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101.
Cell adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1) play an important role in glioma invasion and angiogenesis. The aim of this study was to investigate whether specific genetic polymorphisms of ICAM-1 and PECAM-1 could be associated with glioma development and progression. Single-nucleotide polymorphism in codon 469 of ICAM-1 and codon 125 of PECAM-1 were examined in 158 patients with astrocytomas and 162 controls using polymerase chain reaction and restriction enzyme analysis. The distribution of PECAM-1 polymorphic genotypes in astrocytomas did not show any significant difference. However, a specific ICAM-1 genotype (G/G, corresponding to Lys469Glu) exhibited higher frequency in grade II astrocytomas compared to controls, grade III, and grade IV astrocytomas; suggesting that this polymorphism could be involved in the development of grade II astrocytomas.  相似文献   
102.
OBJECTIVE: Although endometrial polyps likely originate from reserve cells in the basal layer, the underlying biology is not fully understood. One protein that plays an important role in regulating epithelial proliferation and differentiation is the 63-kd membrane protein (p63), which is also a marker of basal and reserve cells in the female genital tract. Our objective was to determine whether p63 is expressed differently in postmenopausal endometrial polyps than in the adjacent endometrium. DESIGN: In this study, 36 specimens of endometrial polyps and 36 samples of the adjacent endometrium were obtained from postmenopausal women through hysteroscopic surgery performed in a tertiary-care university hospital. Immunohistochemistry was used to evaluate the expression of p63 in all samples. RESULTS: The majority of endometrial polyp samples (94.4%) presented nuclear immunostaining for p63, whereas only 5.6% of adjacent endometrium samples were positive for p63 (P < 0.0001). Distribution of p63 immunostaining in the endometrial polyp samples was homogeneous. CONCLUSIONS: Our results provide evidence that a basal cell immunophenotype is maintained in the endometrial polyps seen in postmenopausal women, suggesting that p63 plays a role in the pathogenesis of such polyps.  相似文献   
103.
We analyzed a collection of 60 Salmonella enterica 4,5,12:i:- phage type U302 multidrug-resistant monophasic variant strains, isolated in Spain between 2000 and 2007. Most strains showed resistance to ampicillin (A), chloramphenicol (C), sulfamethoxazole (Su), gentamicin (G), streptomycin (S), tetracycline (T), and co-trimoxazole (SxT) (an ACSuGSTSxT resistance pattern). Only one pulsed-field gel electrophoresis (PFGE) type was detected, with 19 subtypes (Simpson's index of diversity [SID]=0.89). Multiple-locus variable-number tandem-repeat analysis (MLVA) showed more variability, with 32 profiles (SID=0.97), but only showed diversity at the STTR5 and STTR6 loci. PCR and sequencing demonstrated all strains contained the same allantoin-glyoxylate pathway deletion. Four types of deletions were detected in the fljAB operon, all starting at the same position, at the STM2758 gene, and followed by an IS26 insertion. Furthermore, a representative set of strains of the four deletion types harbored plasmids with IS26. We propose that a Salmonella enterica serotype Typhimurium U302 multidrug-resistant (ACSuGSTSxT) strain, defective for the allantoin-glyoxylate pathway and containing IS26 at plasmid pU302L, could be the ancestor of the variant in Spain.  相似文献   
104.
Hippocampal volume is reduced in Alzheimer Disease (AD) and has been proposed as a possible surrogate biomarker to aid early diagnosis. Whilst automated methods to segment the hippocampus from magnetic resonance images are available, manual segmentation, in spite of being time-consuming and unsuitable for large samples, is still the standard. In order to study the validity of FreeSurfer's automated method, we compared hippocampal automated measures with manual tracing in a sample composed of healthy elderly (N = 41), Mild Cognitive Impairment (MCI) (N = 23), and AD (N = 25) subjects. Percent volume overlap, percent volume difference, correlations, and Bland–Altman plots were studied. Automated measures were slightly larger than hand tracing ones (mean difference 10%). Percent volume overlap showed good results, but was far from perfect (78%). Manual and automated volume correlations were approximately 0.84 and the Bland–Altman analysis showed acceptable interchangeability of methods. Within-group analysis demonstrated that patient samples obtained smaller values in validity indexes than controls. Globally, FreeSurfer's automated hippocampal volumetry showed adequate validity when compared to manual tracing, with a tendency to overestimation. Nevertheless, the greater difference between automated and manual segmentation in atrophic brains suggests that studies in AD based on this software could be more likely to produce false negatives.  相似文献   
105.

Summary

Background

Metastatic tumors account for less than 1% of all malignant tumors occurring in the oral cavity.

