Growth of vaccine strains of avian pneumovirus in different cell lines

The isolation of avian pneumovirus (APV) (avian metapneumovirus) is usually performed in embryonated chicken eggs or chicken embryo fibroblast cell cultures followed by adaptation in continuous cell lines such as Vero cells. This study was conducted to find a suitable cell line that could be used to propagate vaccine strains of APV to high titre. For this purpose, we compared the growth of two Vero cell-adapted vaccine strains of APV (P63 and ca-APV) in seven different cell types with their growth in Vero cells. The cell types used were BGM-70, MA-104, QT-35, BHK-21, McCoy and DF-1 cells and primary turkey embryo fibroblast cells. When compared with growth in Vero cells, both viruses yielded higher titres in BGM-70 cells, while P63 also produced higher titres in MA-104 cells. In another experiment, the two viruses were grown and titrated in Vero cells under various cell culture conditions, such as age of cells, seeding concentration, and time of harvest. None of these cell culture variables were found to affect virus titres.

Novel methods of forming self-assembled nanostructured materials: Ni nanodots in Al2O3 and TiN matrices

We have developed two novel methods of growing self-assembled nanodot arrays of uniform size (diameter 2-50 nm) of a variety of materials in crystalline as well as amorphous matrices. These methods employ a pulsed laser deposition technique and are classified as: (a) sequential growth method; and (b) simultaneous growth method. In the first method, the nanodots and matrix material are formed sequentially, while in the second method, nanodots and matrix materials grow simultaneously. In the sequential growth, self-assembly of nanodots is controlled by the flux of materials, interfacial energy, intervening matrix layer, substrate and laser parameters. For the simultaneous growth method of self-assembly of nanodots, there is additional requirement that the material of the nanodot and the matrix should be such that the Gibb's free energy of oxidation of the constituent of matrix material is much lower than that of the nanodot material.

Magnetic beads (Dynabead) toxicity to endothelial cells at high bead concentration: implication for tissue engineering of vascular prosthesis

Magnetic beads (Dynabeads) have been used for the purification of endothelial cells. One application for this procedure may be for single-stage seeding of bypass grafts. The number of endothelial cells (EC) isolated is crucial and therefore to increase the number of cells extracted, a higher number of Dynabeads per cell may need to be used. The effect of large numbers of CD31 Dynabeads on cell proliferation/metabolism is unknown. We undertook this study using CD31-coated Dynabeads and EC from human umbilical vein. EC were coated at concentrations of 4, 10, or 50 beads per cell. The cells were cultured for 6 days with control being normal EC. Cellular proliferation was assessed by trypsinization of cells and metabolism assessed with an Alamar blue viability assay. In a further experiment a compliant polyurethane graft was single-stage seeded with both coated Dynabeads and normal EC. The results showed that using a higher number of beads per cell resulted in a reduction in cell proliferation and a reduction in cell metabolism. The total number of Dynabeads-coated cells in culture compared to controls (%) by day 6 were 30.7 +/- 2.56, 41.3 +/- 9.8 and 59.2 +/- 7.3 for 50, 10, and 4 beads per cell, respectively. The corresponding results for Alamar blue were 43.7 +/- 1.2, 61.8 +/- 1.4, and 72.1 +/- 4.3. The seeded grafts showed reduced metabolism with the Dynabeads-coated EC. In conclusion, high numbers of beads per cell have a late detrimental effect on cell proliferation and metabolism. Therefore for single-stage seeding lower numbers of Dynabeads will need to be used with resultant reduction in the number of available EC.

Interspecific hybridization of Trifolium alexandrinum with T. constantinopolitanum using embryo rescue

The embryo rescue technique was successfully used to raise hybrids between Trifolium alexandrinum and T. constantinopolitanum. As a result of its narrow genetic base, genetic improvement in Egyptian clover (syn. Berseem; T. alexandrinum), an important fodder crop in tropical and subtropical countries, is hampered, thereby making it imperative to introduce alien genes from related species. In a conventional interspecific hybridization program, hybrids could not be raised due to post-fertilization barriers. Of the several combinations tried, pollination 2 days after emasculation was found to be the best. Globular embryos were observed 5-7 days after pollination (DAP), followed by heart-shaped embryos 10-12 DAP. Embryos excised at the heart-shaped stage responded well to EC3 culture medium. Of 612 crosses, 33 healthy embryos could be excised and cultured on EC3 medium. The plumule emerged 8-12 days following inoculation. The embryo-rescued plants were hardened, inoculated with Rhizobium and transferred to the field. The hybrids showed intermediate morphological features with reduced pollen fertility (55-65%) and a chromosomal complement of 2n = 16. Biochemical characterization using isozymes confirmed hybridity.

