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The literature abounds in analyses of the causes, diagnosis and treatment schemes for handling dental-facial asymmetries. In the course of time, however, our understanding of the subject has improved considerably, thanks to efforts and findings contributed by different researchers.

As suggested in the first article of this series, much of what we know, or believe to know, about growth of the craniofacial skeleton, is but an oversimplification and an underestimation of the real nature of this extremely complex phenomenom. This second part is a brief compendium of research and principles on which the previous paper is based. Information included is partly the result of several years of research, as well as some notions of a speculative nature. In both cases, emphasis centers on the type of information deemed necessary if we pretend some day to understand fully why the face grows as it does. Additionally, some forms are proposed to prove ideas which aim to explain craniofacial growth. The main objective of this article is to provide elements that may allow us to understand the interrelation between structure and function in craniofacial anatomy, thereby establishing the bases of "functional symmetry" as a promising attempt to provide new elements leading to a better understanding of craniofacial biology.

ACC-9653, a prodrug of phenytoin synthesized to be water soluble, is converted to phenytoin by phosphatases. In this study, 43 patients received ACC-9653 IV or IM. Side effects were transient and minor. The conversion half-lives of ACC-9653 after intravenous and intramuscular administration averaged 8.4 and 32.7 minutes, respectively. Peak phenytoin concentrations occurred 42 minutes after IV and 151 minutes after IM administration.

A controlled study was designed to clarify the indications for antibiotic therapy in children with advanced cystic fibrosis hospitalized with respiratory exacerbations. Twenty-two children with severe CF and signs of acute lower respiratory infection were randomly assigned to receive either cloxacillin or carbenicillin plus gentamicin administered intravenously for ten days. Other aspects of therapy were constant. The groups were comparable in all respects and Pseudomonas aeruginosa was the predominant sputum pathogen in most patients. Clinical improvement, chest radiograph changes, evidence of airway obstruction, and bacteriologic flora of sputum were no different regardless of the regimen used. These results suggest that the use of anti-Pseudomonas medication in these children may not always be necessary. These observations need to be confirmed by blind-controlled studies in larger numbers of patients with mild as well as severe respiratory involvement.

Well-controlled prospective studies have shown the benefits of converting treatment for patients with epilepsy from polytherapy to monotherapy. Results of trials with valproate have demonstrated its efficacy as monotherapy in patients with generalized tonic-clonic seizures. Several studies have found no significant differences between valproate and phenytoin and carbamazepine in the treatment of partial seizures. In studies in which patients were diagnosed as having one of the primary generalized epilepsies, the response rate of tonic-clonic seizures to valproate establishes valproate as the drug of choice in the epilepsy syndromes with primary generalized tonic-clonic seizures.

Nuclear magnetic resonance (NMR) proton density images of the human brain have been made by the FONAR method. Spin-lattice relaxation times, T1, of water hydrogen protons have been determined at random positions within frontal and temporal regions of the human brain. The primary purpose of this ongoing research is to accumulate a large data base of normal T1 values for water protons in normal human brain tissue. Our experience to date includes 31 measurements on 18 volunteer subjects, and the mean value +/- standard deviation is 215 +/- 42 msec. In addition, two metastatic lesions of the brain were studied and found to have T1 values longer than those for normal brain tissue.

A 44-year-old right-handed man was hospitalized because of a subarachnoid hemorrhage. He was drowsy on admission and exhibited a left partial third nerve palsy, right hemiparesis, and selective motor aphasia. A large subcortical arteriovenous malformation involving the left frontal lobe was demonstrated by angiography. The malformation filled from either carotid system and from the vertebrobasilar system as well. In addition, there were two bilaterally symmetrical (mirror) aneurysms of each internal carotid artery. Computed axial tomography revealed a left intratemporal-intraventricular hematoma. Deterioration of the patient's clinical condition occurred a few days after admission. Improvement was obtained after removal of the hematoma at a left subtemporal craniectomy, at which time the ruptured aneurysm arising from the left internal carotid artery was clipped. Sixteen months later, the intact aneurysm of the right internal carotid artery was clipped, and the arteriovenous malformation was radically excised through a bifrontal (Pool) craniotomy with microsurgical technique and with the aid of intraoperative angiography. The patient remained with a fixed neurological deficit, as observed preoperatively.

Between January 1984 and December 1987 a total of 178 AIDS cases were reported to the Colombian Ministry of Health. The location of these cases suggests that the human immunodeficiency virus (HIV) is widely distributed in Colombia. Most of those afflicted (97%) have been adult males. HIV seroprevalence studies of selected population groups revealed the highest antibody prevalence (5.65% in females, 22.5% in males) among individuals involved in high-risk behaviors who participated in a free AIDS testing program. High prevalences (from 0.6% to 3.9% in females, and 14.6% to 15.9% in males) were also found in patients (primarily female prostitutes and male homosexuals) attending clinics for sexually transmitted diseases in several urban areas. The number of AIDS cases in Colombia has doubled or tripled annually since reporting began in 1984, a pattern similar to that observed worldwide.

Clinical and computerized tomography findings in patients with miliary infestation of cysticerci in brain parenchyma are presented. Cysticercotic encephalitis produces a severe and frequently fatal neurological disorder. Although parenchymal cysticercosis is common in endemic areas, in the cases reported here, the pathology is induced by a severe inflammatory response in brain parenchyma rather than by the physical presence of multiple cysts. As a result of diffuse brain edema, all cases develop subacute severe intracranial hypertension and compromise of visual function. One important feature of this form of neurocysticercosis is that it particularly affects young women.

