Sex-Specific Associations of Dietary Iron Intake with Brain Iron Deposition on Imaging and Incident Dementia: A Prospective Cohort Study

OBJECTIVES

The study aimed to evaluate the association of dietary iron intake with incident dementia and brain iron deposition.

DESIGN/SETTING/PARTICIPANTS

We included dementia-free participants from the UK Biobank who completed at least one 24-hour dietary recall at study baseline (2009-2012) and were followed up to 2021. Incident dementia was determined through linkage to medical records and death registries. Brain MRI was conducted in a subgroup of participants since 2014, with T2* measurements being used as indicators of brain iron deposition.

MEASUREMENTS

Cox proportional hazard models were used to assess the associations of high (top quintile) and low (bottom quintile) versus medium (quintile 2 to 4) level of dietary iron intake with incident dementia, respectively. Linear regression was applied to assess the relations between dietary iron intake and brain T2* measurements.

RESULTS

During follow-up (mean = 9.5 years), a total of 1,454 participants (650 women and 804 men) developed dementia among 191,694 participants (55.0% female; mean age, 56.2 years). When adjusted for sociodemographic, lifestyle, and other dietary factors, participants with low dietary iron intake (< 10.05 mg/day) had a significantly higher dementia risk (hazard ratio [HR], 1.50, 95% confidence interval [CI], 1.19-1.89), while the relation for high intake (> 16.92 mg/day) was non-significant (HR, 1.16, 95% CI, 0.92-1.46). A significant gender difference (P-interaction < 0.001) was observed, with a U-shaped association in male participants (HR for low vs. medium, 1.56, 95% CI, 1.14-2.13; HR for high vs. medium, 1.39, 95% CI, 1.03 - 1.88; P-nonlinearity < 0.001) and no significant association in females, regardless of their menopause status. In general, dietary iron intake was not related to T2* measurements of iron deposition in most brain regions.

CONCLUSION

Our findings suggested a U-shape relationship between dietary iron intake and risk of dementia among males, but not females.

Expression of inducible nitric oxide synthase in mast cells contributes to the regulation of inflammatory cytokines in irritable bowel syndrome with diarrhea

BACKGROUND

Nitric oxide (NO) and mast cells (MCs) are possibly involved in the development of irritable bowel syndrome (IBS), but details on their role and interactions still remain undetermined. We aimed to investigate the expression of inducible NO synthase (iNOS) in MCs of the colon of IBS with diarrhea (IBS-D), and elucidated a potential role of NO in the differential regulation of cytokines in MCs.

METHODS

Colonic mucosal biopsies of 19 IBS-D patients and 16 healthy controls were collected. The expression of tryptase and iNOS was investigated by immunohistochemistry, Western blotting, and real-time PCR. Effects of NO on the expression of cytokines in rat bone marrow MCs (BMMCs) were examined using a cytokine array by NG-nitro-l-arginine methyl ester (L-NAME) treatment.

KEY RESULTS

Immunohistochemistry for tryptase revealed an increase in number of MCs with extensive iNOS expression in the colonic mucosa of IBS-D. Tryptase, iNOS and interleukin (IL)-1β mRNA and protein levels were upregulated in IBS-D compared with healthy controls. Specifically, a positive correlation between tryptase and iNOS protein expression was observed in the colon of IBS-D (r = 0.667, p < 0.05). Supernatant from IBS-D increased iNOS expression in BMMCs. Antibody array showed that agrin, beta-nerve growth factor, fractalkine, granulocyte-macrophage colony-stimulating factor, IL-1β, IL-1R6, IL-13, leptin, tumor necrosis factor alpha were suppressed, and cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2α, CINC-3, monocyte chemotactic protein-1, matrix metalloproteinase-8 were strongly produced in L-NAME treated BMMCs, comparable to levels in the control group.

CONCLUSIONS & INFERENCES

Our findings provide new evidence that NO is able to regulate many cytokines in MCs that may be involved in the development of IBS.

Erythrocyte trans-fatty acids, type 2 diabetes and cardiovascular risk factors in middle-aged and older Chinese individuals

AIMS/HYPOTHESIS

Few data are available about intakes and food sources of trans-fatty acids (TFAs) or their associations with cardiometabolic outcomes in Asian people who consume a prudent diet but are experiencing rapid nutritional transitions. We aimed to investigate the relationships between TFA biomarkers and type 2 diabetes and cardiovascular risk factors in Chinese individuals.

METHODS

Erythrocyte fatty acids were measured by gas chromatography among 3,107 men and women (50-70 years) recruited from urban and rural areas in Beijing and Shanghai, China.

