[Application of two kinds of electrophysiological monitoring techniques for the prediction of facial nerve outcomes after vestibular Schwannoma surgery].

Objective: To investigate the application of transcranial facial nerve motor evoked potential (FNMEP) and direct nerve electrical stimulation (DNES) for the prediction of facial nerve function after vestibular schwannoma surgery. Methods: The clinical data of 106 patients who underwent vestibular schwannoma surgery under electrophysiological monitoring of facial nerve between 2017 and 2021 were retrospectively examined, and there were 57 males and 49 females, with a mean age of (51±11) years. Neuroelectrophysiological monitoring was performed in all patients during the operation. After the tumor was removed, FNMEP and DNES were used for electrophysiological evaluation of facial nerve function. The amplitude ratios of FNMEP to baseline (M1) and the brainstem segment to the internal auditory canal segment of DNES (M2) were recorded after the tumor was removed, respectively. The correlation between these two ratios and facial nerve function at 1 day, 1 month and 3 months after the operation were compared. According to the House-Brackmann (HB) scale, Grade Ⅰ-Ⅱ refers to good facial nerve function, and grade Ⅲ-Ⅵ refers to moderate and severe facial nerve dysfunction. Non-parameter Spearman correlation coefficient was used to evaluate the correlation between M1 and M2 and facial nerve function at 1 day, 1 month and 3 months after operation, and the receiver operating characteristic (ROC) curves were plotted to verify the diagnostic efficacy of M1 and M2 for predicting the prognosis of postoperative facial nerve function. Results: Among 106 patients, 102 cases (96.3%) underwent total tumor resection, 4 patients (3.7%) underwent subtotal resection, 104 patients (98.1%) had anatomical preservation of facial nerves, and there were no deaths reported. All patients could evoke reliable FNMEP and 2 patients could not evoke DNES in the brainstem segment of the facial nerve. There were 81 (76.4%), 99 (93.4%) and 103 patients (97.2%) with satisfactory function of facial nerve at 1 day, 1 month and 3 months after surgery, respectively. M1 had large absolute values of Spearman correlation coefficient at 1 day (ρ=|-0.648|) and 1 month (ρ=|-0.552|) after surgery (both P<0.001), while M2 showed a greater absolute value of Spearman correlation coefficient at 3 months (ρ=|-0.395|) than that of M1 (ρ=|-0.378|) (P<0.001). Cut-off value of M1 was 0.58 (sensitivity=0.92, specificity=0.64), and that of M2 was 0.36 (sensitivity=0.64, specificity=1.00). Meanwhile, M1<0.58 or M2<0.36 suggested moderate and severe impairment of facial nerve function. Conclusions: Both FNMEP and DNES during vestibular schwannoma surgery can effectively evaluate the postoperative facial nerve function. FNMEP is better than DNES in predicting the early postoperative facial nerve function, but DNES is better for predicting the long-term postoperative facial nerve function.

[The clinical values of neutrophil-to-lymphocyte ratio as an early predictor of anastomotic leak in postoperative rectal cancer patients].

Objective: To assess the clinical value of neutrophil-to-lymphocyte ratio (NLR) in predicting anastomotic leak of postoperative rectal cancer patients. Methods: The clinical data of 787 rectal cancer patients who underwent anterior resection from January 2014 to December 2017 in Affiliated Tumor Hospital of Zhengzhou University were collected. The postoperative numbers of white blood cell (WBS) on postoperative day (POD)1, 3 and 5 were detected, and the NLR was calculated. The relationship of NLR and the incidence of anastomotic leak was analyzed, and the area under the receiver-operating characteristic (ROC) curves was calculated. The accuracy of postoperative NLR in predicting the incidence of anastomotic leak was evaluated. Results: WBC counts of patients with leak on POD1, POD3 and POD5 were 13.2×10(9)/L, 9.1×10(9)/L and 8.9×10(9)/L, respectively, while those of patients without leak were 12.9×10(9)/L, 9.0×10(9)/L and 8.8×10(9)/L. The WBC count was not significantly different between patients with or without leak (P>0.05). The average NLR values of patients with or without leak were 13.3 and 11.6 on POD1, 10.9 and 7.6 on POD3, 9.3 and 5.3 on POD5, respectively. The NLR values of patients with leak on POD3 and POD5 were significantly higher than those of patients without leak (P<0.05). The cutoff value of NLR on POD3 was 8.6, the sensitivity and specificity of detecting the leakage was 73.2% and 75.6%, respectively, and the area under curve (AUC) was 0.744. The cutoff value of NLR on POD5 was 5.5, the sensitivity and specificity was 69.6% and 75.5%, the AUC was 0.726. The multivariate analysis result showed that NLR >8.6 was an independent factor for anastomotic leak prediction. Conclusion: Postoperative NLR on day 3 is useful in predicting anastomotic leak and can decrease the incidence of complication in rectal cancer patients who underwent anterior resection.

