Factors controlling accumulation of organic carbon in a rift-lake, Oligocene Vietnam

Understanding of the processes of petroleum source rock (SR) accumulation in lacustrine rift basins and the behavior of lake systems as long-term carbon sinks is fragmentary. Investigation of an 800 m thick (500 m core and ~ 300 m outcrop), deep-lacustrine, Oligocene section in Vietnam, provides a rare insight into the controls and deposition of organic carbon (OC) and SR formation in continental rift basins. A multidisciplinary dataset, combining elemental data, inorganic and organic geochemistry with sedimentology, shows that the richest alginite-prone, sapropelic SR developed during periods of relative tectonic quiescence characterized by moderate primary productivity in a mainly dysoxic lacustrine basin. Increased rift activity and further development of graben morphology intensified water column stratification and anoxia, which hindered nutrient recycling. Sapropelic organic matter (OM) continued to accumulate, but with increasing amorphous OM content and decreasing total OC values. Periods of increased seasonality were characterized by thermocline weakening, enhanced mixing of water columns, increased primary productivity and diatom blooming. The results suggest that a change from dysoxia towards anoxia or extreme primary productivity does not necessarily enhance OC burial and SR quality. External nutrient input from a phosphate-rich hinterland is sufficient for sapropel formation, whereas the main limiting factor is methanogenesis.

Danish guidelines on management of otitis media in preschool children

INTRODUCTION

Otitis media is one of the most common diseases in small children. This underlines the importance of optimizing diagnostics and treatment of the condition. Recent literature points toward a stricter approach to diagnosing acute otitis media (AOM). Moreover, ventilating tube treatment for recurrent AOM (RAOM) and chronic otitis media with effusion (COME) has become the most frequently performed surgical procedure in pre-school children. Therefore, the Danish Health and Medicines Authority and the Danish Society of Otorhinolaryngology, Head and Neck Surgery deemed it necessary to update the Danish guidelines regarding the diagnostic criteria for acute otitis media and surgical treatment of RAOM and COME.

METHODS

The GRADE system (The Grading of Recommendations Assessment, Development and Evaluation) was used in order to comply with current standards of evidence assessment in formulation of recommendations. An extensive literature search was conducted between July and December 2014. The quality of the existing literature was assessed using AGREE II (Appraisal of Guidelines for Research & Evaluation), AMSTAR (assessing the Methodological Quality of Systematic Reviews), QUADAS-2 (Quality of Diagnostic Accuracy Studies), Cochrane Risk of Bias Tool for randomized trials and ACROBAT-NRSI (A Cochrane Risk of Bias Assessment Tool for Non-Randomized Studies). The working group consisted of otolaryngologists, general practitioners, pediatricians, microbiologists and epidemiologists.

CONCLUSION

Recommendations for AOM diagnosis, surgical management for RAOM and COME, including the role of adenoidectomy and treatment of ventilating tube otorrhea, are proposed in the guideline.

A randomised crossover comparison of manikin ventilation through Soft Seal®, i-gel™ and AuraOnce™ supraglottic airway devices by surf lifeguards

Forty surf lifeguards attempted to ventilate a manikin through one out of three supraglottic airways inserted in random order: the Portex® Soft Seal®; the Intersurgical® i-gel™; and the Ambu® AuraOnce™. We recorded the time to ventilate and the proportion of inflations that were successful, without and then with concurrent chest compressions. The mean (SD) time to ventilate with the Soft Seal, i-gel and AuraOnce was 35.2 (7.2)s, 15.6 (3.3)s and 35.1 (8.5) s, respectively, p < 0.0001. Concurrent chest compression prolonged the time to ventilate by 5.0 (1.3-8.1)%, p = 0.0072. The rate of successful ventilations through the Soft Seal (100%) was more than through the AuraOnce (92%), p < 0.0001, neither of which was different from the i-gel (97%). The mean (SD) tidal volumes through the Soft Seal, i-gel and AuraOnce were 0.65 (0.14) l, 0.50 (0.16) l and 0.39 (0.19) l, respectively. Most lifeguards (85%) preferred the i-gel. Ventilation through supraglottic airway devices may be considered for resuscitation by surf lifeguards.

Enzyme replacement therapy for alpha-mannosidosis: 12 months follow-up of a single centre, randomised, multiple dose study

BACKGROUND

Alpha-mannosidosis (OMIM 248500) is a rare lysosomal storage disease (LSD) caused by alpha-mannosidase deficiency. Manifestations include intellectual disabilities, facial characteristics and hearing impairment. A recombinant human alpha-mannosidase (rhLAMAN) has been developed for weekly intravenous enzyme replacement therapy (ERT). We present the preliminary data after 12 months of treatment.

