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71.

Background

Hemoglobin sickle cell disease is one of the most frequent hemoglobinopathies. Surprisingly, few studies have been dedicated to this disease, currently considered to be a mild variant of homozygous sickle cell disease. The aim of this study was to update our knowledge about hemoglobin sickle cell disease.

Design and Methods

The study involved a single center series of 179 patients. Clinical and biological data were collected with special attention to the assessment of pulmonary arterial hypertension and nephropathy.

Results

Hemoglobin sickle cell diagnosis was delayed and performed in adulthood in 29% of cases. Prevalence of hospitalized painful vasoocclusive crisis, acute chest syndrome and priapism was 36%, 20% and 20%, respectively. The most common chronic organ complications were retinopathy and sensorineural otological disorders in 70% and 29% of cases. Indeed, prevalence of complications reported in homozygous sickle cell disease, such as nephropathy, suspicion of pulmonary hypertension, strokes and leg ulcers was rather low (13%, 4% and 1%, respectively). Phlebotomy performed in 36% of this population (baseline hemoglobin 11.5 g/dL) prevented recurrence of acute events in 71% of cases.

Conclusions

Our data suggest that hemoglobin sickle cell disease should not be considered as a mild form of sickle cell anemia but as a separate disease with a special emphasis on viscosity-associated otological and ophthalmological disorders, and with a low prevalence of vasculopathy (strokes, pulmonary hypertension, ulcers and nephropathy). Phlebotomy was useful in reducing acute events and a wider use of this procedure should be further investigated.  相似文献   
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Purpose

Non-fusion treatment for adolescent idiopathic scoliosis generates interest due to the potential for growth preservation and mobility. Using an established porcine scoliotic model, this study aims to evaluate the global alignment and the morphology of the spine with and without application of a non-fusion corrective tether.

Methods

At 12 weeks of age, 21 immature Yorkshire pigs had an induction of scoliosis. Once a 50° Cobb angle was obtained; animals were placed into one of the following groups: a scoliosis model group (SM, n = 11) where animals were euthanized, tether release group (TR, n = 5) where the inducing tether was removed, and an anterior correction group (AC, n = 5) where the inducing tether was removed and non-fusion corrective tether was applied. TR and AC were observed for a further 20 weeks and then euthanized. Post-mortem CT scans were used to create 3D spinal reconstructions to obtain global and morphologic parameters.

Results

Maximal Cobb angle of the scoliotic deformity was significantly lower for AC (27.9° ± 12.0°) than for the two other groups (TR 52.7° ± 10.0°, SM 48.3° ± 7.6°). AC experienced an increase in kyphosis (24.2° ± 15.9°) compared to TR (7.1° ± 6.4°). Correction in the axial plane was also observed in AC versus TR. Correction of vertebral wedging was found for AC compared to SM and TR in the three apical vertebrae.

Conclusions

3D realignment of scoliotic curves was observed with application of the corrective tether. The correction was the product of both mechanical action and growth modulation. These findings are encouraging for future development of a non-fusion device for the treatment of immature scoliotic curves.  相似文献   
75.

Background

Whereas palliative chemotherapy offers a median survival of approximately 10 months in advanced gastric and junctional adenocarcinoma (AGJA), the survival impact of primary tumor resection is controversial. Our purpose was to identify which AGJA patients benefit from palliative resection.

Methods

In 3,202 AGJA patients scheduled for surgery in 21 French centers between 1997 and 2010, prognostic factors were identified in palliative group and the impact of each combination of these factors on survival was studied.

Results

Surgery was defined as palliative due to solid organ metastasis (5.6 %), localized (4.6 %) or diffuse (2.3 %) peritoneal carcinomatosis (PC), or incomplete tumoral resection (12.8 %). Median survival of AGJA patients resected with a palliative intent (n = 677) was longer than in nonresected patients (n = 532; 11.9 vs. 8.5 months, P < 0.001). Multivariable analyses identified ASA score III-IV (P < 0.001) as a predictor of postoperative mortality and solid organ metastasis (P = 0.009), localized PC (P = 0.004), diffuse PC (P = 0.046), and signet ring cell histology (SRC; P = 0.02) as predictors of survival. Only ASA I–II patients with incomplete resection without metastasis or PC, one site solid organ metastasis without PC, or localized PC without SRC had a survival benefit after palliative surgery with median survivals from 12.0 to 18.3 months. Nonresected ASA I–II patients with same risk factors had median survivals from 3.5 to 8.8 months (P < 0.05 for each).

Conclusions

In AGJA, patient and tumor-related factors should be used to select candidates for palliative surgery in association with chemotherapy.  相似文献   
76.
The aim of the present study was to investigate temporal abilities in children treated by surgery for a malignant tumor in the cerebellum. Children with a diagnosed medulloblastoma and age-paired control children were given a temporal discrimination task (bisection task) and a temporal reproduction task with two duration ranges, one shorter than 1 s and the other longer than 4 s. The motor and cognitive capacities of these children were also assessed by a battery of age-adapted neuropsychological tests. The results did not show any significant difference in performance between the children with or without cerebellar lesions in the temporal discrimination task. It was only in the temporal reproduction task that the children with cerebellar lesions reproduced longer and more variable durations than the other children, but only for the short stimulus durations (≤1 s). In addition, a hierarchical regression analysis revealed that the best predictor of variance in temporal performance was a significantly lower processing speed in children with cerebellar lesions in comparison to their controls. These results indicated that the major cause of deficits in temporal judgments in children with cerebellar lesions was due to their inability to reproduce accurately short temporal intervals in association with low processing speed, rather than to a specific deficit in the perception of time.  相似文献   
77.
The present paper aims to analyze trends over time in prevalence of cerebral palsy of post-neonatal origin, to investigate whether changes are similar according to severity and to describe the disability profile by etiology. Post-neonatal cases, birth years 1976 to 1998, were identified from the Surveillance of Cerebral Palsy in Europe collaboration (19 population-based registries). A recognized causal event occurring between 28 days and 24 months of age was considered to define the cases. Trends in prevalence were explored using graphical methods (Lowess and Cusum control chart) and modeled with negative binomial regressions. Over the study period, 404 cases were identified as post-neonatal cases (5.5% of the total). Mean prevalence rate was 1.20 per 10,000 live births (95% CI [1.08–1.31]). A significant downward trend was observed (p = 0.001), with an accentuated decrease in the 1990s. The prevalence of severe cases which account for around one third of the total also significantly decreased over time (p < 0.001). In 46% of cases, an infectious aetiology was reported; the corresponding prevalence significantly decreased since 1989. No significant decrease was observed for the rate of cases due to a vascular episode or of traumatic origin. Our results emphasize the need of large population-based surveillance systems to reliably monitor trends in prevalence in rare subgroups of children like those with acquired cerebral palsy. The decrease of the overall prevalence as well as those of the most severe cases may be partly due to public health actions targeted to prevent such events.  相似文献   
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The objective of this article is to review various unsightly periodontal defects and the treatments that have previously been used to eliminate them in order to establish guidelines for future therapy. The inter-relationship between orthodontic and periodontal disciplines is well established and needs no defense here. Periodontal tissues change throughout life and the same is true for the smile. The periodontium is an essential component of the appearance of the face as well as the lips. These are dynamic esthetic criteria while the gingiva and the static character of the dentition also contribute to the character of an individual's smile. In order to conduct orthodontic therapy most effectively it is essential that orthodontists and periodontists utilize a coordinated approach. From the beginning, they must establish an etiological diagnosis of any esthetic defects that will insure that their joint therapy is conducted appropriately and at the proper moment.  相似文献   
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