MR imaging-guided muscle biopsy for correlation of increased signal intensity with ultrastructural change and delayed-onset muscle soreness after exercise.

To determine if there is a correlation between the degree of delayed increase in signal intensity (SI) of muscle after exercise on magnetic resonance (MR) images and the amount of ultrastructural (ULS) injury and delayed-onset muscle soreness (DOMS), MR imaging-guided muscle biopsy was performed to obtain tissue from the legs of nine sedentary subjects 48 hours after downhill running on a treadmill. The degree of soreness was subjectively graded. T1-weighted, spin-density, T2-weighted, and short inversion time inversion-recovery images were obtained before and after biopsy, at 48 and 96 hours after exercise, respectively. The delayed SI increase of muscle on images obtained before biopsy was subjectively graded and measured. The degree of ULS injury was determined with electron micrographs. Serum creatine kinase levels were obtained before and up to 144 hours after exercise at 24-hour intervals. The measured SI, SI grades, and DOMS grades were correlated with the degree of ULS injury. Linear regression analysis revealed poor correlation between the DOMS grades and the degree of ULS injury and good correlation between the SI grade and the degree of ULS injury.


Measurement of CT section thickness by using the partial volume effect.

A method to calculate section thickness from mean computed tomographic (CT) numbers of two materials in a section (and by varying the ratio of their volume) was developed. A cylindrical water phantom with an acrylic rod at the center was used, and section thickness was measured with two CT scanners. At actual section thicknesses of more than 4 mm, results with this method differed from results of the aluminum ramp method by only about 10%. At section thicknesses of 1-2 mm, however, the difference was about 30%-50%. Measurement with this method was not influenced by filter function and therefore was more accurate than with the aluminum ramp method.


Template-guided breast US.

The authors modified a standard breast compression plate to allow ultrasound (US) scanning to be performed in the longitudinal and transverse directions with the breast positioned craniocaudally or laterally in a mammographic unit. The technique allows quick mammographic-US correlation of lesions, characterization of lesions as cystic, solid, or indeterminate, and the ability (with coordinates marked on the plate) to proceed directly with aspiration of sonographically indeterminate lesions.


Wallstent metallic biliary endoprosthesis: MR imaging characteristics.

Image quality and safety of magnetic resonance (MR) imaging were evaluated in vitro and in eight patients with the most commonly employed metallic biliary endoprosthesis. In vitro, the stent produced no tip deflection at 0.6 or 1.5 T. Trace magnetic susceptibility artifact, similar to artifact from a column of air, paralleled the stent. In patients, image degradation was minimal with conventional pulse sequences. Middle-field-strength spin-echo images revealed minimal artifacts indistinguishable from those produced by pneumobilia.


[Nationalism, hatred of foreigners and antisemitism. Psychoanalytic considerations].

Widespread social crisis phenomena such as unemployment, shortage of housing or lack of prospects are not sufficient to explain aggressive nationalism and the revival of xenophobia in present-day Germany. While from a psychoanalytic viewpoint xenophobia and anti-Semitism have been extensively examined, the same can by no means be said of the phantasm of the "nation". With reference to a case study, the author demonstrates that the adoption of nationalist ideologies (which in Germany specifically are very much bound up with the traditional notion of the nation as a biological organism) can serve both to prevent the outbreak of neurosis at the individual level and to effect what Freud called the "spurious" healing of existing neuroses. Psychologically speaking, the phantasm of the "nation" provides scope for the realization of the desire for pre-ambivalent fusion with an object that has rid itself of everything heterogeneous, alien and autonomous.


[Hatred of foreigners and purity--current aspects of an illusion. Social psychological and psychoanalytic considerations].

This study draws upon both Carlo Ginzburg's procedures for establishing and preserving (historical) evidence and Claude Lévi-Strauss' structuralist approach with its analysis of "primitive" mythologies to demonstrate that binary coding of the social domain is an all-pervasive structural principle. Heim's intention in this is to show that (present-day) xenophobia and racism are the products of a phantasm centering around the division of the world into pure and impure. The author brings into alignment collective fantasies about the homogeneity of the "body politic" with a form of primary narcissism which, if it is to preserve the illusion of original purity, is forced to externalize instinctual urges experienced as heterogeneous and unpleasurable and project them onto "foreigners" and things foreign.


[Native and alien. On ethnic identity].

Freud's theory of the antagonism between family and culture provides the point of departure for this study, which sets out to rehabilitate the concepts "ethnic" and "ethnic identity". The family represents the locus of established tradition and familiar ritual and seeks to make each new generation identify with "us and ours". Culture, by contrast, is dependent on contact and confrontation with things alien and foreign. Between these extremes and the potential dangers specific to each of them, ethnicity--which is neither biological nor cultural--represents a mediating factor. In adolescence, a phase of dis- and re-orientation, the individual needs to draw upon his ethnic identity to reconcile the disturbing contradiction between familial and cultural claims, between the native and the alien.


["Proud of violence". Psychoanalytic remarks on adolescence and right extremism].

Young people with extremist right-wing leanings who join together to form gangs frequently come from a social background which has had a traumatic influence on their biographies from an early stage. The right-wing radical group functions as a substitute for caring parents and other figures that these youngsters can look up to. Within these constellations they then act out the violence that they themselves have been the victims of. The author points out that, both on an individual and social plane, these young people stand for facets of our own selves that we have severed off or negated and conflicts which we have yet to come to terms with.


MR imaging of late radiation brain injury.

One hundred and four patients treated with radiotherapy for intracranial tumors and their related conditions were reviewed to evaluate the usefulness of magnetic resonance (MR) imaging in demonstrating increased signal intensity areas on T2-weighted images that were considered to be late adverse effects of irradiation of the brain. High signal intensity areas of the white matter were divided into five patterns according to their size and extension. Severity was found to increase with age and irradiation doses of more than 50 Gy. In patients with irradiation doses of more than 60 Gy, the severity of increased with shorter interval after radiotherapy than in those given low irradiation doses. Clinical findings such as mental deterioration, motor abnormality, and visual defect were observed in 12 patients. These findings were closely correlated with the severity of the MR pattern. In most patients, high signal intensity areas were stable or progressive during the course of follow-up. However, these areas were regressive in three patients. Imaging with Gd-DTPA was performed in 36 patients, six of whom showed enhancement. Pathological findings on enhancement included astrocyte proliferation and coalescing vacuoles in neural tissue. MR imaging is an excellent method with which to monitor the adverse effects of radiotherapy of the brain.


MR Gd-DTPA enhancement of radiation brain injury.

MR examinations of 104 patients who had undergone radiotherapy to the brain were reviewed. Thirty-six patients received Gd-DTPA enhanced study during the course of MR evaluation and six of the patients showed enhancing radiation necrosis. Histopathological confirmations were obtained in three patients. Gd-DTPA enhancing radiation lesions were multiple and patchy in three patients, multiple and patchy with cyst formation in two and ring shaped in one. In terms of their distribution, enhancing lesions in four patients were seen only in the white matter within the irradiated field and these patients had undergone radiotherapy within five years. The interval after radiotherapy was more than eight years in two patients and their enhanced lesions were observed in both the white and gray matter. Histopathological findings of Gd-DTPA enhancing radiation necrosis were gliosis and coalescing vacuoles of the neural tissue. None of these enhanced radiation lesions showed significant mass effects. Patterns of the enhancement were not specific. It was considered to be difficult to differentiate tumor recurrence from radiation necrosis with conventional Gd-DTPA enhanced MR examinations. In one patient, delayed MR images after Gd-DTPA administration showed increases in the size and number of radiation enhanced lesions. Dynamic and delayed MR study might add more information to conventional imaging after Gd-DTPA. Further studies are necessary to differentiate radiation lesions from tumor recurrences.


Intraluminal irradiation for T2M0 esophageal cancer: effect of patient selection on prognosis.

The contribution of intraluminal irradiation to the prognosis of T2M0 esophageal cancer was examined with reference to patient selection. To determine the effect of patient selection, we used esophagrams to assess the potential difficulty of inserting a tube for intraluminal irradiation in 39 patients who were treated with external irradiation prior to 1982. Twenty-two patients were assessed as likely to have been able to undergo intraluminal irradiation (group 1) while 17 were assessed as unlikely to have been able to undergo the procedure (group 2). Of 36 patients treated after 1983, 19 patients were treated with a combination of intraluminal irradiation and external beam therapy (group 3) and 17 by external irradiation alone (group 4). The median survival times of groups 1, 2, 3, and 4 were 10.8, 6.4, 12.0, and 8.5 months, respectively. The prognosis of patients treated with combination therapy (group 3) was superior to that of those treated before 1982 (groups 1 + 2). However, there was no improvement in the prognosis of T2M0 esophageal cancer treated by radiotherapy after the introduction of intraluminal irradiation, and the difference between the survival curves of patients treated by combination therapy (group 3) and with a wide esophageal lumen (group 1) was not significant. Our study thus showed that the selection of patients according to the insertability of the intraluminal therapy tube affected the prognosis.


MR imaging in uterine cervical cancer after radiotherapy.

The usefulness of MR imaging (MRI) in uterine cervical cancer after radiotherapy was evaluated in 18 patients. MRI was performed before and within one month after radiotherapy. In eight patients the uterus assumed a nearly normal appearance with resolution of the tumor on MRI. In another eight patients the tumors resolved, but an area of high signal intensity remained at the cervix. In these patients the tumors were well controlled at clinical examinations and during the mean follow-up period of 15-18 months. Therefore a persistent area of high signal intensity alone at the cervix on MRI is not itself indicative of residual tumor. An area of high signal intensity and a residual cervical mass persisted in two cases, and they were histologically proven to be due to residual tumor. Both patients died of recurrent disease at seven and 11 months after their radiotherapy. We conclude that MRI is useful for evaluating patients with cervical cancer at the completion of radiotherapy, and that MRI complements conventional clinical examinations.


Psychosocial outcome six months after heart transplant surgery: a preliminary report.

