Observations of the Number of Available c, D, and E Antigen Sites on Red Cells

Abstract. The number of available antigen sites within the Rh system were estimated using trace-labelled antibodies. The results were as follows, given as the number of sites per red cell: c-antigen: on cc cells, 70,000–85,000: on Cc, 37,000–53,000; D sites on cells of phenotype -D-: 110,000–202,000; E-antigen sites showed considerable heterogeneity depending on phenotype as well as source of anti-E, and estimates varied between 450 and 25,600; e-antigen: on eE cells, 13,400 and 14,500: on ee cells, 18,200 and 24,400.
The average equilibrium constants of the antibodies were: anti-E, 4 × 10⁸ 1/mol; anti-e, 2.5 × 10⁸ 1/mol; anti-c, 3.2 × 10⁷ and 5.6 × 10⁷ 1/mol.     

Lupus anticoagulant: a clinical and laboratory study of 100 cases

Summary The clinical and laboratory features of 100 patients with lupus anticoagulant (LA) are reviewed. Subjects were divided into three groups according to their age (1–5, 15–35, 45–89 years). Female prevalence was observed in each group and overall F/M ratio was 3/1. An underlying autoimmune disease (principally lupus erythematosus) was found in 47 cases (10% of the children, 80% of the 15–35-year-old patients and 37% of the elderly patients). Biological criteria for the LA diagnosis were prolonged activated partial thromboplastin time and diluted thromboplastin time (1.3 × control), not corrected after addition of control to patient's plasma. Thromboplastin time was normal in 77 patients. Other types of coagulation inhibitors were eliminated by specific factor assays (with a 10-fold increase of cephalin concentration when necessary). Twenty-three thrombotic episodes were observed. No significant difference was found in the incidence of thrombosis between the autoimmune and non-autoimmune disease group, but the age when first thrombosis occurred was clearly lower in the former. Fourteen obstetrical accidents were noted in eight women but 13 pregnancies terminated without accident. Four patients experienced haemorrhagic complications; they all presented with a severe thrombocytopenia associated with the LA. In our experience, LA is a frequent coagulation abnormality, associated in about half of the cases with a clearly defined autoimmune disease. Clinical presentation appears as notably different according to the patient's age; it is particularly noteworthy that in nine out of 10 children, LA disappeared spontaneously within 6 months.     

Patient Satisfaction and Reported Long-Term Therapeutic Efficacy Associated with 1,320 nm Nd:YAG Laser Treatment of Acne Scarring and Photoaging

BACKGROUND AND OBJECTIVE: Nonablative laser treatments have become increasingly used for the treatment of acne scarring and photoaging. While nonablative laser treatments are more convenient and relatively safer than ablative laser resurfacing, efficacy and patient satisfaction with the level of improvement of textural abnormalities in acne scarring and rhytids associated with photoaging needs further study. DESIGN/MATERIALS AND METHODS: Structured interviews were performed with 34 patients from a referral-based academic practice who each previously received a series of 6 monthly treatments with a 1,320 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser for treatment of acne scarring or photoaging. Topical anesthesia was applied 1 hour before each treatment. Patients were interviewed at least 3 months after cessation of treatment (range 3-12 months). RESULTS: Patients tolerated the treatments well. Combined results for acne scarring and photoaging patients were as follows: (a) patient satisfaction with treatment was rated at 62%, and (b) textural improvement was reported at 31% at the end of the six treatments, and 30% at the date of interview. When results were stratified by diagnosis, patient satisfaction was slightly higher for treatment of acne scarring than for photoaging. Overall degree of improvement on a 1-10 scale was 5.4 for acne scarring and 3.8 for wrinkling. CONCLUSION: Nonablative treatment with the 1,320 nm Nd:YAG laser induced significant patient-reported improvement in both acne scarring and photoaging. The majority of patients reported satisfaction with the degree of improvement.     

SUXAMETHONIUM-INDUCED HYPERKALAEMIA IN PATIENTS WITH SEVERE INTRA-ABDOMINAL INFECTIONS

In nine patients, undergoing repeat operations because of severeintra-abdominal infection developing after major abdominal surgery,serum potassium concentrations were monitored during inductionof anaesthesia. Four patients showed an increase of serum potassiumranging from 2.5 to 3.1 mmol/ litre above baseline values within3–6 min after suxamethonium 100 mg i.v. In five patientsthere was no change. The four patients demonstrating an increasehad suffered from pyrexia and leucocyt-osis for at least 2 weeks.The other five had signs of infection for no more than 9 days.It is concluded that patients with signs of severe intra-abdominalinfection lasting longer than 1 week represent an additionalcategory susceptible to suxamethonium-induced hyperkalaemia.They should receive only non-depolarizing muscle relaxants.When the use of suxamethonium is unavoidable, the injectionof a non-depolarizing muscle relaxant before the administrationof suxamethonium is recommended.     

