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1.
BJOG ; 127(2): 129-137, 2020 01.
Article in English | MEDLINE | ID: mdl-31325209

ABSTRACT

The hologenome concept of evolution is discussed, with special emphasis placed upon the microbiome of women. The microbiome is dynamic, changing under different conditions, and differs between women and men. Genetic variation occurs not only in the host, but also in the microbiome by the acquisition of novel microbes, the amplification of specific microbes, and horizontal gene transfer. The majority of unique genes in human holobionts are found in microbiomes, and mothers are responsible for transferring most of these to their offspring during birth, breastfeeding, and physical contact. Thus, mothers are likely to be the primary providers of the majority of genetic information to offspring via mitochondria and the microbiome. TWEETABLE ABSTRACT: Microbiomes differ between women and men. Most genes in humans are in the microbiome. Mothers transfer most of these genes to offspring.


Subject(s)
Adaptation, Biological/physiology , Adaptation, Physiological/physiology , Gene Transfer, Horizontal/genetics , Host Microbial Interactions/physiology , Microbiota/physiology , Mothers , Adaptation, Biological/genetics , Adaptation, Physiological/genetics , Adult , Animals , Biological Evolution , Evolution, Molecular , Female , Genetic Speciation , Genetic Variation , Heredity , Humans , Male , Microbiota/genetics , Plants , Pregnancy
2.
Phys Chem Chem Phys ; 21(19): 9924-9934, 2019 May 15.
Article in English | MEDLINE | ID: mdl-31038518

ABSTRACT

Structural interpretation of the 31P NMR shifts measured in O,O-diethyl thiophosphate (PT), 5,5-dimethyl-2-mercapto-1,3,2-dioxaphosphorinane 2-oxide (cPT), diethylphosphate (P) and 5,5-dimethyl-2-hydroxy-1,3,2-dioxaphosphinane 2-oxide (cP) was obtained by means of theoretical calculations including the effects of geometry, molecular dynamics, and solvent, relativistic effects and the effect of NMR reference. NMR calculations employed the B3LYP, BP86, BPW91, M06-2X, PBE0, MP2, and HF methods, the Iglo-n (n = II, III), cc-pVnZ (n = D, T, Q, 5), and pcS-n (n = 0, 1, 2, 3, 4) Gaussian-type basis sets and the Slater-type QZ4P atomic basis. Water solvent was described explicitly and/or implicitly. The effects due to molecular dynamics were calculated using molecular dynamics simulations with the GAFF force field and the TIP3P water molecules, and alternatively by means of the zero-point ro-vibrational averaging. Relativistic effects included the spin-orbit calculated within the two-component zero-order relativistic approximation and the effect with the four-component DFT method. Optimal geometries and large-amplitude dynamical motions within the "opened" PT and P molecules contrasted with notably different geometries and confined dynamical motions within the cPT and cP "closed" molecules. These structure-dynamical differences together with the different chemical structures of thiophosphate and phosphate due to a non-esterified sulphur or oxygen atom within the group considerably affected the magnitudes of 31P NMR shifts. The theoretical calculations enabled accurate and reliable structure-dynamical interpretation of the measured 31P NMR shifts. The effects due to explicit solvent and relativity turned out to be indispensable for obtaining accurate 31P NMR shifts particularly in the thiophosphates. Replacement of the non-esterified oxygen atom in the phosphate with sulphur makes NMR shielding of the phosphorus atom qualitatively different as compared to the NMR shielding of the phosphorus atom in phosphate, H3PO4 and PH3.

