[High energy proton therapy for extraocular tumors, neurotrophic keratitis and functional consequence: A series of 3 cases]

INTRODUCTION

High energy proton therapy (HEP) is a form of radiation therapy using protons for extraocular tumors. Its ballistic properties are theoretically advantageous, but the real impact on the surrounding ocular tissues during cerebral and ENT irradiation is poorly documented. We describe three consecutive patients with corneal damage following such irradiation.

MATERIALS/METHODS

Post-proton therapy neurotrophic keratitis (NK) is defined as corneal hypo/anesthesia responsible for an alteration of corneal trophicity and graded according to the Mackie classification, in terms of a prospective ophthalmological follow-up protocol for all patients with extraocular tumors treated with HEP.

RESULTS

Among 193 patients treated with HEP between 2018 and 2021 for extraocular tumors, three patients developed severe neurotrophic keratitis, i.e. 1.6% of treated patients. According to the Mackie classification, the three patients showed grade 3 NK less than one year after the conclusion of their HEP. These three patients underwent amniotic membrane grafting. They were placed on autologous serum eye drops. Two of the three patients had to be eviscerated. The dose to the cornea was greater than 50 Gray (Gy)_Relative biological effectiveness (RBE) in the three cases.

DISCUSSION

The diagnosis and etiological origin of neurotrophic keratitis are often difficult to establish. In these cases, the imputability of radiation therapy, proton therapy in our cases, in the development of neurotrophic keratitis was plausible based on the dosimetry of the patients, all of whom had anterior tumors with a poor prognosis requiring high tumoricidal doses.

CONCLUSION

Further studies to establish the impact of proton therapy on corneal sensitivity are necessary. However, this feedback and the multidisciplinary management of tumors can help to limit the risk of some complications of radiation therapy. Early diagnosis allows for appropriate management and could possibly minimize the anatomical and functional ocular complications of neurotrophic keratitis.

[Acute idiopathic eosinophilic pneumonia in a teenager]

Acute idiopathic eosinophilic pneumonia is a very rare cause of interstitial lung disease in children. Pathophysiological mechanisms and etiology remain poorly understood. It manifests as a febrile dyspnea, progressively worsening. Chest X-ray, performed as first-line, shows bilateral infiltrates. The chest CT confirms a diffuse infiltrative pneumopathy and the bronchoalveolar lavage demonstrates the presence of alveolar hypereosinophilia. The exclusion of other causes of alveolar eosinophilia confirms the diagnosis. A ventilatory support is very often necessary. Systemic corticosteroids provides a spectacular clinical improvement, without recurrence.

[Acute disseminated encephalomyelitis: a pediatric case report]

Acute disseminated encephalomyelitis (ADEM) is a disease of the central nervous system (CNS) mainly affecting children. It usually occurs within 2 days to 4 weeks following a triggering factor such a viral infection or an immunization. Clinical presentation is characterized by an acute encephalopathy and by multifocal neurologic abnormalities. In the absence of specific biologic marker, the diagnosis of ADEM is based on clinical, biological and radiological data including cerebrospinal fluid (CSF) analysis and magnetic resonance imaging (MRI). Brain MRI typically shows multifocal lesions predominantly involving the white matter. Treatment is based on high doses of steroids. Intravenous immunoglobulins or plasmapheresis are sometimes required. The prognosis is usually favorable but neurological sequellae can occur.

Everolimus plus exemestane for hormone-receptor-positive, human epidermal growth factor receptor-2-negative advanced breast cancer: overall survival results from BOLERO-2†

BACKGROUND

The BOLERO-2 study previously demonstrated that adding everolimus (EVE) to exemestane (EXE) significantly improved progression-free survival (PFS) by more than twofold in patients with hormone-receptor-positive (HR(+)), HER2-negative advanced breast cancer that recurred or progressed during/after treatment with nonsteroidal aromatase inhibitors (NSAIs). The overall survival (OS) analysis is presented here.

PATIENTS AND METHODS

BOLERO-2 is a phase III, double-blind, randomized international trial comparing EVE 10 mg/day plus EXE 25 mg/day versus placebo (PBO) + EXE 25 mg/day in postmenopausal women with HR(+) advanced breast cancer with prior exposure to NSAIs. The primary end point was PFS by local investigator assessment; OS was a key secondary end point.

