Functional neurogenomic responses to acoustic threats, including a heterospecific referential alarm call and its referent, in the auditory forebrain of red-winged blackbirds.

In animal communication, functionally referential alarm calls elicit the same behavioral responses as their referents, despite their typically distinct bioacoustic traits. Yet the auditory forebrain in at least one songbird species, the black-capped chickadee Poecile atricapillus, responds similarly to threat calls and their referent predatory owl calls, as assessed by immediate early gene responses in the secondary auditory forebrain nuclei. Whether and where in the brain such perceptual and cognitive equivalence is processed remains to be understood in most other avian systems. Here, we studied the functional neurogenomic (non-) equivalence of acoustic threat stimuli perception by the red-winged blackbird Agelaius phoeniceus in response to the actual calls of the obligate brood parasitic brown-headed cowbird Molothrus ater and the referential anti-parasitic alarm calls of the yellow warbler Setophaga petechia, upon which the blackbird is known to eavesdrop. Using RNA-sequencing from neural tissue in the auditory lobule (primary and secondary auditory nuclei combined), in contrast to previous findings, we found significant differences in the gene expression profiles of both an immediate early gene, ZENK (egr-1), and other song-system relevant gene-products in blackbirds responding to cowbird vs. warbler calls. In turn, direct cues of threats (including conspecific intruder calls and nest-predator calls) elicited higher ZENK and other differential gene expression patterns compared to harmless heterospecific calls. These patterns are consistent with a perceptual non-equivalence in the auditory forebrain of adult male red-winged blackbirds in response to referential calls and the calls of their referents.

[Management of a case of unilateral exophthalmos due to an intraorbital lipofibroma at Kara teaching hospital in Togo]. / Prise en charge d'un cas d'exophtalmie unilatérale due à un lipofibrome intra-orbitaire au CHU de Kara au Togo.

In childhood, benign tumors are uncommon causes of exophtalmos. We report a case of intraorbital lipofibroma in an 11-year-old girl who presented with painless, progressive proptosis of the right eye over the preceding 6 months. Ultrasound had shown an extraconal intraorbital mass. Complete excision and pathologic examination were performed, revealing a lipofibroma with no signs of malignancy This case report is notable due to the rarity of the condition.

[Bilateral simultaneous central retinal artery occlusion revealing giant cell arteritis]. / Occlusion bilaterale et simultanee de l'artere centrale de la retine revelatrice d'une maladie de Horton.

AIM: To point out the importance of the early diagnosis of giant cell arteritis (GCA) (Horton's disease). MATERIALS AND METHODS: a case report of a sudden bilateral blindness that had revealed GCA. CASE REPORT: A 68-year old female patient with a history of elevated blood pressure and diabetes mellitus type 2, was examined in emergency for a right painful headache developed one week previously. In ophthalmological examination, her BCVA was 0.9 and P2 in both eyes. Diagnosis of Horton's disease was not initially done in spite of elevated erythrocytes sedimentation rate (ESR) at 30 mm, protein C reactive (CRP) at 19 mg/l. The patient consulted seven weeks later in emergency for a sudden bilateral blindness associated with severe headache, recent asthenia, and limping of the lower jaw. At that time, visual acuity was reduced to light perception in both eyes whereas ophthalmoscopy revealed a bilateral central retinal artery occlusion (CRAO). ESR was 74 mm and CRP 233 mg/I. Temporal artery biopsy confirmed the diagnosis of GCA. The patient was treated with systemic steroids without visual recovery. CONCLUSION: This case outlines the importance of the early diagnosis of GCA in order to make possible to start treatment before the occurrence of irreversible complications.

Ossifying fibroma of the maxillary sinus at the Kara (Togo) Teaching Hospital.

INTRODUCTION: Ossifying fibroma of the jaw is a benign tumorous disease, somewhat rare and aggressive. It frequently targets the mandible, but seldom the maxillary. CASE STUDY: The present study reports the first case of left maxillary sinus fibroma treated at the Kara Teaching Hospital in North Togo. It occurred in a 29-year-old patient who experienced slow-growing tumefaction of the left maxillary sinus, resulting in deformation of the left side of the face in the maxillary region and ipsilateral nasal obstruction. Orthopantomography showed a displacement of teeth 21, 22, and 23 with an abnormal degree of opacity at the dental roots. The CT scan of the nose and sinuses revealed a tumorous lesion of expanding bony density increasing in volume at the outer wall of the left maxillary sinus, of regular shape that contained microscopic calcifications, extending into the ipsilateral orbital floor and pushing the surrounding soft tissues forward without invading them. The histopathological examination of the tumor confirmed the diagnosis of ossifying fibroma. DISCUSSION: Ossifying fibroma or fibrous osteoma is a rare and benign lesion developing insidiously with a polymorphous aspect. Of unknown etiology, most frequently located in the mandible, it is differentiated from other types of fibroma in its clinical, radiological, and histological aspects. However, only examination of the gross specimen can provide the final diagnosis. Treatment requires surgery. CONCLUSION: Surgical treatment entailed the complete macroscopic enucleoresection. Recovery has been favorable at 2 years of follow-up.