Carotid and femoral arterial wall mechanics in scleroderma

OBJECTIVE

Large-vessel arterial disease is increasingly recognized as a major cause of morbidity in autoimmune rheumatic disorders. Recent evidence suggests that scleroderma (systemic sclerosis, SSc) may be linked to altered fibrillin-1 metabolism associated with a defect in chromosome 15q. If this is the case, we may expect to see changes in the arterial wall mechanics of large vessels not clinically involved in the disease process. We undertook a study to determine whether the biomechanical properties and intima-media thickness (IMT) of the elastic carotid artery and the muscular femoral artery are altered in subjects with limited (lcSSc) and diffuse (dcSSc) cutaneous SSc.

METHODS

Measurements of carotid and femoral wall mechanics were made in 33 patients with lcSSc, 19 patients with dcSSc and 21 control subjects, using a duplex scanner coupled to a Wall Track system. Their age, gender, body mass index, heart rate, systolic and diastolic blood pressures, presumed cardiovascular load, and plasma creatinine, fasting cholesterol, triglyceride and glucose concentrations were also measured.

RESULTS

There was a progressive and significant reduction (P < 0.001) in the elastic properties of the carotid artery from the control group (compliance, 16.24 +/- 4.39 %mmHg(-1) x 10(-2)) to the lcSSc group (10.89 +/- 2.43 %mmHg(-1) x 10(-2)) to the dcSSc group (7.65 +/- 2.08 %mmHg(-1) x 10(-2)), even after adjustment for the systemic physiological and biochemical variables studied, which are known to influence the mechanics of arterial walls. There was no apparent difference between the groups in the mean elastic indices of the femoral artery and the IMT of the carotid and femoral arteries.

CONCLUSION

The elastic properties of the carotid artery are significantly altered in SSc, and the two major subsets of SSc may be distinguished by their carotid artery biomechanics. This suggests that connective tissue abnormality occurs at sites not previously assessed.

Extraction of cells for single-stage seeding of vascular-bypass grafts

Experimental data are reported for the seeding of prosthetic vascular grafts with either mesothelial or endothelial cells as part of a research strategy in tissue engineering with the aim of improving graft patency and developing new techniques for single-stage cell extraction and seeding that would give a step reduction in surgery time. New data are reported for two different sources of cells, peritoneal lavage and subcutaneous fat. All experiments were undertaken in patients undergoing abdominal aortic aneurysm repair. Cells extracted from peritoneal lavage were insufficient for a single-stage seeding process. Subcutaneous fat was processed using either a positive cell-extraction method using CD31 Dynabeads or by a negative extraction method using CDw90-coated magnetic beads. Only positive cell extraction gave reliably sufficient numbers of endothelial cells as a source for single-stage seeding of vascular grafts.

Differentiation of primary and secondary Raynaud's disease by carotid arterial stiffness

INTRODUCTION

primary Raynaud's disease may be difficult to differentiate clinically from the secondary form with an underlying connective tissue, haematological, neurovascular or drug-induced disorder. We undertook a study to determine the elastic carotid and muscular femoral arterial biomechanical properties and intima-media thickness (IMT) in subjects with primary and secondary Raynaud's disease, to assess whether these parameters could differentiate the two conditions.

METHODS

twenty patients with primary Raynaud's disease and 53 subjects with secondary Raynaud's associated with scleroderma (systemic sclerosis, SSc) had measurements of their carotid and femoral wall mechanics with a duplex scanner coupled to a Wall Track system. Their age, gender, body mass index, heart rate, systolic and diastolic blood pressures, presumed cardiovascular load, plasma creatinine, fasting cholesterol, triglyceride and glucose concentrations were also measured.

