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31.
Schumacher U Duku M Katoh M Jörns J Krause WJ 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2004,278(2):540-550
Mucins of the gastroduodenal junction are secreted by the mucous surface and mucus-producing glandular cells in the stomach, and by goblet cells and Brunner's glands in the duodenum. Developmental studies have demonstrated that Brunner's glands can arise from undifferentiated gastric epithelium and/or intestinal epithelium in the proximal duodenum. The aim of this study was to investigate the carbohydrate composition of mucins from this region and compare it with that of mucins from Brunner's glands to evaluate the probable evolution of mucins from these glands. Toward that end, paraffin sections from 13 mammalian species were stained by classic carbohydrate histochemistry and treated with 13 lectins. In general, the mucous surface cells of the stomach, pyloric glands, duodenal goblet cells, and Brunner's glands secretory epithelium had different lectin-binding patterns. However, the lectin-binding profile of the secretory epithelium of Brunner's glands resembled that of pyloric glands more closely than that of duodenal goblet cells and mucous surface cells of the stomach. Mucins from Brunner's glands and pyloric glands showed a greater terminal carbohydrate residue diversity than those of gastric mucous surface cells or duodenal goblet cells. The lectin-binding profile argues for the evolution of similar mucins from the epithelia of Brunner's glands and pyloric glands. The greater diversity of carbohydrate residues in mucins secreted by Brunner's glands suggests that their mucus is more adaptable. This may explain why Brunner's glands metaplasia rather than goblet cell metaplasia is seen in the mucosa adjacent to chronic intestinal ulcers. 相似文献
32.
Kamya MR Semitala FC Quinn TC Ronald A Njama-Meya D Mayanja-Kizza H Katabira ET Spacek LA 《African health sciences》2004,4(2):94-101
Introduction
Total Lymphocyte Count (TLC) has been found to be an inexpensive and useful marker for staging disease, predicting progression to AIDS and death and monitoring response to ART. However, the correlation between TLC and CD4 has not been consistent. Access to HAART is expanding in Kampala, Uganda, yet there are no published data evaluating the utility of TLC as inexpensive surrogate marker of CD4 cell count to help guide therapeutic decisions.Objective
To evaluate clinical illnesses and total lymphocyte count (TLC) as surrogate markers of the CD4 cell count in HIV infected persons being considered for ART.Methods
A total of 131 patients were enrolled and evaluated by clinical assessment, TLC and CD4 count. Clinical illnesses and TLC dichotomized at various cut-point values were used to determine the sensitivity, specificity, and positive and negative predictive values (PPV and NPV) for the diagnosis of CD4 count <200 cells/mm3 among 100 participants fulfilling criteria for WHO clinical stage 2 and 3.Results
A strong correlation was observed between TLC and CD4 (r = 0.73, p<0.0001). For all clinical syndromes, except pulmonary tuberculosis, the positive predictive values (PPV) for a CD4 count <200 cells/mm3 were high (>80%) but the negative predictive values (NPV) were low. Using the WHO recommended TLC cut-off of 1200 cells/mm3 to diagnose a CD4 less than 200 cells/mm3, the PPV was 100%, and the NPV was 32%.Conclusion
Our data showed a good correlation between TLC and CD4 cell count. However, the WHO recommended TLC cutoff of 1200 did not identify the majority of WHO stage 2 and 3 patients with CD4 counts less than 200 cells/mm3. A more rational use of TLC counts is to treat all patients with WHO stage 2 and 3 who have a TLC <1200 and to limit CD4 counts to patients who are symptomatic but have TLC of >1200. 相似文献33.
CD16+ monocytes represent 5-10% of circulating monocytes in healthy individuals and are dramatically expanded in several pathological conditions including AIDS and HIV-1-associated dementia (HAD). CD16+ monocytes constitutively produce high levels of pro-inflammatory cytokines and neurotoxic factors that may contribute to the pathogenesis of these disorders. Monocyte recruitment into the central nervous system (CNS) and other peripheral tissues in response to locally produced chemokines is a critical event in immune surveillance and inflammation and involves monocyte arrest onto vascular beds and subsequent diapedesis. Here we investigate the ability of CD16+ monocytes to undergo transendothelial migration (TEM) under constitutive and inflammatory conditions. CD16+ monocytes underwent TEM across unstimulated human umbilical vascular (HUVEC) and brain microvascular endothelial (BMVEC) cell monolayers in response to soluble fractalkine (FKN/CX3CL1). Stimulation with tumor necrosis factor (TNF) and interferon-gamma (IFN-gamma) induced high and low expression of membrane-bound FKN on HUVEC and BMVEC, respectively, together with expression of VCAM-1 and intercellular adhesion molecule-1 (ICAM)-1. By contrast, only HUVEC expressed CD62E while BMVEC remained negative. Both CD16- and CD16+ monocyte subsets adhered to TNF/IFN-gamma-stimulated HUVEC with higher frequency than to unstimulated HUVEC. Monocyte chemoattractant protein-1 (MCP-1) triggered efficient TEM of CD16- monocytes across TNF/IFN-gamma-stimulated HUVEC, whereas soluble FKN failed to induce TEM of CD16+ monocytes across stimulated HUVEC. These results demonstrate that stimulation with TNF and IFN-gamma triggers expression of membrane-bound FKN on both HUVEC and BMVEC, but prevents TEM of CD16+ monocytes in response to soluble FKN. Thus, pro-inflammatory CD16+ monocytes may contribute to the pathogenesis of HAD and other inflammatory CNS diseases by affecting the integrity of the blood-brain barrier as a consequence of their massive accumulation onto inflamed brain vascular endothelial cells expressing FKN and other adhesion molecules. 相似文献
34.
