Novel application method of artificial dermis: one-step grafting procedure of artificial dermis and skin, rat experimental study

BACKGROUND: Currently, to treat skin defects with artificial dermis (AD), two surgical procedures where the artificial dermis grafting and another secondary skin grafting are required. The purpose of this study was to achieve simultaneous grafting of the artificial dermis and the split-skin. To enhance the wound angiogenesis, cultured endothelial cells, fibroblasts and PDWHF (platelet derived wound healing factor) were employed. METHODS: The experiment consists of following two parts: (1) Investigation to obtain faster angiogenesis into the bilayer artificial dermis: full-thickness wounds created on the back of the rats were treated with the artificial dermis (Terudermis, with silicone sheet, TERUMO Co., Japan). Prior to the artificial dermis grafting, following four groups were established; control group (AD alone, n=6), PDWHF group (AD treated with PDWHF, n=6), cultured cells group (AD treated with cultured endothelial cells and fibroblasts, n=6), combination group (AD treated with PDWHF and cultured cells, n=6). (2) Trial of one-stage grafting of the AD and the skin: simultaneous grafting of the artificial dermis and skin was performed using the same rat model. Before making skin defects, split thickness skin were harvested. Then the skin grafting was carried out immediately after the AD grafting. To allow grafting of the skin onto the artificial dermis, the AD without silicone sheet (Terudermis without silicone sheet, TERUMO Co., Japan) were used. Two groups, control group (AD alone, n=3) and treatment group (AD with PDWF and cultures, n=3) were established. RESULTS: (1) When the artificial dermis were treated with PDWHF, cultured endothelial cells and fibroblasts, vascular invasion into the artificial dermis was observed 5 days after the surgery. (2) In the treatment group, the skin grafted immediately after the artificial dermis grafting was completely taken. CONCLUSIONS: The present study revealed that treatment with PDWHF, combined with cultured endothelial cells and fibroblasts, accelerated wound angiogenesis. By this method, one-step grafting procedure of the artificial dermis and the skin is possible.     

Hepatitis C Virus Infection is Highly Correlated with Hepatocellular Apoptosis and Transforming Growth Factor‐β1 MRNA Expression in Patients with Chronic Hepatitis C

Introduction:  The cellular phases (granulation, reepithelialization, and dermal remodelling) of the healing process involve many cell types. Fibroblasts and myofibroblasts are the key cells in granulation tissue formation and wound contraction.
Objective:  To compare the effects on cultured human fibroblasts of a new nonadhesive lipidocolloid wound dressing, Urgotul^®, with five other wound dressings including impregnated gauzes and some other modern wound dressings.
Method:  Cultures in monolayer were used to study the morphology and growth of fibroblasts. The Bell model of cultured dermis equivalents was used to investigate myofibroblast differentiation. These cultures were labelled α‐SM actin and F‐actin.
Results:  Two of the tested dressings induced cytotoxic effects on the fibroblasts. They were found to inhibit cell growth (greater than 60%) and to disturb cell shape and cytoskeletal differentiation. Urgotul^® and the remaining three dressings showed no effect on proliferation. However some of them modified fibroblast morphology and affected F‐actin distribution.
Conclusion:  Depending on their nature and components, wound dressings may respect or affect in vitro fibroblast behaviour (proliferation, morphology, and α‐SM actin and F‐actin distribution). The observed in vitro findings require further investigations.     

