Green tea constituent epigallocatechin-3-gallate and induction of apoptosis and cell cycle arrest in human carcinoma cells

BACKGROUND AND PURPOSE

The polyphenolic compounds present in green tea show cancer chemopreventive effects in many animal tumor models. Epidemiologic studies have also suggested that green tea consumption might be effective in the prevention of certain human cancers. We investigated the effect of green tea polyphenols and the major constituent, epigallocatechin-3-gallate, on the induction of apoptosis (programmed cell death) and regulation of cell cycle in human and mouse carcinoma cells.

METHODS

Human epidermoid carcinoma cells (cell line A431), human carcinoma keratinocyte (cell line HaCaT), human prostate carcinoma cells (cell line DU145), mouse lymphoma cells (cell line L5178Y), and normal human epidermal keratinocytes (NHEKs) were used. Apoptosis was assessed by 1) the formation of internucleosomal DNA fragments by agarose gel electrophoresis, 2) confocal microscopy, and 3) flow cytometry after tagging the DNA fragments by fluorescence label. The distribution of cells in different phases of the cell cycle was analyzed by flow cytometry.

RESULTS

Treatment of A431 cells with green tea polyphenols and its components, epigallocatechin-3-gallate, epigallocatechin, and epicatechin-3-gallate, resulted in the formation of internucleosomal DNA fragments, characteristic of apoptosis. Treatment with epigallocatechin-3-gallate also resulted in apoptosis in HaCaT, L5178Y, and DU145 cells, but not in NHEK. Confocal microscopy and flow cytometry confirmed the findings. The DNA cell cycle analysis showed that in A431 cells, epigallocatechin-3-gallate treatment resulted in arrest in the G0-G1 phase of the cell cycle and a dose-dependent apoptosis.

CONCLUSIONS

Green tea may protect against cancer by causing cell cycle arrest and inducing apoptosis. It needs to be evaluated in human trials.

Seroepidemiology of Helicobacter pylori infection in India. Comparison of developing and developed countries

Helicobacter pylori (previously Campylobacter pylori) is now accepted as the major cause of type B gastritis and thus what is known about the epidemiology of type B gastritis can reasonably be transferred to H. pylori. We used a specific ELISA for anti-H. pylori IgG to study the prevalence of H. pylori infection in a population of lower socioeconomic class from Hyderabad, India. The results from India were compared to studies from other parts of the world. Two hundred thirty-eight individuals ages 3 to 70 participated. The frequency of H. pylori infection increased with age (P less than 0.01) and was greater than 80% by age 20. H. pylori infection was present in 79% of the population studied; there was no gender-related difference in prevalence of H. pylori infection. IgG antibody against hepatitis A (HAV) was rapidly acquired in Hyderabad; in a subset of 58 children between the ages of 3 and 21 tested, the frequency of anti-HAV was 98.2%. The prevalence of H. pylori infection increases with age in both developed and developing countries. The high age-specific prevalence of H. pylori infection in developing countries is probably a reflection of the lower socioeconomic level of those areas.

Protective effects of silymarin against photocarcinogenesis in a mouse skin model

BACKGROUND

Nonmelanoma skin cancer is the most common cancer among humans; solar UV is its major cause. Therefore, it is important to identify agents that can offer protection against this cancer.

PURPOSE

We evaluated the protective effects of silymarin, a flavonoid compound isolated from the milk thistle plant, against UVB radiation-induced nonmelanoma skin cancer in mice and delineated the mechanism(s) of its action.

METHODS

For long-term studies, three different protocols of treatment were employed, each evaluating protection by silymarin at a different stage of carcinogenesis. Female SKH-1 hairless mice were subjected to 1) UVB-induced tumor initiation followed by phorbol ester-mediated tumor promotion, 2) 7,12-dimethylbenz[a]anthracene-induced tumor initiation followed by UVB-mediated tumor promotion, and 3) UVB-induced complete carcinogenesis. Forty mice were used in each protocol and were divided into control and treatment groups. Silymarin was applied topically at a dose of 9 mg per application before UVB exposure, and its effects on tumor incidence (% of mice with tumors), tumor multiplicity (number of tumors per mouse), and average tumor volume per mouse were evaluated. In short-term studies, the following parameters were measured: formation of sunburn and apoptotic cells, skin edema, epidermal catalase and cyclooxygenase (COX) activities, and enzymatic activity and messenger RNA (mRNA) expression for ornithine decarboxylase (ODC), a frequently observed marker at tumor promotion stage. Fisher's exact test was used to evaluate differences in tumor incidence, two-sample Wilcoxon rank sum test was used for tumor multiplicity and tumor volume, and Student's t test was used for all other measurements. All statistical tests were two-sided.

