Evidence for widespread changes in the structure, composition, and fire regimes of western North American forests.

Implementation of wildfire- and climate-adaptation strategies in seasonally dry forests of western North America is impeded by numerous constraints and uncertainties. After more than a century of resource and land use change, some question the need for proactive management, particularly given novel social, ecological, and climatic conditions. To address this question, we first provide a framework for assessing changes in landscape conditions and fire regimes. Using this framework, we then evaluate evidence of change in contemporary conditions relative to those maintained by active fire regimes, i.e., those uninterrupted by a century or more of human-induced fire exclusion. The cumulative results of more than a century of research document a persistent and substantial fire deficit and widespread alterations to ecological structures and functions. These changes are not necessarily apparent at all spatial scales or in all dimensions of fire regimes and forest and nonforest conditions. Nonetheless, loss of the once abundant influence of low- and moderate-severity fires suggests that even the least fire-prone ecosystems may be affected by alteration of the surrounding landscape and, consequently, ecosystem functions. Vegetation spatial patterns in fire-excluded forested landscapes no longer reflect the heterogeneity maintained by interacting fires of active fire regimes. Live and dead vegetation (surface and canopy fuels) is generally more abundant and continuous than before European colonization. As a result, current conditions are more vulnerable to the direct and indirect effects of seasonal and episodic increases in drought and fire, especially under a rapidly warming climate. Long-term fire exclusion and contemporaneous social-ecological influences continue to extensively modify seasonally dry forested landscapes. Management that realigns or adapts fire-excluded conditions to seasonal and episodic increases in drought and fire can moderate ecosystem transitions as forests and human communities adapt to changing climatic and disturbance regimes. As adaptation strategies are developed, evaluated, and implemented, objective scientific evaluation of ongoing research and monitoring can aid differentiation of warranted and unwarranted uncertainties.

Use, re-use or discard? Quantitatively defined variance in the functional integrity of N95 respirators following vaporized hydrogen peroxide decontamination during the COVID-19 pandemic.

BACKGROUND: Coronavirus disease 2019 has stretched the ability of many institutions to supply needed personal protective equipment, especially N95 respirators. N95 decontamination and re-use programmes provide one potential solution to this problem. Unfortunately, a comprehensive evaluation of the effects of decontamination on the fit of various N95 models using a quantitative fit test (QNFT) approach is lacking. AIMS: To investigate the effects of up to eight rounds of vaporized hydrogen peroxide (VHP) decontamination on the fit of N95 respirators currently in use in a hospital setting, and to examine if N95 respirators worn by one user can adapt to the face shape of a second user with no compromise to fit following VHP decontamination. METHODS: The PortaCount Pro+ Respirator Fit Tester Model 8038 was used to quantitatively define functional integrity, measured by fit, of N95 respirators following decontamination with VHP. FINDINGS: There was an observable downward trend in the functional integrity of Halyard Fluidshield 46727 N95 respirators throughout eight cycles of decontamination with VHP. Functional integrity of 3M 1870 N95 respirators was reduced significantly after the respirator was worn, decontaminated with VHP, and then quantitatively fit tested on a second user. Furthermore, inconsistencies between qualitative fit test and QNFT results were uncovered that may have strong implications on the fit testing method used by institutions. CONCLUSIONS: The data revealed variability in the functional integrity of different N95 models after VHP decontamination, and exposed potential limitations of N95 decontamination and re-use programmes.

Decontaminating N95 respirators during the COVID-19 pandemic: simple and practical approaches to increase decontamination capacity, speed, safety and ease of use.

BACKGROUND: The COVID-19 pandemic has caused a severe shortage of personal protective equipment (PPE), especially N95 respirators. Efficient, effective and economically feasible methods for large-scale PPE decontamination are urgently needed. AIMS: (1) to develop protocols for effectively decontaminating PPE using vaporized hydrogen peroxide (VHP); (2) to develop novel approaches that decrease set-up and take-down time while also increasing decontamination capacity; (3) to test decontamination efficiency for N95 respirators heavily contaminated by make-up or moisturizers. METHODS: We converted a decommissioned Biosafety Level 3 laboratory into a facility that could be used to decontaminate N95 respirators. N95 respirators were hung on metal racks, stacked in piles, placed in paper bags or covered with make-up or moisturizer. A VHP® VICTORY™ unit from STERIS was used to inject VHP into the facility. Biological and chemical indicators were used to validate the decontamination process. FINDINGS: N95 respirators individually hung on metal racks were successfully decontaminated using VHP. N95 respirators were also successfully decontaminated when placed in closed paper bags or if stacked in piles of up to six. Stacking reduced the time needed to arrange N95 respirators for decontamination by approximately two-thirds while almost tripling facility capacity. Make-up and moisturizer creams did not interfere with the decontamination process. CONCLUSIONS: Respirator stacking can reduce the hands-on time and increase decontamination capacity. When personalization is needed, respirators can be decontaminated in labelled paper bags. Make up or moisturizers do not appear to interfere with VHP decontamination.

