Afferent vagal stimulation via gastric electrical stimulation alters sympathetic-vagal balance in domestic pigs - a pilot trial.

The disturbance of the sympathetic-vagal balance with increasing sympathetic activity and consecutive increase in cytokine release is a major threat in numerous hyperinflammatory syndromes. Therapeutic interventions that modulate the activity in the sympathetic-vagal system are suggested as an effective treatment in these incidences. The purpose of this pilot study was to investigate the effect of electrical stimulation of the gastric wall on sympathetic-vagal balance. German domestic pigs (n=5) were prepared with a modified gastric tube (mGT) for repetitive gastric electrical stimulation (GES). Electrocardiogram was recorded continuously and heart rate variability (HRV) as measure of sympathetic-vagal activity was calculated for three-minute epochs at baseline condition before GES and during GES condition. In comparison to baseline, activity of the autonomic nervous system (ANS) shifted significantly toward increased dominance of vagal activity during GES with a decrease of normalized low frequency (nLF from 58.00 to 25.52) as marker of sympathetic dominance and parallel increase of normalized high frequency (nHF from 41.48 to 74.16) as marker of vagal dominance. During GES, compared to baseline, no difference in heart rate was found. These results indicate that electrical stimulation of the gastric wall may result in shifting the sympathetic-vagal balance toward a parasympathetic predominance.

A four-parameter system for rationalising the electronic properties of transition metal-radical ligand complexes.

A system of four principal parameters is reported that provides a unified description of the electronic and chemical properties of radical-ligand coordination compounds. This type of parametrisation applies to compositionally different types of radical-ligands, and the principal parameters rank in the following order: (a) coordination mode (metal-ligand orbital alignment) > (b) metal linkage > (c) ligand charge > (d) geometric strain (on orbital overlap). A series of group-10 metal complexes of an open-shell thiolate-arene-thiolate ligand suits to differentiate between three of the four effects in a clear-cut fashion, which allowed sorting these into a semi-quantitative order for the first time. Combined experimental and TD-DFT data aided in distinguishing structural effects from metal specific contributions such as relativistic effects. The applicability of spectroscopic and structure properties to serve as characteristic markers for comparison is discussed with regard to the large body of planar radical-ligand structures.

Coordination chemistry of stannylene-based Lewis pairs - insertion into M-Cl and M-C bonds. From base stabilized stannylenes to bidentate ligands.

The coordination chemistry of intramolecular stannylene phosphorus Lewis pairs incorporated into four membered ring systems is presented. Previously reported coordination chemistry of stannylene and phosphorus towards palladium(0) is extended by using Pd(nbe)3 as a precursor, yielding co-ligand free complexes. An equilibrium of one or two stannylene phosphorus ligands coordinated to Pd(0) was observed with tin acting either as a donor or an acceptor towards palladium. Furthermore, the reactions with transition metal(i) chlorides, [(cod)IrCl]2, [(cod)RhCl]2 and Me2SAuCl are reported. They proceed via insertion of stannylene into the M-Cl bonds, yielding metal complexes with chelating stannide phosphorus ligands. For gold, a dinuclear complex with bridging P-Sn ligands was formed. Furthermore, the reaction of a P → Sn Lewis pair in a three membered ring system with (cod)PtMe2 is reported.

Estradiol prodrugs (EP) for efficient oral estrogen treatment and abolished effects on estrogen modulated liver functions.

