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Background: The hardness of kernels determines the dry-milling processing performance of maize hybrids. The identification of the best maize hybrids for the dry-milling process requires a limited number of simple, practical and reliable tests that are able to predict the potential grit yield., Results: A total of 119 samples from different genetic and environmental backgrounds, collected over 3 years, were analysed for coarse/fine ratio (C/F), floating test (FLT), protein content (PC), kernel sphericity (S), total milling energy (TME) and test weight (TW). The total grit yield (TGY) of each sample was obtained through a micromilling procedure based on the manual separation of kernel endosperm followed by grinding and sieving under standard operational conditions. The TGY was used to establish the capability of the tests to predict the dry-milling aptitude. Single and multiple linear regression analyses were performed to establish equations for the prediction of TGY using C/F, FLT, PC, S, TME and TW as independent variables. The analyses were performed on three data sets, clustered year by year of the sample collection and analysis, and the resulting average coefficients of determination (R(2)) were compared by analysis of variance. C/F, FLT, TME and, to a lesser extent, TW appeared to be easy-to-use independent descriptors of maize dry-milling. An improved model prediction ability was observed when different combinations of a few physical and chemical properties were used as input variables. However, the models in which three or more variables were used did not lead to any significant improvement in TGY prediction compared with the smaller models., Conclusion: This study contributes towards establishing the best predictor of maize kernel aptitude to dry-milling processes. Of all considered data sets, a milling evaluation factor (C/F or TME) coupled with kernel density (measured by means of the FLT) showed the best predictive ability for dry-milled product yields., (© 2012 Society of Chemical Industry.)

Purpose: To investigate changes of corneal power after descemet stripping automated endothelial keratoplasty (DSAEK)., Methods: Anterior, posterior, and true-net (anterior + posterior) power of post-DSAEK and contralateral transparent corneas were measured, using the Pentacam rotating Scheimpflug camera (Oculus Wetzlar, Germany), 6 months after surgery in 23 consecutive patients who had undergone unilateral DSAEK at the same medical center. Moreover, in each cornea, Pentacam pachimetry was measured at the vertex and at 3 mm from the vertex, to calculate corneal thickness increase (CTI)., Results: In post-DSAEK corneas, the anterior power on average decreased by -0.24 ± 0.61 diopters (D), the negative posterior power increased by -0.96 ± 0.42 D, and the true-net power decreased by -1.19 ± 0.74 D (range: +0.17 to -2.23 D). Differences vs. contralateral transparent corneas did not reach statistical significance for anterior (p = 0.09) but were significant (p < 0.001) for posterior and true-net corneal power. CTI at 3 mm from the vertex was statistically larger (p < 0.0001) in post-DSAEK corneas (mean values 0.27 ± 0.07 vs. 0.12 ± 0.05); CTI values showed a statistically significant (p < 0.05) correlation with negative posterior corneal power values in post-DSAEK (r = -0.55) and in contralateral corneas (r = -0.67)., Conclusions: In comparison with contralateral corneas, post-DSAEK corneas show a moderate reduction of the true-net corneal power measured by Pentacam. Knowledge of true-net corneal power changes might be useful in adjusting K values and calculating intraocular lens power, in eyes scheduled for DSAEK combined with intraocular lens implantation/exchange.

Amyloid-β (Aβ) plaque deposition can precede the clinical manifestations of dementia of the Alzheimer type (DAT) by many years and can be associated with changes in brain metabolism. Both the Aβ plaque deposition and the changes in metabolism appear to be concentrated in the brain's default-mode network. In contrast to prior studies of brain metabolism which viewed brain metabolism from a unitary perspective that equated glucose utilization with oxygen consumption, we here report on regional glucose use apart from that entering oxidative phosphorylation (so-called "aerobic glycolysis"). Using PET, we found that the spatial distribution of aerobic glycolysis in normal young adults correlates spatially with Aβ deposition in individuals with DAT and cognitively normal participants with elevated Aβ, suggesting a possible link between regional aerobic glycolysis in young adulthood and later development of Alzheimer pathology.