One-step grafting procedure using artificial dermis and split-thickness skin in burn patients

The study aimed to achieve a one-step grafting procedure using artificial dermis and split-thickness skin. We performed simultaneous grafting of artificial dermis and skin in two severely burned patients. Artificial dermis was treated with fresh autogenous platelet-derived wound-healing factors (PDWHF), cryopreserved allogeneic cultured endothelial cells, and fibroblasts. Dermal microvascular endothelial cells and fibroblasts were obtained from a single human donor’s skin. The cultured cells were cryopreserved until use in grafting. The PDWHF was prepared from autogenous blood from each patient prior to the surgery. In two patients, the artificial dermis treated with this method was grafted to a full-thickness burn wound. Immediately after artificial dermis grafting, meshed split-thickness skin was grafted. In each case, the skin graft took well, and the skin texture was acceptable. Histological examination revealed that bovine collagen tissue remained in the dermis after surgery, indicating the success of the simultaneous grafting of the artificial dermis and the skin. The present study indicates that one-step grafting of artificial dermis and split-skin is possible when the artificial dermis is treated with PDWHF and cultured endothelial cells and fibroblasts. Level of Evidence: Level V, therapeutic study.     

血管内皮细胞和成纤维细胞混合移植对人工真皮血管化的影响

目的观察同种血管内皮细胞和成纤维细胞移植对人工真皮血管化的促进作用。方法在27只Wistar大鼠背部造成2．5 cm×2．5 cm全层皮肤缺损创面(2处／只),将其分为血管内皮细胞组:将血管内皮细胞混入0．5 ml纤维蛋白胶中,按1．0×105／cm2的密度均匀喷洒于移植床;混合组:将血管内皮细胞和成纤维细胞混入等量纤维蛋白胶后,同前密度喷洒于移植床;对照组:按同样方法喷洒等量纤维蛋白胶。随后各组移植人工真皮,每组9只大鼠18处创面。于移植后5、10 d切取移植的真皮及周围组织行HE、血管内皮生长因子(VEGF)、Masson和墨汁灌注染色,观察新生血管生长情况。于移植后5 d行伊文思蓝灌注,以分光光度计定量检测法测定微血管形成情况。结果移植后5 d,HE、VEGF、Masson和墨汁灌注染色均可见各组移植床有新生血管长入。HE染色见血管内皮细胞组、混合组新生血管数量分别为(14．2±3．6)、(12．1±2．5)条,较对照组[(3．9±1．6)条]明显增多(P<0．05)。移植后10 d,人工真皮内及移植床均有微血管形成,且胶原组织的合成增加。移植后5 d,经伊文思蓝灌注,收集并检测血管内皮细胞组、混合组真皮组织溶出的上清液,吸光度值分别为0．167±0．058、0．155±0．046,均高于对照组的0．066±0．024(P<0．05)。结论同种血管内皮细胞和成纤维细胞移植可促进创面愈合过程中的血管新生,加速人工真皮移植后血管化过程,促进类真皮组织的成熟。     

Chitosan Sponge with Photocrosslinkable Chitosan Hydrogel Stimulates Large and Impaired Wound Healing in Rats

Aim:  The silicone polymer is known to be useful and safety as a material of medical implants. But fundamentally its biocompatibility and biostability are questionable. Thus we try to make a hybrid‐type silicone implant coating by cell layers. At first, we aimed to confirm cell adhesion and growth on silicone surface.
Material:  Group 1 is silicone implants for the augmentation rhinoplasty with no treatment. Group 2 is same type silicone implants with surface modifications by O₂ plasma treatment (3 min). Group 3 is the group 2 implants with serum and plasma coating (20 min).
Method:  We co‐cultured materials of each group with human fibroblast (2.4*10⁴ cells/ml), for 17 hours, with 5%CO₂, in the temperatures of 37 °C.
Results:  Group 1; none of fibroblasts could take the surface of materials.
Group 2; several fibroblasts were found on the surface of those.
Group 3; much more fibroblasts were found than group 2
This result means that the surface modification by O₂ plasma treatment itself enables the cell adhesion and growth on silicone surface.     