RESULTS

In the protocol with UVB-induced tumor initiation, silymarin treatment reduced tumor incidence from 40% to 20% (P = .30), tumor multiplicity by 67% (P = .10), and tumor volume per mouse by 66% (P = .14). In the protocol with UVB-induced tumor promotion, silymarin treatment reduced tumor incidence from 100% to 60% (P<.003), tumor multiplicity by 78% (P<.0001), and tumor volume per mouse by 90% (P<.003). The effect of silymarin was much more profound in the protocol with UVB-induced complete carcinogenesis, where tumor incidence was reduced from 100% to 25% (P<.0001), tumor multiplicity by 92% (P<.0001), and tumor volume per mouse by 97% (P<.0001). In short-term experiments, silymarin application resulted in statistically significant inhibition in UVB-caused sunburn and apoptotic cell formation, skin edema, depletion of catalase activity, and induction of COX and ODC activities and ODC mRNA expression.

CONCLUSIONS AND IMPLICATION

Silymarin can provide substantial protection against different stages of UVB-induced carcinogenesis, possibly via its strong antioxidant properties. Clinical testing of its usefulness is warranted.

Anti-tumor-promoting activity of a polyphenolic fraction isolated from grape seeds in the mouse skin two-stage initiation-promotion protocol and identification of procyanidin B5-3'-gallate as the most effective antioxidant constituent

Procyanidins present in grape seeds are known to exert anti-inflammatory, anti-arthritic and anti-allergic activities, prevent skin aging, scavenge oxygen free radicals and inhibit UV radiation-induced peroxidation activity. Since most of these events are associated with the tumor promotion stage of carcinogenesis, these studies suggest that grape seed polyphenols and the procyanidins present therein could be anticarcinogenic and/or anti-tumor-promoting agents. Therefore, we assessed the anti-tumor-promoting effect of a polyphenolic fraction isolated from grape seeds (GSP) employing the 7,12-dimethylbenz[a]anthracene (DMBA)-initiated and 12-O-tetradecanoylphorbol 13-acetate (TPA)-promoted SENCAR mouse skin two-stage carcinogenesis protocol as a model system. Following tumor initiation with DMBA, topical application of GSP at doses of 0.5 and 1.5 mg/mouse/application to the dorsal initiated mouse skin resulted in a highly significant inhibition of TPA tumor promotion. The observed anti-tumor-promoting effects of GSP were dose dependent and were evident in terms of a reduction in tumor incidence (35 and 60% inhibition), tumor multiplicity (61 and 83% inhibition) and tumor volume (67 and 87% inhibition) at both 0.5 and 1.5 mg GSP, respectively. Based on these results, we directed our efforts to separate and identify the individual polyphenols present in GSP and assess their antioxidant activity in terms of inhibition of epidermal lipid peroxidation. Employing HPLC followed by comparison with authentic standards for retention times in HPLC profiles, physiochemical properties and spectral analysis, nine individual polyphenols were identified as catechin, epicatechin, procyanidins B1-B5 and C1 and procyanidin B5-3'-gallate. Five of these individual polyphenols with evident structural differences, namely catechin, procyanidin B2, procyanidin B5, procyanidin C1 and procyanidin B5-3'-gallate, were assessed for antioxidant activity. All of them significantly inhibited epidermal lipid peroxidation, albeit to different levels. A structure-activity relationship study showed that with an increase in the degree of polymerization in polyphenol structure, the inhibitory potential towards lipid peroxidation increased. In addition, the position of linkage between inter-flavan units also influences lipid peroxidation activity; procyanidin isomers with a 4-6 linkage showed stronger inhibitory activity than isomers with a 4-8 linkage. A sharp increase in the inhibition of epidermal lipid peroxidation was also evident when a gallate group was linked at the 3'-hydroxy position of a procyanidin dimer. Procyanidin B5-3'-gallate showed the most potent antioxidant activity with an IC(50) of 20 microM in an epidermal lipid peroxidation assay. Taken together, for the first time these results show that grape seed polyphenols possess high anti-tumor-promoting activity due to the strong antioxidant effect of procyanidins present therein. In summary, grape seed polyphenols in general, and procyanidin B5-3'-gallate in particular, should be studied in more detail to be developed as cancer chemopreventive and/or anticarcinogenic agents.

A multicentre observational study on the epidemiology, risk factors, management and outcomes of mucormycosis in India

OBJECTIVES

To describe the epidemiology, management and outcome of individuals with mucormycosis; and to evaluate the risk factors associated with mortality.

