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A S Debertin

Publications and source records attributed to A S Debertin.

9 recordsLinked to original sources

Density of dendritic cells in the human tracheal mucosa is age dependent and site specific.

BACKGROUND: The mucosal immune system undergoes extensive changes in early childhood in response to environmental stimuli. Dendritic cells (DC) play a major role in the development of the immune system. However, few data exist on the influence of continuous environmental stimulation on the distribution and phenotype of human airway DC. METHODS: Human tissue samples are mostly paraffin embedded which limits the use of several antibodies, and respiratory tissue for cryopreservation is difficult to obtain. Human frozen post mortem tracheal tissue was therefore used for this study. Only samples with epithelial adherence to the basement membrane were included (n = 34). Immunohistochemical staining and sequential overlay immunofluorescence were performed with DC-SIGN and a panel of leucocyte markers co-expressed by DC. RESULTS: DC detected in the human tracheal mucosa using DC-SIGN correlated with the expression of HLA-DR, co-stimulatory and adhesion molecules. Higher cell densities were found at the ventral tracheal site of patients older than 1 year than in infants in the first year of life. CONCLUSION: The increasing population of mucosal DC with age could reflect immunological maturation.

Adult↗

Coincidence of different structures of mucosa-associated lymphoid tissue (MALT) in the respiratory tract of children: no indications for enhanced mucosal immunostimulation in sudden infant death syndrome (SIDS).

Mucosa-associated lymphoid tissue (MALT) is the principal inductive site for mucosal immune responses that are capable of T and B cell responses and antigen-specific responses. In previous independent studies different structures of MALT, e.g. bronchus-, larynx- and nose-associated lymphoid tissue (BALT, LALT, NALT) have been described separately in various frequencies in the human respiratory tract over life spans. Because upper respiratory tract infections are common in infants, dysregulations of mucosal immune responses might be seriously involved in the aetiology of sudden infant death syndrome (SIDS). In the present study the coincidental occurrence of the three different MALT structures in the respiratory tract within the same patients were studied, and cases of SIDS and children who had died from different traumatic and natural causes of death (non-SIDS) were compared. First, the frequency of BALT and LALT in 46 children (35 SIDS, 11 non-SIDS) with or without NALT were examined. A tendency was found of a coincidence of respiratory MALT structures. In 50 additional cases of infant death (30 SIDS, 20 non-SIDS) from the multi-centric German Study on Sudden Infant Death Syndrome (GeSID) where death had occurred in the first year of life, the coincidence was evaluated. A coincidental occurrence of BALT, LALT and NALT or BALT and LALT (each about 30%) was found in both groups, whereby the coincidence in SIDS and the control patients did not differ. Interestingly, the children with coincidental MALT were strikingly older, supporting the hypothesis of respiratory MALT formation via environmental stimulation over time.

Bronchi↗

Nasal-associated lymphoid tissue (NALT): frequency and localization in young children.

In mucosal immunology nasal-associated lymphoid tissue (NALT) is taken as a constitutive structure of the nasal immune system and as a target tissue in strategies of local defence and an induction site for vaccination. These concepts are based on findings in rodents, but it has not been investigated systematically whether NALT also is present in humans and if so in which amount and localization. In a postmortem study the presence of NALT in humans is documented as a morphologically distinct structure additional to the lymphoid structures of the Waldeyer's ring. Human nasal tissue blocks of 150 children who had died in the first two years of life either of sudden infant death (n = 109) without signs of respiratory tract infections or of different traumatic (n = 22) and natural causes of death (n = 19) were obtained using a specific autopsy-technique and were investigated systematically using histology. Clearly in contrast to rodents human NALT was found disseminated in the nasal mucosa with typical morphological features in 38% of all children, mainly in the middle concha, with similar morphology and frequency in the examined groups. No correlation was found between the presence of NALT and the cause of death and especially the grade of inflammation in general. Therefore, NALT might be the morphological basis for inhalative vaccination strategies in young children and play a role in mucosal host defence.

Animals↗

Vaginorectal impalement injury in a 2-year-old child--caused by sexual abuse or an accident?

Anogenital impalement injuries are rarely encountered in clinical or forensic practice. If seen in children and if incurred under suspect circumstances, sexual abuse must be considered in the differential diagnosis. Here we describe the case of a 2-year-old girl admitted to hospital with a vaginorectal impalement injury. According to the girl's parents, she had slipped in the bathroom and fallen onto the handle of an upright toilet bowl brush. Since a second slight anal injury was present, the parents' account appeared inconsistent. Therefore, physicians from the Institute of Legal Medicine were consulted to investigate the possibility of underlying sexual abuse. Because they could not rule out that the injuries could have been caused by sexual abuse, they recommended having the police immediately examine the site of the purported accident for evidence. The police and forensic investigations, however, verified the parents' account of an accidental injury. Thus, in this case, the initiation of a police inquiry, which is not compulsory in Germany even when sexual abuse is strongly suspected, led to the exoneration of the father.

