Biomedical subjects

Jing Liu

Publications and source records attributed to Jing Liu.

At least 289 records · Page 16Linked to original sources

PubMed2003

Disruption of type 5 adenylyl cyclase gene preserves cardiac function against pressure overload.

The sympathetic nervous system is designed to respond to stress. Adenylyl cyclase (AC) is the keystone of sympathetic transmission, yet its role in response to acute overload in the heart or in the pathogenesis of heart failure is controversial. We examined the effects of pressure overload, induced by thoracic aortic banding, in mice in which type 5 AC, a major cardiac AC isoform, was disrupted (AC5-/-). Left ventricular weight/tibial length ratio (LVW/TL) was not different between the WT and AC5-/- at baseline and increased progressively and similarly in both groups at 1 and 3 wk after aortic banding. However, LV ejection fraction (LVEF) fell in WT at 3 wk after banding (from 70 +/- 2.8 to 57 +/- 3.9%, P < 0.05), and this decrease was associated with LV dilatation, indicating incipient cardiac failure. In contrast, AC5-/- mice did not exhibit a fall in LVEF from 74 +/- 2.2%. The number of apoptotic myocytes was similar at baseline, but it increased roughly 4-fold in WT at both 1 and 3 wk after banding, and significantly less, P < 0.05, in AC5-/-. Importantly, the increase in apoptosis occurred before the decline in LVEF in WT. The protective mechanism seems to involve Bcl-2, which was up-regulated significantly more in AC5-/- mice with pressure overload. Our findings suggest that limiting type 5 AC plays a protective role in response to pressure overload and the development of heart failure, potentially through limiting the incidence of myocardial apoptosis.

Adenylyl Cyclases↗

PubMed2003

Type 5 adenylyl cyclase disruption alters not only sympathetic but also parasympathetic and calcium-mediated cardiac regulation.

In a genetically engineered mouse line with disruption of type 5 adenylyl cyclase (AC5-/-), a major cardiac isoform, there was no compensatory increase in other isoforms of AC in the heart. Both basal and isoproterenol (ISO)-stimulated AC activities were decreased by 30% to 40% in cardiac membranes. The reduced AC activity did not affect cardiac function (left ventricular ejection fraction [LVEF]) at baseline. However, increases in LVEF after ISO were significantly attenuated in AC5-/- (P<0.05, n=11). Paradoxically, conscious AC5-/- mice had a higher heart rate compared with wild-type (WT) mice (613+/-8 versus 523+/-11 bpm, P<0.01, n=14 to 15). Muscarinic agonists decreased AC activity, LVEF, and heart rate more in WT than in AC5-/-. In addition, baroreflex-mediated, ie, neuronally regulated, bradycardia after phenylephrine was also attenuated in AC5-/-. The carbachol-activated outward potassium current (at -40 mV) normalized to cell capacitance in AC5-/- (2.6+/-0.4 pA/pF, n=16) was similar to WT (2.9+/-0.3 pA/pF, n=27), but calcium (Ca2+)-mediated inhibition of AC activity and Ca2+ channel function were diminished in AC5-/-. Thus, AC5-/- attenuates sympathetic responsiveness and also impairs parasympathetic and Ca2+-mediated regulation of the heart, indicating that those actions are not only regulated at the level of the receptor and G-protein but also at the level of type 5 AC.

Acetylcholine↗

PubMed2003

Freezing curve-based monitoring to quickly evaluate the viability of biological materials subject to freezing or thermal injury.

This paper is aimed at investigating the roles of freezing dynamics of a liquid droplet to characterize the properties of the material. In particular, freezing curve-based monitoring was proposed to quickly evaluate the viability of biological materials subject to freezing, re-warming, or other kinds of injury, which is an extremely important issue in practices such as cryobiology, hyperthermia, or freshness evaluation of bio-samples. An integrated micro analysis device was fabricated which is simple in structure and cheap to make. Preliminary freezing results demonstrated that minor changes in a biological material due to freezing or warming injury might result in a significant deviation of its freezing curve from that of the intact biomaterials. Several potential thermal indexes to quantify the material features were pointed out. Further, experiments were performed on some freezing and thawing processes of small amount of water on a cooling surface to test the effects of droplet sizes, measurement sites, cooling strength, and cooling geometry, etc., on the freezing responses of a water droplet. Their implementation in developing a new micro analysis system were suggested. This freezing curve-based monitoring method may open a new strategy for the evaluation of biomaterials subject to destruction in diverse fields.