Oral compared to parenteral estrogen administration is characterized by reduced systemic but prominent hepatic estrogenic effects on lipids, hemostatic factors, GH-/IGF I axis, angiotensinogen. In order to avoid such adverse metabolic effects of oral treatment, estradiol (E2) prodrugs (EP) were designed which bypass the liver tissue as inactive molecules. Carbone17-OH sulfonamide [-O2-NH2] substituted esters of E2 (EC508, others) were synthesized and tested for carbonic anhydrase II (CA-II) binding. CA II in erythrocytes is thought to oppose extraction of EP from portal vein blood during liver passage. Ovariectomized (OVX, day minus 14) rats were orally treated once daily from day 1-3. Sacrifice day 4. Uteri were dissected and weighed. Cholesterol fractions and angiotensinogen were determined in plasma. Oral E2 and ethinyl estradiol (EE) generated dose related uterine growth and important hepatic estrogenic effects. EP induced uterine growth at about hundred-fold lower doses. This was possible with almost absent effects on plasma cholesterol or angiotensinogen. Preliminary pharmacokinetic studies with EC508 used intravenous and oral administration in male rats. Resulting blood levels revealed complete oral bioavailability. Further high blood- but low plasma concentrations indicated erythrocyte binding of EC508 in vivo as potential mechanism of low extraction at liver passage. Very high systemic estrogenicity combined with markedly lower or absent adverse hepatic estrogenic effects is evidence for a systemic release of E2 from sulfonamide EP. In conclusion, tested oral EP bypass the liver in erythrocytes furnishing systemic estradiol at hydrolysis. This mechanism avoids the hepatic estrogenic impact of conventional oral estrogen therapy.

Development of somatosensory-evoked potentials in foetal sheep: effects of betamethasone.

AIM: Antenatal glucocorticoids are used to accelerate foetal lung maturation in babies threatened with premature labour. We examined the influence of glucocorticoids on functional and structural maturation of the central somatosensory pathway in foetal sheep. Somatosensory-evoked potentials (SEP) reflect processing of somatosensory stimuli. SEP latencies are determined by afferent stimuli transmission while SEP amplitudes reveal cerebral processing. METHODS: After chronic instrumentation of foetal sheep, mothers received saline (n = 9) or three courses of betamethasone (human equivalent dose of 2 × 110 µg kg-1 betamethasone i.m. 24 h apart, n = 12) at 0.7, 0.75 and 0.8 of gestational age. Trigeminal SEP were evoked prior to, 4 and 24 h after each injection and at 0.8 of gestational age before brains were histologically processed. RESULTS: Somatosensory-evoked potentials were already detectable at 0.7 of gestation age. The early and late responses N20 and N200 were the only reproducible peaks over the entire study period. With advancing gestational age, SEP latencies decreased but amplitudes remained unchanged. Acutely, betamethasone did not affect SEP latencies and amplitudes 4 and 24 h following administration. Chronically, betamethasone delayed developmental decrease in the N200 but not N20 latency by 2 weeks without affecting amplitudes. In parallel, betamethasone decreased subcortical white matter myelination but did not affect network formation and synaptic density in the somatosensory cortex. CONCLUSION: Somatosensory stimuli are already processed by the foetal cerebral cortex at the beginning of the third trimester. Subsequent developmental decrease in SEP latencies suggests ongoing maturation of afferent sensory transmission. Antenatal glucocorticoids affect structural and functional development of the somatosensory system with specific effects at subcortical level.

Gentamicin coating of plasma chemical oxidized titanium alloy prevents implant-related osteomyelitis in rats.

