High percentage of fat intakes, not low fat oxidation, may induce overweight cyclists

AIM

There is a number of people who recreationally or professionally participate in regular physical activity that may contribute to reduce body fat and prevent weight gain. However, there are considerable numbers of the people who have excess body fat in this population. Therefore, this study tested the hypothesis that overweight cyclists may be affected by high level of fat oxidation and/or dietary fat intake.

METHODS

Fourteen male cyclists aged 35-50 years participated in this study. All participants were defined as semi-professional cyclists and assigned to either normal cyclist group (NC, N.=7) or overwieht cyclist group (OC, N.=7) based on %body fat (OC>23%>NC). The participants underwent a maximal effort ergometer test and dietary analysis. Independent t-test and two-way ANOVA with repeated measures were used to analyze data.

RESULTS

There were no differences between NC and OC for age, height, weight, body mass index, and all cardiopulmonary fitness variables at rest and during maximal effort ergometer test. However, this study found that total fat, especially saturated fat intake of OC was significantly higher compared to one of NC (total fat: 110.88±12.98 vs. 53.56±6.94, saturated fat: 36.92±5.98 vs. 16.65±3.41, P<0.05).

CONCLUSION

The higher amount total fat intake, especially saturated fat intake not total calorie intake, may play a major role in body composition in endurance trained population.

Analysis of Antarctic proteobacteria by PCR fingerprinting and screening for antimicrobial secondary metabolites

Fifty-seven proteobacterium species were successfully isolated from soils of Barrientos Island of the Antarctic using 11 different isolation media. Analysis of 16S rDNA sequencing of these isolates showed that they belonged to eight different genera, namely Bradyrhizobium, Sphingomonas, Methylobacterium, Caulobacter, Paracoccus, Ralstonia, Rhizobium, and Staphylococcus. All isolates were studied for capability of producing antimicrobial and antifungal secondary metabolites using high-throughput screening models. Approximately 23 (13/57) and 2% (1/57) of isolates inhibited growth of Candida albicans ATCC 10231(T) and Staphylococcus aureus ATCC 51650(T), respectively. These results indicated that proteobacterium species isolates from Antarctic could serve as potential source of useful bioactive metabolites. Enterobacterial repetitive intergenic consensus (ERIC)-PCR fingerprinting produced nine clusters and 13 single isolates, with a high D value of 0.9248. RAPD fingerprinting produced six clusters and 13 single isolates, with a relatively low D value of 0.7776. ERIC-PCR analysis proved to have better discrimination capability than RAPD analysis and generated better clustering for all proteobacterium species isolates. We conclude that ERIC-PCR is a robust, reliable and rapid molecular typing method for discriminating different genera of proteobacteria.

Loss of balance between T helper type 17 and regulatory T cells in chronic human immunodeficiency virus infection

The aim of this study is to characterize the changes of CD4(+) CD25(high) forkhead box P3 (FoxP3(+) ) regulatory T cells (T(reg) ), interleukin (IL)-17 secreting T helper type 17 (Th17) cell frequencies and the balance of these two subsets in a cohort of chronic human immunodeficiency virus type 1 (HIV-1)-infected patients in China. A total of 115 untreated chronic HIV-infected individuals and 32 healthy donors were recruited in this study. Peripheral blood mononuclear cells were isolated from ethylenediamine tetracetic acid (EDTA) anti-coagulated fresh whole blood and stained to characterize the frequencies of T(reg) and Th17. Of a total 115 patients, 42 individuals including 10 elite controllers were followed-up for more than 1 year, and changes of T(reg) and Th17 frequencies were analysed over time. The continuous loss of Th17 cells was accompanied by a concomitant rise in the frequency of T(reg) cells, resulting in a loss of Th17/T(reg) balance during the progressive HIV infection. Meanwhile, the T(reg) levels, Th17 levels and Th17/T(reg) ratios of the elite controller group were comparable to those of the HIV-1 negative controls in the follow-up study. Additionally, we demonstrated that loss of balance between Th17 and T(reg) is associated with an earlier CD4 T cell decline during the course of HIV infection. Our results indicate that a loss of immune-balance of Th17 to T(reg) during HIV-1 disease progression and the persistence of such an immune-balance in the elite controllers may have a critical role in HIV-1 infection and further shed new light into understanding the pathogenesis of HIV-1.

