRIAL REGISTRATION: Ethical commission of the Ärztekammer Hamburg, Germany (PV5211) as well as by the German Registry of Clinical Studies (DRKS00013010) on 30/07/2018 ( http://apps.who.int/trialsearch/ ).


Assuntos
Transplante Ósseo , Citocinas , Humanos , Linfócitos T , Fator de Necrose Tumoral alfa , Estudos Prospectivos
5.
Microorganisms ; 10(10)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36296343

RESUMO

Vaccination against the SARS-CoV-2 virus or infection with SARS-CoV-2 will lead to the development of IgG antibodies against the S1 protein of the SARS-CoV-2 virus. However, even despite having high levels of IgG antibodies against the S1 protein of the SARS-CoV-2 virus, (re-)infection may occur. We thus examined 2994 consecutive blood samples of outpatients from the Berlin-Brandenburg area in Germany in which IgG antibodies against the S1 protein of the SARS-CoV-2 virus as well as neutralizing SARS-CoV-2 virus antibodies were determined from the same sample. When analyzing the entire study population (2994 outpatients), we saw that S1 IgG antibodies (women: 223.98 ± 3.81; men: 207.80 ± 4.59; p = 0.014) and neutralizing antibodies (women: 66.65 ± 0.82; men: 62.88 ± 1.01; p = 0.021) are slightly higher in women than in men. Curve fitting revealed a good non-linear relationship between S1 IgG and neutralizing SARS-CoV-2 antibodies. However, 51 out of the 2994 blood samples from individual subjects were positive with regard to the neutralizing antibodies and at the same time negative for S1 IgG antibodies, and 112 out of the 2994 blood samples from individual subjects were negative with regard to the neutralizing antibodies and at the same time positive for S1 IgG antibodies. In conclusion, our study shows that there is a relevant number of patients who, despite developing significant titers of S1 antibodies, do not have relevant amounts of neutralizing antibody titers and are probably at high risk of (re-)infection.

6.
Front Immunol ; 13: 915001, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36119050

RESUMO

It was shown that hypertension delays SARS CoV-2 viral clearance and exacerbates airway hyperinflammation in the respiratory tract. However, it is unknown whether hypertension determines the long-term cellular and humoral response to SARS Cov2. Health care workers (HCWs) after an outbreak of SARS Cov-2 infections were analyzed. Infected HCWs were not vaccinated before blood collection. 5-14 months (median 7 months) after detection of SARS CoV-2 infection, blood was taken to analyze humoral response (S1 IgG and SARS CoV-2 neutralizing antibodies) and cellular (T cell responses to SARS-CoV-2 with Lymphocyte Transformation Test). To identify clinical factors that determine the immune response, a multivariate regression analysis was done considering age, BMI, sex, diabetes, hypertension, smoking, COPD, asthma and time between PCR positivity and blood collection as confounding factors. Infected hypertensive HCWs more often needed to be hospitalized than non-hypertensive HCWs, but were less likely to develop anosmia and myalgia. The long-term humoral and cellular immune response was significantly strengthened in hypertensive versus normotensive infected HCWs. Multivariate regression analysis revealed that hypertension was independently associated with the humoral response to SARS CoV-2 infection. Multivariate regression analysis using same confounding factors for the humoral response showed a clear trend for an association with the cellular response to SARS CoV-2 infection as well. In conclusion, SARS CoV-2 infection strengthened immune response to SARS CoV-2 infection in hypertensive HCWs independent of other risk factors.


