Synthesis of Quillaic Acid through Sustainable C-H Bond Activations.

To meet the demand for quillaic acid, a multigram synthesis of quillaic acid was accomplished in 14 steps, starting from oleanolic acid, leading to an overall yield of 3.4%. Key features include C-H activation at C-16 and C-23. Through Pd-catalyzed C-H acetoxylation, the oxidation at C-23 was observed as the major product, as opposed to at C-24. A copper-mediated C-H hydroxylation using O2 successfully afforded the single isomer, 16ß-ol triterpenoid, followed by configuration inversion to the desired 16α-ol compound. In summary, with steps optimized and conducted on a multigram scale, quillaic acid could be feasibly acquired through C-H activation with inexpensive copper catalysts, promoting a more sustainable approach.

Sodium Glycerophosphate Use in Parenteral Nutrition Improves Mineral Metabolism in Extremely Low Birth Weight Infants.

OBJECTIVE: To evaluate the clinical effect of sodium glycerophosphate (NaGP) in parenteral nutrition solutions on mineral metabolism in extremely low birth weight (ELBW) infants. STUDY DESIGN: NaGP was introduced for use in place of potassium phosphate (K3PO4) in January 2018; this retrospective cohort study included 95 ELBW infants treated with K3PO4 between January 2015 and December 2017 and 77 infants treated with NaGP between August 2018 and January 2021. Mineral intake over the first 14 days; changes in serum calcium, phosphorus, sodium, and alkaline phosphatase (ALP) levels over the first 1-3 months; and the rates of electrolyte imbalance and clinical morbidity were compared. High-risk infants who had nil per os (NPO) status for >14 days and prolonged parenteral nutrition exposure were further analyzed as a subgroup. RESULTS: The use of NaGP instead of K3PO4 significantly increased Ca and P intake, but intakes remained below the recommended range (Ca, 64-140 mg/kg/day; P, 50-108 mg/kg/day). Compared with levels in the K3PO4 group, the NaGP group had significantly higher serum Ca and P levels after day 14 and lower ALP levels after day 56. In the subgroup analysis, the NaGP group had significantly lower incidences of hypophosphatemia, hyponatremia, bronchopulmonary dysplasia, and ALP >500 IU/L. CONCLUSIONS: Although the administration of NaGP instead of K3PO4 in parenteral nutrition regimens still did not provide adequate Ca and P intake for ELBW infants, higher intake significantly improved serum Ca and P levels, especially in ELBW infants with prolonged parenteral nutrition exposure.

Microrna-486-5P Regulates Human Pulmonary Artery Smooth Muscle Cell Migration via Endothelin-1.

Pulmonary arterial hypertension (PAH) is a fatal or life-threatening disorder characterized by elevated pulmonary arterial pressure and pulmonary vascular resistance. Abnormal vascular remodeling, including the proliferation and phenotypic modulation of pulmonary artery smooth muscle cells (PASMCs), represents the most critical pathological change during PAH development. Previous studies showed that miR-486 could reduce apoptosis in different cells; however, the role of miR-486 in PAH development or HPASMC proliferation and migration remains unclear. After 6 h of hypoxia treatment, miR-486-5p was significantly upregulated in HPASMCs. We found that miR-486-5p could upregulate the expression and secretion of ET-1. Furthermore, transfection with a miR-486-5p mimic could induce HPASMC proliferation and migration. We also found that miRNA-486-5p could downregulate the expression of SMAD2 and the phosphorylation of SMAD3. According to previous studies, the loss of SMAD3 may play an important role in miRNA-486-5p-induced HPASMC proliferation. Although the role of miRNA-486-5p in PAH in in vivo models still requires further investigation and confirmation, our findings show the potential roles and effects of miR-486-5p during PAH development.

Reducing intraventricular hemorrhage following the implementation of a prevention bundle for neonatal hypothermia.