Structural determinants in the second intracellular loop of the human cannabinoid CB1 receptor mediate selective coupling to G(s) and G(i)

BACKGROUND AND PURPOSE

The cannabinoid CB(1) receptor is primarily thought to be functionally coupled to the G(i) form of G proteins, through which it negatively regulates cAMP accumulation. Here, we investigated the dual coupling properties of CB(1) receptors and characterized the structural determinants that mediate selective coupling to G(s) and G(i).

EXPERIMENTAL APPROACH

A cAMP-response element reporter gene system was employed to quantitatively analyze cAMP change. CB(1)/CB(2) receptor chimeras and site-directed mutagenesis combined with functional assays and computer modelling were used to determine the structural determinants mediating selective coupling to G(s) and G(i).

KEY RESULTS

CB(1) receptors could couple to both G(s)-mediated cAMP accumulation and G(i)-induced activation of ERK1/2 and Ca(2+) mobilization, whereas CB(2) receptors selectively coupled to G(i) and inhibited cAMP production. Using CB(1)/CB(2) chimeric receptors, the second intracellular loop (ICL2) of the CB(1) receptor was identified as primarily responsible for mediating G(s) and G(i) coupling specificity. Furthermore, mutation of Leu-222 in ICL2 to either Ala or Pro switched G protein coupling from G(s) to G(i), while to Ile or Val led to balanced coupling of the mutant receptor with G(s) and G(i) .

CONCLUSIONS AND IMPLICATIONS

The ICL2 of CB(1) receptors and in particular Leu-222, which resides within a highly conserved DRY(X)(5) PL motif, played a critical role in G(s) and G(i) protein coupling and specificity. Our studies provide new insight into the mechanisms governing the coupling of CB(1) receptors to G proteins and cannabinoid-induced tolerance.

Conjugated Poly-P-Phenylene (PPP) From Poly(1,3-Cyclohexadiene) (PCHD) Homo- and Block Copolymers: Controlled Processability and Properties

Conjugated polymers have been used as solid-state materials for a variety of opto-electronic applications. Thus, their processability in a number of device fabrication protocols is an important consideration. In this report, we indicate our results on the synthesis of conjugated poly-p-phenylene (PPP) materials derived from poly(1,3-cyclohexadiene) (PCHD). The precursor PCHD polymers were synthesized by living anionic polymerization to produce homo-and block copolymer configurations with polystyrene. We have used a variety of initiators, solvent, and temperature conditions to determine the right parameters for obtaining narrow MWD polymers. The conditions for polymerization determined the ratio of 1,2 and 1,4 isomers in the microstructure. We then proceeded with conversion to PPP derivatives using a dehydrogenation reaction with chloranil. Our results indicate a systematic conversion to a conjugated polymer with increased solubility and photoluminescence properties. The microstructure, MW and block copolymer composition affecting the processability and conversion properties dramatically.

Prospective phase II study of chemoembolization with drug-eluting beads for hepatic neuroendocrine metastases: Interim analysis

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Background: To evaluate safety and efficacy of transarterial chemoembolization with doxorubicin eluting beads (DEB-TACE) in 30 patients with hepatic neuroendocrine metastases (NET) in a prospective phase II study. We report the interim analysis on 10 patients.

Methods: Patients who met inclusion criteria (NET liver-dominant metastases, ECOG 0-1, treatment naïve) underwent up to 4 DEB-TACE sessions (100-300 micron beads loaded with up to 100mg of doxorubicin) within a 6-month period. Statistical plan included interim analysis of initial 10 patients to assess therapeutic efficacy (defined as objective response≥50%). Tumor response was assessed by MR imaging 1 month after treatment using contrast-enhancement (EASL) and tumor size (RECIST). Safety was assessed by NCI Common Terminology Criteria.

