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Biomedical subjects

N Pallua

Publications and source records attributed to N Pallua.

At least 37 records · Page 2Linked to original sources
PubMed2005

Cryopreservation of mature human adipocytes: in vitro measurement of viability.

Cryopreservation of fat grafts for autologous fat transplantation renders repeated harvesting procedures unnecessary. Anecdotic reports have been published, yet data about adipocyte survival are sparse. The beneficial effect of added cryoprotective agents (CPA) is known from other tissues but has not been investigated in adipocytes. Fat cells were harvested using the Coleman method (n = 24). Tests were done after 0, 2, 7, 14, and 30 days of cooling to -20 degrees C and -80 degrees C and after addition of various CPA. Analysis included cell stains, measurement of metabolic activity by MTT and XTT tests, and measurement of cell stability by assessment of extracellular glycerol-3-phosphate-dehydrogenase enzyme. After freezing, up to 92.7% of metabolic activity was lost, but the addition of CPA led to preservation of up to 54% of baseline activity. Also, lower storage temperature showed more cell destruction but yielded higher viability of the surviving cells. Our results implicate that the widely used practice of simple storage in a freezer leads to reinjection of nonviable tissue. Cell survival can be improved by addition of CPA.

Adipocytes↗
PubMed2005

Effects of modified collagen matrices on human umbilical vein endothelial cells.

The most commonly used biomaterials fail to ensure sufficient angiogenesis for fast in vivo incorporation. This results in central necrosis and consequent infection. One way of obtaining a high angiogenic response is the application of vascular endothelial growth factor (VEGF). To obtain a sustained release of these cytokines, heparin was incorporated into collagen matrices using 1-ethyl-3(3-dimethyl-aminopropyl) carbodiimide (EDC) and N-hydroxysuccinmide (NHS). The functionality of the heparinized collagen matrices was then enhanced by immobilization of VEGF via its heparin-binding domain. This procedure changed in vitro degradation behavior and water-binding capacity. Accelerated endothelial cell proliferation was also achieved. A range of different heparin and EDC/NHS concentrations in combination with VEGF induced variation in endothelial cell growth and tubulogenic formation. Polymerized collagen scaffolds presented biointeractive systems with integrated angiogenic activity. This may become a useful tool in the clinical therapy of disorders connected with wound healing.

Cell Proliferation↗
PubMed2004

[Varicella associated necrotizing fasciitis in a child].

We present a rare case of necrotizing fasciitis in an 5-year-old infant with preexisting varicella infection. Initially, the patient showed acute pain and swelling of the left thorax with high inflammatory parameters and varicella-specific skin affections. MRT presented diffuse soft tissue swelling of the left chest consistent with necrotizing fasciitis. After aggressive surgical debridement of necrotic tissue and extirpation of axillary lymph nodes, the clinical course improved under appropriate parenteral antimicrobial therapy using penicillin and clindamycin. In conclusion, necrotizing fasciitis should be suspected in any child with a history of varicella infection and increasing complaints of pain and swelling in an extremity or other body area associated with increasing fever, erythema, lethargy, and irritability. Shock, multiorgan failure, and death will ensue if the diagnosis is not promptly recognized.

Chickenpox↗
PubMed2004

The arterial vascularisation of the abdominal wall with special regard to the umbilicus.

AIM: In order to prevent wound healing problems around the transposed umbilicus following abdominoplasty, we investigated the arterial vascularisation of the abdominal wall with special regard to the umbilicus. The aim was to optimise the planning of the umbilical stalk and flap design. METHOD: The inferior and superior epigastric arteries of 12 cadavers (mean age 83 years) were injected with barium-sulphate, lead-mennige and gelatine. The abdominal walls were resected en bloc and X-ray photographs were taken by conventional and mammographic technique. RESULTS: The radiographic examination showed that the main trunks of the epigastric vessels follow an "hour-glass" or "rhomboid" pattern around the centromedial umbilicus. Each main trunk splits into two obligate branches one medial and one lateral. The anastomosis between the inferior and superior epigastric artery is located above the umbilicus. The umbilicus is nourished by separate axial vessels originating from the inferior epigastric artery. It was also shown that the inferior intercostal arteries anastomose with the branches of the inferior and superior epigastric artery. CONCLUSION: Dividing the abdominal wall into four quadrants around the central umbilicus, the lateral areas of the lower quadrants show the weakest vascularisation by the inferior epigastric artery. This fact may cause healing problems after surgery in this area. The axial vascularisation of the umbilicus makes any torsion or traction a potential hazard to the umbilical flap during abdominoplasty especially by re-siting the umbilicus. The anatomical study showed clearly the benefit of preparing a broad base fat layer with a generous diameter of incision line around the umbilicus.