Effects of an Inhibitor of Nitric Oxide Synthesis on Skin Wound Repair

Introduction:  The aim of this study was to compare the effects of Urgotul^® and other greasy dressings and interfaces on normal human dermal fibroblasts (NHDF) monolayers in vitro . The selected end points were the cell proliferation, the morphology of the extracellular matrix (ECM) upon dressing removal, and the structure of the underlying fibroblasts.
Materials and methods:  Equivalent pieces of each dressing were applied on NHDF monolayers for different times. Cell proliferation was measured via [3H] thymidine incorporation. Identical cultures were used to assess the dressing impact on the morphology of cells in culture after MTT staining and micro‐photographing. ECM morphology was shown by immunoflorescence, using an anticollagen I antibody. Effects on cell ultrastructure were documented by confocal laser microscopy after tubulin/actin double labelling.
Results:  Among the five tested greasy dressings and interfaces, only Urgotul^® showed a stimulating effect on the proliferation of NHDF. Two dressings did not modify proliferation and two other had cytostatic effects.
In addition, the lesions of the ECM upon dressing removal were clearly the lowest with Urgotul^®(low adherence to cellular surface and/or to extracellular matrix). The ultrastructure of the NHDF in direct contact with Urgotul^® was not significantly modified.
Conclusion:  Fibroblasts are the key cells of wound healing. The use of nonaggressive greasy gauzes and/or interfaces promoting cell proliferation should be of interest. Clinical evaluations are required to confirm these in vitro results.     

Pulmonary inflammatory mediators after sevoflurane and thiopentone anaesthesia in pigs

Background:  Volatile anaesthetics have been shown to affect the release of pulmonary inflammatory mediators and exacerbate pulmonary injury after experimental aspiration. Thus, in theory, volatile anaesthetics may worsen inflammatory pulmonary injury and disease. We have previously described that no significant changes in alveolar ultrastructure are seen after sevoflurane anaesthesia. However, this does not exclude any possible physiological alterations. The aim of our study was to evaluate pulmonary inflammatory mediators in bronchoalveolar lavage (BAL) after sevoflurane and thiopentone anaesthesia in pigs with intact lungs.
Methods:  Sixteen pigs were randomly selected to receive either a continuous thiopentone infusion (control group, n = 8) or sevoflurane (n = 8) at 4.0% inspiratory concentration (1.5 MAC) in air for 6 h. Bronchoalveolar lavage samples were collected at the end of the study to determine pulmonary inflammatory markers.
Results:  Compared with thiopentone anaesthesia, significant increases in BAL leukotriene C₄ (LTC₄), NO₃-, and NO₂- levels were observed after sevoflurane anaesthesia. In addition, there was a significant decrease in total blood leukocyte count in sevoflurane-treated animals.
Conclusion:  We conclude that sevoflurane increases pulmonary LTC₄, NO₃-, and NO₂- production in pigs, indicating an inflammatory response.     

血小板源性伤口愈合因子对伤口组织细胞增殖作用的实验研究

为了观察不同浓度的血小板源性伤口愈合因子（ＰＤＷＨＦ）对伤口成纤维及表皮细胞增殖能力的影响，并探讨其可能的机理，利用离体培养的鼠伤口在纤维细胞及人伤口表皮细胞为模型，将培养细胞分为三组，空白对照组：基质处理组（ＢＭ，成分为１６４０＋０．５％ ＦＣＳ）；阳性对照组：１６４０＋１０％ＦＣＳ；ＰＤＷＨＦ组：ＢＭ＋１％ＰＤＷＨＦ、ＢＭ＋３％ＰＤＷＨＦ、ＢＭ＋５％ＰＤＷＨＦ、ＢＭ＋７％ＰＤＷＨＦ、ＢＭ＋１０     

