Hypertonic saline solution for control of elevated intracranial pressure in patients with exhausted response to mannitol and barbiturates

Critically elevated intracranial pressure (ICP) represents the most important cause of morbidity and mortality in patients suffering from severe traumatic brain injury (TBI) and is a serious complication after subarachnoid hemorrhage (SAH). Thus new strategies for the control of ICP are required. Based on the evidence available hypertonic saline solution (HSS) may be a promising approach. It was therefore the aim of the present study to evaluate in a prospective manner the effects of HSS on ICP and cerebral perfusion pressure (CPP) in patients with therapy-resistant elevation of ICP. A total of 48 bolus infusions of HSS (7.5%, 2 ml kg-1 b.w.; infusion rate 20 ml min-1) were given intravenously (range 1-15 per patient) to 10 patients (age 41 +/- 6 years) with TBI and SAH. Only patients with ICP > 25 mmHg not responding to standard ICP-management protocol and plasma sodium (Na+) concentration < 150 mmol l-1 were included in the study. Within the first hour after HSS application, ICP decreased from 33 +/- 9 mmHg to 19 +/- 6 mmHg (p < 0.05) and further to 18 +/- 5 mmHg at the time of maximum effect (98 +/- 11 min post bolus). Decrease of ICP was accompanied by a rise of CPP from 68 +/- 11 mmHg to 79 +/- 11 mmHg (p < 0.05) after 1 h and further to 81 +/- 11 mmHg at the time of maximum effect. Plasma Na+ concentration was 141 +/- 6 mmol l-1 before and 143 +/- 5 mmol l-1 1 h after HSS bolus. Corresponding values for plasma osmolality were 302 +/- 11 and 308 +/- 12 mOsm l-1. When the ICP lowering effect was transient, subsequent HSS bolus was necessary 163 +/- 54 min after previous dosing. The present results indicate that repeated bolus application of HSS (7.5% NaCl, 2 ml kg-1 b.w.) is an effective measure to decrease ICP which is otherwise refractory to standard therapeutic approaches. Whether or not the therapy scheme is also suited as primary measure for the control of ICP remains to be established.

FUSCA3 encodes a protein with a conserved VP1/AB13-like B3 domain which is of functional importance for the regulation of seed maturation in Arabidopsis thaliana

Conditionally lethal mutant alleles of the FUSCA3 (FUS3) gene of Arabidopsis thaliana are specifically defective in the gene expression program responsible for seed maturation. FUS3 was isolated by map-based cloning and expression of the FUS3 cDNA resulted in complementation of the Fus3- phenotype. In the predicted FUS3 gene product, a continuous stretch of more than 100 amino acids shows significant sequence similarity to the B3 domains of the polypeptides encoded by ABI3 (Arabidopsis) and VP1 (maize). FUS3 transcription was detected mainly in siliques and was found to be developmentally regulated during embryogenesis. Transcripts of abnormal sizes were observed in fus3 mutants due to aberrant splicing caused by point mutations at intron termini. Sequence analysis of mutant and wild-type FUS3 alleles, as well as sequencing of fus3 cDNAs, revealed small inframe deletions at two different sites of the coding region. While a deletion between B3 and the C-terminus of the predicted polypeptide was found in conjunction with normal FUS3 function, another deletion located within the conserved B3 domain (as well as truncations therein) were associated with the Fus3- phenotype. It is apparent, therefore, that an intact B3 domain is essential for the regulation of seed maturation by FUS3.

Rapid active internal core cooling for induction of moderate hypothermia in head injury by use of an extracorporeal heat exchanger

OBJECTIVE

Moderate hypothermia (32 degrees C) may limit postischemic neuronal damage and is increasingly used clinically in head injury and stroke. For the use of hypothermia as a neuroprotective agent in the prevention of ischemic damage, it is necessary to induce it as soon as possible after the insult and to keep it at the lowest safe level. Active core cooling using an extracorporeal heat exchanger may circumvent the rather slow induction speed and temperature drifts experienced with surface cooling techniques.

METHODS

In eight patients with severe head injuries (Glasgow Coma Scale score, 4-5), a venovenous extracorporeal circulation was established via a percutaneously introduced double-lumen cannula in the femoral vein. A heat exchanger was connected via a pressure-controlled roller pump. In addition to standard parameters, brain white matter temperature was continuously recorded as the target temperature. Cooling was initiated as early as possible with an extracorporeal temperature of 30 degrees C and maintained at a 32 degrees C brain temperature for 48 hours, and then gradual rewarming for 24 hours.

