Emerging tobacco hazards in China: 1. Retrospective proportional mortality study of one million deaths

OBJECTIVE

To assess the hazards at an early phase of the growing epidemic of deaths from tobacco in China.

DESIGN

Smoking habits before 1980 (obtained from family or other informants) of 0.7 million adults who had died of neoplastic, respiratory, or vascular causes were compared with those of a reference group of 0.2 million who had died of other causes.

SETTING

24 urban and 74 rural areas of China.

SUBJECTS

One million people who had died during 1986-8 and whose families could be interviewed.

MAIN OUTCOME MEASURES

Tobacco attributable mortality in middle or old age from neoplastic, respiratory, or vascular disease.

RESULTS

Among male smokers aged 35-69 there was a 51% (SE 2) excess of neoplastic deaths, a 31% (2) excess of respiratory deaths, and a 15% (2) excess of vascular deaths. All three excesses were significant (P<0.0001). Among male smokers aged >/70 there was a 39% (3) excess of neoplastic deaths, a 54% (2) excess of respiratory deaths, and a 6% (2) excess of vascular deaths. Fewer women smoked, but those who did had tobacco attributable risks of lung cancer and respiratory disease about the same as men. For both sexes, the lung cancer rates at ages 35-69 were about three times as great in smokers as in non-smokers, but because the rates among non-smokers in different parts of China varied widely the absolute excesses of lung cancer in smokers also varied. Of all deaths attributed to tobacco, 45% were due to chronic obstructive pulmonary disease and 15% to lung cancer; oesophageal cancer, stomach cancer, liver cancer, tuberculosis, stroke, and ischaemic heart disease each caused 5-8%. Tobacco caused about 0.6 million Chinese deaths in 1990 (0.5 million men). This will rise to 0.8 million in 2000 (0.4 million at ages 35-69) or to more if the tobacco attributed fractions increase.

CONCLUSIONS

At current age specific death rates in smokers and non-smokers one in four smokers would be killed by tobacco, but as the epidemic grows this proportion will roughly double. If current smoking uptake rates persist in China (where about two thirds of men but few women become smokers) tobacco will kill about 100 million of the 0.3 billion males now aged 0-29, with half these deaths in middle age and half in old age.

Risk factors for surgical site infection after elective resection of the colon and rectum: a single-center prospective study of 2,809 consecutive patients

OBJECTIVE

To identify the risk factors for surgical site infection (SSI) in patients undergoing elective resection of the colon and rectum.

SUMMARY BACKGROUND DATA

SSI causes a substantial number of deaths and complications. Determining risk factors for SSI may provide information on reducing complications and improving outcome.

METHODS

The authors performed a prospective study of 2,809 consecutive patients undergoing elective colorectal resection via laparotomy between February 1995 and December 1998 at a single institution. The outcome of interest was SSI, which was classified as being incisional or organ/space with or without clinical leakage. A likelihood ratio forward regression model was used to assess the independent association of variables with SSIs.

RESULTS

The overall SSI, incisional SSI, and organ/space SSI with and without clinical anastomotic leakage rates were 4.7%, 3%, 2%, and 0.8%, respectively. Risk factors for overall SSI were American Society of Anesthesiology (ASA) score 2 or 3 (odd ratio [OR] = 1.7), male gender (OR = 1.5), surgeons (OR = 1.3-3.3), types of operation (OR = 0.3-2.1), creation of ostomy (OR = 2.1), contaminated wound (OR = 2.9), use of drainage (OR = 1.6), and intra- or postoperative blood transfusion (1-3 units, OR = 5.3; >/=4 units, OR = 6.2). However, SSIs at specific sites differed from each other with respect to the risk factors. Among a variety of risk factors, only blood transfusion was consistently associated with a risk of SSI at any specific site.

CONCLUSIONS

In addition to ASA score and surgical wound class, blood transfusion, creation of ostomy, types of operation, use of drainage, sex, and surgeons were important in predicting SSIs after elective colorectal resection.

