Auranofin Induces Lethality Driven by Reactive Oxygen Species in High-Grade Serous Ovarian Cancer Cells

High-grade serous ovarian cancer (HGSOC) accounts for 70% of ovarian cancer cases, and the survival rate remains remarkably low due to the lack of effective long-term consolidation therapies. Clinical remission can be temporarily induced by platinum-based chemotherapy, but death subsequently results from the extensive growth of a platinum-resistant component of the tumor. This work explores a novel treatment against HGSOC using the gold complex auranofin (AF). AF primarily functions as a pro-oxidant by inhibiting thioredoxin reductase (TrxR), an antioxidant enzyme overexpressed in ovarian cancer. We investigated the effect of AF on TrxR activity and the various mechanisms of cytotoxicity using HGSOC cells that are clinically sensitive or resistant to platinum. In addition, we studied the interaction between AF and another pro-oxidant, L-buthionine sulfoximine (L-BSO), an anti-glutathione (GSH) compound. We demonstrated that AF potently inhibited TrxR activity and reduced the vitality and viability of HGSOC cells regardless of their sensitivities to platinum. We showed that AF induces the accumulation of reactive oxygen species (ROS), triggers the depolarization of the mitochondrial membrane, and kills HGSOC cells by inducing apoptosis. Notably, AF-induced cell death was abrogated by the ROS-scavenger N-acetyl cysteine (NAC). In addition, the lethality of AF was associated with the activation of caspases-3/7 and the generation of DNA damage, effects that were also prevented by the presence of NAC. Finally, when AF and L-BSO were combined, we observed synergistic lethality against HGSOC cells, which was mediated by a further increase in ROS and a decrease in the levels of the antioxidant GSH. In summary, our results support the concept that AF can be used alone or in combination with L-BSO to kill HGSOC cells regardless of their sensitivity to platinum, suggesting that the depletion of antioxidants is an efficient strategy to mitigate the course of this disease.

Home hemodialysis technique survival: insights and challenges

Home hemodialysis (HHD) offers several clinical, quality of life and cost-saving benefits for patients with end-stage kidney disease. While uptake of this modality has increased in recent years, its prevalence remains low and high rates of discontinuation remain a challenge. This comprehensive narrative review aims to better understand what is currently known about technique survival in HHD patients, elucidate the clinical factors that contribute to attrition and expand on possible strategies to prevent discontinuation. With increasing efforts to encourage home modalities, it is imperative to better understand technique survival and find strategies to help maintain patients on the home therapy of their choosing. It is crucial to better target high-risk patients, examine ideal training practices and identify practices that are potentially modifiable to improve technique survival.

"The Phone is my Lifeline": Use of Mobile Phone Technology to Support Recovery among Individuals in Treatment for Substance Use Disorders

Background: People experiencing substance use disorders (SUD) face myriad challenges in maintaining changes in substance use after treatment. Mobile phones can play a role in supporting the recovery process. To date, research has not explored how individuals use mobile phones to seek social support as they enter SUD recovery. Objectives: We sought to understand how individuals in SUD treatment use mobile technology in support of their recovery. Methods: We conducted semi-structured interviews with thirty individuals in treatment for any SUD in northeastern Georgia and southcentral Connecticut. Interviews explored participants' attitudes toward mobile technology and how they used mobile technology while using substances, in treatment, and in recovery. Qualitative data were coded and analyzed using thematic analysis. Results: We identified three major themes related to how participants: (1) adapted their use of mobile technology as they entered recovery, (2) relied on mobile technology for social support while in recovery, while (3) some found aspects of mobile technology triggering. Many individuals in SUD treatment reported using mobile phones to buy or sell drugs; as such, they took measures to adapt their use of mobile technology as they changed substance use behaviors. As they entered recovery, individuals relied on mobile phones for affiliational, emotional, informational, and instrumental support, though some did share they found some aspects of mobile phones triggering. Conclusion: These findings highlight the importance of treatment providers engaging in conversations around mobile phone use to help individuals avoid triggers and connect with social supports. These findings uncover new opportunities for recovery support interventions utilizing mobile phones as a delivery mechanism.

PATHOLOGIC FINDINGS IN GENDER-AFFIRMING MASTECTOMY: A SYSTEMATIC REVIEW

Following increased cultural awareness, expanded access to care, and decreased stigmatization, the number of transgender individuals seeking gender affirmation surgery such as gender-affirmation mastectomy (GAM) continues to rise. While post-mastectomy breast tissue is often sent for pathologic evaluation, few studies address the utility and standardization of this practice. This literature review evaluates the pathology findings in GAM specimens reported in the medical literature. A systematic review following PRISMA guidelines was performed to evaluate all medical publications related to pathology reports following GAM. The overall type and incidence of benign and malignant breast lesions were analyzed to elucidate which patient characteristics significantly affect the pathology findings. Overall, eight of 488 identified studies met inclusion criteria (1278 patients). The incidence of pre-malignant lesions was 2.42%, including flat epithelial atypia (0.08%), atypical hyperplasia (0.23%), atypical ductal hyperplasia (1.33%), atypical lobular hyperplasia (0.39%), and lobular carcinoma in situ (0.39%).Patient age, hormonal therapy, and family / patient history of breast cancer were inconsistently reported among included studies. Lack of standardized pathologic classification did not permit further statistical analysis. Although patients who undergo GAM are unlikely to have premalignant or malignant findings on breast pathology examination, pathologic evaluation of breast tissue remains common practice. Additional studies, which include a standardized method of pathologic evaluation, are necessary before practice guidelines can be recommended.

