Making surgery safer in an increasingly digital world: the internet-friend or foe?

PURPOSE: The internet has resulted in huge efficiency gains in health care, the ability to deal with massive data accumulation and better manage patient data. However, potential and real pitfalls exist, including breeches in security of data and patient confidentiality, data storage issues, errors, and user interface issues. METHODS: A MEDLINE review was performed using MeSH terms "health care" and "information technology." Cross-referencing was used to explore the different opportunities and challenges the internet has to offer. RESULTS: As health professionals, we are fast adopting technologies at our fingertips, such as WhatsApp and video capabilities, into our clinical practice to increase productivity and improve patient care. However, the potential security breaches are significant for the health professional and health service. Further, electronic medical records have theoretical advantages to improve patient care, reduce medication errors, and expedite referrals. The downside is a less personalized approach to patient care, as well as the potential for these systems to be even more cumbersome. In regard to the acquisition of knowledge, there is no doubt the internet is our friend. Health care professionals as well as patients have unlimited resources for learning, including podcasts videos, apps, simulators, and wearable devices. Unfortunately, this comes with a risk of misinformation and poorly referenced data with little to no regulation of content. CONCLUSION: In this increasing digital world, it is our task as health care providers to embrace these new technologies but develop guidelines and control systems to minimize the pitfalls.

Aberrant methylation of donor genome in cloned bovine embryos.

Despite recent successes in cloning various animal species, the use of somatic cells as the source of donor nuclei has raised many practically relevant questions such as increased abortion rates, high birth weight and perinatal death. These anomalies may be caused by incomplete epigenetic reprogramming of donor DNA. Genome-wide demethylation occurs during early development, 'erasing' gamete-specific methylation patterns inherited from the parents. This process may be a prerequisite for the formation of pluripotent stem cells that are important for the later development. Here, we provide evidence that cloned bovine embryos may have impaired epigenetic reprogramming capabilities. We found highly aberrant methylation patterns in various genomic regions of cloned embryos. Cloned blastocysts closely resembled donor cells in their overall genomic methylation status, which was very different from that of normal blastocysts produced in vitro or in vivo. We found demethylation of the Bov-B long interspersed nuclear element sequence in normal embryos, but not in cloned embryos, in which the donor-type methylation was simply maintained during preimplantation development. There were also significant variations in the degree of methylation among individual cloned blastocysts. Our findings indicate that the developmental anomalies of cloned embryos could be due to incomplete epigenetic reprogramming of donor genomic DNA.

Loss of p14ARF in tumor cells facilitates replication of the adenovirus mutant dl1520 (ONYX-015).

The adenovirus mutant dl1520 (ONYX-015) does not express the E1B-55K protein that binds and inactivates p53. This virus replicates in tumor cells with mutant p53, but not in normal cells with functional p53. Although intra-tumoral injection of dl1520 shows promising responses in patients with solid tumors, previous in vitro studies have not established a close correlation between p53 status and dl1520 replication. Here we identify loss of p14ARF as a mechanism that allows dl1520 replication in tumor cells retaining wild-type p53. We demonstrate that the re-introduction of p14ARF into tumor cells with wild-type p53 suppresses replication of dl1520 in a p53-dependent manner. Our study supports the therapeutic use of dl1520 in tumors with lesions within the p53 pathway other than mutation of p53.

Effects of reactive oxygen species on proliferation of Chinese hamster lung fibroblast (V79) cells.

