[Seat-belt syndrome in a pre-school child]

The authors report on a pre-school child with a typical presentation of the trauma caused by a car safety belt and termed the seat-belt syndrome. The deceleration mechanism which throws the upper body forward in the presence of a rigid belt over the abdominal region results in large contusions of the abdominal wall and trauma to the spine, retroperitoneum, and intra-abdominal organs, or even the chest. In making the diagnosis a thorough examination of the spine is necessary as well as a repeated surgical examination of the abdomen, because seat-belt syndrome is often associated with small intestine rupture, a symptom which can remain unrecognised at the early stage. In the case of a four-year-old boy described here, two loops of the small intestine were resected for perforation; stabilization of the vertebral column was indicated on the 5th post-injury day because of decompensated diabetes and deteriorated health state following intra-abdominal surgery. In this boy, poor compensation of juvenile diabetes resulted in infectious complications requiring repeated drainage of an abscess of the abdominal wall injured by the seat belt.The abdominal wall healed within 2 months, diabetes was managed with insulin therapy and good spondylodesis was achieved at 9 months after the injury.

Mitochondrial DNA content and expression of genes involved in mtDNA transcription, regulation and maintenance during human fetal development

The mitochondrial biogenesis and adequate energy production are important for fetal growth and early postnatal adaptation. The aim of the study was to characterize mitochondrial DNA (mtDNA) content and expression patterns of POLG, TFAM, NRF1,NRF2 and PGC1 family of regulated coactivators (PGC1A, PGC1B and PRC) involved in the mtDNA transcription, regulation and maintenance in human fetal tissues during second trimester of gestation. Further the mRNA expression profiles of selected cytochrome c oxidase (COX) subunits were analysed. Moreover enzyme activities of COX and CS and protein levels of COX subunits were analysed. DNA, RNA and proteins were isolated from 26 pairs of fetal liver and muscle samples obtained at autopsy after termination of pregnancy for genetic indications unrelated to OXPHOS deficiency between 13th and 28th week of gestation. This work offers a broad view on the mtDNA content changes in two different tissues during the second trimester of gestation and in the corresponding tissues after birth. The important differences in expression of POLG, TFAM, NRF2 genes and family PGC1 coactivators were found between the fetal tissues. The significant tissue-specific changes in expression of selected COX subunits on mRNA level (COX4 and MTCO2) were observed. Further the considerable differences in enzyme activities of COX and CS are demonstrated between fetal and postnatal phase. In conclusion our study indicates that the fetal developing tissues might differ in the control of mitochondrial biogenesis depending on their energy demand and the age of gestation. Moreover the gene expression is changed mainly on transcriptional level through fetal period.

[Suicidal jumper's fracture]

PURPOSE OF THE STUDY

The characteristics, diagnosis, classification and treatment options of rare fractures of the sacrum known as suicidal jumper's fractures are presented based on six illustrative cases.

MATERIAL AND METHODS

Jumper's fractures of the sacrum are characterised by an H- or U-shaped fracture line in the upper sacrum, usually involving the S1-S2 region. Typically, the anterior segment of the pelvic ring is not injured. In most cases this injury is associated with polytrauma and it is imperative that the patients undergo thorough neurological examination including that for perineal sensitivity and anal tone.

RESULTS

Between 1998 and 2007, 109 patients were treated for AO/OTA type C pelvic injuries at the Department of Orthopaedics and Traumatology. A bilateral fracture of the sacrum with a typical fracture line, i.e., suicidal jumper's fracture, was recorded in six patients (5.5 %), which accounts for 1.2 % of the total number of the pelvic fractures treated. Five patients underwent surgery, one was treated conservatively. Neurological deficit was recorded in five of the six patients. Surgery resulted in bone union and overall improvement in five patients, the patient treated conservatively showed lasting neurological deficit with no progression; she developed pseudoarthrosis.

DISCUSSION

Transverse fracture of the sacrum, in the literature referred to as suicidal jumper's fracture, is a rare injury. In 1985 Roy-Camille introduced a classification system for sacral fractures. In the classification proposed by Denis et al., transalar, transforaminal and central fractures are distinguished, with transverse fractures being included. For making exact diagnosis, the AO/OTA classification is necessary. There is a wide range of neurological features associated with displaced sacral fractures. It includes motor and sensory deficit in L5 and S1 dermatomes and myotomes, dysfunction of the sphincters, perineal insensitivity and possibly also sexual dysfunction. Based on the Denis classification, zone I fractures are responsible for 5.9 %, zone II fractures for 28.4 % and zone III fractures for 56.7 % of the neurological deficits associated with sacral injuries. In patients with zone III fractures, urinary bladder innervation and sexual dysfunction are recorded in 76 %, and neurological deficit in 41 %, of which two-thirds are motor neuron lesions. Motor deficits are most often due to L5 and S1 root lesions; sensory deficits result from S2-S5 and L5 root lesions. External rotation and vertical displacement produce a traction mechanism, comminution and impaction of the massa lateralis result in nerve compression. Sacral fractures can be treated conservatively or surgically. Conservative therapy, bed rest, traction and gradual physical therapy are indicated in children and adolescents with non-displaced or slightly displaced sacral fractures, either without or with minimal neurological symptoms. Surgical treatment involving nerve decompression, open reduction of the fracture and subsequent fixation of the fragments is indicated in all displaced fractures. When nerve structures are affected, the injury-surgery interval should not exceed six hour.

