Additive predictive power of the CHA2DS2-VASc and HAS-BLED scores for mortality in patients with atrial fibrillation

Background and objectives

In atrial fibrillation (AF), assessment of thromboembolic and bleeding risks are recommended to prescribe anticoagulation for stroke prevention. However, AF also increases mortality, and predictors of death are less characterized than predictors for stroke. We investigated the predictive power for mortality of the CHA2DS2-VASc, the HAS-BLED score and their combination.

Methods

Individual patient data were analyzed from the PREvention oF thromboembolic events-European Registry in Atrial Fibrillation (PREFER AF), a prospective real-world registry with a 12-month follow-up, with a total of 7243 patients enrolled from 461 hospitals and 7 European countries (Austria, France, Germany, Italy, Spain, Switzerland, and United Kingdom). Logistic regression was used to analyze the relationship of the CHA2DS2-VASc and HAS-BLED scores, and their combinations with outcome events, including mortality, at one year. The predictive ability of the scores was analyzed by comparing c-statistics.

Results

The study sample consisted of 5,209 AF patients with complete information on both scores. Mean age was 71.8±10.46 years; 3145 subjects (60.4%) were male. Events rate of stroke/SEE and major bleeding at one-year were 2.3% (122 patients) and 2.9% (149 patients), respectively. At one year, 3.1% of patients died (160 out of 5,209). Both scores had broadly similar c-statistics; for CHA2DS2-VASc: 0.637, 0.656 and 0.616 for models predicting mortality, SSE and major bleeding, respectively; for HAS-BLED: 0.620, 0.647, and 0.627, respectively. When including the individual components of both scores separately, c-statistics increased to 0.715, 0.694 and 0.636 with CHA2DS2-VASc, and to 0.681, 0.697 and 0.680 with HAS-BLED. The predictive power with both scores combined, removing overlapping components, was higher, with a c-statistic of 0.74, 0.73 and 0.70 for mortality (Table), SSE and major bleeding, respectively.

Conclusion

Both the CHA2DS2-VASc and the HAS-BLED score predict mortality similarly in AF, and a combination of the score components increases prediction significantly. Such combination may thus be clinically useful.

Funding Acknowledgement

Type of funding source: None

Collaborations in gynecologic oncology education and research in low- and middle- income countries: Current status, barriers and opportunities

Eighty-five percent of the incidents and deaths from cervical cancer occur in low and middle income countries. In many of these countries, this is the most common cancer in women. The survivals of the women with gynecologic cancers are hampered by the paucity of prevention, screening, treatment facilities and gynecologic oncology providers. Increasing efforts dedicated to improving education and research in these countries have been provided by international organizations. We describe here the existing educational and research programs that are offered by major international organizations, the barriers and opportunities provided by these collaborations and hope to improve the outcomes of cervical cancer through these efforts.

Detection and correlation of pre-operative, frozen section, and final pathology in high-risk endometrial cancer

PURPOSE

To evaluate sensitivity and specificity of pre-operative and frozen section pathologic evaluation (FSA) in predicting high-risk (HR) histology endometrial cancer.

MATERIALS AND METHODS

A retrospective analysis was performed on all patients diagnosed with endometrial cancer at a single institution. Medical records were abstracted for baseline characteristics, surgical reports for staging, and final histology was confirmed by a gynecologic pathologist.

RESULTS

868 patients were identified. Of these, 118 had Grade 3 endometrioid, 36 clear cell carcinoma (CCC), 47 carcinosarcoma (CS), and 84 uterine papillary serous carcinoma (UPSC) histology. Endometrial biopsy (EMB) had an overall sensitivity of 90%, 77% for low grade, 78% for HR, with a specificity of 0%. For dilation and curettage (D&C), overall sensitivity was 85%, 69% for low grade, and 77% for HR. Specificity was 33%. Sensitivities for combined pre-operative testing for G3 endometrioid, CCC, CS, and UPSC were: 56%, 28%, 72%, and 60%, respectively. For frozen section analysis (FSA), overall sensitivity was 77%, and 67% for low and high grade. For G3 endometrioid, CCC, CS, and UPSC, sensitivities were 57%, 20%, 74%, 32%, respectively. Specificity was 95%. FSA identified an additional six patients (8%) with UPSC, CCC or CS that were pre-operatively low risk, providing an 8% improvement in sensitivity but decreased specificity.

