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1.
The present study was aimed at defining the standard conditions for predictive chemosensitivity testing of human leukaemias. The in vitro cytotoxic potential of 11 anticancer drugs against L1210 murine leukaemia was comparatively determined 3 and 48 h after in vitro exposure of leukaemia cells to these agents. In preliminary testing, drug-induced damage was estimated in terms of percent inhibition of: tumour cell proliferation, by microscopic determination of viable cell numbers; and DNA synthesis, by measuring the extent of incorporation of the labelled nucleoside 125IUdR. Since the two tests appeared to yield comparable results, all subsequent experiments on the various murine tumours were performed using the radiolabel incorporation technique. The results obtained pointed out that this metabolic assay performed 48 hours after drug exposure appears to be capable of predicting both "spontaneous" and "induced" in vivo resistance of murine leukaemias.  相似文献   
2.
To evaluate the morphologic basis of the different outcomes of toluene diisocyanate (TDI) asthma after quitting occupational exposure, we examined ten patients with TDI asthma who showed, at diagnosis, a positive TDI challenge test and nonspecific bronchial hyperresponsiveness (NSBH) to methacholine. After diagnosis, all patients ceased work and a 4- to 40-month follow-up was obtained with three to eight determinations of the cumulative dose producing a 15 percent fall in FEV1 (PD15FEV1) methacholine in each patient. Bronchoalveolar lavage (BAL) and biopsy of bronchial muscosa were performed 3 to 39 months after cessation of work, in the absence of acute exacerbations of the disease. Total cell count in BAL fluid was moderately increased in four of ten patients, eosinophils were increased in five of ten patients, and neutrophils were increased in eight of ten patients. Mucosal biopsy specimens of main or lobar bronchi were available in eight of ten patients; epithelial damage and thickening of basement membrane was observed in almost all patients, as well as a mild-to-moderate inflammatory reaction in the submucosa, mainly represented by lymphocytes, eosinophils, and neutrophils. No relationship was observed between the cellularity of BAL and the degree of NSBH at the time of BAL; mean values of total cells and differential count were not different between patients with presence or absence of the different histologic findings. Mucosal biopsy and BAL were performed also in four subjects exposed to dusts without respiratory symptoms or NSBH; similar findings were obtained except for the absence of eosinophils in BAL and a lesser degree of basement membrane thickening and inflammatory reaction in the submucosa. The study of the changes in NSBH after quitting exposure showed that five of ten patients had a significant improvement in NSBH to methacholine, as evaluated by a positive significant linear regression between months of work cessation and PD15FEV1 methacholine; only one of these five patients had an increased number of eosinophils in BAL fluid. By contrast, four of the five patients with persistent NSBH after quitting exposure had an increased number of eosinophils in BAL. We suggest that persistent NSBH in TDI asthma after cessation of work may be related to an inflammatory reaction in which eosinophil infiltration seems to be a major determinant.  相似文献   
3.
Recessive nebulin (NEB) mutations are a common cause of nemaline myopathy (NM), typically characterized by generalized weakness of early-onset and nemaline rods on muscle biopsy. Exceptional adult cases with additional cores and an isolated distal weakness have been reported. The large NEB gene with 183 exons has been an obstacle for the genetic work-up. Here we report a childhood-onset case with distal weakness and a core-rod myopathy, associated with recessive NEB mutations identified by next generation sequencing (NGS). This 6-year-old boy presented with a history of gross-motor difficulties following a normal early development. He had distal leg weakness with bilateral foot drop, as well as axial muscle weakness, scoliosis and spinal rigidity; additionally he required nocturnal respiratory support. Muscle magnetic resonance (MR) imaging showed distal involvement in the medial and anterior compartment of the lower leg. A muscle biopsy featured both rods and cores. Initial targeted testing identified a heterozygous Nebulin exon 55 deletion. Further analysis using NGS revealed a frameshifting 4 bp duplication, c.24372_24375dup (P.Val8126fs), on the opposite allele. This case illustrates that NEB mutations can cause childhood onset distal NM, with additional cores on muscle biopsy and proves the diagnostic utility of NGS for myopathies, particularly when large genes are implicated.  相似文献   
4.
Metabolomics is the analysis of the concentration profiles of low molecular weight compounds present in biological fluids. Metabolites are nonpeptide molecules representing the end products of cellular activity. Therefore, changes in metabolite concentrations reveal the range of biochemical effects induced by a disease or its therapeutic intervention. Metabolomics has recently become feasible with the accessibility of new technologies, including mass spectrometry and high-resolution proton nuclear magnetic resonance, and has already been applied to several disorders. Indeed, it has the advantage of being a nontargeted approach for identifying potential biomarkers, which means that it does not require a preliminary knowledge of the substances to be studied. In this review, we summarize the main studies in which metabolomic approach was used in some allergic (asthma, atopic dermatitis) and rheumatic diseases (rheumatoid arthritis, systemic lupus erythematosus) to explore the feasibility of this technique as a novel diagnostic tool in these complex disorders.  相似文献   
5.
Three prime repair exonuclease 1 (TREX1) degrades excess HIV-1 DNA, thereby preventing recognition by innate immunity receptors and type I interferon responses. Analyses performed in two HIV-exposed seronegative (HESN) cohorts did not show any differences in TREX1 sequence, single nucleotide polymorphisms frequency, or expression in HESN compared to controls, suggesting that, despite its central role in the HIV-1 infection process, genetic diversity at TREX1 is not a major determinant of susceptibility to infection in humans.  相似文献   
6.
This study aimed at exploring the relationship between severe neuromotor and/or sensory disability in very preterm infants assessed at 2 years corrected age and their mothers’ psychological health. Data on 581 Italian singletons born at 22–31 weeks of gestation in five Italian regions and their mothers were analyzed. Maternal psychological distress was measured through the General Health Questionnaire short version (GHQ-12). The prevalence of any maternal distress (GHQ scores  2) and of clinical distress (scores  5) were 31.3% and 8.1% respectively. At multivariable analysis, we found a statistically significant association between child's disability and mothers’ GHQ scoring ≥5 (OR 3.45, 95% CI 1.07–11.15). Also lower maternal education appeared to increase the likelihood of psychological distress (OR 1.38, 95% CI 1.14–1.66). The impact of child disability was weaker in women who had experienced additional stressful life events since delivery, pointing to the existence of a “ceiling” effect. Maternal psychological assessment and support should be included in follow-up programs targeting very preterm infants.  相似文献   
7.
Neurological Sciences - The novel human coronavirus (SARS-CoV-2) shows neurotropism and systemically affects the central nervous system (CNS). Cognitive deficits have been indeed reported as both...  相似文献   
8.
9.