Valve movement response of the mussel Dreissena polymorpha -- the influence of pH and turbidity on the acute toxicity of pentachlorophenol under laboratory and field conditions

The Dreissena-Monitor is a biological early warning system for the continuous monitoring of water quality, based on the computer assessment of valve movements in two groups of 42 zebra mussels (Dreissena polymorpha). In the laboratory, two series of toxicity tests were conducted with PCP. (1) At neutral pH conditions only the concentration of PCP was altered. The dose--response relationship revealed 15 g l–1 PCP for the number of valve movements and 20 g l–1 PCP for the percentage of open mussels. (2) At 50 g l–1 PCP the pH value was altered from 6.5 to 8.4, demonstrating an inverse relationship between the toxicity of PCP and the pH. The detection limits evaluated from a series of toxicity tests under the field conditions of the River Rhine at Koblenz were nearly ten times higher than those from the laboratory. During a second series of toxicity tests under the field conditions of the River Rhine at Bad Honnef, the toxicity of PCP seemed to be reduced in relation to the increasing turbidity. The differences between the results obtained under laboratory and field conditions are discussed with respect to the influence of the pH and turbidity at the toxicity of PCP on D. polymorpha     

A Split-Face Comparison Study of Pulsed 532-nm KTP Laser and 595-nm Pulsed Dye Laser in the Treatment of Facial Telangiectasias and Diffuse Telangiectatic Facial Erythema

BACKGROUND AND OBJECTIVES: Pulsed 595 nm and 532 nm lasers can effectively diminish or eliminate facial telangiectasia. We performed a split-face, single-blind, controlled, comparison study in an effort to determine their individual and comparative efficacy. STUDY DESIGN/MATERIALS AND METHODS: Fifteen patients were treated using a 595-nm PDL on one side of the face and a pulsed 532-nm potassium-titanyl-phosphate (KTP) laser on the other. Each subject was evaluated at 3 weeks after three treatments. RESULTS: Both devices improved telangiectasia. The 532-nm device, however, was at least as effective or more effective than the 595-nm laser in all subjects. On average, the KTP laser achieved 62% clearing after the first treatment and 85% clearing 3 weeks after the third treatment, compared to 49% and 75% for the PDL, respectively. Seventy-nine percent of KTP laser-treated patients continued to have swelling for greater than 1 day versus 71% of PDL-treated patients. Of those patients who noted persistent erythema for at least 1 day after treatment, 58% noted more erythema on the KTP laser-treated side compared to 8% on the PDL-treated side. CONCLUSIONS: Both the 595-nm and the 532-nm pulsed lasers are highly effective in the treatment of facial telangiectasia and redness. The 532-nm KTP laser appears to be more effective but causes more swelling and erythema.     

Influence of external cardiac pacing on cerebral oxygenation measured by near‐infrared spectroscopy in children after cardiac surgery

Background: The brain of children in the early period after repair of congenital heart defects with cardiopulmonary bypass (CPB) may be more vulnerable to hemodynamic changes because of impaired cerebral autoregulation. During postoperative testing of the external temporary safety pacer, we performed desynchronizing ventricular pacing (VVI) while monitoring cerebral oxygenation using near‐infrared spectroscopy (NIRS). Methods: We prospectively investigated 11 children (6 girls, 5 boys). Mean age was 6.1 months (±3.8 months) and mean weight: 5.3 kg (±1.5 kg). We performed measurements at four study steps: baseline I, VVI pacing, baseline II and atrial pacing (AOO) to exclude effects of higher heart rate. We continuously measured the effects on hemodynamic and respiratory parameters as well as on cerebral tissue oxygenation index (TOI). Hemoglobin difference (HbD) was calculated as a parameter for cerebral blood flow (CBF). Results: Ventricular pacing leads to a significant decrease in arterial blood pressure and central venous saturation accompanied by an immediate and significant decrease in TOI (63.3% ± 7.6% to 61.5% ± 8.4% [P < 0.05]) and HbD (0.51 ± 1.8 μmol·l⁻¹ to −2.9 ± 4.7 μmol·l⁻¹ [P < 0.05]). Conclusion: Cardiac desynchronization after CPB seems to reduce CBF and cerebral oxygenation in children.     

Evidence of validity in a new method for measurement of dexterity in children and adolescents

Aim Many everyday activities involve manipulation of objects with the fingertips. Impaired performance in manipulative tasks is common in neurodevelopmental disorders. Thus accurate assessment of an individual’s ability to coordinate fingertip forces is important for planning treatment. We evaluated a recently developed assessment tool (the Strength–Dexterity Test), which is based on manipulation of unstable objects, in a paediatric population. Method A Rasch model was used to examine the validity and reliability of the Strength–Dexterity Test in a sample of 56 typically developing children and adolescents (30 males, 26 females; age range 4y 10mo–17y 3mo; mean age 9y 8mo, SD 3y 8mo). In addition, we examined how performance on this test relates to widely used tests for assessment of gross manual dexterity (assessed with the Box and Blocks Test) and finger strength measured with a pinch meter. Results The constructs measured with the 78‐item Strength–Dexterity Test include dexterity and strength, and form a unique unidimensional latent trait, named fingertip force coordination, that improves with age. The test has internal scale validity when applied to a typical paediatric population. Positive correlations (significant at p<0.001) were found among all three tests. Interpretation We provide preliminary evidence of construct validity in the Strength–Dexterity Test. Our findings suggest that this test has the potential to be developed into a promising tool for assessing dexterity in children.