Results: DEB-TACE was successfully performed in 10 patients (22 targeted lesions). Patient characteristics included mean age 65 yrs; ECOG 0/1 (6/4); carcinoid syndrome (n=2); tumor burden range (4-75%), and mean targeted tumor size 4.8 cm (range 1.2-10.2). At one month follow-up (n=9), Grade 3 toxicities consisted of hyperglycemia (n=3), abdominal pain (n=3), fatigue (n=1), biloma (n=1) and elevated ALT (n=1). Note that four patients had Grade 2 bilomas, which occurred in the setting of small lesions (<2cm), diffuse disease with very low tumor burden (near military pattern), and single lesion ≥ 5cm. Tumor response using MR imaging at 1 month-follow-up revealed a mean treated tumor decrease in size of 7% (p=0.03), and a mean decrease in contrast-enhancement of 59% (p<0.0001). Using RECIST, partial response was achieved in 1 patient (11%), whereas 8 patients (89%) had stable disease. Using EASL criteria, 7 patients (78%) had objective tumor response and 2 (12%) had stable disease.

Conclusions: Interim analysis shows therapeutic efficacy of DEB-TACE in liver-dominant NET metastases. Early recommendation suggests DEB-TACE may be best suited for NET patients with multifocal disease or diffuse disease with large tumor burden.

[Table: see text]

No significant financial relationships to disclose.

Standardized treatment and follow-up protocol of hepatocellular carcinoma with transcatheter arterial chemoembolization: Survival, clinical, and tumor control outcome over 12 years at a U.S. center

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Background: To report the outcome of the care of patients with hepatocellular carcinoma (HCC) treated with standardized transcatheter arterial chemomembolization (TACE), with a focus on tumor response according to Response Evaluation Criteria in Solid Tumors (RECIST), progression of underlying cirrhosis [Child-Pugh (CP) score], time to progression (TTP) and survival from 1996 to 2008. Methods: TACE was performed on 365 patients in 1,035 sessions. According to a standardized protocol, all patients received imaging (MRI and/or CT) at baseline and at 4–6 weeks after each session and were clinically, biochemically and radiologically evaluated before each session. Liver disease status was evaluated before and at the end of the treatment period with the CP class system and tumor size measurements according to the RECIST. The Barcelona Clinic Liver Cancer (BCLC) classification was employed to stage patients. Three chemotherapeutic agents and lipiodol, followed by non-occlusive embolization were utilized during TACE. Complete vessel occlusion was avoided at all times. Overall survival and TTP were calculated according to the Kaplan-Meier method. The log-rank test was used to calculate differences between groups in the subgroup analysis. Results: All patients (78% male, mean age: 63.5 years) received an average of 3 TACE sessions (range: 1–10 and average interval between sessions: 75 days). Sixty six percent of patients had 3 or more tumors, with a mean tumor size at presentation of 6.9 cm. Partial response was achieved in 32 % of patients, while 65% remained stable over the course of 3 TACEs. CP class remained unchanged for 75% of patients over the above course of treatment. Median survival for the entire cohort was 20 months and TTP was 14 months. Interestingly, advanced BCLC patients achieved similar tumor response (PR:33%), TTP of 13.4 months and median survival of 13.7 months. Conclusions: Patients with HCC treated with the aforementioned standardized TACE and follow-up protocol showed durable survival, stable liver disease and effective tumor control.

[Table: see text]

Weight cycling in a very low-calorie diet programme has no effect on weight loss velocity, blood pressure and serum lipid profile

BACKGROUND

Many dieters lose and regain weight many times. It is unclear whether weight cycling is associated with adverse metabolic alterations or becomes more difficult with each attempt.

METHODS

From 1988 to 2000, 2474 obese patients enrolled in our outpatient weight loss programme using a very low-calorie diet. Caloric intake consisted of meal replacement supplying 700-800 cal/day.

