Immunohistological study of grumose degeneration of the dentate nucleus in progressive supranuclear palsy

The grumose degeneration observed in the dentate nuclei of 7 cases of progressive supranuclear palsy (PSP) was studied with a panel of antibodies which included 2 neurofilaments, Tau and ubiquitin. Dentate nucleus neurons were negative with all antibodies except ubiquitin which showed a slightly positive homogeneous pattern of staining. The amorphous material surrounding swollen or normal neurons was strongly positive for neurofilament and subunits and numerous torpedoes were observed in the granular layer of the cerebellar cortex. Our results confirm that grumose degeneration consists in degeneration of terminal axons of Purkinje cells in the dentate nucleus. The positivity of dentate nucleus neurons for ubiquitin may support the concept of synaptic dysfunction between Purkinje cells and dentate nucleus neurons.     

Degradation of extracellular matrix proteins (fibronectin, vitronectin and laminin) by serine-proteinases isolated from Lonomia achelous caterpillar hemolymph.

Lonomia achelous is a caterpillar distributed in southern Venezuela and in northern Brazil that causes an acute hemorrhagic syndrome in people who have contact with its bristles. The effect of the crude hemolymph and its chromatographic fractions (FDII, Lonomin V and Lonomin V-2) on extracellular matrix proteins was studied. The chromatographic fractions show activities similar to plasmin and urokinase. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, both lonomins appear as a protein band of 25 kDa under reduced conditions. By exclusion chromatography, the molecular weights of Lonomin V and Lonomin V-2 were 26.5 and 24.5 kDa, respectively. Fibronectin, laminin and vitronectin were degraded by all venom components. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, under reduced conditions, shows that lonomins degrade fibronectin in four main fragments of 116, 60, 50 and 30 kDa. Molecular exclusion chromatography in native conditions shows that the molecular masses of these fragments are > or = 300, 62 and 27 kDa. The proteolytic effect of lonomins was abolished by benzamidine/HCl, iodoacetic acid and aprotinin. The extracellular matrix protein degradation together with the fibrino(geno)lytic activity of hemolymph and its fractions could explain, in part, the hemorrhagic syndrome, and the wound dehiscence in persons who have had contact with the L. achelous caterpillar.     

Loss of heterozygosity for distal markers on 22q in human gliomas.

Loss of constitutional heterozygosity as determined through the analysis of restriction-fragment-length polymorphism (RFLP) on tumoral and constitutional DNA has proven to be helpful to delimit the location of tumor-suppressor genes in the human genome. In malignant gliomas this approach indicates that chromosomes 9p, 10, 17p, and 22 may contain genes of this category involved in its origin and/or progression. Regarding chromosome 22, the data so far provided by molecular studies confirmed those previously reported by cytogenetic studies, suggesting the existence of a sub-group of malignant gliomas characterized by monosomy of this chromosome. However, the precise location of the putative glioma suppressor gene on chromosome 22 remains ambiguous. We have performed a combined cytogenetic and RFLP study on a series of 31 gliomas, looking for structural abnormalities of this chromosome. In 3 instances, terminal deletions of the long arm of chromosome 22 were observed by both methodologies, suggesting that the band q13 region distal to the D22S80 marker might be the critical domain non-randomly involved in tumor suppression of gliomas.     

Effect of intervention to improve breastfeeding technique on the frequency of exclusive breastfeeding and lactation-related problems.

This randomized clinical trial compared frequencies of exclusive breastfeeding and lactation-related problems during the first 30 days among 74 mothers who received a 30-minute counseling session on breastfeeding technique in the maternity ward, and 137 controls. The frequency of exclusive breastfeeding among mothers who had received intervention was similar to controls by 7 days (79.7% vs 82.5%, respectively) and 30 days (60.8% vs 53.3%). There was no difference between groups in the frequency of sore nipples at 7 and 30 days, in breast engorgement and mastitis, and in the quality of breastfeeding technique at 30 days. Therefore, a single intervention at maternity was not sufficient to improve breastfeeding technique, increase exclusive breastfeeding rates, and reduce the incidence of breastfeeding problems during the first month.     