RESULTS

At the time of data cutoff (3 October 2013), 410 deaths had occurred and 13 patients remained on treatment. Median OS in patients receiving EVE + EXE was 31.0 months [95% confidence interval (CI) 28.0-34.6 months] compared with 26.6 months (95% CI 22.6-33.1 months) in patients receiving PBO + EXE (hazard ratio = 0.89; 95% CI 0.73-1.10; log-rank P = 0.14). Poststudy treatments were received by 84% of patients in the EVE + EXE arm versus 90% of patients in the PBO + EXE arm. Types of poststudy therapies were balanced across arms, except for chemotherapy (53% EVE + EXE versus 63% PBO + EXE). No new safety concerns were identified.

CONCLUSIONS

In BOLERO-2, adding EVE to EXE did not confer a statistically significant improvement in the secondary end point OS despite producing a clinically meaningful and statistically significant improvement in the primary end point, PFS (4.6-months prolongation in median PFS; P < 0.0001). Ongoing translational research should further refine the benefit of mTOR inhibition and related pathways in this treatment setting.

TRIAL REGISTRATION NUMBER

NCT00863655.

[Anemia in the critically ill child and adult: a narrative review]

Anemia is frequent in the pediatric and adult intensive care unit. Anemia decreases oxygen transport which can be harmful in the critically ill patient; it is independently associated with a poor prognosis. The major prophylactic measure against anemia is the limitation of blood draws: several approaches can be used to limit phlebotomy overdraw without harming the patient. Red blood cell transfusion is the quickest way to increase the hemoglobin level, but it is not without risk. It is therefore important to promote the use of evidence-based transfusion strategies. Iron could be useful in case of iron deficiency, but this condition is difficult to diagnose in the critically ill patient. Erythropoietin is no longer relevant in the intensive care unit in the era of restrictive transfusion practice, at least for its hematological effects. Several questions remain to be addressed in order to improve anemia management in the intensive care unit.

Phase I trial combining temozolomide plus lapatinib for the treatment of brain metastases in patients with HER2-positive metastatic breast cancer: the LAPTEM trial

BACKGROUND

Brain metastases (BMs) pose a clinical challenge in breast cancer (BC). Lapatinib or temozolomide showed activity in BM. Our study assessed the combination of both drugs as treatment for patients with HER2-positive BC and BM.

METHODS

Eighteen patients were enrolled, with sixteen of them having recurrent or progressive BM. Any type of previous therapy was allowed, and disease was assessed by gadolinium (Gd)-enhanced magnetic resonance imaging (MRI). The primary end points were the evaluation of the dose-limiting toxicities (DLTs) and the determination of the maximum-tolerated dose (MTD). The secondary end points included objective response rate, clinical benefit and duration of response.

RESULTS

The lapatinib-temozolomide regimen showed a favorable toxicity profile because the MTD could not be reached. The most common adverse events (AEs) were fatigue, diarrhea and constipation. Disease stabilization was achieved in 10 out of 15 assessable patients. The estimated median survival time for the 16 patients with BM reached 10.94 months (95% CI: 1.09-20.79), whereas the median progression-free survival time was 2.60 months [95% confidence interval (CI): 1.82-3.37].

CONCLUSIONS

The lapatinib-temozolomide combination is well tolerated. Preliminary evidence of clinical activity was observed in a heavily pretreated population, as indicated by the volumetric reductions occurring in brain lesions.

Autoimmune haemolytic anaemia in a patient treated with capecitabine

A 61-year-old female, followed-up for a metastatic breast cancer, was admitted in our institution with conjunctival icterus, asthenia and abdominal crampoid pain. The patient was included in a clinical trial comparing the efficiency of capecitabine monotherapy versus capecitabine conjugated with a new biological agent in a randomised and double blind trial. The patient was in the capecitabine alone arm. Biological tests performed upon admission suggested the diagnosis of haemolytic anaemia. Moreover, the direct Coombs test result was twice positive indicating autoimmune haemolytic anaemia. Capecitabine has been reported to cause haemolysis either alone or combined with lapatinib, each time with a mechanism other than immunological. In this clinical case, capecitabine is the most likely factor causing an autoimmune haemolytic anaemia.

