Epidemiology of neural tube defects and folic acid

This review article combines four disparate observations about Neural Tube Defects (NTDs). They are the worldwide decline in the birth incidence that began prior to prenatal diagnosis; family recurrence risks; the effect of prenatal diagnosis and termination of affected pregnancies; and the effect of folic acid

Solid Propellant Power Systems for Normal and Emergency Space Operations

The ability of man to function safely both inside and out of his spacecraft will become even more critical after his pioneering flights such as Gemini and Apollo are completed. As greater numbers of astronauts make flights of long duration, survival may well be a function of a number of extravehicular activities such as routine vehicle inspection, emergency maintenance and repair. erection of structures and platforms, and rescue operations. Current systems remain bulky, heavy, and a possible source of hazard and malfunction. The solid-propellant space power systems examined here are small, light, manually or automatically operated, and have the capability not only to propel and stabilize man in space, but provide a means of power to do an extremely wide variety of critical functions outside or within a spacecraft. It has often been stated that there is no need to replace a working system. The authors of this paper are in full agreement with this statement. Let us assume for purposes of illustration a simplified spacecraft which requires only two systems for its operation, one in the nose which is hydraulic, and another in the tail which is electrical. Both are well designed and completely workable. As long as they are capable of performing their required function and as long as they are capable of growth to meet additional mission requirements, there should be no valid reason to replace either by a solid-propellant hot gas system. But let us consider further. In the event of a failure of either system during a flight, the parts of one system cannot be used in a repair of the other. It would be very surpris - ing if the motors, switches, etc. of the electrical system could be substituted in any way for any of the valves and cylinders of the various hydraulic devices and vice versa. If, however, both systems were replaced with a compatible gas generator powered system, a failure in either end of the spacecraft could use parts and prime movers frorn the other. The present philosophy for space-borne systems and components imposes as criteria of design extremely high standards of operational reliability and there is no quarrel with this doctrine. However, high reliability from the standpoint of completion of a manned space mission ·does not necessarily imply complete maintenance- free reliability during the entire operating life of the various systems involved. We are dealing here with a vehicle containing a crew of thinking, random decision making, non-linear operating, human beings rather than an inanimate object which is capable of performing only the actions for which it has been pre-programmed. At the present time, crew members of space vehicles perform a variety of maintenance functions which enhance the operability of themselves and their vehicles. Such simple non-programmed act ions as tuning a radio or adjusting a thermostat can be considered as part of the maintenance functions. Bad communications? A pilot will naturally and instinctively tune his command receiver for increased performance or change to another communications channel where reception might be better. Too hot? A crew member turns down the thermostat on his suit a couple of notches to compensate for the extra heat load caused by unplanned exertion

A STAT-1 knockout mouse model for Machupo virus pathogenesis

<p>Abstract</p> <p>Background</p> <p>Machupo virus (MACV), a member of the <it>Arenaviridae</it>, causes Bolivian hemorrhagic fever, with ~20% lethality in humans. The pathogenesis of MACV infection is poorly understood, and there are no clinically proven treatments for disease. This is due, in part, to a paucity of small animal models for MACV infection in which to discover and explore candidate therapeutics.</p> <p>Methods</p> <p>Mice lacking signal transducer and activator of transcription 1 (STAT-1) were infected with MACV. Lethality, viral replication, metabolic changes, hematology, histopathology, and systemic cytokine expression were analyzed throughout the course of infection.</p> <p>Results</p> <p>We report here that STAT-1 knockout mice succumbed to MACV infection within 7-8 days, and presented some relevant clinical and histopathological manifestations of disease. Furthermore, the model was used to validate the efficacy of ribavirin in protection against infection.</p> <p>Conclusions</p> <p>The STAT-1 knockout mouse model can be a useful small animal model for drug testing and preliminary immunological analysis of lethal MACV infection.</p

Development of a New Vaccine for the Prevention of Lassa Fever

BACKGROUND: Recent importation of Lassa fever into Germany, the Netherlands, the United Kingdom, and the United States by travelers on commercial airlines from Africa underscores the public health challenge of emerging viruses. Currently, there are no licensed vaccines for Lassa fever, and no experimental vaccine has completely protected nonhuman primates against a lethal challenge. METHODS AND FINDINGS: We developed a replication-competent vaccine against Lassa virus based on attenuated recombinant vesicular stomatitis virus vectors expressing the Lassa viral glycoprotein. A single intramuscular vaccination of the Lassa vaccine elicited a protective immune response in nonhuman primates against a lethal Lassa virus challenge. Vaccine shedding was not detected in the monkeys, and none of the animals developed fever or other symptoms of illness associated with vaccination. The Lassa vaccine induced strong humoral and cellular immune responses in the four vaccinated and challenged monkeys. Despite a transient Lassa viremia in vaccinated animals 7 d after challenge, the vaccinated animals showed no evidence of clinical disease. In contrast, the two control animals developed severe symptoms including rashes, facial edema, and elevated liver enzymes, and ultimately succumbed to the Lassa infection. CONCLUSION: Our data suggest that the Lassa vaccine candidate based on recombinant vesicular stomatitis virus is safe and highly efficacious in a relevant animal model that faithfully reproduces human disease