METHODS

This is a phase I-II study to evaluate safety and efficacy of rhLAMAN. Ten patients (7-17 y) were treated. We investigated efficacy by testing motor function (6-minutes-Walk-Test (6-MWT), 3-min-Stair-Climb-Test (3-MSCT), The Bruininks-Oseretsky Test of Motor Proficiency (BOT2), cognitive function (Leiter-R), oligosaccharides in serum, urine and CSF and Tau- and GFA-protein in CSF.

RESULTS

Oligosaccharides: S-, U- and CSF-oligosaccharides decreased 88.6% (CI -92.0 -85.2, p < 0.001), 54.1% (CI -69.5- -38.7, p < 0,001), and 25.7% (CI -44.3- -7.1, p < 0.05), respectively. Biomarkers: CSF-Tau- and GFA-protein decreased 15%, p < 0.009) and 32.5, p < 0.001 respectively. Motor function: Improvements in 3MSCT (31 steps (CI 6.8-40.5, p < 0.01) and in 6MWT (60.4 m (CI -8.9 -51.1, NS) were achieved. Cognitive function: Improvement in the total Equivalence Age of 4 months (0.34) was achieved in the Leiter R test (CI -0.2-0.8, NS).

CONCLUSIONS

These data suggest that rhLAMAN may be an encouraging new treatment for patients with alpha-mannosidosis.The study is designed to continue for a total of 18 months. Longer-term follow-up of patients in this study and the future placebo-controlled phase 3 trial are needed to provide greater support for the findings in this study.

Elimination of mange mites Sarcoptes scabiei var. suis from two naturally infested Danish sow herds using a single injection regime with doramectin

Attempts to eliminate Sarcoptes scabiei var. suis were made in 2 naturally infested sow herds, by intramuscular (i.m.) injection of doramectin (Dectomax, Pfizer, New York, USA). A single injection strategy was used. In one of the herds, the environment was treated with an acaricide following dry cleaning of floors, walls and equipment. In the second herd, no environmental treatment was performed. Results were measured by skin lesion scoring, ear scrapings to show Sarcoptes scabiei var. suis, and calculating rubbing index throughout the observation period of 20 months following treatment. Skin lesion scores decreased and stayed low following treatment for the entire observation period. Live Sarcoptes scabiei var. suis mites were isolated prior to treatment from both herds, but not following treatment. Rubbing index decreased following treatment, but was occasionally at or above 0.4. The results of these studies indicate that elimination of Sarcoptes scabiei var. suis from 2 naturally infested herds was successful, using doramectin in a single injection strategy. Precautions must be taken to ensure adequate dosing of every pig, and to avoid reinfestation due to poor biosecurity.

Urinary albumin excretion and 24-hour blood pressure as predictors of pre-eclampsia in Type I diabetes

AIMS/HYPOTHESIS

To evaluate the value of 24-h blood pressure monitoring compared to office blood pressure and urinary albumin excretion in predicting pre-eclampsia in Type I (insulin-dependent) diabetes mellitus.

METHODS

The study included 136 consecutive pregnancies in Caucasian women with Type I diabetes before gestation without diabetic nephropathy, anamnestic hypertension or early abortion. Values of urinary albumin excretion and office blood pressure before pregnancy and the HbA1C value at the time of conception were obtained. Microalbuminuria was defined as urinary albumin excretion of 30-300 mg/24 h in two out of three consecutive urine samples. Single measurements of 24-h urinary albumin excretion, office blood pressure and HbA1C were done five 5 times during pregnancy. In a subgroup of 74 women 24-h blood pressure measurements were done at 10 and 28 weeks of gestation. Pre-eclampsia was defined as office blood pressure higher than 140/90 mmHg accompanied by proteinuria above 0.3 g/24 h later than 20 weeks of gestation.

RESULTS

Urinary albumin excretion and systolic blood pressure were higher before and throughout pregnancy in 14 women developing pre-eclampsia compared with women remaining normotensive (p <0.001; p < 0.05, respectively). By logistic regression analysis the best predictor for pre-eclampsia was microalbuminuria before pregnancy (p < 0.05) with no additive predictive effect of 24-h blood pressure or office blood pressure measurement. The night:day ratio of blood pressure was similar in the two groups.

CONCLUSION/INTERPRETATION

Microalbuminuria before pregnancy is the strongest predictor of pre-eclampsia in Type I diabetes. Measuring 24-h blood pressure early in pregnancy did not improve the ability to identify women at risk.

Pressure transfer between intracranial and cochlear fluids in patients with Meniere's disease

OBJECTIVES

To elucidate the pressure transfer between intracranial and labyrinthine fluids in patients with well-defined unilateral Meniere's disease.

STUDY DESIGN

Eleven patients previously exposed to hypobaric pressure agreed to be investigated further with the tympanic membrane displacement (TMD) technique. TMD was used to indirectly analyze perilymph pressure changes as the result of changes in body position.

METHODS

Repeated measurements for both the diseased and the healthy ears were made with the patients supine and then in a sitting position. The TMD parameters for the maximum inward displacement, the Vi, and the mean volume displacement, the Vm, were calculated and compared.