Case Report

The clinical case of a 94-year-old patient with a mandibular tumor is reported here. The patient had undergone bilateral mastectomy more than 25 years before. An immunohistochemical study found hormone receptors in signet ring cells, suggesting a diagnosis of breast cancer metastasis.

Conclusion

Immunohistochemical diagnosis and antineoplastic hormone therapy is the cornerstone in the management of this clinical case.Key Words: Mandible, Metastasis, Breast cancer, Signet ring cells  相似文献   
106.
BACKGROUND: There is little information about weight gain induced by antipsychotics at long-term. OBJECTIVE: To quantify the weight gain induced by first (haloperidol) and second generation antipsychotics (olanzapine and risperidone) in a cohort of drug-na?ve subjects after 1 year of treatment. METHODS: This is a prospective, randomized clinical trial, including a representative sample of first episode psychotic incident cases from a population area of 555.000 people. The main outcome measures were changes in body weight and body mass index at 3 months and at 12 months. Both a per protocol analysis and an intention to treat analysis were conducted. RESULTS: A total of 164 drug-na?ve patients were included. At 12 months 144 patients were evaluated. Of them, 66% completed the protocol and 34% needed treatment switch. We found statistically significant differences in weight gain at 3 months: 3.8 kg (+/-4.1) for haloperidol, 5.9 kg (+/-5.1) for risperidone and 8.4 kg (+/-5.0) for olanzapine (F=7.045; p=0.002). After 1 year the difference in weight gain had disappeared: 9.7 kg (+/-5.7) for haloperidol, 8.9 kg (+/-8.8) for risperidone and 10.9 kg (+/-7.2) for olanzapine (F=0.817; p=0.445). CONCLUSIONS: Drug-na?ve patients experience an extraordinary weight gain after 1 year of treatment with haloperidol, olanzapine or risperidone. The main difference among these treatments is the pattern of weight gain but not the final amount of weight gain.  相似文献   
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Cognitive deficits are core features of schizophrenia that are already evident at early phases of the illness. The study of specific relationships between cognition and brain structure might provide valuable clues about neural basis of schizophrenia and its phenomenology. The aim of this article was to review the most consistent findings of the studies exploring the relationships between cognitive deficits and brain anomalies in schizophrenia. Besides several important methodological shortcomings to bear in mind before drawing any consistent conclusion from the revised literature, we have attempted to systematically summarize these findings. Thus, this review has revealed that whole brain volume tends to positively correlate with a range of cognitive domains in healthy volunteers and female patients. An association between prefrontal morphological characteristics and general inability to control behaviour seems to be present in schizophrenia patients. Parahippocampal volume is related to semantic cognitive functions. Thalamic anomalies have been associated with executive deficits specifically in patients. Available evidence on the relationship between cognitive functions and cerebellar structure is still contradictory. Nonetheless, a larger cerebellum appears to be associated with higher IQ in controls and in female patients. Enlarged ventricles, including lateral and third ventricles, are associated with deficits in attention, executive and premorbid cognitive functioning in patients. Several of these reported findings seem to be counterintuitive according to neural basis of cognitive functioning drawn from animal, lesion, and functional imaging investigations. Therefore, there is still a great need for more methodologically stringent investigations that would help in the advance of our understanding of the cognition/brain structure relationships in schizophrenia.  相似文献   
110.
OBJECTIVE: Striatal dysfunction has been traditionally implicated in the pathophysiology of schizophrenia. The purpose of this study is to examine the relationship between caudate nucleus volumes and clinical and cognitive features of schizophrenic patients in an early phase of their illness. METHODS: Caudate nucleus volumes in previously untreated first episode patients with non-affective psychosis (N=76) and healthy comparison subjects (N=45) were measured. Caudate nucleus volume in the right and left hemispheres were automatically segmented and analyzed using BRAINS2. Analysis of covariance was used to control for intracranial volume. Severity of clinical symptoms was assessed using SAPS and SANS total scores. The relationship between cognitive dimensions, and caudate nucleus volume was evaluated. Finally, we examined the correlation between caudate volumes and the duration of untreated illness (DUI), duration of untreated psychosis (DUP) and duration of prodrome period (DPP). RESULTS: Right, left, and total caudate nucleus volumes did not differ significantly between patients and controls. Those patients with a longer DUP have smaller caudate nucleus. In addition, caudate nucleus volume was positively correlated with the severity of psychotic symptomatology. No significant associations were found between caudate nucleus volume and cognitive functioning. CONCLUSION: This group of first episode schizophrenia patients did not exhibit significant volumetric anomalies of the caudate nucleus. Despite this lack of volumetric abnormalities, a delay in receiving antipsychotic treatment and the severity of initial positive symptomatology were significantly associated with reduced caudate volume.  相似文献   
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