Assuntos
COVID-19 , Hipertensão , Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , Imunoglobulina G , SARS-CoV-2
7.
Clin Chim Acta ; 532: 130-136, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35690083

RESUMO

Both infection with and vaccination against SARS-CoV-2 trigger a complex B-cell and T-cell response. Methods for the analysis of the B-cell response are now well established. However, reliable methods for measuring the T-cell response are less well established and their usefulness in clinical settings still needs to be proven. Here, we have developed and validated a T-cell proliferation assay based on 3H thymidine incorporation. The assay is using SARS-CoV-2 derived peptide pools that cover the spike (S), the nucleocapsid (N) and the membrane (M) protein for stimulation. We have compared this novel SARS-CoV-2 lymphocyte transformation test (SARS-CoV-2 LTT) to an established ELISA assay detecting Immunoglobulin G (IgG) antibodies to the S1 subunit of the SARS-CoV-2 spike protein. The study was carried out using blood samples from both vaccinated and infected health care workers as well as from a non-infected control group. Our novel SARS-CoV-2 LTT shows excellent discrimination of infected and/or vaccinated individuals versus unexposed controls, with the ROC analysis showing an area under the curve (AUC) of > 0.95. No false positives were recorded as all unexposed controls had a negative LTT result. When using peptide pools not only representing the S protein (found in all currently approved vaccines) but also the N and M proteins (not contained in the vast majority of vaccines), the novel SARS-CoV-2 LTT can also discriminate T-cell responses resulting from vaccination against those induced by infection.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , COVID-19/diagnóstico , Proliferação de Células , Humanos , Peptídeos , Glicoproteína da Espícula de Coronavírus , Linfócitos T , Vacinação
8.
Int J Mol Sci ; 23(6)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35328706

RESUMO

Background. Local anesthetics (LAs) have potent anti-inflammatory properties. Inflammatory down-regulation is crucial in diseases with overactive immune reactions, such as acute respiratory distress syndrome (ARDS) and chronic inflammation. We investigated the influence of four LAs, procaine, lidocaine, mepivacaine, and bupivacaine, on the reduction of tumor necrosis factor-alpha (TNF-α) secretion in lipopolysaccharide (LPS)-activated human leucocytes. Methods. Blood samples of 28 individuals were stimulated with LPS. The reduction of TNF-α production by each of the four LAs added (0.5 mg/mL) was measured and correlated with biometric variables. A response was defined as reduction to <85% of initial levels. Results. All four LAs down-regulated the TNF-α secretion in 44−61%: Bupivacaine (44.4%), lidocaine (61.5%), mepivacaine (44.4%), and procaine (50% of the individuals, "responders"). The TNF-α secretion was reduced to 67.4, 68.0, 63.6, and 67.1% of the initial values in responders. The effects in both patients and healthy persons were the same. Interindividual responses to LAs were not correlated with the duration or type of complaints, basal TNF-α serum level, sex, BMI, or age of responders. Conclusions. Four clinically relevant LAs (amid-LA and ester-LA) attenuate the inflammatory response provoked by LPS. They are potential candidates for drug repositioning in treating overactive immune reactions and chronic inflammation.


Assuntos
Lipopolissacarídeos , Fator de Necrose Tumoral alfa , Anestésicos Locais/farmacologia , Anti-Inflamatórios/farmacologia , Bupivacaína/farmacologia , Humanos , Inflamação , Lidocaína/farmacologia , Lipopolissacarídeos/farmacologia , Mepivacaína , Procaína/farmacologia
9.
J Steroid Biochem Mol Biol ; 220: 106101, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35351538

RESUMO

In vitro studies indicate that 25-hydroxyvitamin D3 (25(OH)D3) and 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) inhibits the synthesis of parathyroid hormone (PTH). The degree of PTH inhibition in humans by circulating 25(OH)D and 1,25(OH)2D may be different. Moreover, age and sex as well as confounding factors like calcium and phosphate may likewise affect the relationship between vitamin D and PTH in humans. However, this was not done so far in adequately powered studies. We investigated the relationship between 25(OH)D as well as 1,25(OH)2D and intact parathyroid hormone (iPTH) in 23,134 outpatients (age mean: 59.81 years) from the Berlin-Brandenburg area of Germany with normal serum creatinine considering confounding factors like age, sex, calcium and phosphate. 25(OH)D and iPTH were inversely correlated (r = -0.17, p < 0.0001). The inverse linear correlation was observed over the entire spectrum of 25(OH)D concentrations - from low 25(OH)D concentrations to very high 25(OH)D concentrations. Multiple linear regression analysis revealed that this correlation was independent of age, sex, creatinine, calcium and phosphate (unstandardized coefficients B: -0.16, p < 0.0001). However, 1,25(OH)2D was only positively associated with iPTH in women (r = 0.05, p = 0.033) and in the subgroup of patients with lower 25(OH)D (25(OH)D< 40 ng/ml) (r = 0.09, p < 0.0001), which was also presented in multiple linear regression analysis (unstandardized coefficients B: 0.20, p = 0.001). Circulating 1,25(OH)2D does not contribute substantially to the regulation of PTH in middle aged and vitamin D sufficient outpatients from the Berlin-Brandenburg area of Germany with normal kidney function. Presumably, serum 25(OH)D that is converted to 1,25(OH)2D after uptake in the parathyroid chief cells plays the critical role.


