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Two cases of haemorrhagic diathesis are described, where the laboratory diagnosis was confused owing to previous blood transfusions. Without the help of investigating the relatives, the nephew of Case 1, the haemophiliac, and the uncle of Case 2, with Christmas disease, there would have been considerable delay in reaching the diagnosis and so instituting the correct treatment.
Serum creatine kinase, lactate dehydrogenase, aspartate and alanine transaminases, and aldolase were determined in 41 hospital inpatients with haemophilia or Christmas disease and no significant differences from the normal ranges were found.(3) Levels of these enzymes in a further 10 such patients who had sustained muscle haematomata were determined: in all of these there was a consistent rise in the level of creatine kinase, the peak occurring between 36 and 96 hours. In bleeding disorders a rise in serum creatine kinase levels may be useful as a diagnostic test for intramuscular haemorrhage.
Electroencephalography has been performed in a series of patients with haemophilia and Christmas disease because of the suggestion by other authors of a high incidence of abnormality. In an adult population of haemophiliacs no difference was found in the incidence of abnormalities compared with the general hospital population.
BACKGROUND: Research published in Circulation has shown that cardiac mortality is highest during December and January. We investigated whether some of this spike could be ascribed to the Christmas/New Year's holidays rather than to climatic factors. METHODS AND RESULTS: We fitted a locally weighted polynomial regression line to daily mortality to estimate the number of deaths expected during the holiday period, using the null hypothesis that natural-cause mortality is unaffected by the Christmas/New Year's holidays. We then compared the number of deaths expected during the holiday period, given the null hypothesis, with the number of deaths observed. For cardiac and noncardiac diseases, a spike in daily mortality occurs during the Christmas/New Year's holiday period. This spike persists after adjusting for trends and seasons and is particularly large for individuals who are dead on arrival at a hospital, die in the emergency department, or die as outpatients. For this group during the holiday period, 4.65% (+/-0.30%; 95% CI, 4.06% to 5.24%) more cardiac and 4.99% (+/-0.42%; 95% CI, 4.17% to 5.81%) more noncardiac deaths occur than would be expected if the holidays did not affect mortality. Cardiac mortality for individuals who are dead on arrival, die in the emergency department, or die as outpatients peaks at Christmas and again at New Year's. These twin holiday spikes also are conspicuous for noncardiac mortality. The excess in holiday mortality is growing proportionately larger over time, both for cardiac and noncardiac mortality. CONCLUSIONS: Our findings suggest that the Christmas/New Year's holidays are a risk factor for cardiac and noncardiac mortality. There are multiple explanations for this association, including the possibility that holiday-induced delays in seeking treatment play a role in producing the twin holiday spikes.
Human Factor IX (Christmas factor) is a single-chain plasma glycoprotein (mol wt 57,000) that participates in the middle phase of the intrinsic pathway of blood coagulation. It is present in plasma as a zymogen and is converted to a serine protease, Factor IXabeta, by Factor XIa (activated plasma thromboplastin antecedent) in the presence of calcium ions. In the activation reaction, two internal peptide bonds are hydrolyzed in Factor IX. These cleavages occur at a specific arginyl-alanine peptide bond and a specific arginyl-valine peptide bond. This results in the release of an activation peptide (mol wt approximately equal to 11,000) from the internal region of the precursor molecule and the generation of Factor IXabeta (mol wt approximately equal to 46,000). Factor IXabeta is composed of a light chain (mol wt approximately equal to 18,000) and a heavy chain (mol wt approximately equal to 28,000), and these chains are held together by a disulfide bond(s). The light chain originates from the amino terminal portion of the precursor molecule and has an amino terminal sequence of Tyr-Asn-Ser-Gly-Lys. The heavy chain originates from the carboxyl terminal region of the precursor molecule and contains an amino terminal sequence of Val-Val-Gly-Gly-Glu. The heavy chain of Factor IXabeta also contains the active site sequence of Phe-Cys-Ala-Gly-Phe-His-Glu-Gly-Arg-Asp-Ser-Cys-Gln-Gly-Asp-SER-Gly-Gly-Pro. The active site serine residue is shown in capital letters. Factor IX is also converted to Factor IXaalpha by a protease from Russell's viper venom. This activation reaction, however, occurs in a single step and involves only the cleavage of the internal arginyl-valine peptide bond. Human Factor IXabeta was inhibited by human antithrombin III by the formation of a one-to-one complex of enzyme and inhibitor. In this reaction, the inhibitor was tightly bound to the heavy chain of the enzyme. These data indicate that the mechanism of activation of human Factor IX and its inhibition by antithrombin III is essentially identical to that previously shown for bovine Factor IX.
