用点突变的方法组建巨细胞病毒抗原决定簇基因的表达克隆

研究资料表明，人巨细胞病毒（ＨＣＭｖ）单一蛋白的单一抗原决定簇只能被部分患者阳性血清识别。组建在血清学诊断中能够替代全病毒抗原的基因工程抗原，需要含有病毒多种主要抗原蛋白的抗原决定簇。为搞清在表达载体中重复插入某一抗原决定簇基因是否能表达出更高抗原效价的融会蛋白，我们用点突变的方法，在表达载体中分别插入了人ＨＣＭｖ的ｐｐＵＬ３２蛋白羧基端一个抗原决定簇基因的１个、２个和３个拷贝。在免疫转印检测中，这些克隆表达的融合蛋白与特异性阳性血清的反应性差别不明显。这表明，插入表达载体中目的基因的多寡对表达蛋白的抗原效价没有显著影响。     

Saquinavir plus ritonavir reduce viral load by 99.9 percent

A combination of two protease inhibitors, saquinavir (Invirase) and ritonavir (Norvir), may produce a median drop in viral load of 99.9 percent. Several dosage variations were tested. The most common side effects of the combination regimen included tingling around the mouth, diarrhea, fatigue, and nausea. A low level of toxicity was found. This combination may be used for people who have failed other protease inhibitor therapy or have developed a resistance to nucleoside analogues.     

Banish those side effects

Although many AIDS patients suffer side effects from their medications, not all do, and many side effects can be managed. Many patients suffer needless pain because physicians are reluctant to prescribe potentially addictive drugs. Patients may find relaxation techniques helpful in managing nausea, and should vary the use of their drugs to avoid developing an aversion to its taste. Patients should also ask for medications that can alleviate the side effects associated with some drugs.     

Understanding and treating protease paunch

The changes and complications in metabolic status and lipodystrophy stemming from HIV treatment are examined. Research results from international conferences are discussed; topics include mechanisms of action and outcomes of recent treatments for lipodystrophy. These therapies cite the benefits of diet and exercise and the use of liposuction. Also examined are studies that investigated the effects of switching HIV protease drugs. Concluding comments address the possible connection between heart disease and lipodystrophy.     

A look at lab numbers

Lab analyses show that children with HIV differ in disease characteristics from HIV-infected adults. In children, viral load and T-cells are higher initially, but gradually decline and achieve a plateau by age six. Like adults, both T-cells and two separate viral load levels must be considered when deciding on therapy. CD4+ cell counts below 25 percent of normal age levels warrant therapy. There is a substantial overlap in viral load levels in the first year of life between children who have rapid disease progression and those who do not. One study revealed that the average viral load for the first year of life was 185,000. For children below 2 years of age, viral load needs to multiply or decrease by five times to be considered a significant change, compared to a threefold difference for persons more than 2 years of age.     

Norvir capsules-soon?

Abbott Laboratories reports that it expects to put its Norvir (Ritonavir) capsules back on the market around July. Abbott reported a manufacturing problem with the capsule last year. The company cited the FDA requirements of 6-month stability data before re-introduction.