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1.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 53(1): 108-115, 2024 Jan 31.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38310084

RESUMEN

OBJECTIVES: To explore the effects of online mindfulness-based stress reduction (MBSR) on the anxiety and depression status, and quality of life in the caregivers of patients with severe mental disorders. METHODS: Ninety-three caregivers for patients with schizophrenia or bipolar disorder, who were hospitalized in Yunnan Provincial Mental Hospital in March 2021, were enrolled and randomly divided into control group (n=47) and MBSR intervention group (n=46). Both groups received basic health education and rehabilitation skill training, while the intervention group received additional online MBSR for 8 weeks. The anxiety and depression status, and the quality of life of the caregivers were evaluated by Self-rating Anxiety Scale (SAS), Self-rating Depression Scale (SDS) and the 36-item Short Form Health Survey (SF-36) before and 8 weeks after intervention, respectively. RESULTS: Thirteen caregivers dropped out of the study, and 80 subjects (40 in each group) were included in the final analysis. At the baseline, there were no significant differences in SAS, SDS and SF-36 scores between two groups (all P>0.05). Compared with the baseline, SAS and SDS scores in the intervention group significantly decreased after 8 weeks of intervention (both P<0.01) and were significantly lower than those in the control group (both P<0.01). There were no significant changes in the control group (all P>0.05). Except the physiological function dimension, the total score and the scores of each dimension of SF-36 in the intervention group were significantly increased after 8-week intervention (all P<0.05), and were significantly higher than those in the control group (all P<0.01). There were no significant changes in the control group before and after intervention (all P>0.05). CONCLUSIONS: Online MBSR can reduce the anxiety and depression levels, improve the quality of life in the caregivers of patients with severe mental disorders.


Asunto(s)
Trastornos Mentales , Atención Plena , Humanos , Calidad de Vida , Cuidadores , Depresión/terapia , China , Ansiedad/terapia
2.
Acta Trop ; 251: 107114, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38190929

RESUMEN

BACKGROUND: Visceral leishmaniasis is a neglected tropical disease affecting millions of people worldwide. Macrophages serve as the primary host cells for L. donovani, the immune response capability of these host cells is crucial for parasites' intracellular survival. L. donovani peptidyl-prolyl cis/trans isomerase Cyclophilin A (LdCypA) is a key protein for L. donovani intracellular proliferation, while the molecular mechanism conducive to intracellular survival of parasites remains elusive. METHODS: In this study, we generated a macrophage cell line overexpressing LdCyPA to investigate its role in controlling host immunity and promoting intracellular immune escape of L. donovani. RESULTS: It was discovered that the overexpression of the LdCyPA cell line regulated the host immune response following infection by downregulating the proportion of M1-type macrophages, promoting the secretion of the anti-inflammatory factor IL-4, and inhibiting the secretion of pro-inflammatory factors like IL-12, IFN-γ, TNF-α, and INOS. Transcriptome sequencing and mechanistic validation, meanwhile, demonstrated that cells overexpressing LdCyPA controlled the immune responses that followed infection by blocking the phosphorylation of P38 and JNK1/2 proteins in the MAPK signaling pathway and simultaneously increasing the phosphorylation of ERK proteins, which helped the L. donovani escape immune recognition. CONCLUSION: Our findings thus pave the way for the development of host-directed antiparasitic drugs by illuminating the pro-Leishmania survival mechanism of L. donovani cyclophilin A and exposing a novel immune escape strategy for L. donovani that targets host cellular immune regulation.


Asunto(s)
Leishmania donovani , Leishmaniasis Visceral , Parásitos , Humanos , Animales , Leishmania donovani/genética , Ciclofilina A , Leishmaniasis Visceral/parasitología , Macrófagos , Interleucina-12
3.
Curr Med Sci ; 43(6): 1116-1132, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38079053