The effects of sulforaphane on canine osteosarcoma proliferation and invasion.

Recent evidence in in vitro and in vivo models suggests that sulforaphane (SFN), found in raw cruciferous vegetables, may have utility in chemoprevention, as an antineoplastic agent and as a free radical scavenger. The effects of SFN alone or with doxorubicin on cell viability were examined, as well as cell cycle kinetics, invasion capabilities and apoptosis in three canine osteosarcoma cell line (D17, OS 2.4 and HMPOS). Results showed that SFN could not induce cell death at potentially physiological concentrations (<50 µM), but significantly diminished cell invasion and downregulation of focal adhesion kinase (FAK) signaling. Modest cell cycle changes were observed in each cell line. When doxorubicin was used in conjunction with SFN, there was a protective effect to doxorubicin-induced cytotoxicity in D17 and OS 2.4 cells. Further studies examining SFN as a supplement are warranted, particularly in light of pro-proliferative and cytoprotective properties in canine osteosarcoma.

The 5-lipoxygenase inhibitor tepoxalin induces oxidative damage and altered PTEN status prior to apoptosis in canine osteosarcoma cell lines.

The 5-lipoxygenase (5-LOX) inhibitor tepoxalin has been shown to slow canine osteosarcoma (OSA) tumour xenografts growth, yet the mechanisms are poorly elucidated. Further examination of tepoxalin in canine OSA cell lines shows that tepoxalin treated cells undergo apoptosis through caspase-3 activation and annexin staining. Interestingly, apoptosis is superseded by an increase in reactive oxygen species (ROS), as measured by activation of dihydrorhodamine 123 and mitosox. This increase in ROS appears to be related to the 5-LOX inhibitor regardless of cellular 5-LOX status, and was not observed after treatment with the tepoxalin metabolite RWJ20142. Additionally, 5-LOX inhibition by tepoxalin appears to increase phosphatase and tensin (PTEN) homolog activity by preventing its alkylation or oxidation. PTEN modification or inhibition allows phosphoinositide-3 (PI3) kinase activity thereby heightening activation of protein kinase B (AKT) phosphorylation. Our data suggest that off target oxidation and LOX inhibition play roles in the apoptotic response.

Influence of endurance and sprinting exercise on plasma adiponectin, leptin and irisin concentrations in racing Greyhounds and sled dogs.

OBJECTIVE: The objective of this study was to assess the effects of both short-term anaerobic exercise and long-term aerobic exercise on leptin, adiponectin and irisin concentrations in both sprint and endurance canine athletes. DESIGN: Prospective field trial repeated measures. The 25 racing Greyhounds were run over 400 m, with blood samples collected prior to exercise and at 10 min and 120 min after exercise. The 16 sled dogs were run an average of 3.5-5 h/day on 5 out of 8 days of stage stop racing competition, with assessment on days 0, 2 and 8. RESULTS: Baseline leptin concentrations were found to be lower than previously recorded values of domestic dogs, possibly because of a lower body fat content in athletes, with concentrations in sled dogs being slightly higher than those in Greyhounds. Baseline adiponectin concentrations in both groups of dogs, on average, were lower than most previously recorded values in domestic dogs; although unexpected, these findings may be attributed to differences in body fat content of the study population. CONCLUSION: Endurance exercise in sled dogs resulted in a persistent decrease in leptin that appears to be independent of race-associated weight loss, with no appreciable changes in adiponectin or irisin concentrations. The anaerobic exercise of Greyhounds produced no detectable changes in leptin and adiponectin concentrations; however, a significant rise in irisin 10 min post-exercise may be a compensatory mechanism for restoration of ATP homeostasis in skeletal muscle.

DNA gyrase and topoisomerase IV: biochemical activities, physiological roles during chromosome replication, and drug sensitivities.

DNA gyrase and topoisomerase IV are the two type II topoisomerases present in bacteria. Though clearly related, based on amino acid sequence similarity, they each play crucial, but distinct, roles in the cell. Gyrase is involved primarily in supporting nascent chain elongation during replication of the chromosome, whereas topoisomerase IV separates the topologically linked daughter chromosomes during the terminal stage of DNA replication. These different roles can be attributed to differences in the biochemical properties of the two enzymes. The biochemical activities, physiological roles, and drug sensitivities of the enzymes are reviewed.