RESULTS

the carotid elastic properties [mean (SD): elastic modulus: 560 (180) vs 1204 (558) mmHg,p <0.001 and stiffness index: 5.69 (1.35) vs 11.92 (6.4), p<0.001 for primary and secondary Raynaud's respectively] were significantly impaired in patients with secondary Raynaud's disease even after adjustment for potentially influencing physiological and biochemical variables. There were no statistical differences in the femoral elastic properties or the carotid and femoral IMTs between the two groups.

CONCLUSION

Duplex determination of the carotid elasticity or stiffness is different in primary Raynaud's phenomenon compared with secondary Raynaud's associated with SSc. This may be a useful non-invasive tool, in addition to autoantibody markers and nail-fold capillaroscopy, to differentiate between the two forms of Raynaud's phenomenon.

Improving the patency of vascular bypass grafts: the role of suture materials and surgical techniques on reducing anastomotic compliance mismatch

BACKGROUND

compliance mismatch is an important factor in the development of myointimal hyperplasia in both coronary and vascular anastomoses. This mismatch may be reduced by the use of newer suture materials and techniques. This review discusses the current techniques and materials used to date in generating anastomoses in both coronary and vascular applications and to correlate these with the degree of inherent compliance achieved.

METHODS

PubMed, ISIS, CAS and PAS database searches were performed. Other articles were cross-referenced.

RESULTS AND CONCLUSION

continuous suture is still the most used technique in both cardiac and vascular surgery for the generation of anastomoses due to the reduced time and improved haemostasis. However, continuous suture results in a greater compliance mismatch than the interrupted technique. Vein cuffs and patches improve compliance and transmission of pulsatile blood flow and offer improvement of graft patency. Alternative to sutures are biological glue, clips and laser generated solders all of which have shown promising results, but further work is required before they become applicable for routine use.

Improving endothelial cell retention for single stage seeding of prosthetic grafts: use of polymer sequences of arginine-glycine-aspartate

OBJECTIVE

single stage seeding within the timeframe of a typical vascular operation has not been successful. One reason for this is poor cell adherence to the graft lumen once exposed to pulsatile blood flow. In this study we have carried out investigations with the use of two different fibronectin-based peptides, fibronectin-like engineered protein polymer (FEPP) which contains multiple copies of arginine-glycine-aspartate (RGD) and fibronectin adhesion promoting peptide (FAPP) to improve cell adherence.

MATERIALS AND METHODS

FAPP and FEPP were coated onto native polyurethane and heparinised polyurethane grafts. The grafts were then seeded for either 1 or 2h with human umbilical vein endothelial cells (HUVEC). After the incubation period the cells were washed off and cell retention was calculated. Cell metabolism was measured using Alamar Blue, and confirmed with scanning electron microscopy (SEM).

RESULTS

heparinised grafts coated with FEPP showed the best cell retention after both 1 and 2h seeding (80+/-4% vs 81+/-3%). This graft had no significant difference in cell retention after both times whilst all the other grafts had better cell retention after a 2h seeding. The Alamar blue and SEM results confirmed cell viability and function for all graft types.

CONCLUSION

heparinised graft coated with FEPP allows significant cell retention after only 1h of seeding and shows promise for single stage seeding.

Installation of solarium--2000 for phototherapy

Sunlight is the cheapest and most easily available source of ultraviolet light for phototherapy. The disadvantage of using sunlight as the source of ultraviolet light includes its variation with time , place and season, lack of privacy, and atmospheric conditions. To ensure correct dose of UV light in spite of variation in irradiation from the sunlight,we used a PMA2100 meter [Figure:2] and 2110 UVA detector ( Solar light Co, Philadelphia). Privacy for the patients was achieved by erecting a solarium and incidental UVB radiation was cut off by using window glass as the roof of the solarium. We recommend the solarium as a less expensive alternative to artificial phototherapy units, especially in places where there is plenty of sunlight.