RESUMEN

OBJECTIVE: Numerous schizophrenic patients are suffering from obesity primarily attributed to antipsychotic medication and poor dietary habits. This study investigated the progressive deterioration of olanzapine-induced metabolic disorders in the presence of a high-fat diet (HFD) and explored the involvement of endoplasmic reticulum (ER) stress. METHODS: Female Sprague-Dawley rats fed on a standard chow diet or HFD were treated with olanzapine (3 mg/kg/day) and the ER stress inhibitor 4-phenylbutyric acid (4-PBA, 1 and 0.5 g/kg/day) for 8 days. Changes in body weight, food intake, and plasma lipids were assessed. Hepatic fat accumulation was evaluated using oil red O staining. Western blotting and immunofluorescence assays were employed to examine the expression of ER stress markers, NOD-like receptor pyrin domain-containing protein 3 (NLRP3), and proopiomelanocortin (POMC) in the hypothalamus or liver. RESULTS: Compared to olanzapine alone, olanzapine+HFD induced greater weight gain, increased hyperlipidemia, and enhanced hepatic fat accumulation (P<0.05). Co-treatment with 4-PBA exhibited a dose-dependent inhibition of these effects (P<0.05). Further mechanistic investigations revealed that olanzapine alone activated ER stress, upregulated NLRP3 expression in the hypothalamus and liver, and downregulated hypothalamic POMC expression. The HFD exacerbated these effects by 50%-100%. Moreover, co-administration of 4-PBA dose-dependently attenuated the olanzapine+HFD-induced alterations in ER stress, NLRP3, and POMC expression in the hypothalamus and liver (P<0.05). CONCLUSION: HFD worsened olanzapine-induced weight gain and lipid metabolic disorders, possibly through ER stress-POMC and ER stress-NLRP3 signaling. ER stress inhibitors could be effective in preventing olanzapine+HFD-induced metabolic disorders.


Asunto(s)
Dieta Alta en Grasa , Enfermedades Metabólicas , Humanos , Ratas , Animales , Femenino , Olanzapina/efectos adversos , Dieta Alta en Grasa/efectos adversos , Proteína con Dominio Pirina 3 de la Familia NLR , Ratas Sprague-Dawley , Proopiomelanocortina , Aumento de Peso
4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(9): 1343-1349, 2023.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38044645

RESUMEN

OBJECTIVES: Depression is often accompanied by various degrees of cognitive decline, with a high incidence. Guidelines recommend medication combined with psychological therapy. Solution focused group therapy (SFGT) is a newer group psychotherapy technique. This study aims to explore the difference between SFGT combined with escitalopram and only use escitalopram in treating depression. METHODS: A total of 84 patients who met the diagnostic criteria of international classification of diseases-10 (ICD-10) were enrolled into the combined group (SFGT combined with escitalopram, n=42) and the control group (only escitalopram, n=42) for an 8-week treatment. Patients were measured with the 24-item Hamilton Depression Scale (HAMD-24) and the Cognitive Flexibility Inventory (CFI) at baseline (T0), week 4 (T1), and week 8 (T2), respectively. Differences in depressive symptoms and cognitive flexibility between the 2 groups were compared and analyzed. RESULTS: At T2, 8 patients were dislodged in the combined group and 10 in the control group. There was no difference in the subscales and total scores of HAMD-24 and CFI between the 2 groups at T0 (all P>0.05). At T1 and T2, compared with the control group, the total scores and anxiety somatization, cognitive impairment, delay, and a sense of despair subscales scores of HAMD-24 were lower, and the total scores and subscales scores of CFI in the combined group were higher (all P<0.05). CONCLUSIONS: SFGT combined with escitalopram is more effective than monotherapy for improving the anxiety somatization symptoms, cognitive impairment, retardation symptoms and despair symptoms, and increasing the cognitive flexibility.


Asunto(s)
Trastorno Depresivo , Psicoterapia de Grupo , Humanos , Citalopram/uso terapéutico , Citalopram/efectos adversos , Depresión/terapia , Escitalopram , Trastorno Depresivo/complicaciones , Trastorno Depresivo/terapia , Cognición , Resultado del Tratamiento
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(6): 1097-1104, 2023 Dec 18.
Artículo en Chino | MEDLINE | ID: mdl-38101795

RESUMEN

OBJECTIVE: To investigate whether the placement of absorbable collagen membrane increase the stability of alveolar ridge contour after guided bone regeneration (GBR) using buccal punch flap. METHODS: From June 2019 to June 2023, patients who underwent GBR using buccal punch flap simultaneously with a single implant placement in posterior region (from first premolar to second molar) were divided into coverage group, in which particular bone graft was covered by collagen membrane and non-coverage group. Cone beam CT (CBCT) was taken before surgery (T0), immediately after surgery (T1), and 3-7 months after surgery (T2), and the thickness of the buccal bone plate at different levels (0, 2, 4, and 6 mm) below the smooth-rough interface of the implant (BBT-0, -2, -4, -6) was mea-sured after superimposition of CBCT models using Mimics software. RESULTS: A total of 29 patients, including 15 patients in coverage group and 14 patients in non-coverage group, were investigated in this study. At T0, T1, and T2, there was no significant difference in BBT between the two groups (P>0.05). At T1, BBT-0 was (2.50±0.90) mm in the coverage group and (2.97±1.28) mm in the non-coverage group, with corresponding BBT-2 of (3.65±1.08) mm and (3.58±1.26) mm, respectively. At T2, BBT-0 was (1.22±0.55) mm in the coverage group and (1.70±0.97) mm in the non-coverage group, with corresponding BBT-2 of (2.32±0.94) mm and (2.57±1.26) mm, respectively. From T1 to T2, there were no statistically significant differences in the absolute values [(0.47±0.54)-(1.33±0.75) mm] and percentages [(10.04%±24.81%)-(48.43%±18.32%)] of BBT change between the two groups. The thickness of new bone formation in the buccal bone plate from T0 to T2 ranged from (1.27±1.09) mm to (2.75±2.15) mm with no statistical difference between the two groups at all levels. CONCLUSION: In the short term, the GBR using buccal punch flap with or without collagen membrane coverage can effectively repair the buccal implant bone defect. But collagen membrane coverage showed no additional benefit on alveolar ridge contour stability compared with non-membrane coverage.


