B Cell Depletion With an Anti-CD20 Antibody Enhances Alloreactive Memory T Cell Responses After Transplantation.

Alloreactive memory T cells mediate accelerated allograft rejection and transplant tolerance resistance. Recent studies have shown that B cell deficient-µMT mice fail to mount donor-specific memory T cell responses after transplantation. At the same time, other studies showed that pretransplant B cell depletion using rituximab (IgG1 anti-CD20 mAb) combined with cyclosporine A promoted the survival of islet allografts in monkeys. In this study, we investigated the effect of anti-CD20 antibody-mediated B cell depletion on the memory T cell alloresponse in mice. Wild-type and anti-OVA TCR transgenic mice were treated with an IgG2a anti-CD20 monoclonal antibody, which depleted nearly all B cells in the peripheral blood and secondary lymphoid organs but spared some B cells in the bone marrow. B cell depletion did not affect the direct alloresponse but resulted in a marked increase of indirect alloresponse after skin transplantation of naïve mice. Furthermore, in allosensitized mice, anti-CD20 mAb treatment enhanced the reactivation of allospecific memory T cells and accelerated second set rejection of skin allografts. This suggests that the effect of anti-CD20 antibodies on alloimmunity and allograft rejection might vary upon the nature of the antibodies as well as the circumstances under which they are delivered.

Morphology of femtosecond laser modification of bulk dielectrics.

Using 3D Finite-Difference-Time-Domain simulations, we study the morphology of the laser-created damage inside fused silica. Among the competing effects limiting the intensity in the dielectric, we find the most important is the pulse defocusing by the plasma lens, partially balanced by the Kerr effect. Less important are collisional energy dissipation and laser depletion by multi-photon absorption. We also found that the profile of generated plasma is asymmetrical in the transverse cross-section, with the plasma extended along the direction perpendicular to the laser polarization.

What should every dental health professional know about electronic cigarettes?

Electronic cigarettes (E-cigarettes) have become increasingly popular around the world. Currently, dental professionals' knowledge and attitudes are varied with many clinicians unclear regarding the impact of E-cigarette products on the oral and general health of their patients. With developing social and health-related challenges, advice of dental and medical associations and other regulatory bodies on E-cigarette use is changing. Growing evidence demonstrating the risks of E-cigarette usage has prompted a review of legislation in the United Kingdom (UK), United States of America (USA), Australia and Canada to include the sale and availability of E-cigarettes, particularly those containing nicotine. Further consideration within the scientific and public health community is being given to assessing demographic usage patterns particularly uptake by non-smokers and adolescents, efficacy as a cessation tool, the impact of vapour on bystanders and direct injuries via explosions as well as emerging lung injuries. This article aims to provide a summary of the most up to date evidence relating to E-cigarette use, the latest position of dental associations and the oral health implications of E-cigarettes compared to conventional smoking. The article also aims to collate this information in order to provide dental clinicians with guidance on how to advise patients, specifically in answering common questions posed regarding E-cigarette use.

Calsensin: a novel calcium-binding protein expressed in a subset of peripheral leech neurons fasciculating in a single axon tract.

The mAb lan3-6 recognizes a cytosolic antigen which is selectively expressed in the growth cones and axons of a small subset of peripheral sensory neurons fasciculating in a single tract common to all hirudinid leeches. We have used this antibody to clone a novel EF-hand calcium-binding protein, calsensin, by screening an expression vector library. A full-length clone of 1.1 kb identified by the antibody was isolated and sequenced. In situ hybridizations with calsensin probes and antibody staining using new polyclonal antisera generated against calsensin sequence demonstrate that calsensin indeed corresponds to the lan3-6 antigen. Calsensin consists of 83 residues with a calculated molecular mass of 9.1 kD that contains two helix-loop-helix domains. The calcium-binding domains are likely to be functional in vivo since a fusion protein derived from the calsensin clone binds 45Ca2+ in vitro. Immunoaffinity purification experiments with the lan3-6 antibody shows that a large 200,000 M(r) protein selectively copurifies with calsensin in two different leech species. These results suggest that calsensin may be functioning as a trigger protein which interacts with the larger protein. These data are consistent with the hypothesis that calsensin may mediate calcium-dependent signal transduction events in the growth cones and axons of this small group of sensory neurons which fasciculate in a single axon tract.