METHODS

We conducted a prospective observational study involving consecutive individuals with proven mucormycosis across 12 centres from India. The demographic profile, microbiology, predisposing factors, management and 90-day mortality were recorded; risk factors for mortality were analysed.

RESULTS

We included 465 patients. Rhino-orbital mucormycosis was the most common (315/465, 67.7%) presentation followed by pulmonary (62/465, 13.3%), cutaneous (49/465, 10.5%), and others. The predisposing factors included diabetes mellitus (342/465, 73.5%), malignancy (42/465, 9.0%), transplant (36/465, 7.7%), and others. Rhizopus species (231/290, 79.7%) were the most common followed by Apophysomyces variabilis (23/290, 7.9%), and several rare Mucorales. Surgical treatment was performed in 62.2% (289/465) of the participants. Amphotericin B was the primary therapy in 81.9% (381/465), and posaconazole was used as combination therapy in 53 (11.4%) individuals. Antifungal therapy was inappropriate in 7.6% (30/394) of the individuals. The 90-day mortality rate was 52% (242/465). On multivariate analysis, disseminated and rhino-orbital (with cerebral extension) mucormycosis, shorter duration of symptoms, shorter duration of antifungal therapy, and treatment with amphotericin B deoxycholate (versus liposomal) were independent risk factors of mortality. A combined medical and surgical management was associated with a better survival.

CONCLUSIONS

Diabetes mellitus was the dominant predisposing factor in all forms of mucormycosis. Combined surgical and medical management was associated with better outcomes. Several gaps surfaced in the management of mucormycosis. The rarer Mucorales identified in the study warrant further evaluation.

Cytokine cascade in dengue hemorrhagic fever: implications for pathogenesis

Dengue virus produces a mild acute febrile illness, dengue fever (DF) and a severe illness, dengue hemorrhagic fever (DHF). The characteristic feature of DHF is increased capillary permeability leading to extensive plasma leakage in serous cavities resulting in shock. The pathogenesis of DHF is not fully understood. This paper presents a cascade of cytokines, that in our view, may lead to DHF. The main feature is the early generation of a unique cytokine, human cytotoxic factor (hCF) that initiates a series of events leading to a shift from Th1-type response in mild illness to a Th2-type response resulting in severe DHF. The shift from Th1 to Th2 is regulated by the relative levels of interferon-gamma and interleukin (IL)-10 and between IL-12 and transforming growth factor-beta, which showed an inverse relationship in patients with DF.

Preparation and in vitro evaluation of liposomal/niosomal delivery systems for antipsoriatic drug dithranol

Dithranol is one of the mainstays in the topical treatment of psoriasis. However, the use of dithranol in psoriatic condition is inconvenient and troublesome, as it has irritating, burning, staining and necrotizing effect on the normal as well as the diseased skin. The entrapment of drug in vesicles is viewed to help in the localized delivery of the drug and an improved availability of the drug at the site will reduce the dose and in turn, the dose-dependent side effects like irritation and staining. The investigations deal with critical parameters controlling the formulation and stabilization of dithranol loaded liposomes and niosomes. The entrapment efficiency of dithranol in liposomes was optimized by altering the proportion of phosphatidyl choline and cholesterol, and in case of niosomes it was between Span 60 and cholesterol. Hydration and permeation mediums were also established keeping in view the poor solubility and stability of dithranol. The mean liposome and niosomes sizes were 4+/-1.25 and 5+/-1.5 microm, respectively. The drug-leakage study carried out at different temperatures of 4-8, 25+/-2 and 37 degrees C for a period of two months affirms that the drug leakage increased at a higher temperature. The in vitro permeation study using mouse abdominal skin shows significantly enhanced permeation with vesicles as indicated by flux of dithranol from liposomes (23.13 microg/cm(2)/h) and niosomes (7.78 microg/cm(2)/h) as compared with the cream base (4.10 microg/cm(2)/h).

Cell signaling and regulators of cell cycle as molecular targets for prostate cancer prevention by dietary agents