RESULTS

Our search distinguished 480 patients who had restarted the weight reduction programme at least once and up to four times (restarts). All subjects remained on the programme for 2 weeks or more each time. Mean initial weight loss was 21.3 kg for women and 28.8 kg for men. Rate of weight loss on first restart was not different from initial weight loss for women [1.6 vs. 1.4 kg/week; not significant (NS)] or for men (2.2 vs. 2.1 kg/week; NS). Of the 480 patients, 85 women and 51 men entered the programme three times. Rate of weight loss was similar for all three entries (1.4, 1.6 and 2.1 kg/week for first, second and third entry in women, NS; 2.1, 2.1 and 2 kg/week for men, NS). Only 20 women and 18 men entered the programme four times. The rate of weight loss was again similar for both men (NS) and women (NS) during each re-entry. Cardiovascular risk factors including lipid profile and blood pressure were not adversely affected by weight cycling. In fact, lipid levels were lower at each restart.

CONCLUSIONS

The present study refutes the hypothesis that repeated dieting makes further dieting efforts more difficult.

Feasibility of a low-fat/high-fiber diet intervention with soy supplementation in prostate cancer patients after prostatectomy

OBJECTIVES

To evaluate the feasibility and long-term compliance with a low-fat diet supplemented with soy protein in men at increased risk for recurrence after radical prostatectomy.

DESIGN

Randomized, control study.

SETTING

Academic center in USA.

SUBJECT

Forty men who had undergone radical prostatectomy and were at increased risk for recurrence.

INTERVENTION

Low-fat (15% fat), high-fiber (18 g/1000 kcal) diet supplemented with 40 g soy protein isolate (n=26) was compared to USDA recommended diet (n=14).

RESULTS

Over 4 years, subjects in the intervention group but not in the control group made and sustained significant changes in their diet as measured by the dietary assessment instruments and urinary isoflavone excretion. In the intervention group, dietary fat intake was reduced from 33.46+/-1.27% energy/day to 21.04+/-1.74% (P<0.05), fiber intake increased from 14.6+/-1.06 to 21.05+/-2.29 g/day. The insulin growth factor-1 (IGF-1) level was decreased from 260.4+/-8.6 ng/ml at baseline to 220.5+/-7.9 ng/ml at 6 months (P<0.05) in the intervention group with no significant change in the control group. An ex vivo assay demonstrated inhibition of LNCaP cell growth (-20.0+/-7.7%, P<0.05) by sera from patients in the intervention group after 6 months of dietary change compared to baseline.

CONCLUSION

These data suggest that long-term low-fat dietary interventions as part of prospective randomized trials in prostate cancer survivors are feasible, and lead to reductions in circulating hormones or other growth factors stimulating prostate cancer growth ex vivo.

Increased target specificity of anti-HER2 genospheres by modification of surface charge and degree of PEGylation

Genospheres are cationic lipid-nucleic acid nanoparticles prepared by the assembly of the lipids and nucleic acids from an aqueous/organic liquid monophase that independently dissolves the components, where the resultant particles are homogeneously sized (70-110 nm), with efficiently incorporated and protected DNA. In the present study, we demonstrate pH-dependent modulation of the Genosphere surface charge using pH-titratable lipids. By incorporation of the lipids with titratable anionic or imidazole headgroups, Genospheres with neutral or anionic surface charge at neutral pH were produced and compared for cellular uptake and transfection of a reporter gene (luciferase) in culture of breast cancer cells. The extent of particle-cell association was also studied by fluorescent microscopy and quantified by cytofluorometery. The effects of Genosphere surface modification with poly(ethylene glycol) (molecular weight 2000) at low (0.5 mol %) and high (5 mol %) grafting densities, as well as the effects of HER2-receptor-directed targeting by an internalizable anti-HER2 scFv F5, linked via PEG spacer, were also studied. Inclusion in the Genosphere formulation of pH-titratable lipids CHEMS (cholesteryl hemisuccinate), CHIM (1-(3-(cholesteryloxycarbonylamino)propyl)imidazole), or DSGG (1,2-distearoyl-sn-glycero-3-hemiglutarate) rendered the particles surface-charge neutral or slightly anionic at neutral pH, and cationic at mildly acidic pH, as shown by zeta-potential measurements. In HER2-targeted systems, transfection activity and target specificity with HER2-overexpressing SKBR-3 breast cancer cells were dependent on Genosphere surface charge and PEGylation. The highest target specificity correlated with low cationic charge at neutral pH, while incorporation of 5 mol % PEG-lipid had only minor effects on Genosphere-cell association, internalization, and transfection activity. The implications of this work for potential in vivo applications are discussed.