3.
J Prev Alzheimers Dis ; 4(3): 174-182, 2017.
Article in English | MEDLINE | ID: mdl-29182708

ABSTRACT

BACKGROUND: Objectives: Elevated plasma total homocysteine (tHcy) is associated with increased risk of cardiovascular disease, stroke and dementia. Results of clinical trials using B-vitamins to reduce the cognitive risks attributed to tHcy have been inconsistent. The high prevalence of both hyperhomocysteinemia and cognitive impairment among kidney transplant recipients makes them an important population in which to evaluate the effect of lowering homocysteine on cognitive function. We therefore evaluated whether B-vitamin therapy to lower tHcy would prevent cognitive-decline in a cohort of stable kidney transplant recipients. DESIGN: The study was a longitudinal ancillary of the FAVORIT trial, a randomized, placebo-controlled multi-site trial of high-dose B vitamins to reduce cardiovascular and cerebrovascular events in clinically stable kidney transplant recipients with elevated tHcy. PARTICIPANTS: 584 participants from 18 sites across North America. INTERVENTION: The intervention consisted of a daily multivitamin containing high-doses of folate (5.0 mg), vitamin B12 (1.0 mg) and vitamin B6 (50 mg). The placebo consisted of a daily multi-vitamin containing no folate and recommended daily allowances of vitamins B12 and B6 (0 mg folate; 2.0 µg vitamin B12; 1.4 mg vitamin B6). MEASUREMENTS: Annual neuropsychological assessment for up to 5 years (mean 3.3 years) using a standardized test battery. Efficacy was analyzed on an intention-to-treat basis using end-of-trial data. Subgroup analyses included stratification for baseline plasma B-vitamin and tHcy concentrations. RESULTS: At baseline, cognitive impairment was common with 61% of participants falling more than one standard deviation below published norms for at least one cognitive test. Fewer than 1% of participants had insufficient plasma folate < 5 ng/ml or vitamin B12 < 148 pmol/L. However, 44.6% had plasma B6 concentrations < 30 nmol/L. At follow-up, processing speed and memory scores were modestly but significantly better in the B-vitamin supplement group than in controls (p≤0.05). There was no interaction between baseline tHcy, B-vitamin status and treatment on the cognitive outcomes. CONCLUSIONS: High-dose B-vitamin supplementation provided modest cognitive benefit for kidney transplant recipients with elevated baseline tHcy. Since nearly all participants were folate and vitamin B12 sufficient at baseline, the potential cognitive benefits of folate and B12 supplementation in individuals with poor B-vitamin status remains to be determined.


Subject(s)
Cognition Disorders/diet therapy , Dietary Supplements , Hyperhomocysteinemia/diet therapy , Kidney Transplantation , Postoperative Complications/diet therapy , Vitamin B Complex/administration & dosage , Cognition , Cognition Disorders/blood , Cognition Disorders/etiology , Cross-Sectional Studies , Female , Folic Acid/administration & dosage , Folic Acid/blood , Follow-Up Studies , Homocysteine/blood , Humans , Hyperhomocysteinemia/blood , Hyperhomocysteinemia/etiology , Hyperhomocysteinemia/psychology , Longitudinal Studies , Male , Middle Aged , Neuropsychological Tests , North America , Postoperative Complications/blood , Postoperative Complications/psychology , Treatment Outcome , Vitamin B Complex/blood
4.
Phys Med Biol ; 60(11): 4383-98, 2015 Jun 07.
Article in English | MEDLINE | ID: mdl-25985207

ABSTRACT

In this work the dosimetric performance of CMOS active pixel sensors for the measurement of small photon beams is presented. The detector used consisted of an array of 520 × 520 pixels on a 25 µm pitch. Dosimetric parameters measured with this sensor were compared with data collected with an ionization chamber, a film detector and GEANT4 Monte Carlo simulations. The sensor performance for beam profiles measurements was evaluated for field sizes of 0.5 × 0.5 cm(2). The high spatial resolution achieved with this sensor allowed the accurate measurement of profiles, beam penumbrae and field size under lateral electronic disequilibrium. Field size and penumbrae agreed within 5.4% and 2.2% respectively with film measurements. Agreements with ionization chambers better than 1.0% were obtained when measuring tissue-phantom ratios. Output factor measurements were in good agreement with ionization chamber and Monte Carlo simulation. The data obtained from this imaging sensor can be easily analyzed to extract dosimetric information. The results presented in this work are promising for the development and implementation of CMOS active pixel sensors for dosimetry applications.