[Microfracture and specific rehabilitation for treating osteoarthritis of the knee. Indications, surgical technique, and rehabilitation protocol]. / Die spezifische Rehabilitation nach Mikrofrakturierung bei Arthrose des Kniegelenkes. Mikrofrakturierung und spezifische Rehabilitation zur Behandlung von Arthrose des Kniegelenks. Indikationsstellung, operative Technik und Rehabilitationsprotokoll.

Treatment of osteoarthritis in young and middle-aged patients, in whom joint replacement is usually not appropriate, is a challenge to orthopaedic surgeons. Arthroscopic techniques can help control patients' symptoms. In particular, the microfracture procedure combined with management of the joint volume and a specific rehabilitation protocol shows good results in patients with osteoarthritis and cartilage defects by resurfacing the defect with a combination of types I and II cartilaginous tissue. Microfracture is a single-staged arthroscopic procedure that can be combined with any other arthroscopic treatment for osteoarthritis of the knee. With an appropriate rehabilitation protocol and techniques for controlling the joint volume, these treatments are very effective for pain relief and functional improvement. The described technique is our choice for initial surgical treatment of osteoarthritis of the knee.

Arthrocentesis in the management of internal derangement of the temporomandibular joint.

BACKGROUND: Temporomandibular disorders (TMD) cover a wide spectrum of disorder; myalgic, arthralgic and psychogenic. The procedure of TMJ arthrocentesis has a role in managing patients with arthralgic pain and limitation if they fail to respond to non-surgical therapy. METHOD: The patient records of a single private specialist OMS were searched over the 9-year period of 2006-2014 to identify patients who had arthrocentesis as part of their multidisciplinary management. The detailed demographic, diagnosis, pre and post arthrocentesis procedure were identified and put on a database. Appropriate statistics were performed. RESULTS: Seventy-six patients had 115 arthrocentesis procedures performed in the study period. Fifty of 76 had improvement in their pain and 16 of 41 had an increased jaw opening of more than 10 mm. There were no complications or morbidity. Analysis of patient variables generally showed no correlations. CONCLUSIONS: Temporomandibular joint arthrocentesis has a role in the multidisciplinary, multimodality treatment of arthralgic TMD.

Is there a role for pentoxifylline and tocopherol in the management of advanced osteoradionecrosis of the jaws with pathological fractures? Case reports and review of the literature.

Osteoradionecrosis (ORN) is an infrequent but serious complication of radiotherapy, especially in the head and neck region. It is a slowly progressive condition, with management in the early stages focused on symptom control, and surgery usually reserved for advanced ORN. However, established ORN is difficult to treat. The role of hyperbaric oxygen therapy has recently been contested. The use of pentoxifylline in the management of ORN was first described by Delanian in 2004, but its benefits have not been replicated in other studies. In cases of advanced ORN with pathological fractures, many centres still advocate surgical resection and reconstruction. However, in this group of patients who often have multiple medical comorbidities, many of whom have previously undergone significant surgery, a resective plan is not always ideal. This paper presents two successful cases of bony union after the use of pentoxifylline and tocopherol to manage grade III ORN of the mandible. Both patients had pathological fractures and orocutaneous fistulas and were deemed unsuitable for surgery. The possible reasons for the success of pentoxifylline and tocopherol are discussed, and a review of the current literature evidence of similar cases is presented. Pentoxifylline and tocopherol should be considered for the management of advanced ORN where surgical management is not appropriate.

Arctic cut-off high drives the poleward shift of a new Greenland melting record.

