Extracellular metalloproteinase activity in <Emphasis Type="Italic">Phytomonas françai</Emphasis>

Extracellular proteolytic activities were detected in Phytomonas françai culture supernatant. A 67-kDa enzyme was purified by ammonium sulfate precipitation and gel filtration in a HPLC system. This proteinase was optimally active at 28 °C and pH 5.0; and the use of proteolytic inhibitors indicated that it belongs to the metalloproteinase class. This is the first report on the purification of an extracellular metalloproteinase from a Phytomonas species.     

Looking for ferns: optimization of digestion pretreatment in fluorescence in situ hybridization (FISH) technique on paraffin-embedded tissues.

Fluorescence in situ hybridization (FISH) is a useful cytogenetic technique for the detection of chromosome aberrations. However, applying this technique routinely on paraffin-embedded tissue is hampered by technical problems. The efficiency of hybridization is influenced by formalin fixation time, and this may vary considerably between specimens. We present a simple method for improving hybridization by microscopically monitoring the time of enzymatic digestion. To establish optimal digestion time, enzymatic digestion was stopped at 3-minute intervals for biopsies and 10-minute intervals for autopsies in 24 paraffin-embedded samples. At every stop, tissue morphology was examined under light microscopy to determine if observed changes could be correlated with subsequent FISH results. The appearance of fernlike formations was found to mark the optimal digestion time that produced the strongest hybridization signals. Using this method of digestion time control, an additional 41 cases were evaluated for FISH with various types of probe. Monitoring under the microscope could be more spaced if the morphology did not change after the first visual control and could be adapted to the type of sample (in general, endoscopic samples, total digestion time of about 10 min; routine biopsies, 15 to 30 min; autopsy samples, 20 to 40 min). In every case, the appearance of the fernlike pattern correlated with proper hybridization signal. Monitoring digestion time for the appearance of fernlike structures is a useful method for improving reproducibility of FISH technique on paraffin-embedded samples. It is particularly useful when dealing with samples under heterogeneous fixation conditions (consultations, autopsies, etc.), because it eliminates the need for repetition.     

Fluorescence in situ hybridization analysis of HER-2/neu in brushings of normal oral mucosa

Oncogene alterations have been clearly demonstrated to be related to the carcinogenesis and progression of oral squamous cell carcinoma (OSCC). However, the analysis of these alterations for screening and early diagnostic purposes generally requires invasive techniques for surgical removal of pathological epithelium. The aim of the present study was to assess the feasibility of fluorescence in situ hybridization (FISH) analysis of HER-2/neu amplification in oral mucosa brushings and to compare the HER-2/neu status with the history and smoking and drinking habits of healthy subjects. Cells obtained by centrifugation of oral brushings from 21 subjects (overall no. of cells: 5125) were suspended in physiological saline and fixed onto two slides for cytological evaluation and FISH analysis (dual-target, dual-color fluorescence assay) of the HER-2/neu gene and CEP17 centromere. A mean of 89.8% of the cells showed two HER-2/neu signals and a mean of 94% had two CEP17 signals at fluorescent microscopy. Finally, a mean of 96% of cells with HER-2/neu / CEP17 had a ratio equal to 1. No association between smoking and drinking habits, age and the HER-2/neu and CEP17 characteristics evaluated by FISH was found.     

Catastrophic household expenditure associated with out-of-pocket payments for dental healthcare in Spain

The European Journal of Health Economics - To estimate the prevalence of catastrophic health expenditure due to dental healthcare (CHED) in Spain, quantify its intensity and examine the related...     

Abordajes en cirugía tiroidea

Thyroidectomy is the most frequent procedure in endocrine surgery. The conventional approach through a collar incision, as described by Kocher in XIX^th century, has become the “gold standard”. It is continuously evolving in spite of, many years ago, it showed to be safe and efficient with quality standards difficult to beat.Endoscopic and robotic surgery have developed “new approaches” to thyroid in order to improve the cosmetic results, looking even for invisible scars.We have done a thoughtful review of most of them trying to understand their benefits and drawbacks.Currently none of these “new approaches” have been shown to be better than conventional open thyroidectomy beyond offering a better cosmetic result. Besides, only a small percentage of patients can benefit of them. However, most of these approaches will remain if they treat the diseased thyroid and also improve the quality of life of our patients.     