Autoradiographic demonstration of increased serotonin 5-HT2 and beta-adrenergic receptor binding sites in the brain of suicide victims

Suicidal behavior has been linked to a deficiency in serotonin neurotransmission, but it is not known which brain regions are involved. We determined the pattern of alteration in serotonin 5-HT2 (5-HT2) receptor binding sites in suicide victims in prefrontal cortex compared with temporal cortex using a matched-pairs design to study 11 suicide victims and 11 matched controls, by both membrane binding and quantitative receptor autoradiography. Since a relationship between the serotonergic and noradrenergic systems has been proposed, we also examined beta-adrenergic receptor binding sites. Binding to 5-HT2 and beta-adrenergic sites in slide-mounted sections correlated strongly with binding site number in membrane preparations. A specific laminar distribution of 5-HT2 binding sites was found in both the control and suicide groups, whereas beta-adrenergic binding sites did not differ across cortical layers. A significant increase was found in suicide victims across all cortical layers in both receptor subpopulations in the prefrontal cortex, but only beta-adrenergic sites were increased in the temporal cortex. We conclude that suicide is associated with a localized increase in 5-HT2 binding sites.

Models of care for the secondary prevention of osteoporotic fractures: a systematic review and meta-analysis

Most people presenting with incident osteoporotic fractures are neither assessed nor treated for osteoporosis to reduce their risk of further fractures, despite the availability of effective treatments. We evaluated the effectiveness of published models of care for the secondary prevention of osteoporotic fractures. We searched eight medical literature databases to identify reports published between 1996 and 2011, describing models of care for secondary fracture prevention. Information extracted from each publication included study design, patient characteristics, identification strategies, assessment and treatment initiation strategies, as well as outcome measures (rates of bone mineral density (BMD) testing, osteoporosis treatment initiation, adherence, re-fractures and cost-effectiveness). Meta-analyses of studies with valid control groups were conducted for two outcome measures: BMD testing and osteoporosis treatment initiation. Out of 574 references, 42 articles were identified as analysable. These studies were grouped into four general models of care-type A: identification, assessment and treatment of patients as part of the service; type B: similar to A, without treatment initiation; type C: alerting patients plus primary care physicians; and type D: patient education only. Meta-regressions revealed a trend towards increased BMD testing (p = 0.06) and treatment initiation (p = 0.03) with increasing intensity of intervention. One type A service with a valid control group showed a significant decrease in re-fractures. Types A and B services were cost-effective, although definition of cost-effectiveness varied between studies. Fully coordinated, intensive models of care for secondary fracture prevention are more effective in improving patient outcomes than approaches involving alerts and/or education only.

3-Hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors. 4. Side chain ester derivatives of mevinolin

Modification of the 2(S)-methylbutyryl moiety of mevinolin led to a series of side chain ester derivatives. A systematic exploration of the structure-activity relationships showed that the introduction of an additional aliphatic group on the carbon alpha to the carbonyl group increased potency. This observation led to the synthesis of compound 16, which has about 2.5 times the intrinsic inhibitory activity of mevinolin.

Proteogenomics of Non-smoking Lung Cancer in East Asia Delineates Molecular Signatures of Pathogenesis and Progression

Lung cancer in East Asia is characterized by a high percentage of never-smokers, early onset and predominant EGFR mutations. To illuminate the molecular phenotype of this demographically distinct disease, we performed a deep comprehensive proteogenomic study on a prospectively collected cohort in Taiwan, representing early stage, predominantly female, non-smoking lung adenocarcinoma. Integrated genomic, proteomic, and phosphoproteomic analysis delineated the demographically distinct molecular attributes and hallmarks of tumor progression. Mutational signature analysis revealed age- and gender-related mutagenesis mechanisms, characterized by high prevalence of APOBEC mutational signature in younger females and over-representation of environmental carcinogen-like mutational signatures in older females. A proteomics-informed classification distinguished the clinical characteristics of early stage patients with EGFR mutations. Furthermore, integrated protein network analysis revealed the cellular remodeling underpinning clinical trajectories and nominated candidate biomarkers for patient stratification and therapeutic intervention. This multi-omic molecular architecture may help develop strategies for management of early stage never-smoker lung adenocarcinoma.