With improvement in survival of patients treated with heart transplant, evaluation of recovery with respect to psychosocial function has become an important issue. In this study, psychosocial functioning of 44 heart transplant recipients pretransplant was compared to their functioning 6 months posttransplant. Before transplantation, patients experienced considerable psychosocial distress attributable to illness. At 6 months after transplantation, the majority of patients showed significant improvement in emotional, domestic, sexual, social, and vocational functioning. However, 25% of patients showed deterioration in psychosocial adjustment and 11% showed an increase in mood disturbance. Further effort is indicated to improve psychosocial outcome of heart transplantation.


Digital angiography using hand-operated table movement for vascular disease of the pelvis and lower extremities.

We developed a new technique using hand-operated table movement during digital angiography (DA) for the study of vascular disease of the pelvis and lower extremities. Digital video memory (DVM) is used in this technique to digitize, record, and display fluorographic images without subtraction in real time. This allows free table movement and the imaging of a large area with a single injection of contrast medium. Forty-five examinations for vascular disease of the pelvis and lower extremities were performed by this DA technique. Good images of an extensive area from the lower abdomen to the lower leg were obtained in a single study.


Holistic health patterning in multiple sclerosis.

Multidimensional health patterning of three groups of persons with multiple sclerosis (MS) was examined. Changing patterns over a 5-year period for each group also were examined. Serial self-assessments of the subjects' prevalence of MS-related symptoms (motor, brainstem, sensory, elimination, mental-emotional) and level of ADL functioning (fine and gross motor activities, sensory/communication, socializing/recreation, intimacy) were obtained by mail. The number of subjects grouped by years since diagnosis was: 69 (0-5), 49 (greater than 5-10), and 93 (greater than 10). Study findings indicated significantly higher levels of functioning in areas of fine and gross motor activities and intimacy among the more recently diagnosed group but no difference among the groups for sensory/communication, recreation/socializing, and symptoms. Significant increases in motor and brainstem symptoms and decline in fine and gross motor activities and intimacy occurred over the 5-year period particularly for the 0 to 5 year postdiagnosis group. Knowledge of symptom and ADL patterning is essential for nurses and other health care providers in anticipating the concerns and needed services of persons with MS and their families.


Interactions of parents and nurses with high-risk preterm infants.

The interactions of preterm infants with parents were compared with their interactions with nurses. Twenty-nine high-risk preterm infants who were a part of a larger longitudinal study of behavioral development were observed once weekly from 7 p.m. to 11 p.m. A single observation for each infant that contained a minimum of 2 min of parental care and 2 min of nursing care was selected for analysis. Results showed that nurses and parents provided different types of stimulation with nurses more likely to engage in procedural care and parents more likely to hold, talk to, move, and touch the infants affectionately. Infants showed more sleep-wake transition, large body movements, and jitters when with nurses and more active sleep and more smiles when with parents. Similar differences were found when parents and nurses were just holding or touching the infants, but no differences in infant responses were seen during feeding or changing. Thus, the different infant behavioral responses appeared to result primarily from the different stimulation provided by parents and nurses. Implications of these findings for research and clinical practice are discussed.


Asymmetrical FDG-PET and MRI findings of striatonigral system in multiple system atrophy with hemiparkinsonism.

The asymmetry of the local cerebral metabolic rate for glucose (lCMRglc) and magnetic resonance (MR) imaging was studied in five patients with multiple system atrophy (MSA) presenting hemiparkinsonism. lCMRglc was measured with 18F-2-fluoro-2-deoxy-D-glucose and positron emission tomography (PET) in these patients and five normal control subjects. MR images were obtained in five patients and 11 control subjects. In all patients, T2-weighted MR images showed hypointense areas in the posterior lateral putamen. They were bigger or lower in intensity on the contralateral side than on the ipsilateral side. Significant glucose hypometabolism was found in the posterior putamen on the contralateral side to hemiparkinsonism. A significant decrease in size was found in the contralateral putamen, caudate nucleus, and pars compacta of the substantia nigra. However, no significant correlation was seen between PET and MRI data. In the control subjects, no apparent asymmetry was observed. PET and MR imaging demonstrated the characteristic asymmetry corresponding to the pathological findings reported in MSA.


Adolescent stress and coping: a longitudinal study.

The purpose of this longitudinal panel study was to investigate developmental and gender influences on stress and coping in adolescents attending a suburban high school in Tennessee. Data were collected from the same 167 subjects during the freshman year and again during the senior year. Life events stress was measured through the Adolescent Life Change Event Scale (ALCES) and ways of coping were categorized from data gathered from an open-ended questionnaire. Girls reported more life events stress at both testings than boys. Life events stress was greater at senior testing for both girls and boys, but girls' scores increased more. The "gender intensification" phenomenon may account for the greater disparity in types of stress reported by boys and girls as seniors. Girls generally reported more life events associated with interpersonal and family relationships. Both girls and boys reported coping with stress mostly through active distraction techniques such as exercise. However, girls' use of active distraction decreased over time, while passive distraction increased. Self-destructive and aggressive coping behaviors increased for boys. There were no relationships between amounts or types of life events stress and ways of coping for subjects at either time.


Carbon-13 chemical shift imaging of [1-13C] glucose under metabolism in the rat head in vivo.

Carbon-13 chemical shift images (metabolic maps) of [1-13C] glucose in the heads of rats were obtained and compared with proton images of the same rats in terms of signal allocation. Wistar rats were kept awake or anesthetized. [1-13C] glucose was injected intravenously in a dose of 1 g per kg of body weight. The head of the Wistar rat was placed on or into circular coils. Carbon-13 images were obtained using a 7.05 Tesla system. A simple spin echo sequence was used with a chemical shift selective (CHESS) pulse. The frequency band width was set to cover the spectral breadth of the carbon-13 signal of [1-13C] glucose. The slice thickness of the image was 4 mm or 6 mm, and the field of view (FOV) was 60 mm x 60 mm, with a matrix size of 64 x 64. The total acquisition time was 36 minutes. Strong signals were observed from the scalp muscles and tissues outside the brain, but signal strength from the brain itself was minimal. This was presumably due to the metabolism of [1-13C] glucose in the brain. Little difference was recognized between [1-13C] glucose images of the heads of rats with and without anesthesia. Chemical shift imaging of carbon-13 could be useful methods for the in vivo study of physiochemical structures and metabolic pathways of living organs.


Correlates of battering during pregnancy.

Battering during pregnancy affects the health of both pregnant women and their unborn children. The purpose of this retrospective study of 488 primarily Medicaid-eligible postpartum women was to identify the constellation of factors associated with violence. The prevalence of battering during pregnancy was 7%, similar to that found in other studies. Significant correlates of battering included anxiety, depression, housing problems, inadequate prenatal care, and drug and alcohol use. Woman battering by a partner during pregnancy was associated with a greater severity of this constellation of patterns than those experiencing abuse before pregnancy only, or those experiencing physical attack by someone other than their partner. These factors are important to recognize in nursing assessment of pregnant women.


Psychometric examination of instruments using aggregated data.

The techniques used to examine the psychometric properties of instruments that measure concepts where individual responses are aggregated to form an index describing a group level phenomenon are reviewed. This examination includes assessing the content validity of items to determine how well they measure group level concepts as well as analyzing reliability and validity at the aggregated rather than individual level. Additional techniques to test for within and between group variability are presented. The latter approaches are useful in determining the consistency and adequacy of individual responses at the group level.


Alterations of the circadian melatonin rhythm by the electromagnetic spectrum: a study in environmental toxicology.

The nightly production and secretion of melatonin by the pineal gland, an endocrine organ near the anatomical center of the brain, provides important time-of-day and time-of-year information to the remainder of the body. In mammals, the circadian rhythm of melatonin (low levels during the day and high levels at night) is synchronized by the prevailing light:dark environment with the retinas of the eyes doing the photoreception required for the induction of this rhythm. The advent of artificial light sources has allowed animals or humans to be exposed to light at unusual times, i.e., during the night. Light falling on the retinas at night leads to a rapid depression in the production and secretion of melatonin by the pineal gland. The magnitude of the drop in circulating melatonin due to light exposure at night is related to the brightness (intensity) as well as the wavelength (color) of light to which humans are exposed. The lowered melatonin values following unusual light exposure at night provide erroneous information to a number of organs that respond to the melatonin message since the signal implies it is day when, in fact, it is still night. Besides visible light, certain ultraviolet wavelengths as well as extremely low frequency electric and magnetic fields may also disturb the melatonin rhythm. These nonvisible wavelengths may influence the circadian melatonin rhythm by mechanisms similar to those by which light causes disturbances of melatonin production and release.


Hepatotoxicity and carcinogenicity in female Sprague-Dawley rats treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD): a pathology working group reevaluation.

Risk assessment for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been based in part on the incidences of liver neoplasms in female Sprague-Dawley (SD) rats reported in a 2-year study conducted by Dow Chemical Corporation and published in 1978. In the years subsequent to the Dow report, the criteria for the diagnosis of proliferative hepatocellular lesions in the rat have been refined based upon ongoing study of these lesions. Because of this, PATHCO, Inc., was requested to conduct an independent review of the liver slides from the Dow TCDD study in order to assess how the current terminology might impact on interpretation of proliferative liver lesions in rats compared to the terminology used in the past. In March 1990, a pathology working group (PWG) was convened to review proliferative lesions in the livers of the female rats. The results of the PWG's evaluation of the microslides indicated a trend in tumor incidence similar to that published in 1978 but with a lower incidence of tumors in the middle and high dose females. Based on the morphologic findings, including the fact that the tumors were predominantly benign and usually associated with lesions of hepatic toxicity, the PWG considered this study to demonstrate a weak oncogenic effect of TCDD in the livers of female SD rats. As a result of its review, the PWG noted that in order to establish a relationship between the toxic hepatitis and the hepatocellular neoplasms, an independent review and grading of the toxic lesions in all female rats would be required.(ABSTRACT TRUNCATED AT 250 WORDS)


A review and biological risk assessment of sodium saccharin.