成纤维细胞移植促进人工真皮内血管新生的研究

目的观察成纤维细胞与人工真皮共同移植对移植床及真皮海绵内微血管形成、胶原沉积的影响,促进人工真皮海绵内类真皮组织形成,缩短"二期植皮"的间隔时间.方法 Wistar大鼠18只,背部两侧各制作2.5 cm×2.5 cm全层皮肤缺损创面,在移植人工真皮之前分为两组,即成纤维细胞移植组(A组):向创面喷洒混入密度为1.0×105/cm2的同种真皮成纤维细胞的纤维蛋白胶0.5 ml;对照组(B组):只喷洒纤维蛋白胶0.5 ml.于移植后5和10天分别切取移植的真皮及周围组织,进行HE染色、Masson染色、VEGF免疫抗体染色和墨汁灌注染色,观察移植床及真皮海绵内微血管新生及胶原沉积状态;于移植后5天行伊文蓝组织灌注,分光光度计测定真皮海绵内染料含量,定量检测真皮海绵内循环渗透情况.结果移植后5天,新生血管主要集中在真皮下移植床,A组新生血管较B组明显增多,A组(9.64±2.36)个/高倍视野,B组(3.88±1.62)个/高倍视野,差异有统计学意义(P＜0.05);VEGF阳性细胞亦明显增多.移植后10天,移植床及真皮内均有微血管形成,A组血管数量和管径均较B组增加,胶原沉积量也明显增加.A组(46.04±8.90)个/高倍视野,B组(30.08±7.76)个/高倍视野,有统计学意义(P＜0.05).结论同种成纤维细胞移植可明显加快人工真皮内及移植床的血管新生和胶原沉积,加快真皮海绵内类真皮组织的形成.     

Dispersion of Pressure to the Head in Brain/NeuroSurgery

Skin and soft tissue defects are sometimes problematic especially when the defects large, contaminated, irradiated, or poor blood supplied. The human mesenchymal stem cells (hMSCs) are proliferated upon basic fibroblast growth factor (bFGF) stimuli in vitro and in vivo. In this experiment, the skin and soft tissue defects are investigated if the wounds are able to be reepithelialized or accelerated by hMSCs, bFGF and porcine‐derived bilayered skin template.
1.5 × 1.5 cm² nude rat skin and soft tissue defects including panniculus carnosus are excised and 1 × 10⁶ hMSCs and various doses of bFGF (1–100 μg) applied. Before and after normal reepithelialization, the tissues are tested for protein expressions by immunohistochemistry and Western blotting.
The wound sizes are significantly decreased at day 7 with hMSCs with 1, 10, or 100 μg bFGF compared to hMSCs‐alone or medium‐only. All the wounds healed by day 42. 42 Kda and 38 Kda human‐derived pancytokeratin expressions, which do not cross‐react with murine antigens, by Western blotting significantly augmented by 10 μg bFGF compared to hMSCs‐alone. The epidermal immunolocalizations such as integrin α3 and SKALP (Skin‐derived Anti Leukoproteinase) are greatly elevated in time and dose‐dependent manner. Human pan‐cytokeratin expressions are immunoreactive even at day 42.
These data suggest the skin and soft tissue wound healing is accelerated by hMSCs together with bFGF, partly by means of differentiation of hMSCs toward epidermal components.     

A serum amyloid P-binding hydrogel speeds healing of partial thickness wounds in pigs

During wound healing, some circulating monocytes enter the wound, differentiate into fibroblast-like cells called fibrocytes, and appear to then further differentiate into myofibroblasts, cells that play a key role in collagen deposition, cytokine release, and wound contraction. The differentiation of monocytes into fibrocytes is inhibited by the serum protein serum amyloid P (SAP). Depleting SAP at a wound site thus might speed wound healing. SAP binds to some types of agarose in the presence of Ca²⁺. We found that human SAP binds to an agarose with a K _D of 7 × 10⁻⁸ M and a B _max of 2.1 μg SAP/mg wet weight agarose. Mixing this agarose 1 : 5 w/v with 30 μg/mL human SAP (the average SAP concentration in normal serum) in a buffer containing 2 mM Ca²⁺ reduced the free SAP concentration to ∼0.02 μg/mL, well below the concentration that inhibits fibrocyte differentiation. Compared with a hydrogel dressing and a foam dressing, dressings containing this agarose and Ca²⁺ significantly increased the speed of wound healing in partial thickness wounds in pigs. This suggests that agarose/Ca²⁺ dressings may be beneficial for wound healing in humans.     

