Intranasal delivery of mouse [D-Leu-4]-OB3, a synthetic peptide amide with leptin-like activity, improves energy balance, glycaemic control, insulin sensitivity and bone formation in leptin-resistant C57BLK/6-m db/db mice

BACKGROUND

We have recently shown that intranasal administration of mouse [D-Leu-4]-OB3 reconstituted in Intravail(®) to male Swiss Webster mice resulted in significantly higher uptake and bioavailability when compared with commonly used injection methods of delivery.

AIM AND METHODS

In this study, we examined the effects of intranasal delivery of mouse [D-Leu-4]-OB3 in Intravail(®) on energy balance, glucose regulation, insulin secretion and serum levels of osteocalcin, a specific and sensitive marker of bone formation. Genetically obese C57BLK/6-m db/db mice were allowed food and water ad libitum and given either Intravail(®) alone or mouse [D-Leu-4]-OB3 in Intravail(®) for 14 days by intranasal instillation.

RESULTS

Mouse [D-Leu-4]-OB3 reduced body weight gain, daily food intake, daily water intake and serum glucose by 11.5, 2.2, 4.0 and 61.9%, respectively. Serum insulin levels in db/db mice given mouse [D-Leu-4]-OB3 were approximately threefold lower than those in mice receiving Intravail(®) alone. Mouse [D-Leu-4]-OB3 elevated serum osteocalcin in db/db mice by 28.7% over Intravail(®) treated control mice.

CONCLUSIONS

The results of our study indicate that intranasal delivery of biologically active mouse [D-Leu-4]-OB3 in Intravail(®) is feasible and has significant effects on regulating body weight gain, food and water intake, serum glucose, insulin sensitivity and bone formation in leptin-resistant C57BLK/6-m db/db mice.

Fabrication of unique tungsten tips by the self-descending phenomenon of menisci

This paper describes the fabrication of tungsten tips with high aspect ratios for use as probes in scanning tunneling microscopy. A Teflon bath with the hydrophobic property is employed as an etching bath instead of the use of conventional glass beakers. Hydrophobicity of the Teflon bath with a unique shape causes a gradual decrease of the meniscus during the etching process. Owing to this effect, tungsten tips with high aspect ratios and resonance frequencies can be easily fabricated without the help of any additional mechanical and electrical parts. The fabrication of W tips with radii of curvature down to 20 nm is demonstrated using the new method. The reproducibility of the unique W-tip structure is also experimentally confirmed.

The structure of graphite oxide: investigation of its surface chemical groups

The structure of graphite oxide (GO) has been systematically studied using various tools such as SEM, TEM, XRD, Fourier transform infrared spectroscopy (FT-IR), X-ray photoemission spectroscopy (XPS), (13)C solid-state NMR, and O K-edge X-ray absorption near edge structure (XANES). The TEM data reveal that GO consists of amorphous and crystalline phases. The XPS data show that some carbon atoms have sp(3) orbitals and others have sp(2) orbitals. The ratio of sp(2) to sp(3) bonded carbon atoms decreases as sample preparation times increase. The (13)C solid-state NMR spectra of GO indicate the existence of -OH and -O- groups for which peaks appear at 60 and 70 ppm, respectively. FT-IR results corroborate these findings. The existence of ketone groups is also implied by FT-IR, which is verified by O K-edge XANES and (13)C solid-state NMR. We propose a new model for GO based on the results; -O-, -OH, and -C=O groups are on the surface.

Animal pigment bilirubin discovered in plants

The bile pigment bilirubin-IXalpha is the degradative product of heme, distributed among mammals and some other vertebrates. It can be recognized as the pigment responsible for the yellow color of jaundice and healing bruises. In this paper we present the first example of the isolation of bilirubin in plants. The compound was isolated from the brilliant orange-colored arils of Strelitzia nicolai, the white bird of paradise tree, and characterized by HPLC-ESMS, UV-visible, (1)H NMR, and (13)C NMR spectroscopy, as well as comparison with an authentic standard. This discovery indicates that plant cyclic tetrapyrroles may undergo degradation by a previously unknown pathway. Preliminary analyses of related plants, including S. reginae, the bird of paradise, also revealed bilirubin in the arils and flowers, indicating that the occurrence of bilirubin is not limited to a single species or tissue type.

