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1.
Background: Archaeological bones contain only small amounts of DNA due to post-mortem DNA degradation and the changes endogenous DNA is subjected to during diagenesis. An important step before undertaking such time-consuming and costly analyses as ancient DNA investigation is to predict the presence of DNA in ancient samples. To date, the leading screening method has been amino acid racemization; however, other analytical techniques can also be used to assess the degree of bone preservation.

Aim: The aim of the present study was to relate the presence of DNA with bone preservation in order to select samples potentially suitable for ancient DNA analysis.

Subjects and methods: Bones collected from several archaeological sites, different locations (cave, rockshelter or sub divo) and diachronic periods were selected for analytical and spectroscopic analysis in order to correlate bone tissue preservation with the presence of DNA. Different techniques were combined to assess the degree of preservation of organic and inorganic components.

Results: As determined by different analytical methods, preservation of the inorganic component was best associated with the presence of DNA.

Conclusion: Evaluation of the bone preservation state may be an efficient step to predict the presence of DNA in ancient samples prior to aDNA analysis.  相似文献   


2.
Background: Tenofovir disoproxil fumarate (TDF) is a component of many combinations of antiretroviral treatment (ART) regimens. Although potent and generally well tolerated, TDF may cause renal and bone toxicity. The magnitude of off-target side effects is proposed to be related to tenofovir plasma concentrations, which are affected by food and drug–drug interactions with concomitant antiretrovirals.

Objective: To perform a systematic literature review and qualitatively report on renal and bone safety outcomes associated with efavirenz (EFV), emtricitabine (FTC), and TDF (EFV+FTC+TDF) ART.

Methods: Embase and PubMed databases were searched for randomized clinical trials and observational cohort studies reporting on HIV treatment with EFV+FTC+TDF. Relevant articles were hand-searched for renal (Grade 3–4 serum creatinine/estimated glomerular filtration rate elevations, renal adverse events [AEs], discontinuation due to renal AEs, and urinary biomarkers) and bone outcomes (bone mineral density [BMD] reductions, bone turnover markers, and fracture), and results compiled qualitatively.

Results: Of 337 retrieved articles, 29 reporting renal and 11 reporting bone outcomes met the review criteria. EFV+FTC+TDF was associated with a low frequency of renal AEs and treatment discontinuations due to renal AEs. Renal AEs were more frequent when TDF was taken with protease inhibitor (PI)- or cobicistat-containing ART. EFV+FTC+TDF was associated with reduced BMD and increased bone turnover markers, but BMD reductions were less than with PI-containing ART. No treatment-related bone fractures were identified.

Conclusions: EFV+FTC+TDF appeared to have a more favorable renal safety profile than TDF administered with a PI or cobicistat. BMD decreased with EFV+FTC+TDF, but no treatment-related fractures were identified.  相似文献   


3.
Background: Osteoporosis is characterized by low bone mineral density (BMD), which is determined by an interaction of genetic, metabolic and environmental factors.

Aim: To analyse the association between two polymorphisms of VDR as well as their haplotypes with BMD in post-menopausal Maya-Mestizo women.

Subjects and methods: This study comprised 600 post-menopausal Maya-Mestizo women. A structured questionnaire for risk factors was applied and BMD was assessed at the lumbar spine (LS) and total hip (TH) by dual-energy X-ray absorptiometry. DNA was extracted from blood leukocytes. Two single-nucleotide polymorphisms of VDR (rs731236 and rs2228570) were studied using real-time PCR allelic discrimination for genotyping. Differences between the means of the BMDs according to the genotype were analysed with covariance. Haplotype analysis was conducted.

Results: TT genotype of rs731236 of VDR had higher BMD at total hip and femoral neck (FN), and one haplotype formed by the two polymorphisms was associated with only TH-BMD variations. This difference was statistically significant after adjustment for confounders. The genotype of rs2228570 of VDR analysis showed no significant differences with BMD variations.

