The plausible effects of wearing face masks on sports performance - A scoping review

Objectives

The objectives of this scoping review are to discuss, firstly, the positive aspects of wearing face masks during training (such as a barrier to COVID-19 transmission, air pollutant exposure, and adding load on respiratory resistance flow); secondly, the negative aspects (adverse effects on body temperature and hypoxia risks); and thirdly, the training responses of wearing face masks on aerobic and anaerobic performance.

News

Besides social distancing and hand hygiene, wearing a face mask is proposed to be the prime advocacy for virus containment. During the period of high risk of contamination, the return to sport guidelines proposed by international and national sport federations included wearing face masks during training sessions. However, it is necessary to discuss the pros and cons of wearing face masks during exercise.

Prospects

Although it was essential to wear a face mask during exercise or sport-specific training, there is conflicting evidence on the implications of the use of face masks on physical, physiological as well as psychological well-being or performance. Based on the conflicting empirical findings and anecdotal evidence, certain recommendations have been made for adequate use of face masks during exercise; both to break the chain of transmission and prevent the physiological compromise expected from wearing face masks during exercise. The present review can help stakeholders balance sport guidelines in the event of a respiratory virus pandemic with athlete safety.

Conclusion

Conflicting evidence of mechanistic links between the dose of exercise and the possible adverse effects associated with exercising with face masks is available. Adequately powered studies with strong methodological quality on appropriate selection of masks and usage based on the intensity, duration, and type of sport, age, and gender is needed now for the stakeholders to make informed decisions with respect to exercising with face masks.

Can the Behaviour Intervention Plan Quality Evaluation, Version 2, be simplified for use by stakeholders with limited experience of positive behaviour support?

BACKGROUND

Behaviour support plan (BSP) quality auditing tools like the Behaviour Intervention Plan Quality Evaluation, Version 2 (BIPQEII), assess the quality of a BSP from the perspective of technical compliance with behavioural principles. However, these principles may be inaccessible to interested stakeholders with limited experience and knowledge of positive behaviour support (PBS). The aim of this study was to test if a simplified version of the BIPQEII [the Behaviour Support Plan Audit Tool (BSPA-tool)] offers a reliable and valid assessment of a BSP's technical compliance with behavioural principles when used by professional stakeholders with varying levels of PBS experience and knowledge.

METHODS

Four scorers rated 50 de-identified BSPs using the BSPA-tool, with one scorer also rating the BSPs using the BIPQEII. Four weeks later, each scorer rated 25 of the 50 BSPs again using the BSPA-tool. Prior to BSP scoring, a group of PBS practitioners provided feedback on the BSPA-tool's content validity.

RESULTS

The BSPA-tool was found to have acceptable content and parallel-form validity; however, acceptable internal consistency and inter-rater and intra-rater reliability were dependent on PBS experience/knowledge, that is, scorers with more experience/knowledge achieved more acceptable levels of reliability.

CONCLUSIONS

This study confirms that even with simplification, BSP quality auditing tools based on technical compliance with behavioural principles are still only accessible to stakeholders with extensive experience/knowledge of PBS. To engage less-experienced stakeholders in BSP quality auditing processes, new audit tools need to be developed that focus on other aspects of BSP quality (e.g. readability and consultation).

Myogenic and Central Neurogenic Factors in Fatigue in Multiple Sclerosis

Short episodes of electrical stimulation were applied to the right quadriceps muscle of patients with multiple sclerosis (MS) and healthy subjects at different times during 60 sec sustained voluntary muscle contractions at 0 to 100% levels of maximal voluntarily generated joint torque. The amplitude of electrically induced increments of torque (ΔT) has been shown to depend upon both the level of muscular contraction and time from the beginning of the contraction. The dependence of ΔT upon the time from the beginning of contraction has been assumed to reflect muscle fatigue. Patients with MS demonstrated an apparent involvement of central neurogenic mechanisms in fatigue manifested as a drop in muscle torque during sustained contractions at 75 and 100% levels when electrical stimulation was able to induce considerable increments in muscle torque. These patients also demonstrated a dependence of ΔT upon the contraction level suggesting that they did not produce maximal voluntary contraction torque in the pre-trial. Fatigue in MS is due to central, neurogenic factors and does not seem to involve any myogenic factors such as might be related to secondary muscle changes due to the long-standing disorder. The subjective feeling of tiredness (‘fatigue’) may be related to a dissociation between central motor commands (‘effort’) and their mechanical consequences.

