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The environments that harbor hematopoietic stem and progenitor cells are critical to explore for a better understanding of hematopoiesis during health and disease. These compartments often are inaccessible for controlled and rapid experimentation, thus limiting studies to the evaluation of conventional cell culture and transgenic animal models. Here we describe the manufacture and image-guided monitoring of an engineered microenvironment with user-defined properties that recruits hematopoietic progenitors into the implant. Using intravital imaging and fluorescence molecular tomography, we show in real time that the cell homing and retention process is efficient and durable for short- and long-term engraftment studies. Our results indicate that bone marrow stromal cells, precoated on the implant, accelerate the formation of new sinusoidal blood vessels with vascular integrity at the microcapillary level that enhances the recruitment hematopoietic progenitor cells to the site. This implantable construct can serve as a tool enabling the study of hematopoiesis.  相似文献   
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ObjectivesBee-Humming Breathing (BHB) exercise is a simple yogic practice recommended for its favorable effect on cardiac physiology, including blood pressure (BP) and autonomic nervous system. However, strong evidence supporting its effectiveness is lacking. The present study was designed to evaluate the immediate effect of BHB exercise on blood pressure parameters and heart rate variability (HRV) in patients with essential hypertension.Study methodsWe conducted a randomized control trial including 70 patients with essential hypertension, randomly allocated to perform either BHB exercise (n=35) or placebo slow breathing exercise (n = 35) for 5-minutes duration. Blood pressure and HRV were measured before, during, and after the practice.ResultsThere was no significant decrease in systolic [effect size (95% CI): 2.22 (-13.20, 17.64); p 0.77], diastolic [4.54 (-17.40, 26.48); p 0.68] and mean blood pressures [1.37 (-8.78, 11.52); p 0.78] after BHB exercise in comparison to the control group in our study. The HRV analysis showed a significant increase in the HF power [6.8 (1.47, 12.12); p 0.01], and decrease in the LF power [?26.47 (?34.25, ?18.68); p < 0.01] during the recovery phase of the 5-minute BHB exercise in comparison to the control group.ConclusionsThis is the first randomized controlled trial to show that though a single short session of BHB exercise in hypertensive patients does not significantly reduce BP, it significantly augments the parasympathetic tone as indicated by a significant improvement in HRV parameters.Clinical trial registration numberCTRI/2018/08/015215  相似文献   
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Background:

The pathogenesis of psoriasis is still to be fully unraveled. The immunological theory with T cells at the centre of attraction and peripherally acting cytokines are the present favourites among aetiopathological factors. Histopathology of the skin lesions offers a good study model to understand the pathogenesis of this complex disease.

Aims:

To study the various histopathological parameters of psoriatic lesions, and to establish their correlation with the pathogenesis of the disorder.

Materials and Methods:

Eighty eight consecutive histopathologically proven cases of psoriasis were included in the study. Eight common histopathological parameters of psoriasis present in these biopsies were assessed and graded. We then statistically analyzed the relationship of the factors with one another and attempted to establish a better understanding of the pathogenesis of disease.

Results:

Significant correlations were found between degree of epidermal hyperplasia and inflammatory infiltrate, grade of inflammation and pustules of Kogoj, inflammatory infiltrate and grade of capillary proliferation as also between epidermal hyperplasia and the presence of parakeratosis.

Conclusion:

The study suggests that the immunopathogenesis of psoriasis is predominantly based on the inflammatory response. This is in consonance with other studies which have suggested that psoriasis is primarily a T lymphocyte based disease. Several treatment modalities are now based on this concept and it is hoped that the future treatment modalities will focus on the central role of inflammatory cells in the pathogenesis of this enigmatic disease.  相似文献   
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One hundred ninety patients underwent 197 HLA-matched related allogeneic stem cell transplantation for a diagnosis of beta thalassemia major at our center. The median age (+/-SD) was 7+/-4.1 years, and there were 129 (68%) males. Age and liver size as continuous variables were significantly associated with an adverse outcome. Using a receiver operator characteristics curve plot analysis, cutoff values of 7 years and 5 cm for age and liver size, respectively, were associated with the highest likelihood ratio of an adverse impact. On a multivariate analysis age>or=7 years and liver size>or=5 cm had a significant impact on event free survival (EFS) (relative risk 2.2 and 2.7, P values .014 and .000, respectively). Using these 2 variables, patients were categorized as high risk if they were >or=7 years and had a liver size>or=5 cm (n=41; all belonged to Class III). The 5-year EFS and overall survival (OS) in this high-risk group was 23.93+/-6.88 and 39.01+/-7.96, whereas in the remaining Class III patients (n=64) it was 70.3+/-6.06 and 78.3+/-5.5, respectively. This risk stratification identifies a significant subset (39%) of patients among those in Class III who have a poor outcome with a conventional myeloablative allogeneic stem cell transplantation. Patients in this high-risk group would probably benefit from novel therapeutic approaches.  相似文献   
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PURPOSE: This study retrospectively evaluated individuals with traumatic injuries from different mechanisms and tried to determine if there is any relationship between various isolated or combined fractures of facial skeleton and cranial injuries. MATERIALS AND METHODS: We retrospectively studied hospital charts of all patients who reported to the trauma center at Kasturba Hospital in Manipal with facial fractures and suspected cranial injuries during a 5-year period (January 1, 1995 to December 31, 1999). These patients were admitted to the Department of Neurosurgery or the Maxillofacial Unit of Kasturba Hospital, Manipal. The complete medical record of each patient was reviewed, recording the following in a standard format: age, gender, cause of injury, type of facial fractures, type of cranial bone fracture, concussion, intracranial injury, cerebrospinal fluid (CSF) rhinorrhea, CSF otorrhea, and the Glasgow coma scale. RESULTS: The study data were collected as part of retrospective analysis. A total of 12,329 patients reported to the trauma center of the study hospital during a 5-year period with various injuries. A total of 772 patients had facial fractures (6%). A total of 108 patients with a combination of cranial injuries and facial fractures were identified within this group (14%). Gender predilection was seen to favor males (90%) more than females (10%). The ratio was seen to be nearly 9:1. The ages of the patients ranged from 7 to 70 years with mean age being 32 years (standard deviation [SD] = +/-12). Central midfacial bone involvement was found to be more commonly associated with head injury. CONCLUSIONS: There is a correlation between midfacial injuries and CNS trauma. A more exhaustive multicentric case-control study with a larger sample and additional parameters will be essential to reach definite conclusions regarding the spectrum of head injuries associated with facial fractures.  相似文献   
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