All-polysaccharide, self-healing, pH-sensitive, in situ-forming hydrogel of carboxymethyl chitosan and aldehyde-functionalized hydroxyethyl cellulose

In situ forming hydrogels are promising for biomedical applications, especially in drug delivery. The precursor solution can be injected at the target site, where it undergoes a sol-gel transition to afford a hydrogel. In this sense, the most significant characteristic of these hydrogels is fast gelation behavior after injection. This study describes an all-polysaccharide, rapidly in situ-forming hydrogel composed of carboxymethyl chitosan (CMCHT) and hydroxyethyl cellulose functionalized with aldehyde groups (HEC-Ald). The HEC-Ald was synthesized through acetal functionalization, followed by acid deprotection. This innovative approach avoids cleavage of pyran rings, as is inherent in the periodate oxidation approach, which is the most common method currently employed for adding aldehyde groups to polysaccharides. The resulting hydrogel exhibited fast stress relaxation, self-healing properties, and pH sensitivity, which allowed it to control the release of an encapsulated model drug in response to the medium pH. Based on the collected data, the HEC-Ald/CMCHT hydrogels show promise as pH-sensitive drug carriers.

4-Nitrochalcone as a potential drug in non-clinical breast cancer studies

Breast cancer is a high-magnitude public health problem, continually challenging physicians and scientists worldwide in the field of drug therapy. 4-nitrochalcone (4NC) is a phenolic compound that has promising antitumor activity in vitro, but its application in breast cancer treatment is still poorly explored. This study aimed to evaluate the action of 4NC in vitro and in vivo breast cancer models. The cytotoxic potential of 4NC was tested towards MCF-7 and MDA-MD-231 breast cancer cells, with a lower impact in the non-tumor lineage HB4a. For in vivo studies, solid Ehrlich carcinoma (SEC) was used, a syngeneic mouse model with non-nuclear estrogen and progesterone positivity, characterized by immunohistochemistry. Daily oral administration of 4NC (25 mg kg-1) for 21 days led to a consistent reduction in tumor growth compared to the vehicle group. No signs of toxicity evaluated by hematological, biochemical, histological, and oxidative stress parameters were observed in mice, and the DL50 was >2000 mg kg-1. The effectors Raptor and S6K1 showed decreased activation, with a consequent reduction in protein synthesis; concomitantly, there was an increase in LC3-II levels, but the protective autophagic response was not completed, with the maintenance of p62 levels and cell death. These results open new possibilities for the use of 4NC as a tumor cell metabolism modulating agent.

Dulaglutide as a demethylating agent to improve the outcome of breast cancer

Background: Dulaglutide emerged as a promising therapeutic option for diabetes mellitus Type 2 (DM2). Aims: Owing to epigenetic similarities between the pathophysiology of DM2 and breast cancer (BC), we investigated the antitumor effect of dulaglutide. Materials & methods: To investigate the effect of dulaglutide, we analyzed the expression of methylated gene promoter regions in BC (ESR1, CDH1 and ADAM33). Results: Dulaglutide increased the expression of ESR1, CDH1 and ADAM33 up to fourfold in the MDA-MB-231 lineage by demethylating the gene promoter regions. This effect was translated to in vivo antitumoral activity and revealed significant tumor inhibition by combining the half-dose of methotrexate with dulaglutide. Conclusion: This therapy may mitigate the severe side effects commonly associated with chemotherapy.

Towards epigenetic regulation of triple-negative breast cancer via ligand-mediated nanoparticles

Aims: Develop and analyze triple-negative breast cancer targeted nanoparticles loaded with the demethylating agent decitabine. Materials & methods: The polymers were synthesized by ring-opening polymerization of D,l-lactide and formulated into nanoparticles via emulsion-evaporation method. The nanoparticles were characterized by physicochemical analysis as well as in vitro using breast cancer cell lineages. Results & conclusion: The targeted nanoparticles exhibited a hydrodynamic diameter of 75 ± 12 nm, zeta potential -6.3 ± 0.2 mV and spherical morphology, and displayed greater in vitro accumulation into MDA-MB-231 (triple-negative breast cancer cell-line) compared with MCF7 and HB4A cell lineages as verified by fluorescence confocal microscopy and significant demethylating effects via ADAM33 screening by PCR.

l-carvone decreases breast cancer cells adhesion, migration, and invasion by suppressing FAK activation

Breast cancer is one of the most common types of cancer in the world and current therapeutic strategies present severe drawbacks. l-carvone (CRV), a monoterpene found in Mentha spicata (spearmint), has been reported to have potent anti-inflammatory activity. Here, we examined the role of CRV in breast cancer cell adhesion, migration and invasion in vitro and how this component could suppress the growth of Ehrlich carcinoma-bearing mice. In vivo, treatment with CRV significantly decreased tumor growth, increased tumor necrosis area, and reduced the expression of VEGF and HIF-1α in Ehrlich carcinoma-bearing mice. Furthermore, the anticancer efficacy of CRV was similar to currently used chemotherapy (Methotrexate), and the combination of CRV with MTX potentiated the chemotherapy effects. Further mechanistic investigation in vitro revealed that CRV modulates the interaction of breast cancer cells with the extracellular matrix (ECM) by disrupting focal adhesion, which was shown by scanning electron microscopy (SEM) and immunofluorescence. Moreover, CRV caused a decrease in β₁-integrin expression and inhibited focal adhesion kinase (FAK) activation. FAK is one of the most important downstream activators of several metastatic processes, including MMP-2 mediated invasion and HIF-1α/VEGF angiogenesis stimulus, both of which were found to be reduced in MDA-MB-231 cells exposed to CRV. Our results provide new insight about targeting β₁-integrin/FAK signaling pathway with CRV, which could be a new potential agent in the treatment of breast cancer.

Chemical characterization and antineoplastic effect of oligosaccharides from Cabernet Franc red wine in mammary tumor model in mice

The present study characterized oligosaccharide compounds (Oligo) in Cabernet Franc red wine and investigated its antineoplastic effects against mammary tumor cells in vivo and in vitro, isolated or in combination with chemotherapy. The Oligo fraction was characterized by nuclear magnetic resonance spectroscopy and mass spectrometry. The complex mixture of Oligo showed high amounts of oligoxyloglucuronans, oligorhamnogalacturonans, oligoarabinogalactans, and oligoglucans, such as trehalose and isomaltotriose. To investigate the antineoplastic effects of Oligo, Female Swiss mice were subcutaneously inoculated with Ehrlich tumor cells and then received vehicle (distilled water, p.o.), Oligo solution (9, 35, or 70 mg/kg, p.o.), or methotrexate (1.5 mg/kg, i.p.). The treatments were administered in a conventional (21-d) or chemopreventive (42-d) protocol. Oligo reduced the growth of Ehrlich tumors in both protocols and increased the effectiveness of methotrexate in controlling tumor growth. Oligo did not reduce the viability of MCF-7, MDA-MB-231, MDA-MB-436, and HB4a human breast cells that were cultured for 48 h, showing no cytotoxicity. Overall, Oligo exerted an in vivo antineoplastic effect and modulated immune blood cells, dependent on treatment time, and was not directly cytotoxic to tumor cells. Thus, Oligo may indirectly regulate tumor cell development and may be a promising drug for cancer therapy in combination with methotrexate.