Tim Martin Mark A McDaniel Melissa J Guynn Jon M Houck C Chad Woodruff Joel Pearson Bish Sandra N Moses Dubravko Kici? Claudia D Tesche 《International journal of psychophysiology》2007,64(3):247-258
We measured brain activity using magnetoencephalography in five participants during ongoing tasks that included prospective memory, retrospective memory, and oddball trials. Sources were identified in the hippocampal formation and posterior parietal and frontal lobes. Posterior parietal cortex activation had an earlier onset in the prospective memory condition than retrospective memory or oddball conditions, a higher level of theta activity in the retrospective condition, and higher levels of upper alpha in the prospective and oddball conditions. Activation of the hippocampal formation had a longer duration in the retrospective memory and prospective memory conditions than the oddball condition, but prominent alpha and theta band activity was present in all three conditions. We interpret the early (87 ms) onset of activity in parietal cortex as evidence for an initial noticing of appropriate conditions for a PM response. Hippocampal activity may reflect a subsequent memory search for the intended action. 相似文献
35.
Canfield MC; Tamarappoo BK; Moses AM; Verkman AS; Holtzman EJ 《Human molecular genetics》1997,6(11):1865-1871
Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused
most often by mutations in the vasopressin V2 receptor (AVPR2). We studied
a family which included a female patient with NDI with symptoms dating from
infancy. The patient responded to large doses of desmopressin (dDAVP) which
decreased urine volume from 10 to 4 I/day. Neither the parents nor the
three sisters were polyuric. The patient was found to be a compound
heterozygote for two novel recessive point mutations in the aquaporin-2
(AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is
the site for inhibition of water permeation by mercurial compounds and is
located near to the NPA motif conserved in all aquaporins. Osmotic water
permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2
was not increased over water control, while expression of L22V cRNA
increased the Pf to approximately 60% of that for wild-type AQP2.
Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the
function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO
cells showed that the C181W mutant had an endoplasmic reticulum-like
intracellular distribution, whereas L22V and wild-type AQP2 showed endosome
and plasma membrane staining. Water permeability assays showed a high Pf in
cells expressing wild-type and L22V AQP2. This study indicates that AQP2
mutations can confer partially responsive NDI.
相似文献
36.
A 59-year-old man had proximal weakness and wasting that started in early childhood. EMG was "myopathic," serum CK activity was increased, and muscle biopsy showed accumulations of glycogen. Biochemical studies revealed elevated glycogen concentration and absence of myophosphorylase activity. This unusual presentation of a long-standing, painless, and quite static weakness due to myophosphorylase deficiency represents another example of clinical heterogeneity. 相似文献
37.
This study investigated the impact of the administration of HAART and anti-Koch's, singly and in combination, on sexual competence and birth statistics. Adult male Wistar rats were randomised into distilled water-treated control, HAART-treated, anti-Koch's-treated and HAART + anti-Koch's-treated groups. The 56-day oral treatment led to impaired sexual competence evident by significantly reduced motivation to mate, prolonged latencies of mount, intromissions, ejaculations and post-ejaculatory interval, as well as reduced frequencies of mount, intromissions and ejaculations. This was accompanied by significant reductions in penile erection reflex and penile grooming. HAART and anti-Koch's, when administered singly or in combination, also led to significant reductions in the circulatory follicle-stimulating hormone, luteinizing hormone, testosterone and intratesticular testosterone, but a significant rise in prolactin. Also, HAART and/or anti-Koch's significantly reduced sperm count, sperm motility, sperm viability and spermatozoa with normal morphology. Furthermore, HAART and anti-Koch's, separately or in combination, significantly lowered fertility capacity, litter size and litter weight and offspring survival. The deleterious effects of these drugs were more pronounced when combined. Findings of the present study revealed that HAART and/or anti-Koch's impair sexual competence via a testosterone-dependent hyperprolactinemia-mediated mechanism. These events are associated with reduced fertility capacity, poor sperm quality and lowered offspring survival. 相似文献
38.