Dietary sodium saccharin is associated with bladder tumors when fed at high levels to the male rat. Under these conditions urinary pH, sodium concentration, and volume are elevated and proliferative changes are present in the urothelium. Extensive epidemiological studies have shown that saccharin does not increase the risk of bladder cancer in humans and laboratory investigations have shown that sodium saccharin is not mutagenic and does not bind to DNA. Recent research indicates that the urothelium in male rats is damaged under conditions of high urinary pH and sodium levels by a mechanism that involves alpha 2u-globulin and possibly silicate crystalluria. These studies and their implications for human health risk are reviewed.


Cancer risk--does anyone really care?

Congress has enacted numerous laws in an attempt to protect people from carcinogens. But neither regulators nor oncologists can hope to accomplish this protection via studies in epidemiology. Nor can they hope to accomplish this using unverified models in carcinogenesis bioassays. The only viable hope is to test and utilize models of carcinogenicity that will tell us what we really need to know; i.e., does this substance pose a reasonable risk of carcinogenesis in man? And if so, what is a quantitative estimate of that risk? There is a substantial number of known human carcinogens. Yet, the most elaborate cancer-testing facility in the world continues to operate without the benefit of validating its results using positive controls (known human carcinogens). Without such controls to gauge the potency of the response in the test animal, Congress can pass 10,000 more laws and still the public will remain unprotected.


Alternative acute inhalation toxicity testing by determination of the concentration-time-mortality relationship: experimental comparison with standard LC50 testing.

A new design for acute inhalation toxicity testing was evaluated and compared with results obtained according to OECD guideline 403. The new design consists of a range-finding test, which is compatible with a conventional limit test, and can be followed by determination of a concentration-time-mortality relationship, enabling calculation of LC50 (50% mortality exposure concentration) values. By exposing pairs of rats for different periods of time to about four different test concentrations in a nose-only exposure unit, LT50 (50% mortality exposure time) values were obtained for five pairs of animals per concentration. The mortality data of the approximate 20 time-concentration combinations were used to calculate the probit relationship. Estimated mortality responses from these probit relations were compared with mortality figures obtained by exposing groups of five male rats and five female rats whole-body according to conventional toxicity testing. In general, there was good correspondence between the estimated and the observed mortality response. In our hands, the determination of the concentration-time-mortality relationship takes about the same number of animals (40-50) as the conventional LC50 procedure according to the OECD guideline 403. However, the new method has several additional advantages such as: (A) LC50 values are obtained over a 10-fold range in time, with the potential of decreasing the number of animals used when regulations require acute toxicity data for different periods of exposure. (B) The obtained relationship contains considerably more valuable information for risk assessment than the LC50 value.(ABSTRACT TRUNCATED AT 250 WORDS)


Scientific and practical considerations for the development of occupational exposure limits (OELs) for chemical substances.

Occupational exposure limits (OELs) serve occupational health professionals as benchmarks for a healthy work environment. OELs are generally developed by manufacturers for substances which are not subject to governmental regulation or which have not been evaluated by consensus organizations such as the American Conference of Governmental Industrial Hygienists. This review is intended to serve as a practical guide to the standard-setting process. The discussion encompasses the evaluation of data, the different methods used for calculating limits, and the application of these limits to the workplace. The need for additional research to enhance the reliability of current methods is also discussed.


[The normal topographic and CT-tomographic anatomy of the ostiomeatal complex].

Recent advances in the pathophysiology of the nasal cavity and paranasal sinuses and the development of endoscopic equipment and techniques have led to a new "functional" surgical management of chronic or recurrent sinusal conditions. The ostiomeatal complex is a narrow and intricate passage way providing aeration and mucus clearance from anterior ethmoid sinus, maxillary sinus and frontal sinus. CT, allowing the detailed demonstration of normal and abnormal patterns of the ostiomeatal complex, permits accurate preoperative planning, which has reduced the number of surgical complications. Ostiomeatal complex anatomy and the corresponding CT features are analyzed, as seen in 85 patients with or without rhinosinusal inflammatory lesions. The CT technique with coronal and axial scans and electronic parasagittal reconstructions, is also reported. Finally, the images obtained on different CT planes are compared, as proposed by other authors.


[Interventional radiology in the treatment of the complications from interventions on the lower urinary excretory tract].

Ureteral diversions may be complicated by strictures, hydronephrosis, pyelonephritis, lithiasis, fistulas, etc. In the last 10 years, 103 patients with 133 urological postoperative complications underwent percutaneous treatment. Most of the patients had been treated by percutaneous antegrade drainage; afterwards, stricture dilatation, ureteral stenting and stone extraction were performed. In one case a Strecker metallic stent was employed. We have successfully treated 101 of 133 complications (75.9%), with only 27 failures (20.3%). Five cases (3.8%) of lithiasis did not require percutaneous treatment. The good results obtained, the absence of major complications, the low cost and the little discomfort for the patients confirm the leading role of percutaneous treatment in complicated ureteral diversions.


[A comparison between quantitative computed tomography and dual-energy densitometry in the study of patients at risk for postmenopausal osteoporosis].

A comparison was made of the densitometric values of the lumbar vertebrae obtained using quantitative Computed Tomography, and those measured with dual energy X-ray absorptiometry. A selected group of patients at increased risk of developing postmenopausal osteoporosis was chosen: women who had undergone bilateral oophorectomy in child-bearing years. The densitometric data recorded revealed a considerable decrease in bone mass, in particular in the cancellous portion of the vertebrae (a 17% change in the quantitative Computed Tomography value and a 13% decrease in that of dual energy X-ray absorptiometry a one year after oophorectomy). Although quantitative Computed Tomography and dual energy X-ray absorptiometry demonstrated a similar trend in bone mass reduction, given the marked and unexplained variability of both absolute values and percent variations, it was impossible to establish a clinically useful mathematical correlation between the two sets of data. Quantitative Computed Tomography is the densitometric procedure of choice to study metabolic bone disorders that involve mainly tha cancellous portion, such as postmenopausal osteoporosis. Nevertheless, given its accuracy, short execution time, lower radiation dose required, as well as good sensitivity in the measurement of bone mass variations, it would seem that dual energy X-ray absorptiometry could also find a place in clinical studies on postmenopausal osteoporosis.


[The results of definitive transcutaneous radiotherapy in the treatment of oropharyngeal neoplasms].

From January 1976 to December 1986, 199 patients with oropharyngeal cancer were submitted to definitive radiotherapy. Survival and local control were analyzed and related to different parameters--i.e, T and N categories, histopathologic grading, tumor location, patients age, and radiation dose. Fifty-six per cent of patients (111/199) died from neoplastic disease within 5 years. Local progression, recurrence or metastases were observed in 149 cases (75%). Ninety-three per cent of first failures (138/149) were related to residual disease or to locoregional relapse while distant metastases occurred in 14 patients only. The majority of locoregional failures (94%) appeared within 2 years, with a mean disease-free interval of 8 months. Tumor recurrence in the primary location was observed to be the first cause of failure in 78% of relapsed patients; moreover, it was the sole cause of failure in half of the unfavorable events. On the contrary, nodal relapse appeared in 38% of treatment failures and in 12% only it was the sole cause of failure. Overall and disease-free survival were observed to depend mainly on T and N categories, while histopathologic grading was seen to affect only early response rate. No significant differences were observed depending on tumor site and patients age. Local control rates depended on total radiation dose, but the difference between low dose (NSD less than 1700) and high dose (NSD greater than 1700) was significant only for T1 and T2 patients.


[Radiotherapy in the treatment of Merkel cell tumors].

Merkel cell carcinomas are very rare (80 cases up to 1986) and very malignant; they have been known for 20 years only as "trabecular carcinomas". They do not rise from neural crests, and therefore are not apudomas, but from a staminal cell of the skin with neuroendocrine evolution. Merkel cell carcinomas must be distinguished from undifferentiated carcinomas of the skin, lymphomas, and oat cell carcinomas. Eight patients (46 to 86 years old) are presented, 4 males and 4 females, with 1 gluteal (the younger female patient), 3 head and 4 limb localizations of Merkel cell carcinoma. Radiotherapy was carried out after surgery in 7 patients and after biopsy in 1; local recurrences were already present in 3 cases, and lymph node metastases in 5; tumor doses were 36-65 Gy, administered with different techniques, i.e. roentgen therapy, telecobalt therapy, 192Ir curietherapy. Chemotherapy was used in 2 metastatic patients only. Four patients are alive and free of disease and 4 are dead; 3 of the living patients have been followed 3-26 months. The high risk of radiation damage (1 necrosis, 2 giant edemas, 1 severe fibrosis) recommends that large fields and high single and/or total radiation doses be avoided. In conclusion, surgery is diagnostic but not curative on account of the high risk of recurrence; radiotherapy is important because Merkel cell carcinomas are very radiosensitive. Due to easy lymphatic spread of this type of cancer, radiotherapy must include the regional lymph nodes (dose: 40-50 Gy). The role of chemotherapy is still to be assessed but many antiblastic drugs are effective.


[Ambulatory monitoring of left ventricular function with a radionuclide detector system].

The recent development of new radionuclide detectors allows noninvasive outpatient monitoring of left ventricular function. This study was aimed at describing a new radionuclide technique useful to monitor cardiac function and at evaluating its potential clinical applications. We studied 14 normal subjects, 30 patients with coronary artery disease and 25 patients with dilated cardiomyopathy. Left ventricular function was continuously monitored in control conditions at rest, during daily physical activity of different intensity (walking on a level surface and climbing stairs), and during bicycle exercise. Left ventricular ejection fraction (EF) variability during recording in control conditions at rest was 0.2 +/- 1.8%. A significant relationship between outpatient EF at rest and conventional equilibrium radionuclide angiography was observed (r = 0.97, n = 69, p less than 0.001). In normal subjects both daily physical activity and exercise stress test induced an increase in heart rate and EF. In patients with coronary artery disease and in patients with dilated cardiomyopathy a heterogeneous EF response was observed during physical activity and exercise stress test. Our results demonstrate that this technique can be used for the ambulatory monitoring of left ventricular function in both normal subjects and patients with different types of cardiomyopathies.