[Types and treatment of easily-missed, misdiagnosed intestinal obstruction after radical radiotherapy of cervical cancer].

Objective: To investigate the types and treatment methods of easily-missed, misdiagnosed intestinal obstruction after radical radiotherapy of cervical cancer. Methods: The clinical data of 21 patients with intestinal obstruction after radical radiotherapy of cervical cancer in our hospital from May 2013 to May 2019 were collected, including the radiation dose, obstruction symptoms, surgical methods and treatment outcomes. The types and treatment methods of intestinal obstruction after radical radiotherapy of cervical cancer were further investigated. Results: The intestinal obstruction occurred in 21 patients with cervical cancer after radical radiotherapy. All patients were initially diagnosed as rectal obstruction and underwent the transverse colostomy. The obstruction symptoms were successfully resolved in 15 patients while failed in other 6 patients who then underwent the re-operation. Four patients with rectal obstruction accompanied by middle or terminal ileum obstruction underwent ileostomy, the other 2 patients with terminal ileum obstruction underwent the transverse ileal anastomosis and partial intestines exclusion surgery. All of the obstruction symptoms were alleviated. Conclusions: Rectal is the major obstruction site of the cervical cancer patients with intestinal obstruction after radical radiotherapy. However, a possibility of obstruction at the middle or end of the ileum also exists. Therefore, it is very important to avoid misdiagnosis and conduct appropriate operative treatment according to the obstruction site.

[Retrospective analysis of curative effect of total pelvic organ resection and anal preservation in 20 patients with recurrence of cervical cancer after radical radiotherapy].

Objective: To explore the surgical method and effect of en bloc pelvic resection and anal preservation after radical radiotherapy for cervical cancer. Methods: Clinical data of 20 cervical cancer patients with central recurrence after radical radiotherapy underwent en bloc pelvic resection in the Tumor Hospital of Zhengzhou University and Hainan Provincial People's Hospital from January 2013 to December 2017 were retrospectively analyzed. The operative time, intraoperative blood loss, length of stay, postoperative anal function and postoperative complications were evaluated. Results: The median operation time of 20 patients with anal preservation after en bloc pelvic resection was 135.2 min, the median intraoperative blood loss was 680 ml, and the median hospitalization time was 16.5 days. Among them, 18 patients had good postoperative healing, and the anal function gradually returned to normal within 6 months after surgery, defecated 1~2 times per day.One patient showed incomplete adhesion between the external colon and the anus. One patient presented with pre-sacral infection. Postoperative pathology confirmed the recurrences in 20 patients, of which 11 cases were squamous cell carcinoma, 7 cases were adenocarcinoma, 2 cases were adenosquamous cell carcinoma. Conclusions: It is safe and reliable to preserve anus after en bloc pelvic resection for cervical cancer patients with radical radiotherapy. The anus function is good enough to improve the postoperative life quality of patients significantly.

[Application of carbon nanoparticles labeled node staining in D2 radical resection of gastric cancer with neoadjuvant chemotherapy].

