Influenza Pandemics: Past, Present and Future

Influenza A virus is well known for its capability for genetic changes either through antigen drift or antigen shift. Antigen shift is derived from reassortment of gene segments between viruses, and may result in an antigenically novel virus that is capable of causing a worldwide pandemic. As we trace backwards through the history of influenza pandemics, a repeating pattern can be observed, namely, a limited wave in the first year followed by global spread in the following year. In the 20th century alone, there were three overwhelming pandemics, in 1918, 1957 and 1968, caused by H1N1 (Spanish flu), H2N2 (Asian flu) and H3N2 (Hong Kong flu), respectively. In 1957 and 1968, excess mortality was noted in infants, the elderly and persons with chronic diseases, similar to what occurred during interpandemic periods. In 1918, there was one distinct peak of excess death in young adults aged between 20 and 40 years old; leukopenia and hemorrhage were prominent features. Acute pulmonary edema and hemorrhagic pneumonia contributed to rapidly lethal outcome in young adults. Autopsies disclosed multiple-organ involvement, including pericarditis, myocarditis, hepatitis and splenomegaly. These findings are, in part, consistent with clinical manifestations of human infection with avian influenza A H5N1 virus, in which reactive hemophagocytic syndrome was a characteristic pathologic finding that accounted for pancytopenia, abnormal liver function and multiple organ failure. All the elements of an impending pandemic are in place. Unless effective measures are implemented, we will likely observe a pandemic in the coming seasons. Host immune response plays a crucial role in disease caused by newly emerged influenza virus, such as the 1918 pandemic strain and the recent avian H5N1 strain. Sustained activation of lymphocytes and macrophages after infection results in massive cytokine response, thus leading to severe systemic inflammation. Further investigations into how the virus interacts with the host's immune system will be helpful in guiding future therapeutic strategies in facing influenza pandemics

Infections of Cefotaxime-Resistant and Cefmetazole-Susceptible Escherichia Coli and Klebsiella Pneumoniae in Children

A search of the computerized database at the National Taiwan University Hospital was made for cefotaxime-resistant and cefmetazole-susceptible isolates of Escherichia coli and Klebsiella pneumoniae (which may be extended-spectrum β- lactamase-producing strains) in pediatric wards and intensive care units between 1999 and 2001. Fourteen infectious episodes attributed only to study bacteria were identified, including 7 episodes of bacteremia. Nine patients (64.3%) had underlying medical conditions: 3 were premature babies, 3 were immunodeficient, 2 had malignancy, and 2 had a congenital heart disease with active heart failure even after surgery. Among the 7 patients with bacteremias, 5 may be catheter-related; 6 were treated with carbapenems and 1 was treated with cefmetazole successfully, with or without the removal of the catheter. Before the acquisition of the infection, a history of stay in an intensive care unit within 4 weeks was noted in 10 cases (71 .4%); a history of use of extended-spectrum cephalosporins within 4 weeks was also noted in 6 cases (42.9%). Cefmetazole, with or without an aminoglycoside, was clinically effective in 6 cases (42.8%). Except for 1 episode of pneumonia that ended in mortality, all of the infectious episodes were successfully treated. The mortality rate was 7.1%

A human papillomavirus public vaccination program in Taiwan: The Kinmen County experience

In Taiwan, cervical cancer is ranked sixth among all causes of death in women. With the goal of reducing the incidence of cervical cancer, the Kinmen County Health Bureau planned to implement a pilot human papillomavirus (HPV) vaccination program in 2007. The Bureau established a committee to promote public awareness, coordinate with the schools, arrange for the administration of the vaccine, establish a vaccination registry, and develop a plan for follow-up and assessment. Vaccination for female residents aged 16–18 began through a school-based program in 2008. A total of 1633 girls completed the vaccination protocol within 3 years, and vaccine uptake rates of over 90% were achieved by 2010. No serious adverse events were reported among those who were vaccinated. The experience gained from the Kinmen County HPV vaccination program has helped and will continue to help establish an operational model for similar programs throughout the country

Characteristics of the First Human Milk Bank in Taiwan

The benefits of feeding human milk to infants, even in prematurity, have been well documented. Well-organized donor milk processing has made the milk bank a good source of nutrition for premature or sick infants if their own mother's milk is not sufficient or suitable. The Taipei City Hospital Milk Bank was established in 2005 and is the first nonprofit human milk bank to operate in Taiwan. Methods: The milk bank has adopted standards of practice laid down by the Human Milk Banking Association of North America and United Kingdom Association for Milk Banking. The clinical characteristics of the eligible milk donors, the recipients, and the donor milk were reviewed retrospectively. Results: In the past 6 years, 816 eligible donors donated a total or 13,900 L (mean 17.03 L/donor) of breast milk. The mean age of these donors was 31.3 years, and 79.7% of them had college education. Most had term delivery (91.2%), with mean birth weight of their babies being 3120 g; 68.9% of the donors were primiparas. A total of 551 infants had received bank milk, with these indications: prematurity (65.4%), malabsorption (7.6%), feeding intolerance (7.2%), maternal illness (5.1%) and post-surgery (4.6%). The pass rate of raw donor milk was around 72.1%. The most common reasons to discard raw milk were Gram-negative rods contamination (72.8%) and ≥104 colony-forming units/mL of coagulase-negative Staphylococcus (62.3%). Only 0.63% of donor milk post pasteurization showed bacterial growth. Conclusion: Proper management and operation of a human milk bank can support breastfeeding, and provide a safe alternative to artificial formula for feeding preterm or ill infants in Taiwan. Sustainability of the milk bank needs more propagation and financial support by health authorities

