Management of pediatric mandibular fractures

The incidence of mandibular fractures is rare in the pediatric population when compared to adults. Although the basic principles for management are the same as for the adult, certain anatomical features of the pediatric mandible warrant special attention. Problems such as mixed dentition, unerupted teeth, and ongoing growth in the mandible require careful diagnosis and planning in deciding on the proper treatment.

Heerfordt syndrome: a cause of facial paralysis

Heerfordt syndrome is an unusual manifestation of systemic sarcoidosis and is characterized by parotitis, uveitis, and facial nerve paralysis. A case is presented and the clinical manifestations are discussed. Angiotensin converting enzyme assays along with tissue biopsy demonstrating noncaseating granulomas confirm the diagnosis.

Caustic ingestion

Caustic ingestion is a serious medical problem affecting anywhere from 5,000 to 15,000 persons per year. The factors influencing the type and seriousness of the burn are numerous. Correct diagnosis using endoscopic technique is imperative in choosing the proper treatment whether it be medical or surgical. Stricture is the most common complication with rates from 2% to 4%.

Frontal sinus fractures: diagnosis and management

The major cause of frontal sinus fracture today is a traumatic episode of considerable force, most commonly, contact of the head with the dashboard or steering wheel in a motor vehicle accident. Computerized tomography is often essential in categorizing the extent of the fracture and defining the method of therapy. In this article, we address a logical approach to assessment and treatment of frontal sinus fractures.

Deletion analysis of the maize mitochondrial superoxide dismutase transit peptide

The maize mitochondrial superoxide dismutase (SOD; EC 1.15.1.1), a nuclear gene product, has been previously shown to be imported into maize mitochondria. The cDNA for maize mitochondrial SOD was subcloned into a vector containing the T7 promoter. Deletions were made in the transit peptide coding region of the cDNA. The undeleted and deleted proteins were synthetically produced by transcription and translation in vitro. Undeleted preSOD-3 is translocated into isolated maize mitochondria with an efficiency of approximately 30%. Mature SOD-3 subunits are recovered from the matrix but not the membranes of subfractionated mitochondria. These subunits are assembled into the tetrameric holoenzyme. The modified SOD-3 precursors are imported into mitochondria at lower efficiencies than undeleted preSOD-3. The relative import efficiency appears to be dependent upon the deletion size. To our knowledge such analysis of a plant mitochondrial precursor protein has not been reported previously.

Tonsil cancer

Tonsillar region carcinoma ranks as the second most common malignancy of the upper aerodigestive tract. Tobacco and alcohol use are the most important risk factors. The rate of cervical metastasis may be as high as 70%. Treatment options include surgery, radiation, chemotherapy, or any combination of these modalities. Overall survival is in the range of 50%.

Control of severe pain with sustained-release morphine tablets v. oral morphine solution

Recently a sustained-release morphine sulfate tablet (MS Contin [MSC]) was introduced in Canada. In a randomized double-blind crossover trial we compared MSC given every 12 hours with a morphine sulfate solution (MSS) given every 4 hours to 17 patients suffering from chronic severe pain. After titration of the morphine dosage to optimize the analgesic effect, each patient received 10 days of therapy with either MSC or MSS, then 10 days of therapy with an equal daily dose of the other formulation. Both preparations provided effective pain control, with minimal side effects. There was no significant difference between MSC and MSS in pain scores on a visual analogue scale (VAS), severity scores for tiredness and nausea, amount of supplemental morphine needed for break-through pain or patient preference. The plasma morphine concentrations tended to be greater during treatment with MSC. The study had an 89% probability of detecting a clinically significant difference in VAS pain scores. We conclude that an individualized, twice-daily regimen of MSC is as effective as MSS given every 4 hours for control of severe pain. The twice-daily regimen has several advantages: it provides for an uninterrupted night's sleep, it is substantially more convenient than the six doses per day required with MSS, and it should help reduce both medication errors and noncompliance.

