Evolution of magnetic surfboards and spin glass behavior in (Fe1-pGap)2TiO5

The unusual anisotropy of the spin glass (SG) transition in the pseudobrookite system Fe2TiO5has been interpreted as arising from an induced, van der Waals-like, interaction among magnetic clusters. Here we present susceptibility (χ) and specific heat data (C) for Fe2TiO5diluted with non-magnetic Ga, (Fe1-pGap)2TiO5, for disorder parameterp= 0, 0.11, and 0.42, and elastic neutron scattering data forp= 0.20. A uniform suppression ofTgis observed upon increasingp, along with a value ofχTgthat increases asTgdecreases, i.e.dχ(Tg)/dTg<0We also observeCT∝T2in the low temperature limit. The observed behavior places (Fe1-pGap)2TiO5in the category of a strongly geometrically frustrated SG.

Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

Genetic aspects for the behaviour of lactating sows towards humans

With the keeping of lactating sows in loose housing systems, ensuring work safety for stockpersons is gaining importance. Aim of the present study was to develop tests characterising the behaviour of lactating sows in farrowing environments with more freedom to move. The behaviour towards humans in different management procedures was examined. Emphasis was given to integrate tests into daily routines. The study was conducted in a nucleus herd with 771 purebred Landrace sows. Data were collected from October 2016 until December 2018. Sows were kept in individual indoor pens with movable farrowing crates in which the animals were restrained from 7 days antepartum (ap) to an average of 7 days postpartum (pp). The Dummy Arm Test (DAT; 1444 observations) was used to assess the sows' reaction towards a stockperson handling the piglets around day 4 pp (closed crates). With the Towel Test (TT; 2846 observations), the reaction of sows to a novel object and an unexpected situation was assessed. The Trough Cleaning Test (TCT; 2805 observations) described the sows' response to common procedures such as trough cleaning. TT and TCT were conducted on days 3 pp (closed crates) and 10 pp (open crates). Variance components of behavioural traits were estimated univariately with a linear animal model, and genetic correlations between traits were derived using a multivariate animal model in ASreml 3.0. Most sows showed no or only a slight reaction to human interactions without attempting to attack them. However, a strong defensive reaction of sows was recorded in 4.0% (TCT), 4.5% (TT), and 10.7% (DAT) of observations. This behaviour of sows was observed more frequently in the open than in the closed pen system. Estimates of heritabilities (h² ± SE) were h² = 0.17 ± 0.05 for behaviour of sows towards humans (DAT), h² = 0.19 ± 0.04 for response of sows towards unexpected situations (TT), and h² = 0.13 ± 0.04 for reactions of animals to TCT. Genetic correlations (r_g ± SE) ranged from r_g = 0.59 ± 0.37 between TT and TCT to r_g = 0.77 ± 0.30 between TT and DAT. Our results show that the developed tests are suitable for assessing the behaviour of sows towards humans. Behavioural traits derived from these tests could be used as new phenotypes for the genetic selection of gentle and easy-to-handle sows. The genetic correlations of all tests studied were positive indicating related reaction patterns.

Effect of SARS-CoV-2 vaccine on the breastmilk antibody response among lactating healthcare workers

In 2019, a deadly virus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for COVID-19, emerged. Two mRNA-based COVID-19 vaccines were approved for use in December 2020 in the US and have begun providing immunity to those receiving the vaccination. Certain vaccines given to pregnant and lactating mothers provide immunity to infants through transmission across the placenta and umbilical cord (IgG) and breast milk (IgA). Breastmilk produced by mothers with a history of COVID-19 infection has found to be a source of anti-SARS-CoV-2 IgA and IgG. This study aimed to determine the presence of specific SARS-CoV-2 IgA in the breastmilk of lactating women after the COVID-19 vaccine administration. As such, lactating healthcare workers who received the SARS-CoV-2 mRNA vaccine (Pfizer-BioNtech or Moderna) made up a sample group. Plasma and breast milk were collected at three time points (pre-vaccination, 14–28 days post first dose of vaccine, and 7 days post second dose of vaccine). SARS-CoV-2 specific IgA (breastmilk) and IgG (plasma) concentration were then measured by ELISA. We found consistent secretion of SARS-CoV-2 specific IgA in breast milk after COVID-19 vaccination. The second dose of the SARS-CoV-2 vaccine was necessary to elicit IgA response in breastmilk detectable by ELISA. There is a correlation of the level of SARS-CoV-2 specific IgG in blood with SARS-CoV-2 specific IgA in breastmilk. Our results show that the mRNA-based COVID-19 vaccines from Pfizer-BioNTech and Moderna induce SARS-CoV-2 specific IgA secretion in breastmilk. Further studies are needed to determine the duration of this immune response and a possible passive immunity transfer of SARS-CoV-2 specific IgA to breastfeeding infants.

