Pulmonary dysfunction after cerebral injury

Pulmonary dysfunction is a common complication of severe head injury. The degree of initial hypoxemia which develops appears to correspond with the location and magnitude of the head injury. If unrecognized and not aggressively treated, the hypoxic insult will magnify the cerebral insult. A severe postinjury hypermetabolic state also develops and, if unrecognized and not managed aggressively with nutritional support, can also lead to severe catabolism, increased infection, and further lung dysfunction. Although supportive care is the major treatment at present, pharmacologic manipulation of the increased catecholamine activity, which is considered to be causative, may be effective in controlling both the impaired gas exchange and the hypermetabolic state. A knowledge of the various lung dysfunction states which occur in the head-injured patient population is required to optimize recovery and minimize complications.     

The pharmacology of a new pasteurized antihemophilic factor concentrate derived from human blood plasma

The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot.     

Percutaneous umbilical blood sampling and umbilical vein transfusions. Rapid serologic differentiation of fetal blood from maternal blood

Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.     

Short-Term Influence of Lingual Orthodontic Therapy on Microbial Parameters and Periodontal Status: A Preliminary Study

Objective:To perform a preliminary study of the short-term effect of fixed, customized lingual orthodontic appliances on periodontal and microbial parameters.Materials and Methods:The sample comprised 20 subjects (6 males and 14 females) with a mean age of 22.3 years ± 8.6 years. Before (T₀) and 4 weeks after placement (T₁) of custom-made lingual appliances on the lower teeth only, plaque index (PI), probing pocket depth (PPD), and bleeding on probing (BOP) were measured. A 16S rRNA-based polymerase chain reaction (PCR) method was used to detect Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) in the crevicular fluid. To compare periodontal parameters on bonded lingual (testing) and unbonded palatal (control) and labial (control) sites between T₀ and T₁, the Wilcoxon test was applied.Results:On the lingual aspects of bonded teeth, a significant increase of BOP (T₀: 23.4 ± 22.5%; T₁: 46.2 ± 23.5%; P  = .001) and PI (T₀: 0.3 ± 0.3; T₁: 1.0 ± 0.7; P  =  .001) was observed, but no significant changes for PPD (T₀: 2.1 ± 0.4 mm; T₁: 2.2 ± 0.3 mm; P  =  .286) were found. On control sites, no significant changes were recorded for any periodontal parameter. Aa was found in 25% of the patients at baseline (5 subjects) and in 35% of the patients at T₁ (2 additional positive subjects), whereas Pg was found in 5% of the cohort at T₀ and at T₁ (same patient).Conclusions:Even in the short term, insertion of fixed lingual appliances induced a worsening of periodontal parameters restricted to bonded lingual sites.     

Optic disc haemorrhages and vascular abnormalities in a glaucoma population

Purpose: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. Methods: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4–6 months and glaucoma suspects every 1–2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. Results: It was found that during the period under review, 7.4% (n= 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P= 0.0001) followed by 11.4% of primary open-angle glaucoma eyes (P= 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. Conclusions: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance.     

Association of pupillary parasympathetic hyperreflexia and systemic inflammation in patients with systemic lupus erythematosus

In chronic inflammatory diseases, cytokines stimulate the hypothalamus pituitary adrenal axis and the hypothalamus autonomic nervous system (HANS) axis. The present study was performed to find autonomic nervous function parameters in patients with systemic lupus erythematosus (SLE) which are suitable to demonstrate the activation of the HANS axis during systemic inflammation. Thirty-four patients with SLE (age 35.3 +/- 1.9 yr) were investigated by seven standardized autonomic nervous function tests. The SLEDAI and laboratory parameters of systemic inflammation were assessed by standard techniques. Pupillary latency time hyperreflexia was found in 29.4%, whereas maximal pupillary area was hyperresponsive in only 2.9%. A total of 12% had overall cardiovascular autonomic nervous hyperreflexia. Patients with latency time hyperreflexia had more severe systemic inflammation [erythrocyte sedimentation rate (ESR): P < 0.001; C-reactive protein (CRP): P = 0.0094; fibrinogen: P < 0.001; albumin: P = 0.003; antinuclear antibodies: P = 0.020]. The longitudinal study of 13 patients during 4 yr demonstrated a parallel increase and decrease in latency time percentile and ESR. SLE patients with increased systemic inflammation had an activated HANS axis which can be measured by a parasympathetic pupillary reflex test.      

Elevation of serum cystathionine levels in patients with cobalamin and folate deficiency

Homocysteine can be methylated to form methionine by the cobalamin- (Cbl) and folate-dependent enzyme, methionine synthase; serum levels of total homocysteine are elevated in greater than 95% of patients with either Cbl or folate deficiency. Homocysteine can also condense with serine to form cystathionine in a pyridoxal phosphate-dependent reaction catalyzed by cystathionine beta-synthase. Cystathionine is subsequently cleaved to cysteine and alpha-ketobutyrate by the pyridoxal phosphate-dependent enzyme gamma-cystathionase. To assess levels of cystathionine in Cbl and folate deficiency, we developed a new capillary gas chromatographic-mass spectrometric assay and measured cystathionine in the serum of normal subjects and patients with clinically confirmed deficiencies of these vitamins. The normal range for serum cystathionine was 65 to 301 nmol/L (median = 126 nmol/L) for 50 normal blood donors. In 30 patients with clinically confirmed Cbl deficiency, values for cystathionine ranged from 208 nmol/L to 2,920 nmol/L (median = 816 nmol/L) and 26 (87%) had levels above the normal range. In 20 patients with clinically confirmed folate deficiency, cystathionine concentrations ranged from 138 nmol/L to 4,150 nmol/L (median = 1,560 nmol/L) and 19 (95%) had values above the normal range. Five homozygotes for cystathionine beta-synthase deficiency had high values for serum-total homocysteine and low or low-normal values for serum cystathionine that ranged from 30 nmol/L to 114 nmol/L even though they were on treatment with pyridoxine and had partially responded. One patient with a defect in the synthesis of 5-CH3- tetrahydrofolate and five patients with defects in the synthesis of CH3- Cbl had high values for serum-total homocysteine and high values for cystathionine that ranged from 311 nmol/L to 1,500 nmol/L even though they were on treatment with folic acid and Cbl, respectively, and had partially responded. We conclude that levels of cystathionine are evaluated in the serum of most patients with Cbl and folate deficiency and that they are useful in the differential diagnosis of an elevated serum-total homocysteine level.