Assuntos
Cálcio , Hormônio Paratireóideo , Vitamina D , Calcifediol , Cálcio da Dieta , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Hormônio Paratireóideo/sangue , Fosfatos , Vitamina D/sangue , Vitaminas
10.
J Clin Endocrinol Metab ; 106(9): e3739-e3747, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34406392

RESUMO

BACKGROUND: Animal studies suggested that vitamin D might decrease insulin resistance. Estrogen increased insulin sensitivity and glucose tolerance in rodents. However, sex-specific association of vitamin D with insulin resistance in humans remains unclear. OBJECTIVES: To investigate the sex-dependency of the association of insulin resistance and 25-hydroxyvitamin D [25(OH)D] in a large Caucasian population. METHODS: Cross-sectional study from out-patients' blood samples with measurements of 25(OH)D and homeostatic model assessment of insulin resistance (HOMA-IR) drawn at exactly the same day (n = 1887). This cohort was divided into 3 groups: (1) group with vitamin D deficiency (n = 1190), (2) group with vitamin D sufficiency (n = 686), and (3) vitamin D excess groups (n = 11); the vitamin D excess group was excluded from further analysis due to the small size. RESULTS: Analysis of the entire study population showed that serum 25(OH)D was inversely associated with HOMA-IR [Spearman correlation coefficient (rs) = -0.19, P < 0.0001]. When considering the vitamin D status, this association was only seen in the vitamin D deficiency group but not in the vitamin D sufficient group. The correlation was sex-dependent: HOMA-IR was inversely correlated with vitamin D in women with vitamin D deficiency (rs = -0.26, P < 0.0001) but not in men with vitamin D deficiency (rs = 0.01, P = 0.714). After multivariate linear regression analysis considering confounding factors, this relationship was again only seen in women. CONCLUSION: Vitamin D was inversely and independently associated with insulin resistance only in women with vitamin D deficiency. Based on our data, we suggest that in particular vitamin D deficient women might benefit from vitamin D substitution by improving insulin resistance. This, however, needs to be proven in adequately designed double-blind placebo-controlled clinical studies.


Assuntos
Resistência à Insulina , Vitamina D/sangue , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , Método Duplo-Cego , Feminino , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Caracteres Sexuais , Vitamina D/análogos & derivados , Deficiência de Vitamina D/sangue
11.
Artigo em Inglês | MEDLINE | ID: mdl-34262389

RESUMO

BACKGROUND: The role played by signaling pathways in the cell-cell communication associated with multiple sclerosis (MS) progression has become a critical area in research. Chemokine RANTES (regulated upon activation, normal T-cell expressed and secreted), also named chemokine C-C motif ligand 5 (CCL5; R/C), is a protein that has been investigated in neuroinflammatory research due to its link to MS development. OBJECTIVE: Research on bone marrow defects in the jawbone (BMDJ), which morphologically presents as fatty-degenerative osteonecrosis of the jawbone (FDOJ), presents overexpression of R/C signaling in affected areas. Here, we try to elucidate the potential link between jawbone-derived R/C and MS. METHODS: Seventeen BMDJ/FDOJ samples extracted from 17 MS patients, as well as samples from 19 healthy controls, were analyzed for R/C expression using bead-based Luminex® analysis. The serum R/C levels from 10 MS patients were examined. Further, bone density, histology, and R/C expression were analyzed in two clinical case studies. RESULTS: High R/C overexpression was found in all BMDJ/FDOJ samples obtained from the MS group. Serum R/C levels were also upregulated in the MS group. R/C serum levels in the MS cohort were higher than in the healthy controls. In contrast, the histology of BMDJ/FDOJ samples showed no inflammatory cells. DISCUSSION: R/C-induced "silent inflammation" in MS is widely discussed in the scientific literature, along with R/C triggering of inflammation in the central nervous system, which might be key in the development of MS. CONCLUSION: The authors suspect that BMDJ/FDOJ may serve as a trigger of MS progression via R/C overexpression. As such, the dental and medical communities should be made aware of BMDJ/FDOJ in cases of MS.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33859496