Asunto(s)
Aumento de la Cresta Alveolar , Humanos , Estudios de Cohortes , Estudios Retrospectivos , Colágeno , Tomografía Computarizada de Haz Cónico , Regeneración Ósea , Implantación Dental Endoósea
6.
Chin J Dent Res ; 26(4): 227-233, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38126368

RESUMEN

OBJECTIVE: To radiographically evaluate the effect of intact periosteum in guided bone regeneration (GBR) for the treatment of peri-implant ridge defects in posterior region. METHODS: Twenty-eight patients who satisfied the criteria were included in this study. Buccal dehiscence defects were regenerated using demineralised bovine bone mineral (DBBM). Subjects were divided into two groups: the control group (conventional GBR, buccal trapezoidal flap and DBBM with collagen membrane coverage, n = 14) and the test group (modified GBR, buccal pouch and DBBM with collagen membrane coverage, n = 14). CBCT images obtained immediately after and 3 to 7 months following GBR were used to assess buccal bone thickness (BBT) at a level of 0, 2, 4 and 6 mm below the implant platform. RESULTS: Immediately after surgery, BBT at 0 mm and 2 mm below the implant platform presented a significant difference between the two groups (P < 0.05) with significantly thicker buccal bone in the control group in terms of BBT-0 (3.83 ± 1.01 mm) and BBT-2 (4.88 ± 1.15 mm) than in the test group (2.33 ± 0.66 mm and 3.60 ± 1.10 mm, P = 0.000 and P = 0.008, respectively). After 3 to 7 months of healing, the BBT at all levels showed no significant difference between the two groups (P > 0.05), but more bone graft resorption (BBR) in the control group in terms of BBR-0 (2.45 ± 1.14 mm), BBR-2 (2.09 ± 0.94 mm) and BBR-0% (65.37% ± 26.62%) than the test group (BBR-0 1.07 ± 0.51 mm, P = 0.001; BBR-2, 1.22 ± 0.63 mm, P = 0.008; BBR-0% 45.70% ± 15.52%, P = 0.024). CONCLUSION: In the short term, all treatment modalities achieved similar coronal BBT and the intact periosteum had a positive effect on keeping ridge dimensions even.


Asunto(s)
Aumento de la Cresta Alveolar , Resorción Ósea , Implantes Dentales , Humanos , Animales , Bovinos , Implantación Dental Endoósea/métodos , Estudios de Cohortes , Estudios Retrospectivos , Periostio/cirugía , Aumento de la Cresta Alveolar/métodos , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/cirugía , Regeneración Ósea , Colágeno , Resorción Ósea/cirugía
7.
Clin Implant Dent Relat Res ; 24(6): 792-800, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36181244

RESUMEN

AIM: To 3-dimensional radiographically assess the effect of titanium plate in guided bone regeneration (GBR) for the treatment of peri-implant ridge defects in esthetic zone. MATERIAL AND METHODS: Nineteen patients with buccal peri-implant defects in the maxillary esthetic zone were treated with GBR using xenograft, autogenous bone, and collagen membrane. Subjects were divided into two groups: control (conventional GBR, 10 patients with 16 implants) and test (GBR with an adjunctive titanium plate; nine patients with 15 implants). Cone-beam computed tomography (CBCT) images obtained immediately after and 5-7 months following GBR were used to assess buccal crestal bone level (BBL) and buccal bone thickness (BBT) at different implant levels. RESULTS: Thirty-one implants in 19 patients were evaluated. Titanium plate exposure occurred in three cases (33.33%) of the test group. After 5-7 months, the mean BBL was located 1.48 ± 0.71 mm coronal to the platform in the test group and 0.90 ± 3.03 mm coronal to the platform in the control group (p = 0.03). The mean over all BBT (BBT-M) was 4.16 ± 0.48 mm in the test group and 2.38 ± 0.97 mm in the control group (p < 0.01). More resorption occurred in the control group than in the test group regarding mean BBL (3.00 ± 3.11 mm vs. 0.78 ± 0.79 mm, respectively; p = 0.04), BBT-M change (1.87 ± 1.59 mm vs. 0.56 ± 0.33 mm, respectively; p = 0.02), and percentage change in BBT-M (40.69 ± 24.01% vs. 11.53 ± 5.86%, respectively; p < 0.01). CONCLUSION: In the short-term, titanium plate-enhanced GBR maintained ridge dimensions better than conventional GBR did.


