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61.
Background: The aim of this study is to evaluate the effects of caffeine and/or estrogen deficiency on ligature‐induced bone loss (BL), trabecular bone area (TBA), and postextraction bone healing (BH). Methods: Rats were assigned into one of the following groups (15 each): 1) control = non‐ingestion of caffeine/sham surgery; 2) caffeine = ingestion of caffeine/sham surgery); 3) ovariectomized (OVX) = non‐ingestion of caffeine/ovariectomy; or 4) caffeine/OVX = ingestion of caffeine/ovariectomy. The rats were under caffeine administration for 65 days and/or estrogen deficiency for 51 days. On day 21 after ovariectomy, one first mandibular molar received a ligature and the contralateral tooth was not ligated. The first maxillary molars were extracted 8 days before sacrifice. BL, TBA, the positive cells for tartrate‐resistant acid phosphatase (TRAP), receptor activator of nuclear factor‐κB ligand (RANKL), and osteoprotegerin (OPG) were analyzed in the furcation area of mandibular molars. Histometric BH and gene expression of bone morphogenetic protein (BMP)‐2, BMP‐7, osteopontin, and bone sialoprotein were evaluated in alveolar sockets. Results: The caffeine group presented the greatest BL and the OVX group the highest number of TRAP‐positive (TRAP+) cells around ligated teeth (P <0.05). The control group presented higher TBA and BH than the other groups (P <0.05). All test groups presented higher RANKL/OPG+ cells than the control group around ligated/unligated teeth. The OVX and caffeine/OVX groups presented a greater number of TRAP+ cells around unligated teeth than the control group (P <0.05). There were no differences among groups for gene expression (P >0.05). Conclusions: Caffeine increased BL in ligated teeth. Caffeine and/or estrogen deficiency decreased TBA in the unligated teeth and reduced BH after tooth extraction.  相似文献   
62.
Lewis  Ariane 《Neurocritical care》2019,31(2):449-450
Neurocritical Care -  相似文献   
63.

Background

Three recent lawsuits that address declaration of brain death (BD) garnered significant media attention and threaten to limit physician power to declare BD.

Methods

We discuss these cases and their consequences including: the right to refuse an apnea test, accepted medical standards for declaration of BD, and the irreversibility of BD.

Results

These cases warrant discussion because they threaten to: limit physicians’ power to determine death; incite families to seek injunctions to continue organ support after BD; and force hospitals to dispense valuable resources to dead patients in lieu of patients with reparable illnesses or injuries.

Conclusions

Physicians, philosophers, religious officials, ethicists, and lawyers must work together to address these issues and educate both the public and medical community about BD.
  相似文献   
64.

Objective

To assess the expression and regulation of antilipoprotein D (ApoD) and antilipoprotein E (ApoE) in human endometrium.

Study design

Endometrial biopsies from healthy, regularly cycling women were collected during the late proliferative and mid-secretory phase. mRNA gene expression of ApoD and ApoE was determined using real-time PCR in whole tissue, in isolated stromal (ESC), epithelial (EEC) and CD45+ leukocytes (EIC), as well as after hormonal stimulation of ESC and EEC in vitro. Protein expression was analyzed using immunohistochemistry.

Results

ApoD and ApoE mRNA was expressed in all cell types examined. A rise in ApoD mRNA expression was seen in whole endometrium, ESC, and EEC in the secretory phase, as well as after hormonal stimulation of ESC and EEC in vitro. ApoE mRNA was significantly upregulated in whole endometrium of secretory phase biopsies, while its expression was not altered by progesterone in vitro. Immunohistochemistry of whole endometrial tissue localized ApoD mainly in ESC and EEC. While ApoE was localized slightly in ESC, it was particularly noted on the surface of secretory phase endothelial cells.