[Imflammatory myofibroblastic tumour of nose and paranasal sinuses in a little girl of 7-year-old]. / Tumeur myofibroblastique inflammatoire endonasale chez une fillette de 7 ans.

Inflammatory myofibroblastic tumours (IMTs) are clinical and pathological distinct entities with controversial biological entities. IMTs have been described in the lungs, abdomen, retroperitoneum and extremities but rarely in the head and neck region. This case report corresponds to an IMT of the nose and the paranasal sinuses in a little girl of 7 years of age. The computed tomography scan showed an expanding tumoral process without skull destruction. First case report in the west African region, this observation describes the treatment instituted according to the possible care in our medical area, and the treatment when the patient was referred to a centre with efficient technical platform. This case underlines the aggressiveness of this type of tumour: an invasive tumour with local-regional extension and high recurrence potential. Currently, after 2 years, the tumoral process is considered cured after several radical surgical excisions.

Global distribution of neutrons from Mars: results from Mars odyssey.

Global distributions of thermal, epithermal, and fast neutron fluxes have been mapped during late southern summer/northern winter using the Mars Odyssey Neutron Spectrometer. These fluxes are selectively sensitive to the vertical and lateral spatial distributions of H and CO2 in the uppermost meter of the martian surface. Poleward of +/-60 degrees latitude is terrain rich in hydrogen, probably H2O ice buried beneath tens of centimeter-thick hydrogen-poor soil. The central portion of the north polar cap is covered by a thick CO2 layer, as is the residual south polar cap. Portions of the low to middle latitudes indicate subsurface deposits of chemically and/or physically bound H2O and/or OH.

Evidence that pcpA encodes 2,6-dichlorohydroquinone dioxygenase, the ring cleavage enzyme required for pentachlorophenol degradation in Sphingomonas chlorophenolica strain ATCC 39723.

An enzyme that catalyzes an Fe2+-dependent reaction of 2, 6-dichlorohydroquinone with O2 has been isolated from Sphingomonas chlorophenolica sp. strain ATCC 39723, a soil microorganism capable of complete mineralization of pentachlorophenol. The product of the reaction is too unstable to allow spectroscopic characterization, but is apparently negatively charged and retains the two chlorine atoms of the substrate. The enzyme was partially sequenced using electrospray LC-MS, and one peptide was used to search the NCBInr database. This peptide matched a part of PcpA, a protein of unknown function that is induced in S. chlorophenolica in response to pentachlorophenol. Several other peptides could also be mapped onto the sequence of PcpA, suggesting that the enzyme is encoded by pcpA. PcpA has low but significant sequence similarity to an unusual class of extradiol dioxygenases. On the basis of the sequence analysis, the Fe2+ and O2 dependence of the enzyme, and the characteristics of the product, the enzyme is proposed to be a 2,6-dichlorohydroquinone dioxygenase. The position of ring cleavage has not yet been identified.

Mechanistic consequences of replacing the active-site nucleophile Glu-358 in Agrobacterium sp. beta-glucosidase with a cysteine residue.

Retaining glycosidases achieve the hydrolysis of glycosidic bonds through the assistance of two key active-site carboxyls. One carboxyl functions as a nucleophile/leaving group, and the other acts as the acid-base catalyst. It has been suggested that a cysteine residue could fulfil the role of the active site nucleophile [Hardy and Poteete (1991) Biochemistry 30, 9457-9463]. To test the validity of this proposal, a kinetic evaluation was conducted on the active-site nucleophile cysteine mutant (Glu-358-->Cys) of the retaining beta-glucosidase from Agrobacterium sp. The Glu-358-->Cys mutant was able to complete the first step (glycosylation) of the enzymic mechanism, forming a covalent glycosyl-enzyme intermediate, but the rate constant for this step was decreased to 1/10(6) of that of the native enzyme. The subsequent hydrolysis (deglycosylation) step was also severely affected by the replacement of Glu-358 with a cysteine residue, with the rate constant being depressed to 1/10(7) or less. Thus Cys-358 functions inefficiently in both the capacity of catalytic nucleophile and leaving group. On the basis of these results it seems unlikely that the role of the active-site nucleophile in retaining glycosidases could successfully be filled by a cysteine residue.

Positioning the acid/base catalyst in a glycosidase: studies with Bacillus circulans xylanase.