Animals↗

PubMed2003

[Expression and function of apoptosis-related genes Bcl-2/Bax and Fas/Fas L in the course of stress ulcer].

OBJECTIVE: To investigate the correlation between the expressions of apoptosis-promoting gene Bax, apotosis-inhibiting gene Bcl-2, and Fas/FasL in gastric mucosa in the course of stress ulcer. METHODS: Fifty-six rats were exposed to water immersion-restraint stress (WRS) and then randomly divided into 7 groups of 8 rats: WRS 2 h, RS 3.5 h, and 2 h, 5 h, 8 h, 12 h, and 24 h after termination of WRS. Another 8 rats were used as controls. The stomachs of rats were taken out at the above mentioned time points to observe histologically. Terminal deoxynucleatidyl transferase mediated dUTP nick and labeling (TUNEL) technique was used to examine the apoptotic cells in the gastric mucosa. The expression of Bcl-2/Bax protein was examined by immunohistochemical assay. In situ hybridization was used to detect the mRNA expression of Bcl-2, Fas, and FasL. RESULTS: (1) Apototic cells were seen sporadically in the gastric mucosa of the control rats. The number of apoptotic cells began to increase since 2 hours after the beginning of WPS and reached its peak 5 hours after the termination of WRS. Since 8 - 12 hours after the termination of WRS the number of apoptosis began to decrease, however, still remained at a level significantly higher than the normal level (P < 0.05). (2) Fas mRNA and FasL mRNA were not expressed in the controls. Fas mRNA was detected 5 - 8 hours after the termination of WRS at the base of mucosa at a low level and disappeared 8 hours after the termination of WRS. FasL mRNA was detected since WRS 3.5h to 8 hours after the termination of WRS. (3) In normal gastric mucosa, Bcl-1 mRNA and protein were expressed in gastric gland zone at a middle level and Bax protein was expressed in the epithelial cells. In WRS rats Bax protein expression began to be detected in the epithelial cells lining the gastric pits since WRS 2 h, then increased, reached the peak 2 - 5 hours after the termination of WRS, and then gradually decreased and remained a little higher than normal level 24 hours later (P < 0.05). Bcl-2 expression began to decrease since the termination of WRS and then increased 8 - 12 hours after the termination of WRS and reached the normal level 24 hours later (P > 0.05). Correlation analysis showed that the expression of Bax protein was correlated with the quantity of apotosis in gastric mucosa. CONCLUSION: The alterations of Bcl and Bax may be responsible for the development of mucosa lesion and recovery. The expression of Fas/FasL has no effect on the gastric mucosa apoptosis related to WRS. Overexpression of Bcl-2 may inhibit the Fas/FasL induced apoptosis.

Animals↗

PubMed2003

Monitoring of two-stage anaerobic biodegradation using a BOD biosensor.

A previously developed biosensor for fast estimation of short-term biochemical oxygen demand (BOD(st)) was used for off-line monitoring of intermediate products from the initial step of an anaerobic process in laboratory scale. Good agreement was generally achieved between the results from the biosensor method and the conventional 5-day test except for samples with high content of organic polymers. During the period of agreement between the measurement principles, good correlation was achieved between the biogas production rate and the organic loading rate. The results from this study demonstrate that BOD(st) can be a successful monitoring parameter to achieve a better process control.

Anaerobiosis↗

PubMed2003

Study of chromium-containing proteins in subcellular fractions of rat liver by enriched stable isotopic tracer technique and gel filtration chromatography.

Ten male Wistar rats were intravenously injected with a single approximately physiological dose of enriched stable isotopic Cr-50 tracer solution (200 ng (50)Cr(3+)/100 g body wt). The fundamental distribution patterns of the chromium-containing proteins in the nucleic, mitochondrial, lysosomal, microsomal, and cytosolic subcellular fractions of the rat liver were investigated by means of Sephadex G-100 gel chromatography combined with neutron activation analysis via (50)Cr (n, gamma) (51)Cr reaction. In total, nine kinds of Cr-containing proteins were found in the five subcellular fractions, whose relative molecular masses were 96.6+/-6.2, 68.2+/-1.4, 57.9+/-4.7, 36.6+/-1.2, 24.2+/-1.8, 14.0+/-1.5, 8.8+/-0.6, 6.9+/-0.4, and 4.2+/-0.4 kDa. Approximately 64.5% of Cr proteins accumulated in the cytosolic fraction. The second enriched part was the nucleic fraction; about 12.2% Cr proteins were stored in this section. The 4.2-kDa molecular mass might contain the so-called low molecular weight chromium-containing substance; however, in this research, it was only observed in the mitochondria, lysosome, and microsome. In the mitochondrial fraction, most of the Cr proteins were present as relatively low molecular weight substances: about 56% of chromium-containing proteins had molecular masses < or =6.9 kDa. Nevertheless, more than 69% of Cr-containing proteins were observed with molecular masses > or =57.9 kDa in the liver cytosolic fraction.