[Bilateral vocal cord paresis after total thyroidectomy]

A 66-year-old female patient complained of hoarseness and dyspnea under exertion following total thyroidectomy. Due to a faulty operating technique both nerves to the vocal cords were damaged. From the operation report it emerged that the dissection was carried out by protecting the border lamellae but the recurrent laryngeal nerve could not be found on both sides. This article presents the external expert opinion, the decision of the arbitration board and the assessment of the case by two specialist physicians.

[Acute compartment syndrome after a bowling game]

A 28-year-old male patient was initially conservatively treated by a general physician for muscle strain of the right calf after a bowling game. Due to increasing pain and swelling of the lower leg 5 days later, the differential diagnosis of a deep vein thrombosis was considered. Furthermore, the onset of neurological deficits and problems with raising the foot prompted inclusion of compartment syndrome in the differential diagnosis for the first time. Admission to hospital for surgical intervention was scheduled for the following day. At this point in time the laboratory results showed a negative d-dimer value and greatly increased C-reactive protein level. On day 6 a dermatofasciotomy was performed which revealed extensive muscular necrosis with complete palsy of the peroneal nerve. In the following lawsuit the patient accused the surgeon of having misdiagnosed the slow-onset compartment syndrome and thus delaying correct and mandatory treatment. The arbitration board ruled that the surgeon should have performed fasciotomy immediately on day 5 at the patient's consultation. The clinical presentation of progressive pain, swelling of the lower leg in combination with peroneal palsy must lead to the differential diagnosis of compartment syndrome resulting in adequate therapy. The delay of immediate surgery, therefore, was assessed to be faulty as this knowledge is to be expected of a surgeon.

[High-pressure injection injury of the hand. Underestimation of injury severity]

A 44-year-old man sustained a high-pressure injection injury of the left index finger with hot hydraulic oil in an occupational accident. On presentation to the occupational physician 4 h later the wound was irrigated and cleaned. At this time X-ray diagnostics, wound revision, administration of antibiotics and immobilization were not performed. The following day the patient presented to a hospital with painful swelling and reddening of the left index finger where an emergency surgical wound revision, administration of antibiotics and immobilization of the finger were performed due to a phlegmon of the flexor tendon. Despite subsequent revision operations, necrosis of the flexor tendon sheath occurred with a skin subcutis defect necessitating a full thickness skin transplantation and ultimately operative fusion of the distal interphalangeal joint of the index finger. After a total period of treatment of 9 months the patient still presented with local soft tissue swelling and paresthesia as well as a limited range of motion of the proximal interphalangeal joint. The patient filed a complaint for wrong treatment of the high-pressure injection injury in terms of an inaccurate examination and lack of administration of antibiotics at the first presentation. The expert opinion of the arbitration board ascertained medical malpractice at the first presentation. An emergency surgical wound revision had already been indicated at the first presentation and the revision procedures would have been less extensive and it was highly probability that surgical fusion of the distal interphalangeal joint could have been avoided. The arbitration furthermore concluded that iatrogenic maltreatment led to a phlegmon of the flexor tendon with the need for subsequent revision operations including surgical fusion of the distal interphalangeal joint which resulted in an affected grip control. The delay in surgical treatment must be considered as the reason for the much worse initial situation that finally led to the functional impairment of the left index finger.

Packed red blood cell transfusion is not associated with increased risk of necrotizing enterocolitis in premature infants

OBJECTIVE

Recent reports have posited a temporal association between blood transfusion with packed red blood cells (BT) and necrotizing enterocolitis (NEC). We evaluated the relationship between BT and NEC among infants at three hospitals who were consented at birth into a prospective observational study of NEC.

STUDY DESIGN

We used a case-control design to match each case of NEC in our study population of infants born at<33 weeks postmenstrual age (PMA) to one control infant using hospital of birth, PMA, birth weight and date of birth.

RESULT

The number of transfusions per infant did not differ between 42 NEC cases and their controls (4.0 ± 4.6 vs 5.4 ± 4.1, mean ± s.d., P = 0.063). A matched-pair analysis did not identify an association of transfusion with NEC in either the 48-h or 7-day time periods before the onset of NEC. Stratifying on matched-sets, the Cox proportional hazard model did not identify any difference in the total number of BTs between the two groups (hazard ratio 0.78, 95% confidence interval 0.57 to 1.07, P = 0.11).

CONCLUSION

In contrast to previous studies, our case-control study did not identify a significant temporal association between BT and NEC. Additional large prospective randomized studies are needed to clarify the relationship between BT and NEC.