Impact of the abandonment of assistive technologies for mobility on the incidence of serious falls in older adults living at home: Results of the ECOCAT study

Purpose

To examine the impact of discontinuing the use of assistive technology for mobility (ATM) devices on the 6-months incidence of falls in older adults (OA) living at home.

Materials and methods

A medico-socioeconomic survey was performed to collect information on the quality of life and well-being of older adults, before and 6 months after being loaned an ATM device. Personal data (medical, social, and economic) were collected via a geriatric survey.

Results

In all, 102 OA participated in the study. Over the 6-months observation period, 17 (n = 81) serious falls were recorded among participants who were using their ATM device optimally; in those who discontinued device use, 12 falls (n = 21) were recorded (57.1%; p = 0.001). Factors significantly associated with falls at home were living in an urban area (odds ratio [OR]: 11.46; 95% confidence interval [CI]: 1.48; 88.98; p = 0.020), an Instrumental Activities of Daily Living Scale score > 4 (OR: 34.04; 95% CI: 1.59; 727.86; p = 0.024), and discontinuation of ATM device use (OR: 17.41; 95% CI: 2.59; 117.02; p = 0.003).

Conclusion

Discontinuation of ATM device use was associated with an increased risk for serious falls.

Comprehensive epigenomic profiling of human alveolar epithelial differentiation identifies key epigenetic states and transcription factor co-regulatory networks for maintenance of distal lung identity

Background

Disruption of alveolar epithelial cell (AEC) differentiation is implicated in distal lung diseases such as chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, and lung adenocarcinoma that impact morbidity and mortality worldwide. Elucidating underlying disease pathogenesis requires a mechanistic molecular understanding of AEC differentiation. Previous studies have focused on changes of individual transcription factors, and to date no study has comprehensively characterized the dynamic, global epigenomic alterations that facilitate this critical differentiation process in humans.

Results

We comprehensively profiled the epigenomic states of human AECs during type 2 to type 1-like cell differentiation, including the methylome and chromatin functional domains, and integrated this with transcriptome-wide RNA expression data. Enhancer regions were drastically altered during AEC differentiation. Transcription factor binding analysis within enhancer regions revealed diverse interactive networks with enrichment for many transcription factors, including NKX2–1 and FOXA family members, as well as transcription factors with less well characterized roles in AEC differentiation, such as members of the MEF2, TEAD, and AP1 families. Additionally, associations among transcription factors changed during differentiation, implicating a complex network of heterotrimeric complex switching in driving differentiation. Integration of AEC enhancer states with the catalog of enhancer elements in the Roadmap Epigenomics Mapping Consortium and Encyclopedia of DNA Elements (ENCODE) revealed that AECs have similar epigenomic structures to other profiled epithelial cell types, including human mammary epithelial cells (HMECs), with NKX2–1 serving as a distinguishing feature of distal lung differentiation.

Conclusions

Enhancer regions are hotspots of epigenomic alteration that regulate AEC differentiation. Furthermore, the differentiation process is regulated by dynamic networks of transcription factors acting in concert, rather than individually. These findings provide a roadmap for understanding the relationship between disruption of the epigenetic state during AEC differentiation and development of lung diseases that may be therapeutically amenable.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-08152-6.

Evaluation of a home-based 7-day infection control strategy for healthcare workers following high-risk exposure to severe acute respiratory coronavirus virus 2 (SARS-CoV-2): A cohort study

OBJECTIVE

Evidence-based infection control strategies are needed for healthcare workers (HCWs) following high-risk exposure to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). In this study, we evaluated the negative predictive value (NPV) of a home-based 7-day infection control strategy.

METHODS

HCWs advised by their infection control or occupational health officer to self-isolate due to a high-risk SARS-CoV-2 exposure were enrolled between May and October 2020. The strategy consisted of symptom-triggered nasopharyngeal SARS-CoV-2 RNA testing from day 0 to day 7 after exposure and standardized home-based nasopharyngeal swab and saliva testing on day 7. The NPV of this strategy was calculated for (1) clinical coronavirus disease 2019 (COVID-19) diagnosis from day 8-14 after exposure, and for (2) asymptomatic SARS-CoV-2 detected by standardized nasopharyngeal swab and saliva specimens collected at days 9, 10, and 14 after exposure. Interim results are reported in the context of a second wave threatening this essential workforce.