Prostate cancer (PCA) is the most common invasive malignancy and leading cause (after lung) of cancer deaths in males. Since PCA is initially androgen-dependent, strategies are targeted toward androgen depletion for its control. However, tumor re-growth mostly occurs following this modality, and is androgen-independent. A loss of functional androgen receptor and an enhanced expression of growth factor receptors (e.g. erbB family members) and associated ligands have been shown to be the causal genetic events in PCA progression. These genetic alterations lead to an epigenetic mechanism where a feed-back autocrine loop between membrane receptor (e.g. epidermal growth factor receptor [erbB1] and associated ligand (e.g. transforming growth factor-alpha) results in an enhanced activation of extracellular signal-regulated protein kinase 1/2 (ERK1/2) as an essential component of the uncontrolled growth of PCA at an advanced and androgen-independent stage. Together, we rationalized that inhibiting these epigenetic events would be useful in controlling advanced PCA growth. Dietary polyphenolic flavonoids and isoflavones are being studied extensively as cancer-preventive and interventive agents. Therefore, we focused our attention on silymarin, genistein, and epigallocatechin 3-gallate (EGCG), present in milk thistle, soy beans, and green tea, respectively. The effect of these agents was assessed on the erbB1-Shc-ERK1/2 signal transduction pathway, cell cycle regulatory molecules, and cell growth and death. In androgen-independent human prostate carcinoma DU145 cells, silymarin, genistein, and EGCG resulted in a significant to complete inhibition of transforming growth factor-alpha-caused activation of membrane receptor erbB1 followed by inhibition of downstream cytoplasmic signaling target Shc activation and a decrease in its binding with erbB1, without an alteration in their protein expression. Silymarin and genistein also inhibited ERK1/2 activation, suggesting that these agents impair the activation of erbB1-Shc-ERK1/2 signaling in DU145 cells. In the case of EGCG, a further increase in ERK1/2 activation was observed that was related to its pro-oxidant and apoptotic activities. Silymarin, genistein, and EGCG also resulted in a significant induction of Cip1/p21 and Kip1/p27 and a decrease in cyclin-dependent kinase (CDK) 4, but a moderate inhibition of CDK2, cyclin D1, and cyclin E was observed. An enhanced level of Cip1/p21 and Kip1/27 also led to an increase in their binding to CDK4 and CDK2. Treatment of cells with silymarin, genistein, and EGCG also resulted in strong cell growth inhibition at lower doses, and complete inhibition at higher doses. In contrast to silymarin, higher doses of genistein also showed cell death. A more profound cytotoxic effect was observed in the case of EGCG, with strong cell death at lower doses and complete loss of viability at higher doses. Together, these results suggest that cell signaling and regulators of cell cycle are potential epigenetic molecular targets for prostate cancer prevention by dietary agents. More studies, therefore, are needed with these agents to explore their anticarcinogenic potential against human prostate cancer.

ACE inhibition or angiotensin receptor blockade: impact on potassium in renal failure. VAL-K Study Group

BACKGROUND

Inhibition of the renin-angiotensin system is known to raise serum potassium [K(+)] levels in patients with renal insufficiency or diabetes. No study has evaluated the comparative effects of an angiotensin-converting enzyme (ACE) inhibitor versus an angiotensin receptor blocker (ARB) on the changes in serum [K(+)] in people with renal insufficiency.

METHODS

The study was a multicenter, randomized, double crossover design, with each period lasting one month. A total of 35 people (21 males and 14 females, 19 African Americans and 16 Caucasian) participated, with the mean age being 56 +/- 2 years. Mean baseline serum [K(+)] was 4.4 +/- 0.1 mEq/L. The glomerular filtration rate (GFR) was 65 +/- 5 mL/min/1.73 m(2), and blood pressure was 150 +/- 2/88 +/- 1 mm Hg. The main outcome measure was the difference from baseline in the level of serum [K+], plasma aldosterone, and GFR following the initial and crossover periods.

RESULTS

For the total group, serum [K(+)] changes were not significantly different between the lisinopril or valsartan treatments. The subgroup with GFR values of < or = 60 mL/min/1.73 m(2) who received lisinopril demonstrated significant increases in serum [K(+)] of 0.28 mEq/L above the mean baseline of 4.6 mEq/L (P = 0.04). This increase in serum [K(+)] was also accompanied by a decrease in plasma aldosterone (P = 0.003). Relative to the total group, the change in serum [K(+)] from baseline to post-treatment in the lisinopril group was higher among those with GFR values of < or = 60 mL/min/1.73 m(2). The lower GFR group taking valsartan, however, demonstrated a smaller rise in serum [K(+)], 0.12 mEq/L above baseline (P = 0.1), a 43% lower value when compared with the change in those who received lisinopril. This blunted rise in [K(+)] in people taking valsartan was not associated with a significant decrease in plasma aldosterone (P = 0.14).

CONCLUSIONS

In the presence of renal insufficiency, the ARB valsartan did not raise serum [K(+)] to the same degree as the ACE inhibitor lisinopril. This differential effect on serum [K(+)] is related to a relatively smaller reduction in plasma aldosterone by the ARB and is not related to changes in GFR. This study provides evidence that increases in serum [K(+)] are less likely with ARB therapy compared with ACE inhibitor therapy in people with renal insufficiency.

