Careful preparation, often including anti-tuberculosis cover, and timing of pneumonectomy are essential. Meticulous anaesthetic and surgical technique and co-operation are critical. Bronchus blockers functioned well but are not without risk. Attention to detail makes pneumonectomy safe in childhood.

This is the first set of data on the causes of CLD in HIV-infected children in a developing country. Every effort should be made to identify the infectious agent, whether M. tuberculosis or a secondary bacterial infection in LIP, in order to treat most appropriately these children with lung disease.

Neoadjuvant chemotherapy appropriate to the pre-operative stage caused reduction in intravascular tumour in 18 (45%) patients, allowing 3 children who had atrial tumour at presentation to be surgically managed without recourse to cardiopulmonary bypass. Neoadjuvant chemotherapy also provided a window of opportunity to assess and manage co-morbidity especially malnutrition. Of the inception cohort, 31 (78%) underwent surgical resection; 23 had simple cavotomy, one caval resection and seven resection under cardiopulmonary bypass. There was one post-operative death. 77% of resected specimen contained viable malignant cells despite one or more cycles of neoadjuvant chemotherapy. Retrograde extension into caval tributaries threatened the completeness of resection in all patients necessitating the addition of post-operative radiotherapy. Of nine patients who did not undergo resection, five died pre-operatively. Three of these children died of chemotherapy induced neutropaenic sepsis. Four patients refused surgical treatment. Twenty-three patients completed the post-operative treatment protocol (1,203 characters).

19HIV has been reported to be cytotoxic in vitro and in lymph node infection models. Using 20 a computational approach, we found that partial inhibition of transmission which 21 involves multiple virions per cell could lead to increased numbers of live infected cells if 22 the number of viral DNA copies remains above one after inhibition, as eliminating the 23 surplus viral copies reduces cell death. Using a cell line, we observed increased 24 numbers of live infected cells when infection was partially inhibited with the antiretroviral 25 efavirenz or neutralizing antibody. We then used efavirenz at concentrations reported in 26 lymph nodes to inhibit lymph node infection by partially resistant HIV mutants. We 27 observed more live infected lymph node cells, but with fewer HIV DNA copies per cell, 28 relative to no drug. Hence, counterintuitively, limited attenuation of HIV transmission per 29 cell may increase live infected cell numbers in environments where the force of infection 30 is high. 31

HIV has been reported to be cytotoxic in vitro and in lymph node infection models. Using a computational approach, we found that partial inhibition of transmissions of multiple virions per cell could lead to increased numbers of live infected cells. If the number of viral DNA copies remains above one after inhibition, then eliminating the surplus viral copies reduces cell death. Using a cell line, we observed increased numbers of live infected cells when infection was partially inhibited with the antiretroviral efavirenz or neutralizing antibody. We then used efavirenz at concentrations reported in lymph nodes to inhibit lymph node infection by partially resistant HIV mutants. We observed more live infected lymph node cells, but with fewer HIV DNA copies per cell, relative to no drug. Hence, counterintuitively, limited attenuation of HIV transmission per cell may increase live infected cell numbers in environments where the force of infection is high.