Oxaliplatin and 5-fluorouracil in heavily pretreated patients with ovarian carcinoma: A well tolerated and efficient treatment

16028

Background: Recurrent ovarian cancer is an incurable disease. The prognosis of patients with platinum refractory disease is dismal. We present data from heavily pretreated patients with recurrent ovarian cancer to whom the Folfox regimen was administered. Methods: Patients with recurrent, resistant or refractory, pretreated ovarian carcinoma were eligible for this compassionate use program of oxaliplatin (85 mg/m2 in 2 hours) and leucovorin (200 mg/m2 in 1 hour) on day 1, followed by a continuous infusion of 5FU (2,600 mg/m2 in 48 hours), every 2 weeks. The objectives of the study were primarily to assess response rate and secondarily to evaluate the safety profile. Results: Fourteen patients were treated. Median age: 56 years (49–70). Performance status: 0 (n=4) and 1 (n=10). Median number of previous chemotherapy regimens: 5 (3–10) and previous platinum-based regimens: 2 (1–3). Median chemotherapy-free interval: 9.5 weeks (1–39). Median administered cycles of Folfox/patient: 8 (2–11 cycles). Responses according to RECIST criteria: 2 CR (14.5%), 2 PR (14.5%), 4 SD (29%) and 6 PD (43%). Responses according to CA125 Rustin's criteria: 4 CR (29%), 2 PR (14.5%), 5 SD (35.5%) and 3 PD (21%). Grade 1/2 and 3 peripheral neuropathy: 10 (71%) and 2 (14.5%), respectively. There were no grade 4 adverse events or deaths due to the treatment. Conclusions: Folfox is a valuable option for heavily pre-treated patients with ovarian cancer, with an overall response rate of 29% (95% CI 15.2% to 41.8%), disease stabilization in an additional 29%, and a manageable toxicity profile. These results support the use of Folfox as salvage treatment for patients with ovarian carcinoma.

No significant financial relationships to disclose.

National survey of molecular epidemiology of Staphylococcus aureus colonization in Belgian cystic fibrosis patients

OBJECTIVES

Epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) is poorly defined in cystic fibrosis (CF) patients, and S. aureus detection may be hampered by the presence of small colony variants (SCVs). We conducted a multicentre survey to determine the prevalence of S. aureus and MRSA colonization in Belgian CF patients and characterize the phenotype and clonal distribution of their staphylococcal strains.

METHODS

S. aureus isolated from CF patients attending nine CF centres were collected. Oxacillin resistance was detected by oxacillin agar screen and mecA PCR. Antibiotic susceptibility was tested by microdilution. MRSA strains were genotyped by PFGE and SCCmec typing and compared with hospital-associated MRSA strains.

RESULTS

Laboratories used a diversity of sputum culture procedures, many of which appeared substandard. S. aureus was isolated from 275/627 (44%) CF patients (20% to 72% by centre). The prevalence of SCV colonization was 4%, but SCVs were almost exclusively recovered from patients in two centres performing an SCV search. Phenotypically, 14% of S. aureus isolates were oxacillin-resistant: 79% carried mecA and 19% were SCVs lacking mecA. The mean prevalence of 'true' MRSA colonization was 5% (0% to 17% by centre). By PFGE typing, 67% of CF-associated MRSA were related to five epidemic clones widespread in Belgian hospitals.

CONCLUSIONS

This first survey of S. aureus colonization in the Belgian CF population indicated a diversity in local prevalence rates and in proportion of oxacillin-resistant and SCV phenotypes, probably related to variation in bacteriological methods. These findings underscore the need for standard S. aureus detection methods and MRSA control policies in Belgian CF centres.

Appendicitis in pregnancy: a case report and a review of the current literature

Acute appendicitis is the most common surgical problem in pregnancy. Antibiotic treatment does not always improve the outcome and emergency intervention is required. We present a case of appendicitis complicated by a plastron formation occurring during pregnancy and the outcome.

[Arterial duplex and aortic valve stenosis: sensitivity and specificity of findings]

Purposes. In this prospective study, we sought to determine the sensitivity and the specificity of arterial Doppler findings of valvular aortic stenosis (VAS).

PATIENTS AND METHODS

20 control subjects and 20 patients with various degrees of VAS underwent Doppler ultrasound of the carotids, abdominal aorta, renal arteries and limb arteries. We analyzed and compared the shape of the spectral profiles, peak systolic velocity (PSV), systolic upstroke time (SUT) and systolic upstroke index (SUI) of every tracing. The protodiastolic notch (PDN) of the common femoral arteries were recorded too.

RESULTS

VAS hardly modifies the overall shape of the Doppler spectrums of the aorta or limb arteries but it implies a biphasic deformation or a doubling of the systolic peak of the neck vessels. We also encountered biphasic profiles in renal arteries of patients with tight VAS. The PSV, SUI and depth of the PDN tend to diminish in cases of VAS but the variations are inconstant and rarely proportional to the severity of the narrowing. The increase of the SUT, on the contrary, is linearly correlated to the severity of the stenosis in every arterial system: SUTs in the common carotid artery, internal carotid artery or brachial artery that are shorter than or equal to 70 milliseconds (msec) are the obvious marks of the absence of VAS. It was not possible to differentiate between the intermediate stenoses (aortic valve area between 0.8 and 2 square centimeters) whereas critical aortic stenoses, whose area is less than or equal to 0.7 square centimeter, can be detected by the presence of at least two of the four following criteria of SUT: equal to or above 180 msec for the common carotid, 200 msec for the internal carotid, 130 msec for the aorta and 110 msec for the common femoral artery.