RESULTS

The paired comparison showed statistically significant larger Vi values for both ears in the supine position. A similar tendency was observed for the Vm value. This difference of the Vi was significantly larger for the diseased ear compared with the currently healthy ear. The results were compared to the audiometric and electrocochleographic results previously obtained on the same patients when they were subjected to hypobaric pressure. Patients who experienced the largest differences in hearing level thresholds in the lower frequencies also showed the greatest differences in TMD values as the result of postural changes.

CONCLUSIONS

Despite the limited number, the statistically supported results suggest a relation between the efficiency of the routes of pressure transfer and the observed effect of hypobaric exposure. The results also indicate that for the patients tested, the routes of communication are more effective in the diseased ear than in the healthy ear--a condition that may relate to the pathogeneses of Meniere's disease.

Gait disturbance interpreted as cerebellar ataxia after MMR vaccination at 15 months of age: a follow-up study

Measles, mumps and rubella (MMR) vaccination was included in the Danish childhood vaccination programme in 1987. During the following 10-y period, 550 notification records of adverse events after MMR vaccination at 15 mo of age have been registered, and a total of 41 notifications have included "gait disturbance". This corresponds to a frequency of 8 per 100,000 doses of MMR vaccine used for 15-mo-old children. The symptoms and signs are characteristic of cerebellar ataxia. In 28 notifications, the descriptions by the doctors included only "gait disturbance", while in 13 an additional interpretation was included. Thirty-two parents (78%) filled in a questionnaire and 26 (63%) agreed to participate in a clinical follow-up study. The gait disturbance symptoms mainly occurred 7-14 d after the vaccination, and the duration was median 1-2 wk (range 1 d to more than 4 mo). One-third of the children had symptoms lasting more than 2 wk. Significantly more children with long duration of symptoms had some kind of complaint or clinical signs at the follow-up in 1997. Gait disturbance registered after MMR vaccination seems to be more frequent than hitherto reported. Most cases are mild and short-lasting and a longer duration of symptoms seems to be predictive of late sequelae. A clinical diagnosis of cerebellar ataxia after MMR and the exact frequency of this adverse event remains to be tested in prospective studies.

The acoustic reflex threshold: not predictive for loudness perception in normally-hearing listeners

The working hypothesis of an ongoing study is that the quick and reliable procedure of acoustic reflex threshold (ART) determination in conjunction with measurements of HTL may yield accurate estimates of loudness. The aim of this study was to investigate whether differences in loudness in normally-hearing subjects are reflected in the ARTs and to collect normal material with respect to pure-tone elicited ART and loudness categories. Categorical loudness scaling (CLS) and ART measurements were performed at frequencies of 0.5, 1, 2 and 4 kHz in 60 normally-hearing subjects (HTL<20 dB HL, 26 males, 34 females, aged 21-63 years) with no history or sequelae of middle ear disease. Subjects reporting disturbing tinnitus were excluded. The results show that the ART is not a predictor of individual loudness perception for normally-hearing subjects. Using a numerical scale (HTL=0, 'very soft'=5, 'soft'=15, 'OK'=25, 'loud'=35, 'very loud'=45 and 'too loud'=50) loudness for pure tones grows almost linearly at approximately 0.4 arbitrary loudness units per dB below the 'loud' category. Above the 'loud' category the slope is around 1 unit per dB. The median ART was 85 dB HL at frequencies of 0.5, 1, 2 and 4 kHz. No differences in loudness perception across frequencies were found.

The relationship between the acoustic reflex threshold and levels of loudness categories in hearing-impaired listeners

When applied as a tool for hearing aid fitting, categorical loudness scaling (CLS) is time consuming and not feasible in all subjects. It is therefore desirable to use objective measures for accurate prediction of loudness categories among hearing-impaired individuals. The present study aimed at exploring whether loudness perception at the ART is constant with varying hearing threshold. Seventy-five subjects with various degrees of hearing impairment, measurable acoustic reflex and normal middle ear function participated. The HTLs, ARTs and the levels of six loudness categories at frequencies 0.5, 1, 2 and 4 kHz were determined for all subjects. Loudness at the ART was found to be correlated with the amount of hearing loss. On the basis of these results, it is concluded that the ART cannot be used for accurate estimation of loudness in hearing-impaired subjects.

Loudness perception is influenced by long-term hearing aid use

The aim of this study was to explore possible differences in the perception of loudness between long-term hearing aid full-time users and non-users. Categorical loudness scaling using pure-tone stimuli was carried out by hearing-impaired subjects. The mean levels of loudness categories at one frequency (hearing threshold: 50-75 dB HL) in a group of 18 hearing aid users (daily use < or = 15 hours per day) were compared with the corresponding levels found in 18 hearing-impaired non-users with the same distribution of hearing thresholds. The results show that, for hearing losses of 50-75 dB HL, the mean level rated as 'loud' by long-term full-time users of hearing aids is 4.5 dB above the mean level of the corresponding category rated by non-users. This difference is statistically significant (P<0.05). No significant differences were found for the lower categories. Among those subjects who had been wearing hearing aids for at least six months, no significant correlation was found between the levels of the 'loud' category and the length of time that hearing aids had been used.