Waiting Time Intervals for Non-small Cell Lung Cancer Diagnosis and Treatment in Alberta: Quantification of Intervals and Identification of Risk Factors Associated with Delays

AIMS

Very little is known regarding the time required to diagnose and treat patients with non-small cell lung cancer (NSCLC) in Canada. We sought to quantify diagnostic and treatment intervals for NSCLC care in Alberta and identify risk factors for delays.

MATERIALS AND METHODS

The Alberta Cancer Registry identified all cases of stage I-III NSCLC diagnosed and treated in Alberta, Canada from 2004 to 2011. Diagnostic data were obtained from physician billing, inpatient/outpatient hospital data and electronic medical records to quantify the duration of diagnostic and treatment intervals and their sum (system interval). Multivariable logistic regression was carried out to identify factors associated with delays.

RESULTS

Of the 3009 eligible patients included, the median and 90th percentile system interval was 78 (95% confidence interval 76-80) and 185 days (95% confidence interval 178-195), respectively. The treatment interval was longer than the diagnostic interval, with medians of 51 (95% confidence interval 49-53) and 38 (95% confidence interval 36-40) days, respectively. After adjustment, age > 60 years and treatment by modalities other than supportive care (especially surgery) were associated with delays. Factors associated with prompt care included high acuity presentations and stage III disease.

CONCLUSION

The majority of Albertans with potentially curable NSCLC exceeded guidelines for the timeliness of their care.

Whole body vibration therapy: a novel potential treatment for type 2 diabetes mellitus

There is a worsening epidemic of obesity and diabetes in the world. Life style interventions including dietary changes and increase in exercise can improve glucose metabolism and health in general. However, standard exercise programs are strenuous, time-consuming, and thus have low long-term compliance issues. We tested the feasibility of using high frequency, low amplitude whole body vibration (WBV) therapy to improve glucose metabolism in young type 2 diabetic (T2DM) mice. We also aimed to investigate the postulated anti-inflammatory and cytoprotective properties of WBV. Male db/db and db/m mice were exposed to high frequency, low-amplitude WBV. Outcome parameters comprised of body weight, hemoglobin A1c (HbA1c) level, as well as interleukin (IL)-17 (a marker of helper T cells), forkhead box P3 (Foxp3; a marker of regulatory T cells), and gammaH2AX (an index of DNA injury) expression. Furthermore, a 24 h metabolic cage study was carried out immediately after the WBV protocol and fluid intake, urine excretion and urine osmolality were determined. WBV did not affect body weight but improved HbA1c levels in db/db mice. Vibrated db/db mice demonstrated less fluid intake and urine excretion but better urinary concentrating ability than their non-vibrated controls. Pro-inflammatory changes were significantly reduced, as indicated by reduced IL-17 but increased Foxp3 expression. WBV reduced gammaH2AX in db/db mice suggestive of cytoprotective effect. However, WBV was largely without significant effects on assessed parameters in db/m mice. Collectively, our findings suggest that daily, short duration WBV may improve glycemic control, polydipsia, polyuria, and urine osmolality in T2DM in association with reduced inflammation. Thus, WBV may be a viable adjunctive treatment strategy in T2DM.