Summary

There is still no clarity on the etiology and epidemiology of atypical femoral fractures. The purpose is to show, after a radiological review, that the incidence of atypical fractures is higher than that reported in the literature when compared to “typical” fractures that occurred in the same anatomical site.

Introduction

At present, it is difficult to define the true incidence of atypical fractures associated with bisphosphonate. Our purpose is to show that the incidence of atypical fractures is higher than that reported in the literature when compared to “typical” fractures that occurred in the same anatomical site.

Methods

The authors analyzed 319 femoral fracture Rxs of patients over 60 who have had access to the PS of Clinical Orthopaedics and Traumatology II of the University of Pisa from January 2011 to February 2013. The atypical fractures have been investigated from clinical point of view, biohumoral exams, densitometry and contralateral femur X-rays, and in one case using SPECT-Tc.

Results

The total number of femoral fractures was 319. The medial femur fractures were 60 (46 females and 14 males), and the lateral ones were 316 (237 females and 79 males). Subtrochanteric and diaphyseal fractures were 40 (29 females and 11 males). Among these cases, two atypical fracture cases were related to female patients, one was 79 years old and the other was 77.

Conclusions

The most recent literature reports that the incidence of atypical fractures is 0.6 %. However, taking into consideration only the fracture locations suitable for the identification of atypical fractures, the percentage rises to 5 %. To date, there is still no clarity on the exact etiology of fractures even if it seems to be related to a bone mineral component alteration.  相似文献   
10.
BACKGROUND Pancreatic acinar cell carcinoma (PACC) is a rare type of malignant pancreatic cancer that represents approximately 1%of all pancreatic neoplasms.Due to its very low incidence,only a few retrospective studies are available.Although surgery is the first choice for treatment,most patients experience recurrence(mainly in the liver) and there are no clear recommendations for patients with advanced disease.CASE SUMMARY We report two patients with PACC treated with sturgery who experienced tumour recurrence in the liver.Patient 1 carried a germline mutation in the APC gene.Both patients were treated with gemcitabine plus oxaliplatin and gemcitabine plus capecitabine as first-and second-line therapies,respectively.After a favoturable response to chemotherapy,the patients underwent radiofrequency ablation of the remaining liver metastases.For patient 1,we documented a relapse in the liver after a disease-free period of 9 mo,and treatment with gemcitabine plus capecitabine was restarted.The patient achieved a complete response,and he remains alive without evidence of disease recurrence after six years.After radiofrequency ablation,patient 2 experienced disease-free survival for 21 mo,when peritoneal relapse was diagnosed and treated with chemotherapy.The patient achieved a stable disease state for nearly two years;nevertheless,further progressive disease was documented,and he died seven years after the first relapse.CONCLUSION PACC presents different biological behaviours than pancreatic adenocarcinoma.Multidisciplinary treatment involving local ablative therapies may be considered for PACC.  相似文献   
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