Ligand-mediated nanomedicines against breast cancer: a review

Ligand-mediated targeting represents the cutting edge in precision-guided therapy for several diseases. Surface engineering of nanomedicines with ligands exhibiting selective or tailored affinity for overexpressed biomolecules of a specific disease may increase therapeutic efficiency and reduce side effects and recurrence. This review focuses on newly developed approaches and strategies to improve treatment and overcome the mechanisms associated with breast cancer resistance.

Antitumoral activity of liraglutide, a new DNMT inhibitor in breast cancer cells in vitro and in vivo

Breast cancer (BC) is the most frequently diagnosed female cancer and second leading cause of death. Despite the discovery of many antineoplastic drugs for BC, the current therapy is not totally efficient. In this study, we investigated the potential of repurposing the well-known diabetes type II drug liraglutide to modulate epigenetic modifications in BC cells lines in vitro and in vivo via Ehrlich mice tumors models. The in vitro results revealed a significant reduction on cell viability, migration, DNMT activity and displayed lower levels of global DNA methylation in BC cell lines after liraglutide treatment. The interaction between liraglutide and the DNMT enzymes resulted in a decrease profile of DNA methylation for the CDH1, ESR1 and ADAM33 gene promoter regions and, consequently, increased their gene and protein expression levels. To elucidate the possible interaction between liraglutide and the DNMT1 protein, we performed an in silico study that indicates liraglutide binding in the catalytic cleft via hydrogen bonds and salt bridges with the interdomain contacts and disturbs the overall enzyme conformation. The in vivo study was also able to reveal that liraglutide and the combined treatment of liraglutide and paclitaxel or methotrexate were effective in reducing tumor growth. Moreover, the modulation of CDH1 and ADAM33 mouse gene expression by DNA demethylation suggests a role for liraglutide in DNMT activity in vivo. Altogether, these results indicate that liraglutide may be further analysed as a new adjuvant treatment for BC.

Polysaccharides from green sweet pepper increase the antineoplastic effect of methotrexate on mammary tumor cells

This study investigated the antineoplastic effects and toxicity of long-term treatment with polysaccharides from sweet green pepper (Capsicum annuum [CAP]), and concomitant treatment with CAP + methotrexate (MTX) on mammary tumor cells in vivo and in vitro. Ehrlich tumor cells were subcutaneously inoculated in female Swiss mice. The long-term treatment (31 days) with CAP (100 mg kg-1, p.o.) reduced the tumor growth and did not induce toxicity. The combined treatment protocol of 100 mg kg-1 CAP (p.o.) + 1 mg kg-1 MTX (i.p.) for 21 days inhibited the tumor growth in 95%, higher than the inhibition induced by MTX alone (1.0 or 2.5 mg kg-1, i.p.). In tumors, both CAP and CAP + MTX decreased the gene expression of Vegf, vessel area, and IL-4 and IL-10 levels, and increased IL-6 levels and the degree of necrosis. Treatment with CAP + MTX also increased TNF-α levels in tumors. Additionally, CAP + MTX treatment reduced the viability of human MDA-MB-231 and MDA-MB-436 mammary tumor cells in culture. In fact, CAP exerted antineoplastic effects in vivo and in vitro against mammary tumor cells, possibly by modulating inflammation and angiogenesis. CAP may be a promising adjunct chemotherapy with lower toxicity.

Salvia lachnostachys Benth has antitumor and chemopreventive effects against solid Ehrlich carcinoma

Salvia lachnostachys is an herbaceous plant with anti-inflammatory, analgesic and cytotoxic properties. This study investigated the antitumor effect of an ethanolic extract of Salvia lachnostachys leaves (EES) in a solid Ehrlich carcinoma model. Ehrlich cells were inoculated subcutaneously in the right pelvic member (2 × 10⁶ cells) in female Swiss mice. The animals were treated with vehicle (10 mL kg^-1, p.o.), EES (30 and 100 mg kg^-1, p.o.), or methotrexate (2.5 mg kg^-1, i.p.) for 21 days (early treatment) or 14 days (late treatment) after tumor inoculation, or 10 days before tumor inoculation and continued for 21 days after tumor inoculation (chemopreventive treatment). The acute toxicity test was performed according OECD guidelines Late treatment with EES had no antitumor effect. Early treatment with 100 mg kg^-1 EES prevented tumor development, increased tumor necrosis factor-α (TNF-α) levels and decreased tumor superoxide dismutase (SOD) activity, interleukin-10 (IL-10) levels and Cyclin D1 expression, and tumor cell necrosis was observed. Chemopreventive treatment with EES for 10 and 31 days prevented tumor development in the same manner. EES treatment for 31 days decreased hepatic and tumor SOD activity, tumor IL-10 levels and Cyclin D1 expression, and increased tumor reduced glutathione, N-acetylglucosaminidase, reactive oxygen species, lipid peroxidation, TNF-α levels and Nrf2 expression. No toxicity was observed in the acute toxicity assay. In conclusion, EES had an antitumor effect by inhibiting Cyclin D1 expression and increasing inflammation with early and chemopreventive treatment. Modulation of the antioxidant system also contribute for the antitumor effects of EES.

Antineoplastic effect of pectic polysaccharides from green sweet pepper (Capsicum annuum) on mammary tumor cells in vivo and in vitro

The present study investigated the antineoplastic effects of pectic polysaccharides that were extracted from green sweet pepper (Capsicum annuum [CAP]) in the Ehrlich carcinoma in mice and in human mammary tumor lineages. After the subcutaneous inoculation of 2 × 10⁶ Ehrlich tumor cells, Female Swiss mice received 50, 100, or 150 mg/kg CAP or vehicle orally once daily or methotrexate (2.5 mg/kg, i.p., every 5 days) for 21 days. CAP dose-dependently reduced Ehrlich tumor growth. It also reduced the viability of MCF-7, MDA-MB-231, and MDA-MB-436 human mammary cell lineages. Treatment with CAP reduced the gene expression of vascular endothelial growth factor in vivo and in vitro, reduced vessel areas of the tumors, and induced necrosis in Ehrlich solid tumors. CAP treatment significantly increased Interleukin-6 in tumors. The antineoplastic effect of CAP appears to depend on the regulation of inflammation and angiogenesis. Further studies are encouraged to better understand the CAP potential for the treatment of breast tumors.