[Magnetic resonance in the diagnosis and follow-up of soft-tissue sarcomas].

The authors analyze the advantages of MR imaging in the detection, staging and follow-up of malignant soft-tissue sarcomas. The role of MR imaging is retrospectively evaluated in 34 patients (16 men and 18 women) ranging in age from 3 to 82 years (mean: 38); 19 of them had a primary neoplasm, while the extant 15 patients were examined after surgery, and residual or recurrent tumors were present. Ten examinations were performed on an 0.5 T imager (CGR Magniscan 5000), and 27 were obtained with a 1.5 T system (Magnetom 42 SP Siemens). In all cases T1 and T2 sequences were acquired; in 3 patients T1-weighted sequences were performed after Gd-DTPA administration. In the 19 patients with primary tumors pathologic specimens were obtained. The value of MR imaging in the evaluation and characterization of soft-tissue sarcomas and its capabilities in detecting neurovascular encasement and bone involvement are discussed. Post-Gd-DTPA scans may help in the differentiation of necrotic areas from active tumors. MR diagnostic criteria of malignancy, including tissue heterogeneity and irregular margins, were not fulfilled in 3 of the studied cases.


[Microcalcifications in the diagnosis and follow-up after the primary chemotherapy of breast neoplasms].

Since 1998, at the National Cancer Institute (Milan, Italy), a study has been carried on relative to primary chemotherapy for locally advanced breast cancers (greater than 3 cm diameter). Aim of the study is to obtain tumor reduction and thus allow a conservative treatment to be performed. The measures of the two greatest diameters of the tumor by means of mammography, at diagnosis and after chemotherapy, are important parameters for treatment planning. Among the 213 patients who completed the whole diagnostic-therapeutic procedures by December 1990, the authors chose 94 cases (44%) presenting breast cancers with microcalcifications and reviewed the relative mammograms. The review was aimed at analyzing morphology, number and extent of the microcalcifications and at assessing their value as reliable parameters of cancer response to primary chemotherapy. In their experience, the authors found that increased visibility of the microcalcifications after chemotherapy is often due to a reduction in both edema and lesion opacity. On the contrary, fewer microcalcifications may be correlated with incisional diagnostic biopsies. In conclusion, if microcalcifications are a useful parameter for diagnosis, they alone are less important when evaluating response to primary chemotherapy, since they probably represent a permanent sign of the extent of the primary lesion. All follow-up mammograms of the patients who underwent conservative surgery were also reviewed: no residual microcalcifications or other suspicious abnormalities were observed.


[Magnetic resonance in the diagnosis of thyroid diseases].

Previous clinical experience in the study of the soft tissues of the neck region has pointed out the accuracy of MRI in terms of high definition and contrast resolution. Seventy-seven patients with thyroid diseases were examined to define the possible role of MRI in the diagnosis of these conditions. In the patients affected with thyroiditis, MR findings were not specific, showing increased glandular volume and signal inhomogeneity. MR examinations of struma allowed an accurate evaluation of glandular size; furthermore, more information was obtained than with other imaging modalities in the cases with mediastinal involvement. On T2-weighted images, adenomas were always hyperintense, whereas variable signal intensity was seen on T1-weighted scans, with the exception of Hürthle cell adenomas, which were hyperintense on both T1- and T2-weighted sequences. MRI proved to be reliable in the depiction of tumor spread at both glandular and extraglandular levels. The distinction between scar fibrosis and relapse was also possible, in the cases undergoing postoperative follow-up. In conclusion, MRI emerges as a diagnostic tool complementary to other imaging techniques. However, in selected conditions--e.g., mediastinal struma and tumors--and in the postoperative follow-up, MRI can be considered the method of choice.


[An accessory musculus soleus (symptomatic and asymptomatic). The CT findings].

The authors have reviewed 90 CT exams of the foot to identify the presence of the accessory soleus muscle, an anatomic variant corresponding to the finding of a medial backtibial tumefaction, often aching, especially of the Achilles-calcaneal-plantar system. In these cases, US is generally required to demonstrate the alteration, which was an occasional finding in the past, and to exclude the presence of inflammatory or expansile processes of the soft tissues. The accessory soleus is characterized by the presence of accessory muscle fibers, which, in variable number, caudally make for the medial aspect of the calcaneus from the antinode of the soleus muscle. The anatomic variant is much better evidenced by CT, more frequently employed than MR imaging, thanks to its easier approach. As a matter of fact, both methods are capable of defining the relationships with the adjacent tendinous-vascular-nervous structures, involved by mechanical friction in the event of muscle hypertrophy due to overload. Indeed, the review of CT examinations has pointed out a relative relationship between volumetric changes in the soleus and nonphysiological functional demands, giving further evidence of its specific role in the efficiency of the Achilles-calcaneal-plantar system. Therefore, the report in asymptomatic cases is an important prognostic factor which allows the correct clinical picture of subsequent painful symptoms.


[Incompetence of the m. gemellus veins in varicose veins: its incidence and phlebographic study].

The authors report on 466 venographies of the lower limbs performed over the past 2 years on 412 patients affected with varicose veins. Pathologic reflux of the gastrocnemius veins was observed in 15.7% of cases: 9.7% in the group of non-operated patients and 25.3% in the group with recurrent varicose disease. Ascending venography (and eventual popliteal venography) is the ideal diagnostic approach to show gastrocnemius veins incompetence, eventual anatomic variations, and isolated/associated incompetence of the short and/or long saphenous vein territory. Moreover, venography allows the hemodynamic evaluation, and shows reversed flow in the gastrocnemius veins in case of incompetence.


[The hemodynamic significance of the angiographic changes after portasystemic shunting interventions for portal hypertension].

Seventy-two patients (52 males and 20 females, mean age: 50.6 years) were studied. They had undergone distal splenorenal shunts according to Warren and its modifications for portal hypertension. All patients were examined with digital and/or conventional angiography preoperatively and 15 days postoperatively. Preoperative and postoperative angiography was employed to evaluate the changes in vessel diameters including the hepatic, splenic and superior mesenteric arteries, the splenic, superior mesenteric and portal veins; the length of the main axis of the spleen was also measured. Furthermore, the degree of hepatic portal venous perfusion was evaluated according to the degree of portomesenteric-gastrosplenic disconnection. After surgery, the length of the main axis of the spleen is reduced and the hepatic artery diameter is increased, which are both signs of preserved hepatic flow and of reduced hypertension in the splanchnic venous system. The postoperative degrees of portal perfusion were correlated with the degrees of disconnection. In conclusion, the role is emphasized of early angiographic examinations after distal portosystemic shunts according to Warren to evaluate postoperative hemodynamic changes.


[Mammography and echography in male breast pathology].

From January 1988 through December 1991, 81 men were examined for breast enlargement or mass in our Institute, by means of clinical examination, mammography, and US. The patients' age ranged 15-71 years (mean: 52 years). Of 81 studied patients, 71 had gynecomastia, 8 had adipomastia, 1 had an infiltrating ductal carcinoma, 1 an angiofibrolipoma and 1 a simple cyst. Both the carcinoma and the cyst were associated with gynecomastia. Three mammographic patterns of gynecomastia were observed: a glandular pattern in 42 cases (32 bilateral and 10 monolateral), a dendritic pattern in 12 (8 bilateral and 4 monolateral), and a nodular pattern in 15 (9 bilateral and 6 monolateral). On US, gynecomastia appeared diffuse in 54 patients and focal in 15. The infiltrating ductal carcinoma was clinically evident; no asymptomatic cancers were detected. Surgical biopsy was performed in 40 cases. A good correlation was observed between mammographic and US signs. The combined use of the two modalities can improve diagnostic accuracy. Biopsy must be performed in all questionable cases.


[Intestinal tuberculosis. The radiologic aspects of a disease not to be overlooked].

Intestinal tuberculosis still exists in the Western world, where it is usually underestimated and often mistaken for Crohn's ileo-colitis or cancer. The authors report the results of 4 cases of intestinal tuberculosis observed between 1983 and 1988. The cases are discussed in the light of the epidemiological data emerging from a review of recent medical literature. The danger is that the disease, which is endemic in Asian and African regions, may spread again in the Western world fostered by intensifying migrations of people and by the spreading of AIDS. According to recent experience, a negative chest film and Mantoux skin-test no longer have a negative predictive value for intestinal tuberculosis. In the radiological differentiation from Crohn's disease it is useful to keep in mind some topographic features of TBC: the systemic non-discontinuous involvement of both sides of ileocecal junctions; the unusual presence of ileal lesions, with no cecal lesions, and localizations below the transverse colon. Useful differential morphological criteria can be: star-like or transverse ring-shaped profile of isolated ulcerations, tubular ileocolic junction with retracted cecum and open valve, and uniformity of lesion in the comprehensive picture of the clinical case.


[The computed tomographic diagnosis of malignant pleural mesothelioma. A multicenter study].

CT features are described and accuracy of the method is discussed in the diagnosis of malignant pleural mesothelioma. Ninety-eight patients suffering from pleural disease mimicking mesothelioma were examined by means of III-generation CT scanners; according to the final diagnosis, 37 patients suffered from malignant pleural mesothelioma, 27 from other malignant pleural diseases and 34 from various benign diseases. In all patients a series of CT signs was evaluated: pleural thickening patterns, lesion spread and possible associated characters. In the diagnosis of mesothelioma CT showed 72.5% sensitivity, 63.8% specificity, 68.3% diagnostic accuracy, 68.5% positive predictive value and 68.2% negative predictive value. Some significant CT patterns in distinguishing malignant from benign pleural disease were identified, while the characterization of malignant disease (mesothelioma versus other neoplastic conditions) proved to be unreliable.


Acute renal failure during the Korean War.