Reactive oxygen species (ROS) have emerged as important signaling molecules in the regulation of various cellular processes. In our study, we investigated the effect of a wide range of ROS on Chinese hamster lung fibroblast (V79) cell proliferation. Treatment with H2O2 (100 microM), superoxide anion (generated by 1 mM xanthine and 1 mU/ml xanthine oxidase), menadione, and phenazine methosulfate increased the cell proliferation by approximately 50%. Moreover, a similar result was observed after partial inhibition of superoxide dismutase (SOD) and glutathione peroxidase. This upregulation of cell proliferation was suppressed by pretreatment with hydroxyl radical scavengers and iron chelating agents. In addition to ROS, treatment with exogenous catalase and SOD mimic (MnTMPyP) suppressed the normal cell proliferation. Short-term exposure of the cells to 100 microM H2O2 was sufficient to induce proliferation, which indicated that activation of the signaling pathway is important as an early event. Accordingly, we assessed the ability of H2O2 to activate mitogen-activated protein kinases (MAPK). Jun-N-terminal kinase (JNK) and p38 MAPK were both rapidly and transiently activated by 100 microM H2O2, with maximal activation 30 min after treatment. However, the activity of extracellular signal-regulated kinase (ERK) was not changed. Pretreatment with SB203580 and SB202190, specific inhibitors of p38 MAPK, reduced the cell proliferation induced by H2O2. The activation of both JNK and p38 MAPK was also suppressed by pretreatment with hydroxyl radical scavenger and iron chelating agents. Our results suggest that the trace metal-driven Fenton reaction is a central mechanism that underlies cell proliferation and MAPK activation.

Se-methylselenocysteine induces apoptosis mediated by reactive oxygen species in HL-60 cells.

Recent studies have implicated apoptosis as one of the most plausible mechanisms of the chemopreventive effects of selenium compounds, and reactive oxygen species (ROS) as important mediators in apoptosis induced by various stimuli. In the present study, we demonstrate that Se-methylselenocysteine (MSC), one of the most effective selenium compounds at chemoprevention, induced apoptosis in HL-60 cells and that ROS plays a crucial role in MSC-induced apoptosis. The uptake of MSC by HL-60 cells occurred quite early, reaching the maximum within 1 h. The dose-dependent decrease in cell viability was observed by MSC treatment and was coincident with increased DNA fragmentation and sub-G(1) population. 50 microM of MSC was able to induce apoptosis in 48% of cell population at a 24 h time point. Moreover, the release of cytochrome c from mitochondria and the activation of caspase-3 and caspase-9 were also observed. The measurement of ROS by dichlorofluorescein fluorescence revealed that dose- and time-dependent increase in ROS was induced by MSC. N-acetylcysteine, glutathione, and deferoxamine blocked cell death, DNA fragmentation, and ROS generation induced by MSC. Moreover, N-acetylcysteine effectively blocked caspase-3 activation and the increase of the sub-G(1) population induced by MSC. These results imply that ROS is a critical mediator of the MSC-induced apoptosis in HL-60 cells.

Chemopreventive effect of chlorophyllin on mutagenicity and cytotoxicity of 6-sulfooxymethylbenzo[a]pyrene.

The chemopreventive activity of chlorophyllin (CHL) was monitored by using 6-sulfooxymethylbenzo[a]pyrene (SMBP) which is an ultimate metabolite of benzo[a]pyrene (B[a]P). CHL was quite effective in reducing both cytotoxicity and mutagenicity for SMBP in dose dependent manner up to 12.5 mM CHL in Chinese hamster V79 cells. The inhibitory patterns of CHL for SMBP were also confirmed in Salmonella typhimurium strains TA98 and TA100. Mutation frequency caused by SMBP was diminished almost to a control level at a 50 nmol CHL. A similar but less effective prevention of CHL was indicated in the mammalian and the bacterial mutagenicity assays with 6-hydroxymethylbenzo[a]pyrene (HMBP). The inhibitory effect of CHL against assault of SMBP on V79 cells was found to be related to the reduced cellular uptake of SMBP and further the remarkably lowered DNA adducts.

Inhibitory effects of chlorophyllin on 7,12-dimethylbenz[a]anthracene-induced bacterial mutagenesis and mouse skin carcinogenesis.

Chlorophyllin (CHL), a water-soluble derivative of chlorophyll, has been used for the treatment of several abnormal human conditions without apparent toxicity. Recent studies have revealed that CHL has the excellent chemopreventive potential. In the present investigation, we have found the inhibitory activities of CHL against 7,12-dimethylbenz[a]anthracene (DMBA)-induced mutagenesis in Salmonella typhimurium TA100 and also on DMBA-initiated and 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-promoted mouse skin tumor formation. The incidence and the multiplicity of skin tumors were not significantly decreased in mice by a single topical application of CHL prior to the DMBA treatment, but there was a marked suppression of papillomagenesis in mice treated with CHL during the promotional stage. Furthermore, the formation of DMBA-induced papillomagenesis was reduced in all mice that had received CHL for 6 weeks following treatment with TPA for 6, 18 and 24 weeks. These results indicate that CHL can inhibit both tumor promotion and the progression of papillomagenesis in the two-stage mouse skin carcinogenesis induced by DMBA and TPA.