DNA Methylation Status of the Estrogen Receptor α Gene in Canine Mammary Tumors

Estrogen receptor α (ERα) has an important role in mammary carcinogenesis, prognosis, and treatment. In human and canine mammary cancer, the most aggressive tumors show loss of ERα expression, which in human breast cancer has been attributed to methylation of the cytosine followed by guanine (CpG) island within the estrogen receptor α gene ( ESR1) promoter. This study aimed to investigate the role of ESR1 CpG island (CGI) methylation in ERα expression in canine mammary tumors. Twenty-one canine mammary samples were sorted into three groups: malignant tumor (n = 9), benign tumor (n = 8), and normal gland (n = 4). Immunohistochemical analysis and reverse-transcription quantitative real-time PCR were performed to assess ERα expression and ESR1 mRNA levels. The methylation status was determined using sodium-bisulfite-treated DNA sequencing. All normal mammary glands and benign tumors showed high ERα expression (score range, 5-8). Six of the nine malignant tumors did not show ERα expression (score 0), two had score 2, and one had score 4. Lower ERα ( P < .005) and ESR1 mRNA levels ( P < .005) were found in malignant mammary tumors than in the other two groups. Canine ESR1 has an intragenic and non-promoter-associated CGI, different from humans. No significant variation in methylation percentage was observed among the groups, suggesting that ESR1 is not regulated by DNA methylation, unlike that in humans. This difference should be considered in further research using ERα as a biomarker for mammary tumors in canine studies on ERα-targeting therapy.

MMP9 gene expression regulation by intragenic epigenetic modifications in breast cancer

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among women worldwide. Metastasis remains a major challenge for the clinical management and prognosis of patients with cancer. The metalloprotease MMP-9 plays a critical role in the first step of metastasis through extracellular matrix degradation. In this study, our goal was to determine the effect of epigenetic mechanisms in the promoter and intragenic region of this gene and to correlate it to the levels of expression of MMP9 in breast cancer cell lines. We have identified that MMP9 was highly expressed in the breast cancer cell lines MCF7 and MDA-MB-436 after 5-aza-2'-deoxycytidine (5-azadC) treatment. Sequencing of the promoter region as well as the CGI intronic CpG islands showed a specific sequence in CGI2, between CpGs 12-30 that was demethylated after 5-azadC treatment. This specific region was studied in breast cancer samples that revealed similar results with demethylation in positive MMP-9 breast cancer samples. Furthermore, the histone methylation marker of open chromatin (H3K4me3) was found in the promoter and intronic regions of MMP9 after 5-azadC treatment. Taken together these results showed a mechanism of DNA methylation and gene expression regulation by epigenetic marks present in the intronic DNA region of MMP9.

Ruthenium complex exerts antineoplastic effects that are mediated by oxidative stress without inducing toxicity in Walker-256 tumor-bearing rats

The present study evaluated the in vivo antitumor effects and toxicity of a new Ru(II) compound, cis-(Ru[phen]₂[ImH]₂)²⁺ (also called RuphenImH [RuC]), against Walker-256 carcinosarcoma in rats. After subcutaneous inoculation of Walker-256 cells in the right pelvic limb, male Wistar rats received 5 or 10mgkg^-1 RuC orally or intraperitoneally (i.p.) every 3 days for 13 days. A positive control group (2mgkg^-1 cisplatin) and negative control group (vehicle) were also used. Tumor progression was checked daily. After treatment, tumor weight, plasma biochemistry, hematology, oxidative stress, histology, and tumor cell respiration were evaluated. RuC was effective against tumors when administered i.p. but not orally. The highest i.p. dose of RuC (10mgkg^-1) significantly reduced tumor volume and weight, induced oxidative stress in tumor tissue, reduced the respiration of tumor cells, and induced necrosis but did not induce apoptosis in the tumor. No clinical signs of toxicity or death were observed in tumor-bearing or healthy rats that were treated with RuC. These results suggest that RuC has antitumor activity through the modulation of oxidative stress and impairment of oxidative phosphorylation, thus promoting Walker-256 cell death without causing systemic toxicity. These effects make RuC a promising anticancer drug for clinical evaluation.

Worse prognosis in breast cancer patients can be predicted by immunohistochemical analysis of positive MMP-2 and negative estrogen and progesterone receptors

Introduction:

Breast cancer is the most cause of death, and approximately 90% of these deaths are due to metastases. Matrix metalloproteinase-2 (MMP-2) gelatinase activity is able to degrade a major constituent of the tumor microenvironment, type IV collagen. Two well-established proteins used as markers in clinical practice for breast cancer are the receptors for estrogen (ER) and progesterone (PR). Although the presence of these receptors has been associated with a better prognosis, loss of these proteins can occur during tumor progression, with subsequent resistance to hormone therapy.

Objective:

To study the correlation among MMP-2, ER, and PR, as well as the establishment of the metastatic process in primary breast tumors.

Method:

Breast cancer samples (n=44) were analyzed by immunohistochemistry for MMP-2, ER, and PR.

Results:

We observed that 90% of patients who had metastases and died showed positive staining for MMP-2 (p=0.0082 for both). Using Kaplan-Meier analysis, we found that negative ER patients who were also positive for MMP-2 had even worse disease-free survival (DFS) and overall survival (OS) (p= 0.012 and p=0.005, respectively). Similar results were found in PR-negative patients for DFS (a trend p=0.077) and OS (p=0.038).

Conclusion:

Regardless of our small sample size (n=44), the data obtained strongly suggest that MMP-2 in combination with already well-established markers could help to predict the emergence of metastases and death in patients with breast cancer.

