The impact of homogeniser speed, dispersing aggregate size and centrifugation on particle size analyses of pork as a measure of myofibrillar fragmentation.

Particle size analysis has been proposed as a measure of myofibrillar fragmentation resulting from post-mortem proteolysis in meat. The aim of this study was to examine the effect of homogenisation speed, dispersing aggregate size and centrifugation on particle size characteristics of pork loin. Particle size characteristics were significantly (P≤0.023) greater for samples aged 2 than 8d for all but the 80 and 90% quantiles. Differentiation with ageing was only achieved when homogenised at 11,000rpm using the smaller dispersing aggregate (9 vs 13mm rotor diameters). Centrifugation had no effect on particle size characteristics. Significant correlations with MFI (r=-0.40 to -0.81, P<0.001) and shear force in meat aged at 3.7°C (r=0.36-0.47; P<0.001) were observed. Weak or inconsistent correlations with shear force suggest adoption of particle size analyses as a method of tenderness classification unlikely. Rather, value lies in the detailed profiles of particle size distributions with meat ageing.

Umami and related components in "chilled" pork for the Japanese market.

The aim of this study was to evaluate umami-related components and their evolution in Canadian pork destined for the Japanese market. Export quality pork loins for Japan were subjectively selected on-line for marbling, colour and firmness; remaining loins were retained for the domestic market. At 48h post-mortem, samples were aged 5d at 4.0°C (fresh) or 13, 28, 43 or 58d at -1.7°C (chilled). Meat qualities differed only in pH (<0.1 pH unit; P<0.05). Generally, free amino acid concentrations increased and nucleotide concentrations decreased with longer ageing periods. The equivalent umami concentration (EUC) was highest in the pork aged 5d at 4.0°C and at 43d -1.7°C (P<0.05) which is estimated as the transportation time for Canadian chilled exports to Japan. A lack of differences in EUC between domestic and export pork and between fresh and 43d chilled ageing demonstrates that Canadian chilled pork in Japan has the EUC of its fresh 5d counterpart.

Ultrasound to diagnose spontaneous intestinal perforation in infants weighing ⩽ 1000 g at birth.

OBJECTIVE: To evaluate the usefulness of abdominal ultrasound in infants with gasless abdomen radiographically suspected to have spontaneous intestinal perforation (SIP). STUDY DESIGN: This was a retrospective analysis of data from our neonatal database including infants with birth weight ⩽ 1000 g with suspicion of SIP, for the period January 2000 to May 2012. RESULT: Four hundred and ninety-six infants weighing ⩽ 1000 g were identified. There were 68 infants with suspicion for SIP, 11 with pneumoperitoneum and 57 with gasless abdomen on X-rays. Ultrasound was performed in 55 of 57 infants with gasless abdomen, 10 with SIP and 45 nonperforated. Echogenic free fluid (EFF) was present in 70% of patients with SIP and 11% of nonperforated patients (P<0.001). When performed within 2 days of surgical diagnosis, EFF had 100% sensitivity and 89% specificity, with 58% positive predictive value and 100% negative predictive value. CONCLUSION: These data suggest that abdominal ultrasound may be useful for the diagnosis of SIP in infants with birth weight ⩽ 1000 g presenting with gasless abdomen.

[Potential advantages a new syringe pump system]. / Avantages potentiels d'un nouveau système de pousse-seringues.

OBJECTIVES: To evaluate what could be the benefit in terms of alarm suppression, of a new syringe pumps system, which allows automatic relay without alarms. PATIENTS AND METHODS: We have prospectively recorded the nature and the mode of relay of all syringe pumps for administration of drugs to patients in two ICU. The perfusion regimen was studied in 61 patients over the complete duration of their stay in two ICU. Alarms were also recorded in one ICU room, over 13 days consecutive. The records were processed off-line with an automatic detection-recognition system in order to assess the origin of each alarm. Accordingly, the amount of alarm corresponding to monitor, ventilator and syringe pumps was computed. RESULTS: We found that syringe pumps, which would provide automatic relays without alarm, would suppress 17% of alarms in ICU and automatize 65% of the relay procedures, which are usually performed often in emergency, on response to the end of perfusion alarm. CONCLUSION: New syringe pumps allow both reduction of alarms in ICU and a better management of nurse workload. Indeed syringe relay can be planned in advance.

