Differences in chromosome susceptibility to aneuploidy and survival to first trimester

The purpose of this study was to find specific rates of aneuploidy in cleavage-stage embryos compared with first trimester data and to evaluate post-zygotic selection against aneuploidy. A total of 2058 embryos were analysed by flurorescence in-situ hybridization (FISH), and specific aneuploidy rates were obtained for 14 chromosomes. Data from morphologically abnormal embryos could be pooled with data from preimplantation genetic diagnosis (PGD) cycles because it was observed that they had similar rates of aneuploidy; thus, for the purpose of studying aneuploidy they could be, and were, pooled. Specific chromosome aneuploidy rates were not related to morphology or development of the embryos. The average maternal age of patients with aneuploid embryos was significantly higher than the overall analysed population. Monosomy appeared more commonly than trisomy. The chromosomes most frequently involved in aneuploidy were (in order) 22, 16, 21 and 15. When compared with first trimester pregnancy data, aneuploidies detected at cleavage stage seem to die in excess of 90% before reaching first trimester, with the exception of chromosome 16 and gonosomes (76% and 14% respectively). Differences in chromosome-specific aneuploidy rates at first trimester conceptions are probably produced by different chromosome-specific aneuploidy rates at cleavage stage and different survival rates to first trimester.     

Cerebrospinal fluid and plasma concentrations of proinflammatory mediators in human immunodeficiency virus-infected children

BACKGROUND: The pathogenesis of HIV encephalopathy is poorly understood especially in children. Studies suggest that HIV replication and the release of proinflammatory mediators in the central nervous system contribute to the pathogenesis of HIV dementia in adults. METHODS: Cerebrospinal fluid (CSF) and plasma samples from 23 HIV-infected children were longitudinally analyzed at Weeks 0, 8, 16 and 48 for HIV RNA and concentrations of the following proinflammatory mediators: monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha, regulated upon activation, normal T cell expressed and secreted (RANTES), macrophage-inflammatory protein (MIP)-1-alpha, MIP-1-beta and matrix metalloproteinase-9 (MMP-9). RESULTS: All 23 children had detectable concentrations of MCP-1 in the CSF at all time points evaluated. However, of the remaining of proinflammatory mediators measured in CSF at baseline, only a few children had detectable concentrations: tumor necrosis factor-alpha, n = 1; RANTES, n = 5; MMP-9, n = 9; MIP-1-alpha and MIP-1-beta, n = 0. A reduction from baseline to Week 48 was observed in CSF concentrations of MCP-1 and, among children with detectable values, MMP-9, which paralleled declines in CSF HIV RNA. CONCLUSION: These results suggest that MCP-1 and MMP-9 may be involved in the pathogenesis of central nervous system disease in HIV-infected children.     

Adenovirus and respiratory syncytial virus-adenovirus mixed acute lower respiratory infections in Chilean infants

BACKGROUND: In Chile respiratory syncytial virus (RSV) and adenovirus (AD) are the principal viruses detected in acute lower respiratory infections (ALRI) in infants. An overview of AD pneumonia in Chile to detect annual trends and to compare the severity of single AD or mixed RSV-AD infections is presented. METHODS: Surveillance in 4927 infants hospitalized for ALRI has been performed from 1989 to 2001 using immunofluorescence assay (IFA) and viral isolation. Clinical features in 117 infants with single genotyped AD and 81 infants with mixed RSV-AD infections were analyzed. RESULTS: Adenovirus cases declined from 20% annually in the early 1990s to approximately 5% in the 2000 decade. Genotype 7h showed increasing prevalence in hospitalized cases. The mean annual burden of hospitalizations caused by AD in Santiago was estimated to be 0.6%. No difference was observed in duration of fever, oxygen requirement and hospital stay between groups. Lung consolidation was more frequent in AD cases than mixed cases (P < 0.01); interstitial pattern and hyperinflation prevailed in the mixed cases (P < 0.01). No child died. AD diagnosis was confirmed on admission by IFA in 17% of cases of RSV-AD and in 43% of cases of single AD ALRI. AD cases diagnosed early by IFA had worse clinical outcome than those diagnosed later by virus isolation (P < 0.05). CONCLUSIONS: AD cases declined since 1989. Mixed RSV-AD infections were not more severe than single AD etiology. AD cases admitted with positive IFA had worse prognoses than AD infections diagnosed later by virus isolation.     

Psychological and sociocultural perspectives on follow-up of abnormal Papanicolaou results

OBJECTIVE: To understand women's motivation to attend follow-up of an abnormal Papanicolaou (Pap) test by applying a general theoretical framework for voluntary behavior. METHODS: Semistructured, face-to-face interviews were conducted among 120 low-income, African-American, Caucasian, or Hispanic outpatients, aged 25-50 years, who presented for routine gynecologic care. Interview questions assessed social, cognitive, environmental, and emotional factors surrounding follow-up for an abnormal Pap test. Content analysis was performed. RESULTS: The majority of women (74%) described their attitude toward returning for a follow-up visit as favorable. Overall, knowledge regarding the significance of an abnormal result was poor, and misconceptions were common. Perceived barriers, consequences, and social influences associated with attending follow-up were qualitatively different across the 3 racial/ethnic groups. For example, African-American and Hispanic women expressed embarrassment more frequently than Caucasian women and were less likely to anticipate obstacles to attending follow-up. Furthermore, African-American women were the least likely to be influenced by others' opinions and to perceive difficulty in adhering to follow-up recommendations. For nearly all women, adequate communication with their provider was a key component of anticipated adherence. CONCLUSION: Clinicians may exert a positive influence on adherence among patients who experience an abnormal Pap test by engaging patients in a dialogue that accommodates the patient's sociocultural environment, explores concerns regarding the partner's reaction, emphasizes the importance of follow-up, provides a clear understanding of the process and timeline surrounding follow-up recommendations, and encourages the patient to anticipate obstacles to adherence and assists with solutions.     