Human Factor IX (Christmas factor) was isolated from the plasma of a patient with mild hemophilia B. The patient's plasma contained 5% Factor IX clotting activity but 100% Factor IX antigenic activity as determined by immunological assays, which included inhibitor neutralization and a radioimmunoassay for Factor IX. This abnormal Factor IX is called Factor IX Chapel Hill (Factor IXCH). Both normal Factor IX and Factor IXCH have tyrosine as the NH2-terminal amino acid. The two proteins have a similar molecular weight, a similar amino acid analysis, the same number of gamma-carboxyglutamic acid residues (10 gamma-carboxyglutamic acid residues), and a similar carbohydrate content. Both exist as a single-chain glycoprotein in plasma. The major difference between normal Factor IX and Factor IXCH is that the latter exhibits delayed activation to Factor IXa in the presence of Factor XIa and Ca2+. Thus, Factor IXCH differs from other previously described abnormal Factor IX molecules.
Three males with factor-IX deficiency (Christmas disease) in one pedigree all had severe affective disorder. This apparent cosegregation, if true, would support the hypothesis that in some pedigrees, a gene for major affective disorder is located on the X chromosome.
Land crabs produce isosmotic urine but reduce salt loss by reabsorbing salt via the gills to produce a dilute excretory fluid (P). This branchial salt reclamation is regulated in response to changes in dietary salt availability. The regulation of branchial Na reabsorption and osmotic status was investigated in the terrestrial crab Gecarcoidea natalis on Christmas Island. Confinement within field enclosures had no general effect on salt and water balance compared with crabs free in the rainforest but there were seasonal effects. Extracellular fluid volume was 27.9% body mass during the wet season but only 22.7% in the dry season. Urine production was 53 ml kg(-1) day(-1) in the dry season but 111 ml kg(-1) day(-1) in the wet season, while water flux rates were 140 ml kg(-1) day(-1) and 280 ml kg(-1) day(-1), respectively. Serotonin but not dopamine increased urine production by at least 16% but only during the dry season when rates were seasonally lowered. Crabs acclimated to drinking 50% seawater increased haemolymph osmotic pressure and downregulated branchial reabsorption of salt. Net Na flux (J(net)) and unidirectional Na influx (J(in)) were investigated in branchial perfusion experiments. In red crabs acclimated to drinking freshwater, J(in), J(net) and the activity of the Na(+)/K(+)-ATPase were increased by serotonin, indicating that the increase of sodium absorption was due to a stimulation of the ATPase. Red crabs drinking 50% seawater reduced J(net) primarily due to increased passive loss (J(out)), since both J(in) and Na(+)/K(+)-ATPase were unchanged. Serotonin and dopamine abolished the increased diffusive loss and re-established J(net) with no change in J(in). G. natalis exhibits different regulatory systems. Branchial salt uptake can be adjusted via the leak component when adequate salt is available but also by stimulated active uptake under diluting conditions. The gills are important sites of ion pumping in euryhaline aquatic crabs, and the upregulation of J(net) in red crabs is reminiscent of that in marine crabs. Serotonergic stimulation of branchial uptake, independent of cAMP, and hormonally modulated ion leakage are presently unique to terrestrial species.
The respiratory and circulatory physiology of the terrestrial Christmas Island red crab Gecarcoidea natalis was investigated with respect to exercise in the context of its annual breeding migration. Red crabs were allowed to walk for predetermined periods of up to 45 min. During this exercise period, blood gas measurements were made on venous, pulmonary and arterial samples to assess the function of the lungs in gas exchange and the performance of the circulatory system in gas transport and to determine the role and importance of the haemocyanin. The lungs of G. natalis were very efficient at O2 uptake, pulmonary blood being 80­90 % saturated throughout the 45 min exercise period. The maximum O2-carrying capacity was 1.1 mmol l-1, and haemocyanin (Hc) delivered 86 % of oxygen in resting crabs and 97 % during exercise. Oxygen delivery to the tissues was diffusion-limited during exercise. Indirect evidence, from the changes in haemolymph pH during transit through the lungs, suggested that the lung is the site of CO2 excretion. The Bohr shift was high at high pH (pH 7.8­7.5, phi=-1.23) but decreased at low pH (pH 7.1­6.8, phi=-0.48). The decreased Hc affinity for O2 during the exercise period facilitated O2 delivery to the tissues without impairing O2 loading at the lungs. The decrease in pH was sufficient to explain the change of affinity of Hc for O2 during the exercise period. The marked acidosis (0.8 pH unit decrease) was largely metabolic in origin, especially during sustained locomotion, but less than could be predicted from concomitant lactate production.
