Acinetobacter baumannii colonization in ventilated preterm infants

The role of Acinetobacter baumannii in infections in ventilated preterm infants was evaluated in 15 colonized infants (11 male, 4 female) in a pediatric intensive care unit. These cases were randomly matched by birth weight and gestational age with ventilated non-colonized controls (8 male, 7 female). Case records were reviewed for signs and symptoms of infection. Colonized infants were ventilated significantly longer (p < 0.05) than controls, and had body temperatures of > 37 degrees C for a significantly longer period of time (p < 0.05). No other parameter of infection differed significantly between the groups. The duration of intensive care treatment did not differ between cases and controls, nor did the weight gain during intensive care treatment. No fatalities occurred in either group.

Community children's nursing: an evaluative framework

There are alternative models of community children's nursing (CCN). A number of suitable criteria have been identified for evaluating CCN. Which criteria are given most weight depends crucially on the perspective of different stakeholders and the power that they hold. A framework for evaluating CCN is developed.

Candida infection in very low birth-weight infants: outcome and nephrotoxicity of treatment with liposomal amphotericin B (AmBisome)

Systemic fungal infection occurs in 2 to 4.5% of very low birth-weight (VLBW) infants (< 1,500 g) and may be fatal in 25 to 54%. Candida sp. is the major pathogen and amphotericin B the treatment of choice. To reduce side effects and optimize drug action, a formulation of amphotericin B encapsulated in liposomes (AmBisome) has been introduced. Data on 21 VLBW infants who received a full course of AmBisome was collected and its toxic effects with emphasis on nephrotoxicity and hypokalemia assessed. The median gestational age was 25 weeks (range 23-31) with a median birth-weight of 730 g (range 450-1,370). Antifungal therapy was started at a median age of 13 days (range 1-49). The median dose given was 2.6 mg/kg/day (range 1-5), and the median duration of therapy was 28 days (range 11-79), corresponding to a median cumulative dose of 71 mg/kg (range 12-271). Hypokalemia (< 3.0 mmol/l) was observed in 30% before, and 15% during AmBisome treatment. Twenty-one days after the termination of therapy, hypokalemia was not present in any patient. Median maximum daily potassium supplementation did not exceed doses usually recommended for VLBW infants. The median of the maximum creatinine levels before treatment was 121 mumol/l (range 71-221) and fell to 68 mumol/l (range 31-171) during treatment and 46 mumol/l (range 26-62) 21 days after the termination of therapy. All patients treated with AmBisome eradicated fungi and recovered clinically. AmBisome showed no certain nephrotoxicity in VLBW infants in this study.

Fetal parvovirus B19 infection and meconium peritonitis

A 33-year-old primigravida at 26 weeks gestation presented with fetal hydrops and fetal anemia following prior parvovirus B19 infection. The fetus required two intrauterine transfusions of packed red cells. At 35 weeks gestation, a cesarean section was performed for obstetric reasons. As a consequence of a prenatal bowel perforation, the neonate developed meconium peritonitis, for which she needed laparotomy. This case demonstrates that there may be an association between intrauterine parvovirus infection and meconium peritonitis, the latter possibly caused by vascular injury in fetal life.

[Esophageal perforations and ruptures: a plea for conservative treatment]

OBJECTIVES

To identify the determinants and results on conservative management of oesophageal perforations and ruptures.

METHODS

Retrospective clinical review of 34 consecutive patients (mean age: 62 years) treated for cervical (n = 10) or thoracic (n = 24) oesophageal disruption between 1985 and 1996. Causes were: spontaneous rupture (n = 10), instrumental perforation (n = 16), alimentary foreign body (n = 6), and blunt (n = 1) or penetrating trauma (n = 1). The diagnostic delay exceeded 24 hours in 15 cases.

RESULTS

A nonoperative management was achieved in 8 patients with no mortality. A conservative surgical treatment was attempted in 23 patients, primary repair in 21 and open drainage in 2, with a 17.4% mortality. Resection (n = 2) or exclusion (n = 1) was performed in 3 patients with no early mortality, but one of them died as result of the subsequent reconstructive operation to restore oesophageal continuity. Overall morbidity was linked to the spontaneous cause of the perforation. Outcome of patients undergoing primary repair was not influenced by the diagnostic delay nor the surrounding sepsis.