Large-scale atmospheric circulation controls the mass and energy balance of the Greenland ice sheet through its impact on radiative budget, runoff and accumulation. Here, using reanalysis data and the outputs of a regional climate model, we show that the persistence of an exceptional atmospheric ridge, centred over the Arctic Ocean, was responsible for a poleward shift of runoff, albedo and surface temperature records over the Greenland during the summer of 2015. New records of monthly mean zonal winds at 500 hPa and of the maximum latitude of ridge peaks of the 5,700±50 m isohypse over the Arctic were associated with the formation and persistency of a cutoff high. The unprecedented (1948-2015) and sustained atmospheric conditions promoted enhanced runoff, increased the surface temperatures and decreased the albedo in northern Greenland, while inhibiting melting in the south, where new melting records were set over the past decade.

Arthroscopy of the hip for patients with mild to moderate developmental dysplasia of the hip and femoroacetabular impingement: Outcomes following hip arthroscopy for treatment of chondrolabral damage.

The purpose of this study was to determine patient-reported outcomes of patients with mild to moderate developmental dysplasia of the hip (DDH) and femoroacetabular impingement (FAI) undergoing arthroscopy of the hip in the treatment of chondrolabral pathology. A total of 28 patients with a centre-edge angle between 15° and 19° were identified from an institutional database. Their mean age was 34 years (18 to 53), with 12 female and 16 male patients. All underwent labral treatment and concomitant correction of FAI. There were nine reoperations, with two patients requiring revision arthroscopy, two requiring periacetabular osteotomy and five needing total hip arthroplasty. Patients who required further major surgery were more likely to be older, male, and to have more severe DDH with a larger alpha angle and decreased joint space. At a mean follow-up of 42 months (24 to 89), the mean modified Harris hip score improved from 59 (20 to 98) to 82 (45 to 100; p < 0.001). The mean Western Ontario and McMaster Universities Osteoarthritis Index score improved from 30 (1 to 61) to 16 (0 to 43; p < 0.001). Median patient satisfaction was 9.0/10 (1 to 10). Patients reported excellent improvement in function following arthroscopy of the hip. This study shows that with proper patient selection, arthroscopy of the hip can be successful in the young patient with mild to moderate DDH and FAI.

Genetic polymorphisms in glutathione S-transferase mu and theta, N-acetyltransferase, and CYP1A1 and risk of gliomas.

The role of genetic polymorphisms in modulating susceptibility to carcinogenic exposures has been well explored for tobacco-related neoplasms but not for other neoplasms including gliomas. It is relevant to explore these polymorphisms because certain carcinogenic exposures such as nitrosamines are implicated in the risk of gliomas. We therefore conducted a pilot case-control study to examine the role of polymorphisms in GSTM1, GSTT1, NAT2 (rapid, intermediate, and slow acetylation), and CYP1A1 and risk of glioma. Ninety patients diagnosed with glioma were ascertained as part of an ongoing genetic epidemiological study and were age, gender, and race matched with 90 healthy controls. We used PCR based methodology to determine the prevalence of the above genetic polymorphisms using sequences and PCR conditions directly adapted from studies reported previously. We calculated univariate odds ratios and performed multiple logistic regression to assess interactions between polymorphisms. We found no statistically significant associations between the null genotypes of GSTM1 and GSTT1, and CYP1A1 and risk of gliomas. However, there was an intriguing pattern with NAT2 acetylation status (odds ratios, 1.81, 1.34, and 0.61 for rapid, intermediate, and slow acetylation, respectively; P = 0.10 for trend). It is unlikely that any single polymorphism is sufficiently predictive of risk, and a panel of markers integrated with epidemiological data should be conducted on a large number of study subjects to fully understand the role of genetic polymorphisms and brain tumor risk.

Comparative in vivo studies with paclitaxel and liposome-encapsulated paclitaxel.