Tumor-infiltrating lymphocytes derived from human renal cell carcinoma: Clonal analysis of its characteristics

Aim:   To assess the characteristics of activated tumor-infiltrating lymphocytes (TIL), we report the isolation, growth response, and functional analysis of a CD4^- CD8⁺ TIL-clone derived from human renal cell carcinoma (RCC).
Methods:   Bulk TILs were expanded from a human RCC and the lymphocytes were separated into a CD8⁺ enriched population. Subsequently, using the limiting dilution technique, a TIL clone was established and its growth response, phenotype and cytotoxic activity were analyzed.
Results:   A clone, T16-13, by day 94 numbering 1 × 10⁷ cells, was harvested and characterized as a CD4^- CD8⁺ clone. On day 144, the cytotoxic activity of this clone against the autologous tumor was relatively high (2.3 ± 0.7 LU₃₀/10⁶ cells). Meanwhile, against allogeneic renal tumors, there was no cytotoxic activity (−0.1 LU₃₀/10⁶ cells).
Conclusions:   A TIL clone possessing modest autologous tumor-specific cytotoxicity can be isolated from human RCC. The characteristics analysis of various TIL clones may provide a better understanding of an RCC tumor microenvironment and may help to establish new modalities for the treatment of patients with metastatic kidney cancer.     

Effects of blood sample volume on hematocrit in critically ill children and neonates

Background:  There are no studies correlating the volume of blood taken from children and hematocrit (Hct) stability, relating those changes to duration of stay, severity of illness or weight. Earlier studies in neonates suggest that repeated sampling results in a drop in Hct.
Aim:  To characterize the changes in Hct in children of all ages admitted to intensive care over a 5-day period following routine blood volume sampling.
Methods:  We undertook an open prospective observational study. Eligible children were recruited sequentially and data recorded for 5 days following admission. The bedside nurse recorded the daily volume of blood samples taken and transfusions given. Daily Hct was noted from the routine full blood count. The relationship between changes in Hct and blood sample volume and transfusion requirement was studied.
Results:  There were no differences in mean Hct on admission at end of the study ( P  = 0.69, n  = 30) nor in the median blood volume sampled between transfused and nontransfused groups (7.5 ml·kg⁻¹ vs 7.9 ml·kg⁻¹, P  = 0.88). The largest blood sample volumes were taken on admission and from the smallest patients.
Conclusion:  We have quantitated the change in Hct and size of blood volume taken for routine laboratory studies. We suggest that children can tolerate 0.25 ml·kg⁻¹·day⁻¹ blood sampling without a fall in Hct and sampling can be tailored to the individual child according to the admission Hct.     

Photoselective vaporization of the prostate: Outcome according to the prostate size in a series of 102 Japanese patients

Objectives:   To identify the efficacy and safety of photoselective vaporization of the prostate (PVP) in relation to the prostate size in subjects with benign prostatic enlargement.
Methods:   The prospective study included 102 Japanese patients who underwent PVP. The efficacy and morbidity following PVP were compared in groups classified according to the baseline prostate size: prostates <40 cm³ (group 1, n  = 25), 40 cm³ ≤ prostates <80 cm³ (group 2, n  = 53), and 80 cm³ ≤ prostates (group 3, n  = 24). Each subgroup was assessed for the treatment efficacy in terms of peak urinary flow rate, post-void residual urine volume, International Prostate Symptom Score, and quality-of-life score at 3, 6 and 12 months after PVP.
Results:   Except for a difference in International Prostate Symptom Score (group 2 vs 3) and peak urinary flow rate (groups 1 vs 3) at 6 months after PVP, no significant differences were observed among the groups in the level of improvement in each outcome variable. The efficacy of vaporization was significantly lower in group 1 ( P  < 0.05, group 1 vs 2 or 3). The hemoglobin loss after PVP did not differ substantially among the groups. No statistically significant difference was found among the three groups regarding the total incidence of adverse events.
Conclusions:   PVP appears to be a safe and effective treatment for benign prostatic enlargement, irrespective of the prostate size.     