RESULTS

Among 30 HCWs enrolled, the mean age was 31 years (SD, ±9), and 24 (80%) were female. Moreover, 3 were diagnosed with COVID-19 by day 14 after exposure (secondary attack rate, 10.0%), and all cases were detected using the 7-day infection control strategy: the NPV for subsequent clinical COVID-19 or asymptomatic SARS-CoV-2 detection by day 14 was 100.0% (95% CI, 93.1%-100.0%).

CONCLUSIONS

Among HCWs with high-risk exposure to SARS-CoV-2, a home-based 7-day infection control strategy may have a high NPV for subsequent COVID-19 and asymptomatic SARS-CoV-2 detection. Ongoing data collection and data sharing are needed to improve the precision of the estimated NPV, and here we report interim results to inform infection control strategies in light of a second wave threatening this essential workforce.

The Spectrum of Clinical Characteristics and Complications of Tetanus: A Retrospective Cross-Sectional Study From a Developing Nation

Introduction While tetanus has largely been eradicated with the advent of the tetanus vaccine, its prevalence in Pakistan remains alarmingly high due to insufficient uptake of the vaccination program. The clinical presentations that the disease elicits range from mere opisthotonos to more sinister complications, including respiratory failure and death, often posing an insurmountable challenge for hospitals. Methods A retrospective cross-sectional study was conducted and analyzed the medical charts of 43 patients with a confirmed diagnosis of tetanus infection. The charts were perused for the patients' demographics, clinical characteristics, and disease outcomes. The prevalence of various clinical symptoms and complications were reported in terms of frequencies and percentages. Results The mean age of the patients hovered at 29.53 ± 16.53 years, with a range of 12 to 65 years. Of those affected, 83.7% were males while 16.3% were females. Notably, none of the infected patients had a prior history of vaccination against tetanus. Trismus was noted to be the most prevalent clinical manifestation and was found in 90.70% of the patients while paraesthesia at the site of infection, found in 6.98%, was the least prevalent. The overall mortality was noted to hover at 46.5%. Conclusion While tetanus has largely been eradicated, its prevalence in Pakistan remains alarmingly high. The complications noted in the study have implications for the country's public health system and aims to better inform the current state of the national vaccination program.

Coronavirus Disease 2019 Presenting as Abdominal Distension in a Mesothelioma Patient: Do We Need to Think Outside the Box?

The coronavirus disease 2019 (COVID-19) remains a major source of mortality globally. Although it usually presents with flu-like symptoms such as fever and sore throat, the intensity of the symptoms varies, constituting a spectrum ranging from asymptomatic to severe cases of acute respiratory failure. The highest proportion of severe cases occurs in older individuals and in those who have underlying health conditions and chronic comorbidities. We chronicle an atypical case of a 46-year-old male with stage IV mesothelioma who presented exclusively with complaints of acute abdominal pain and distension. Despite his cancer status, the patient’s respiratory functions remained unremarkable, accentuating the peculiarity of the case.

A256 TRENDS IN THE PREVALENCE AND SEVERITY OF ANEMIA IN PEDIATRIC PATIENTS WITH INFLAMMATORY BOWEL DISEASE IN THE LAST DECADE

Background

Anemia is one of the most common extraintestinal manifestations in patients with inflammatory bowel disease (IBD) at diagnosis. Studies have shown that anemia was associated with low levels of quality of life, which improves with the correction of anemia in adults. Recent data have shown an increase in the incidence and severity of pediatric IBD.

Aims

To investigate the prevalence of anemia in children at diagnosis of IBD and the trends in the past decade. The secondary aim was to investigate the associations between hemoglobin (Hb) levels and disease characteristics.

Methods

Eligible patients (age ≤18 years, diagnosed with IBD from 2009 to 2018) were retrospectively identified through our IBD database. Disease localization and phenotype were defined according to the Paris Classification of IBD. Anemia was defined by Hb levels according to WHO targets. The annual prevalence of anemia was calculated according to subtype (inflammatory vs iron deficiency). The Pediatric Crohn’s Disease Activity Index (PCDAI) and the Pediatric Ulcerative Colitis Activity Index (PUCAI) were used to assess the disease severity at diagnosis.

