1701. Genomic copy number variation, human health, and disease.
Despite the long recognised effects of chromosomal structural abnormalities and completion of the Human Genome Project, much of the structural variation in the genome has gone unrecognised until recently. Deletions and duplications of DNA strands of between a few hundred bp and several million bp-collectively referred to as copy number variants-are now known to be widespread. Since 2007, rigorous and adequately powered genome-wide association studies based on single nucleotide polymorphisms have yielded replicated associations to several common diseases. Some copy number variants explain rare, previously uncharacterised disorders, and they are now expected to explain some of the genetic contribution to common diseases. We review efforts to map copy number variants and discuss present and future prospects for assessment of their relation to human health and disease.
1703. Parkinson's disease.
Parkinson's disease is a common progressive bradykinetic disorder that can be accurately diagnosed. It is characterised by the presence of severe pars-compacta nigral-cell loss, and accumulation of aggregated alpha-synuclein in specific brain stem, spinal cord, and cortical regions. The main known risk factor is age. Susceptibility genes including alpha-synuclein, leucine rich repeat kinase 2 (LRRK-2), and glucocerebrosidase (GBA) have shown that genetic predisposition is another important causal factor. Dopamine replacement therapy considerably reduces motor handicap, and effective treatment of associated depression, pain, constipation, and nocturnal difficulties can improve quality of life. Embryonic stem cells and gene therapy are promising research therapeutic approaches.
1707. Bladder cancer.
Bladder cancer is a heterogeneous disease, with 70% of patients presenting with superficial tumours, which tend to recur but are generally not life threatening, and 30% presenting as muscle-invasive disease associated with a high risk of death from distant metastases. The main presenting symptom of all bladder cancers is painless haematuria, and the diagnosis is established by urinary cytology and transurethral tumour resection. Intravesical treatment is used for carcinoma in situ and other high grade non-muscle-invasive tumours. The standard of care for muscle-invasive disease is radical cystoprostatectomy, and several types of urinary diversions are offered to patients, with quality of life as an important consideration. Bladder preservation with transurethral tumour resection, radiation, and chemotherapy can in some cases be equally curative. Several chemotherapeutic agents have proven to be useful as neoadjuvant or adjuvant treatment and in patients with metastatic disease. We discuss bladder preserving approaches, combination chemotherapy including new agents, targeted therapies, and advances in molecular biology.
1710. Glucocorticoid resistance in inflammatory diseases.
Glucocorticoid resistance or insensitivity is a major barrier to the treatment of several common inflammatory diseases-including chronic obstructive pulmonary disease and acute respiratory distress syndrome; it is also an issue for some patients with asthma, rheumatoid arthritis, and inflammatory bowel disease. Several molecular mechanisms of glucocorticoid resistance have now been identified, including activation of mitogen-activated protein (MAP) kinase pathways by certain cytokines, excessive activation of the transcription factor activator protein 1, reduced histone deacetylase-2 (HDAC2) expression, raised macrophage migration inhibitory factor, and increased P-glycoprotein-mediated drug efflux. Patients with glucocorticoid resistance can be treated with alternative broad-spectrum anti-inflammatory treatments, such as calcineurin inhibitors and other immunomodulators, or novel anti-inflammatory treatments, such as inhibitors of phosphodiesterase 4 or nuclear factor kappaB, although these drugs are all likely to have major side-effects. An alternative treatment strategy is to reverse glucocorticoid resistance by blocking its underlying mechanisms. Some examples of this approach are inhibition of p38 MAP kinase, use of vitamin D to restore interleukin-10 response, activation of HDAC2 expression by use of theophylline, antioxidants, or phosphoinositide-3-kinase-delta inhibitors, and inhibition of macrophage migration inhibitory factor and P-glycoprotein.
1712. Neurofibromatosis type 2.
作者: Ashok R Asthagiri.;Dilys M Parry.;John A Butman.;H Jeffrey Kim.;Ekaterini T Tsilou.;Zhengping Zhuang.;Russell R Lonser.
