Human evolution and osteoporosis-related spinal fractures

The field of evolutionary medicine examines the possibility that some diseases are the result of trade-offs made in human evolution. Spinal fractures are the most common osteoporosis-related fracture in humans, but are not observed in apes, even in cases of severe osteopenia. In humans, the development of osteoporosis is influenced by peak bone mass and strength in early adulthood as well as age-related bone loss. Here, we examine the structural differences in the vertebral bodies (the portion of the vertebra most commonly involved in osteoporosis-related fractures) between humans and apes before age-related bone loss occurs. Vertebrae from young adult humans and chimpanzees, gorillas, orangutans, and gibbons (T8 vertebrae, n = 8–14 per species, male and female, humans: 20–40 years of age) were examined to determine bone strength (using finite element models), bone morphology (external shape), and trabecular microarchitecture (micro-computed tomography). The vertebrae of young adult humans are not as strong as those from apes after accounting for body mass (p<0.01). Human vertebrae are larger in size (volume, cross-sectional area, height) than in apes with a similar body mass. Young adult human vertebrae have significantly lower trabecular bone volume fraction (0.26±0.04 in humans and 0.37±0.07 in apes, mean ± SD, p<0.01) and thinner vertebral shells than apes (after accounting for body mass, p<0.01). Since human vertebrae are more porous and weaker than those in apes in young adulthood (after accounting for bone mass), even modest amounts of age-related bone loss may lead to vertebral fracture in humans, while in apes, larger amounts of bone loss would be required before a vertebral fracture becomes likely. We present arguments that differences in vertebral bone size and shape associated with reduced bone strength in humans is linked to evolutionary adaptations associated with bipedalism.     

Use of proton pump inhibitors and risk of osteoporosis-related fractures

Background

The use of proton pump inhibitors has been associated with an increased risk of hip fracture. We sought to further explore the relation between duration of exposure to proton pump inhibitors and osteoporosis-related fractures.

Methods

We used administrative claims data to identify patients with a fracture of the hip, vertebra or wrist between April 1996 and March 2004. Cases were each matched with 3 controls based on age, sex and comorbidities. We calculated adjusted odds ratios (OR) for the risk of hip fracture and all osteoporosis-related fractures for durations of proton pump inhibitor exposure ranging from 1 or more years to more than 7 years.

Results

We matched 15 792 cases of osteoporosis-related fractures with 47 289 controls. We did not detect a significant association between the overall risk of an osteoportic fracture and the use of proton pump inhibitors for durations of 6 years or less. However, exposure of 7 or more years was associated with increased risk of an osteoporosis-related fracture (adjusted OR 1.92, 95% confidence interval [CI] 1.16–3.18, p = 0.011). We also found an increased risk of hip fracture after 5 or more years of exposure (adjusted OR 1.62, 95% CI 1.02–2.58, p = 0.04), with even higher risk after 7 or more years exposure (adjusted OR 4.55, 95% CI 1.68–12.29, p = 0.002).

Interpretation

Use of proton pump inhibitors for 7 or more years is associated with a significantly increased risk of an osteoporosis-related fracture. There is an increased risk of hip fracture after 5 or more years exposure. Further study is required to determine the clinical importance of this finding and to determine the value of osteoprotective medications for patients with long-term use of proton pump inhibitors.Osteoporosis is a common condition throughout the developed world, affecting up to 16% of women and 7% of men aged 50 years and older.¹ The presence of underlying osteoporosis is a major risk factor for the development of fractures of the hip, proximal femur, spinal vertebra and forearm. In 2000, the estimated number of people with fractures worldwide was 56 million, and about 9 million new osteoporotic fractures occur each year.² In 1993/94, the number of hip fractures in Canada was 23 375.³ This number is predicted to increase to 88 124 by the year 2041, with a parallel increase in the number of days in hospital (465 000 patient-days in 1993/94 to 1.8 million in 2041).³ Moreover, the case-fatality rate for hip fractures can exceed 20%,⁴ and all osteoporosis-related fractures can lead to substantial long-term disability and decreased quality of life.⁵Many risk factors for the development of osteoporosis-related fracture have been identified, including white ethnic background, low body mass index, physical inactivity and female sex.^6–8 There are also a number of medication classes, including corticosteroids and serotonin selective reuptake inhibitors, whose use has been linked to higher rates of osteoporosis.^9–11 Furthermore, any condition or drug that increases the risk of falls and injury also increases the risk of an osteoporosis-related fracture.^12,13One medication class that may affect bone mineral metabolism is proton pump inhibitors. This class of drugs inhibits the production and intragastric secretion of hydrochloric acid, which is believed to be an important mediator of calcium absorption in the small intestine.¹⁴ Recent studies have suggested that the use of proton pump inhibitors for 1 or more years is associated with hip fracture and other osteoporotic fractures; however, there is limited data on additional risk beyond 4 years exposure.^15,16Because proton pump inhibitors are commonly prescribed to control and prevent symptoms of chronic unrelenting conditions, it is likely that many patients will use these medications for more than 4 years. Therefore, we used an adminstrative database to examine the effects of longer durations of proton pump inhibitor use on the development of osteoporosis-related fractures.     