Trauma-Induced Parkinson’s Syndrome

Objectives:

Investigate if facial fractures predispose patients to developing Parkinson’s disease. Facial trauma ranges from lacerations to complex facial fractures. These fractures can result from sports, motor vehicle collisions, or assaults. The long-term neurologic effects of facial fractures have not been studied. Significant force is required to break midface buttresses or the mandible. Such force is transmitted toward the cranial vault contents. The location of the basal ganglia along the skull base predispose this area to higher strain. Chronic traumatic encephalopathy (CTE) shows similar neurologic damage related to repeated head injuries, as seen in the NFL and boxing.

Methods:

A total of 146 Parkinson’s patients were recruited from the neurology clinic. They were given a voluntary survey. This survey consisted of demographic questions: sex, age, age of diagnosis, involvement in sports, and history of facial fractures. The incidences of facial fracture ICD9 820.0 were analyzed with Wolfram Alpha and then chi-square.

Results:

Twenty-two of 146 (15%) had a positive history of facial fractures. Of the 22, 9 (6%) experienced multiple fractures. Twenty-six of 146 (17.8%) patients were involved in contact sports, with 7 out of 26 patients having fractures and participating in sports. Utilizing Wolfram Alpha, the incidence of ICD9 820.0 was calculated to be 1 out of 4100 (0.024%) in the US population. A chi-square test comparing our results showed a P value of .023

Conclusions:

Based on these statistically significant results, patients who experience facial fractures show an increased predilection for developing Parkinson’s disease.

Pharmacological reversal of histone methylation presensitizes pancreatic cancer cells to nucleoside drugs: in vitro optimization and novel nanoparticle delivery studies

We evaluated the potential of an investigational histone methylation reversal agent, 3-deazaneplanocin A (DZNep), in improving the chemosensitivity of pancreatic cancer to nucleoside analogs (i.e., gemcitabine). DZNep brought delayed but selective cytotoxicity to pancreatic cancer cells without affecting normal human pancreatic ductal epithelial (HPDE) cells. Co-exposure of DZNep and gemcitabine induced cytotoxic additivity or synergism in both well- and poorly-differentiated pancreatic cell lines by increased apoptosis. In contrast, DZNep exerted antagonism with gemcitabine against HPDE cells with significant reduction in cytotoxicity compared with the gemcitabine-alone regimen. DZNep marginally depended on purine nucleoside transporters for its cytotoxicity, but the transport dependence was circumvented by acyl derivatization. Drug exposure studies revealed that a short priming with DZNep followed by gemcitabine treatment rather than co-treatment of both agents to produce a maximal chemosensitization response in both gemcitabine-sensitive and gemcitabine-resistant pancreatic cancer cells. DZNep rapidly and reversibly decreased trimethylation of histone H3 lysine 27 but increased trimethylation of lysine 9 in an EZH2- and JMJD1A/2C-dependent manner, respectively. However, DZNep potentiation of nucleoside analog chemosensitization was found to be temporally coupled to trimethylation changes in lysine 27 and not lysine 9. Polymeric nanoparticles engineered to chronologically release DZNep followed by gemcitabine produced pronounced chemosensitization and dose-lowering effects. Together, our results identify that an optimized DZNep exposure can presensitize pancreatic cancer cells to anticancer nucleoside analogs through the reversal of histone methylation, emphasizing the promising clinical utilities of epigenetic reversal agents in future pancreatic cancer combination therapies.

Abstract 1025: Optimized DZNep exposure presensitizes pancreatic cancer cells to anticancer nucleoside analogues: potential clinical implications

