T1 Vertebra Pedicular Osteoid Osteoma: Minimally Invasive Surgical Resection Aided by New Integrated Navigation to 3D Imaging Device.

We hereby describe a minimally invasive resection of a T1 pedicular osteoid osteoma next to the vertebral canal. The patient had an 18-month report of painful radiculopathy. We performed the surgery under 3D imaging guidance using navigation with an all-in-one device. Full procedure irradiation was 1.17 mSv for a 181-picture acquisition. Complete operative time incision to closure was 58 minutes. Despite sparing the vertebral stability without any fixation, the tumor resection was well-margined, thanks to the focused guidance. After surgery, the patient had complete relief of his symptoms at the 6-month follow-up. 3D imaging system coupled to navigation made the procedure safe without consuming time. The single Surgivisio® device allows comfortable 3D minimally invasive spine navigation surgery with the ergonomics of a C-arm.

Intraoperative 2D C-arm and 3D O-arm in children: a comparative phantom study.

PURPOSE: Exposure to ionizing radiation is a concern for children during intraoperative imaging. We aimed to assess the radiation exposure to the paediatric patient with 2D and 3D imaging. METHODS: To evaluate the radiation exposure, patient absorbed doses to the organs were measured in an anthropomorphic phantom representing a five-year-old child, using thermoluminescent dosimeters. For comparative purposes, organ doses were measured using a C-arm for one minute of fluoroscopy and one acquisition with an O-arm. The cone-beam was centred on the pelvis. Direct and scattered irradiations were measured and compared (Student's t-test). Skin entrance dose rates were also evaluated. RESULTS: All radiation doses were expressed in µGy. Direct radiation doses of pelvic organs were between 631.22 and 1691.87 for the O-arm and between 214.08 and 737.51 for the C-arm, and were not significant (p = 0.07). Close scattered radiation on abdominal organs were between 25.11 and 114.85 for the O-arm and between 8.03 and 55.34 for the C-arm, and were not significant (p = 0.07). Far scattered radiation doses on thorax, neck and head varied from 0.86 to 6.42 for the O-arm and from 0.04 to 3.08 for the C-arm, and were significant (p = 0.02). The dose rate at the skin entrance was 328.58 µGy.s-1 for the O-arm and 1.90 with the C-arm. CONCLUSION: During imaging of the pelvis, absorbed doses for a 3D O-arm acquisition were higher than with one minute fluoroscopy with the C-arm. Further clinical studies comparing effective doses are needed to assess ionizing risks of the intraoperative imaging systems in children.

A Novel Minimally Invasive Reduction Technique by Balloon and Distractor for Intra-Articular Calcaneal Fractures: A Report of 2 Cases.

Treatment of displaced intra-articular fractures of the calcaneus remains a challenge for the orthopaedic surgeon. Conservative therapy is known to produce functional impairment. Surgical approach is plagued by soft-tissue complications and insufficient fracture reduction. We describe a minimally invasive technique that will hopefully improve these issues. We want to present our first experience through two cases. The first was a 46-year-old man who presented with a Sanders type IIBC calcaneal fracture, and the second was a 86-year-old woman with a type IIIBC calcaneal fracture. We introduced 2 Schanz screws in the talus and the calcaneus. After distraction, we introduced an inflatable balloon inside the calcaneus. By inflating the balloon, the articular surface was reduced by lifting it up. Then bone cement was injected in order to maintain the reduction. Additional screw fixation was used in the young patient. Postoperative imaging showed good congruence of the subtalar joint without leakage of cement, for the two cases. After 2 months, the patients had no pain and were without soft-tissue complications. We advocate this technique to perform a minimally invasive reduction and fixation of intra-articular calcaneal fractures because it preserves soft-tissues and provides good clinical results with early weight-bearing.

Cutaneous infection and bactaeremia caused by Erwinia billingiae: a case report.

Cellulitis and erysipelas are common skin infections usually caused by Staphylococcus aureus and streptococci. Gram-negative rods are rarely implicated. We report here a case of dermohypodermitis and bactaeremia caused by Erwinia billingiae, a Gram-negative bacteria usually pathogenic and epiphytic to pome fruit tree.

