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China currently has the highest acid deposition globally, yet research on its status, impacts, causes and controls is lacking. Here, we compiled data and calculated critical loads regarding acid deposition. The results showed that the abatement measures in China have achieved a sharp decline in the emissions of acidifying pollutants and a continuous recovery of precipitation pH, despite the drastic growth in the economy and energy consumption. However, the risk of ecological acidification and eutrophication showed no significant decrease. With similar emission reductions, the decline in areas at risk of acidification in China (7.0%) lags behind those in Europe (20%) or the USA (15%). This was because, unlike Europe and the USA, China's abatement strategies primarily target air quality improvement rather than mitigating ecological impacts. Given that the area with the risk of eutrophication induced by nitrogen deposition remained at 13% of the country even under the scenario of achieving the dual targets of air quality and carbon dioxide mitigation in 2035, we explored an enhanced ammonia abatement pathway. With a further 27% reduction in ammonia by 2035, China could largely eliminate the impacts of acid deposition. This research serves as a valuable reference for China's future acid deposition control and for other nations facing similar challenges. [ABSTRACT FROM AUTHOR]

Background: A better definition of biomarkers and biological processes related to local recurrence and disease progression is highly warranted for ductal breast carcinoma in situ (DCIS). Stromal-epithelial interactions are likely of major importance for the biological, clinical, and pathological distinctions between high- and low-risk DCIS cases.Methods: Stromal platelet derived growth factor receptor (PDGFR) was immunohistochemically assessed in two DCIS patient cohorts (n = 458 and n = 80). Cox proportional hazards models were used to calculate the hazard ratios of recurrence. The molecular mechanisms regulating stromal PDGFR expression were investigated in experimental in vitro co-culture systems of DCIS cells and fibroblasts and analyzed using immunoblot and quantitative real-time PCR. Knock-out of JAG1 in DCIS cells and NOTCH2 in fibroblasts was obtained through CRISPR/Cas9. Experimental data were validated by mammary fat pad injection of DCIS and DCIS-JAG1 knock-out cells (10 mice per group). All statistical tests were two-sided.Results: PDGFRα(low)/PDGFRβ(high) fibroblasts were associated with increased risk for recurrence in DCIS (univariate hazard ratio = 1.59, 95% confidence interval [CI] = 1.02 to 2.46; P = .04 Wald test; multivariable hazard ratio = 1.78, 95% CI = 1.07 to 2.97; P = .03). Tissue culture and mouse model studies indicated that this fibroblast phenotype is induced by DCIS cells in a cell contact-dependent manner. Epithelial Jagged1 and fibroblast Notch2 were identified through loss-of-function studies as key juxtacrine signaling components driving the formation of the poor prognosis-associated fibroblast phenotype.Conclusions: A PDGFRα(low)/PDGFRβ(high) fibroblast subset was identified as a marker for high-risk DCIS. The Jagged-1/Notch2/PDGFR stroma-epithelial pathway was described as a novel signaling mechanism regulating this poor prognosis-associated fibroblast subset. In general terms, the study highlights epithelial-stromal crosstalk in DCIS and contributes to ongoing efforts to define clinically relevant fibroblast subsets and their etiology. [ABSTRACT FROM AUTHOR]