CONCLUSION

During routine arterial Doppler ultrasound, a precise analysis of the spectrums and some SUT measurements allow the assessment of the aortic valve.

Bax and Bid, two proapoptotic Bcl-2 family members, inhibit homologous recombination, independently of apoptosis regulation

In order to analyse the relationships between regulation of apoptosis and homologous recombination (HR), we overexpressed proapoptotic Bax or only-BH3 Bid proteins or antiapoptotic Bcl-2 or Bcl-XL, in hamster CHO cells or in SV40-transformed human fibroblasts. We measured HR induced by gamma-rays, UVC or a specific double-strand cleavage targeted in the recombination substrate by the meganuclease I-SceI. We show here that the induction of both recombinant cells and recombinant colonies was impaired when expressing Bcl-2 family members, in hamster as well as in human cells. Moreover, the pro- as well as antiapoptotic Bcl-2 family members inhibited HR, independently of degradation of the RAD51 recombination protein and of their impact on apoptosis. These data reveal a mechanism of HR downregulation by potentially proapoptotic proteins, distinct from and parallel to degradation of recombination proteins, a situation that should also optimize the efficiency of programmed cell death.

Adjuvant chemotherapy in 2005: Standards and beyond

The 2003 St. Gallen consensus panel divided the many available adjuvant chemotherapy (CT) regimens into those with "standard efficacy" (ACx4, CMFx6) and those with "superior efficacy" (FA(E)Cx6, CA(E)Fx6, A(E)-->CMF, TACx6, ACx4--> paclitaxel (P)x4 or docetaxel (D)x4) but also greater complexity, toxicity and cost. This paper will summarize the latest information on long-term side effects of the "superior" regimens and 5-year benefits reported in taxane trials, including those of a "new" sequential regimen, FECx3--> docetaxelx3. Rapidly expanding evidence of marked heterogeneity in the magnitude of CT benefits according to the tumour oestrogen receptor (ER) status, a claim made for many years by IBCSG investigators, will be reviewed; it will lead to the conclusion that a revolution needs to take place in the way oncologists think about the CT added value and design adjuvant clinical trials. The conclusions proposed to the 2005 St. Gallen consensus panel are that: adequately dosed anthracycline-based CT regimens remain an acceptable standard for many women; a lower threshold for using taxanes in sequence or combination with anthracyclines (A) is justified in the presence of an ER-negative or low-ER tumour status, other aggressive biologic features (such as HER-2 overexpression), fear about A-induced cardiotoxicity; no recommendation can yet be made as far as the optimal taxane-A regimen, the best taxane or the best taxane schedule.

Functional and structural alterations of epithelial barrier properties of rat ileum following X-irradiation

Irradiation of the digestive system leads to alterations of the small intestine. We have characterized the disruption of the barrier integrity in rat ileum from 1 to 14 days following irradiation ranging from 6 to 12 Gy. The intestinal permeability to 14C-mannitol and 3H-dextran 70 000 was measured in vitro in Ussing chambers. In parallel to these functional studies, immunohistochemical analyses of junctional proteins (ZO-1 and beta-catenin) of ileal epithelium were performed by confocal microscopy. Irradiation with 10 Gy induced a marked decrease in epithelial tissue resistance at three days and a fivefold increase in mannitol permeability, without modifications of dextran permeability. A disorganization of the localization for ZO-1 and beta-catenin was also observed. At 7 days after irradiation, we observed a recovery of the organization of junctional proteins in parallel to a return of intestinal permeability to control value. In addition to these time-dependent effects, a gradual effect on epithelial integrity of the radiation doses was observed 3 days after irradiation. This study shows a disruption of the integrity of the intestinal barrier in rat ileum following abdominal X-irradiation, depending on the time postirradiation and on the delivered dose. The loss of barrier integrity was characterized by a disorganization of proteins of tight and adherent junctions, leading to increased intestinal permeability to mannitol.

[Amaurosis fugax of cardiac origin]

We present the case of a 49 year old woman who was admitted to the emergency department for dyspnoea, transient amaurosis and limbs oedema. During hospitalisation a full workup revealed multisystemic thrombosis and dilated cardiomyopathy in relation with viral myocarditis due to Coxackie B infection. Diagnosis and treatment will be discussed in light of the litterature.