Differential effect of cadmium on GSH-peroxidase activity in the Leydig and the Sertoli cells of rat testis. Suppression by selenium and the possible relationship to heme concentration.

In the testes of rats treated with cadmium acetate (7 or 20 mumoles/kg, 24 hr, s.c.), the activity of glutathione (GSH)-peroxidase was increased. At the same time, the activity of glutathione disulfide (GSSG)-reductase and the cellular GSH concentration were decreased significantly. The basal activity of peroxidase in the Leydig and the Sertoli cell populations was comparable. However, the magnitude of increases in the activities markedly differed in the two cell populations, with that of the Sertoli cells increasing to nearly 450% of the control value in response to treatment with 20 mumoles/kg Cd2+. In the Leydig cells, the enzyme activity in response to the same treatment increased to only about 170% of the control value. Cd2+ treatment increased the concentration of heme in the microsomal and the smooth and rough endoplasmic reticulum fractions of the whole testis, as well as in the microsomal fractions of the Leydig and the Sertoli cells. As with the peroxidase activity, the two cell populations vastly differed in their susceptibilities to Cd2+ treatment, with the Sertoli cells being more severely affected by the metal. In the Sertoli cells the microsomal heme concentration was increased by approximately 11-fold, whereas only a 2-fold increase in the Leydig cells was noted. The increase in GSH-peroxidase activity was not due to the peroxidase activity of GSH-S-transferases, insofar as an increase in transferase activity was not observed in the Leydig and the Sertoli cells. Treatment of rats with sodium selenite (10 mumoles/kg, s.c.) 30 min before Cd2+ treatment (20 mumoles/kg) fully suppressed the above-described spectrum of effects of Cd2+ in the testis. Also, sodium selenite at a lower dose of 5 mumoles/kg prevented an increase in GSH-peroxidase activity. It is hypothesized that increased GSH-peroxidase activity in the Leydig and the Sertoli cells constitutes an adaptive response to increased cellular levels of heme and to the free radicals generated by the heme molecule. Selenium prevents the increase in GSH-peroxidase activity by circumventing the increase in cellular heme concentration. The protection is believed to be related, at least in part, to increased production of cellular GSH.

Inhibition of the enzymes of glutathione metabolism by mercuric chloride in the rat kidney: reversal by selenium.

The treatment of rats with 10 mumoles/kg (s.c.) of mercuric chloride (Hg2+) caused time-dependent decreases in the activities of the enzymes of the glutathione (GSH) metabolism pathway in the kidney. Twenty-four hours after administration of Hg2+, the activities of gamma-glutamylcysteine synthetase and glutathione disulfide (GSSG)-reductase in the kidney were decreased by 50-60%, and the activities of the GSH catabolic enzymes, gamma-glutamyl transpeptidase and GSH-peroxidase, were decreased by 25-35%. In the liver, only the activity of GSSG-reductase was decreased at this time. The observed decreases in the enzyme activities were not accompanied by a depression in the cellular protein concentration. The same pattern of enzyme response was noted when rats were given 30 mumoles/kg Hg2+; however, the decreases in the specific activity of the enzymes were accompanied by great losses in the cellular protein concentrations in both the liver and the kidney (35-40%). This dose of Hg2+ also caused significant decreases in the concentration of GSH in both organs. In vitro, Hg2+ only inhibited the activity of GSSG-reductase. When rats were given sodium selenite (Na2SeO3; 5, 10 or 20 mumoles/kg, s.c.) 30 min after Hg2+ treatment (10 mumoles/kg), the Hg2+-related depressions in the activities of the enzymes of GSH metabolism in the liver and the kidney were blocked. Also, in rats treated with 30 mumoles/kg Hg2+, the administration of 10 mumoles/kg selenium significantly decreased the magnitude of depression in the concentration of GSH in the kidney.