INTRODUCTION: In very low birth weight (VLBW) infants, hypothermia immediately following birth is common even in countries rich in medical resources. The purpose of this study is to design a standard prevention bundle that decreases the rate of hypothermia among infants after birth and to investigate efficacy of the bundle and short-term outcomes for VLBW infants. METHODS: This quality improvement project was conducted from February 2017 to July 2018 on all VLBW preterm infants admitted at a single referral level III neonatal intensive care unit. The infants were classified into the pre-intervention (February to September 2017) and post-intervention (October 2017 to July 2018) groups according to the time periods when they were recruited. During the pre-intervention period, we analyzed the primary causes of hypothermia, developed solutions corresponding to each cause, integrated all solutions into a prevention bundle, and applied the bundle during the post-intervention period. Afterwards, the incidence of neonatal hypothermia and short-term outcomes, such as intraventricular hemorrhage (IVH), acidosis, and shock requiring inotropic agents, in each group were compared. RESULTS: A total of 95 VLBW infants were enrolled in the study, including 37 pre-intervention, and 58 post-intervention cases. The incidence of hypothermia in preterm infants decreased significantly upon the implementation of our prevention bundle, both in the delivery room (from 45.9% to 8.6%) and on admission (59.5% to 15.5%). In addition, the short-term outcomes of VLBW infants improved significantly, especially with the decreased incidence of IVH (from 21.6% to 5.2%, P = 0.015). CONCLUSIONS: Our standardized prevention bundle for preventing hypothermia in VLBW infants is effective and decreased the IVH rate in VLBW infants. We strongly believe that this prevention bundle is a simple, low-cost, replicable, and effective tool that hospitals can adopt to improve VLBW infant outcomes.

Intravitreal Bevacizumab Is Associated With Prolonged Ventilatory Support in Preterm Infants With Bronchopulmonary Dysplasia.

BACKGROUND: Intravitreal bevacizumab (IVB), an anti-vascular endothelial growth factor (VEGF) antibody, is a widely adopted treatment for retinopathy of prematurity (ROP). Although animal studies have demonstrated that IVB inhibits alveologenesis in neonatal rat lung, the clinical influence of IVB on respiratory outcomes has not been studied. RESEARCH QUESTION: Does IVB affect the respiratory outcome in preterm infants with bronchopulmonary dysplasia? STUDY DESIGN AND METHODS: We retrospectively assessed very low birth weight (VLBW) preterm infants admitted to our neonatal ICU between January 2016 and June 2021. Furthermore, we evaluated the short-term respiratory outcomes after IVB therapy in VLBW preterm infants requiring ventilatory support at 36 weeks' postmenstrual age (PMA). RESULTS: One hundred seventy-four VLBW preterm infants with bronchopulmonary dysplasia were recruited. Eighty-eight infants showed ROP onset before being ventilator free, and 78 infants received a diagnosis of the most severe ROP before being ventilator free. Among them, 32 received a diagnosis with type 1 ROP and received IVB treatment. After adjusting for gestational age, birth body weight, and baseline respiratory status, we discovered that IVB is associated significantly with prolonged ventilatory support and a lower likelihood of becoming ventilator free (hazard ratio, 0.53; P = .03). INTERPRETATION: IVB may have a short-term respiratory adverse effect in patients requiring ventilatory support at 36 weeks' PMA. Therefore, long-term follow-up for respiratory outcomes may be considered in VLBW infants who receive IVB treatment.

Specific Premature Groups Have Better Benefits When Treating Apnea With Caffeine Than Aminophylline/Theophylline.

Background: Methylxanthines (caffeine; aminophylline/theophylline) are commonly used for apnea of prematurity (AOP) treatment. We aimed to compare the efficacy and adverse effects of caffeine and aminophylline/theophylline. Methods: A retrospective case-control gestational age-matched study investigates patients born between January 2017 and December 2018, 23-35 weeks gestation with birth weights >500 g treating AOP with caffeine or aminophylline/theophylline. Results: There were 144 cases (48 in caffeine group and 96 in aminophylline/theophylline group). The median treatment durations were 11 and 17 days in caffeine and aminophylline/theophyllinegroup (p = 0.002). When tachycardia is defined as heart rate ≥160 bpm, the rates were 8.3 and 34.4% in caffeine and control group (p = 0.001). When tachycardia is defined as 10 bpm over baseline heart rate, the rates were 41.7 and 63.5% in caffeine and aminophylline/theophylline group (p = 0.01). Stratified by gestational age and sex, significant reductions in tachycardia rates with caffeine than with theophylline were limited to male infants and infants born at <30 weeks gestation. Conclusions: For apnea treatment, caffeine has greater efficacy and fewer tachycardia than aminophylline/theophylline, especially in male infants and infants born at <30 weeks gestation.

Evaluating photoneutron dose equivalents for lung cancer using PMMA phantoms undergoing 15 MV IMRT.

