Evidence for the formation of two types of oxygen interstitials in neutron-irradiated α-Al2O3 single crystals

Due to unique optical/mechanical properties and significant resistance to harsh radiation environments, corundum (α-Al2O3) is considered as a promising candidate material for windows and diagnostics in forthcoming fusion reactors. However, its properties are affected by radiation-induced (predominantly, by fast neutrons) structural defects. In this paper, we analyze thermal stability and recombination kinetics of primary Frenkel defects in anion sublattice − the F-type electronic centers and complementary oxygen interstitials in fast-neutron-irradiated corundum single crystals. Combining precisely measured thermal annealing kinetics for four types of primary radiation defects (neutral and charged Frenkel pairs) and the advanced model of chemical reactions, we have demonstrated for the first time a co-existence of the two types of interstitial defects – neutral O atoms and negatively charged O- ions (with attributed optical absorption bands peaked at energies of 6.5 eV and 5.6 eV, respectively). From detailed analysis of interrelated kinetics of four oxygen-related defects, we extracted their diffusion parameters (interstitials serve as mobile recombination partners) required for the future prediction of secondary defect-induced reactions and, eventually, material radiation tolerance.

Closure of large lumbosacral defect using a combined method of bilateral bipedicle flap with lateral releasing incision and Integra® dermal regeneration template

BACKGROUND: Myelomeningocele is one of the most complex congenital malformations of the central nervous system. It is one of the most common types of spina bifida which involves a failure of neural tube closure. Reconstruction surgery for myelomeningocele had always been challenging for plastic and neurosurgeons. CLINICAL CASE: We report a case of a new-born with lumbosacral myelomeningocele who received treatment in the Hospital Universiti Sains Malaysia. The myelomeningocele was repaired by the neurosurgery team and subsequently, the child was left with huge lumbosacral skin defect. The large defect was successfully covered by using a combined method of bilateral bipedicle flap with lateral releasing incision and remaining lumbosacral and secondary defect resurfaced using Integra dermal regeneration template (DRT). We used ACTICOAT interfaced negative pressure wound therapy (NPWT) as our main dressing in preparing the wound bed for autologous epidermal graft. The result of our closure technique provides tension free closure. DISCUSSION: We incorporated bilateral bipedicle fasciocutaneous flap technique together with DRT for closure of the lumbosacral defect. The bilateral bipedicle flap with lateral releasing incision served to reduce tension on the skin at bilateral lumbar region. The DRT downsized the lumbosacral defect and NPWT dressing provided an optimal sterile environment in giving time for neodermis generation. The remaining secondary defect were also resurfaced utilizing DRT and autologous skin grafting. CONCLUSIONS: The outcome of surgery demonstrated that the combined use of bilateral bipedicle fasciocutaneous flap with lateral releasing incision and DRT with delayed skin grafting is safe, effective and provide long term stable and supple scar for large, exposed dura defect.

554 An Unusual Case of a “Hernia Within a Hernia” Resulting in Small Bowel Obstruction and Strangulation

59-year-old female presented with symptoms of small bowel obstruction. She had a history of previous open right hemi-colectomy. She also had a previous complex strangulated ventral hernia which had required laparotomy and repair. Following this the patient had recurrence of the ventral hernia. Examination demonstrated a non-tender irreducible recurrent ventral hernia in a patient with a high BMI (> 40). CT reported a midline hernia containing dilated small bowel loops. Additionally, there was a separate narrower hernia arising from the original larger hernia containing a strangulated loop of small bowel. Emergency laparotomy was performed. At operation there was a large hernia containing a smaller secondary hernial defect. Within this secondary defect, there was a loop of jejunum with a constriction band. which was released. There was no vascular compromise to the bowel and no need for resection. The hernial sac was excised and the abdominal wall repaired. Post-operative recovery was uneventful. Discussion The patient had a known, recurrent wide necked ventral hernia. However, this was the first presentation of the new, smaller hernia. This case is unusual in that it demonstrates a multi-locular “hernia within a hernia”. Although multi-locular hernias have been previously described, there is a paucity of literature on these. Conclusions This “hernia within a hernia” is an uncommon surgical finding for which there is limited literature. Clearly without urgent surgical intervention there would be an increase in morbidity and mortality.

