[Anaerobiosis beyond anaerobic bacteria: its role in the recovery of aerobic microorganisms from purulent samples]. / La anaerobiosis más allá de las bacterias anaerobias: su importancia en la recuperación de microorganismos aerobios a partir de materiales purulentos.

The main objective of incubation in anaerobiosis is the recovery of obligate anaerobic bacteria, not excluding other microorganisms. In 2003, we conducted a comparative and prospective study from consecutive clinical samples on the recovery of aerobic microorganisms from primary cultures both in anaerobiosis and aerobiosis of the same sample. The aims were to evaluate the methodology used in anaerobiosis in the recovery of aerobic microorganisms not diagnosed in primary aerobic cultures, and to establish a relationship between them and the origin of the sample. From 2003 to 2004, 2776 bacteriological samples were analyzed and 1884 aerobic microorganisms were cultured altogether. The result was that 69.4% of the samples showed growth both in aerobic and anaerobic incubation from primary cultures of the sample, whereas 30.6% only in one of the mentioned incubation atmosphere: 49.2% in aerobiosis and 50.8% in anaerobiosis. According to these results, the methodology used in anaerobiosis (anaerobic incubation, culture media, stereoscopic microscope or hand lens to examine the primary plates), allowed an extra yield of aerobic organisms, especially gram positive facultative and microaerophilic cocci, which was particularly evident in polimicrobial cultures, and especially when gram negative accompanying flora was present, independently of the type of sample.

Molecular weight of hydroxyethyl starch: is there an effect on blood coagulation and pharmacokinetics?

BACKGROUND: The development of hydroxyethyl starches (HES) with low impact on blood coagulation but higher volume effect compared with the currently used HES solutions is of clinical interest. We hypothesized that high molecular weight, low-substituted HES might possess these properties. METHODS: Thirty pigs were infused with three different HES solutions (20 ml kg(-1)) with the same degree of molar substitution (0.42) but different molecular weights (130, 500 and 900 kDa). Serial blood samples were taken over 24 h and blood coagulation was assessed by Thromboelastograph analysis and analysis of plasma coagulation. In addition, plasma concentration and in vivo molecular weight were determined and pharmacokinetic data were computed based on a two-compartment model. RESULTS: Thromboelastograph analysis and plasma coagulation tests did not reveal a more pronounced alteration of blood coagulation with HES 500 and HES 900 compared with HES 130. In contrast, HES 500 and HES 900 had a greater area under the plasma concentration-time curve [1542 (142) g min litre(-1), P<0.001, 1701 (321) g min litre(-1), P<0.001] than HES 130 [1156 (223) g min litre(-1)] and alpha half life (t(alpha)(1/2)) was longer for HES 500 [53.8 (8.6) min, P<0.01] and HES 900 [57.1 (12.3) min, P<0.01] than for HES 130 [39.9 (10.7) min]. Beta half life (t(beta)(1/2)), however, was similar for all three types of HES [from 332 (100) to 381 (63) min]. CONCLUSIONS: In low-substituted HES, molecular weight is not a key factor in compromising blood coagulation. The longer initial intravascular persistence of high molecular weight low-substituted HES might result in a longer lasting volume effect.

A novel promoter polymorphism in the gene encoding complement component 5 receptor 1 on chromosome 19q13.3 is not associated with asthma and atopy in three independent populations.

BACKGROUND: The inflammatory functions of complement component 5 (C5) are mediated by its receptor, C5R1, which is expressed on bronchial, epithelial, vascular endothelial and smooth muscle cells. A susceptibility locus for murine allergen-induced airway hyper-responsiveness was identified in a region syntenic to human chromosome 19q13, where linkage to asthma has been demonstrated and where the gene encoding C5R1 is localized. OBJECTIVE: The aim of this study was to screen for novel polymorphisms in the C5R1 gene and to determine whether any identified polymorphisms are associated with asthma and/or atopy and whether they are functional. METHODS: Single-nucleotide polymorphism (SNP) detection in the gene encoding C5R1 was performed by direct sequencing. Genotyping was performed in three populations characterized for asthma and/or atopy: (1) 823 German children from The Multicenter Allergy Study; (2) 146 individuals from Tangier Island, Virginia, a Caucasian isolate; and (3) asthma case-parent trios selected from 134 families (N=783) in Barbados. Functional studies were performed to evaluate differences between the wild-type and the variant alleles. RESULTS: We identified a novel SNP in the promoter region of C5R1 at position -245 (T/C). Frequency of the -245C allele was similar in the German (31.5%) and Tangier Island (36.3%) populations, but higher in the Afro-Caribbean population (53.0%; P=0.0039 to <0.0001). We observed no significant associations between the -245 polymorphism and asthma or atopy phenotypes. Upon examination of the functional consequences of the -245T/C polymorphism, we did not observe any change in promoter activity. CONCLUSION: This new marker may provide a valuable tool to assess the risk for C5a-associated disorders, but it does not appear to be associated with asthma and/or atopy.