Development of noninvasive and quantitative methodologies for the assessment of chronic ulcers and scars in humans.

Chronic ulcers are a significant and common cause of morbidity and mortality worldwide. They disrupt the epidermis and dermis, resulting in a loss of barrier function. Keloids and hypertrophic scars (benign cutaneous tumors) represent an abnormal healing response. These fibroproliferative disorders are characterized by an overabundance of collagen and accumulation of extracellular matrix due to an imbalance between synthesis and degradation, culminating in excessive scarring. The objectives of this study were to evaluate and compare noninvasive biophysical methods for the measurement of outstanding quantitative parameters of scars and chronic ulcers, and to establish correlations between the parameters measured and the results of conventional subjective clinical evaluations. The development of new technologies, based on ultrasonography and laser Doppler, makes possible new dermatological evaluation methods. Fifteen patients (6 females and 9 males) with 15 chronic ulcers (4 diabetic ulcers, 10 venous ulcers and 1 pressure ulcer) and 30 patients (19 females and 11 males) with 30 scars (25 hypertrophic and 5 keloids) were included in this study. Clinical evaluation was performed by a dermatologist, an aesthetic surgeon and an endocrinologist. Biophysical measurements were used to assess local blood flow by laser Doppler flowmetry (Moor DRT4), thickness and echogenicity by high frequency ultrasonography (20 MHz, Dermascan C) and ulcer linear dimensions by image analysis. Our results show that blood flow within the ulcers and scars was higher than within normal skin. Also, skin thickness of chronic ulcers was decreased when compared to normal skin; the thickness of hypertrophic scars, but not of keloids, was increased in comparison to normal skin, and presented the possibility of measuring wound and scar surfaces with precision. In summary, this pilot study established the feasibility of measuring various biophysical parameters and adapted their potential utility to research on wounds.

[Right atrioventricular metastasis of a myxoid liposarcoma. Case report and al review of the literature]. / Métastase auriculo-ventriculaire droite d'un liposarcome myxoïde. A propos d'un cas et revue de la littérature.

Malignant tumours of the heart and pericardium are rare. Secondary tumours are 20 to 40 times more common than primary tumours. The authors report the case of a cardiac metastasis of a myxoid liposarcoma of the inguinal region. Surgical ablation with chemotherapy significantly improved the patient' clinical and haemodynamic status. A review of the literature shows that postoperative survival does not exceed 2 years, but the prognosis is better when chemotherapy is associated with surgery. Transoesophageal echocardiography is an excellent diagnostic imaging method. It provides a better evaluation of the tumour and its location, compared to thoracic CT scan and transthoracic echocardiography.

Hydroxyl radical production in the cortex and striatum in a rat model of focal cerebral ischemia.