Oral rehabilitation for a patient with severe loss of alveolar bone and soft tissue resulting from severe periodontitis presents a challenge to clinicians. Replacing loosening natural teeth with fixed prostheses supported by dental implants often requires either gingival surgery or bone grafting. The outcome of the bone grafting is sometimes unpredictable and requires longer healing time and/ or multiple surgeries. The presence of periodontal inflammation and periapical lesions often delay the placement of bone grafts as well as dental implants. Here we present a clinical case of a patient undergone full mouth reconstruction with implant-supported fixed prostheses. We demonstrated that early placement of implants (three weeks after extractions) with minimal bone grafting may be an alternative to conventional bone grafting followed by implant placement. We believe that primary stability during implant placement may contribute to our success. In addition, composite resin gingival material may be indicated in cases of large fixed implant prostheses as an alternative to pink porcelain.

Objective: To report a novel cause of nocturnal enuresis (NE) and highlight the literature giving insight into this novel mechanism., Patient: A 12-year-old morbidly obese female with 2-year history of nightly secondary monosymptomatic NE., Results: On evaluation, a history of severe sleep disturbed breathing was elicited. Anticipating obstructive sleep apnea (OSA), polysomnography was performed, detecting severe central sleep apnea (CSA) without OSA. Brain magnetic resonance imaging revealed severe Chiari malformation Type I (CM1) with abnormal cerebrospinal fluid dynamics. She had no other classic signs or symptoms of CM1. Neurosurgical decompression halted the NE and normalized nocturnal breathing and cerebrospinal fluid dynamics, confirming that the CSA was caused by the CM1 and resulted in the NE. A thorough literature review found no prior reports of CSA-induced NE. Since CSA and OSA differ by the absence of negative intrathoracic pressures in CSA, this case suggests that such pressures are not a key mechanistic component of SA-induced NE., Conclusion: This first report of secondary NE caused by CSA from CM1 emphasizes obtaining a sleep history in the enuretic child, introduces a new cause of NE, and challenges hypotheses underlying SA-induced NE., (Copyright (c) 2010 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Object: The object of this study was to assess a multiinstitutional experience with pediatric occipitocervical constructs to determine whether a difference exists between the fusion and complication rates of constructs with or without direct C-1 instrumentation., Methods: Seventy-seven cases of occiput-C2 instrumentation and fusion, performed at 9 children's hospitals, were retrospectively analyzed. Entry criteria included atlantooccipital instability with or without atlantoaxial instability. Any case involving subaxial instability was excluded. Constructs were divided into 3 groups based on the characteristics of the anchoring spinal instrumentation: Group 1, C-2 instrumentation; Group 2, C-1 and C-2 instrumentation without transarticular screw (TAS) placement; and Group 3, any TAS placement. Groups were compared based on rates of fusion and perioperative complications., Results: Group 1 consisted of 16 patients (20.8%) and had a 100% rate of radiographically demonstrated fusion. Group 2 included 22 patients (28.6%), and a 100% fusion rate was achieved, although 2 cases were lost to follow-up before documented fusion. Group 3 included 39 patients (50.6%) and demonstrated a 100% radiographic fusion rate. Complication rates were 12.5, 13.7, and 5.1%, respectively. There were 3 vertebral artery injuries, 1 (4.5%) in Group 2 and 2 (5.1%) in Group 3., Conclusions: High fusion rates and low complication rates were achieved with each configuration examined. There was no difference in fusion rates between the group without (Group 1) and those with (Groups 2 and 3) C-1 instrumentation. These findings indicated that in the pediatric population, excellent occipitocervical fusion rates can be accomplished without directly instrumenting C-1.

Purpose: To define a method of stabilizing stones during extracorporeal (SWL) and intracorporeal lithotripsy with a thermosensitive polymer., Materials and Methods: Using a thermosensitive polymer that is either a liquid or a gel, depending on the temperature, both calcium oxalate and plaster of Paris phantom stones were placed in the polymer gel or saline, and SWL was performed. Comparisons were made between the effectiveness of the fragmentation in the two media. Also, in-vivo studies using the polymer to prevent migration of ureteral stones were performed in swine. Electrohydraulic lithotripsy was used on a small stone implanted in the distal ureter with the polymer instilled proximally. Once in the ureter, the polymer converted to a gel. After completion of the procedure, the polymer was restored to a liquid form by infusion of cold saline and expelled from the ureter. Three of the pigs underwent treatment of the stone, convalesced for 7 days, and then had urine collections from both ureters to compare the glomerular filtration rates, fractional sodium excretion, urine/plasma creatinine ratio, and urine/plasma urea ratio on the treated and the contralateral (control) sides., Results: The polymer did not enhance fragmentation when used with SWL but prevented stone migration in the in-vivo studies. The physiologic parameters were not significantly different on the treated and the control sides. The polymer was easily removed from the ureter by infusing cold water., Conclusion: The use of this thermosensitive polymer proximal to ureteral stones prevents migration and is not traumatic to the ureter.