Abdominal Wall↗
PubMed2004

Is high PEEP low volume ventilation in burn patients beneficial? A retrospective study of 61 patients.

In burn care lung damage by inhalation injury is a major cause of mortality in burn patients. In the field of intensive care medicine ventilation strategies to reduce lung injury caused by ventilation are under investigation. The promising results of the application of pressure controlled high PEEP low volume (HPLV) ventilation prompted us to use this ventilation strategy in our burn ICU. To establish whether this ventilation regime is beneficial the charts of 61 consecutive patients needing artificial respiration were reviewed. A scoring system for PEEP level and tidal volume was developed and treatment groups with high PEEP and low volume and low PEEP high volume regimes were compared. No statistically significant differences could be found when comparing treatment versus mortality, the number of pulmonary complications or incidence of pneumothoraces. However, the trend showed a benefit in mortality for patients with an ABSI scoring up to 9, but at the same time pulmonary complications increase. The Horovitz oxygenation index showed no advantage for the HPLV Group. In a separate analysis we found a significant correlation between absolute PEEP and mortality. The correlation between PEEP level and mortality is a dynamic factor predicting outcome, This not been described yet and can be an addition to the static ABSI score. Differences between ventilation strategies were not as evident as expected in this retrospective study, so prospective randomized studies are needed.

Adult↗
PubMed2004

Update on the use of collagen/glycosaminoglycate skin substitute-six years of experiences with artificial skin in 15 German burn centers.

The clinical use of an artificial skin substitute (Integra) has been celebrated enthusiastically as an improvement in burn therapy over a period of more than 10 years. Many case-reports have shown the positive effects of the treatment with Integra as a skin substitute. In this study we examine the alterations of Integra-usage in Germany. Fifteen German burn centres have been interviewed respectively over a time period of 6 years with interviews in the years 1999, 2001, and 2003. The goal of this study is to focus on the problems associated with the use of artificial skin and to create a manual for Integra-therapy including indication, pre-, intra-, and postoperative treatment. Since the first Integra Users seminar in Germany in 1999 repeated interviews have been conducted with fifteen German burn centres. The collected results of the last 6 years were evaluated. These results show a change in the indication for the therapy with artificial skin towards extensive full thickness burned patients and as extended indication especially for posttraumatic reconstruction. This article gives our guidelines for the usage and handling of Integra and shows that Integra is an important reconstructive dermal substitute for the severely burned or posttraumatic patient if handled by a skilled surgeon in a correct way.

Anti-Infective Agents, Local↗
PubMed2003

[Radical scapulectomy with trapezius flap in soft tissue sarcoma of the shoulder girdle].

In soft-tissue sarcoma, wide tumour excision (R0) has become the most important factor in local tumour control. Nowadays, radical scapulectomy with limb salvage is the treatment of choice for soft-tissue sarcomas of the shoulder girdle. We present the case of a 78-year-old man with extended low-grade fibrosarcoma of the left shoulder girdle. Despite his age, radical scapulectomy with intraoperative radiation and functional reconstruction of the shoulder girdle with a myocutaneous trapezius flap was performed. Good functional and aesthetic results could be obtained.

Aged↗
PubMed2003

Psychosocial adjustments 5 years after burn injury.

The present study investigates factors influencing the quality of life and social reintegration of burn victims. A study concept was developed to assess the functional and aesthetic long-term outcomes of burn victims. Objective data from a clinical examination was correlated with subjective data from completed questionnaires. The success of social rehabilitation was documented and an indicative profile of life quality evaluated. This profile could prompt early intervention if found necessary. Ninety-two patients were examined 5.4+/-1.1 years after trauma in relation to three factors: physical functions, localization of the burn injuries and extent of the body surface area burned. Physical functioning allows the best predictions for successful rehabilitation, because all areas of life quality are affected by it. Localization of burns in the face and hands creates disadvantages in social reintegration. Of less value in prediction is the extent of the body surface area burned, which is only closely linked to occupational rehabilitation and directly correlates to physical functional limitations. Our correlation showed, that even slight functional limitations were linked to severe depressions, similar to the values found with patients with serious functional impairment. Interdisciplinary cooperation between plastic surgeons and psychosomatic specialists will optimize early intervention with patients exposed to social maladaptation.