RESULTS

Cooling was able to be initiated within 6 hours and 48 minutes +/- 3 hours and 47 minutes (mean +/- standard deviation) after trauma. A brain temperature of 32 degrees C was reached within 1 hour and 53 minutes +/- 1 hour and 21 minutes after induction of cooling with a cooling speed of 3.5 degrees C per hour. Brain temperature was able to be controlled within 0.1 degrees C intervals, which was especially helpful in gradual rewarming. No cardiac abnormalities or statistically significant changes in coagulation parameters occurred. Mean platelet count decreased to 89,614+/-42,090 on Day 3 after treatment. No clinical bleeding complications or problems resulting from extracorporeal circulation occurred. Moderate hypothermia was a helpful tool for managing increased intracranial pressure; however, five patients of this series died either of their intracranial abnormalities (n = 4) or of a delayed septic shock after pneumonia (n = 1) at various points in time during therapy. The three survivors experienced either an excellent or a good recovery.

CONCLUSION

The results of this investigation suggest that the use of an extracorporeal heat exchanger to achieve active core cooling is suitable for fast and accurately controllable induction, maintenance, and reversal of moderate hypothermia in emergency situations with reliable control of temperature. In this small series of highly selected patients with severe head injuries, we did not note a beneficial effect of hypothermic therapy on outcome.

Remote memory in Parkinson's disease and senile dementia

Remote memory for public events was investigated in 14 demented patients with Parkinson's disease (PD), 14 non-demented PD patients, and 14 controls. These groups were compared with 16 demented patients with dementia that was due to Alzheimer or was of vascular origin (SDAVT), and with a group of elderly controls. The two demented groups were of a different age but displayed a comparable degree of dementia. Remote memory was assessed using a 'famous events' questionnaire with items both of comparable salience and difficulty. Results showed severely impaired retrograde memory functions in the two demented groups for both recall and recognition with non-demented PD patients performing similar to the controls. Remote memory impairments extended 30-40 years without any temporal graded memory losses. Non-demented PD patients and controls showed an inferior free recall performance, especially for the remote past. The two PD groups benefited from recognition to the same extent as the controls, whereas the improvement for SDAVT patients was inferior when compared to their elderly controls. In contrast to SDAVT patients, anterograde memory was associated with remote memory for specific decades in demented PD patients. The results are interpreted with respect to an underlying retrieval deficit with a superimposed anterograde impairment common to both types of dementia and an additional loss of storage sites in SDAVT patients.

Cerebrospinal and plasma amino acid concentrations after administration of i.v. glycyl-glutamine and glycyl-tyrosine containing amino acid solutions in humans

BACKGROUND

Glycyl-glutamine and glycyl-tyrosine may supply adequate glutamine and tyrosine in amino acid solutions for parenteral nutrition. However, plasma peptides may be transported into the cerebrospinal fluid, exerting effects on the neuronal tissue. Cerebrospinal fluid (CSF) and plasma amino acid concentrations after administration of a glycyl-glutamine/glycyltyrosine supplemented amino acid solution were therefore evaluated in a randomized controlled comparison with a conventional amino acid infusion.

METHODS

Dipeptide/amino acid solutions (0.60 mL/h/kg; 82.2 mg total dipeptides/amino acids/h/kg) or conventional amino acid solutions (0.73 mL/h/kg; 83.2 mg total amino acids/h/kg) were infused in 15 patients per group scheduled to undergo spinal anesthesia for urologic surgery over a 12-hour period preoperatively. Plasma amino acids were measured before the infusion was started. CSF and venous concentrations were analyzed simultaneously before the infusion was stopped. CSF samples were drawn through the spinal needle for anesthesia.

RESULTS

The dipeptide-containing solution did not increase either dipeptide to detectable levels in the CSF (detection limit < 5.0 nmol/mL). Venous glycyl-glutamine increased from below detection limits up to 308 +/- 111 nmol/mL (p < .05), whereas glycyl-tyrosine could not be found. In the dipeptide group, venous glutamine and tyrosine were higher (p < .05) but only tyrosine appeared in small amounts (p < .05) in the cerebrospinal fluid.