Background. The kinetics of hepatitis B surface antigen (HBsAg) are predictive in HBV-infected patients treated with pegylated interferon. Knowledge about the value of HBsAg levels in patients coinfected with HBV and human immunodeficiency virus (HIV) is lacking.Methods. We quantified serum HBsAg in a Dutch multicenter cohort of 104 patients coinfected with HIV and HBV who were treated with tenofovir disoproxil fumarate (TDF) as part of highly active antiretroviral therapy. The median duration of therapy was 57 months (interquartile range, 34–72 months).Results. Hepatitis B e antigen (HBeAg)–positive patients achieved a decline of 2.2 log IU/mL in HBsAg, whereas HBeAg-negative patients only achieved a decline of 0.6 log IU/mL during 6 years of TDF therapy. Declines in HBsAg at months 6 and 12 correlated with CD4 cell count for HBeAg-positive patients. Five HBeAg-positive patients (8%) and 3 HBeAg-negative patients (8%) cleared HBsAg. HBeAg-negative patients who cleared HBsAg had lower baseline HBsAg as compared to patients who remained HBsAg positive. The majority of patients who cleared HBsAg achieved this end point within the first year. In HBeAg-positive patients, decline in HBsAg at month 6 was predictive of achieving HBsAg seroclearance.Conclusions. Receipt of TDF therapy by HIV/HBV-coinfected patients for up to 6 years led to a significant decrease in HBsAg in the HBeAg-positive population. HBsAg kinetics early during treatment were predictive of HBsAg seroclearance and correlated with an increased CD4 cell count, underlining the importance of immune restoration in HBV clearance. [ABSTRACT FROM PUBLISHER]

Objectives Plasma concentrations are frequently used for therapeutic drug monitoring of antiretroviral drugs. Dried blood spot sampling offers a patient-friendly and easy alternative to plasma sampling. However, dried blood spot concentrations are not necessarily equal to plasma concentrations and therefore the objective of this work was to establish the relationship between nevirapine and efavirenz dried blood spot and plasma concentrations to facilitate clinical implementation of dried blood spot sampling. Methods Paired dried blood spot and plasma samples were obtained from 40 HIV-infected patients on nevirapine and 40 on efavirenz treatment. All samples were analysed using validated HPLC–tandem mass spectrometry methods for the two matrices. Theoretical plasma concentrations were calculated from dried blood spot concentrations using the formula [dried blood spot concentration/(1 − haematocrit)] × fraction bound to plasma proteins = plasma concentration. Linear regression and Bland–Altman analysis were used to compare the two methods. Results Dried blood spot and plasma concentrations of nevirapine and efavirenz correlated well (r2 = 0.867 and 0.972, respectively), although efavirenz dried blood spot concentrations were 39.8% (SD 7.1%) lower than plasma concentrations. Theoretical plasma concentrations (using patient-specific haematocrit) of nevirapine and efavirenz were similar to measured plasma concentrations, with a mean difference between the two methods of 0.29 mg/L (SD 1.35 mg/L) and 0.08 mg/L (SD 0.31 mg/L), respectively. Conclusions Dried blood spot concentrations of nevirapine and efavirenz were equal to plasma concentrations after correction for haematocrit and compound-specific plasma protein binding and can therefore be used in clinical practice. [ABSTRACT FROM PUBLISHER]