Adaptation, Psychological↗
PubMed2003

Ancient traditional Chinese medicine in burn treatment: a historical review.

Burn treatment in traditional Chinese medicine (TCM) has a long and remarkable history. This article provides a review of it's philosophy and knowledge, basic principles and treatment strategies as well as their modifications during 1300 years of medical development. The specific features presented are still influencing modern traditional Chinese medicine practitioners as well as modern Chinese burn treatment with considerable benefit for the treatment of burn victims.

Burns↗
PubMed2003

[A rare case of cannabis arteritis].

A 24-year old woman, heavy cannabis smoker with progressive Raynauld's phenomenon and digital necrosis is presented. Systemic sclerosis and other connective tissue disorders as well as arteriosclerosis and arterial emboli were excluded with appropriate laboratory examinations. Arteriography revealed multiple forearm, palmar and digital occlusions with corkscrew-shaped vessels. Based on these characteristic arteriography and clinical findings, the diagnosis of cannabis-arteritis was finally retained. With careful necrectomy, conservative wound dressings and secondary prostacyclin therapy a complete healing of digital necrosis was observed. There was no recurrence during the 6 month-follow-up. This observation demonstrates that cannabis may represent a possible cofactor in the pathogenesis of arteritis in young smokers. Early recognition is important to avoid irreversible complications such as loss of digits.

Adult↗
PubMed2003

[Reconstruction of defects at the neuromuscular junction].

Loss of muscle tissue at the area of the neuromuscular junction after tumor resection or after trauma precludes the reconstruction with conventional nerve grafts, because the distal nerve stump is absent. For these cases, we recommend direct insertion of the nerve grafts into the muscle. We describe a standardized technique, which has been performed in 19 patients and led to a mean motor recovery of grade M4 after Highet. The key procedure of this technique is the interfascicular dissection of the nerve grafts, which allows a wide distribution of the grafts into the muscle tissue.

Adult↗
PubMed2003

Preadipocyte-loaded collagen scaffolds with enlarged pore size for improved soft tissue engineering.

Extended soft tissue defects after extensive deep burns or tumor resections are still an unresolved problem in plastic and reconstructive surgery. There is a clinical need for an adequate solution to this problem but currently, no adequate implant material is available for the correction of these defects. Since the autologous transplantation of mature adipose tissue gives poor results, this study explores the advantages of using human preadipocytes in collagen sponges for tissue reconstruction purposes. Human preadipocytes of young adults were isolated, cultured, seeded onto collagen sponges with uniform pore size, and implanted into immunodeficient mice. After 24 hours of incubation in vitro and after explantation at 3, 8, and 12 weeks, sponges were examined for macroscopic appearance, weight, thickness, histology, immuno-histochemistry, and ultrastructure. We find good penetration of cells into the scaffold, layers of adipose tissue, and new vessels on all grafts while controls appear unchanged. These results are promising for improving the reconstruction of soft tissue defects.

Adipocytes↗
PubMed2002

[The burned hand. A computer-assisted study of late function of 67 burned and operated hands].

A good functional outcome of the hand is important in the rehabilitation of severely burned patients. The aim of the study was to evaluate the late functional outcome of deeply burned hands using a computer aided system and to correlate the function with the distribution of the hand burns. Over a 12-year-period 378 patients whose acutely burned hands had been operated on at the burn center of the university hospital Aachen were invited to a follow-up examination. 67 burned and operated hands were evaluated 57 (3-364) months after the burn by the computerized evaluation system EVAL. Active flexion and extension, grip strength, pinch (key, 3-tip and 2-tip), moving 2-point sensitivity and the pattern of skin grafts and scars were assessed. The use of the hand in daily activities was evaluated by a questionnaire. The hands were classified in 4 groups according to the burn pattern: I: patchy burns (total < 12 cm2), II: confluent dorsal burns, III: confluent palmar burns, IV: mutilating burns. Good results were found in group I (n = 25), comparable to normal hand function. In group II (n = 25) there was a significant loss of total active flexion with preserved strength. Increased extension lag and impaired grip strength characterized group III (n = 8). Late functional results in group IV (n = 9) depended on the reconstructive procedure. Between the 4 groups there were significant differences in function. The results were well correlated to the burn pattern and its extent according the classification.