Asunto(s)
Aumento de la Cresta Alveolar , Implantes Dentales , Humanos , Aumento de la Cresta Alveolar/métodos , Implantación Dental Endoósea/métodos , Titanio , Proyectos Piloto , Estudios Retrospectivos , Estética Dental , Regeneración Ósea , Regeneración Tisular Guiada Periodontal/métodos
8.
Clin Implant Dent Relat Res ; 24(4): 414-423, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35557025

RESUMEN

BACKGROUND: Implant placement in maxillary molar sites with severe height deficiency often requires multiple surgeries, which was time-consuming, invasive, and subject to serious postoperative complications. PURPOSE: To introduce and assess a three-in-one technique (extraction, alveolar ridge preservation [ARP], and sinus elevation) for augmenting deficiency maxillary molar alveolar ridges. MATERIAL AND METHODS: Fourteen patients with severe posterior maxillary ridge height deficiency underwent extraction, sinus elevation via an intrasocket window and ARP using sticky bone and then covered with acellular dermal matrix (ADM). Primary closure was intentionally not obtained. Cone-beam computed tomography and periapical radiography were used to measure dimensional ridge changes over time. Bone biopsies were taken at implant placement 7-21 months after surgery, which proceeded without additional grafting. Peri-implant soft tissue was assessed after 8-12 months of functional loading. RESULTS: Maxillary molar sites (13 first molars, 1 second molar) with a mean sinus floor height of 1.73 ± 0.86 mm and mean buccal plate thickness of 1.62 ± 1.15 mm were elevated and grafted. Immediately after surgery, the mean sinus floor height was 14.03 ± 1.97 mm and the alveolar thickness at virtual implant platform level was 12.99 ± 1.88 mm. After 5-9 months healing, those measurements decreased by 2.45 ± 1.73 mm (p = 0.000) and 3.88 ± 3.95 mm (p = 0.006), respectively. Healed ridges were composed of 18.74% ± 4.34% mean vital bone and 19.08% ± 9.10% mean residual graft. After 8-12 months of functional loading, the peri-implant tissue appeared healthy, and there was a mean marginal bone loss of 0.12 ± 0.11 mm. CONCLUSIONS: For maxillary first molar sites with severe sinus floor height deficiency, this minimally invasive three-in-one treatment allows for uncomplicated implant placement and short-term functional stability.


Asunto(s)
Elevación del Piso del Seno Maxilar , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/cirugía , Humanos , Seno Maxilar/cirugía , Diente Molar/cirugía , Proyectos Piloto , Elevación del Piso del Seno Maxilar/métodos
9.
J Oral Implantol ; 48(5): 386-390, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34412125

RESUMEN

The purpose of his study was to investigate the projected ridge-implant dimensions derived from virtual superimposition of implants on intact first molars mimicking immediate implantation in the mandible (Md1) and maxilla (Mx1) using cone-beam computed tomography (CBCT). The CBCT records of 41 patients (19 males and 22 females) with Md1 or Mx1 were collected. Ten-millimeter-long cylindrical implants with different diameters were virtually positioned at prosthetically ideal angles into interradicular septum using CBCT software. Radiographic alveolar ridge height (ARH), alveolar ridge width (ARW), gap distance, and vertical distance from the implant platform to the alveolar crest were measured. Twenty Mx1s (48.8%) and 21 Md1s (51.2%) were included. The mean ARH values were 7.13 ± 4.32 and 15.64 ± 1.80 mm for Mx1 and Md1, respectively; 87.8% of mesiobuccal sites had gap distance of >2 mm when 6-mm-diameter implants were used. Increasing implant diameter from 6 to 9 mm decreased the percentage of sites with ARW > 2 mm from 80.5% to 41.5% buccally and from 86.4% to 26.8% lingually. The mean vertical distance from the implant platform to the alveolar crest was 1.41 ± 1.09 mm buccally and 1.11 ± 1.10 mm lingually. Immediate implant placement of first molars, especially in the maxilla, requires stringent presurgical evaluation. Implants no wider than 6 mm placed into the interradicular septum may meet acceptable running room and alveolar plate thickness criteria if the jumping distance is grafted. Further clinical trials are needed to confirm these findings in this virtual study.