Conclusion: The results showed that the TT genotype of rs731236 of VDR and one haplotype formed by rs731236 and rs2228570 polymorphisms were associated with higher BMD at TH and FN.  相似文献   


4.
Background: The applicability of the Gilsanz-Ratib (GR) digital atlas to bone age (BA) determination in China has not been evaluated.

Aim: To compare the validity of GR and the Greulich-Pyle (GP) atlas in BA determination for children in Shanghai.

Subjects and methods: Left-hand radiographs of 243 girls and 375 boys aged 0–13 years were obtained for suspected trauma. They were divided into eight sub-groups according to gender and age (0–3, 3–7, 7–10 and 10–13 years). Radiographs were read by two radiologists, using both GP and GR atlases. The differences between BA and calendar age (CA) were analysed. The inter- and intra-observer consistency was evaluated.

Results: Pearson’s correlation coefficients indicated a strong positive correlation between methods and between raters. The differences between BA and CA of two sub-groups (10–13-year-old boys, GR; 0–3-year-old girls, GP) were not only statistically significant, but exceeded 1 SD, suggesting biological significance.

Conclusion: Both atlases can be used on most age groups. However, the GR atlas is not recommended in boys aged 10–13 years, while the GP atlas is not suitable for girls aged 0–3 years. Therefore, the use of the GP or GR atlas is practical, depending on the age of the child.  相似文献   


5.
6.
Background: Harpagoside (HAR) is an active component of Scrophularia ningpoensis (SN), which has anti-inflammatory and anti-immune effects. SN is used widely in China to treat various diseases. Recently, SN has been used as a traditional Chinese medicine injection and used clinically. However, allergic responses to these injections are frequently reported.

Aim: We examined whether the main component of SN, HAR, is associated with the allergic reaction to SN.

Methods: This study assessed the effects of HAR in mice and mast cell activation to characterize its anaphylactic effects and underlying mechanisms. Mice hindpaw swelling, serum allergy factor detection, enzyme-linked immunosorbent assays, and degranulation assays were performed to measure allergic mediators both in vivo and in vitro.

Results: The present study indicated that HAR induced paw swelling, interleukin-6, inositol triphosphate, tumor necrosis factor-α, and histamine increases in mice. Our in vitro data also showed that HAR induced β-hexosaminidase, inositol triphosphate, and interleukin-6 release, leading to mast cell degranulation. In contrast, neither C48/80 nor HAR induced local anaphylaxis in STOCK KitW-sh/HNihrJaeBsmJNju mice.

Conclusions: HAR is a potential sensitization compound in SN, and these results provide information for the safe clinical use of SN.  相似文献   


7.
Background: Clinical studies have reported a significant association between matrix metalloproteinases (MMP), particularly (MMP-9), and inflammatory diseases including Behçet’s disease (BD).

Purpose: To study the relationship between MMP-9 rs17576 gene polymorphism and the development of BD, and its relation to disease activity among Egyptian patients.

Methods: A total of 100 BD patients and 100 healthy control volunteers were genotyped for MMP-9 rs17576 polymorphism with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), followed by the confirmation of our results in random subgroups using direct DNA sequencing technique.

Results: The frequency of the GG genotype and G allele was significantly higher in BD patients as compared to the normal controls (p = 0.011, OR 8.61; p = 0.03, OR 1.65, respectively). There was no significant association between the MMP-9 rs17576 polymorphism and the clinical outcomes of BD.

Conclusion: our study suggests a significant association of the MMP-9 rs17576 A/G polymorphism with increased risk of BD development in Egyptian patients.  相似文献   


8.
Purpose: Non-pathological child cortical bone (NPCCB) studies can provide clinicians with vital information and insights. However, assessing the anisotropic elastic properties of NPCCB remains a challenge for the biomechanical engineering community. For the first time, this paper provides elastic moduli values for NPCCB specimens in two perpendicular directions (longitudinal and transverse) and for two different structural components of bone tissue (osteon and interstitial lamellae).