Oliguric ARF occurred in 0.5% of battle casualties who reached the field medical care system and raised their mortality expectancy from less than 5% to nearly 90%, due primarily to fluid volume overload and/or myocardial potassium intoxication. For their effective treatment the Renal Insufficiency Center with laboratory and a Brigham-Kolff rotating drum dialyzer began operations in 1952, as depicted in a videotape prepared for this presentation from motion picture footage filmed in early 1953. Our Surgical Research Team's major findings relevant to ARF were: (1) Renal function was depressed in most battle casualties in proportion to the severity of their wounds and blood loss. (2) Among the more severely wounded some developed nonoliguric; others, oliguric ARF. (3) Oliguria lasted from 3 days to 3 weeks without a discernible peak frequency of beginning diuresis at 10 days. (4) During oliguria, posttraumatic catabolism greatly accelerated extracellular accumulations of nitrogen, potassium, phosphate, and hydrogen ion with rapid, concurrent clinical deterioration. (5) Dialysis "on indication" produced an oscillating clinical and chemical course. (6) ARF was then revealed as a wasting disease complicated by infections, poor wound healing until diuresis occurred, anemia and bleeding, and hypertension during dialyses and in early diuresis. (7) The overall mortality rate was reduced.


[The preoperative staging of rectal cancer with endorectal echography].

The authors stress the value of the routine use of endorectal US for the preoperative staging of rectal cancer. This method accurately demonstrates the exact level of the lesion, the degree of circumferential invasion, the depth of local involvement and the extent of eventual spread beyond the rectal wall, the invasion of the surrounding structures and the presence of enlarged perirectal lymph nodes. A hundred and forty-one patients with rectal carcinoma located 3-16 cm from the ano-cutaneous line were examined with endorectal US preoperatively; a comparison was made between US findings and pathological data, so that a correlation could be made between US (uT) and histologic (pT) findings. A radial probe and a 7-MHz transducer were employed. Our results show US accuracy to be 93.6% with only 4 cases of understaging and 5 of overstaging. A hundred and twenty-nine patients who had undergone major surgery were also studied to evaluate US accuracy in lymph node detection: in 110 cases the actual lymph node status was correctly demonstrated; US diagnostic accuracy was 85.3% with 16 false positives and 3 false negatives. The correct evaluation of the actual local tumor spread, as demonstrated by endoluminal US, allows the choice of the correct treatment, together with a personalized therapeutic schedule, to reduce the incidence of local recurrences and to save, whenever possible, sphincter functionality.


Acute renal failure in the Armenian earthquake.

A destructive earthquake devastated northwestern Armenia on December 7, 1988. The size of the affected area (radius of 50 miles), the time of the day when it occurred (11:41 a.m.), deficiencies in the design and construction of buildings, and inadequate initial rescue and relief capabilities resulted in one of the most lethal and traumatic natural disasters of the century. A large but unknown number (estimated at 225 to 385) of the extricated victims who had sustained crush injury developed myoglobinuric acute renal failure requiring dialytic support. The limited number (8-10 dialysis machines) of antiquated dialysis facilities available locally were overwhelmed. International dialysis relief efforts resulted in meeting the immediate acute needs and provided the motivation and elements of the more efficient system for the future delivery of maintenance dialysis.


[New imaging with computed tomography in dental implantology].

The authors report on a new image processing technique, for the imaging of both mandible and maxilla, which is very useful for oral specialists, especially in pre- and postoperative protocols for dental implants. After performing very thin axial scans (1-2 mm) with overlapping and without gantry tilt, of the mandible and/or maxilla, the data are reconstructed with a Elscint DentaCT software. With this program, multiple panoramic alveolar views can be obtained in a very short time (about 5 minutes), with a focal plane which can be easily modified by the operator; these planes are parallel to the curved axis of maxilla or mandible. Furthermore, the operator can get multiple images absolutely cross-sectional to the curved axis of alveolar regions (radial sections) and can image the number of cross-sectional planes and the distance between them. In all studied patients (41 over the last 6 months, 66 images overall), DentaCT yielded an excellent representation not only of all anatomical structures but also of every single implant; this allowed a complete preoperative planning based on morphovolumetric, densitometric and spatial data, together with the correct evaluation of implant positioning and of osteointegration success.


[Double-contrast esophagography in the diagnosis of esophagitis due to Candida. A study on HIV-seropositive patients].

This study was aimed at assessing the sensitivity of double-contrast esophagography in diagnosing Candida esophagitis. This condition accounts for 85% of all esophageal infections in the subjects suffering from AIDS. Thirty-nine HIV+ patients were evaluated: 19 of them had endoscopic diagnosis of Candida esophagitis. Our study confirmed the high sensitivity of esophagography (90%), as reported in the literature. Radiographic findings were edematous esophageal folds in the early stage and, subsequently, plaques and diffuse ulcerations. These patterns are suggestive of anatomical lesions: in the early stage, mucosal edema and erythema are observed, and later on pseudomembranes and ulcerations. None of our patients exhibited stenosis. All the subjects with Candida esophagitis had less than 250/mm3 of CD4 lymphocytes. In conclusion, double-contrast esophagography must be included in the periodic examinations performed on patients with AIDS, so as to allow an early diagnosis.


Acute renal failure in natural disasters.

Sudden-impact natural disasters such as earthquakes present a serious challenge to medical personnel in both developed and less developed countries. Crush syndrome with acute renal failure has been identified as a major medical complication that occurs among people whose limbs are trapped by heavy objects during natural disasters such as earthquakes or volcanic eruptions. Rescue and field medical teams should be trained to recognize and promptly treat the problems associated with prolonged limb compression and should carry the appropriate fluids and medications to treat the complications of traumatic rhabdomyolysis. Early, aggressive volume replacement followed by forced solute-alkaline diuresis therapy may protect the kidney against acute renal failure. Better epidemiologic knowledge of the specific disaster conditions that predispose traumatic rhabdomyolysis to develop is clearly essential for those who must determine when emergency dialysis services are required in response to injuries sustained during natural disasters. Disaster health care personnel involved with providing emergency acute renal care should have a basic familiarity with disaster epidemiology in order to determine whether a given event requires their intervention. This paper includes recommendations for improving medical planning, preparedness, and response to natural disasters that cause acute renal failure.


[Renal echography in diabetes mellitus].

The US findings in the kidneys of diabetic patients were studied. Diabetic subjects without clinical or laboratory signs of nephropathy were investigated by means of US in order to detect early anatomical lesions predictive of renal injury. The kidneys of cadaver diabetics were also studied to correlate US and histologic patterns. US alterations were observed in half of the cases: they were diffuse in 9% of cases and focal in 39%--hyperechoic spots and hyperechoic juxta-medulla. Focal spots are more common in juvenile-onset diabetics and they are correlated with the age of diabetes. At histology the above US patterns were correlated with the vascular wall alterations typical of diabetic nephropathy. Diffuse alterations are not specific. The authors conclude by suggesting US as a prognostic test for diabetic nephropathy.


[Small nodules of adenomatous hyperplasia in the cirrhotic liver. Treatment with percutaneous alcoholization].

Small adenomatous hyperplastic nodules (AHNs) are now detected with increasing frequency in cirrhotic livers thanks to the widespread use of ultrasonography (US) in patients with chronic liver disease. The management of these lesions, which are commonly considered as likely to evolve into hepatocellular carcinomas (HCCs), is difficult: indeed, the surgical resection of a questionable neoplastic lesion does not seem advantageous, if surgical hazards are considered; on the contrary, the simple US/bioptic follow-up may be untimely in the detection of the malignant transformation. Percutaneous ethanol injection (PEI) under US guidance, already employed in the treatment of small HCCs, was recently proposed as a viable therapeutic alternative for AHNs. Our experience includes 16 AHNs submitted to PEI over a 2-year period. The size of the lesions ranged between 0.7 and 2.3 cm. Each nodule was treated on an outpatient basis with 6 weekly ethanol injections; the total amount of alcohol delivered to each lesion was 8-17 ml. No complications occurred. PEI induced volumetric reduction and/or structural modifications of the lesions; 10 of them were hardly differentiable from the surrounding parenchyma at the end of treatment. One month after PEI, CT allowed the detection of 13/16 AHNs; all of them resulted hypodense and showed no contrast enhancement. Repeated biopsies produced necrotic material in all cases. During the follow-up (10-33 months, mean 18.3) no recurrences were observed. At the moment, PEI seems to be the most appropriate therapeutic approach for small AHNs.


Energy metabolism and renal ischemia.

In renal preservation, the longer the organ is cold stored the greater the damage to the organ. The mechanism of hypothermic-induced kidney injury is not known. In this study the effects of long-term preservation (up to 120 h) of the dog kidney on mitochondrial functions in an homogenate of kidney cortex tissue was investigated. Kidneys were exposed to either warm ischemia (0 to 90 min) cold ischemia (0, 72, 96, and 120 h). The mitochondrial oxygen uptake was measured in an homogenate. In both warm and cold ischemia there were changes in the mitochondrial utilization of oxygen. The changes were characterized as a decrease in uncoupler stimulated oxygen uptake by up to 40%, an increase in oligomycin-sensitive respiration by up to about 150%, and a decrease in the respiratory control ratio (uncoupler control ratio) from about 3 to 1. These changes in mitochondrial utilization of oxygen were partially reversed by including albumin in the respiration medium. Albumin binds free fatty acids and these may originate, during ischemia, from the action of phospholipases during ischemia. The changes in mitochondrial oxygen uptake may result from both the loss of membrane-bound phospholipids and the accumulation of free fatty acids. The changes in mitochondrial activity between 72 h (viable kidneys on transplantation) and 96 to 120 h preservation (nonviable kidneys) were not significant. Furthermore, reperfusion of kidneys preserved for 72 to 120 h resulted in a restoration of mitochondrial oxygen uptake to near normal (control) values. Thus, it does not appear that the limitation of successful long-term renal preservation is due to mitochondrial injury caused by cold ischemia.


[Magnetic resonance in the staging of renal carcinoma. The results compared with computed tomography in 42 cases].