BACKGROUND: According to statistics of the Ministry of Health and Welfare in 2017, the second leading cause of death in Taiwan was lung cancer. OBJECTIVE: Routine treatment planning does not consider photoneutron dose equivalent (PNDE) of patient induced secondary radiation resulting from primary exposure of lung cancer. However, such treatment is potentially important for improving estimates of health risks. METHODS: This study used 10, 30, 50, 70, and 90 kg of polymethylmethacrylate (PMMA) phantoms as patient to measure PNDE varying anatomical area during lung cancer of intensity modulated radiotherapy (IMRT) treatment. Paired thermoluminescent dosimeters (TLD-600 and 700) were calibrated using university reactor neutrons. TLDs were inserted into phantom which was closely corresponded of the represented tissues or organs. RESULTS: Neutron doses (ND) of organ or tissue (N⁢DT) were determined in these phantoms using paired TLDs approach. The risks of incurring fatal secondary malignancies, maximum statistical and total errors were estimated. Evaluated PNDE ranged from 0.80 ± 0.12 to 0.56 ± 0.08 mSv/Gy for these phantoms. CONCLUSION: The estimated N⁢DT decreased with increasing distance that is from the central axis. Evaluated PNDE and N⁢D𝑠𝑘𝑖𝑛 for these phantoms were discussed. This investigation also identified secondary risks associated with PNDE relating to radiation protection.

Evaluating dose distributions of normal organs for patients undergoing VMAT therapy of nasopharyngeal carcinoma using Rando phantom and TLD-100H.

BACKGROUND: The routine radiation therapy treatment planning does not include secondary radiation and peripheral doses resulting from radiotherapy exposure in patients with nasopharyngeal carcinoma (NPC) undergoing Volumetric Modulated Arc Therapy (VMAT) using an linear accelerator (linac) of Axesse (Elekta 2538). OBJECTIVE: VMAT has a better dose conformity of the tumor and is also operated by adjusting the shapes of mulileaf collimator. However, such treatment is potentially important to improve the accuracy of estimated health risks. METHODS: This study aimed to evaluate the equivalent dose of organ or tissue (DT) and effective dose (E) for normal organs using the Alderson Rando phantom as an equivalent of the human body. Thermoluminescent dosimeters (TLD-100H) were calibrated by 6 MV X-ray originated by the linac. A total of 252 TLDs were used. These TLDs were inserted into phantom organ or tissue which closely approximated to these places. RESULTS: The thyroid dose (D𝑡ℎ𝑦) had the highest dose, 1840 ± 202 mSv/treatment. The E of the Rando was 7.11 ± 0.61 mSv/treatment, as estimated using ICRP 103. The skin doses (D𝑠𝑘𝑖𝑛) varied significantly outside the treatment field and decreased as the distance from the treatment field increased. CONCLUSIONS: This study can be referred to practical guidance regarding radiation protections of the public.

Evaluating environmental radiations of the tomotherapy facility by optimizing full factorial design of the TLD technique.

BACKGROUND: In the last 40 years, the number of deaths due to cancer has been the highest in TaiwanOBJECTIVE: To optimize the readout system of the thermoluminescent dosimeter (TLD)-100H, the radiation rates among the Tomotherapy (TOMO) facility of the Department of Radiology Oncology of Chung Shan Medical University Hospital (CSMUH) were calculated with a 32 full factorial design (FFD). METHODS: A ten-month survey of the facility was employed using the sensitive and accurate TLD method. The TLD system was optimized for maximum temperature, heat rate, and preheat temperature of Harshaw 3500 reader. Eight analyzed groups with different factors were tested. RESULTS: The TOMO facility had significantly different radiation rates. The farther away from the gantry head, environmental radiation rates. The half value layer (HVL) was also determined. These results were compared with published. No significant contributions of environmental gamma radiations were detected except in the treatment room. CONCLUSIONS: Those were far below the occupational doses recommended by ICRP 60.

Validation of the Postnatal Growth and Retinopathy of Prematurity Screening Criteria in a Taiwanese Cohort.

