Placental transfusion insult in the predisposition for SIDS: A mathematical study

A difference has been observed between the newborn hearing screening tests of thirty-one SIDS cases versus control infants that survived the first year of life [Rubens DD, Vohr BV, Tucker R, O'Neil CA, Chung W. Newborn oto-acoustic emission hearing screening tests. Preliminary evidence for a marker of susceptibility to SIDS. Early Hum Dev 2008;84(4);225-9]. This study is motivated by the hypothesis that the predisposition for SIDS may be caused by inner ear and brainstem damage from a high venous pressure insult at birth that disrupts an infant's ability to detect rising CO₂ levels following the first month of life. The injury is not immediately lethal due to the persistence of fetal physiological responses during the early postnatal period [Guntheroth WG. Crib death, the Sudden Infant Death Syndrome. Armonk NY: Futura Publishing Co.; 1995. p. 291]. Elastic vessels are assumed in the umbilical vein and newborn venous circulation at the time of a potential high pressure placental transfusion insult and pulse wave propagation is simulated using the nonlinear one-dimensional equations of blood flow in elastic vessels. Peak pressures in the auricular veins increase with the amplitude and length of the umbilical surge, reaching over 60 mm Hg when two consecutive surges separated by 100 ms, of a peak pressure of 100 mm Hg, and a pulse interval of 200 ms are propagated in a network with low peripheral reflections. Our findings support the proposed mechanism for inner ear damage in SIDS and the potential benefit of a newborn hearing screening test in identifying susceptibility and early preventative measures following birth.     

Primary transpupillary thermotherapy for small choroidal melanoma

Background  

The treatment of small choroidal melanoma is controversial. Thermal laser-induced treatment is utilized by some centers but there is still sparse literature about the subject, mainly with short-term follow-up time. The efficacy of transpupillary thermotherapy (TTT) for the treatment of small choroidal melanomas was evaluated.     

Successful plasma exchange combined with rituximab therapy in aggressive APS-related cutaneous necrosis

Antiphospholipid antibody syndrome (APS) is a systemic autoimmune disorder characterized by venous and/or arterial thrombosis or recurrent fetal loss associated with the presence of antiphospholipid antibodies and/or a lupus anticoagulant. The skin appears to be an important target organ and many cases of APS may present with skin manifestations. These lesions may be manifold and may take the form of livedo reticularis, livedo racemosa, ulcerations, digital gangrene, subungeal splinter hemorrhages, superficial venous thrombosis, thrombocytopenic purpura, pseudovasculitic manifestations, extensive cutaneous necrosis, or primary anetoderma. We report a case of fulminant APS-related cutaneous necrosis. A 38-year-old Caucasian male with a past history of APS, multiple deep vein thrombi/pulmonary emboli, presented with necrotic lesions on his right upper and right lower extremities. Initially, baseline anticoagulation was increased without improvement. Subsequently, plasma exchange was initiated on a daily schedule. Furthermore, rituximab 1,000 mg IV was administered on days 1 and 15. After six consecutive daily sessions of plasma exchange, there was significant regression of the necrotic lesions. After a 22-day hospital stay, the patient was discharged to home on fondaparinux. The patient presented approximately 2 months later after missing follow-up appointments. At the time, his initial lesions looked remarkably improved.

     

Isogenic group B streptococci devoid of capsular polysaccharide or beta-hemolysin: pulmonary hemodynamic and gas exchange effects during bacteremia in piglets

Group B beta-hemolytic streptococcus (GBS) causes thromboxane (Tx)-associated pulmonary hypertension and hypoxemia in neonatal animals and human infants. The components of GBS that induce these features of sepsis are incompletely characterized. The capsular polysaccharide has been implicated based on the effects of GBS extracts. We used isogenic mutants of a parent GBS strain (COH 31 r/s) devoid of capsular polysaccharide or beta-hemolysin to determine if these components caused the acute features of GBS bacteremia. In neonatal piglets, we observed a similar increase in pulmonary vascular resistance (PVR, mm Hg/L/min) during a 1 h infusion at 5 x 10(8) colony-forming unit/kg/h of COH 31 r/s (n = 5, 11.6 +/- 1.4 to 67.1 +/- 17.9), an isogenic GBS mutant devoid of type III CP (n = 5, 12.5 +/- 1.4 to 56.9 +/- 5.0), and an isogenic GBS mutant devoid of beta-hemolysin (n = 4, 11.0 +/- 1.9 to 51.9 +/- 7.9). All three GBS strains caused increases in blood TxB2 levels, mild arterial hypoxemia, mild reduction in mixed venous PO2, and a 30-40% reduction in cardiac output after a 1 h infusion. The Tx-synthase inhibitor, dazmegrel, completely reversed pulmonary hypertension, and partially reversed arterial hypoxemia and TxB2 levels to baseline values for all GBS strains. In six additional piglets, infusion of polystyrene beads of similar size to GBS at a dose of 5 x 10(8) beads/kg/h caused no changes in gas exchange or blood TxB2 levels, but a mild increase in PVR (13.3 +/- 2.0 to 17.7 +/- 3.5).(ABSTRACT TRUNCATED AT 250 WORDS)     