Dentists are caring for an older population with significant comorbidities. It is necessary to be familiar with a patient's medical history and medications and how they may affect the care provided. This article focuses on patients with history of strokes or Alzheimer's disease.

A patient treated for nephrolithiasis formed knots in 2 occasions, in 2 separate indwelling ureteral stents. This rare complication may make stent removal difficult. To our knowledge, this is the first case report of repeat knot formation in a single patient.

Background: A robotically guided linear accelerator has recently been developed which provides frameless radiosurgery with high precision. Potential advantages for the pediatric population include the avoidance of the cognitive decline associated with whole brain radiotherapy, the ability to treat young children with thin skulls unsuitable for frame-based methods, and the possible avoidance of general anesthesia. We report our experience with this system (the "Cyberknife") in the treatment of 21 children., Procedures: Cyberknife radiosurgery was performed on 38 occasions for 21 patients, age ranging from 8 months to 16 years (7.0 +/- 5.1 years), with tumors considered unresectable. Three had pilocytic astrocytomas, two had anaplastic astrocytomas, three had ependymomas (two anaplastic), four had medulloblastomas, three had atypical teratoid/rhabdoid tumors, three had craniopharyngiomas, and three had other pathologies. The mean target volume was 10.7 +/- 20 cm(3), mean marginal dose was 18.8 +/- 8.1 Gy, and mean follow-up is 18 +/- 11 months. Twenty-seven (71%) of the treatments were single-shot and eight (38%) patients did not require general anesthesia., Results: Local control was achieved in the patients with pilocytic and anaplastic astrocytoma, three of the patients with medulloblastoma, and the three with craniopharyngioma, but not for those with ependymoma. Two of the patients with rhabdoid tumors are alive 16 and 35 months after this diagnosis. There have been no procedure related deaths or complications., Conclusion: Cyberknife radiosurgery can be used to achieve local control for some children with CNS tumors without the need for rigid head fixation., ((c) 2004 Wiley-Liss, Inc.)

Participatory action research (PAR) is an excellent way to systematically learn about the conditions under which people experience health disparities, what it is like from the perspective of those experiencing such disparities and, even more importantly, how to ameliorate this major public health problem and create a more equitable and effective health care system. This article describes the method of PAR, supports the appropriateness of PAR to learn about and reduce health disparities, and then presents some specific examples of research projects that have employed or are planning to employ PAR. These examples are from the work of several authors of this article, who are members of an interdisciplinary working group that serves as a forum for discussion of issues related to qualitative research methods and facilitates the development of qualitative studies. All of the authors of this article are part of a task force of this working group that is focusing specifically on community outreach with the goal of reducing health disparities within specific communities.

A. R. Luria introduced the interpretation of a meaningful picture as a tool for assessing pre-frontal impairment. We gave this test to 196 normal adults, who were asked to communicate what was happening in the portrayed scene (a boy chases a mouse hidden under a cupboard, while three frightened girls assist). The same subjects were given two other frontal tests (verbal fluency on phonemic cue and Trail Making Test (TMT)) and Raven's Matrices. Twenty-three normal subjects (12%) failed to correctly interpret the picture. We also examined 20 patients whose brain lesion encroached upon pre-frontal areas, in order to check if this version of the test could be easily administered to this type of patient, and if its difficulty level was appropriate for avoiding ceiling and floor effects. Twelve patients were unable to interpret the picture (60%). A similar failure rate was observed with the same subjects on verbal fluency and TMT, while Raven's Matrices were less impaired (35%). Some dissociation was found between Picture Interpretation and the TMT. The Italian version of the Picture Interpretation Test is suitable for the examination of pre-frontal patients.