[Conservative treatment of distal radius fracture. Consequences of an uncritical follow-up]

A 74-year-old woman sustained a fracture of the distal radius with an additional fracture of the styloid process of the ulna due to a fall. After reduction under local anesthesia immobilization treatment in a forearm cast was initiated. Despite increasing secondary dislocation during radiological x-ray follow-up control, the bone was described as correctly aligned by the treating physician and non-operative treatment was continued. After a total treatment period of 9 months including 7 months of physiotherapy the patient still presented a limited range of motion and local soft tissue swelling of the right wrist. The patient filed a complaint for wrong treatment of the distal radius fracture resulting in severe pain and considerable deformity of the right wrist leading to a significant handicap during activities of daily living. The expert opinion of the arbitration board ascertained a case of medical malpractice in terms of the indications. Due to the initial presence of criteria of radiological instability, an operative treatment had already been indicated at the first presentation. In addition, secondary dislocation during radiological follow-up examination should have led to conversion of treatment in favor of surgery. The arbitration board furthermore concluded that iatrogenic malpractice led to a severe deformity of the right wrist which would result in a loss of grip strength and future arthritic deformation of the wrist. Legal aspects of the case are discussed.

[Foreign body retention after soft tissue laceration. A case of insufficient inspection and documentation]

A 52-year-old man sustained a laceration to his left eyebrow after a fall in his bathroom. His plastic glasses shattered upon impact. The patient was referred to a local emergency department. After a quick exploration by the physician on call, the wound was closed by a nurse using the Steri-Strip Wound Closure system. No further exploration or imaging was performed. Four weeks after the incident the patient presented to a dermatologist with a "foreign body sensation" at the site of the laceration. Assuming a foreign body granuloma, he was referred to a maxillofacial surgeon who removed plastic debris (parts of the glasses worn by the patient). The wound subsequently healed without further complications.The patient filed a complaint for inadequate treatment in the emergency department. No detailed patient and accident history had been obtained, the wound exploration performed by the physician was superficial, and the wound closure was performed by a nurse. The expert opinion of the arbitration board ascertained a medical malpractice in terms of insufficient history, examination, and a lack of documentation. Specific questioning of the accident history would have led to the suspicion of possible foreign bodies, thus, leading to a more thorough exploration and likely further imaging. The arbitration board concluded that obtaining a detailed accident history and an accurate examination would have revealed the foreign bodies and/or led to further imaging. Complying with this, the patient could have been spared further harm and secondary surgery would have been unnecessary.

[Incomplete paraplegia after delayed diagnostics of motor function deficits. Severe malpractice?]

A 72-year-old female patient was transferred to a rehabilitation centre after surgical stabilization of a subtrochanteric femoral fracture. However, adequate mobilization was not possible there and 5 days after transfer deficits in the motor function of both lower extremities were documented for the first time and an initial paraplegia was diagnosed the following day by a neurologist. Magnetic resonance imaging (MRI) revealed the suspicion of an unstable fracture of the seventh thoracic vertebral body 8 days after the initial symptoms, which was confirmed by computed tomography after another 3 days. Surgical decompression and stabilization were performed at a department for neurosurgery 4 days later but incomplete paraplegia persisted permanently. The patient complained about insufficient diagnostic measures at the rehabilitation centre. The expert opinion concluded that it would have been mandatory to investigate the matter of the newly occurring neurological symptoms immediately but this had only been performed after undue delay, which had to be interpreted as a case of medical malpractice. The expert pointed out that it was not possible to provide clear evidence that emergent diagnosis and surgery would have enabled a significantly better outcome.The arbitration board ascertained a lack of examination and argued that prompt and adequate diagnostic measures would have revealed the relevant pathological finding and thus surgery would have been performed immediately. According to the reversal of evidence in favor of the patient it could be assumed that no permanent neurological damage existed when the first neurological symptoms occurred and that emergent surgery at least had the potential to prevent permanent paraplegia. This opinion of the arbitration board is supported by numerous references in the literature.

[Curriculum "patient safety" for undergraduate medical students at the department of surgery, University of Greifswald]

BACKGROUND

Risk reducing measures like the surgical checklist have been proven to reduce effectively adverse events and improve patient safety and teamwork among surgical staff members. Nevertheless, many physicians still refuse to use even simple safety tools like the WHO checklist. A progress in patient safety can only be achieved by changing the operating proceedings and mentality of medical students. This is best performed by teaching patient safety already very early in the medical education.

METHOD

The present study demonstrates the implementation and evaluation of the curriculum "patient safety" for undergraduate medical students in the 4th year of medical school at the Department of Surgery, University of Greifswald. 141 students evaluated a total of six lectures from April to October 2011.

RESULTS

The results indicate that young medical students show great enthusiasm in safety matters and are willing to adopt the principles. Especially the importance of the issue and the didactic design were evaluated as being very high.

CONCLUSION

The curriculum "patient safety" as part of the training program in medical school is a powerful and effective educational tool that is able to raise the student's awareness of patient safety affairs. Thereby it is crucial to start early within medical education during the phase of socialisation. We recommend the general implementation of a patient safety curriculum in medical school.

[Malpractice in the treatment of diaphyseal fractures in children - experience of the Arbitration Office of the Northern German Medical Boards]

BACKGROUND

Statistics of the Arbitration Office of the North German Medical Boards for extrajudicial claim resolution show that nearly 30 % of all panel proceedings confirm medical malpractice. In proceedings concerning fractures in children the percentage rises to 63 % with significant differences in various fracture localisations.