Our study was designed to evaluate the pharmacokinetics, tissue distribution, toxicity and therapeutic efficacy of liposome-encapsulated paclitaxel (LET) in comparison to conventional paclitaxel. In normal mice, LET was much less toxic than the conventional drug. A dose of 32.5 mg/kg of conventional paclitaxel administered i.v. on three consecutive days produced 100% mortality by day three, while liposomal paclitaxel exhibited no mortality. The control group which received Diluent 12 (Chremophor EL and ethanol; 1:1 v/v), a vehicle used in conventional paclitaxel, 30% mortality was observed at this dosage level. In murine ascitic L1210 leukemia model, liposomal paclitaxel and conventional paclitaxel showed comparable antitumor activity. The pharmacokinetics of conventional paclitaxel and LET was studied in mice at dose levels of 5 mg/kg and 20 mg/kg. After intravenous administration of conventional paclitaxel at a dose of 5 mg/kg, the area under the plasma-concentration-time curve (AUC) was 2-fold lower and, the elimination half-life was 2-times shorter compared to LET. At a dose of 20 mg/kg, the terminal half-lives were comparable, however, conventional paclitaxel displayed non-linear pharmacokinetics with disproportionate increase in AUC. At the two dose levels studied, LET demonstrated linear kinetics. Tissue distribution of paclitaxel after administration of LET showed levels 10-fold higher in spleen and 3.5-fold higher in liver as compared to conventional paclitaxel. The significant decrease in toxicity shown by LET, coupled with an increase in plasma AUC and half-life indicates that LET may be a viable alternative to the therapeutic use of the conventional preparation of paclitaxel.

Type XV collagen in human colonic adenocarcinomas has a different distribution than other basement membrane zone proteins.

In situ carcinomas must penetrate their own basement membrane to be classified as invasive, and subsequently infiltrate surrounding connective tissue and cross vascular basement membranes to metastasize hematogenously. Accordingly, in many studies, integral basement membrane components, including type IV collagen, laminin, and heparan sulfate proteoglycan, have been localized in a spectrum of tumors to gain insight into their role in neoplasia. A number of recently identified extracellular matrix molecules and isoforms of the aforementioned proteins have been localized to the basement membrane zone, illustrating another level of biochemical heterogeneity in these structures. As the complexity of these matrices becomes more apparent, their roles in maintaining homeostasis and in tumor biology falls into question. Of the new group of collagens localized to the basement membrane zone, type XV was the first to be characterized (Cell Tissue Res, 286:493-505, 1996). This nonfibrillar collagen has a nearly ubiquitous distribution in normal human tissues via a strong association with basement membrane zones, suggesting that it functions to adhere basement membrane to the underlying stroma. To begin investigation of this protein in malignant tumors, we have localized type XV in human colonic adenocarcinomas and compared its distribution with that of type IV collagen and laminin. Collagens XV and IV and laminin were found in all normal and colonic epithelial, muscle, fat, neural, and vascular basement membrane zones, as shown previously. In moderately differentiated, invasive adenocarcinomas, laminin and type IV collagen were sometimes observed as continuous, linear deposits around some of the malignant glands, but more often they were seen in either discontinuous deposits or were completely absent. In contrast, type XV collagen was characterized as virtually absent from the basement membrane zones of malignant glandular elements in moderately differentiated tumors. Nevertheless there were also similarities; all 3 proteins were usually present in the stroma and adjacent vascular basement membrane zones surrounding invasive glands. The loss of type XV collagen from these malignant epithelial basement membrane zones and its increased interstitial expression suggests a role for this protein in the invasive process and the possibility that it may provide a sensitive indicator of tumor invasion.

Reversal of glaucomatous optic disc cupping in adult patients.

