DNA from Porphyromonas gingivalis and Tannerella forsythia induce cytokine production in human monocytic cell lines.

Toll-like receptor 9 (TLR9) expression is increased in periodontally diseased tissues compared with healthy sites indicating a possible role of TLR9 and its ligand, bacterial DNA (bDNA), in periodontal disease pathology. Here, we determine the immunostimulatory effects of periodontal bDNA in human monocytic cells (THP-1). THP-1 cells were stimulated with DNA of two putative periodontal pathogens: Porphyromonas gingivalis and Tannerella forsythia. The role of TLR9 in periodontal bDNA-initiated cytokine production was determined either by blocking TLR9 signaling in THP-1 cells with chloroquine or by measuring IL-8 production and nuclear factor-kappaB (NF-kappaB) activation in HEK293 cells stably transfected with human TLR9. Cytokine production (IL-1beta, IL-6, and TNF-alpha) was increased significantly in bDNA-stimulated cells compared with controls. Chloroquine treatment of THP-1 cells decreased cytokine production, suggesting that TLR9-mediated signaling pathways are operant in the recognition of DNA from periodontal pathogens. Compared with native HEK293 cells, TLR9-transfected cells demonstrated significantly increased IL-8 production (P < 0.001) and NF-kappaB activation in response to bDNA, further confirming the role of TLR9 in periodontal bDNA recognition. The results of PCR arrays demonstrated upregulation of proinflammatory cytokine and NF-kappaB genes in response to periodontal bDNA in THP-1 cells, suggesting that cytokine induction is through NF-kappaB activation. Hence, immune responses triggered by periodontal bacterial nucleic acids may contribute to periodontal disease pathology by inducing proinflammatory cytokine production through the TLR9 signaling pathway.

Infant growth patterns in the slums of Dhaka in relation to birth weight, intrauterine growth retardation, and prematurity.

BACKGROUND: Relations between size and maturity at birth and infant growth have been studied inadequately in Bangladesh, where the incidence of low birth weight is high and most infants are breast-fed. OBJECTIVE: This study was conducted to describe infant growth patterns and their relations to birth weight, intrauterine growth retardation, and prematurity. DESIGN: A total of 1654 infants born in selected low-socioeconomic areas of Dhaka, Bangladesh, were enrolled at birth. Weight and length were measured at birth and at 1, 3, 6, 9, and 12 mo of age. RESULTS: The infants' mean birth weight was 2516 g, with 46.4% weighing <2500 g; 70% were small for gestational age (SGA) and 17% were premature. Among the SGA infants, 63% had adequate ponderal indexes. The mean weight of the study infants closely tracked the -2 SD curve of the World Health Organization pooled breast-fed sample. Weight differences by birth weight, SGA, or preterm categories were retained throughout infancy. Mean z scores based on the pooled breast-fed sample were -2.38, -1. 72, and -2.34 at birth, 3 mo, and 12 mo. Correlation analysis showed greater plasticity of growth in the first 3 mo of life than later in the first year. CONCLUSIONS: Infant growth rates were similar to those observed among breast-fed infants in developed countries. Most study infants experienced chronic intrauterine undernourishment. Catch-up growth was limited and weight at 12 mo was largely a function of weight at birth. Improvement of birth weight is likely to lead to significant gains in infant nutritional status in this population, although interventions in the first 3 mo are also likely to be beneficial.

Colonization of the oropharynx with Gram-negative bacilli in children with severe protein-calorie malnutrition.

Oral pharyngeal isolation of Gram-negative bacteria was compared in four groups of Bengali children; acutely ill, severely malnourished outpatients swabbed on hospital admission; ill but less severely malnourished outpatients from the same area as the malnourished children; orphans also less severely malnourished but not acutely ill; and well controls drawn from a priviledged socioeconomic group. The expected weight for height percentage (National Center Health Statistics/Center for Disease Control median) of the four groups was respectively 67, 91, 97, and 97%. Isolation of Gram-negative bacteria from 74 of 87 (85%) severely malnourished children was significantly greater (p less than 0.01) compared to 43 of 113 (38%) outpatients, to 20 of 93 (22%) orphans, and to five of 51 (10%) controls. A total of 71 malnourished children under 5 yr of age (90%) had higher rates of Gram-negative throat colonization than did 16 older children (63%) (p less than 0.01). Thus there was an increased rate of Gram-negative colonization in severely malnourished children especially among the younger age group. In the subset of ill children, Gram-negative pharyngeal colonization was significantly associated inversely with nutritional indices and age. The high rate of such carriage may be partly responsible for the increased susceptibility of Gram-negative infection demonstrated in these children.

Xerophthalmia, protein-calorie malnutrition, and infections in children.

All children with evidence of xerophthalmia who were admitted to an inpatient facility for treatment of severe protein-calorie malnutrition and its complications were compared to other inpatients with severe PCM but free from signs or symptoms of vitamin A deficiency. Xerophthalmic inpatients were older and had more severe hypoproteinemia than inpatients without eye signs, and were more undernourished by anthropometric criteria than a comparison group matched for age, sex, and type of PCM. Children with more severe eye lesions were more retarded in growth than those with minimal ocular signs. All inpatients had high rates of bacterial infections, regardless of their vitamin status. However, xerophthalmic children had a highly significant increase in the rate of positive urine cultures. Mortality rates were similar in all study groups.

Cerebrovascular diseases. (A report of 53 cases).

Fifty-three patients suffering from cerebrovascular disease admitted to the Neurology unit of the Institute of Postgraduate Medicine and Research, Dacca, have been analyzed. It has been observed that the age incidence, sex ratio, causes and clinical pattern of cerebrovascular diseases are similar in developed and developing countries.