Utilization of an alternative Communication Device using the Anal Sphincter (CDAS)

The purpose of this study was to invent a new communication system for terminal amyotrophic lateral sclerosis (ALS) patients who are in a state of complete motor paralysis with intact sensory and cognitive functions whose speech are disrupted due to the weakness of muscles involved in speaking and/ or to tracheostomy and ventilator dependence.

[Histology of liver lesions due to Schistosoma mekongi. About six cases with severe portal hypertension operated in Cambodia]

Schistosomiasis mekongi was shown to be endemic, along the Mekong River, in northern Cambodia, affecting many patients with portal hypertension. Surgical procedures were proposed to some patients with digestive haemorrhage history to avoid fatal recurrence. The aim of our study was to evaluate the intensity of the liver fibrosis among these patients. During surgical treatment, liver biopsies were collected, fixed in Bouin or in formalin and processed at the Institut Pasteur of Cambodia. Sections were stained by H&E, Masson's trichrome, PAS, Ziehl-Neelsen's method and Congo Red. A total of six biopsies from patients aged 16-36 were analysed. There was complete disorganization of hepatic architecture with fibrous enlargement of portal tracts and some portal-portal bridging fibrosis, but there was no cirrhosis. In portal areas, there was blood vessel congestion and thrombosis with inflammation. Bile ducts were normal. In the parenchyma, congestion of sinusoidal capillaries was combined with focal mononuclear inflammatory infiltrate. There was no steatosis, no necrosis, no cholestasis, no iron accumulation and no amyloidosis. Numerous eggs of Schistosoma mekongi were observed in five cases, mostly in fibrous areas and more rarely in the parenchyma. Eggs were round or oval, measuring 60 x 40 microns with an acid-fast thin hyaline wall. Some eggs were surrounded by epithelioid and giant cell reaction. In conclusion, our findings illustrated a surprisingly high degree of fibrosis among young adults which contrasts with other schistosomiasis.

Genospheres: self-assembling nucleic acid-lipid nanoparticles suitable for targeted gene delivery

We describe the assembly of a cationic lipid-nucleic acid nanoparticle from a liquid monophase containing water and a water miscible organic solvent where both lipid and DNA components are separately soluble prior to their combination. Upon removal of the organic solvent, stable and homogenously sized (70-100 nm) lipid-nucleic acid nanoparticles (Genospheres) were formed. The low accessibility (<15%) of the nanoparticle-encapsulated DNA to a DNA intercalating dye indicated well-protected nucleic acids and high DNA incorporation efficiencies. It was demonstrated that Genospheres could be stably stored under a variety of conditions including a lyophilized state where no appreciable increase in particle size or DNA accessibility was observed following reconstitution. Finally, Genospheres were made target-specific by insertion of an antibody-lipopolymer (anti-HER2 scFv (F5)-PEG-DSPE) conjugate into the particle. The target specificity (>100-fold) in HER2 overexpressing SK-BR-3 breast cancer cells was dependent on the degree of PEGylation, where the incorporation of high amounts of PEG-lipid on the particle surface (up to 5 mol%) had only a minor effect on the transfection activity of the targeted Genospheres. In summary, this work describes a novel, readily scalable method for preparing highly stable immunotargeted nucleic acid delivery vehicles capable of achieving a high degree of specific transfection activity.