Oral delivery of mouse [d-Leu-4]-OB3, a synthetic peptide amide with leptin-like activity, in male C57BL/6J wild-type and ob/ob mice: effects on energy balance, glycaemic control and serum osteocalcin levels

BACKGROUND

We have recently shown that intranasal administration of mouse [d-Leu-4]-OB3 reconstituted in Intravail to male Swiss Webster mice resulted in significantly higher bioavailability than commonly used injections methods of delivery. The absorption profile associated with intranasal delivery of mouse [d-Leu-4]-OB3 showed an early peak representing absorption across the nasal mucosa, and a later peak suggesting a gastrointestinal site of uptake.

AIM AND METHODS

In the present study, we examined the effects of orally administered (by gavage) mouse [d-Leu-4]-OB3 on energy balance, glycaemic control and serum osteocalcin levels in male C57BL/6J wild-type and ob/ob mice allowed food and water ad libitum or calorie restricted by 40% of normal intake.

RESULTS

In wild-type mice fed ad libitum, oral delivery of mouse [d-Leu-4]-OB3 reduced body weight gain, food intake and serum glucose, by 4.4, 6.8 and 28.2% respectively. Serum osteocalcin levels and water intake were essentially the same in control and treated wild-type mice. In ob/ob mice fed ad libitum, mouse [d-Leu-4]-OB3 reduced body weight gain, food intake, water intake and serum glucose by 11.6, 16.5, 22.4 and 24.4% respectively. Serum osteocalcin in ob/ob mice treated with mouse [d-Leu-4]-OB3 was elevated by 62% over controls. Calorie restriction alone caused significant weight loss in both wild-type (9.0%) and ob/ob (4.8%) mice, and mouse [d-Leu-4]-OB3 did not further enhance this weight loss. As expected, serum glucose levels in wild-type and ob/ob mice were significantly reduced by calorie restriction alone. Mouse [d-Leu-4]-OB3 further reduced serum glucose in wild-type mice and normalized levels in ob/ob mice. Calorie restriction alone reduced serum osteocalcin levels by 44.2% in wild-type mice and by 19.1% in ob/ob mice. Mouse [d-Leu-4]-OB3 prevented this decrease in groups of mice.

CONCLUSIONS

The results of this study suggest that oral delivery of mouse [d-Leu-4]-OB3 in Intravail is possible and may have potential not only as an alternative therapy in the treatment of human obesity and some of its associated metabolic dysfunctions, but also may help to prevent and/or reverse at least some of the bone loss which accompanies osteoporosis, anorexia nervosa and other wasting diseases.

Species-specific injury-induced cell proliferation in the hippocampus and subventricular zone of food-storing and nonstoring wild birds

Cells are continuously born and incorporated into the adult hippocampus (HP). Adult neurogenesis might act to increase the total number of cells or replace dead cells. Thus, neurogenesis might be a primary factor in augmenting, maintaining, or even recovering functions. In zebra finches, HP injury increases cell proliferation in the HP and stem cell rich subventricular zone (SVZ). It is unknown what effect injury has on a species dependent upon the HP for survival in the wild. In food-storing birds, recovery of caches is seasonal, necessary for survival, dependent upon the HP and is concomitant with a peak in HP neurogenesis. During the fall, food-storing black-capped chickadees (BCCs) and nonstoring dark-eyed juncos (DEJs) were captured and given a unilateral penetrating lesion to the HP one day later. On day 3, birds were injected with the mitotic marker 5-bromo-2'-deoxyuridine (BrdU) and perfused on day 10. If unlesioned, more BrdU-labeled cells were observed in the HP and SVZ of BCCs compared to DEJs, indicating higher innate cell proliferation or incorporation in BCCs. If lesioned, BrdU-labeled cells increased in the injured HP of both species; however, lesions caused larger increases in DEJs. DEJs also showed increases in BrdU-labeled cells in the SVZ and contralateral HP. BCCs showed no such increases on day 10. Thus, during the fall food-storing season, storers showed suppressed injury-induced cell proliferation and/or reduced survival rates of these new cells compared to nonstorers. These species differences may provide a useful model for isolating factors involved in cellular responses following injury.

Understanding the medical and nonmedical value of diagnostic testing

OBJECTIVES

To develop a framework for defining the potential value of diagnostic testing, and discuss its implications for the health-care delivery system.

METHODS

We reviewed the conceptual and empirical literature related to the valuing of diagnostic tests, and used this information to create a framework for characterizing their value. We then made inferences about the impact of this framework on health insurance coverage, health technology assessment, physician-patient relationships, and public health policy.