Objective: To explore the application value of carbon nanoparticles labeled node staining in D2 radical resection of gastric cancer with neoadjuvant chemotherapy. Methods: The retrospective cohort study was conducted. The clinicopathological data of 82 patients with gastric cancer who were admitted to Henan Tumor Hospital from April 2016 to April 2019 were collected. 38 patients who used carbon nanoparticles labeled node staining were in the observation group, while other 44 patients were in the control group. Data analysis including the operation and results of harvested of lymph nodes. Results: All patients successfully completed the operation.Thirty-eight patients successfully completed the injection of carbon nanoparticles. Surgery: observation group operating time was (150±28) min, intraoperative blood loss was (207±121) ml, group operating time was (140±23) min, intraoperative blood loss was (256±182) ml. There was no statistically significant difference between the two groups. Detection of Lymph node: A total of 1 260 lymph nodes were detected in the observation group and 981 in the control group. In the observation group, the mean lymph node sorting time was (17.2±3.3) min, the average number of harvested lymph node was 33.2±10.4, the number of the first station of lymph node was 19.8±5.3, the second station of lymph node was 13.4±6.4, the number of harvested small node(<5 mm) was 673, the positive lymph nodes was 13(range,1-31). They were all higher than those in the control group, which were (20.6±4.4)min,22.3±6.6, 12.6±4.1, 9.7±3.2,432,6 (range,1-13) , respectively. The difference between the two groups was statistically significant (P<0.05). The metastasis rate was 19.1% (241/1 260) in observation group and 16.5%(162/981) in the control group. The difference was no statistical(P>0.05). The rate of black -dyed harvested lymph node was 54.4%(686/1 260) in carbon nanoparticles group. Conclusions: The application of carbon nanoparticles labeled node staining in D2 radical resection of gastric cancer with neoadjuvant chemotherapy is feasible and safe. It can increase the number of lymph nodes detected, which is beneficial to the evaluation of chemotherapy effect and prognosis of patients.

Association between malaria incidence and meteorological factors: a multi-location study in China, 2005-2012.

This study aims to investigate the climate-malaria associations in nine cities selected from malaria high-risk areas in China. Daily reports of malaria cases in Anhui, Henan, and Yunnan Provinces for 2005-2012 were obtained from the Chinese Center for Disease Control and Prevention. Generalized estimating equation models were used to quantify the city-specific climate-malaria associations. Multivariate random-effects meta-regression analyses were used to pool the city-specific effects. An inverted-U-shaped curve relationship was observed between temperatures, average relative humidity, and malaria. A 1 °C increase of maximum temperature (T max) resulted in 6·7% (95% CI 4·6-8·8%) to 15·8% (95% CI 14·1-17·4%) increase of malaria, with corresponding lags ranging from 7 to 45 days. For minimum temperature (T min), the effect estimates peaked at lag 0 to 40 days, ranging from 5·3% (95% CI 4·4-6·2%) to 17·9% (95% CI 15·6-20·1%). Malaria is more sensitive to T min in cool climates and T max in warm climates. The duration of lag effect in a cool climate zone is longer than that in a warm climate zone. Lagged effects did not vanish after an epidemic season but waned gradually in the following 2-3 warm seasons. A warming climate may potentially increase the risk of malaria resurgence in China.

[Surgical resection for gastric cancer patients with liver metastasis].

Objective: To explore the surgical results and clinicopathological features of gastric cancer patients with liver metastases. Methods: The clinicopathological data and post-operative survival of 37 patients who underwent resection of liver metastasis from gastric cancer at our department from Dec. 2007 to Dec. 2014 were analyzed. Results: The 1-, 3-, and 5-year overall survival rates after resection were 91.4%, 57.9%, and 22.0%, respectively, with a median survival of 37 months. Univariate analysis revealed that lymph node metastasis, multiple hepatic metastases and no preoperative chemotherapy are unfavorable prognostic factors for overall survival. Multivariate analysis identified that lymph node metastasis and number of liver metastasis are independent prognostic factors. Conclusions: Gastric cancer patients with a solitary liver metastasis may be good candidates for gastric D2 resection combined with liver R0 resection.

[CT typing and surgical approach for adenocarcinoma of the esophagogastric junction].

Objective: To investigate the feasibility, safety and efficacy of preoperative CT in the classification of adenocarcinoma of the esophagogastric junction. Methods: A total of 517 consecutive patients from May 2012 to June 2016 with esophagogastric junction carcinoma in the department of general surgery of Henan Cancer Hospital was retrospectively analyzed, according to the clinical pathological data of three type four layer method and statistics of various types of surgery in patients with preoperative enhanced CT. Results: 517 patients were successfully received surgery, including 152 cases of type Ⅰ(131 cases of complete abdominal surgery, 21 cases of abdominal incision diaphragm in thoracic surgery), 239 cases of type Ⅱ (177 cases of complete abdominal surgery, 62 cases of abdominal incision diaphragm in thoracic surgery), Ⅲ/Ⅳ type choice of chest abdominal surgery in 126 cases. The operation time was (102±17) min, the amount of hemorrhage was (136±18) ml, the dominant anastomotic fistula happened in 16 cases, 5 cases of pancreatic fistula, 7 cases of intestinal obstruction, anastomotic stenosis in 3 cases, thoracic and abdominal sensation in 12 cases, all the complications were cured by conservative treatment. The average value of esophageal resection margin was(5.1±0.6)cm, 2 cases with positive residual tumor margin and average length of stay was (8.9±1.6)d. Conclusion: Using preoperative enhanced CT in the adenocarcinoma of the esophagogastric junction to choose surgical approach can ensure the safety margin. What's more, unnecessary thoracotomy is reduced which is expected to be a new classification method for the operation of esophagogastric junction cancer.