Anthropometric comparison of cyclists from different events

An anthropometric analysis was conducted upon 36 competitive male cyclists (mean age 23.4 years) who had been competing on average for 8.2 years. Cyclists were allocated to one of four groups; sprint, pursuit, road and time trial according to their competitive strengths. The sample included cyclists who were classified as category 1, 2, 3 or professional (British Cycling Federation and Professional Cycling Association). The sprint cyclists were significantly shorter and more mesomorphic than the other three groups (p less than 0.05). The time trialists were the tallest, most ectomorphic group, having the longest legs (p less than 0.01), the highest leg length/height ratio (p less than 0.05) and the greatest bitrochanteric width (p less than 0.05). The pursuit and road cyclists were found to have similar physiques, which were located between those of the sprinters and time trialists. The biomechanical implications of these differences in physique may be related to the high rate of pedal revolutions required by sprinters and the higher gear ratios used by time trialists.

Mucormycosis of the head and neck

Rhinocerebral mucormycosis is an uncommon but devastating infection of the head and neck. The fungus most commonly affects diabetics who are in ketoacidosis, but can affect other immunosuppressed individuals such as leukemics, burn patients, and patients with chronic renal failure. The pathogenicity of the organism is characterized by a ketone reductase system and its ability to invade arterial blood vessels. Treatment is directed towards correction of the underlying disorder, surgical debridement, intravenous antifungal agents, and possibly a new adjuvant, hyperbaric oxygen. A detailed review of this disease process is provided, along with the recent advances and successes in treating rhinocerebral mucormycosis.

Isolation and characterization of a cDNA for mitochondrial manganese superoxide dismutase (SOD-3) of maize and its relation to other manganese superoxide dismutases

We describe the isolation of a cDNA clone for the nuclear-encoded manganese superoxide dismutase (SOD-3) of maize mitochondria. The cDNA, pSod3.1c, selects by hybridization an RNA which produces the SOD-3 precursor upon in vitro translation. The DNA sequence of pSod3.1c was determined from fragments subcloned in M13. The amino-acid sequence deduced from the nucleotide sequence displays significant homology with the amino-acid sequences of prokaryotic and eukaryotic Mn-SODs, but displays greater homology with mammalian Mn-SOD than it does with yeast or bacterial Mn-SOD. A 31 amino-acid transit peptide also is encoded by the pSod3.1c clone. Analysis of poly(A)+ RNA indicates that Sod3 mRNA is approx. 1250 nucleotides in length. The amount of Sod3 transcript in seedling leaves is increased by light.

Determination of clindamycin in plasma or serum by high-performance liquid chromatography with ultraviolet detection

A simple, sensitive high-performance liquid chromatographic assay for the determination of clindamycin in human plasma or serum has long been hampered by inability to separate it from endogenous compounds. We describe here such an assay. Proteins from a 200-microliters sample were precipitated by addition of acetonitrile containing the internal standard, triazolam. The sample was then vortex-mixed and centrifuged at approximately 3000 g for 10 min. The supernatant was evaporated to about 250 microliters under nitrogen, and 10-30 microliters were analyzed using an autoinjector. An octadecylsilane column with acetonitrile-water-phosphoric acid-tetramethylammonium chloride as mobile phase and ultraviolet detection at 198 nm provided a reproducibly quantifiable peak corresponding to 0.17 micrograms/ml. Retention times for clindamycin and triazolam averaged 8 and 11.8 min, respectively. Replicate standard curves run over a 36-h period showed no loss of integrity; r2 values generally exceeded 0.999. The method has successfully been applied to the analysis of samples taken up to 12 h after administration of intravenous infusions of 600-1200 mg in healthy volunteers.

Dietary regimen and performance of high intensity ergometer exercise

The influence of preceding diet (mixed, MD; carbohydrate CD; protein PD) on performance during high intensity endurance cycling was examined in six middle distance runners. Subjects undertook cycle ergometer exercise at a workload equivalent to 80% VO2 max until exhaustion following each of the three dietary regimens. Dietary analyses were performed using a computerised evaluation technique and cardiorespiratory, blood glucose and lactate responses to exercise were measured along with exercise time to exhaustion. Significant differences in carbohydrate and protein intakes were noted between respective diets as well as significantly higher total energy intake in MD (P less than 0.05). A significant relationship was observed between carbohydrate intake and exercise time to exhaustion (r = 0.59, P less than 0.05). No significant differences were noted in cardiorespiratory measures or blood glucose response after exhaustive exercise between the three dietary regimens but peak blood lactate concentration was lower following PD (P less than 0.05). Total time to exhaustion was significantly higher on CD (1070.0 +/- 106.7 s) than on PD (642.5 +/- 84.3 s, P less than 0.01). Performance time on MD (895.7 +/- 84.3 s) did not differ significantly for performance time on either CD or PD. It was concluded that dietary manipulation significantly improves exercise time to exhaustion during short term, high intensity cycling.