METHODS

Between 2000 and 2011 the Arbitration Office dealt with 272 panel proceedings regarding the fracture treatment in children. In this study 83 proceedings concerning the treatment of diaphyseal fractures of the long bones are evaluated.

RESULTS

The claims were related to the following specialities (p = number of proceedings, m = number of malpractices): orthopaedics/traumatology p = 46, m = 38; general surgery p = 17, m = 21; paediatric surgery p = 16, m = 13; anaesthesia p = 1, m = 1; general practitioner p = 2, m = 2. In 7 cases concerning obstetrics (4) and paediatrics (3) no malpractices could be established. In 5 cases two facilities/doctors were included in the same proceeding. On 17 occasions, 2 errors were made that were unrelated to each other. The overall frequency of malpractice was 69 % with no significant differences between the involved facilities. The diaphyseal fracture locations were: humerus p = 5, m = 2; radius and/or ulna (Monteggia fractures excluded): p = 29, m = 20; femur p = 29, m = 20; tibia (with or without fracture of the fibula): p = 20, m = 14. In conservative fracture treatment the following negligent adverse events were confirmed: severe skin lesions owing to either plaster extension or removal of the cast (11), omitted or insufficient reduction followed by consolidation in intolerable malposition (8), no inducement of corrective measures after consolidation in intolerable displacement (11). Following malpractices in the surgical treatment were classified as: no indication for surgical treatment (2), no osteosynthesis in spite of clear indication (3), technical failures in primary osteosynthesis (16), technical failures in repeated osteosynthesis (4), aspiration pneumonia due to missed intubation (1). The applied methods of osteosynthesis were intramedullary nailing, mainly ESIN p = 24, m = 12; plate p = 24, m = 5; fixateur externe p = 7, m = 5. The results of maltreated diaphyseal fractures were altogether moderate: transitional impairment due to delayed or repeated therapeutic measures with prolonged fracture healing, no functional loss 70 %, slight deformation of the forearm, minimal loss of mobility 21 %, remarkable deformation of the forearm with considerable impairment of mobility, especially pronation/supination, deformation of the radio-ulno-carpal joint unit 7 %.

DISCUSSION

There are three main categories in the maltreatment of diaphyseal fractures: 1) Omission of fracture reduction with or without internal stabilisation in cases of relevant axial deviation by unjustified expectation of "spontaneous correction". 2) Omission of fracture reduction in cases of unmotivated or neglected secondary displacement. 3) Technical failures in performing of osteosynthesis resulting in instability or the creation of intolerable malposition requiring re-osteosynthesis. The high number of plate osteosyntheses in our series (44 %) is not representative for the general treatment of children's fractures in Germany. Most cases of plate osteosynthesis are related to corrective measures with clear indication. In nine casuistic representations the errors in treatment are explained.

CONCLUSION

The evaluation of malpractice in the treatment of diaphyseal fractures in children confirms the consensus: correct assessment of fracture type, early adequate treatment and fracture control, early corrective measures after insufficient primary reduction or secondary dislocation, lead to fracture healing without any anatomic or functional deficiency. Reverse argument: fracture healing leading to anatomic and/or functional loss gives a very probable indication of malpractice.

Gut microbiota correlates with energy gain from dietary fibre and appears to be associated with acute and chronic intestinal diseases

Improvements in high-throughput sequencing technologies have spurred a large number of studies aimed at obtaining a better understanding of the composition and the dynamics in gut microbiota and its associations with various human diseases, especially those in the intestinal tract. Here we briefly summarize results from three different such studies from our group, all of which used 454 based high-throughput 16S rRNA sequence analysis combined with other microbiota profiling methods to determine faecal microbiota composition. In the first study, a controlled feeding trial, we establish that energy gain from the consumption of up to 50 g/day of a resistant maltodextrin depends on the prevalent microbiota composition. Over time, resistant maltodextrin supplementation increased the proportion of total faecal bacteria as well as potentially beneficial bifidobacteria. Thus, energy gain from resistant maltodextrin in an individual appears to vary over time and depend on the adaptation of gut microbiota. We then illustrate the power of molecular tools for identifying (i) distortions in early microbiota development in pre-term infants and the presence of potentially novel pathogens contributing to necrotizing enterocolitis and (ii) a specific microbiota signature, based on discriminant analysis of the 16S rRNA sequences, that correlates with the prevalence of an early risk marker associated with colorectal carcinogenesis, intestinal adenoma, in elderly adults.

[Infection after anterior cruciate ligament reconstruction: grave error in treatment?]