Long-term test-retest reliability of category loudness scaling in normal-hearing subjects using pure-tone stimuli

The present study investigates the test-retest reliability of category loudness scaling with pure tones for each of the scaling categories: 'very soft', 'soft', 'OK', 'loud', 'very loud' and 'too loud' at the audiometric frequencies 0.5, 1 kHz, 2 kHz and 4 kHz. Category loudness scaling at two sessions separated by between 1 and 4 weeks was obtained from 16 normal-hearing subjects who all had normal otoscopy, present acoustic reflexes at audiometric frequencies 0.5-4 kHz and middle ear pressure within +/-50 daPa. Intra-subject between-session reliability was found not to be frequency dependent, and comparison with other studies revealed that reliability is not dependent on the applied stimulus signal. Test-retest reliability varied between the different categories: In the categories 'very soft', 'loud', 'very loud' and 'too loud' the test reliability is in the same range as found for hearing thresholds determination, whereas for the 'soft' and 'OK' categories it is poorer. The greater uncertainty for intermediate levels should be considered when using category loudness scaling, e.g. for calculating hearing aid parameters.

[TSH-receptor blocking antibodies in juvenile thyrotoxicosis]

The case presented is a 12 year-old girl with hyperthyroidism due to juvenile Grave's disease, who during the course of treatment developed hypothyroidism due to TSH-receptor blocking antibodies, measured by bioassay. The bioassay used was performed on CHO-R cells measuring c-AMP. The role of radioreceptor assays and bioassays in measuring TSH receptor antibodies in hyper- and hypothyroid Graves' disease in discussed.

The influence of spontaneous otoacoustic emissions on the amplitude of transient-evoked emissions

The aim of the study was to analyse whether the presence of spontaneous otoacoustic emissions (SOAEs) in a group of normal-hearing adults is related to larger transient evoked otoacoustic emission (TEOAE) amplitudes when compared to a similar adult population without SOAEs. Twenty-four normal-hearing subjects participated in the investigation. They were selected to form two groups of 12, one containing only subjects with measurable spontaneous emissions, the other of members who had no measurable spontaneous emissions. Each group comprised 7 males and 5 females. TEOAEs were recorded in both linear and non-linear mode, and equivalent sound pressure levels in different octave frequency bands were calculated. For each frequency band, the comparison of the equivalent sound pressure levels in the two selected groups showed statistically significant differences. Therefore, when normative TEOAE data were collected with the purpose of establishing a normative reference for the assessment of cochlear hearing loss, it is mandatory to search for and, when pertinent, to compensate for the presence of SOAEs.

[Agenesis of the corpus callosum]

This article presents ten children with agenesis of the corpus callosum diagnosed during the period 1978-1992. The children were re-examined in 1992, and the results of the examination compared with the results of other authors. Among the ten children, five had other cerebral anomalies, six had eye anomalies, six were mentally retarded and two suffered from epilepsy. There was one boy with inversion on chromosome no. 1, one girl with Aicardie's syndrome, two sisters with agenesis of the corpus callosum (ACC), one of whom was suffering from diabetes insipidus, and two brothers with Walker Warburg's syndrome. ACC is often associated with mental retardation, epilepsy and eye anomalies and may be found associated to many different syndromes.

Calibration of ipsilateral stimulus transducer for acoustic reflex measurements

Pure-tone Reference Equivalent Threshold Sound Pressure Level (RETSPL) of the ipsilateral stimulus receiver for acoustic reflex measurements on Madsen Electronics type Zodiac 901 impedance audiometer is provided. The results, obtained from 20 normal-hearing subjects, are achieved by comparing hearing threshold levels measured using a TDH 39 telephone (calibrated to ISO 389) with thresholds recorded using the ipsilateral stimulus insert phone. The calibration is referenced to an IEC-711 ear simulator and comprises the following frequencies: 125, 250, 500, 750, 1000, 1500, 2000, 3000, 4000, 6000, 8000 Hz.

[Disposable transducers for invasive blood pressure measurement. A test of the dynamic characteristics]

The accuracy of intra-arterial blood pressure measurement is dependent on the dynamic characteristics of the transducer. Specifications made by the manufacturers are often misleading. Four different transducers are tested in a clinically relevant setting. The resonance frequencies of all the transducers were found to be acceptable.

[Invasive blood pressure measurements. Factual safety]

Intra-arterial blood pressure measurement is often used in patients with unstable haemodynamics. The demand for accuracy in such measurements is high. Usually these demands are fulfilled, but situations can occur where the dynamic characteristics of the system are exceeded. In order to acknowledge this situation, one must be aware of these dynamic characteristics. The significance of the system's resonance frequency and damping is described. A method to control the usability of the system is described.

