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Biomedical subjects

Yehuda Ullmann

Publications and source records attributed to Yehuda Ullmann.

32 records · Page 2Linked to original sources
PubMed2004

Aging of human epidermis: reversal of aging changes correlates with reversal of keratinocyte fas expression and apoptosis.

The goal of this study was to determine the role of Fas-mediated apoptosis in human epidermal aging. Epidermal Fas expression and apoptosis are increased in aged human skin. Aging changes of human epidermis, including decreased epidermal thickness and proliferation, are reversed following grafting of human skin to SCID (severe combined immunodeficiency) mice. Skin from aged participants (n = 14; mean 70.7 years), and young participants (n = 14; mean 23.4 years) was grafted to beige SCID mice, and epidermal thickness, proliferation (Ki-67 expression), apoptosis (TUNEL [Tdt-mediated dUTP nick end labeling] reaction below granular layer), and expression of Fas and FasL were determined by histology and immunochemical staining. Aged skin was associated with thinning of the epidermis, decreased epidermal proliferation, a significant increase in apoptosis below the granular layer, and epidermal Fas expression. Engraftment significantly reversed these aging changes, including apoptosis, and Fas expression. Correlation of reversal of aging changes, with decreased epidermal Fas expression and apoptosis, supports a role for Fas-mediated apoptosis in aging of human epidermis.

Adolescent↗
PubMed2004

Using intense pulsed light for cosmetic purposes: our experience.

The authors' experience using intense pulsed light for skin rejuvenation is summarized and analyzed with regard to its efficacy, safety, and complications. Rejuvenation using intense pulsed light was performed on 59 patients over a 6-month period (January of 2002 to July of 2002); these patients served as the study group. The areas treated were the face, neck, chest, hands, and legs. The parameters used during the procedure, patient satisfaction, and complications are described. Ninety-five percent of the patients included in the study had one or two sessions. Good to very good results were reported by 93.1 percent. Most patients had minor side effects and only three patients (5 percent) experienced complications (hyperpigmentation or scars). Intense pulsed light is an effective and safe method for skin rejuvenation. Its efficacy is mainly manifested by eliminating senile pigmentation and telangiectasias and a achieving a younger and fresher appearance of the skin. Although in the literature intense pulsed light skin rejuvenation is mainly reported for the face, the authors have obtained good results by using it for other areas of the body. The majority of the patients were satisfied. The authors conclude that intense pulsed light skin rejuvenation is a safe and effective method for facial and nonfacial rejuvenation.

Adult↗
PubMed2004

Superextended facelift: our experience with 3,580 patients.

Our experience using the "Superextended" facelifting technique in 3580 female patients is presented herein. The technique is based on extended subcutaneous facial and neck skin undermining, extensive superficial musculoaponeurotic system (SMAS) dissection with low lateral freeing of the edges of the platysma muscle. The trimmed SMAS is fixed to the adjacent tissues, enabling the upward and lateral pulling effect of the facial structures. The neck contour is rebuilt by lateral pulling and fixing of the dissected lateral platysmal edges, along the entire neck, and meticulous supraplatysmal fat sculpturing. The skin is redraped over the newly built SMAS and platysmal skeleton, trimmed, and sutured without any tension. The concept of beauty in the eyes of the surgeon is expressed by adding other ancillary procedures during or shortly after the main procedure. Subcutaneous forehead lift using the hairline incision was performed in 70% of the female patients, concomitantly with the face-lifting procedure. Upper and lower blepharoplasties, chin implant, perioral dermabrasion, rhinoplasty, and fat grafting have been performed according to the surgeon's judgment and the patient's request. The objectives of an ideal facial surgery, which are youthful, natural, dynamic, attractive, feminine, and long-lasting results, can be achieved using this technique. Lack of major complications and an overall minor complications rate of only 4.4% makes this technique safe, reproducible, and reliable. This is one of the largest presented series of this procedure, performed by 1 surgeon. The presented cases demonstrate the results obtained using this technique.

Esthetics↗
PubMed2004

Acute shortening: modular treatment modality for severe combined bone and soft tissue loss of the extremities.

BACKGROUND: Acute shortening, using the Ilizarov technique followed by progressive lengthening, is one of the methods used to deal with complex fractures combined with severe soft tissue injuries. METHODS: We have summarized 12 patients who underwent acute shortening and stabilization using the Ilizarov frame. Nine of them underwent progressive lengthening to restore the length. For three patients, angulation of the bone segments was performed to save them from excessive bone debridement. RESULTS: Total wound closure and bone regeneration were achieved in all our patients. Five patients had pin-tract infection without involvement of the bone, and no major complications were noted. CONCLUSION: Using this technique, we found some advantages. First, there is less need for free and local flaps. Second, there is a decrease in the operating time and donor-site morbidity (important for patients with multiple organ trauma). Third, it provides a good option for restoring defects in severe cases with combined bone and soft tissue defects in the same session. Fourth, its implementation for short bone defects (< 3 cm) gives acceptable aesthetic and functional results. Fifth, angulation of the segments and subsequent graduated correction of misalignment reduces the length of shortening needed in patients with severe soft tissue loss by sparing the bone from unnecessary debridement. Sixth, it permits definitive treatment using an external fixator device, enabling the possibility of early functional loading. On the basis of our experience, we suggest adopting this method for functional limb salvage after extensive complex high-energy injuries.