Asunto(s)
Implantes Dentales , Tomografía Computarizada de Haz Cónico Espiral , Masculino , Femenino , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Proceso Alveolar/diagnóstico por imagen , Diente Molar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos
10.
Int J Oral Maxillofac Implants ; 36(6): 1224-1234, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34919625

RESUMEN

PURPOSE: Untreated severely damaged molar sockets often complicate implant placement. This study evaluated membrane degradation, soft tissue healing, and alveolar crest dimensional changes after alveolar ridge preservation (ARP) in severely damaged molar sockets using a polylactic acid membrane (PLA) and xenograft without primary wound closure. MATERIALS AND METHODS: A total of 14 damaged molar sockets in 12 patients were grafted with deproteinized bovine bone mineral, which was covered with a PLA membrane without primary wound closure. Wound healing was evaluated at set times. Three sets of CBCT data taken before surgery, at 1 to 2 weeks, and at 6 to 12 months after surgery were reconstructed and superimposed to analyze dimensional changes of the alveolar crest with volumetric imaging software. RESULTS: Two weeks after ARP, no degradation of PLA membrane was present, and the xenograft had either no exfoliation (7 sites, 50%) or mild exfoliation (6 sites, 42.9%). One to 2 months following ARP, the membrane was partially degraded in 6 sites (42.9%) and completely degraded in 8 sites (57.1%). Nine sites (64.3%) presented with mild graft particle exfoliation, and four sites (28.6%) had granulation tissue covering the bone graft. All sites were fully covered by keratinized mucosa by 6 to 12 months. Compared with baseline measurements, the vertical bone graft height decreased by 2.2 ± 2.2 mm, and central alveolar ridge thickness measured at the level of the virtual implant platform decreased by 5.0 ± 5.1 mm after 6 to 12 months. CONCLUSION: The exposed PLA membrane maintains some barrier function for at least 3 to 4 weeks after ARP in severely damaged molar extraction sites. This technique allowed for implant placements without additional grafting. Future studies should include histologic assessment of the augmented bone and nongrafted control sockets.


Asunto(s)
Proceso Alveolar , Poliésteres , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/cirugía , Animales , Bovinos , Humanos , Diente Molar/diagnóstico por imagen , Diente Molar/cirugía
11.
Chin J Dent Res ; 24(4): 251-256, 2021 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-35029096

RESUMEN

OBJECTIVE: To assess bone volume stability and identify critical bone graft thickness for guided bone regeneration (GBR) simultaneous to implant placement in the maxillary anterior region. METHODS: Eighteen patients were included in the study and received placement of one maxillary anterior implant combined with GBR using deproteinised bovine bone mineral (DBBM) and resorbable collagen membrane. The multilevel buccal bone thickness (BT) was measured by CBCT 1 to 2 weeks and 5 to 8 months post-implantation (at implant uncovering surgery). RESULTS: Significant buccal alveolar crest collapse (ACCb 1.20 to 1.70 mm) occurred during the mean healing period of 5.3 months (P = 0.000). A greater percentage of ACCb occurred at the coronal aspect of the implant, with 59.24% ± 19.22% at the implant platform and 34.10% ± 30.50% 6.0 mm below the implant platform, respectively. Linear regression analysis demonstrated that if BT was 1.8 to 2.0 mm at the implant platform at uncovering surgery, then it was estimated to have been 4.1 to 4.5 mm immediately post-implantation. CONCLUSION: ACCb after maxillary anterior implant placement with simultaneous GBR occurred more coronally than apically. Excessive alveolar ridge augmentation, up to 4.0 mm of hard tissue buccal to the implant platform, should be achieved at the time of surgery to compensate for this potential resorption.


Asunto(s)
Aumento de la Cresta Alveolar , Implantes Dentales , Animales , Regeneración Ósea , Bovinos , Implantación Dental Endoósea , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía
12.
Data Brief ; 20: 1587-1601, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30258964