Results

We included 887 patients (439 females), mean (SD) age of 13.1 (3.4) years. Of these, 519 (58.5%) were identified with anemia within 30 days of diagnosis. The median (IQR) Hb level was 108 (98 -114) g/dL. Severe anemia (< 70 g/dL) was present in 1.8 % of patients. The prevalence of anemia at diagnosis remained relatively stable ranging from 60.2% in 2009 to 60.4% in 2018. The annual proportion of inflammatory vs iron-deficiency anemia is displayed in figure 1. Anemia was more prevalent in Crohn’s disease (CD) (62.2%) than Ulcerative colitis (UC) (57.9%) or IBD-unclassified (39.6%). The disease severity scores were higher in those with anemia. The median (IQR) PCDAI and PUCAI were respectively 37.5 (27.5–47.5) and 55.0 (40.0–65.0) in the anemic group as compared to 27.5 (20.0–37.50) and 35.0 (25.0–55.0) in the non-anemic group; P<0.0001. Patients with anemia had a lower BMI z-score [median (IQR) -0.84 (-1.84 - 0.08)] than the non-anemic patients [median (IQR) -0.38 (-1.21 - 0.43)]; P<0.001. The prevalence of anemia correlated significantly with disease location: upper intestinal involvement [L4a(67.7%) L4b(63.6%) L4aL4b(60.7%) none (52.8%)] P = 0.024 for CD; for UC [E1(21.1%) E2(44.4%) E3(75.0%) E4 (71.1%)] P<0.0001. A moderate correlation was found between Hb levels and C-reactive protein (r= -0.312, 95% CI: -0.378 to -0.243, P<0.0001).

Conclusions

Anemia remains a prevalent symptom in pediatric patients with IBD, and it is correlated with the extent of intestinal involvement and disease severity. The impact of anemia at Diagnosis and during follow-up on the levels of quality of life and physical activity is currently under investigation.

Funding Agencies

None

Psychiatric and physical outcomes of long-term use of lithium in older adults with bipolar disorder and major depressive disorder: A cross-sectional multicenter study

OBJECTIVE

Although lithium is widely used in current practice to treat bipolar disorder (BD) and treatment-resistant major depressive disorder (MDD) among older adults, little is known about its efficacy and tolerability in this population, which is generally excluded from randomized clinical trials. The objective of this study was to evaluate the efficacy and tolerability of long-term use of lithium among older adults with BD and MDD.

METHOD

Data from the Cohort of individuals with Schizophrenia and mood disorders Aged 55 years or more (CSA) were used. Two groups of patients with BD and MDD were compared: those who were currently receiving lithium versus those who were not. The effects of lithium on psychiatric (i.e., depressive symptoms severity, perceived clinical severity, rates of psychiatric admissions in the past-year), geriatric (overall and cognitive functioning) and physical outcomes (i.e., rates of non-psychiatric medical comorbidities and general hospital admissions in the past-year) were evaluated. All analyses were adjusted for age, sex, duration of disorder, diagnosis, smoking status, alcohol use, and use of antipsychotics, antiepileptics or antidepressants.

RESULTS

Among the 281 older participants with BD or MDD, 15.7% were taking lithium for a mean duration of 12.5(SD = 11.6) years. Lithium use was associated with lower intensity of depressive symptoms, reduced perceived clinical global severity and lower benzodiazepine use (all p < 0.05), without being linked to greater rates of medical comorbidities, except for hypothyroidism.

LIMITATIONS

Data were cross-sectional and data on lifetime history of psychotropic medications was not assessed.

CONCLUSION

Our results suggest that long-term lithium use may be efficient and relatively well-tolerated in older adults with BD or treatment-resistant MDD.

Clinical Pharmacogenetics Implementation Consortium guidelines for HLA-B genotype and carbamazepine dosing

Human leukocyte antigen B (HLA-B) is a gene that encodes a cell surface protein involved in presenting antigens to the immune system. The variant allele HLA-B*15:02 is associated with an increased risk of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) in response to carbamazepine treatment. We summarize evidence from the published literature supporting this association and provide recommendations for the use of carbamazepine based on HLA-B genotype (also available on PharmGKB: http://www.pharmgkb.org). The purpose of this article is to provide information to allow the interpretation of clinical HLA-B*15:02 genotype tests so that the results can be used to guide the use of carbamazepine. The guideline provides recommendations for the use of carbamazepine when HLA-B*15:02 genotype results are available. Detailed guidelines regarding the selection of alternative therapies, the use of phenotypic tests, when to conduct genotype testing, and cost-effectiveness analyses are beyond the scope of this document. Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines are published and updated periodically on the PharmGKB website at (http://www.pharmgkb.org).

[Acute myocardial infarction and MRI: a comparison of infarct size by MRI and peak creatine kinase after a first episode]

AIM

To compare the assessment of infarct size using MRI and peak CK value.

POPULATION AND METHODS

16 patients presenting with a first MI and seriall measurement of CK underwent gadolinium-enhanced MRI.

RESULTS

A significant correlation was observed between both estimates of infarct size (r=0.56, p=0.0025). In addition, an inverse correlation was found between residual viability and peak CK (r=-0.51; p=0.043).

CONCLUSION

After a first episode of MI, infarct size estimate by MRI correlates with that determined by peak CK measurement.