Subject(s)
Photons , Radiometry/methods , Monte Carlo Method
5.
Phys Med Biol ; 59(23): 7107-23, 2014 Dec 07.
Article in English | MEDLINE | ID: mdl-25365447

ABSTRACT

There is increasing interest in using Cerenkov emissions for quality assurance and in vivo dosimetry in photon and electron therapy. Here, we investigate the production of Cerenkov light during proton therapy and its potential applications in proton therapy. A primary proton beam does not have sufficient energy to generate Cerenkov emissions directly, but we have demonstrated two mechanisms by which such emissions may occur indirectly: (1) a fast component from fast electrons liberated by prompt gamma (99.13%) and neutron (0.87%) emission; and (2) a slow component from the decay of radioactive positron emitters. The fast component is linear with dose and doserate but carries little spatial information; the slow component is non-linear but may be localised. The properties of the two types of emission are explored using Monte Carlo modelling in GEANT4 with some experimental verification. We propose that Cerenkov emissions could contribute to the visual sensation reported by some patients undergoing proton therapy of the eye and we discuss the feasibility of some potential applications of Cerenkov imaging in proton therapy.


Subject(s)
Algorithms , Proton Therapy/standards , Radiometry/methods , Electrons , Humans , Light , Proton Therapy/adverse effects , Proton Therapy/methods , Quality Control
8.
Praxis (Bern 1994) ; 101(18): 1207-12, 2012 Sep 05.
Article in German | MEDLINE | ID: mdl-22945824

ABSTRACT

The correct setting of the ultrasound equipment is a prerequisite for a high quality of the ultrasound examination. Both the B-mode ultrasonography, as well as the Doppler technique offer interesting alternative settings that are often inadequately used. This brief summary of basic settings should help the practicing clinicians in everyday life and motivate them to deal with the «knobs¼ of the ultrasound device. Good practical help will provided by the «Sonocave¼ an event regularly organized at the annual ultrasonic training Congress in Davos, where recognized experts will answer such «Knobology¼-questions and demonstrate the appropriate settings also practically.


Subject(s)
Education, Medical, Continuing , Image Enhancement , Image Processing, Computer-Assisted , Ultrasonography, Doppler, Color/instrumentation , Ultrasonography, Doppler/instrumentation , Ultrasonography/instrumentation , Calibration , Curriculum , Equipment Design , Humans , Image Enhancement/instrumentation , Image Processing, Computer-Assisted/instrumentation , Switzerland
9.
Neurology ; 74(1): 18-26, 2010 Jan 05.
Article in English | MEDLINE | ID: mdl-19940273

ABSTRACT

BACKGROUND: Vitamin D deficiency has potential adverse effects on neurocognitive health and subcortical function. However, no studies have examined the association between vitamin D status, dementia, and cranial MRI indicators of cerebrovascular disease (CVD). METHODS: Cross-sectional investigation of 25-hydroxyvitamin D [25(OH)D], dementia, and MRI measures of CVD in elders receiving home care (aged 65-99 years) from 2003 to 2007. RESULTS: Among 318 participants, the mean age was 73.5 +/- 8.1 years, 231 (72.6%) were women, and 109 (34.3%) were black. 25(OH)D concentrations were deficient (<10 ng/mL) in 14.5% and insufficient (10-20 ng/mL) in 44.3% of participants. There were 76 participants (23.9%) with dementia, 41 of which were classified as probable AD. Mean 25(OH)D concentrations were lower in subjects with dementia (16.8 vs 20.0 ng/mL, p < 0.01). There was a higher prevalence of dementia among participants with 25(OH)D insufficiency (< or =20 ng/mL) (30.5% vs 14.5%, p < 0.01). 25(OH)D deficiency was associated with increased white matter hyperintensity volume (4.9 vs 2.9 mL, p < 0.01), grade (3.0 vs 2.2, p = 0.04), and prevalence of large vessel infarcts (10.1% vs 6.9%, p < 0.01). After adjustment for age, race, sex, body mass index, and education, 25(OH)D insufficiency (< or =20 ng/mL) was associated with more than twice the odds of all-cause dementia (odds ratio [OR] = 2.3, 95% confidence interval [CI] 1.2-4.2), Alzheimer disease (OR = 2.5, 95% CI 1.1-6.1), and stroke (with and without dementia symptoms) (OR = 2.0, 95% CI 1.0-4.0). CONCLUSIONS: Vitamin D insufficiency and deficiency was associated with all-cause dementia, Alzheimer disease, stroke (with and without dementia symptoms), and MRI indicators of cerebrovascular disease. These findings suggest a potential vasculoprotective role of vitamin D.