A prospective study of reversal of glaucomatous optic disc cupping was performed by topographic optic disc analysis using the optic nerve head analyzer (Rodenstock analyzer, G. Rodenstock Instrumente GMBH, Munich, West Germany) in 13 adults with chronic open angle glaucoma. Intraocular pressure decreased from the mean (+/- SD) initial intraocular pressure of 33.2 +/- 8.2 mm Hg to the final intraocular pressure of 16.9 +/- 6.1 mm Hg over 13.6 +/- 10.4 weeks. Mean (+/- SD) cup-disc ratio decreased significantly, from 0.573 +/- 0.207 to 0.499 +/- 0.198, and mean (+/- SD) neuroretinal rim area increased significantly, from 0.913 +/- 0.341 to 1.042 +/- 0.284 mm2. The decrease of mean (+/- SD) cup volume from 0.592 +/- 0.966 to 0.451 +/- 0.703 mm3 was only marginally significant. However, more meaningful was a finding that reversal of cup volume, like reversals of cup-disc ratio and rim area, was directly proportional to the percent IOP reduction (r = .669 for cup volume reversal; r = .626 for cup-disc ratio reversal; and r = .675 for rim area reversal).

Hepatic amino acid metabolism during hyperinsulinemia and hyperaminoacidemia in conscious rabbit during late pregnancy.

To test whether pregnancy has any effect on amino acid metabolism, we examined in two experimental conditions (1) the effect of hyperinsulinemia on the blood concentration and net hepatic balance of amino acids, and (2) the effect of hyperaminoacidemia on the hepatic handling of amino acids. Experiments were performed in conscious virgin and pregnant rabbits after an 18-hour fast. In the first protocol (hyperinsulinemia), an increment in the plasma insulin level (approximately 45 and 20 microU/mL in the portal vein and artery, respectively) with euglycemia maintained causes a similar decrease (approximately 27% to 34%) in blood amino acid concentrations without any changes in the net hepatic uptake of amino acids in both groups of animals. The hepatic uptake of branched-chain amino acids (BCAA) was practically negligible, whereas there was a consistent uptake of gluconeogenic amino acids in pregnant and nonpregnant rabbits. In the second protocol, hyperaminoacidemia leads to a significantly lower increase in the net hepatic uptake of glycine and serine in pregnant rabbits as compared with nonpregnant rabbits. The same trend was observed for the uptake of individual BCAA, but it did not reach statistical significance. We conclude that in pregnant rabbits (1) insulin does not modify the hepatic uptake of amino acids, and its ability to suppress the release of amino acids from peripheral tissues does not seem to be affected when compared with that in nonpregnant animals, and (2) when hyperaminoacidemia occurs, a greater amount of gluconeogenic amino acids (glycine and serine) would escape the liver, suggesting a higher availability of these circulating amino acids for the fetus.

Glutathione s-transferase genotypes as risk factors for head and neck cancer.

BACKGROUND: Several enzymatic systems, including glutathione S-transferases, are involved in the metabolism of environmental agents. The absence of glutathione S-transferases mu (GSTM1) and theta (GSTT1) results in decreased detoxification of carcinogens, for example, chemicals in cigarette smoke. These metabolic deficiencies may predispose individuals to the development of smoking-related tumors, such as cancers of the lung, head and neck, and bladder. METHODS: The glutathione S-transferase genotypes of 186 previously untreated patients with squamous cell carcinoma of the head and neck and 42 healthy controls were determined with polymerase chain reaction (PCR) methodologies. Lymphocytes separated from heparinized peripheral blood or whole blood extracts served as sources of genomic DNA. The presence or absence of the gene-specific PCR products revealed the positive or negative genotypes, respectively. RESULTS: The absence of the GSTM1 genotype conferred an odds ratio of 2.37, and the 95% confidence interval (CI) was 1.20 to 4.67. The absence of the GSTT1 gene conferred an odds ratio of 1.47 (CI 0.71 to 3.02). In the population of 42 patients and their matched 42 controls, the absence of the GSTM1 and GSTT1 genotypes conferred odds ratios of 3.10 (CI 1.24 to 7.75) and 2.18 (CI 0.91 to 5.23), respectively. CONCLUSIONS: Despite the small study size, our preliminary data suggest that genetically determined factors of carcinogen metabolism may be associated with increased risk for head and neck cancer.