Compact sources as the origin of the soft γ-ray emission of the Milky Way

The Milky Way is known to be an abundant source of gamma-ray photons, now determined to be mainly diffuse in nature and resulting from interstellar processes. In the soft gamma-ray domain, point sources are expected to dominate, but the lack of sensitive high-resolution observations did not allow for a clear estimate of the contribution from such sources. Even the best imaging experiment revealed only a few point sources, accounting for about 50% of the total Galactic flux. Theoretical studies were unable to explain the remaining intense diffuse emission. Investigating the origin of the soft gamma-rays is therefore necessary to determine the dominant particle acceleration processes and to gain insights into the physical and chemical equilibrium of the interstellar medium. Here we report observations in the soft gamma-ray domain that reveal numerous compact sources. We show that these sources account for the entirety of the Milky Way's emission in soft gamma-rays, leaving at most a minor role for diffuse processes.

Influence of peroperative opioid on postoperative pain after major abdominal surgery: sufentanil TCI versus remifentanil TCI. A randomized, controlled study

BACKGROUND

Sufentanil and remifentanil are characterized by two different pharmacokinetic profiles. The aim of this study was to compare the effects of sufentanil and remifentanil administered using target-controlled infusion (TCI) on recovery and postoperative analgesia after major abdominal surgery.

METHODS

Thirty adult patients scheduled for open colorectal surgery were included in a prospective, randomized study. Sufentanil TCI (sufentanil group) or remifentanil TCI (remifentanil group) was administered during surgery. In the remifentanil group, 30 min before the anticipated end of surgery, morphine 0.15 mg x kg(-1) was administered i.v. In the sufentanil group, an effect-site concentration of 0.25 ng x ml(-1) was targeted at extubation. In both groups, postoperative pain was controlled by titration of i.v. morphine and then patient-controlled analgesia with morphine.

RESULTS

The extubation time was similar in the two groups (mean (SD) 13 (6) and 14 (6) min in the sufentanil and remifentanil groups respectively). Visual analogue scale scores were significantly greater during the first 2 h after tracheal extubation in the remifentanil group than in the sufentanil group. The time to first analgesic request in the postanaesthesia care unit was significantly longer in the sufentanil group than in the remifentanil group (55 (64) (range 2-240) vs 11 (7) (1-29) min; P<0.001). The cumulative morphine dose for titration was significantly greater in the remifentanil group (P<0.01). The cumulative morphine dose used during titration and patient-controlled analgesia was significantly greater in the remifentanil group 4, 12 and 24 h after extubation (P<0.05).

CONCLUSION

TCI sufentanil (0.25 ng ml(-1) effect-site concentration at extubation) is more effective than the intraoperative combination of remifentanil TCI infusion with morphine bolus (0.15 mg x kg(-1)) for postoperative pain relief after major abdominal surgery and does not compromise extubation and recovery.

Potential role of the membrane in the development of intestinal cellular damage after whole-body gamma irradiation of the rat

Our study emphasizes the effect of gamma irradiation on intestinal cell membrane fluidity and addresses the potential relationships existing between radiation-induced lipoperoxidation, membrane fluidity, and changes in membrane protein activities. Male Wistar rats were exposed to an 8-Gy total body irradiation (60Co source) and studied 1, 4, and 7 days after irradiation (D1, D4, and D7). Membrane enzyme activities and fluorescence anisotropy were determined on small intestinal crude membrane preparations. The supernatants of membrane preparations as well as plasma were used for malonedialdehyde (MDA) quantification. The effect of carbamylcholine on electrical parameters was estimated on distal ileum placed in Ussing chambers. We observed a decrease in fluorescence anisotropy for at least 7 days, an increase in membrane production of MDA at D4, a decrease in membrane enzyme activities at D4, but an amplification of carbamylcholine-induced increase in short-circuit current at D4 and D7. Furthermore, correlations were observed between the 1,6-diphenyl-1,3,5-hexatriene anisotropy coefficient and sucrase activity and between MDA levels and leucine aminopeptidase activity. Thus, total body irradiation induces changes in intestinal membrane fluidity and an increase in lipoperoxidation. These modifications may have an impact on the activity of membrane proteins involved in intestinal function.

