Higher Beetle Diversity in Native Vegetation Than in Stands of the Invasive Arundo, Arundo donax L., along the Rio Grande Basin in Texas, USA.

Within the cattle fever tick quarantine zone along the Rio Grande, a steady displacement of native vegetation by Arundo donax L. has been occurring for over a century. Arundo rapidly grows to a height of 3-6 m creating a dense wall of vegetation impeding surveillance and interception of stray cattle breaching the cattle fever tick quarantine from Mexico. Additionally, arundo monocultures may decrease the number and diversity of predatory beetles feeding on cattle fever ticks. To compare predatory beetle abundance and diversity within and between arundo and native vegetation, beetles were trapped at 10 locations twice a month for 16 mo (=38,400 trap nights) in the cattle fever tick quarantine zone along the Mexico-American border between Brownsville and Del Rio, TX. In total, 766 beetles were trapped, which included 34 genera and 43 species. Native vegetation provided more beetles, greater species richness, and increased biological diversity. Thus, greater beetle diversity was found in the more complex native vegetation compared with arundo stands. However, because predatory beetle sample numbers were modest, it is unlikely these mostly polyphagous, opportunistic arthropod predators would apply much pressure on tick populations, leading us to conclude that beetle predation would have little effect on tick populations in native vegetation or within stands of arundo.

Resolution of inter and intra-species relationships of the West Indian fruit fly Anastrepha obliqua.

The West Indian fruit fly, Anastrepha obliqua (Diptera: Tephritidae), is an economically important pest that inhabits areas of South and Central America, Mexico and the Caribbean with occasional infestations in the southern United States. We examine intra-specific relationships within A. obliqua as well as interspecific relationships to other Anastrepha species using a multi-locus data set comprising nine loci (seven nuclear, two mitochondrial) with 105 operational taxonomic units. The results based on a concatenated set of nuclear loci strongly support the monophyly of A. obliqua and most of the other species previously identified by morphology. A split between Peruvian A. obliqua samples and those from other locations was also identified. These results contrast with prior findings of relationships within A. obliqua based on mitochondrial data, as we found a marked discrepancy between nuclear and mitochondrial loci. These analyses suggest that introgression, particularly between A. obliqua and fraterculus species, may be one explanation for the discrepancy and the high mitochondrial diversity reported for A. obliqua could be the result of incomplete lineage sorting.

Glucagon increases energy expenditure independently of brown adipose tissue activation in humans.

AIMS: To investigate, for a given energy expenditure (EE) rise, the differential effects of glucagon infusion and cold exposure on brown adipose tissue (BAT) activation in humans. METHODS: Indirect calorimetry and supraclavicular thermography was performed in 11 healthy male volunteers before and after: cold exposure; glucagon infusion (at 23 °C); and vehicle infusion (at 23 °C). All volunteers underwent (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/CT scanning with cold exposure. Subjects with cold-induced BAT activation on (18)F-FDG PET/CT (n = 8) underwent a randomly allocated second (18)F-FDG PET/CT scan (at 23 °C), either with glucagon infusion (n = 4) or vehicle infusion (n = 4). RESULTS: We observed that EE increased by 14% after cold exposure and by 15% after glucagon infusion (50 ng/kg/min; p < 0.05 vs control for both). Cold exposure produced an increase in neck temperature (+0.44 °C; p < 0.001 vs control), but glucagon infusion did not alter neck temperature. In subjects with a cold-induced increase in the metabolic activity of supraclavicular BAT on (18)F-FDG PET/CT, a significant rise in the metabolic activity of BAT after glucagon infusion was not detected. Cold exposure increased sympathetic activation, as measured by circulating norepinephrine levels, but glucagon infusion did not. CONCLUSIONS: Glucagon increases EE by a similar magnitude compared with cold activation, but independently of BAT thermogenesis. This finding is of importance for the development of safe treatments for obesity through upregulation of EE.

Targeted siRNA Screens Identify ER-to-Mitochondrial Calcium Exchange in Autophagy and Mitophagy Responses in RPE1 Cells.

