Abstract P5-11-16: Do patients and nurses outside clinical trial prefer subcutaneous trastuzumab over conventional intravenous infusion? Instituto Oncologico Nacional experience

Background In the PrefHer study, subcutaneous administration of trastuzumab was preferred over intravenous administration (iv). In 2014 our hospital approved subcutaneous (sc) trastuzumab for use in patients with early or metastatic Her 2 positive breast cancer. The aim of this study was to evaluate patients (pts) and nurses´s preferences in our institution.

Methods Patients with Her2 postive breast cancer and nurses who had received or administered both sc and iv trastuzumab were interviewed to evaluate their preference. Preference for sc was compared with a linear chi squared test.

Results 55 pts were interviewed. Median age was 53 years (30-83). 30 patients in adjuvant/neoad setting and 25 pts in the palliative setting. 41 pts (74.5%) preferred sc 95% CI (63-86) , 3 pts (5.5%) preferred iv 95% CI (-0.5-11.5) and 11 pts (20%) did not have preference 95% CI (9.4-20%) p< 0.0001. 72% of pts considered that sc trastuzumab was more convenient (p<0.0001). 11 nurses experienced with both iv and sc trastuzumab administration answered the questionnaire. Median age 41 years (30-55). 10/11 nurses preferred sc administration, 1/10 indicated no preference. All nurses considered that sc was the most convenient administration method for the patients and is highly recommended. The main reason for patients and nurses preference was that sc administration saved time.

Conclusion Patients and nurses prefer s.c over iv trastuzumab. Our results are consistent with PrefHer study. Incorporation of sc trastuzumab could improve quality of care in patients with Breast Cancer Her 2 positive.

Citation Format: Castillo-Fernandez O, Cabreja A, Arauz E, Bellido D, Lim M, Lopez R, Montano L. Do patients and nurses outside clinical trial prefer subcutaneous trastuzumab over conventional intravenous infusion? Instituto Oncologico Nacional experience [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-11-16.

VP8* antigen produced in tobacco transplastomic plants confers protection against bovine rotavirus infection in a suckling mouse model

Group A rotavirus is a major leading cause of diarrhea in mammalian species worldwide. In Argentina, bovine rotavirus (BRV) is the main cause of neonatal diarrhea in calves. VP4, one of the outermost capsid proteins, is involved in various virus functions. Rotavirus infectivity requires proteolytic cleavage of VP4, giving an N-terminal non-glycosilated sialic acid-recognizing domain (VP8*), and a C-terminal fragment (VP5*) that remains associated with the virion. VP8* subunit is the major determinant of the viral infectivity and one of the neutralizing antigens. In this work, the C486 BRV VP8* protein was produced in tobacco chloroplasts. Transplastomic plants were obtained and characterized by Southern blot, northern blot and western blot. VP8* was highly stable in the transplastomic leaves, and formed insoluble aggregates that were partially solubilized by sonication. The recombinant protein yield was 600 μg/g of fresh tissue (FT). Both the soluble and insoluble fractions of the VP8* plant extracts were able to induce a strong immune response in female mice as measured by ELISA and virus neutralization test. Most important, suckling mice born to immunized dams were protected against oral challenge with virulent rotavirus. Results presented here contribute to demonstrate the feasibility of using antigens expressed in transplastomic plants for the development of subunit vaccines.

Standardisation of the waist circumference (WC) for each range of body mass index (BMI) in adult outpatients attended to in Endocrinology and Nutrition departments

By this study we seek the expectable range of waist circumference (WC) for every degree of body mass index (BMI), which will serve to studies targeting ascertaining the health risk. We studied 2,932 patients (39.6% men and 60.4% women, between 18 and 96 years ) of the same ethnic group who consecutively attended outpatient departments of our clinics between 2000 and 2004. BMI correlated linearly with the WC (cc: 0.85; p < 0.001). The men, the obese, and diabetics were older (p < 0.001). BMI was greater in women and WC in men. The women had a greater WC if they had diabetes (p < 0.01), being equal to diabetic males. The men had greater WC when they had diabetes (p < 0.001). Waist at risk was detected (men > or = 102 cm and women > or = 88 cm) in 94.3% of the obese, in 32.3% of overweight patients, in 3.8% of patients with BMI < 25, in 84.3% of diabetics, and in 72.6% of patients without diabetes. We made graphic standardisation of WC with regard to BMI, and we calculated the percentiles 10, 25, 50, 75 and 90, grouping in ranges of 2 kg/m(2) of BMI. The diabetic patients are grouped in ranges of 4 kg/m(2). As conclusion we present a standardisation of the WC measurement of patients attended to in our Endocrinology and Nutrition practices distributed in percentiles as a clinically usable tool to define the ranges of WC for every BMI value.