Vitamin D and osteoporosis-related fracture

The age-related decline in mass and quality of bone (osteoporosis) and muscle (sarcopenia) leads to an exponential increased risk for osteoporosis-related fracture with advancing age in older adults. As vitamin D inadequacy plausibly causally contributes to these declines, optimization of vitamin D status might reduce the deterioration of bone and muscle function with age. Putative mechanisms by which vitamin D inadequacy may increase fracture risk include both direct and indirect effects on bone and muscle. However, controversy currently clouds the role(s) of vitamin D in osteoporosis-related fracture, the amount of vitamin D required and the optimal 25-hydroxyvitamin D level. This review provides an overview of current knowledge and suggests a clinical approach to vitamin D status in older adults with, or at risk for, osteoporosis-related fracture. These recommendations are likely to evolve as additional data becomes available.     

Risk factors and physiopathology of candidiasis

Recent epidemiological surveys have demonstrated an important increase in nosocomial infections among which Candida sp. plays an increasingly prominent role. Candida is now involved in about 10% of all septicemia and leads to a very high mortality rate in immunodepressed patients. Clinical studies show that any modification of the host immune status can facilitate the proliferation of endogenous Candida which, according to the importance of the immune deficiency, can provoke diseases ranging from benign localized mucocutaneous candidosis to sometimes lethal systemic invasions. The pathogenic behavior of Candida cells is mainly due to a very high phenotypic biodiversity. Following even very slight environmental modifications, it may change its behavior through the appearance of new or amplified properties such as tube formation, adherence, protease secretion, etc. Together with the impairment of host defenses, these new invasive properties lead to the so-called opportunistic pathogenicity of Candida cells. From a host point of view, after the integrity of surface teguments, the mucosal protection is ensured by the Th1 "cellular" immune response which, through pro-inflammatory cytokine production, boosts the efficacy of the phagocytes (Polymorphonuclear cells and macrophages). Neutrophils are of particular importance as deep seated Candida proliferation is mostly associated with neutropenia. Whatever the pathogenic process, it is mostly due to modifications provoked by increasing medical awareness which makes patients more susceptible to illness. A better knowledge of the precise mechanisms involved and would lead to improved strategies for prevention.     

Risk factors for gastroschisis

The prevalence at birth of gastroschisis, a rare abnormality of the abdominal wall, appears to have increased over the past decade. To characterize risk factors that might explain this increase, birth certificates for Washington State residents were compared for 62 infants born with gastroschisis during the years 1984 to 1987 and 617 randomly selected unaffected infants matched for birth year. After simultaneously adjusting for 14 potential risk factors, 4 factors stood out. Infants born during January, February, or March were at greater risk than infants born in any other months (odds ratio 2.2, 95% confidence interval 1.1, 4.1). Mothers less than 25 years old were at greater risk than mothers 25 years and older, with the highest risk to mothers less than 20 years old (odds ratio 4.1, 95% confidence interval 1.4, 12.0). Women who smoked during pregnancy were at greater risk than women who did not smoke (odds ratio 2.0, 95% confidence interval 1.03, 3.8). Finally, mothers receiving inadequate prenatal care were at greater risk than mothers receiving adequate prenatal care (odds ratio 2.1, 95% confidence interval 0.99, 4.6). Unidentified behavioral and environmental exposures may explain the associations with month of birth, maternal age, and prenatal care. However, smoking during pregnancy is a plausible risk factor that should be examined further as an explanation of the apparently increasing prevalence at birth of gastroschisis in developed nations.     

玉米倒伏成因及预防

概述了玉米倒伏类型及对产量的影响;与玉米倒伏有关的植株特性及影响玉米倒伏的各种环境因素和预防。     

Ethnic difference in osteoporosis-related phenotypes and its potential underlying genetic determination

Osteoporosis is a serious health problem in both Caucasians and Asians. Caucasians and Asians are two distinct major ethnic groups, which may have differential genetic determination underlying complex genetic diseases such as osteoporosis. However, to date, there has been no systematic review focusing on the aspect of ethnic difference in risk to osteoporosis and its potential underlying genetic determination between Asians and Caucasians. Here, we firstly review diverse aspects of osteoporosis-related differences, including the differences of epidemiology of osteoporotic fractures, peak bone mass, bone loss, bone area, bone geometry and drug treatment response between Asians and Caucasians. Then, we provide some potential genetic evidence on the different heritability and inheritance mode of bone phenotypes, the different osteoporosis candidate genes and the differential results in related molecular studies between them, to explain the above osteoporosis-related phenotypic differences. The results suggest that the osteoporosis-related phenotypic differences between Asians and Caucasians may be partially the result of the different ethnic genetic background. The present review may increase our understanding of potential different mechanisms related to ethnicity in pathogenesis of osteoporosis for effective and potentially customized treatments in different major ethnic groups.     