Granulosa cell-oocyte interactions

Throughout oogenesis the oocyte and follicle cells establish an intricate system of mutual interactions that ultimately lead to the acquisition of their respective competences. Paracrine factors released by both cell types are believed to stimulate formation of the primordial follicle and support the initial phases of follicle growth. At the same time, these processes are also dependent on gap junction communication between the germinal and somatic compartment. At later stages of follicle development, activities released by the oocyte induce the adjacent granulosa cells to express a specialized phenotype. In their turn, these cells crucially regulate the ability of the oocyte to progress through the meiotic process and acquire full developmental potential.     

Biotic and abiotic determinants of seroprevalence of antibodies against Trypanosoma cruzi in Palmar de Bravo, Puebla, Mexico

OBJECTIVE: To establish the relationship between seroprevalence for antibodies against Trypanosoma cruzi and its relationship with biotic and abiotic factors. MATERIAL AND METHODS: A cross-sectional study was conducted between August 2000 and September 2001. The study population consisted of a simple random sample of 390 volunteers residing in Palmar de Bravo, Puebla, Mexico. Sample and data collection procedures included assaying antibodies against T. cruzi with validated assays, and searching for domestic reservoirs and triatomine bugs. The relationship between biotic and abiotic factors with seropositivity was assessed. Statistical analysis was conducted using Kappa values for diagnostic tests; statistical significance was assessed with 2 x 2 tables, chi-squared test with Yates' correction, Fisher exact test, and odds ratios. RESULTS: The seroprevalence of T. cruzi infection in humans was 4%; in domestic reservoirs (horses, pigs, and dogs) only 10% of canine reservoirs were positive. Vector species recognized were T. borberi and T. pallidipennis, with a Dispersion Area Index and a Colonization Index of 55% and 40%, respectively. The most important risk factors associated with positive serology were altitude (>2,150 and <2,180 meters above sea level), presence of triatomines, age, time of residence, and participation in a social assistance program. CONCLUSIONS: T. cruzi infection was identified in human beings, vectors, and possibly in domestic reservoirs, in communities located over 2,000 meters above sea level.     

Immunization with a tetramer derivative of an anti-inflammatory pentapeptide produced by Entamoeba histolytica protects gerbils (Meriones unguiculatus) against experimental amoebic abscess of the liver

Axenically grown Entamoeba histolytica produces a pentapeptide (Met-Gln-Cys-Asn-Ser) with several anti-inflammatory properties, including the inhibition of human monocyte locomotion (Monocyte Locomotion Inhibitory Factor (MLIF)). A construct displays the same effects as the native material. It remains to be seen if MLIF is used, or even produced in vivo by the tissue-invading parasite. If MLIF were to be relevant in invasive amoebiasis, immunizing against it could diminish this parasite advantage and prevent lesions. KLH-linked MLIF mixed with Freund's adjuvant was too aggressive an immunizing material to answer this question. However, immunization with a tetramer of MLIF (but not a scrambled version of MLIF) around a lysine core (MLIF-MAPS), that displays increased antigenicity, yet lacks excessive innate immunity activation, completely protects gerbils against amoebic abscess of the liver caused by the intraportal injection of virulent E. histolytica. Liver abscesses caused by Listeria monocytogenes were not prevented. Invasive E. histolytica may produce the parent protein of MLIF in vivo, and if appropriately cleaved, it may play a role in invasive amoebiasis. MLIF may join new vaccination strategies against amoebiasis.     

Indocyanine Green Alters Transepithelial Electrical Parameters of the Distal Colon

Indocyanine green (ICG) is used as a dye marker of the vascular space in gastroenterology, ophthalmology, neurology, and critical care medicine. It is widely regarded to be inert. We report, however, that ICG demonstrates effects on colonic transepithelial electrical parameters which could form a basis for a growing number of deleterious gastrointestinal and other clinical effects. Short-circuit current (Iscc), transepithelial conductance (gt), and transepithelial paracellular flux of 14C-D-mannitol were monitored across sheets of rat distal colon. Dye was introduced to mucosal or serosal tissue surfaces at a concentration similar to that used in vivo (10 microg/ml). ICG decreased Iscc by over 50% and gt by over 10%. Transepithelial mannitol flux was not altered. Dye was effective only from the serosal surface. Cyclic AMP-induced spiking of Iscc was not affected by ICG. Preincubation with amiloride or furosemide did not affect the action of the dye on gt or Iscc. ICG at in vivo dosages is clearly capable of inhibiting ion transport across colon epithelial tissue. The serosal site of action indicates activity on a basal-lateral transport system or diffusion into the cell only across the basal-lateral membrane followed by inhibition of a transporter from the intracellular side. ICG should not be considered inert in vivo. Leakage of ICG from the vascular space into the interstitial fluid space will likely result in tissue morbidity.