Autophagy is an important stress response pathway responsible for the removal and recycling of damaged or redundant cytosolic constituents. Mitochondrial damage triggers selective mitochondrial autophagy (mitophagy), mediated by a variety of response factors including the Pink1/Parkin system. Using human retinal pigment epithelial cells stably expressing autophagy and mitophagy reporters, we have conducted parallel screens of regulators of endoplasmic reticulum (ER) and mitochondrial morphology and function contributing to starvation-induced autophagy and damage-induced mitophagy. These screens identified the ER chaperone and Ca2+ flux modulator, sigma non-opioid intracellular receptor 1 (SIGMAR1), as a regulator of autophagosome expansion during starvation. Screens also identified phosphatidyl ethanolamine methyl transferase (PEMT) and the IP3-receptors (IP3Rs) as mediators of Parkin-induced mitophagy. Further experiments suggested that IP3R-mediated transfer of Ca2+ from the ER lumen to the mitochondrial matrix via the mitochondrial Ca2+ uniporter (MCU) primes mitochondria for mitophagy. Importantly, recruitment of Parkin to damaged mitochondria did not require IP3R-mediated ER-to-mitochondrial Ca2+ transfer, but mitochondrial clustering downstream of Parkin recruitment was impaired, suggesting involvement of regulators of mitochondrial dynamics and/or transport. Our data suggest that Ca2+ flux between ER and mitochondria at presumed ER/mitochondrial contact sites is needed both for starvation-induced autophagy and for Parkin-mediated mitophagy, further highlighting the importance of inter-organellar communication for effective cellular homeostasis.

Possible pro-carcinogenic association of endotoxin on lung cancer among Shanghai women textile workers.

BACKGROUND: Endotoxin (lipopolysaccharide) is a widespread contaminant in many environmental settings. Since the 1970s, there has been generally consistent evidence indicating reduced risks for lung cancer associated with occupational endotoxin exposure. METHODS: We updated a case-cohort study nested within a cohort of 267,400 female textile workers in Shanghai, China. We compared exposure histories of 1456 incident lung cancers cases diagnosed during 1989-2006 with those of a reference subcohort of 3022 workers who were free of lung cancer at the end of follow-up. We applied Cox proportional hazards modelling to estimate exposure-response trends, adjusted for age and smoking, for cumulative exposures lagged by 0, 10, and 20 years, and separately for time windows of ⩽15 and >15 years since first exposure. RESULTS: We observed no associations between cumulative exposure and lung cancer, irrespective of lag interval. In contrast, analyses by exposure time windows revealed modestly elevated, but not statistically significant relative risks (∼1.27) at the highest three exposure quintiles for exposures that occurred >15 years since first exposure. CONCLUSIONS: The findings do not support a protective effect of endotoxin, but are suggestive of possible lung cancer promotion with increasing time since first exposure.

Impaired OMA1-dependent cleavage of OPA1 and reduced DRP1 fission activity combine to prevent mitophagy in cells that are dependent on oxidative phosphorylation.

Mitochondrial dynamics play crucial roles in mitophagy-based mitochondrial quality control, but how these pathways are regulated to meet cellular energy demands remains obscure. Using non-transformed human RPE1 cells, we report that upregulation of mitochondrial oxidative phosphorylation alters mitochondrial dynamics to inhibit Parkin-mediated mitophagy. Despite the basal mitophagy rates remaining stable upon the switch to dependence on oxidative phosphorylation, mitochondria resist fragmentation when RPE1 cells are treated with the protonophore carbonyl cyanide m-chlorophenyl hydrazone. Mechanistically, we show that this is because cleavage of the inner membrane fusion factor L-OPA1 is prevented due to the failure to activate the inner membrane protease OMA1 in mitochondria that have a collapsed membrane potential. In parallel, mitochondria that use oxidative phosphorylation are protected from damage-induced fission through the impaired recruitment and activation of mitochondrial DRP1. Using OMA1-deficient MEF cells, we show that the preservation of a stable pool of L-OPA1 at the inner mitochondrial membrane is sufficient to delay mitophagy, even in the presence of Parkin. The capacity of cells that are dependent on oxidative phosphorylation to maintain substantial mitochondrial content in the face of acute damage has important implications for mitochondrial quality control in vivo.