Activities of Daily Living↗
PubMed2002

The use of bifunctional polyethyleneglycol derivatives for coupling of proteins to and cross-linking of collagen matrices.

The realization of three-dimensional (3D) degradable matrices which slowly release bio-active components represents a major challenge in the field of tissue engineering. In this paper we report on the usage of commercially available bifunctional agents for both the covalent coupling of proteins to and the cross-linking of collagen matrices. Proteins - horse radish peroxidase (HRP) was used as a model protein - were cross-linked with either a homobifunctional (disuccinimidyldisuccinatepolyethylene-glycol) or a heterobifunctional (N-hydroxysuccinimidylvinylsulfonepolyethyleneglycol) agent. In the case of the heterobifunctional cross-linking agent the collagen matrices were previously modified with succinimidylacetylthioacetate in order to introduce sulfhydryl groups. As compared with control experiments a 10-fold and 50-fold increase of immobilized proteins were achieved with the homobifunctional and heterobifunctional cross-linker resp. The HRP-PEG conjugates demonstrated a better long-term stability as compared to the non-treated HRP. The effects of the cross-linking agents and the thiolation reagent succinimidylacetylthio acetate on the in vitro degradation of the collagen matrices by collagenase were also investigated. In particular the reaction with succinimidylacetylthio acetate appears to offer interesting opportunities both for coupling active proteins and modulating the degradation times of collagen matrices.

Journal Article↗
PubMed2002

Extensor-tendon hypoplasia and multiple pterygia: Escobar syndrome in a 7-year-old boy.

Escobar syndrome is a rare condition with autosomal-recessive inheritance, characterised by multiple pterygia, kyphoscoliosis, multiple joint contractures and craniofacial dysmorphisms. A number of other abnormalities are also attributed to the syndrome. Here, we present a case of isolated extrinsic extensor-tendon hypoplasia of the right index finger in a 7-year-old patient with Escobar syndrome. To our knowledge, this has not been previously described in connection with this syndrome.

Abnormalities, Multiple↗
PubMed2002

The cervical rib. A predisposing factor for obstetric brachial plexus lesions.

Controversy surrounds the aetiology of obstetric brachial plexus lesions. Most authors consider that it is caused by traction or compression of the brachial plexus during delivery. Some patients, however, present without a history of major traction during delivery, and some delivered by Caesarean section also suffer the injury. In our series of 42 infants, 28 had an Erb's palsy, and the remaining 14 presented with a more extensive lesion, involving the lower roots. In five of these, a complete ossified cervical rib was found. We believe that anatomical variations, such as cervical ribs or fibrous bands, can cause narrowing of the supracostoclavicular space, and render the adjacent nerves more susceptible to external trauma.

Brachial Plexus Neuropathies↗
PubMed2001

[Therapy of soft tissue trauma in the acute phase of severe hand injuries].

INTRODUCTION: Complex hand injuries are characterized by a combination of soft tissue injury and additional trauma to functional structures such as nerves, bones, tendons, vessels and joints. A good functional result requires the reconstruction of the injured structures and early mobilisation. Good vascularized soft tissue and stable osteosyntheses are the major prerequisites to avoid infections and to allow early mobilisation. The optimal timing for soft tissue reconstruction remains controversial with respect to the incidence of infections. METHODS: We have evaluated retrospectively our series of complex hand injuries addressing the question whether a delay of soft tissue coverage for up to 72 hours causes significant increase of infection rates. RESULTS: 48 patients were treated with complex injuries of the hand within a three year period between December 1998 and December 2000. The lowest incidence of infections occurred in the group, where soft tissue coverage was completed as an emergency procedure. DISCUSSION: Ideally primary reconstruction of complex hand injuries should be strived for to minimize scar formation as a result of secondary operations and further immobilisation periods. This includes, if necessary, free tissue transfer. Exceptions are situations where the vitality of soft remains uncertain. In these cases, definitive surgery is delayed for a maximum period of 72 hours.

Acute Disease↗