CONCLUSIONS

This study provides no evidence to support a CSF entry of IV glycyl-tyrosine and glycyl-glutamine under conditions of a normal blood-brain barrier in the adult (detection limit 5 nmol/mL). The data suggest that amino acid solutions containing these dipeptides may be used in parenteral solutions for nutrition support.

Comparison of intermittent and continuous oral administration of calcitriol in dialysis patients: a randomized prospective trial

Intermittent bolus administration of calcitriol--i.e., 1,25-dihydroxycholecalciferol or 1,25-(OH)2D3--is highly efficacious in dialysis patients. In experimental studies, intermittent administration of calcitriol is superior to continuous administration in suppressing preproparathyroid hormone (PTH) mRNA and circulating PTH concentrations. In a randomized, prospective, open multicenter trial 45 dialysis patients with elevated 1,84-iPTH (> or = 20 pmol/l, normal 1-6 pmol/l) levels were randomly allocated to daily administration of 0.75 microgram calcitriol (continuous) or twice weekly administration (intermittent); the two protocols provided an identical total weekly doses of 5.25 micrograms calcitriol. Patients were dialyzed with a dialysate Ca concentration of 1.75 mmol/l and had oral CaCO3 or Ca acetate. 1,84-iPTH (immunoradiometric assay) and serum Ca and Pi levels were measured weekly. At the beginning of the study, the median 1,84-iPTH value was 37 pmol/l (range 20-115) in the intermittent versus 36 pmol/l (range 21-72) in the continuous calcitriol group. After 2 weeks, the median 1,84-iPTH level was 18.5 pmol/l (range 1.4-106) versus 18 pmol/l (range 1.2-48). After 12 weeks, 11 of 21 of the patients in the intermittent and 18 of 24 patients in the continuous group had reached the treatment goal, i.e., 1,84-iPTH < or = 10 pmol/l without hypercalcemia or hyperphosphatemia. There were seven episodes of hypercalcemia (> 2.7 mmol/l) in the intermittent versus two in the continuous group; the mean peak Ca level was 2.8 mmol/l (range 2.76-3.0) versus 2.9 mmol/l (range 2.74-3.06). There were 21 versus 17 episodes, respectively, of hyperphosphatemia (> 2.2 mmol/l).

A reexamination of duplex perception evoked by intensity differences

Duplex perception is a term used to describe the simultaneous evocation of phonetic and nonphonetic percepts, a phenomenon held by some to reveal the operation of a specialized module for phonetic perception. In a widely cited experiment by Whalen and Liberman (1987), duplex percepts were created by replacing the third format transition in a synthetic syllable with a sinusoidal tone glide and manipulating the level of the glide relative to the rest of the syllable. We discuss this study, and report four experiments. The first two made a systematic estimate of the "duplexity threshold"--the tone glide level at which a chirp-like sound could be heard as well as the speech-like syllable. In the third and fourth experiments, we used the results of the first to repeat and extend the experimental procedures in the original Whalen and Liberman study. We discuss the differences in outcome, and conclude that our results may be explained without the need to invoke a specialized phonetic module.

Kinetics of serum 1,84 iPTH after high dose of calcitriol in uremic patients

The temporal relation between oral administration of calcitriol and the nadir of PTH concentration is important for selecting optimal schedules of administration of calcitriol in the treatment of secondary hyperparathyroidism. To further assess this issue we examined 9 patients with preterminal renal failure (3 females, 6 males; median age 58.0 years, range 47-64, median S-Crea 4.8 mg/dl, range 3.7-6.8) with elevated baseline concentrations of 1,84 iPTH (median 46.0 pmol/l, range 18-100). After ingestion of a single oral dose of 2.0 micrograms calcitriol a transient rise in 1,25(OH)2D3 levels was seen with a peak at 6 h (from 20 pg/ml; 14-52 to 43 pg/ml; 35-102). 1,84 iPTH levels did not significantly change in the first 24 h, but were decreased significantly (p 0.01) 48 h after a single oral dose of calcitriol, the time to reach nadir varying from 24 to 96 hours. The percent decrease wa highest in patients with the highest baseline concentrations of 1,84 iPTH. Median 1,84 iPTH levels continued to remain below baseline at 48 h (25.0 pmol/l), 72 h (24.0 pmol/l) and 96 h (24.0 pmol/l) after oral calcitriol. A modest increase of S-Ca was noted which was not statistically significant. We conclude that 1. a single dose of oral calcitriol causes a delayed but long-lasting decrease of 1,84 iPTH, 2. decreased 1,84 iPTH levels persist despite return of calcitriol concentrations to baseline levels and 3. 1,84 iPTH may remain below baseline for more than 96 h.