Materials and Methods: Microindentation is one of the reference methods used to measure bone stiffness. Here, 8 adult femurs (mean age 82 ± 8.9 years), 3 child femurs (mean age 13.3 ± 2.1 years), and 16 child fibulae (mean age 10.2 ± 3.9 years) were used to assess the elastic moduli of adult and child bones by microindentation.

Results: For adult specimens, the mean moduli measured in this study are 18.1 (2.6) GPa for osteons, 21.3 (2.3) GPa for interstitial lamellae, and 13.8 (1.7) GPa in the transverse direction.

For child femur specimens, the mean modulus is 14.1 (0.8) GPa for osteons, lower than that for interstitial lamellae: 15.5 (1.5) GPa. The mean modulus is 11.8 (0.7) GPa in the transverse direction. Child fibula specimens show a higher elastic modulus for interstitial lamellae 15.8 (1.5) than for osteons 13.5 (1.6), with 10.2 (1) GPa in the transverse direction.

Conclusion: For the first time, NPCCB elastic modulus values are provided in longitudinal and transverse directions at the microscale level.  相似文献   


9.
Background: The origin of Western African pastoralism, represented today by the Fulani nomads, has been a highly debated issue for the past decades, and has not yet been conclusively resolved.

Aim: This study focused on Alu polymorphisms in sedentary and nomadic populations across the African Sahel to investigate patterns of diversity that can complement the existing results and contribute to resolving issues concerning the origin of West African pastoralism.

Subjects and methods: A new dataset of 21 Alu biallelic markers covering a substantial part of the African Sahel has been analysed jointly with several published North African populations.

Results: Interestingly, with regard to Alu variation, the relationship of Fulani pastoralists to North Africans is not as evident as was earlier revealed by studies of uniparental loci such as mtDNA and NRY. Alu insertions point rather to an affinity of Fulani pastoralists to Eastern Africans also leading a pastoral lifestyle.

Conclusions: It is suggested that contemporary Fulani pastoralists might be descendants of an ancestral Eastern African population that, while crossing the Sahara in the Holocene, admixed slightly with a population of Eurasian (as evidenced by uniparental polymorphisms) ancestry. It seems that, in the Fulani pastoralists, Alu elements reflect more ancient genetic relationships than do uniparental genetic systems.  相似文献   


10.
Objectives: This article seeks to identify neuroanatomical differences in ADHD through an overview of systematic reviews that report encephalic differences compared to a control group in volume, area, activation likelihood or chemical composition.

Methods: We conducted a systematic search using Cochrane guidelines and PRISMA criteria in PubMed, Scopus, Web of Science, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects.

Results: Results revealed broad encephalic involvement that includes a functional frontal and cingulate hypoactivation and structural differences in corpus callosum, cerebellum and basal nuclei.

Conclusions: ADHD symptoms might be due to a multi-network unbalanced functioning hypothesis.  相似文献   


11.
Introduction: An impairment of visually perceiving backward masked stimuli is commonly observed in patients with schizophrenia, yet it is unclear whether this impairment is the result of a deficiency in first or higher order processing and for which subtypes of schizophrenia it is present.

Methods: Here, we compare identification (first order) and metacognitive (higher order) performance in a visual masking paradigm between a highly homogenous group of young first-episode patients diagnosed with paranoid schizophrenia (N?=?11) to that of carefully matched healthy controls (N?=?13).

Results: We find no difference across groups in first-order performance, but find a difference in metacognitive performance, particularly for stimuli with relatively high visibility.

Conclusions: These results indicate that the masking deficit is present in first-episode patients with paranoid schizophrenia, but that it is primarily an impairment of metacognition.  相似文献   


12.
13.
Background: Ethnic differences in the timing of human tooth development are unclear.