Case Report: Twin boys joined at the head in a total vertex configuration were born in Egypt in June 2001. At 12 months, they were transported to Dallas for evaluation and eventual surgical separation. In Dallas, a large multidisciplinary team of health care providers from two pediatric hospitals was assembled to care for the boys. Extensive radiographic evaluation revealed that the twins had essentially separate, well-formed brains, each with regions of schizencephaly. Each child's left cerebral hemisphere drained most of the venous blood to the right jugular system of the other. A detailed assessment of the foreseeable risks of surgical separation was then estimated and presented to the parents, as well as to the ethics committee of the two institutions. The decision was then made to proceed with separation. Surgical planning included the construction of multiple polymer models, and the design and construction of customized head holders and an operating table. Prior to separation a series of preparatory operations were performed to expand the scalp, as well as the fascia lata for dural grafting. At the age of 28 months, the twins were successfully separated during a 33-h operation. No attempt was made to reconstruct the dural venous sinuses. Scalp closure was adequate, requiring a split-thickness skin graft on one boy., Outcome: Postoperatively each child demonstrated an incomplete right hemiparesis. One twin required cerebral spinal fluid shunting. Neither child had a CSF leak or a CSF infection. At 6 months follow-up, both boys are rapidly acquiring speech in both English and Arabic, motor function is improving, and both are progressing toward independent ambulation.

This work concerns the effect of low frequency electromagnetic fields (ELF) on biochemical properties of human oral keratinocytes (HOK). Cells exposed to a 2 mT, 50 Hz, magnetic field, showed by scanning electron microscopy (SEM) modification in shape and morphology; these modifications were also associated with different actin distribution, revealed by phalloidin fluorescence analysis. Moreover, exposed cells had a smaller clonogenic capacity, and decreased cellular growth. Indirect immunofluorescence with fluorescent antibodies against involucrin and beta-catenin, both differentiation and adhesion markers, revealed an increase in involucrin and beta-catenin expression. The advance in differentiation was confirmed by a decrease of expression of epidermal growth factor (EGF) receptor in exposed cells, supporting the idea that exposure to electromagnetic field carries keratinocytes to higher differentiation level. These observations support the hypothesis that 50 Hz electromagnetic fields may modify cell morphology and interfere in differentiation and cellular adhesion of normal keratinocytes., (Copyright 2004 Wiley-Liss, Inc.)

Purpose: Transurethral resection, chemotherapy and radiation with salvage cystectomy may be used as alternatives to immediate radical cystectomy in the management of invasive bladder cancer. Concern exists about the function of the retained bladder after such therapy., Materials and Methods: Of 221 patients with clinical T2-4a bladder cancer treated at Massachusetts General Hospital from 1986 to 2000 with trimodality therapy, 71 were alive with native bladders and disease-free in 2001. These patients were asked to undergo a urodynamic study and to complete a quality of life questionnaire. A total of 69% participated in some component of this study with a median time from trimodality therapy of 6.3 years (range 1.6 to 14.9)., Results: Of 32 patients 24 had normally functioning bladders by urodynamic study. Decreased bladder compliance was seen in 7. Bladder hypersensitivity, involuntary detrusor contractions and incontinence were present in 2 women. The questionnaire showed that flow symptoms occurred in 6%, urgency in 15% and control problems in 19%. Of all women 11% wore pads. Distress from urinary symptoms was half as common as prevalence. Bowel symptoms occurred in 22% with 14% recording any level of distress. The majority of men retained sexual function. Global health related quality of life was high., Conclusions: The majority of patients treated with trimodality therapy retain good bladder function. A fifth have evidence of bowel dysfunction.

Background: We undertook this study to characterize those patients who required reoperations for Chiari malformation and to determine whether modifications in surgical technique at the initial procedure might have obviated the need for repeat surgery., Methods: We reviewed the hospital records, imaging studies, operative reports, and follow-up data of those patients who were undergoing a second operation as part of a consecutive series of Chiari decompressions carried out by one neurosurgeon over a 14-year period. We wished to determine whether type of Chiari malformation, age at initial surgery, the presence of associated bony anomalies, or initial operative technique contributed to the need for reoperation., Results: Twenty-two (17%) of the surgical procedures represented reoperations (16 of 100 Chiari I and 6 of 33 Chiari II decompressions). Of the patients in the series who were operated on at age 5 years or younger, 7 (16%) were reoperations (5 of 33 Chiari I and 2 of 10 Chiari II decompressions); 15 patients (17%) of those older than 5 years at surgery were reoperations (11 of 67 Chiari I and 4 of 23 Chiari II decompressions). 8 of the 16 patients who underwent reoperations for Chiari I malformation and 4 of the 6 patients who underwent reoperations for Chiari II malformation had their initial decompression surgery at age 5 years or younger. Reoperation was required because of failure to treat adequately an associated syrinx (n=11), because of persisting neurological symptoms or headache (n=9), or because of a possible faulty fourth ventricular stent placement (n=2). 5 of 9 patients in the operative series with Chiari malformations associated with craniosynostosis represented reoperations (55%), and all 3 of the patients whose syrinx persisted after reoperation had craniosynostosis syndromes., Conclusions: Approximately 17% of the patients with Chiari I and Chiari II malformations in this operative series were undergoing a second operation. Factors in this series which were associated with reoperation included a young age at initial surgery, the presence of complex bony anatomy at the foramen magnum, syndromic craniosynostosis, and failure of the surgeon at the initial operation either to assess patency of the foramen of Magendie or correctly place a fourth ventricular stent., (Copyright 2003 S. Karger AG, Basel)