PURPOSE: To validate the performance of Postnatal Growth and Retinopathy of Prematurity (G-ROP) screening criteria in a Taiwanese cohort. DESIGN: Screening evaluation with retrospective data. METHOD: Premature infants who underwent retinopathy of prematurity (ROP) screening between January 2015 and April 2019 at a tertiary hospital were examined. Infants with known final ROP results and complete longitudinal weight records were included. G-ROP screening criteria, both original and simplified (G-ROP 180 g), were applied as the prediction model for type 1 ROP; sensitivity and specificity were analyzed. The reduction in the number of infants requiring ROP screening and the number of funduscopic examinations were calculated. RESULT: A total of 303 infants with documented ROP outcomes and complete weight gain records were examined. Of these, 103 infants developed ROP, of whom 29 developed type 1 ROP, whereas the other 200 did not develop ROP. For the detection of type 1 ROP, the sensitivity and specificity of the original G-ROP screening criteria were 96.6% and 42.3%, and 100% and 31%, for the simplified G-ROP 180 g model, respectively. The reduction in the number of infants requiring screening and funduscopic examinations was 32.6% and 33.5% for the original G-ROP criteria, and 28.1% and 23.2% for the G-ROP 180 g model, respectively. CONCLUSION: Both the original G-ROP and G-ROP 180 g criteria attained high sensitivities in detecting type 1 ROP in the current Taiwanese cohort, with the G-ROP 180-g model outperforming the original one. Validation and modification may be required before applying G-ROP screening criteria to different populations.

Propolis alleviates 4-aminobiphenyl-induced oxidative DNA damage by inhibition of CYP2E1 expression in human liver cells.

4-Aminobiphenyl (4-ABP) may cause DNA damage in human liver cells (HepG2 and L-02). Propolis exhibits antioxidant properties through reactive oxygen species (ROS) scavenging. We determined the effects of propolis in alleviating 4-ABP -induced DNA damage using the comet assay. Results revealed that propolis could significantly alleviated oxidative damaged DNA by 4-ABP. Furthermore, we proved that inhibition of cytochrome P450 2E1 (CYP2E1) expression by propolis could contribute to the decreased oxidative DNA damage in the treated cells, as the conversion of 4-ABP into its metabolite, N-hydroxy-ABP (HOABP), was blocked; after all, HOABP showed more genotoxic than its parent chemical, 4-ABP. With the homologous recombination assay, propolis failed to induce DNA repair enzymes. Furthermore, the expression of RAD51, Ku70/Ku80, and OGG1 in treated cells were determined with the western blot, revealing that the expression of these protein were unchanged in comparison with those in nontreated cells. However, propolis could protect the treated cells from DNA damage. In conclusion, propolis could antagonize 4-ABP-induced oxidative DNA damage though the removal of ROS and inhibition of CYP2E1 expression in the treated cells.

Association between short-term exposure to air pollution and sudden infant death syndrome.

The association between air pollution and infant mortality has been inconsistently reported. A few studies have estimated short-term effects of air pollution on infants' health. This population-based case-control study aimed to examine the potential effects of air pollution on sudden infant death syndrome (SIDS) in the post-neonatal period in Taiwan during 1997-2002. Each case of infant death was matched with 20 randomly selected sex-matched controls who were born on the same day and were still alive. We obtained 24-h measurements of air pollutants and meteorological factors in each case and control with 1- to 14-day lags from 55 air-quality monitoring stations. After controlling for potential confounders, conditional logistic regression analysis was performed to estimate effects of air pollutants on SIDS (n = 398) and respiratory death (n = 121) among neonates. In single- and multi-pollutant models, we found that 100-ppb increment in carbon monoxide (Odds Ratio = 1.04-1.07) and 10-ppb increment in nitrogen dioxide (Odds Ratio = 1.20-1.35) with 1- to 14-day lags were associated with significant increase in SIDS, although a significant relationship between air pollution and respiratory death was not determined in 1- to 14-day lags. Short-term carbon monoxide and nitrogen dioxide exposure were associated with significant increase in SIDS in the post-neonatal period, with latency estimated within days before death.

Hypophosphatemia as an Early Metabolic Bone Disease Marker in Extremely Low-Birth-Weight Infants After Prolonged Parenteral Nutrition Exposure.