Inhibition mechanisms of bioflavonoids extracted from the bark of Pinus maritima on the expression of proinflammatory cytokines.

The effect of bioflavonoids extracted from the bark of Pinus maritima, Pycnogenol (PYC), on gene expression of the proinflammatory cytokines interleukin-1beta (IL-1beta) and interleukin-2 (IL-2) were investigated in RAW 264.7 cells and Jurkat E6.1 cells, respectively. PYC exerted strong scavenging activities against reactive oxygen species (ROS) generated by H2O2 in RAW 264.7. In situ ELISA, immunoblot analysis, and competitive RT-PCR demonstrated that pretreatment of LPS-stimulated RAW 264.7 cells with PYC dose-dependently reduced both the production of IL-1beta and its mRNA levels. Furthermore, in the same cells, PYC blocked the activation of nuclear factor kappaB (NF-kappaB) and activator protein-1 (AP-1), two major transcription factors centrally involved in IL-1beta gene expression. Concordantly, pretreatment of the cells with PYC abolished the LPS-induced IkappaB degradation. We also investigated the effect of PYC on IL-2 gene expression in phorbol 12-myristate 13acetate plus ionomycin (PMA/Io)-stimulated human T-cell line Jurkat E6.1. PYC inhibited the PMA/Io-induced IL-2 mRNA expression. However, as demonstrated in a reporter gene assay system, the mechanism of IL-2 gene transcriptional regulation by PYC was different from the regulation of IL-1beta. PYC inhibited both NF-AT and AP-1 chloramphenicol acetyltransferase (CAT) activities in transiently transfected Jurkat E6.1, but not NF-kappaB CAT activity. We also found that PYC can destabilize PMA/Io-induced IL-2 mRNA by posttranscriptional regulation. All these results suggest that bioflavonids can be useful therapeutic agents in treating many inflammatory, autoimmune, and cardiovascular diseases based on its diverse action mechanisms.

Prolactin-inducible enhancer activity of the first intron of the bovine beta-casein gene.

We have analyzed the regulatory roles of the first intron (intron-1) of the bovine beta-casein gene in the bovine beta-casein/CAT expression system using a mouse mammary epithelial cell line, HC11. After a combined treatment of HC11 cells with insulin, dexamethasone and prolactin, the induced expression of p beta c1.8/+ICAT vector including 2 kb intron-1 and 1.8 kb promoter was greatly increased to 23.5 folds, while that of p beta ca.8CAT basic vector with 1.8 kb promoter only, was 6.5. A classical enhancer activity was shown in the 2 kb intron fragment from the experiment in which the orientation and the position of the intron-1 on the vectors were changed. The enhancer activity was largely dependent on the lactogenic hormones, especially prolactin. A stepwise reduction of the inducibility in the 5' to 3' deletion analysis of the intron-1 indicates the existence of several functional elements in the region. In particular, an internal fragment (+1071 to +1490) was important for the prolactin-dependent enhancing activity of the intron-1. These results suggest that several elements in the intron-1 of the bovine beta-casein gene cooperatively interact not only with each other but also with its promoter for hormonal induction.

Inhibitory effect of hemin on mutagenicity of the electrophilic sulfuric acid ester of 6-hydroxymethylbenzo[a]pyrene.

In the present study, we examined the effects of hemin on the mutagenicity of 6-sulfooxymethylbenzo[a]pyrene (SMBP) in Salmonella typhimurium TA98 and Chinese hamster lung fibroblast (V79) cells. The compound was tested for the possible chemoprotective activity against mutagenesis induced by SMBP and its precursor, 6-hydroxymethylbenzo[a]pyrene (HMBP), activated by hepatic cytosol and PAPS in S. typhimurium TA98. Hemin not only inhibited the mutagenic activity of SMBP in V79 cells but repressed the cytotoxicity induced by this reactive ester as demonstrated by increased cell growth. The intracellular accumulation of radioactivity in V79 cells exposed to [3H]SMBP was reduced by approximately 50% when hemin (10 microM) was added to the medium. Likewise, the formation of SMBP-DNA adducts in these cells was significantly attenuated by treatment with hemin. The covalent complex formation of hemin with SMBP was confirmed by solvent extraction and reverse-phase HPLC.

