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Notes: Abstract Four cases of microcystic adenoma of the pancreas, including ultrasonographic (US) and computed tomographic (CT) data, are described. These tumors generally present as large, well-delimited pancreatic masses whose multicystic nature is readily evidenced on postcontrast CT scans. While the presence of cysts less than 2 cm in diameter and a central, star-like calcification are very specific, the frequency of atypical forms generally justifies exploratory surgery.

Notes: Abstract The evoked expression of the immediate early gene (IEG)-encoded proteins c-Fos and Krox-24 was used to monitor spinal visceronociceptive processing that results from cyclophosphamide cystitis in behaving rats. Animals received a single dose of 100 mg/kg i.p. of cyclophosphamide and survived for 30 min to 5 h. Longer survival times were not considered because of ethical considerations. Cyclophosphamide-injected animals developed characteristic behavioral signs in parallel with development of bladder lesions and spinal evoked expression of IEG-encoded proteins. Histological examination of the urinary bladder was used to evaluate the degree of cystitis and as a criterion for selection of groups of animals to be quantitatively analyzed. Controls consisted of freely behaving animals including control (uninjected), sham (saline-injected) or diuretic (furosemide-injected) animals. Behavioral modifications consisted of lacrimation, piloerection, assumption of a peculiar “rounded-back” posture, which was accompanied by head immobility and various brief “crises” (tail hyperextension, abdominal retractions, licking of the lower abdomen, backward withdrawal movements). Abnormal behaviors, which first appeared (lacrimation, piloerection) at the end of postinjection hour 1, progressively increased in severity (rounded-back posture) over the following 90 min to reach a plateau at about postinjection hour 2; the rounded-back posture was maintained up to time of death. Histological modifications of bladder tissue were assessed using a 4-grade scale in a blind setting. The 1st grade consisted of control or sham animals with no bladder lesion; 2nd grade, animals with simple chorionic edema; 3rd grade, animals with chorionic edema associated with mucosal abrasion, fibrin deposit, and onset of polymorphonuclear leukocyte infiltration; 4th grade, animals with complete cystitis corresponding to an increase in severity and spread of all the signs of cystitis described above plus petechial hemorrhage. Simple chorionic edema was observed from 30 min to 3 h post-injection, but with a progressive increase in severity over time. Edema accompanied by epithelial abrasion was observed for animals that survived 3–4 h postinjection; complete inflammation was observed in animals that survived 4–5 h postinjection. The study of c-Fos- and Krox-24-encoded protein expression demonstrated that few lumbosacral spinal areas were specifically involved in the processing of visceral inputs in response to bladder stimulation. These areas were the parasympathetic column (SPN), the dorsal gray commissure (DGC as the caudal extent of lamina X), and superficial layers of the dorsal horn. Differential basal and evoked labeling between c-Fos and Krox-24 allowed a functional distinction between these spinal subregions: Krox-24 was an indicator of the first signs of inflammation (simple chorionic edema); c-Fos was an indicator of more pronounced impairments. DGC, which displayed a high level of basal Krox-24 expression and in which both Krox-24 and c-Fos were evoked in relation to disease evolution, probably codes inputs from both physiological (progressive bladder filling) and all types of pathological (inflammatory processes, overdistension) conditions. SPN, which, except for basal Krox-24 expression, responded like DGC and contains preganglionic motor cells, probably codes inputs involved in eliciting motor activity that results in bladder emptying as needed from natural filling and/or pathological situations. Laminae I and II, which responded like DGC and SPN with respect to Krox-24 expression, may code inputs from physiopathological changes of the bladder, though lamina I would be primarily involved in pain processing as it was the only region in which c-Fos expression increased during abrasion and complete inflammation. The cyclophosphamide-cystitis model has the following unique features compared with other visceral models: first, the stimulus is a “pure” visceral one, confined to one viscus (bladder; no somatic stimulation is induced by either introducing a stimulating device or from surgical wounds, and no anesthesia is required); second, it is the exact replica of a human disease, and its evolution can be efficently monitored through behavioral and histological observations; third, it can be used in behaving animals without departing from ethical rules.