We evaluated the potential of a histone methylation reversal agent 3-deazaneplanocin A (DZNep) in improving the chemosensitivity of pancreatic cancer to nucleoside analogs (i.e., gemcitabine). DZNep brought delayed but selective cytotoxicity to pancreatic cancer cells without affecting normal human pancreatic ductal epithelial (HPDE) cells. Co-exposure of DZNep and gemcitabine induced cytotoxic additivity or synergism in both well- and poorly-differentiated pancreatic cell lines. In contrast, DZNep exerted antagonism with gemcitabine against HPDE cells with significant reduction in cytotoxicity compared with the gemcitabine-alone regimen. DZNep marginally depended on purine nucleoside transporters for its cytotoxicity, but the transport dependence was circumvented by acyl derivatization. Drug exposure studies revealed that a short priming with DZNep followed by gemcitabine treatment rather than co-treatment of both agents produced a maximal chemosensitization response in both gemcitabine-sensitive and gemcitabine-resistant pancreatic cancer cells. DZNep rapidly and reversibly decreased trimethylation of histone H3 lysine 27 but increased trimethylation of lysine 9 in an EZH2- and JMJD1A/2C-dependent manner, respectively. However, DZNep potentiation of nucleoside analog chemosensitization was found to be temporally coupled to trimethylation changes in lysine 27 and not lysine 9. Polymeric nanoparticles engineered to chronologically release DZNep followed by gemcitabine produced pronounced chemosensitization and dose-lowering effects. Together, our results identify that an optimized DZNep exposure can presensitize pancreatic cancer cells to anticancer nucleoside analogs and emphasize the promising clinical utilities of histone methylation reversal agents in future pancreatic cancer combination therapies.

Citation Format: Sau Wai Hung, Hardik Mody, Sean Marrache, Yangzom D. Bhutia, Franklin Davis, Jong Hyun Cho, Shanta Dhar, Chung K. Chu, Rajgopal Govindarajan. Optimized DZNep exposure presensitizes pancreatic cancer cells to anticancer nucleoside analogues: potential clinical implications. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1025. doi:10.1158/1538-7445.AM2013-1025

A membrane-based ELISA assay and electrochemical immunosensor for microcystin-LR in water samples

We describe within this paper the development of an affinity sensor for the detection of the cyanobacterial toxin microcystin-LR. The first stage of the work included acquiring and testing of the antibodies to this target. Following the investigation, a heterogeneous direct competitive enzyme-linked immunosorbent assay (ELISA) format for microcystin-LR detection was developed, achieving a detection limit, LLD(80) = 0.022 μg L(-1). The system was then transferred to an affinity membrane sorbent-based ELISA. This was an amenable format for immunoassay incorporation into a disposable amperometric immunosensor device. This membrane-based ELISA achieved a detection limit, LLD(80) = 0.06 μg L(-1). A three-electrode immunosensor system was fabricated using thick-film screen-printing technology. Amperometric horseradish peroxidase transduction of hydrogen peroxide catalysis, at low reducing potentials, versus Ag/AgCl reference and carbon counter electrodes, was facilitated by hydroquinone-mediated electron transfer. A detection limit of 0.5 μg L(-1) for microcystin-LR was achieved. Similar levels of detection could be obtained using direct electrochemical sensing of the dye produced using the membrane-based ELISA. These techniques proved to be simple, cost-effective, and suitable for the detection of microcystin-LR in buffer and spiked tap and river water samples.

The teacher as observer and experimenter in the modification of disputing and talking-out behaviors

Disputing and talking-out behaviors of individual pupils and entire classroom groups in special education classes and regular classes from white middle-class areas and from all black poverty areas ranging from the first grade to junior high school were studied. The classroom teacher in each case acted as the experimenter and as an observer. Various means of recording behaviors were used and reliability of observation was checked by an outside observer, another teacher, a teacher-aide, a student, or by using a tape recorder. Observation sessions varied from 15 min to an entire school day. After baseline rates were obtained, extinction of inappropriate disputing or talking-out behaviors and reinforcement of appropriate behavior with teacher attention, praise and in some cases a desired classroom activity or a surprise at the end of the week brought a decrease in undesired verbalizations. A reversal of contingencies brought a return to high levels of inappropriate talking with a return to low levels when reinforcement for appropriate talking was reinstated. The experiments demonstrated that teachers in a variety of classroom settings could obtain reliable observational records and carry out experimental manipulations successfully using resources available in most schools.