Subject(s)
Alzheimer Disease/etiology , Dementia/etiology , Stroke/etiology , Vitamin D Deficiency/complications , Vitamin D/analogs & derivatives , Aged , Aged, 80 and over , Body Mass Index , Confidence Intervals , Cross-Sectional Studies , Dementia/classification , Female , Humans , Logistic Models , Magnetic Resonance Imaging/methods , Male , Neurologic Examination/methods , Odds Ratio , Phlebotomy/methods , Retrospective Studies , Risk Factors , Temporal Lobe/pathology , Vitamin D/blood
11.
J Nutr Health Aging ; 11(4): 299-303, 2007.
Article in English | MEDLINE | ID: mdl-17653485

ABSTRACT

OBJECTIVE: Homebound elderly are at increased risk for micronutrient deficiencies and nutritional status in this population has not been adequately described. There is evidence for beneficial effects of multivitamin use and a greater understanding of their nutritional contribution could identify behaviors that may help alleviate excess chronic disease. The purpose of this analysis is to investigate, in a racially diverse group of homebound elders, the association of multivitamin use with measures of plasma B vitamin concentrations. DESIGN: We examined the cross-sectional association between multivitamin use and plasma concentrations of B vitamins and homocysteine in 236 white and 182 black homebound elders (65-99y). Dietary intake was assessed and demographic and health information was ascertained. RESULTS: White and black elders had a high prevalence of dietary intakes below the Estimated Average Requirement for folate (38.1 and 40.7%), vitamin B6 (16.9 and 19.2%.), and vitamin B12 (3 and 3.9%) respectively. Multivitamin use was associated with higher mean plasma B vitamin concentrations in each group. In whites, multivitamin users had higher concentrations of vitamin B6 (64.6 vs. 32.4 nmol/L; p < 0.001), vitamin B12 (398 vs. 324 pmol/L;p < 0.001) and folate (39.4 vs. 30.4 nmol/L;p < 0.001). Black multivitamin users had higher concentrations of vitamin B6 (53.7 vs. 29.5 nmol/L; p < 0.001), B12 (427 vs. 372 pmol/L; p < 0.05) and folate (35.7 vs. 25.4 nmol/L; < 0.001) than non-users. CONCLUSIONS: Multivitamin supplementation was associated with higher mean plasma concentrations of vitamins B6, B12, and folate and lower prevalence of low plasma B vitamin status in a biracial homebound elderly.


Subject(s)
Aging/blood , Homebound Persons/statistics & numerical data , Nutrition Policy , Nutritional Status , Vitamin B Complex/blood , Vitamins/administration & dosage , Black or African American/statistics & numerical data , Aged , Aged, 80 and over , Chronic Disease/prevention & control , Cross-Sectional Studies , Dietary Supplements/statistics & numerical data , Female , Homocysteine/blood , Humans , Male , Surveys and Questionnaires , White People/statistics & numerical data
12.
Int J Oral Maxillofac Surg ; 35(8): 696-703, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16766160

ABSTRACT

One hundred and forty four patients underwent magnetic resonance imaging (MRI) for evaluation of suspected internal derangement (ID) of the temporomandibular joint (TMJ). All scans were performed on a state-of-the-art scanner by highly experienced technologists and evaluated by a single Head and Neck/Maxillofacial radiologist. Seventy-nine percent of patients were female and 21% male. Age distribution of the cases was bi-modal with first peak at 20-30 years of age and second peak at 50-60 years of age. Of the 82.5% of cases with disc displacement, 59.5% demonstrated reduction with opening and 40.5% did not reduce. Anterior disc displacement is common (44%) and sideways displacement rare (4%). Antero-lateral displacement was the second commonest type of displacement (29%) probably related to the weakness of the lateral disc attachment.