Plasma vitamin D metabolites and C-reactive protein in stage-stop racing endurance sled dogs.

BACKGROUND: Dogs are a unique model for examining the effects of exercise on vitamin D status because of their lack of vitamin D synthesis by UV exposure. In addition, the inflammatory response may be associated with hypovitaminosis D. OBJECTIVES: To investigate the effects of several days of endurance exercise on plasma vitamin D (25-(OH)D3, 24,25-(OH)D3 and 1,25(OH)D3) and serum C-reactive protein (CRP) concentrations in stage-stop racing sled dogs. ANIMALS: 12 racing sled dogs and 8 control dogs. METHODS: Blood was collected before the race and immediately after racing on days 2 and 8. Plasma vitamin D metabolites and serum CRP concentrations were measured. RESULTS: Racing dogs showed a significant increase in 25(OH)D3 on day 2 (P = .027) and day 8 of the race (P < .001), whereas no increases were observed in control dogs. The plasma concentration of 24,25(OH)D3 showed a significant increase by day 8 (P < .001). There were no significant changes in 1,25(OH) D3 concentrations across all time points and groups. Racing dogs had significantly increased CRP concentrations by day 2 (39.3 ± 30.1 µg/mL; P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Increases in vitamin D metabolites as well as increases in CRP concentrations were observed in racing sled dogs. This finding was contrary to the hypothesis that decreases in vitamin D status in athletes may be related to the acute phase inflammatory response during exercise. In addition, the increased 24,25(OH)D3 concentrations compared to what is observed in other species suggests metabolic variations in dogs that lead to enhanced disposal of vitamin D.

Ethics, epidemiology, and women's health.

Ethical issues arise throughout the conduct of epidemiologic studies, in the processes of determining the study question, designing the protocol, and implementing the study. There also is an ethical dimension when studies are not done, for example, in studies of the effect of drugs and chemicals on male reproductive capacity. Harm as well as risk must be considered in the conduct of epidemiologic studies. The ethical principles that govern research, while independently justifiable, may come into conflict. Principles that govern research also may conflict with those that predominate in clinical practice. An example is the current controversy over unblinding anonymous, newborn human immunodeficiency virus seroprevalence studies to identify potentially infected infants. As women's health becomes more prominent on the research agenda, the resolution of these conflicts will become a complex challenge to epidemiologists, ethicists, clinicians, and the communities they serve.

New X-linked syndrome with seizures, acquired micrencephaly, and agenesis of the corpus callosum.

We report on 4 generations in a family with 3 living males, 3 males who died in infancy, and 3 females with neurologic impairment and agenesis of the corpus callosum (ACC). Manifestations in the surviving males include severe acquired micrencephaly, mental retardation, limb contractures, scoliosis, tapered digits with hyperconvex nails, a characteristic face with large eyes, prominent supraorbital ridges, synophris, optic atrophy, broad alveolar ridges and seizures. Urologic anomalies include renal dysplasia, cryptorchidism, and hypospadias. Two affected females were less severely impaired and continued to be socially responsive as adults, but had spastic quadriplegia and seizures. One obligate heterozygote was retarded with emotional problems while another obligate carrier female and her daughter were clinically normal. Pedigree analysis suggested X-linked inheritance with variable expression in females. These findings are inconsistent with the well-described X-linked conditions with ACC including FG syndrome and Aicairdi syndrome. ACC has not been described in Coffin-Lowry syndrome, a condition with similar clinical findings, which also demonstrates marked variability of expression in carrier females. In order to assist in carrier determination, brain imaging studies and DNA linkage analysis of the affected relatives was performed. We found a spectrum of agenesis of the corpus callosum with the most severe manifestations in the most severely affected males. DNA analysis using a series of X-linked probes suggests linkage with a LOD score of 1.26 at theta = 0 to a region between p 11.3 and p 21.3.

The economic value of informal caregiving.

This study explores the current market value of the care provided by unpaid family members and friends to ill and disabled adults. Using large, national data sets we estimate that the national economic value of informal caregiving was $196 billion in 1997. This figure dwarfs national spending for formal home health care ($32 billion) and nursing home care ($83 billion). Estimates for five states also are presented. This study broadens the issue of informal caregiving from the micro level, where individual caregivers attempt to cope with the stresses and responsibilities of caregiving, to the macro level of the health care system, which must find more effective ways to support family caregivers.