CONCLUSIONS

Sacral fractures known as suicidal jumper's fractures are rare but very serious injuries difficult to diagnose. All injured patients should undergo a thorough neurological examination, including perineal sensitivity and anal tone. The treatment includes nerve decompression, fragment reduction and the restoration of sacral and pelvic stability necessary for neurological recovery, early rehabilitation and good clinical outcome.

SURF1 missense mutations promote a mild Leigh phenotype

SURF1 gene mutations are the most common cause of Leigh syndrome (LS), a rare progressive neurodegenerative disorder of infancy, characterized by symmetric necrotizing lesions and hypervascularity in the brainstem and basal ganglia, leading to death before the age of 4 years. Most of the reported mutations create premature termination codons, whereas missense mutations are rare. The aim of the study was to characterize the natural history of LS patients carrying at least one missense mutation in the SURF1 gene. Nineteen such patients (8 own cases and 11 reported in the literature) were compared with a reference group of 20 own c.845_846delCT homozygous patients, and with other LS(SURF-) cases described in the literature. Disease onset in the studied group was delayed. Acute failure to thrive and hyperventilation episodes were rare, respiratory failure did not appear before the age of 4 years. Dystonia, motor regression and eye movement dissociation developed slowly. The number of patients who survived 7 years of life totaled 9 out of 15 (60%) in the 'missense group' and 1 out of 26 (4%) patients with mutations leading to truncated proteins.

IN CONCLUSION

(i) The presence of a missense mutation in the SURF1 gene may correlate with a milder course and longer survival of Leigh patients, (ii) normal magnetic resonance imaging (MRI) findings, normal blood lactate value, and only mild decrease of cytochrome c oxidase (COX) activity are not sufficient reasons to forego SURF1 mutation analysis in differential diagnosis.

A new case of ALG8 deficiency (CDG Ih)

Congenital disorders of glycosylation (CDG) represent an expanding group of inherited diseases. One of them, ALG8 deficiency (CDG Ih), leads to protein N-glycosylation defects caused by malfunction of glucosyltransferase 2 (Dol-P-Glc:Glc1-Man(9)-GlcNAc(2)-P-P-Dol glucosyltransferase) resulting in inefficient addition of the second glucose residue onto lipid-linked oligosaccharides. So far, only five patients have been described with ALG8 deficiency. We present a new patient with neonatal onset. The girl was born at the 29th week of gestation complicated by oligohydramnios. Although the early postnatal adaptation was uneventful (Apgar score 8 and 9 at 5 and 10 min), generalized oedema, multifocal myoclonic seizures, and bleeding due to combined coagulopathy were present from the first day. Diarrhoea progressing to protein-losing enteropathy with ascites and pericardial effusion developed in the third week of life. Pharmacoresistant seizures and cortical, cerebellar and optic nerve atrophy indicated neurological involvement. No symptoms of liver disease except coagulopathy were observed; however, steatofibrosis with cholestasis was found at autopsy. The girl died at the age of 2 months owing to the progressive general oedema, bleeding and cardio-respiratory insufficiency. Molecular analysis revealed two heterozygous mutations in the ALG8 gene: c.139A>C (p.T47P) and the novel mutation c.1090C>T (p.R364X).

CONCLUSION

The prognosis of patients with ALG8 deficiency is unfavourable. The majority of affected children have early onset of the disease with heterogeneous symptoms including multiple organ dysfunction, coagulopathy and protein-losing enteropathy. Neurological impairment is not a general clinical symptom, but it has to be taken into consideration when thinking about ALG8 deficiency.

[Mid-term results of 360-degree lumbar spondylodesis with the use of a tantalum implant for disc replacement]

PURPOSE OF THE STUDY

The study presents the mid-term results in patients treated with circumferential, i.e., 360-degreee, fusion of the lumbar spine carried out by posterolateral instrumented spondylodesis and anterior intersomatic fusion using a tantalum implant for replacement of an intervertebral disc. The aim of the study was to verify tantalum implant quality, to evaluate segment fusion and to assess the outcome of this method by patients' subjective findings.