RESULTS

Three dimensions can effectively classify the potential value created by diagnostic tests: 1) medical value (impact on treatment decisions); 2) planning value (affect on patients' ability to make better life decisions); and 3) psychic value (how test information affects patients' sense of self). This comprehensive framework for valuing diagnostics suggests that existing health technology assessments may systematically under- or overvalue diagnostics, leading to potentially incorrect conclusions about cost-effectiveness. Further, failure to account for all value dimensions may lead to distorted payments under a value-based health-care system.

CONCLUSIONS

The potential value created by medical diagnostics incorporates medical value as well as value associated with well-being and planning. Consideration of all three dimensions has important implications for technology assessment and value-based payment.

Trends in healthcare utilization among older Americans with colorectal cancer: a retrospective database analysis

Background

Analyses of utilization trends (cost drivers) allow us to understand changes in colorectal cancer (CRC) costs over time, better predict future costs, identify changes in the use of specific types of care (eg, hospice), and provide inputs for cost-effectiveness models. This retrospective cohort study evaluated healthcare resource use among US Medicare beneficiaries diagnosed with CRC between 1992 and 2002.

Methods

Cohorts included patients aged 66+ newly diagnosed with adenocarcinoma of the colon (n = 52,371) or rectum (n = 18,619) between 1992 and 2002 and matched patients from the general Medicare population, followed until death or December 31, 2005. Demographic and clinical characteristics were evaluated by cancer subsite. Resource use, including the percentage that used each type of resource, number of hospitalizations, and number of hospital and skilled nursing facility days, was evaluated by stage and subsite. The number of office, outpatient, and inpatient visits per person-year was calculated for each cohort, and was described by year of service, subsite, and treatment phase. Hospice use rates in the last year of life were calculated by year of service, stage, and subsite for CRC patients who died of CRC.

Results

CRC patients (mean age: 77.3 years; 44.9% male) used more resources than controls in every category (P < .001), with the largest differences seen in hospital days and home health use. Most resource use (except hospice) remained relatively steady over time. The initial phase was the most resource intense in terms of office and outpatient visits. Hospice use among patients who died of CRC increased from 20.0% in 1992 to 70.5% in 2004, and age-related differences appear to have evened out in later years.

Conclusion

Use of hospice care among CRC decedents increased substantially over the study period, while other resource use remained generally steady. Our findings may be useful for understanding CRC cost drivers, tracking trends, and forecasting resource needs for CRC patients in the future.

Reinvestigation of the direct two-proton decay of the long-lived isomer 94Ag(m) [0.4 s, 6.7 MeV, (21+)]

An attempt to confirm the reported direct one-proton and two-proton decays of the (21+) isomer at 6.7(5) MeV in 94Ag has been made. The 0.39(4) s half-life of the isomer permitted use of a helium-jet system to transport reaction products from the 40Ca + (nat)Ni reaction at 197 MeV to a low-background area; 24 gas DeltaE-(Si)E detector telescopes were used to identify emitted protons down to 0.4 MeV. No evidence was obtained for two-proton radioactivity with a summed energy of 1.9(1) MeV and a branching ratio of 0.5(3)%. Two groups of one-proton radioactivity from this isomer had also been reported; our data confirm the lower energy group at 0.79(3) MeV with its branching ratio of 1.9(5)%.

Factors associated with improved survival among older colorectal cancer patients in the US: a population-based analysis

Background

The purpose of this study was to estimate the relative impact of changes in demographics, stage at detection, treatment mix, and medical technology on 5-year survival among older colorectal cancer (CRC) patients.

Methods

We selected older patients diagnosed with CRC between 1992 and 2000 from the SEER-Medicare database and followed them through 2005. Trends in demographic characteristics, stage at detection and initial treatment mix were evaluated descriptively. Separate multivariate logistic regression models for colon (CC) and rectal cancer (RC) patients were estimated to isolate the independent effects of these factors along with technological change (proxied by cohort year) on 5-year survival.