Notes: Abstract The evoked expression of the immediate-early gene-encoded proteins c-Fos and Krox-24 was used to study activation of mesodiencephalic structures as a function of the development of cyclophosphamide (CP) cystitis in behaving rats. This article is the third of a series and completes previously published data obtained at both spinal and hindbrain levels. CP-injected animals received a single dose of 100 mg/kg i.p under transient volatile anesthesia and survived for 1–4 h in order to cover the entire postinjection period during which the disease develops. Survival times longer than 4 h were not used owing to ethical considerations. Results from CP-injected groups are compared with those from either noninjected controls or saline-injected, animals having survived for the same times as CP-injected ones. Quantitative results come from c-fos expression. At mesodiencephalic levels a high and widespread basal c-fos expression was observed in control animals; maximum staining was observed at the midthalamic level. Four groups of nuclei were identified with regard to the density of staning. The first group included nuclei showing clustered, intensely labeled cells; these areas were restricted in extent and related to the maintenance of circadian rythms (intergeniculate leaf, suprachiasmatic nucleus, dorsal parts of either paraventricular thalamic nuclei or central gray), sleep-arousal cycle (supramamillary nucleus), or changes in arterial pressure (laterodorsal tegmental nucleus). The second group included nuclei showing scattered, moderately labeled cells; these areas were widespread at all rostrocaudal levels and related to either autonomic/neuroendocrine regulations (central gray, lateral and the caudal part of the bulbar reticular formation. In contrast, more rostral subtelencephalic levels contain a variety of areas, in which maximal reaction precedes the complete development of cystitis and appears to be more involved in vegetative functions.

Notes: Abstract The evoked expression of the immediate early gene encoded proteins c-Fos and Krox-24 was used to study activation of hindbrain neurons as a function of the development of Cyclophosphamide (CP) cystitis in behaving rats. CP-injected animals received a single dose of 100 mg/kg i.p. under transient volatile anesthesia and survived for 1 to 4 h in order to cover the whole postinjection period during which the disease develops. CP-injected groups included: (1) animals with minor simple chorionic edema, an early characteristic of inflammation (1 h postinjection); (2) animals with well developed simple chorionic edema (2 h postinjection); (3) animals with mild inflammation (chorionic edema accompanied by epithelial cleavage; 3 h postinjection); and (4) animals with complete inflammation (4 h postinjection). In addition to onset of chorionic edema, the earliest postinjection period also included the general aspects of the nervous reaction consecutive to the injection process (handling, transient volatile anesthesia and postanesthesia awakening, abdominal pinprick, CP blood circulating effects). Controls included both noninjected animals and saline injected animals surviving for the same times as CP injected ones. Quantitative results come from c-Fos expression. It has been shown that: (1) saline injection is a significant stimulus for only nucleus O and central gray pars alpha and nucleus medialis of the dorsal vagal complex; (2) all structures driven by CP injection (nucleus O and central gray pars alpha, locus coeruleus, Barrington's nucleus and parabrachial area mostly in its ventral and lateral subdivisions, dorsal vagal complex, ventrocaudal portion of lateral bulbar reticular formation) responded vigorously shortly after injection, but only two (dorsal vagal complex, ventrocaudal portion of lateral bulbar reticular formation) showed increased or renewed activity when cystitis completely developed, i.e., when noxious visceral inputs reached highest levels. Regarding the sequential activation of these structures in relation to postinjection time, evidence is given that: (1) a large variety of hindbrain structures are differentially involved in either the general reaction consecutive to the injection process or to various degrees of cystitis; (2) these structures extend from the brain spinal cord to the pons mesencephalon transitional junction levels; (3) the two structures most powerfully driven by visceronociceptive inputs are also the most caudal ones, being located at the brain spinal cord junction level; and (4) the dorsal vagal complex could be the main hindbrain visceral pain center, with three particular subdivisions, the nucleus medialis, nucleus commissuralis, and ventralmost part of area postrema, being involved.