Retrograde messengers adjust the precise timing of neurotransmitter release from the presynapse, thus modulating synaptic efficacy and neuronal activity. 2-Arachidonoyl glycerol, an endocannabinoid, is one such messenger produced in the postsynapse that inhibits neurotransmitter release upon activating presynaptic CB1 cannabinoid receptors. Cognitive decline in Alzheimer’s disease is due to synaptic failure in hippocampal neuronal networks. We hypothesized that errant retrograde 2-arachidonoyl glycerol signalling impairs synaptic neurotransmission in Alzheimer’s disease. Comparative protein profiling and quantitative morphometry showed that overall CB1 cannabinoid receptor protein levels in the hippocampi of patients with Alzheimer’s disease remain unchanged relative to age-matched controls, and CB1 cannabinoid receptor-positive presynapses engulf amyloid-β-containing senile plaques. Hippocampal protein concentrations for the sn-1-diacylglycerol lipase α and β isoforms, synthesizing 2-arachidonoyl glycerol, significantly increased in definite Alzheimer’s (Braak stage VI), with ectopic sn-1-diacylglycerol lipase β expression found in microglia accumulating near senile plaques and apposing CB1 cannabinoid receptor-positive presynapses. We found that microglia, expressing two 2-arachidonoyl glycerol-degrading enzymes, serine hydrolase α/β-hydrolase domain-containing 6 and monoacylglycerol lipase, begin to surround senile plaques in probable Alzheimer’s disease (Braak stage III). However, Alzheimer’s pathology differentially impacts serine hydrolase α/β-hydrolase domain-containing 6 and monoacylglycerol lipase in hippocampal neurons: serine hydrolase α/β-hydrolase domain-containing 6 expression ceases in neurofibrillary tangle-bearing pyramidal cells. In contrast, pyramidal cells containing hyperphosphorylated tau retain monoacylglycerol lipase expression, although at levels significantly lower than in neurons lacking neurofibrillary pathology. Here, monoacylglycerol lipase accumulates in CB1 cannabinoid receptor-positive presynapses. Subcellular fractionation revealed impaired monoacylglycerol lipase recruitment to biological membranes in post-mortem Alzheimer’s tissues, suggesting that disease progression slows the termination of 2-arachidonoyl glycerol signalling. We have experimentally confirmed that altered 2-arachidonoyl glycerol signalling could contribute to synapse silencing in Alzheimer’s disease by demonstrating significantly prolonged depolarization-induced suppression of inhibition when superfusing mouse hippocampi with amyloid-β. We propose that the temporal dynamics and cellular specificity of molecular rearrangements impairing 2-arachidonoyl glycerol availability and actions may differ from those of anandamide. Thus, enhanced endocannabinoid signalling, particularly around senile plaques, can exacerbate synaptic failure in Alzheimer’s disease. [ABSTRACT FROM AUTHOR]

We retrospectively screened 1836 men who have sex with men (MSM) participating in the Amsterdam Cohort Studies (1984-2003) for hepatitis C virus (HCV) antibodies. HCV incidence was 0.18/100 person-years (PY) in human immunodeficiency virus (HIV)-positive MSM (8/4408 PY [95% confidence interval {CI}, 0.08-0.36]) but was 0/100 PY in MSM without HIV (0/7807 PY [95% CI, 0.00-0.05]). After 2000, HCV incidence among HIV-positive men increased 10-fold to 0.87/100 PY (5/572 PY [95% CI, 0.28-2.03]). Additional hospital cases (n = 34) showed that MSM in Amsterdam who acquired HCV infection after 2000 reported high rates of ulcerative sexually transmitted infections (59%) and rough sexual techniques (56%), denied injection drug use, and were infected mainly with the difficult-to-treat HCV genotypes 1 (56%) and 4 (36%). Phylogenetic analysis showed 3 monophyletic clusters of MSM-specific HCV strains. The emergence of an MSM-specific transmission network suggests that HIV-positive MSM with high-risk sexual behaviors are at risk for sexually acquired HCV. Targeted prevention and routine HCV screening among HIV-positive MSM is needed to deter the spread of HCV. [ABSTRACT FROM AUTHOR]

There is little information about the risk of treatment failure after a switch from human immunodeficiency virus (HIV) protease inhibitors (PIs) to nevirapine (Nvp) for patients with successful virus suppression. This study compared the 1-year risk of treatment failure for patients switching from a first PI-containing antiretroviral regimen to Nvp (Nvp group) with the risk for patients switching to second-line PIs (PI group) in the ATHENA (AIDS Therapy Evaluation, The Netherlands) study cohort (n = 2470) whose HIV-1 RNA loads were ≤ 500 copies/mL. Treatment failure was defined as measurement of HIV-1 RNA loads > 500 twice or > 10,000 copies/mL once or discontinuation of treatment for any reason. There were 446 eligible patients, 125 in the Nvp group and 321 in the PI group. The risk of treatment failure in the Nvp group, after data were adjusted for other risk factors, was 5-fold (95 % confidence interval, 0.1-0.4) lower than the risk in the PI group, primarily because the discontinuation rate was lower. In patients with virus suppression, a switch to Nvp is more likely than a switch to second-line PIs to result in sustained virus suppression and maintenance of the new regimen. [ABSTRACT FROM AUTHOR]