Implant related infection is one of the most feared and devastating complication associated with the use of orthopaedic implant devices. Development of anti-infective surfaces is the main strategy to prevent implant contamination, biofilm formation and implant related osteomyelitis. A second concern in orthopaedics is insufficient osseointegration of uncemented implant devices. Recently, we reported on a macroporous titanium-oxide surface (bioactive TiOB) which increases osseointegration and implant fixation. To combine enhanced osseointegration and antibacterial function, the TiOB surfaces were, in addition, modified with a gentamicin coating. A rat osteomyelitis model with bilateral placement of titanium alloy implants was employed to analyse the prophylactic effect of gentamicin-sodiumdodecylsulfate (SDS) and gentamicin-tannic acid coatings in vivo. 20 rats were randomly assigned to four groups: (A) titanium alloy; PBS inoculum (negative control), (B) titanium alloy, Staphylococcus aureus inoculum (positive control), (C) bioactive TiOB with gentamicin-SDS and (D) bioactive TiOB plus gentamicin-tannic acid coating. Contamination of implants, bacterial load of bone powder and radiographic as well as histological signs of implant-related osteomyelitis were evaluated after four weeks. Gentamicin-SDS coating prevented implant contamination in 10 of 10 tibiae and gentamicin-tannic acid coating in 9 of 10 tibiae (infection prophylaxis rate 100% and 90% of cases, respectively). In Group (D) one implant showed colonisation of bacteria (swab of entry point and roll-out test positive for S. aureus). The interobserver reliability showed no difference in the histologic and radiographic osteomyelitis scores. In both gentamicin coated groups, a significant reduction of the histological osteomyelitis score (geometric mean values: C = 0.111 ± 0.023; D = 0.056 ± 0.006) compared to the positive control group (B: 0.244 ± 0.015; p < 0.05) was observed. The radiographic osteomyelitis scores confirmed these histological findings.

[Potential of Information and Communications Technology to Improve Intersectoral Processes of Care: A Case Study of the Specialised Outpatient Palliative Care]. / Potenziale der Informations- und Kommunikationstechnologie zur Optimierung intersektoraler Versorgungsprozesse: Ein Fallbeispiel der spezialisierten ambulanten Palliativversorgung.

OBJECTIVE: The added value of information and communications technologies should be demonstrated precisely in such areas of care in which the importance of intersectoral and interdisciplinary cooperation is particularly high. In the context of the accompanying research of a supply concept for palliative care patients, the potential of a digital documentation process was comparatively analysed with the conventional paper-based workflow. METHODS: Data were collected in the form of a multi-methodological approach and processed for the project in 3 stages: (1) Development and analysis of a palliative care process with the focus on all relevant steps of documentation. (2) Questionnaire design and the comparative mapping of specific process times. (3) Sampling, selection, and analysis of patient records and their derivable insights of process iterations. RESULTS: With the use of ICT, the treatment time per patient is reduced by up to 53% and achieves a reduction in costs and workload by up to 901 min. The result of an up to 213% increase in the number of patient contacts allows a higher continuity of care. Although the 16% increase in documentation loyalty improves the usability of cross-team documented information, it partially extends the workload on the level of individual actors. By using a digital health record around 31% more patients could be treated with the same staffing ratio. CONCLUSIONS: The multi-stage analysis of the palliative care process showed that ICT has a decisive influence on the process dimension of intersectoral cooperation. Due to favourable organisational conditions the pioneering work of palliative care also provides important guidance for a successful use of ICT technologies in the context of innovative forms of care.

A bidentate boryl ligand: syntheses of platinum and iridium complexes.

A methylenediphenylphosphine substituted diazaborole was obtained in a two-step procedure in amounts around 4 g. This B-P ligand was coordinated at platinum and iridium and the structures of the boryl complexes are discussed. In the case of the iridium derivative an interesting boron-boron contact was found.

Short communication: Effects of analgesic use postcalving on cow welfare and production.

The aim of this study was to assess the welfare and production of cows given an analgesic drug (carprofen, 1.4 mg/kg i.v.) within 6h after calving. The study was performed in a dairy farm with approximately 1,000 milking cows. Behavior, clinical indices, and production data (milk yield and fertility) of cows treated with carprofen (n = 19) or a placebo (n = 20) were compared. Additionally, differences related to parity (primiparous vs. multiparous) were analyzed. No significant differences were observed in the time of placental expulsion or incidence of clinical disease over the 3 d postpartum, but more animals from the analgesia group were observed eating during the first hours after calving.For unassisted calvings, the rectal temperature 24h postpartum was lower in the cows given analgesic. Total lactation yields at 305 d in milk were higher in the primiparous cows treated with carprofen. Fewer cows were pregnant at 220 d postpartum in the treated group as the use of carprofen increased the time from calving to conception. This study suggests that pain management after parturition leads to earlier feed intake after calving and that this may lead to higher milk yield in first-lactation animals.