Efficacy of a low-dose spinal morphine with bupivacaine for postoperative analgesia in children undergoing hypospadias repair

Background:  Children undergoing hypospadias repair need to be protected from highly unpleasant sensory and emotional experiences during and after surgery. We designed a double-blinded, randomized, and placebo-controlled study to compare the efficacy of a low-dose (2 μg·kg⁻¹) of intrathecal morphine with placebo for postoperative pain control of children undergoing repair of hypospadias surgery with spinal anesthesia.
Methods:  Fifty-four children were randomly assigned to one of two spinal anesthesia groups. Group M ( n  = 27) received hyperbaric bupivacaine plus 2 μg·kg⁻¹ of preservative-free morphine and group P ( n  = 27) received hyperbaric bupivacaine plus 0.9% NaCl (placebo) under inhalation anesthesia. General anesthetics were discontinued subsequent to the block. The primary outcome was the presence of pain-requiring analgesics during the first 12 h after the spinal block. Side effects were also recorded. The analgesic effects were evaluated by using the Children's Hospital of Eastern Ontario Pain Scale.
Results:  Forty-nine patients completed the trial. Fifteen patients (60%) in group P received supplementary analgesics within the first 12 h compared to only four patients (16.7%) in group M ( P  = 0.005). Mean duration of analgesia was 480 ± 209 and 720 ± 190 min in group P and group M respectively ( P  = 0.009). The groups were similar in postoperative side effects.
Conclusion:  Spinal anesthesia provided by hyperbaric bupivacaine is adequate for distal hypospadias repair in children, but adding 2 μg·kg⁻¹ intrathecal morphine provides better postoperative pain control when compared to placebo in these children.     

Effect of different induction strategies on effector, regulatory and memory lymphocyte sub-populations in clinical islet transplantation

This prospective study assessed lymphocyte subsets in the peripheral blood of 42 islet allograft recipients using flow cytometry from 2 weeks and up to 2 years post-transplantation. Subjects received daclizumab ( n  = 16), Thymoglobulin ( n  = 12) or alemtuzumab ( n  = 14). Alemtuzumab was associated with an early (within 1 month) and transient (up to 6 months) increase in the frequency of CD3⁺ CD4⁺ Foxp3⁺ T cells, while daclizumab induced a near complete loss of these cells ( P  ≤ 0.001). The frequency of memory CD4⁺ T cells was increased following depleting immunosuppression induction with either Thymoglobulin or alemtuzumab ( P  ≤ 0.05), but remained unchanged while using daclizumab. Alemtuzumab induction resulted in a significant loss of memory B lymphocytes when compared with the other induction groups ( P  ≤ 0.001). While the clinical significance of these findings remains to be fully determined, the observed altered balance between effector, regulatory and memory cells suggests that the immune status of patients will be affected according to the induction strategy chosen.     