Cardiovascular risk factor management is poorer in diabetic patients with undiagnosed peripheral arterial disease than in those with known coronary heart disease or cerebrovascular disease. Results of a nationwide study in tertiary diabetes centres

AIMS

To assess whether patients with Type 2 diabetes mellitus and unrecognized peripheral arterial disease (PAD), detected by the ankle-brachial index (ABI), have poorer cardiovascular risk factor management (CVRFs) and receive fewer medications than patients previously diagnosed with coronary heart disease (CHD) or cerebrovascular disease (CVD).

METHODS

In 31 diabetes centres throughout Spain, 1303 patients with Type 2 diabetes mellitus were screened for PAD using the ABI. Patient history of CHD and CVD and treatment and control of CVRFs were recorded.

RESULTS

Forty-one patients had an ABI > 1.30 and were excluded, leaving 1262 patients (age 65.3 +/- 7.7 years) for the study. Of those screened, 790 patients had a normal ABI (ABI > 0.9) and no known history of CHD or CVD (no CHD/CVD/PAD group), 194 had unrecognized PAD (ABI < or = 0.9) with no known history of CHD or CVD (undiagnosed PAD group) and 278 had a known history of CHD and/or CVD (CHD/CVD group). The undiagnosed PAD group had higher low-density lipoprotein (LDL) cholesterol (2.9 +/- 0.83 vs. 2.4 +/- 0.84 mmol/l; P < 0.001) and systolic blood pressure (150 +/- 20 vs. 145 +/- 21 mmHg; P < 0.001) compared with the CHD/CVD group. They were less likely to take statins (56.9 vs. 71.6%; P < 0.001), anti-hypertensive agents (75.9 vs. 90.1%, P = 0.001), and anti-platelet agents (aspirin, 28.7 vs. 57.2%; P < 0.001; clopidogrel, 5.6 vs. 20.9%; P < 0.001) and more likely to smoke (21.0 vs. 9.2%; P < 0.001). Higher LDL in the undiagnosed PAD group was associated with the underutilization of statins.

CONCLUSIONS

Measurement of ABI detected a significant number of patients with PAD, who did not have CHD or CVD, but whose CVRFs were under treated and poorly controlled compared with subjects with CHD and/or CVD.

LC-MSMS identification of Arabidopsis thaliana heat-stable seed proteins: enriching for LEA-type proteins by acid treatment

Protein identification in systems containing very highly abundant proteins is not always efficient and usually requires previous enrichment or fractionation steps in order to uncover minor proteins. In plant seeds, identification of late embryogenesis abundant (LEA) proteins is often masked by the presence of the large family of storage proteins. LEA-proteins are predicted to play a role in plant stress tolerance. They are highly hydrophilic proteins, generally heat-stable, and correlate with dehydration in seeds or vegetative tissues. In the present work, we analyze the protein composition of heat-stable Arabidopsis thaliana seed extracts after treatment with trichloroacetic acid (TCA). The composition of the proteins that precipitate and those that remain in solution in 3% TCA was analyzed by two different approaches: 1D SDS-PAGE coupled to LC-ESI-MSMS analysis and a gel-free protocol associated with LC-MALDI-MSMS. Our results indicate that treating total heat-soluble extracts with 3% TCA is an effective procedure to remove storage proteins by selective precipitation and this fractionation step provides a soluble fraction highly enriched in Lea-type proteins. The analysis and determination of protein identities in this acid-soluble fraction by MS technology is a suitable system for large-scale identification of Lea-proteins present in seeds.