MATERIAL AND METHODS

The prospective non-randomised study included the implantation of 47 tantalum cages in 40 patients by the technique of anterior lumbar interbody fusion (ALIF) and posterolateral spondylodesis. Only patients followed up longer than for one year were included in this evaluation. The patient group comprised 16 men and 24 women, with an average age of 47.9 years. The patients indicated for this procedure had mono- or bisegmental lumbar disc degeneration with advanced chan- ges of articular facets. The procedure involved posterior transpedicular screw fixation with decompression, if spinal stenosis existed, and reposition of the segment, if spondylolisthesis was present, and posterior spondylodesis by the open book method. No autogenous bone grafts were used because of the risk of donor-site pain and because one of the aims of the study was to test tantalum cage properties. Subsequently, ALIF and disc replacement with a tantalum cage were carried out after cage insertion, the anterior borders of the upper and lower adjacent vertebral bodies were adjusted so that the lamellar bone should overlap the cage and thus provide continual bridging for the segment, with an emphasis being on joining the lamellae with preserving their blood supply from the respective vertebral bodies. RESULTS Implant subsidence in a rotation/flexion fashion, i.e. ventrally into the upper endplate of the distal vertebra and dorsally into the lower endplate of the proximal vertebra, was observed in two cases; subsidence in a vertical fashion, i.e., symmetrically into the lower endplate of the upper vertebra was found in one patient. Neither vertical mode of subsidence into the upper endplate of the lower vertebra only, nor rotation/extension type of subsidence was recorded.No frontal/rotational mode of subsidence was found either. No osteolytic lesion between the implant and adjacent bone was diagnosed. No migration of an implant sideways or in a ventral/dorsal direction was detected. Anterior bridging fusion was observed in 32 cages. No fusion dorsal to or lateral to the cage was seen. Evaluation of bone ingrowth into the cage was not possible due to a high X-ray contrast effect of the material. High-quality bridging posterolateral spondylodesis was diagnosed in 33 cases. Subjective evaluation by the patients was based on a visual analogue scale (VAS) and an Oswestry Disability Index (ODI) questionnaire. For the whole group, the average VAS value for back pain dropped from 58.3 points before surgery to 18.1 points at one year post-operatively; there were no differences between the genders. The VAS value for leg pain decreased from 54.1 pre-operatively to 9.4 at one year after surgery. Also, the results of ODI assessment were similar in both genders, with the average value for the whole group having decreased from 53.5 % pre-operatively to 29.0 % at one year post-operatively.

DISCUSSION

By using the mechanical properties of a tantalum implant, i.e., its high strength and flexibility, the structure almost identical to cancellous bone and its high stability following implantation, we avoided the necessity of harvesting autogenous bone grafts from the iliac crest. Instead, we introduced the method of bridging a stable and strong implant with lamellar bone, while preserving its blood supply from the adjacent vertebral bodies. Our results showed that this approach resulted in implant subsidence in 1.8 % of cases only.We achieved good-quality fusion by bridging the whole segment in 68 %, and diagnosed good posterolateral fusion in 71 % of the cases. All patients showed good spondylodesis, which was either ante- rior, posterior or bilateral.

CONCLUSIONS

Avery stable fixation of the lumbar spinal segment can be achieved by using posterolateral fusion and ALIF.With this approach, ALIF is augmented with a porous tantalum cage, and the use of autogenous bone grafts, derived from the adjacent anterior vertebral borders and placed before the cage, results in high-quality anterior bridging spondylodesis in a lar- ge proportion of cases. The subjective evaluation by the patients is in agreement with the stability and fusion achieved.

[Seat-belt and chance fractures of the thoracolumbar spine]

INTRODUCTION

The authors have attempted to elucidate the differences between Chance, seat-belt, and flexion distraction fractures. Chance and seat-belt fractures have more common features, while flexion distraction fractures differ, in particular, due to the mechanism of injury. A difficult diagnosis is sometimes a common characteristic, while therapy is always the same.

PATIENTS AND METHODS

During the period from 1997 to 2005, the authors treated 23 seat-belt fractures, and only three "genuine" Chance fractures. All patients had normal neurological findings. The mechanisms of injury were a car crash in 20 cases, and a fall associated with flexion in 6 cases, such as a rolling fall while skiing. According to the localisation, Chance fractures were found at the L 1 level twice and at the L 2 level once. Seat-belt injury was found once each in the areas of T 7, L 4, L 5, -twice at L 2 and L 3, and 16 times at the T / L spine transition, respectively. All patients were operated on using instrumented posterolateral spondylodesis.

RESULTS

All fractures healed by spondylodesis as confirmed by X-ray images. All patients returned to their original job or school. 14 patients were evaluated 6 months after removal of the metallic implants. The mean subsequent kyphotisation was 1.4 degrees with the largest deviation of 4 degrees in a patient with a pure ligamentous variant of a seat-belt fracture.

CONCLUSION

The objective of this work is to illustrate the various types of spinal distraction injuries of a seat-belt character and Chance fracture, when the vertebral body is not compressed. X-rays and often also CT scans show a "benign" character. Interpretation of the findings is very important for the development of further chronic instability of the spine and all consequences. If the diagnosis of a distraction injury is made the operative stabilisation is essential. That is why all our patients were tretaed by operation.

[Long-term results of calcaneal fracture treatment by open reduction and internal fixation using a calcaneal locking compression plate from an extended lateral approach]

PURPOSE OF THE STUDY

To report on the surgical treatment of intra-articular calcaneal fractures by open reduction and internal fixation with a calcaneal locking compression plate (LCP) from an extended lateral approach, and to retrospectively analyze the mid-term results in a group of patients treated by this technique.

MATERIAL

In the period from August 2005 till March 2007, a total of 49 patients with 61 calcaneal fractures were treated. Of these, 11 (18 %) were treated conservatively. Reduction combined with Kirschner-wire fixation was used in four fractures (6.6 %). Open reduction with internal calcaneal LCP fixation (ORIF- calcaneal LCP) from an extended lateral approach was carried out to treat 46 fractures (75.4 %) in 38 patients. The group evaluated here comprised 29 patients with 33 calcaneal fractures treated by ORIF-calcaneal LCP at a follow-up longer than 6 months. The fractures were classified on the basis of computer tomography (CT) findings as Sanders types I to IV. The group had two woman (6.9 %) and 27 men (93.1 %) with an average age of 34.2 years (range, 19-55 years). In 11 fractures (33.3 %), the primary treatment included filling a central cancellous bone defect area. Calcium phosphate bone substitute material (resorbable ChronOS) was used in nine cases (27.3 %), a self-solidifying hydroxyapatite implant was injected in two (6.1 %) cases (X3 Wright and Norian SRS, respectively), and a bone allograft was implanted in one case (3 %).

