Prognostic Significance of the Expression of Immuno-Histochemically Detectable Differentiation Markers in Laryngeal Carcinomas

Expression of immunocytochemically detectable markers in 100 cases of laryngeal carcinomas, homogeneous for staging and treatment, was correlated with clinical evolution of the disease. Follow-up for a minimum of 5 years was obtained in all cases. Paraffin sections were re-cut and stained in immunoperoxidase with monoclonal KL1, detecting medium-to-low molecular weight keratins, and with monoclonal HMFG2, revealing a surface glycoprotein. Expression of KL1-related antigen did not correlate with prognosis, whereas cases extensively positive for monoclonal HMFG2 (more than 50% cells stained) had a significantly better recurrence-free rate. In a group of tumors classified as Grade 3 (histologically poorly differentiated) and expressing a low degree of HMFG2-detectable surface glycoprotein (< 50 % cells stained), a high rate of recurrences (93%) was observed. This study indicates that the combined use of morphologic and biologic (immunohistochemical) criteria may constitute an independent parameter of primary importance in predicting the evolution of laryngeal carcinomas.

Ankle fracture: radiographic approach according to the Lauge-Hansen classification

Ankle fractures account for 9 % of fractures (Clare in Foot Ankle Clin 13(4):593-610, 1) representing a significant portion of the trauma workload; proximal femoral fractures are the only lower limb fracture to present more frequently. Ankle fractures have a bimodal age distribution with peaks in younger males and older females (Arimoto and Forrester in AJR Am J Roentgenol 135(5):1057-1063, 2). There has been threefold increase in the incidence among elderly females over the past three decades (Haraguchi and Armiger in J Bone Joint Surg Am 91(4):821-829, 3). In 1950, Lauge-Hansen devised a classification of ankle fractures based on the position of the foot and the deforming force at the time of injury. This has been widely accepted by orthopedists, but is not in general use by radiologists. Identification of the fractures and classification of the type of injury allows diagnosis of the otherwise occult ligamentous injuries. Three radiographic views of the ankle (anteroposterior, mortise, and lateral) are necessary to classify an injury with the Lauge-Hansen system. Two additional criteria are also necessary: the position of the foot at the time of injury and the direction of the deforming force.

Long maternal separation has protective effects in rats exposed to activity-based anorexia

This study examined the effect of three neonatal treatments of maternal separation during infancy in young adult rats exposed to standard activity-based anorexia (ABA) consisting of food restriction plus free access to an activity wheel. During the first 20 postnatal days of life rat pups were exposed to periods of either brief maternal separation (BMS, 15 min), long maternal separation (LMS, 180 min), or were non-handled (NH). Thereafter, male and female rats were exposed to ABA. Neonatal treatment produced no significant differences in the survival time of male rats, whereas survival was greater in female rats exposed to LMS than in NH rats under ABA procedure. In conclusion, prolonged maternal separation appears to promote resistance in female animals subjected to harsh ABA life-threatening conditions.

High ambient temperature reverses hypothalamic MC4 receptor overexpression in an animal model of anorexia nervosa

The potential involvement of the melanocortin system in the beneficial effects of heat application in rats submitted to activity-based anorexia (ABA), an analogous model of anorexia nervosa (AN), was studied. Once ABA rats had lost 20% of body weight, half of the animals were exposed to a high ambient temperature (HAT) of 32 degrees C, whereas the rest were maintained at 21 degrees C. Control sedentary rats yoked to ABA animals received the same treatment. ABA rats (21 degrees C) showed increased Melanocortin 4 (MC4) receptor and Agouti gene Related Peptide (AgRP) expression, and decreased pro-opiomelanocortin (POMC) mRNA levels (Real Time PCR), with respect to controls. Heat application increased weight gain and food intake, and reduced running rate in ABA rats, when compared with ABA rats at 21 degrees C. However, no changes in body weight and food intake were observed in sedentary rats exposed to heat. Moreover, heat application reduced MC4 receptor, AgRP and POMC expression in ABA rats, but no changes were observed in control rats. These results indicate that hypothalamic MC4 receptor overexpression could occur on the basis of the characteristic hyperactivity, weight loss, and self-starvation of ABA rats, and suggest the involvement of hypothalamic melanocortin neural circuits in behavioural changes shown by AN patients. Changes in AgRP and POMC expression could represent an adaptative response to equilibrate energy balance. Moreover, the fact that HAT reversed hypothalamic MC4 receptor overexpression in ABA rats indicates the involvement of brain melanocortin system in the reported beneficial effects of heat application in AN. A combination of MC4 receptor antagonists and heat application could improve the clinical management of AN.