Identification of toxigenic Vibrio cholerae from the Argentine outbreak by PCR for ctx A1 and ctx A2-B

A polymerase chain reaction (PCR) to detect a region of the A1 cholera toxin gene was applied to the identification of 43 Vibrio cholerae strains isolated from the recent outbreak in Argentina. A good correlation was observed between the GM1-enzyme-linked immunosorbent assay (GM1-ELISA) to detect the B subunit of the enterotoxin and PCR. However, a V. cholerae non-01 strain that was negative by the ELISA test, was positive by the PCR assay for the A1 region. A second PCR test to detect the A2-B coding region was developed to solve this case. We propose that routine detection of toxigenic V. cholerae by PCR should include analysis of A2-B coding region or the whole cholera toxin operon.

[Fever, headache and paralysis of the left leg]

A 17 year old man was hospitalized because of fever, headache and a paresis of his left leg. Radiologic findings demonstrated a subdural interhemispheric empyema on the right side as a complication of ipsilateral pansinusitis. Streptococcus milleri was cultured as the only pathogen from maxillary sinus suppuration. Pathogenesis and therapy of subdural empyema are discussed. Cure was achieved with ceftriaxone, flucloxacilline and ornidazole during one week followed by ceftriaxone as monotherapy during further five weeks. The importance of streptococcus milleri as causing agent of purulent lesions in internal organs is stressed.

Acute mastoiditis: clinical, microbiological, and therapeutic aspects

The charts of 73 children (31 girls, 42 boys) aged 4 months to 14 years (mean 4.5 years) with acute mastoiditis managed during a 16-year period were reviewed. Of the patients 36% were less than 24 months old. Retro-auricular swelling was described in 63 of the 73 children, tenderness in 59, erythema in 58, and protrusion of the auricle in 45. A pathological tympanic membrane was noted in 33% of the patients and fever in only 29%. Apart from local inflammation, the most frequent complaints and symptoms were otalgia (n = 42), recent upper respiratory tract infections (n = 22), and fever alone (n = 22). A subperiosteal abscess was found in 36 patients, and CNS involvement in 5. Nearly half of the patients (48%) were on antibiotic therapy at admission. The isolation rates in bacterial cultures from subperiosteal aspirated (81%) and from mastoid mucosa (68%) were considerably higher than from blood cultures (14%) and were not influenced by previously administered antibiotics. Pneumococci (9/32) and Staphylococcus epidermidis (6/32) were the agents most often isolated. The incidence of the bacteria isolated from patients pre-treated with antibiotics differed from the incidence in patients not previously treated. In 24 patients (33%) the lesion healed with antibiotic therapy without mastoid surgery. Myringotomy and the insertion of a ventilation tube is indicated initially, if acute otitis media with effusion is found. In the absence of a subperiosteal abscess and of CNS involvement, a 48-hour trial of intravenous antibiotic therapy, directed also against staphylococci, is justified before mastoid surgery is considered.

[Clinical comparison of 2 modern rhinomanometers]

Two rhinomanometers (the NR 6 manufactured by Mercury, Scotland and the Rhino-Comp manufactured by Cintec, Sweden) were tested and compared in five subjects. Both instruments are suitable for clinical use and produced equal measurements of nasal airway resistance. The Rhino-Comp device is easier to handle. Technical improvements would be desirable in both machines.

[Normal values in rhinomanometry]

Despite various methods of investigation, there are few reports as to the normal values of nasal airway resistance. A total of 56 adult subjects free of any nasal disease underwent nasal airway resistance measurement using active anterior rhinomanometry according to the guidelines of the international committee on standardization of rhinomanometry. Inspiratory and expiratory resistance was measured before and after application of a topical decongestant spray. This test was reproducible in that 46 of the subjects underwent a second study with resistance values quite close to that of the initial measurement. The upper range of the total inspiratory nasal airway resistance was 0.45 Pa s/cm3 before and 0.3 Pa s/cm3 after decongestant administration. There was no statistically significant difference between the inspiratory and expiratory resistance measurements. No correlation could be made between nasal airway resistance, age, sex, height or weight.