MicroRNA-519c suppresses hypoxia-inducible factor-1alpha expression and tumor angiogenesis

Hypoxia-inducible factor-1alpha (HIF-1alpha) is widely considered to be one of the key regulators of tumor angiogenesis. The upstream regulation is complex and involves several growth factors, cytokines, and hypoxia. Herein, we have identified miR-519c as a hypoxia-independent regulator of HIF-1alpha, acting through direct binding to the HIF-1alpha 3' untranslated region and leading to reduced tumor angiogenesis. Overexpression of miR-519c resulted in a significant decrease of HIF-1alpha protein levels and reduced the tube formation of human umbilical vein endothelial cells; similarly, antagomir inhibition of miR-519c increased the level of HIF-1alpha protein and enhanced angiogenic activity, suggesting an important role of miR-519c in HIF-1alpha-mediated angiogenesis. Consistent with the overexpression of miR-519c in cancer patients with better prognosis, mice injected with miR-519c-overexpressing cells exhibited dramatically reduced HIF-1alpha levels, followed by suppressed tumor angiogenesis, growth, and metastasis. In addition, we found that hepatocyte growth factor (HGF), a known HIF-1alpha inducer, reduced the miR-519c levels through an Akt-dependent pathway. This regulation was posttranscriptional and may be mediated by suppression of miR-519c maturation. Taken together, our findings provide the first evidence that miR-519c is a pivotal regulator of tumor angiogenesis and that microenvironmental HGF contributes to regulating miR-519c biogenesis in cancer cells.

Chronic alterations in dopaminergic neurotransmission produce a persistent elevation of deltaFosB-like protein(s) in both the rodent and primate striatum

Using an antibody that recognizes the products of all known members of the fos family of immediate early genes, it was demonstrated that destruction of the nigrostriatal pathway by 6-hydroxydopamine (6-OHDA) lesions of the medial forebrain bundle produces a prolonged (>3 months) elevation of Fos-like immunoreactivity in the striatum. Using retrograde tract tracing techniques, we have previously shown that this increase in Fos-like immunoreactivity is located predominantly in striatal neurons that project to the globus pallidus. In the present study, Western blots were performed on nuclear extracts from the intact and denervated striatum of 6-OHDA-lesioned rats to determine the nature of Fos-immunoreactive protein(s) responsible for this increase. Approximately 6 weeks after the 6-OHDA lesion, expression of two Fos-related antigens with apparent molecular masses of 43 and 45 kDa was enhanced in the denervated striatum. Chronic haloperidol administration also selectively elevated expression of these Fos-related antigens, suggesting that their induction after dopaminergic denervation is mediated by reduced activation of D2-like dopamine receptors. Western blot immunostaining using an antibody which recognizes the N-terminus of FosB indicated that the 43 and 45 kDa Fos-related antigens induced by dopaminergic denervation and chronic haloperidol administration may be related to a truncated form of FosB known as deltaFosB. Consistent with this proposal, retrograde tracing experiments confirmed that deltaFosB-like immunoreactivity in the deafferented striatum was located predominantly in striatopallidal neurons. Gel shift experiments demonstrated that elevated AP-1 binding activity in denervated striata contained FosB-like protein(s), suggesting that enhanced deltaFosB levels may mediate some of the effects of prolonged dopamine depletion on AP-1-regulated genes in striatopallidal neurons. In contrast, chronic administration of the D1-like receptor agonist CY 208243 to 6-OHDA-lesioned rats dramatically enhanced deltaFosB-like immunoreactivity in striatal neurons projecting to the substantia nigra. Western blot immunostaining revealed that deltaFosB and, to a lesser extent, FosB are elevated by chronic D1-like agonist administration. Both the quantitative reverse transcriptase-polymerase chain reaction and the ribonuclease protection assay demonstrated that deltafosB mRNA levels were substantially enhanced in the denervated striatum by chronic D1-like agonist administration. Lastly, we examined the effects of chronic administration ofD1-like and D2-like dopamine receptor agonists on striatal deltaFosB expression in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) primate model of Parkinson's disease. In monkeys rendered Parkinsonian by MPTP, there was a modest increase in deltaFosB-like protein(s), while the development of dyskinesia produced by chronic D1-like agonist administration was accompanied by large increases in DeltaFosB-like protein(s). In contrast, administration of the long-acting D2-like agonist cabergoline, which alleviated Parkinsonian symptoms without producing dyskinesia reduced deltaFosB levels to near normal. Taken together, these results demonstrate that chronic alterations in dopaminergic neurotransmission produce a persistent elevation of deltaFosB-like protein(s) in both the rodent and primate striatum.

