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R Barnes

Publications and source records attributed to R Barnes.

194 records · Page 11Linked to original sources

Breast milk contamination in Kazakhstan: implications for infant feeding.

To assist the Ministry of Health of Kazakhstan in making infant feeding recommendations, breast milk samples were analyzed for PCDDs/PCDFs, PCBs, chlorinated pesticides, toxic metals, and cesium-137. Sampling sites were selected to provide a profile of representative exposures to possible contaminants; 92 breastmilk samples from 7 sites were analyzed for chlorinated contaminants and 115 samples from 8 sites were analyzed for toxic metals and cesium-137. With three important exceptions, concentrations of chlorinated contaminants and toxic metals were similar to or lower than those in Europe. Cesium-137 was not detected in any samples. The exceptions were localized contamination with the most toxic dioxin congener, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and generalized contamination with beta-hexachlorocyclohexane and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDT). The localized high concentrations of TCDD (range 6.2 to 118.2 pg/g fat) are the highest documented in the world in a population currently of reproductive age. Calculated incremental lifetime excess cancer risk to an infant exposed to these high concentrations of TCDD range from 28 to 82 x 10(-5). Based in part on the results of this study, the Ministry of Health is promoting breast feeding. However, possible adverse developmental effects associated with both prenatal and postnatal (through breast milk) TCDD exposure have not been adequately assessed. Further epidemiologic research is needed to examine these effects in this newly identified high-risk population.

Adolescent↗

Acute elbow injuries in the National Football League.

We performed a retrospective review to evaluate acute medial collateral ligament injuries of the elbow in professional football players from 1991 to 1996 (5 seasons). There were 5 acute medial collateral ligament injuries in 4 players (1 player with bilateral involvement). All injuries occurred with the hand planted on the playing surface while a valgus or hyperextension force was applied to the elbow. There were 2 centers, both involved with long-snapping situations, 1 running back, and 1 quarterback. All elbows had valgus instability on physical examination. Despite this instability, all players were able to function without operative reconstruction of the medial collateral ligament. No evidence of valgus instability was seen at the time of follow-up (average, 3.4 years). Next, we reviewed all acute elbow injuries in the National Football League from the same 5-season period. Ninety-one acute elbow injuries were reviewed. Overall, there were 70 (76.9%) elbow sprains, 16 (17.6%) dislocation/subluxation patterns, 4 (4.4%) fractures, and 1 (1.1%) miscellaneous injury. Review of the acute elbow sprains revealed 39 (55.7%) hyperextension injuries, 14 (20%) medial collateral ligament injuries, 2 (2.9%) lateral collateral ligament sprains, and 15 (21.4%) nonspecific sprains. The epidemiology of the 14 medial collateral ligament injuries was studied in more detail. The 2 most common mechanisms of injury were blocking at the line of scrimmage (50%) and the application of a valgus force with the hand planted on the playing surface (29%). There were 8 linemen, 4 receivers, 1 running back, and 1 quarterback. All injuries were managed with nonoperative treatment. The average time lost was 0.64 games (range, 0 to 4). We report 19 acute medial collateral ligament injuries of the elbow in elite football players, 2 of whom are considered overhead throwing athletes, who were able to function at a competitive level without surgical repair or reconstruction, in contrast to baseball players, in whom the mechanics and demands may differ.

Adult↗

Fractures about the orbit in professional American football players.

A retrospective review was performed of records for players who suffered fractures about the orbit during participation in officially sponsored activities of the National Football League from 1980 to 1997. Clinical information was obtained on 19 of 29 players who sustained orbital fractures. The most common signs and symptoms included decreased visual acuity (74%, 14), decreased eye movement (42%, 8), hyphema (37%, 7), and infraorbital numbness (21%, 4). The mechanisms of injury were a digital poke (74%, 14) and blunt facial trauma (26%, 5). There were significantly more orbital fractures than zygomatic fractures suffered by offensive linemen as compared with all other positions. Fifteen of 19 players were managed with surgical reconstruction; 4 players were treated nonoperatively. The mean time from injury to surgical procedure was 7.7 days (range, 0 to 42). The mean interval to follow-up was 45.6 months (range, 3 to 146). At follow-up examination, eight (53%) of the patients treated surgically still reported diplopia with upper field gaze. Three of the four patients treated nonoperatively were asymptomatic. The mean time lost from games or practice was 25 days (range, 5 to 56). Ultimately, 17 (89%) players with orbital fractures were able to return to full football activities. Two patients were unable to resume their careers because of residual visual impairment.

Adult↗

Turf-toe: an analysis of metatarsophalangeal joint sprains in professional football players.

Metatarsophalangeal joint injuries of the great toe (turf-toe) are receiving increasing attention in the literature because of the prevalence of synthetic surfaces and lighter, more flexible shoes. Eighty active professional football players were evaluated. The mechanism of injury was hyperextension in 85% of the players. Eighty-three percent reported their initial injury on artificial turf (P less than 0.05). Other factors significantly related to the incidence of turf-toe included player age (P less than 0.01), number of years in professional football (P less than 0.01), and range of ankle dorsiflexion (P less than 0.05). Turf-toe injury resulted in significantly decreased range of motion of the first metatarsophalangeal joint (P less than 0.01).

Adult↗

Postexercise increase in nitric oxide in football players with muscle cramps.

Nitric oxide, a free radical inter- and intracellular messenger molecule, is important in exercise physiology. This study tested the hypothesis that serum nitric oxide concentrations change after strenuous exercise with severe generalized muscle cramps. The study group consisted of 77 professional football players in preseason training. All players' concentrations of serum nitrite and of other serum chemicals were determined during their preseason evaluations and compared with the concentrations in 40 serum samples taken from 25 of those same players who required intravenous rehydration for severe generalized muscle cramps after a training session. Player weight and percentage of body fat were significantly higher in players who received intravenous fluids than in players who did not. The serum of players requiring intravenous hydration showed evidence of skeletal muscle breakdown (increases in lactate dehydrogenase, creatinine phosphokinase, aspartate aminotransferase, and alanine aminotransferase) and of dehydration (elevations in protein, blood urea nitrogen, and cholesterol). The major finding, however, was a nearly 300% increase in serum nitrite concentrations in players requiring rehydration. There were no correlations between concentrations of nitrate and of any of the other serum chemicals. These data support the hypothesis that large amounts of nitric oxide are synthesized in professional football players after strenuous exercise with severe muscle cramps. The study design did not allow us to determine whether this increase in nitric oxide was due to exercise or muscle cramps or both, but it does provide a basis for evaluating these relationships.

Adult↗

Update of guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen.

Guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen were first published by the British Committee for Standards in Haematology in 1996. Key aspects of these guidelines related to anti-infective prophylaxis, immunisation schedules and treatment of proven or suspected infection. A recent review of the guidelines was undertaken, with a view to updating the recommendations where necessary The guideline review process did not reveal any major change in patient groups considered at risk. Occupational exposure to certain pathogens may, however, be a new risk factor for some infections. The recommendations for anti-infective prophylaxis remain unchanged. New recommendations for vaccination include the use of meningococcal group C vaccine in previously non-immunised hyposplenic patients and a need to consider the use of seven-valent pneumococcal vaccine. Recommendations for treatment of suspected or proven infection have not been significantly amended, but a local protocol should take into account relevant resistance patterns. There is an identified urgent need for further research into the effectiveness of varying vaccination strategies in the hyposplenic patient, and audit of infective episodes in this patient group should continue long term. Key guidelines are summarised below, together with grades of recommendation.

Antibiotic Prophylaxis↗