Animals↗

PubMed2003

Spinal cord injury increases iron levels: catalytic production of hydroxyl radicals.

This study used a weight drop impact injury model to explore the role of iron and the reality of iron-catalyzed hydroxyl radical ((*)OH) formation in secondary spinal cord injury (SCI). The time course of total extracellular iron was measured following SCI by microcannula sampling and atomic absorption spectrophotometry analysis. Immediately following SCI, the total iron concentration increased from an undetectable level to an average of 1.32 microM. The time course of SCI-induced (*)OH-generating catalytic activity in the cord was obtained by determining the ability of tissue homogenate to convert hydrogen peroxide to (*)OH and then measuring 2,3-dihydroxybenzoic acid, a hydroxylation product of salicylate. The concentration of 2,3-DHBA quickly and significantly increased (p <.001) and returned to sham level (p = 1) by 30 min post-SCI. Desferrioxamine (80 and 800 mg/kg body weight) significantly (p <.001) reduced the catalytic activity, suggesting that iron is the major contributor of the activity. Administering FeCl(3) (100 microM)/EDTA (0.5 mM) in ACSF into the cord through a dialysis fiber significantly increased SCI-induced (*)OH production in the extracellular space, demonstrating that Fe(3+) can catalyze (*)OH production in vivo. Our results support that iron-catalyzed (*)OH formation plays a role in the early stage of secondary SCI.

Animals↗

PubMed2003

Broadly cross-reactive mimotope of hypervariable region 1 of hepatitis C virus derived from DNA shuffling and screened by phage display library.

The hypervariable region 1 (HVR1) is the target of neutralizing antibodies but with isolate specificity. The aim of this study was to obtain immunogenic mimotopes of HVR1, which can react broadly with different HVR1 antibodies and could be one of the candidate immunogens in an effective vaccine against HCV. Thirty-one HVR1 cDNA fragments were digested by DNase I into a pool of random fragments and reassembled by repeated cycles of annealing in the presence of DNA polymerase to their original size. The shuffled HVR1 was then inserted into the gene III phagemid vector pCANTAB-5E and displayed on the surface of the phage. Eight individual phages were selected after four rounds of biopanning against anti-HVR1. ELISA was carried out on immobilized purified phages, respectively, to detect their reactivity with a panel of sera. DNA sequences of the inserts were analyzed and compared with the consensus sequences defined by Puntoriero et al. [(1998) EMBO J 17:3521-3533]. The reactivity of the eight selected clones to the 30 sera were from 53.3 to 80%. Among these, phage 13 (ETYVSGGSAARNAYGLTSLFTVGPAQK, aa 384-410) reacted most broadly. None of the selected sequences encoded for peptides corresponded to known HVR1 from original viral isolates. The two high reactive phages had the similar amino acid sequences with the consensus, which might play a particular role in determining the frequency of reactivity. In conclusion, this study has used effectively DNA shuffling combined with phage display technology to identify broadly cross-reactive mimotopes recognized by human polyclonal antibodies. Mimotope 13 and 23 appeared to be most reactive immunologically and could be candidate immunogens. Efforts are now underway to identify their neutralizing antibodies by immunization of animals.

Amino Acid Sequence↗

PubMed2003

Humanized anti-CD25 monoclonal antibody for prophylaxis of graft-vs-host disease (GVHD) in haploidentical bone marrow transplantation without ex vivo T-cell depletion.