Solid cancer incidence and low-dose-rate radiation exposures in the Techa River cohort: 1956 2002

BACKGROUND

This is the first analysis of solid cancer incidence in the Techa River cohort, a general population of men and women of all ages who received chronic low-dose rate exposures from environmental radiation releases associated with the Soviet nuclear weapons programme. This cohort provides one of the few opportunities to evaluate long-term human health risks from low-dose radiation exposures.

METHODS

Cancer incidence rates in this cohort were analysed using excess relative risk (ERR) models. The analyses make use of individualized dose estimates that take into account residence history, age and other factors. Cases are identified on the basis of continuing, active follow-up of mortality and cancer incidence.

RESULTS

Based on 1836 solid cancer cases with 446 588 person years accrued over 47 years of follow-up, solid cancer incidence rates were found to increase with dose and about 3% of the cases were attributable to radiation exposure. The ERR was 1.0/Gy (P = 0.004 95% CI (0.3; 1.9) in a linear dose-response model. There was no significant non-linearity in the dose response and no indication of effect modification by gender, ethnicity, attained age or age at first exposure.

CONCLUSIONS

The Techa River cohort provides strong evidence that low-dose, low-dose rate exposures lead to significant increases in solid cancer risks that appear to be linear in dose. The results do not suggest that risks associated with low-dose rate exposures are less than those seen following acute exposures such as were received by atomic bomb survivors.

Estimating anisotropic pollen dispersal: a case study in Quercus lobata

The pollen dispersal distribution is an important element of the neighbourhood size of plant populations. Most methods aimed at estimating the dispersal curve assume that pollen dispersal is isotropic, but evidence indicates that this assumption does not hold for many plant species, particularly wind-pollinated species subject to prevailing winds during the pollination season. We propose here a method of detecting anisotropy of pollen dispersal and of gauging its intensity, based on the estimation of the differentiation of maternal pollen clouds (TWOGENER extraction), assuming that pollen dispersal is bivariate and normally distributed. We applied the new method to a case study in Quercus lobata, detecting only a modest level of anisotropy in pollen dispersal in a direction roughly similar to the prevailing wind direction. Finally, we conducted a simulation to explore the conditions under which anisotropy can be detected with this method, and we show that while anisotropy is detectable, in principle, it requires a large volume of data.

The effect of a range of disinfectants on the dimensional accuracy and stability of some impression materials

Disinfection of dental impressions should be considered as a routine procedure in dental surgeries and dental laboratories. Disinfectants can have deleterious effects on some properties of impression materials. The aim of this study was to evaluate the dimensional accuracy and dimensional stability of a model dental stone, reproduced from five commonly used impression materials (Aquasil soft putty/Aquasil Ultra LV; Aquasil Monophase; Aquasil Ultra Heavy; Impregum F and Provil putty/Provil Light CD wash) retained by their adhesives in acrylic resin trays and exposed to three disinfectant solutions (Perform ID; Haz-Tabs and MD 520). Two hundred models were used to investigate the effect of the three disinfectants on the dimensional accuracy of the five impression materials. Five impressions were taken for each impression material for each disinfection treatment group. Measurements were carried out using a High Precision Reflex Microscope. All materials demonstrated a percentage change in dimensions when subjected to no disinfection when compared to the brass master die and all materials demonstrated a percentage change in dimension when subjected to the different disinfection procedures. The results of this study have demonstrated that for all of the materials investigated, the changes in dimensional stability were small in the order of microns. These changes may however be of clinical significance for procedures requiring a high degree of accuracy, for example fixed prosthodontics. The materials respond differently depending on the disinfectant used and it may therefore be appropriate that manufacturers recommend the use of particular disinfectants for their products in order to ensure optimum dimensional accuracy and stability.