Atrophy of the stria vascularis as a cause of sensorineural hearing loss

Correlations were made between pure-tone thresholds and computer-aided cross-sectional measurements of the stria vascularis on histological sections of postmortem cochleas from 24 subjects who had reliable audiometric records. The criterion for selection was strial atrophy as the predominant pathological change in 17 experimental ears and normal hearing for seven control ears. Losses in the summed cross-sectional areas of stria vascularis showed a direct correlation with hearing loss. The cause for the strial atrophy is presumed to be a genetically determined predisposition for early cellular decay. The mechanism by which strial atrophy causes hearing loss is speculative.

In vitro synthesis, importation and processing of Mn-superoxide dismutase (SOD-3) into maize mitochondria

In vitro translation of maize scutellar polysome-bound RNA and poly(A)+RNA produces a precursor for the mitochondrial superoxide dismutase (SOD-3) of maize, which can be immunoprecipitated with SOD-3 monospecific antibodies. The precursor SOD-3 (preSOD-3) has both a greater molecular weight and a more positive isoelectric point than the mature (purified) SOD-3. These differences were not observed for the cytosolic isozyme (SOD-4) which was similarly synthesized and isolated. PreSOD-3 specifically associates with maize mitochondria when incubated in vitro, whereas SOD-4 does not. The ionophore valinomycin (at concentrations of over 1 microM) inhibits the uptake of preSOD-3 into mitochondria. The integrity of the mitochondrial preparations was determined by assay of oxygen consumption, citrate synthase, and cytochrome-c oxidase activity.

Pick's disease. Clinical genetics and natural history

The relatives of 18 probands with neuropathologic evidence of Pick's disease were assessed with the main aim of estimating their risk for dementing illness. Fifteen secondary cases of dementia were discovered among relatives. The risks were significantly greater for probands' first-degree relatives than for second-degree relatives, which suggests an etiologic contribution from genes. Although numbers are small, the distribution of cases and their ages at onset are consistent in suggesting a sex effect, with male subjects more at risk than female subjects.

Cloning of cDNA for maize superoxide dismutase 2 (SOD2)

A cDNA clone encoding maize cytosolic superoxide dismutase 2 (SOD2) was isolated from a cDNA library constructed in pUC9 plasmids from size-selected poly(A)+ RNA. The library was screened with mixed synthetic oligode-oxynucleotide probes. The sequence of the probes was derived from the amino acid sequence from a region of the protein near the NH2 terminus. One positive clone contained an insertion of a 612-base-pair fragment. The amino acid sequence, deduced from the nucleotide sequence of the cDNA, revealed that the clone contained the coding region for all but the first of the 151 amino acids of the SOD2 protein. Additional 5' and 3' flanking sequences, absent on the pUC9 Sod2 clone, were obtained from a lambda gt11 clone isolated from a maize leaf library probed with the pUC9 Sod2 insert. Hybrid-selection translation assays also demonstrate that the cDNA clone contains Sod2 sequences.

Assessment of the power performance of racing cyclists

A 30-s 'all-out' power protocol was studied in four groups of racing cyclists including internationals (n = 8), Category 1 (n = 10), Category 2 (n = 15) and Category 3 (n = 11). Following warm-up each subject completed five trials interspersed by 3 min of low intensity exercise on an ergowheel racing cycle ergometry system at a power output of 15 W kg-1 body weight, generated at 130 rev min-1. Temporal indices of performance included delay time (DT) to achieve the power criterion, total time (TT) of the maintenance of the power criterion and the ratio of TT/DT. 'Explosive' leg strength was assessed from a vertical jump. The results indicated that international and Category 1 cyclists had lower DT (2.2 +/- 0.1 s and 2.1 +/- 0.0 s, respectively; P less than 0.05), higher TT (28.1 +/- 0.7 s and 27.0 +/- 0.7 s, respectively; P less than 0.05) and elevated TT/DT (12.8 and 12.9, respectively; P less than 0.01). 'Explosive' leg strength was also higher (P less than 0.05) in the internationals than in the other groups of cyclists. The protocol provides a sport-related method for the assessment of short term endurance performance ability in racing cyclists which may be of value in identifying the anaerobic capability of individual cyclists.