Results

Our sample included 37,808 CC and 13,619 RC patients (combined mean ± SD age: 77.2 ± 7.0 years; 55% female; 87% white). In recent years, more CC patients were diagnosed at Stage I and fewer at Stages II and IV, and more RC patients were diagnosed at Stage I and fewer at Stages II and III. CC and RC patients diagnosed in later years were slightly older with somewhat better Charlson scores and were more likely to be female, from the Northeast, and from areas with higher average education levels. Surgery alone was more common in later years for CC patients while combined surgery, chemotherapy, and radiotherapy was more common for RC patients. Between 1992 and 2000, 5-year observed survival improved from 43.0% to 46.3% for CC patients and from 39.4% to 42.2% for RC patients. Multivariate logistic regressions indicate that patients diagnosed in 2000 had significantly greater odds of 5-year survival than those diagnosed in 1992 (OR: 1.35 for CC, 1.38 for RC). Our decomposition suggests that early detection had little impact on survival; rather, technological improvements (e.g., new medical technologies or more effective use of existing technologies) and changing demographics were responsible for the largest share of the change in 5-year survival in CC and RC between 1992 and 2000.

Conclusion

Technological advances and changes in patient demographics had the largest impact on improved colorectal cancer survival during the study period.

Comparison of the characteristics for in-hospital and out-of-hospital ischaemic strokes

BACKGROUND AND PURPOSE

Patients who are being admitted to a hospital due to diseases other than stroke may develop a stroke (in-hospital stroke; IHS).

METHODS

We enrolled 111 consecutive patients who developed IHS outside a neurology ward during a 5-year period at a single hospital. The frequency, characteristics, and outcomes for IHS patients were compared with patients who develop ischaemic stroke outside of the hospital (out-of-hospital stroke; OHS).

RESULTS

Forty-six percent of IHS occurred in the department of cardiology or cardiovascular surgery and 60% were associated with surgery or procedures. In comparison with the OHS patient group, the IHS patient group showed an increased frequency of cardiac disease, leukocytosis, and anemia. Cardioembolism, stroke of other determined etiologies, and an incomplete evaluation were more common in the IHS group, whereas large artery atherosclerosis was more frequent in the OHS group. The IHS group had up to a 10-fold higher mortality than the OHS group, with sepsis being the most common cause of death in the IHS group.

CONCLUSIONS

IHS has distinct etiologies and stroke mechanisms from OHS. The prevention and management of infection could decrease mortality in IHS patients.

What are the total costs of surgical treatment for uterine fibroids?

OBJECTIVE

To investigate the direct and indirect costs of uterine fibroid (UF) surgery.

METHODS

Data were obtained from the MarketScan Commercial Claims and Encounters databases for 1999-2004. Our sample included 22,860 women with insurance coverage who were treated surgically for UF and 14,214 women who were treated nonsurgically for UF. Medical care costs and missed workdays were divided into baseline (1 year prior to surgery) and postoperative (1 year after surgery) periods. For a subsample of women, we calculated average annual costs 3 years before and after their surgery.

RESULTS

Of patients electing surgery, 85.9% underwent hysterectomy, 7.6% myomectomy, 4.9% endometrial ablation, and 1.6% uterine artery embolization (UAE). Women undergoing UAE incurred the highest medical care costs in the operative year ($16,430 unadjusted, $20,634 adjusted for confounders), followed by hysterectomy ($15,180 unadjusted, $17,390 adjusted), myomectomy ($14,726 unadjusted, $18,674 adjusted), and endometrial ablation ($12,096 unadjusted, $13,019 adjusted). Women treated nonsurgically incurred costs of $7,460 unadjusted and $8,257 adjusted during the year after they were diagnosed with UF. Three years after surgery, patients treated with hysterectomy had the lowest annual costs. Missed workdays in the year after surgery were high, resulting in significant losses to employers in the magnitude of $6,670-$25,229, depending on treatment, values assigned to missed workdays, and whether the analyses adjusted for confounders.

CONCLUSIONS

UF surgical treatment costs were high. Absenteeism and disability were important components of the cost burden of UF treatment for women, their employers, and the healthcare system.

Unravelling the evolution of autumn colours: an interdisciplinary approach

Leaf colour change is commonly observed in temperate deciduous forests in autumn. This is not simply a side effect of leaf senescence, and, in the past decade, several hypotheses have emerged to explain the evolution of autumn colours. Yet a lack of crosstalk between plant physiologists and evolutionary ecologists has resulted in slow progress, and so the adaptive value of this colour change remains a mystery. Here we provide an interdisciplinary summary of the current body of knowledge on autumn colours, and discuss unresolved issues and future avenues of research that might help reveal the evolutionary meaning of this spectacle of nature.