CONCLUSIONS

Pre-operative EMB and D&C are overall very sensitive for detecting endometrial cancer; however, sensitivity decreases with HR histology. Pre-op testing will miss 28% of HR diagnoses and FSA provides an opportunity to identify some patients with UPSC, CCC, and CS. If pre-operative results suggest HR cancer, the surgeon should proceed with comprehensive surgical staging without an FSA.

Association of genetic variation in FTO with risk of obesity and type 2 diabetes with data from 96,551 East and South Asians

AIMS/HYPOTHESIS

FTO harbours the strongest known obesity-susceptibility locus in Europeans. While there is growing evidence for a role for FTO in obesity risk in Asians, its association with type 2 diabetes, independently of BMI, remains inconsistent. To test whether there is an association of the FTO locus with obesity and type 2 diabetes, we conducted a meta-analysis of 32 populations including 96,551 East and South Asians.

METHODS

All studies published on the association between FTO-rs9939609 (or proxy [r (2) > 0.98]) and BMI, obesity or type 2 diabetes in East or South Asians were invited. Each study group analysed their data according to a standardised analysis plan. Association with type 2 diabetes was also adjusted for BMI. Random-effects meta-analyses were performed to pool all effect sizes.

RESULTS

The FTO-rs9939609 minor allele increased risk of obesity by 1.25-fold/allele (p = 9.0 × 10(-19)), overweight by 1.13-fold/allele (p = 1.0 × 10(-11)) and type 2 diabetes by 1.15-fold/allele (p = 5.5 × 10(-8)). The association with type 2 diabetes was attenuated after adjustment for BMI (OR 1.10-fold/allele, p = 6.6 × 10(-5)). The FTO-rs9939609 minor allele increased BMI by 0.26 kg/m(2) per allele (p = 2.8 × 10(-17)), WHR by 0.003/allele (p = 1.2 × 10(-6)), and body fat percentage by 0.31%/allele (p = 0.0005). Associations were similar using dominant models. While the minor allele is less common in East Asians (12-20%) than South Asians (30-33%), the effect of FTO variation on obesity-related traits and type 2 diabetes was similar in the two populations.

CONCLUSIONS/INTERPRETATION

FTO is associated with increased risk of obesity and type 2 diabetes, with effect sizes similar in East and South Asians and similar to those observed in Europeans. Furthermore, FTO is also associated with type 2 diabetes independently of BMI.

Photoluminescence properties of InAs nanowires grown on GaAs and Si substrates

We report the first photoluminescence (PL) characterization of InAs nanowires (NWs). The InAs NWs were grown on GaAs(111) B and Si(111) substrates using the Au-assisted molecular beam epitaxy (MBE) growth technique or metal-organic chemical vapor deposition (MOCVD). We compared the PL response of four samples grown under different conditions using MBE or MOCVD. High-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) patterns were utilized to determine the crystal structure and growth directions of the NWs to relate PL features to NW structural parameters. We observed mainly three PL peaks which were below, near and above InAs bandgaps, respectively. Temperature and excitation intensity dependence PL measurements were also performed to help elucidate the origins of the PL peaks of NWs. Of particular interest was a band-edge emission peak that was blue-shifted due to quantization effects of the InAs NWs, as confirmed by our calculation.

A case-controlled study of total laparoscopic radical hysterectomy with pelvic lymphadenectomy versus radical abdominal hysterectomy in a fellowship training program

To determine whether total laparoscopic radical hysterectomy (TLRH) is a feasible alternative to an abdominal radical hysterectomy (ARH) in a gynecologic oncology fellowship training program. We prospectively collected cases of all of the patients with cervical cancer treated with TLRH and pelvic lymphadenectomy by our division from 2000 to 2006. All of the patients from the TLRH group were matched 1:1 with the patients who had ARH during the same period based on stage, age, histological subtype, and nodal status. Thirty patients were treated with TLRH with a mean age of 48.3 years (range, 29–78 years). The mean pelvic lymph node count was 31 (range, 10–61) in the TLRH group versus 21.8 (range, 8–42) (P < 0.01) in the ARH group. Mean estimated blood loss was 200 cc (range, 100–600 cc) in the TLRH with no transfusions compared to 520 cc in the ARH group (P < 0.01), in which five patients required transfusions. Mean operating time was 318.5 min (range, 200–464 min) compared to 242.5 min in the ARH group (P < 0.01), and mean hospital stay was 3.8 days (range, 2–11 days) compared to 5.6 days in the ARH group (P < 0.01). All TLRH cases were completed laparoscopically. All patients in the TLRH group are disease free at the time of this report. In conclusion, it is feasible to incorporate TLRH training into the surgical curriculum of gynecologic oncology fellows without increasing perioperative morbidity. Standardization of TLRH technique and consistent guidance by experienced faculty is imperative.