Catastrophic antiphospholipid syndrome with concurrent thrombotic and hemorrhagic manifestations.

Antiphospholipid syndrome (APS) is a distinct autoimmune prothrombotic disorder due to pathogenic autoantibodies directed against proteins that bind to phospholipids. APS is characterized by arterial and venous thrombosis and their clinical sequelae. Catastrophic antiphospholipid syndrome (CAPS) is a rare and often fatal form of APS characterized by disseminated intravascular thrombosis and ischemic injury resulting in multiorgan failure. Rarely, intravascular thrombosis in CAPS is accompanied by hemorrhagic manifestations such as diffuse alveolar hemorrhage. Here, we report a 43-year-old woman who presented with anemia, acute gastroenteritis, abnormal liver function tests, bilateral pulmonary infiltrates, and a systemic inflammatory response syndrome. The patient developed respiratory failure as a result of diffuse alveolar hemorrhage followed by acute renal failure. Laboratory tests disclosed hematuria, proteinuria, and reduced platelet count. Microbiologic tests were negative. A renal biopsy demonstrated acute thrombotic microangiopathy and extensive interstitial hemorrhage. Serologic tests disclosed antinuclear antibodies and reduced serum complement C4 concentration. Coagulation studies revealed the lupus anticoagulant and autoantibodies against cardiolipin, beta 2-glycoprotein I, and prothrombin. High-dose glucocorticoids and plasma exchange resulted in rapid resolution of pulmonary, renal, and hematological manifestations. This rare case emphasizes that CAPS can present with concurrent thrombotic and hemorrhagic manifestations. Rapid diagnosis and treatment may result in complete recovery.

A cryptic mitochondrial targeting motif in Atg4D links caspase cleavage with mitochondrial import and oxidative stress.

The Atg4 cysteine proteases play crucial roles in the processing of Atg8 proteins during autophagy, but their regulation during cellular stress and differentiation remains poorly understood. We have found that two Atg4 family members--Atg4C and Atg4D--contain cryptic mitochondrial targeting sequences immediately downstream of their canonical (DEVD) caspase cleavage sites. Consequently, caspase-cleaved Atg4D (ΔN63 Atg4D) localizes to the mitochondrial matrix when expressed in mammalian cells, where it undergoes further processing to a ~42 kDa mitochondrial form. Interestingly, caspase cleavage is not needed for Atg4D mitochondrial import, because ~42 kDa mitochondrial Atg4D is observed in cells treated with caspase inhibitors and in cells expressing caspase-resistant Atg4D (DEVA(63)). Using HeLa cell lines stably expressing ΔN63 Atg4D, we showed that mitochondrial Atg4D sensitizes cells to cell death in the presence of the mitochondrial uncoupler, CCCP, and that mitochondrial cristae are less extensive in these cells. We further showed that the organization of mitochondrial cristae is altered during the mitochondrial clearance phase in differentiating primary human erythroblasts stably expressing ΔN63 Atg4D, and that these cells have elevated levels of mitochondrial reactive oxygen species (ROS) during late stages of erythropoiesis. Together these data suggest that the import of Atg4D during cellular stress and differentiation may play important roles in the regulation of mitochondrial physiology, ROS, mitophagy and cell viability.

Immune reconstitution renal-limited sarcoidosis presenting as acute kidney injury.

An HIV-infected asymptomatic woman developed acute kidney injury six weeks after initiation of combination antiretroviral therapy (cART). A renal biopsy revealed both renal-limited sarcoidosis and HIV nephropathy. The acute renal injury reversed with glucocorticoid therapy.

Lung cancer and occupational exposures other than cotton dust and endotoxin among women textile workers in Shanghai, China.