BACKGROUND: Early metabolic bone disease (MBD) detection is important in preterm infants to decrease long-term consequence. We aim to explore the early MBD biochemical marker in extremely low-birth-weight (ELBW) infants. METHODS: Retrospective cohort study of 95 preterm infants born in a tertiary care-level neonatal intensive care unit between January 2015 and June 2018, with birth weight <1000 g. Thirty-five infants were "nothing by mouth" for >14 days and categorized as the high-risk group; the remaining 60 were categorized as the control group. Mineral intake in the first 14 days and the trend of serum calcium (Ca), phosphorus (P), and alkaline phosphatase (ALP) levels were compared in both groups. RESULTS: The Ca and P supplementation in the first 2 weeks of life were inadequate in both groups. Compared with the control group, significantly lower serum P (mg/dL) levels were noted in the high-risk group on weeks 2 (3.65 ± 1.2 vs 4.67 ± 1.45; P < .001), 4 (3.21 ± 0.95 vs 5.83 ± 1.18; P < .0001), and 6 (3.94 ± 1.1 vs 6.22 ± 0.78; P <.0001). There was no significant difference in the serum Ca level, and significantly higher ALP (U/L) levels were found up until 2 months of life in the high-risk group (458.36 ± 189.02 vs 335.7 ± 111.51; P < .014). CONCLUSION: Hypophosphatemia developed as early as 2 weeks old in high-risk preterm infants because of inadequate supplementation. Neither the serum Ca or ALP levels were affected. Thus, the routine monitoring of serum P level should be started 2 weeks after birth for early MBD detection in extremely ELBW infants.

Risk factors for digestive morbidities after esophageal atresia repair.

Esophageal atresia with/without tracheoesophageal fistula (EA/TEF) is a congenital digestive tract anomaly that represents a major therapeutic challenge. Postoperative digestive morbidities such as gastroesophageal reflux disease (GERD) and esophageal stricture are common. The aim of this study was to identify the incidence of and potential risk factors for digestive morbidities after EA/TEF repair. We retrospectively reviewed all EA/TEF patients who underwent repair at a single institution between January 1999 and December 2018, excluding patients who died prior to discharge. Patient demographics, perioperative management, and postoperative GERD and esophageal stricture rates were collected. We performed univariate and multivariate analyses to examine risk factors associated with postoperative GERD and esophageal stricture. The study enrolled 58 infants (58.6% male, 17.2% with type A EA/TEF, 62.1% with associated anomalies). Postoperative GERD occurred in 67.2% of patients and was the most common digestive morbidity. Esophageal stricture occurred in 37.9% of patients after EA/TEF repair. Multivariate analysis showed that long-gap EA/TEF and postoperative GERD were independent risk factors for esophageal stricture after repair surgery.Conclusion: The incidence of postoperative GERD and esophageal stricture was 67.2% and 37.9%, respectively. The risk factors for postoperative esophageal stricture were long-gap EA/TEF and postoperative GERD. What is Known: • EA/TEF is a congenital digestive tract anomaly with a high postoperative survival rate but can be complicated by many long-term morbidities. What is New: • Long-gap EA/TEF and postoperative GERD are risk factors of anastomotic stricture after repair. • Surgeons and pediatricians should be highly experienced in managing anastomotic tension and the GERD.

TLD environmental monitoring of new scanner facilities at the Nuclear Medicine Department of the Taiwan Medical University Hospital.

OBJECTIVE: Single-photon emission computed tomography (SPECT) as well as dual energy X-ray absorptiometry (DXA) scanners were designed in July 2018 at the Nuclear Medicine Department (NM), of the Taiwan Medical University Hospital. These scanners emit substantial X-rays from the target, which are tungsten, iron. Therefore, patients undergoing SPECT and DXA diagnosis, in addition to medical personnel, are exposed to undesirable photon leakage. METHODS: Following administration of radiopharmaceuticals, patients become radioactive sources; thus, it is necessary to evaluate a possible increase in the environmental gamma exposure rates in the NM as a result of the operation of the new scanners. A three month evaluation of environmental radiation in the NM was performed using the accurate and sensitive TLD-100H approach, which gives an error rate less than 10%. RESULTS: Detected exposure radiation rates in the NM ranged from 0.12 ± 0.02 to 1.00 ± 0.15 mSv per month, indicating that the imaging room had significantly different radiation rates. The results were compared with previous results, and no significant contribution to the enhancement of environmental gamma radiation was detected, which remained far below the occupational dose recommended by ICRP 60. The minimum detectable dose (MDD) for environmental radiation is also discussed herein to demonstrate the reliability of TLD-100H. CONCLUSION: Recommendations were sent to the authorities of AEC-ROC to implement actions that could reduce doses at these high-dose locations to meet the ALARA principle.

Linear growth of corpus callosum and cerebellar vermis in very-low-birth-weight preterm infants.