Conclusion

We demonstrate for the first time the cell-type and cycle dependent expression of ApoD and ApoE within human endometrium, suggesting their role in endometrial modulation.  相似文献   
65.
In the following paper we describe our experience with a large number of patients in which either a laparoscopic assisted procedure or a total laparoscopic operation was performed. From 1996 until 2005 a total number of 638 aortic patients were operated on using a total laparoscopic or a laparoscopic assisted approach. A total laparoscopic operation was accomplished in 236 cases. A laparoscopic assisted aortic operation was performed in 402 patients. In aneurysm patients a tube graft was more frequently implanted. Thirty-day mortality was significantly higher in patients with a total laparoscopic abdominal aortic aneurysm repair (3.0%) compared to a laparoscopic assisted procedure (1.8%). There was no significant difference in mortality in patients with occlusive disease and a total laparoscopic aortofemoral bypass versus a laparoscopically assisted operation. The same tendency could be observed when analyzing the incidence of major perioperative complications. Again we found no significant difference in patients with occlusive disease yet more severe complications directly related to the operation in patients with a total laparoscopic aneurysm repair. There was a significantly increased complication rate in total laparoscopic aortoiliac repair with a bifurcated prosthesis compared to a tube graft repair: a tendency we could not observe in aneurysm patients with a laparoscopic assisted operation. Our data also show that there is a lot of room for technical improvements such as stapling devices or special grafts to reduce total operating times as well as the period of aortic crossclamping. The routine use of a minilaparotomy can hardly be a solution considering the technical drawbacks such as impaired vision and long term complications like ventral hernias. Compared to open surgery the midterm results of laparoscopic aortic procedures are promising. The time has come to prove that good results can be obtained in more than a few specialized centers.  相似文献   
66.
ABSTRACT

The histological analysis of bone for forensic application requires thin sections to be prepared from extracted bone of suitable quality for visualization through conventional light microscopy and (if required) the measurement of microstructural features, such as osteons. While a number of protocols for the preparation of thin sections exist, they are often time consuming and complex, or require expensive and non-portable equipment. A revised protocol is presented for obtaining high quality thin sections for light microscopy and histological analyses, tested in fresh, fixed, and dry archaeological cortical bone. It does not require extensive experience, or expensive materials or equipment, and can be further adapted for use with manual tools if necessary.  相似文献   
67.

Objectives

To compare the image quality of CT with iterative reconstruction alone and in association with projection-based single-energy metal artifact reduction (SEMAR) for the visualization of specific periarticular soft tissue structures in patients with hip prostheses.

Methods

CT studies from 48 consecutive patients with a hip prosthesis (24 unilateral and 24 bilateral) were retrospectively reconstructed using two different methods: iterative reconstruction (IR) alone and IR associated with SEMAR. The influence of metallic artifacts on the identification of various periarticular structures was evaluated subjectively by two readers. The image quality was compared in patients with unilateral and bilateral prostheses.

Results

Visualization of periprosthetic soft tissue was significantly improved by the SEMAR algorithm (p?<?0.0001). When SEMAR was associated with IR, the gluteus minimus and medius tendons, obturator internus muscle, prostate/uterus and bladder could be seen with medium or high confidence. There were no significant differences in image quality between patients with unilateral or bilateral prosthesis when SEMAR was used (p?>?0.2). This algorithm increased the detection of periarticular masses by 30 %.

Conclusion

SEMAR significantly improves the image quality of periarticular soft-tissue structures in patients with hip prostheses.  相似文献   
68.
The adult brain contains niches of neural stem cells that continuously add new neurons to selected circuits throughout life. Two niches have been extensively studied in various mammalian species including humans, the subventricular zone of the lateral ventricles and the subgranular zone of the hippocampal dentate gyrus. Recently, studies conducted mainly in rodents have identified a third neurogenic niche in the adult hypothalamus. In order to evaluate whether a neural stem cell niche also exists in the adult hypothalamus in humans, we performed multiple immunofluorescence labeling to assess the expression of a panel of neural stem/progenitor cell (NPC) markers (Sox2, nestin, vimentin, GLAST, GFAP) in the human hypothalamus and compared them with the mouse, rat and a non‐human primate species, the gray mouse lemur (Microcebus murinus). Our results show that the adult human hypothalamus contains four distinct populations of cells that express the five NPC markers: (a) a ribbon of small stellate cells that lines the third ventricular wall behind a hypocellular gap, similar to that found along the lateral ventricles, (b) ependymal cells, (c) tanycytes, which line the floor of the third ventricle in the tuberal region, and (d) a population of small stellate cells in the suprachiasmatic nucleus. In the mouse, rat and mouse lemur hypothalamus, co‐expression of NPC markers is primarily restricted to tanycytes, and these species lack a ventricular ribbon. Our work thus identifies four cell populations with the antigenic profile of NPCs in the adult human hypothalamus, of which three appear specific to humans.  相似文献   
69.

