The role of heat shock protein 70 in the protective effect of YC-1 on heat stroke rats.

Heat stroke is a life-threatening illness characterized by an elevated core body temperature. Despite adequate lowering of the body temperature and support treatment of multiple organ-system function, heat stroke is often fatal. 3-(5'-Hydoxymethyl-2'-furyl)-1-benzyl-indazol (YC-1) been identified as an activator of soluble guanylate cyclase. To evaluate whether YC-1 protects multiple organ dysfunctions and improves survival during heat stroke and its mechanism. Male Sprague-Dawley rats untreated or treated with either YC-1 or quercetin (heat shock protein (Hsp) 70 inhibitor) were exposures to heat as a model of heat stroke. The mean arterial pressure (MAP), heart rate, rectal temperature (Tco), survival time, and plasma biochemical data, intracellular Hsp70 and heat shock factor-1 expression were measured. The value of MAP, heart rate and Tco of untreated heat stroke (HS) group were all significantly lower than that of normothermal (NT) group. Biochemical markers evidenced that liver and kidney injuries of HS group were significantly higher than that of NT groups. YC-1 (20mg/kg) pretreatment with heat stroke (YC-1+HS) group, the MAP and heart rate were return to normal, and the biochemical markers were all significantly recovered to normal. The survival time of HS group, NT group and YC-1+HS group were 21, 480, and 445 min, respectively. The expression of Hsp70 and HSF-1 in liver and renal of YC-1+HS group was significantly higher than that of HS group. All of the protective effects of YC-1 were all significantly suppressed when pretreated with quercetin (400mg/kg). Results indicate that YC-1 may improve survival due to induce Hsp70 overexpression.

The role of receptor-interacting protein 140 in the accumulation of fat in ovariectomised rats.

BACKGROUND: Receptor-interacting protein 140 (RIP140) is a corepressor for nuclear receptors with an important role in the inhibition of energy expenditure. Postmenopausal women have increased white adipose tissue (WAT), and excessive accumulation of adipose tissue (obesity) implies a health risk. The aim of the present work was to investigate the time course of RIP140 expression in WAT during the development of ovariectomy (OVX)-induced obesity in rats. METHODS: OVX was performed in female Sprague-Dawley (SD) rats 8 weeks old. Body weight and food intake were determined once a week. WAT of sham-operated, OVX and OVX plus 17ß-estradiol therapy (OVX/E2) female SD rats was weighed and used to analyse RIP140 and uncoupling protein 1 (UCP-1) expression by Western blot. RESULTS: Food intake and body weight were significantly increased during the 2-8 weeks after OVX. Even though body weight increased until killing, food intake progressively decreased from 9 to 16 weeks after OVX in rats. Meanwhile, increased WAT mass and decreased RIP140 expression in WAT were observed in OVX rats. In contrast, the expression of UCP-1, a key target gene of RIP140, in WAT of OVX rats was significantly higher than in sham-operated rats. All of these alterations caused by OVX were mostly reversed by the replacement of 17ß-estradiol. CONCLUSIONS: The down-regulation of RIP140 in WAT may play a compensatory role in OVX-induced obesity in rat.

Management of patent ductus arteriosus in term or near-term neonates with respiratory distress.

BACKGROUND: Respiratory distress and patent ductus arteriosus (PDA) in neonates are mutually perpetuating. Contrary to the situation in premature infants, the recognition, clinical relevance and optimal management of PDA in full-term neonates are unclear. The present study aimed to identify PDA as a possible cause of respiratory distress in term and near-term neonates, and to examine the clinical responsiveness of PDA to different treatment modalities in mature-gestational-age neonates. METHODS: Patients with gestational ages of over 34 weeks were included in this retrospective chart review; they had PDA as the sole recognizable cause of respiratory distress and were free of all other diseases. Clinical responsiveness to different regimens, including conservative treatment, drug therapy with preload reduction and inotropic agent with or without the addition of indomethacin, and surgical intervention were analyzed. RESULTS: Forty-four neonates qualified for this study. Six received no treatment and their cardiorespiratory symptoms resolved within 1 week (regimen A). Symptoms in 11 neonates were relieved after use of diuretic and inotropic agents (regimen B). Twelve neonates became asymptomatic without further intervention after indomethacin treatment in addition to preload reduction and inotropes (regimen C). A total of 15 of the 44 infants underwent PDA ligation (regimen D) due to persistent heart failure following regimens B or C, but had speedy resolution of respiratory symptoms following surgery. There were significant differences in birth body weight and hemodynamic variation based on left atrium to aortic root dimensional ratio between the treatment (regimens B, C and D) and non-treatment (regimen A) groups (p < 0.05). CONCLUSION: PDA plays an important role in prolonging respiratory distress in term or near-term neonates. Although most infants respond to noninvasive medical treatment, surgical ligation during the neonatal period is warranted in certain mature infants. Surgical treatment should be considered in patients with smaller birth body weights and those with increased left atrium to aortic root dimensional ratios.

Recurrent neonatal group B streptococcal disease associated with infected breast milk.

Group B streptococcus (GBS) is a major cause of severe systemic infections among the newborn. Both recurrent and maternal mastitis-associated, group B streptococcus diseases are uncommon. Persistence of GBS colonization of infants' mucous membrane is postulated to influence the pathogeneses of recurrent GBS infection. The authors describe a term infant who was treated for GBS sepsis and meningitis and then later developed recurrent GBS sepsis, without meningitis, due to feeding of infected breast milk. Randomly amplified polymorphic DNA polymerase chain reaction assay was performed to demonstrate that the GBS isolates from the first and second episode of infection and the maternal milk are identical. The authors conclude that transmission of GBS through breast milk should be considered in cases of recurrent neonatal GBS infection and bacterial culture of breast milk should be routinely performed in such cases.

Surgical closure of patent ductus arteriosus in preterm infants at neonatal intensive care unit.

Between January 1997 and June 2002, we retrospectively reviewed the records of all premature infants (birth weight less than 2000 g) admitted to the newborn intensive care unit (NICU) at Chi Mei Medical Center. Among the 399 premature infants (birth weight less than 2000 g) surviving more than one week, 111 infants were diagnosed with patent ductus arteriosus (PDA). Seventeen premature infants underwent surgical closure of PDA after failure of indomethacin treatment. The indication for surgical closure of PDA was ventilator dependence and/or congestive heart failure in infants with echocardiographic evidence of a ductus arteriosus. The mean gestational age and birth weight were 26.9 +/- 2.4 weeks (range 23-32 weeks) and 978.8 +/- 360.1 g (range 494-1920 g), respectively. The mean age and weight at the time of operation were 28.1 +/- 12.4 days (range 13-61 days) and 950.8 +/- 390.4 g (range 402-2120 g), respectively. All the operation procedures were performed in our NICU, using operating room personnel, thus eliminating the risks of patient transport. There was no intraoperative death. Three infants died in hospital due to other problems. One died of sepsis and the other two died due to bronchopulmonary dysplasia (BPD) and suspected sepsis. There were only two infants who had complications after surgical closure of PDA. One infant had left pneumothorax with subcutaneous emphysema and the other one had right upper lung collapse. We conclude that surgical closure of the PDA for the premature infant can be a safe and effective procedure performed in the NICU, when indomethacin closure is ineffective or contraindicated.