[Soft tissue reconstruction in the extremities and the head and neck area using the anterolateral thigh free flap]. / Die freie anterolaterale Oberschenkellappenplastik zur Weichteilrekonstruktion an den Extremitäten und im Kopf-Hals-Bereich.

OBJECTIVE: Stable soft tissue coverage of exposed bone, tendons, or hardware in the extremities or the head and neck area with a microsurgically grafted free flap. INDICATIONS: Soft tissue defects measuring up to 42 × 15 cm in the extremities and the head and neck region. CONTRAINDICATIONS: Previous surgery or trauma in the anterolateral thigh region. Insufficient personnel and/or technical resources. SURGICAL TECHNIQUE: A line is marked from the anterior superior iliac spine to the superolateral patella pole, approaching the intermuscular septum between the rectus femoris and vastus lateralis muscle. The flap is centred on this line and after medial incision the perforators of the descending branch of the lateral circumflex femoral artery are identified and dissected to their origin. Afterwards the lateral incision is carried out and flap dissection is completed. After flap transfer microsurgical anastomoses are performed and the flap is sutured to the recipient region. POSTOPERATIVE MANAGEMENT: Flap monitoring for 1 week. Strict elevation and immobilization after flap transfer to the extremities; bedrest for 1 week. Thrombosis prophylaxis. RESULTS: From 2008-2011, 41 free anterolateral thigh flaps in 5 women and 36 men with an average age of 53 years (38-70 years) were performed for microsurgical soft tissue reconstruction. Total flap loss rate was 2.4 % and reoperation due to complications, e.g., hematoma, problems with microsurgical anastomosis, and partial flap loss was necessary in 13.8 % of patients.

Breast cancer management and outcome according to surgeon's affiliation: a population-based comparison adjusted for patient's selection bias.

BACKGROUND: Studies have reported that breast cancer (BC) units could increase the quality of care but none has evaluated the efficacy of alternative options such as private BC networks, which is our study objective. PATIENTS AND METHODS: We included all 1404 BC patients operated in the public unit or the private network and recorded at the Geneva Cancer Registry between 2000 and 2005. We compared quality indicators of care between the public BC unit and the private BC network by logistic regression and evaluated the effect of surgeon's affiliation on BC-specific mortality by the Cox model adjusting for the propensity score. RESULTS: Both the groups had high care quality scores. For invasive cancer, histological assessment before surgery and axillary lymph node dissection when indicated were less frequent in the public sector (adjusted odds ratio (OR): 0.4, 95% confidence interval (CI) 0.3-0.7, and OR: 0.4, 95% CI 0.2-0.8, respectively), while radiation therapy after breast-conserving surgery was more frequent (OR: 2.5, 95% CI 1.4-4.8). Surgeon affiliation had no substantial effect on BC-specific mortality (adjusted hazard ratio (HR): 0.8, 95% CI 0.5-1.4). CONCLUSIONS: This study suggests that private BC networks could be an alternative to public BC units with both structures presenting high quality indicators of BC care and similar BC-specific mortality.

[Split thickness skin graft for coverage of soft tissue defects]. / Spalthauttransplantation zur weichteildefektdeckung.