BACKGROUND: Increases in hydroxyl radical production have been used as evidence of oxidative stress in cerebral ischemia/ reperfusion. Ischemia can also induce increased dopamine release from the striatum that may contribute to hydroxyl radical formation. We have compared hydroxyl radical production in the cortex and striatum as an index of oxidative stress in a rat model of focal cerebral ischemia with cortical infarction. METHODS: Using a three vessel occlusion model of focal cerebral ischemia combined with bilateral microdialysis, hydroxylation of 4-hydroxybenzoate (4HB) was continuously monitored in both hemispheres in either the lateral striatum or frontoparietal cortex. The ischemia protocol consisted of one hour equilibration, 30 min of three vessel occlusion, then release of the contralateral common carotid artery (CCA) for 2.5 h. RESULTS: Induction of ischemia resulted in a 30-fold increase in dopamine release in the lateral striatum. Compared to the nonischemic striatum, the ratio of the hydroxylation product 3,4-dihydroxybenzoate (34DHB) to 4HB (trapping agent) in the ipsilateral striatum increased significantly 30 min after ischemia induction. In contrast, during the 30 min of three vessel occlusion there was no increase in the ratio in the cortex. Following the release of the contralateral CCA, the ratio from the ischemic cortex increased significantly compared to sham-operated animals. However, under all circumstances, the 34DHB/4HB ratio was greater in the striatum than in the cortex. CONCLUSION: The increase in the 34DHB/4HB ratio in the lateral striatum coincides with the increased dopamine release suggesting a role for dopamine oxidation in the increased production of hydroxyl radicals. The significant increase in the ratio from the ischemic cortex compared to that from the sham-operated animals is consistent with increased oxidative stress induced by ischemia. However, the lower 34DHB/4HB ratio in the cortex which does not receive dopaminergic innervation compared to the striatum suggests a different mechanism for hydroxyl radical production. Such an alternate mechanism may represent a more toxic oxidative insult that contributes to infarction.

Vigabatrin as add-on therapy for adult complex partial seizures: a double-blind, placebo-controlled multicentre study. The Canadian Vigabatrin Study Group.

Vigabatrin (VGB) is a novel antiepileptic drug effective as adjunctive therapy in patients with partial seizures. In this study, the efficacy and tolerability of VGB as adjunctive therapy were evaluated in patients with refractory epilepsy. Adult patients with a definite diagnosis of complex partial seizures and/or partial seizures secondarily generalized were recruited from 10 Canadian centres. Patients were randomized to receive either active medication or placebo in a double- blind fashion and entered a 36-week titration and maintenance phase with regularly scheduled visits. Both efficacy parameters and safety assessments were monitored. Clinical laboratory, evoked potential studies, MRI, and neuropsychological tests were also performed. Forty-eight percent of VGB-treated patients vs. 26 percent of placebo-treated patients had a 50 percent or greater reduction in the frequency of complex partial seizures and partial seizures secondarily generalized. Vigabatrin was well tolerated by the majority of patients. Minor neurological side effects were observed in a number of patients in both treatment groups. No serious systemic toxicity was observed. No changes in evoked potential studies or MRI findings were noted. Vigabatrin was found to be an effective and well-tolerated antiepileptic drug when used as adjunctive therapy in patients with difficult to control complex partial seizures and for partial seizures secondarily generalized. Vigabatrin is a selective irreversible inhibitor of the GABA- degradating enzyme GABA transaminase and has shown efficacy in a number of clinical trials in patients with difficult to control partial seizures. Vigabatrin has been found most effective against complex partial and secondarily generalized tonic-clonic seizures in both adults and children. Vigabatrin has also been shown to reduce infantile spasms secondary to various aetiologies and is most effective in spasms associated with tuberous sclerosis. The aim of this study was to further extend the clinical experience with VGB as adjunctive therapy in the treatment of adult patients with difficult to control complex partial seizures and/or partial seizures secondarily generalized. In addition to the assessments of efficacy and tolerability to VGB, neuropsychological evaluations were also carried out.

Local striatal infusion of MPP+ does not result in increased hydroxylation after systemic administration of 4-hydroxybenzoate.

