Assessment of the intrasinusidal volume before and after maxillary sinus augmentation using mri - a pilot study of eight patients.

PURPOSE: The purpose of this study was to evaluate the suitability, accuracy, and reliability of a non-invasive 3-Tesla magnetic resonance imaging technique (3 T-MRI) for the visualization of maxillary sinus grafts in comparison to conventional, X-ray-based, established standard imaging techniques. METHODS: A total of eight patients with alveolar bone atrophy who required surgical sinus floor augmentation in the course of dental implantation were included in this pilot study. Alongside pre-operative cone-beam computed tomography (CBCT), 3 T-MRI was performed before and 6 months after sinus floor augmentation. Two investigators measured the maxillary sinus volume preoperatively and after bone augmentation. RESULTS: In all cases, MRI demonstrated accurately the volumes of the maxillary sinus grafts. Following surgery, the bony structures suitable for an implant placement increased at an average of 4.89 cm3, corresponding with the decrease of the intrasinusidal volumes. In general, interexaminer discrepancies were low and without statistical significance. CONCLUSION: In this preliminary study, we could demonstrate the feasibility of MRI bone volume measurement as a radiation-free alternative with comparable accuracy to CT/CBCT before procedures like sinus floor augmentation. Nevertheless, costs and artifacts, also present in MRI, have to be taken into account. Larger studies will be necessary to justify the practicability of MRI bone volume evaluation.

[Hearing protectors in musicians]. / Gehörschutz bei Musikern.

The ENT physician and specialist in musician's medicine is consistently confronted with the issue of hearing protection, since musicians exposed to high sound levels due to their profession, and who are often concerned about their hearing, refer to him. Furthermore, this topic has gained more relevance since a noise exposure limit for professional musicians was issued in February 2008 by the EC guidelines for occupational health and safety regarding "Noise" (2003/10/EC). The present article gives an outline of the recent state of knowledge about sound pressure levels, hearing risks, as well as the use of hearing protection for musicians.

[Hearing damage caused by impulse noise]. / Hörschäden durch Impulslärm.

Methods for judging the danger of hearing impairment caused by continuous noise are known and have been included in standards. There are no equally accepted criteria to distinguish between dangerous and harmless impulsive noise. For this reason, a mobile measuring system has been developed, that can determine and record parameters of impulsive noise in industrial environments. The parameters were chosen with respect to the properties of the human ear, and to provide an intercomparison of currently used or proposed measuring methods. In one case, the frequency response of the outer and middle ear is simulated electrically in order to evaluate the signal that would reach the inner ear, where damage usually occurs. The data collected at the operators position of industrial machines will be correlated with the corresponding audiometric evaluation of hearing damage conducted by SUVA (Swiss National Insurance Fund), in order to find damage risk criteria for impulsive noise.

The sound exposure of the audience at a music festival.

During the Paleo Festival in Nyon, Switzerland, which took place from 24th to 29th July 2001, ten volunteers were equipped each evening with small sound level meters which continuously monitored their sound exposure as they circulated among the various festival events. Sound levels at the mixing console and at the place where people are most heavily exposed (in front of the speakers) were measured simultaneously. In addition, a sample of 601 people from the audience were interviewed over the six days of the festival and asked their opinion of sound level and quality, as well as provide details of where in the arena they preferred to listen to the concerts, whether they used ear plugs, if they had experienced any tinnitus, and if so how long it had persisted. The individual sound exposure during a typical evening was on average 95 dB(A) although 8% of the volunteers were exposed to sound levels higher then 100 dB(A). Only 5% of the audience wore ear plugs throughout the concert while 34% used them occasionally. While some 36% of the people interviewed reported that they had experienced tinnitus after listening to loud music, the majority found both the music quality and the sound level good. The sound level limit of 100 dB(A) at the place where the people are most heavily exposed seems to be a good compromise between the public heath issue, the demands of artists and organisers, and the expectations of the public. However, considering the average sound levels to which the public are exposed during a single evening, it is recommended that ear plugs be used by concert-goers who attend more than one day of the festival.

[The microscopical identification of fruits from Gevuina avellana Molina (author's transl)]. / Zur mikroskopischen Identifizierung von chilenischen Haselnüssen (Gevuina avellana Molina).

The fruits of Gevuina avellana Molina, which in Chile are eaten like hazel-nuts, were subjected to microscopic examination. There are several anatomical characteristics, useful for differentiation. The anatomy of these nuts was then compared with that of hazel-nuts (Corylus avellana L.) is added.

Gluconeogenesis in isolated nephron segments of the rabbit.