Subject(s)
Joint Dislocations/pathology , Magnetic Resonance Imaging , Temporomandibular Joint Disc/pathology , Temporomandibular Joint Disorders/pathology , Adult , Aged , Aged, 80 and over , Female , Humans , Joint Dislocations/epidemiology , Magnetic Resonance Imaging/methods , Male , Middle Aged , Prevalence , Temporomandibular Joint Disc/injuries , Temporomandibular Joint Disorders/epidemiology
15.
Circulation ; 105(23): 2725-9, 2002 Jun 11.
Article in English | MEDLINE | ID: mdl-12057985

ABSTRACT

BACKGROUND: A causal role for mildly elevated plasma homocysteine (tHcy) in cardiovascular disease remains undetermined. To address the unresolved issue of the antecedent-consequent directionality of the relationship, we assessed the familial association of tHcy with parental myocardial infarction (MI) in young Israeli men and women. We also compared tHcy concentrations in Jerusalem, where rates of coronary heart disease (CHD) are high, with the United States Third National Health and Examination Survey (NHANES III). METHODS AND RESULTS: A total of 8646 17-year-olds and 6952 parents were examined from 1976 to 1979 in Jerusalem. At ages 28 to 32 years, offspring of parents who experienced a documented MI during a 10-year follow-up (n=133 men, 62 women; 72% response) and offspring of CHD-free parents (n=389 men, 208 women; 71% response) were reexamined. tHcy levels were determined by the same laboratory for the NHANES non-Hispanic white population aged 25 to 34 years (n=379) and the Jerusalem population sample (n=858). Men from Jerusalem, but not women, had clearly higher tHcy levels than the sample from the United States (90th percentile, 23 versus 14 micromol/L). This difference was largely attributable to lower plasma vitamin B12 levels in the Israeli population. Male case offspring had higher adjusted tHcy than did controls (1.9 micromol/L, P=0.002). Logistic modeling revealed a graded increase in risk of parental MI across quintiles of offspring tHcy, with an adjusted odds ratio of 2.7 in the 5th quintile (P=0.0026 for trend). CONCLUSIONS: The higher tHcy in young male offspring of parents with CHD suggests that elevated tHcy precedes manifestation of CHD. The elevated population tHcy in men may contribute to the high incidence of CHD in Israel.


Subject(s)
Homocysteine/blood , Myocardial Infarction/etiology , Adolescent , Adult , Case-Control Studies , Cholesterol/blood , Coronary Disease/epidemiology , Coronary Disease/etiology , Family Health , Female , Follow-Up Studies , Humans , Incidence , Israel/epidemiology , Male , Myocardial Infarction/blood , Myocardial Infarction/epidemiology , Risk Factors , United States
16.
J Nutr ; 131(12): 3277-80, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11739880

ABSTRACT

In 1996 the Food and Drug Administration (FDA) issued a regulation to take effect in January 1998 that all enriched cereal grain products include 140 microg of folic acid/100 g. The present cross-sectional study was undertaken to assess the effect of this fortification on RBC folate concentrations in the Framingham Offspring Cohort. Among those who did not take B-vitamin supplements, we compared RBC folate in 561 individuals who were examined before implementation of the FDA mandatory folic acid fortification (not exposed) vs. 354 individuals who were examined after implementation of fortification (exposed). We calculated the prevalence of deficient (<160 microg/L, 362.6 nmol/L) and acceptable (>200 microg/L, 453.2 nmol/L) RBC folate concentrations in both groups. Those exposed to folic acid fortification had a mean RBC folate of 450.0 microg/L (1019.7 nmol/L), a value 38% higher than the mean RBC folate of 325.3 microg/L (737.1 nmol/L) in those who were not exposed to fortification (P < 0.001). The prevalence of individuals with deficient RBC folate was 4.9% in the group not exposed to fortification compared with 1.9% in the group exposed to fortification (P < 0.02), and the prevalence of individuals with acceptable RBC folate was 87.0% in the group not exposed to fortification compared with 96.1% in the group exposed to fortification (P < 0.001). Similar results were seen in individuals who used supplements containing B-vitamins. The results of this study showed that in this cohort, the introduction of folic acid fortification significantly improved folate nutritional status measured as RBC folate.