Reconstruction of the anterior cruciate ligament in patients who are at least forty years old. A long-term follow-up and outcome study.

The long-term results were reviewed for seventy-two patients (seventy-five knees) who had had a bone-patellar ligament-bone intra-articular reconstruction of the anterior cruciate ligament between August 1984 and May 1992. The mean age of the patients at the time of the operation was forty-five years (range, forty to sixty years). Three patients had a bilateral procedure. The primary mechanisms of injury were accidents that occurred during skiing (thirty-two knees), tennis (fourteen knees), and soccer (five knees). We analyzed the responses to subjective questionnaires, the functional results, and the objective clinical data. The clinical examination included assessment of the range of motion, performance of Lachman and pivot-shift tests, and measurements with use of a KT-1000 arthrometer. All knees were evaluated with use of three common rating scales: that of Lysholm and Gillquist; that of The Hospital for Special Surgery, as modified by Insall et al.; and the International Knee Ligament Standard Evaluation Form. At the latest follow-up evaluation, at a mean of fifty-five months (range, twenty-six to 117 months), three patients reported pain or swelling. No patient reported giving-way or symptoms related to the patellofemoral joint. The mean range of extension was -12 to 6 degrees, compared with -8 to 42 degrees preoperatively, and the mean range of flexion was 112 to 150 degrees, compared with 52 to 154 degrees preoperatively. Flexion was limited to 112 degrees in one patient, but this was 5 degrees greater than that of the uninvolved knee. Sixty knees (80 per cent) had a negative pivot-shift test, and ten knees (13 per cent) had a grade of 1+. On testing with the KT-1000 device at maximum manual pressure, the mean difference between the injured and uninjured knees was found to have improved by 5.1 millimeters, from 6.4 millimeters preoperatively to 1.4 millimeters postoperatively (p < 0.01). The grade on the International Knee Ligament Standard Evaluation Form improved markedly; seventy-two knees (96 per cent) had a grade of C or D preoperatively, whereas seventy knees (93 per cent) had a grade of A or B postoperatively. The Hospital for Special Surgery score improved from a mean of 69 points preoperatively to a mean of 92 points postoperatively (p < 0.01). The mean score according to the scale of Lysholm and Gillquist increased from a mean of 63 points preoperatively to a mean of 94 points postoperatively (p < 0.01). All patients indicated that they were pleased with the result of the procedure. Bicycling was resumed at a mean of four months; jogging, at a mean of nine months; skiing, at a mean of ten months; and tennis, at a mean of twelve months.

Analytical methods for water disinfection byproducts in foods and beverages.

The determination of exposure to drinking water disinfection byproducts (DBPs) requires an understanding of how drinking water comes into contact with human through multiple pathways. In order to facilitate the investigation of human exposure to DBPs via foods and beverages, analytical method development efforts were initiated for haloacetonitriles, haloketones, chloropicrin, and the haloacetic acids (HAAs) in these matrices. The recoveries of the target analytes were investigated from composite foods and beverages. Individual foods and beverages used to investigate the general applicability of the developed methods were selected for testing based on their watercontent and frequency of consumption. The haloacetonitriles, the haloketones, and chloral hydrate were generally well recovered (70-130%), except for bromochloroacetonitrile (64%) and dibromoacetonitrile (55%), from foods spiked after homogenization and following extraction with methyl-t-butyl ether (MTBE); the addition of acetone was found to be necessary to improve recoveries from beverages. The process of homogenization resulted in decreased recoveries for the more volatile analytes despite the presence of dry ice. The HAAs were generally well recovered (70-130%), except for trichloroacetic acid (58%) and tribromoacetic acid (132%), from foods but low recoveries and emulsion formation were experienced with some beverages. With both groups of analytes, certain matrices were more problematic (as measured by volatility losses, emulsion formation) than others with regard to processing and analyte recovery.