Down regulation of ADAM33 as a Predictive Biomarker of Aggressive Breast Cancer

Breast cancer is a heterogeneous disease with differences in its clinical, molecular and biological features. Traditionally, immunohistochemical markers together with clinicopathologic parameters are used to classify breast cancer and to predict disease outcome. Triple-negative breast cancer (TNBC) is a particular type of breast cancer that is defined by a lack of expression of hormonal receptors and the HER2 gene. Most cases of TNBC also have a basal-like phenotype (BLBC) with expression of cytokeratin 5/6 and/or EGFR. A basal marker alone is insufficient for a better understanding of the tumor biology of TNBC. In that regard, the ADAM33 gene is silenced by DNA hypermethylation in breast cancer, which suggests that ADAM33 might be useful as a molecular marker. In the present study, we have produced monoclonal antibodies against the ADAM33 protein and have investigated the role of ADAM33 protein in breast cancer. We used 212 breast tumor samples and lower levels of ADAM33 were correlated with TNBC and basal-like markers. A lower level of ADAM33 was also correlated with shorter overall survival and metastasis-free survival and was considered an independent prognostic factor suggesting that ADAM33 is a novel molecular biomarker of TNBC and BLBC that might be useful as a prognostic factor.

Necroptosis mediates the antineoplastic effects of the soluble fraction of polysaccharide from red wine in Walker-256 tumor-bearing rats

Polysaccharides are substances that modify the biological response to several stressors. The present study investigated the antitumor activity of the soluble fraction of polysaccharides (SFP), extracted from cabernet franc red wine, in Walker-256 tumor-bearing rats. The monosaccharide composition had a complex mixture, suggesting the presence of arabinoglactans, mannans, and pectins. Treatment with SFP (30 and 60mg/kg, oral) for 14days significantly reduced the tumor weight and volume compared with controls. Treatment with 60mg/kg SFP reduced blood monocytes and neutrophils, reduced the tumor activity of N-acetylglucosaminidase, myeloperoxidase, and nitric oxide, increased blood lymphocytes, and increased the levels of tumor necrosis factor α (TNF-α) in tumor tissue. Treatment with SFP also induced the expression of the cell necroptosis-related genes Rip1 and Rip3. The antineoplastic effect of SFP appears to be attributable to its action on the immune system by controlling the tumor microenvironment and stimulating TNF-α production, which may trigger the necroptosis pathway.

The GCKR Gene Polymorphism rs780094 is a Risk Factor for Gestational Diabetes in a Brazilian Population

BACKGROUND

The glucokinase regulatory protein (GCKR) regulates the activity of the glucokinase (GCK), which plays a key role in glucose homeostasis. Genetic variants in GCK have been associated with diabetes and gestational diabetes (GDM). Due to the relationship between GCKRP and GCK, polymorphisms in GCKR are also candidates for genetic association with GDM. The aim of this study was to evaluate the association between the GCKR rs780094 polymorphism and GDM in a Brazilian population.

METHODS

252 unrelated Euro-Brazilian pregnant women were classified as control (healthy pregnant women, n = 125) and GDM (pregnant women with GDM, n = 127) age-matched groups. Clinical and anthropometric data were obtained from all subjects. The GCKR rs780094 polymorphism was genotyped using fluorescent probes (TaqMan^® , code C_2862873_10).

RESULTS

Both groups were in Hardy-Weinberg equilibrium. The GCKR rs780094 polymorphism was associated with GDM in codominant and dominant models (P = 0.022 and P = 0.010, respectively). The minor allele (T) frequency for the control group in the study was 38.4% (95% CI: 32-44%), similar to frequencies reported for other Caucasian populations.

CONCLUSION

Carriers of the C allele of rs780094 were 1.41 (odds ratio, 95% CI, 0.97-2.03) times more likely to develop GDM.

Sydnone 1: A Mesoionic Compound with Antitumoral and Haematological Effects In Vivo

This study evaluated the antitumour activity of the mesoionic compound sydnone 1 (Syd-1) against Walker-256 carcinosarcoma. Tumour cells were subcutaneously inoculated in the hind limb in male Wistar rats. The animals were orally treated for 12 days with Syd-1 (75 mg/kg) or vehicle. At the end of treatment, considerable decreases in tumour volume and tumour weight were observed in treated animals. Samples of these tumours presented increases in apoptotic bodies and pro-apoptotic protein expression (Bax and p53), while the expression of the anti-apoptotic protein Bcl-2 was reduced. A decrease in reduced glutathione levels and an increase in glutathione peroxidase activity were observed in tumour after Syd-1 treatment. However, significant splenomegaly was evident in animals that received Syd-1, most likely attributable to the induction of haemolysis. This study demonstrated the antitumour activity of Syd-1 against Walker-256 carcinosarcoma. Its mechanism of action is linked to the activation of apoptotic pathways that lead to tumour cell death.

Mutational analysis of GlnB residues critical for NifA activation in Azospirillum brasilense

PII proteins are signal transduction that sense cellular nitrogen status and relay this signals to other targets. Azospirillum brasilense is a nitrogen fixing bacterium, which associates with grasses and cereals promoting beneficial effects on plant growth and crop yields. A. brasilense contains two PII encoding genes, named glnB and glnZ. In this paper, glnB was mutagenised in order to identify amino acid residues involved in GlnB signaling. Two variants were obtained by random mutagenesis, GlnBL13P and GlnBV100A and a site directed mutant, GlnBY51F, was obtained. Their ability to complement nitrogenase activity of glnB mutant strains of A. brasilense were determined. The variant proteins were also overexpressed in Escherichia coli, purified and characterized biochemically. None of the GlnB variant forms was able to restore nitrogenase activity in glnB mutant strains of A. brasilense LFH3 and 7628. The purified GlnBY51F and GlnBL13P proteins could not be uridylylated by GlnD, whereas GlnBV100A was uridylylated but at only 20% of the rate for wild type GlnB. Biochemical and computational analyses suggest that residue Leu13, located in the α helix 1 of GlnB, is important to maintain GlnB trimeric structure and function. The substitution V100A led to a lower affinity for ATP binding. Together the results suggest that NifA activation requires uridylylated GlnB bound to ATP.

The roles of ADAM33, ADAM28, IL-13 and IL-4 in the development of lung injuries in children with lethal non-pandemic acute infectious pneumonia

BACKGROUND

ADAM28, ADAM33, IL-13, IL-4 and other cytokines (IL-6 and IL-10) seem to play important roles in the persistence and maintenance of acute inflammatory processes that ultimately lead to lung remodeling and pulmonary fibrosis, which may be responsible for the high morbidity and mortality rates associated with non-pandemic acute viral pneumonias in childhood.

OBJECTIVES

The aim of this study was to evaluate the roles of ADAM33, ADAM28, IL4, IL6, IL10 and IL13 in the development of inflammation and alveolar fibrosis due to lethal acute respiratory infections of the lower airway in a pediatric population, especially in those with viral etiology.