OBJECTIVE: To investigate the effects of a novel anti-IL-2 receptor (CD25) monoclonal antibody, basiliximab, on graft-vs-host disease (GVHD) and engraftment in haploidentical bone marrow transplantation (BMT). MATERIALS AND METHODS: Thirteen consecutive high-risk leukemia patients (age 9-41) underwent haploidentical BMT with G-CSF-primed marrow as stem cells without ex vivo T-cell depletion. Basiliximab, along with a combination of cyclosporine (CSA), methotrexate (MTX), and mycophenolate mofetil (MMF), was used for GVHD prophylaxis. Immunophenotyping, limited-dilution assay, and colony-forming assays were used to measure the effect of basiliximab on the subsets of lymphocytes, cytotoxic T-lymphocyte precursors (CTLp), and hematopoietic cells. RESULTS: All patients established successful trilineage engraftment with full donor chimerism. No patients developed grade II-IV acute GVHD. Patients who survived more than 12 months and were free of relapse showed limited chronic skin GVHD. Ten of 13 patients are currently alive with a Karnofsky performance score of 100% at median follow-up of 17 months (range 12-24 months). Basiliximab significantly decreased alloreactive CTLp by 10-fold to 100-fold in limiting-dilution assays. It had no effect on hematopoietic stem and progenitor cells as determined by in vitro colony-forming assays. CONCLUSION: The addition of basiliximab to CSA, MMF, and MTX as GVHD prophylaxis effectively reduced severe lethal GVHD in haploidentical BMT. It is possible to selectively eliminate or reduce the number of alloreactive T cells with anti-CD25 antibody, which results in prevention of or a reduction in the severity of GVHD.

Adolescent↗

PubMed2003

Multiple fibroelastomas: a case report and review of the literature.

Cardiac papillary fibroelastoma is a rare primary cardiac tumor that usually involves the heart valves. Multiple fibroelastomas found in a single patient is an even more rare occurrence. We describe the case of a 41-year-old woman who presented with an acute cerebrovascular accident, and was found to have 4 separate fibroelastoma tumors involving the aortic and mitral valves. The role of echocardiography in the diagnosis of this unusual tumor and its therapy is discussed.

Adult↗

PubMed2003

Gene identification and expression analysis of 86,136 Expressed Sequence Tags (EST) from the rice genome.

Expressed Sequence Tag (EST) analysis has pioneered genome-wide gene discovery and expression profiling. In order to establish a gene expression index in the rice cultivar indica, we sequenced and analyzed 86,136 ESTs from nine rice cDNA libraries from the super hybrid cultivar LYP9 and its parental cultivars. We assembled these ESTs into 13,232 contigs and leave 8,976 singletons. Overall, 7,497 sequences were found similar to existing sequences in GenBank and 14,711 are novel. These sequences are classified by molecular function, biological process and pathways according to the Gene Ontology. We compared our sequenced ESTs with the publicly available 95,000 ESTs from japonica, and found little sequence variation, despite the large difference between genome sequences. We then assembled the combined 173,000 rice ESTs for further analysis. Using the pooled ESTs, we compared gene expression in metabolism pathway between rice and Arabidopsis according to KEGG. We further profiled gene expression patterns in different tissues, developmental stages, and in a conditional sterile mutant, after checking the libraries are comparable by means of sequence coverage. We also identified some possible library specific genes and a number of enzymes and transcription factors that contribute to rice development.

Arabidopsis↗

PubMed2003

Construction, expression and characterization of the engineered antibody against tumor surface antigen, p185(c-erbB-2).

The c-erbB-2 proto-oncogene encodes a 185kDa protein p185, which belongs to epidermal growth factor receptor family. Amplification of this gene has been shown to correlate with poor clinical prognosis for certain cancer patients. The monoclonal antibody A21 which directed against p185 specifically inhibits proliferation of tumor cells overexpressing p185, hence allows it to be a candidate for targeted therapy. In order to overcome several drawbacks of murine MAb, we cloned its VH and VL genes and constructed the single-chain Fv (scFv) through a peptide linker. The recombinant scFvA21 was expressed in Escherichia coli and purified by the affinity column. Subsequently it was characterized by ELISA, Western blot, cell immunohistochemistry and FACS. All these assays showed the binding activity to extracellular domain (ECD) of p185. Based on those properties of scFvA21, we further constructed the scFv-Fc fusion molecule with a homodimer form and the recombinant product was expressed in mammalian cells. In a series of subsequent analysis this fusion protein showed identical antigen binding site and activity with the parent antibody. These anti-p185 engineered antibodies have promised to be further modified as a tumor targeting drugs, with a view of application in the diagnosis and treatment of human breast cancer.