Resecciones pulmonares anatómicas por vía robótica: análisis de la curva de aprendizaje

IntroductionRobotic surgery has become a safe and effective approach for the treatment of pulmonary surgical pathology. However, the adoption of new surgical techniques requires the evaluation of the learning curve. The objective of this study is to analyze the learning curve of robotic anatomical lung resections.MethodsRetrospective analysis of all robotic anatomical lung resections performed by the same surgeon between June 2018 and March 2020. The learning curve was evaluated using CUSUM charts to estimate trend changes in surgical time, surgical failure and the occurrence of post-operative cardiorespiratory complications throughout the sequence of cases.ResultsThe study included a total of 73 cases. The median duration of all complications was 120 min (interquartile range: 90-150 min), the prevalence of surgical failure was 23.29%, while 4/73 patients had any postoperative cardiorespiratory complication. Based on the CUSUM analysis, the learning curve was divided into 3 different phases: phase i (from the first to the 14th intervention), phase ii (between the 15th and 30th intervention) and phase iii (from the 31st intervention).ConclusionsThe learning curve for robotic anatomical lung resections can be divided into 3 phases. The technical competence that guarantees satisfactory perioperative outcomes was achived in phase iii from the 31st intervention.     

Craniofacial Development: Neural Crest in Molecular Embryology

Craniofacial development, one of the most complex sequences of developmental events in embryology, features a uniquely transient, pluripotent stem cell-like population known as the neural crest (NC). Neural crest cells (NCCs) originate from the dorsal aspect of the neural tube and migrate along pre-determined routes into the developing branchial arches and frontonasal plate. The exceptional rates of proliferation and migration of NCCs enable their diverse contribution to a wide variety of craniofacial structures. Subsequent differentiation of these cells gives rise to cartilage, bones, and a number of mesenchymally-derived tissues. Deficiencies in any stage of differentiation can result in facial clefts and abnormalities associated with craniofacial syndromes. A small number of conserved signaling pathways are involved in controlling NC differentiation and craniofacial development. They are used in a reiterated fashion to help define precise temporospatial cell and tissue formation. Although many aspects of their cellular and molecular control have yet to be described, it is clear that together they form intricately integrated signaling networks required for spatial orientation and developmental stability and plasticity, which are hallmarks of craniofacial development. Mutations that affect the functions of these signaling pathways are often directly or indirectly identified in congenital syndromes. Clinical applications of NC-derived mesenchymal stem/progenitor cells, persistent into adulthood, hold great promise for tissue repair and regeneration. Realization of NCC potential for regenerative therapies motivates understanding of the intricacies of cell communication and differentiation that underlie the complexities of NC-derived tissues.     

BCL-2--general considerations

BCL-2 protein is a oncoprotein considered to have an important role in the regulation of programmed cell death--apoptosis. The intracellular localization, the relation with other oncoproteins, the antioxidant function and the pathological implications are discussed.     

Tumor proliferative activity and response to first-line chemotherapy in advanced breast carcinoma

Summary The relationship between tumor proliferative activity and response to first-line chemotherapy and survival was investigated in 76 advanced breast cancer patients. Proliferative activity was determined by means of Ki-67 immunohistologic staining on primary tumors (55 patients) or at the relapse site (21 patients), and was classified as low ( 25% of stained cells) or high (> 25% of stained cells). The usual WHO response criteria were used. The median duration of follow-up was 18 months (range 3–58).Forty-seven patients (62%) had tumors with low, and 29 (38%) had tumors with a high rate of proliferative activity. The two groups were well balanced in terms of important variables such as disease-free survival, performance status, age, menopausal status, and the type of first-line chemotherapy (anthracycline-based regimens versus cyclophosphamide-methotrexate-5-fluorouracil). The estrogen receptor (ER) content, measured by means of immunohistochemical assay, was markedly different in the two groups, with 27/47 tumors with low proliferative activity (57%) and 6/29 with high-proliferative activity (21%) being ER positive ( 45% of stained cells) (p = 0.003). Moreover, a significant difference in the metastatic pattern was also evident, with a higher incidence of bone and a lower incidence of soft tissue metastases in the group of patients with tumors with low proliferative activity (p = 0.004). Overall, 10/47 responses (21%: PR = 7, and CR = 3) were observed in the group with a low rate of proliferative activity, versus 14/29 (48%: PR = 9, and CR = 5) in the group with highly proliferative tumors, the difference being statistically significant (p = 0.03). When a multivariate analy-sis was performed, the only factor that retained independent prognostic significance was the predominant site of disease, particularly soft tissues (p = 0.003). Despite the difference in response rate, when survival analysis was performed according to the Kaplan-Meier method, no significant difference was observed in the two groups, but when the analysis was limited to responsive patients, the median survival observed in those with a low and those with a high rate of proliferation was 35 and 19 months respectively (p = 0.02). The same results were obtained when multivariate survival analysis was carried out using Cox's regression model. These data suggest that there is a link between tumor proliferative activity and response to chemotherapy in advanced breast cancer, and may indicate the need to use more intensive treatments in selected patients with highly proliferative tumors.Presented in part at the Annual Meeting of the American Society of Clinical Oncology, May 14–17, 1994, Dallas, TX, USA