Comparative injury rates of uninjured, anterior cruciate ligament-deficient, and reconstructed knees in a skiing population.

To evaluate the risks of skiing after anterior cruciate ligament injury with or without reconstruction, we performed a 3-year study of 5646 skiers employed by a large ski resort. All skiers underwent knee ligament examinations before entering the study. The participants were divided into three groups based on whether they had never had an anterior cruciate ligament injury (N = 4748), were unilaterally deficient of the ligament (N = 138), or had undergone a unilateral reconstruction of the ligament at least 1 year before (N = 274). The rates of knee injuries requiring evaluation by a physician or time off work were calculated. The results of the reconstructed knees were further evaluated to determine whether ligament repair with semitendinosus/gracilis or patellar tendon autograft had a higher injury rate. Compared with knees with intact anterior cruciate ligaments, ligament-deficient knees had a 6.2-times higher rate of injuries, and knees in which the ligament had been reconstructed had a 3.1-times higher rate. The differences between each of the three groups were significant. Injuries to ligament-intact knees were less severe, with 13% requiring surgery, while 39% of the injuries in the ligament-deficient and 41% of the injuries in the reconstructed-ligament knees required surgery. The rates of injury for the graft types were not significantly different, but skiers with a semitendinosus/gracilis tendon autograft were significantly more likely to rupture their graft than skiers with a patellar tendon autograft.

Anterior cruciate ligament injury incidence among male and female professional alpine skiers.

A retrospective review of anterior cruciate ligament injuries among professional alpine skiers was performed to compare sex-related differences in injury incidence. We screened 7155 ski patrollers or instructors (4537 men and 2618 women) for knee injuries before each ski season between 1991 and 1997. Screening involved a ski history questionnaire, a knee injury history questionnaire, and a knee physical examination. Any patient with an equivocal Lachman or pivot shift test was evaluated by KT-1000 arthrometry and excluded from the study if the manual maximum side-to-side difference was 3 mm or more. Thus, the study population was limited to subjects with intact anterior cruciate ligaments. Skiers injured during the study were identified through mandatory workers' compensation claims. Each injured skier was reevaluated using an injury questionnaire and physical examination. The men skied an average of 110 days per year (499,070 skier-days) and the women skied an average of 87 days per year (227,766 skier-days). Thirty-one skiing-related anterior cruciate ligament injuries were diagnosed, 21 in men and 10 in women. The incidence of ACL disruption was 4.2 injuries per 100,000 skier-days in men and 4.4 injuries per 100,000 skier-days in women. These data suggest that the incidences of anterior cruciate ligament injuries among male and female professional alpine skiers are similar.

Genetic Analysis of Adult-Plant Resistance to Leaf Rust in Five Spring Wheat Genotypes.

Inheritance of adult-plant resistance to leaf rust, caused by Puccinia triticina, was studied in the progeny of a one-way diallel cross involving five CIMMYT-derived adult-plant resistant wheat (Triticum aestivum) genotypes and a susceptible wheat 'Avocet-YrA'. F1 progenies, F2 populations, F2-derived F3, and F4-derived F5 lines were field evaluated under artificial epidemics with leaf rust race MCJ/SP. Adult-plant resistance to leaf rust was incompletely dominant in crosses with the susceptible parent and was found to be controlled by additive interactions of Lr34 with at least two to three additional genes. Transgressive segregation giving rise to plants or lines with higher and lower levels of resistance than the parents was observed in all F2 and F5 derivatives of the resistant-parent intercrosses and suggested that, apart from Lr34, some of the other additive genes were nonallelic. Although specific combining ability was significant in some generations, general combining ability was found to be the major component of variation. Among generations, the estimates of the narrow-sense heritability of adult-plant resistance to leaf rust ranged from 0.67 to 0.97.