Adult↗
PubMed2004

Green fluorescent protein (GFP) as a vital marker for pathogenic development of the dermatophyte Trichophyton mentagrophytes.

Skin infections by dermatophytes of the genus Trichophyton are widespread, but methods to investigate the molecular basis of pathogenicity are only starting to be developed. The initial stages of growth on the host can only be studied by electron microscopy, which requires fixing the tissue. This paper shows that restriction-enzyme-mediated integration (REMI) provides stable expression of the green fluorescent protein (GFP) in a clinical isolate of Trichophyton mentagrophytes. Under control of a constitutively active fungal promoter, GFP renders the hyphae fluorescent both in culture and in a recently developed model using human skin explants. Stages of infection and penetration into the skin layers were visualized by confocal microscopy. The stages of infection can thus be followed using GFP as a vital marker, and this method will also provide, for the first time, a means to follow gene expression during infection of skin by dermatophyte fungi.

Base Sequence↗
PubMed2003

Transfer of alopecia areata in the human scalp graft/Prkdc(scid) (SCID) mouse system is characterized by a TH1 response.

Alopecia areata is an autoimmune condition directed at hair follicles, which results in loss of hair. We have previously demonstrated that it is possible to transfer hair loss, along with the immunohistologic findings of alopecia areata, to human scalp grafts on Prkdc(scid) (SCID) mice by injection of autologous activated lesional T-cells. This study examines the cytokine profile of T-cells and follicular epithelium following transfer of hair loss. Two consistent findings significantly (P < 0.01) associated with hair loss were production of interferon-gamma-inducible protein-10 kDa (IP-10) by follicular epithelium (13/13), and production of INF-gamma by infiltrating T-cells (10/12). Noninjected control grafts regrew hair, and were generally negative for IP-10 (positive 2/9), and INF-gamma (positive 2/9), but expressed of IL-10 on the follicular epithelium (7/9). These data support an INF-gamma TH1 pathogenesis for hair loss in alopecia areata.

Alopecia Areata↗
PubMed2003

Fate of exposed breast implants in augmentation mammoplasty.

Exposure of silicone breast implants usually leads to infection and extrusion. According to the literature, implant extrusion rates are not higher than 2% 1 and removal of the implant is recommended. 2 During the past 3 years, the authors dealt with eight implant exposures (six women: two cases of bilateral exposure and four cases of unilateral exposure). All the pockets were infected. Patients were offered two alternatives: immediate removal of the implant and reimplantation after a few months or conservative treatment with an effort to close the exposed area after the discharge stopped. All the patients in this study chose the latter alternative. Four out of eight implants were saved. The authors had to remove the other four. The average follow-up of these women was 2 years and there were no signs of capsular contracture or any other problems. According to this series, 50% of eight exposed breast implants could be saved with conservative treatment.

Adult↗
PubMed2002

Psoriasis is mediated by a cutaneous defect triggered by activated immunocytes: induction of psoriasis by cells with natural killer receptors.

This study was performed to ask whether psoriasis is a unique pathologic response of epidermis of psoriatic patients, or cells with natural killer receptors can induce psoriatic changes in skin from nonpsoriatic donors. Human nonlesional skin from five psoriatics, as well as from seven nonpsoriatics was grafted on to beige-SCID mice. Lymphocyte lines with natural killer activity, and mixed natural killer, natural killer T cell phenotype, were generated by culture of peripheral blood mononuclear cells from both psoriatic, and normal donors, in 100 U interleukin-2 per ml for 14 d. Natural killer cells were injected into the human skin grafts, and the grafts were harvested after 4 wk. Injection of natural killer cells from psoriatic donors into autologous nonlesional psoriatic skin resulted in classic psoriasis histology with a significant increase in epidermal thickness, and proliferation, as well as expression of epidermal human leukocyte antigen DR, intercellular adhesion molecule-1, CD1d, and K-16. Superantigen stimulation was not necessary. In contrast, injection of natural killer cells from normal donors into autologous normal skin did not induce the histology of psoriasis, but that of psoriasiform dermatitis. This is a nonspecific reaction pattern. These grafts also exhibited a significant increase in epidermal thickness, and proliferation. Differences from psoriasis included mild epidermal edema (spongiosis), hypergranulosis, irregular elongation of rete ridges, and lack of thinning of the suprapapillary plate. Injection of allogeneic natural killer cells into grafts also resulted in psoriasiform dermatitis, regardless of the source of natural killer cells, or skin. Psoriasis induction by cells with natural killer receptors appears to be dependent upon the source of skin. This suggests that psoriasis results from a cutaneous defect that is triggered by an autoimmune activation.

