EEG and Seizures in Children with Hemolytic–Uremic Syndrome

The EEG results of 11 children, ages 1-15 years, who presented with hemolytic-uremic syndrome complicated by seizures 3-10 days after the prodrome were studied. In four children who experienced generalized tonic-clonic seizures, the EEGs demonstrated diffuse delta slowing with no focality. All recovered without neurological deficit or a residual seizure disorder. Of seven children who experienced partial seizures, six had structural lesions on cranial computed tomography and residual focal neurological deficits with epilepsy. The EEGs in two patients revealed focal spikes and slowing consistent with the lateralization of the partial seizures, in four it was characterized by atypical "burst suppression," and in one showed epochs of high-amplitude delta slowing alternating with generalized suppression. Although episodic and generalized burst suppression is usually regarded as a grave prognostic indicator, all four subjects recovered.     

Inflammatory responses in blood samples of human immunodeficiency virus-infected patients with pulmonary infections

We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1beta (IL-1beta), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-alpha) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-alpha, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1beta, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-alpha levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5).     

A Community-based Study of Prolonged Fatigue and Chronic Fatigue

Previous estimates of the prevalence of fatigue and chronic fatigue have derived largely from treated populations and have been biased by differential access to health-care treatment linked with gender, racial/ethnic and social class status. This study involves a community-based prevalence study of prolonged fatigue and chronic fatigue. It addresses: (1) the rate of prolonged fatigue and chronic fatigue in a socioeconomically and ethnically diverse sample of 28,673 adults in Chicago; and (2) establishes the relative prevalence of prolonged fatigue and chronic fatigue across race/ethnicity, socio-economic status and gender. Univariate and multivariate statistical techniques were utilized to delineate the overall rate of prolonged fatigue and chronic fatigue in the Chicago population and its relative prevalence by gender, race/ethnicity, and social class. Findings indicated that fatigue is common in urban populations, but that prolonged fatigue and chronic fatigue occur in about 5.00 to 7.68 percent and 2.72 to 4.17 percent, respectively, of the sample of the population. Highest levels of fatigue were consistently found among women and those with lower levels of education and occupational status.     

Plasma homocysteine concentration and its relationship with the development of preeclampsia. Effect of prenatal administration of folic acid

The increase of plasmatic homocysteine (Hc) in pregnant women, who later develop preeclampsia/eclampsia, the cause of this increment and its pathogenic role in toxemia of pregnancy, are still controversial. The objectives of the present research were to determine the plasmatic He concentrations during the first and second trimesters of pregnancy and the effect of folic acid administration on these values, and in the prevention of preeclampsia. Ninety six pregnant women of low economic background were studied on the first prenatal consultation: 27 women in the first trimester of pregnancy and 59 in the second. After 8 hours of fasting, venous blood was extracted and each patient was provided with 1 mg folic acid tablets and instructed to ingest one tablet daily, and to come back to the laboratory after three months. Plasma homocysteine and serum folic acid were determined for each patient before and after the folic acid treatment, by using the IMX system (Abbott Lab) and radioimmunoassay, respectively. Basal homocysteine concentrations were 4.0 +/- 2.1 micromol/L and 4.8 +/- 2.1 micromol/L in the first and second trimesters respectively, with no significant modifications after three months of folic acid. Although the degree of desertion from the study was high, it was possible to determine the evolution of 65 pregnancies. Ten of them developed preeclampsia (15.4%). No significant differences were found in Hc concentrations, or the frequency of hyperhomocysteinemia in the different stages of pregnancy, between women with normal gestation and those who developed preeclampsia. The small sample size of these groups, preclude any valid conclusion, however the results do not suggest that Hc concentration or folic acid administration influence the development of toxemia of pregnancy.     

Mantle Cell Lymphomas Lack Expression of p27kip1, a Cyclin-Dependent Kinase Inhibitor

