Effects of Extreme Precipitation to the Distribution of Infectious Diseases in Taiwan, 1994–2008

The incidence of extreme precipitation has increased with the exacerbation of worldwide climate disruption. We hypothesize an association between precipitation and the distribution patterns that would affect the endemic burden of 8 infectious diseases in Taiwan, including water- and vector-borne infectious diseases. A database integrating daily precipitation and temperature, along with the infectious disease case registry for all 352 townships in the main island of Taiwan was analysed for the period from 1994 to 2008. Four precipitation levels, <130 mm, 130–200 mm, 200–350 mm and >350 mm, were categorized to represent quantitative differences, and their associations with each specific disease was investigated using the Generalized Additive Mixed Model and afterwards mapped on to the Geographical Information System. Daily precipitation levels were significantly correlated with all 8 mandatory-notified infectious diseases in Taiwan. For water-borne infections, extreme torrential precipitation (>350 mm/day) was found to result in the highest relative risk for bacillary dysentery and enterovirus infections when compared to ordinary rain (<130 mm/day). Yet, for vector-borne diseases, the relative risk of dengue fever and Japanese encephalitis increased with greater precipitation only up to 350 mm. Differential lag effects following precipitation were statistically associated with increased risk for contracting individual infectious diseases. This study’s findings can help health resource sector management better allocate medical resources and be better prepared to deal with infectious disease outbreaks following future extreme precipitation events

Effect of pressure and timing of contraction on human rib cage muscle fatigue

Breathing against inspiratory loads can be accomplished with different degrees of coupling between the diaphragm and the other muscles attached to the rib cage (RCM). Thus, the electromyographic signs of fatigue develop separately in each muscle group. While breathing with diaphragm emphasis, the occurrence of diaphragmatic fatigue was found to be related to the tension-time index TTdi (= Pdi/Pdimax x Ti/Ttot). Above the critical range of 0.15 to 0.18, the endurance of the diaphragm is less than 1 h and it is inversely related to the TTdi value. However, in most loaded breathing conditions, the spontaneous pattern of breathing is characterized by predominant activation of RCM. The tension-time conditions at which fatigue develops during breathing with RCM emphasis are not known. We assessed the critical tension-time value in four normal subjects breathing with RCM emphasis against inspiratory threshold loads. RCM predominance was achieved by developing negative abdominal pressure swings during inspiration, and it was characterized by the tension-time index TTrc (Ppl/Pplmax x Tl/Ttot), where Ppl is pleural pressure developed under this condition. Above a critical TTrc value of 0.30, endurance time was inversely related to TTrc, and it resulted from failure of the RCM rather than of the diaphragm. We conclude that the critical threshold, as assessed by TTrc, is higher for breathing patterns with RCM emphasis than previously described by TTdi for diaphragm emphasis. However, when predominantly recruited, as in breathing patterns commonly adopted in loaded conditions, the RCM fatigue earlier than the diaphragm

Increased neutrophil chemotactic activity in exercise- and "fog"-induced asthma

To investigate whether exercise- and ultrasonic "fog"-induced asthma are due to the same mechanism, i.e. mediator release induced by osmotic changes, we measured the serum neutrophil chemotactic activity before and after exercise and inhalation of "fog" in 15 asthmatic subjects. To assess changes in airway caliber we measured specific airway conductance (SGaw); to assess changes in neutrophil chemotactic activity we measured the maximum distance reached by neutrophils in a filter when challenged with the subject's serum in a Boyden chamber. In 10 subjects, SGaw decreased by more than 35% and neutrophil chemotactic activity increased significantly (P less than 0.05) both after exercise and "fog", whereas in five subjects no change occurred either after exercise or "fog". We conclude that both exercise- and "fog"-induced asthma are associated with increased serum neutrophil chemotactic activity, and that both stimuli may cause asthma by osmotically triggering mediator release from mast cells

Distribution of extracellular matrix proteins in pterygia: an immunohistochemical study

Naib-Majani W, Eltohami I, Wernert N, et al. Distribution of extracellular matrix proteins in pterygia: an immunohistochemical study. GRAEFES ARCHIVE FOR CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY. 2004;242(4):332-338.Purpose: This study was carried out to monitor the expression of extracellular matrix proteins (ECMs) and metalloproteinases (MMPs) in pterygial tissue. Methods: Twenty primary nasal pterygia were studied by indirect routine immunohistochemistry using 13 different primary antibodies against 8 ECMs (five collagens, fibronectin, heparan sulfate, and laminin) fibroblast growth factor (bFGF), von Willebrand factor (vWF), and 3 MMPs (8, 9, and 13). Secondary antibodies were fluoresceinated. Intensity of reaction on individual sections was graded semi-quantitatively. Results: No expression of collagens I, II, and VII was found. Antibodies against collagen III reacted strongly positively (+++) with the entire pterygial stroma. Collagen IV expression was strongly positive in the wall of pterygial blood vessels, moderately positive (++) in the epithelial basement membrane, and only weakly positive (+) all over the stroma. Antibodies against fibronectin reacted moderately positively with stroma, blood vessel walls and epithelial basement membrane. Heparan sulfate was strongly expressed in the blood vessel walls and epithelial basement membrane. Antibodies against bFGF reacted only with pterygial epithelium. Laminin was strongly expressed in blood vessel wall, moderately (++) in the epithelial basement membrane and weakly over the entire stroma. vWF was strongly positive (+++) with pterygial blood vessel walls. Antibody reactions for MMPs differed. It was strong with pterygial epithelium (MMPs 8, 9 and 13), strong to moderate with pterygial stroma (MMPs 8 and 13 versus 9), and absent to weak with pterygial vascular walls (MMPs 8 and 13 versus 9). Conclusions: This study documents the presence of several ECMs but excludes the expression of others in pterygial tissues. The results especially indicate an active involvement of MMPs 8, 9 and 13 in the pathogenesis of pterygia