An AIDS patient with the recalcitrant erythematous desquamating (RED) disorder, a presumed variant of the Staphylococcus aureus toxic shock syndrome that is characterized by relapses, skin involvement, and variable multiple-organ involvement, is described. A strain of S. aureus producing toxic shock syndrome toxin 1 was isolated from the patient, but no antibodies to this exotoxin were detectable before and during the most severe episode of the RED disorder. Levels of cytokines were measured during episodes and at other times. Tumor necrosis factor and interleukin 6 were detectable only during the most severe exacerbation of the disorder; this finding suggests a pathogenetic role for these cytokines. [ABSTRACT FROM PUBLISHER]

The aim of this study was to estimate the prevalence of depressive symptoms and depressive disorder (ICHPPC-2-defined) in patients over 65 years of age. A cross-sectional, partly two-phased, study was performed in general practices in The Netherlands. A total of 384 consecutive patients aged 65 and above, 116 men and 265 women were included, both during practice visits and home visits. Depressive symptoms were recorded with the Zung Self-rating Depression Scale, the Geriatric Depression Scale, and with physician ratings. Assessments of depressive disorder were based on an adaptation of interview ratings with the Montgomery Åsberg Depression Rating Scale. The proportion of patients considered to have depressive symptoms ranged from 11 to 29% of patients, depending on the self-report instrument and the cut-off point. According to interviews a depressive disorder was estimated to be present in 17%. The high prevalence of depressive symptoms and depressive disorder suggest a higher index of suspicion of depres sion in elderly general practice patients. [ABSTRACT FROM PUBLISHER]

A randomized controlled study was done to determine whether initial combination therapy with zidovudine and zalcitabine or zidovudine and didanosine would delay the emergence of zidovudineresistant virus. Human immunodeficiency virus (HIV)-1-infected patients with <300 CD4 cells/mm3 and <4 weeks of prior zidovudine therapy were randomized to zidovudine, zidovudine plus zalcitabine, or zidovudine plus didanosine. Combination therapy did not delay the emergence of zidovudine-resistant virus isolates. However, combination therapy resulted in a significant increase in CD4 cells through 72 weeks compared with zidovudine monotherapy and a greater and more sustained decline in serum HIV-1 RNA. Although this trial was not designed as a clinical end-point study, patients assigned to zidovudine plus didanosine combination therapy experienced a significant delay in time to first AIDS-defining event or death compared with those assigned to zidovudine monotherapy. [ABSTRACT FROM PUBLISHER]

Serum concentrations of soluble receptors for tumor necrosis factor-α (sTNFαR) types I and II, β2-microglobulin, and CD4 cell counts were determined at entry and 3–5 months before AIDS diagnosis in 20 untreated, asymptomatic human immunodeficiency virus type 1 (HIV-1)-seropositive subjects, who progressed to AIDS within 5.5 years of study entry, and in an equal number of HIV-seronegative and untreated seropositive controls, who remained asymptomatic. At entry, concentrations of sTNFαR type II and β2-microglobulin were elevated and increased further in progressors. The odds ratio (OR) for sTNFaR type II concentrations ⩾6.5 ng/ml, was 18.4 and for β2-microglobulin concentrations ⩾3 mg/L was 6.6; CD4 cell counts were not predictive. Five months before diagnosis, the OR was 102.0 for sTNFaR type II concentrations ⩾7.5 ng/ml., 13.5 for β2-microglobulin concentrations ⩾4 mg/L, and 6.9 for CD4 cell counts <250/mm3 (counts >500/mm3 were not predictive). Ofthe three variables, sTNFαR type II was proved by bivariate analysis to be the strongest and earliest predictor of disease progression. [ABSTRACT FROM PUBLISHER]