STUDY DESIGN

For this study, 193 cases were selected, and samples from the cases were processed for viral antigen detection by immunohistochemistry and then separated into two groups: virus-positive (n=68) and virus-negative (n=125). Immunohistochemistry was performed to assess the presence of metalloproteinases (ADAM33 and ADAM28) and inflammatory cytokines (IL-4, IL-13, IL-6, IL-10) in the alveolar septa.

RESULTS

The virus-positive group showed stronger immunolabeling for ADAM33, ADAM28, IL-4 and IL-13 (p<0.0001 for all variables). The staining intensities for ADAM33 and ADAM28 were directly proportional to the intensities for IL-4 and IL-13 (p<0.0001).

CONCLUSIONS

The results of this study suggest that these proteins play important roles in pulmonary inflammatory reactions elicited against etiological viral agents. In addition, these mediators may affect the process of lung remodeling and the development of pulmonary fibrosis.

Fibronectin affects transient MMP2 gene expression through DNA demethylation changes in non-invasive breast cancer cell lines

Metastasis accounts for more than 90% of cancer deaths. Cells from primary solid tumors may invade adjacent tissues and migrate to distant sites where they establish new colonies. The tumor microenvironment is now recognized as an important participant in the signaling that induces cancer cell migration. An essential process for metastasis is extracellular matrix (ECM) degradation by metalloproteases (MMPs), which allows tumor cells to invade local tissues and to reach blood vessels. The members of this protein family include gelatinase A, or MMP-2, which is responsible for the degradation of type IV collagen, the most abundant component of the basal membrane, that separates epithelial cells in the stroma. It is known that fibronectin is capable of promoting the expression of MMP-2 in MCF7 breast cancer cells in culture. In addition, it was already shown that the MMP2 gene expression is regulated by epigenetic mechanisms. In this work, we showed that fibronectin was able to induce MMP2 expression by 30% decrease in its promoter methylation. In addition, a histone marker for an open chromatin conformation was significantly increased. These results indicate a new role for fibronectin in the communication between cancer cells and the ECM, promoting epigenetic modifications.

Detection of diarrheagenic Escherichia coli using a two-system multiplex-PCR protocol

BACKGROUND

Diarrheagenic Escherichia coli (DEC) strains are important causes of diarrhea. However, they cannot be distinguished from E. coli of the intestinal microbiota by conventional microbiological tests.

METHODS

This work presents a two-system multiplex PCR for detection of DEC. Primers for 16S rRNA gene were added as internal amplification control to validate negative reactions. The multiplex-PCR system 1 contains primers for detection of Shiga toxin producing E. coli (STEC; stx1, stx2), enteropathogenic E. coli (EPEC; eae, bfpA), atypical enteropathogenic E. coli (aEPEc; eae), enteroinvasive E. coli (ETEC; lt, st), enteroinvasive E. coli (EIEC; ial), and the internal amplification control 16S rRNA. The system 2 contains primers for EIEC (ipaH), enteroaggregative E. coli (CVD432), diffusely adherent E. coli (daaE), and 16S rRNA. The protocol was tested with E. coli reference strains, and also with cultures of fecal specimens of people with diarrhea and healthy controls.

RESULTS

The protocol correctly identified the DEC reference strains. No DEC marker was amplified for negative controls; these results were validated by the amplification of a fragment of the 16S rRNA gene. The frequency of DEC was 7.6% for both patients and healthy controls; two Shigella sonnei strains were detected in the group with diarrhea. The identity of the amplicons was confirmed by DNA sequencing.

CONCLUSION

The protocol is specific for DEC Shigella and is suitable for clinical laboratories.

Structural Changes in the Subcutaneous Compartment in Morbid Obesity

Most of the excess fat that accumulates in the morbidly obese is accommodated in the subcutaneous compartment (SCC), specifically in the adipose tissue lobules of the panniculus adiposus which enlarge and expand the SCC. However, the fibroelastic septa that are attached to the skin on one side of the SCC and to the deep fascia on the other invest each lobule and thereby offer resistance to the enlarging lobules. We report observations made during pathologic examinations of the abdominal wall SCC that were surgically excised by abdominal dermo-panniculectomy from 48 morbidly obese subjects after gastroplasty and weight loss. Lobules were large but varied notably upwards in size and, to some extent, shape. Simultaneously upon incision of the SCC, the lobules bulged above and the septa retracted below the same cut surfaces. Light microscopy revealed disruptions of septal elastic fibers, calcification of septa and septal arteries and necrosis of adipocytes, all sparsely distributed. Certain questions and facts emerge from these observations. Are the variations in lobule sizes normal, or do they reflect uneven fat deposition or mobilization during weight gain or loss respectively? Is there any correlation between lobule and adipocyte sizes? The tightly coupled phenomena of lobule-bulging and septal-retraction indicate that the lobules and septa are subjected to compressional and tensile stresses respectively in the intact, non-incised SCC. The histologic changes might be consequences of these stresses. Studies of the variations in body fat distribution and in adipocyte size have contributed to an understanding of obesity pathogenesis. The relevance of the present findings is unknown at this time, but these appear to have potential implications for studies of the morphogenesis of obesity. Confirmation of these findings, particularly the lobule variations, is required so that these can be compared with those in never-obese subjects and in morbidly obese subjects without prior weight loss.

Epigenetic changes of CXCR4 and its ligand CXCL12 as prognostic factors for sporadic breast cancer

Chemokines and their receptors are involved in the development and cancer progression. The chemokine CXCL12 interacts with its receptor, CXCR4, to promote cellular adhesion, survival, proliferation and migration. The CXCR4 gene is upregulated in several types of cancers, including skin, lung, pancreas, brain and breast tumors. In pancreatic cancer and melanoma, CXCR4 expression is regulated by DNA methylation within its promoter region. In this study we examined the role of cytosine methylation in the regulation of CXCR4 expression in breast cancer cell lines and also correlated the methylation pattern with the clinicopathological aspects of sixty-nine primary breast tumors from a cohort of Brazilian women. RT-PCR showed that the PMC-42, MCF7 and MDA-MB-436 breast tumor cell lines expressed high levels of CXCR4. Conversely, the MDA-MB-435 cell line only expressed CXCR4 after treatment with 5-Aza-CdR, which suggests that CXCR4 expression is regulated by DNA methylation. To confirm this hypothesis, a 184 bp fragment of the CXCR4 gene promoter region was cloned after sodium bisulfite DNA treatment. Sequencing data showed that cell lines that expressed CXCR4 had only 15% of methylated CpG dinucleotides, while the cell line that not have CXCR4 expression, had a high density of methylation (91%). Loss of DNA methylation in the CXCR4 promoter was detected in 67% of the breast cancer analyzed. The absence of CXCR4 methylation was associated with the tumor stage, size, histological grade, lymph node status, ESR1 methylation and CXCL12 methylation, metastasis and patient death. Kaplan-Meier curves demonstrated that patients with an unmethylated CXCR4 promoter had a poorer overall survival and disease-free survival. Furthermore, patients with both CXCL12 methylation and unmethylated CXCR4 had a shorter overall survival and disease-free survival. These findings suggest that the DNA methylation status of both CXCR4 and CXCL12 genes could be used as a biomarker for prognosis in breast cancer.