Aim: To describe similarities and differences in the timing of tooth formation in two groups of Sudanese children and young adults.

Subjects and methods: The sample consisted of healthy individuals from Khartoum, Sudan, aged 2–23 years. The Northern group was of Arab origin (848 males, 802 females) and the Western group was of African origin (846 males, 402 females). Each mandibular left permanent tooth from first incisor to third molar was assessed from dental radiographs into one of 15 development stages. Mean ages at entry for 306 tooth stages were calculated using probit regression in males/females in each group and compared using a t-test.

Results: Mean ages were not significantly different in most tooth stage comparisons between ethnic groups for both males (61/75) and females (56/76), despite a tendency of earlier mean ages in the Western group. Mean ages for most tooth stage comparisons between males and females (137/155) were not significantly different within ethnic groups suggesting low sexual dimorphism.

Conclusion: The mean ages of most mandibular tooth formation stages were generally not significantly different between ethnic groups or between males and females in this study.  相似文献   


14.
15.
Background: Proteinuria is an uncommon clinical manifestation of IgA nephropathy and is usually seen in cases with severe lesions like endocapillary proliferation. However, it is occasionally seen even with cases with mild glomerular manifestations and may even be of nephrotic range.

Predictor: Podocyte foot process effacement.

Outcome: Severity of proteinuria.

Measurements: Podocyte foot process effacement was measured. Morphometric analysis was performed on transmission electron microscope images using a computerized digital photomicrograph system (BioWizard 4.2 Image analysis software, New Delhi, India). Proteinuria was measured quantitatively assigned into five grades.

Results: It was found that as the extent of proteinuria increased, the effacement ratio also increased, and this was most significant between “no” proteinuria and the rest of the categories.

Conclusion: Nephrotic presentation in IgA nephropathy is a known phenomenon and in certain cases may show near normal glomerular morphology with severe foot process effacement on EM being the only significant finding to explain the proteinuria. Proteinuria in these cases shows a significant correlation with degree of foot process effacement. Renal biopsy is important in these cases because they are known to have a better prognosis and are usually steroid responsive.  相似文献   


16.
Background: The study concerns the comparison of percentile curves of Czech breastfed children with Czech national references from 1991 and 2001 and WHO growth standards. Growth charts of breastfed children demonstrate different curve shapes, especially in the first months of life. Incorrect interpretation of the growth curve could lead to premature introduction of complementary foods or infant formula.

Aim: The comparison of four body parameters of Czech breastfed children with currently used Czech national references and WHO standards in order to recommend that Czech paediatricians use either Czech references or WHO standards in their practice.

Subjects and methods: Nine hundred and sixty breastfed children were included in the study of length-for-age, head circumference-for-age, weight-for-age and weight-for-length parameters. All percentile curves were compared. Values of the 50th percentile expressed in z-scores based on both Czech references and WHO standards were tested.

Results: The study confirmed results of previous surveys documenting that growth of breastfed children is specific. Nevertheless, percentile curves of growth parameters of Czech breastfed children are closer to Czech references than WHO standards.

Conclusions: The Czech national references fulfil the needs of Czech paediatricians (with pointing to specifics of breastfed child growth) and WHO standards are suitable, especially for international comparison.  相似文献   


17.
Purpose: The aim of this study was evaluate the effect of HBO on diabetic rats.

Materials and Methods: Twenty rats were distributed into four groups (= 5): Control (C); Control + HBO (CH); Diabetes (D) and Diabetes + HBO (DH). Diabetes was induced by streptozotocin, and bone defects were created in both femurs in all animals. HBO therapy began immediately after surgery and was performed daily in the CH and DH groups. After 7 days, the animals were euthanized. The femurs were removed, demineralized, embedded in paraffin, and histologic images were analyzed.