RESUMO

BACKGROUND: The role of signaling pathways as part of the cell-cell communication within cancer progression becomes a crucial area. Chemokine RANTES (regulated upon activation, normal T-cell expressed and secreted), also known as the chemokine C-C motif ligand 5 (CCL5) (R/C), is a protein on which cancer research focus due to its link with aggressive cancer development. OBJECTIVE: Research on fatty-degenerative osteonecrosis in jawbone (FDOJ) shows striking overexpression of R/C in these areas. Here we try to elucidate a potential link between jawbone-derived R/C and breast cancer (BC) and compare these findings by immunohistochemical staining. METHODS: Thirty-nine FDOJ samples extracted from 39 BC patients and samples from 19 healthy control were analyzed for R/C expression using bead-based Luminex® analysis. R/C levels from 5 BC patients were measured in serum before and after FDOJ surgery. Bone density, histology, R/C expression, and immunohistochemistry were analysed in 4 clinical case studies. The R/C staining of two FDOJ BC patients is compared with the immunohistochemical staining of BC cell preparations. RESULTS: A high overexpression of R/C was seen in all FDOJ samples. R/C levels in serum were statistically downregulated after FDOJ surgery (p=0.0241). DISCUSSION: R/C induced "silent inflammation" in BC is widely discussed in scientific papers along with R/C triggering of different signaling pathways, which might be a key point in the development of BC. CONCLUSION: Hypothesis that FDOJ may serve as a trigger of BC progression through R/C overexpression was set by the authors, who thus inspire clinicians to make aware of FDOJ throughout the dental and medical community in BC cases.

13.
J Inflamm Res ; 14: 1603-1612, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33911892

RESUMO

BACKGROUND: Cytokines, especially chemokines, are of increasing interest in immunology. This study characterizes the little-known phenomenon of "bone marrow defects of the jawbone" (BMDJ) with known overexpression of the chemokine RANTES/CCL5 (R/C). PURPOSE: Our investigation clarifies why BMDJ and the intensity of local R/C overexpression are challenging to detect, as examined in patients with seven different systemic immunological diseases. Specifically, we investigate whether R/C overexpression is specific to certain disease groups or if it represents a type of signal disruption found in all systemic immunological diseases. PATIENTS AND METHODS: In a total of 301 patients, BMDJ was surgically repaired during clinical practice to reduce "silent inflammation" associated with the presence of jaw-related pathologies. In each case of BMDJ, bone density was measured preoperatively (in Hounsfield units [HU]), while R/C expression was measured postoperatively. Each of the 301 patients suffered from allergies, atypical facial and trigeminal pain, or were diagnosed with neurodegenerative diseases, tumors, rheumatism, chronic fatigue syndrome, or parasympathetic disorders. RESULTS: In all BMDJ cases, strongly negative HU values indicated decreased bone density or osteolysis. Consistently, all cases of BMDJ showed elevated R/C expression. These findings were consistently observed in every disease group. DISCUSSION: BMDJ was confirmed in all patients, as verified by the HU measurements and laboratory results related to R/C expression. The hypothesis that a specific subset of the seven disease groups could be distinguished either based on the increased presence of BMDJ and by the overexpression of R/C could not be confirmed. A brief literature review confirms the importance of R/C in the etiology of each of the seven disease groups. CONCLUSION: In this research, the crucial role played by BMDJ and the chemokine R/C in inflammatory and immune diseases is discussed for seven groups of patients. Each specific immune disease can be influenced or propelled by BMDJ-derived R/C inflammatory signaling pathways.