The respiratory and circulatory physiology of exercising Christmas Island red crabs Gecarcoidea natalis were investigated with respect to their annual breeding migration. Red crabs were allowed to walk for up to 45 min. During this exercise period, the functioning of the circulatory system in gas transport and the energy status of the red crabs were quantified. Energy production during exercise required both aerobic and anaerobic contributions. The aerobic scope of G. natalis was low, with only a doubling of the resting rate of oxygen consumption (resting M(dot)O2=95±15 µmol kg-1 min-1). Maximal O2 consumption was attained within the first 5 min of exercise and the level remained stable thereafter. The anaerobic contribution to energy production was directly related to the speed of locomotion. l-lactate levels in blood and leg muscle were similar throughout the exercise period; blood lactate concentration was 33.39±2.29 mmol l-1 after 45 min of exercise. Heart rate in resting animals was 56±7 beats min-1. At the onset of exercise, heart rate also doubled, but without a significant increase in cardiac output. Increased O2 delivery was facilitated by increased extraction from the blood. During the 45 min of exercise, glucose levels increased rapidly in the muscle tissue (from 2.30±0.54 to 8.78±1.20 mmol l-1) and subsequently in the blood (from 1.22±0.26 to 2.12±0.17 mmol l-1), fuelling increased glycolysis during locomotion. The energy production from stored glucose/glycogen was sufficient to support the energetic needs of locomotion, since the energy charge remained stable at 0.82. Haemolymph l-lactate levels in crabs sampled in the field after migration were high compared with levels in many crustacean species but equivalent to l-lactate levels in laboratory animals exercised for less than 10 min. During their migration, therefore, the red crabs avoid exceptional l-lactate build-up in the blood by either walking very slowly or intermittently. However, G. natalis are exceptionally well adapted to cope with exhaustive locomotion and the resultant severe metabolic acidosis.
Crabs generally produce urine iso-osmotic to their haemolymph, but terrestrial crabs are able to vary the composition of their final excretory fluid (termed P) postrenally, in the branchial chambers. Regulatory aspects of branchial urine processing were investigated in the Christmas Island red crab Gecarcoidea natalis acclimated to drinking either freshwater (FW crabs) or 70% seawater (SW crabs). FW crabs released dilute P (mean [Cl(-)] 8.8 mmol l(-1)). Drinking 70% seawater caused the mean [Cl(-)] of the P to rise to 376 mmol l(-1) over 5 days, approaching the haemolymph [Cl(-)]. FW crabs with saline-perfused branchial chambers absorbed chloride at a high rate (10 mmol kg(-1) h(-1)), and haemolymph [Cl(-)] increased at approximately 20 mmol l(-1) h(-1). SW crabs exhibited elevated haemolymph osmolalities and ion concentrations and zero branchial chloride uptake. FW crabs that were salt-loaded by branchial chamber perfusion over several hours downregulated, and eventually ceased, chloride uptake. The rate of downregulation, but not the initial chloride flux, was dependent on initial haemolymph [Cl(-)]. Intravascular infusion of NaCl caused immediate reduction in branchial [Cl(-)] of 80%. Crabs ingested and regurgitated the perfusion saline, supporting suggestions that reingestion of urine could conserve water and ions. Dopamine upregulated branchial chloride transport in G. natalis. This is consistent with the ion-regulatory effects of dopamine in euryhaline marine brachyurans but contrasts with its inhibitory effects in the terrestrial anomuran Birgus latro. Dopamine increased the rate of urine release in FW crabs. Urine composition appears to be unimportant in ionic regulation, except in the case of magnesium, levels of which were elevated in the urine of SW crabs.
We evaluated a 29-year-old candy maker with no history of asthma who developed asthma after exposure to pectin, a compound manufactured from fruits and fruit rinds. Following eight years of employment during which he added pectin to a recipe for Christmas candies, the candymaker developed acute respiratory symptoms. Challenge testing with the pectin mixture caused a 40 percent decrease in FEV1. Skin prick testing was positive to the pectin extract. Total IgE was normal and pectin-specific IgE antibodies were not detected. A strongly positive pectin-specific IgG4 antibody response was present that was not detected in a control serum and could be inhibited by the addition of pectin. Antigen-specific IgG4 should be sought in IgE negative cases of occupational asthma.