Florid cemento-osseous dysplasia is an extensive form of periapical cemental dysplasia, which usually involves 1 to 4 posterior areas of the maxilla and mandible. The affected area undergoes changes from normal vascular bone into an avascular cementum-like lesion. The lesion is usually benign; however, treatment of a secondary infection of this lesion can be difficult and complicated. This clinical report describes a rare but aggressive secondary infection of this type, which was successfully treated by a combination of complex surgical and prosthodontic procedures, including dental implant therapy.

Objectives: To evaluate the role of short-term steroids after prostate brachytherapy to reduce oedema and thus the risk of urinary retention associated with brachytherapy, as this can require surgical intervention and may even result in incontinence., Patients and Methods: A retrospective review was conducted on 400 consecutive patients with early-stage prostate cancer who underwent ultrasonography-guided transperineal brachytherapy. Androgen deprivation was given to 146 patients for 3 months before the implant and 280 received a 2-week course of dexamethasone (4 mg twice daily for 1 week then 2 mg twice daily). Forty-five patients developed acute urinary retention at a median of 12 days after implantation. Univariate and multivariate analyses were used to evaluate the potential risk factors for urinary retention., Results: Acute urinary retention developed in 11.1% of the patients and the risk was predicted by increasing prostate volume at the time of diagnosis. This risk was higher (18.8%) for men receiving no dexamethasone and lower (8.2%) for those who did. In the multivariate analysis the volume at diagnosis and the use of dexamethasone remained significant. The use of steroids counterbalanced the effect of increasing prostate volume on the incidence of retention. The risk of retention was higher in those men receiving androgen deprivation to shrink their prostates than in those whose prostates were of suitable size for implantation at the time of diagnosis., Conclusion: Reducing prostate volume by androgen deprivation before brachytherapy may be less important in preventing brachytherapy-related urinary retention than the use of corticosteroids to reduce oedema afterward.

Purpose: This report of a clinical patient series indicates the relative safety and illustrates the procedures involved in the extraction of remaining teeth followed by immediate implant placement and loading with a simple acrylic resin fixed denture., Materials and Methods: Ten consecutive patients who selected tooth extraction and implant-supported fixed denture rehabilitation of the mandible were treated using a 1-visit approach for extraction, implant placement, and restoration. Healthy individuals (10 women) were treated under local anesthesia. Fifty-four implants were placed in 10 patients. Five or 6 Astra Tech implants (11 or 13 mm long) were placed into the edentulous parasymphyseal region of the mandible. Four to 6 implants (48 of 54) were immediately loaded by the fabrication of a simple acrylic resin fixed denture. The criterion for loading was clinical judgment of primary stability, ie, the absence of axial or lateral mobility with physical resistance to rotation. Patients were recalled at 1, 3, and 12 weeks. At 12 weeks, impressions were made for the fabrication of a screw-retained fixed denture. The fixed dentures were completed using conventional fabrication and prosthetic techniques., Results: After a period of 6 to 18 months, all 54 implants had survived and were considered 100% successful by independent testing of mobility and radiographic evidence of osseointegration. There were no surgical complications. Fracture and debonding of the acrylic resin provisional denture occurred for 1 patient during the first 12 weeks of treatment., Discussion: Advantages to extraction with simultaneous replacement include the maintenance of vertical dimension, elimination of reline procedures and interim denture therapy, and potential improvement of soft tissue healing., Conclusion: This therapeutic approach simplifies patient care without apparent additional risk.