In order to investigate the value of MRI in the staging of renal cell carcinoma and to compare the results of MRI and CT, the authors evaluated by means of MRI and CT 42 patients affected with renal cell carcinoma. All patients underwent surgery, and pathology of the surgical specimens was performed. A comparison was made between the surgical and pathologic data and MRI and CT results. Moreover, a comparative evaluation of MRI and CT findings was also made. From the comparison between pathologic data and CT and MRI results MRI was seen to have correctly staged 36 of 42 cases (85%), versus CT 33 of 42 cases (78%). Moreover, MRI proved to be superior to CT in evaluating venous involvement (stages III A and III C) and extra-fascial tumor spread (stage IVA). On the contrary, no significant differences were found between MRI and CT in the evaluation of perirenal involvement (stages I-II) and lymph node metastases (stage III B). MRI misdiagnosed 6 of 42 cases: 2 false negatives in evaluating extracapsular tumor spread, 1 false positive of mesenteric infiltration, 1 false positive of renal vein thrombosis, 1 false positive and 1 false negative in evaluating lymph node metastases. CT misdiagnoses (9 of 42 cases) were the same as those of MRI in 5 cases, while in the MRI false positive of renal vein thrombosis CT was correct. The extant 4 incorrect CT findings were: 2 false positive of renal vein thrombosis, 1 false negative of infiltration of diaphragm and psoas muscle, 1 false positive infiltration of the right liver lobe. As yet, therefore, MRI cannot be routinely employed to stage all renal cancer patients. On the contrary, MRI should be considered as a second-choice diagnostic tool to employ in selected cases when CT alone cannot solve all the problems relative to staging.


Free radical-mediated postischemic injury in renal transplantation.

Oxygen free radicals are generated during reperfusion of ischemic organs. Studies employing several species of laboratory animal (rat, dog, pig, rabbit, mouse) have documented protective effects of a variety of free-radical scavengers and antioxidants when administered before or immediately preceding reperfusion of ischemic kidneys. These protective agents include superoxide dismutase, dimethylthiorea, dimethyl sulfoxide, alpha-tocopherol, glutathione, the iron chelator deferoxamine, probucol, allopurinol and oxypurinol, and the spin-trapping agent PBN. Furthermore, deficiency of antioxidants (selenium, alpha-tocopherol, or catalase) exacerbates postischemic renal injury. These findings have been applied to renal transplantation in an attempt to decrease the incidence of posttransplantation acute renal failure. This is important because acute renal failure results in morbidity, increases hospital stay and the cost of transplantation, and complicates the use of cyclosporine. In porcine and in canine kidney transplantation, superoxide dismutase and allopurinol have provided renal protection. Transplantation is complicated because there may be prolonged hypoperfusion before harvesting plus a brief period of total ischemia during harvesting, followed by a prolonged period of cold ischemia and/or reperfusion, then followed by another brief period of ischemia and reperfusion during transplantation. Injury may occur at each of these phases by different mechanisms.


[A protocol for evaluating screen-film systems].

When a competition is made for the supply of sensitive photographic material, each USL is asked, in a time scan of one or more years, to evaluate the characteristics of the screen-film systems proposed by the various companies. In the last years the authors had several opportunities to check different screen-film systems for many Friuli-Venezia Giulia hospitals. For this reason they have set an evaluation form tested after following changes and recently employed in its final version. The check form is reported on in this paper with some personal considerations originated by the authors' experience. The technical parameters which must be evaluated are reported, together with the instrumentation needed to perform the technical examination, the examination modality, and the score-attributing criteria. The evaluation form is very flexible for it allows each Radiology Department to evaluate each parameter in a personal way and to fit it to its own needs.


Therapeutic implications of arachidonic acid metabolism in transplant-associated acute renal failure.

Acute renal failure is common in kidney transplantation due to immunologic, nephrotoxic, and ischemic events. In this paper the subject of posttransplant acute renal failure is reviewed in relation to arachidonic acid metabolism. Although experimental abnormalities noted in ischemia, rejection, and cyclosporin nephrotoxicity are discussed separately, it is obvious that in the clinical situation there is great overlap. The effects of altering the substrate arachidonic acid by feeding of dietary omega-3 fatty acids, both experimentally and clinically, are discussed. Finally, the limited clinical trials of prostaglandin analogues in renal transplant patients show conflicting conclusions as regards beneficial effects on rejection and renal function. Careful clinical studies of compounds with proven efficacy in animals are needed if acute renal failure posttransplant is to be modified or prevented.


Osmotic diuretics and hemodilution in postischemic renal failure.

In the acute phase of ischemic renal failure, the severe depression of the glomerular filtration rate (GFR) is due to obstruction of the tubules by cells and cell debris rejected from the proximal tubules, a blockade which can be prevented at least partly, by treatment with osmotic diuretics. The isosthenuria, the second typical sign in ischemic acute renal failure, probably derives from the medullary ischemia that results from an intracapillary trapping of red cells. This, in turn, is suggested to be caused by oxygen-derived free radicals, which via increasing the capillary macromolecular permeability result in a massive extravasation of plasma and hence in hemoconcentration. As expected from this hypothesis, scavengers may ameliorate both the trapping and the consequent medullary ischemia. Unfortunately, however, a therapy using both osmotic diuretics and scavengers fails to improve the long-term outcome. Hemodilution would seem more promising, since it will both prevent the medullary ischemia seen in the acute phase and substantially improve the long-term outcome. At a hematocrit of 0.30, rat kidneys exposed to 45-min ischemia will show a GFR 1 month after the insult of more than 50% of the normal GFR as against 15% in untreated animals.


Protective effect of dicalciphor during mitochondrial failure.

Mammalian cells differ considerably in the duration of anoxia which they can tolerate despite the fact that dramatic bioenergetic changes occur rapidly. Previous studies indicate that the ability to tolerate anoxia is at least partly due to an endogenous signal transduction system that senses O2 deficiency and signal altered ion transport functions in the mitochondria. The responses included inhibition of ATP synthase, ADP/ATP exchange, inorganic phosphate uptake, mitochondrial swelling, and loss of the mitochondrial proton-motive force. An important distinction between KCN toxicity and anoxia is that KCN does not elicit these protective mechanisms. Thus, the ability of a compound to elicit these mechanisms in KCN-treated cells provides an assay for potential agonists of the endogenous protective mechanisms.


Renal vasculature and ischemic injury.

Functionally similar ischemic acute renal failure (ARF), as estimated by glomerular filtration rates (GFR), was induced by renal artery clamping (RAC) or intrarenal norepinephrine (NE) in rats and renovascular reactivity was examined at 1 week. With RAC-ARF induction there was total renal ischemia followed by abrupt return of renal blood flow (RBF). With NE-ARF induction there was subtotal ischemia (10-15% of basal RBF) with RBF recovery over several hours. Renovascular resistance (RVR) did not change to renal perfusion pressure (RPP) reduction in the autoregulatory range in RAC-ARF but paradoxically increased in NE-ARF. There was an exaggerated response to renal nerve stimulation in NE-ARF but no response in RAC-ARF. There was a vasoconstrictor response to intrarenal norepinephrine in the former but a negligible response in the latter. There was no vasodilation to acetylcholine in either group, but there was a normal response to prostacyclin in NE-ARF. Smooth muscle necrosis was found in 46% of resistance arterial vessels in RAC- but in only 8% of NE-ARF (p less than .001). When mean arterial pressure was reduced to 90 mm Hg for 4 h at 1 week, recurrent azotemia and fresh ischemic injury were noted in NE- but not RAC-ARF. It is concluded that different models of ischemic ARF induction result in different patterns of abnormal postischemic vascular reactivity. Differences in vascular smooth muscle and endothelial injury are due to differences in initial ischemia or rates of postischemic reperfusion.


Glutathione and glycine in acute renal failure.

Glutathione is an important intracellular antioxidant in virtually all tissues, including the kidney. In the kidney, it has a rapid turnover in tubule cells and likely plays a role in any oxidant-related events which contribute to the tubule cell injury which occurs during acute renal failure. It was surprising, therefore, to find that the component amino acid, glycine, rather than glutathione itself, most strongly modulated the sensitivity of tubules cells to a variety of insults in several in vitro systems where these processes can be studied most directly. This paper reviews available evidence concerning the nature of both glutathione and glycine effects, their expression in vivo in in vitro, and their implications for understanding acute renal failure.


Determinants of intrarenal oxygenation: factors in acute renal failure.

Oxygen tension within the renal parenchyma is influenced by two factors: metabolic demand and oxygen supply. There are three regions within the kidney in which there is an anatomical basis for limited oxygen availability. The first is the inner stripe where oxygen diffusion between arterial and venous vasa recta reduces PO2. The other two are the outer stripe and medullary rays which are fed by O2-poor blood from venous vasa recta. The balance between oxygen demand and supply is most critical in the inner stripe where the PO2 is most influenced by transport activity. In contrast, altering transport activities in the outer stripe will not change the prevalence of hypoxic S3 injury but will alter its type (i.e., cell fragmentation related to high GFR and increased workload versus cell edema related to low GFR and minimal workload). The effect of transport activity on medullary ray PO2 has not been well defined. Using sensitive oxygen microelectrodes, cortical PO2 (52 +/- 2 mm Hg) in the rat was found to be higher than medullary PO2 (21 +/- 2 mm Hg, p less than 0.001). How are these observations reflected in current models of acute renal failure? The ischemia-reflow model affects proximal tubules with a predilection for S3 (located within the outer stripe of medulla) after short-term ischemia. With hyperfiltration (induced by glycine or renal hypertrophy) and the pursuant increase in transport related O2 demand, hypoxic mTAL inner stripe injury becomes prominent. Renal parenchymal hypertrophy exaggerates injury in the contrast nephropathy model, in which mTAL inner stripe injury is a predominant feature and medullary PO2 is very low.(ABSTRACT TRUNCATED AT 250 WORDS)


Calcium channel blockers: protective effects in ischemic acute renal failure.