RESULTS

Total trans-18:1 and two trans-18:2 isomers were detected and accounted for 0.37% of the total fatty acids in the erythrocytes. Concentrations of TFAs were higher in women than men, and in urban than rural residents. Of the TFAs, trans-18:1, but not trans-18:2, showed a modest association with dairy consumption (β = 0.27), but not with other foods. After adjustment for BMI, social-demographic, lifestyle and dietary factors and other TFAs, erythrocyte trans-18:1 was shown to be associated with a lower risk of type 2 diabetes (OR comparing extreme [first and fourth] quartiles 0.68, 95% CI 0.48, 0.97, p(trend) = 0.02), as well as 20-50% lower odds of central obesity, dyslipidaemia, hyperglycaemia, insulin resistance and chronic inflammation. In contrast, trans-18:2 fatty acids were positively associated with high triacylglycerol (p(trend) < 0.001) and LDL-cholesterol (p(trend) = 0.03) levels, but not with diabetes and other cardiometabolic risk factors.

CONCLUSIONS/INTERPRETATION

Among middle-aged and older Chinese individuals with overall low erythrocyte TFAs levels, trans-18:1 might serve as a marker of dairy intake. Higher trans-18:1 levels were associated with a lower risk of type 2 diabetes, whereas higher trans-18:2 levels were associated with dyslipidaemia.

[Clinical study on the early and short -- term use of antibiotics with broad spectrum in severely burned patients]

OBJECTIVE

To investigate the prevention and treatment effects of early and short -- term use of antibiotics with broad spectrum on postburn severe infection in severely burned patients.

METHODS

Thirty -- five burn patients with TBSA from 50% to 95% were enrolled in the study. The patients were divided into early prevention [20 cases, antibiotics were used started from 6 postburn hours (PBH)] and delayed prevention (15 cases, antibiotics were applied after 48 PBH) groups. Plasma levels of LPS, TNFa and IL -- 8 were dynamically monitored with the concomitant observation of clinical signs of postburn sepsis.

RESULTS

After major burns, the plasma levels of LPS, TNFalpha and IL -- 8 increased evidently and reached the peak values on 3 similar 5 postburn days (PBD). But the levels of all above factors in the early group were obviously lower than those in the delayed group (P < 0.05 similar 0.01). The incidencies of sepsis and internal organ complications within 2 postburn weeks were much lower in the early group than those in the delayed group (P < 0.05). The subeschar bacterial quantification on 4 similar 7 PBD was evidently lower in the early group than that in the delayed group (P < 0.01).

CONCLUSION

Early and short -- term use of antibiotics with broad spectrum in severely burned patients could effectively prevent postburn severe infection and lower down the incidence of internal organ complications.

Development of cationic liposome formulations for intratracheal gene therapy of early lung cancer

Regional (intratracheal or aerosol) delivery of cationic liposome-DNA complexes for gene therapy of lung disease offers distinct advantages over systemic (intravenous) administration. However, optimal formulations for early lung cancer treatment have not been established. Therefore, we investigated >50 different liposome and micelle formulations for factors that may affect their transcription efficiency and tested the ideal formulations in an in vivo mouse model. Our data showed that cationic liposomes were generally more effective at transfecting genes than were micelles of the same lipid composition, thus suggesting a role for the bilayer structure in facilitating transfection. In addition, the transfection efficiency of liposome-delivered genes was highly dependent upon the lipid composition, lipid/DNA ratio, particle size of the liposome-DNA complex, and cell lines used. By optimizing these factors in vitro and in vivo, we developed a novel liposome formulation (DP3) suitable for intratracheal administration. Using G67 liposome as control, we found that DP3 was more effective than G67 in vitro and as effective as G67 at both preventing lung tumor growth and prolonging survival in our lung cancer mouse model. We observed a positive correlation between the in vitro p53 function and the in vivo antitumoral activities of liposome-p53 formulations, which had not been reported previously in studies of an intravenous liposome gene delivery system. This correlation may facilitate the development and optimization of a liposome-p53 formulation for aerosol use in lung cancer patients.

Effective treatment of early endobronchial cancer with regional administration of liposome-p53 complexes

BACKGROUND

Lung cancer originates in a diffusely damaged bronchial epithelium as a result of sequential and cumulative genetic alterations. We investigated the feasibility of in vivo gene replacement in endobronchial precancerous and cancerous cells by a regionally administered nonviral delivery system.