The ability to perform a 'selective' dorsal rhizotomy has been challenged. EMG responses are inconsistent and often do not represent reflex responses. We perform nonselective partial dorsal rhizotomy (NSPDR) when reflex response is not evident. Ten children undergoing primarily NSPDR were evaluated preoperatively and postoperatively with the Modified Ashworth Scale, gait lab analyses gross motor function measure and the NSPDR was performed by nonselectively sectioning 50-75% of the dorsal roots not demonstrating a reflex response. Standard selective rhizotomy was performed in the remainder. Only 17 of 106 (16%) dorsal roots demonstrated reflex responses. The results reported in this study demonstrate a benefit to patients undergoing primarily NSPDR which is similar to that reported for patients in whom a selective procedure was intended., (Copyright 2000 S. Karger AG, Basel)

Background: In recent years the "tension-free" techniques have been progressively replacing conventional hernioplasty by Bassini and Shouldice. Personal experience in the application of various techniques using a prosthesis to make the back wall of the inguinal canal stronger is described., Methods: From January 1995 to February 1996, 119 non-selected patients were examined; they were operated by Trabucco's (100 cases), Lichtenstein's (16 cases), Gilbert's (13 cases) and Rives's (1 case) techniques, using polypropylene prostheses. Patients were followed for ten months (range 4-18) after surgery with Day-hospital checks at 1 month, 4 months, 1 year and 18 months., Results: Mortality was not observed. Morbility presented in 12 cases: 2 suppurating wounds, 3 seromas, 2 hematomas, 2 temporary neuralgias of the genito-femoral nerve and 2 scrotal edemas. There was a recurrence (0.8%)., Conclusions: The cases presented confirm the validity of the "tension-free" techniques, both for reduced incidence of complications and recurrences, and for a better compliance of the patient, compared with conventional techniques.

Background: To demonstrate the injury patterns of Alpine skiing and snowboarding in a northeastern state and evaluate potential risk factors., Methods: The medical records of a single pediatric and adult Level I trauma center were evaluated from January 1, 1990, through December 31, 1995. All admissions with injuries caused by Alpine skiing or snowboarding were reviewed. Those patients arriving from two local ski resorts, all of whose injuries are referred to the institution for care, were separated out for consideration. Age, sex, type of injury, date of injury, Injury Severity Score, operations performed, and outcome (including mortality) were evaluated. In addition, resort utilization for the study period was obtained from the two resorts included in the evaluation. Mortality data was obtained from the Vermont office of the Chief Medical Examiner for the same time period., Results: For the 6-year period of the study approximately 2,978,000 skier and snowboarder days were recorded at the study sites. Approximately 447,000 of those days were attributed to snowboarders (15%). In all, 279 patients were admitted for injuries (0.01%), 238 were related to Alpine skiing (incidence 0.01%) and 40 to snowboarding (incidence 0.01%). Snowboarders were statistically younger (20 years; range, 4-44 years) than skiers (29 years; range, 6-70 years) (p < 0.001) and had a significantly lower Injury Severity Score (15 in snowboarders vs. 27 in skiers, p < 0.03). Two female patients were injured snowboarding and 68 female patients were injured skiing. Eight percent of injured snowboarders and 16% of injured skiers sustained multiple injuries (p < 0.01). Injury patterns were significantly different. Upper extremity injuries were almost exclusively found in snowboarders (24% vs. 7%, p < 0.003), whereas cruciate ligament injuries occurred far more commonly in skiers (45% vs. 4%, p < 0.001 Lower extremity injuries in general were more common in skiers (78% vs. 38%, p < 0.001). Central nervous system injuries, including head and spine, were evenly distributed over the two groups, although the snowboarders with central nervous system injuries were younger. In addition, splenic injuries were more common in snowboarders (13% vs. 2%, p < 0.01). Snowboarding accidents were far more common in December, March, and April than other months. Fifty-one patients sustained abdominal or chest injuries and only two of these required operative intervention (two splenectomies). Other operative interventions were limited to extremity injuries, injuries of the spine, or placement of an intracranial pressure monitor. There were no fatalities recorded in this population, although over the 6.5 years, there were 25 deaths related to alpine skiing and one to snowboarding in the State (incidence 0.0000009 skier days). Victims tended to be male: 96% of the skiers and the one snowboarder. The predominant cause of death was blunt head trauma followed by blunt chest trauma. Helmets were not worn by those sustaining head injuries or fatalities. Spine injuries were recorded only in extremely young snowboarders and skiers out of control., Conclusion: Snowboarders and Alpine skiers are equally prone to injury. Snowboarding accidents are typically less severe and show significantly different injury patterns than skiing accidents. Abdominal and chest injuries in this population are generally amenable to nonoperative management. Prevention programs are best targeted at safe skiing and snowboarding practices, not skiing or snowboarding in poor conditions, use of helmets for skiers, and restraint of snowboard use in very young children.