Extracellular signal-regulated kinase induces cyclin D1 and Cdk-2 expression and phosphorylation of retinoblastoma in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies in Southeast Asia. Hyperphosphorylation of retinoblastoma (pRB) by cyclin/CDKs in G1/S transition is required for its inactivation and cell cycle progression. In the present study, we report that phosphorylation of pRB at Ser780 and Ser795 was detected in 71% (33 of 46) and 63% (29 of 46) of HCCs examined respectively. pRB protein was undetectable in 13% (6 of 46) of HCCs examined. Phosphorylated pRB was localized in the nuclei of hepatocarcinoma cells. Benign hepatocytes exhibited very weakly or no nuclear staining for phosphorylated pRB. Over-expression of E2F-1, cyclin D1, Cdk-2, Cdk-4 and cyclin A was found in 64% (30 of 46), 43% (26 of 46), 28% (11 of 46), 71% (33 of 46) and 63% (29 of 46) of HCCs examined respectively and this was correlated with elevation of ERK. Treatment of HepG2 cells with MEK1/2 inhibitor U0126 resulted in cell cycle arrest, downregulation of cyclin D1 and Cdk-2 expression and inhibition of pRB phosphorylation at Ser780 and Ser795. Ectopic expression of activated MEK1 in HepG2 cells increased cyclin D1 and Cdk-2 expression, phosphorylation of pRB at Ser780 and Ser795, and percentage of cells in S phase. Our data indicate that activated ERK plays an important role in cyclin D1 and Cdk-2 expression and phosphorylation of pRB at Ser780 and Ser795 in liver cancer cells.

Electron exchange between two electrodes mediated by two electroactive adsorbates

Experimental data for electron exchange between two electrodes covered by electroactive films are presented and discussed in terms of the Gerischer model. A model Hamiltonian is proposed for such indirect electron exchange involving two intermediate species. Explicit model calculations are performed for the case in which the coupling between the two adsorbates is weak and determines the overall rate. The calculations agree well with the experimental data, and can be used to determine the energy of reorganization associated with the electron transfer.

The role of activated MEK-ERK pathway in quercetin-induced growth inhibition and apoptosis in A549 lung cancer cells

Dietary phytochemicals have been shown to be protective against various types of cancers. However, the precise underlying protective mechanisms are poorly understood. In the present study, we report that treatment of A549 cells with quercetin resulted in a dose-dependent reduction in cell viability and DNA synthesis with the rate of apoptosis equivalent to 1.2 +/- 0.8, 6.3 +/- 0.9, 16.5 +/- 1.5, 36.4 +/- 2.6 and 42.5 +/- 5.8% on treatment with 0.1% dimethylsulfoxide, 14.5, 29.0, 43.5 and 58.0 micro M quercetin, respectively. Concomitantly, quercetin treatments led to a 1.1-, 1.1-, 2.5- and 3.5-fold increase in Bax. Similar elevations were also observed in Bad, which increased 1.1-, 2.1-, 2.2- and 2.3-fold, respectively, as compared with control. While Bcl-2 was decreased by 30%, Bcl-x(L) was elevated in a dose-dependent fashion. Quercetin also induced the cleavage of caspase-3, caspase-7 and PARP (poly ADP-ribose polymerase). While Akt-1 and phosphorylated Akt-1 were inhibited, the extracellular signal-regulated kinase (ERK) was phosphorylated following quercetin treatment in a dose-dependent fashion. Phosphorylation of ERK and c-Jun occurred at 3 h and was sustained over 14 h. Phosphorylation of MEK1/2 was increased in concordance with ERK activation. Quercetin-induced phosphorylation of c-Jun N-terminal kinase (JNK) and cleavage of caspase-3 occurred 6 h after quercetin exposure and before cleavage of caspase-7 and PARP was detected. Inhibition of MEK1/2 but not PI-3 kinase, p38 kinase or JNK abolished quercetin-induced phosphorylation of c-Jun, cleavage of caspase-3 and -7, cleavage of PARP and apoptosis. Inhibition of caspase activation completely blocked quercetin-induced apoptosis. Expression of constitutively activated MEK1 in A549 cells led to activation of caspase-3 and apoptosis. The results suggest that in addition to inactivation of Akt-1 and alteration in the expression of the Bcl-2 family of proteins, activation of MEK-ERK is required for quercetin-induced apoptosis in A549 lung carcinoma cells.

Kaempferol-induced growth inhibition and apoptosis in A549 lung cancer cells is mediated by activation of MEK-MAPK