The terrestrial crab Gecarcoidea natalis is endemic to the forests of Christmas Island but must migrate each year to the coast to breed. During 1993 and 1995, radio-tracking, mark and recapture, and counting methods were used to establish the routes, walking speeds, direction of travel, and destinations of migrating crabs, as well as crab numbers and distribution. The density of crabs ranged from 0.09 to 0.57 crabs per square meter, which gave a population estimate of 43.7 million adult crabs on the island. During the dry season the crabs were relatively inactive but on arrival of the wet season immediately began their migration. The crabs generally walked in straight lines, and most crabs from around the Island traveled toward the northwest shore instead of simply walking toward the nearest shore. The maximum recorded distance walked by a red crab in one day was 1460 m, but the mean was 680 m per day in 1993 and 330 m in 1995. Comparing the 1993 and 1995 study seasons, there was a 3-week difference in the timing of the start of the migration, but the spawning date was fixed by the lunar phase and took place 17 to 18 days after mating. In 1993, late rain prompted a "rushed" migration and crabs walked directly to their shore destinations; in contrast, in 1995 most crabs made stops of 1 to 7 days during the downward migration. By giving the crabs a chance to feed along the way and minimizing the time that the population was concentrated near the shore, these stops may be important in ensuring that the animals have enough food after the long dry season. Furthermore, this behavior implies that the crabs are able to judge how far away they are from the shore during the migration.
Sporotrichosis was diagnosed in a 2-year-old male Golden Retriever that was allowed to roam free on the owner's Christmas tree farm in Minnesota. Clinical signs had been evident for 1 month and included swelling of the claw bed of the third digit on the left forelimb and a fluctuant nodular lesion in the area of the left carpus. Few organisms were seen in affected tissues, and diagnosis was confirmed on the basis of results of fungal culture. The condition responded to treatment with itraconazole. Previous reports of sporotrichosis in dogs have described lesions that were distributed predominantly on the head, ears, and trunk. A history of exposure to environments that favor survival of the organism may be an important consideration when evaluating animals suspected to have sporotrichosis. To the authors' knowledge, use of itraconazole to treat a dog with sporotrichosis has not been reported previously.
In a total of 590 Christmas cards sent perception of status was important for both the sender and the receiver. High status of the sender increased the response rate significantly, especially among the "blue-collar" receivers.
OBJECT: The authors compared differences in biomechanical stability between two decompressive laminectomy techniques for treating lumbar stenosis. A Christmas tree laminectomy (CTL), in which bilateral facetectomies and foraminotomies are performed, was compared with facet-sparing laminectomy (FSL), in which the facets are undercut but not resected. Spinal instability was assessed immediately postoperatively and again after discectomy to model long-term degeneration. METHODS: Sixteen motion segments obtained from five human cadaveric lumbar specimens were studied in vitro by conducting nondestructive flexibility tests. Specimens were tested intact, after FSL or CTL, and again after discectomy. Nonconstraining torques (< or = 5 Nm) were applied to induce flexion, extension, axial rotation, and lateral bending; strings and pulleys were used while vertebral angles were measured. Anteroposterior translation in response to shear loading (< or = 100 N) was also measured. Angular motion, shear motion, and sagittal-plane axes of rotation were compared to evaluate stability. Compared with the intact condition, CTL-treated specimens had significantly larger increases in angular motion during flexion, lateral bending, and axial rotation than their FSL-treated counterparts (p < 0.05, nonpaired Student t-tests). Subsequent discectomy caused greater increases in motion in the CTL group. Axes of rotation shifted less from their normal positions after FSL than after CTL. CONCLUSIONS: This study provides objective evidence that the treatment of lumbar stenosis with FSL induces less biomechanical instability and alters kinematics less than FSL. These findings support the use of the FSL in treating lumbar stenosis.
The term "Christmas eye" is one I have coined to describe a type of acute corneal erosion which seems to occur only between late November and mid January, in country areas of New South Wales. Since 1970, I have seen 20 cases, all monocular, in people from an area bounded by Wellington, Mudgee, Grenfell, Cowra and Young. Twelve patients were adult males, three were adult females, and there were five children (one female, four male). The incidence varies; six cases presented in 1976, and none in 1978.
A case combining Christmas disease and tricuspid atresia is presented. A severe coagulation defect in a hypoxic, polycythemic patient poses an added grave risk to major surgery. In the presence of marked and worsening symptoms, however, major surgery can be performed in these difficult cases. Close liason with a skilled hematology department is essential. Minimal tissue dissection is advised, and the usefulness of a reversed saphenous vein conduit is described.