Biochemical properties, enterohaemolysin production and plasmid carriage of Shiga toxin-producing Escherichia coli strains

Thirty-eight strains of Shiga toxin-producing Escherichia coli (STEC) were characterised in terms of biochemical properties, enterohaemolysin production and plasmid carriage. A wide variation in the biochemical properties was observed among the STEC, with 14 distinct biotypes identified. Biotype 1 was the most common, found in 29% of the strains. Enterohaemolysin production was detected in 29% of the strains. Most of the bacterial strains (95%) carried one or more plasmids and considerable heterogeneity in size and combinations was observed. Seven distinct plasmid profiles were identified. The most common profile, characterised by the presence of a single plasmid of ~90 kb, was found in 50% of these strains. These data indicate extensive diversity among STEC strains. No correlation was found among biotype, serotype, enterohaemolysin production and plasmid profile.

The involvement of the nif-associated ferredoxin-like genes fdxA and fdxN of Herbaspirillum seropedicae in nitrogen fixation

The pathway of electron transport to nitrogenase in the endophytic beta-Proteobacterium Herbaspirillum seropedicae has not been characterized. We have generated mutants in two nif-associated genes encoding putative ferredoxins, fdxA and fdxN. The fdxA gene is part of the operon nifHDKENXorf1orf2fdxAnifQmodABC and is transcribed from the nifH promoter, as revealed by lacZ gene fusion. The fdxN gene is probably cotranscribed with the nifB gene. Mutational analysis suggests that the FdxA protein is essential for maximum nitrogenase activity, since the nitrogenase activity of the fdxA mutant strain was reduced to about 30% of that of the wild-type strain. In addition, the fdxA mutation had no effect on the nitrogenase switch-off in response to ammonium. Nitrogenase activity of a mutant strain lacking the fdxN gene was completely abolished. This phenotype was reverted by complementation with fdxN expressed under lacZ promoter control. The results suggest that the products of both the fdxA and fdxN genes are probably involved in electron transfer during nitrogen fixation.

ADAM33 gene silencing by promoter hypermethylation as a molecular marker in breast invasive lobular carcinoma

Background

ADAM33 protein is a member of the family of transmembrane glycoproteins composed of multidomains. ADAM family members have different activities, such as proteolysis and adhesion, making them good candidates to mediate the extracellular matrix remodelling and changes in cellular adhesion that characterise certain pathologies and cancer development. It was reported that one family member, ADAM23, is down-regulated by promoter hypermethylation. This seems to correlate with tumour progression and metastasis in breast cancer. In this study, we explored the involvement of ADAM33, another ADAM family member, in breast cancer.

Methods

First, we analysed ADAM33 expression in breast tumour cell lines by RT-PCR and western blotting. We also used 5-aza-2'-deoxycytidine (5azadCR) treatment and DNA bisulphite sequencing to study the promoter methylation of ADAM33 in breast tumour cell lines. We evaluated ADAM33 methylation in primary tumour samples by methylation specific PCR (MSP). Finally, ADAM33 promoter hypermethylation was correlated with clinicopathological data using the chi-square test and Fisher's exact test.

Results

The expression analysis of ADAM33 in breast tumour cell lines by RT-PCR revealed gene silencing in 65% of tumour cell lines. The corresponding lack of ADAM33 protein was confirmed by western blotting. We also used 5-aza-2'-deoxycytidine (5-aza-dCR) demethylation and bisulphite sequencing methodologies to confirm that gene silencing is due to ADAM33 promoter hypermethylation. Using MSP, we detected ADAM33 promoter hypermethylation in 40% of primary breast tumour samples. The correlation between methylation pattern and patient's clinicopathological data was not significantly associated with histological grade; tumour stage (TNM); tumour size; ER, PR or ERBB2 status; lymph node status; metastasis or recurrence. Methylation frequency in invasive lobular carcinoma (ILC) was 76.2% compared with 25.5% in invasive ductal carcinoma (IDC), and this difference was statistically significant (p = 0.0002).

Conclusion

ADAM33 gene silencing may be related to the discohesive histological appearance of ILCs. We suggest that ADAM33 promoter methylation may be a useful molecular marker for differentiating ILC and IDC.

A prospective study on Shiga toxin-producing Escherichia coli in children with diarrhea in Paraná State, Brazil

AIMS

To examine stool specimens from children with diarrhea from Paraná State, southern Brazil, for presence of STEC.

METHODS AND RESULTS

A PCR screening assay for stx genes was used to examine a loopful of confluent colonies of 306 stool samples cultures. In six (1.96%) of them, DNA fragments of the expected size were observed, and the presence of stx was confirmed by DNA sequencing. Then up to 100 single colonies from each of the six stool cultures were analyzed using the same PCR protocol. However, stx-positive colonies were found only in two of the cultures. The E. coli strains belonged to serotypes O69:H11 and O178:H19, and presented genotypes stx(1)eae ehxA and stx(1) respectively. Shiga toxin production was confirmed using the VTEC Screen Seiken. Except ampicillin, they were susceptible to all the antimicrobials tested.

CONCLUSIONS

These results show that STEC may be an important cause of diarrhea in children of Paraná State, and that they are present in low numbers in stools. The strains belonged to serotypes not commonly found associated with STEC and probably present low virulence.

SIGNIFICANCE AND IMPACT OF STUDY

These results indicate that molecular methods are required to diagnosis of STEC infections.