14.
J Steroid Biochem Mol Biol ; 210: 105877, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33741448

RESUMO

Measurements of total 25-hydroxyvitamin D (t25(OH)D) are currently primarily used to assess the vitamin D status. The lipophilic cell membrane can only be passed by the un-bound form of 25-hydroxyvitamin D: free 25-hydroxyvitamin D (f25(OH)D). It is thought that f25(OH)D does reflect its biological actions better than t25(OH)D. However, as of today, there are no established guidelines for the clinical use of f25(OH)D. We analysed 5060 patients with simultaneous measurements of free and total 25(OH). Linear regression was used to study the relationship between free 25(OH)D and total 25(OH)D. We reviewed and used the established t25(OH)D reference values and determined the slope of the relationship between them to calculate reference values for f25(OH)D. F25(OH)D and t25(OH)D showed a strong positive linear (r = 0.8395, p < 0.0001) correlation. The slope of the relationship was 0.2833 ± 0.00257. The recommended threshold level of f25(OH)D is 8.499 pg/mL, corresponding to a target concentration for t25(OH)D of at least 30 ng/mL considered as sufficient in most of the international vitamin D guidelines. The upper limit for vitamin D is less clear in the guidelines. Most experts favour an upper limit for t25(OH)D of 100 ng/mL. This is equivalent to 28.330 pg/mL f25OHD. We established based on international guidelines for t25(OH)D reference values for f25(OH)D that are urgently needed for clinical use of f25(OH)D. However, clinical studies with f25(OH)D to confirm our suggestions are needed but will take time.


Assuntos
Vitamina D/análogos & derivados , Adulto , Análise Química do Sangue , Cálcio/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Valores de Referência , Vitamina D/sangue
15.
Clin Cosmet Investig Dent ; 13: 21-37, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33505172

RESUMO

INTRODUCTION: Bisphosphonate (BP)-related osteonecrosis of the jaw (BRONJ) is a complication of intravenous (IV) BP therapy. BP therapy locally affects the dentoalveolar area, while systemic effects are associated with parenteral/IV BP use. Despite numerous publications, the pathogenesis of BRONJ is not fully understood, as only some patients receiving IV BPs develop BRONJ. PURPOSE: Can impaired bone remodeling (found in aseptic-ischemic osteonecrosis of the jaw [AIOJ], bone marrow defects [BMD], or fatty-degenerative osteonecrosis of the jaw [FDOJ]) represent a risk factor for BRONJ formation? PATIENTS AND METHODS: A literature search clarified the relationship between AIOJ, BMD, FDOJ, and BRONJ, in which common characteristics related to signal cascades, pathohistology, and diagnostics are explored and compared. A case description examining non-exposed BRONJ is presented. DISCUSSION: Non-exposed BRONJ variants may represent one stage in undetected BMD development, and progression to BRONJ results from BPs. CONCLUSION: Unresolved wound healing at extraction sites, where wisdom teeth have been removed for example, may contribute to the pathogenesis of BRONJ. With IV BP administration, persisting AIOJ/BMD/FDOJ areas may be behind BRONJ development. Therapeutic recommendations include IV BP administration following AIOJ/BMD/FDOJ diagnosis and surgical removal of ischemic areas. BPs should not be regarded as the only cause of osteonecrosis.