Animals↗
PubMed2002

Four parallel flaps for correction of a wide forehead defect.

A simple method for closure of a defect in the forehead area by four parallel flaps along the forehead wrinkle lines is illustrated. The main advantage of this method lies in its simple design, which enables the surgeon to close large defects with no elevation of the eyebrow, while preserving the hairline, and most of the suture lines are parallel to the forehead wrinkle lines.

Aged↗
PubMed2002

Early nonsurgical correction of congenital auricular deformities.

Congenital auricular deformation is not an uncommon phenomenon, and it may cause substantial annoyance to the growing child. Many parents of affected children will seek surgical correction of the deformed auricles. The variety of techniques that have been described for the correction of this anomaly suggests that none has been considered satisfying. The consequent possible surgical complications should also be considered, when the surgical procedure can be replaced by an effective conservative treatment. The authors describe their experience using early splinting for congenital auricular deformities. Fifty-two newborn infants with lop, prominent, Stahl's, and constricted ears referred to us by the neonatal department staff were enrolled in this study. Putty Soft, a vinyl polysiloxane impression material, has been used for early molding of the auricles. Surgical tapes were used for the fixation of the mold and to fix the auricle to the scalp. The results were evaluated by one of the parents and by a layperson (medical student) 6 months after completion of the procedure. The above-described early splinting procedure was applied onto 92 auricles of 52 newborn infants aged 1 to 10 days, mostly around day 3. The mean treatment time was 6.8 weeks. All treated auricles were improved, 87 percent were rated as excellent improvement, and there were no complications related to the treatment. The authors conclude that early splinting of deformed auricles should be offered to parents of affected children, and the awareness of this procedure by neonatologists, pediatricians, and nursery staff should be increased.

Age Factors↗
PubMedDate not supplied

Long-term fat preservation.

The injection of autologous free fat obtained by suction-assisted lipectomy for the correction of soft tissue defects is a common procedure in plastic surgery. However, unpredictable partial absorption of the injected fat often necessitates repeated harvesting and injection. Fat preservation for future re-injection is indicated to avoid repeated fat harvesting procedures. A previous study has shown that fat obtained by suction can be preserved by freezing for at least 2 weeks. The purpose of the present study was to investigate the effect of freezing autologous free fat for 7 months on the take of the fat graft. Human fat obtained by suction-assisted lipectomy was centrifuged and stored in a domestic refrigerator at -18 degrees C for 7 months. After thawing, the fat was injected into the scalp of 10 nude mice, which served as the study group. In the control group (n = 10), fresh fat was injected. Fifteen weeks later, the fat grafts were dissected out. Volumes, weights, and histological parameters were compared between the groups. The injected fat survived in both the study and the control groups but the histological parameters were significantly inferior in the frozen fat. The weight of the frozen fat was also significantly less compared with the fresh fat. The volume of the frozen fat was inferior but not significantly. Based on this in vivo experiment, it is suggested to refrain from using fat that has been frozen for 7 months or longer. The longest period and the optimal conditions for fat preservation should be further investigated.

Adipose Tissue↗
PubMedDate not supplied

The effect of lidocaine and adrenaline on the viability of injected adipose tissue--an experimental study in nude mice.

Adipose tissue injection as a free graft for the correction of soft tissue defects is a widespread procedure in plastic surgery. The main problem in achieving long-term soft tissue augmentation is partial absorption of the injected fat, and hence the need for over-correction and re-injections. Lidocaine, used for local anesthesia, has been suspected as an inhibitor of growth of adipocytes in culture and slowing down glucose transport and lipolysis in adipocytes. In addition, reduced blood supply by local application of epinephrine was accused of having a negative effect on the graft. The purpose of this study was to examine the effect of local anesthesia, administered to the fat donor site, on the take of the injected fat. Human adipose tissue, obtained by suction-assisted lipectomy, was injected subcutaneously into the scalp of nude mice. Local anesthesia of the fat donor site consisted of a solution with 600 mg of lidocaine (0.06%) and epinephrine 1:1000000. In a control group, normal saline with no local anesthesia or epinephrine was administered to the donor site. One cc of fat was injected after centrifugation into each animal scalp. There were 10 animals in each group. The animals were sacrificed 15 weeks after the procedure. Graft weight and volume were measured, and histologic evaluation was performed. No significant differences were demonstrated between the groups in regard with the grafts' weight and volume and the histologic parameters investigated. In conclusion, local anesthesia solution, consisting of lidocaine and epinephrine, does not alter the take of fat grafts, and has no influence on the adipocytes viability.

Adipose Tissue↗