The identification of circular extrachromosomal DNA in the nuclear genome of Trypanosoma brucei.

Nuclear extrachromosomal DNA elements have been identified in several kinetoplastids such as Leishmania and Trypanosoma cruzi, but never in Trypanosoma brucei. They can occur naturally or arise spontaneously as the result of sublethal drug exposure of parasites. In most cases, they are represented as circular elements and are mitotically unstable. In this study we describe the presence of circular DNA in the nucleus of Trypanosoma brucei. This novel type of DNA was termed NR-element (NlaIII repeat element). In contrast to drug-induced episomes in other kinetoplastids, the T. brucei extrachromosomal NR-element is not generated by drug selection. Furthermore, the element is stable during mitosis over many generations. Restriction analysis of tagged NR-element DNA, unusual migration patterns during pulsed field gel electrophoresis (PFGE) and CsCl/ethidium bromide equilibrium centrifugation demonstrates that the NR-element represents circular DNA. Whereas it has been found in all field isolates of the parasites we analysed, it is not detectable in some laboratory strains notably the genome reference strain 927. The DNA sequence of this element is related to a 29 bp repeat present in the subtelomeric region of VSG-bearing chromosomes of T. brucei. It has been suggested that this subtelomeric region is part of a transition zone on chromosomes separating the relatively stable telomeric repeats from the recombinationaly active region downstream of VSG genes. Therefore, we discuss a functional connection between the occurrence of this circular DNA and subtelomeric recombination events in T. brucei.

Nut allergy: symptom and severity reporting.

Nut allergy, in particular peanut allergy, is becoming more common in children. Immune sensitisation to nuts appears to be occurring earlier in life. High incidence of other allergic diseases in children with nut allergy. Onset of anaphylactic symptoms is quick but symptoms last for a short time. Necessity for hospital admission due to severity of allergic reaction is low.

Psychological and spiritual growth in women living with HIV.

Women living with HIV and AIDS face tremendous obstacles to wellness, yet many find ways to use their experience of HIV as a vehicle for psychological and spiritual growth. A qualitative study was conducted to better understand this process. Thirty-four women living with various stages of HIV were interviewed. Five components were found to be important in their psychological and spiritual growth: reckoning with death, life affirmation, creation of meaning, self-affirmation, and redefining relationships. Implications for social work practice and future research are discussed.

Teen perspectives on HIV and the relevance of Hawaii's health providers.

Based on focus group interviews with adolescents from an urban Honolulu community, the present article describes how these adolescents view HIV, HIV-prevention and the role of health care providers in addressing HIV-related needs. Although medical providers are known to be knowledgeable experts in a variety of health care areas, other research points to an underutilization of this potential. While knowledgeable about HIV, many of the youth in this study continue to engage in risky behavior. Few perceive they have others they can meaningfully talk to about their HIV and other health concerns. Even when probed for, almost none of these teens saw health care providers as pertinent to HIV or their health beyond the traditional illness/prescription role. Suggestions for ways to get more involved in the prevention of HIV and, more generally, positive health development in teens are discussed.

Two brothers with an unbalanced 8;17 translocation and infantile pyloric stenosis.

Two half-brothers are described who had developmental delay and minor dysmorphic features, both of whom had operative treatment for pyloric stenosis. They had identical unbalanced karyotypes: 46,XY,-17,+der(17)t(8;17) (q24;q25). This was inherited from their mother who had the balanced form of the translocation. She was of normal intelligence and had no history of pyloric stenosis herself or in her extended family. It is suggested that the unbalanced chromosomal rearrangement could have been associated with the development of pyloric stenosis in these two brothers.

Pseudotrisomy 13 and autosomal recessive holoprosencephaly.

Two sibs, diagnosed prenatally, had holoprosencephaly, midface hypoplasia, and normal chromosomes. The first fetus also had polydactyly. This sibship may represent an example of autosomal recessive pseudotrisomy 13.