16.
Clin Cosmet Investig Dent ; 12: 205-216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801922

RESUMO

INTRODUCTION: The presently used impulse echo ultrasound examination is not suitable to provide relevant and reliable information about the jawbone, because ultrasound (US) almost completely reflects from the hard cortical jawbone. At the same time, "focal osteoporotic bone marrow defects" (BoneMarrowDefects = BMD) in jawbone are the subject of scientific presentations and discussions. PURPOSE: Can a newly developed trans-alveolar ultrasonic sonography (TAU-n) device locate and ascertain BMD? PATIENTS AND METHODS: TAU-n consists of a two-part handpiece with an extraoral ultrasound transmitter and an intraoral ultrasound receiver. The TAU-n computer display shows the different jawbone densities with corresponding colour coding. The changes in jawbone density are also displayed numerically. The validation of TAU-n readings: A usual orthopantomogram (2D-OPG) on its own is not suitable for unequivocally determining jawbone density and has to be excluded from this validation. For validation, a 3D-digital volume tomogram@/cone beam computer tomogram (DVT@/CBCT) with the capacity to measure Hounsfield units (HU) and a TAU-n are used to determine the presence of preoperative BMD in 82 patient cases. Postoperatively, histology samples and multiplex analysis of RANTES@/CCL5 (R@/C) expression derived from surgically cleaned BMD areas are evaluated. RESULTS: In all 82 bone samples, DVT-HU, TAU-n values and R/C expressions show the presence of BMD with chronic inflammatory character. However, five histology samples showed no evidence of BMD. All four evaluation criteria (DVT-HU, TAU-n, R/C, histology) confirm the presence of BMD in each of the 82 samples. CONCLUSION: The TAU-n method almost completely matches the diagnostic reliability of the other methods. The newly developed TAU-n scanner is a reliable and radiation-free option to detect BMD.

17.
EPMA J ; 10(4): 351-364, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31832111

RESUMO

BACKGROUND: Fatty degenerative osteonecrosis in the medullary spaces of the jawbone (FDOJ) may be identified as a lesser known source of RANTES/CCL5 (R/C) overexpression. The chemokine R/C also interferes with bone metabolism leading to osteolysis in areas affected by FDOJ. Many dental surgeries require functioning repair mechanisms and these may be disrupted by R/C overexpression. OBJECTIVE: To clarify the way in which R/C expression from adipocytes in FDOJ causes a disturbance in osteogenesis and impacts on medullary stem cells by investigating the detection of R/C expression with immunochemical staining. MATERIALS AND METHODS: We examined the tissue samples of 449 patients with FDOJ to assess the level of the chemokine R/C using bead-based Luminex® analysis. In six clinical case studies of FDOJ, we compared bone density, histological findings, R/C expression, and immunohistochemical staining. RESULTS: R/C is overexpressed by up to 30-fold in the 449 FDOJ cases when compared with healthy jawbone samples. The comparison of the six clinical cases consistently shows greatly reduced bone density, (i.e., osteolysis), but varies in terms of the level of agreement across the other three parameters. DISCUSSION: R/C from FDOJ sources may be implicated in several immune responses and considered a key pathogenetic pathway for increased adipogenesis rather than desirable osteogenesis. Adipocytes pathogenetically act via R/C expression in local FDOJ and systemically on the immune system. CONCLUSION: R/C may be regarded as an important trigger for possible pathological developments in the fate of hematopoietic stem cells. FDOJ is not a rigidly uniform process but reflects changing stages of development. The absence of correlating findings should not be interpreted as a misdiagnosis. It seems appropriate to direct further research in the field of "maxillo-mandibular osteoimmunology" focusing on R/C overexpression in FDOJ areas. This may contribute to the development of personalized strategies in preventive medicine.

18.
Clin Cosmet Investig Dent ; 10: 251-262, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519117

RESUMO

BACKGROUND: The immune and bone systems are closely linked via cytokine cross-talk. This interdisciplinary field of research is referred to as osteoimmunology and pertains to inflammatory and osteoarticular diseases that feature the primary expression of tumor necrosis factor-alpha (TNF-α) and IL-6. OBJECTIVE: Are there bone resorptive processes wherein chronic inflammatory conditions are not linked to TNF-α and IL-6 expression, but rather to the expression of other cytokines? MATERIALS AND METHODS: A comprehensive literature search was performed in PubMed Central. DISCUSSION: Although all diseases with cytokines involved in bone resorption (TNF-α and IL-6) are at the forefront of destructive inflammatory processes, there is one exception in the literature: fatty oxide osteoporosis/osteolysis in the jawbone (FDOJ), which is associated with significant bone softening. However, it should be noted that TNF-α and IL-6 fall below the levels found in a healthy jawbone in this condition. Another conspicuous finding is that there is a nearly 35-fold overexpression of the chemokine RANTES/CCL5 (R/C) in all FDOJ cases studied thus far in the literature. CONCLUSION: FDOJ appears to represent a unique cytokine and inflammatory pattern from osteolysis in the body. R/C can be defined as the dominant carrier of a "maxillomandibular osteoimmunology".