OBJECTIVES: Numerous epidemiological studies of lung cancer among textile workers worldwide consistently indicate reduced risks related to cotton dust exposure, presumably due to endotoxin contamination. Our objective was to investigate associations with other exposures potentially related to lung cancer, including wool and synthetic fibre dusts, formaldehyde, silica, dyes and metals, that have only been studied to a limited extent in the textile industry. METHODS: We conducted a case-cohort study nested within a cohort of 267,400 women textile workers in Shanghai, China. We compared work assignments and exposure histories of 628 incident lung cancer cases, diagnosed during 1989-1998, with those of a reference subcohort of 3188 workers. We reconstructed exposures with a job-exposure matrix developed specifically for textile factories. Cox proportional hazards modelling was applied to estimate age/smoking-adjusted relative risks (hazard ratios) and risk gradients associated with job assignments and specific agents other than cotton dust and endotoxin. RESULTS: No associations were observed for lung cancer with wool, silk or synthetic fibre dusts, or with most other agents. However, increased risks, although statistically imprecise, were noted for ≥ 10 years' exposures to silica (adjusted HR 3.5, 95% CI 1.0 to 13) and ≥ 10 years' exposures to formaldehyde (adjusted HR 2.1, 95% CI 0.4 to 11). CONCLUSIONS: Exposures to silica and formaldehyde, although not widespread among the cohort, may have increased lung cancer risk. Silica is an established human lung carcinogen, whereas there is only weak prior evidence supporting an association with formaldehyde. Both exposures warrant consideration as potential lung carcinogens in textile manufacturing.

Dust and chemical exposures, and miscarriage risk among women textile workers in Shanghai, China.

INTRODUCTION: To investigate possible associations between miscarriage and occupational exposures in the Shanghai textile industry. METHODS: A retrospective cohort study of miscarriages among 1752 women in the Shanghai textile industry was conducted. Reproductive history was self-reported by women and occupational work histories were collected from factory personnel records. Occupational exposures were assigned by linking work history information to an industry-specific job-exposure matrix informed by factory-specific textile process information and industrial hygiene assessments. Estimates of cotton dust and endotoxin exposure were also assigned. Odds ratios (OR) and 95% CI were estimated by multivariate logistic regression, with adjustment for age at pregnancy, educational level, smoking status of the woman and her spouse, use of alcohol, and woman's year of birth. RESULTS: An elevation in risk of a spontaneously aborted first pregnancy was associated with exposure to synthetic fibres (OR 1.89, 95% CI 1.20 to 3.00) and mixed synthetic and natural fibres (OR 3.31, 95% CI 1.30 to 8.42). No increased risks were observed for women working with solvents, nor were significant associations observed with quantitative cotton dust or endotoxin exposures. Associations were robust and similar when all pregnancies in a woman's reproductive history were considered. CONCLUSIONS: Occupational exposure to synthetic fibres may cause miscarriages, and this possibility should be the subject of further investigation.

Levels of systemic metal ions in patients with intramedullary nails.

BACKGROUND: It is being increasingly recognized that orthopedic implants are associated with adverse tissue responses, mediated by degradation products. Recent interest has been focused on the production of metal ions from hip arthroplasty. Few studies have reviewed fracture fixation devices and their metal ion production. METHODS: 61 subjects were enlisted into the study, with 3 subgroups. 21 subjects had Russell-Taylor intramedullary tibial nails in situ for 26 (21-32) months (316LVm stainless steel), 20 subjects had TriGen intramedullary tibial nails in situ for 43 (35-51) months (Ti-6Al-4V titanium alloy), and the remaining 20 subjects did not have any implant in situ and served as controls. Blood samples were taken and serum chromium, molybdenum, titanium, aluminium, and vanadium concentrations were measured using inductively coupled plasma (ICP) techniques. RESULTS: The 3 groups were matched for age, sex, and BMI. The subjects with Russell-Taylor nails had elevated levels of chromium (0.10 microg/L) with median concentrations 2.5 times higher than those of the control group. The subjects with TriGen nails had less significantly elevated levels of titanium (6.5 microg/L). INTERPRETATION: Stainless steel implants show significant differences from titanium implants in the dissemination of metal ions. Although the levels of chromium were elevated, the overall levels were modest when compared to published data regarding metal ion release and hip arthroplasty. Intramedullary nails are, however, often used in younger patients. If not removed, they may result in prolonged exposure to metal ions.

Acute inflammatory response does not affect erythrocyte concentrations of copper, zinc and selenium.