Prognostic importance of ambulatory blood pressure recordings in patients with chronic kidney disease

Ambulatory systolic blood pressure (BP) correlates better with risk factors for progression of chronic kidney disease (CKD) compared to clinic measured BP, but its role in predicting end-stage renal disease (ESRD) and death in patients with CKD is unknown. In a cohort study of 217 Veterans with CKD BP was measured by ambulatory monitoring and in the clinic. Twenty-four hour ambulatory BP was 133.5 +/- 16.6/73.1 +/- 11.1 mm Hg and clinic BP was 155.2 +/- 25.6/84.7 +/- 14.2 mm Hg. The composite renal end point of ESRD or death over a median follow-up of 3.5 years occurred in 75 patients (34.5%), death occurred in 52 patients (24.0%), and ESRD in 36/178 patients (20.2%). Thirty-nine patients died before reaching ESRD. One standard deviation (s.d.) increase in systolic BP increased the risk of composite outcome to 1.69 (95% confidence interval (CI) 1.32-2.17) for standard clinic measurement and to 1.88 (95% CI 1.48-2.39) for 24 h ambulatory BP recording. One s.d. increase in 24 h ambulatory systolic BP increased the risk of ESRD to 3.04 (95% CI 2.13-4.35) and to 2.20 (95% CI 1.43-3.39) when adjusted for standard clinic systolic BP. Non-dipping was associated with increased risk of total mortality and composite end point. In patients with CKD, BPs obtained by ambulatory monitoring are a stronger predictor of ESRD or death compared to BPs obtained in the clinic. Systolic ambulatory BP and nondipping are independent predictors for ESRD after adjusting for clinic BP. However, adjustment for other risk factors for CKD progression removes the independent prognostic value of ambulatory BP.

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

BACKGROUND

80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality.

METHODS

This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494.

FINDINGS

Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70-8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39-8·80) and upper-middle-income countries (2·06, 1·11-3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26-11·59) and upper-middle-income countries (3·89, 2·08-7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications.

INTERPRETATION

Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications.

FUNDING

National Institute for Health Research Global Health Research Unit.

Silibinin decreases prostate-specific antigen with cell growth inhibition via G1 arrest, leading to differentiation of prostate carcinoma cells: implications for prostate cancer intervention

Reduction in serum prostate-specific antigen (PSA) levels has been proposed as an endpoint biomarker for hormone-refractory human prostate cancer intervention. We examined whether a flavonoid antioxidant silibinin (an active constituent of milk thistle) decreases PSA levels in hormone-refractory human prostate carcinoma LNCaP cells and whether this effect has biological relevance. Silibinin treatment of cells grown in serum resulted in a significant decrease in both intracellular and secreted forms of PSA concomitant with a highly significant to complete inhibition of cell growth via a G1 arrest in cell cycle progression. Treatment of cells grown in charcoal-stripped serum and 5alpha-dihydrotestosterone showed that the observed effects of silibinin are those involving androgen-stimulated PSA expression and cell growth. Silibinin-induced G1 arrest was associated with a marked decrease in the kinase activity of cyclin-dependent kinases (CDKs) and associated cyclins because of a highly significant decrease in cyclin D1, CDK4, and CDK6 levels and an induction of Cip1/p21 and Kip1/p27 followed by their increased binding with CDK2. Silibinin treatment of cells did not result in apoptosis and changes in p53 and bcl2, suggesting that the observed increase in Cip1/p21 is a p53-independent effect that does not lead to an apoptotic cell death pathway. Conversely, silibinin treatment resulted in a significant neuroendocrine differentiation of LNCaP cells as an alternative pathway after Cip1/p21 induction and G1 arrest. Together, these results suggest that silibinin could be a useful agent for the intervention of hormone-refractory human prostate cancer.

Protection against ultraviolet B radiation-induced photocarcinogenesis in hairless mice by green tea polyphenols

Our recent studies have shown that polyphenols present in green tea (GTP) possess significant antigenotoxic activity and afford protection against polycyclic aromatic hydrocarbon-induced skin tumor initiation in mice. In this study we assessed the effect of oral feeding and topical application of GTP on ultraviolet B (UVB) radiation-induced skin carcinogenesis in female SKH-1 hairless mice. Chronic oral feeding of GTP (0.1%, w/v) in drinking water resulted in significantly (P less than 0.01) lower tumor yield (percent of animals with tumors and number of tumors per mouse) and extended TDT50 (P less than 0.05), as compared to animals receiving normal drinking water. Topical application of GTP before UVB irradiation also afforded protection against photocarcinogenesis; however, the protective response was lower than that observed by oral feeding of GTP in drinking water. These results, in conjunction with our prior publications, suggest that consumption of green tea may reduce the risk of some forms of human cancer induced by both physical and chemical environmental carcinogens.