Amino acids and insulin are both required to regulate assembly of the eIF4E. eIF4G complex in rat skeletal muscle.

The respective roles of insulin and amino acids in regulation of skeletal muscle protein synthesis and degradation after feeding were examined in rats fasted for 17 h and refed over 1 h with either a 25 or a 0% amino acid/protein meal. In each nutritional condition, postprandial insulin secretion was either maintained (control groups: C(25) and C(0)) or blocked with diazoxide injections (diazoxide groups: DZ(25) and DZ(0)). Muscle protein metabolism was examined in vitro in epitrochlearis muscles. Only feeding the 25% amino acid/protein meal in the presence of increased plasma insulin concentration (C(25) group) stimulated protein synthesis and inhibited proteolysis in skeletal muscle compared with the postabsorptive state. The stimulation of protein synthesis was associated with increased phosphorylation of eukaryotic initiation factor (eIF)4E binding protein-1 (4E-BP1), reduced binding of eIF4E to 4E-BP1, and increased assembly of the active eIF4E. eIF4G complex. The p70 S6 kinase (p70(S6k)) was also hyperphosphorylated in response to the 25% amino acid/protein meal. Acute postprandial insulin deficiency induced by diazoxide injections totally abolished these effects. Feeding the 0% amino acid/protein meal with or without postprandial insulin deficiency did not stimulate muscle protein synthesis, reduce proteolysis, or regulate initiation factors and p70(S6k) compared with fasted rats. Taken together, our results suggest that both insulin and amino acids are required to stimulate protein synthesis, inhibit protein degradation, and regulate the interactions between eIF4E and 4E-BP1 or eIF4G in response to feeding.

Inhibition and habituation: preserved mechanisms of attentional selection in aging and Alzheimer's disease.

Are inhibition and habituation, processes that contribute to selective attention, impaired by aging or Alzheimer's disease (AD)? Younger adults, older adults, and adults with AD read lists of letters presented either alone or paired with distractor letters. Slower reading times for lists containing distractors relative to lists without distractors indexed concurrent interference (distraction). Slower reading times for lists in which distractors subsequently became targets relative to lists in which distractors and targets were unrelated indexed negative priming (inhibition). Faster reading times when distractors were constant in identity or location rather than random indexed repeated distractor effects (habituation). Distraction increased with aging and AD, whereas inhibition and habituation showed no age- or AD-related decline, suggesting that inhibition and habituation still function to aid attentional selection in older adults and adults with AD.

Distribution of the various radiation-induced chromosomal rearrangements in relation to the dose and sampling time.

The quantitative analysis of the chromosome rearrangements detected in 2128 R-banded metaphases, obtained from gamma-irradiated human lymphocytes after 48 to 96 h in culture is reported. Depending on the culture time, and possibly on the dose of radiation (from 1 to 3 Gy), the most frequent type of rearrangement was either dicentrics or reciprocal translocations. In first generation mitoses, the frequency of cells without rearrangement ranged from 0.66 to 0.18, and the mean number of rearranged chromosomes per cell from 0.79 to 3.28. The dose-response curve follows a quadratic function for dicentric aberration yields, but not for other rearrangements.

[Chromosomal phylogeny of Gerbillidae. III. Species study of the genera Tatera, Taterillus, Psammomys and Pachyuromys]. / Phylogénie chromosomique des Gerbillidae. III. Etude d'espèces des genres Tatera, Taterillus, Psammomys et Pachyuromys.

The karyotypes of six species of Gerbillidae (Rodentia)--Taterillus congicus, Tetarillus sp d'Oursi, Tatera sp cf. nigrita, Tatera guineae, Psammomys obesus, and Pachyuromys duprasi--are described and compared to those of species already studied. Many chromosomal homoeologies are demonstrated, as well as the existence of many rearrangements. Some genera, e.g., Taterillus, have undergone a very complex chromosomal evolution, while others have kept their karyotypes fairly close to that of the common ancestor.

Characterisation of a very complex constitutive heterochromatin in two Gerbillus species (Rodentia).