Mosquito cathepsin B-like protease involved in embryonic degradation of vitellin is produced as a latent extraovarian precursor

Here we report identification of a novel member of the thiol protease superfamily in the yellow fever mosquito, Aedes aegypti. It is synthesized and secreted as a latent proenzyme in a sex-, stage-, and tissue-specific manner by the fat body, an insect metabolic tissue, of female mosquitoes during vitellogenesis in response to blood feeding. The secreted, hemolymph form of the enzyme is a large molecule, likely a hexamer, consisting of 44-kDa subunits. The deduced amino acid sequence of this 44-kDa precursor shares high similarity with cathepsin B but not with other mammalian cathepsins. We have named this mosquito enzyme vitellogenic cathepsin B (VCB). VCB decreases to 42 kDa after internalization by oocytes. In mature yolk bodies, VCB is located in the matrix surrounding the crystalline yolk protein, vitellin. At the onset of embryogenesis, VCB is further processed to 33 kDa. The embryo extract containing the 33-kDa VCB is active toward benzoyloxycarbonyl-Arg-Arg-para-nitroanilide, a cathepsin B-specific substrate, and degrades vitellogenin, the vitellin precursor. Both of these enzymatic activities are prevented by trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane (E-64), a thiol protease inhibitor. Furthermore, addition of the anti-VCB antibody to the embryonic extract prevented cleavage of vitellogenin, strongly indicating that the activated VCB is involved in embryonic degradation of vitellin.

Serum albumin adducts in the molecular epidemiology of aflatoxin carcinogenesis: correlation with aflatoxin B1 intake and urinary excretion of aflatoxin M1

Aflatoxin-serum albumin adducts in the blood of 42 residents of Guangxi Province, People's Republic of China, were determined and compared with intake of aflatoxin B1 (AFB1) and excretion of aflatoxin M1 (AFM1) in urine. Blood specimens were obtained during the same period that urine was collected and that diet was sampled. Serum albumin was isolated from blood by affinity chromatography on Reactive Blue 2-Sepharose and subjected to enzymatic proteolysis using Pronase. Immunoreactive products were purified by immunoaffinity chromatography and quantified by competitive radioimmunoassay. A highly significant correlation (r = 0.60, P less than 0.00003) of adduct level with AFM1 excretion was observed. An equally highly significant correlation of adduct level with intake (r = 0.69, P less than 0.000001) was also observed. From the slope of the regression line for adduct level as a function of intake, it was calculated that 1.4-2.3% of ingested AFB1 becomes covalently bound to serum albumin, a value very similar to that observed when rats are administered AFB1.

Tissue transglutaminase: an enzyme with a split personality

Tissue transglutaminase (tTG) belongs to the family of transglutaminase enzymes that catalyze the posttranslational modification of proteins via Ca(2+)-dependent cross-linking reactions. The catalytic action of tTG results in the formation of an isopeptide bond that is of great physiological significance since it is highly resistant to proteolysis and denaturants. Although tTG-mediated cross-linking reactions have been implicated to play a role in diverse biological processes, the precise physiological function of the enzyme remains unclear. Recent data, however, suggest that the protein polymers resulting from tTG-catalyzed reactions may play a role in commitment of cells to undergo apoptosis. On the same token, tTG-mediated formation of insoluble protein aggregates may underlie the markers of numerous pathological conditions, such as the senile plaques in Alzheimer's disease and the Lewy bodies in Parkinson's disease. In addition to catalyzing Ca(2+)-dependent cross-linking reactions, tTG can also bind and hydrolyze guanosine triphosphate and adenosine triphosphate. By virtue of this ability, tTG has been identified as a novel G-protein that interacts and activates phospholipase C following stimulation of the alpha-adrenergic receptor. The ability of tTG to mediate signal transduction may contribute to its involvement in the regulation of cell cycle progression. The following review summarizes the important features of this multifunctional enzyme that have emerged as a result of recent work from different laboratories.

Extensive sequence conservation among insect, nematode, and vertebrate vitellogenins reveals ancient common ancestry

The eggs of most oviparous animals are provisioned with a class of protein called vitellogenin (Vg) which is stored as the major component of yolk. Until recently, deduced amino acid sequences were available only from vertebrate and nematode Vgs, which proved to be homologous. The sequences of several insect Vgs are now known, but early attempts at pairwise alignments with vertebrate and nematode Vgs have been problematic, leading to conflicting conclusions about how closely insect Vgs are related to the others. In this paper we demonstrate that insect Vg sequences can be confidently aligned with one another along their entire lengths and with multiple vertebrate and nematode Vg sequences along most of their spans. Although divergence is high, conservation among insect, vertebrate, and nematode Vg sequences is widespread with a preponderance of glycine, proline, and cysteine residues among strictly conserved amino acids, establishing conclusively that Vgs from the three phyla are homologous. Areas of least-certain alignment are primarily in and around insect and vertebrate polyserine domains which are not homologous. Phylogenetic reconstructions of Vgs based on sequence identities indicate that the insect lineage is the most diverged and that the mammalian serum protein, apolipoprotein B-100, arose from a Vg ancestor after the nematode/vertebrate divergence.