In vivo bilateral microdialysis in the rat striatum was used to investigate hydroxyl radical formation under basal conditions and after intrastriatal administration of the neurotoxin, 1-methyl-4-phenylpyridinium (MPP+). After a short equilibration period, 4-hydroxybenzoate (4HBZ), which scavenges hydroxyl radicals to produce 3,4-dihydroxybenzoate (34DHB), was injected intraperitoneally 15 min before infusion of MPP+. To evaluate the enzymatic contribution to hydroxyl radical formation, two other series of microdialyses were performed following administration of monoamine oxidase B inhibitors, either 1-deprenyl (selegiline) or MDL 72,974A [(E)-2-(4-fluorophenethyl)-3-fluoroallylamine hydrochloride]. Microdialysate samples were analyzed by high-performance liquid chromatography for catecholamines, 3,4-dihydroxyphenylacetate (DOPAC), homovanillate (HVA), along with the hydroxyl radical adduct, 34DHB and its precursor, 4HBZ. MPP+ administration resulted in a massive release of dopamine along with a decrease in DOPAC and HVA in all three groups. A striking effect in all three groups was noted in which MPP+ resulted in a decrease in interstitial 4HBZ to < 50% of the non-MPP+ -treated side. In absolute terms, the amount of 34DHB produced was low but similar in all three groups, even after unilateral MPP+ infusion. When 34DHB was normalized to 4HBZ release to account for differences in precursor availability, there were no significant differences in the 34DHB/4HBZ ratios either with or without MAO inhibitor treatment or after local MPP+ infusion. Systemic 4HBZ administration appears to result predominantly in intra-cellular sampling of hydroxyl radicals which produces different results from local infusion of trapping agents such as salicylate.

Life expectancy and causes of death in a population treated for serious mental illness.

OBJECTIVE: This cross-sectional mortality linkage study describes the prevalence of specific fatal disease and injury conditions in an adult population with serious mental illness. The large sample of decedents and the use of multiple-cause-of-death data yield new clinical details relevant to those caring for persons with serious mental illness. METHODS: Age-adjusted frequency distributions and years of potential life lost were calculated by gender and causes of death for persons in the population of 43,274 adults served by the Massachusetts Department of Mental Health who died between 1989 and 1994. Means and frequencies of these variables were compared with those for persons in the general population of the state who did not receive departmental services and who died during the same period. RESULTS: A total of 1,890 adult decedents served by the department of mental health were identified by electronic linkage of patient and state vital records. They had a significantly higher frequency of deaths from accidental and intentional injuries, particularly poisoning by psychotropic medications. Deaths from cancer, diabetes, and circulatory disorders were significantly less frequently reported. On average, decedents who had been served by the department of mental health lost 8.8 more years of potential life than decedents in the general population-a mean of 14.1 years for men and 5.7 for women. The differential was consistent across most causes of death. CONCLUSIONS: Findings in this study are consistent with previous findings identifying excess mortality in a population with serious mental illness. The high rate of injury deaths, especially those due to psychotropic and other medications, should concern providers.

Pediatric tuberculosis: clinical presentation and contact investigation at an urban medical center.

OBJECTIVE: (A) To characterize the clinical presentation of pediatric tuberculosis in Los Angeles County; (B) to determine the efficacy of contact investigation in identifying a source case for children with tuberculosis. METHODS: We reviewed the medical records, chest radiograph and Tuberculosis Control records of 34 children (age < 15 years) evaluated at Los Angeles County from January 1992 through December 1993. RESULTS: All patients were Hispanic. The mean age was 2.2 years. Thirty-three patients (97%) had intrathoracic disease. Eighteen patients (53%) were symptomatic and the most common symptoms were fever and cough. The contact investigation revealed only 4 patients (2%) to be adult source cases with active tuberculosis. CONCLUSION: The clinical features of pediatric tuberculosis in Los Angeles County confirm results previously reported in other parts of the US. In contrast, the identification of adult source cases is suboptimal. Improved methods of contact tracing are needed when evaluating children with tuberculosis.

Demonstration of avulsion of the triceps tendon in an adolescent by magnetic resonance imaging.

Avulsion of the triceps tendon is an uncommon injury typically occurring in skeletally mature individuals. Although the diagnosis can be suggested by the physical findings and initial radiographs, it may be missed, especially when severe swelling of the soft tissues prevents an accurate physical examination and the radiographs do not show a small fragment of bone accompanying the avulsed tendon. This report describes an avulsion of the triceps tendon in an adolescent boy. Magnetic resonance imaging was useful in confirming the diagnosis.

In vivo hydroxylation of the neurotoxin, 1-methyl-4-phenylpyridinium, and the effect of monoamine oxidase inhibitors: electrospray-MS analysis of intra-striatal microdialysates.