Computer-assisted sleep staging

To address the subjectivity in manual scoring of polysomnograms, a computer-assisted sleep staging method is presented in this paper. The method uses the principles of segmentation and self-organization (clustering) based on primitive sleep-related features to find the pseudonatural stages present in the record. Sample epochs of these natural stages are presented to the user, who can classify them according to the Rechtschaffen and Kales (RK) or any other standard. The method then learns from these samples to complete the classification. This step allows the active participation of the operator in order to customize the staging to his/her preferences. The method was developed and tested using 12 records of varying types (normal, abnormal, male, female, varying age groups). Results showed an overall concurrence of 80.6% with manual scoring of 20-s epochs according to RK standard. The greatest amount of errors occurred in the identification of the highly transitional Stage 1, 54% of which was misclassified into neighboring stages 2 or Wake.

Pleurodesis for malignant pleural effusions

BACKGROUND

Approximately half of all patients with metastatic cancer develop a malignant pleural effusion which is likely to lead to a significant reduction in quality of life secondary to symptoms such as dyspnoea and cough. The aim of pleurodesis in these patients is to prevent re-accumulation of the effusion and thereby of symptoms, and avoid the need for repeated hospitalization for thoracocentesis. Numerous clinical studies have been performed to try to determine the optimal pleurodesis strategy, and synthesis of the available evidence should facilitate this.

OBJECTIVES

The aims of this review were to ascertain the optimal technique of pleurodesis in cases of malignant pleural effusion; to confirm the need for a sclerosant; and to clarify which, if any, of the sclerosants is the most effective.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials was searched for studies on 'pleurodesis'. Studies for inclusion were also identified from MEDLINE (1980 to June 2002) and EMBASE (1980 to May 2002). No language restriction was applied.

SELECTION CRITERIA

RCTs of adults subjects undergoing pleurodesis for pleural effusion in the context of metastatic malignancy (or a malignant process leading to pleural effusion) were included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected studies for inclusion in the review, and extracted data using a standard data collection form. Primary outcome measures sought were effectiveness of pleurodesis as defined by freedom from recurrence of effusions, and mortality after pleurodesis. Secondary outcomes were adverse events due to pleurodesis. Dichotomous data were meta-analysed using a fixed effect model and expressed as relative risk. The number-needed-to-treat (NNT) was calculated for pleurodesis efficacy. In addition, for adverse events, the overall percentage of patients across studies exhibiting a particular adverse effect such as fever, pain, or gastrointestinal symptoms was calculated.

MAIN RESULTS

A total of 36 RCTs with 1499 subjects were eligible for meta-analysis. The use of sclerosants (mitozantrone, talc and tetracycline combined)compared with control (instillation of isotonic saline or equivalent pH isotonic saline or tube drainage alone) was associated with an increased efficacy of pleurodesis. The relative risk (RR) of non-recurrence of an effusion is 1.20 (95% CI 1.04 to 1.38) in favour of the use of sclerosants based on five studies with a total 228 subjects. Comparing different sclerosants, talc was found to be the most efficacious. The RR of effusion non-recurrence was 1.34 (95% CI 1.16 to 1.55) in favour of talc compared with bleomycin, tetracycline, mustine or tube drainage alone based on 10 studies comprising 308 subjects. This was not associated with increased mortality post pleurodesis. The RR of death was 1.19 (95% CI 0.08 to 1.77) for talc compared to bleomycin, tetracycline, mustine and tube drainage alone based on six studies of 186 subjects. Death was not reported in all studies and, when reported, was attributed to underlying disease, only one death being reported as procedure-related. In the comparison of thoracoscopic versus medical pleurodesis, thoracoscopic pleurodesis was found to be more effective. The RR of non-recurrence of effusion is 1.19 (95% CI 1.04 to 1.36) in favour of thoracoscopic pleurodesis compared with tube thoracostamy pleurodesis utilizing talc as sclerosant based on two studies with 112 subjects. Comparing thoracoscopic versus bedside instillation (with different sized chest tubes) of various sclerosants (tetracycline, bleomycin, talc or mustine) the RR of non-recurrence of effusion is 1.68 (95% CI 1.35 to 2.10) based on five studies with a total of 145 participants.Adverse events were not reported adequately to enable meta-analysis.

