Dual effects of 17beta-oestradiol on interleukin 1beta-induced proteoglycan degradation in chondrocytes

OBJECTIVE

To determine whether 17beta-oestradiol (E2) modulates interleukin (IL) 1beta-induced proteoglycan degradation in chondrocytes, and to analyse the part played by metalloproteinases (MMPs) in this process.

METHODS

Primary cultured rabbit articular chondrocytes were prepared and treated with 10 ng/ml IL1beta combined or not with 0.1-10 nM E2. Neosynthesised proteoglycans (PGs) were evaluated after incorporation of [(35)SO(4)]sulphate and further analysed after chromatography on a Sepharose 2B column. Chondrocyte mRNA levels of aggrecan, MMP-1, -3, -13, and tissue inhibitor of metalloproteinase-1 (TIMP-1) were studied by northern blot. MMP-1 activity was measured by zymography. MMP-1 gene transcription was studied by transient transfection of chondrocytes with an MMP-1-luciferase construct.

RESULTS

E2 modulated the IL1beta-induced total sulphated PGs in rabbit articular chondrocytes, which decreased as the E2 concentration was increased. At a low concentration (0.1 nmol/l) E2 counteracts the IL1beta-induced decrease in sulphated PG, while at high concentration (10 nmol/l) E2 enhances the IL1beta effects. A biphasic E2 effect was also observed on IL1beta-induced disaggregation of PG, 53-58 kDa gelatinolytic activity, and MMP-1, -3, and -13 mRNA levels. In contrast, E2 did not modify the level of aggrecan mRNA and had no effect on TIMP-1 mRNA expression. Finally, simultaneous addition of IL1beta and E2 (0.1-10 nmol/l) did not modify IL1beta-induced MMP-1-luciferase activity, suggesting that E2 effects probably occur at the post-transcriptional level of MMP gene expression.

CONCLUSION

Oestrogen concentration may have an inverse effect on IL1beta stimulated proteoglycan degradation and MMP production by chondrocytes.

Neonatal detection of the 35delG mutation of the GJB2 gene in families at risk for deafness

About half of congenitally deaf children that have a recessively inherited sensorineural deafness are born from normal-hearing parents and have no risk factor for hearing loss. Mutation 35delG in the connexin-26 gene is in European populations the basis for around half of all recessively inherited prelingual sensorineural deafness. The aim of our study was to assess the efficacy and utility of the 35delG mutation of the connexin-26 gene analysis for neonates at familial risk, from DNA isolated from Guthrie newborn screening cards. Newborns who had consanguineous parent and/or a familial history of deafness underwent connexin-26 gene analysis from DNA isolated from Guthrie cards and two hearing screening tests (transient evoked otoacoustic emissions, and auditory brainstem recordings). 24 newborns were includes in this pilot study; one of them is homozygous for the 35delG mutation and had abnormal hearing screening tests; all the others newborns had normal connexin gene and at least one normal hearing screening test. Detection on connexin-26 gene mutation is feasible in selected at-risk newborns on one additional blood spot on Guthrie card.

Electromagnetic-field distribution measurements in the soft x-ray range: full characterization of a soft x-ray laser beam

We report direct measurement of the electromagnetic-field spatial distribution in a neonlike Ar capillary discharge-driven soft x-ray laser beam. The wave front was fully characterized in a single shot using a Shack-Hartmann diffractive optics sensor. The wave front was observed to be dependent on the discharge pressure and capillary length, as a result of beam refraction variations in the capillary plasma. The results predict approximately 70% of the laser beam energy can be focused into an area 4 times the size of the diffraction-limited spot, reaching intensities of approximately 4 x 10(13) W/cm(2).

[Tympanostomy tube otorrhea: microbiological epidemiology, pathogen susceptibility to local antibiotics and bactericidal power of the rifamycin-olfloxacin combination]

OBJECTIVE

We studied the microbiological epidemiology of tympanostomy tube otorrhea, rifamycin and ofloxacin sensitivity of pathogens isolated from these otorrheas, and the bactericidal power of the rifamycine-ofloxacin combination.

MATERIAL AND METHODS

A prospective study was conducted in 1997 with cultures of otorrhea aspirates, in vitro study of pathogen resistance to rifamycin and ofloxacin, bacteriocidal study of the rifamycin-ofloxacin combination.