The effect of zidovudine on disease progression in asymptomatic human immunodeficiency virus type 1 (HIV-2)-infected men (n = 52) in relation to CD4 T cell numbers, T cell reactivity, and HIV-1 biologic phenotype was studied in a double-blind randomized trial over 2 years. CD4+ cell numbers and T cell reactivity did not differ significantly between the zidovudine- and placebo- treated groups, except for a transient improvement of both parameters in the zidovudinetreated group during the first 9 months. A marked differential efficacy of zidovudine was observed depending on the HIV-1 phenotype present. Zidovudine did not prevent the emergence of high-replicating syncytium-inducing (SI) variants, and clinical progression was observed in persons with SI variants despite zidovudine treatment. In contrast to nontreated HIV-I-infected asymptomatic persons, zidovudine-treated men who did not develop SI variants did not progress to AIDS. The beneficial effect of zidovudine during the asymptomatic phase may be mainly limited to persons who do not develop SI variants in the course of HIV-1 infection. [ABSTRACT FROM PUBLISHER]

The steroid hormone dehydroepiandrosterone (DHEA) has been reported to protect against certain viral infections in animal models and to be a modest inhibitor of human immunodeficiency virus type 1 (HIV-1) infection in vitro. Serum DHEA levels were determined in 41 asymptomatic HIV-1-seropositive subjects, who progressed to AIDS within 5 years after entering a cohort study, in 41 HIV-1-seropositive controls, who remained asymptomatic, and in 41 HIV-1 seronegative controls. At entry, DHEA levels were higher in the seronegative group (median, 13.3 nmol/I) than in either the seropositive nonprogressors (median, 9.2 nmol/l; P = .01) or the progressors (median, 7.2 nmol/l; P < .001). DHEA levels in the progressors ∼5 months before the diagnosis of AIDS were lower than the levels in the nonprogressors after the same follow-up (median, 5.6 vs. 8.8 nmol/l; P = .007). DHEA levels <7 nmol/l and CD4+ cell counts <0.5 × 109/l both proved to be independent predictors for disease progression in HIV-1-infected men. [ABSTRACT FROM PUBLISHER]

The order of appearance in the reverse transcriptase gene of four mutations implicated in the development of resistance to zidovudine was investigated by selective polymerase chain reaction. Serial human immunodeficiency virus isolates were studied from 18 initially asymptomatic individuals who had been treated with zidovudine for 2 years. Most subjects had similar patterns. The first mutation occurred transiently at codon 70; its disappearance was paralleled by the appearance of a mutation at codon 215. Subsequently, in some individuals, the mutation at codon 70 reappeared. During the 2 years of treatment, no mutations developed at codon 219 and only one at codon 67, suggesting that most individuals developed only partly resistant virus. This was confirmed by plaque-reduction assay. Six subjects progressed to AIDS within the 2-year study period, confirming that the development of highly resistant isolates is not required for progression in treated individuals. No clear temporal relationship was found between the development of partial resistance and progression. [ABSTRACT FROM AUTHOR]

Definitions of ‘language’ are often lacking in theoretical as well as practical value. A noteworthy exception is Martinet's statement about the ‘double articulation’ of language. The way inwhich the ‘double articulation’ is described in linguistic text-books, however, is inconsistent with the Saussurian concept of a ‘sign’, and it leads to contradictions. If we change the interpretation slightly, without affecting the intended value of the definition, the contradictions are removed, and a clear parallelism between ‘phonology’ and ‘grammar’ is revealed. As a result, the relevant concepts, both in phonology and grammar, gain considerably in clarity and exactitude. [ABSTRACT FROM PUBLISHER]

We describe a drug-drug interaction between coformulated lopinavir/ritonavir and itraconazole in a patient infected with human immunodeficiency virus type 1 who had disseminated histoplasmosis. Coadministration of these agents led to a strong increase in itraconazole concentrations and a decrease in concentrations of its metabolite, hydroxyitraconazole, which is equally active pharmacologically. The dosage of itraconazole was reduced when it was used in combination with lopinavir/ritonavir. [ABSTRACT FROM AUTHOR]