Delayed type hypersensitivity (DTH) in anti-IgM-treated B cell-depleted mice: analysis of induction and effector phase

The induction and the effector phase of murine delayed type hypersensitivity (DTH) were evaluated in mice treated from birth with anti-IgM antibodies; these mice had no mature B cells and could not produce an antibody response. To study the effector phase, long-term cultured cloned helper T cells were injected subcutaneously together with the specific antigen into the hind footpad of normal and B cell-deficient mice. Antigen-specific DTH responses assessed by the local swelling reaction 24 h after transfer measured against a particulate antigen (sheep red blood cells, SRBC) as well as a soluble antigen (ovalbumin, OVA) were unaffected by the absence of B cells. To study the induction phase of DTH, 3-day immune in vivo primed lymphocytes from normal or B cell-depleted mice were adoptively transferred by subcutaneous injection into the hind footpad of naive syngeneic recipients. B cell depletion did not affect the induction of cells capable of responding to SRBC; in contrast, the response to soluble antigen (OVA) was significantly reduced, suggesting that B cells or their products participated in the induction of a DTH response to a soluble antigen.

Mast cell degranulation as a major event in the effector phase of delayed-type hypersensitivity induced by cloned helper T cells

A kinetic study (0-72 h) was performed on the cellular composition of the exudate in delayed-type hypersensitivity (DTH) induced by the injection of cloned helper T cells into the footpad of C57BL/6J mice. In this model the reaction was maximal at 24 h, as assessed by local swelling. After an initial phase of inflammatory cell infiltration, we observed pronounced degranulation of mast cells, occurring at 15-19 h. Administration of antihistamines shortly before this time significantly inhibited the increase in footpad thickness at 24 h, suggesting mast cell mediators as a major cause of swelling in DTH. Furthermore, a new arrival of inflammatory cells, particularly eosinophils, was clearly correlated with mast cell degranulation. The latter, which might function to suppress local reactions, persisted as the only intact cell type after 48 h. Supplementary examination of peripheral blood smears showed successive peaks of neutrophils (at 3 h), monocytes (at 15 h) and finally eosinophils (after 20 h). These results suggest a local and systemic cascade in DTH which depends on mast cell degranulation for its full expression.

Spontaneous cerebrospinal fluid otorrhea

Spontaneous cerebrospinal fluid (CSF) otorrhea is rare. We present four new cases and an analysis of the literature. Two distinct subtypes occur. Seventy-two percent of cases are the childhood type with congenital defects of the otic capsule. Meningitis, usually pneumococcal and frequently recurrent, occurs in 92% of these cases. CSF otorrhea follows myringotomy for a presumed serous effusion. The child usually has unilateral and sometimes bilateral absence of cochlear and vestibular function and commonly exhibits a Mondini deformity. CSF usually enters the inner ear through a dural defect in the lateral aspect of the internal auditory canal and exists through the oval window. Treatment should consist of stapedectomy and packing of the vestibule with muscle or subtotal petrosectomy. Twenty-eight percent of cases of spontaneous CSF otorrhea are the adult type characterized by bony dehiscenses, most commonly of the tegmen tympani or tegmen mastoideum and less commonly of the posterior fossa plate. The meningeal defects are either meningoencephaloceles or simply holes in the dura. Therapy should consist of a mastoidectomy in conjunction with a transtemporal supralabyrinthine (middle fossa) approach if a meningoencephalocele of the tegmen is found.

The pathogenesis of maxillary sinus pneumoceles

Pneumocele is a pathologically expanding, air-containing paranasal sinus most common in the frontal sinus. To our knowledge, only six cases of pneumoceles of the maxillary sinus have been reported so far; to these we add a seventh. The pathogenesis of pneumoceles has not been fully understood. It has been postulated that a one-way valve between the nasal cavity and the affected sinus leads to increased antral pressure and sinus expansion after nose blowing. By monitoring antral pressure through a transoral puncture, we demonstrated a one-way valve between the nose and the maxillary antrum. To our knowledge, this is the first verification of the trap-valve hypothesis.