RESULTS

One hundred eight aspirates were obtained from 98 children (mean age 5 years). Ten aspirates were sterile, 32 had more than one pathogen. The more frequent pathogens were Pseudomonas aeruginosa (Pa) (n=35), Staphylococcus aureus (Sa) (n=27), Haemophilus influenae (Hi) (n=12) and Streptococcus pneumoniae (Sp) (n=9). All Hi, all Sp, 86.3% of the Sa (MIC(90) 0.25 mg/l) and none of the Pa were rifamycin sensitive. All Hi, 97.7% of the Pa (MIC(90) 0.5 mg/l), 73,1% of the Sa (MIC(90) 0.24 mg/l) and none of the Sp were ofloxacin sensitive. The rifamycin-ofloxacin combination led to a 4 log CFU/ml decrease in 6 hours for Sp, and in 24 hours for Pa, Hi and Sa.

CONCLUSION

The rifamycin-ofloxacin combination is bactericidal for bacteria causing tympanostomy tube otorrhea. Otic drops with this combination should be considered as the first line treatment for such otorrhea.

[Acute external mastoiditis in children: report of a series of 48 cases]

DESIGN

To determine the impact of the emergence of penicillin-resistant strains of pneumococci on the frequency of acute mastoiditis in children, and to assess the importance of laboratory and imaging studies in the treatment of acute mastoiditis.

METHOD

Retrospective review of the medical records of children with postauricular swelling and otoscopic signs of acute otitis media from January 1993 through December 2000.

RESULTS

Forty-eight children aged three months to 14 years (median 17 months) were identified. The number of cases was almost the same from one year to another. All children had bacteriological examinations. The mastoid pus and the otorrhea was sterile in 22 cases. The most frequent pathogen was Streptococcus pneumoniae (17 cases), which was resistant to penicillin in 71% of cases. The initial body temperature, the number of polymorphonuclears and the CRP were not different between the group of 18 children with periostitis, which required medical treatment alone, and the group of 30 children who had a mastoid abscess which required surgery. The difference between periostitis and mastoid abscess was seen on clinical examination and CTscan.

Anhydrous lead(II) heptanoate

The title compound, catena-poly[[(heptanoato-O,O')lead(II)]-micro-heptanoato-O,O':O:O'], [Pb(C(7)H(13)O(2))(2)], is a metallic soap which can be used as a corrosion inhibitor since it forms a passive film at the Pb surface. Its structure is characterized by two-dimensional layers parallel to the bc plane. The layers are packed through van der Waals interactions along the a direction and form blocks parallel to (001). The 6s(2) lone pair of electrons on Pb(II) is stereochemically active in this compound, which leads to a hemidirected octahedral geometry for the O-environment around the Pb atoms.

Congenital nasal pyriform aperture stenosis: diagnosis and management of 20 cases

The objective of this study was to review the characteristics of congenital nasal pyriform aperture stenosis (CNPAS) in a series of 20 children seen between 1993 and 1996. The diagnosis was made by physical examination and computed tomography scan. A single central maxillary incisor was detected in 12 cases (60%). Three children had morphological abnormalities of the pituitary gland shown on magnetic resonance imaging. One child had an antidiuretic hormone deficiency, and another child had a growth hormone deficiency. Two children had craniosynostoses, 1 of which was Apert's syndrome. All patients underwent operation by a sublabial approach, and 1 was referred for a columellar necrosis after nasal stenting. After surgery, all patients showed improvement, and the nasal stenting was usually removed 1 week after surgery. Follow-up revealed normal breathing. In conclusion, CNPAS was previously considered to be an unusual cause of nasal obstruction in neonates and infants. The number of cases treated recently in our department suggests that this newly recognized entity is more common than expected.

[Single-tooth impressions using metal-resin matrixes]

The metallic-resinous frame impression technique is based on the impression of single abutments encompassed in a global one, with or without transfert copings. For single tooth impression, this technique is the easiest and the most practical alternative to the one using thermoplastic paste. The aim of this article is to describe, step-by-step, the impression taking procedures using the metallic-resinous frame technique.

[Evaluation of the psychometric properties of the Spanish version of 5 questionnaires for the evaluation of post-traumatic stress syndrome]

AIM

To determine the psychometric properties of the Spanish versions of the following scales for assessing PTSD patients: TQ, CAPS-DX, DTS, TOP-8, and DGRP.