CONCLUSION

Conservative management should be advocated for the treatment of oesophageal perforations and ruptures, even in case of delayed diagnostiqiagnosis, regardless of the surrounding sepsis and cause of disruption.

NEAR's flyby of 253 mathilde: images of a C asteroid

On 27 June 1997, the Near Earth Asteroid Rendezvous (NEAR) spacecraft flew within 1212 kilometers of asteroid 253 Mathilde. Mathilde is an irregular, heavily cratered body measuring 66 kilometers by 48 kilometers by 46 kilometers. The asteroid's surface is dark (estimated albedo between 0.035 and 0.050) and similar in color to some CM carbonaceous chondrites. No albedo or color variations were detected. The volume derived from the images and the mass from Doppler tracking of the spacecraft yield a mean density of 1.3 +/- 0.2 grams per cubic centimeter, about half that of CM chondrites, indicating a porous interior structure.

Bronchiolitis obliterans with organizing pneumonia and cold agglutinin disease associated with phenytoin hypersensitivity syndrome

Phenytoin hypersensitivity syndrome (PHS) is a rare delayed hypersensitivity reaction which occurs following exposure to phenytoin sodium. Pulmonary involvement is uncommonly described. Herein is reported the first case of histopathologic bronchiolitis obliterans organizing pneumonia (BOOP) found on open-lung biopsy in a patient with severe PHS. New onset, clinically significant, cold agglutinin disease was also documented. Hemodynamic parameters mimicking sepsis were present in the absence of significant clinical infection. Rapid, dramatic improvement followed high-dose steroid therapy.

X-ray structure of 5-aminolaevulinate dehydratase, a hybrid aldolase

5-Aminolaevulinate dehydratase (ALAD) is a homo-octameric metallo-enzyme that catalyses the formation of porphobilinogen from 5-aminolaevulinic acid. The structure of the yeast enzyme has been solved to 2.3 A resolution, revealing that each subunit adopts a TIM barrel fold with a 39 residue N-terminal arm. Pairs of monomers wrap their arms around each other to form compact dimers and these associate to form a 422 symmetric octamer. All eight active sites are on the surface of the octamer and possess two lysine residues (210 and 263), one of which, Lys 263, forms a Schiff base link to the substrate. The two lysine side chains are close to two zinc binding sites one of which is formed by three cysteine residues (133, 135 and 143) while the other involves Cys 234 and His 142. ALAD has features at its active site that are common to both metallo- and Schiff base-aldolases and therefore represents an intriguing combination of both classes of enzyme. Lead ions, which inhibit ALAD potently, replace the zinc bound to the enzyme's unique triple-cysteine site.

[Status epilepticus: indications for emergency EEG]

EEG is a major tool in convulsive status epilepticus. Several techniques may be used, including conventional or digitized EEG using 4, 8, 10 or 16 channels, continuous monitoring with or without simultaneous video recording, and cerebral function monitor. During the first phase, in the emergency ward, EEG may be useful in severe convulsive status epilepticus to assess further evolution and/or prognosis. However, rapid control of seizure at this phase is the primary goal, and optimization of EEG availabilities may lead to more systematic indications. After adequate control of seizures, EEG is mandatory in the following situations: i) a difficult-to-control convulsive status epilepticus, with a high risk of subsequent evolution towards subtle status epilepticus; ii) a resistant status epilepticus which needed high dose of sedatives drugs and/or curarization, to evaluate the level of anaesthesia and to watch for recurrence of epileptiform abnormalities; iii) a permanent, unexplained impairment of consciousness which followed an apparently successful treatment, to detect non convulsive status epilepticus; 4. a doubtful clinical diagnosis, to confirm pseudo-status epilepticus.