肝炎后肝硬化患者肝癌发生的保护因素与危险因素研究

目的:通过回顾性病例对照研究,探讨多种因素在病毒性肝炎后肝化门静脉高压症患者HCC发生过程中的作用以及脾切除是否抑制了肝癌的发生进程。方法:收集第四军医大学西京医院病案统计室检索2002年1月～2008年12月之间出院诊断为病毒性肝炎后(HBV/HCV)肝硬化门脉高压的病例2300余例,收集所有病例的一般资料,临床及实验室检查数据,影象学检查结果,以及在治疗过程中的脾切除手术史。采用病例对照,按年龄、性别两个指标进行1:1配对,根据研究对象是否合并HCC将其分为合并HCC组(组1),未合并HCC组(组2),采用SPSS17.0进行单因素分析及多因素logistic回归分析。结果:描述性统计结果显示,两组的ALB、AST、TP、ALP、GGT等差异有统计学意义(P<0.05),而PLT、ALT、TBIL等在两组间差异无统计学意义(P>0.05)。将单因素分析有意义的研究因素纳入多因素logistic回归方程得知,AST、ALP、GGT异常升高增加了肝癌发生的危险性,而行脾切除和门奇断流术明显降低了肝癌发生的危险性,仅为无手术患者肝癌发生危险性的57.1%(OR:0.571,95%CI:0.394～0.825)。...     

Risk factors and risk reduction of breast cancer

Because of its increasing incidence, breast cancer is a significant burden for women worldwide. In industrialized countries, breast cancer is the second-leading cause of cancer-related deaths among women, and it is estimated that 1 in every 8 women will develop the disease during her lifetime. Sufficient evidence indicates that a number of genetic, environmental and lifestyle risk exposures during life may play important roles in the etiology of this disease. The purpose of this paper is to review some etiologic factors and underlying mechanisms in relation to breast cancer risk. Based on the published literature, there is sufficient evidence that some established factors are associated with breast cancer risk. Age, early age at menarche, late menopause, height, post-menopausal obesity, family history of breast cancer, ionizing radiation, oral contraceptives, hormonal replacement therapy, mammographic density, some gene mutations and clinical conditions, such as benign breast disease, are associated with an increased risk of breast cancer. The risk decreases with early childbearing, high parity and physical activity, and breastfeeding. Alcohol increases the risk, while caloric restriction may confer protection from breast cancer. Epidemiological evidence for other nutritional factors is insufficient. These results suggest that breast cancer is a multifactorial disease where genetic susceptibility, environment, nutrition and other lifestyle risk factors interact. Better identification of modifiable risk factors and risk reduction of breast cancer may allow implementation of useful strategies for prevention.     

Risk factors for pancreatic cancer

In the United States, the cumulative mortality or lifetime risk of dying from pancreatic cancer is about 1-2%, but although this form of cancer is rare, nearly all patients die from the disease within one to two years. Because of its lethality, pancreatic cancer now ranks fourth as a cause of death from cancer. There are country-specific differences in rates, perhaps explained by differences in life-style factors or diet. African-Americans in the USA have rates that are about 50% higher than Caucasians. Smoking is the major known risk factor for this cancer, explaining 20-30% of all cases. Another 5-10% of causes are caused by germline mutations, with mutations in BRCA2 being the most frequent. Two background diseases increase the risk of pancreatic cancer-pancreatitis, and diabetes. Major challenges presented by this cancer are: 1) determination of the molecular pathways that make this cancer so aggressive; 2) development of new modalities, perhaps based on proteomics, to enhance early detection.     

胰十二指肠切除术后并发症相关因素分析

目的:探讨胰十二指肠切除术(pancreatoduodenectomy,PD)术后并发症及其危险因素。方法:回顾2000年至2009年第四军医大学西京医院258例行胰十二指肠切除术病人临床资料,并通过单因素分析和多因素分析术后并发症危险因素。结果:本组术后并发症发生率为22.1%(57/258)。多见的并发症包括胰漏、胆漏、腹腔感染,出血等。Logistic回归分析显示,与并发症有关的因素包括术前血清总胆红素>171μmol/L、术前血清白蛋白<30g/L,术中出血量>800 ML,年龄>60岁,术前血红蛋白<100g/L。结论:术前血清总胆红素>171μmol/L,术前血清白蛋白<30g/L和术中出血量>800 ML是胰十二指肠切除术术后并发症的高危因素,其次的危险因素为年龄>60岁、术前血红蛋白<100g/L。手术者应掌握好手术时机,加强围手术期处理,从而降低胰十二指肠切除术术后并发症。     