BACKGROUND/PURPOSE: Impaired growth of the corpus callosum (CC) and cerebellar vermis (CV) is associated with poorer neurodevelopmental outcomes in preterm infants. However, references on the postnatal growth rate of the CC and CV by sonography are limited. The aim of this study is to assess the normal linear growth of CC and CV using a serial cranial ultrasound. METHODS: We prospectively enrolled preterm infants with very low birth weight from September 2008 to December 2009 after excluding those with congenital anomalies or diseases affecting the brain parenchyma. Serial sonographic measurements of the CC and CV were performed according to the standard protocol. Scheduled comprehensive neurodevelopmental evaluations were performed till the corrected age of 2 years. We excluded those with significant brain damages or poor neurodevelopmental outcomes in the final analysis. The growth rate was estimated using the loess smoothing curve and linear regression analysis. RESULTS: Among the 86 enrolled neonates, 14 with significant brain damage and 8 with poor neurodevelopmental outcomes were excluded from the final analysis. The growth rate of the CC length was 1.72 (95% confidence interval [CI]: 1.24-2.20) and 0.57 (95% CI: 0.33-0.80) mm per week before and after the postmenstrual age of 30.5 weeks, respectively. The growth rate of the CV length was 0.78 (95% CI: 0.68-0.89) mm per week. CONCLUSION: We proposed reference values of the normal linear growth rate of the CC and CV lengths in very-low-birth-weight preterm infants using the serial cranial ultrasound.

Use of sodium glycerophosphate in neonatal parenteral nutrition solutions to increase calcium and phosphate compatibility for preterm infants.

BACKGROUND: Preterm infants require higher calcium and phosphate intake than term infants to facilitate adequate bone growth, but this is rarely met in parenteral nutrition (PN) solution because of the limited solubility of calcium and phosphate. This study aimed to evaluate the solubility of organic phosphate with calcium gluconate in neonatal PN solutions, simulating its clinical use. METHODS: PN solutions were composed of calcium gluconate at 50 mEq/L and sodium glycerophosphate (NaGP) at 25 mmol/L. Another component included 1% or 4% amino acid and 10% or 20% dextrose. For comparison, PN solution composed of potassium phosphate was also evaluated. Each solution was evaluated using the following methods: visual inspection, light obscuration particle count test, and pH measurement. To simulate the clinical condition, the solution was tested after compounding, after being stored at 25 °C for 24 h, and after being stored at 2°C-8°C for 2 or 9 days and subsequently at 25 °C for 24 h. RESULTS: There was no visual deposition in PN solution using NaGP in any of the concentrations and under any stored condition. The solution fulfilled the criteria of physical compatibility as < 25 particles/mL measuring ≥10 µm in diameter and <3 particles/mL measuring ≥25 µm in diameter. On the contrary, visual deposition was evidently noted in PN solution using potassium phosphate after its formulation, and the particle count significantly exceeded the range of physical compatibility. CONCLUSION: NaGP and calcium gluconate have significantly good compatibility in PN solution. The use of NaGP in neonatal PN prevents calcium and phosphorus precipitation, hence increasing their supply to preterm infants in meeting their growth requirement.

Maternal exposure to air pollution and the risk of small for gestational age in offspring: A population-based study in Taiwan.

BACKGROUND: Exposure to air pollution has been associated with a wide range of adverse health effects; however, few studies addressed the relationship between ambient particulate matter as well as the compositions in particulate matter such as lead and the risk of small for gestational age (SGA) in offspring. The aim of this study is to investigate the effect of maternal exposure to criteria air pollutants and the lead in total suspended particulate matter during pregnancy on SGA births in Taiwan. METHODS: This population study consisted of 322,513 singleton live births in Taiwan between 1996 and 2002. Daytime (7 AM-7 PM) exposure to particulate matter ≤10 µm (PM10), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3), and monthly exposure to lead in total suspended particles (TSP) during each trimester were estimated. Generalized additive model (GAM) was used to assess the association between maternal exposure to particulate air pollutants and SGA births, taking into account potential confounders and gaseous air pollutants. RESULTS: We found significant association between the highest quartile (≥75th) of maternal PM10 exposure and SGA and demonstrated a significant exposure-response relationship. Furthermore, the highest quartile (≥75th) of maternal lead exposure was also associated with SGA during the second and third trimester of pregnancy, and there was a significant exposure-response relationship between maternal lead exposure and SGA during pregnancy. CONCLUSION: Maternal exposure to PM10 and lead in total suspended particulate matter during pregnancy was associated with an increased risk of SGA in offspring.