BACKGROUND & AIMS: Measuring the nutritional status of trace elements in plasma is invalidated in the presence of a systemic inflammatory response. We examined the potential of erythrocytes to assess copper, zinc and selenium status in such situations. METHODS: Venous blood samples were withdrawn pre-operatively and at 12, 24, 48, 72 and 168 h post-operatively from 11 patients (6 males and 5 females) who were admitted for elective knee arthroplasty. C-reactive protein, albumin, copper, zinc, selenium and iron were measured in plasma and erythrocytes. RESULTS: Plasma zinc and selenium concentrations fell significantly: 95% confidence intervals (CI)=-32% to -44% and -22% to -36%, respectively. Copper concentrations fell transiently and then increased significantly: CI=12-43%. No significant changes were seen in trace element concentrations in erythrocytes expressed either as a ratio of haemoglobin or iron concentration. Erythrocyte iron levels correlated significantly with haemoglobin (r=0.93). CONCLUSIONS: Plasma concentrations of copper, zinc and selenium are unreliable markers of status in patients with an acute inflammatory response. Erythrocyte concentrations of these trace elements may provide a more reliable measure in long-term studies of patients with a chronic systemic inflammatory response. Iron can be used instead of haemoglobin as the denominator when expressing erythrocyte concentrations of trace elements.

Occupational risk factors for pancreatic cancer among female textile workers in Shanghai, China.

OBJECTIVES: To investigate whether occupational exposures to dusts and chemicals in the Shanghai textile industry are associated with risk of pancreatic cancer. METHODS: A case cohort study nested in a cohort of 267,400 female textile workers in Shanghai, China was conducted among 180 incident pancreatic cancer cases and an age stratified randomly selected comparison subcohort (n = 3188). A complete occupational history of work in the textile industry was obtained for each woman, and was linked to a job exposure matrix developed for the textile industry to estimate exposures to specific dusts and chemicals. Cumulative exposures to cotton dust and endotoxin were reconstructed from historical and contemporaneous measurements. RESULTS: After adjusting for smoking status, a trend of decreasing risk of pancreatic cancer was observed for increasing cumulative exposures to cotton dust and endotoxin with a lag of 20 years. The hazard ratios for women cumulatively exposed to >143.4 mg/m3 x years of cotton dust and >3530.6 EU/m3 x years of endotoxin were 0.6 (95% CI 0.3 to 0.9) and 0.5 (95% CI 0.3 to 0.9), respectively, compared to unexposed women. There was little evidence that exposures to other textile dusts and chemicals were associated with risk of pancreatic cancer. CONCLUSIONS: Occupational exposure to cotton dust and endotoxin in the textile industry may have reduced risks of pancreatic cancer in this cohort. These associations should be replicated by others before making a firm conclusion of their possible effects on pancreatic cancer.

Clinical and pathologic characteristics of focal segmental glomerulosclerosis pathologic variants.

Histologic variants of idiopathic focal segmental glomerulosclerosis (FSGS) may have prognostic value. A recent working classification system has distinguished five FSGS variants. We evaluated a cohort of adult patients with biopsy-proven FSGS diagnosed between March 1982 and July 2001 to determine if subtypes were associated with renal outcome. Renal biopsies were reviewed by two pathologists. Demographic and clinical data were obtained from charts. Outcomes were partial and complete remission of the nephrotic syndrome, and renal failure. The frequency of FSGS variants was: 3% cellular (N=6), 11% collapsing (N=22), 17% tip lesion (N=34), 26% perihilar (N=52), and 42% not otherwise specified (NOS) (N=83). Collapsing FSGS affected younger and more often black patients. Black race was uncommon in tip variant. Collapsing and tip variants had higher proteinuria and lower serum albumin than perihilar and NOS variants. Better renal function and less severe tubulointerstitial injury were observed in patients with tip variant. These patients were more likely to receive steroids and more often achieved complete remission (50%). After a median follow-up of 1.8 years, 23% of patients were on dialysis and 28% had renal failure. Collapsing FSGS had worse 1-year (74%) and 3-year (33%) renal survival compared to other variants (overall cohort renal survival at 1 and 3 years: 86 and 67%). Different histologic variants of FSGS have substantial differences in clinical features at the time of biopsy diagnosis and substantial differences in renal outcomes.