Recommendations from SPNS/GEAM/SENBA/SENPE/AEDN/SEDCA/GESIDA on nutrition in the HIV-infected patient

OBJECTIVE

to make recommendations on the approach to nutritional problems (malnutrition, cachexia, micronutrient deficiency, obesity, lipodystrophy) affecting HIV-infected patients.

METHODS

these recommendations have been agreed upon by a group of expertes in the nutrition and care of HIV-infected patients, on behalf of the different groups involved in drafting them. Therefore, the latest advances in pathophysiology, epidemiology, and clinical care presented in studies published in medical journals or at scientific meetings were evaluated.

RESULTS

there is no single method of evaluating nutrition, and diferent techniques--CT, MRI, and DXA--must be combined. The energy requirements of symptomatic patients increase by 20-30%. There is no evidence to support the increase in protein or fat intake. Micronutrient supplementation in only necessary in special circumstances (vitamin A in children and pregnant woman). Aerobic and resistance excercise is beneficial both for cardiovascular health and for improving lean mass and muscular strength. It is important to follow the rules of food safety at every stage in the chain. Therapeutic intervention in anorexia and cachexia must be tailored, by combining nutritional and pharmacological support (appetite stimulants, anabolic steroids, and, in some cases, testosterone). Artificial nutrition (oral supplementation, enteral or parenteral nutrition) is safe and efficacious, and improves nutritional status and response to therapy. In children, nutritional recommendations must be made early, and are a necessary component of therapy.

CONCLUSION

appropriate nutritional evaluation and relevant therapeutic action are an essential part of the care of HIV-infected patients.

[The scientific basis for healthy eating]

A diet is healthy when it encourages good health and reduces the risk of diet-related chronic diseases. Epidemiological research has demonstrated a close relationship between diet and the risk of developing these chronic diseases, which are characterized by high morbidity and mortality. The Mediterranean diet is a tradition that goes back for centuries and which contributes to excellent nutritional status; this diet is highly palatable and forms part of world culture. Some of the most outstanding recent studies on the relationship between unhealthy lifestyle and the risk of disease are reviewed.

Reactivation of hepatitis B in an HIV-infected patient with antibodies against hepatitis B core antigen as the only serological marker

Presented here is the first report of clinical reactivation of hepatitis B virus (HBV) in an HIV-infected patient who previously had anti-HBc as the only serological marker of past infection (anti-HBc alone). Reactivation occurred after lamivudine was removed from the patient's antiretroviral treatment regimen due to lack of virological response. HIV-infected patients frequently present anti-HBc alone, and in some cases this serological profile is associated with occult HBV infection. The current case demonstrates the importance of ruling out the possibility of occult infection in this patient group.

[Acute renal failure and hypertension]

Ischemic nephropathy could be complicated with hypertension and acute worsening of chronic renal failure secondary to ACE inhibitors or AT receptor antagonist treatments and arterial occlusion. We describe a patient with bilateral renal artery stenosis and hypertension treated with ATI receptor antagonist (valsartan) that developed rapid worsening of renal function that required dialysis. Percutaneous transluminal renal artery angioplasty and stenting, complemented with hydratation and valsartan suppression achieves rapid and sustained recovery of renal function.

Alternation of generations in Andricus corruptrix (Schlechtendal): comments on and description of a new sexual form (Hymenoptera: Cynipidae)

Life cycle of A. corruptrix (Schlechtendal, 1870) is treated and corrections to previous experiments are discussed. A new sexual form for A. corruptrix is herein described, while A corruptrix forma larshemi is considered a valid species and for taxonomical reasons is renamed as Andricus improprius n. stat & n.sp, only known by the sexual form, and not linked with A. corruptrix. Lectotypes for A. improprius n. stat & n, sp. (= A. larshemi not available) are also designated.