Phosphorylation/cytoplasmic localization of p21Cip1/WAF1 is associated with HER2/neu overexpression and provides a novel combination predictor for poor prognosis in breast cancer patients

PURPOSE

The diversity of biological functions makes p21(Cip1/WAF1) (p21) a controversial marker in predicting the prognosis of breast cancer patients. Recent laboratory studies revealed that the regulation of p21 function could be related to different subcellular localizations of p21 by Akt-induced phosphorylation at threonine 145 in HER2/neu-overexpressing breast cancer cells. The purpose of this study was to verify these findings in clinical settings.

EXPERIMENTAL DESIGN

The expression status of the key biological markers in the HER2/neu-Akt-p21 pathway in 130 breast cancer specimens was evaluated by immunohistochemical staining and correlated with patients' clinical parameters and survival. In addition, an antibody against phospho-p21 at threonine 145 [phospho-p21 (T145)] was also used for better validation of these findings.

RESULTS

Cytoplasmic localization of p21 is highly correlated with overexpression of phospho-p21 (T145). Both cytoplasmic p21 and overexpression of phospho-p21 (T145) are associated with high expression of HER2/neu and phospho-Akt. Cytoplasmic localization of p21 and overexpression of phospho-p21 (T145), HER2/neu, and phospho-Akt are all associated with worse overall survival. Multivariate analysis of the Cox proportional hazard regression model revealed that cytoplasmic p21 and overexpression of HER2/neu are independently associated with increased risk of death. Combining these two factors stratified patients' survival into four distinct groups, with a 5-year survival rate of 79% in low HER2/neu and negative/nuclear p21 patients, 60% in high HER2/neu and negative/nuclear p21 patients, 29% in low HER2/neu and cytoplasmic p21 patients, and 16% in high HER2/neu and cytoplasmic p21 patients.

CONCLUSIONS

The present study, in addition to supporting the mechanisms of p21 regulation derived from laboratory investigation, demonstrates the prognostic importance of phospho-p21 (T145) for the first time and also provides a novel combination of p21 and HER2/neu for better stratification of patients' survival than any single clinicopathological or biological marker that may play important diagnostic and therapeutic roles for breast cancer patients.

Identification of novel markers for monitoring minimal residual disease in acute lymphoblastic leukemia

To identify new markers of minimal residual disease (MRD) in B-lineage acute lymphoblastic leukemia (ALL), gene expression of leukemic cells obtained from 4 patients with newly diagnosed ALL was compared with that of normal CD19(+)CD10(+) B-cell progenitors obtained from 2 healthy donors. By cDNA array analysis, 334 of 4132 genes studied were expressed 1.5- to 5.8-fold higher in leukemic cells relative to both normal samples; 238 of these genes were also overexpressed in the leukemic cell line RS4;11. Nine genes were selected among the 274 overexpressed in at least 2 leukemic samples, and expression of the encoded proteins was measured by flow cytometry. Two proteins (caldesmon and myeloid nuclear differentiation antigen) were only weakly expressed in leukemic cells despite strong hybridization signals in the array. By contrast, 7 proteins (CD58, creatine kinase B, ninjurin1, Ref1, calpastatin, HDJ-2, and annexin VI) were expressed in B-lineage ALL cells at higher levels than in normal CD19(+)CD10(+) B-cell progenitors (P <.05 in all comparisons). CD58 was chosen for further analysis because of its abundant and prevalent overexpression. An anti-CD58 antibody identified residual leukemic cells (0.01% to 1.13%; median, 0.03%) in 9 of 104 bone marrow samples from children with ALL in clinical remission. MRD estimates by CD58 staining correlated well with those of polymerase chain reaction amplification of immunoglobulin genes. These results indicate that studies of gene expression with cDNA arrays can aid the discovery of leukemia markers. (Blood. 2001;97:2115-2120)

miR-107 promotes tumor progression by targeting the let-7 microRNA in mice and humans