A vast variety of naturally occurring substances have been shown to protect against experimental carcinogenesis and an increasing amount of evidence suggests that kaempferol may have cancer chemopreventative properties. However, the precise underlying protective mechanisms are poorly understood. To elucidate these mechanisms, we challenged human lung cancer cell line A549 with kaempferol and investigated its effects upon cellular growth and signal transduction pathways. Treatment of A549 cells with kaempferol resulted in a dose- and time-dependent reduction in cell viability and DNA synthesis with the rate of apoptosis equivalent to 0.9+/-0.5, 5.2+/-1.5, 16.8+/-2.0, 25.4+/-2.6, and 37.8+/-4.5% on treatment with 0, 17.5, 35.0, 52.5, and 70.0 microM kaempferol, respectively. Concomitantly, kaempferol treatments led to a 1.2-, 2.7-, 3.3-, and 3.4-fold increase in Bax. Similar elevations were also observed in Bad which increased 1.2-, 3.3-, 3.7-, and 4.7-fold, respectively, as compared to control. Bcl-2 and Bcl-xL expression were inhibited in a dose-dependent fashion. While the Akt-1 and phosphorylated Akt-1 were inhibited, the mitogen-activated protein kinase (MAPK) was activated upon kaempferol treatment. Kaempferol induced apoptosis was associated with the cleavage of caspase-7 and poly ADP-ribose polymerase (PARP). Inhibition of MEK1/2 but not PI-3 kinase blocked kaempferol-induced cleavage of caspase-7, PARP cleavage, and apoptosis. The results suggest that inactivation of Akt-1 and alteration of Bcl-2 family of proteins are not sufficient for kaempferol to induce apoptosis and activation of MEK-MAPK is a requirement for kaempferol-induced cell death machinery in A549 cells.

Suppression of insulin-like growth factor signalling pathway and collagen expression in keloid-derived fibroblasts by quercetin: its therapeutic potential use in the treatment and/or prevention of keloids

BACKGROUND

Keloids are characterized by abnormal proliferation of fibroblasts and overproduction of collagen. Insulin-like growth factor (IGF)-I is mitogenic for fibroblasts and a stimulatory factor for collagen synthesis.

OBJECTIVES

We have assessed the in vitro effects of quercetin on proliferation, collagen synthesis and the expression of the IGF system in keloid-derived fibroblasts.

METHODS

Fibroblasts were isolated from earlobe keloids and exposed to quercetin at different concentrations. The inhibitory effects of quercetin on fibroblast proliferation were assayed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Western and Northern blot analyses.

RESULTS

Quercetin inhibited keloid fibroblast (KF) proliferation in a dose-dependent manner. Significant growth inhibition was observed on day 2 of culture. The dose required for 50% growth inhibition was approximately 25 microg mL-1. Collagen 1 expression was significantly decreased while collagen 3 was almost undetectable following quercetin treatment. Basal levels of IGF-I receptor (IGF-IR) beta subunits, p85 subunit of phosphatidylinositol 3-kinase, c-Raf, phospho-Raf-1, phospho-MEK 1/2, phospho-mitogen-activated protein kinase, phospho-Elk-1 and phospho-Akt-1 were significantly reduced when KF cells were exposed to quercetin for 24 h. Blocking IGF-IR activity with IGF-IR antibody or neutralizing endogenous IGF-I activity with IGF-I antibody led to significant growth inhibition suggesting the role of IGF-I in regulation of KF proliferation.

CONCLUSIONS

Because the IGF system plays an important part in fibroblast cell proliferation and collagen production, the described activities of quercetin on the IGF system and collagen expression may provide a novel approach for the use of quercetin in treatment and/or prevention of hypertrophic scar and keloid.

Induction of UO-44 gene expression by tamoxifen in the rat uterus and ovary

A complementary DNA, uterine-ovarian-specific gene 44 (UO-44), has been isolated from tamoxifen-induced rat uterine complementary DNA library using differential display techniques. UO-44 transcripts are found to be abundant in the uterus and ovary. UO-44 gene expression in the uterus is strictly regulated by estrogens, tamoxifen, and GH, whereas the pure antiestrogen ICI 182780 is inhibitory. Treatment of ovariectomized rats and hypophysectomized rats with tamoxifen and GH, respectively, resulted in up-regulation of UO-44 expression in a dose-dependent manner. In situ hybridization revealed that UO-44 gene expression was restricted to the luminal and glandular epithelial cells of the uterus and to granulosa cells of medium-size ovarian follicles. Transfection studies showed that UO-44 was a membrane-associated protein. Because estrogens, tamoxifen, and GH are stimulators of uterine luminal epithelial cell growth in vivo, UO-44 protein may serve as a mediator of the effect of these compounds in inducing epithelial proliferation and differentiation in these tissues.

Induction of apoptosis in mammary gland by a pure anti-estrogen ICI 182780

The antiestrogen, ICI 182780 (ICI) proves to be clinically useful for the treatment of estrogen receptor positive breast tumours. We report the assessment of the in vivo and in vitro effects of ICI on apoptosis of breast epithelial cells. In vivo, administration of rats with ICI for 3 weeks resulted in a reduction in the size of the lobular structures with the rate of mammary epithelial apoptosis equivalent to 10, 35 and 45% on treatment with 1, 1.5 and 2 mg ICI per kg body weight, respectively. Concomitantly, these treatment led to a 2.0-, 2.2- and 2.5-fold increase in Bax. Similar elevations were also observed in Bad levels which increased 1.7-, 2.6- and 2.7-fold respectively in the ICI treatment as compared to controls. This also resulted in a dose dependent decrease in Bcl-2 and Bcl-xL protein expressions. Growth inhibition and induction of apoptosis were also observed in the MCF-7 cells following in vitro treatment with ICI. This is closely associated with [1] the down-regulation of Bcl-2 and Bcl-xL proteins and [2] upregulation of Bax and Bad, whose gene products are known to be involved the regulation of apoptosis in mammalian cells. Stable over-expression of Bcl-2 resulted in protection of MCF-7 cells from apoptosis and growth inhibitory effects of ICI. Conversely, reduction of Bcl-2 by antisense transfection make MCF-7 cells more sensitive to ICI-induced growth inhibition and apoptosis. These findings suggest that modulation of Bax, Bcl-xL, Bcl-2 and Bad proteins by ICI may be, in part, responsible for the anti-proliferative and apoptotic effect of ICI seen clinically and in animal models.