Immunohistochemical characterization of cancer antigen in uterine cancers

The pattern of cancer antigen (CA-125) expression by immunohistochemistry (IHC) was investigated in malignant and nonneoplastic endometrium in endometrial carcinoma. Ninety cases of primary uterine carcinomas (65 endometrioid [EM] carcinoma, 15 serous papillary [SP] carcinoma, 6 carcinosarcomas [malignant mixed müllerian tumors], and 4 clear cell carcinoma [CC]) and adjacent atrophic and/or hyperplastic endometrium were analyzed by IHC for CA-125 expression. The percentage and intensity of luminal, apical, basal, and diffuse cytoplasmic immunostaining of epithelial cells were categorized on a scale of 0-4. The immunoreaction score (IRS score) was calculated and correlated with the grade and stage of carcinoma according to the histologic type. CA-125 expression (3-4/4) was localized in apical borders of grade 1 and grade 2 EM carcinoma and was weak or negative (0-1/4) in grade 3 EM. Mucinous differentiation in EM was associated with intense luminal and apical staining. Squamous areas and stroma showed no staining at all. SP carcinoma and endometrial intraepithelial carcinoma showed much higher mean IRS score than EM. In malignant mixed müllerian tumors (MMMT), the epithelial component stained as above according to the type of epithelial cell differentiation of the neoplastic cells. Benign proliferative glands showed moderate apical luminal, basal, and cytoplasmic staining. Intense diffuse staining was observed in atypical complex hyperplasia. Different patterns of CA-125 immunostaining were observed in normal, hyperplastic, and neoplastic endometrium. IRS score correlated with the grade but not with the stage of EM carcinoma. The intense different staining pattern of endometrium with atypical complex hyperplasia suggests that CA-125 may be a useful diagnostic aid.

Effective palliative radiation therapy in advanced and recurrent ovarian carcinoma

PURPOSE

To retrospectively review our experience using radiation therapy as a palliative treatment in ovarian carcinoma.

METHODS AND MATERIALS

Eighty patients who received radiation therapy for ovarian carcinoma between 1983 and 1998 were reviewed. The indications for radiation therapy, radiation therapy techniques, details, tolerance, and response were recorded. A complete response required complete resolution of the patient's symptoms, radiographic findings, palpable mass, or CA-125 level. A partial response required at least 50% resolution of these parameters. The actuarial survival rates from initial diagnosis and from the completion of radiation therapy were calculated.

RESULTS

The median age of the patients was 67 years (range 26 to 90 years). A median of one laparotomy was performed before irradiation. Zero to 20 cycles of a platinum-based chemotherapy regimen were delivered before irradiation (median = 6 cycles). The reasons for palliative treatment were: pain (n = 22), mass (n = 23), obstruction of ureter, rectum, esophagus, or stomach (n = 12), a positive second-look laparotomy (n = 9), ascites (n = 8), vaginal bleeding (n = 6), rectal bleeding (n = 1), lymphedema (n = 3), skin involvement (n = 1), or brain metastases with symptoms (n = 11). Some patients received treatment for more than one indication. Treatment was directed to the abdomen or pelvis in 64 patients, to the brain in 11, and to other sites in 5. The overall response rate was 73%. Twenty-eight percent of the patients experienced a complete response of their symptoms, palpable mass, and/or CA-125 level. Forty-five percent had a partial response. Only 11% suffered progressive disease during therapy that required discontinuation of the treatment. Sixteen percent had stable disease. The duration of the responses and stable disease lasted until death except in 10 patients who experienced recurrence of their symptoms between 1 and 21 months (median = 9 months). The 1-, 2-, 3-, and 5-year actuarial survival rates from diagnosis were 89%, 73%, 42%, and 33%, respectively. The survival rates calculated from the completion of radiotherapy were 39%, 27%, 13%, and 10%, respectively. Five percent of patients experienced Grade 3 diarrhea, vomiting, myelosuppression, or fatigue. Fourteen percent of patients experienced Grade 1 or 2 diarrhea, 19% experienced Grade 1 or 2 nausea and vomiting, and 11% had Grade 1 or 2 myelosuppression.