A 28-year-old patient showed clear signs of knee joint infection 8 days after arthroscopic reconstruction of the anterior cruciate ligament. The treating physicians recommended further observation although they stated that a knee joint infection could not be reliably excluded. One week later arthroscopic revision was performed and intraoperative smear tests showed infection by Pseudomonas aeruginosa. Therefore, another 6 days later the obviously infected transplant had to be removed. In the long run painful and limited range of motion of the affected knee joint persisted. The patient complained about medical malpractice concerning management of the complication. The expert opinion stated that due to the fateful course of infection the tendon graft could not be retrieved after the eighth day post surgery anyway. Thus, only flawed delay of treatment was criticized. The arbitration board argued, however, that scientific data concerning the fate of infected tendon grafts do not support the expert opinion and that immediate arthroscopy and antibiotic treatment at least had the potential to influence the course of infection in a positive manner. Evidence clearly shows that survival of an infected tendon graft depends on early diagnosis and emergency treatment rather than just on fate. Due to the fact that, although having in mind the possibility of a knee joint infection, the necessary therapy was delayed for 8 days, the arbitration board considered the described medical malpractice a severe treatment error, leading to reversal of evidence in favour of the patient.

[Malpractice in the treatment of fractures and dislocations of the elbow joint in children--experience of the arbitration office of the North German Medical Boards]

BACKGROUND

Statistics of the arbitration office of the North German Medical Boards show that 30% of all panel proceedings confirm medical malpractices. In panel proceedings concerning the treatment of fractures in children, the percentage rose to 60% with significant differences in the individual fracture localisations.

METHODS

Between the years 2000 and 2010, the arbitration office dealt with 257 panel proceedings regarding the fracture treatment of children. This study evaluates the decisions of 53 proceedings concerning the treatment of fractures and dislocations of the elbow joint.

RESULTS

All cases except one concerned the following surgical specialities: 1. orthopaedics/traumatology, n = 14; 2. general surgery, n = 13; 3. paediatric surgery, n = 5. On 7 occasions 2 treatment facilities were involved in the same proceeding. The following types of fractures/dislocations were present (each with the number of proceedings [p] and the confirmed malpractices [m]): fracture of the radial humeral condyle and transcondylar Y-fractures, p = 12, m = 11; fracture of the ulnar epicondyle, p = 2, m = 2; sole dislocation of the radial head as well as in combination with Monteggia lesion, p = 19, m = 17; displaced fracture of the radial head and radial neck, respectively, p = 8, m = 4; fractures of the olecranon, p = 3, m = 2; fracture of the coronoid processus, p = 1, m = 1; dislocations and dislocation fractures of the elbow joint without Monteggia lesion, p = 8, m = 5.

DISCUSSION

42 of these cases (79 %) confirmed malpractice of which 27 (64%) resulted in permanent restriction of the elbow joint mobility. Due to the diversity of injuries, the types of treatment errors were also very variable. In most cases the treatment errors were initiated through the false interpretation of X-ray findings which resulted in false and inadequate therapy measures, for example, the overlooked and not reduced dislocation of the radial head. Three transcondylar Y-fractures were missed on both the X-ray findings and during the operation. In cases where the dislocation of the radial head was not diagnosed in the first instance but operated on within four months (n = 3), a satisfactory result was still achieved. However, if the operation took place at a later time (in our cases 9 months to 8 years after the injury, n = 14) there was no improvement achieved and in many cases the elbow joint mobility deteriorated significantly. In three cases of dislocation of the elbow joint, an intraarticular entrapment of the disjointed ulnar epicondyle was overlooked and therefore not corrected which resulted in deleterious effects on the joint movement. There were five cases with a dislocation combined with a displaced fracture of the radial neck (Mason IV). This fracture was insufficiently reduced/stabilised on two occasions and in one instance the reconstruction of the disrupted joint ligaments was not carried out which resulted in permanent instability of the elbow joint and subluxation. In five casuistic representations the final decision of the arbitration board on the basis of expert reports is illustrated.

CONCLUSION

From a traumatological point of view, the elbow region of a child constitutes a distinct problem zone due to the rarity and diversity of the fractures and dislocations in this area. Relevant experiences in diagnostics and therapy of injuries in this region cannot always be expected. Every doctor who happens to come across a case in which a child suffers from such injuries should be responsible for the timely referral to a treatment facility that has the relevant experience to treat such cases.

[Injury to the median nerve after minimally invasive decompression: discrepancy between the surgical report and actual course of surgery]

A 72-year-old man suffering from carpal tunnel syndrome had undergone minimally invasive decompression by using a SafeGuard® Mini-Open Carpal Tunnel Release System. After the operation the patient presented with a paraesthesia in the median nerve distribution. Two months later an operative revision was performed in another hospital. A partial transection of the median nerve and an incomplete release was seen. The surgeon of the first operation stated that detailed informed consent including the risk of iatrogenic nerve injury had been obtained. Furthermore he referred to the operative report, which mentioned the accuracy of the procedure without any problems or complications during surgery. The Arbitration Board stated that the operative report could not exculpate the surgeon because the findings of the operative revision disagreed with the first operative report. The expert opinion declared that the lesion was a result of an inaccurate operative procedure as the surgeon was not able to demonstrate an anatomical variation of the median nerve.