19.
EPMA J ; 9(3): 331-343, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30174768

RESUMO

BACKGROUND AND INTRODUCTION: It is a well-known fact that titanium particles deriving from dental titanium implants (DTI) dissolve into the surrounding bone. Although titanium (TI) is regarded as a compatible implant material, increasing concern is coming up that the dissolved titanium particles induce inflammatory reactions around the implant. Specifically, the inflammatory cytokine tumor necrosis factor-alpha (TNF-α) is expressed in the adjacent bone. The transition from TNF-α-induced local inflammation following insertion of DTI surgery to a chronic stage of "silent inflammation" could be a neglected cause of unexplained medical conditions. MATERIAL AND METHODS: The signaling pathways involved in the induction of cytokine release were analyzed by multiplex analysis. We examined samples of jawbone (JB) for seven cytokines in two groups: specimens from 14 patients were analyzed in areas of DTI for particle-mediated release of cytokines. Each of the adjacent to DTI tissue samples showed clinically fatty degenerated and osteonecrotic medullary changes in the JB (FDOJ). Specimens from 19 patients were of healthy JB. In five cases, we measured the concentration of dissolved Ti particles by spectrometry. RESULTS: All DTI-FDOJ samples showed RANTES/CCL5 (R/C) as the only extremely overexpressed cytokine. DTI-FDOJ cohort showed a 30-fold mean overexpression of R/C as compared with a control cohort of 19 healthy JB samples. Concentration of dissolved Ti particles in DTI-FDOJ was 30-fold higher than an estimated maximum of 1.000 µg/kg. DISCUSSION: As R/C is discussed in the literature as a possible contributor to inflammatory diseases, the here-presented research examines the question of whether common DTI may provoke the development of chronic inflammation in the jawbone in an impaired state of healing. Such changes in areas of the JB may lead to hyperactivated signaling pathways of TNF-α induced R/C overexpression, and result in unrecognized sources of silent inflammation. This may contribute to disease patterns like rheumatic arthritis, multiple sclerosis, and other systemic-inflammatory diseases, which is widely discussed in scientific papers. CONCLUSION: From a systemic perspective, we recommend that more attention be paid to the cytokine cross-talk that is provoked by dissolved Ti particles from DTI in medicine and dentistry. This may contribute to further development of personalized strategies in preventive medicine.

20.
Clin Cosmet Investig Dent ; 9: 99-109, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29184447

RESUMO

Of the definitions listed in the International Statistical Classification of Diseases and Related Health Problems, tenth revision (ICD-10), two disease descriptions can be found together: "idiopathic aseptic bone necrosis" and "avascular bone necrosis." The relevant literature on both the conditions abbreviates both as "aseptic ischemic osteonecrosis in the jawbone" (AIOJ). To shed light on the clinical details of this condition, osteolytic jawbone samples of 24 patients with different systemic immunological diseases were examined using four steps: presurgical dental X-ray, postsurgical histology, polymerase chain reaction DNA analysis (PCR DNA) of bacteria, and RANTES/CCL5 (R/C) expression. These four steps showed that neither X-ray nor histology delivered unambiguous results with respect to inflammatory processes; furthermore, the PCR results did not show evidence of any microbial load within the jaw samples. However, there is a striking, coherent overexpression of chemokine R/C in the AIOJ samples. This study proved the aseptic existence of "silent inflammation" within the jawbone. The ICD-10 (AIOJ) definition, which is hard to interpret, can now be substantiated with clinical evidence, while the cytokine expressions described in this report can explain the systemic immunological effects observed within the group of examined patients.

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