p27^Kip1 is a cyclin-dependent kinase inhibitor that regulates the decision to enter S phase or withdraw from the cell cycle. In resting cells, the level of p27^Kip1 provides an inhibitory threshold above which G1 cyclin D/E/cyclin-dependent kinases accumulate before activation; however, in cycling cells, p27^Kip1 protein is sequestered by high levels of active cyclin D/cyclin-dependent kinase 4 complexes. As a group, the cyclin-dependent kinase inhibitors have been proposed to act as tumor suppressor genes, and several members have been implicated in the pathogenesis of a variety of human cancers. We examined p27^Kip1 expression in 116 non-Hodgkin’s lymphomas including 50 cases of MCL (40 typical and 10 blastic variants), 21 follicular lymphomas, 20 diffuse large B-cell lymphomas, 16 chronic lymphocytic leukemias, 8 marginal zone B-cell lymphomas, and 1 splenic marginal zone lymphoma, and correlated its expression with that of the proliferation marker Ki67 (MiB1) and with p53. p27^Kip1gene structure was analyzed by Southern blot in the group of MCLs. In all cases of non-Hodgkin’s lymphoma other than MCL, p27^Kip1 expression was inversely related to the proliferation index as measured by Ki67. In contrast, in typical MCL, p27^Kip1 expression was negative in 35 of 40 (88%) cases, irrespective of the proliferative rate (median 15%; range 2 to 90%). Paradoxically, in the blastic variant of MCL, 8 of 10 (80%) cases showed expression of p27^Kip1, despite a high proliferation rate (median 60%; range 32 to 100%). However, the staining in most of the cases was less intense than in the reactive T lymphocytes. Deletions of p27^Kip1gene were not found in any of the 25 cases examined. p53 expression was found in 15 of 50 cases of MCL: 7 of 10 (70%) in the blastic variant and 8 of 40 (20%) in the typical MCL (70% vs. 20%, P < 0.0045). These results demonstrate that MCLs, in contrast to other non-Hodgkin’s lymphomas and normal lymphoid tissue, fail to correlate p27^Kip1 expression with the proliferation rate. This peculiar uncoupling of p27^Kip1 protein expression from the proliferation rate may be related to the high levels of cyclin D1 expressed in MCL and is likely to have profound effects on cell cycle regulation and contribute to the pathogenesis of MCL.     

Reduced ratio of protective versus proinflammatory cytokine responses to commensal bacteria in HLA-B27 transgenic rats

Germ-free HLA-B27 transgenic (TG) rats do not develop colitis, but colonization with specific pathogen-free (SPF) bacteria induces colitis accompanied by immune activation. To study host-dependent immune responses to commensal caecal bacteria we investigated cytokine profiles in mesenteric lymph node (MLN) cells from HLA-B27 TG versus nontransgenic (non-TG) littermates after in vitro stimulation with caecal bacterial lysates (CBL). Supernatants from CBL-stimulated unseparated T- or B- cell-depleted MLN cells from HLA-B27 TG and non-TG littermates were analysed for IFN-gamma, IL-12, TNF, IL-10 and TGF-beta production. Our results show that unfractionated TG MLN cells stimulated with CBL produced more IFN-gamma, IL-12 and TNF than did non-TG MLN cells. In contrast, CBL-stimulated non-TG MLN cells produced more IL-10 and TGF-beta. T cell depletion abolished IFN-gamma and decreased IL-12 production, but did not affect IL-10 and TGF-beta production. Conversely, neither IL-10 nor TGF-beta was produced in cultures of B cell-depleted MLN. In addition, CD4(+) T cells enriched from MLN of HLA-B27 TG but not from non-TG rats produced IFN-gamma when cocultured with CBL-pulsed antigen presenting cells from non-TG rats. Interestingly, IL-10 and TGF-beta, but not IFN-gamma, IL-12 and TNF were produced by MLN cells from germ-free TG rats. These results indicate that the colitis that develops in SPF HLA-B27 TG rats is accompanied by activation of IFN-gamma-producing CD4(+) T cells that respond to commensal bacteria. However, B cell cytokine production in response to components of commensal intestinal microorganisms occurs in the absence of intestinal inflammation.     

Phenotype delineation of ZNF462 related syndrome

Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features.     

Evaluation of formalin-inactivated Clostridium difficile vaccines administered by parenteral and mucosal routes of immunization in hamsters.