[Keloid of the external ear]

Keloid formation is an unpredictable complication to normal scar tissue development. The etiology is unknown, although an individual predisposition may be present. There is a regional propensity for the head, neck and upper torso. The treatment is difficult, and this should be taken into consideration when cosmetic procedures are being contemplated. This type of surgery should be avoided in individuals with previous keloid formation. Four cases of keloid formation, two after ear lobe piercing and two after otoplasty are presented and a satisfying outcome of surgical revision with ensuing steroid medication is reported.

Growth of distortion product otoacoustic emissions with primary-tone level in humans

This study addressed the hypotheses that the growth of the level of distortion product otoacoustic emissions (LDP) with primary-tone level reflects the behavior of a third-order nonlinear polynomial system, and that two sources exist for these distortion products. The results indicated that the 2f1-f2 otoacoustic emission in humans can be measured over a much larger stimulus range than reported previously, even for stimuli (L1 = L2) as low as 10 dB SPL (re 20 microPa). The input/output functions are best described as a straight line with a rate of growth of about 1 dB/dB of stimulus level. For stimulus levels at which metabolically active, nonlinear cochlear processes are in operation, the system does not behave as a simple third-order nonlinear polynomial. Small plateaus and sharp discontinuities or 'notches' can occur in the functions at stimulus levels of approximately 55 dB SPL. These characteristics are consistent with the notion of two separate sources of the LDP, one at low stimulus levels, and one at high levels. An alternative explanation is that the measured otoacoustic emission does not represent only the activity at a single location along the basilar membrane but includes the effects of interactions among similar signals arising from multiple locations, or from the original source via multiple paths.

Clinical significance of probe-tone frequency ratio on distortion product otoacoustic emissions

Parametric variations in the ratio of primary-tone frequencies were explored to optimize the amplitude of the 2f1-f2 distortion product otoacoustic emission for clinical purposes. Ten ears from 5 normally hearing human subjects were examined with primary tones geometrically centred around the standard audiometric frequencies of 0.5, 1, 1.5, 2, 3, 4, 6 and 8 kHz. The distortion product at the frequency 2f1-f2 (f1 < f2) was measured at six probe tone frequency ratios (f2:f1) varying between 1.15 and 1.40 using equal level primaries of 75 dB SPL. The results showed that a single f2:f1 ratio between 1.20 and 1.25 provides a reasonable value for clinical use in that it optimizes the magnitude of the distortion product at 2f1-f2, provides for sufficient resolution in the test frequency range, and is applicable to the standard clinical test frequencies.

Clinical significance of relative probe-tone levels on distortion product otoacoustic emissions

The effect of systematic variations in the relative levels (L1, L2) of two primary tones (f1, f2) on the amplitude of the distortion product otoacoustic emission (DPOAE) at 2f1-f2 and f1 < f2 was investigated in 14 ears from 7 normally hearing human subjects. The primary tones (f2:f1 = 1.23) were geometrically centred at the standard clinical frequencies of 0.5, 1, 1.5, 2, 3, 4, 6 and 8 kHz. The quantity L1-L2 was varied systematically from -10 dB through + 10 dB with L2 held constant at 75 dB SPL for negative values, L1 held constant at 75 dB SPL for positive values, and L1 = L2 = 75 dB SPL at 0 dB relative difference. The maximum amplitudes of the distortion products were generated when L1 = L2 at all geometric centre frequencies except 8 kHz. The reduction of the DPOAE with reduction of L1 was linear at a rate that gradually increased as a function of geometric mean frequency. To a lesser extent, the reduction of the DPOAE with reduction of L2 also was linear but at a rate that systematically decreased as a function of geometric mean frequency. The results suggest, that to maximize the level of the distortion product for clinical purposes, the relative levels of the primary tones should be equal to each other, at least when overall stimulus levels are around 75 dB SPL and f2:f1 = 1.23.

Distortion product otoacoustic emissions. The influence of the middle ear transmission

Distortion product otoacoustic emissions (DPOEs) were recorded in 8 normal hearing subjects (16 ears, mean age 37) in order to evaluate the sensitivity of the DPOE amplitudes as a function of pneumatic changes (-400 to +200 daPa) in the external ear canal. The responses were collected using time averaging and subsequent FFT-analysis of the collected data. Distortion products were measured at the following geometric mean frequencies: 1,000, 2,000, 4,000, 6,000 and 8,000 Hz. The results show that the amplitudes of the distortion products depend on an optimal transmission through the middle ear, and that measurements of DPOEs should always be preceded by determination of the middle ear pressure. The present findings are in good agreement with investigations based on evoked otoacoustic emissions published by other researchers.

