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101.
The interplay between hematopoietic stem and progenitor cells (HSPC) and their local microenvironment is a key mechanism for the organization of hematopoiesis. To quantitatively study this process, a time-resolved analysis of cellular dynamics at the single-cell level is an essential prerequisite. One way to generate sufficient amounts of appropriate data is automatic single-cell tracking using time-lapse video microscopy. We describe and apply newly developed computational algorithms that allow for an automated generation of high-content data of single-cell characteristics at high temporal and spatial resolution, together with the reconstruction and statistical evaluation of complete genealogical histories. This methodology has been applied to the particular example of purified primary human HSPCs in bioengineered culture conditions. The combination of genealogical information and dynamic profiles of cellular properties identified a marked symmetry between sibling HSPCs regarding cell cycle time, but also migration speed and growth kinetics. Furthermore, we demonstrate that this symmetry of HSPC siblings can be altered by exogenous cues of the local biomimetic microenvironment. Using the example of HSPC growth in biomimetic culture systems, we show that our approach provides a valuable tool for the quantitative analysis of dynamic single-cell features under defined in?vitro conditions, allowing for integration of functional and genealogical data. The efficiency and accuracy of our approach pave the way for new and intriguing insights into the organizational principles of developmental patterns and the respective influence of exogenous cues not limited to the study of primary HSPCs.  相似文献   
102.
Objective. Depression with psychotic features is a severe subtype of major depression associated with the presence of delusions, hallucinations and specific neurobiological features. Despite clinical consensus and guideline recommendations, data comparing the efficacy of combining antipsychotics with antidepressants compared to antidepressants alone remain inconclusive. The aim of the study was to investigate effectiveness and tolerability of the atypical antipsychotic olanzapine in acute depression with psychotic features. Methods. Seventeen inpatients with major depressive disorder with psychosis (MDDp) were treated with a combination of an antidepressant and olanzapine for 6 weeks in a prospective open-label study. Depressive and psychotic symptoms, extrapyramidal and general side effects were assessed every 2 weeks. Sixteen patients were eligible for final analysis. Results. The Brief Psychiatric Rating Scale (BPRS) showed a 30% symptom reduction after week 2, a 45% symptom reduction after week 4 and no considerable improvement thereafter. Depressive symptoms (Bech–Rafaelsen Melancholia Scale, BRMS) receded by 37% after week 2 and 50% after week 4. No extrapyramidal side effects occurred. Conclusion. Olanzapine is effective and tolerable in combination with an antidepressant in an MDDp inpatient sample. The results concur with data supporting good efficacy in negative and depressive symptoms of patients with schizophrenic and schizoaffective diseases.  相似文献   
103.
The impact of paternal care on the development of catecholaminergic fiber innervations in the prefrontal cortex, nucleus accumbens, hippocampus and the amygdala was quantitatively investigated in the biparental Octodon degus. Two age (juvenile, adult) and rearing groups: (1) degus reared without father and (2) degus raised by both parents were compared. Juvenile father-deprived animals showed significantly elevated densities of TH-immunoreactive fibers in all analyzed regions, except in the orbitofrontal cortex, as compared to biparentally reared animals. This difference between the two rearing groups was still evident in adulthood in the prelimbic and infralimbic cortices and in the hippocampal formation. Interestingly, the elevated TH fiber density in both nucleus accumbens subregions was reversed in adulthood, i.e. adult father-deprived animals showed strongly reduced TH fiber densities as compared to biparentally reared animals. We show here that paternal care plays a critical role in the functional maturation of catecholaminergic innervation patterns in prefrontal and limbic brain circuits.  相似文献   
104.
Speech adaptation after oral rehabilitation is based on a complex interaction of articulatory and myofunctional factors. The knowledge of basic phonetic principles may help clinicians identify phonetic problems associated with prosthodontic treatment. The purpose of this article is to illustrate basic phonetic terminology, standard Chinese (Putonghua) phonetics, and the anatomic structures relevant for dentistry. In cooperation with a Chinese linguistic specialist, Chinese articulators were selected and are described and compared with English phonetics. Established test words and sentences aid the identification of mispronounced articulators and their related dental structures. The pronunciation of most consonants and vowels in standard Chinese is similar to English, but some of them, such as the retropalatals (/zh/ [t?], /ch/ [th?], /sh/ [?]), have notable differences. Palatal consonants (/j/ [t?], /q/ [t?h], /x/ [?]) are unique to the Chinese phonetic system and are not found in English phonetics. The comprehension of the basic anatomic regions involved in Chinese phonetics may help prosthodontists treat patients whose native language is standard Chinese.  相似文献   
105.