A large amount of heterochromatin is observed in two species of the genus Gerbillus, G. nigeriae and G. hesperinus. The C-band material represents about one-half of the total karyotype length in the former species, and about one-third in the latter. Several banding techniques and various 5-bromodeoxyuridine (BrdU) treatments were used to characterise these heterochromatic segments. After applying the R-banding technique, three different staining responses of the heterochromatin can be distinguished. In G. nigeriae, strongly stained segments (R-band positive) appear in most chromosomes and, in particular, constitute the short arms of all the larger chromosomes. Palely staining heterochromatic segments (R-band negative) are less abundant in G. nigeriae but predominate in G. hesperinus. In addition, in both species an intermediate staining of heterochromatin is observed near the centromere or in the heterochromatic short arms of some acrocentric and small submetacentric chromosomes. Very short BrdU treatment during the end of the last cell cycle results in asymmetrical staining of chromatids in heterochromatic segments after applying the acridine orange or FPG (fluorescence plus Giemsa) technique. The alternating location of strongly staining segments in one or the other chromatid simulates sister chromatid exchanges ("pseudo-SCE"). This pattern persists after longer BrdU treatment during different stages of the last cell cycle and is independent of the R-staining properties of the heterochromatin. The lateral asymmetric appearance of the large heterochromatic segments in Gerbillus is interpreted as reflecting an uneven distribution of adenine and thymidine between the two strands of DNA.

Risk of chromosomal disease due to radiation. Tentative estimate from the study of radiation-induced translocations in human fibroblasts.

A sample of 214 reciprocal 2-break translocations observed in fibroblasts, both after accidental 'in vivo', and experimental 'in vitro' gamma-irradiation, was studied. The distribution of the breaks along the chromosomes does not seem at random. The minimal possible imbalance that these translocations could induce by malsegregation, if they existed in germ cells, was estimated. These imbalances were compared with the chromosomal trisomies and monosomies known to be compatible with life after birth in man. It is concluded that about 2/5 of the radiation-induced translocations might induce a viable trisomy and/or monosomy. This result, similar to that previously obtained in human lymphocytes, indicates the validity of the extrapolation from one tissue to another, and hopefully to germ cells.

Chromosomal phylogeny of Muridae: a study of 10 genera.

The karyotypes of 10 different species of the family Muridae (Acomys airensis, Arvicanthis niloticus, Hylomyscus stella, Malacomys longipes, Mastomys huberti, Myomys daltoni, Mus musculus, Rattus norvegicus, Thamnomys gazellae, and Uranomys ruddi) are compared by different banding techniques. From a reconstruction of the presumed ancestral karyotype of the Muridae the sequence of the various rearrangements leading to the present karyotypes is proposed in order to determine their phylogenetic relationships. In particular, the present karyotypes of the mouse and rat differ from the ancestral one by at least 12 and 7 rearrangements, respectively. A clear tendency for accumulation of a specific type of rearrangement in a given branch of the cladogram is observed. In regard to the mouse, a large number of translocations, with break points situated in the proximal part of the long arms, have occurred, which conserved the acrocentric form of the ancestral chromosomes but led to multiple recombinations of the bands.

Tentative estimate of the risk of chromosomal disease due to radiation-induced translocations in man.

An attempt to estimate one of the parameters establishing the risk of occurrence of abnormal live-born progeny by malsegregation of radiation-induced translocation is reported. A sample of 247 2-break translocations induced by gamma-rays in human lymphocytes was studied in relation to the minimal possible imbalance they could induce in gametogenesis. These imbalances were compared with chromosomal trisomies and monosomies known to be compatible with life after birth in man. It is concluded that at least 106 out of 247 translocations should not give viable products in cases of malsegregation. A second comparison, with translocations ascertained in human subjects for various reasons, led to the conclusion that about 2/5 of the radiation-induced translocations might involve a risk of partial trisomies or monosomies. Cell survival and frequency of meiotic malsegregations are other parameters needed to make a correct estimate. A short discussion shows the difficulty of such estimates from inter-specific comparisons.