Vacuum assisted venous drainage does not increase trauma to blood cells.

Although gravity drainage has been the standard technique for cardiopulmonary bypass (CPB), the development of min imally invasive techniques for cardiac surgery has renewed interest in using vacuum assisted venous drainage (VAVD) Dideco (Mirandola, Italy) has modified the D903 Avant oxygenator to apply a vacuum to its venous reservoir. The impact of VAVD on blood damage with this device is analyzed. Six calves (mean body weight, 71.3 +/- 4.1 kg) were con nected to CPB by jugular venous and carotid arterial cannu lation, with a flow rate of 4-4.51 L/min for 6 h. They were assigned to gravity drainage (standard D903 Avant oxygen ator, n = 3) or VAVD (modified D903 Avant oxygenator, n = 3). The animals were allowed to survive for 7 days. A standard battery of blood samples was taken before bypass, throughout bypass, and 24 h, 48 h, and 7 days after bypass. Analysis of variance was used for repeated measurements. Thrombocyte and white blood cell counts, corrected by hematocrit and normalized by prebypass values, were not significantly different between groups throughout all study periods. The same holds true for hemolytic parameters (lactate dehydrogenase [LDH] and plasma hemoglobin). Both peaked at 24 hr in the standard and VAVD groups: LDH, 2,845 +/- 974 IU/L vs. 2,537 +/- 476 IU/L (p = 0.65), respectively; and plasma hemoglobin, 115 +/- 31 mg/L vs. 89 +/- 455 mg/L (p = 0.45), respectively. In this experimental setup with prolonged perfusion time, VAVD does not increase trauma to blood cells in comparison with standard gravity drainage.

The prevalence and pattern of liver disease in infants and children in Hazara Division.

BACKGROUND: The pattern of the liver disease may vary in different geographical locations. These reported variations are attributable to the differences in environmental factors, eating habits, socio-economic factors and other reasons. We studied the pattern of liver diseases in infants and children of Hazara Division of Pakistan. METHODS: 200 inpatient and outpatient infants and children in Ayub Teaching Hospital were studied from June, 1998 to October, 1999. RESULTS: The spectrum of defect in the subjects, suffering from liver diseases showed that viral hepatitis was more common (relative frequency of 60%), followed by enteric hepatitis (26%), drug induced liver injury (7.5%), biliary atresia (5.0%) and Criglar-Najjar Syndrome (1.5%). Although both sexes were affected, however, the spectrum of liver disease was more common in males. Moreover, viral hepatitis and enteric hepatitis were found in children aging 6 to 8 years, biliary atresia in 6 months to 2 years, and drug induced liver injury in 3 to 5 years old subjects.

Different ipsilateral representations for distal and proximal movements in the sensorimotor cortex: activation and deactivation patterns.

Each hemisphere is known to be also involved in controlling the ipsilateral arm, but with an asymmetry favoring the dominant hemisphere. However, the relative role of primary and secondary motor areas in ipsilateral control is not well defined. We used whole brain functional magnetic resonance imaging in healthy human subjects to differentiate between contributions from primary and secondary areas during discrete unilateral distal finger and proximal shoulder movements. It was found that ipsilateral distal movements activated secondary areas only, while sparing or even significantly deactivating the primary sensorimotor cortex. Ipsilateral proximal movements substantially activated both SM1 and secondary areas. A newly defined small territory within the precentral gyrus, extending from the premotor cortex and intruding toward SM1, showed an activation pattern corresponding to secondary motor areas. Finally, the effects of hemispheric dominance were confirmed, but attributed exclusively to secondary areas. These new imaging findings agree well with functional requirements as well as established anatomical and neurophysiological data.

Functional organisation of the saccadic reference system processing extraretinal signals in humans.

In order to investigate the neuronal network involved in processing extraretinal signals, functional magnetic resonance imaging (fMRI) was applied to subjects performing the double step saccade paradigm. There, the calculation of the amplitude of the second saccade must rely on extraretinal signals of the first. When compared to a task where both saccades could be performed by means of retinal signals alone, a parieto-frontal cortical network was activated, including lateral intraparietal area, precuneus, insula, inferior frontal gyrus and anterior cingulum.

Performance of a new implantable cardiac assist centrifugal pump.