Lipid rafts are required for GLUT4 internalization in adipose cells

It has been recently reported that insulin recruits a novel signaling machinery to lipid rafts required for insulin-stimulated GLUT4 translocation [Baumann, A., Ribon, V., Kanzaki, M., Thurmond, D. C., Mora, S., Shigematsu, S., Bickel, P. E., Pessin, J. E. & Saltiel, A. R. (2001) Nature 407, 202-207, 2000; Chiang, S. H., Baumann, C. A., Kanzaki, M., Thurmond, D. C., Watson, R. T., Neudauer, C. L., Macara, I. G., Pessin, J. E. & Saltiel, A. R. (2001) Nature 410, 944-948]. We have assessed the role of lipid rafts on GLUT4 traffic in adipose cells. High GLUT4 levels were detected in caveolae from adipocytes by two approaches, the mechanical isolation of purified caveolae from plasma membrane lawns and the immunogold analysis of plasma membrane lawns followed by freeze-drying. The role of lipid rafts in GLUT4 trafficking was studied by adding nystatin or filipin at concentrations that specifically disrupt caveolae morphology and inhibit caveolae function without altering clathrin-mediated endocytosis. These caveolae inhibitors did not affect the insulin-stimulated glucose transport. However, they blocked both the GLUT4 internalization and the down-regulation of glucose transport triggered by insulin removal in 3T3-L1 adipocytes. Our data indicate that lipid rafts are crucial for GLUT4 internalization after insulin removal. Given that high levels of GLUT4 were detected in caveolae from insulin-treated adipose cells, this transporter may be internalized from caveolae or caveolae may operate as an obligatory transition station before internalization.

Intracellular distribution of hepatic glucokinase and glucokinase regulatory protein during the fasted to refed transition in rats

We have studied the intracellular distribution in vivo of glucokinase (GK) and glucokinase regulatory protein (GKRP) in livers of fasted and refed rats, using specific antibodies against both proteins and laser confocal fluorescence microscopy. GK was found predominantly in the nucleus of hepatocytes from starved rats. GK was translocated to the cytoplasm in livers of 1- and 2-h refed animals, but returned to the nucleus after 4 h. GKRP concentrated in the hepatocyte nuclei and its distribution did not change upon refeeding. These results show that, in physiological conditions, GKRP is present predominantly in the nuclei of hepatocytes and that the translocation of hepatic GK from and to the nucleus is operative in vivo.

Lipoprotein(a) and other lipoproteins in hypothyroid patients before and after thyroid replacement therapy

AIMS

To analyse the influence of thyroid hormones on serum lipoprotein(a) (Lp(a)) concentration and other lipid parameters, and hence potentially on coronary artery disease (CAD) risk.

METHODS

Thirty-six patients with hypothyroidism and 165 age-matched control euthyroid subjects were evaluated in a cross- sectional study, determining thyroid function tests and fasting serum lipids and lipoproteins. In a follow-up study for those hypothyroid patients the same determinations were repeated after normalization of thyroid state by levothyroxine (L-T(4)) replacement therapy. Patients needing other treatments were excluded. At baseline, patients with hypothyroidism had significantly higher levels of Lp(a), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), apolipoprotein (apo) A-I and apo B, and a higher TC/high-density lipoprotein cholesterol (HDL-C) ratio than control subjects.

RESULTS

Severity of the hypothyroid state, expressed by serum thyroid-stimulating hormone, was correlated with serum levels of Lp(a), LDL-C, and TC (r= 0.64, 0.52, 0.49, P= 0.005, P= 0.033, P= 0. 048, respectively). The pretreatment Lp(a) levels were also correlated with those of posttreatment Lp(a)(r= 0.68, P= 0.002). All patients, who presented basal Lp(a) levels higher than 30 mg/dl, showed a decrease in Lp(a) concentrations by L-T(4)therapy, and these normalized in eight cases (22.2%). Euthyroid state gave rise to a significant reduction of serum Lp(a) by 32.3%, of LDL-C by 22. 8%, of TC by 17%, of apo A-I by 9.6%, and of apo B by 9.3%. After L-T(4)therapy, CAD risk, expressed as TC/HDL-C ratio, decreased by 19.9%.

CONCLUSIONS

These results show that hypothyroidism is associated not only with elevated serum levels of LDL-C but also with elevated serum Lp(a) concentrations. Lp(a) levels may be at least partially modulated by thyroid hormone-dependent mechanisms, thus increasing the risk of developing premature atherosclerosis in hypothyroid state, that might be reduced by L-T(4)therapy.