OBJECTIVE: Coverage of skin or soft tissue defects of various sizes by transplantation of spit thickness skin grafts. INDICATIONS: Skin or soft tissue defects of any size or location as long as there is a good blood supply to the wound bed. CONTRAINDICATIONS: Wound bed providing poor blood supply (e.g., tendon or bone), vessels or nerve without soft tissue coverage, any kind of implant material which is not covered by vital soft tissue. Relative contraindications include defect position at the flexion side of joints or other mechanically stressed locations (e.g., heel, neck) and local infection. SURGICAL TECHNIQUE: By meticulous debridement of the recipient site and coagulation of venous bleedings, the recipient site is prepared for skin grafting. Thereafter, the split thickness skin graft is harvested and, if necessary, modified by the meshing procedure. Then, the skin graft is placed in the defect and fixated at the wound margins. To promote healing, a special compression dressing is used to cover the split thickness skin graft. In case of uneventful wound healing, this dressing should be left in place for 5 days. POSTOPERATIVE MANAGEMENT: After removal of the compression dressing, daily changes are done using double layers of fatty gauze, alternated with periods without dressing. In the case of uneventful healing, the skin transplant can be covered starting in week 2 with a thin film of cream ointment. RESULTS: Split thickness skin grafting is a routine maneuver in reconstructive surgery and allows predictable, good results. Partial skin graft losses are mostly due to a combination of inadequate debridement and local infection. If the operation in done technically correct, total graft losses are rare.

[Special training therapy to reduce inflammation in Anti-Jo-1 syndrome]. / Spezielle Trainingstherapie zur Reduktion der Inflammation bei Anti-Jo-1-Syndrom.

A 46-year-old patient was frequently seen with a medically treated Anti-Jo-1 syndrome. The patient had already been treated with azathioprine and oral corticosteroids on account of decreasing lung function, dyspnoea, fatigue, and beginning signs of myositis. Although high doses of steroids and azathioprine were administered, the muscleskeletal syndromes increased steadily. The patient used to be an active long-distance runner (20 km), but now was unable to perform that kind of physical exercise. It was decided to start a treatment with the GalileoTM training device for active muscle training of the lower extremities. Before and after three months of training the following assessment was performed: measurement of health-related quality of life (St. Georges respiratory questionnaire, SGRQ), ultrasound measurement of the cross-sectional area of the quadriceps muscle, 6 minute walk test (6 MWT), lung function testing, and assessment of serum markers of inflammation (TNF-alpha, interleukin-8, CRP, CK, myoglobin). After only two months, training with the GalileoTM five times a week has improved the patient's conditions dramatically. The training will be continued.

[The anterolateral thigh flap: its versatility in oncological soft tissue reconstruction of the head and neck region]. / Der anterolaterale Oberschenkellappen : Seine Vielseitigkeit bei der onkologischen Weichteilrekonstruktion im Kopf-Hals-Bereich.

The anterolateral thigh flap (ATL) has become a standard procedure in reconstructive microsurgery. In this study the results with the ALT for reconstruction in the head and neck area after tumor resection in 33 patients were retrospectively analyzed. Patients included 28 men and 5 women aged 47-70 years who suffered from intraoral and extraoral tumors. Satisfactory soft tissue coverage could be achieved in all patients and no flaps were lost. The ALT is a versatile free flap enabling reliable soft tissue reconstruction of complex defects in the head and neck region. Flap dissection and preparation of the recipient area can usually be performed simultaneously. Additional advantages include the long and strong caliber vascular pedicle, the low donor site morbidity and the different possibilities of tissue composition, making the ALT a workhorse flap in modern reconstructive microsurgery.

Three-dimensional visualization of in vitro cultivated chondrocytes inside porous gelatine scaffolds: A tomographic approach.

Synchrotron radiation-based microcomputed tomography (SR-microCT) has become a valuable tool in the structural characterization of different types of materials, achieving volumetric details with micrometre resolution. Biomedical research dealing with porous polymeric biomaterials is one of the research fields which can benefit greatly from the use of SR-microCT. This study demonstrates that current experimental set-ups at synchrotron beamlines achieve a sufficiently high resolution in order to visualize the positions of individual cartilage cells cultivated on porous gelatine scaffolds made by a freeze-structuring technique. Depending on the processing parameters, the pore morphology of the scaffolds investigated was changed from large-pore sized but non-ordered structures to highly directional and fine pored. The cell-seeded scaffolds were stained with a combined Au/Ag stain to enhance the absorption contrast in SR-microCT. While only some cells showed enhanced absorption contrast, most cells did not show any difference in contrast to the surrounding scaffold and were consequently not detectable using conventional greyscale threshold methods. Therefore, using an image-based three-dimensional segmentation tool on the tomographic data revealed a multitude of non-stained cells. In addition, the SR-microCT data were compared with data obtained from scanning electron microscopy, energy dispersive X-ray spectroscopy and histology, while further linking the initial cell density measured via a MTT assay to the pore size as determined by SR-microCT.