The neurotoxin 1-methyl-4-phenylpyridinium (MPP+) has been shown to increase hydroxyl radical formation in the striatum. The production of hydroxyl radicals correlates with the MPP(+)-driven dopamine release which presumably leads to increased metabolism via monoamine oxidase or increased dopamine autoxidation. Both processes result in enhanced production of hydrogen peroxide, which in the presence of iron(II) ions decomposes to the hydroxyl radical. Monoamine oxidase inhibitors decrease the production of hydroxyl radicals as measured by salicylate and 4-hydroxybenzoate trapping. As both MPP+ and monoamine oxidase inhibitors, such as deprenyl and MDL-72,974A, possess aromatic rings, hydroxyl radical adduct formation was investigated in vitro in defined Fenton systems and also in vivo using intra-striatal microdialysis to infuse MPP+ to rats pretreated systemically with either deprenyl or MDL-72,974A. Electrospray mass spectrometric analysis, using full-scan, fragment ion and constant neutral loss spectra, demonstrated ring hydroxylation of all three compounds in the Fenton systems. Spectral comparison of microdialysis samples with spectra from the Fenton reactions indicated the in vivo hydroxyl radical adduct attachment to MPP+, deprenyl and possibly MDL-72,974A.

Evaluation of sodium 4-hydroxybenzoate as an hydroxyl radical trap using gas chromatography-mass spectrometry and high-performance liquid chromatography with electrochemical detection.

Molecular and tissue damage induced by reactive oxygen species is a serious consequence of the production of free radicals in biological systems. Biological markers produced by reactions with hydroxyl radicals are useful indices of free radical processes in vivo. In this respect, hydroxylation of aromatic compounds such as salicylate (2-hydroxybenzoate) has been used extensively as a measure of hydroxyl radical formation. 4-Hydroxybenzoate will also trap hydroxyl radicals with fewer of the complications for which salicylate has been criticized. We describe two sensitive and specific methods using gas chromatography-ion trap mass spectrometry and high-performance liquid chromatography with electrochemical detection for a number of these aromatic marker compounds in biological fluids. The use of an ion trap mass spectrometer provides enhanced sensitivity along with full mass spectral identification of the compounds of interest. 4-Hydroxybenzoate and salicylate were compared as hydroxyl radical traps (i) by determining relative hydroxyl radical trapping efficiencies in vitro, (ii) by measuring individual dihydroxybenzoate isomers in rat serum following intraperitoneal injection of either 2- or 4-hydroxybenzoate, and (iii) by comparing in vivo hydroxyl radical trapping using intrastriatal microdialysis in the rat. The techniques described have broad applications in the area of free radical biomedical research.

Hydroxylation of aromatic compounds as indices of hydroxyl radical production: a cautionary note revisited.

While setting up an intracerebral microdialysis system to estimate the extent of oxidative stress induced by the neurotoxin, N-methylphenylpyridinium ion (MPP+), we encountered a problem in the use of hydroxybenzoic acids as traps of hydroxyl radicals. Using either 2-hydroxybenzoate (salicylate) or 4-hydroxybenzoate as trapping agents, we observed a nonspecific, that is, nontissue derived, production of hydroxyl radicals as measured by the hydroxylation products, 2,3- and 2,5-dihydroxybenzoate from 2-hydroxybenzoate and 3,4-dihydroxybenzoate from 4-hydroxybenzoate. This production of dihydroxybenzoates was 10 times that expected due to the administration of MPP+, thus making it impossible to interpret our results. Careful investigation of the various components of the microdialysis system indicated that contact of the microdialysate with metal surfaces resulted in dihydroxybenzoic acid formation. These results should serve as a reminder to perform stringent tests of the experimental system prior to experiments with biological tissues to evaluate the contribution of hydroxyl radical production from nonbiological sources. Therefore, along with the possibility of enzymatic production of dihydroxybenzoates, artefactual production by components of the experimental apparatus must be considered before assuming that one is measuring hydroxyl radical production by a biological system.

Dose frequency and dose interval compliance with multiple antiepileptic medications during a controlled clinical trial.