Amino Acid Sequence↗

PubMed2003

The Maternal Lifestyle Study (MLS): effects of prenatal cocaine and/or opiate exposure on auditory brain response at one month.

OBJECTIVE: To study absolute and interpeak latencies of the auditory brain response in infants exposed to cocaine and/or opiates in utero.Study design The sample included 477 exposed and 554 comparison infants matched for race, sex, and gestational age. Mothers were recruited at 4 urban university-based centers; most were black, receiving public assistance, and had received adequate prenatal care. Exposure was determined by meconium assay and self-report with alcohol, marijuana, and tobacco present in both groups. At 1 month, infants were tested by masked examiners with the auditory brain response. RESULTS: Analyses were conducted for exposed and comparison groups and for level of prenatal cocaine exposure with adjustment for covariates (alcohol, marijuana, tobacco, gestational age at birth, social class, and site). Heavy prenatal cocaine exposure (>/=3 days per week, first trimester) led to an increase in the I-III, I-V, and III-V interpeak latencies and to a shorter latency to peak I. Infants with prenatal opiate exposure showed a longer latency to peak V and a longer III-V interpeak latency. CONCLUSIONS: Prenatal cocaine and/or opiate exposure affects neural transmission. Detection of these effects requires a large sample with control for gestational age, other drugs, and level of cocaine use.

Alcohol Drinking↗

PubMed2003

Three monophyletic superfamilies account for the majority of the known glycosyltransferases.

Sixty-five families of glycosyltransferases (EC 2.4.x.y) have been recognized on the basis of high-sequence similarity to a founding member with experimentally demonstrated enzymatic activity. Although distant sequence relationships between some of these families have been reported, the natural history of glycosyltransferases is poorly understood. We used iterative searches of sequence databases, motif extraction, structural comparison, and analysis of completely sequenced genomes to track the origins of modern-type glycosyltransferases. We show that >75% of recognized glycosyltransferase families belong to one of only three monophyletic superfamilies of proteins, namely, (1) a recently described GPGTF/GT-B superfamily; (2) a nucleoside-diphosphosugar transferase (GT-A) superfamily, which is characterized by a DxD sequence signature and also includes nucleotidyltransferases; and (3) a GT-C superfamily of integral membrane glycosyltransferases with a modified DxD signature in the first extracellular loop. Several developmental regulators in Metazoans, including Fringe and Egghead homologs, belong to the second superfamily. Interestingly, Tout-velu/Exostosin family of developmental proteins found in all multicellular eukaryotes, contains separate domains belonging to the first and the second superfamilies, explaining multiple glycosyltransferase activities in one protein.

Amino Acid Sequence↗

PubMed2003

Functional organization of speed tuned neurons in visual area MT.

We analyzed the functional organization of speed tuned neurons in extrastriate visual area MT. We sought to determine whether neurons tuned for particular speeds are clustered spatially and whether such spatial clusters are elongated normal to the cortical surface so as to form speed columns. Our data showed that MT neurons are indeed clustered according to preferred speed. Multiunit recordings were speed tuned, and the speed tuning of these signals was well correlated with the speed tuning of single neurons recorded simultaneously. To determine whether speed columns exist in MT, we compared the rates at which preferred speed changed in electrode tracks that traversed MT obliquely and normally to the cortical surface. If speed columns exist, the preferred speed should change at a faster rate during oblique electrode tracks. We found, however, that preferred speed changed at similar rates for either type of penetration. In the same data set, the rate of change of preferred direction and preferred disparity differed substantially in normal and oblique penetrations as expected from the known columnar organization of MT. Thus our results suggest that a columnar organization for speed tuned neurons does not exist in MT.

Animals↗

PubMed2003

Activation of Mst1 causes dilated cardiomyopathy by stimulating apoptosis without compensatory ventricular myocyte hypertrophy.