胰十二指肠切除术后并发症相关因素分析

目的：探讨胰十二指肠切除术（pancreatoduodenectomy,PD）术后并发症及其危险因素。方法：回顾2000年至2009年第四军医大学西京医院258例行胰十二指肠切除术病人临床资料,并通过单因素分析和多因素分析术后并发症危险因素。结果：本组术后并发症发生率为22.1%（57/258）。多见的并发症包括胰漏、胆漏、腹腔感染,出血等。Logistic回归分析显示,与并发症有关的因素包括术前血清总胆红素〉171μmol/L、术前血清白蛋白〈30g/L,术中出血量〉800 ML,年龄〉60岁,术前血红蛋白〈100g/L。结论：术前血清总胆红素〉171μmol/L,术前血清白蛋白〈30g/L和术中出血量〉800 ML是胰十二指肠切除术术后并发症的高危因素,其次的危险因素为年龄〉60岁、术前血红蛋白〈100g/L。手术者应掌握好手术时机,加强围手术期处理,从而降低胰十二指肠切除术术后并发症。     

Risk and resiliency factors in posttraumatic stress disorder

BACKGROUND: Not everyone who experiences a trauma develops posttraumatic stress disorder (PTSD). The aim of this study was to determine the risk and resiliency factors for this disorder in a sample of people exposed to trauma. METHOD: Twenty-five people who had developed PTSD following a trauma and 27 people who had not were asked to complete the Posttraumatic Stress Diagnostic Scale, the Coping Inventory for Stressful Situations, and the State-Trait Anxiety Inventory. In addition, they completed a questionnaire to provide information autobiographic and other information. ANALYSIS: Five variables that discriminated significantly between the two groups using chi-square analysis or t-tests were entered into a logistic regression equation as predictors, namely, being female, perceiving a threat to one's life, having a history of sexual abuse, talking to someone about the event, and the "intentionality" of the trauma. RESULTS: Only being female and perceiving a threat to one's life were significant predictors of PTSD. Taking base rates into account, 96.0% of participants with PTSD were correctly classified as having the disorder and 37.0% of participants without PTSD were correctly classified as not having the disorder, for an overall success rate of 65.4% CONCLUSIONS: Because women are more likely than men to develop PTSD, more preventive measures should be directed towards them. The same is true for trauma victims (of both sexes) who feel that their life was in danger     

Domestic violence. Risk factors and outcomes.

Domestic violence is a pervasive and frequently unrecognized cause of injury among women. We reviewed data from standardized interviews with 218 women who presented to an emergency department with injuries due to domestic violence. Victims ranged in age from 16 to 66 years and constituted a wide range of socioeconomic and ethnic backgrounds. Domestic violence often resulted in severe injury; 28% of the women interviewed required admission to hospital for injuries, and 13% required major surgical treatment. The typical presentation was injuries to the face, skull, eyes, extremities, and upper torso. A third of the cases involved a weapon, such as a knife, club, or gun. In all, 10% of the victims were pregnant at the time of abuse, and 10% reported that their children had also been abused by the batterer. Most victims (86%) had suffered at least one previous incident of abuse, and about 40% had previously required medical care for abuse. Victim recognition and referral to appropriate agencies could be improved if primary care physicians were more aware of the prevalence, severity, frequency of occurrence, and typical presentation of domestic violence.     

Risk factors for human disease emergence

A comprehensive literature review identifies 1415 species of infectious organism known to be pathogenic to humans, including 217 viruses and prions, 538 bacteria and rickettsia, 307 fungi, 66 protozoa and 287 helminths. Out of these, 868 (61%) are zoonotic, that is, they can be transmitted between humans and animals, and 175 pathogenic species are associated with diseases considered to be 'emerging'. We test the hypothesis that zoonotic pathogens are more likely to be associated with emerging diseases than non-emerging ones. Out of the emerging pathogens, 132 (75%) are zoonotic, and overall, zoonotic pathogens are twice as likely to be associated with emerging diseases than non-zoonotic pathogens. However, the result varies among taxa, with protozoa and viruses particularly likely to emerge, and helminths particularly unlikely to do so, irrespective of their zoonotic status. No association between transmission route and emergence was found. This study represents the first quantitative analysis identifying risk factors for human disease emergence.     

Risk factors in the epidemiology of dysentery

The general tendency of a decrease in the morbidity rates of dysentery induced by Shigella sonnei and Shigella flexneri (separately) from Monday to the end of the week (Saturday-Sunday) has been revealed, and at the same time the "infection risk" for both kinds of salmonellosis has been found to fall on the last days of the week (Friday-Sunday).