[Ginkgo biloba extract EGb 761 in the treatment of dementia: evidence of efficacy and tolerability]. / Ginkgo-Spezialextrakt EGb 761(R) in der Behandlung der Demenz: Evidenz für Wirksamkeit und Verträglichkeit.

The Ginkgo biloba extract EGb 761 interferes with pathomechanisms relevant to dementia, such as Abeta aggregation, mitochondrial dysfunction, insulin resistance, and hypoperfusion. The efficacy of EGb 761 in the treatment of dementia (Alzheimer's disease and vascular dementia) has been studied in 10 randomised, controlled, double-blind clinical trials. In three of the four large trials conducted in accordance with recent recommendations EGb 761 was significantly superior to placebo with respect to cognitive performance and one or more further (global, functional or behavioural) outcomes demonstrating the clinical relevance of the findings. The findings from the six smaller trials are in line with those of the large trials. One trial was inconclusive, but of questionable external validity due to uncommonly rigorous patient selection. Subgroup analyses of this study together with the findings from the most recent clinical trial suggest that EGb 761 may be most beneficial to patients with neuropsychiatric symptoms, who actually constitute the majority of dementia patients. Delay in symptom progression, rates of clinically significant treatment response and numbers needed to treat (NNT) found for EGb 761 are in the same range as those reported for cholinesterase inhibitors. In an exploratory trial comparing EGb 761 and donepezil, no statistically significant or clinically relevant differences were seen. Hence, EGb 761 has its place in the treatment of dementia.

Retinotomy and silicone oil for detachments complicated by anterior inferior proliferative vitreoretinopathy.

AIM: To describe a subset of patients with recurrent retinal detachments caused by anterior intraretinal and subretinal proliferative vitreoretinopathy (PVR), which required greater than 180 degrees retinotomy and silicone oil tamponade. METHODS: Interventional case series. Forty-one patients underwent >180 degrees retinotomy, anterior retinectomy, removal of subretinal membranes, laser to the retinotomy edge and silicone oil tamponade. Risk factors for detachment, prior surgical history and PVR location were examined. Main outcomes included change in visual acuity, recurrent detachment and postoperative complications. RESULTS: Cataract extraction (49%), high myopia (29%) and lattice degeneration (27%) were preoperative risk factors. The average number of prior procedures for retinal attachment was 2.3 (SD 0.9). The majority of detachments were inferior and related to anterior intraretinal and subretinal PVR. Twenty-four patients (59%) saw 20/200 or better. Eleven patients (27%) had poor vision (<20/400) at the end of follow-up. Thirty-seven retinas (90%) remained attached. Increased rates of postoperative corneal decompensation (p<0.0001) and silicone oil in the anterior chamber (p<0.0001) were statistically significant markers of poor visual outcome. CONCLUSIONS: Patients with complex PVR requiring a large retinotomy often had similar presurgical conditions. A large inferior retinotomy effectively addressed proliferations where they most frequently occur, and silicone oil was beneficial.

[On the comprehensibility of German hospital quality reports: systematic evaluation and need for action]. / Zur Verständlichkeit der Qualitätsberichte deutscher Krankenhäuser: Systematische Auswertung und Handlungsbedarf.