CONCLUSIONS

In this series of radiation therapy for advanced ovarian carcinoma, the response, survival, and tolerance rates compare favorably to those reported for current second- and third-line chemotherapy regimens. Cooperative groups should consider evaluating prospectively the use of radiation therapy before nonplatinum and/or nonpaclitaxel chemotherapy in these patients.

Vaginal Reconstruction With a Rectus Abdominis Musculoperitoneal Flap

In more than 300 clinical cases, the authors have observed and documented the presence of a branch of the deep inferior epigastric artery that penetrates the posterior rectus sheath near the umbilicus. Their cadaveric anatomic and animal injection studies confirm the vascularity of the peritoneum via the deep inferior epigastric artery. They report 2 patients treated with a new technique of vaginal reconstruction using a thin, pliable flap with a peritoneal-lined rectus abdominis muscle based on the deep inferior epigastric vessels.

Genetic epidemiology of type 1 diabetes mellitus in Taiwan

Some environmental and genetic factors play important roles in etiopathogenesis of type 1 or insulin-dependent diabetes mellitus (IDDM). HLA genes, the IDDM1 locus located the human chromosome 6, were found to be associated with insulin-dependent diabetes mellitus. However, the incidence of IDDM varied greatly among various populations. To evaluate the pathogenetic factors contributing to the development of IDDM in Taiwan, HLA typing was performed in a group of IDDM unrelated individuals and IDDM pedigrees along with the normal controls from the northern Taiwan. DNA genotypes of class II HLA were done by polymerase-chain-reaction based oligotyping techniques. We confirmed that class II HLA genes were significantly associated with IDDM in Taiwan. To study detailed molecular structure of class II HLA molecules and disease association, we examined several amino acid residues on DQalpha and DQbeta chains and the molecular mechanisms to explain the heterozygotic effect of the DR3/DR4 and DR3/DR9 in the Chinese population. Linkage analysis in our pedigrees confirmed the association between HLA and IDDM in population association studies. Among the several class II alleles, a closer segregation of HLA-DQB1*0401 to the affected persons might suggest that HLA-DQB1*0401 itself or an allele closely linked to the DQB1 locus was the IDDM-predisposing allele in Taiwanese. For IDDM2 (INS) region, association with IDDM was not found due to that more than 90% of the population carried class I alleles. In our collection of IDDM, we found few cases (2.4%) carried mitochondrial DNA mutation. Our studies in Taiwanese confirm a multigenetic nature for IDDM.

SpinThin, a simple, inexpensive technique for preparation of thin-layer cervical cytology from liquid-based specimens: data on 791 cases

BACKGROUND

Acceptance of liquid-based fixatives for cervical cytology has been limited by the more complex slide-preparation procedures, increased cost, and reports that increased sensitivity has been based largely on comparison with conventional cytology without histologic correlation. Here the authors describe and evaluate a technically simple and relatively inexpensive method (which they call SpinThin) for preparing Cytospin (Shandon Inc., Pittsburgh, PA) cervical cytology slides from samples in liquid fixative using a modified electric toothbrush holder to put the cells in suspension. Results are compared with conventional cytology and histologic biopsy.

METHODS

A total of 791 cervical cytology specimens from 2 patient groups at high risk of uterine cervical neoplasia were entered into this study, and a spatula and cytobrush (174 specimens) or cytobroom (617 specimens) were used to collect conventional smears. The collection device with remaining cellular sample was placed in an alcohol-based fixative solution; the cells were put into suspension by a brief burst of vibration using a modified electric toothbrush holder, then cytocentrifuged on a slide and stained with the Papanicolaou technique.

RESULTS

Specimen adequacy in SpinThin slides was better than that of conventional cytology smears. However, the prevalence of dysplasia, including atypical squamous cells of undetermined significance (ASCUS-D), in conventional smears and SpinThin slides was the same--27% and 25%, respectively--and excluding ASCUS-D, it was 20% in both. The prevalence of neoplasia (low or high grade squamous intraepithelial lesion, or carcinoma) histologically was 31% in the 647 cases biopsied, and agreement with histology was similar for SpinThin and conventional smears.

CONCLUSIONS

Using a simple and relatively inexpensive new technique (Spin-Thin), slides prepared from fluid-based cervical cytology specimens obtained with the cytobrush or cytobroom correlated very well with the corresponding conventional smears within major diagnostic categories, and both correlated well with histology.