METHODS

After evaluating the in vitro transfection efficiency and cytotoxicity of a variety of cationic liposome-p53 formulations, a specific formulation, DP3-p53, was selected for further in vitro and in vivo evaluation. The ability of DP3-p53 to introduce the p53 gene in the normal bronchial epithelium was studied in transgenic mice that lack the p53 gene. The therapeutic effect of DP3-p53 administered intratracheally was studied in two nude mouse models of endobronchial human lung cancer by use of H358 (p53-null) and H322 (p53-mutant) cells.

RESULTS

DP3-p53 was able to effectively introduce and express the p53 gene and induce G1 arrest and apoptosis in H358 cells in vitro and to introduce and transcribe the p53 gene in the bronchial epithelium of transgenic mice that lack the p53 gene in vivo. In therapeutic experiments using groups of four or five mice each, administration of five intratracheal doses of DP3-p53 (2 microg or 8 microg DNA per dose) on days 4, 8, 12, 16, and 20 after intratracheal tumor inoculation significantly inhibited lung tumor formation and prolonged by approximately twofold the survival of mice bearing H358 or H322 endobronchial tumor cells in contrast to the survival among untreated mice and mice treated with the DP3-empty vector (P = .007 [two-sided logrank test] for mice bearing H358 cells and P = .008 [two-sided logrank test] for those bearing H322 cells).

CONCLUSIONS/IMPLICATIONS

Liposome-based p53 delivery through the airways is a potentially effective strategy for the treatment of early endobronchial cancer. These results have important implications for the gene therapy and prevention of human lung cancer.

[Kidney reinforcing and yang supporting action of cistanche deserticola Y. C. Ma before and after preparation]

The weights of seminal vesicle and prostate gland of castrated young rats were significantly increased by administration of alcoholsoluble extract from decoction of Cistanche deserticola. The weights of testes, seminal vesicle and prostate gland in mice and rats were also increased by the extract. The phagocytic function of intra-abdominal macrophage in mice was activated by decoction of Cistanche deserticola. The results showed no statistical differences between crude and prepared drugs. The maximum oral tolerance for mouse was 40 g/kg.

[Folk medicine of the Qiang nationality]

Based on a two-year investigation of folk medicine of the Qiang Nationality, systematic studies have been made on its formation and development, specific methods of physical therapy and experiences and features of clinical application.

[Comparison between Cistanche deserticola Y. C. Ma and C, tubulosa (Shenk) Wight on some pharmacological actions]

The weights of seminal vesicle and prostate gland of castrated young rats were significantly increased by administration of alcohol soluble extract from the decoction of Cintanche deserticola, C. tubulosa and soaked C. deserticola. The phagocytic function of intra-abdominal macrophage in mice was activated by the decoction of C. deserticola and C. tubulosa.

[Prophylactic effect of systemic ceftazidime on bacterial translocation in scalded rats]

In this study, we evaluated the prophylactic effect of Ceftazidime on bacterial translocation (BT) of Pseudomonas aeruginosa in scalded rat by qualitative and quantitative bacterial cultures of blood, organs and mesenteric lymph nodes (MLN). Ceftazidi-me was administered systemically at 3 h, 6 h and 12 h post injury respectively. The dynamic changes in levels of Ceftazidime in blood and organ tissues were also determined. The results showed that effective levels of Ceftazidime in blood, liver and mucosa of the small intestine were rapidly reached and maintained for more than 4 h, but no drug was found in MLN. The prophylactic effect on BT was significant when systemic administration started at 3 h post injury (P < 0.001) and 6 h post injury (P < 0.05). Although the incidence of BT was unchanged (P > 0.05) when systemic administration started at 12 h, the number of organisms present in livers and kidneys, except MLN, was dramatically reduced (P < 0.01).

[The pharmacokinetics of ceftazidime in the burned patients]

Pharmacokinetic studies were carried out following systemic administration of ceftazidime in ten burn patients (TBSA 30%-60% and with full-thickness burn) and six healthy volunteers. Dynamic ceftazidime concentrations in blood, urine and blister fluid were analysed by HPLC. The results showed that the burned patients, especially during their shock phase, some pharmacokinetics parameters differed from that of normal volunteers, in that the volume of distribution (0.45 +/- 0.06 L/kg vs. 0.23 +/- 0.05 L/kg) and non-renal clearance of drug (30.54 +/- 21.97ml.min-1 vs. 11.08 +/- 4.91 ml.min-1) increased, but the elimination of half-life was prolonged. The result indicated that it was not necessary to increase the dosage of ceftazidime in extensive burns in the early period. Burn blister fluid concentrations were higher than MIC. Ranging from 1.004-21.62 micrograms/ml, indicating that systemic ceftazidime could penetrate second-degree burn tissue in the early postburn stage.