Cost-effectiveness of magnetic resonance guided focused ultrasound for the treatment of uterine fibroids

OBJECTIVES

The aim of this study is to evaluate the cost-effectiveness of Magnetic Resonance Guided Focused Ultrasound (MRgFUS) compared with alternative treatments for uterine fibroids in the United States.

METHODS

We used techniques of decision analysis and data from secondary sources to develop and estimate an economic model of the management of uterine fibroids among premenopausal women. Patients in the model receive treatment with MRgFUS, uterine artery embolization (UAE), abdominal myomectomy, hysterectomy, or pharmacotherapy. The model predicts total costs (including subsequent procedures) and quality-adjusted life-years (QALYs) for each treatment strategy over a lifetime horizon, discounted at 3 percent, from a societal perspective. Data on treatment efficacy and safety were obtained from published and unpublished studies. Costs (2005 US$) were obtained from an analysis of a large administrative database and other secondary sources. Lost productivity costs were included in the base-case analysis, but excluded in a sensitivity analysis.

RESULTS

UAE was associated with the most QALYs (17.39), followed by MRgFUS (17.36), myomectomy (17.31), hysterectomy (17.18), and pharmacotherapy (16.70). Pharmacotherapy was the least costly strategy ($9,200 per patient), followed by hysterectomy ($19,800), MRgFUS ($27,300), UAE ($28,900), and myomectomy ($35,100). Incremental cost-effectiveness ratios (cost per QALY gained) were $21,800 for hysterectomy, $41,400 for MRgFUS, and $54,200 for UAE; myomectomy was more costly and less effective than both MRgFUS and UAE. Results were sensitive to MRgFUS recurrence rates, MRgFUS procedure costs, and assumptions about quality of life following hysterectomy.

CONCLUSIONS

Our findings suggest that MRgFUS is in the range of currently accepted criteria for cost-effectiveness, along with hysterectomy and UAE.

Identification of glutathione conjugates and mercapturic acids of 1,2-dibromopropane in female BALB/c mice by liquid chromatography-electrospray ionization tandem mass spectrometry

Based on recent results that 1,2-dibromopropane (1,2-DBP) causes hepatotoxicity and immunotoxicity in female BALB/c mice as well as a reduction of hepatic glutathione levels, the possible formation of glutathione conjugates and mercapturic acids of 1,2-DBP was investigated in vivo in the present studies. The following four metabolites were identified in the liver at 12 h after treatment with 1,2-DBP, by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI/MS): M1, 2-hydroxypropylglutathione; M2, 2-oxopropylglutathione; M3, N-acetyl-S-(2-hydroxypropyl)-L-cysteine; and M4, N-acetyl-S-(2-oxopropyl)-L-cysteine. Ions of individual conjugates were observed at m/z 366, 364, 222 and 220, respectively. Characteristic product ions at m/z 237, 217, 204 and 202 for the identification of M1, M2, M3 and M4 were observed, respectively. In the sera isolated from the same animals, only mercapturic acids (M3 and M4) were observed by LC-ESI/MS. When female BALB/c mice were treated orally with 1,2-DBP at doses of 150, 300 and 600 mg kg(-1) once for 12 h, the production of glutathione conjugates and mercapturic acids in liver was apparently dose dependent, as were the concentrations of them in sera. When the production of metabolites from 1,2-DBP was investigated in liver following oral treatment with 600 mg kg(-1) 1,2-DBP for 6, 12, 24 and 48 h, metabolite concentrations were greatest at the first time point (6 h). The results explain the authors' previous studies that oral treatment with 1,2-DBP reduces the hepatic content of glutathione.

The direct and indirect cost burden of clinically significant and symptomatic uterine fibroids

OBJECTIVE

To estimate direct medical costs and indirect (productivity related) for women age 25 to 54 who had clinically significant and symptomatic uterine fibroids (UF).

METHODS

We compared direct medical expenditures among 30,659 women who had clinically significant and symptomatic UF to expenditures among an equal number of matched controls who did not. We also compared indirect costs for a sub-sample of 910 employed women in each group. Regression analyses controlled for demographic and casemix factors.

RESULTS

Mean 12-month direct medical costs for women with UF were $11,720 versus $3257 for controls, and mean 12-month indirect costs for women with UF were $11,752 versus $8083 for controls. Differences were statistically significant (P<0.0001).

CONCLUSIONS

UF is a costly disorder and merits thought as interventions are considered to improve women's health and productivity.