Glucose production rates from lactate and pyruvate in individually isolated segments of the rabbit nephron were measured using the enzymatic cycling method. Glucose production per mm length was uniformly high in the whole proximal tubule including the straight descending portion. Lower values were observed in the thin descending limb and in the thick ascending limb of Henle's loop. We believe that this study demonstrates two advantages of the approach suggested by Burg and Orloff to study renal metabolism in different parts of the nephron: first, specific differences in the metabolism of indivudual nephron segments can be detected directly, second, metabolic rates are easily to be compared with physiological data obtained by micropuncture and microperfusion since the common point of reference is the length of the nephron segments.

CTGF (IGFBP-rP2) is specifically expressed in malignant lymphoblasts of patients with acute lymphoblastic leukaemia (ALL).

Connective tissue growth factor (CTGF) is a major chemotactic and mitogenic factor for connective tissue cells. The amino acid sequence shares an overall 28-38% identity to IGFBPs and contains critical conserved sequences in the amino terminus. It has been demonstrated that human CTGF specifically binds IGFs with low affinity and is considered to be a member of the IGFBP superfamily (IGFBP-rP2). In the present study, the expression of CTGF (IGFBP-rP2) in human leukaemic lymphoblasts from children with acute lymphoblastic leukaemia (ALL) was investigated. RNA samples from tumour clones enriched by ficoll separation of bone marrow or peripheral blood mononuclear cells (MNC) from 107 patients with childhood ALL at diagnosis and 57 adult patients with chronic myeloid leukaemia (CML) were studied by RT-PCR. In addition MNC samples from children with IDDM and cord blood samples from healthy newborns were investigated as control groups. Sixty-one percent of the patients with ALL (65 of 107) were positive for CTGF (IGFBP-rP2) expression. In the control groups, no expression of CTGF (IGFBP-rP2) in peripheral MNC was detected, and in the group of adult CML patients only 3.5% (2 of 57) were positive for this gene. The role of CTGF (IGFBP-rP2) in lymphoblastic leukaemogenesis requires further evaluation, as does its potential utility as a tumour marker.

Expression of components of the IGF signalling system in childhood acute lymphoblastic leukaemia.

BACKGROUND: Alterations in the insulin-like growth factor (IGF) system have been reported for different tumours. They are of particular interest in the search for new prognostic and therapeutic approaches in cancer. In childhood acute lymphoblastic leukaemia (ALL) the amount of "tumour mass" at diagnosis can exceed 1 kg. To understand the endocrine, paracrine, and autocrine potential of the malignant transformed progenitor cells, the ability of these cells to express components of the IGF system needs to be investigated. AIM: To characterise the expression pattern of genes of the IGF system in malignant lymphoblasts of children suffering from ALL. METHODS: Reverse transcription polymerase chain reaction of Ficoll separated mononuclear cells from 142 children with ALL, 127 cord blood samples, and 55 blood samples of age matched controls were studied. RESULTS: The expression of IGF-I, IGF-II, IGF binding protein 5 (IGFBP-5), and CTGF (IGFBP-rP2) was seen in a higher proportion of mononuclear cells of patients with ALL than in controls. Patients with ALL who were in continuous remission had a lower percentage of IGFBP-2 and IGFBP-3 expressing mononuclear cells at diagnosis than did those who developed a relapse. Only malignant lymphoblasts of B cell origin showed expression of CTGF (IGFBP-rP2). Malignant lymphoblasts of T cell origin more often expressed IGFBP-2 and IGFBP-5, whereas IGF-II and IGFBP-3 expression was seen more often in lymphoblasts of B cell origin. CONCLUSIONS: Malignant lymphoblasts of patients with ALL express components of the IGF system and therefore promote their own growth in an autocrine, paracrine, or endocrine manner. Whether these components will be useful as prognostic factors in the stratification of ALL treatment in children needs to be evaluated.

Congenital hydrocephalus internus and aqueduct stenosis: aetiology and implications for genetic counselling.

UNLABELLED: Genetic counselling in families with congenital hydrocephalus internus (CHI) in combination with aqueduct stenosis (AS) is often difficult due to an uncertain aetiology. We present a series of 35 patients with CHI and AS focusing on the aetiology and presumed recurrence risk for siblings. In 13 patients (37.1%) a genetic aetiology was identified with an increased recurrence risk for siblings. The relative frequency of patients with X-linked hydrocephalus in our sample was in accordance with the literature (2/35), but was more frequent in other diseases with Mendelian inheritance. CONCLUSION: In addition to the well-known X-linked and autosomal recessive forms of aqueduct stenosis with hydrocephalus, this malformation can occur in other diseases with Mendelian inheritance. This finding is of considerable importance for genetic counselling and prognosis.