Social interventions in the care of human immunodeficiency virus (HIV)-infected pregnant women.

The incidence of infection with the human immunodeficiency virus (HIV) is increasing among women of childbearing age. Women now account for 18% of the total number of cases of the acquired immunodeficiency syndrome (AIDS), compared with 9% a decade ago. The medical care of pregnant HIV-infected women must take into account the high prevalence of substance abuse, preceded and often accompanied by significant levels of physical, emotional, and sexual trauma, and the concomitant stigmatization of these women in their families and communities. Pregnancy is often a time when women are motivated to make major positive behavioral and life-style changes. To do this, they need ongoing, multidisciplinary counseling and support, with recognition that progress may be intermittent and slow. The Special Prenatal Care Program at Bellevue Hospital is described to show the level of resource commitment that is needed as well as the nearly universal acceptance of voluntary HIV counseling and testing in these conditions. Trends in permanency planning for the children of HIV-infected women are described. Future research needs are outlined, including female-specific drug treatment and more effective contraceptive technology for both men and women.

Atypical fibrous histiocytoma in the skull of an infant. Case report.

This is a report of an atypical fibrous histiocytoma in the skull of an infant, who at the age of 3 months was noted to have a "lump" beneath the scalp in the right parietal region. It was about 2 cm in diameter, and the scalp was movable over it. Physical examination was otherwise normal. Radiographs showed erosion of the scalp deep on the palpable mass. At operation a neoplasm was found, which had destroyed the bone and invaded the adjacent temporal muscle and dura mater. The tumor was removed en bloc after the surrounding bone had been excised. Histological examination using light and electron microscopy revealed the tumor to be an atypical fibrous histiocytoma. Radiation therapy was not given. There has been no recurrence for 7 years.

Clinical observations of nebulized flunisolide in infants and young children with asthma and bronchopulmonary dysplasia.

Severe bronchopulmonary dysplasia (BPD) is frequently associated with asthma. The combination is often severe enough to necessitate corticosteroid therapy. There are no commercially available nebulizer solutions of corticosteroids for use in infants and young children. Seven infants and small children with very severe BPD and asthma aged 6-24 months, were treated with flunisolide, 187-250 micrograms q.i.d. in the form of nasal spray delivered by nebulizer. After treatment for 2.5-20 months, four patients showed clinical improvement, one initially improved but later deteriorated and died of cardiac failure, and two patients showed no improvement and died within 3 months. The number of days of hospitalization was significantly reduced from 8.4/month to 2.5/month (P less than 0.05). No side-effects were detected and it was felt that the three patients who died, did so as a consequence of very severe BPD and its cardiac consequences. The suspension remained stable for 80 min when mixed with normal saline, cromolyn sodium, albuterol, or acetylcysteine. It is concluded that nebulized flunisolide is a potentially useful treatment for infants and young children with asthma and BPD.

Role-taking standpoint and adolescent usage of Kohlberg's conventional stages of moral reasoning.

By taking into account a respondent's role-taking standpoint, this study proposes that moral judgments coded at Kohlberg's conventional stages can be expected to vary depending upon (a) the identity of the protagonist implicated in the moral dilemma and (b) the nature of the issues raised by the moral dilemmas used. Different groups of respondents were asked to answer three versions of Kohlberg's moral judgment questionnaire. One version implicated strangers in the dilemmas used (fictitious-other questionnaire), while the other two versions implicated respondents' best friends or mothers (primary-other questionnaires). A comparison of these questionnaire treatments indicates that Stage 3 response rate significantly increases and Stage 4 response rate significantly decreases when respondents answer primary-other questionnaires. It is suggested that this finding casts doubt on the adequacy of the displacement view of moral stage acquisition. The displacement perspective argues that as more cognitively complex structures are acquired, earlier acquired structures are displaced. In contrast, the present study proposes that a "nondisplacement" view of stage acquisition is required in order to explain variation observed at Stage 3 when it may be assumed that a Stage 4 reasoning capability has been acquired.

Intraoperative awakening to monitor spinal cord function during Harrington instrumentation and spine fusion. Description of procedure and report of three cases.

Since Vauzelle and associates first reported in 1973 on the functional monitoring of spinal cord activity during surgery on the spine, we have used intraoperative awakening routinely in patients undergoing surgery involving distraction of the spinal column. Of the 166 consecutive patients studied, three were discovered to have a neural deficiency when they were awakened during surgery. These deficits disappeared immediately on release of the distracting force. Although it is unlikely that all three patients would have proceeded to paraplegia, we believe that this is a safe and sensitive test which will identify patients in danger of neural complications.