Effect of anntrCmutation on amino acid or urea utilization and on nitrogenase switch-off inHerbaspirillum seropedicae

Herbaspirillum seropedicae is a nitrogen-fixing bacterium that grows well with ammonium chloride or sodium nitrate as alternative single nitrogen sources but that grows more slowly with l-alanine, l-serine, l-proline, or urea. The ntrC mutant strain DCP286A was able to utilize only ammonium or urea of these nitrogen sources. The addition of 1 mmol·L–1ammonium chloride to the nitrogen-fixing wild-type strain inhibited nitrogenase activity rapidly and completely. Urea was a less effective inhibitor; approximately 20% of nitrogenase activity remained 40 min after the addition of 1 mmol·L–1urea. The effect of the ntrC mutation on nitrogenase inhibition (switch-off) was studied in strain DCP286A containing the constitutively expressed gene nifA of H. seropedicae. In this strain, nitrogenase inhibition by ammonium was completely abolished, but the addition of urea produced a reduction in nitrogenase activity similar to that of the wild-type strain. The results suggest that the NtrC protein is required for assimilation of nitrate and the tested amino acids by H. seropedicae. Furthermore, NtrC is also necessary for ammonium-induced switch-off of nitrogenase but is not involved in the mechanism of nitrogenase switch-off by urea.

Nitrogenase switch-off by ammonium ions in Azospirillum brasilense requires the GlnB nitrogen signal-transducing protein

Nitrogenase activity in several diazotrophs is switched off by ammonium and reactivated after consumption. The signaling pathway to this system in Azospirillum brasilense is not understood. We show that ammonium-dependent switch-off through ADP-ribosylation of Fe protein was partial in a glnB mutant of A. brasilense but absent in a glnB glnZ double mutant. Triggering of inactivation by anaerobic conditions was not affected in either mutant. The results suggest that glnB is necessary for full ammonium-dependent nitrogenase switch-off in A. brasilense.

Nitrogenase activity of Herbaspirillum seropedicae grown under low iron levels requires the products of nifXorf1 genes

Herbaspirillum seropedicae strains mutated in the nifX or orf1 genes showed 90% or 50% reduction in nitrogenase activity under low levels of iron or molybdenum respectively. Mutations in nifX or orf1 genes did not affect nif gene expression since a nifH::lacZ fusion was fully active in both mutants. nifX and the contiguous gene orf1 are essential for maximum nitrogen fixation under iron limitation and are probably involved in synthesis of nitrogenase iron or iron-molybdenum clusters.

Control of nitrogenase reactivation by the GlnZ protein in Azospirillum brasilense

The glnZ mutant of Azospirillum brasilense (strain 7611) showed only partial recovery (20 to 40%) after 80 min of ammonia-induced nitrogenase switch-off, whereas the wild type recovered totally within 10 min. In contrast, the two strains showed identical anoxic-induced switch-on/switch-off, indicating no cross talk between the two reactivation mechanisms.

Recent developments in the structural organization and regulation of nitrogen fixation genes in Herbaspirillum seropedicae

Herbaspirillum seropedicae is a nitrogen-fixing bacterium found in association with economically important gramineae. Regulation of nitrogen fixation involves the transcriptional activator NifA protein. The regulation of NifA protein and its truncated mutant proteins is described and compared with that of other nitrogen fixation bacteria. Nitrogen fixation control in H. seropedicae, of the beta-subgroup of Proteobacteria, has regulatory features in common with Klebsiella pneumoniae, of the gamma-subgroup, at the level of nifA expression and with rhizobia and Azospirillum brasilense, of the alpha-subgroup, at the level of control of NifA by oxygen.

Small bowel obstruction from internal hernia as a complication of colonoscopy

After colonoscopy with polypectomy, a patient developed a surgically acute abdomen. Although abdominal radiology did not show free air, a presumptive diagnosis of bowel perforation was made and laparotomy performed. At the time of surgery the colon was normal, and there was no peritoneal contamination. A loop of ileum was discovered incarcerated into an internal paracecal hernia. The bowel was freed, and the operation was completed without need for resection. Several cases of incarcerated inguinal hernia resulting from endoscopy are described in the medical literature; this is the first reported case of an incarcerated internal hernia as a complication of colonoscopy.

Sequencing and functional analysis of the nifENXorf1orf2 gene cluster of Herbaspirillum seropedicae

A 5.1-kb DNA fragment from the nifHDK region of H. seropedicae was isolated and sequenced. Sequence analysis showed the presence of nifENXorf1orf2 but nifTY were not present. No nif or consensus promoter was identified. Furthermore, orf1 expression occurred only under nitrogen-fixing conditions and no promoter activity was detected between nifK and nifE, suggesting that these genes are expressed from the upstream nifH promoter and are parts of a unique nif operon. Mutagenesis studies indicate that nifN was essential for nitrogenase activity whereas nifXorf1orf2 were not. High homology between the C-terminal region of the NifX and NifB proteins from H. seropedicae was observed. Since the NifX and NifY proteins are important for FeMo cofactor (FeMoco) synthesis, we propose that alternative proteins with similar activities exist in H. seropedicae.

Outcomes of coronary artery bypass surgery in elderly people

OBJECTIVES

To document the impact of coronary artery bypass (CABG) surgery on quality of life in elderly people three months after surgery; to compare quality of life measures; to examine predictors of poor quality of life; and to assess the predictive validity of global clinical rating scales.

STUDY DESIGN

Prospective cohort study with postoperative, three-month and one-year follow-up.

SETTING

A 700-bed tertiary care teaching hospital in Halifax, Nova Scotia.

PATIENTS

One hundred of 200 consecutive patients, 75 years and older, undergoing CABG.

MEASURES

Demographic information, clinical data and global clinical ratings were collected at baseline to assess risk for adverse outcome (death, stroke, functional impairment) at each follow-up. Quality of life three months post-CABG was documented using the RAND 36-Item Health Survey and the Seattle Angina Questionnaire.

MAIN RESULTS

Perioperative deaths occurred in four patients, disabling strokes in six and postoperative complications in seven. Three additional deaths occurred by the three-month follow-up and nine more by one year. On average, important improvements in quality of life were observed at three months' follow-up, using both assessments of quality of life.

CONCLUSIONS

Many elderly patients do well after CABG surgery, but a higher proportion than is seen in younger patients have complications leading to death and disability. A global clinical measure by the attending cardiologist at baseline did not identify patients at a higher risk. Follow-up studies are needed to assess long term outcomes of older patients at higher risk of death or a poor quality of life after CABG surgery.

Effect of nitrogen compounds on nitrogenase activity inHerbaspirillum seropedicaeSMR1

The effect of nitrogen compounds on growth and nitrogenase activity of Herbaspirillum seropedicae SMR1 was determined. L-Glutamate or L-glutamine as sole nitrogen sources supported growth, and nitrogenase activity was observed only after exhaustion of L-glutamate or L-glutamine from the culture medium. L-Serine, L-alanine, or ammonium chloride supported growth but not acetylene reduction activity. No growth was observed with L-histidine, L-lysine, L-arginine, or with the amines methylammonium chloride, tetramethylammonium chloride, or ethylenediamine chloride. All the compounds promoted the switch off of nitrogenase activity except L-histidine, L-lysine, or L-arginine, which were not taken up. The results showed that H. seropedicae cannot utilize exogenously added L-histidine, L-arginine, L-lysine, methylammonium chloride, tetramethylammonium chloride, or ethylediamine as the sole N source for growth. The inability of the positively charged amino acids to promote nitrogenase switch off might be a result of the lack of transport systems and the eventual further metabolism of these compounds.Key words: Herbaspirillum seropedicae, nitrogenase inactivation, amino compounds uptake.