[The advantage of artery approach in lymph node sorting of rectal cancer].

Objective: To explore the technical advantages of artery approach in lymph node sortingofrectal cancer. Methods: Sixty patients with rectal cancer who treated in general surgery department of Henan provincial tumor hospitalfrom July 2015 to January 2016 were enrolled. Patientswere divided into two groupsrandomly.Lymph node sorting methods of control group andobservation group were the traditional method and the artery approach method respectively. The total number of lymph nodes, the average inspection number, the patients number of lymph nodes less than 12, the number of positive lymph nodes, the metastasis rate of the patients, the number of average diameter less than 5 mm, the number of the positive lymph nodes which average diameter less than 5 mm, the sorting time of lymph nodes, the total number of every stationand other indicators were collected and compared. Results: There wasa significant difference between the observation group and the control groupin the total number(553 vs 395, P<0.05), the number of positive ones(96 vs 54, P<0.05), average inspection number(18.43±5.93 vs 13.27±1.96, P=0.000), the sorting time (min) (14.1±2.5 vs 17.4±3.2, P=0.000), the average diameter less than 5 mm number(4.73±1.31 vs 1.23±1.14, P=0.000), the number of positive ones average diameter less than 5 mm(0.97±1.03 vs 0.20±0.55, P=0.010), the first(8.17±4.58 vs 5.07±1.96, P=0.000) and second station(6.57±1.87 vs 4.90±1.69, P=0.001)inspection number.The inspection number less than 12, the positive rate of lymph node, the metastatic rate of the patient and the inspection number of third station have no significant differences (all P≥0.05). Conclusion: Theartery approach method inrectal cancer lymph node inspectionhas many advantages such as simple operation, obtaining more lymph nodes and more accurate pathological staging.

[Treatment of advanced Siewert type â ¡ esophagogastric junction adenocarcinoma by thoracoabdominal radical gastrectomy and D2 lymphadenectomy].

OBJECTIVE: To investigate the advantages of thoracoabdominal radical gastrectomy for advanced Siewert type Ⅱ adenocarcinoma of the esophagogastric junction. METHODS: Clinical data of 86 patients with Siewert type Ⅱ adennocarcinoma of the esophagogastric junction who received surgical treatment at the Henan Provincial Tumor Hospital from January 2015 to January 2016 were retrospectively analyzed. Among them, 44 patients underwent abdominal operation (abdominal group), and 42 patients underwent thoracoabdominal radical gastrectomy (thoraco-abdominal group). The operation time, lymph node number, distance between the tumor and cutting edge, amount of intraoperational blood loss, postoperative pulmonary complications, and postoperative hospital stay in the two groups were compared. RESULTS: Comparing the thoracoabdominal group with the abdominal group, the number of removed lymph nodes was 41.57±9.22 vs. 35.09±10.61 (P<0.01), the number of removed mediastinal lymph nodes was 6.38±1.50 vs. 3.52±1.42 (P<0.01), the distance between the tumor and cut edge was (5.62±0.73) cm vs. (3.30±0.85) cm (P<0.01), whereas the operation time, intraoperative blood loss, postoperative pulmonary complications, occurrence of anastomotic leakage and hospital stay were statistically not significantly different (P>0.05 for all). CONCLUSIONS: For patients with advanced Siewert type Ⅱ adenocarcinoma of the esophagogastric junction, radical gastrectomy through thoracoabdominal approach can resect a longer segment of the esophagus, dissect more mediastinal lymph nodes, and does not increase post-operative complications and extend hospital stay, thus, exhibits obvious advantages in the surgical treatment of Siewert Ⅱ adenocarcinoma of the esophagogastric junction.

Determination of molecular weights of caprine milk proteins by matrix-assisted laser desorption/ionization mass spectrometry.