MicroRNAs (miRNAs) influence many biological processes, including cancer. They do so by posttranscriptionally repressing target mRNAs to which they have sequence complementarity. Although it has been postulated that miRNAs can regulate other miRNAs, this has never been shown experimentally to our knowledge. Here, we demonstrate that miR-107 negatively regulates the tumor suppressor miRNA let-7 via a direct interaction. miR-107 was found to be highly expressed in malignant tissue from patients with advanced breast cancer, and its expression was inversely correlated with let-7 expression in tumors and in cancer cell lines. Ectopic expression of miR-107 in human cancer cell lines led to destabilization of mature let-7, increased expression of let-7 targets, and increased malignant phenotypes. In contrast, depletion of endogenous miR-107 dramatically increased the stability of mature let-7 and led to downregulation of let-7 targets. Accordingly, miR-107 expression increased the tumorigenic and metastatic potential of a human breast cancer cell line in mice via inhibition of let-7 and upregulation of let-7 targets. By mutating individual sites within miR-107 and let-7, we found that miR-107 directly interacts with let-7 and that the internal loop of the let-7/miR-107 duplex is critical for repression of let-7 expression. Altogether, we have identified an oncogenic role for miR-107 and provide evidence of a transregulational interaction among miRNAs in human cancer development.

Effects of age and gender on CNS serotonergic responsivity in normal adults

The effects of age and gender on central nervous system (CNS) serotonergic responsivity were assessed with a neuroendocrine challenge test in 30 normal adults. Subjects greater than or equal to 30 years of age, compared with younger subjects, exhibited decreased prolactin secretion in response to a 60-mg oral dose of dl-fenfluramine hydrochloride, an indirect serotonin agonist. Furthermore, women had greater prolactin responses than men. As prolactin secretory capacity appears to be stable through midlife, the age-associated decrease in fenfluramine-induced prolactin release suggests a decline in CNS serotonergic responsivity. In contrast, the finding of greater prolactin release in women than in men probably reflects the effects of nonserotonergic modulatory influences at the level of the lactotroph. Age and gender effects must be considered in studies of the CNS serotonergic system.

Phase II study of gemcitabine in patients with advanced hepatocellular carcinoma

BACKGROUND

The objective of this study was to evaluate the efficacy and toxicity of gemcitabine in patients with chemotherapy-naïve, advanced hepatocellular carcinoma (HCC).

METHODS

Twenty-eight patients with unresectable and nonembolizable HCC who had received no prior systemic chemotherapy and with objectively measurable tumors, adequate liver and renal function, and adequate bone marrow reserve were enrolled on this study. The therapy consisted of gemcitabine 1250 mg/m(2) intravenously over 30 minutes weekly in an outpatient clinic. One course of treatment included three consecutive weekly infusions of gemcitabine and a 1-week rest. Treatment courses were repeated every 4 weeks for a total of six courses unless there was prior evidence of progressive disease.

RESULTS

All 28 patients were evaluable for response and toxicity. A partial response (PR) was achieved in 5 patients, for an overall response rate of 17.8% (95% confidence interval, 2.7-32.9%). Seven patients had stable disease (25%), and 16 patients had disease progression (57.2%). The median survival for all 28 patients was 18. 7 weeks, and, for those patients who achieved a PR, it was 34.7 weeks. The median time to progression was 12 weeks. National Cancer Institute Common Toxicity Criteria Grade 3-4 toxicity consisted primarily of leucopenia (10.7%), anemia (14.3%), thrombocytopenia (10.7%), and hepatotoxicity (14.3%). The spectrum of both hematologic and nonhematologic toxicity was mild, with thrombocytopenia constituting the dose-limiting side effect.

CONCLUSIONS

Gemcitabine shows marginal antitumor activity in patients with advanced HCC, although the response duration is short-lived. Gemcitabine seems to be particularly promising because of its low toxicity profile. Further studies in combination with other active agents are warranted.

The global burden attributable to low bone mineral density

INTRODUCTION

The Global Burden of Disease Study 2010 estimated the worldwide health burden of 291 diseases and injuries and 67 risk factors by calculating disability-adjusted life years (DALYs). Osteoporosis was not considered as a disease, and bone mineral density (BMD) was analysed as a risk factor for fractures, which formed part of the health burden due to falls.