METHODS

Data from 63 PTSD patients and 23 healthy subjects were analysed. Internal consistency and test-retest reliability (after 15 days) were calculated. Convergent validity was analysed by correlating subjects' scores with the number of symptoms (DSM-IV) and scores on the CGI scale. Discriminative capability was analysed by comparing TQ, CAPS-DX, DTS, TOP-8, and DGRP patients' scores with scores from healthy subjects, and between patients' subgroups according to the presence or absence of psychiatric comorbidity and to the degree of severity as determined by the CGI-S.

RESULTS

CAPS-DX, DTS, TOP-8, and DGRP showed an adequate internal consistency (Cronbach alpha: 0.74-0.91) and all of them obtained ICC between 0.77 and 0.93. The five questionnaires were able to discriminate between patients and healty subjects, and between the patients' subgroups.

CONCLUSIONS

The Spanish versions of the TQ, CAPS-DX, DTS, TOP-8, and DGRP have shown adequate reliability and validity for assessing PTSD patients in daily clinical practice. CAPS-DX seems to be more adequate a diagnostic and DTS a severity rating scale.

[Direct foreign body footplate trauma: 3 cases]

3 cases of direct foreign body footplate trauma are described in children. A surgical exploration was decided on history, cochleovestibular signs and/or CT abnormalities. Hearing improved in all cases after surgery.

MR imaging features of acute bilateral renal cortical necrosis

Bilateral renal cortical necrosis (BRCN) is an uncommon cause of acute renal failure. Kidney biopsy, arteriography, and contrast-enhanced computed tomography (CT) are usually used to diagnose BRCN. However, these methods can have potentially serious side effects. We report two cases in which magnetic resonance imaging (MRI) evidenced characteristic features of BRCN, which were confirmed by histological findings and arteriography and correlated with clinical evolution. In the first case report, the diagnosis of a massive and complete cortical necrosis variety was suggested on MRI that showed a thin rim of low signal intensity along border of kidneys. It was confirmed on kidney biopsy, and the renal function did not recover. The second case is an incomplete form with cortical patchy areas of low signal intensity. In these two patients, MRI helped to establish an early diagnosis of BRCN with characteristic representative findings, without the potential nephrotoxic effects of iodinated contrast that has to be used in CT and arteriography. Kidney biopsy, besides the risks of complications, provides only a parceled analysis of the renal tissue and therefore does not allow any conclusion as to the extension of cortical necrosis. MRI may be of great help for the diagnosis and follow-up of acute renal cortical necrosis.

Induction of necrosis in human neutrophils by Shigella flexneri requires type III secretion, IpaB and IpaC invasins, and actin polymerization

Infection by Shigella flexneri is characterized by infiltration of neutrophils in the intestinal mucosa and by a strong inflammatory reaction. Although neutrophils are constitutively programmed to die by apoptosis, we show that isolated human neutrophils undergo necrosis 2 h after infection with virulent S. flexneri strain M90T but not with the virulence plasmid-cured strain BS176. This was demonstrated by the release of azurophil granule proteins concomitant with the release of lactate dehydrogenase (LDH), disruption of the plasma membrane, and absence of DNA fragmentation. Mutants with the mxiD1 gene, coding for an essential component of the secretion type III machinery, or the genes coding for IpaB or IpaC invasins deleted were not cytotoxic. Neutrophil necrosis occurred independently of the bacterial ability to leave phagosomes, and it involved actin polymerization, as the addition of cytochalasin D after phagocytosis of Shigella inhibited the release of LDH. In conclusion, Shigella kills neutrophils by necrosis, a process characterized by the release of tissue-injurious granular proteins. This probably contributes to disruption of the epithelial barrier, leading to the dysentery observed in shigellosis and allowing Shigella to enter its host cells.

[What is the role of tonsillectomy in children?]

Tonsillectomy is mandatory in the case of chronic airway obstruction associated with tonsillar hypertrophy and in the case of a unilateral enlarged tonsil which may be malignant. Tonsillectomy may be indicated in recurrent tonsillitis. More rarely, tonsillectomy is performed in children for tonsil bleeding or chronic tonsillitis. Allergy and bleeding disorders are not a contraindication for tonsillectomy.