Gastric emptying time is faster in cystic fibrosis

BACKGROUND

The high energy requirements in cystic fibrosis (CF) increase the likelihood of malnutrition. Delayed mouth-to-cecum transit times have been reported and raise the possibility that abnormalities of gastric function in CF contribute to reduced food intake. The aims of this project were to document solid-phase gastric emptying times in young people with CF and age- and sex-matched healthy controls, and to investigate whether delayed gastric emptying contributes to suboptimal energy intakes.

METHODS

Nineteen subjects with CF, mean age 12.6 years (11 girls and 8 boys), and 17 control subjects, mean age 12.8 years (9 girls and 8 boys), were studied. Energy intake was assessed by means of a 4-day weighed food record. Fecal fat excretion was determined from a 3-day stool collection. Gastric emptying was assessed with a standard test meal of pancakes labeled with 99mTc-macroalbumin aggregates. The half emptying time of solids from the stomach was recorded.

RESULTS

The mean solid-phase gastric emptying time was significantly faster in the CF subjects compared with normal, healthy, age- and sex-matched control subjects (53 min vs. 72.2 min, p < 0.05). Energy intakes, measured as the percentage of the recommended energy intake for age and sex, were greater in the CF subjects than in the control subjects (115% vs. 89%, p < 0.01), whereas the mean % FFE for the CF subjects was 9.9%. CF subjects with longer gastric emptying times also had lower relative energy intakes (r = -0.50, p < 0.05).

CONCLUSION

Gastric emptying time in healthy subjects with CF is rapid. Faster solid-phase gastric emptying times may be secondary to high-fat, high-energy intakes and may represent a survival advantage.

Correlation between binding affinities of C21 steroids for the maturation-inducing steroid membrane receptor in spotted seatrout ovaries and their agonist and antagonist activities in an oocyte maturation bioassay

The relative binding affinities of steroids for the maturation-inducing steroid (MIS) plasma membrane receptor in spotted seatrout (Cynoscion nebulosus) ovaries were compared to their relative potencies in inducing final oocyte maturation (FOM) of seatrout oocytes in vitro. The MIS receptor is specific for C21 steroids (pregnenes) lacking ketone or hydroxyl (OH) groups at the 11 position. The addition of single OH groups at the 17, 20, or 21 positions and two OHs at the 17, 20 and at the 17, 21 positions of both progesterone and pregnenolone derivatives decreased binding affinity. In contrast, the combination of OH at the 20beta and 21 positions increased affinity, and greatest binding affinity for a progesterone derivative was observed with three OHs at positions 17, 20beta, and 21 (17,20beta,21-trihydroxy-4-pregnen-3-one; 20beta-S), the natural MIS in this species. Germinal vesicle breakdown (GVBD) bioassays showed that 1-min exposure to 290 nM 20beta-S or 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P) in vitro was sufficient to induce final maturation of follicle-enclosed oocytes of seatrout and a closely related species, Atlantic croaker (Micropogonias undulatus), whereas the other steroids tested were ineffective. 20Beta-S was more potent than 17,20beta-P in inducing GVBD after 1-min exposure at lower steroid concentrations (5 nM-100 nM), even though the follicular uptake of the two steroids was similar. Coincubation of seatrout oocytes for 1 min with other steroids at concentrations capable of displacing more than 80% of the bound 20beta-S from its receptor effectively blocked the induction of GVBD by 5 nM 20beta-S. The binding affinities of steroids for the MIS receptor correlated in general with either their agonist or their antagonist activities in the GVBD bioassays. These findings strongly support the concept that induction of FOM by the MIS in spotted seatrout is mediated solely through the ovarian plasma membrane 20beta-S receptor.