Glucose induces the translocation of glycogen synthase to the cell cortex in rat hepatocytes

After incubation with glucose a dramatic change in the intracellular distribution of glycogen synthase was observed in rat hepatocytes. Confocal laser scanning microscopy showed that glycogen synthase existed diffusely in the cytosol of control cells, whereas in cells incubated with glucose it accumulated at the cell periphery. Colocalization analysis between glycogen synthase immunostaining and actin filaments showed that the change in glycogen synthase distribution induced by glucose correlated with a marked increase in the co-distribution of the two proteins, indicating that, in response to glucose, glycogen synthase moves to the actin-rich area close to the membrane. When glycogen synthase was immunostained with rabbit anti-(glycogen synthase) and Protein A-colloidal gold, few particles were observed close to the membrane in control cells. In contrast, in cells incubated with glucose most of the gold particles were found near the membrane, confirming that glycogen synthase had moved to the cell cortex. Furthermore, in agreement with the glycogen synthase distribution, glycogen deposition appeared to be more active at the periphery of the cell.

Translocation and aggregation of hepatic glycogen synthase during the fasted-to-refed transition in rats

Changes in the activation state and intracellular distribution of liver glycogen synthase have been studied during the fasted-to-refed transition in rats. Glycogen synthase activity and activation state were measured in supernatants and pellets obtained after centrifugation of liver homogenates at 9200 g. Upon refeeding, the glycogen synthase activity ratio increased, in a time-dependent manner, in both fractions. The total activity of the enzyme decreased in supernatants and was quantitatively recovered in the pellets. Therefore, refeeding induced both the activation of glycogen synthase and its translocation from the soluble to the pelletable fraction. Immunocytochemical evidence indicates that refeeding induced the formation of clusters of glycogen synthase, which were recovered in the 9200 g sediments. However, the enzyme clusters did not locate with the glycogen particles in the pelletable fraction. The glycogen synthase activation state responded almost as an of-off switch to changes in the intracellular glucose 6-phosphate concentration in the range 0.2-0.3 mM. The amount of enzyme present in the pellets correlated linearly with the intracellular glucose 6-phosphate levels. These results indicate that glucose 6-phosphate is the key signal for both the activation and changes in intracellular localization of hepatic glycogen synthase in vivo.

The expression of mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme-A synthase in neonatal rat intestine and liver is under transcriptional control

Mitochondrial 3-hydroxy-3-methylglutaryl-CoA (HOMeGlt-CoA) synthase regulates ketogenesis in the liver of adult rat and in the intestine and liver of neonatal animals but whose mechanisms of regulation have not been fully defined. To investigate transcriptional control of this gene in intestine and liver of suckling rats a quantitative PCR amplification of the pre-mRNA (heteronuclear RNA), compose of part of the first exon and of the first intron, was carried out. Results show that the intestinal pre-mRNA for mitochondrial HOMeGlt-CoA synthase from suckling rats follows a pattern that is nearly identical to that of mature mRNA, with maximum levels on the ninth postnatal day then decreasing smoothly so that at weaning there is no transcriptional activity. Mitochondrial HOMeGlt-CoA synthase protein follows a pattern that is identical to the pre-mRNA and mature mRNA, suggesting no translational regulation. The changes in transcriptional activity are not produced by the presence of an alternative promoter, since the transcription-initiation site is identical in several tissues assayed, including intestine and liver. Enterocytes are the only intestinal cells that express this ketogenic enzyme, as deduced from immunolocalization experiments. The mature intestinal protein is located in mitochondria and not in the cytosol, which coincides with what is found in liver. By using analogous techniques we conclude that hepatic pre-mRNA of mitochondrial HOMeGlt-CoA synthase from suckling rats follows a pattern of expression identical to that of mature hepatic mRNA, which also suggests a transcriptional modulation of this gene in the liver of neonatal rats.