Activation of mammalian sterile 20-like kinase 1 (Mst1) by genotoxic compounds is known to stimulate apoptosis in some cell types. The importance of Mst1 in cell death caused by clinically relevant pathologic stimuli is unknown, however. In this study, we show that Mst1 is a prominent myelin basic protein kinase activated by proapoptotic stimuli in cardiac myocytes and that Mst1 causes cardiac myocyte apoptosis in vitro in a kinase activity-dependent manner. In vivo, cardiac-specific overexpression of Mst1 in transgenic mice results in activation of caspases, increased apoptosis, and dilated cardiomyopathy. Surprisingly, however, Mst1 prevents compensatory cardiac myocyte elongation or hypertrophy despite increased wall stress, thereby obscuring the use of the Frank-Starling mechanism, a fundamental mechanism by which the heart maintains cardiac output in response to increased mechanical load at the single myocyte level. Furthermore, Mst1 is activated by ischemia/reperfusion in the mouse heart in vivo. Suppression of endogenous Mst1 by cardiac-specific overexpression of dominant-negative Mst1 in transgenic mice prevents myocyte death by pathologic insults. These results show that Mst1 works as both an essential initiator of apoptosis and an inhibitor of hypertrophy in cardiac myocytes, resulting in a previously unrecognized form of cardiomyopathy.

Alkaloids↗

PubMed2003

Inhibition of endogenous thioredoxin in the heart increases oxidative stress and cardiac hypertrophy.

Thioredoxin 1 (Trx1) has redox-sensitive cysteine residues and acts as an antioxidant in cells. However, the extent of Trx1 contribution to overall antioxidant mechanisms is unknown in any organs. We generated transgenic mice with cardiac-specific overexpression of a dominant negative (DN) mutant (C32S/C35S) of Trx1 (Tg-DN-Trx1 mice), in which the activity of endogenous Trx was diminished. Markers of oxidative stress were significantly increased in hearts from Tg-DN-Trx1 mice compared with those from nontransgenic (NTg) mice. Tg-DN-Trx1 mice exhibited cardiac hypertrophy with maintained cardiac function at baseline. Intraperitoneal injection of N-2-mercaptopropionyl glycine, an antioxidant, normalized cardiac hypertrophy in Tg-DN-Trx1 mice. Thoracic aortic banding caused greater increases in myocardial oxidative stress and enhanced hypertrophy in Tg-DN-Trx1 compared with NTg mice. In contrast, transgenic mice with cardiac-specific overexpression of wild-type Trx1 did not show cardiac hypertrophy at baseline but exhibited reduced levels of hypertrophy and oxidative stress in response to pressure overload. These results demonstrate that endogenous Trx1 is an essential component of the cellular antioxidant mechanisms and plays a critical role in regulating oxidative stress in the heart in vivo. Furthermore, inhibition of endogenous Trx1 in the heart primarily stimulates hypertrophy, both under basal conditions and in response to pressure overload through redox-sensitive mechanisms.

Animals↗

PubMed2003

Smoking during pregnancy and newborn neurobehavior.

OBJECTIVE: This was a prospective study of the effects of maternal smoking during pregnancy on newborn neurobehavior, including dose-response relationships using self-report and a bioassay of nicotine exposure. METHODS: The sample included 27 nicotine exposed and 29 unexposed full-term newborn infants with no medical problems from comparable social class backgrounds. Mothers were excluded for using illegal drugs during pregnancy, using antidepressant medication, or if they consumed >3 alcoholic drinks per month. Nicotine exposure was determined by maternal self-report and cotinine in maternal saliva. The NICU Network Neurobehavioral Scale (NNNS) was administered by masked examiners in hospital to measure neurobehavioral function. NNNS scores were compared between nicotine-exposed and -unexposed groups including adjustment for covariates. Dose-response relationships with NNNS scores were computed for maternal salivary cotinine and maternal report of number of cigarettes per day during pregnancy. RESULTS: After adjustment for covariates, the tobacco-exposed infants were more excitable and hypertonic, required more handling and showed more stress/abstinence signs, specifically in the central nervous system (CNS), gastrointestinal, and visual areas. Dose-response relationships showed higher maternal salivary cotinine values related to more stress/abstinence signs (r =.530) including CNS (r =.532) and visual stress (r =.688) and higher excitability scores (r =.617). Cigarettes per day during pregnancy was related to more stress/abstinence signs (r =.582) including CNS (r =.561) and visual stress (r =.640). CONCLUSIONS: These findings suggest neurotoxic effects of prenatal tobacco exposure on newborn neurobehavior. Dose-response relationships could indicate neonatal withdrawal from nicotine. Research directed at understanding the effects of cigarette smoking during pregnancy on infants can lead to improved public health outcome.

Adolescent↗