Background and Purpose

The relationship between in-hospital hyperglycemia and neurological outcome after intracerebral hemorrhage (ICH) is not well studied.

Methods

We analyzed the relationships between pre-hospital and hospital variables including highest in-hospital glucose (HIHGLC) and discharge Glasgow Coma Scale (GCS), discharge Modified Rankin Scale (MRS) and 3-month MRS using a single-institution cohort of ICH patients between 2013 and 2015.

Results

There were 106 patients in our sample. Mean HIHGLC was 154 ± 58 mg/dL for patients with discharge GCS of 15 and 180 ± 57 mg/dL for patients with GCS < 15; 146 ± 55 mg/dL for patients with discharge MRS 0-3 and 175 ± 58 mg/dL for patients with discharge MRS 4-6; and 149 ± 52 mg/dL for patients with 3-month MRS of 0-3 and 166 ± 61 mg/dL for patients with 3-month MRS of 4-6. On univariate analysis, discharge GCS was associated with HIHGLC (P?=?.01), age (P?=?.006), ICH volume (P?=?.008), and length of stay (LOS) (P?=?.01); discharge MRS was associated with HIHGLC (P < .001), age (P < .001), premorbid MRS (P?=?.046), ICH volume (P < .001), and LOS (P < .001); and 3-month MRS was associated with HIHGLC (P?=?.006), discharge MRS (P < .001), age (P?=?.001), sex (P?=?.002), ICH volume (P?=?.03), and length of stay (P?=?.004). On multivariate analysis, discharge GCS only had a significant relationship with ICH volume (odds ratio [OR] .949, .927-.971); discharge MRS had a significant relationship with age (OR 1.043, 1.009-1.079), premorbid MRS (OR 2.622, 1.144-6.011), and ICH volume (OR 1.047, 1.003-1.093); and 3-month MRS only had a significant relationship with age (OR 1.039, 1.010-1.069).

Conclusions

The relationship between in-hospital hyperglycemia and neurological outcomes in ICH patients was meaningful on univariate, but not multivariate, analysis. Glucose control after ICH is important.  相似文献   
70.
The manganese-dependent superoxide dismutase (MnSOD) Ala16Val single nucleotide polymorphism (SNP) has shown to be associated to risk factors of vascular diseases. Brain-Derived Neurotrophic Factor (BDNF) plays an essential role in the plasticity and neuronal regeneration of the brain after vascular injuries. However, little is known about interaction between MnSOD Ala16Val SNP on stroke, a frequent neurologic disease that involves various interacting pathways, such as vascular dysfunctions, inflammation, and neurotrophic factors. In this sense, the objective of this study was to investigate the relationship between MnSOD Ala16Val SNP with BDNF levels on stroke and also its influence on nitrosative stress, inflammatory, apoptotic, and DNA damage parameters. For this, 88 subjects were investigated, 44 subjects poststroke and 44 healthy controls. Questionnaires were applied to clinical characteristics and after laboratorial exams were collected. We analyzed levels of oxidative/nitrosative stress, inflammatory, apoptotic, and DNA damage markers. We showed a higher proportion of VV genotype in poststroke as compared to healthy subjects. Nitrite/nitrate, Tumor Necrosis Factor-α, Caspase 3 (CASP 3) and 8 (CASP 8) activation, Acethylcholinesterase (AChE), and Picogreen levels were higher in VV poststroke group, as well as BDNF and ACh levels were lower in VV and AV poststroke. We may suggest that V allele carries a worse outcome profile after stroke, relating to nitrosative stress, inflammatory, and apoptotic response. These events associated to a BDNF reduction, probably, contribute to the appearance or reincidence of stroke.  相似文献   
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