Lipoprotein lipase-mediated uptake of lipoprotein in human fibroblasts: evidence for an LDL receptor-independent internalization pathway

Lipoprotein lipase (LPL), a key enzyme in lipoprotein triglyceride metabolism, produces a marked increase in the retention and uptake of all classes of lipoproteins by cultured cells. It was previously shown that two different receptors are involved in mediating the LPL effects: heparan sulfate proteoglycans (HSPG) and the low density lipoprotein (LDL) receptor-related protein/alpha 2 macroglobulin receptor (LRP). By immunofluorescence we show here that cell surface-bound LPL displays a pattern that corresponds to the previously described distribution of cell surface HSPG. No evident relation to the distribution of bound activated alpha 2-macroglobulin (alpha 2M*) or to LRP was observed. By immunoelectron microscopy we found that after 30 min at 37 degrees C most of the detected alpha 2M* (70% of the total gold particles) was inside the cells and associated with endosomal vesicles. However, at the same time, 76% of the LPL remained at the cell surface, suggesting that, LPL is internalized by a slow endocytic process. Binding of triglyceride-rich lipoproteins (TRL) or LDL together with LPL led to a spectacular increase in bound lipoproteins, which completely colocalized with LPL. After incubation at 37 degrees C, LPL and 1,1'-dioctadecyl-3,3,3,'3'-tetramethylindocarbocyanine (DiI)-TRL formed large clusters on the cell surface. Immunofluorescene and quantitative immunoelectron microscopy provided evidence of co-internalization of LPL and apoE-containing TRL by a slow endocytic process. In the absence of LPL, the fibroblasts rapidly internalized DiI-LDL and showed fluorescence in central, lysosome-like vesicles. In contrast, when LPL was present, internalization of DiI-LDL involved small, widely distributed vesicles. This pattern slowly changed to one consisting of large perinuclear vesicles. LDL receptor-deficient fibroblasts internalized DiI-LDL, either with or without LPL, into small widely distributed vesicles and no central vesicles were seen. Chloroquine-treated normal fibroblasts internalized DiI-LDL in a pattern similar to that of receptor-deficient fibroblasts. Taken together our results suggest an alternative receptor-independent endocytosis pathway for LDL. This pathway is potentiated by LPL and is characterized by a slow uptake involving small vesicles that gradually reach lysosomes. We suggest that, through its interaction with HSPG, LPL provides high capacity binding sites for lipoproteins and a independent internalization pathway.

[The surgical opportunity in metastatic lesions of renal-cell carcinoma after a response to adjuvant immunotherapy]

Surgical resection of primary lesions and single metastasis can be curative, but surgery, used as the only therapeutic option, is not unanimously accepted in patients with multiple metastasis and, apart from other considerations, there are no established clinical criteria to allow us to predict which patients will benefit from a metastectomy. This study evaluates four patients with advanced RCC. Three had multiple pulmonary metastasis at the time of diagnosis and one presented retroperitoneal mass at 36 months of follow-up. All patients were nephrectomized and received adjuvant immunotherapy with an association of IL-2 and 2b alpha-IFN subcutaneously, obtaining partial response of the disease after two treatment courses. Later, the patients underwent debulking surgery. Two patients are still alive and have no evidence of disease progression at 28 months and 8 months of follow-up. This data and that contrasted with other authors, suggests that surgical management would be a reasonable option in patients who have partially responded to immunotherapy, even though the selection of both candidates and surgical strategy should be considered on an individual basis.

Digoxigenin-labeled phosphorothioate oligonucleotides: a new tool for the study of cellular uptake

The mechanisms and intracellular pathways by which many oligonucleotide analogs enter cells to exert the desired antisense effects are not fully understood and remain a matter of debate. In this study, we describe the synthesis of 5'-digoxigenin-labeled phosphorothioate oligonucleotides and show their use to examine intracellular oligonucleotide distribution within Epstein-Barr virus-transformed B cells. Comparison of digoxigenin-labeled and fluorescein-labeled oligonucleotide distribution shows the same intracellular fate, suggesting that digoxigenin modification does not interfere with intracellular routing. Double immunofluorescence studied by conventional fluorescence and confocal microscopy with antibodies to the labeling molecule and to lysosome-associated membrane protein indicate that oligonucleotides mainly accumulate in the lysosomal compartment. Digoxigenin labeling offers an alternative to study oligonucleotide uptake and distribution by immunoelectron microscopy. Two different approaches have been studied: immunogold labeling in heavily fixed and resin-embedded cells and immunogold labeling in lightly fixed and cryoultramicrotomy processed cells. The results confirm the major lysosomal accumulation of digoxigenin-labeled oligonucleotides and demonstrate that the antigenic capacity of digoxigenin is not damaged by any of the procedures used. Therefore, the conjugation of the functionalized digoxigenin molecule at the 5' end of phosphorothioate oligonucleotides provides a new tool in the study of oligonucleotide uptake and intracellular distribution at both cellular and ultrastructural levels.