Notes: Abstract  This article is the fifth of a series aimed at mapping brain activities as they result from the development of cyclophosphamide (CP) cystitis in behaving rats using c-fos and Krox-24 expression. The inactive hepatic metabolites of CP are metabolized in the kidney to produce acrolein, which generates cystitis. Data come from animals which were injected once i.p. with either 1 ml saline (sham) or 100 mg/kg CP in 1 ml saline under transient volatile anesthesia and which behaved freely for 1–4 h postinjection, 4 h being the minimum time for cystitis to completely develop. Survival times longer than 4 h were not studied owing to ethical considerations. The first 2 h postinjection cover a period of time over which inputs of multifactorial origin (stress and pain due to the intraperitoneal injection process, possible effects due to the presence of hepatic CP metabolites in blood, cystitis onset) interact in an indistinguishable way; the last 2 h are more cystitis specific as the other effects have vanished. Complete screening of telencephalic levels has been performed. These data complete previously published data at both spinal and subtelencephalic levels. Of all the telencephalic structures, only the bed nucleus of the stria terminalis in the dorsal part of its lateral division (BSTLd) and, to a lesser degree, the nucleus centralis of the amygdala, mostly in its caudal portion (cCeA), appeared to be significantly driven over the most specific cystitis period. Both of these structures had related, but not identical patterns of expression. They both reacted shortly after CP injection, but, while cCeA maintained its activity throughout cystitis development, BSTLd showed a rebound, reaching a peak value when cystitis was fully developed. Both of these areas are the only telencephalic areas to contain high PACAP38 immunoreactivity. This is evidence that, (1) both the BSTLd and cCeA could be the most rostral areas that visceronociceptive inflow would reach when cystitis genesis is under way, and (2) PACAP38 could be one of the neurochemical agents involved in telencephalic visceronociceptive processing. From our complete mapping of brain activities under a fully developed cystitis situation (4 h postinjection), it appears that the activities in BSTLd and cCeA are concomittant with those of both the dorsal vagal complex (DVC), paratrigeminal nucleus (PaT), and the ventrocaudal bulbar reticular formation (vcBRF) at brainstem levels, suggesting they all form the main part of the neural network that subserves the central processing of cystitis-related inputs, comprising pain and associated pseudoaffective responses. Both the DVC and BSTLd, which are the most powerfully driven areas, would be particularly important in such a way. The origin of these activities should be found in both vagal (as sensed through PaT activity) and spinal (pelvic) influences. This network profoundly differs from those reported for painful situations, either somatic or visceral, which controversally accompany positive cardiac inotropism.

Notes: Abstract Benign fibrous mesothelioma of the pleura is a rare tumor of mesodermal origin. We describe the MR findings in three pathologically proven cases. All three tumors were imaged by MR as well-circumscribed lesions with smooth margins in contact with the pleura, but without chest wall invasion. Their low signal intensity on T1-and T2-weighted sequences reflect their fibrous nature. In one case a pedicle connecting the tumor to the chest wall was visualized on a sagittal MR scan. In two cases gadolinium-enhanced T1-weighted gradient echo sequences revealed intense contrast uptake by the tumor correlated with the intratumoral hypervascularization noted by histologic examination. Although the number of cases presented is small, MR seems to be the most accurate imaging modality in the assessment of the diagnosis.

Notes: A case study of sinus histiocytosis of Rosai-Dorfman (SH) clinically limited to the skin is presented with immunohistochemical study of the infiltrate, in both paraffin and cryostal sections. Factor XIIIa, a dendrocyte marker, was demonstrated in the cytoplasm of histiocytes. This feature had not been previously reported in this disease. In addition, the cells expressed S100 protein, CD4, CD la, GD68, and GD11c. This immunophenotyping study suggests that SH could affect the antigen-presenting activity of Factor XIIIa cells, i.e., the skin dermal dendrocyte.

Notes: Salivary cryptococcosis was disclosed al autopsy in an AIDS patient with disseminated C. neoformans infection. H & E staining was not suitable to demonstrate the occurrence of C. neoformans in many tisues: Alcian blue gave the best results.

Notes: In the Mediterranean basin area, visceral leishmaniasis is an endemic disease caused by Leishnninia donovant infantum. This study describes the clinical and pathological features of one patient with AIDS who had oral (tonsillar) leishmaniasis, caused by a viscerotropic zymodcme, concurrent with a Kaposi's sarcoma and with a CMV infection.

Notes: Abstract The majority of endodermal cysts occur in the cervicothoracic spine, ventral to the cord. Intracranial locations are rare. We report a case involving the foramen magnum in a 14-year-old child, which was an incidental finding following a traumatic head injury. A review of the literature revealed six other cases involving this same location. These lesions are asymptomatic for a long time, and may cause brain stem medullary compression. Treatment is surgical. Effective simple removal can be achieved by a posterior approach.