Muscoid dipterans as helminth eggs mechanical vectors at the zoological garden,Brazil

OBJECTIVE: To assess muscoid dipterae species who are able to carry helminth eggs and larvae and to evaluate the potential contamination of trapped dipterae. METHODS: The study was conducted in two different sites of the Zoological Garden of Rio de Janeiro from May 1996 to April 1998. Flies were captured weekly using traps containing putrefied fish, left out in the open for an hour at two sites in the zoo: Site 1 was next to the garbage and Site 2 was near the hippopotamus and birds of prey cages. Of the 41,080 flies captured, Chrysomya megacephala was the most representative species (69.34%), followed by Chrysomya albiceps (11.22%), Musca domestica (7.15%), Chrysomya putoria (4.52%), Fannia sp. ( 3.12%), Ophyra sp. ( 2.53%), and Atherigona orientalis (2.08%). Captured flies had their body surface washed out with distilled water and their gut dissected. RESULTS: Among the species studied, C. megacephala and M. domestica presented higher helminth eggs on their body surface and in their intestinal content. Ascaroidea and Trichinelloidea eggs prevailed in the intestinal content of C. megacephala. The helminth eggs found on the body surface and in the intestinal content were identified as Ascaris sp., Toxascaris sp., Toxocara sp., Trichuris sp., Capillaria sp., Oxyuridae, Trichostrongylidae and Acantocephala. Besides eggs it was also found helminth larvae on the body surface of flies. There were significant differences between the two different capture sites related to the number of helminth eggs found on the flies. CONCLUSIONS: Faeces of zoo animals frequently found in their cages and in the zoo garbage contributed to the proliferation of muscoid dipterans who play an important role in spreading helminth eggs, mainly by direct contact of the flies' body with the animals' food.     

Review of fexofenadine in the treatment of chronic idiopathic urticaria

Chronic idiopathic urticaria (CIU), characterized by the appearance of itchy wheals of unknown etiology, can be extremely debilitating and can significantly reduce a patient's quality of life (QOL). Fexofenadine, a non-sedating, H1-receptor selective, long-acting antihistamine, is licensed worldwide for the treatment of CIU. A number of dose-ranging studies have evaluated the efficacy and safety of fexofenadine for the the treatment of CIU. In two similar North American studies, patients received either fexofenadine HCI (20, 60, 120, or 240 mg bid) or placebo. All four doses of fexofendine were statistically superior to placebo at reducing pruritus and reducing the number of wheals (P < or = 0.0238). A dose-finding study undertaken in Japanese patients confirmed that fexofenadine HCI (60 mg and 120 mg bid) is an effective treatment for CIU. A similar dose response was shown in all three studies when the results were compared. Furthermore, health outcome analyses of the North American studies indicated that fexofenadine HCI 60 mg bid significantly improved patient's QOL. In these studies, fexofenadine had a consistently comparable safety profile to placebo, with no dose-related trends in the incidence of adverse events. In conclusion, fexofenadine is an effective and well-tolerated treatment for CIU, with a wide therapeutic window. Importantly, the lack of ethnic differences between the studies from North America and Asia indicate that the efficacy and safety of fexofenadine demonstrated in these studies are cross-culturally applicable.     

Seroprevalence of Helicobacter pylori infection in chronic chagasic patients,and in the rural and urban population from Uberlândia,Minas Gerais,Brazil

As patients with chronic Chagas disease exhibit morphological and functional changes of the stomach (hypomotility and hypochlorhydria), malnutrition, immunological deficiency and high prevalence of peptic disease associated to Helicobacter pylori infection, the purpose of this study was to evaluate if the prevalence of H. pylori infection in chronic chagasic is higher than in non-chagasic individuals in the urban and rural population from Uberlandia, MG, Brazil. Serological determination of IgG antibodies to H. pylori was performed using a second-generation ELISA. Thus, 598 people were evaluated: 128 chagasic (CG), 222 non-chagasic living in urban area (U-NCG) and 248 non-chagasic living in rural area (R-NCG). Regarding the age range from 21 to 50 years, the prevalence of H. pylori infection in the CG (85.1%) was significantly higher than in the U-NCG (56.3%, p < 0.01) and the R-NCG (67.4%, p < 0.05). In the patients over 50 years, the prevalence in the CG (86.4%) was similar to the U-NCG (78.8%) and R-NCG (86.1%). Similar results were also found between the U-NCG and R-NCG for all age ranges, with prevalence rates of 29.1% and 35.3% for the age range from 5 to 13 years, and 47.2% and 40% for that from 14 to 20 years, respectively. We conclude that chagasic patients showed a higher seroprevalence of H. pylori infection than non-chagasic individuals, in the age range from 21 to 50 years, and that the prevalence of this infection was similar in the studied urban and rural non-chagasic population.