Carmen H Logie Moses Okumu Daniel Kibuuka Musoke Robert Hakiza Simon Mwima Peter Kyambadde Heather Abela Lesley Gittings Joshua Musinguzi Lawrence Mbuagbaw Stefan Baral 《Journal of the International AIDS Society》2021,24(3)
IntroductionHIV‐related risks may be exacerbated in humanitarian contexts. Uganda hosts 1.3 million refugees, of which 60% are aged under 18. There are knowledge gaps regarding HIV testing facilitators and barriers, including HIV and intersecting stigmas, among urban refugee youth. In response, we explored experiences and perspectives towards HIV testing strategies, including HIV self‐testing, with urban refugee youth in Kampala, Uganda.MethodsWe implemented a qualitative study with refugee cisgender youth aged 16 to 24 living in Kampala''s informal settlements from February‐April 2019. We conducted five focus groups with refugee youth, including two with adolescent boys and young men, two with adolescent girls and young women and one with female sex workers. We also conducted five key informant (KI) interviews with government, non‐government and community refugee agencies and HIV service providers. We conducted thematic analyses to understand HIV testing experiences, perspectives and recommendations.ResultsParticipants (n = 49) included young men (n = 17) and young women (n = 27) originally from the Democratic Republic of Congo [DRC] (n = 29), Rwanda (n = 11), Burundi (n = 3) and Sudan (n = 1), in addition to five KI (gender: n = 3 women, n = 2 men; country of origin: n = 2 Rwanda, n = 2 Uganda, n = 1 DRC). Participant narratives revealed stigma drivers included fear of HIV infection; misinformation that HIV is a “Ugandan disease”; and blame and shame for sexual activity. Stigma facilitators included legal precarity regarding sex work, same‐sex practices and immigration status, alongside healthcare mistreatment and confidentiality concerns. Stigma experiences were attributed to the social devaluation of intersecting identities (sex work, youth, refugees, sexual minorities, people living with HIV, women). Participants expressed high interest in HIV self‐testing. They recommended HIV self‐testing implementation strategies to be peer supported and expressed concerns regarding sexual‐ and gender‐based violence with partner testing.ConclusionsIntersecting stigma rooted in fear, misinformation, blame and shame, legal precarity and healthcare mistreatment constrain current HIV testing strategies with urban refugee youth. Findings align with the Health Stigma and Discrimination Framework that conceptualizes stigma drivers and facilitators that devalue intersecting health conditions and social identities. Findings can inform multi‐level strategies to foster enabling HIV testing environments with urban refugee youth, including tackling intersecting stigma and leveraging refugee youth peer support. 相似文献
39.
40.
H. N. Rosen R. Dresner-Pollak A. C. Moses M. Rosenblatt A. J. Zeind J. D. Clemens S. L. Greenspan 《Calcified tissue international》1994,54(1):26-29
Urinary excretion of cross-linked N-telopeptide of type I collagen (NTX) has been reported to be a specific indicator of bone resorption. We studied the utility of a new immunoassay for NTX as an indicator of changes in bone resorption caused by treatment with pamidronate (APD) followed by T3. Twenty-two male subjects received either placebo (Group 1) or APD on study days 1–2 (Group 2). One week later all subjects received T3 100 g/day (days 8–15). Urinary NTX, pyridinoline (PYD), hydroxyproline (HYP), and creatinine (cr) were measured on 2-hour fasting urine samples at baseline (day 1), after APD/placebo (day 8), after T3 (day 16), and at days 30 and 58. NTX/cr excretion fell 85% after treatment with APD (P<0.001 versus baseline), but not after placebo. The fall in mean urinary NTX after receiving APD was greater than the fall in PYD (25%) or HYP (31%) (P<0.001 NTX versus PYD and HYP). After treatment with APD, NTX excretion remained suppressed below baseline until day 58, whereas PYD and HYP excretion returned to baseline by study day 16. Persistence of APD's effect on bone until day 58 was suggested by the fact that serum calcium and parathyroid hormone levels had not returned to baseline by day 58. On day 16, after all subjects were treated with T3, urinary NTX/cr rose significantly (P<0.01) in Group 1 (-bisphosphonate) but not in Group 2 (+bisphosphonate). We conclude that urinary NTX is responsive to acute thyroid hormone-induced increases and bisphosphonate-induced decreases in bone resorption, and may reflect these changes more accurately than PYD or HYP.Portions of the data presented here were presented at the Fifteenth Annual Meeting of the American Society for Bone and Mineral Research, Tampa, Florida, September 18–22, 1993. 相似文献