Effect of reactive oxygen species in semen on the pregnancy of infertile couples

Objective:   We intended retrospectively to investigate whether reactive oxygen species (ROS) levels, detected in whole semen, were correlated with the actual pregnancy rate.
Methods:   A total of 89 patients with data of ROS in semen, attending our male infertility clinics from April 1994 to June 2000, were evaluated. Semen parameters were determined with computer assisted semen analyzer (CASA) and ROS production levels were measured using a computer-driven LKB Wallac 1251 Luminometer after the addition of 40 µL of 4 mM luminol at the patients' first visits. All of the participants were inquired about their partners' pregnancies after the mean follow-up of 24.0 months (range 1.4 to 74.1). They were divided into two groups (pregnant group: n  = 41, non-pregnant group: n  = 48) and their characteristics, semen profiles and integrated ROS levels were analyzed.
Results:   There was no difference between the pregnancy rate of ROS detectable cases and negative cases. However, the mean integrated ROS level in detectable cases of the non-pregnant group was significantly higher than that in detectable cases of the pregnant group (115.61 ± 74.32 mV/30 min/10⁶ sperm versus 7.22 ± 4.69 mV/30 min/10⁶ sperm, P  = 0.0033). Then, by calculating the receiver operating characteristics curve with 95% confidence intervals, 4.35 mV/30 min/10⁶ sperm was considered as a cut-off value of ROS in semen for pregnancy.
Conclusion:   These results indicate that (i) highly detectable ROS in whole semen of infertile patients may have implications in their partners' pregnancies and that (ii) detection of ROS in whole semen has a prognostic value for idiopathic male infertility.     

004Topical Zinc Oxide for Open Pilonidal Wounds

Extended healing time and lack of documented effective treatments of sacrococcygeal pilonidal disease create substantial problems. Locally applied zinc oxide has been reported to promote wound healing. We have compared topical zinc oxide (3%) with placebo meshes for pilonidal wounds healing by secondary intention in a randomized, double‐blind, placebo‐controlled multicenter trial. Sixty‐four consecutive patients, 53 males, aged between 18 and 60 years (median 26 years) with excised pilonidal wounds were centrally randomized to local zinc oxide (30 mg/g, n = 33) or to placebo (n = 31) mesh treatment. Patients were followed with strict recording of beneficial and harmful effects. The median healing times were 54 days (42–71 days, interquartile range, n = 33) for the zinc group and 62 days (55–82 days, n = 31) for the placebo group. This difference was not statistically different (p = 0.32). Based on Cox regression analysis initial wound volume influenced healing negatively (p = 0.016) while smoking (p = 0.011) was associated with faster wound healing. Significantly (p < 0.01) more placebo (n = 12) than zinc oxide‐treated patients (n = 3) needed antibiotics postoperatively. Although topical zinc oxide increased (p < 0.001) wound fluid zinc levels (1830 ± 405 μM, mean ± SEM) compared with placebo (3.1 ± 1.6 μM) serum‐zinc levels did not differ significantly between the zinc (13.5 ± 0.4 μM) and placebo (12.8 ± 0.4 μm) groups on postoperative day 7. No adverse events were recorded. Topical zinc oxide treatment did not accelerate time to closure of open pilonidal wounds but was associated with reduced antibiotic usage.     

Alterations of bacterial clearance induced by propofol

Background: The purpose of the study was to investigate the potential influence of the anaesthetic agent propofol on immune function in terms of systemic clearance and organ distribution of injected Escherichia coli in a rabbit model.
Methods: Defined numbers of E. coli (1.3×10⁸ colony-forming units, CFU) were injected intravenously 1 h after starting a 4-h infusion of the anaesthetic propofol (2 ml  ·  kg⁻¹  ·  h⁻¹, Disoprivan^® 1%; n=6)) or after saline application (n=6). As propofol is formulated in a 10% lipid emulsion, the lipid vehicle Intralipid^® (2 ml  ·  kg⁻¹  ·  h⁻¹; n=6) alone was investigated in a separate group. Parameters monitored were arterial pressure and rates of bacterial elimination from the blood. Three hours after bacterial injection, the animals were killed, and tissue samples of liver, spleen, lung, and kidney were collected for microbiological examinations.
Results: Compared to saline-treated animals, infusion of propofol induced increased accumulation of E. coli in lung and spleen, thus reflecting reticuloendothelial system dysfunction.
Conclusion: As the lipid emulsion by itself induced the same effects, the impaired immune function due to propofol is thought to be attributed to its solvent Intralipid^®.