Clostridium difficile produces toxins that cause inflammation, necrosis, and fluid in the intestine and is the most important cause of nosocomial antibiotic-associated diarrhea and colitis. We evaluated C. difficile antigens as vaccines to protect against systemic and intestinal disease in a hamster model of clindamycin colitis. Formalin-inactivated culture filtrates from a highly toxigenic strain were administered by mucosal routes (intranasal, intragastric, and rectal) with cholera toxin as a mucosal adjuvant. A preparation of culture filtrate and killed whole cells was also tested rectally. The toxoid was also tested parenterally (subcutaneously and intraperitoneally) and by a combination of three intranasal immunizations followed by a combined intranasal-intraperitoneal boost. Serum antibodies against toxins A and B and whole-cell antigen were measured by enzyme-linked immunosorbent assay, neutralization of cytotoxic activity, and bacterial agglutination. The two rectal immunization regimens induced low antibody responses and protected only 20% of hamsters against death and 0% against diarrhea. The intragastric regimen induced high antibody responses but low protection, 40% against death and 0% against diarrhea. Hamsters immunized by the intranasal, intraperitoneal, and subcutaneous routes were 100% protected against death and partially protected (40, 40, and 20%, respectively) against diarrhea. Among the latter groups, intraperitoneally immunized animals had the highest serum anticytotoxic activity and the highest agglutinating antibody responses. Hamsters immunized intranasally and revaccinated intraperitoneally were 100% protected against both death and diarrhea. Protection against death and diarrhea correlated with antibody responses to all antigens tested. The results indicate that optimal protection against C. difficile disease can be achieved with combined parenteral and mucosal immunization.     

Pkd2 haploinsufficiency alters intracellular calcium regulation in vascular smooth muscle cells

Autosomal-dominant polycystic kidney disease is a multiorgan disease and its vascular manifestations are common and life-threatening. Despite this, little is known about their pathogenesis. Somatic mutations to the normal PKD allele in cystic epithelia and cyst development associated with the unstable Pkd2(WS25) allele suggest a two-hit model of cystogenesis. However, it is unclear if this model can account for the cardiovascular pathology or if haploinsufficiency alone is disease-associated. In the present study, we found a decreased polycystin-2 (PC2, protein encoded by Pkd2 gene) expression in Pkd2( +/-) vessels, roughly half the wild-type level, and an enhanced level of intracranial vascular abnormalities in Pkd2 (+/-) mice when induced to develop hypertension. Consistent with these observations, freshly dissociated Pkd2 (+/-) vascular smooth muscle cells have significantly altered intracellular Ca(2+) homeostasis. The resting [Ca(2+)](i) is 17.1% lower in Pkd2 (+/-) compared with wild-type cells (P=0.0003) and the total sarcoplasmic reticulum Ca(2+) store (emptied by caffeine plus thapsigargin) is decreased (P<0.0001). The store operated Ca(2+) (SOC) channel activity is also decreased in Pkd2 (+/-) cells (P=0.008). These results indicate that inactivation of just one Pkd2 allele is sufficient to significantly alter intracellular Ca(2+) homeostasis, and that PC2 is necessary to maintain normal SOC activity and the SR Ca(2+) store in VSMCs. Based on these findings, and the fact that [Ca(2+)](i) signaling is essential to the regulation of contraction, production and secretion of extracellular matrix, cellular proliferation and apoptosis, we propose that the abnormal intracellular Ca(2+) regulation associated with Pkd2 haploinsufficiency is directly related to the vascular phenotype.     

Epidermal growth factor receptor expression correlates with poor survival in gastric adenocarcinoma from Mexican patients: a multivariate analysis using a standardized immunohistochemical detection system.

The aim of the study was to determine epidermal growth factor receptor (EGFR) expression in gastric adenocarcinoma by standardized immunohistochemistry and to correlate EGFR expression with clinical features and patient survival. EGFR expression was investigated in paraffin sections of resection specimens of 89 gastric carcinomas from Mexican Mestizo patients using standardized immunohistochemistry with antigen retrieval (Dako EGFRpharmDx assay detection system). Membrane staining of EGFR was evaluated in the neoplastic cells and graded using a semiquantitative score (0-3+). Of the 89 carcinomas examined, staining of neoplastic cells was weak in 17 (19.1%, score 1+), moderate in 16 (18.0%, score 2+), and strong in nine cases (10.1%, score 3+). EGFR reactivity was heterogeneous, frequently showing completely negative up to 3+ positive areas within an individual tumor. EGFR reactivity score correlated with distant metastases (P=0.002) and clinical stage (P=0.033). EGFR score 0/1+ was significantly associated with an increase in patient survival when compared to score 2+/3+ (P=0.0006). In a multivariate analysis, EGFR positive cells in muscularis or subserosa (P=0.004), distant metastases (P=0.016) and residual disease (P=0.039) were significantly correlated with decreased survival. The prognosis was associated with the EGFR reactivity score (P=0.003), distant metastases (P=0.0001) and residual disease (P=0.012) in a univariate analysis. EGFR reactivity in neoplastic cells is an independent prognostic factor in gastric adenocarcinoma. The relevance of the heterogeneity in EGFR expression with regard to tumor progression, metastasis and anti-EGFR therapy needs to be studied.