Pilot study of a novel vacuum-assisted method for decellularization of tracheae for clinical tissue engineering applications

Tissue engineered tracheae have been successfully implanted to treat a small number of patients on compassionate grounds. The treatment has not become mainstream due to the time taken to produce the scaffold and the resultant financial costs. We have developed a method for decellularization (DC) based on vacuum technology, which when combined with an enzyme/detergent protocol significantly reduces the time required to create clinically suitable scaffolds. We have applied this technology to prepare porcine tracheal scaffolds and compared the results to scaffolds produced under normal atmospheric pressures. The principal outcome measures were the reduction in time (9 days to prepare the scaffold) followed by a reduction in residual DNA levels (DC no-vac: 137.8±48.82 ng/mg vs. DC vac 36.83±18.45 ng/mg, p<0.05.). Our approach did not impact on the collagen or glycosaminoglycan content or on the biomechanical properties of the scaffolds. We applied the vacuum technology to human tracheae, which, when implanted in vivo showed no significant adverse immunological response. The addition of a vacuum to a conventional decellularization protocol significantly reduces production time, whilst providing a suitable scaffold. This increases clinical utility and lowers production costs. To our knowledge this is the first time that vacuum assisted decellularization has been explored. Copyright © 2015 John Wiley & Sons, Ltd.

Correlation between follicular diameters and flushing versus no flushing on oocyte maturity, fertilization rate and embryo quality

OBJECTIVE

To determine (a) the correlation between follicular sizes, oocyte maturity, normal fertilization rate, cleavage and embryo quality; and (b) to establish whether oocytes recovered with or without follicular flushing have different developmental competence.

DESIGN

Prospective observational study.

SETTING

Academic medical center.

PATIENTS

Forty nine cycles (37 ICSI and 12 IVF).

INTERVENTIONS

Measurement of 360 follicular diameters on the day of egg retrieval and classification into three groups Group A (mean diameter 12-14.5 mm.), group B (mean diameter 15-18 mm.) and group C (diameter >18.5 mm.).

MAIN OUTCOME MEASURE

Correlation between follicular size at the time of retrieval and oocyte maturity, fertilization and cleavage rate in 226 oocytes (163 ICSI and 63 IVF). Developmental competence of oocytes retrieved with flushing versus non flushing.

RESULTS

Almost all (99 %) of the oocytes recovered from follicles of group C were in metaphase II as opposed to 80 % in group A and 81 % in group B (p < 0.01). Overall there was a progressive and significant increase in fertilization rates from group A follicles to group C (47 % vs. 67 %, p 0.05). Overall 53 % of oocytes retrieved from group A follicles showed either no fertilization or abnormal fertilization versus 27 % in group C (p 0.05). The oocyte recovery rate with follicular flushing improved from group A to group B and to group C follicles (65 % vs. 49 % vs.37 % respectively p < 0.01). There were no differences in rates of immature oocyte, fertilization, abnormal or not fertilization and cleavage.

CONCLUSIONS

The results of this study shows that: a) Follicles larger than 18 mm at retrieval have consistently mature oocytes with a higher rate of fertilization; b) Small size follicles are still capable of containing mature oocytes, but their rate of abnormal or no fertilization is high; c) Oocytes recovered with flushing are still able to produce embryos with full developmental competence.

Heart stopper genes: would you recognize a high risk patient?

Coronary artery disease (CAD) is one of the leading causes of death in the United States. Eighty percent of people having heart attacks have normal cholesterol levels. A quarter of the population have a condition called low-density lipoprotein (LDL) pattern B that has been associated with a threefold risk of myocardial infarction. Although early intervention can often prevent an otherwise fatal event, these patients often go unrecognized until after a myocardial infarction has occurred because they may not have the usual risk factors associated with cardiovascular disease. In patients with LDL pattern B, the standard lipid panel may be normal and inadequate for diagnosis and treatment of the condition. This article discusses how to identify a potentially high risk patient, available laboratory tests, management options, and the role of nurses in identifying high risk patients. The second author tells his personal story of surviving multiple cardiac arrests at a young age before being diagnosed with this condition.

Development and testing of the symptom experience scale

The Symptom Experience Scale (SES) was designed to measure women's experience of symptoms associated with treatment for breast cancer. The SES, a modification of McCorkle's Symptom Distress Scale, was developed and tested in a sample of 252 women with breast cancer. Exploratory factor analysis yielded six factors, which used all 24 SES items and accounted for 83.2% of the variance. The factors were nausea and appetite, fatigue and sleep, concentration, appearance, bowel pattern, and pain. Cronbach's alpha internal consistency reliability coefficients ranged from 0.92 to 0.96; the alpha for the total SES was 0.94. Subscale to subscale correlations ranged from 0.21 to 0.56. Additional research is recommended with samples large enough to permit confirmatory factor analysis and determine the stability of the factor structure identified in the present study. Additional research also is recommended to determine the applicability of the SES for men and women of diverse ethnic groups with various types of cancer and other chronic illnesses.