METHODS

Indicated for surgery were patients with an intra-articular calcaneal fracture, Sanders type II or type III, with articular surface displacement by more than 1 mm. Contraindications included age over sixty years, poor cooperation, smoking habits, peripheral vascular disease or skin infection. Surgery was performed only after oedema had resolved. The aim of our treatment was to achieve anatomical reconstruction of all articular surfaces, to restore the height, length, width and axis of the heel bone, to carry out primary stable osteosynthesis, and to enable the patient to begin rehabilitation with early mobilization. A passive rehabilitation usually started on the first post-operative day, and full weight-bearing of the extremity was allowed not earlier than 3 months post-operatively. Regular check-ups were at 6 weeks, 3, 6 and 12 months and then every year. The mid-term results were evaluated by the system of Rowe et al., scoring rest pain, possibility of return to preinjury jobs, use of walking aids, restriction of physical activity and limping. RESULTS The most frequent cause of injury was a fall or jump from height; this was recorded in 27 patients (93.1 %). An open fracture was diagnosed on two occasions (6.9 %). Bilateral calcaneal fractures were found in six patients (20.7 %); four (13.8 %) were treated by bilateral ORIF-calcaneal LPC and two (6.9 %) underwent closed reduction on one and Kirschnerwire transfixation on the other extremity. A combined injury to the musculoskeletal system was diagnosed in 11 patients (38 %), in whom four (13.8 %) had a tibial pylon fracture of the contralateral limb and four (13.8 %) had a thoracolumbar spine fracture. The surgical procedure was performed on average within 11.7 days of injury, and the average hospital stay was 18.2 days (range, 6 to 18 days). Early post-operative complications were recorded in six patients (20.7 %). Wound dehiscence was found in two (6.9 %), necrosis of wound edges in two (6.9 %), and early superficial infection responding to antibiotic therapy also in two patients (6.9 %). Deep infection, non-union or post-operative compartment syndrome were not recorded. Excellent Rowe scores were achieved in 10 patients (34.5 %), good in 15 (51.7 %) and satisfactory in two (6.9 %). Only two patients (6.9 %) reported poor outcome.

DISCUSSION

The methods of classification and treatment of calcaneal fractures continue to be a frequently discussed topic. The technique of ORIF-calcaneal LCP from an extended lateral approach has recently been preferred for patients with displaced Sanders type II or III calcaneal fractures. In agreement with other literature references, this approach allowed us to observe the fracture, to reduce both the subtalar and calcaneocuboid articulations, to stabilize the fracture by internal fixation and to begin early rehabilitation. Because of the risk of early complications, the timing of surgery and a thorough consideration of indications and contraindications are of principal importance.We agree with other authors that filling calcaneal bone defects is not necessary. Pre- and post-operative CT scans are necessary. In accordance with literature data, fractures developing compartment syndrome are indicated for urgent fasciotomy and ORIF-calcaneal LCP should be postponed. In patients with multiple trauma and also in those with open calcaneal fractures, a temporary stabilization with an external fixator medially is performed first, and then converted to a second-stage, ORIF-LCP procedure.

CONCLUSIONS

The surgical treatment of displaced intra-articular fractures that involves open reduction from an extended lateral approach and internal fixation with a calcaneal LCP shows very good preliminary results. A CT examination is required for the diagnosis and classification of fractures and a correct indication for surgery. Good timing is of principal importance. An urgent surgical intervention is necessary in open fractures or in those in which soft tissues are squashed by bone fragments. In the other fractures, surgery is carried out after oedema subsidence. Foot compartment syndrome is a serious complication of calcaneal fractures and urgent fasciotomy is the only adequate therapy. Full weight-bearing of the operated extremity depends on the rate of bone healing; it is usually allowed at 3 months after surgery.

Activities of respiratory chain complexes and pyruvate dehydrogenase in isolated muscle mitochondria in premature neonates

BACKGROUND AND AIMS

Most diseases in premature neonates are secondary to immaturity of various organ systems. Also the inadequate capacity of mitochondrial energy production may play an important role in the neonatal morbidity.

SUBJECTS AND METHODS

The activities and amount of respiratory chain (RC) complexes, pyruvate dehydrogenase (PDH) and citrate synthase (CS) were analysed in isolated muscle mitochondria obtained at autopsy in 19 premature neonates using spectrophotometric and radioenzymatic methods and blue-native electrophoresis and Western blotting. Two groups of children recommended for muscle biopsy at the age of 0.5-2 and 3-18 years served as controls.

RESULTS

In premature neonates, the activities of RC complexes III, IV, PDH and CS were markedly lower in comparison with older children. On the contrary, the activity of complex I was higher in premature neonates than in older children. The ratios between RC complexes I, II and III and CS were significantly higher in premature neonates in comparison with older children. In addition, the protein amount of RC complexes and PDH subunits were lower in premature neonates in comparison with older children.