Keloids of the external ear

Keloid formation is a rare complication of normal scar tissue development, also to the surgeon who performs surgery on the external ear. We are presenting 4 cases of keloid formation which occurred after ear piercing in 2 cases and after otoplasty in another 2 cases. The treatment of keloid formation caused difficulties and is not unequivocal. Therefore we wish to present our experiences as we have seen no cases of keloid formation after otoplasty described in the literature.

Inverted papilloma of the nasal cavity: pathological aspects in a follow-up study

The initially removed tumors from 42 patients with inverted papillomas of the nasal cavity and paranasal sinuses were subjected to an extensive histopathological examination in order to define the characteristics associated with multiple recurrences and development of malignancy. Two of the patients subsequently developed squamous cell carcinoma and eight patients had more than one recurrence. No specific histological characteristic was determined to be a predictor of multiple recurrences or development of malignancy. However, three patterns of characteristics emerged from the data which were found to be related to the development of malignancy, multiple recurrences, and benign behaviour. Malignancy was found to be associated with bilateral inverted papilloma, a predominance of mature squamous epithelium, the presence of all three epithelial types (metaplastic squamous, mature squamous, and cylindrical), severe hyperkeratosis, a mitotic index greater than or equal to 2 per high-power field (HPF), absence of inflammatory polyps among the papillomas, an abundance of plasma cells, and an absence of neutrophils. Multiple recurrences (without malignancy) were associated with a mitotic index greater than or equal to 2 per HPF and an absence of inflammatory polyps. Benign behaviour was associated with predominantly mucinous tumors, a mitotic index less than 1 per HPF, a ratio of neoplastic epithelium/connective tissue stroma greater than or equal to 6, and the presence of inflammatory polyps among the papillomas.

Fibre-optic bronchoscopic evaluation of tracheal tube position

Verification of tracheal tube position by fibre-optic bronchoscopy was evaluated in 20 critically ill adult patients. The distance between the carina and the tube was measured by direct visualization with a fibre-optic bronchoscope and compared with the corresponding measurement obtained from a concomitant chest radiograph. The measured values did not differ significantly and in 18 out of 20 patients the accuracy was within 2 cm. No adverse effects were observed. We conclude that verification of tracheal tube position by fibre-optic bronchoscopy is a safe alternative to chest X-ray.

Drugs and femoral neck fracture: a case-control study

Two hundred consecutive patients with femoral neck fractures (FNF) and 200 controls matched by age, sex, nursing home residency and number of admissions within the last 2 years, were interviewed about recent drug use. The matching criteria were chosen to achieve case and control groups that were comparable with regard to overall physical disability. Thus a preliminary study had shown FNF to be strongly associated with nursing home residency and to be correlated with the number of recent hospital admissions. FNF was found to be negatively associated with use of coronary drugs (OR = 0.27; 95% CI = 0.11-0.70) and positively associated with drug use in general (OR = 2.00; 95% CI = 1.04-3.05). The OR for the various classes of psychotropic drugs was consistently greater than 1., although this was not statistically significant. An inherent problem in interpreting such findings is that underlying disease may predispose the subject to both FNF and drug use, thus creating a non-causal relationship.

[Use of ketanserin in anesthesia. A selective S2 serotonin receptor antagonist]

Serotonin is a vasoactive amine. It is formed in the chromaffin cells in the small intestine and is inactivated in the liver and lungs. The remainder is taken up in the thrombocytes so that only minimal quantities are found free in the plasma. The peripheral effect of serotonin occurs probably exclusively by means of a release of amine from the thrombocytes following local aggregation of these. Serotonin is thought to play a pathogenetic role in both systemic and pulmonary hypertension. Ketanserin is a serotonin antagonist with alpha-blocking effect. It reduces the blood pressure by reducing the peripheral vascular resistance without causing reflex tachycardia or fall in the minute volume of the heart. In the field of anaesthesiology, it may be employed in per- and postoperative hypertension but on account of the peripheral vasodilating effect it may also be employed in other conditions with peripheral vasoconstriction. Ketanserin has a moderate effect in cases of acutely developed pulmonary hypertension.

[The use of urapidil in anaesthesia. A selective S1A-serotonin receptor antagonist with antihypertensive action]

Serotonin is a vasoactive amine which is considered to play a pathogenetic role in systemic hypertension on account of the peripharal vasotonic effect of serotonin. The central serotoninergic neurones excitatory influence of the sympathetic tone may, however, be a contributory cause. Urapidil is a selective S1-serotonic receptor-agonist with alpha-blocking effect. This is considered to influence the presynaptic receptors of the serotoninergic neurones and thus to inhibit the excitatory influence on the sympathetic system. It reduces the blood pressure by reducing the peripheral vascular resistance without simultaneous provocation of reflex tachycardia or reduction in the minute volume of the heart. In anaesthesiology, this may be employed for perioperative hypertension. The preparation appears to be particularly useful in neuroanaesthesia as in contrast to other antihypertensive agents, it does not appear to alter the intracranial pressure.

