Xanthine oxidoreductase (XOR) catalyzes the conversion of hypoxanthine to xanthine and of xanthine to uric acid. Inhibitors of XOR block conversion of the oxypurines (hypoxanthine and xanthine) to uric acid, thus decreasing serum concentration of uric acid. Crystal structures of XOR- ibnhibitor complexes reveal that each inhibitor has different inhibition mechanisms, utilizing the enzyme structure and the reaction mechanism. Such variation of the inhibition mechanism affects in vivo hypouricemic effects of the inhibitors.

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Introduction: Splanchnic hypoperfusion is central to the pathogenesis of acute respiratory dysfunction syndrome (ARDS) and multiple organ dysfunction syndrome (MODS) after hemorrhagic shock (HS), which is a leading cause of morality in patients with severe trauma; however, the underlying mechanism remains unclear. The purpose of this study was to examine whether liposome-encapsulated hemoglobin (LEH) improves oxygen metabolism in rat small intestine after HS. Methods: HS was induced by withdrawing blood, and mean arterial pressure was maintained at 40 mmHg for 30 minutes. Rats were then resuscitated with shed blood+2 × shed blood volume in normal saline or LEH (equivalent volume to shed blood)+2 × shed blood volume in normal saline over 120 minutes. The small intestines were harvested at four different time points: before HS, after HS, and at 40 and 120 minutes of resuscitation. The tissue levels of lactate and alanine (μmol/g) were measured with ¹H magnetic resonance spectroscopy. Data are expressed as means ± SD and were compared by means of one-way analysis of variance followed by post hoc analysis using Fisher's protected least significant difference (n=5 in each group). Results: There was no significant difference in hemodynamics between the shed blood and LEH groups. Improvements in intestinal lactate and alanine levels with resuscitation were equivalent in between the shed blood and LEH groups. Conclusion: LEH appears to have a comparable oxygen carrying capacity to blood and may serve as a useful blood substitute.

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Sleep apnea syndrome (SAS) is defined as sleep disordered breathing (SDB) with at least five episodes of apnea or hypopnea per hour of sleep combined with symptoms of excessive daytime sleepiness. With prevalence of only 4% in men and 2% in women older than 30 years, SAS is not a rare disease and is increasing with the rate of obesity. It is thought that SAS is caused by narrowing of the upper respiratory tract due to enlargement of the surrounding soft tissue and the structures of the chin and face. Patients with SAS have many difficulties, such as excessive daytime sleepiness, a decline in daily activities, traffic accidents, hypertension, arrhythmia, and automatic nerve and endocrine system disorders. Consequently, SAS causes arteriosclerosis and final outcomes such as cardiovascular and cerebrovascular disease. Most patients with SAS are unaware of the severity of their disorder and seek medical attention only after a family member points out the snoring with apnea. It is important to remember that SAS is likely to trigger life-threatening disorders during sleep. Therefore, if symptoms, such as excessive sleepiness during daytime hours and snoring with apnea develop, a respiratory specialist should be consulted and continuous positive airway pressure therapy should be performed.

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A 45-year-old man was admitted to our hospital with left subcostal pain of sudden onset. Although this symptom had occurred frequently, no diagnosis had been established. An emergency chest roentgenogram suggested diaphragmatic hernia. Computed tomography and gastrography revealed Bochdalek hernia. It is important that diagnostic imaging be performed while symptoms are present in suspected cases of diaphragmatic hernia.

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Croup syndrome usually affects the larynx, trachea, and bronchi, and this inflammation of the upper air way produce typical symptoms: inspiratory stridor, hoarseness, and a barklike cough. The most common form, acute laryngotracheobronchitis, is caused by viral infection. Croup syndrome is of great importance in infants and small children, because a rare form, acute epiglottitis, is a medical emergency often requiring immediate treatment with an artificial air way. We report two cases of Croup syndrome.

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