The AB-180 is a new implantable centrifugal pump with a low volume dome (10 ml) and a local heparin delivery system which avoids systemic heparinization. This study focuses on its hemodynamic performance. We analyzed 3 anesthetized calves (71.0 +/- 2.5 kg), equipped with arterial pressure (AP), and Swan-Ganz and left atrial pressure (LAP) catheters. The AB-180 pump was installed through a left thoracotomy, with a transmitral left ventricular (LV) inflow cannula inserted via the left appendage and an outflow tract sutured to the descending aorta. LAP, AP, and blood flow across the pump were recorded for various pump speed and in different preload conditions (right atrial pressure = 4, 7, and 10 mm Hg, respectively). The pump significantly unloaded the left heart cavities and was able to increase the mean AP. For an RAP of 10 mm Hg, running the pump at 4,500 rpm decreased the LAP from 11.0 +/- 0.8 mm Hg to 3.0 +/- 0.8 mm Hg (p < 0.001) and augmented the mean AP from 48.2 +/- 6.4 mm Hg to 80.8 +/- 12.1 mm Hg (p < 0.001). A maximal pump flow of 5.6 +/- 0.2 L/min was obtained under these conditions. In addition to the advantage of its particular design, the AB-180 can be considered as an efficient left ventricular assist device (LVAD). It significantly unloads the left heart cavities and ensures efficient systemic AP and blood flow.

Prevalence and pattern of congenital heart disease in Hazara.

BACKGROUND: The incidence and particularly the pattern of congenital heart disease may vary in different geographical locations, but the extent to which such reported variations are attributable to differences in genetic predisposition, environmental factors, or in study methodology and diagnostic precision remains uncertain. There is, therefore, a continuing need for studies on various aspects of congenital heart disease, in different communities and races. METHODS: This study was done on 188 consecutive cardiac patients reporting at Ayub Teaching Hospital, Abbottabad, Pakistan from June 1998 to June 2000. RESULTS: 114 of 188 cardiac patients studied had congenital heart disease. Both sexes were equally affected. Ventricular septal defects were the most common lesions (relative frequency 61.4%), followed by Tetrology of Fallots, ASD and PDA with a relative frequency of 8.77%. The detection rate under one month was 28.07% and at one year 75.43%. CONCLUSION: There is therefore, a need for increased awareness, especially among primary health and other front line doctors for earlier case detection.

Ex vivo testing of the Quart arterial line filter.

Arterial line filters are now routinely used in cardiac surgery in order to decrease the microemboli load to the patient. The Quart filter (Jostra, Hirrlingen, Germany) with a new planar construction design, an easy de-airing system and an integrated bypass, was tested for air filtration capacity and resistance to blood path in a standardized setting with surviving animals. Three calves (mean body weight: 71+/-3.4 kg) were connected to a standard cardiopulmonary bypass (CPB) circuit by jugular venous and carotid arterial cannulation with a mean flow rate of 3.5 l/min. The arterial line filter was challenged with upstream injections of boluses of air of 5, 10 and 15 ml, respectively. A Doppler ultrasound was positioned downstream on the arterial line to measure bubble count and size. The pressure drop through the filter was monitored at flow rates of between 1 and 6 l/min. At the end of the procedure the animals were weaned from the CPB and, thereafter, from the ventilator. After 7 days, the animals were sacrificed electively. This study shows that important quantities of air can be injected into the arterial line upstream of the filter with small volumes of small sized bubbles recorded downstream. With the 5 ml air bolus injection, mean values of 0.3+/-0.6 bubbles of 30 and 40 microm were detected, whereas with the 20 ml bolus, 32.6+/-8.7 bubbles of 10 microm, 3.7+/-1.1 bubbles of 30 microm, 3.3+/-0.6 bubbles of 40 microm and 0.7+/-1.1 bubbles of 50 microm were recorded. The blood path resistance at different blood flow rates was well within the acceptable range with a pressure drop of 20+/-0 and 26.6+/-5.7 mmHg at flow rates of 4 and 5 l/min, respectively. With its planar concept, the Quart filter offers good air filtering capacity both in terms of bubble count and size after injection of large boluses of air, without any increase of resistance to the blood path. Moreover, it offers a venting function and an integrated bypass system.

Trillium coating of cardiopulmonary bypass circuits improves biocompatibility.