Mutagenicity of 6-sulfooxymethylbenzo[a]pyrene in Salmonella typhimurium and Chinese hamster V79 cells.

6-Sulfooxymethylbenzo[a]pyrene (SMBP) is an ultimate and reactive form of 6-hydroxymethybenzo[a]pyrene (HMBP), which is converted into SMBP by the mediation of sulfotransferase. SMBP and HMBP with metabolic activation were mutagenic to S. typhimurium TA98 and TA100. The number of mutation per plate in strain TA98 was proportional to the concentrations of SMBP ranging from 0.2 to 1.0 nmol/plate, whereas that in strain TA100 was decreased at concentrations above 0.6 nmol/plate. The mutation frequencies by HMBP was also increased in a dose dependent manner in both strains. Furthermore, SMBP and HMBP were highly mutagenic and cytotoxic to Chinese hamster lung fibroblast (V79) cells. A dose-dependent increase in mutation frequencies at both hypoxanthine:guanine phosphoribosyltransferase (HGPRT) and sodium/potassium-ATPase (Na/K-ATPase) loci were found in V79 cells treated with SMBP and HMBP. The cytotoxicity of SMBP was increased with the increasing concentrations up to 2.5 microM, where the survival frequency and growth rate were decreased to almost 40% and 30% of the control value, respectively. The survival frequencies of V79 cells by HMBP were also decreased in a dose dependent manner up to 180 microM as similar to those of SMBP but the effects were less remarkable. SMBP was progressively accumulated in V79 cells, reaching plateau in just 30 min. A dose dependent increase in complex formation with DNA or proteins was observed by treatment with SMBP. The mutagenicity and cytotoxicity of SMBP and HMBP may be derived from their binding capacity to DNA in V79 cells and S. typhimurium.

Intracoronary stent implantation in Jamaica. The initial experience.

Intracoronary stent implantation resulted in the complete or near complete dilatation of high grade occlusions of the left anterior descending coronary arteries in the four patients in whom it was undertaken. Intracoronary stent implantation is a useful adjunct to Percutaneous Transluminal Angioplasty (PTCA) and is applicable in selected patients with symptomatic ischaemic heart disease in a developing country with limited health resources like Jamaica. This is so since financial data presented here document the significant savings this technique (when appropriately utilised) could realise compared to the use of balloon angioplasty alone.

Percutaneous balloon mitral valvuloplasty for severe rheumatic mitral stenosis in Jamaica: the initial experience.

Although percutaneous balloon mitral valvuloplasty has been performed in the Caribbean before, there has not been any detailed description in the English-speaking West Indian Medical literature hitherto. This report provides a description of the first four cases of percutaneous balloon mitral valvuloplasty performed in Jamaica.

Influence of oral administration of estradiol-17ß and testosterone on growth, digestion, food conversion and metabolism in the underyearling red sea bream, Chrysophrys major.

Estradiol-17ß (E2) administered in the diet to the red sea bream Chrysophrys major did not affect appetite, food conversion efficiency, protein efficiency ratio and specific growth rate. Serum concentrations of total protein, albumin, globulin, vitellogenin, α-amino acids, total lipid, free fatty acids, cholesterol and calcium were elevated. The hepatosomatic index was also increased. Activities of hepatic enzymes including lactate dehydrogenase, isocitrate dehydrogenase and glutamate-pyruvate transaminase were higher than found in untreated control fish. Intestinal activity of leucine aminopeptidase was augmented. However, there were no changes in muscle water, protein, lipid and glycogen content. In contrast, testosterone (T) given by the same route increased appetite, food conversion efficiency, protein efficiency ratio and specific growth rate. There were no alterations in serum protein and calcium concentrations but serum glucose, ammonia and triglyceride levels were elevated. Hepatic glycogen content was increased. The activities of hepatic fructose- 1,6-diphosphatase, glucose-6-phosphatase and glycogen synthetase and intestinal activities of alkaline phosphatase and τ-glutamyltransferase were higher than noted on control fish. The results reveal that estradiol-17ß and testosterone exerted different metabolic effects in the red sea bream and they suggest that testosterone exerts its anabolic actions by increasing appetite, food conversion efficiency and activities of digestive enzymes.