Molecular weights (MW) of major proteins in milk of 3 Korean dairy goat breeds were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, after treatment of milk samples with the reduction buffer used in capillary electrophoresis. The MW of caprine milk proteins were compared with those of Holstein milk counterparts using commercial bovine milk protein standards. The MW of α-lactalbumin, ß-lactoglobulin, and α- and ß-casein standards were 14,197±3.4, 18,326±26.3, 23,591±13.0, and 23,967±12.8 m/z, respectively, whereas those of Holstein milk treated with the reduction buffer were 14,199±8.3, 18,397±25.9, 23,614±64.8, and 23,984±75.6 m/z, respectively. The respective MW of α-lactalbumin in Saanen, Toggenberg, and Alpine milk were 14,194±27.2, 14,266±105.9, and 14,241±13.2 m/z, which were not different from those of the bovine milk. The respective MW of ß- lactoglobulin in corresponding caprine milk were 18,840±31.5, 18,856±26.3, and 18,857±21.3 m/z, which were higher than those in the bovine milk. The MW of ß-casein in corresponding caprine milk were 23,860±27.2, 23,886±12.3, and 23,901±8.4 m/z, which were lower than those in the bovine milk. The results indicated that matrix-assisted laser desorption/ionization time-of-flight mass spectrometry could be used for rapid determination of MW of Korean caprine milk proteins without protein separation steps.

[Safety of two and a half layered esophagojejunal anastomosis in total gastrectomy for gastric cancer].

Objective: For gastric cancer patients undergoing total gastrectomy, the esophagojejunal anastomosis is the main site of postoperative anastomotic leakage. How to improve the safety of the esophagojejunal anastomosis is a hot topic. This study evaluated the safety of double and a half layered esophagojejunal anastomosis in total gastrectomy for gastric cancer. Methods: A retrospective cohort study was conducted. Clinical data of 764 gastric cancer patients, who were diagnosed as gastric adenocarcinoma by preoperative gastroscopicbiopsy and were judged to be able to complete R0 resection by imaging examination, in the Affiliated Tumor Hospital of Zhengzhou University (Henan Cancer Hospital) from May 2015 to May 2019 were retrospectively collected and analyzed. two and a half layered esophagojejunal anastomosis was used in the treatment group (295 cases), and the routine anastomosis was used in the control group (469 cases). Postoperative complicating including anastomosis-assisted complications were compared between the two groups. Results: The baseline data of two groups were not significantly different (all P>0.05). All the patients successfully completed the operation. In observation group and control group, the total operative time [(140.7±27.0) minutes vs. (139.6±22.8) minutes], intraoperative blood loss [(200.6±111.0) ml vs. (214.4±114.1) ml], anastomosis time [(20.4±4.3) minutes vs. (19.9±4.6) minutes], time to first flatus [(4.1±1.1) days vs. (4.2±1.1) days], time to fluid diet [(5.4±1.0) days vs. (5.5±0.9) days], time to postoperative nasointestinal tube removal [(9.8±3.2) days vs. (10.0±2.3) days], and postoperative hospital stay [(15.4±6.5) days vs. (15.9±5.6) days] were not significantly different (all P>0.05). Compared to the control group, the treatment group had lower rates of anastomosis-associated complications [1.7% (5/295) vs. 4.7% (22/469), χ(2)=4.768, P=0.029] and anastomotic leakage [1.0% (3/295) vs.3.4% (16/469), χ(2)=4.282, P=0.039]. The differences in the incidence of anastomotic stenosis and anastomotic bleeding were not statistically significant between the two groups (both P>0.05). In the treatment group and control group, rates of total postoperative complication [34.2% (101/295) vs. 32.2% (151/469), χ(2)=0.838, P=0.360] and severe complication [Clavinen-Dindo grade III and above; 4.7% (14/295) vs. 7.2% (34/469), Z=-1.465, P=0.143] were not significantly different as well. Conclusion: Two and a half layered esophagojejunal anastomosis is safe and feasible in total gastrectomy for gastric cancer and can reduce anastomosis-associated complications.

Production of transgenic recloned piglets harboring the human granulocyte-macrophage colony stimulating factor (hGM-CSF) gene from porcine fetal fibroblasts by nuclear transfer.