Actin cytoskeleton of fibroblasts organizes surface proteoglycans that bind basic fibroblast growth factor and lipoprotein lipase

Cell surface proteoglycans participate in molecular events that regulate cell adhesion, migration, and proliferation. To investigate the organization of these molecules at the cell surface, the distribution of two well-known proteoglycan ligands has been studied. These ligands, lipoprotein lipase and basic fibroblast growth factor, showed a characteristic binding pattern consisting of highly organized parallel arrays that crossed the upper surface of human skin fibroblasts. The proteoglycan nature of the binding sites was evident from their susceptibility to heparinases, and from ligand displacement by heparin. Parallel localization of the ligands and actin, and treatment of the cells with cytochalasin, showed that the binding proteoglycans are organized by the actin cytoskeleton. The ligands induced a different behaviour of the binding sites on incubation of the cells at 37 degrees C. Lipoprotein lipase produced a movement of the binding proteoglycans along the actin filaments towards the cell center. In contrast, after binding of basic fibroblast growth factor the binding proteoglycans remained spread over the cell surface and actin depolymerization was induced. Since an increasing number of ligands appear to depend on proteoglycans for their interactions with their high affinity receptors, distribution and movement of proteoglycans at the cell surface that is organized by the actin cytoskeleton could direct and enhance the encounters between the ligands and their specific receptors.

Role of glucose 6-phosphate in the translocation of glycogen synthase in rat hepatocytes

Incubation of rat hepatocytes with glucose induces the translocation of glycogen synthase from soluble fractions to fractions which sediment at 10,000 g. Incubation of the cells with fructose, galactose, 2-deoxyglucose or 5-thioglucose, which activate glycogen synthase, also resulted in the translocation of the enzyme, whereas 3-O-methylglucose, 6-deoxyglucose and 1,5-anhydroglucitol, which do not cause the activation of the enzyme, were ineffective. Adenosine and carbonyl cyanide m-chlorophenylhydrazone, although activating glycogen synthase, did not induce its translocation. Mannoheptulose, which inhibits glucose phosphorylation, impaired the translocation of glycogen synthase induced by glucose. Furthermore, the extent of the translocation of the enzyme triggered by glucose and other sugars showed a high positive correlation with the intracellular concentration of glucose 6-phosphate. Microcystin, which blocks the activation of glycogen synthase by glucose, but not the accumulation of glucose 6-phosphate, did not affect the translocation of the enzyme. These results indicate that glucose 6-phosphate plays a role in the translocation of glycogen synthase in rat hepatocytes.

Fine needle aspiration biopsy in the diagnosis of thyroid cancer and thyroid disease

Fine needle aspiration biopsy (FNAB) performed for diffuse and nodular goiter in the past 5 years, was evaluated in 1399 cases. Surgery was performed on the basis of FNAB cytologic diagnosis that was positive or suggestive of malignancy and/or a suggestive clinical history. Surgery also was performed in cases of cold nodules with negative FNAB results that did not respond to 6 months of suppressive thyroxine therapy. A correlation of cytologic findings with histologic findings was possible in 415 patients who underwent surgery: the evaluation of FNAB results yielded better results when suspicious cytologic findings were considered to be positive (2.4% false-negative, 86.3% sensitivity) rather than negative (6.5% and 65.7%, respectively). FNAB has become a useful procedure in the study and diagnosis of thyroid diseases. It is a simple, rapid diagnostic procedure that may be used to expedite the management of malignant lesions.