The Techa River Cohort: Study Design and Follow-up Methods

Residents living on the banks of the Techa River in the Southern Urals region of Russia were exposed to radioactive contamination from the Mayak plutonium production and separation facility that discharged liquid radioactive waste into this river. This paper describes the methods used to establish and follow the Extended Techa River Cohort (ETRC), which includes almost 30,000 people living along the Techa River who were exposed to a complex mixture of radionuclides, largely 90Sr and 137Cs. The system of regular follow-up allows ascertainment of vital status, cause of death and cancer incidence. With over 50 years of follow-up and over 50% deceased, the ETRC now provides a valuable opportunity to study a wide range of health effects, both early and late, associated with protracted internal and external radiation exposures. The wide range of doses allows analysis of the nature of the dose-response relationship based on internal comparisons. Other features of the cohort are the high proportion (40%) exposed under age 20, and the inclusion of both sexes. The limitations of the study include loss to follow-up due to difficulties in tracing some cohort members and migration and incomplete ascertainment of cause of death.

Pyroelectric and conduction properties of Z-type calix[4] acid Langmuir-Blodgett films

Non-centrosymmetric Z-type Langmuir-Blodgett (LB) films were prepared by transferring a calix[4] acid monolayer from a subphase of Millipore water (18 Momegacm(-1)) onto aluminised glass substrates. Electrical measurements were performed at room temperature on LB films with a sandwich structure comprising a 50 nm thick thermally evaporated aluminium film. A pyroelectric figure of merit of 2.23 microC m(-2)K(-1) is reported for this LB system. The low voltage value of conductivity is 1.82 x 10(-12) Sm(-1). The electrode-limited Schottky effect is responsible for the conduction mechanism at a relatively high field due to the dc bias and the barrier potential height is determined to be 1.72 eV. The ac conductance for both samples shows a typical power law dependence with a value of approximately 0.86 for the exponent.

Sonochemically fabricated microelectrode arrays for biosensors—part II

A polymer-modified sonochemically fabricated glucose oxidase microelectrode array with microelectrode population densities of up to 2.5 x 10(5) microelectrodes per square centimetres is reported. These microelectrode sensors were formed by first depositing an insulating film on commercial screen printed electrodes which was subsequently sonicated to form cavities of regular sizes in the film. Electropolymerisation of aniline at the microelectrode cavities formed polyaniline protrusions containing entrapped glucose oxidase. Chemical deposition of polysiloxane from dichlorodimethysilane was used to deposit a thin protective and diffusion mass transport controlling coating over the electrodes. The physical and electrochemical properties of these films were studied. The performance of the final glucose oxidase based microelectrode sensor array is reported.

Risk of disease in siblings of patients with hereditary hemochromatosis

BACKGROUND

Parents of hereditary hemochromatosis (HH) homozygote patients, who are predominantly HH heterozygotes, have been found to have an increased risk of colonic neoplasia, diabetes, stroke death, stomach cancer and leukemia. The health histories of siblings of HH patients are reported.

METHODS

Individuals homozygous for HH were mailed questionnaires concerning the health histories of their siblings. Spouses of the HH homozygotes were asked to complete accompanying questionnaires concerning their siblings. The frequencies of serious illness and, when specified, each reported disease were determined by zygosity, odds ratios and 95% confidence intervals estimated.

RESULTS

Data were available for 279 siblings known to be HH homozygotes (HHs), and 1,265 other siblings of HH patients, who are predominantly hemochromatosis heterozygotes (HHhet). Controls consisted of 1,338 spouse siblings in whom only the general population prevalence of HH homozygosity and heterozygosity existed. Odds ratios comparing HH strata to controls were elevated for serious illness (1.12 in HHhet, 1.71 in HHs), diabetes (0.78, 2.45), arthritis (2.10, 1.69), and hepatoma (1.06, 11.96).

CONCLUSIONS

There was a significant trend for increased risk of serious illness among siblings of HH patients with increasing exposure to the HH gene, especially for diabetes, arthritis and hepatoma.