CONCLUSION

The results of our study document the age-dependent differences in activities of PDH and respiratory chain complexes in early childhood. Lower functional capacity of mitochondrial energy-providing system in critically ill neonates may be explained by combination of various factors including the delay in maturation of PDH and respiratory chain complexes in very premature neonates and increased degradation of mitochondrial proteins in connection with sepsis, tissue hypoperfusion or hypoxemia.

Prolonged impairment of polymorphonuclear cells functions in one infant with transient zinc deficiency: a case report

BACKGROUND

Zinc is an essential trace element for the immune system. The zinc deficiency diminishes antibody- and cell-mediated responses in man. Lymphopenia and thymic atrophy are usually the early hallmarks of zinc deficiency. Surprisingly, only scarce data are available about polymorphonuclear cells (PMNs) functions in infants with zinc deficiency. We present the results of immunological analyses in one infant with transient zinc deficiency due to decreased zinc concentration in mother milk resulting in severe lactogenic acrodermatitis enteropathica.

MATERIAL/METHODS

Nine repeated examination of oxidative burst of PMNs and immunoglobulin levels using nitroblue tetrazolium dye test, chemiluminescence, flow cytometry and nephelometry were performed in the infant with severe zinc deficiency during 28 months period.

RESULTS

The unusual prolonged but transient impairment of PMNs respiratory burst accompanied with hypogammaglobulinaemia developed since the age of 2.5 months. Dramatic improvement of the skin was observed within days with total resolution of skin lesions on the 9th day of zinc therapy, but decreased PMNs respiratory burst persisted until the age of 23 months.

CONCLUSIONS

We conclude that zinc deficiency may lead to prolonged impairment of polymorphonuclear cells functions and hypogammaglobulinaemia.

The developmental changes in mitochondrial DNA content per cell in human cord blood leukocytes during gestation

The mitochondrial DNA (mtDNA) amount in cells as the basis for mitochondrial energy generating system, which produces ATP, plays an important role in the fetal development and postnatal morbidity. Isolated human cord blood leukocytes (HCBL) contribute very little to the overall metabolic turnover, but they may serve as easily available marker cells for the study of the mtDNA amount changes in cord blood during fetal development. The aim of our study was to analyze the mtDNA amount in HCBL. HCBL were isolated from cord blood samples of 107 neonates born between the 25th and 41st week of gestation. The mtDNA amount was analyzed by the real-time PCR method. The significant negative correlations were found between the relative mtDNA amount in HCBL and gestational age (r = -0.54, p<0.01) and birth weight (r = -0.43, p<0.01), respectively. The results revealed that the mtDNA content per cell decreases in HCBL with progressing fetal development. This may be explained by gradual shift of the hematopoiesis from fetal liver to bone marrow during the second half of pregnancy presumably accompanied by decreasing cell volume of HCBL as it was shown similarly in red blood cells.

[Unilateral lumbosacral dislocation]

The authors present a very uncommon case of unilateral lumbosacral dislocation. Twenty two similar cases have been published in the literature so far. Most of them occurred due to the flexion mechanism of injury, in our case the injury was caused by a combination of hyperextension and subsequent flexion with rotation. This rare injury can create diagnostic dilemma and in relation to complexity of soft tissue lesion we propose early circumferential instrumented fusion of lumbosacral region.

Biogenesis of eukaryotic cytochrome c oxidase

Eukaryotic cytochrome c oxidase (CcO), the terminal component of the mitochondrial electron transport chain is a heterooligomeric complex that belongs to the superfamily of heme-copper containing terminal oxidases. The enzyme, composed of both mitochondrially and nuclear encoded subunits, is embedded in the inner mitochondrial membrane, where it catalyzes the transfer of electrons form reduced cytochrome c to dioxygen, coupling this reaction with vectorial proton pumping across the inner membrane. Due to the complexity of the enzyme, the biogenesis of CcO involves a multiplicity of steps, carried out by a number of highly specific gene products. These include mainly proteins that mediate the delivery and insertion of copper ions, synthesis and incorporation of heme moieties and membrane-insertion and topogenesis of constituent protein subunits. Isolated CcO deficiency represents one of the most frequently recognized causes of respiratory chain defects in humans, associated with severe, often fatal clinical phenotype. Here we review recent advancements in the understanding of this intricate process, with a focus on mammalian enzyme.

[Vertebral body replacement with a Synex implant]

AIM

The authors assessed options for vertebral body replacements with the Synex telescopic expansion cage. Autologic or homologic bone grafts, a titanium "Harm's" cage or a polymethylmetacrylate filling reinforced by Kirschner wires, may be used for vertebral body replacements. The cement filling is indicated in oncological patients, the Harm's cage requires filling with a quantity of bone grafts and, with massive bone grafts, the collection place or the graft availability may be a problem. The telescopic expansion implant is fairly easy to implant, is stable and requires to be filled with a minimum of spongious grafts.

MATERIAL

From May 2001 to November 2005, 20 telescopic Synex cages were implanted in 18 patients. Vertebral body replacements were performed 14x for acute fractures, 4x for posttraumatic kyphosis and 2x for metastatic skeletal disorder in breast and prostate tumors.