A simple technique of irrigating the abdomen and pelvis through an appendicectomy wound

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Acute compartment syndromes

BACKGROUND

Acute compartment syndrome is both a limb- and life-threatening emergency that requires prompt treatment. To avoid a delay in diagnosis requires vigilance and, if necessary, intracompartmental pressure measurement. This review encompasses both limb and abdominal compartment syndrome, including aetiology, diagnosis, treatment and outcome.

METHODS

A Pubmed and Cochrane database search was performed. Other articles were cross-referenced.

RESULTS AND CONCLUSION

Diagnosis of limb compartment syndrome is based on clinical vigilance and repeated examination. Many techniques exist for tissue pressure measurement but they are indicated only in doubtful cases, the unconscious or obtunded patient, and children. However, monitoring of pressure has no harmful effect and may allow early fasciotomy, although the intracompartmental pressure threshold for such an undertaking is still unclear. Abdominal compartment syndrome requires measurement of intra-abdominal pressure because clinical diagnosis is difficult. Treatment is by abdominal decompression and secondary closure. Both types of compartment syndrome require prompt treatment to avoid significant sequelae.

Ren and Yuan: a cultural interpretation of Chinese women's responses to battering

The purpose of the study was to examine women's responses to battering within the context of Chinese culture. The stories of 11 Chinese women living in Hong Kong formed the basis of the inquiry. Analysis of the women's accounts revealed Chinese values in their responses to battering: they adopted ren, or endurance, as a coping mechanism and used Yuan, or predestination, as an explanation for their failed relationship. The resilience and resourcefulness of the women are clearly demonstrated in the strategies they employed to cope with the abuse. Their responses to battering were purposeful and varied according to the status of their relationship.

Cellular engineering of vascular bypass grafts: role of chemical coatings for enhancing endothelial cell attachment

Surgical treatment of vascular disease has become common. The use of synthetic materials is limited to grafts larger than 5-6mm, because of the frequency of occlusion observed with small-diameter prosthetics. An alternative would be a hybrid or tissue-engineered graft with the surface coated with a monolayer of the patient's own cells. Currently, to be effective, high-density seeding regimens have to be undertaken. This is because endothelial cells (ECs) are washed off the graft lumen once exposed to physiological blood flow. EC attachment has been shown to be significantly improved by pre-coating with substances known to attach ECs selectively. The review examines the various types of coating and bonding technology used to date to enhance endothelial cell attachment onto the surface of prosthetic vascular bypass grafts.

Trends in the utilization of androgen-deprivation therapy for patients with prostate carcinoma suggest an effect on mortality

BACKGROUND

After a surge in the incidence of prostate carcinoma in the early 1990s, diminishing rates of mortality became apparent in 1993. This decrease in mortality is unlikely to be explained entirely by treatment with curative intent alone following screen-detected cases, because the time frame between detection and mortality remains relatively brief.

METHODS

This study used incidence and initial treatment data from the Detroit area SEER registry between 1973 and 1998 in addition to mortality data covering the Metropolitan Detroit area obtained from the Michigan Department of Community Health. Data for Caucasian and African-American men were analyzed. The use of androgen-deprivation therapy, which evolved during the study period, was evaluated in conjunction with mortality and incidence trend data for consideration of etiologic contributions.

RESULTS

The incidence of prostate carcinoma, as noted previously in national data, increased sharply in 1988, peaking in 1992 in Southeast Michigan, whereas mortality rates began to decrease in approximately 1993, with a sustained decrease to the latest recorded data in 1998. These trends were identical in Caucasians and African Americans. A sharp increase in the use of androgen-deprivation therapy began in 1990. This use of androgen-deprivation therapy is high and sustained for patients with early-stage disease, increases for several years, and then diminishes for patients with regional disease. The use also diminished through the 1990s for patients with late-stage disease, paralleling the decrease in the incidence rate for late-stage disease.

CONCLUSIONS

The pattern of androgen-deprivation therapy usage was consistent with that for hormonal monotherapy and adjuvant and neoadjuvant therapy. These findings suggest that androgen-deprivation therapy may contribute, along with advances in diagnostic techniques and curative therapy with radiation or surgery, toward decreasing prostate carcinoma mortality rates in Southeast Michigan.