The mechanism of action employed by a glycosidase is dictated, in part, by the distance between the two catalytic carboxylic acids. In the retaining endo-beta-1,4-xylanase from Bacillus circulans, this critical distance (approximately 5.5 A) has been altered by mutagenesis of the putative acid/base catalyst Glu172. An increase in the separation (Glu172Asp) resulted in a 400-fold decrease in the k(cat) value for xylan hydrolysis. By contrast, a decrease in the separation, achieved by the selective carboxymethylation of the Glu172Cys mutant, caused only a 25-fold reduction in the rate of xylan hydrolysis. Altering the length of the acid/base catalyst had a less detrimental effect on the hydrolysis of aryl xylobiosides, with k(cat)/Km values being reduced only 3-23-fold relative to the wild-type enzyme. Complete removal of the carboxyl group had a more dramatic effect. The Glu172Cys and Glu172Gln mutants exhibited no measurable activity on xylan or phenyl xylobioside, substrates which require acid catalysis. However, these mutants were capable of hydrolyzing aryl xylobiosides with relatively good leaving groups (pKa < 5.5), which need little protonic assistance. The addition of sodium azide caused significant rate increases for the hydrolysis of 2,5-dinitrophenyl beta-xylobioside (pKa = 5.15) by Glu172Cys and Glu172Gln. Thus, the absence of an acid/base catalyst can be partially compensated for by the addition of an anionic nucleophile. These results are consistent with Glu172 functioning as the acid/base catalyst in B. circulans xylanase and emphasize the functional importance of the carboxyl group found at this position.

Effects of both shortening and lengthening the active site nucleophile of Bacillus circulans xylanase on catalytic activity.

The relative positioning of the two carboxyl groups at the active site of glycosidases is crucial to their function and the mechanism followed. The distance between these two groups in Bacillus circulans xylanase has been modified by mutagenesis of the catalytic nucleophile Glu78. An increase in the separation (Glu78Asp) results in a large (1600-5000-fold) reduction in the rate of the glycosylation step, but little change in the extent of bond cleavage or proton donation at the transition state. A decrease in the separation was achieved by selective carboxymethylation of the Glu78Cys mutant. This modified mutant was only 16-100-fold less active than wild-type enzyme, and its transition state structure was similarly unchanged. Complete removal of the carboxyl group (Glu78Cys) resulted in a mutant with no measurable catalytic activity. Furthermore, it did not even undergo the first step, glycosylation of the active site thiol. These results confirm the importance of precise positioning of the nucleophile at the active site of these enzymes.

A comparison of the analgesic and respiratory effects of epidural nalbuphine or morphine in postthoracotomy patients.

This randomized, double-blind study compared the analgesic and respiratory effects of lumbar epidural morphine 5 mg, nalbuphine 10 mg, and nalbuphine 20 mg in repeated doses in patients after thoracotomy; the first dose was administered intraoperatively. Pre-and postoperative monitoring included continuous pulse oximetry, respiratory inductance plethysmography, and repeated arterial blood gas analysis. Postoperatively, visual analogue pain scores, somnolence scores, respiratory rate, and arterial blood gases were determined for 16 h. Preoperatively, episodes of apnea were common during sleep but were not associated with low hemoglobin oxygen saturation or increased arterial carbon dioxide tension (PaCO2). During sleep, some otherwise normal patients had increased PaCO2, and 2 of 15 patients had episodes of hemoglobin oxygen saturation of less than 90%. Postoperatively, 1 and 2 h after arrival in the recovery room, patients who received morphine had lower pain scores than did those who received nalbuphine 10 or 20 mg (P less than 0.05). All 6 patients who received morphine had satisfactory analgesia. Two of 4 patients who received nalbuphine 10 mg and all 5 who received nalbuphine 20 mg were withdrawn from the study because of inadequate analgesia (morphine vs. nalbuphine 10 mg, not significant; morphine vs. nalbuphine 20 mg, P less than 0.01). Two patients who received morphine had persistently increased PaCO2 postoperatively. Two patients who received morphine had episodes of apnea and slow respiratory rate, which were most frequent 6 h after arrival in the recovery room. We conclude that lumbar epidural nalbuphine does not provide adequate analgesia after thoracotomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Lumbar epidural fentanyl infusions for post-thoracotomy patients: analgesic, respiratory, and pharmacokinetic effects.

Ten patients undergoing a thoracotomy were studied for 24 hours postoperatively to determine the effects of a continuous lumbar epidural fentanyl infusion on postoperative pain, arterial blood gases (ABG), respiratory pattern (respiratory inductive plethysmography, RIP), and fentanyl plasma concentration (CONC). Patients served as their own controls because RIP and ABG data were obtained the night prior to surgery during sleep. Epidural fentanyl was administered as a bolus of 1.5 micrograms/kg followed by an infusion of 1.0 micrograms/kg/h started 1 hour after induction. Insufficient analgesia was treated with a bolus of 0.5 micrograms/kg and an infusion increase of 0.25 micrograms/kg/h. Postoperative assessment included RIP, ABG, CONC, and visual analog pain score (PS). The average infusion rate postoperatively was 1.47 +/- 0.08 micrograms/kg/h (114.3 +/- 8.3 micrograms/h). A mean PS of 2.1 +/- 0.3 was achieved; however, there was a delay in attaining this. There was no significant incidence postoperatively of apnea or slow respiratory rate. A significant but clinically insubstantial increase in PaCO2 and decrease in pH occurred. A steady state CONC of approximately 2.0 ng/mL was reached after 9 hours. The PS correlated with CONC in half the patients (0.60 less than r less than 0.86), indicating a systemic component may have contributed to the analgesic effect.