REVIEWER'S CONCLUSIONS

The available evidence supports the need for chemical sclerosants for successful pleurodesis, the use of talc as the sclerosant of choice, and thoracoscopic pleurodesis as the preferred technique for pleurodesis based on efficacy. There was no evidence for an increase in mortality following talc pleurodesis.

Protection against ultraviolet-B radiation-induced local and systemic suppression of contact hypersensitivity and edema responses in C3H/HeN mice by green tea polyphenols

Exposure of skin to UV radiation can cause diverse biological effects, including induction of inflammation, alteration in cutaneous immune cells and impairment of contact hypersensitivity (CHS) responses. Our laboratory has demonstrated that oral feeding as well as topical application of a polyphenolic fraction isolated from green tea (GTP) affords protection against the carcinogenic effects of UVB (280-320 nm) radiation. In this study, we investigated whether GTP could protect against UVB-induced immunosuppression and cutaneous inflammatory responses in C3H mice. Immunosuppression was assessed by contact sensitization with 2,4-dinitrofluorobenzene applied to UVB-irradiated skin (local suppression) or to a distant site (systemic suppression), while double skin-fold swelling was used as the measure of UVB-induced inflammation. Topical application of GTP (1-6 mg/animal), 30 min prior to or 30 min after exposure to a single dose of UVB (2 kJ/m2) resulted in significant protection against local (25-90%) and systemic suppression (23-95%) of CHS and inflammation in mouse dorsal skin (70-80%). These protective effects were dependent on the dose of GTP employed; increasing the dose (1-6 mg/animal) resulted in an increased protective effect (25-93%). The protective effects were also dependent on the dose of UVB (2-32 kJ/m2). Among the four major epicatechin derivatives present in GTP, (-)-epigallocatechin-3-gallate, the major constituent in GTP, was found to be the most effective in affording protection against UVB-caused CHS and inflammatory responses. Our study suggests that green tea, specifically polyphenols present therein, may be useful against inflammatory dermatoses and immunosuppression caused by solar radiation.

When do newborns die? A systematic review of timing of overall and cause-specific neonatal deaths in developing countries

About 99% of neonatal deaths occur in low- and middle-income countries. There is a paucity of information on the exact timing of neonatal deaths in these settings. The objective of this review was to determine the timing of overall and cause-specific neonatal deaths in developing country settings. We searched MEDLINE via PubMed, Cochrane CENTRAL, WHOLIS and CABI using sensitive search strategies. Searches were limited to studies involving humans published in the last 10 years. A total of 22 studies were included in the review. Pooled results indicate that about 62% of the total neonatal deaths occurred during the first 3 days of life; the first day alone accounted for two-thirds. Almost all asphyxia-related and the majority of prematurity- and malformation-related deaths occurred in the first week of life (98%, 83% and 78%, respectively). Only one-half of sepsis-related deaths occurred in the first week while one-quarter occurred in each of the second and third to fourth weeks of life. The distribution of both overall and cause-specific mortality did not differ greatly between Asia and Africa. The first 3 days after birth account for about 30% of under-five child deaths. The first week of life accounts for most of asphyxia-, prematurity- and malformation-related mortality and one-half of sepsis-related deaths.

Pathophysiology of potassium absorption and secretion by the human intestine

When normal people ingest 90 mEq/day of K+ in their diet, they absorb about 90% of intake (81 mEq) and excrete an equivalent amount of K+ in the urine. Normal fecal K+ excretion averages about 9 mEq/day. The vast majority of intestinal K+ absorption occurs in the small intestine; the contribution of the normal colon to net K+ absorption and secretion is trivial. K+ is absorbed or secreted mainly by passive mechanisms; the rectum and perhaps the sigmoid colon have the capacity to actively secrete K+, but the quantitative and physiological significance of this active secretion is uncertain. Hyperaldosteronism increases fecal K+ excretion by about 3 mEq/day in people with otherwise normal intestinal tracts. Cation exchange resin by mouth can increase fecal K+ excretion to 40 mEq/day. The absorptive mechanisms of K+ are not disturbed by diarrhea per se, but fecal K+ losses are increased in diarrheal diseases by unabsorbed anions (which obligate K+), by electrochemical gradients secondary to active chloride secretion, and probably by secondary hyperaldosteronism. In diarrhea, total body K+ can be reduced by two mechanisms: loss of muscle mass because of malnutrition and reduced net absorption of K+; only the latter causes hypokalemia. Balance studies in patients with diarrhea are exceedingly rare, but available data emphasize an important role for dietary K+ intake, renal K+ excretion, and fecal K+ losses in determining whether or not a patient develops hypokalemia. The paradoxical negative K+ balance induced by ureterosigmoid anastomosis is described. The concept that fecal K+ excretion is markedly elevated in patients with uremia as an intestinal adaptation to prevent hyperkalemia is analyzed; we conclude that the data do not convincingly show the existence of a major intestinal adaptive response to chronic renal failure.