Application of a bio-control agent for controlling strawberry anthracnose in Taiwan

Strawberry (Fragaria × ananassa Duchesne) is an economically important crop in Taiwan, however because of the outbreak of strawberry anthracnose in early 2010, the short supply of strawberry seedlings became a serious problem for strawberry production. The isolates of anthracnose causing organisms were collected from major strawberry cultivation areas in Miaoli County, and mainly identified as Colletotrichum siamense, these isolates were proved to be pathogenic to the leaves, crown and roots of strawberry. The bio-control agent of Bacillus amyloliquefaciens P-2-2, was isolated from rice paddy field and expressed effectively on inhibition of many fungal pathogens of strawberry. The strawberry seedlings used in this study were treated with 400-fold dilution of B. amyloliquefaciens P-2-2 fermentation broth once for every two weeks to protect the crown of the seedlings from anthracnose infection before transplanting. Sterilization of soil by biological soil disinfestation method was done during field preparation. After transplanted in the production field, the strawberry transplants were continuously treated with 400-fold dilution of B. amyloliquefaciens P-2-2 once for every two weeks until the end of the growing season. The results of field test, shown that the survival rate of the untreated group in demonstration area of Dahu Township was 83.9%, whereas the survival rate of seedlings treated with B. amyloliquefaciens P-2-2 increased to 95.1%. The replanting rate of strawberry in the untreated group area was 37.6%, compared to the B. amyloliquefaciens P-2-2 treated area which was reduced significantly to 10.7%. Upon those results indicated that application of bio-control agents with other practices were effective for controlling strawberry anthracnose

Influence of magnetoplasmonic γ-Fe2O3/Au core/shell nanoparticles on low-field nuclear magnetic resonance

Magnetoplasmonic nanoparticles, composed of a plasmonic layer and a magnetic core, have been widely shown as promising contrast agents for magnetic resonance imaging (MRI) applications. However, their application in low-field nuclear magnetic resonance (LFNMR) research remains scarce. Here we synthesised γ-Fe2O3/Au core/shell (γ-Fe2O3@Au) nanoparticles and subsequently used them in a homemade, high-Tc, superconducting quantum interference device (SQUID) LFNMR system. Remarkably, we found that both the proton spin-lattice relaxation time (T1) and proton spin-spin relaxation time (T2) were influenced by the presence of γ-Fe2O3@Au nanoparticles. Unlike the spin-spin relaxation rate (1/T2), the spin-lattice relaxation rate (1/T1) was found to be further enhanced upon exposing the γ-Fe2O3@Au nanoparticles to 532 nm light during NMR measurements. We showed that the photothermal effect of the plasmonic gold layer after absorbing light energy was responsible for the observed change in T1. This result reveals a promising method to actively control the contrast of T1 and T2 in low-field (LF) MRI applications

Rothia dentocariosa Bacteremia in Children: Report of Two Cases and Review of the Literature

Rothia dentocariosa, a pleomorphic, fastidious, Gram-positive rod, is a normal inhabitant of the oropharynx. It is a well-known causative agent of dental plaques and periodontal disease. Generally regarded as of low virulence to humans, R. dentocariosa has been increasingly recognized as a pathogen in adults and often associated with infective endocarditis. It should not necessarily be regarded as a contaminant when the isolate comes from areas other than the oropharynx, especially from the blood. We report two cases of R. dentocariosa bacteremia, including an 8-month-old boy with repaired transposition of the great arteries, and a healthy 20-month-old girl with herpangina. [J Formos Med Assoc 2007;106(3 Suppl): S33-S38

Laser-Scanned Programmable Color Temperature of Electroluminescence from White Light-Emitting Electrochemical Cells

Recently, the control of correlated color temperature (CCT) of artificial solid-state white-light sources starts to attract more attention since CTs affect human physiology and health profoundly. In this work, we proposed and demonstrated a method that can widely tune the CCTs of electroluminescence (EL) from white-light-emitting electrochemical cells (LECs) by employing plasmonic filters. These integrated on-chip plasmonic filters are composed of semicontinuous thin Ag film or Ag nanoparticles (NPs) both included in the indium tin oxide anode contact, which have different characteristics of plasmonic resonant absorptions that can tune the EL spectra of white LECs. The CCTs of EL from white LECs integrated with semicontinuous thin Ag film and randomly distributed Ag NPs are 5778 and 2350 K, respectively. A commercially available laser scanning system was used to locally thermal anneal the semicontinuous thin Ag film to form the randomly distributed Ag NPs on the scanned areas. Hence, these two kinds of filters can be integrated on the same chip of white LEC, giving more freedom to control the CCTs of white EL and more potential applications. In addition, the laser scanning system used here is quite often used in display manufactures so that our proposed method can be immediately adopted by the light-emitting diode industry