RESUMEN

The data in this article contains major, trace and rare earth element concentrations of apatite, and statistic analysis of apatite morphology in the granitoid rocks from the Edong ore district, South China, together with zircon U-Pb dating results for these rocks. Both the ore-associated and barren granitoids yield similar ages, including quartz diorite in the Fuzishan Cu-Au skarn deposit (138.6 ± 2.9 Ma), quartz monzodiorite in the Niutoushan Cu skarn deposit (137.8 ± 1.8 Ma), quartz diorite in the Ouyangshan Cu skarn deposit (138.4 ± 1.2 Ma), Liujiawan quartz monzodiorite (135.0 ± 2.4 Ma), and Bengqiaodi quartz monzodiorite porphyry (138.7 ± 1.1 Ma). Apatite occurs in all the minerals for each rock sample, and a detailed petrographic analysis shows the majority of them are early formed mineral phase. The F, Cl, SO3 contents in apatite are different, those in ore-associated rocks show higher values than barren ones. Li, Ni, Co, V contents are also higher in apatites from the ore-associated rocks than in barren rocks. Apatite (La/Sm)N and (Yb/Sm)N ratio show a positive correlation for ore-associated rocks but a negative correlation for barren rocks.

13.
Anal Chem ; 89(24): 13415-13421, 2017 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-29120609

RESUMEN

Carbon isotopes have been widely used in tracing a wide variety of geological and environmental processes. The carbon isotope composition of bulk rocks and minerals was conventionally analyzed by isotope ratio mass spectrometry (IRMS), and, more recently, secondary ionization mass spectrometry (SIMS) has been widely used to determine carbon isotope composition of carbon-bearing solid materials with good spatial resolution. Here, we present a new method that couples a RESOlution S155 193 nm laser ablation system with a Nu Plasma II MC-ICP-MS, with the aim of measuring carbon isotopes in situ in carbonate minerals (i.e., calcite and aragonite). Under routine operating conditions for δ13C analysis, instrumental bias generally drifts by 0.8‰-2.0‰ in a typical analytical session of 2-3 h. Using a magmatic calcite as the standard, the carbon isotopic composition was determined for a suite of calcite samples with δ13C values in the range of -6.94‰ to 1.48‰. The obtained δ13C data are comparable to IRMS values. The combined standard uncertainty for magmatic calcite is <0.3‰ (1s). No significant matrix effects have been identified in calcite with the amplitude of chemical composition variation (i.e., MnO, SrO, MgO, or FeO) up to 2.5 wt %. Two modern corals were investigated using magmatic calcite as the calibration standard, and the average δ13C values for both corals are similar to the bulk IRMS values. Moreover, coral exhibits significant heterogeneity in carbon isotope compositions, with differences up to 4.85‰ within an individual coral. This study indicates that LA-MC-ICP-MS can serve as an appropriate method to analyze carbon isotopes of carbonate minerals in situ.


Asunto(s)
Carbonato de Calcio/análisis , Isótopos de Carbono , Terapia por Láser , Espectrometría de Masas
14.
J Periodontol ; 88(6): 550-564, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28168901

RESUMEN

BACKGROUND: This systematic review and meta-analysis aims to investigate survival rates of dental implants placed simultaneously with graft-free maxillary sinus floor elevation (GFSFE). Factors influencing amount of vertical bone gain (VBG), protruded implant length (PIL) in sinus at follow-up (PILf), and peri-implant marginal bone loss (MBL) are also evaluated. METHODS: Electronic and manual searches for human clinical studies on simultaneous implant placement and GFSFE using the lateral window or transcrestal approach, published in the English language from January 1976 to March 2016, were conducted. The random-effects model and mixed-effect meta-regression were used to analyze weighted mean values of clinical parameters and evaluate factors that influenced amount of VBG. RESULTS: Of 740 studies, 22 clinical studies were included in this systematic review. A total of 864 implants were placed simultaneously with GFSFE at edentulous sites having mean residual bone height of 5.7 ± 1.7 mm. Mean implant survival rate (ISR) was 97.9% ± 0.02% (range: 93.5% to 100%). Weighted mean MBL was 0.91 ± 0.11 mm, and it was significantly associated with the postoperative follow-up period (r = 0.02; R2 = 43.75%). Weighted mean VBG was 3.8 ± 0.34 mm, and this parameter was affected significantly by surgical approach, implant length, and PIL immediately after surgery (PILi) (r = 2.82, 0.57, 0.80; R2 = 19.10%, 39.27%, 83.92%, respectively). Weighted mean PILf was 1.26 ± 0.33 mm (range: 0.3 to 2.1 mm). CONCLUSION: Within limitations of the present systematic review, GFSFE with simultaneous implant placement can achieve satisfactory mean ISR of 97.9% ± 0.02%.