106.
This study aims to evaluate whether optical coherence tomography (OCT) using both the surface and the endoluminal technique is feasible to investigate the locations and degree of encrustation process in clinically used ureteral stents. After removal from patients, 14 polyurethane JJ stents were investigated. A fresh JJ served as a control. The external surfaces were examined using an endoscopic surface OCT whereas the intraluminal surfaces were investigated by an endoluminal radial OCT device. The focus was on detection of encrustation or crystalline sedimentation. In 12 female and two male patients, the median indwelling time of the ureteral catheter was 100 days (range, 19–217). Using the endoluminal OCT, the size and grade of intraluminal encrustation could be expressed as a percentage relating to the open lumen of the reference stent. The maximum encrustation observed resulted in a remaining unrestricted lumen of 15–35 % compared to the reference. The luminal reduction caused by encrustation was significantly higher at the proximal end of the ureteral stent as compared to its distal part. The extraluminal OCT investigations facilitated the characterization of extraluminal encrustation. OCT techniques were feasible and facilitated the detection of encrustation of double pigtail catheters on both the extra and intra luminal surface. Quantitative expression of the degree of intraluminal encrustation could be achieved, with the most dense and thickened occurrence of intraluminal incrustation in the upper curl of the JJ stent.  相似文献   
107.
Treatment of relapsed or refractory multiple myeloma remains a challenge and novel treatment regimen are required. Here, a matched pair analysis was performed comparing TCID (thalidomide, cyclophosphamide, idarubicin, dexamethasone) treatment to the treatment of patients with VID (vincristine, idarubicin, dexamethasone) or with VRID (vinorelbine, idarubicin, dexamethasone) for relapsed or refractory multiple myeloma. In total, 197 patients were enrolled in multicenter trials. After matching for important prognostic variables 46 matched-pairs (total of 138 patients) could be analysed with regard to survival, toxicity and efficacy. Interestingly, a significant improvement of overall response rate (ORR) for TCID treatment compared to VID and VRID was found. In addition, TCID treatment also led to a significantly higher overall survival (OS) as well as progression-free survival (PFS) compared to VID and VRID. In conclusion, TCID treatment appears to be superior to VRID and VID treatment in patients with progressive or refractory myeloma.  相似文献   
108.
NK cell function is important in the immune response to HIV infection. NKG2C and NKG2A are activating and inhibitory NK cell receptors, respectively, and their only known ligand, HLA-E, demonstrates increased expression in HIV infection and presents at least one HIV-derived peptide. A variation in chromosome 12 exists in which the 16-kb section of DNA encompassing the nkg2c gene is completely absent. DNA samples of 433 HIV-1-infected patients and 280 controls were genotyped by PCR, and revealed an association of the absence variation with a higher risk of HIV infection, as well as faster progression and higher pretreatment viral loads (p<0.05, respectively). Surface NKG2C expression, analyzed by FACS, on the freshly isolated lymphocytes of 20 control and 19 HIV-infected donors revealed that NKG2C expression is genotype dependent in both populations: no NKG2C expression in the -/- groups, intermediate expression in the +/- groups, and highest expression in the +/+ groups. The comparison of NKG2C and NKG2A expression in HIV and control groups (+/- and +/+ included) indicates an increased NKG2C expression on HIV patient NK cells (p<0.05) and decreased inhibitory NKG2A expression on CD8 T cells (p<0.001), and both these effects are more striking in the +/+ genotype (p<0.005). Furthermore, a positive correlation was found between HIV viral load and the proportion of NKG2C(+) NK cells. The increased expression of NKG2C in HIV patients, in combination with the genetic association of the absence variation with an increased susceptibility to HIV infection, higher HIV viral set point, and a faster progression, indicate that NKG2C is important in the defense against HIV infection and progression.  相似文献   
109.
The nature and determinants of the placebo response are widely unknown, as are the underlying psychological and biological mechanisms. Placebo response rates in functional bowel disorders (functional dyspepsia, irritable bowel syndrome) trials are similar to those in nonintestinal pain conditions and are comparable with other organic gastrointestinal diseases (duodenal ulcer, inflammatory bowel diseases). In this narrative review, different methodologies (meta-analyses, reanalyses, and experimental setups) are discussed that have been applied to the study of the placebo response in functional dyspepsia and the irritable bowel syndrome.  相似文献   
110.
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