Subject(s)
Erythrocytes/chemistry , Folic Acid/administration & dosage , Folic Acid/blood , Food, Fortified , Adult , Aged , Aged, 80 and over , Cohort Studies , Cross-Sectional Studies , Dietary Supplements , Edible Grain , Female , Heart Diseases , Humans , Male , Massachusetts , Middle Aged , Nutritional Status
17.
Nucleosides Nucleotides Nucleic Acids ; 20(8): 1497-522, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11554542

ABSTRACT

A series of novel, unusual type of acyclic phosphonate-based nucleotide analogues related to well-known antivirals (PMEA and HPMPA) was synthesized using easily available synthon. These compounds, which are distinguished for the presence of phosphonomethyl acetal linkage, form a group of derivatives that contribute to the understanding of structure-activity relationship within the area of acyclic nucleotide analogues.


Subject(s)
Hydrocarbons, Acyclic/chemical synthesis , Hydrocarbons, Acyclic/pharmacology , Purines/chemical synthesis , Purines/pharmacology , Pyrimidines/chemical synthesis , Pyrimidines/pharmacology , Anticarcinogenic Agents/chemical synthesis , Anticarcinogenic Agents/chemistry , Anticarcinogenic Agents/pharmacology , Cell Line , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , DNA Viruses/drug effects , HeLa Cells , Humans , Hydrocarbons, Acyclic/chemistry , Magnetic Resonance Spectroscopy , Mass Spectrometry , Purines/chemistry , Pyrimidines/chemistry , Retroviridae/drug effects , Spectrophotometry, Ultraviolet , Structure-Activity Relationship
18.
Article in English | MEDLINE | ID: mdl-11563123

ABSTRACT

Several types of isopolar modified oligothymidylates and oligoadenylates (15 mers) with the phosphonate -O-P-CH2-O- internucleotide linkage were prepared. The modified oligonucleotides were subjected to the study of their hybridization properties, resistance against nucleases, and the ability to elicit RNase H activity.


Subject(s)
Oligonucleotides, Antisense/chemical synthesis , Organophosphonates/chemistry , Adenosine Monophosphate/chemistry , Cross-Linking Reagents/chemistry , Nucleic Acid Hybridization , Oligonucleotides, Antisense/chemistry , Oligonucleotides, Antisense/metabolism , Ribonuclease H/metabolism , Thymidine Monophosphate/chemistry
19.
J Immunol ; 167(7): 3887-93, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11564806

ABSTRACT

Mucosal damage induces a massive influx of serum complement components into the lumen. The epithelium produces a number of factors that can potentially ameliorate injury including intestinal trefoil factor (ITF), a small protease-resistant peptide produced and secreted onto the mucosal surface by goblet cells, and decay-accelerating factor (DAF), a protein produced by columnar epithelium which protects the host tissue from autologous complement injury. However, coordination of these intrinsic defensive products has not been delineated. DAF protein and mRNA expression were evaluated by immunoblotting and Northern blotting, respectively. NF-kappaB-DNA binding activity and DAF promoter activity were assessed by an electrophoretic gel mobility shift assay and a reporter gene luciferase assay, respectively. ITF induced a dose- and time-dependent increase in DAF protein and mRNA expression in human (HT-29 and T84) and rat (IEC-6) intestinal epithelial cells. In differentiated T84 cells grown on cell culture inserts, basolateral stimulation with ITF strongly enhanced DAF expression, but apical stimulation had no effects. The C3 deposition induced by complement activation was significantly blocked by the treatment with ITF. In HT-29 cells, ITF increased the stability of DAF mRNA. ITF also enhanced the promoter activity of the DAF gene via NF-kappaB motif and induced activation of NF-kappaB-DNA binding activity. ITF promotes protection of epithelial cells from complement activation via up-regulation of DAF expression, contributing to a robust mucosal defense.


Subject(s)
CD55 Antigens/genetics , Complement Activation , Growth Substances/pharmacology , Immunity, Mucosal , Intestinal Mucosa/immunology , Mucins , Muscle Proteins , Neuropeptides , Peptides/pharmacology , Transcriptional Activation , Animals , CD55 Antigens/biosynthesis , Cell Line , Complement C3/metabolism , Humans , Kinetics , NF-kappa B/metabolism , Promoter Regions, Genetic , Protein Biosynthesis , RNA Stability , RNA, Messenger/metabolism , Rats , Trefoil Factor-2 , Trefoil Factor-3 , Tumor Cells, Cultured
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