Comparison of anatomical location of squamous cell carcinoma within the oral cavity and oropharynx with the incidence of in vitro hyperdiploidy

The anatomical location of the squamous cell carcinoma (SCCA) within the oral cavity and oropharynx influenced the association of SCCA with the biomarker in vitro hyperdiploidy in human dermal fibroblast cultures (IVH). There was a strong association of IVH with the occurrence of SCCA in the anterior 2/3 of the tongue, floor of the mouth and lower alveolar ridge of the oral cavity and in the base of the tongue and pharyngeal wall of the oropharynx. There was a lower association of SCCA with IVH in the tonsillar region of the oropharynx. IVH showed no association with SCCA located in other anatomical parts of the oral region. The patient group whose diagnosis of SCCA in the anterior 2/3 of the tongue occurred prior to the age of 50 years were invariably IVH-, whereas those diagnosed after the age of 50 years were IVH+, providing evidence for heterogeneity. There was no such correlation of biomarker subgrouping with age of diagnosis demonstrated for SCCA at any other anatomical location within the oral cavity or oropharynx.

Radiologic aspects of inverted papilloma

A series of 42 patients with inverted papilloma is presented. Of these, 38 patients had radiologic examinations. Thirty patients had comparable radiologic examinations in the form of X-ray of the sinuses and/or tomography and/or CT scan. The preoperative findings were compared and related to the extent of the tumor at surgery. Clinical examination combined with CT appears to be the optimal preoperative procedure. Follow-up should include CT in order to allow comparison with postoperative status and, preferably, also with preoperative radiologic findings.

[Inverted papilloma of the nose and nasal sinuses. Incidence, long-term course, therapeutic results]

Inverted papilloma is an unusual tumour in the nose and nasal sinuses with a marked tendency to recurrence following surgical treatment and with a greatly increased risk for synchronous or metachronous development of carcinoma. A retrospective investigation comprising 42 patients with histological revision revealed an incidence of 0.6/100,000 per annum. Two patients had also carcinomata. No significant differences were observed between the recurrence rates following simple excision, excision via the maxillary sinus or via lateral rhinotomy. Follow-up control for ten years is recommended.

Inverted papilloma: a follow-up study including primarily unacknowledged cases

Inverted papillomas (IPs) in the nose or the paranasal sinuses exhibit a tendency for rapid growth with bone destruction, a high recurrence rate, and an association with malignancy, requiring early diagnosis and aggressive surgical therapy. A number of operative approaches have been reported in the literature, with greatly varying results. Furthermore, the incidence of IP and the association with carcinoma are not well-established. In this study, we present a series of 42 patients with IP. Drawing from the resources of two institutes of pathology, we reviewed all specimens of nasal cavity or paranasal sinus tissue taken between the years 1975 and 1986, and performed a thorough follow-up of all IP patients. The incidence was found to be 0.6 cases per 100,000 inhabitants per year in a well-defined representative geographic region. Two patients had concomitant carcinoma. When the initial surgical approach was lateral rhinotomy, the recurrence rate was 50%. This was not significantly different from that noted following excision through a sinusectomy (62%) or simple endonasal excision (43%). However, initial procedures were selected individually, mainly on the basis of tumor size and location. Accordingly, a limited procedure is considered justified even in cases with lateral lesions, if the tumor is sufficiently visible and confined. In other cases, lateral rhinotomy is required. Septal IPs are often detected at an early stage and are therefore often amenable to local excision.

Runaway pacemaker: a still existing complication and therapeutic guidelines

Runaway pacemaker is a rare, but still existing potential lethal complication in permanent pacemakers. Within 4 1/2 years, we saw two cases of runaway pacemaker in patients with multiprogrammable, VVI pacemakers (Siemens-Elema, Model 668). In both cases a pacemaker-induced ventricular tachycardia (rate 240-260 beats/min) was documented. One patient died. Runaway pacemakers must be exchanged as soon as possible. Until this can be accomplished, different emergency maneuvers should be tried. As documented in the cases presented, placing a magnet over the pacemaker may result in a lower, more physiological pacing rate. Reprogramming the pulse generator to a lower output or the use of external chest wall overdrive stimulation may also be successful, but these procedures require the presence of an adequate escape rhythm. If this is not the case or the former maneuvers have failed, an external pacemaker may be connected to the permanent pacing lead. Thereafter, the lead can be safely cut. As an alternative, a temporary transvenous pacing lead may be established prior to disconnecting the permanent pacing lead.

Maximum ultrafiltration rates during peritoneal dialysis in rats

It has been suggested that filtration pressure equilibrium could occur in peritoneal capillaries during peritoneal dialysis with very hypertonic exchanges. Rats were exposed to peritoneal dialysis solutions using 16 ml instillations, 30 minute cycles, and dextrose concentrations from 1.4 to 20 g%. There was a plateau in ultrafiltration per exchange at mean osmotic gradients above 360 mOsm/kg H2O near 12.5 ml/ex (0.42 ml/min). The findings are also compatible with filtration pressure equilibrium predictions at an effective capillary plasma flow of 0.84 ml/min and a filtration fraction near 50%. Studies with cardiovascular drugs (norepinephrine i.v., nitroprusside i.p., and dobutamine i.v.) showed no effects on the maximum ultrafiltration rates. This might indicate that flow is rather fixed because of known microcirculatory effects of solutions themselves.