The developing intestinal microbiome and its relationship to health and disease in the neonate

The intestinal microbiota normally exists in a commensal and/or symbiotic relationship with the host. In the past few years, emerging technologies derived largely from the Human Genome Project have been applied to evaluating the intestinal microbiota and new discoveries using these techniques have prompted new initiatives such as the Human Microbiome Roadmap designed to evaluate the role of the intestinal microbiome in health and disease. In this review, we wish to focus on some new developments in this area and discuss some of the effects of medical manipulations such as antibiotics, probiotics, prebiotics and C-section versus vaginal delivery on the intestinal microbiota.

Metamaterial-based gradient index lens with strong focusing in the THz frequency range

The development of innovative terahertz (THz) imaging systems has recently moved in the focus of scientific efforts due to the ability to screen substances through textiles or plastics. The invention of THz imaging systems with high spatial resolution is of increasing interest for applications in the realms of quality control, spectroscopy in dusty environment and security inspections. To realize compact THz imaging systems with high spatial resolution it is necessary to develop lenses of minimized thickness that still allow one to focus THz radiation to small spot diameters with low optical aberrations. In addition, it would be desirable if the lenses offered adaptive control of their optical properties to optimize the performance of the imaging systems in the context of different applications. Here we present the design, fabrication and the measurement of the optical properties of spectrally broadband metamaterial-based gradient index (GRIN) lenses that allow one to focus THz radiation to a spot diameter of approximately one wavelength. Due to the subwavelength thickness and the high focusing strength the presented GRIN lenses are an important step towards compact THz imaging systems with high spatial resolution. Furthermore, the results open the path to a new class of adaptive THz optics by extension of the concept to tunable metamaterials.

Monitoring technologies in the neonatal intensive care unit: implications for the detection of necrotizing enterocolitis

Necrotizing enterocolitis is the most common and fulminant gastrointestinal disease affecting neonates. Its pathogenesis is heterogeneous and not clearly understood. Early detection could prevent some of the devastating consequences of this disease, but currently there is no noninvasive method of reliable early-stage detection. Here, we review various noninvasive monitoring technologies that have already been employed or show promise for early detection. Each method may have an important role after its technical difficulties are resolved. These are discussed in detail as they relate to various aspects of the putative pathophysiology of this devastating disease.

[Manipulative treatment of the cervical spine and stroke]

Manipulative therapy of the cervical spine is associated with a considerable risk of stroke. We evaluated all cases with the diagnosis of arterial dissection submitted between 1996 and 2005 to the Schlichtungsstelle für Arzthaftpflichtfragen der Norddeutschen Arztekammern for assessment of the accusations brought against the therapists who conducted the manipulation. Neither in the 7 carotid nor in the 9 vertebral artery cases could a causal link be made between the dissection and the manipulation. However, in 5 of the 7 carotid and 7 of the 9 vertebral artery dissections there was clear evidence or high probability that the dissection was present prior to the manipulation, and had caused neck pain, segmental dysfunction and, in some cases, even neurological symptoms. Stroke after manipulative therapy was due to embolisation of thrombotic material from the dissected artery. As both cervical arterial dissection and cervical spine disorder usually cause similar signs and symptoms physicians must differentiate between these two entities prior to any manipulative therapy. Clinical indicators of pre-existent dissection and the medicolegal implications are discussed in this paper.

[Malpractice in the diagnosis and treatment of the slipped capital femoral epiphysis]

INTRODUCTION

Expert commissions (Gutachterkommissionen) and arbitration offices (Schlichtungsstellen) in Germany are expert panels for the extrajudical resolution of malpractice claims. The performance of arbitration panel proceedings ("Schlichtungsverfahren") is based on the German medical and insurance jurisdiction.

METHOD

39 arbitration panel proceedings concerning supposed malpractice in the diagnosis and treatment of slipped capital femoral epiphysis were evaluated in regard to the involved clinics and physicians and, respectively, the medical specialties, type of slippage (acute or chronic), malpractice and the disabilities caused by malpractice.

RESULTS

In 28 cases (72 %) the malpractice was confirmed, the average of confirmed failures in all proceedings being about 30 %. The failures could be classified as misdiagnosis followed by inadequate treatment and failures in operative treatment. Minor and moderate permanent disabilities due to malpractice remained in 8 cases, severe permanent disability resulted in 14 cases due to osteonecrosis of the femoral head.

DISCUSSION

The results are discussed with regard to the avoidance of mistakes in diagnosis and treatment and the problems of medical assessment.