Surgical treatment of congenital scoliosis with or without Harrington instrumentation.

Of thirty-one patients who underwent posterior fusion for congenital scoliosis from 1972 through 1977 at the Children's Hospital Medical Center, Boston, Massachusetts, and were followed for two years or more, eighteen (average age, fourteen and one-half years and average curve, 62 degrees) were treated by spine fusion using Harrington instrumentation, and thirteen (average age, and one-half years and average curve, 43 degrees) were treated by fusion without instrumentation. Correction of the curve in the instrumented group was obtained at operation, while in the group without instrumentation correction was attempted using a plaster jacket applied during the postoperative period. After an average follow-up of thirty-four months in the group with Harrington instrumentation, the average curve was reduced from 62 to 40 degrees, for an average correction of 22 degrees, while in the non-instrumented group, after an average follow-up of fifty-three months the average curve was reduced from 43 to 38 degrees, for an average correction 5 degrees. A myelogram using water-soluble contrast medium should be performed in all patients who are to have instrumentation and in all patients who have any neural abnormality or are suspected of having diastematomyelia. An intraoperative wake-up test was used in all patients who had instrumentation after 1973 and averted neural complications in one. Proper treatment of congenital scoliosis requires early recognition of curves that have already progressed or will certainly do so. Fusion without instrumentation then is sufficient. If correction is necessary, staged procedures (halo-femoral traction, anterior release, and posterior fusion) may be required for severe curves. For the less severe curves, instrumentation as the primary means of obtaining correction proved to be safe and effective in this small series, but should only be attempted by experienced surgeons in institutions with all of the necessary facilities.

Pitfalls in the CT diagnosis of appendicitis.

CT evaluation of appendicitis represents an increasingly common emergency room request. While the overall accuracy of CT is high, numerous pitfalls exist which may deceive radiologists, resulting in a missed diagnosis of appendicitis. The inflamed appendix may be unusual in its location, or may appear normal if only a small portion of the distal appendix is involved (tip appendicitis). In a patient with a history of appendectomy, inflammation of the appendiceal stump may be easily missed. Appendicitis may closely mimic small bowel obstruction, or gynaecological disease, especially after perforation has occurred. Even a misleading clinical history may lead the radiologist's eye astray. This pictorial review demonstrates these and other potential radiological pitfalls, and includes important points for the accurate diagnosis of appendicitis.

Radiology pitfalls in the use of barium enema in pediatric appendicitis.

Barium enema (BE) is usefull and safe in diagnosis of pediatric appendicitis, but pitfalls must be avoided. Reasons for false negative BE include failing to or inability to obtain good compression local views of the cecum and accepting a partially filled appendix as normal. In addition to right ovarian lesions in girls, there are less common causes of false positives, including mucocele, intussuscepted appendix, and recurrent inflammation of appendiceal stump. Non-filing of the appendix is not in itself abnormal. Abdominal ultrasound may be complementary, and increasingly is becoming the primary imaging modality for uncertain appendicitis.

The experiences and challenges of informal caregivers: common themes and differences among whites, blacks, and hispanics.

PURPOSE: This study examined commonalities and differences in the experiences and challenges of White, Black, and Hispanic informal caregivers in New York, NY. DESIGN AND METHODS: A randomly selected representative cross-section of 2,241 households was contacted through telephone interviews. Complete data were available for 380 eligible participants, who were classified as White (n = 164), Black (n = 129) and Hispanic (n = 87). Descriptive, bivariate, and multivariate analyses were conducted to examine differences in caregiving intensity, reported difficulty with providing care, and having unmet needs with care provision. RESULTS: Over 70% of caregivers had no help from formal caregivers, even though over 80% had been providing care for at least 1 year, and 40% had been providing this care for 20 or more hr per week. Compared with White caregivers, Black caregivers were more likely to provide higher intensity care, to report having unmet needs with care provision, and to experience increased religiosity since becoming caregivers, but were less likely to report difficulty with providing care. Hispanic caregivers were more likely than White caregivers to have help from formal caregivers and to experience increased religiosity since becoming caregivers. IMPLICATIONS: Although many similarities exist in the experiences and challenges of informal caregivers, gaining insight from different populations of family caregivers would help program planners, policy makers, and formal caregivers to develop and implement culturally sensitive programs and policies that are supportive of the needs of these caregivers in their ever-expanding roles. Future efforts also should focus on exploring the potentially significant role that community resources, in particular, religious institutions, could play in providing outreach and support to racial/ethnic minority caregivers.