Injury prediction in female gymnasts

In order to identify injury-proneness in female competitive gymnasts, 20 measures of flexibility, hypermobility, spinal posture and anthropometry were performed on 40 competitive gymnasts and injury scores were derived from the severity and extent of previous gymnastic injury and inherent hypermobility traits. Results were compared between contrasting groups of "low" and "high" injury gymnasts respectively (both N = 10). Nine variables demonstrated significant differences between the "low" and "high" injury risk status groups namely, weight (p less than 0.001), height (p less than 0.001), age (p less than 0.001), mesomorphy (p less than 0.01), Quetelet Index (p less than 0.01), shoulder flexion (p less than 0.05) and lumbar extension (p less than 0.05), standing lumbar curvature and total peripheral flexibility score (both p less than or equal to 0.05). Multiple regression analysis was applied to determine the relative contribution of these variables to the estimation of injury-proneness as evidenced by previous history of injury and hypermobility traits. Using 9 independent variables, multiple regression yielded a multiple correlation coefficient (R) = 0.840, accounting for over 70% of the observed variance (R2 = 0.706) in injury scores among the total group of gymnasts. However, a subset of five variables, (weight, mesomorphy, standing lumbar curvature, age and height) yielded a multiple correlation coefficient (R) = 0.834 accounting for almost 70% of the observed variance (R2 = 0.696). This was not significantly different from the larger subset. Using injury classification system of "low", "medium", and "high" risk categories, comparisons were made between predicted and observed injury scores in the respective risk categories. In "high" risk and "low" risk gymnasts, injury scores could be classified correctly with 70% and 79% accuracy respectively, so that relative risk status could be determined from simple physical tests which may be employed by practitioners in the field.

Fertility and parental age in Alzheimer disease

The association of Alzheimer Disease (AD) with reduced fertility and increased parental age at time of birth were investigated in a sample of 126 individuals with AD. Relative to their normal siblings, maternal age at time of birth of the ADs was not significantly increased, nor were the AD individuals more likely to be later-borns in their sibships. The percentage of individuals bearing children was 75.7% for AD versus 70.8% for their normal siblings. For those ever bearing children, ADs produced slightly more children than their normal siblings (average of 3.92 versus 3.67). It was concluded that AD is not associated with either reduced fertility or increased parental age.

Ergogenic demands of a 24 hour cycling event

The maximal aerobic performance (VO2 max) and energy costs of cycling at various power outputs and equivalent road speeds of a highly trained endurance cyclist (age 23.4 yrs, height 1.95 m, weight 73.1 kg), were measured in the laboratory on an eddy-current cycle ergometer, and the physiological responses related to determinations made during a 24 h cycling time trial event, using continuous ECG recording from which estimates of ergogenic demands were obtained. The cyclist covered a distance of 694 km during the event at an average speed of 28.9 km.h-1 which corresponded to an equivalent oxygen cost of 38.5 ml.kg-1 min-1 and represented approximately 55% of his VO2 max. During the event, the cyclist expended an estimated 82,680 kJ of energy, of which approximately 44,278 kJ (54%) were supplied by repeated feedings of liquids, solids and semi-solids and some 38,402 kJ (46%) came from the stored energy reserves which resulted in a 1.19 kg loss of body weight during the event. The energy demands of the activity were more than three times greater than the highest recorded values of severe industrial work, and similar to the hourly rates of expenditure of shorter duration competitive events, but above the highest values reported over other extreme endurance events over the same period of time. The results thus represent near maximal levels of sustainable ergogenic effort by man over a complete 24 h cycle.