Complications of the cardiopulmonary stress test in patients with depressed left ventricular systolic function.

BACKGROUND: The exercise test has a recognized lower risk of complications when used in the general population and in coronary artery diseased patients, but from a theoretical point of view should have a higher rate of complications when performed in patients with chronic heart failure (CHF). AIMS: To characterize and assess the type and incidence of complications during cardiopulmonary stress test (CPX) in patients with depressed left ventricular systolic function in comparison with a group of patients and individuals with normal function. METHODS: Retrospective analysis of the 334 consecutive CPX performed for risk stratification in 198 patients with a left ventricular ejection fraction below 40% (Group A) and 180 consecutive CPX performed in 78 subjects with normal function (Group B). The two groups were compared with respect to demographic data, CPX parameters and specific complications. Results: Major complications during the tests occurred only in 14 tests of Group A (4.2%, p = 0.012). Non-sustained ventricular tachycardia, <6 beats, occurred in 7 group A and 2 group B tests. The absence of coronary artery disease was the only independent predictor for complications. CONCLUSIONS: Major CPX complications occurred only in patients with impaired left ventricular systolic function. Heart failure patients showed a low probability (around 4%) for complications during CPX, significantly higher and more severe than the risk in the group of patients with normal ventricular function, allowing us to recommend that CPX in patients with heart failure should be performed in a hospital setting under the supervision of a physician with specific training.     

Determining the Alveolar Component of Nitric Oxide in Exhaled Air: Procedures and Reference Values for Healthy Persons

Nitric oxide (NO) production has been described using a 2-compartment model for the synthesis and movement of NO in both the alveoli and the airways. The alveolar concentration of NO (Ca_NO), an indirect marker of the inflammatory state of the distal portions of the lung, can be deduced through exhalation at multiple flow rates. Our objective was to determine reference values for Ca_NO. The fraction of exhaled NO (Fe_NO) was measured in 33 healthy individuals at a rate of 50 mL/s; the subjects then exhaled at 10, 30, 100, and 200 mL/s to calculate Ca_NO. A chemiluminescence analyzer (NIOX Aerocrine) was used to perform the measurements. The mean (SD) Fe_NO was 15 (6) ppb. The mean Ca_NO was 3.04 (1.30) ppb. These values of Ca_NO measured in healthy individuals will allow us to analyze alveolar inflammatory behavior in respiratory and systemic processes.     

Type 2 diabetes: assessment of endothelial lesion and fibrinolytic system markers.

This study aimed to investigate whether endothelial cells are damaged and to evaluate fibrinolytic system function in patients with type 2 diabetes. For this proposal, plasma levels of von Willebrand factor (an endothelial marker of injury), homocysteine (an inductor of endothelial injury), D-dimer (a marker of coagulation cascade activation) and plasminogen activator inhibitor-1 (a fibrinolysis marker) were measured in individuals with both type 2 diabetes and high blood pressure, with type 2 diabetes, with high blood pressure and in healthy control individuals. No significant differences among groups were observed for von Willebrand factor and homocysteine plasma levels. The type 2 diabetes and high blood pressure group presented a significant difference to the other groups for D-dimer and also presented high values for plasminogen activator inhibitor-1. The high blood pressure group and type 2 diabetes group presented separately higher values of plasminogen activator inhibitor-1 compared with the control group. High levels of D-dimer and plasminogen activator inhibitor-1 in patients with type 2 diabetes and high blood pressure with normoalbuminuria therefore indicate a state of hypercoagulability and hypofibrinolysis, despite no evident microvascular injury supported by normal levels of von Willebrand factor and homocysteine.     

Gender differences in condom-related behaviors and attitudes among Mexican adolescents living on the U.S.-Mexico border.

