Common crossroads in diabetes management

The prevalence and impact of type 2 diabetes are reaching epidemic proportions in the United States. Data suggest that effective management can reduce the risk for both microvascular and macrovascular complications of diabetes. In treating patients with diabetes, physicians must be prepared not only to tailor the initial treatment to the individual and his or her disease severity but also to advance treatment as necessary and in step with disease progression. The majority of patients with diabetes are not at goal for glycated hemoglobin A1C, fasting plasma glucose, or postprandial plasma glucose levels. Although lifestyle changes based on improved diet and exercise practices are basic elements of therapy at every stage, pharmacologic therapy is usually necessary to achieve and maintain glycemic control. Oral antidiabetic agents may be effective early in the disease but, eventually, they are unable to compensate as the disease progresses. For patients unable to achieve glycemic control on 2 oral agents, current guidelines strongly urge clinicians to consider the initiation of insulin as opposed to adding a third oral agent. Recent research suggests that earlier initiation of insulin is more physiologic and may be more effective in preventing complications of diabetes. Newer, longer-lasting insulin analogs and the use of simplified treatment plans may overcome psychological resistance to insulin on the part of physicians and patients. This article summarizes the risks associated with uncontrolled fasting and postprandial hyperglycemia, briefly reviews the various treatment options currently available for type 2 diabetes, presents case vignettes to illustrate crossroads encountered when advancing treatment, and offers guidance to the osteopathic physician on the selection of appropriate treatments for the management of type 2 diabetes.     

Common mechanism controlling phase and antigenic variation in pathogenic Neisseriae

The expression of the Neisseria gonorrhoeae opacity protein (Op, protein II), a major antigenic determinant of the outer membrane, is subject to frequent phase transitions. At least nine expression loci (opaE) are involved in the production of a large number of serologically distinct Op types. Using opa-specific oligonucleotides as probes in genomic blots, we detect Op-related gene sequences (opr) in N. meninglitidis as well as in N. lactamica. DNA sequence analysis of such opr genes derived from N. meninglitidis reveals distinct regions of homology with gonococcal opa E genes. As shown in the immunoblot, the proteins encoded by ops and opr are serologically related. Like the opa E genes, the 5′-coding sequences of the opr genes include a repetitive sequence composed of pentameric CTCTT units. The number of these coding repeat (CR) units is variable. This finding, together with the observation that all opr genes are constitutively transcribed, regardless of the status of protein production, suggests a translational control mechanism identical to that of the opa genes in gonococci. The related structures and control mechanisms of opa and opr genes imply a general significance of their gene products for the pathogenic character of the investigated Neisseria species.     

Common mechanism controlling phase and antigenic variation in pathogenic neisseriae

The expression of the Neisseria gonorrhoeae opacity protein (Op, protein II), a major antigenic determinant of the outer membrane, is subject to frequent phase transitions. At least nine expression loci (opaE) are involved in the production of a large number of serologically distinct Op types. Using opa-specific oligonucleotides as probes in genomic blots, we detect Op-related gene sequences (opr) in N. meningitidis as well as in N. lactamica. DNA sequence analysis of such opr genes derived from N. meningitidis reveals distinct regions of homology with gonococcal opa E genes. As shown in the immunoblot, the proteins encoded by opa and opr are serologically related. Like the opaE genes, the 5'-coding sequences of the opr genes include a repetitive sequence composed of pentameric CTCTT units. The number of these coding repeat (CR) units is variable. This finding, together with the observation that all opr genes are constitutively transcribed, regardless of the status of protein production, suggests a translational control mechanism identical to that of the opa genes in gonococci. The related structures and control mechanisms of opa and opr genes imply a general significance of their gene products for the pathogenic character of the investigated Neisseria species.     

批改动物学实验报告时常见的几类问题

动物学实验是大学生物系本科、专科二年级学生的专业必修课。实验报告是实验结束后学生完成的作业,内容涉及绘图和说明实验内容、步骤。现就笔者在批改实验报告中发现的问题和克服办法加以讨论。     

Common mental health problems in immigrants and refugees: general approach in primary care

Background:

Recognizing and appropriately treating mental health problems among new immigrants and refugees in primary care poses a challenge because of differences in language and culture and because of specific stressors associated with migration and resettlement. We aimed to identify risk factors and strategies in the approach to mental health assessment and to prevention and treatment of common mental health problems for immigrants in primary care.

Methods:

We searched and compiled literature on prevalence and risk factors for common mental health problems related to migration, the effect of cultural influences on health and illness, and clinical strategies to improve mental health care for immigrants and refugees. Publications were selected on the basis of relevance, use of recent data and quality in consultation with experts in immigrant and refugee mental health.

Results:

The migration trajectory can be divided into three components: premigration, migration and postmigration resettlement. Each phase is associated with specific risks and exposures. The prevalence of specific types of mental health problems is influenced by the nature of the migration experience, in terms of adversity experienced before, during and after resettlement. Specific challenges in migrant mental health include communication difficulties because of language and cultural differences; the effect of cultural shaping of symptoms and illness behaviour on diagnosis, coping and treatment; differences in family structure and process affecting adaptation, acculturation and intergenerational conflict; and aspects of acceptance by the receiving society that affect employment, social status and integration. These issues can be addressed through specific inquiry, the use of trained interpreters and culture brokers, meetings with families, and consultation with community organizations.

