ZrO2 obtained by the sol-gel method: influence of synthesis parameters on physical and structural characteristics

The effects of some synthesis parameters, such as alcohol/alcoxide and water/alcoxide molar ratios, type of solvent and reaction temperature, on the physical and crystalline characteristics of ZrO₂ prepared by the sol-gel method were studied. The results show that gelling time, weight loss, surface area, pore-size distribution and crystalline phases were influenced by the preparation conditions.     

Intestinal mucosal inflammation associated with human immunodeficiency virus infection

The role of the human immunodeficiency virus type-1 (HIV) in producing intestinal disease was studied prospectively in 74 HIV-infected individuals with (43) or without (31) the acquired immunodeficiency syndrome (AIDS). Thirty-one subjects had enteric infections; all but one had AIDS. Alteration in bowel habits was the most common symptom and occurred independently of enteric infections. Abnormal histopathology was present in 69% of cases, and the finding was associated with altered bowel habits. An HIV-associated protein, p24, was detected in 71% of biopsies by ELISA assay. Tissue p24 contents varied with disease stage and were highest in HIV-infected individuals without AIDS (Walter Reed classes 3 and 4). Tissue p24 detection was associated with both altered bowel habits and histologic mucosal abnormalities. Tissue contents of the cytokines, tumor necrosis factor-alpha and interleukin-1 beta, were higher in HIV-infected individuals than in controls and their elevations were independent of enteric infection. We conclude that HIV reactivation in the intestinal mucosa may be associated with an inflammatory bowel syndrome in the absence of other enteric pathogens.     

The nursing management of women experiencing preterm labor: clinical guidelines and why they are needed

Nursing care is a critical component of therapy for women experiencing preterm labor. Diversity exists, however, in the level of comprehensiveness and consistency in guidelines for clinical practice. Nonstandardized care interferes with the ability to achieve consistent, positive patient care outcomes. This article is intended for nurses who seek to organize and standardize their care for women experiencing preterm labor. This article presents a review of the applicable practice and research literature. Clinical guidelines for the nursing management of women experiencing preterm labor are presented in the appendix.     

Young child feeding in a rural area in the Red River delta, Vietnam

Infant and young child feeding practices were investigated in a sample survey (1132 mothers) in a rural area in northern Vietnam. Pre-lacteal feeding was almost universal. Mean duration of breast feeding was 17 months, but foods other than breast milk were introduced early. Only 50% of infants between 3 and 5 months of age were predominantly breast fed. The educational level of the mother was strongly associated with breast feeding duration, with illiterate mothers breast feeding the longest. Christian mothers breast fed for longer than non-Christians. Very few were using feeding bottles at the time of the study, although formulas and bottles have recently been appearing on the local market. The breast feeding pattern described together with the rapidly changing social and economic situation in Vietnam could mean a risk of rapid decline in breast feeding.     

The mucosal adjuvant activities of ADP-ribosylating bacterial enterotoxins

The bacterial enterotoxins, cholera toxin and the heat labile toxin of E. coli, are well known adjuvants for mucosal immune response. Their common A chain mediates the toxigenic mechanism by causing ADP ribosylation of G proteins and subsequent elevation of cAMP in target cells. A large IgA and IgG antibody response to admixed protein antigen (Ag) is the hallmark of these adjuvants and is clearly associated with the A chain activity. Expansion of Ag-specific B and T cells, alteration of T cell cytokine production, and changes in regulatory T cells have been reported as adjuvant mechanisms. The B chain derivatives of these toxins can also weakly enhance immune response, especially if covalently associated with Ag and used for nasophyrangeal immunization. Importantly, these toxins or their B chain derivatives can alter the normal immune regulation that produces oral tolerance. This indicates that they modulate mechanisms operative between the mucosal and systemic immune systems. There are some discrepancies between in vitro models of CT or LT activity and in vivo manifestations of their adjuvant activities. Interpretation of current data regarding in vivo mechanism is hampered by an incomplete understanding of how mucosal B and T cells can interact with systemic lymphoid tissue and vice versa. More important, there is no clear understanding of the early effects of the toxins on the local (and draining) mucosal lymphoid tissues. This is especially true in the critical areas of antigen presentation, T and B cell activation, and cytokine production.