Thermal activation of hydrocarbon C-H bonds by tungsten alkylidene complexes

Thermal activation of CpW(NO)(CH(2)CMe(3))(2) (1) in neat hydrocarbon solutions transiently generates the neopentylidene complex, CpW(NO)(=CHCMe(3)) (A), which subsequently activates solvent C-H bonds. For example, the thermolysis of 1 in tetramethylsilane and perdeuteriotetramethylsilane results in the clean formation of CpW(NO)(CH(2)CMe(3))(CH(2)SiMe(3)) (2) and CpW(NO)(CHDCMe(3))[CD(2)Si(CD(3))(3)] (2-d(12)), respectively, in virtually quantitative yields. The neopentylidene intermediate A can be trapped by PMe(3) to obtain CpW(NO)(=CHCMe(3))(PMe(3)) in two isomeric forms (4a-b), and in benzene, 1 cleanly forms the phenyl complex CpW(NO)(CH(2)CMe(3))(C(6)H(5)) (5). Kinetic and mechanistic studies indicate that the C-H activation chemistry derived from 1 proceeds through two distinct steps, namely, (1) rate-determining intramolecular alpha-H elimination of neopentane from 1 to form A and (2) 1,2-cis addition of a substrate C-H bond across the W=C linkage in A. The thermolysis of 1 in cyclohexane in the presence of PMe(3) yields 4a-b as well as the olefin complex CpW(NO)(eta(2)-cyclohexene)(PMe(3)) (6). In contrast, methylcyclohexane and ethylcyclohexane afford principally the allyl hydride complexes CpW(NO)(eta(3)-C(7)H(11))(H) (7a-b) and CpW(NO)(eta(3)-C(8)H(13))(H) (8a-b), respectively, under identical experimental conditions. The thermolysis of 1 in toluene affords a surprisingly complex mixture of six products. The two major products are the neopentyl aryl complexes, CpW(NO)(CH(2)CMe(3))(C(6)H(4)-3-Me) (9a) and CpW(NO)(CH(2)CMe(3))(C(6)H(4)-4-Me) (9b), in approximately 47 and 33% yields. Of the other four products, one is the aryl isomer of 9a-b, namely, CpW(NO)(CH(2)CMe(3))(C(6)H(4)-2-Me) (9c) ( approximately 1%). The remaining three products all arise from the incorporation of two molecules of toluene; namely, CpW(NO)(CH(2)C(6)H(5))(C(6)H(4)-3-Me) (11a; approximately 12%), CpW(NO)(CH(2)C(6)H(5))(C(6)H(4)-4-Me) (11b; approximately 6%), and CpW(NO)(CH(2)C(6)H(5))(2) (10; approximately 1%). It has been demonstrated that the formation of complexes 10 and 11a-b involves the transient formation of CpW(NO)(CH(2)CMe(3))(CH(2)C(6)H(5)) (12), the product of toluene activation at the methyl position, which reductively eliminates neopentane to generate the C-H activating benzylidene complex CpW(NO)(=CHC(6)H(5)) (B). Consistently, the thermolysis of independently prepared 12 in benzene and benzene-d(6) affords CpW(NO)(CH(2)C(6)H(5))(C(6)H(5)) (13) and CpW(NO)(CHDC(6)H(5))(C(6)D(5)) (13-d(6)), respectively, in addition to free neopentane. Intermediate B can also be trapped by PMe(3) to obtain the adducts CpW(NO)(=CHC(6)H(5))(PMe(3)) (14a-b) in two rotameric forms. From their reactions with toluene, it can be deduced that both alkylidene intermediates A and B exhibit a preference for activating the stronger aryl sp(2) C-H bonds. The C-H activating ability of B also encompasses aliphatic substrates as well as it reacts with tetramethylsilane and cyclohexanes in a manner similar to that summarized above for A. All new complexes have been characterized by conventional spectroscopic methods, and the solid-state molecular structures of 4a, 6, 7a, 8a, and 14a have been established by X-ray diffraction methods.

Flow-cytometric method for the quantitation of the Fc function of intravenous immunoglobulin preparations

OBJECTIVES

We have developed and optimised a new flow-cytometric method for the measurement of the Fc function of intravenous immunoglobulin (IVIg) preparations, which is important in predicting the effector function of immunoglobulin (Ig) in such preparations.