Quantitative Assessment of Ciliary Ultrastructure with the Use of Automatic Analysis: PCD Quant

The ciliary ultrastructure can be damaged in various situations. Such changes include primary defects found in primary ciliary dyskinesia (PCD) and secondary defects developing in secondary ciliary dyskinesia (SCD). PCD is a genetic disease resulting from impaired ciliary motility causing chronic disease of the respiratory tract. SCD is an acquired condition that can be caused, for example, by respiratory infection or exposure to tobacco smoke. The diagnosis of these diseases is a complex process with many diagnostic methods, including the evaluation of ciliary ultrastructure using transmission electron microscopy (the golden standard of examination). Our goal was to create a program capable of automatic quantitative analysis of the ciliary ultrastructure, determining the ratio of primary and secondary defects, as well as analysis of the mutual orientation of cilia in the ciliary border. PCD Quant, a program developed for the automatic quantitative analysis of cilia, cannot yet be used as a stand-alone method for evaluation and provides limited assistance in classifying primary and secondary defect classes and evaluating central pair angle deviations. Nevertheless, we see great potential for the future in automatic analysis of the ciliary ultrastructure.

Paroxysmal Dyskinesias Revealing 3-Hydroxy-Isobutyryl-CoA Hydrolase (HIBCH) Deficiency

Paroxysmal dyskinesias (PD) are rare movement disorders characterized by recurrent attacks of dystonia, chorea, athetosis, or their combination, with large phenotypic and genetic heterogeneity. 3-Hydroxy-isobutyryl-CoA hydrolase (HIBCH) deficiency is a neurodegenerative disease characterized in most patients by a continuous decline in psychomotor abilities or a secondary regression triggered by febrile infections and metabolic crises.We describe two PD patients from two pedigrees, both carrying a homozygous c.913A > G, p.Thr305Ala mutation in the HIBCH gene, associated with an unusual clinical presentation. The first patient presented in the second year of life with right paroxysmal hemidystonia lasting for 30 minutes, without any loss of consciousness and without any triggering factor. The second patient has presented since the age of 3 recurrent exercise-induced PD episodes which have been described as abnormal equinovarus, contractures of the lower limbs, lasting for 1 to 4 hours, associated with choreic movements of the hands. Their neurological examination and metabolic screening were normal, while brain magnetic resonance imaging showed abnormal signal of the pallidi.We suggest that HIBCH deficiency, through the accumulation of metabolic intermediates of the valine catabolic pathway, leads to a secondary defect in respiratory chain activity and pyruvate dehydrogenase (PDH) activity and to a broad phenotypic spectrum ranging from Leigh syndrome to milder phenotypes. The two patients presented herein expand the spectrum of the disease to include unusual paroxysmal phenotypes and HIBCH deficiency should be considered in the diagnostic strategy of PD to enable adequate preventive treatment.

Reconstruction of a secondary scalp defect using the crane principle and a split-thickness skin graft

Background Scalp reconstruction is a common challenge for surgeons, and there are many different treatment choices. The “crane principle” is a technique that temporarily transfers a scalp flap to the defect to deposit subcutaneous tissue. The flap is then returned to its original location, leaving behind a layer of soft tissue that is used to nourish a skin graft. Decades ago, it was commonly used for forehead scalp defects, but this useful technique has been seldom reported on in recent years due to the improvement of microsurgical techniques. Previous reports mainly used the crane principle for the primary defects, and here we present a case with its coincidental application to deal with a complication of a secondary defect. Case report We present a case of a 75-year-old female patient with a temporoparietal scalp squamous cell carcinoma (SCC). After tumor excision, the primary defect was reconstructed using a transposition flap and the donor site was covered by a split-thickness skin graft (STSG). Postoperatively, the occipital skin graft was partially lost resulting in skull bone exposure. For this secondary defect, we applied the crane principle to the previously rotated flap as a salvage procedure and skin grafting to the original tumor location covered by a viable galea fascia in 1.5 months. Both the flap and skin graft healed uneventfully. Conclusions Currently, the crane principle is a little-used technique because of the familiarity of microsurgery. Nevertheless, the concept is still useful in selected cases, especially for the management of previous flap complications.