METHODS

Vertebral body replacement was completed with posterior transpedicular stabilization in 14 subjects, in 5 subjects, additional anterior Ventrofix stabilization was performed. Vertebral body replacements down to the L1 level were conducted through thoracotomy or video-assissted minithoracotomy, L2-L4 replacements from lumbotomy or anterior retroperitoneal approach.

RESULTS

The most requently affected and operated vertebrae included the L1 (4 patients), Th12 (4 patients), Th6 (3 patients). The minimal interval between the procedure and a follow- up was 12 months. No fatal outcome has been recorded. In one patient with a vertebral body metastasis, the disorder has generalized and in a second one, no further metastatic spread has been reported. In one subject, the left-sided L4 root injury was recorded postoperatively, a cauda equina syndrome, diagnosed after the injury, persits in one subject. No signs of deep infection have been recorded. There are no records of the Synex release or displacement. Correction loss (kyphotisation) of up to 2 degrees was recorded in patients with transpedicular stabilization, in Ventrofix patients the loss was up to 5 degrees, except one case, where the loss reached 10 degrees.

DISCUSSION

One of the commonest indications for the anterior approach surgical stabilization of the spine, is the vertebral body destruction in burst fractures or posstraumatic kyphotizations of the spinal column. Unhealed or poorly healed type A and B (AO classification) pincer vertebral body fractures are other common indications for partial corpectomy and vertebral body replacements. Such fractures can be managed using posterior transpedicular stabilization. However, provided the procedure results in insufficient fracture repositioning, the anterior procedure and the anterior column reconstruction must be performed. A vertebral body can be replaced by a bone graft, a cement filling with Kirschner wiring, a traditional Harm's cage or an expansion implant. The bone graft may be autologic, which involves a disadvantage of the "donor site pain", or homologic, although a potential for reconstruction is not fully evidenced here. Implant migration into the vertebral body has been recorded in the classical titanium Harm's cage with a sharp edge without an additional endplate. Furthermore, it is a rather complicated implantation, requiring an exact implant size, which is considered another disadvantage. The expansion implant may be expanded telescopically in the very place, which is considered its biggest advantage. Furthermore, it need not be filled with bone grafts, but is applied only ventrally or laterally to the cage.

CONCLUSION

The Synex titanium expansion implant has been designed for vertebral body implantations in any indication. It requires additional stabilization, either by an anterior fixator or a cast, or a posterior transpedicular fixation. It is primarily indicated in traumatic vertebral body destructions or in reconstructions of maltreated fractures. Considering its higher price and the expected shorter patient survival period in oncological patients, its use in oncological indications is controversial.

X-linked dominant chondrodysplasia punctata (CDPX2): multisystemic impact of the defect in cholesterol biosynthesis

Chondrodysplasia punctata represents clinically and genetically a heterogeneous group of disorders characterized by the presence of multiple congenital anomalies and stippled epiphyses. We present clinical course of the disease and the results of metabolic, X-ray and molecular analyses in 19-months old girl with X-linked dominant chondrodysplasia punctata with intrauterine growth retardation, craniofacial dysmorphy, cataracts, cutaneous anomalies including ichthyosis, asymmetric rhizomesomelic shortness of the limbs, deformity of the spine, club foot, polydactyly, syndactyly, epiphyseal stippling and low cholesterol (2.29 mmol/l). Spectrophotometric analysis revealed the presence of abnormal pattern of cholesterol precursors in blood. The increased level of 8-dehydrocholesterol (42.2 micromol/l, controls < 1) and 7-dehydrocholesterol (25.5 micromol/l, controls < 1) recognised with GC/MS suggested an endogenous defect of cholesterol biosynthesis. The diagnosis of X-linked dominant chondrodysplasia punctata (CDPX2) was confirmed by the molecular analysis. Sequencing of the EBP gene encoding for 3beta-hydroxysteroid-delta8,delta7-isomerase revealed the presence of "de novo" heterozygous mutation c.327C>T (p.Arg110Stop). High cholesterol diet normalized cholesterol level (3.28 mmol/l) but it had no influence on the unfavourable prognosis of the disease. Low level of cholesterol with abnormal sterol profile in a child with congenital development anomalies represent an important laboratory marker suggesting an inherited defect of cholesterol biosynthesis.

[Rett syndrome: clinical and molecular aspects]

Rett syndrome is one of the leading causes of mental retardation and developmental regression in girls. It is characterized by a period of normal psychomotor development followed by the loss of acquired motor and communication skills, autistic features and stereotypic hand movements. Rett syndrome is the first pervasive developmental disorder with a known genetic cause. The majority of cases are caused by de novo mutations in an X-linked MECP2 gene. Its product, methyl-CpG-binding protein 2, plays an important role in the regulation of gene expression and chromatin structure. Because the neuropathology of Rett syndrome shares certain features with other neurodevelopmental disorders, a common pathogenic process may underlie these disorders. This makes Rett syndrome a prototype for the genetic, molecular, and neurobiological analyses of neurodevelopmental disorders.