Contribution of age and gender to outcome of blunt splenic injury in adults: multicenter study of the eastern association for the surgery of trauma

BACKGROUND

The purpose of this study was to examine the contribution of age and gender to outcome after treatment of blunt splenic injury in adults.

METHODS

Through the Multi-Institutional Trials Committee of the Eastern Association for the Surgery of Trauma (EAST), 1488 adult patients from 27 trauma centers who suffered blunt splenic injury in 1997 were examined retrospectively.

RESULTS

Fifteen percent of patients were 55 years of age or older. A similar proportion of patients > or = 55 went directly to the operating room compared with patients < 55 (41% vs. 38%) but the mortality for patients > or = 55 was significantly greater than patients < 55 (43% vs. 23%). Patients > or = 55 failed nonoperative management (NOM) more frequently than patients < 55 (19% vs. 10%) and had increased mortality for both successful NOM (8% vs. 4%, p < 0.05) and failed NOM (29% vs. 12%, p = 0.054). There were no differences in immediate operative treatment, successful NOM, and failed NOM between men and women. However, women > or = 55 failed NOM more frequently than women < 55 (20% vs. 7%) and this was associated with increased mortality (36% vs. 5%) (both p < 0.05).

CONCLUSION

Patients > or = 55 had a greater mortality for all forms of treatment of their blunt splenic injury and failed NOM more frequently than patients < 55. Women > or = 55 had significantly greater mortality and failure of NOM than women < 55.

Beta-amyloid plaques induce neuritic dystrophy of nitric oxide-producing neurons in a transgenic mouse model of Alzheimer's disease

A causative role for nitric oxide has been postulated in a number of neurodegenerative diseases. Using histochemical and immunohistochemical methods, we examined the effect of beta-amyloid plaques on nitric oxide-producing cells in transgenic mice which overexpress a mutant human amyloid precursor protein (APP). In 14-month-old animals, nitric oxide synthase (NOS)-positive dystrophic neurites were observed frequently in the cerebral cortex and hippocampus of all of 16 plaque-bearing transgenic animals and in none of 16 wild-type animals. Double labeling of NOS and beta-amyloid revealed that 90% of beta-amyloid plaques were associated with NOS-containing dystrophic neurites. In 7-month-old animals, beta-amyloid plaques were very rare, but those present were frequently associated with NOS-positive neuritic dystrophy. We conclude that beta-amyloid plaques induce neuritic dystrophy in cortical neurons containing NOS in this model of AD, and hypothesize that this finding may be relevant to the mechanism of beta-amyloid neurotoxicity in human AD.

Anthropometric indices as predictors of survival in AIDS adults. Aquitaine Cohort, France, 1985-1997. Groupe d'Epidémiologie Clinique du Sida en Aquitaine (GECSA)

The aim of the study was to assess the performance of weight related nutritional markers [reported involuntary weight loss (WL) greater than 10%, measured WL and body mass index (BMI)] in predicting survival at AIDS stage. The three anthropometric indices were used as time dependent variables in Cox models to predict survival at AIDS stage. The studied sample included 630 HIV1-infected individuals of a prospective cohort of those 421 died (median survival at AIDS stage: 19.9 months). After adjustment for usual prognostic factors of survival, the reported WL greater than 10% was a pejorative predictor of survival (hazard ratio (HR) 2.4; 95% confidence interval (CI): 1.9-3.0). For measured WL < 5%, between 5 and 10% and > or = 10% of baseline weight compared with no WL, HR were respectively, 1.9 (CI: 1.4-2.6), 3.3 (CI: 2.4-4.4) and 6.7 (CI: 5.2-8.6). The HR of death were 2.2 (CI: 1.6-3.0) for BMI between 16 and 18.4 kg/m2 and 4.4 (CI: 3.1-6.3) for BMI < 16 compared to normal BMI (> or = 18.5). Even a limited WL measured at a given point in time during follow up increases the risk of death at the AIDS stage. Simple cross-sectional measures of BMI have a good predictive value of survival.