Studies in heart, liver, and kidney have provided evidence that calcium is an important factor in cell injury. Calcium channel blockers are used with increasing frequency in ischemic and toxic renal failure. In this review the available data on the effects of calcium channel blockers in animal models of ischemic renal failure are presented and possible mechanisms of protective actions are discussed.


Drug-phospholipid interactions: role in aminoglycoside nephrotoxicity.

Aminoglycoside antibiotics are known to be transported and accumulated within lysosomes of renal proximal tubular cells and to cause proximal tubular cell injury and necrosis. The pathogenesis of aminoglycoside nephrotoxicity is postulated to be related to the capacity of these organic polycations to interact electrostatically with membrane anionic phospholipids and to disrupt membrane structure and function. Aminoglycoside antibiotics have been shown to bind to anionic phospholipids of model membranes and to alter membrane permeability and promote membrane aggregation. In vivo these drugs induce phospholipiduria and a renal cortical phospholipidosis. The latter reflects the accumulation of phospholipid-containing myeloid bodies within the lysosomal compartment consequent to aminoglycoside-induced inhibition of lysosomal phospholipases. The mechanism of drug-induced inhibition of phospholipases has been shown to be secondary to the binding of these cationic drugs to anionic phospholipids. As the lysosomes became progressively distended with myeloid bodies, they become unstable and eventually rupture, which results in the release of acid hydrolases as well as high concentrations of aminoglycosides into the cytoplasm where they interact with and disrupt the function of other membranes and organelles including mitochondria and microsomes. It is postulated that the redistribution of drug from the lysosomal compartment to organellar membranes is the critical event which triggers the irreversible injury cascade. Polyaspartic acid is a polyanionic peptide which when administered in vitro or in vivo forms electrostatic complexes with aminoglycoside antibiotics and prevents these drugs from interacting with anionic phospholipids, from perturbing phospholipid metabolism and from causing cell injury and necrosis.


Alterations of membrane fluidity by toxic injuries.

Alterations in membrane fluidity affect, via an effect on the ease with which proteins may change conformation, the activity of various enzymes and transport systems. Recent experiments have shown that toxic injury is frequently associated with modifications in physical state and/or lipid composition of plasma membranes. Such modifications are likely to play a role in cell dysfunction, especially in epithelial cells whose optimal function depends on the polarity in membrane fluidity between apical and basolateral domains.


Renal proximal tubule cell cultures for studying drug-induced nephrotoxicity and modulation of phenotype expression by medium components.

The characteristics of two established renal cell lines (LLC-PKI and OK) and of primary cultures of rabbit and human proximal tubule cells are described by summarizing the literature about specific properties retained by these cells in culture. Furthermore, comparative biochemical and functional properties are presented including both specific marker enzymes and transport properties of these cells grown in various media. The impact of culture medium composition on the expressed cellular phenotype is discussed and its consequences on the profile of toxic response due to aminoglycoside antibiotics is analyzed. The in vitro nephrotoxicity of three platinum-containing coordination complexes which exhibited different in vivo nephrotoxic potentials is studied by another technique in a model of rabbit proximal tubule cells in primary cultures in order to correlate results to in vivo data and to define reliable and sensitive parameters for the assessment of platinum-derivative-induced nephrotoxicity. Although animal cell lines have been established in serum-supplemented medium, LLC-PK1 and OK cells as well as primary cultures of proximal tubules are successfully grown in hormonally defined medium, the standardization of which is better controlled for nephrotoxicity studies.


Acute renal failure secondary to leukocyte-mediated acute glomerular injury.

Acute glomerulonephritis can cause acute renal failure. Activated neutrophils and monocytes are major effectors of glomerulonephritic renal failure. Adhesion molecules, granule enzymes, reactive oxygen radicals, lipid metabolites, and cytokines of activated neutrophils and monocytes mediate glomerular capillary constriction, occlusion, and destruction. Injurious products and biologically active mediators released by activated leukocytes have profound functional effects on mesangial cells and endothelial cells, which in turn participate in the disturbance of glomerular function, for example, by altering capillary diameter and surface area. The glomerular inflammatory events result in decreased glomerular capillary ultrafiltration coefficient and glomerular filtration rate, as well as other functional perturbations.


Glomerular coagulation system in renal diseases.

Glomeruli possess a complex hemostasis system with prothrombotic (procoagulant, antifibrinolytic) and antithrombotic (anticoagulant, fibrinolytic) properties that can act locally on platelet adhesion or aggregation, on plasmatic coagulation pathways, and on fibrinolysis. In vitro, inflammatory mediators, such as TNF, favor glomerular thrombogenic properties through enhancement of thromboplastin synthesis and of plasminogen activator inhibitor PAI-1, and through decrease in thrombomodulin activity. In some diseases, intraglomerular fibrin formation appears to be favored by increased glomerular prothrombotic properties, for example: augmented thromboplastin activity in immune glomerulonephritides and in Shwartzman phenomenon, excessive thromboxane A2 synthesis, and decreased fibrinolytic activity in severe renal allograft rejection. In other diseases glomerular hemostasis appears to function homeostatically, for example, in thrombin-induced disseminated intravascular coagulation with enhancement of fibrinolytic activity favoring fibrin dissolution. Novel methods allowing the study of glomerular hemostatic activities in renal biopsy fragments should help to understand the mechanisms of fibrin deposition in human diseases and to treat it on a logical basis.


Bacterial and enzymatic bioassays for toxicity testing in the environment.

Microbioassays using bacteria or enzymes are increasingly applied to measure chemical toxicity in the environment. Attractive features of these assays may include low cost, rapid response to toxicants, high sample throughput, modest laboratory equipment and space requirements, low sample volume, portability, and reproducible responses. Enzymatic tests rely on measurement of either enzyme activity or enzyme biosynthesis. Dehydrogenases are the enzymes most used in toxicity testing. Assay of dehydrogenase activity is conveniently carried out using oxidoreduction dyes such as tetrazolium salts. Other enzyme activity tests utilize ATPases, esterases, phosphatases, urease, luciferase, beta-galactosidase, protease, amylase, or beta-glucosidase. Recently, the inhibition of enzyme (beta-galactosidase, tryptophanase, alpha-glucosidase) biosynthesis has been explored as a basis for toxicity testing. Enzyme biosynthesis was found to be generally more sensitive to organic chemicals than enzyme activity. Bacterial toxicity tests are based on bioluminescence, motility, growth, viability, ATP, oxygen uptake, nitrification, or heat production. An important aspect of bacterial tests is the permeability of cells to environmental toxicants, particularly organic chemicals of hydrophobic nature. Physical, chemical, and genetic alterations of the outer membrane of E. coli have been found to affect test sensitivity to organic toxicants. Several microbioassays are now commercially available. The names of the assays and their basis are: Microtox (bioluminescence), Polytox (respiration), ECHA Biocide Monitor (dehydrogenase activity), Toxi-Chromotest (enzyme biosynthesis), and MetPAD (enzyme activity). An important feature common to these tests is the provision of standardized cultures of bacteria in freeze-dried form. Two of the more recent applications of microbioassays are in sediment toxicity testing and toxicity reduction evaluation. Sediment pore water may be assayed directly or solvents may be used to extract the toxicants. Some of the solvents used for extraction of organic chemicals are themselves toxic to bacteria (e.g., dichloromethane), requiring exchange with a less toxic solvent (e.g., ethanol, methanol, DMSO). A modification of the Microtox test allows direct assay of solid-phase samples such as sediments. The toxicity reduction evaluation (TRE) must be carried out at wastewater treatment plants whose effluents fail toxicity standards. The TREs require numerous and repeated toxicity assays, thus favoring application of microbioassays. Presently, no single microbioassay can detect all categories of environmental toxicants with equal sensitivity. Therefore, a battery of tests approach is recommended. The differential sensitivity of alternative tests may, in fact, be exploited. Further research is needed to construct strains of genetically engineered microorganisms or isolate microorganisms or enzymes that respond to specific classes of toxicants. These can be combined into batteries appropriate for different environments or test objectives.


Environmental cadmium in Europe.

The present article reviews information from the latest 10 years concerning fate and exposure of cadmium in the environment, on ecotoxicological effects, and on critical pathways leading to human and environmental exposure. It emphasizes the situation within the Community of European Countries by referring to limit values used in the EEC and some of its member states for emissions to water, air and soil. Estimates have been made on total emission balances for the Netherlands, Denmark, and for the EEC as a whole. The balances show that 70-90% of all cadmium circulating in the Community is disposed of as waste in solid waste deposits. Production and use patterns are presently changing, as indicated by reduced consumption in recent years of cadmium for plating, stabilizers and pigments in several countries as a result of regulations. However, significant increases in consumption for cadmium-containing batteries have occurred, resulting globally in increasing trends for the total consumption and production. Cadmium in sediments is more mobile than described earlier. Aquatic organisms can be classified in order of decreasing accumulation: algae greater than molluscs greater than crustaceans greater than fish. There is no evidence of biomagnification of cadmium within marine or fresh water food webs. Cadmium may enter into plants via roots or by foliar adsorption following atmospheric deposition. Biomagnification in terrestrial food chains is not observed. The uptake into plants is plant specific. Within plants significant variations are seen with concentrations generally decreasing in the order: roots greater than leaves greater than fruiting parts greater than seeds. A compilation of cadmium in air, in the aquatic environment and in soil is given. A downward trend during the 1970s to mid-1980s seems to be evidenced from various Northern European studies on cadmium air concentrations as well as for deposition rates of cadmium. In rivers, the dissolved cadmium concentrations are generally found to be relatively low (10-500 ng/L). In seawater, cadmium concentrations are found at 0.5-10 ng/L in oceanic or open marine areas, while elevated concentrations are reported in more closed marine areas and especially in coastal zones close to polluted estuaries. In fresh water, lake sediments concentrations 3-30 times higher than the background concentrations are reported in the surface layers of sediments. A significant decrease in such pollution has been observed within the recent 10 years. For marine sediments, enrichment factors of two are found in sediments from open areas and locally even 5-10 times.(ABSTRACT TRUNCATED AT 400 WORDS)


Schedule-induced stereotypy.