Asunto(s)
Seno Maxilar , Elevación del Piso del Seno Maxilar , Humanos , Pérdida de Hueso Alveolar , Bases de Datos Factuales , Implantación Dental Endoósea , Implantes Dentales , Fracaso de la Restauración Dental , Maxilar/cirugía , Seno Maxilar/anatomía & histología , Seno Maxilar/cirugía , Michigan
15.
Stem Cells ; 33(2): 615-21, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25263397

RESUMEN

Mesenchymal stem cells (MSCs) are multipotential stem cells residing in the bone marrow. Several studies have shown that mechanical stimulation modulates MSC differentiation through mobilization of second messengers, but the mechanism of mechanotransduction remains poorly understood. In this study, using fluorescence and laser confocal microcopy as well as patch-clamp techniques, we identified the transient receptor potential melastatin type 7 (TRPM7) channel as the key channel involved in mechanotransduction in bone marrow MSCs. TRPM7 knockdown completely abolished the pressure-induced cytosolic Ca(2+) increase and pressure-induced osteogenesis. TRPM7 directly sensed membrane tension, independent of the cytoplasm and the integrity of cytoskeleton. Ca(2+) influx through TRPM7 further triggered Ca(2+) release from the inositol trisphosphate receptor type 2 on the endoplasmic reticulum and promoted NFATc1 nuclear localization and osteogenesis. These results identified a central role of TRPM7 in MSC mechanical stimulation-induced osteogenesis.


Asunto(s)
Células de la Médula Ósea/metabolismo , Mecanotransducción Celular/fisiología , Células Madre Mesenquimatosas/metabolismo , Osteogénesis , Presión , Proteínas Serina-Treonina Quinasas/metabolismo , Canales Catiónicos TRPM/metabolismo , Células de la Médula Ósea/citología , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/citología
16.
J Agric Food Chem ; 62(49): 11840-53, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25404505

RESUMEN

Combined with high-performance liquid chromatography (HPLC) and linear-ion trap/Orbitrap high-resolution mass spectrometry, trypsin-catalyzed (16)O-to-(18)O exchange was used to establish an accurate quantitative method for bovine or porcine gelatin. The sophisticated modifications for these two mammalian gelatins were unambiguously identified by accurate mass and tandem mass spectrometry. Eighteen marker peptides were successfully identified for the bovine and porcine gelatin, respectively. The gelatins were subjected to (18)O or (16)O labeling in the presence of trypsin and mixed together in various ratios for quantification. All of the (18)O-labeled peptides were also confirmed by accurate mass and tandem mass spectrometry. The 10 marker peptides with the strongest signals were chosen to calculate the average ratios of (18)O-labeled and (16)O-labeled gelatin. The measured ratios of (18)O-labeled and (16)O-labeled peptides were very close to the mixing ratios of 20:1, 5:1, 1:1, and 1:5 with low standard deviation values. The samples with a mixing ratio of 1:1 (18)O-labeled and (16)O-labeled peptides were determined to 1.00 and 0.99 with standard deviations of 0.02 and 0.04 for bovine and porcine gelatins, respectively, indicating the high accuracy of this method. Trypsin-catalyzed (18)O labeling was proved to be an excellent internal calibrant for gelatins. When combined with HPLC and high-resolution mass spectrometry, it is an accurate and sensitive quantitative method for gelatin in the food industry.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Gelatina/química , Marcaje Isotópico/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Bovinos , Isótopos de Oxígeno/química , Porcinos
17.
Appl Opt ; 52(19): 4631-9, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23842261

RESUMEN

A theoretical analysis of fiber Bragg grating (FBG)-based plane strain monitoring of aerostat envelope structures is presented. Plane strain analysis of FBG-based aerostat envelope structures is much more complex than the case along the axis of the optical fiber because the effect of transverse stress on the FBG should be taken into consideration. To achieve accurate strain measurement of the aerostat envelope, a theoretical model is set up by using two perpendicular fibers in the monitoring. An analytical formula that evaluates the relationship between the strain measured by FBG sensors and the real one in the aerostat envelope is established. On the other hand, the real strain of aerostat envelope strain is affected by two unknown parameters, axial transfer rate K(L) and the radial transfer rate K(R). An equation is derived to calculate the axial transfer rate K(L). Then, the finite element method results show that K(R) is a very small value, but it cannot be ignored in accurate measurement. This paper would lay a theoretical groundwork for the research and design of FBG sensors in the structural health monitoring of aerostat envelope structures.