[Injuries in anaesthesia. Results of the Hannover arbitration procedure 2001-2005]

The Schlichtungsstelle in Hannover (expert panel for arbitration), northern Germany, was founded in 1976 to settle disputes between patients and doctors. Furthermore, publications regarding the decisions of the Schlichtungsstelle serve as an important medium to prevent malpractice by increasing doctors' awareness of critical processes in their field. Between 2001 and 2005 the Schlichtungsstelle decided on 435 malpractice claims in anaesthesia. An accumulation of injuries was observed in anaesthetic procedures with respect to the airways (23.9%), injuries related to regional anaesthesia (18.2%), vasopuncture (13.1%) and positioning of the patients (9.9%). In 21.8%, the Schlichtungsstelle advised to seek a resolution without going to court by paying financial compensation in favour of the patient. In these cases the Schlichtungsstelle's evaluation had come to the conclusion that malpractice was the cause of the patient's injury. We would like to mention that 21 cases of intraoperative awareness were included in the claims, of which 52.4% (average 21.8%) were evaluated to be the result of malpractice and thus financial compensation was advised. The appropriate care for the patient, required from every doctor, calls the anaesthesiologists to avoid all possible malpractices, thus reducing patients' injury due to such malpractices to a minimum. But even injuries not caused by malpractice need to be examined closely and improvement should be sought.

[Evaluation of 157 arbitration procedures against maxillofacial surgeons handled by the arbitration office of the North German Medical Associations from 2000 to 2005]

Medical work is, just like any other profession, not always without error and even when no mistake has been made the patient may suffer health damages, because such are the unavoidable risks. Arbitration procedures of medical liability disputes can in particular cases resolve the individual conflict between physician and patient. The results of these arbitration procedures can point towards the main focus of diagnosis, patient accusations (patient dissatisfaction) and treatment errors. In the space of 6 years from 2000 until 2005 the North-German arbitration office handled 157 arbitration procedures against Maxillofacial surgeons. The decisions were statistically and casuistically analysed with regard to patient accusations, type of treatment error, frequency of treatment error, health damages that were caused and not caused by errors. Liability claims against a physician result only from those errors that have caused health damages to a patient. Not all errors cause damage automatically. Patient claims were found to be justified in 28% of all procedures and a recommendation for regulation was made to the physician's insurance. Maxillofacial surgery, with reference to the 20.4% of cases analysed, clearly represents less than the total average. The main focus of accusations raised by patients and also the main focus of the observed treatment errors are operative errors as a cause of sensitivity defects of the lower lip and the tongue, also of tongue damages and their associated taste defects. Parallel to the 20.4% of cases, which showed iatrogenic health damages caused by errors, 60.9% of cases showed patients had also suffered iatrogenic damages even though no medical errors had caused them.

NICHD: AAP workshop on neonatology research and training areas of research in neonatal gastroenterology

Future research in neonatal and developmental gastroenterology should include inquiry well beyond finding a cure or better preventative measures against necrotizing enterocolitis. The gastrointestinal (GI) tract acts not only as a digestive-absorptive organ; it also serves major endocrine and neural functions. It encompasses a vast surface area exposed to the external environment and plays a major role in both innate and adaptive immunity. Numerous short- and long-term health benefits could be derived from a better understanding of the developing GI tract.

Tight junctions, leaky intestines, and pediatric diseases

BACKGROUND

Tight junctions (TJs) represent the major barrier within the paracellular pathway between intestinal epithelial cells. Disruption of TJs leads to intestinal hyperpermeability (the so-called "leaky gut") and is implicated in the pathogenesis of several acute and chronic pediatric disease entities that are likely to have their origin during infancy.

AIM

This review provides an overview of evidence for the role of TJ breakdown in diseases such as systemic inflammatory response syndrome (SIRS), inflammatory bowel disease, type 1 diabetes, allergies, asthma, and autism.

CONCLUSION

A better basic understanding of this structure might lead to prevention or treatment of these diseases using nutritional or other means.

The role of intraoperative digital subtraction angiography for quality control of standard carotid endarterectomy using patch angioplasty

The absence of technical defects is considered to be of great importance during carotid endarterectomy (CEA). In this context, both safe surgical technique and intraoperative quality control may be a fundamental part of the operative procedure. We have therefore undertaken a prospective study to evaluate the possible benefits of completion angiography in standard CEA using patch angioplasty. The objectives were three-fold: (1) to identify the incidence of defects requiring prompt revision; (2) to assess the perioperative stroke rate as well as the number of residual stenosis after 6 weeks in angiographically controlled patients and (3) to compare these results with a control group. From 1 January to 30 September 1999 111 patients with 115 consecutive CEAs which had completion angiography (Group A) were prospectively entered into this study. The results in group A were compared with a series of again 111 patients (Group B) which had 116 CEAs without intraoperative quality control between January and September in the year before. Surgical technique was identical in both groups. In general, risk factors were distributed evenly among both group with the exception that in group A were significantly more high-grade ipsilateral ICA stenoses while group B had more patients with diabetes and ipsilateral CT-defects. In group A, angiographic irregularities prompted us to immediate re-exploration in five patients (dilatation of severe ICA spasm 1; re-exploration of distal ICA occlusion 1; reopening of occluded ECA 3). With a 30 day mortality of 0% each perioperative stroke rate was comparable with 3/115 in group A and 3/116 in group B (P=1.0). 2/3 patients with neurological deficits in group A had early postoperative carotid thrombosis--in spite of a normal completion study. Duplex examination after 6 weeks revealed one asymptomatic ICA occlusion in each group. The incidence of residual stenosis (> or =50%) was not significantly different being 3.7% in group A and 3.2% in group B (P=0.85). When applying a safe and simple operative technique for CEA, the incidence of abnormalities warranting immediate correction appears to be a rare event and, therefore, the necessity for obligatory quality control may be questionable. On the other hand, completion DSA allows a simple documentation of the adequacy of the surgical procedure.