The carbohydrate maintenance properties of an experimental sports drink

The effects of an experimental sports drink (Q) were compared with a commercial sports drink (D) of proven ergogenic efficacy. Seven highly trained subjects performed two hours of cycle ergometry exercise at approximately 65% maximal aerobic power (VO2 max) while receiving levels of Q and D in quantities designed to supply approximately 28% of the total energy requirement of the exercise task. Both Q and D formulations were supplied at 15 minute intervals at 16 degrees C, in volumes required to provide equivalent carbohydrate loads from two products of differing concentrations and compositions. Q was equally as effective as D in terms of the maintenance of plasma glucose concentrations during exercise, while selected physiological indices of work performance favoured Q. However, the time course of plasma glucose concentration changes during and after exercise indicated a trend towards more rapid uptake and assimilation of carbohydrate in the case of Q. The findings suggest that Q may provide a more readily available carbohydrate source during exercise and may enhance work performance through its ergogenic properties.

Comparative teratogenic effects of methyl salicylate applied orally or topically to hamsters

Methyl salicylate was administered topically to pregnant hamsters at 7d9h and the teratogenic results were compared with those obtained following oral treatment with the same compound. Both treatments produced the same defect in embryos recovered at day 9: failure of fusion of the neural tube, especially in the area of the developing brain. Analysis of serum salicylate levels following both treatments produced similar curves and indicated that teratogenic levels of salicylate can reach the maternal circulation after topical exposure.

Gastrocolic fistula complicating benign gastric ulcer. A case report and review of the literature

Gastrocolic fistula complicating gastric or colonic surgery is a well-recognized entity. It is extremely rare, however, to encounter this condition in patients with benign peptic ulceration who have not undergone previous abdominal surgery. Such a patient was seen recently at Addington Hospital, Durban. The diagnosis was confirmed by means of barium enema examination and subsequent successful surgical resection of the fistula was performed.

Seasonal changes in cyclists' performance. Part I. The British Olympic road race squad

British Olympic road squad cyclists were monitored during the 1980 racing season to evaluate training for the Moscow Games. Riders demonstrated reductions in body fat index, % body fat and endomorphy (p greater than .05). Graded exercise, using a "Racermate" wind load simulator/racing cycle ergometer system, showed reduced cardiovascular demands to warm-up exercise, and increased cardiovascular index, VO2 maximum, aerobic/anaerobic threshold shifts during maximal exercise (NS), with no changes in gearing, equivalent road speed, absolute/relative power output and leg power. Compared with "non-select" riders demonstrated lower body fat index, % body fat and endomorphy (p greater than .05), higher Hb and PCV % (p greater than .05) and elevated neuroticism and extraversion (p greater than .05). Furthermore, "select" riders demonstrated lower HR and CV index during warm-up exercise (p greater than .05), and elevated CV index, VO2 maximum, aerobic/anerobic thresholds during maximal exercise (p greater than .05), resulting from higher gearing, equivalent road speed and absolute/relative power output (p greater than .05).

Seasonal changes in cyclists' performance. Part II. The British Olympic track squad

In Part II of the study, the British Olympic track (sprint) squad cyclists demonstrated reductions in body fat index, % body fat and endomorphy (p greater than .05), increased Hb and PCV % (p greater than .05), and lowered HR at rest and in warm-up exercise (p greater than .05), but no change in leg power. Repeated interval sprints of short duration, maximal exercise on an "ergowheel" ergometer, at standardised power output, showed increased anaerobic index (p greater than .05) and acceleratory power (p greater than .01) but no change in sustained power output. Compared with "non-select" riders, a case study of the single "select" rider showed anthropometric differences in terms of lower height, weight, body fat index, % body fat and endomorphy, but enhanced mesomorphy and FEV %. Furthermore, the "select" rider demonstrated temporarily latent functional performance capabilities, in that increased anaerobic index, acceleratory and sustained power indices, as well as enhanced relative power output, were not identified until late in the competitive season.