18.
Med Hypotheses ; 78(2): 273-6, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22115694

RESUMEN

The traumatic temporomandibular joint (TMJ) bony ankylosis has generated great interest in the cranio-maxillofacial surgeons yet remains an enigma, due to its unknown pathogenesis. Organization and ossification of hematoma is the classical hypothesis concerning the underlying pathophysiology, but it could not explain all the unique characters of TMJ bony ankylosis. The previous imaging descriptions about bony ankylosis tend to over-emphasize the obliteration of joint space and the overgrowth of new bone around the joint. Our recent study has found that the radiolucent zone in the bony fusion area indicating impaired bone healing is one of the most important imaging features of bony ankylosis, and this imaging feature is similar to that of hypertrophic nonunion of long bone. We also observe that there is close relationship between the mouth opening and the degree of calcification of radiolucent zone. Therefore, we hypothesize that the development of traumatic TMJ bony ankylosis may be the course of bone healing of two injured articular surfaces under the interference of opening movement, which is similar to the hypertrophic nonunion. Our hypothesis could help to explain some unintelligible characters of bony ankylosis, and deserves further studies.


Asunto(s)
Anquilosis/fisiopatología , Trastornos de la Articulación Temporomandibular/fisiopatología , Articulación Temporomandibular/fisiopatología , Animales , Huesos/patología , Calcinosis , Modelos Animales de Enfermedad , Humanos , Células Madre Mesenquimatosas/citología , Radiografía , Ovinos , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/etiología
19.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 45(1): 2-5, 2010 Jan.
Artículo en Chino | MEDLINE | ID: mdl-20368031

RESUMEN

OBJECTIVE: To investigate the relationship between fractured fragment and joint disc displacement after sagittal fracture of mandibular condyle (SFMC). METHODS: based on CT examination, SFMC were classified into fissue, displacement and dislocation type. Based on oblique sagittal MRI examination, the displacement of joint disc was grouped into type A and type B. Abnormal superiorposterior attachment was classified into elongation and avulsion type. RESULTS: CT exmination were taken in 26 patients with 41 SFMC. There were 5 SFMC (12%) with fissue type, 18 SFMC (44%) with displacement type and 18 SFMC (44%) with dislocation type. Both CT and MRI examination were taken in 19 patients with 32 SFMC. There were 27 (84%) SFMC with disc displacement. Five SFMC with type fissue showed no signs of disc displacement. Among 15 SFMC with type displacement, there were 3 cases with type A disc displacement and 12 cases with type B disc displacement. All the dislocated SFMC (12 cases) were type B disc displacement. In term of superiorposterior attachment figures, 4 cases (4/5) of type fissue SFMC showed normal. 14 cases (14/15) of the displacement SFMC showed elongated and all cases with dislocated SFMC showed sign of avulsion. There were 20 cases (63%) showing superior joint effusion. There were 13 cases (13/15) with displaced SFMC and 6 cases with dislocated SFMC showing joint effusion. One case with fissue SFMC showed no sign of joint effusion. CONCLUSIONS: Joint effusion, disc displacement and abnormal superiorposterior attachment were related to the displacement of condyle which was involved with SFMC.


Asunto(s)
Cóndilo Mandibular/lesiones , Fracturas Mandibulares/diagnóstico por imagen , Fracturas Mandibulares/diagnóstico , Disco de la Articulación Temporomandibular/patología , Trastornos de la Articulación Temporomandibular/etiología , Adolescente , Adulto , Niño , Femenino , Humanos , Luxaciones Articulares/etiología , Imagen por Resonancia Magnética , Masculino , Fracturas Mandibulares/clasificación , Persona de Mediana Edad , Trastornos de la Articulación Temporomandibular/diagnóstico , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto Joven
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 41(7): 388-90, 2006 Jul.
Artículo en Chino | MEDLINE | ID: mdl-17067450

RESUMEN

OBJECTIVE: To systematically evaluate the surgical and non-surgical treatment of condylar fracture using Meta-analysis system. METHODS: The key words: mandible, condyle, fracture and treatment/therapy were adopted to search for the objective articles from following Data-base: Medline, Embase, CCTR and CNKI. The available data were statistically dealt with by software package (RevMan 4.1). RESULTS: In 172 associated articles, only 10 (5.8%) fulfilled the entrance criteria, involving 711 cases. A total of 307 patients underwent surgical treatment due to severely displacement or dislocation of fragment, 239 of the m (78.0%) being subcondylar fracture. A total of 404 patients received non-surgical management, 278 of them (68.7%) being lower level fracture without significant displacement. Surgical treatment outbalanced non-surgical approach in rehabilitation of occlusional relationship and an adverse outcome was noted in term of maximum mouth opening, but the re was no significant difference in postoperative joint pain. CONCLUSIONS: Severely displaced and dislocated condylar fracture is indicated for surgical treatment.


Asunto(s)
Cóndilo Mandibular/lesiones , Fracturas Mandibulares/terapia , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Cóndilo Mandibular/cirugía , Fracturas Mandibulares/cirugía , Ensayos Clínicos Controlados Aleatorios como Asunto
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