The phenomena of the induction and entrainment of adjunctive behaviours was investigated in eight people with severe or profound mental retardation who exhibited stereotypic behaviours. The occurrence of collateral behaviours was investigated under extinction and massed reinforcer baselines and a variety of periodic or intermittent schedules of reinforcement for the performance of a simple experimental task. Seven of the eight subjects demonstrated evidence of schedule-induced stereotypic behaviour in the experimental conditions: five of the eight subjects also showed evidence of the entrainment of these behaviours within the first third of the interreinforcement interval. The results are discussed in relation to the analysis and intervention of problem behaviours in people with severe or profound mental retardation.


A comparative analysis of general case simulation instruction and naturalistic instruction.

Effects of naturalistic instruction and simulation instruction for the acquisition, generalization, and maintenance of housekeeping and janitorial work skills in young adults with moderate and severe mental retardation were assessed. The performance of the four participants (under the two methods of instruction for two job task sequences) was assessed using a multiple probe design across behaviors. Both the naturalistic and simulation instructional methods involved noninstructional probes, instruction sessions, generalization probes, and withdrawal of instruction. Results of noninstructional probes parallel to simulation instruction sessions indicated only a minimal improvement over initial (base-line) noninstructional probes. By contrast, noninstructional probes parallel to naturalistic instruction showed a marked improvement for all four participants with correct responding reaching or exceeding the 90% level. Naturalistic instruction was an effective means of producing skill acquisition, while generalization of the learned skill was marginal.


A case of phenobarbital exacerbation of a preexisting maladaptive behavior partially suppressed by chlorpromazine and misinterpreted as chlorpromazine efficacy.

An adult female with developmental disability was prescribed chlorpromazine for the target behaviors of aggression and self-injurious behavior (SIB), and she was prescribed phenobarbital for seizures. Upon a chlorpromazine minimal effective dose reduction, target behaviors increased and dosage was returned to prior levels with the conclusion that chlorpromazine was controlling the target behaviors. Upon subsequent reduction and discontinuation of phenobarbital, however, chlorpromazine was able to be reduced with no increase in target behaviors. Ten years of behavioral data are presented to support the hypothesis that phenobarbital was exacerbating maladaptive behaviors. Given tardive dyskinesia (TD), clinicians and interdisciplinary teams should remain alert to the following client profile: (1) prescribed phenobarbital (or primidone), (2) prescribed neuroleptics, especially at high dosages, to control maladaptive behaviors, (3) failure of neuroleptic gradual minimal effective dose attempts, and (4) possible presence of behavioral procedures, especially intrusive procedures, to control maladaptive behaviors. This profile should trigger a "red flag" as to the possibility of phenobarbital behavioral side effects or exacerbation of preexisting maladaptive behaviors.


Differential reinforcement as treatment for behavior disorders: procedural and functional variations.

For many years, differential reinforcement has been a prevalent and preferred treatment procedure for the reduction of behavior disorders. This paper reviews the procedural variations of differential reinforcement and discusses their functional properties. It is proposed that such procedures are more likely to be successful if behavioral function is a primary consideration in prescribing treatments; furthermore, limited success noted in previous research may be due to the arbitrary relationship that often exists between reinforcers and target behaviors when behavioral function is unknown. Despite the promise of a function-based approach to differential reinforcement, several current limitations exist in the identification and manipulation of relevant variables. Thus, further research is required to elucidate the relationship between aberrant behaviors and the variables responsible for maintaining them; otherwise, successful treatment cannot be expected. Several areas for future research are discussed conceptually as extensions of current and past experimentation.


[The visco-elastic behavior of the respiratory system during mechanical ventilation. Interpretation with the aid of a model].

The purpose of this review is to present an approach to the visco-elastic properties of the respiratory system in the mechanically ventilated patient through the method of occlusion of the airways at a constant inspiratory flow rate. The ideas of airways resistance, tissue resistance, static and dynamic elastance are defined from the theoretical point of view and also from the point of view of the occlusion method. A large part is given to the bicompartmental model describing the visco-elastic properties of the lung and of the thoracic wall. Recently carried out experimental studies both in healthy man and in disease have given results which seem to confirm the predictions made by this model. According to this system the lungs may be represented as a homogenous whole surrounded by visco-elastic components.


[Physiopathological bases for retraining programs of asthma patients: adjustment to rehabilitation].

Despite current discussions promoting physical and sports activities in asthmatics, no studies have yet been done on the possible pathophysiological justifications for rehabilitation by sports programs. Consequently asthmatics are retrained in an empirical fashion and the assessment of these programs is subjective. The aim of this article is thus to review the different studies concerning the adjustment of asthmatics to muscular exercise and to deduce from these what could or should be the pathophysiological objectives of reconditioning protocols. The principal ideas which emerge from this study derive from three fundamental facts: 1) the training of asthmatics should be based on an individual approach since clinical severity leads to very unequal adaptations during muscular exercise; 2) it is advisable to strive against the declining physical fitness of the asthmatics, which is responsible for the accelerated functional deterioration, disturbances of psychomotor development and an increased risk of exercise-induce asthma; 3) the decrease of excessive exercise hyperventilation is, from the evidence, the greatest priority among the pathophysiological objectives, because hyperventilation is a principal cause implicated in the disturbance of cardiovascular adjustments to effort by heart-lung interaction.


[Pharmacology of nicotine].

Nicotine has a small molecular weight and is absorbed via the mucosa (Guccal or nasal), the pulmonary alveoli and the skin. The phenomenon of autotitration explains how a dependent smoker can unconsciously change his method of smoking to maintain a steady nicotine level. Nicotine leads to a liberation of catecholamines by acting on the nervous system through the intermediary of nicotine receptors. There is increased vigilance and powers of intellectual concentration, an awakening reaction and some anxiolytic and euphoriant effects. From the cardiac stand point there is an increased heart rate and blood pressure, as a result of the sympathomimetic effects. Elimination is via the kidneys as unchanged nicotine, cotinine and 1'-N-oxide of nicotine. Nicotine has an addictive action and is capable of inducing pharmacological dependency, tolerance and withdrawal syndrome in cases of abrupt cessation. A knowledge of the pharmacology of nicotine is important in the process of stopping smoking.


[Diffuse infiltrative lung diseases: histological support of elementary lesions observed on tomodensitometry].

High resolution computed tomography (TDM-HR) is now the technique of choice in the diagnosis and management of diffuse infiltrative lung disease (PID). After a brief review of the technique the authors describe the normal appearance; anatomical observations and the in vivo findings have shown that TDM-HR allow for the exploration of details of structure down to the second pulmonary lobule. Thus, through the alterations that are transmitted in the lobular area, and from its contents and its limits, PID has led to the elaboration of a new semeiology. The authors review the basic computed tomographic images and correlate these in each case with the histological evidence. The spatial distribution and the time sequence of the elementary images are the two other terms in the diagnostic equation of PID. The spatial distribution of several elementary images presents in TDM-HR a superior aetiological pointer to that which is furnished by thoracic radiographs; and the time sequence may furnish a useful indication as to the progress of the treated disease. Sarcoidosis, histiocytosis X, idiopathic interstitial fibrosis and lymphangitis carcinomatosis would serve as examples. Nevertheless, the authors point out that it would be dangerous during the period of evaluation to prematurely extend to all cases of PID conclusions which are only possible to make at present in a restricted number of disorders.


[Local immune response in allergic asthma].

The key issue in asthma research is allergen capture and presentation. An increase in understanding in this area may result in the development of new types of therapeutic drugs, although at present there remain a number of points to be elucidated. In this paper, we review recent research in this field. Allergens are small air-conducted soluble antigens which are capable of inducing a specific immune response characterized by a significant synthesis of IgE. The allergen passes through the bronchial epithelium and specialized antigen presenting cells (APC) capture and present the antigen to T-cells, causing their activation via an interaction with class II MHC molecules on the APC. Allergens are also capable of activating other cell types and the subsequent release of inflammatory mediators, chemoattractants and cytokines may result in bronchial inflammation which is one of the cardinal signs of asthma.


[Respiratory function in heroin addicts with or without HIV infection. Study of 107 cases with a 6-month follow-up of 36 subjects].

Both intravenous drug addiction (IVDA) and HIV infection can involve respiratory system. So, we have studied pulmonary function in 107 heroin abusers during deprivation to clarify the extent of these two factors respectively. Two groups were separated: 50 subjects without HIV infection (HIV-) and 57 seropositive subjects (HIV+) in early stage of the disease (mean CD4 lymphocytes: 457 +/- 61/mm3). 36 subjects have been investigated 6 months later to evaluate the reversibility of possible observed abnormalities. Altered pulmonary function was encountered similarly in HIV+ and HIV-. DLco was abnormal in 40% of cases both in HIV+ (mean DLco: 63.4 +/- 1.1% of predicted values) and HIV- (mean DLco: 65.4 +/- 1.5% pred); obstructive lung disease was present in 18% of HIV- (FEV1/VC: 63.8 +/- 2.5) and 9% of HIV+ (FEV1/VC: 61 +/- 3.6); restrictive lung disease was found more frequently (16% vs 10%) in HIV+ (FEV1/VC: 81.2 +/- 2.1, TLC: 72.4 +/- 3.6% pred) than in HIV- (FEV1/VC: 84.2 +/- 1.6, TLC: 71.2 +/- 0.9% pred). These abnormalities were not associated with significant arterial blood gas modifications. As a whole, DLco tend to improve in the two groups and this significantly for HIV+ (p less than 0.03). But for individuals initial DLco alteration was persistent in 68% of cases suggesting slow improvement. In conclusion, in this study HIV+ and HIV- IVDA were not different concerning pulmonary function. In this risk group, DLco itself had a poor specificity and only it follow-up may be of interest for pulmonary opportunistic infection screening.