Interpretation:

Systematic inquiry into patients’ migration trajectory and subsequent follow-up on culturally appropriate indicators of social, vocational and family functioning over time will allow clinicians to recognize problems in adaptation and undertake mental health promotion, disease prevention or treatment interventions in a timely way.Changing patterns of migration to Canada pose new challenges to the delivery of mental health services in primary care. For the first 100 years of Canada’s existence, most immigrants came from Europe; since the 1960s, there has been a marked shift, with greater immigration from Asia, Africa, and Central and South America.¹ The mix differs across the provinces, although nearly all immigrants settle in Canada’s largest cities.² The task of preventing, recognizing and appropriately treating common mental health problems in primary care is complicated for immigrants and refugees because of differences in language, culture, patterns of seeking help and ways of coping.^3–6In consultation with experts in immigrant and refugee mental health, we reviewed the literature to determine associated risks and clinical considerations for primary care practitioners in the approach to common mental health problems among new immigrant or refugee patients.^7–10 In this paper, we review the effect of migration on mental health, use of health care and barriers to care. We outline basic clinical strategies for primary mental health care of migrants including the use of interpreters, family interaction and assessment, and working with community resources.     

Interpreting phenotypic variation in plant allelochemistry: problems with the use of concentrations

Ecologists often use concentrations of defensive compounds as measures of plant allocation to defence and/or allelochemical production. I demonstrate that this practice may lead to erroneous conclusions because plants produce and allocate molecules (quantities) of compounds whereas concentrations reflect the distribution of these quantities in plant tissues and are, therefore, functions of plant biomass. As a tool for distinguishing between shifts in allelochemical production versus changes in plant biomass in determining allelochemical concentrations, I suggest using a technique known as graphical vector analysis (GVA) which has been developed for diagnosing nutrient limitations in forest stands, but has seldom been applied by researchers studying plant allelochemicals. I used data from several published studies to demonstrate how GVA can be applied to interpret ontogenetic and environmental effects on allelochemical levels and to compare the results obtained for different allelochemical types, plant species, treatments and experiments. These examples show that changes in plant biomass per se are an important source of variation in allelochemical concentrations and, therefore, concentration data can be easily misinterpreted if changes in absolute content and plant biomass are not considered simultaneously. Because studies reporting variation in allelochemical concentrations have been considered as tests for general theories of plant chemical defence, evidence in support of or against these theories should be re-examined using multivariate techniques such as analysis of covariance, allometric analysis and GVA. Received: 16 September 1998 / Accepted: 4 March 1999     

Male management: Coping with aggression problems in male laboratory mice

In a laboratory environment, aggressive interactions between male mice may exceed normal levels leading to negative effects both on the well-being of the animals and on the validity of experimental results. In this paper we review results from the literature and our own research with regard to coping with excessive aggressive behaviour in male laboratory mice. Based on this review practical recommendations concerning the housing and care of male laboratory mice are formulated. In short, it is recommended to avoid individual housing, to transfer odour cues from the nesting area during cage cleaning and to apply nesting material as environmental enrichment. Furthermore, group size should be optimized to three animals per cage. Further research, in particular into the effects of frequency, duration, type and severity of disturbances during an experiment on the degree of aggression, is recommended.     

Nitrogen in the environment: sources,problems, and management

Nitrogen (N) is applied worldwide to produce food. It is in the atmosphere, soil, and water and is essential to all life. N for agriculture includes fertilizer, biologically fixed, manure, recycled crop residue, and soil-mineralized N. Presently, fertilizer N is a major source of N, and animal manure N is inefficiently used. Potential environmental impacts of N excreted by humans are increasing rapidly with increasing world populations. Where needed, N must be efficiently used because N can be transported immense distances and transformed into soluble and/or gaseous forms that pollute water resources and cause greenhouse effects. Unfortunately, increased amounts of gaseous N enter the environment as N2O to cause greenhouse warming and as NH3 to shift ecological balances of natural ecosystems. Large amounts of N are displaced with eroding sediments in surface waters. Soluble N in runoff or leachate water enters streams, rivers, and groundwater. High-nitrate drinking water can cause methemoglobinemia, while nitrosamines are associated with various human cancers. We describe the benefits, but also how N in the wrong form or place results in harmful effects on humans and animals, as well as to ecological and environmental systems.     

Common variation in KLKB1 and essential hypertension risk: tagging-SNP haplotype analysis in a case-control study

The human plasma kallikrein gene (KLKB1) encodes plasma kallikrein, a serine protease that catalyzes the release of kinins and other vasoactive peptides and may be involved in the pathogenesis of hypertension. In this study, we performed a haplotype-based study to assess the effect of common genetic variation in the KLKB1 gene on the risk of essential hypertension. Eight common single nucleotide polymorphisms (SNPs) were selected from the HapMap database and used to determine the pattern of linkage disequilibrium (LD) and haplotype structure within the KLKB1 gene. Four tag SNPs were then identified with over 85% power to predict both common haplotypes and remaining common SNPs, and genotyped in 1,317 cases with essential hypertension and 1,269 healthy controls. Single SNP analyses indicated that SNPs rs2304595 and rs4253325 were significantly associated with hypertension, adjusted for covariates. Compared with the most common Hap2 CAGC, Hap1 AGAC and Hap3 CGAC, which carry the susceptible rs2304595 G allele and rs4253325 A allele, were found to significantly increase the risk of essential hypertension with adjusted odds ratios equal to 1.37 and 1.17, respectively (P < 0.0001 and 0.028). A strongly significant interaction with gene-drinking was also observed. Among drinkers, the adjusted OR for Hap1 relative to Hap2 was increased to 2.50 (95% CI, 2.40 to 2.61; P < 0.0001). This was the first study to perform association analysis of the KLKB1 gene with essential hypertension. Our findings suggested that common genetic variation in the KLKB1 gene might contribute to the risk of hypertension in the northern Han Chinese population. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Conflict of interests: None.