Anal Canal↗

Similarities and differences in lectin cytochemistry of laryngeal and tracheal epithelium and subepithelial seromucous glands in cases of sudden infant death and controls.

BACKGROUND: It has been speculated that non-specific defence mechanisms of the epithelium and subepithelial seromucous glands play a role in the larynx and lungs in cases of sudden infant death. METHODS: The larynx and trachea from five children who had died of sudden infant death (SID) syndrome and five control cases of comparable age were compared for the presence of lectin binding sites (12 different lectins tested). RESULTS: The secretory product of mucin producing cells contained carbohydrates including galactose and sialic acids. Binding sites for fucose and N-acetyl-galactosamine were only present in some of the specimens and distribution revealed no correlation between cases of SID and controls. Epithelial cells and serous cells of seromucous glands contained binding sites for sialic acid in cases of SID and controls. Moreover, binding sites for mannose were detected in these cells but were only present in SID cases. The difference between the SID and control groups as to the presence/expression of concanavalin A was highly significant. CONCLUSIONS: It is suggested that mucus hypersecretion in SID occurs in response to bacterial toxins or viral infection and is not specific. The different binding sites for mannose in cases of SID and controls could indicate differences in the production of antimicrobial peptides. A disturbed expression pattern of antimicrobial peptides in children who later succumb to SID could be responsible for an imbalance of the local microflora with a higher density of microorganisms on the mucosa. Further studies are required to elucidate the pattern of expression of antimicrobial peptides in subsequent SID victims.

Binding Sites↗

Dendritic cells in the mucosa of the human trachea are not regularly found in the first year of life.

BACKGROUND: Dendritic cells (DCs) in the mucosa of the respiratory tract might be involved in the early development of pulmonary allergy or tolerance. To date, little is known about when the first DCs occur in human airways. METHODS: Specimens of the distal trachea from patients who had died from sudden death in the first year of life (n=29) and in older age groups (n=59) as well as from those who had died from respiratory tract infections in the first year of life (n=8) were examined by immunohistochemistry. Transmission electron microscopy was performed in additional samples from two adults. RESULTS: In the sudden death subgroup DCs were absent in 76% of those who died in the first year of life but were present in 53 of the 59 older cases. All infants who had died of respiratory infectious diseases had DCs in the tracheal mucosa. CONCLUSIONS: Mature DCs are not constitutively present in the human tracheobronchial mucosa in the first year of life, but their occurrence seems to be triggered by infectious stimuli. These data support the hypothesis that DCs play a crucial role in immunoregulation in early childhood.

Adolescent↗

Tissue distribution of components of the insulin-like growth factor system in sudden infant death and controls.

Growth factors may be involved in sudden infant death (SID). Among these factors, the insulin-like growth factor (IGF) family is important in human fetal and perinatal organ growth and development. In order to detect probable differences in the occurrence and distribution of components of the IGF system, tissue samples from liver, lung, skin, parotid and thyroid gland, gut and cerebellum from SID children (n=9) and controls (n=6) aged between 14 and 258 days of life (mean 105 days) were stained immunohistochemically using antibodies against IGF-I, IGF-II and their specific IGF-I-receptor (IGF-IR). In contrast to controls in hepatocytes of SID children a reduction or an absence of immunoreactivity for IGF-I and IGF-IR and a weaker staining for IGF-II was detected. IGF-II in smooth muscle layers in the gut and IGF-I in epithelial cells in intestinal specimens also showed a reduced immunoreactivity in SID children and those who died traumatic deaths. In the other organs examined no significant differences in the distribution of the insulin-like growth factor system between the groups could be detected, indicating that in SID children no fundamental differences or alterations in the physiology of the IGF system occur. Because of the decreased immunostaining of IGFs in the liver and intestine of SID cases, a local dysregulation may be discussed.

Autopsy↗

[Death caused by neglect?].

Over a period of several months a 23-year-old bedridden woman suffered from increasing cachexia with numerous decubital ulcera in the parental house. The parents induced the hospitalization not before the patient reached the agonal phase. The reported case was especially spectacular because the left arm had fallen off and lay beside the woman showing maggot infestation, mummification and skeletonization. Against the parents a preliminary investigation for manslaughter by negligence was instituted. This case report describes the unusual course of disease and the striking familiar situation.

Adult↗