Glutamine in the fetus and critically ill low birth weight neonate: metabolism and mechanism of action

Of all the amino acids, glutamine is the most versatile. Studies in the maternal-fetal-placental unit demonstrate that both glutamine and glutamate play an important role in fetal and placental metabolism. If an infant is born very prematurely, the supply of glutamine from the mother is suddenly interrupted. The infant is dependent on endogenous synthesis or an exogenous supply of glutamine to meet the challenges of the external environment and a tripling of body weight in the first 3-4 mo of life. Studies of glutamine supplementation in low birth weight infants and critically ill adults suggest benefits, especially in terms of decreased nosocomial infections. Two large multicenter trials are currently underway that are designed to address these potential benefits in very low birth weight infants. These trials will not explain the mechanism of action. This review raises hypotheses about the role of the amide nitrogen of glutamine for nucleotide and glucosamine synthesis in the small intestine and how this might relate to greater integrity of the intestinal mucosa, hence preventing bacterial translocation and/or the subsequent proinflammatory response that might lead to multiorgan failure.

Effect of protein shape on multibody interactions between membrane inclusions

The elastic interaction of membrane inclusions provides one of the simplest physical realizations of multibody forces. Here we show how the cross-sectional shape of the inclusion greatly changes the character of the interaction, and illustrates a pattern formation mechanism. The formalism provides a transparent framework for modeling bilayer-inclusion boundary effects on the multibody interaction.

Glutamine supplementation in low-birth-weight infants: mechanisms of action

Very low-birth-weight infants have minimal endogenous nutritional reserves and are at high risk for stresses that induce further breakdown of these diminished reserves. They frequently receive very little glutamine because enteral feedings are often delayed and glutamine is not included in parenteral nutrition. Here we describe studies of glutamine supplementation in very low-birth-weight infants and discuss potential mechanisms for the beneficial effects.

Necrotizing enterocolitis: pathophysiology and prevention

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in the neonatal intensive care unit. It is a disease of medical progress in that more very low-birth-weight neonates are surviving than ever before and are thus susceptible to this potentially devastating disease. NEC received very little attention in the literature before the 1970s but now is well known to all neonatologists and pediatric surgeons. The 1500 to 2000 infants that die every year from this disease in the United States and the large number of infants who develop short gut syndrome from this disease only represent the tip of the iceberg of the problems NEC causes. The widespread fear of NEC among neonatologists and pediatric surgeons has contributed in large part to the use of the IV route rather than the gastrointestinal tract for nourishing these infants for relatively long periods. The consequences of this include a high incidence of sepsis, high hospital costs, and potential long-term neurodevelopmental disability because of poor nutrition during a very vulnerable period of growth and development. The purpose of this review is to provide a brief overview of the clinical presentation and current treatment for NEC, then provide a discussion of the pathophysiology on which strategies for prevention can be formulated.

Glutamine synthetase: a key enzyme for intestinal epithelial differentiation?

BACKGROUND

We have previously shown that glutamine synthetase protein and mRNA are concentrated in the crypt region of the rat small intestine and that the activity of this enzyme is highest around the time of weaning. This anatomical location and time of peak activity are sites and periods of active enterocyte differentiation. This led to our current hypothesis that glutamine synthetase is important in the differentiation of enterocytes.

METHODS

To test our hypothesis, we treated Caco-2 cells with physiologic (0.6 mM) glutamine concentrations in cell culture medium. The experimental group was treated with methionine sulfoximine, an irreversible glutamine synthetase inhibitor, and the control group with phosphate buffered saline. Three standard and well-defined markers of intestinal differentiation-sucrase-isomaltase activity, microvillus formation, and electrical impedance in transwell plates-were compared between the two groups.

RESULTS

The methionine-sulfoximine-inhibited group was found to have lower sucrase-isomaltase activity, a lower density of microvilli, and lower electrical impedance values over time compared with the control group.

CONCLUSION

The experimental group was found to be less differentiated by all three markers of differentiation. Therefore, glutamine synthetase is important for Caco-2 cell differentiation.