Alterations of the VIP-stimulated cAMP pathway in rat distal colon after abdominal irradiation

Ionizing radiation induces hyporesponsiveness of rat colonic mucosa to vasoactive intestinal peptide (VIP). Possible mechanisms responsible for this hyporesponsiveness of the cAMP communication pathway in rat colon were investigated. VIP- and forskolin-stimulated short-circuit current (I(sc)) responses were studied after a 10-Gy abdominal irradiation in Ussing chambers as well as in single, isolated crypts. Adenylyl cyclase (AC) activity and VIP receptor characteristics were determined in mucosal membrane preparations. In addition, alterations in crypt morphology were studied. Impaired secretory responses to VIP and forskolin were observed 4 days after irradiation (decrease of 80%). cAMP analog-stimulated I(sc) responses were unchanged. In isolated crypts, VIP- and forskolin-stimulated cAMP accumulation was markedly reduced by 80 and 50%, respectively. VIP-stimulated AC activity and VIP receptor number were decreased in membrane preparations. No major change of cellularity was associated with these functional alterations. In conclusion, the decreased secretory responses to VIP of rat colon are associated with reduced cAMP accumulation, decreased AC activity, and diminution of VIP receptor numbers without a marked decrease of crypt cell number.

Quantitation of functional mitral regurgitation during bicycle exercise in patients with heart failure

OBJECTIVES

We sought to examine the feasibility and reliability of quantifying mitral regurgitation (MR) during exercise by Doppler echocardiography in patients with heart failure and to assess the relationship between dynamic MR and systolic pulmonary artery pressure changes.

BACKGROUND

The severity of MR can be quantified by using several echocardiographic methods. Quantitation of MR during dynamic exercise has not yet been performed.

METHODS

Symptom-limited, semi-supine two-dimensional and Doppler echocardiograms during bicycle exercise were obtained in 27 consecutive patients with heart failure and functional MR. Regurgitant volume was measured at rest and during exercise by the proximal isovelocity surface area (PISA) method and by quantitative Doppler echocardiography. Exercise-induced changes in regurgitant volume were compared with changes in the regurgitant jet area to left atrial area ratio, vena contracta width and trans-tricuspid pressure gradient.

RESULTS

The regurgitant volume measured by the PISA method increased from 21 +/- 12 ml (range 5 to 55) at rest to 39 +/- 23 ml (range 8 to 85) during exercise (p < 0.0001). The difference between two observers was low for both rest (2.0 +/- 2.7 ml) and exercise measurements (3.5 +/- 6.2 ml). The regurgitant volume measured by quantitative Doppler echocardiography increased from 29 +/- 13 to 49 +/- 24 ml (p = 0.0001). Excellent correlation between the two methods was obtained with exercise (r = 0.92). Exercise-induced changes in regurgitant volume, as measured by the PISA method, correlated well with regurgitant volume changes measured by quantitative Doppler echocardiography (r = 0.88), changes in vena contracta width (r = 0.82) and changes in trans-tricuspid pressure gradient (r = 0.73), but not with changes in regurgitant jet area to left atrial area ratio (r = 0.29). Seventeen patients stopped exercise because of fatigue and 10 because of dyspnea. These 10 patients exhibited greater increases in regurgitant volume (34 +/- 6 vs. 11 +/- 8 ml), corresponding to a significant elevation of the trans-tricuspid gradient (48 +/- 14 vs. 20 +/- 14 mm Hg).

CONCLUSIONS

Quantitation of functional MR during exercise is feasible in patients with heart failure. There is a good correlation between regurgitant volume measured during exercise by the PISA method and that obtained by quantitative Doppler echocardiography, suggesting that the technique is reliable. An increase in mitral regurgitant volume during dynamic exercise correlates well with elevation of systolic pulmonary artery pressure.

[Not Available]

Les crises démographiques, bien qu'accidents conjoncturels par définition, apparaissent, par leur gravité et leur fréquence, comme un des traits structurels les plus caractéristiques de la démographie de type ancien. Il suffit d'examiner n'importe quelle « courbe paroissiale longue » aux XVIIe et XVIIIe siècles pour être immédiatement frappé par les « clochers » de mortalité qui, à intervalles plus ou moins réguliers, traduisent une hausse brutale du nombre des décès. Toutefois, cette hausse ne caractérise pas à elle seule la crise démographique et il serait donc erroné de désigner celle-ci sous le terme trop restrictif de crise de mortalité. En effet, à l'augmentation des décès s'ajoutent, dans certains cas, une baisse corrélative des conceptions et des mariages et une recrudescence des abandons d'enfants et des phénomènes d'errance. Il est vrai cependant que la crise démographique, si complexes qu'en soient les effets, est d'abord, et souvent uniquement, une « mortalité » pour reprendre le terme employé par les contemporains. C'est pourquoi le premier problème qui se pose à l'historien est de définir, à partir du chiffre des décès, l'existence même d'une crise et son éventuelle intensité.