The authors present their experience (136 cases) in the treatment of cholelithiasis with coelioscopic cholecystecomy. After a comparison of this modern technique with the traditional laparotomic approach, they underline the several advantages of coelioscopy (short hospitalization and early return to patient's work, reduced post-operative abdominal pain, avoidance of laparocele, better aesthetic results). Then the authors describe the present treatment of combined cholecysto-choledochic lithiasis with the help fo ERCP (their hope is for further improvement in surgical instruments to allow a single laparoscopic solutions.

The authors describe three cases of gastric leiomyosarcoma that required surgical treatment in emergency. Myogenic gastric tumors are extremely rare (1-3% of primitive gastric neoplasias) and little is known about their biological evolution, even if they seem to have scarce power of spreading and of local invasion. Echoendoscopy appears to be the best screening method for the evaluation of staging and DT (doubling time). In the authors' opinion, when neoplasms have a diameter less than 5 cm, subtotal or total gastrectomies don't offer better results in the follow-up than simple minimal excision of the gastric tumor.

The authors describe a case of acute abdomen operated in emergency for obstruction in a patient with eosinophilic gastritis. This is very unusual pathology characterized by eosinophilic infiltration of the gastric antral wall combined with peripheric eosinophilia. This particular case was operated for a small bowel obstruction but in those rare cases, when we can reach a diagnosis with endoscopic biopsy, a prudential attitude becomes inevitable as this pathology is very responsive to medical treatment with corticosteroids.

The covalent fixation of benzenehexacarboxylate (BHC) onto dextran was carried out according to several reaction schemes. The polyanionic polymers thus synthesized were capable of decreasing the oxygen affinity of hemoglobin by specifically interacting with the 2,3-diphosphoglycerate (2,3-DPG) binding site of the protein. The intensity of this effect was correlated to both the chemical structure of the polyanionic polymers and the BHC content in polymer. The polyanionic polymer, containing 0.035 mol BHC/g and presenting no cross-linking between its polymer chains, possessed the best effector properties. These properties were used to direct the covalent fixation of the dextran-benzenehexacarboxylate onto the phosphate binding site of the protein. The resulting hemoglobin was mainly substituted at the same time by one or more linked BHC onto both alpha beta dimers in the vicinity of the 2,3-DPG site. Thus, the modification of hemoglobin led to an increase in the hydrodynamic volume of each dimer sufficient to limit the diffusion of the conjugates through the kidney membrane, even if the conjugates had dissociated into alpha beta dimers. Compared to that of free hemoglobin, the oxygen affinity of the conjugates was significantly decreased. This type of covalent conjugate exhibited general properties quite suitable for use as blood substitutes.

The authors describe their experience in the surgical treatment of splenic lesions, mostly traumatic. In recent years a resolutely conservative attitude has been turned to splenic salvage, thanks to late findings on its immunological and haematological functions. Against 59 splenectomies for III-V degree lesions, the authors report a case of splenic trauma (II degree) without surgical treatment, monitored with clinical, haematological and instrumental (echography) test.

The authors describe an acute intestinal occlusion due to a rare case of strangulated intra-abdominal hernia of the retrocaecal peritoneal recess. They underline the rarity of this pathology which is often treated in emergency without any possibility of preoperative diagnosis. Therefore, in order to carry out surgical therapy with good results, a correct knowledge of the anatomical features of these hernias is necessary.

Background: Imaging trials using arteriography have been shown to be effective alternatives to clinical end point studies of atherosclerotic vascular disease progression and the effect of therapy on it. However, lack of consensus on what end point measures constitute meaningful change presents a problem for quantitative coronary arteriographic (QCA) approaches. Furthermore, standardized approaches to QCA studies have yet to be established. To address these issues, two different arteriographic approaches were compared in a clinical trial, and the degree of concordance between disease change measured by these two approaches and clinical outcomes was assessed., Methods and Results: In the Familial Atherosclerosis Treatment Study (FATS) of three different lipid-lowering strategies in 120 patients, disease progression/regression was assessed by two arteriographic approaches: QCA and a semiquantitative visual approach (SQ-VIS). Lesions classified with SQ-VIS as "not," "possibly," or "definitely" changed were measured by QCA to change by 10% stenosis in 0.3%, 11%, and 81% of cases, respectively. The "best" measured value for distinguishing definite from no change was identified as 9.3% stenosis by logistic regression analysis. The primary outcome analysis of the FATS trial, using a continuous variable estimate of percent stenosis change, gave almost the same favorable result whether by QCA or SQ-VIS., Conclusions: The excellent agreement between these two fundamentally different methods of disease change assessment and the concordance between disease change and clinical outcomes greatly strengthens confidence both in these measurement techniques and in the overall findings of the study. These observations have important implications for the design of clinical trials with arteriographic end points.