COMBINED USE OF TURNOVER AND PIVOT FLAP FOR DOUBLE LAYER CLOSURE OF POSTAURICULAR FISTULA

ABSTRACT Repair of post auricular stula are challenging owing to scarred tissue and poor blood supply in this area. Various techniques including locoregional ap cover and cavity obliteration have been utilized to repair this complicated problem. In our report, we introduce a novel technique using a double layer closure utilising local skin ap successful lasting results. Two young adults of age 18 Male and 21 year female. Size of stulas were ranging from 1x2 and 2x2 cm respectively in size. Once the stulous tract was excised two aps were planned for double layer closure of stula. First ap for inner lining was turnover ap. Then another local pivot ap is planned to cover the secondary defect or the raw area. It can be either simple rotation ap as in rst case or Limberg type local transposition nd defect (2 case) ap. Both stulas were healed well. KEYWORDS : Fistula , Post auricular, Flap Closure

New therapies for von Willebrand disease

The management of von Willebrand disease (VWD) is based upon the dual correction of the primary hemostasis defect, due to the inherited deficiency of von Willebrand factor (VWF), and of the secondary defect of factor VIII coagulant activity (FVIII:C), due to the loss of binding and stabilization by VWF of this intrinsic coagulation factor in flowing blood. The traditional therapeutic weapons (the synthetic derivative of the antidiuretic hormone desmopressin and plasma-derived VWF/FVIII concentrates) are able to transiently correct both the defects. With the goal of tackling the primary deficiency in the disease, that is, VWF, but at the same time exploiting the normal capacity of patients to produce FVIII, the novel approach of replacing only VWF was implemented in the last 10 years. Following the manufacturing of a concentrate fractionated from human plasma and of one obtained by recombinant DNA technology, clinical studies have shown that VWF-only products correct not only the primary VWF deficiency but also the secondary FVIII:C deficiency. The demonstrated efficacy of these products in various clinical situations and, ultimately, in such a hemostasis-challenging context as surgery testifies to the effectiveness and safety of this approach. It remains to be seen whether VWF-only products are efficacious and safe in still-unexplored situations, such as use in children; the long-term use for prophylaxis; and in recurrent gastrointestinal (GI) bleeding due to angiodysplasia, a major therapeutic problem in VWD.

New therapies for von Willebrand disease

The management of von Willebrand disease (VWD) is based upon the dual correction of the primary hemostasis defect, due to the inherited deficiency of von Willebrand factor (VWF), and of the secondary defect of factor VIII coagulant activity (FVIII:C), due to the loss of binding and stabilization by VWF of this intrinsic coagulation factor in flowing blood. The traditional therapeutic weapons (the synthetic derivative of the antidiuretic hormone desmopressin and plasma-derived VWF/FVIII concentrates) are able to transiently correct both the defects. With the goal of tackling the primary deficiency in the disease, that is, VWF, but at the same time exploiting the normal capacity of patients to produce FVIII, the novel approach of replacing only VWF was implemented in the last 10 years. Following the manufacturing of a concentrate fractionated from human plasma and of one obtained by recombinant DNA technology, clinical studies have shown that VWF-only products correct not only the primary VWF deficiency but also the secondary FVIII:C deficiency. The demonstrated efficacy of these products in various clinical situations and, ultimately, in such a hemostasis-challenging context as surgery testifies to the effectiveness and safety of this approach. It remains to be seen whether VWF-only products are efficacious and safe in still-unexplored situations, such as use in children; the long-term use for prophylaxis; and in recurrent gastrointestinal (GI) bleeding due to angiodysplasia, a major therapeutic problem in VWD.