Coating of cardiopulmonary bypass circuits may be a solution to prevent adverse effects induced by contact of blood elements with foreign surfaces. Using an animal model, we investigated the Trillium TM coating of cardiopulmonary bypass circuits (a new process involving polyethylene oxide, sulphonate groups and heparin) at low systemic heparinization, focusing on haemolysis and clot formation. Cardiopulmonary bypass was initiated through jugulo-carotid access with ACT maintained around 180 sec. Treated circuits (Trillium group) were evaluated in 3 calves (mean weight of 66.0+/-8.7 kg), vs. untreated circuits in 3 control calves (mean weight of 60.7+/-7.5 kg). Blood samples were drawn at regular intervals for biochemical, hematological and blood gas analyses. After 6 consecutive hours, the animals were weaned from CPB and were awakened. The circuits were analyzed for clot deposits. After 7 days the animals were sacrificed and an autopsy was carried out. Red cell and white cell counts did not change over the 6 hours. Platelet counts dropped to 75.9+/-7.3% of the baseline value in the Trillium group after 6 hours whereas counts dropped to 57.2+/-26.0 in the control group (p<0.05). Plasma free Hb remained constant in the Trillium group but increased significantly to 280+/-65% of baseline value in the control group (p<0.05). The amount of clots were significantly higher in the control group, in the connectors, the reservoir, the heat exchanger, and the oxygenator. No renal emboli were seen in the Trillium group whereas the mean number of emboli was 3.0+/-2.4 in the control group. We conclude that Trillium coating significantly improves the biocompatibility of artificial surfaces exposed to blood.

[Prevention of pericardial adhesions with a bioresorbable membrane]. / Prévention des adhérences péricardiques avec une membrane biorésorbable.

A bioresorbable membrane made of sodium hyaluronate and carboxymethycellulose, has been reported to prevent peritoneal adhesion. This study was designed to test its efficiency in the prevention of pericardial adhesions. Two groups of six pigs (mean weight 72 +/- 8 kg) were chosen for the experiment. The heart was exposed through a left thoracotomy and a wide patch of pericardium was excised. In the test group (n = 6), the left ventricular area without pericardium was divided into two areas: area A where six stitches of Prolene were performed, and area B which was left intact. The membrane was applied on the both areas as well as on the adjacent area covered with pericardium (area C). In the control group (n = 6), the same protocol was performed except for the membrane application. The animals were sacrificed one month later. The adhesion status as well as the visibility of the coronary anatomy was assessed according to severity scores ranging from 0 to 3 for the adhesions and from 0 to 2 for the visibility. The difference between groups was considered significant when p < 0.05. The adhesion score of the area A was 1.7 +/- 0.5 in the test group versus 2.5 +/- 0.5 in the control group (p = 0.02) and the visibility score was 1.3 +/- 0.8 and 2 +/- 0 respectively (p = 0.07). In the area B, the adhesion score was 1 +/- 0 in the test group versus 2 +/- 0.6 in the control group (p = 0.03) and the visibility score was 0.7 +/- 0.5 and 2 +/- 0 respectively (p = 0.001). Lastly, in the area C, the adhesion score was 1 +/- 0 in both groups (n.s.) and the visibility score was 0.7 +/- 0.4 in the test group versus 0.5 +/- 0.5 in the control group (n.s.). In this animal model, the role of the bioresorbable membrane in the prevention of pericardial adhesions is limited to the areas without pericardial cover and without foreign material. The presence of foreign material neutralizes its effect.

Air trapping ability of the Spiral Gold membrane oxygenator: an ex vivo study.

Despite an overall improvement in cardiopulmonary bypass (CPB) technology and materials, air emboli still occur. The latest generation membrane oxygenator from Bentley Laboratories, the SpiralGold, was tested ex vivo for its air handling ability. The study was conducted on four calves. Bolus amounts of air of 10, 15 and 20 cm3 were each injected three times, upstream of the oxygenator and a bubble detector located directly downstream. The amount of bubbles was measured semiquantitatively on a 10 unit scale (U one semiquantitative unit). The animals were killed 10 days after the CPB. When 10 cm3 of air was injected, no bubbles were detected. With 15 and 20 cm3, respectively, 1 +/- 1.5 and 5 +/- 3.3 U of bubbles were detected. Despite a total of 135 cm3 of air injected as large bolus amounts, all the animals survived without any obvious neurological deficit secondary to air bubble manipulation. In conclusion, the SpiralGold oxygenator per se can reliably trap an air bolus of up to 10 cm3. This feature should be taken into account when choosing an oxygenator, as it offers an additional barrier to air bubbles in the CPB circuit.

Serum proteins electrophoresis in infants and children.

Total serum proteins and its fractions were estimated in 468 infants and children from birth to 4 years in relation to age, sex and dietary pattern. The mean values of total serum proteins and its fractions showed some changes with age, especially in gamma globulins, which was high at birth and showed a decrease at the age of 3 months, after which it increased and attained an adult level at the age of 18 months. No difference was noted between the two sexes. Completely breast fed infants had a significantly higher protein and albumin levels at 3 months than completely weaned infants but no such difference was observed in other protein fractions in the same age groups.