Transplantation of in vitro-generated<Emphasis Type="Italic"> Schistosoma mansoni</Emphasis> mother sporocysts into<Emphasis Type="Italic"> Biomphalaria glabrata</Emphasis>

Specific studies on schistosome gene functions require both access to the parasite stages, preferably the larvae, and to complete the life cycle. In the present study, we investigated whether short-term in vitro cultivation of sporocysts and surgical transplantation into snails could be combined to produce cercariae. Miracidia were maintained in vitro in the presence of Biomphalaria glabrata embryonic (Bge) cells or, alternatively, in Bge-cell-conditioned medium. The transformation of miracidia to mother sporocysts was observed in both cases. Two day-old sporocysts were transplanted into the cephalopedal sinus of recipient snails. Transplantation efficiencies varied between 16% and 43%, depending on the culture of the sporocysts in terms of the number of cercariae producing snails. Cercariae recovered from these snails were used to successfully infect hamsters, demonstrating that short term in vitro-generated sporocysts undergo normal cercariogenesis following transplantation. This combination of in vitro cultivation and transplantation may be useful for novel experimental approaches to investigate the genes involved in larval development or host-parasite molecular interactions.     

Apparent genotype–phenotype correlation in childhood,adolescent, and adult Chediak‐Higashi syndrome

Chediak‐Higashi syndrome (CHS) is a rare autosomal recessive disorder characterized by severe immunologic defects, reduced pigmentation, bleeding tendency, and progressive neurological dysfunction. Most patients present in early childhood and die unless treated by bone marrow transplantation. About 10–15% of patients exhibit a much milder clinical phenotype and survive to adulthood, but develop progressive and often fatal neurological dysfunction. Very rare patients exhibit an intermediate adolescent CHS phenotype, presenting with severe infections in early childhood, but a milder course by adolescence, with no accelerated phase. Here, we describe the organization and genomic DNA sequence of the CHS1 gene and mutation analysis of 21 unrelated patients with the childhood, adolescent, and adult forms of CHS. In patients with severe childhood CHS, we found only functionally null mutant CHS1 alleles, whereas in patients with the adolescent and adult forms of CHS we also found missense mutant alleles that likely encode CHS1 polypeptides with partial function. Together, these results suggest an allelic genotype–phenotype relationship among the various clinical forms of CHS. © 2002 Wiley‐Liss, Inc.     

Tumor necrosis factor-mediated inhibition of interleukin-18 in the brain: a clinical and experimental study in head-injured patients and in a murine model of closed head injury.

Tumor necrosis factor (TNF) and interleukin-(IL)-18 are important mediators of neuroinflammation after closed head injury (CHI). Both mediators have been previously found to be significantly elevated in the intracranial compartment after brain injury, both in patients as well as in experimental model systems. However, the interrelation and regulation of these crucial cytokines within the injured brain has not yet been investigated. The present study was designed to assess a potential regulation of intracranial IL-18 levels by TNF based on a clinical study in head-injured patients and an experimental model in mice. In the first part, we investigated the interrelationship between the daily TNF and IL-18 cerebrospinal fluid levels in 10 patients with severe CHI for up to 14 days after trauma. In the second part of the study, the potential TNF-dependent regulation of intracerebral IL-18 levels was further characterized in an experimental set-up in mice: (1) in a standardized model of CHI in TNF/lymphotoxin-alpha gene-deficient mice and wild-type (WT) littermates, and (2) by intracerebro-ventricular injection of mouse recombinant TNF in WT C57BL/6 mice. The results demonstrate an inverse correlation of intrathecal TNF and IL-18 levels in head-injured patients and a TNF-dependent inhibition of IL-18 after intracerebral injection in mice. These findings imply a potential new anti-inflammatory mechanism of TNF by attenuation of IL-18, thus confirming the proposed "dual" function of this cytokine in the pathophysiology of traumatic brain injury.     

The response of hepatic angiotensinogen secretion to experimental inflammatory stimuli

Angiotensinogen is thought to be an acute-phase protein, since its plasma concentrations increase in response to some inflammatory conditions, e.g. partial hepatectomy, nephrectomy or lipopolysaccharide (LPS) injection. However, this response of angiotensinogen has never been related to that of established acute-phase proteins. We have, therefore, examined plasma concentrations and hepatic secretion of angiotensinogen in two widely used inflammation models, i.e. turpentine or LPS injection in the rat, as well as in nephrectomized and sham-nephrectomized rats, in comparison to the response of two established acute-phase proteins, ₁-acid glycoprotein (AGP) and ₁-macroglobulin (AMG). Plasma concentrations and secretion rates of AGP and AMG increased significantly in all the conditions examined. The magnitude of the response decreased in the order turpentine > nephrectomy = LPS > sham nephrectomy. Angiotensinogen secretion was stimulated in LPS-injected (2.5-fold) and nephrectomized rats (2.6-fold), whereas no changes were seen in sham-nephrectomized rats. Surprisingly, a significant decrease both in secretion rates and plasma concentrations of angiotensinogen occurred in turpentine-injected rats.Intraperitoneal injection of interleukin 6, a major inductor of hepatic acute-phase proteins, increased plasma concentrations and hepatic secretion rates of AGP, AMG and angiotensinogen. Changes in liver angiotensinogen mRNA correlated well with angiotensinogen secretion rates in all groups, indicating that alterations in angiotensinogen synthesis are responsible for the observed changes in secretion rates and plasma concentrations. The response of angiotensinogen to turpentine is difficult to reconcile with the conventional definition of an acute-phase protein.     