Prognostic importance of clinic and home blood pressure recordings in patients with chronic kidney disease

Blood pressure (BP) measured only in the clinic substantially misclassifies hypertension in patients with chronic kidney disease (CKD). The role of out-of-clinic recordings of BP in predicting end-stage renal disease (ESRD) and death in patients with CKD is unknown. A prospective cohort study was conducted in 217 Veterans with CKD. BP was measured at home and in the clinic by 'routine' and standardized methods. Patients were followed over a median of 3.5 years to assess the end points of total mortality, ESRD or the composite outcome of ESRD or death. Home BP was 147.0+/-21.4/78.3+/-11.6 mmHg and clinic BPs were 155.2+/-25.6/84.7+/-14.2 mmHg by standardized method and 144.5+/-24.2/75.4+/-14.7 mmHg by the 'routine' method. The composite renal end point occurred in 75 patients (34.5%), death in 52 patients (24.0%), and ESRD in 36/178 patients (20.2%). One standard deviation (s.d.) increase in systolic BP increased the risk of renal end point by 1.27 (95% confidence interval (CI) 1.01-1.60) for routine clinic measurement, by 1.69 (95% CI 1.32-2.17) for standardized clinic measurement and by 1.84 (95% CI 1.46-2.32) for home BP recording. One s.d. increase in home systolic BP increased the risk of ESRD by 1.74 (95% CI 1.04-2.93) when adjusted for standardized clinic systolic BP, proteinuria, estimated glomerular filtration rate, and other risk factors. In patients with CKD, BPs obtained at home are a stronger predictor of ESRD or death compared to BPs obtained in the clinic. Systolic home BP is an independent predictor for ESRD.

Indian study on epidemiology of asthma, respiratory symptoms and chronic bronchitis in adults (INSEARCH)

SETTING

Field sites in 12 districts in different parts of India.

OBJECTIVE

To determine the nationwide population prevalence of and risk factors for asthma and chronic bronchitis (CB) in adults.

DESIGN

A standardised validated questionnaire based on the International Union Against Tuberculosis and Lung Disease's 1984 questionnaire was used to assess asthma and CB prevalence. Multivariate logistic regression analyses were performed to determine the risk factor associations. Estimates standardised to the 2011 population projection estimates for India were used to calculate the national disease burden.

RESULTS

A total of 85,105 men and 84,470 women from 12 urban and 11 rural sites were interviewed. One or more respiratory symptoms were present in 8.5% of individuals. The overall prevalence of asthma and CB was respectively 2.05% (adults aged ≥15 years) and 3.49% (adults aged ≥35 years). Advancing age, smoking, household environmental tobacco smoke exposure, asthma in a first-degree relative, and use of unclean cooking fuels were associated with increased odds of asthma and CB. The national burden of asthma and CB was estimated at respectively 17.23 and 14.84 million.

CONCLUSION

Asthma and CB in adults pose an enormous health care burden in India. Most of the associated risk factors are preventable.

Elevated levels of IL-8 in dengue hemorrhagic fever

Dengue virus causes dengue fever, a mild febrile illness, and at times dengue hemorrhagic fever (DHF), a severe illness the pathogenesis of which is not fully understood. Given the crucial roles played by interleukin-8 (IL-8) as a chemoattractant cytokine and in inflammatory processes, levels of circulating IL-8 in the sera and IL-8 mRNA in the peripheral blood mononuclear cells (PBMC) were measured in 99 patients of a recent dengue epidemic that occurred in India in 1996 and in 21 normal healthy controls. Twenty-six of the patients had dengue fever (DF) and the remaining 73 were diagnosed as having different grades of DHF. All the control normal sera were negative for IL-8, so were their PBMC for IL-8 mRNA. Increased levels of IL-8 in the sera and IL-8 mRNA in their PBMC were observed in patients with severe illness of DHF grades III and IV. Only two out of 26 patients of DF and one out of 10 DHF grade I patient were positive for IL-8 and all three deteriorated to DHF grade IV within 24 hr. All six patients of DHF grade IV who died had higher serum level of IL-8 above 200 pg/ml, the highest being 5,568 pg/ml in one patient; the presence of mRNA for IL-8 was very high in all patients. A striking correlation was observed between increased levels of IL-8 and severe DHF, with greater levels in patients with increased grade of the disease and death. These results suggest that IL-8 may have an important role and may be an indicator of increasing severity of the disease and death.