Two new cases of extradural hematoma associated with traumatic middle meningeal artery pseudoaneurysm are presented. Sixteen such cases have previously been reported in the literature. A 22-year-old man and a 17-year-old woman each developed marked neurological deficits after head injury. In each case percutaneous common carotid angiography demonstrated a conspicuous aneurysmatic sac on the middle meningeal artery, as well as displacement of major intracranial vessels and a surrounding avascular area. At operation the extradural clot was removed and the middle meningeal artery sac was verified. Both patients recovered uneventfully. Histological analysis of one of the specimens was performed.

Twenty-nine subjects trained for 6 weeks for the purpose of comparing the effects of various durations of exercise. All subjects trained three days per week at 75% of maximum heart rate. Training durations were 5 min (N = 10), 15 min (N = 10) and 25 min (N = 9) with over 80% of the training sessions consisting of monitored treadmill walking on a grade. Pre and post-testing consisted of a maximal treadmill walk and a submaximal bicycle ride for the three training groups and a control group (N = 10). The improvements in treadmill time were 7.7%, 14.7% and 20.2% for the three training groups, all significant. The improvement for the 5 min group was not different than that of the control or 15 min groups. Improvement in the 25 min group was significantly greater than the control and 5 min groups, but not the 15 min group. The same differences were noted when estimated maximal oxygen uptake changes were analyzed. The results indicate that at least 15 and preferably 25 min of exercise is necessary to produce optimal endurance improvement with the training intensity and frequency used in this study.

The currently available phenytoin (PHT) solution has many disadvantages stemming from poor aqueous solubility of PHT. A novel approach to solve the problem has been the synthesis of a phosphate ester of PHT (PHT prodrug ACC-9653). This water-soluble compound is metabolized rapidly into PO4 and PHT. A four center open-label, baseline-controlled study of 43 patients with epilepsy maintained on oral twice-daily PHT monotherapy was performed to evaluate the safety and pharmacokinetic profile of the prodrug. Patients received an i.v. or i.m. dose of ACC-9653 at a dose equivalent to the patients' morning dose of PHT. Intravenous dosages were infused at a rate of 75 mg/min, and i.m. dosages were given as one or two injections. After a period of 6 days, during which patients were again maintained with oral PHT, they were given a dose of ACC-9653 via whichever route they had not yet received. The Tmax of the prodrug averaged 5.7 and 36 min (0.095 and 0.606 h) after i.v. and i.m. administrations, respectively. The elimination half-life of ACC-9653 (conversion from prodrug to PHT) after i.v. and i.m. administration was 8.4 and 32.7 min (0.140 and 0.545 h), respectively, and both were independent of the dose. The plasma clearance of ACC-9653 was not dependent on dose or route of administration and averaged 19.8 +/- 1.16 and 17.8 +/- 0.83 L/h after i.v. and i.m. administrations, respectively. The area under curve ratio of PHT after i.m. and i.v. ACC-9653 was 1.17 +/- 0.13 which was not significantly different from 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacillus anthracis is an uncommon cause of meniningitis. The characteristic hemorrhagic features in two patients who died despite antibiotic treatment are presented and discussed.

Carbamazepine and phenytoin are drugs of choice in initial monotherapy for adult partial and secondarily generalized tonic-clonic seizures. These designations reflect the results of the Veterans Administration Epilepsy Cooperative Study Group of 1985. An earlier comparative study of carbamazepine and phenytoin by Ramsay and associates found both drugs equally effective in controlling new-onset seizures. Among the advantages of carbamazepine is that it causes relatively few cognitive and dysmorphic side effects. Its disadvantages are its unavailability in parenteral formulation and its metabolic autoinduction. The latter must be compensated for by planned dosage increases to maintain therapeutic plasma steady-state levels during the first 2 or 3 months of treatment. Carbamazepine is judged a drug of choice in the treatment of these secondarily generalized tonic-clonic seizures, and the drug of choice in children, adolescents, and women susceptible to the dysmorphic side effects associated with other anticonvulsant agents.

Two patients with the diagnosis of brain death were evaluated with computerized axial tomography (CAT). After intravenous infusion of 30% Conray there was no visualization of the intracranial vasculature (circle of Willis). The second patient also had an isoelectric EEG. A third patient with an intracerebral lesion similar to the other cases but without diagnosis of brain death, showed good visualization of the circle of Willis. Therefore, contrast-enhanced CAT scans can be used as another diagnostic aid to confirm brain death.

Measurements were made before and following 3 to 6 months of exercise therapy in 24 patients who had had myocardial infarction (group MI), in 16 patients having positive test and/or multiple risk factors for coronary heart disease (Group CHD), and in 10 patients who had undergone coronary artery bypass surgery (Group CAB). All patients were men and had a mean age of 51.6 years. Exercise training was conducted 3 times per week for a duration of 20 to 40 minutes per session. Walking and jogging both on a treadmill and a track and stationary cycling were used as training modalities. A paired t test was used to determine significance of differences between pre- and post-treatment results for each group. Percent body fat decreased in each group and aerobic capacity increased significantly (p less than 0.01) in all 3 groups (6.2 ml/kg . min-1 in MI, 7.0 ml/kg . min-1) in CHD, and 8.0 ml/kg . min-1 in CAB). Changes in other exercise related variables were found not to be statistically significant. Analysis of variance yielded no difference among the 3 groups for any of the variables evaluated. The results clearly indicate that the trainability of the MI patient is equivalent to that of the cardiac patient who has not suffered an infarct and to that of the post-CAB patient.