Adolescents are at increasing risk for HIV infection in Mexico. Research on gender differences in risk behaviors and determinants is needed to develop effective HIV prevention interventions targeting Mexican adolescents. This study examined gender differences in the likelihood of unprotected sex and theoretical correlates among high school students in the border city of Tijuana. Three hundred seventy high-school students completed a face-to-face interview and a self-administered survey. Differences in sexual initiation, condom use, intentions to use condoms in the future, and attitudes towards condoms in this population were assessed. Although male students initiated sexual practices earlier than females, females were more likely to have unprotected sex. Females perceived themselves as more likely to avoid unprotected sex in the future and held more favorable attitudes about condoms. The results suggest that stereotypical gender roles and communication barriers place Tijuana female high school students at higher risk for HIV infection than their male peers.     

Partial replication of a DRD4 association in ADHD individuals using a statistically derived quantitative trait for ADHD in a family-based association test.

BACKGROUND: Previous research found an association between single nucleotide polymorphisms (SNPs) in the promoter region of DRD4 and statistically derived phenotypes generated from attention-deficit/hyperactivity disorder (ADHD) symptoms. We sought to replicate this finding by using the same methodology in an independent sample of ADHD individuals. METHODS: Four SNPs were genotyped in and around DRD4 in 2631 individuals in 642 families. We developed a quantitative phenotype at each SNP by weighting nine inattentive and nine hyperactive-impulsive symptoms. The weights were selected to maximize the heritability at each SNP. Once a quantitative phenotype was generated at each SNP, the screening procedure implemented in PBAT was used to select and test the five SNPs/genetic model combinations with the greatest power to detect an association for DRD4. RESULTS: One of the four SNPs was associated with the quantitative phenotypes generated from the ADHD symptoms (corrected p-values = .02). A rank ordering of the correlation between each of the ADHD symptoms and the quantitative phenotype suggested that hyperactive-impulsive symptoms were more strongly correlated with the phenotype; however, including inattentive symptoms was necessary to achieve a significant result. CONCLUSIONS: This study partially replicated a previous finding by identifying an association between rs7124601 and a quantitative trait generated from ADHD symptoms. The rs7124601 is in linkage disequilibrium (LD) with the SNPs identified previously. In contrast to the previous study, this finding suggests that both hyperactive-impulsive and inattentive symptoms are important in the association.     

Incidence of Finding Residual Disease for Incidental Gallbladder Carcinoma: Implications for Re-resection

Re-resection for gallbladder carcinoma incidentally discovered after cholecystectomy is routinely advocated. However, the incidence of finding additional disease at the time of re-resection remains poorly defined. Between 1984 and 2006, 115 patients underwent re-resection at six major hepatobiliary centers for gallbladder carcinoma incidentally discovered during cholecystectomy. Data on clinicopathologic factors, operative details, TNM tumor stage, and outcome were collected and analyzed. Data on the incidence and location of residual/additional carcinoma discovered at the time of re-resection were also recorded. On pathologic analysis, T stage was T1 7.8%, T2 67.0%, and T3 25.2%. The median time from cholecystectomy to re-resection was 52 days. At the time of re-resection, hepatic surgery most often consisted of formal segmentectomy (64.9%). Patients underwent lymphadenectomy (LND) (50.5%) or LND + common bile duct resection (43.3%). The median number of lymph nodes harvested was 3 and did not differ between LND alone (n = 3) vs LND + common duct resection (n = 3) (P = 0.35). Pathology from the re-resection specimen noted residual/additional disease in 46.4% of patients. Of those patients staged as T1, T2, or T3, 0, 10.4, and 36.4%, respectively, had residual disease within the liver (P = 0.01). T stage was also associated with the risk of metastasis to locoregional lymph nodes (lymph node metastasis: T1 12.5%; T2 31.3%, T3 45.5%; P = 0.04). Cystic duct margin status predicted residual disease in the common bile duct (negative cystic duct, 4.3% vs positive cystic duct, 42.1%) (P = 0.01). Aggressive re-resection for incidental gallbladder carcinoma is warranted as the majority of patients have residual disease. Although common duct resection does not yield a greater lymph node count, it should be performed at the time of re-resection for patients with positive cystic duct margins because over one-third will have residual disease in the common bile duct. Presented at the 48th Annual Meeting of the Society for Surgery of the Alimentary Tract at Digestive Week 2007, Plenary Session, Washington, DC, March 23, 2007.