The diagnosis and management of patients with idiopathic osteolysis

Idiopathic osteolysis or disappearing bone disease is a condition characterized by the spontaneous onset of rapid destruction and resorption of a single bone or multiple bones. Disappearing bone disorder is a disease of several diagnostic types. We are presenting three patients with osteolysis who have different underlying pathological features. Detailed phenotypic assessment, radiologic and CT scanning, and histological and genetic testing were the baseline diagnostic tools utilized for diagnosis of each osteolysis syndrome. The first patient was found to have Gorham-Stout syndrome (non-heritable). The complete destruction of pelvic bones associated with aggressive upward extension to adjacent bones (vertebral column and skull base) was notable and skeletal angiomatosis was detected. The second patient showed severe and aggressive non-hereditary multicentric osteolysis with bilateral destruction of the hip bones and the tarsal bones as well as a congenital unilateral solitary kidney and nephropathy. The third patient was phenotypically and genotypically compatible with Winchester syndrome resulting in multicentric osteolysis (autosomal recessive). Proven mutation of the (MMP2-Gen) was detected in this third patient that was associated with 3MCC deficiency (3-Methylcrontonyl CoA Carboxylase deficiency). The correct diagnoses in our 3 patients required the exclusion of malignant osteoclastic tumours, inflammatory disorders of bone, vascular disease, and neurogenic arthropathies using history, physical exam, and appropriate testing and imaging. This review demonstrates how to evaluate and treat these complex and difficult patients. Lastly, we described the various management procedures and treatments utilized for these patients

Inherited germline TP53 mutation encodes a protein with an aberrant C-terminal motif in a case of pediatric adrenocortical tumor

Childhood adrenocortical tumor (ACT), a very rare malignancy, has an annual worldwide incidence of about 0.3 per million children younger than 15 years. The association between inherited germline mutations of the TP53 gene and an increased predisposition to ACT was described in the context of the Li-Fraumeni syndrome. In fact, about two-thirds of children with ACT have a TP53 mutation. However, less than 10% of pediatric ACT cases occur in Li-Fraumeni syndrome, suggesting that inherited low-penetrance TP53 mutations play an important role in pediatric adrenal cortex tumorigenesis. We identified a novel inherited germline TP53 mutation affecting the acceptor splice site at intron 10 in a child with an ACT and no family history of cancer. The lack of family history of cancer and previous information about the carcinogenic potential of the mutation led us to further characterize it. Bioinformatics analysis showed that the non-natural and highly hydrophobic C-terminal segment of the frame-shifted mutant p53 protein may disrupt its tumor suppressor function by causing misfolding and aggregation. Our findings highlight the clinical and genetic counseling dilemmas that arise when an inherited TP53 mutation is found in a child with ACT without relatives with Li-Fraumeni-component tumors

Persistence of TEL-AML1 fusion gene as minimal residual disease has no additive prognostic value in CD 10 positive B-acute lymphoblastic leukemia: a FISH study

<p>Abstract</p> <p>Objectives </p> <p>We have analyzed t(12;21)(p13:q22) in an attempt to evaluate the frequency and prognostic significance of <it>TEL-AML1 </it>fusion gene in patients with childhood CD 10 positive B-ALL by fluorescence in situ hybridization (FISH). Also, we have monitored the prognostic value of this gene as a minimal residual disease (MRD).</p> <p>Methods</p> <p>All bone marrow samples of eighty patients diagnosed as CD 10 positive B-ALL in South Egypt Cancer Institute were evaluated by fluorescence in situ hybridization (FISH) for t(12;21) in newly diagnosed cases and after morphological complete remission as a minimal residual disease (MRD). We determined the prognostic significance of <it>TEL-AML1 </it>fusion represented by disease course and survival.</p> <p>Results</p> <p><it>TEL-AML1 </it>fusion gene was positive in (37.5%) in newly diagnosed patients. There was a significant correlation between <it>TEL-AML1 </it>fusion gene both at diagnosis (r = 0.5, P = 0.003) and as a MRD (r = 0.4, P = 0.01) with favorable course. Kaplan-Meier curve for the presence of <it>TEL-AML1 </it>fusion at the diagnosis was associated with a better probability of overall survival (OS); mean survival time was 47 ± 1 month, in contrast to 28 ± 5 month in its absence (P = 0.006). Also, the persistence at <it>TEL-AML1 </it>fusion as a MRD was not significantly associated with a better probability of OS; the mean survival time was 42 ± 2 months in the presence of MRD and it was 40 ± 1 months in its absence. So, persistence of <it>TEL-AML1 </it>fusion as a MRD had no additive prognostic value over its measurement at diagnosis in terms of predicting the probability of OS.</p> <p>Conclusion</p> <p>For most patients, the presence of <it>TEL-AML1 </it>fusion gene at diagnosis suggests a favorable prognosis. The present study suggests that persistence of <it>TEL-AML1 </it>fusion as MRD has no additive prognostic value.</p