A controlled comparison of joint reactions among women receiving one of two rubella vaccines

While transient rheumatic side-effects are not uncommon in women receiving any of the attenuated rubella virus vaccines yet developed, few comparative data are available on the only rubella vaccine currently available in the United States - the RA 27/3 vaccine. In this study, the frequency and severity of joint reactions were compared among seronegative women receiving HPV77DE5 vaccine (n = 59) or RA 27/3 vaccine (n = 53), and in seropositive vaccinees receiving either vaccine (n = 60). The proportions of vaccinees developing arthralgia/arthritis were similar (29 per cent and 26 per cent, respectively) in the seronegative groups, and were significantly higher than in the seropositive control group (3%). The onset of symptoms was earlier and their duration was briefer in those receiving RA 27/3 vaccine compared to the HPV77DE5 vaccine recipients. No chronic or recurrent symptoms were observed. These data, along with previous studies, suggest that while transient rheumatic reactions following rubella vaccination are not uncommon, they are not associated with serious disability and should not interfere with ongoing immunization programs.

Clinical features of twig snake (Thelotornis capensis) envenomation

A case of disseminated intravascular coagulation in a 13-year-old-boy caused by a bite from a twig snake (Thelatornis kirtlandii capensis) is described. The coagulant enzyme was found to be a single-chain mole-activate prothrombin and factor X as well as weakly accelerating fibrinolysis. Its action on synthetic chromogenic substrates is described. Boomslang antivenom was unable to block twig snake venom, and the implications of this as regards treatment are discussed.

Late obstruction of the intrahepatic common bile duct after seat-belt injury

A patient is reported in whom obstructive jaundice developed 10 weeks after seat-belt injury to the abdomen. Laparotomy at the time of injury revealed extensive lacerations of the liver and haematoma in the head of the pancreas. The patient's presentation with jaundice led to a diagnosis of an intrahepatic haematoma, falsely substantiated by radio-isotope studies. At operation, complete obstruction of the intrapancreatic portion of the common bile duct was found. This, most likely a result of vascular damage with subsequent cicatrization, was treated satisfactorily by choledochoduodenostomy.

An outbreak of rubella among hospital personnel

An outbreak of 47 cases of rubella occurred among hospital personnel in a large medical-surgical hospital. As a result, one pregnancy was terminated and 475 employee workdays were lost. Epidemiologic investigation of the outbreak suggested a common source; a dietary worker was identified as the probable index case. Serum samples of 12 per cent of women employees were negative for rubella antibody at the time of the outbreak. Neither a history of rubella nor a history of immunization with rubella vaccine was reliable in the prediction of the presence or absence of immunity. Two thirds of all hospital personnel were immunized through a voluntary mass-immunization program, but the response of physicians to the program was disappointing. Outbreaks of rubella that occur in hospitals with prenatal clinics are of special concern. Testing of all employees for rubella antibody and immunization of those determined to be seronegative should be considered.

Heritability of cranium bifidum and spina bifida in the golden hamster

The heritability (h2) and frequency of the neural tube closure defects, cranium bifidum (CB) and spina bifida (SB), have been estimated for a population of 9-day-old hamster embryos through half-sibling analysis. The average frequency of the total affected embryos per litter is approximately 17% while the pooled estimate forh2based on between sires and between dams within sires components was 4%. This value points to the importance of environmental factors in contributing to the variance in defect frequencies observed within this population.

Management of blunt pancreatic trauma. A report of 3 cases

Three cases in which the sole injury was a major pancreatic laceration secondary to closed abdominal injury are presented, and the literature on major closed injuries of the pancreas is reviewed. The diagnosis, surgical management and complications of closed injuries of the pancreas are discussed. Delay in diagnosis, inadequate surgery and failure to recognize common complications of pancreatic injury are responsible for the current high mortality rates for this form of closed abdominal trauma.

Serum insulin and glucose response to graded exercise in adults. Part II. The effect of exercise conditioning

The effect of conditioning to severe exercise upon serum immunoreactive insulin levels (IRI) and serum glucose concentrations (GC) was studied in active and sedentary groups of middle-aged men. The responses of serum IRI and serum GC were determined during graded cycle ergometer exercise which required similar low and high relative work intensities, before (pre) and after (post) a four month physical fitness programme. Both groups demonstrated a marked decline in serum IRI during high intensity exercise from pre to post tests, and a tendency to maintain serum, GC (sedentary group) or elevate serum GC (active group) during exercise, following the conditioning programme. The data provides evidence of a bi-directional response of serum IRI and serum GC to graded exercise, with only minor modifications in the response patterns resulting from exercise conditioning.