Comparison of hyperbilirubinemia incidence between the newborns of zinc-taking and non-zinc-taking mothers during the third trimester of pregnancy.

BACKGROUND: Identification and control of the risk factors for hyperbilirubinemia can reduce the incidence and complications of this condition. Serum zinc level in newborns is reported to be one of the factors affecting the severity and incidence of neonatal hyperbilirubinemia. Therefore, the present study was conducted to compare hyperbilirubinemia incidence in neonates of zinc-taking and non-zinc-taking mothers. METHODS: In this observational study, we compared the incidence of hyperbilirubinemia during the first week of birth between newborns whose mothers had received zinc supplement during the third trimester of pregnancy (case group) with those whose mothers had not taken zinc supplement (control group). The checklist of newborns' conditions in both case and control groups was completed based on the obtained data regarding the infants, mothers, and laboratory findings. Data was analyzed using chi-squared test and t-test. RESULTS: The mean serum levels of zinc were 79.76±15 mg/dl and 70.93±15.67mg/dl in mothers who had received zinc during the third trimester and those who had not taken zinc supplement, respectively. The mean serum level of zinc in newborns who underwent phototherapy was 41.68±9.21 mg/dl, while it was 68.53±20.85 mg/dl in neonates who did not receive phototherapy. In addition, 36% of the neonates whose mothers had not received zinc required phototherapy, while only 11% of newborns whose mothers had taken zinc supplement received phototherapy. CONCLUSION: Zinc consumption during the third trimester of pregnancy increased the serum zinc level in both newborns and mothers and reduced the incidence and severity of idiopathic hyperbilirubinemia requiring treatment.

Investigating the effect of several factors on concentrations of bioaerosols in a well-ventilated hospital environment.

This study characterized and quantified the bacterial and fungal bioaerosols in nine wards of the Razavi Hospital (Mashhad, Iran) that is equipped with an advanced heating, ventilating, and air conditioning (HVAC) system including HEPA filters for air cleaning. In this study, 432 samples were taken from the indoor air of multiple hospital wards during the morning and afternoon shifts during summer and autumn. The particle number concentrations with sizes of > 0.3, > 0.5, > 1, > 2, > 5, and > 10 µm were measured using a 6-channel handheld particle counter. A greater diversity of bioaerosol types were observed during the morning shifts and during summer. The microbial load was not affected significantly by the temperature, relative humidity, working shift, season, and number of visitors, indicating the effectiveness of a well-designed ventilation system to eliminate site-specific variations. For microbial number concentrations, a significant correlation was only observed between the number of particles with a diameter of > 10 µm and the airborne microbial loading. Thus, passive sampling may not properly reflect the actual concentrations of smaller bioaerosols. In conclusion, HEPA filters in the HVAC system successfully decreased the bioaerosol concentrations in the hospital environment. Additionally, we recommend that active sampling be used in cases where a well-functioning HVAC system exists.