Reproductive history, occupational exposures, and thyroid cancer risk among women textile workers in Shanghai, China.

OBJECTIVES: Thyroid cancer risk has been previously associated with increased age at first pregnancy and history of miscarriage. Occupational risk factors for thyroid cancer, with the exception of radioactive iodine, have not been well investigated. We conducted a case-cohort study nested in a cohort of 267,400 female textile workers in Shanghai, China, who had been followed for cancer incidence during 1989-1998. METHODS: The analysis included 130 incident thyroid cases and 3,187 subcohort non-cases. Reproductive history was determined by questionnaire at baseline. Historical exposures were reconstructed from work history and information on factory processes and exposures. Cox proportional hazards analysis was performed to estimate hazard ratios (HR) for reproductive factors and occupational exposures. RESULTS: Associations were observed between thyroid cancer and employment in jobs with 10 or more years of benzene exposure (HR 6.43, 95% CI: 1.08, 38) and formaldehyde exposure (HR 8.33, 95% CI: 1.16, 60). Administration workers also had an increased risk (HR 1.56, 95% CI: 1.08, 2.25). No associations between examined reproductive factors and thyroid cancer were observed in this study. CONCLUSIONS: Despite statistically imprecise risk estimates, the findings suggest potential associations with some occupational chemical exposures in this cohort of textile workers.

Occupational risk factors for nasopharyngeal cancer among female textile workers in Shanghai, China.

AIMS: To investigate whether occupational exposure to dusts and chemicals in the Chinese textile industry are associated with risk of nasopharyngeal cancer. METHODS: Sixty seven nasopharyngeal carcinoma (NPC) cases identified during 1989-98 and a random sample (n = 3188) of women were included in a case cohort study nested in a cohort of 267,400 women textile workers in Shanghai, China. A complete occupational history of work in the textile industry was obtained for each woman. A job exposure matrix developed by experienced industrial hygienists was used to assess exposures to specific dusts and chemicals. RESULTS: Risk of NPC is associated with cumulative exposure to cotton dust. The hazard ratio for women cumulatively exposed to >143.4 mg/m3 x years of cotton dust was 3.6 (95% CI 1.8 to 7.2) compared with unexposed women. Trends of increasing risk were also found with increasing duration of exposure to acids and caustics (p = 0.05), and with years worked in dyeing processes (p = 0.06). Women who worked at least 10 years in dyeing processes had a 3.6-fold excess risk of NPC (95% CI 1.0 to 12.1). CONCLUSIONS: Occupational exposure to cotton dust, acids, and caustics, and work in dyeing and printing jobs in the textile industry may have increased risk of NPC in this cohort.

Colorectal cancer incidence among female textile workers in Shanghai, China: a case-cohort analysis of occupational exposures.

Previous studies have suggested increased risks of colorectal cancers among textile industry workers, potentially related to synthetic fibers. To investigate risks of colon and rectum cancers in relation to these and other textile industry exposures, we conducted a case-cohort study nested within a cohort study of female employees from the Shanghai Textile Industry Bureau (STIB). Cox proportional hazard regression modeling was used to estimate hazard ratios (HR) for colon and rectum cancers associated with duration of employment (e.g., 0, >0 to <10, 10 to <20 years, > or =20 years) in various jobs classified according to process type and exposures to specific agents. Our findings indicate that certain long term exposures may pose increased risk of colorectal cancers, especially dyes and dye intermediates with colon cancer (> or =20 years exposure versus never, HR=3.9; 95% CI: 1.4-10.6), and maintenance occupation (HR = 2.3; 95% CI: 1.0-5.7) and metals exposure (HR = 2.0; 95% CI: 1.1-3.6) with rectum cancer. A decreased risk of rectum cancer was associated with exposure to natural fibers such as cotton (HR = 0.7; 95% CI: 0.5-0.9), and a trend of decreasing rectum cancer incidence was observed by category of cumulative quantitative cotton dust or endotoxin exposures, when exposures were lagged by 20 years.