A new mutation within the porphobilinogen deaminase gene leading to a truncated protein as a cause of acute intermittent porphyria in an extended Indian family

Based on Internet search, we were contacted by a 50-year-old man suffering from severe abdominal pain. Acute hepatic porphyria was considered from positive Watson-Schwartz test. He, not being a health professional, searched for centres with ability to do molecular diagnosis and for information about therapeutic possibilities. He asked his physician for haem-arginate (Normosang, Orphan Europe, Paris) treatment, arranged sending his blood to our laboratory and mediated genetic counselling for him and his family. Molecular analyses of the PBGD gene revealed a novel mutation in exon 15, the 973insG. Subsequently, genetic analysis was performed in 18 members of the proband's extensive family. In 12 members of the family, the same mutation was found. The mutation, which consisted of one nucleotide insertion, resulted in addition of four different amino acids leading to a protein that is prematurely truncated by the stop codon. The effect of this mutation was investigated by expression of the wildtype and mutated PBGD in a prokaryotic expression system. The mutation resulted in instability of the protein and loss of enzymatic function. The increasing access to a number of disease- and symptom-oriented web pages presents a new and unusual venue for gaining knowledge and enabling self-diagnosis and self-help. It is, therefore, important that diseaseoriented Internet pages for public use should be designed with clarity and accurate current knowledge based background.

Deficiency of mitochondrial ATP synthase of nuclear genetic origin

We present clinical and laboratory data from 14 cases with an isolated deficiency of the mitochondrial ATP synthase (7-30% of control) caused by nuclear genetic defects. A quantitative decrease of the ATP synthase complex was documented by Blue-Native electrophoresis and Western blotting and was supported by the diminished activity of oligomycin/aurovertin-sensitive ATP hydrolysis in fibroblasts (10 cases), muscle (6 of 7 cases), and liver (one case). All patients had neonatal onset and elevated plasma lactate levels. In 12 patients investigated 3-methyl-glutaconic aciduria was detected. Seven patients died, mostly within the first weeks of life and surviving patients showed psychomotor and various degrees of mental retardation. Eleven patients had hypertrophic cardiomyopathy; other clinical signs included hypotonia, hepatomegaly, facial dysmorphism and microcephaly. This phenotype markedly differs from the severe central nervous system changes of ATP synthase disorders caused by mitochondrial DNA mutations of the ATP6 gene presenting mostly as NARP and MILS.

Fumaric aciduria: mild phenotype in a 8-year-old girl with novel mutations

Fumaric aciduria is a rare, autosomal recessive disorder caused by deficient activity of fumarate hydratase (FH). Common clinical features are hypotonia, failure to thrive, severe psychomotor retardation and seizures. Facial dysmorphism and brain malformations are frequent. Recently, some FH gene mutations have been associated with inherited cutaneous and uterine leiomyomas and papillary renal cell cancer. Our patient had a relatively mild phenotype, a previously not reported genotype and familial tumour predisposition. The mother and grandmother had uterine myomas. The paternal grandfather and his two brothers died from lung and laryngeal cancers. The pregnancy was complicated by bleeding and intrauterine growth retardation. Delivery was after 35 weeks, with normal Apgar score. The girl was hypotonic since birth. At age 2 months the parents noticed short apnoeic crises. She could sit at age 1.5 years, and walk with assistance at 4 years. At age 8 years highly increased excretion of fumaric acid was found twice (217 and 445 mmol/mol creatinine). Shortly before that the girl started to have leg and arm spasms. Grand mal seizures occurred twice. Facial dysmorphism included depressed nasal bridge, anteverted ears, hypertelorism and microcephaly. Speech was limited to few disyllables. She was atactic with spastic paraparesis. Brain MRI showed slight ventriculomegaly, white-matter atrophy and hypoplasia of corpus callosum. Activity of FH in fibroblasts was 1.9 nmol/min/mg protein (controls 40-80). Analysis of the FH gene revealed the maternally derived c.1029_1031delAGT mutation, resulting in Val deletion and substitution of Gln by His, and paternally derived c.976C > T mutation, resulting in substitution of Pro by Ser.

Specific Properties of Heavy Fraction of Mitochondria from Human-term Placenta – Glycerophosphate-dependent Hydrogen Peroxide Production

Mitochondrial respiratory chain enzyme Complexes are present in placenta at proportion similar to other tissues with exception of glycerophosphate dehydrogenase (mGPDH) which is expressed at a very high rate. As shown by Western blot quantification and respiratory chain enzyme activity measurements, the specific content of mGPDH is similar to that of succinate dehydrogenase or NADH dehydrogenase. Using fluorometric probe dichlorodihydrofluorescein diacetate we found that placental mitochondria display high rate of glycerophosphate-dependent hydrogen peroxide production. This was confirmed by oxygraphic detection of glycerophosphate-induced, KCN- or antimycin A-insensitive oxygen uptake. Hydrogen peroxide production by mGPDH was highly activated by one-electron acceptor, potassium ferricyanide and it was depressed by inhibitors of mGPDH and by cytochrome c. Our results indicate that mGPDH should be considered as an additional source of reactive oxygen species participating in induction of oxidative stress in placenta.

[Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)]

BACKGROUND

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a disorder with autosomal recessive inheritance caused by mutations in the gene encoding thymidine phosphorylase (TP). TP deficiency results in imbalance of mitochondrial pool of nucleotides leading secondary to multiple deletions and depletion of mitochondrial DNA (mtDNA) and impairment of oxidative phosphorylation system. The disease is clinically characterized by gastrointestinal dysmotility with symptoms of pseudo-obstruction, severe failure to thrive, ptosis, leukoencephalopathy, peripheral neuropathy and myopathy. We present results of the clinical, histochemical, biochemical and molecular analyses of the first Czech patient with MNGIE syndrome.