来源: Lancet. 2009年373卷9679期1974-86页
Neurofibromatosis type 2 is an autosomal-dominant multiple neoplasia syndrome that results from mutations in the NF2 tumour suppressor gene located on chromosome 22q. It has a frequency of one in 25,000 livebirths and nearly 100% penetrance by 60 years of age. Half of patients inherit a germline mutation from an affected parent and the remainder acquire a de novo mutation for neurofibromatosis type 2. Patients develop nervous system tumours (schwannomas, meningiomas, ependymomas, astrocytomas, and neurofibromas), peripheral neuropathy, ophthalmological lesions (cataracts, epiretinal membranes, and retinal hamartomas), and cutaneous lesions (skin tumours). Optimum treatment is multidisciplinary because of the complexities associated with management of the multiple, progressive, and protean lesions associated with the disorder. We review the molecular pathogenesis, genetics, clinical findings, and management strategies for neurofibromatosis type 2.
1713. Pancreas transplantation.
Since the introduction of pancreas transplantation more than 40 years ago, efforts to develop more minimally invasive techniques for endocrine replacement therapy have been in progress, yet this surgical procedure still remains the treatment of choice for diabetic patients with end-stage renal failure. Many improvements have been made in the surgical techniques and immunosuppressive regimens, both of which have contributed to an increasing number of indications for pancreas transplantation. This operation can be justified on the basis that patients replace daily injections of insulin with an improved quality of life but at the expense of a major surgical procedure and lifelong immunosuppression. The various indications, categories, and outcomes of patients having a pancreas transplant are discussed, particularly with reference to the effect on long-term diabetic complications.
1714. Stress hyperglycaemia.
作者: Kathleen M Dungan.;Susan S Braithwaite.;Jean-Charles Preiser.
来源: Lancet. 2009年373卷9677期1798-807页
Results of randomised controlled trials of tight glycaemic control in hospital inpatients might vary with population and disease state. Individualised therapy for different hospital inpatient populations and identification of patients at risk of hyperglycaemia might be needed. One risk factor that has received much attention is the presence of pre-existing diabetes. So-called stress hyperglycaemia is usually defined as hyperglycaemia resolving spontaneously after dissipation of acute illness. The term generally refers to patients without known diabetes, although patients with diabetes might also develop stress hyperglycaemia-a fact overlooked in many studies comparing hospital inpatients with or without diabetes. Investigators of several studies have suggested that patients with stress hyperglycaemia are at higher risk of adverse consequences than are those with pre-existing diabetes. We describe classification of stress hyperglycaemia, mechanisms of harm, and management strategies.
1715. Gestational diabetes: the need for a common ground.
Gestational diabetes mellitus is a substantial and growing health concern in many parts of the world. Certain populations are especially vulnerable to developing this condition because of genetic, social, and environmental factors. Gestational diabetes has serious, long-term consequences for both baby and mother, including a predisposition to obesity, metabolic syndrome, and diabetes later in life. Early detection and intervention can greatly improve outcomes for women with this condition and their babies. Unfortunately, screening and diagnostic tests are not uniform worldwide, which could lead not only to underdiagnosis but also undermanagement of the illness. Here, we report the controversies surrounding the causes, screening, diagnosis, management, and prevention of gestational diabetes, and give specific recommendations for research studies to address the major issues of this medical condition.
1716. Type 2 diabetes mellitus after gestational diabetes: a systematic review and meta-analysis.
作者: Leanne Bellamy.;Juan-Pablo Casas.;Aroon D Hingorani.;David Williams.
来源: Lancet. 2009年373卷9677期1773-9页
Women with gestational diabetes are at increased risk of developing type 2 diabetes, but the risk and time of onset have not been fully quantified. We therefore did a comprehensive systematic review and meta-analysis to assess the strength of association between these conditions and the effect of factors that might modify the risk.
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