Brown and Eccles'' Depiction of Vagal Effects: An Old and Widely Used Method Reexamined

It can be shown that the procedure for representing the effect of the vagal innervation of the heart introduced by Brown and Eccles in 1934 distorts the actual course of the inhibitory effect. A corrected procedure is proposed. It is stressed that cycle phase specificity of the stimulation can be studied only by drawing different curves representing the course of the vagal effect for different times of stimulation within the cardiac cycle.     

Deep spatial profiling of human COVID-19 brains reveals neuroinflammation with distinct microanatomical microglia-T-cell interactions

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Evidence for a calcium regulated, bidirectional intronic promoter in the murine TCR V{alpha}1 gene

Previous studies of the TCR chain gene have located promoterelements 5' to the start of the various V genes. The only fullycharacterized enhancer for the entire chain gene (V, J andC genes) has been located {small tilde}3 kb from the 3' endof C. We now report the existence of additional regulatory elementslocated in the introns of several murine V genes (V1, V3 andVB6.2.16). In the case of V1, this element appears to be a promoterwith bidirectional activity that is not T cell specific. Interestingly,upstream of the promoter in the antisense strand, an open readingframe has been found that codes for a small molecular weightprotein ({small tilde}60 amino acids) that contains a prollne-richregion and a tyrosine-isoleucine motif that has homology toIgß (the B29 gene product). A rabbit antiserum madeagainst this sequence has confirmed its existence by Westernblot and immunoprecipitation. Thus this V1 intronic promoterhas the potential not only to induce the formation of a truncatedV1 gene product, but also regulates the expression of a smallmolecular weight protein that may be involved in lymphocyteantigen receptor signaling. The activity of this promoter isregulated by changes in intracellular calcium. In the presenceof ionomycin the promoter is down-regulated in the sense directionand its activity is enhanced in the antisense direction. Thisresult suggests that this promoter can act differentially toproduce two very different gene products. The bidirectionalV1 promoter appears to be the first in the Ig superfamily toinduce potentially functional proteins in both directions.     

IL-10 Secretion and Sensitivity in Normal Human Intestine and Inflammatory Bowel Disease

Interleukin-10 (IL-10) deficiency in gene knockout mice causes chronic enterocolitis. We hypothesized that inflammation in human inflammatory bowel disease might result from innate alterations in the IL-10 pathway. Serum, supernatants, and mRNA of peripheral blood mononuclear cells (PBMC) and lamina propria mononuclear cells (LPMC) derived from inflamed (LPMC-i) and noninflamed colonic mucosa (LPMC-ni) were collected from patients with Crohn's colitis, ulcerative colitis, and controls. IL-10 protein concentrations and IL-10 mRNA were examined in response to PMA/CD3 or PHA stimulation. The response to rhIL-10 was assessed by inhibition of tumor necrosis factor-alpha (TNF-), IL-6, and interferon-gamma (IFN-) production. Serum IL-10 levels of inflammatory bowel disease (IBD) patients were within the normal range. IL-10 concentrations in supernatants from LPMC-i were significantly lower than from LPMC-ni or PBMC. No difference was seen between samples from ulcerative colitis and Crohn's disease. IL-10 mRNA was detected in 0/4 LPMC-i samples compared to 1/6 LPMC-ni and 6/6 PBMC. RhIL-10 inhibited TNF-, IL-6, and IFN- synthesis in PBMC. This effect was strongly diminished in LPMC. Disease-specific alterations were not detected. Our data suggest that LPMC derived from inflamed colonic mucosa have a reduced ability to produce and to respond to rhIL-10. A disease-specific alteration in the IL-10 pathway, however, was not found.     

Intuitive Eating is Associated With Higher Fruit and Vegetable Intake Among Adults

ObjectiveAssess how intuitive eating relates to dietary intake.MethodsSurvey data were collected in Project Eating and Activity in Teens and Young Adults, the fourth wave of a longitudinal cohort study (weighted n = 1,830, 49% women; mean age = 31 years). Intuitive eating was assessed using a 7-item scale adapted from the Intuitive Eating Scale and Intuitive Eating Scale-2. Dietary intake was measured via a semiquantitative food frequency questionnaire. Mean servings were stratified by gender and intuitive eating quartiles and adjusted for sociodemographic characteristics and caloric intake.ResultsWomen and men in the top intuitive eating quartile consumed 0.6–0.3 servings more fruit and 0.4–0.6 servings more vegetables daily, respectively, compared with the bottom quartile, whereas men in the top quartile also consumed 0.6 servings fewer whole grains (all P < 0.05) than the bottom quartile.Conclusions and ImplicationsIntuitive eating shows promise as a healthier alternative to practices such as dieting.