Inhibitory effect of selenite on invasion of HT1080 tumor cells.

Selenium, an essential biological trace element, has been shown to reduce and prevent the incidence of cancer. Our previous studies have shown that selenite is involved in the chemoprevention of cancer and induction of apoptosis of cancer cells. In this study, we demonstrate that selenite also inhibits the invasion of tumor cells. Cancer cell invasion requires coordinated processes, such as changes in cell-cell and cell-matrix adhesion, degradation of the extracellular matrix, and cell migration. We found that selenite inhibited invasion of HT1080 human fibrosarcoma cells. Adhesion of HT1080 cells to the collagen matrix was also inhibited by treatment with selenite, but cell-cell interaction and cell motility were not affected by selenite. Moreover, selenite reduced expression of matrix metalloproteinase-2 and -9 and urokinase-type plasminogen activator, which are involved in matrix degradation, but increased a tissue inhibitor of metalloproteinase-1. This inhibitory effect of selenite on the protease expressions was mediated by the suppression of transcription factors, NF-kappaB and AP-1. However, selenate showed no remarkable effect on all the steps of cancer cell invasion.

Induction of apoptosis by selenite and selenodiglutathione in HL-60 cells: correlation with cytotoxicity.

Effects of selenite and selenodiglutathione, an initial metabolite of selenite, on the induction of apoptosis and cytotoxicity were investigated in human promyelocytic leukemia HL-60 cells. Treatment of selenite or selenodiglutathione resulted in concentration-dependent cytotoxicity, measured by lactate dehydrogenase leakage assay, and by tetrazolium salt reduction assay. Selenodiglutathione has been shown to exert more cytotoxic effect than selenite in both assay systems. Time-course study of cellular selenium uptake suggests that the higher cytotoxicity of selenodiglutathione be largely due to faster and greater selenium uptake rate. Treatment with selenite or selenodiglutathione also induced apoptosis in a dose-dependent manner, as detected by enzyme-linked immunosorbent assay and by DNA fragmentation assay. The dose-response data of apoptosis induced by selenite or selenodiglutathione were similar to those of cytotoxicity, implicating a relationship between the induction of apoptosis and cytotoxicity. Zn, which is a well-known inhibitor of apoptosis, dose-dependently blocked not only the induction of apoptosis, but also the membrane damage induced by selenium, corroborating this hypothesis. It was noted that the inhibition of apoptosis by Zn exerted little protective effect on cytotoxicity at higher concentrations of selenium, compared with a perfect protective effect at low concentration of selenium. These results suggest that cytotoxicity induced by selenium may be partially correlated with apoptosis.

Se-methylselenocysteine induces apoptosis through caspase activation in HL-60 cells.

Apoptosis, a programmed process of cell suicide, has been proposed as the most plausible mechanism for the chemopreventive activities of selenocompounds. In our study, we found that Se-methylselenocysteine (MSC) induced apoptosis through caspase activation in human promyelocytic leukemia (HL-60) cells. Measurements of cytotoxicity, DNA fragmentation and apoptotic morphology revealed that MSC was more efficient at inducing apoptosis than selenite, but was less toxic. Moreover, MSC increased both the apoptotic cleavage of poly(ADP-ribose) polymerase (PARP) and caspase-3 activity, whereas selenite did not. We next examined whether caspases and serine proteases are required for the apoptotic induction by MSC. A general caspase inhibitor, z-VAD-fmk, dramatically decreased cytotoxicity in MSC-treated HL-60 cells and several other apoptotic features, such as, caspase-3 activation, the apoptotic DNA ladder, TUNEL-positive staining and the DNA double-strand break. Interestingly, a general serine protease inhibitor, AAPV-cmk, also effectively inhibited MSC-mediated cytotoxicity and apoptosis. These results demonstrate that MSC is a selenocompound that efficiently induces apoptosis in leukemia cells and that proteolytic machinery, in particular caspase-3, is necessary for MSC-induced apoptosis. On the other hand, selenite-induced cell death could be derived from necrosis rather than apoptosis, since selenite did not significantly induce several apoptotic phenomena, including the activation of caspase-3.