Preliminary phase II clinical and pharmacokinetic study of 9-cis retinoic acid in advanced cervical cancer. New York Gynecologic Oncology Group

PURPOSE

9-cis retinoic acid (ALRT 1057; 9cRA) is a promising new retinoid that binds to all known retinoic acid receptors (RAR and RXR), potentially providing it with a broader spectrum of biologic activity than either 13-cis retinoic acid or all-trans retinoic acid. It has been shown to be at least as active as all-trans retinoic acid as a differentiation-inducing and antiproliferative agent in both in vivo and in vitro tumor model systems.

METHODS

The New York Gynecologic Oncology Group undertook a prospective, multi-institutional phase II clinical and pharmacokinetic trial of 9cRA in patients with advanced or recurrent squamous cell or adenosquamous cell carcinoma of the uterine cervix. Patients received daily oral doses of 140 mg/m2 of 9cRA. 9cRA and its metabolites were determined by reversed-phase HPLC in plasma samples drawn at 0.5 to 8 hours.

RESULTS

Sixteen patients with advanced or recurrent carcinoma of the cervix were enrolled. Therapy was well tolerated with no unexpected toxicities. There were no complete or partial responses observed, indicating that a response rate of 20% or greater to this agent could be ruled out with 95% confidence. Pharmacokinetic parameters for 9cRA on day 1 were in agreement with previous studies. The area under the plasma versus time curves for 9cRA declined by 69% between days 1 and 8 with daily 9cRA dosing and remained at this low level in those patients evaluated on day 28. 4-oxo-9-cis retinoic acid (4-oxo-9cRA) was identified as a major plasma metabolite of 9cRA. Plasma levels of 4-oxo-9-cRA were initially 71% of those of 9cRA, but in contrast to 9cRA, there was no decline in plasma levels on days 8 and 28. The ratio of the area under the curve for the 4-oxo metabolite relative to that of the parent compound increased from less than 1 on day 1 to approximately 2.4 on days 8 and 28. Thus, despite early induction of its own metabolism, levels of total retinoid metabolites persisted at pharmacologic levels at day 28.

CONCLUSIONS

9cRA with this dose and schedule was inactive in women with advanced carcinoma of the cervix. Despite a decline in plasma levels of 9cRA over time, levels of the 4-oxo metabolite tended to persist. While the 4-oxo metabolite is less potent than the parent compound, these data nevertheless suggest that the lack of clinical activity in this patient population may not be attributable exclusively to suboptimal pharmacokinetic parameters.

Transglutaminase-induced cross-linking between subdomain 2 of G-actin and the 636-642 lysine-rich loop of myosin subfragment 1

G-actin was covalently cross-linked with S1 in a bacterial transglutaminase-catalyzed reaction. The cross-linking sites were identified with the help of fluorescent probes and limited proteolysis as the Gln-41 on the DNase I binding loop of subdomain 2 in G-actin and a lysine-rich loop (residues 636-642) on the S1 heavy chain. The same lysine-rich loop was cross-linked to another region of G-actin in a former study (Combeau, C., D. Didry, and M-F. Carlier. 1992. J. Biol. Chem. 267:14038-14046). This indicates the existence of more than one G-actin-S1 complex. In contrast to G-actin, no cross-linking was induced between F-actin and S1 by the transglutaminase reaction. This shows that in F-actin the inner part of the DNase I binding loop, where Gln-41 is located, is not accessible for S1. The cross-linked G-actin-S1 polymerized upon addition of 2 mM MgCl2 as indicated by electron microscopy and sedimentation experiments. The filaments obtained from the polymerization of cross-linked actin and S1 were much shorter than the control actin filaments. The ATPase activity of the cross-linked S1 was not activated by actin, whereas the K+ (EDTA)-activated ATPase activity of S1 was unaffected by the cross-linking. The cross-linking between G-actin and S1 was not influenced by the exchange of the tightly bound calcium to magnesium; however, it was inhibited by the exchange of the actin-bound ATP to ADP. This finding supports the view that the structure of the DNase binding loop in ADP-G-actin is somewhere between the structures of ATP-G-actin and F-actin.