[Pneumomediastinum in children]

Pneumomediastinum in children is diagnosed in two circumstances: cervical subcutaneous emphysema or radiological findings. The predominant symptoms are dyspnoea, stabbing chest pain, sore throat and dysphagia. Traumatic injuries and pulmonary diseases such as asthma are the most common causes of pneumomediastinum. It may rarely result from iatrogenic manoeuvres or acidocetosis. Spontaneous mediastinal emphysema is seldom reported in children. Chest X-ray films are essential investigations. The treatment is directed towards the underlying cause, with conservative management being sufficient in most cases. However, the risk of surveying of pneumothorax or tension pneumomediastinum justifies close clinical follow-up in a specialised care unit. The onset of these pathologies necessitates a more aggressive therapy by aspiration through percutaneous catheter placed in the mediastinum.

Radiation induced cytochrome c release causes loss of rat colonic fluid absorption by damage to crypts and pericryptal myofibroblasts

BACKGROUND

Therapeutic or accidental exposure to radiation commonly causes gastrointestinal disturbances, including diarrhoea. Rats subjected to whole body ionising radiation at a dose of 8 Gy lose their capacity to absorb fluid via the descending colon after four days. After seven days, fluid absorption recovers to control levels.

AIMS

To investigate the effect of ionising radiation on colonic permeability together with its effect on mitochondria dependent apoptotic signals and intercellular adhesion molecules.

METHODS

Rats were irradiated with doses of 0-12 Gy. Colonic permeability was measured by accumulation of fluorescein isothiocyanate (FITC) dextran in crypt lumens. Changes in levels of cytochrome c, caspase 3, E and OB cadherin, beta-catenin smooth muscle actin, and collagen IV were assessed using immunocytochemistry with confocal microscopy.

RESULTS

Cytosolic cytochrome c increased after 8 Gy (t(1/2) 1.4 (0.6) hours) and peaked at approximately six hours. Caspase 3 increased more slowly, particularly in crypt epithelial cells (t(1/2) 57 (14.5) hours). Pericryptal myofibroblasts disintegrated within 24 hours as was evident from loss of OB cadherin and smooth muscle actin. This coincided with increased crypt permeability to dextran. Intercellular adhesion between crypt luminal cells was not lost until day 4 when both beta-catenin and E-cadherin were minimal. The half maximal dose-response for these effects was in the range 2-4 Gy. Recovery of colonic transport was concurrent with recovery of pericryptal smooth muscle actin and OB cadherin. The pan caspase inhibitor Z-Val-Ala-Asp.fluoromethylketone (1 mg/kg per day) had a small effect in conserving the pericryptal sheath myofibroblasts and sheath permeability but had no systemic therapeutic effects.

CONCLUSIONS

These data suggest that radiation damage to the colon may be initiated by mitochondrial events. Loss of crypt fluid absorption and increased permeability coincided with decreased intercellular adhesion between crypt epithelial cells and loss of pericryptal sheath barrier function.

Modified absorptive and secretory processes in the rat distal colon after neutron irradiation: in vivo and in vitro studies

Impaired fluid and electrolyte transport in the intestine is a well-recognized characteristic of radiation-induced pathologies in the gastrointestinal tract. The aim of this study was to investigate the responsiveness of the epithelium of the colon of the rat to electrical and pharmacological (serotonin, carbachol) stimulation concomitantly with in vivo assessment of the absorptive capacity of the colon at 1, 3, 5 and 7 days after 3.8 Gy whole-body exposure to neutrons. The responsiveness of rat colon in vitro to electrical stimulation and the number of mast cells were measured to examine the role of neuroimmune networks in radiation-induced dysfunction. Animals showed an impaired capacity of the colon to absorb water and sodium from 3 to 5 days after irradiation together with decreased responsiveness to electrical and pharmacological stimulation. The time course of decreased responsiveness to neural stimulation was similar to that of impaired absorption observed in vivo, but it was not correlated with variations in mast cell numbers. Histological (mast cells) and biochemical analyses (myeloperoxidase and NO synthase activities) did not find evidence of a marked infiltration and/or activation of inflammatory cells. Thus the impaired absorptive capacity of the colon observed after irradiation occurs concomitantly with decreased neural influence, and is possibly related to reduced epithelial functional capacity but not to decreased mast cell numbers.