MATERIALS AND METHODS

Ig was bound to a monocytic cell line, THP-1 with Fc gammaRI and Fc gammaRII cell surface receptors, and the bound Ig detected by FITC-conjugated F(ab)2 fragment of rabbit anti-human IgG.

RESULTS

Validation studies showed that Ig bound to the cell line through the Fc portion. The method detected alterations in Fc function caused by reduction with dithiothreitol or by storage. The method was reproducible (CV<11%) and a limited comparison study showed that it correlated with the European Pharmacopoeia reference method.

CONCLUSIONS

This technically simple method is suitable for the quantitation of the Fc function of Ig preparations.

Interferon-gamma in progression to chronic demyelination and neurological deficit following acute EAE

The cytokine interferon-gamma (IFNgamma) is implicated in the induction of acute CNS inflammation, but it is less clear what role if any IFNgamma plays in progression to chronic demyelination and neurological deficit. To address this issue, we have expressed IFNgamma in myelinating oligodendrocytes of transgenic mice. MHC I immunostaining and iNOS mRNA were upregulated in their CNS, but such transgenic mice showed no spontaneous CNS inflammation or demyelination, and the incidence, severity, and histopathology of experimental autoimmune encephalomyelitis (EAE) were similar to nontransgenic controls. In contrast to control mice, which remit from EAE with resolution of glial reactivity and leukocytic infiltration, transgenics showed chronic neurological deficits. While activated microglia/macrophages persisted in demyelinating lesions for over 100 days, CD4(+) T lymphocytes were no longer present in CNS. IFNgamma therefore may play a role in chronic demyelination and long-term disability following the induction of demyelinating disease. Because IFNgamma may have neural as well as immune-infiltrating origins, these findings generate a new perspective on its role in the CNS.

Immune cell entry to the CNS--a focus for immunoregulation of EAE

T-cell-derived cytokines are therefore individually unnecessary and collectively insufficient for microglial response. This somewhat provocative interpretation does not exclude a role for T-cell cytokines in induction of a microglial response in EAE, but it may be easier to show a non-requirement then to prove such a role. The point that emerges is that cytokine production in the CNS parenchyma is itself dependent on the prior infiltration of immune cells, and that without immune cell entry, EAE does not occur. This identifies events at the BBB, and in particular in the perivascular space, as critical immunoregulatory events in development and progression of EAE.

Biological activity of von Willebrand factor during the manufacture of therapeutic factor VIII concentrates as determined by the collagen-binding assay

In this study the use of collagen-binding assay, recently recommended by the European Pharmacopoeia for the characterization of Factor VIII/von Willebrand Factor (FVIII/vWF) concentrates was investigated. The collagen-binding assay was optimized to decrease reagent variability and, to allow for interlaboratory comparison, standardized against the third WHO International Plasma Standard for vWF and factor VIII, with the assumption that 1 unit of vWF antigen = 1 unit of collagen binding activity. A study of clinical samples of patients with von Willebrand's disease established that a ratio of vWF antigen; Collagen-binding activity <1.4 was associated with normal multimeric distribution and a ratio >3.7 was associated with loss of high molecular weight multimers and a decrease in biological activity. The collagen-binding assay of vWF was used to monitor changes in the biological activity of vWF during the manufacture of FVIII concentrates. Two commonly used industrial procedures using either glycine/NaCl precipitation or ion exchanges with TSK DEAE column chromatography were investigated. Samples taken at individual stages in the purification of FVIII concentrates, at the laboratory and industrial scale, were monitored using FVIII coagulant activity:vWF antigen ratio, Collagen-binding activity:vWF antigen ratio, and sodium dodecyl sulfate-agarose vWF multimeric analysis. All three parameters showed a retention of multimeric structure and biological activity during manufacture, to yield products which were clinically relevant in the treatment of von Willebrand's diseases.

Glutamate metabolism is down-regulated in astrocytes during experimental allergic encephalomyelitis

Experimental allergic encephalomyelitis (EAE) was induced in SJL/J mice by adoptive transfer of MBP-reactive T cells in order to investigate the role of astrocytes in pathology. GFAP protein and mRNA expression (analyzed using semiquantitative Western blot and RT-PCR techniques) were upregulated in the spinal cord of mice, which had developed a complete paralysis of hind- and fore-limbs and tail (grade 4 EAE), thus establishing that reactive gliosis occurred under these experimental conditions. Within the same samples and using similar techniques, we found that glutamine synthetase (GS) and glutamate dehydrogenase (GDH) expression were dramatically reduced. These two astrocytic enzymes are responsible for degradation of glutamate, the most abundant excitatory neurotransmitter in the brain. Since elevated levels of glutamate may be neurotoxic, we propose that the decreased capacity of astrocytes to metabolize glutamate may contribute to EAE pathology.