OBJECTIVES

To calculate (1) the global distribution of BMD, (2) its population attributable fraction (PAF) for fractures and subsequently for falls, and (3) the number of DALYs due to BMD.

METHODS

A systematic review was performed seeking population-based studies in which BMD was measured by dual-energy X-ray absorptiometry at the femoral neck in people aged 50 years and over. Age- and sex-specific mean ± SD BMD values (g/cm(2)) were extracted from eligible studies. Comparative risk assessment methodology was used to calculate PAFs of BMD for fractures. The theoretical minimum risk exposure distribution was estimated as the age- and sex-specific 90th centile from the Third National Health and Nutrition Examination Survey (NHANES III). Relative risks of fractures were obtained from a previous meta-analysis. Hospital data were used to calculate the fraction of the health burden of falls that was due to fractures.

RESULTS

Global deaths and DALYs attributable to low BMD increased from 103 000 and 3 125 000 in 1990 to 188 000 and 5 216 000 in 2010, respectively. The percentage of low BMD in the total global burden almost doubled from 1990 (0.12%) to 2010 (0.21%). Around one-third of falls-related deaths were attributable to low BMD.

CONCLUSIONS

Low BMD is responsible for a growing global health burden, only partially representative of the real burden of osteoporosis.

Carotid sinus baroreceptor sensitivity in experimental heart failure

Single-unit carotid sinus baroreceptor activity was recorded in normal and heart-failure (pacing-induced) dogs. The sensitivity of these units was compared between the two groups of dogs. After development of clinical heart failure, the animals were anesthetized, and the left carotid sinus was vascularly isolated and perfused with oxygenated Krebs-Henseleit solution. Single-unit baroreceptor discharge was recorded from the carotid sinus nerve in response to stepwise increases in carotid sinus pressure (CSP). In addition, the carotid sinus diameter was measured with sonomicrometer crystals. In this way, both CSP-discharge and CSP-diameter curves were constructed for both normal and heart-failure dogs. Analysis of these curves demonstrated that the heart-failure group exhibited a significant decrease in peak discharge (48.1 +/- 3.0 vs. 22.2 +/- 2.2 spikes/sec; p less than 0.001) and a significant elevation in threshold pressure compared with the normal animals (91.0 +/- 5.0 vs. 119.1 +/- 4.4 mm Hg; p less than 0.001). The peak slope of the CSP-discharge curve was also significantly lower in the heart-failure group (0.63 +/- 0.06 vs. 0.40 +/- 0.09 spikes/sec/mm Hg; p less than 0.05). In the heart-failure group, perfusion of the carotid sinus with ouabain (0.01 micrograms/ml) caused a significant decrease in threshold pressure and a significant increase in peak discharge frequency, as well as an increase in slope of the CSP-discharge curve. There were no changes in CSP-diameter relations in response to ouabain. This dose of ouabain had no effect on pressure-discharge relations or carotid sinus diameters in normal dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Endemicity and inter-city spread of Burkholderia cepacia genomovar III in cystic fibrosis

OBJECTIVES

We sought to determine whether the same Burkholderia cepacia complex strain has persisted as the dominant clonal lineage among patients in a large cystic fibrosis (CF) treatment center during the past 2 decades.

STUDY DESIGN

The inter-city spread of B cepacia through transfer of a colonized patient and the impact of infection control measures in containing inter-patient transmission were investigated. We analyzed all available B cepacia complex isolates recovered from 1981 to 1987 and from 1996 to 2000 at one large CF treatment center (Center A) and from 1997 to 2000 at another center (Center B). Incidence of B cepacia complex infection and infection control measures in both centers were assessed.

RESULTS

Seventeen (81%) of 21 Center A patients from whom B cepacia complex bacteria were recovered between 1981 and 1987 and 40 (97%) of 41 patients culture-positive between 1996 and 2000 were infected with the same genomovar III strain. Transfer of a colonized patient from Center A to Center B was associated with an increase in B cepacia complex infection in Center B, all of which was with the Center A dominant strain. This strain, designated PHDC, lacks both B cepacia epidemic strain and cblA markers.

CONCLUSIONS

B cepacia complex strains may remain endemic in CF treatment centers for many years. Responsible bacterial and host factors and optimal infection control measures to prevent inter-patient spread remain to be identified.