[Factors that affect the Hoffmann reflex as a tool used in neurophysiological examination]

INTRODUCTION

The Hoffmann reflex, or H-reflex, which is the electrical equivalent of the myotatic reflex, is a very valuable tool for evaluating the reflex pathway and for investigating the mechanisms that regulate the intensity of its response. Yet, the complex interaction of the H-reflex circuit with other neural components requires a tight-fit recording protocol.

DEVELOPMENT

In this paper we present a review of the main technical, physiological and methodological factors that affect the recording of the H-reflex when used as an instrument for neurophysiological exploration. The paper reviews aspects concerning the method of stimulation, recording and analysing the reflex response. The physiological mechanisms that interact to modulate the amplitude of the H-reflex, such as pre-synaptic inhibition, post-activation depression and the excitability of the motoneurons, are described and the different methods used to control the variations that arise in each case are also outlined. Lastly, a summary of the main points to be borne in mind when recording the H-reflex is presented.

CONCLUSIONS

Due to the large number of variables and the non-linear way they interact with one another, we must proceed with care when drawing conclusions from the discussion of the results obtained under such strict protocols. Progress also has to be made in the development and application of new mathematical, statistical and modelling tools in order to achieve a more accurate interpretation of the findings that are observed.

Analysis of regulatory regions of the ciliary neutrophic factor gene in transgenic mice

In order to study the regulatory regions of the human ciliary neurotrophic factor (CNTF) gene we made constructs containing sequences upstream and downstream of CNTF coding regions and the lacZ gene and analysed their expression in transgenic mice. We show that 240 bp upstream of the translation start codon are sufficient for the transcription of the lacZ gene. A further 4 kb upstream sequence is required for the expression of the transgene in Schwann cells. These two upstream regions together with a 2 kb downstream fragment drive high level of expression of the lacZ gene in the sciatic nerve. Our results indicate that these three fragments contain regulatory regions able to mimic the CNTF expression pattern in the mouse peripheral nervous system.

Nonspecific in situ hybridization reaction in neuroendocrine cells and tumors of the gastrointestinal tract using oligonucleotide probes

Oligonucleotides used in in situ hybridization (ISH), regardless of their sequence specificity, bind to neuroendocrine (NE) cells in normal gastrointestinal mucosa and tumors. This nonspecific binding, presumably related to the presence in NE cells of hidden NH2 groups of obscure origin, can be prevented by acetic anhydride treatment of the sections. This is a routine step in several ISH protocols but not in all. This study emphasizes the need to establish safe protocols and controls to check the specificity of ISH procedures.

Secretogranin II expression in Ewing's sarcomas and primitive neuroectodermal tumors

Production of chromogranins, the acidic components of the chromaffin granules regarded as specific neuroendocrine markers, was analyzed by immunocytochemistry and hybridization (Northern blotting and in situ hybridization) in primary lesions and cell lines of Ewing's sarcomas, primitive neuroectodermal tumors (PNETs), and neuroblastomas. Antibodies and probes specific for chromogranin A (CgA), chromogranin B (CgB), and secretogranin II (SgII) were used. Ewing's sarcomas and PNETs, unlike neuroblastomas, were negative for CgA and CgB. Two primary Ewing's sarcomas, one primary PNET (an Askin tumor), and one PNET cell line (TC32) were found to strongly express the SgII gene, as shown by the presence of specific mRNA. This result supports the hypothesis that some Ewing's sarcomas represent a most primitive form of neuroectodermal tumor; in addition, it indicates a diagnostic role of SgII in cases of Ewing's sarcomas and PNETs.

Peri and intratumoral macrophage infiltration in laryngeal carcinoma. An immunohistochemical study

The role of macrophages infiltrating tumor tissue is still poorly explained; the data available are sparse and, to the best of our knowledge, there is no study relating the characteristics of such infiltration to tumor evolution and final outcome. We decided to investigate the spatial relationships between macrophages and neoplastic tissue and their possible prognostic significance on a series of laryngeal carcinomas (98 patients) all of which were operated in our Department and had a follow-up of at least 3 years. In order to identify the macrophage infiltration, formaline-fixed/paraffin-mounted specimens of the tumor were treated with MoAb HAM56. No statistically significant relationship could be established between the degree of macrophage infiltration and the clinical outcome (recurrence), even when the N status was taken into account (N- vs. N+). However, a clear trend was observed when the analysis was confined to grade 3 cases, where the presence of a significant number of macrophages was correlated with a higher probability of recurrence.

[Prognostic significance of macrophage infiltration in laryngeal carcinoma]

We investigated the relationships between tumor associated macrofages (TAM) and tumor tissues and their possible prognostic significance in a laringeal carcinomas of patients operated in our Department for sovraglottic or total laringectomy. In our analysis we found a positive trend in Grade 3, but we could not find any correlations in the other cases. That shows that TAM have antithetic activities in the life of neoplasia.