Modulation of stimulus-secretion coupling in single rat gonadotrophs

1. Exocytosis and intracellular [Ca2+] were determined simultaneously in single anterior pituitary gonadotrophs from ovariectomized female rats. Dispersed cells were cultured for 2-4 days with or without 0.2 nM oestradiol-17 beta (E2) before use. Cells were stimulated with either gonadotrophin releasing hormone (GnRH) or by membrane depolarization. Exocytosis was determined from the change in membrane capacitance (Cm) using the perforated-patch whole-cell recording technique. Intracellular [Ca2+] was measured using fura-2 fluorescence. 2. The exocytotic response to 1 nM GnRH was characterized by a wide spectrum of responses, ranging from exocytotic bursts to relatively slow, graded increases that were dependent on the evoked intracellular Ca2+ pattern. A kinetic model is presented that incorporates the observed steep dependence of exocytosis on measured intracellular [Ca2+]; simulated exocytosis reasonably approximated observed exocytotic responses, both kinetically and quantitatively. The model also suggests that the modulatory effects of E2 are brought about either by a change in the Ca2+ sensitivity of exocytosis or by a preferential clustering of docked-secretory granules close to sites of Ca2+ release. The results suggest that in gonadotrophs an oscillatory Ca2+ signal is sensed by the exocytotic apparatus in a modified form of digital encoding. 3. Exocytosis in E2-treated cells was 3-fold greater than in non-treated cells for GnRH-evoked secretion, and 38% greater for depolarization; however, there was no effect of E2 on the intracellular Ca2+ response to either stimulus. The results show that maximum expression of the effect of E2 on exocytosis requires activation of GnRH-dependent pathways.

Effect of single point mutations of the human tachykinin NK1 receptor on antagonist affinity

Molecular modelling and site-directed mutagenesis were used to identify eleven amino acid residues which may be involved in antagonist binding of the human tachykinin NK1 receptor. Recombinant receptors were expressed in mammalian cells using the Semliki Forest virus system. Wild type and mutant receptors showed similar expression levels in BHK and CHO cells, verified by metabolic labelling. Binding affinities were determined for a variety of tachykinin NK1 receptor antagonists in SFV-infected CHO cells. The binding affinity for GR203040, CP 99,994 and CP 96,345 was significantly reduced by mutant Q165A. The mutant F268A significantly reduced the affinity for GR203040 and CP 99,994 and the mutant H197A had reduced affinity for CP 96,345. All antagonists seemed to bind in a similar region of the receptor, but do not all rely on the same binding site interactions. Functional coupling to G-proteins was assayed by intracellular Ca2+ release in SFV-infected CHO cells. The wild type receptor and all mutants except A162L and F268A responded to substance P stimulation.

Spirochaeta smaragdinae sp. nov., a new mesophilic strictly anaerobic spirochete from an oil field

An obligately anaerobic spirochete designated strain SEBR 4228T (T = type strain) was isolated from an oil field of Congo, Central Africa. The strain grew optimally with a sodium chloride concentration of 5% (sodium chloride concentration) growth range 1.0-10%) at 37 degrees C (growth temperature range 20-40 degrees C) and pH of 7.0-7.2 (pH growth range pH 5.5-8.0). Strain SEBR 4228T grew on carbohydrates (glucose, fructose, ribose, D-xylose, galactose, mannitol and mannose), glycerol, fumarate, peptides and yeast extract. Yeast extract was required for growth and could not be replaced by vitamins. It reduced thiosulfate and sulfur, to H2S. Glucose was oxidised to lactate, acetate, CO2 and H2S in the presence of thiosulfate but in its absence lactate, ethanol, CO2 and H2 were produced. Fumarate was fermented to acetate and succinate. The G + C content of strain SEBR 4228T was 50%. Strain SEBR 4228T was spiral shaped measuring 5-30 by 0.3-0.5 micron and was motile with a corkscrew-like motion. Electron microscopy revealed the presence of periplasmic flagella in a 1-2-1 arrangement. Strain SEBR 4228T possessed features typical of the members of the genus Spirochaeta. 16S rRNA sequence analysis revealed that it was closely related to Spirochaeta bajacaliforniensis (similarity 98.6%). The lack of DNA homology with S. bajacaliforniensis (38%), together with other phenotypic differences, indicated that strain SEBR 4228T is a new species, which we have designated Spirochaeta smaragdinae. The type strain is SEBR 4228T (= DSM 11293).

[Pulmonary Wegener's disease mimicking tuberculosis]

We report a case of early Wegener's disease mimicking tuberculosis in a 36 year old man. Lungs are solely affected for 6 months. Unusual appearance of radiographic features with large apical excavations explain the delai for the diagnosis. We discuss morphological features in the lungs and kidney.