Injury to developing canines as a complication of intranasal antrostomy. Report of a case

A case is presented in which a 7-year-old boy had an intranasal antrostomy made, during which operation both developing permanent canines were injured. Despite complete resection of the roots, both canines erupted normally, supporting recent experimental studies of the eruption mechanism which suggested the importance of the tooth follicle instead of root growth as the essential mechanism for tooth eruption. Methods to prevent damage to permanent tooth germs during intranasal osteotomy are described.

Cytological events in allo-stimulated lymphocytes triggered by exposure to alloantigens. V. Response to disrupted target cells

H-2b lymphocytes sensitized against H-2d alloantigens or H-2k alloantigens were triggered by incubation with disrupted or intact H-2d target cells. The triggering of the lymphoid cells was stopped by fixation with glutaraldehyde. Changes in cell size, in numerical density of the endoplasmic reticulum (ER), and the Golgi apparatus (GA) as well as in the areal density of the lysosomes and the mitochondria in the lymphoblasts during the first three hours of triggering were measured with a Hewlett Packard digitizer. No significant changes in cell size or in the density of GA, lysosomes and mitochondria were observed after triggering with disrupted target cells, but a significant increase in the density of ER occurred in the lymphoblasts previously stimulated against the target cell. After triggering with intact target cells, cell size of the lymphoblasts increased, as well as the density of GA, mitochondria and lysosomes while the density of ER exhibited a decrease followed by an increase. The disrupted target cells were shown to inhibit the release of 51Cr during lysis of 51Cr-labelled target cells.

Cytological events in allo-stimulated lymphocytes triggered by exposure to stimulatory alloantigens. IV. The influence of prednisolone

H-2b lymphocytes were sensitized against H-2d alloantigens by mixed lymphocyte culture reaction (MLR) and incubated with H-2d target cells in the presence of prednisolone or without prednisolone (control). The interaction between lymphoid cells and target cells was stopped by fixation with glutaraldehyde. Changes in cell size, in numerical density of the end of plasmic reticulum (ER) and the Golgi apparatus (GA) as well as in areal density of the lysosomes and the mitochondria in the Golgi apparatus (GA) as well as in areal density of the lysosomes and the mitochondria in the lymphoblasts during the first four hours of interaction with target cells were measured with a Hewlett Packard digitizer. The cell size showed no significant change within the first hour of interaction with target cells, but during the second hour a minor increase in cell diameter was observed whereas the diameter of the control lymphocytes increased a great deal during the first half hour as well as from the second to the third hour. The numerical density of the ER decreased throughout the four hour observation period, whereas the control lymphocytes exhibited a decrease in the numerical density of ER within the first hour after which the density increased. During the first hour of interaction with target cells the numerical density of the GA decreased and there was no increase during the rest of the observation period, whereas in the control lymphocytes the density of GA increased from the second to the third hour of interaction with target cells. There was no lysosome formation, and no significant change in the areal density of mitochondria during the four hour observation period, whereas the density of lysosomes as well as mitochondria increased in the control lymphocytes.

Cytological events in allo-stimulated lymphocytes triggered by exposure to stimulatory alloantigens. III. Changes in the areal density of cytoplasmic vacuoles containing endocytized Thorotrast

H-2b lymphocytes were sensitized against H-2d alloantigens by a lymphocyte culture reaction (MLR) and incubated with H-2d mastocytoma cells. Thirty minutes before incubation with the mastocytoma cells Thorotrast was added to the lymphocyte culture medium. The interaction between lymphoid cells and mastocytoma cells was stopped by fixation with glutaraldehyde. The areal densities of the cytoplasmic vacuoles were examined by electron microscopy. Two populations of lymphocytes were observed, small lymphocytes with heterochromatic nuclei and larger lymphocytes (lymphoblasts) with euchromatic nuclei. Only the lymphoblasts showed changes following interaction with target cells. The areal density of Thorotrast containing vacuoles in sensitized lymphoblasts increased during the three hour observation period, but the percentage of vacuoles containing Thorotrast in the total area of cytoplasmic vacuoles decreased in the first thirty minutes of interaction with target cells. This observation may indicate greater formation of vacuoles from the Golgi apparatus compared with the formation of vacuoles from the cytoplasmic membrane at the onset of interaction with target cells. In the multivesicular bodies (MVB) the Thorotrast was first observed inside the small vesicles and later on it was also observed in the matrix of the MVB. After three hours of interaction Thorotrast was observed laying "free" in the matrix of phagosomes along with myelin figures.