Compliance with medication regimens and clinical trial schedules was evaluated during a study of vigabatrin (VGB), an antiepileptic drug (AED). Medication Event Monitors (MEMS, Aprex Corp., Fremont, CA, U.S.A.) were provided to monitor use of VGB and other AEDs administered to 111 patients at 10 sites. MEMS reports showed the number of doses administered daily, times of doses, and intervals between doses. The 66 patients whose data were evaluable took VGB as prescribed (twice daily, b.i.d.) on 89 +/- 7% of days in the clinical trial (mean 189 +/- 63 days). However, only 66 +/- 24% of doses were taken within the 9-15-h dose interval window for twice-daily dosing, a lower rate than that for dose frequency compliance (p < 0.001). Concomitant medications prescribed b.i.d. (n = 66) (86 +/- 11% dose frequency compliance) were taken at lower rates than VGB (p < 0.02). Interval compliance also was lower for concomitant b.i.d. medications (59 +/- 26%) than for VGB (p < 0.01). Dose frequency compliance for thrice-daily (t.i.d.) medications (n = 36) was 80 +/- 18 and 40 +/- 19% for interval compliance (6-10 h) (both p < 0.0001 vs. VGB). Dose frequency compliance for four times daily (q.i.d.) medications (n = 23) was 80 +/- 23 and 33 +/- 18% for interval compliance (4-8 h) (both p < 0.0001 vs. VGB). Patients at eight sites did not use MEMS properly, often for practical reasons, voiding including of data for 93 medications (32%) because of noncompliance with the study design to monitor compliance.(ABSTRACT TRUNCATED AT 250 WORDS)

Real-time ultrasonography of arterial IVH in preterm infants.

The vascular origin of intraventricular hemorrhage in premature infants is controversial and has been variously attributed to arteries, veins, arterioles, capillaries, or sinusoids that may be found in the vicinity of the ganglionic eminence. The clinical histories and serial ultrasound images are reported from 2 patients with intraventricular hemorrhage of arterial (high pressure) origin that were captured on real-time ultrasonography as they occurred.

Tuberculosis in patients with human immunodeficiency virus infection. How often does it mimic Pneumocystis carinii pneumonia?

Adjunctive corticosteroid therapy is recommended for selected human immunodeficiency virus (HIV)-infected patients with presumed Pneumocystis carinii pneumonia. Because corticosteroids may exacerbate undiagnosed tuberculosis, we evaluated the frequency with which tuberculosis in HIV-infected patients mimics P carinii pneumonia. Over a 12-month period, we identified 105 HIV-infected patients with pleuropulmonary tuberculosis and 84 patients with P carinii pneumonia who were sufficiently hypoxemic to warrant corticosteroid therapy. Of the 105 patients with tuberculosis, acid-fast smears of clinical samples were positive in 49 cases, and chest roentgenographic findings suggested tuberculosis in an additional 44 cases. The 12 patients with negative acid-fast smears and nonspecific chest roentgenographic findings presented a potential diagnostic dilemma between tuberculosis and P carinii pneumonia. Pneumocystis carinii pneumonia should not have been a presumptive diagnosis of eight of these 12 patients because of absence of pulmonary symptoms and chest roentgenographic abnormalities (four cases), a CD4 count greater than 500/cu mm (three cases), or marked lymphadenopathy suggestive of tuberculosis (one case). Thus, only 4 percent (4/105) of HIV-infected patients with pleuropulmonary tuberculosis had clinical and chest roentgenographic features mimicking P carinii pneumonia. Two of these four patients were sufficiently hypoxemic to warrant corticosteroid therapy. Thus, if corticosteroids had been routinely used during the study period, 84 patients with P carinii pneumonia would have been treated, including two patients with undiagnosed tuberculosis. We conclude that the use of corticosteroids for presumed P carinii pneumonia carries a small but acceptable risk of inadvertent exacerbation of tuberculosis, provided clinical and chest roentgenographic features do not suggest tuberculosis.