OBJECTIVE: This paper focuses on the current resolutions for quality reports of German hospitals as released in 2007 as well as on comprehensibility of these reports for patients. It is meant to analyse the textual information given by these quality reports. Its main objective was to attain a reliable assessment of their comprehensibility for patients on the basis of objective measuring methods. A further goal was to qualify eventual differences between large and small or private and public hospital operators. On the basis of the attained results conclusions on the appropriateness of the current legal situation and the existing criteria for quality reports were to be drawn. METHOD: The textual system part of 200 German hospital reports was analysed as published in the Internet (latest download 28th May, 2007). The selection took place by means of a controlled sample. The sample structure essentially corresponds to the German hospital system structure in terms of bed numbers and its ratio of public and private operators. The analysis measured all formal text patterns as well as technical terms by means of a computer-aided device. The readability index for each text was calculated according to all known readability formulas for the German language. RESULTS: German hospital quality reports are readable only for those patients who dispose of above-average communicative skills. The analysed reports contain more than 10% technical terms while 17% of the chosen words and 60% of all sentences are too long. 10% of all sentences are too complex and 25% comprise more than three technical terms. To understand these texts at least an entrance qualification for higher education is required in accordance to readability indices. The texts' degree of complexity is comparable to that of philosophical papers. Most textual information given by German hospital quality reports is proven to be unreadable and incomprehensible for most patients. There are no fundamental differences concerning hospital size and operator. CONCLUSIONS: The reports' readability and comprehensibility for patients have only scarcely been considered in the current legal resolutions, and there is no undergoing process of improvement. The analysis has shown that there is in fact an urgent need for action. Future reports should therefore ensure that their textual content is formulated in a readable and comprehensible recipient-friendly manner. To enhance customer-oriented transparency within the German public health service patients should be able to fully understand what hospitals want to communicate. Therefore the further process of research will focus on the development of specific criteria for the production of textual reports. This has to be done in co-operation with patients and resident general practitioners.

Consequences of one-lung flooding: a histological and immunological investigation.

BACKGROUND: Videothoracoscopic lung sonography after partial fluid instillation could be a new method for endoscopic detection of lung lesions. Histopathological consequences of unilateral diagnostic or therapeutic lung flooding under bronchoalveolar lavage has yet to be defined. The aim of the study was to investigate histological and immunohistological alterations induced by one-lung flooding (OLF). METHODS: 13 female pigs were subjected to OLF (15 ml isotonic electrolyte solution per kg for 60 minutes), and lung tissue was collected 30 minutes, 2 hours, 24 hours, 48 hours, 6 days, 8 days, and 10 weeks after flooding. Histological examinations and immunohistochemical labeling for surfactant protein A (SP-A) were performed. Cellular proliferation was measured by Ki67 immunohistochemical labeling. Apoptosis was detected through enzymatic in-situ labeling of apoptosis-induced DNA strand breaks by means of the TUNEL (TdT-mediated dUTP nick end labeling) method. RESULTS: Histological analyses revealed the presence of inflammatory cell infiltrates in the interstitium at 24 hours after OLF. However, no destruction of the alveolar wall and no pulmonary oedema were observed. In addition, OLF was not associated with any decrease in surfactant protein A immunoreactivity. Two hours after OLF, the number of apoptotic cells was increased (OLF: 7% vs. CONTROL: 0.6%, p < 0.05), but cellular proliferation was unchanged. Conversely, at 48 h after OLF, the number of apoptotic cells had returned to control levels, but cellular proliferation had increased (OLF: 5% vs. CONTROL: 1.1%, p < 0.05). Cellular proliferation returned to baseline levels eight days after OLF. CONCLUSIONS: These data demonstrate that OLF is not associated with destruction of the alveolar texture, atelectasis-provoking surfactant loss, or any irreversible damage to the pulmonary parenchyma. Lung flooding for the purpose of videothoracoscopic lung sonography is safe and justifiable. But repeated lung flooding under bronchoalveolar lavage involving the same lung area within 1 week is not to be recommended.