Adaptation of gamma-aminobutyric acid type A receptors to alcohol exposure: studies with stably transfected cells

We studied the adaptation of gamma-aminobutyric acid type A (GABAA) receptor function to chronic ethanol exposure in cells stably transfected with the following GABAA receptor subunits: alpha-1 beta-2 gamma-2L, alpha-1 beta-2 gamma-2S, alpha-1 beta-3 gamma-2S, alpha-1 beta-1, alpha-5 beta-3 gamma-3 and alpha-6 beta-3 gamma-2S. Chronic exposure to ethanol resulted in a decrease in muscimol-stimulated 36Cl- flux and a decrease in modulation of that flux by ethanol, flunitrazepam, methyl-6,7-4-dimethoxy-4-ethyl-beta-carboline-3-carboxylate and pregnanolone without any change in the modulation by pentobarbital or zinc. Direct activation of the GABAA receptor by pentobarbital was enhanced by chronic ethanol treatment. Reduction of the action of muscimol, ethanol and flunitrazepam differed in the duration and amount of ethanol required to see an effect. Reduction of the action of ethanol of alpha-1 beta-2 gamma-2L cells occurred within 15 min and was near-maximal for 25 mM ethanol, whereas reduction of the actions of muscimol and flunitrazepam actions required hours of exposure and higher concentrations of ethanol. Chronic ethanol exposure produced a reduction in the Emax value for the action of muscimol for all six subunit combinations, but quantification of surface receptors by immunolabeling showed no change in GABAA receptor density. The differences in alcohol sensitivity and time courses for different effects of ethanol indicate multiple mechanisms of adaptation of GABAA receptors. Use of stably transfected cells rules out "subunit substitution" as a mechanism for these changes and points to post-translational changes (e.g., phosphorylation, receptor assembly) as the most likely mechanisms. These in vitro findings are compared with results from in vivo studies.

Inflammatory infiltrates and complete absence of Purkinje cells in anti-Yo-associated paraneoplastic cerebellar degeneration

We studied the nervous systems and tumors of two patients with anti-Yo-associated paraneoplastic cerebellar degeneration (PCD). In both patients the underlying tumor was an ovarian adenocarcinoma that expressed Yo antigens and contained extensive infiltrates of lymphocytes and plasma cells. The major central nervous system findings were a complete loss of cerebellar Purkinje cells with Bergmann astrogliosis. One patient had inflammatory infiltrates in the medulla and pons, and moderate axonal loss and demyelination involving the spinal cord. No inflammatory infiltrates were identified in the cerebrum, cerebellum or brain-stem of the other patient. Using quantitative Western blot analysis, deposits of anti-Yo IgG could not be demonstrated in the nervous system, possibly as a result of the loss of cells expressing Yo antigens. The detection of the anti-Yo antibody as a common marker of PCD in one patient with inflammatory infiltrates and another without infiltrates suggests that some PCD pathologically classified as "non-inflammatory" may represent a final burn-out stage of a cellular immune-mediated disorder. Our findings indicate that Purkinje cells are the main, but not necessarily the exclusive, targets of this disorder.

Differential regulation of EGF production, EGF receptor-binding, and cellular growth by sodium-butyrate in hep3b and plc/prf/5 human hepatoma-cells

Hep3B and PLC/PRF/5 human hepatoma cells express epidermal growth factor (ECF) mRNA and secret this polypeptide growth factor into the culture medium. The production of EGF was inhibited by sodium butyrate in a dose-dependent manner. EGF receptor numbers in both cell lines were increased after treatment with butyrate for 2 days, In addition, the binding affinity of EGF to its receptor was decreased in butyrate-treated PLC/PRF/5 cells while it did not change in Hep3B cells. EGF-stimulated cell growth in PLC/PRF/5 cells was attenuated by sodium butyrate whereas no significant inhibition df cell growth of Hep3B cells was found in the same condition. Our results suggest that EGF acts as an autocrine growth stimulator in human hepatoma cells and sodium butyrate can differentially regulate the responses of hepatoma cells to EGF by modulating the differentiation states of these cells.

Effects of zinc-desferrioxamine on Plasmodium falciparum in culture

The zinc-desferrioxamine (Zn-DFO) complex is considered to be more permeative into parasitized erythrocytes than is the metal-free DFO. The former may penetrate the cell and exchange its bound zinc for ferric ions, rendering the iron unavailable for vital parasite functions. The effects of these compounds on the in vitro development of Plasmodium falciparum are compared. The results indicate that Zn-DFO is superior to DFO, especially at concentrations below 20 microM, as shown by decreased levels of hypoxanthine incorporation, lower levels of parasitemia, and interference with the life cycle of the parasite. At low concentrations, DFO even enhanced parasite growth. Such an enhancement was not observed following exposure to Zn-DFO. Experiments in which the compounds were removed from the cultures indicated that parasites treated with Zn-DFO are less likely to recover at a later stage. Since DFO has already been used in humans for the treatment of malaria, its complex with zinc, which is more effective in vitro, should also be examined in vivo.