Lipid-lowering therapy, as assessed by angiography, clearly benefits the arterial disease process. For example, among intensively treated patients in FATS the frequency of definite progression per lesion at risk was reduced by 75% among mild and moderate lesions, which form the great preponderance of the lesion population. Regression frequency per lesion was more than doubled by intensive therapy in mild and moderate subgroups and quadrupled in the subgroup with severe lesions. Clinical events were reduced by 73%. This was clearly due to a 15-fold reduction in the likelihood that a mildly or moderately diseased arterial segment would undergo abrupt and substantial progression to a severe lesion at the time of the clinical event. It has been shown that the process of plaque fissuring, leading to plaque disruption, thrombosis, and clinical coronary events, is predicted by the size of the plaque core lipid pool and the abundance of lipid-laden macrophages in its fibrous cap. Experimentally, lipid lowering therapy decreases the number of lipid-laden intimal macrophages and more slowly depletes core cholesteryl ester deposits. Thus the composite of new and previously published data presented here supports the idea that lipid-lowering therapy selectively lipid-depletes (causes regression of) those fatty lesions containing a large lipid core and abundant intimal foam cells. By doing so, these lesions, which are most vulnerable to fissuring, are rendered much more stable and the clinical event rate is accordingly decreased.

Cosmetics can produce severe distortion of the orbital contents in MR imaging. This distortion, typical of compounds that exhibit a permanent magnetic moment, results from iron oxide in the pigments used to produce dark shades of makeup. In general, the artifact created by cosmetics does not interfere with interpreting routine head scans. However, if the orbital contents are the subject of clinical concern, the images may then be rendered nondiagnostic. The artifact created by the makeup is propagated along the frequency-encoding axis of the images.

Interactions of dextran sulfate with amino groups of oxy- and deoxyhemoglobin were followed by both potentiometric measurements between pH 6 and 7.3 and oxygen-binding studies. The uptake of protons observed upon addition of dextran sulfate to hemoglobin shows that the interaction with the deoxy form is strong and that the main site is probably located in the phosphate-binding beta-cavity, whereas the interaction with the oxy form is more diffuse, probably with a great number of relatively weak binding sites. The influence of dextran sulfate on the oxygen dissociation curve of hemoglobin confirms these findings, as the effect of the polymer is to lower hemoglobin affinity for oxygen to a great extent, which proves that it stabilizes the deoxy form more strongly than the oxy one.

One hundred sixteen magnetic resonance (MR) imaging studies from 105 pediatric patients with a variety of cerebral abnormalities were reviewed to determine the diagnostic efficacy of MR in the pediatric population. All subjects tolerated the MR procedure well, although sedation was necessary for younger children. Compared with CT, MR proved to be advantageous in detection and characterization of the pathology in 23 of 105 patients, especially when the abnormality was located along the base of the brain and midline, or when it involved primarily the white matter. Intracranial calcification was the one abnormality not detected with MR although dense calcifications could be seen as areas of low signal intensity. Some characteristics of various pathological entities were compared in an attempt to differentiate among abnormalities in the same anatomical location: craniopharyngioma from optic chiasm and hypothalamic glioma, cystic glioma from arachnoid cyst, and chronic subdural hematoma from subdural hygroma. The lack of ionizing radiation in MR is of particular interest in pediatric neuroradiology since radiation is of special concern in the young age group.

The process of creating MR images frequently gives rise to artifacts in the final display. Many artifacts may be corrected or ameliorated through an understanding of their cause. This requires familiarity with scanner design; theory of operation; and image acquisition, generation, and display. Some artifacts are obvious, totally degrading the image; others are regional, leaving much of the scan undisturbed. In some cases, the degradation is permanent; in others, the data can be reprocessed or manipulated to yield artifact-free images. Some artifacts are overt and easily identified. Others, such as those caused by phase-shift or gradient-strength effects, are subtle and require careful observation for detection.