Neurological and physical maturation in normal growth singletons from 37 to 41 weeks' gestation

An evaluator blinded to gestational age (GA) assessed a cohort of 397 singletons born at between 37 and 41 week's gestation, by looking at 11 criteria exploring neurological maturity and 12 criteria exploring physical maturity. The analysis of correlation coefficients shows various degrees of association between GA and each of the criteria examined. A highly significant correlation (p < 0.001) was found for 4 neurological criteria defining passive tone in limbs and sucking reflex. The activity of flexor muscles of the neck and crossed extension reflex were also associated with maturity but weakly (p < 0.01). A highly significant correlation (p < 0.001) was found for 8 of the physical criteria, skin colour and texture, lanugo, ear firmness, genitalia, breast size, nipple formation and plantar skin creases. Oedema, skull firmness and ear form were also associated but weakly. With multivariate analysis combining the neurological and physical criteria, predictive values ranked in the following order: 1) plantar skin, 2) breast size, 3) sucking reflex, 4) scarf sign, 5) skin colour, 6) genitalia, 7) popliteal angle, 8) return to flexion of forearms, 9) dorsiflexion angle. In conclusion, a score based on physical and neurological criteria is associated with duration of pregnancy (r2 = 0.32) between 37 and 41 weeks' gestation. Such an instrument allows us to study fetal maturity as a variable independent of GA, and therefore makes it possible to identify various influences that may modify maturational rate during the last weeks of pregnancy.

Ionizing radiation stimulates muscarinic regulation of rat intestinal mucosal function

The aim of this study was to determine whether ionizing radiation modifies muscarinic regulation of intestinal mucosal function. Rats exposed to total body 8-Gy gamma-irradiation or sham irradiated were studied up to 21 days after irradiation. Basal and carbachol-stimulated short-circuit current (Isc) and transepithelial conductance (Gt) of stripped ileum were determined in Ussing chambers. Muscarinic receptor characteristics using the muscarinic antagonist [3H]quinuclidinyl benzilate and three unlabeled antagonists were measured in small intestinal plasma membranes together with two marker enzyme activities (sucrase, Na+-K+-ATPase). Enzyme activities were decreased 4 days after irradiation (day 4). Basal electrical parameters were unchanged. Maximal carbachol-induced changes in Isc and Gt were increased at day 4 (maximal DeltaIsc = 195.8 +/- 14.7 microA/cm2, n = 19, vs. 115.4 +/- 8.2 microA/cm2, n = 63, for control rats) and unchanged at day 7. Dissociation constant was decreased at day 4 (0.73 +/- 0.29 nM, n = 10, vs. 2.14 +/- 0.39 nM, n = 13, for control rats) but unchanged at day 7, without change in binding site number. Thus total body irradiation induces a temporary stimulation of cholinergic regulation of mucosal intestinal function that may result in radiation-induced diarrhea.

An unconscious patient with an electrocardiogram mimicking an acute myocardial infarct

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Exposure to either gamma or a mixed neutron/gamma field irradiation modifies vasoactive intestinal peptide receptor characteristics in membranes isolated from pig jejunum

The effect of acute whole body exposure to ionizing radiation was investigated on intestinal vasoactive intestinal peptide (VIP) receptors and adenylate cyclase activity in membranes isolated from pig jejunum. Pigs under light anaesthesia were exposed to a single dose (6 Gy) of gamma (gamma) or to mixed neutron/gamma field (ratio 1:1; neutron/gamma) irradiation. Seven days after irradiation, plasma-membranes were prepared from post mortem jejunal mucosal scrapings. Marker enzyme activities (sucrase, leucine aminopeptidase (LAP), Na,K-ATPase) were measured in each preparation. The characteristics (KD, Bmax) of VIP receptors were determined using 125I-labelled VIP. In addition VIP-sensitive adenylate cyclase activity was measured. Results showed that enzyme activities were reduced following both gamma (sucrase 67%; LAP 53%; Na/K-ATPase 29%; N = 7) and neutron/gamma (sucrase 53%; LAP 59%; Na/K-ATPase 68%; N = 5) compared with control values (N = 5). VIP receptor affinity was decreased following either type of irradiation (gamma or neutron/gamma P < 0.01) and receptor numbers increased. Both VIP- and forskolin-stimulated adenylate cyclase activities were reduced but the sensitivity of the enzyme remained the same for VIP (EC50 values (nmol dm-3)-control-1.27 +/- 0.35; gamma-2.18 +/- 0.41; neutron/gamma-1.91 +/- 0.28). In conclusion, exposure to either gamma or neutron/gamma irradiation attenuates intestinal enzyme activities and VIP receptor affinity but increases VIP receptor numbers.