We used nuclear transfer (NT) to develop transgenic female pigs harboring goat beta-casein promoter/human granulocyte-macrophage colony stimulating factor (hGM-CSF). The expression of hGM-CSF was specific to the mammary gland, and the glycosylation-derived size heterogeneity corresponded to that of the native human protein. Although various cell types have been used to generate cloned animals, little is currently known about the potential use of fibroblasts derived from a cloned fetus as donor cells for nuclear transfer. The developmental potential of porcine cloned fetal fibroblasts transfected with hGM-CSF was evaluated in the present study. Cloned fetal fibroblasts were isolated from a recipient following the transplantation of NT embryos. The cells were transfected with both hGM-CSF and the neomycin resistance gene in order to be used as donor cells for NT. Reconstructed embryos were implanted into six sows during estrus; two of the recipient sows delivered seven healthy female piglets with the hGM-CSF gene (confirmed with PCR and fluorescent in situ hybridization) and microsatellite analysis confirmed that the clones were genetically identical to the donor cells. The expression of hGM-CSF was strong in the mammary glands of a transgenic pig that died a few days prior to parturition (110 d after AI). These results demonstrated that somatic cells derived from a cloned fetus can be used to produce recloned and transgenic pigs.

Experts' Perceptions on China's Capacity to Manage Emerging and Re-emerging Zoonotic Diseases in an Era of Climate Change.

Zoonotic diseases transmitted by arthropods and rodents are a major public health concern in China. However, interventions in recent decades have helped lower the incidence of several diseases despite the country's large, frequently mobile population and socio-economic challenges. Increasing globalization, rapid urbanization and a warming climate now add to the complexity of disease control and prevention and could challenge China's capacity to respond to threats of emerging and re-emerging zoonoses. To investigate this notion, face-to-face interviews were conducted with 30 infectious disease experts in four cities in China. The case study diseases under discussion were malaria, dengue fever and haemorrhagic fever with renal syndrome, all of which may be influenced by changing meteorological conditions. Data were analysed using standard qualitative techniques. The study participants viewed the current disease prevention and control system favourably and were optimistic about China's capacity to manage climate-sensitive diseases in the future. Several recommendations emerged from the data including the need to improve health literacy in the population regarding the transmission of infectious diseases and raising awareness of the health impacts of climate change amongst policymakers and health professionals. Participants thought that research capacity could be strengthened and human resources issues for front-line staff should be addressed. It was considered important that authorities are well prepared in advance for outbreaks such as dengue fever in populous subtropical areas, and a prompt and coordinated response is required when outbreaks occur. Furthermore, health professionals need to remain skilled in the identification of diseases for which incidence is declining, so that re-emerging or emerging trends can be rapidly identified. Recommendations such as these may be useful in formulating adaptation plans and capacity building for the future control and prevention of climate-sensitive zoonotic diseases in China and neighbouring countries.

Advanced remediation of uranium-contaminated soil.

The existing decontamination method using electrokinetic equipment after acidic washing for uranium-contaminated soil requires a long decontamination time and a significant amount of electric power. However, after soil washing, with a sulfuric acid solution and an oxidant at 65 °C, the removal of the muddy solution using a 100 mesh sieve can decrease the radioactivity of the remaining coarse soil to the clearance level. Therefore, only a small amount of fine soil collected from the muddy solution requires the electrokinetic process for its decontamination. Furthermore, it is found that the selective removal of uranium from the sulfuric washing solution is not obtained using an anion exchanger but rather using a cation exchanger, unexpectedly. More than 90% of the uranium in the soil washing solutions is adsorbed on the S-950 resin, and 87% of the uranium adsorbed on S-950 is desorbed by washing with a 0.5 M Na2CO3 solution at 60 °C.

Oxytocin in maternal and fetal blood.

Radioimmunoassayable plasma oxytocin (OT) has been measured in maternal and fetal blood. Simultaneous samples were obtained in maternal forearm venous blood and in umbilical venous and arterial blood in 29 patients at term delivery. In addition, maternal forearm venous blood samples were also obtained 10 minutes prior to delivery. Mean OT level in maternal plasma at delivery was 82 +/- 12 muU/ml, and at 10 minutes prior to delivery the mean OT level was 90 +/- 11 muU/ml. The umbilical arterial plasma OT showed 95 +/- 12 muU/ml and the umbilical vein plasma OT was 60 +/- 10 muU/ml. Oxytocin levels higher in maternal blood than in fetal blood were found with the following incidence: In 51% of samples there was more OT in maternal venous blood than in umbilical arterial blood, and in 84% of samples there was more OT in maternal blood than umbilical vein blood. During the postpartum period, the mean maternal plasma OT was 66 +/- 8 muU/ml for the first day, and 50 +/- 9 muU/ml and 54 +/- 9 muU/ml for the second and third days, respectively. This study indicates that both the fetus and the mother are active producers of oxytocin.