Stress, coping, and social support as psychosocial factors in readmissions for ischaemic heart disease

This exploratory investigation aimed to identify psychological and social factors associated with early (4 months postdischarge) readmission to hospital of persons with ischaemic heart disease (IHD). Data on stress (Stress Appraisal Scale), coping strategies (Ways of Coping Questionnaire), and social network/social support (Norbeck Social Support Questionnaire) were collected from 100 persons with the primary diagnosis of IHD prior to discharge from hospital. Twenty-four persons were readmitted during the 4-month study period. The sample was divided into two groups for analysis: (1) persons with a first admission for IHD, and (2) persons with a prior history of admission for IHD. In comparison to persons with multiple admissions for cardiac illness, first time admissions appraised their IHD as less central and threatening, perceived less affective and affirmational support from health professionals, and identified health professionals less and neighbours more as sources of support. Greater use of the coping strategy 'seeking social support' was associated with the readmission of persons who had had their first admission for IHD. Less use of the coping strategy 'accepting responsibility' was associated with the readmission of persons who had a history of prior admission for IHD.

Cross-national interrater agreement on the clinical diagnostic criteria for dementia. WHO-PRA Age-Associated Dementia Working Group, WHO-Program for Research on Aging, Health of Elderly Program

We assessed the interobserver agreement on the clinical diagnosis of dementia syndrome and dementia subtypes as part of a cross-national project on the prevalence of dementia. Fourteen clinicians from the participating countries (Canada, Chile, Malta, Nigeria, Spain, and the United States) independently assessed the diagnosis of 51 patients whose clinical information was in standard records written in English. We used the DSM-III-R and ICD-10 criteria for dementia syndrome, the NINCDS-ADRDA criteria for Alzheimer's disease (AD), and the ICD-10 criteria for other dementing diseases, and measured interobserver agreement. We found comparable levels of agreement on the diagnosis of dementia using the DSM-III-R (kappa = 0.67) as well as the ICD-10 criteria (kappa = 0.69). Cognitive impairment without dementia was a major source of disagreement (kappa = 0.10). The kappa values were 0.58 for probable AD, 0.12 for possible AD, and rose to 0.72 when the two categories were merged. The interrater reproducibility of the diagnosis of vascular dementia was 0.66 in terms of kappa index; the diagnoses of other dementing disorders as a whole reached a kappa value of 0.40. This study suggests that clinicians from different cultures and medical traditions can use the DSM-III-R and the ICD-10 criteria for dementia effectively and thus reliably identify dementia cases in cross-national research. The interrater agreement on the diagnosis of dementia might be improved if clear-cut guidelines in the definition of cognitive impairment are provided. To improve the reliability of AD diagnosis in epidemiologic studies, we suggest that the NINCDS-ADRDA "probable" and "possible" categories be merged.

Characterization of the ribosomal DNA from Trichinella spiralis

Ribosomal DNA (rDNA) from three isolates of Trichinella was cloned into phage and sublcloned into the plasmid pBR322. The basic repeat unit of rDNA was variable in size, with the mapped clones ranging from 10-12 kb. There were differences in restriction sites within the genic region among the three isolates which were due to variations in the internal transcribed region (ITS) and the intergenic spacer (IGS). Three RsaI sites were mapped to the IGS repeat unit of the isolate AF1, and one RsaI site was mapped to the IGS repeat unit of Trichinella spiralis pseudospiralis (isolate Tp). The number of repetitive units in the IGS region varied markedly within and between the isolates. It was estimated that the basic repeat unit for the rDNA of isolate P1 was 10.6-28 kb, for AF1 10.7-37 kb, and for Tp it was 11-14.9 kb. There appeared to be a greater frequency of some sizes of the basic repeat unit in each of the populations, based on the relative intensity with which certain bands hybridize to the probe.

The effects of partial chronic denervation on forearm metabolism

Effects of chronic denervation upon in vivo forearm metabolism were studied in six patients and six controls. The diagnosis was amyotrophic lateral sclerosis in four patients, the neuronal form of Charcot-Marie Tooth disease in one patient, and an unclassified chronic disease of the lower motor neurons in one patient. In all cases the forearm muscles showed clinical weakness and electrical evidence of denervation, while muscle biopsy from a proximal muscle of the upper limb showed typical denervation atrophy. At rest there was increased oxygen utilization and lactate output as well as a tendency for increased uptake of glucose and long chain fatty acids from arterial blood per 100 ml of forearm tissue. During exercise the abnormally high lactate output increased further. An increased arterial lactate concentration was present during rest and exercise. Oxidation of fatty acids was not impaired. It is suggested that these abnormalities are consistent with an augmented utilization of blood borne fuels at rest by denervated muscles. A concurrent regional ischemia of muscles during rest and exercise, possibly due to defective autoregulation of skeletal muscle blood flow, may explain the abnormally high lactate generation.

Methadone-induced pulmonary edema

A patient with methadone-induced pulmonary edema had increased extravascular water in the lungs and a reduced total vascular albumin space. Diuresis resulted in hypotension. These observations suggest that the appropriate treatment of this condition should be ventilatory support and restoration of plasma oncotic pressure with albumin. Diuretic therapy should be used with caution.

The syndrome of systemic carnitine deficiency. Clinical, morphologic, biochemical, and pathophysiologic features

An 11-year old boy had had recurrent episodes of hepatic and cerebral dysfunction and underdeveloped musculature. Overt weakness developed at age 10. Lipid excess, especially in type I fibers, was found in muscle. Hypertrophied smooth endoplasmic reticulum and excessive microbodies were present in liver. Marked carnitine deficiency was shown in skeletal muscle, plasma, and liver. Ketogenesis was impaired on a high fat diet, but omega oxidation of fatty acids was enhanced. There was excessive glucose uptake and essentially no oxidation of labeled long-chain fatty acids by perfused forearm muscles in vivo. Oral replacement therapy restored plasma carnitine levels to normal, but not liver or muscle carnitine levels, and was accompanied by clinical improvement.