Results: Qualitative histologic analyses showed more advanced stage bone regeneration in control groups (C and CH) compared with diabetic groups (D and DH). Histomorphometric analysis showed significantly increased bone neoformation in CH compared with the other groups (< 0.001). Diabetic Group (D) showed decreased bone neoformation compared with non-diabetic groups (C and CH) (< 0.001); however DH did not differ from C Group (> 0.05). The mast cell population increased in CH compared with the other groups (C, D, and DH) (< 0.05). The mast cell population did not differ between D and DH Groups.

Conclusions: This study showed that HBO therapy improved early bone regeneration in diabetic rats and increased the mast cell population only in non-diabetic animals. HBO was shown to be important treatment for minimizing deleterious effects of diabetes on bone regeneration.  相似文献   


18.
Objective: The purpose of this study was to investigate the contribution of executive functions (EF) components and episodic and working memory variables, as well as clinical and demographic factors, to awareness of cognitive ability in traumatic brain injury (TBI).

Methods: Sixty-five TBI patients (mild: n?=?26; moderate/severe: n?=?39) took part in the study. Independent stepwise regression models were calculated for EF and memory predictors, with awareness being measured by patient/informant discrepancy in the Patient Competency Rating Scale.

Results: Models with EF variables indicated that semantic verbal fluency and age are the best predictors of awareness, whereas models including mnemonic functions suggested verbal delayed episodic recall and TBI severity as predictors.

Conclusions: These results are discussed in relation to clinical implications, such as the need to focus efforts of rehabilitation in the cognitive abilities related to awareness, and theoretical models.  相似文献   


19.
Background: The study of past infectious diseases increases knowledge of the presence, impact and spread of pathogens within ancient populations.

Aim: Polymerase chain reaction (PCR) was used to examine bones for the presence of Mycobacterium leprae ancient DNA (aDNA) as, even when leprosy is present, bony changes are not always pathognomonic of the disease. This study also examined the demographic profile of this population and compared it with two other populations to investigate any changes in mortality trends between different infectious diseases and between the pre-antibiotic and antibiotic eras.

Subjects and methods: The individuals were from a site in Central Italy (6th–8th CE) and were examined for the presence of Mycobacterium leprae aDNA. In addition, an abridged life mortality table was constructed.

Results: Two individuals had typical leprosy palaeopathology, and one was positive for Mycobacterium leprae aDNA. However, the demographic profile shows a mortality curve similar to that of the standard, in contrast to a population that had been subjected to bubonic plague.

Conclusions: This study shows that, in the historical population with leprosy, the risk factors for health seem to be constant and distributed across all age classes, similar to what is found today in the antibiotic era. There were no peaks of mortality equivalent to those found in fatal diseases such as the plague, probably due to the long clinical course of leprosy.  相似文献   


20.
Background: Studies concerning child and adolescent growth, development, performance and health aimed at the multiple interactions amongst this complex set of variables are not common in the Portuguese speaking countries.

Aim: The aim of this paper is to address the key ideas, methodology and design of the Oporto Growth, Health and Performance Study (OGHPS).

Subjects and methods: The OGHPS is a multidisciplinary mixed-longitudinal study whose main purpose is to examine the multiple interactions among biological, environmental and lifestyle indicators that affect growth, development, health and performance of Portuguese adolescents aged 10–18 years old.

Results: This study briefly presents baseline results for growth, physical fitness and lifestyle behaviours for those participating in the cross-sectional sample (n ≈ 8000). Approximately 30% were over-fat or obese. On average, boys were more physically fit and active than girls. Few adolescents meet the guidelines for sleep duration (≈10%) and eating habits (16.2–24.8%), while 76–85% meet the recommended levels of moderate-to-vigorous physical activity.

Conclusions: The OGHPS has an innovative approach due to its mixed-longitudinal design and the broad array of variables. Furthermore, subsequent analyses of the longitudinal data will enable a detailed exploration of important factors affecting the growth trajectories of health and performance variables and will also help to identify some of the most opportune times for interventions in terms of health behaviours.  相似文献   


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