METHODS AND RESULTS

Man, 33-years old with twenty-year history of failure to thrive (height 168 cm, weight 34 kg) and progressive gastrointestinal dysmotility, external ophthalmoplegia, leucoencephalopathy and peripheral neuropathy was recommended to metabolic center. Histochemical analyses in muscle biopsy showed the presence of "ragged red fibers" with focal decrease of cytochrome c oxidase activity, but spectrophotometric analyses in isolated muscle mitochondria revealed normal activities of all respiratory chain complexes. Metabolic investigation revealed markedly increased plasma level of thymidine (6.6 micromol/l, controls <0.05 micromol/l) and deoxyuridine (15 micromol/l, controls <0.05 micromol/l). The activity of TP in isolated lymphocytes was low (0.02 micromol/hour/mg protein, reference range 0.78 +/- 0.18). Molecular analyses in muscle biopsy revealed multiple mtDNA deletions and homozygous mutation 1419G>A (Gly145Arg) was found in gene for TP. Both parents are heterozygotes.

CONCLUSIONS

MNGIE has to be considered in patients presenting with a combination of gastrointestinal and neurological symptoms. Plasma level of thymidine may serve as the best method for laboratory screening of MNGIE, but molecular analyses are necessary for genetic counselling and prenatal diagnosis in affected families.

[History of foster care in the Czech Republic]

"The enlightment period" in the second half of the 18th century brought new view on the negative results of the institutional care in orphanages. The aim to improve the care of orphans and unattended children in the region of former Austrian Empire resulted in the year 1789 in the new law about the foster care. The law incorporated ten principles how to provide, control and finance the foster care in our region.

Epidemiology of severe sepsis in intensive care units in the Slovak Republic

BACKGROUND

We investigated the number, clinical characteristics, and outcomes of ICU patients, who met precise clinical and physiological criteria for severe sepsis (as defined in the PROWESS study) in Slovak intensive care units. We designed an observational cohort epidemiological study with retrospective analysis of prospectively collected data. 12 adult general intensive care units participated in the Slovak Republic between July and December 2002.

PATIENTS AND METHODS

Patients included 1,533 adult ICU admissions during the second half of 2002 in 12 adult ICUs. Descriptive statistical methods (independent sample T-test, chi(2) test, and linear Pearson coefficient of correlation) were used.

RESULTS

We found that 7.9% of hospitalized critically ill patients met severe sepsis criteria in the intensive care units. The most frequent primary sources of infection were lungs and abdomen. Hospital mortality of severe septic patients was 51.2% (62 pts/121 pts). Most patients (85.1%) were > 40 years of age. Mortality increased with age; mean average age of survivors (53 years) was significantly lower than in nonsurvivors (61 years, p = 0.01). Factors associated with mortality were age over 50 years, three or more dysfunctional organs, and elevated admission and maximum SOFA scores. Survivors had a significantly lower number of sites with organ system dysfunction (MODS 2.56) than nonsurvivors (MODS 3.98). SOFA score seems to be a valuable tool to differentiate survivors from nonsurvivors. All the septic patients had SOFA scores greater than 4 points. Survivors of severe sepsis were characterized with significantly lower admission and maximum SOFA scores (median 8.7 and 9.4 points, respectively) than septic nonsurvivors (median 11.6 and 14.0 points, respectively, p = 0.001).

CONCLUSION

We estimate 1,770 cases of severe sepsis hospitalized at Slovak adult intensive care units per year. Hospital mortality for severe sepsis remains very high (51.2%) and is associated with advanced age (over 50 years), number of failing organs and higher admission and maximum SOFA scores.

Clinical, biochemical and molecular analyses of six patients with isolated cytochrome c oxidase deficiency due to mutations in the SCO2 gene

BACKGROUND AND AIM

Cytochrome c oxidase (COX) deficiency represents a heterogeneous group of disorders. Numerous proteins are required for efficient COX assembly and maintenance. In 26 children with isolated COX deficiency, we studied mutations in the SCO2 gene, which is involved in the copper transport into the inner mitochondrial membrane, and we analysed the clinical and biochemical consequences of SCO2 mutations.

METHODS

The activities of respiratory chain complexes were measured spectrophotometrically in isolated mitochondria and/or crude cell extracts in all available tissues. Two-dimensional polyacrylamide electrophoresis (2D-PAGE) was used to separate the complexes and their subunits. The mutations were detected by sequencing and RFLP analysis.

RESULTS

Mutations in the SCO2 gene were found in six children. Early neonatal onset of hypertrophic cardiomyopathy and encephalopathy were observed in one boy with compound heterozygous mutations C1280T and G1541A. In all five children with homozygous mutation G1541A, progressive encephalopathy developed between 2 and 6 mo of age. Isolated COX deficiency was found in the skeletal muscle, heart, liver and brain but not in fibroblasts. 2D-PAGE in the skeletal muscle showed markedly decreased amounts of all COX subunits.

CONCLUSION

Our results suggest that mutations in the SCO2 gene are not rare, at least in our population. Although clinical symptoms may rely on the type of SCO2 mutation, the prognosis is unfavourable in all patients.