Thermotoga hypogea sp. nov., a xylanolytic, thermophilic bacterium from an oil-producing well

A new thermophilic, xylanolytic, strictly anaerobic, rod-shaped bacterium, strain SEBR 7054T, was isolated from an African oil-producing well. Based on the presence of an outer sheath (toga) and 16S rRNA sequence analysis data, this organism was identified as a member of the genus Thermotoga. Strain SEBR 7054T possessed lateral flagella, had a G + C content of 50 mol%, produced traces of ethanol from glucose but no lactate, and grew optimally in the presence of 0 to 0.2% NaCl at 70 degrees C. Its phenotypic and phylogenetic characteristics clearly differed from those reported for the five previously validly described Thermotoga species. Therefore, we propose that strain SEBR 7054T is a member of a new species of the genus Thermotoga, Thermotoga hypogea sp. nov. The type strain of T. hypogea is SEBR 7054 (= DSM 11164).

Renal biopsy collagen I mRNA predicts scarring in rabbit anti-GBM disease: comparison with conventional measures

Progressive loss of normal structure associated with scarring is the hallmark of chronic diseases of most organs. To test the hypothesis that measurement of interstitial collagen mRNA levels would be a useful index to predict future scarring, we developed an assay to quantitate alpha 1(I) procollagen mRNA factored for GAPDH mRNA using RT-PCR (the "CI:G ratio"). We first defined conditions under which the assay could be used for analysis of renal biopsy samples. The CI:G ratio was then used to determine whether mRNA measurements performed at an early stage of inflammation (day 7) in a model of anti-GBM disease in the rabbit would predict outcome at day 30 as measured by interstitial and glomerular scarring and renal cortical hydroxyproline accumulation. The predictive value of this assay was compared to functional (serum creatinine and urine protein:creatinine ratio) and histologic (glomerular and interstitial scoring) parameters also measured at day 7. We found that the CI:G ratio alone provided a sensitive and discriminating assay over a wide range of renal injury that predicted various parameters of scarring with an average coefficient of determination (r2) of 0.69. This predictive power was higher than that found for conventional measures, which tended to have good discriminatory capacity over limited ranges of renal injury. The CI:G ratio provided significant additional predictive power over and above that available from combinations of conventional functional or histologic parameters. We conclude that measurement of the CI:G ratio in biopsy samples deserves further assessment as a potentially useful quantitative predictor of outcome that could lead to improved clinical decision-making.

In vivo induction of murine cytokine production by carcinoembryonic antigen

Carcinoembryonic antigen (CEA) may promote experimental metastasis through production of cytokines. The effect of systemic CEA on the production of proinflammatory cytokines was investigated in mice and compared to levels induced by lipopolysaccharide (LPS). Serum concentrations of interleukin (IL)-6 peaked 1 h after an i.v. CEA injection of 40 microg/mouse to 37-54% of the maximal level induced by a 1 microg/mouse injection of LPS in both normal and immunoincompetent mice. The CEA induction of IL-6 was a specific response, because the peptide PELPK (the pentapeptide on CEA that is the ligand for the CEA receptor on Kupffer cells) conjugated to albumin induced 30% of the maximal CEA response for IL-6, whereas the specificity control PELGK-conjugated albumin did not. IL-1alpha and tumor necrosis factor (TNF)-alpha levels after i.v. injection of CEA were only 3-5% of those induced by LPS. The IL-6 responses of mice pretreated with 100 microg/kg genistein were decreased by more than 40%. However, genistein inhibited the TNF-alpha response to LPS by 46% but increased the CEA-induced response by 300%. When murine Kupffer cells were stimulated with LPS or CEA in vitro, LPS increased tyrosine phosphorylation of a Mr 30,000 protein, whereas CEA decreased phosphorylation of a Mr 60,000 protein and did not increase phosphorylation of the Mr 30,000 protein. Thus, i.v. CEA stimulates production of IL-6 and TNF-alpha after binding to Kupffer cells through signal transduction pathways that appear to be different from those stimulated by LPS.