[Comparison of application effects of colonoscopy, fecal immunochemical test and a novel risk-adapted screening approach in colorectal cancer screening in Xuzhou population].

Objective: To compare the application effect of the colonoscopy, fecal immunochemical test (FIT) and novel risk-adapted screening approach in colorectal cancer screening in Xuzhou population. Methods: From May 2018 to April 2019, 4 280 subjects aged 50-74 were recruited from Gulou district, Yunlong district and Quanshan district of Xuzhou. They were randomly assigned to the colonoscopy group (n=863), FIT group (n=1 723) and novel risk-adapted screening approach group (n=1 694) according to the ratio of 1∶2∶2. For the novel risk-adapted screening approach group, after the risk assessment, high-risk subjects were invited to undergo colonoscopy and low-risk subjects were invited to undergo FIT examination. All FIT positive subjects were invited to undergo colonoscopy. Colonoscopy participation rate [(the number of colonoscopies completed/the number of colonoscopies invited to participate)×100%], detection rate of colorectal lesions [(the number of diagnosed patients/the number of colonoscopies completed)×100%], colonoscopy resource load (the number of colonoscopies completed/the number of diagnosed advanced tumors) and FIT resource load in each group were calculated and compared. Results: The age of all subjects was (61±6) years old, including 1 816 males (42.43%). There was no statistically significant difference in the socio-demographic characteristics of the subjects in different screening groups. The colonoscopy participation rate was 22.60% (195/863) in the colonoscopy group, 57.04% (77/135) in the FIT group, and 33.94% (149/439) in the novel risk-adapted screening approach group, respectively. The colonoscopy participation rate was higher in the FIT group than in the colonoscopy group and the novel risk-adapted screening approach group (P<0.001). The colonoscopy participation rate of novel risk-adapted screening group was significantly higher than the colonoscopy group (P<0.001). The detection rates of advanced tumors were 6.67% (13/195), 9.09% (7/77) and 8.72% (13/149), respectively, and the difference was not statistically significant (P>0.05). The colonoscopy resource load (95%CI) was 15 (13-17) in the colonoscopy group, 11 (9-14) in the FIT group and 11 (10-13) in the novel risk-adapted screening approach group, respectively. Among them, the colonoscopy resource load of high-risk individuals in the novel risk-adapted screening approach group was 12 (9-15). FIT resource loads (95%CI) were 207 (196-218) and 88 (83-94) in the FIT group and the novel risk-adapted screening approach group. Conclusion: The combined application of risk-adapted screening approach and FIT may have a good application effect in colorectal cancer screening.

[A case of subacute combined degeneration of spinal cord caused by inhaling laughing gas].

Laughing gas (Nitrogen monoxide) is currently abused due to its low price and easy availability. This article discussed the clinical manifestations of a patient with subacute combined degeneration of the spinal cord caused by inhalation of laughing gas. The patient developed numbness of extremities, unstable walking, and decreased serum vitamin B(12) level. MRI of the cervical spine showed abnormal signals in the lateral and posterior cords of the cervical spinal cord (C2-6) , neuroelectrophysiological examination showed peripheral nerve damage in the extremities. After treatment with vitamin B(12) supplementation, the patient's condition gradually improved. Clinicians diagnose subacute combined degeneration of the spinal cord, especially when the patient has no gastrointestinal disease, diet, malnutrition, etc., they need to carefully inquire about the history of nitrous oxide inhalation to avoid missed diagnosis.

[A comparison between endoscopic CO2 laser cauterization and open neck surgery in the treatment of congenital piriform fistula].

Objective: To compare the efficacy, advantages and disadvantages of endoscopic CO2 laser cauterization (ECLC) and open neck surgery in the treatment of congenital pyriform sinus fistula (CPSF). Methods: From September 2014 to March 2017, 80 cases with confirmed diagnosis of CPSF received initial treatment at Guangdong Provincial People's Hospital were prospectively analyzed, including 34 males and 46 females, aged 18 to 672 (194.17±141.18) months. They were consecutively divided into endoscopic group and open-surgery group, with 40 cases in each group. Both groups of patients received surgical treatment under general anesthesia. The endoscopic group was treated by endoscopic CO2 laser cauterization, and the open-surgery group underwent the following surgery: first, we performed suspension laryngoscopy examination to confirm the presence of fistula in the bottom of the piriform fossa, then open-neck resection of congenital piriform sinus fistula with recurrent laryngeal nerve and/or lateral branch of superior laryngeal nerve anatomy plus partial thyroidectomy were performed. The data between the two groups were compared, including the operative time, intraoperative blood loss, postoperative pain, average length of stay, neck cosmetic scores, complications and cure rates. All patients were followed up in outpatient clinics. Statistical analysis was performed using SPSS 20.0 software. P<0.05 indicates that the difference is statistically significant. Results: All patients were successfully completed the operation. The operative time, intraoperative blood loss, postoperative pain and average length of hospital stay in the endoscopic group were significantly less than those in the open group [(27.4±5.5) min to (105.8±52.5) min, (0.6±0.5) ml to (33.6±41.5) ml, (1.7±0.9) points to (4.6±0.7) points, (5.9±2.9)d to(8.9±3.3)d, t values were-9.400, -5.031, -16.199, -4.293, P values were all<0.01]; The neck cosmetic score in the endoscopy group was significantly greater than that of the open group [(9.9±0.4) against (5.8±0.9) points, t=25.847, P<0.01]. Compared with the open group (15.0%, 6/40), the complication rate of the endoscopic group (7.5%, 3/40) was not statistically significant (χ²=0.50, P>0.05). Three months after the first treatment, the cure rate in the endoscopic group (82.5%, 33/40) was significantly lower than that in the open-neck group (100.0%, 40/40), χ²=5.64, P<0.05. The follow-up time was 12 months after the last treatment. Eighty cases were followed up and none was lost to follow-up. During the follow-up period, the cure rate of the endoscopy group (97.5%, 39/40) was compared with that of the open group (100.0%, 40/40), and the difference was not statistically significant. Conclusions: In the treatment of CPSF, the two-surgical method each has their advantages. Compared with open-neck surgery, ECLC is simpler, repeatable. ECLC has shorter time in operation and hospital stay, less complications, and less postoperative pain and more precise cosmetic results. It could be preferred for the initial treatment of CPSF and relapsed cases after cauterization. But subject to relatively low cure rate of one-time cauterization and uncertain long-term efficacy, it cannot completely replace the open-neck surgery at present.

Sildenafil might impair maternal-fetal immunotolerance by suppressing myeloid-derived suppressor cells in mice.

Myeloid-derived suppressor cells (MDSCs) as an important population of immune cells were found to restrain T cell function, polarize T-helper cells (Th) 1/Th2 toward Th2 response and induce regulatory T cells (Tregs), therefore enhancing the immunotolerance during pregnancy. Sildenafil has been applied for poor endometrial quality in implantation failure patients. Nevertheless, investigations have shown that sildenafil could reduce MDSCs-dependent immunosuppression. Whether sildenafil affects embryo implantation by suppressing MDSCs? To address this question, using the mice model, we investigated the amounts of immune cells in peripheral blood and endometrial cells from control group (CG), sildenafil low-dose group (LDG) and high-dose group (HDG). We found that both treatment groups displayed a marked deficiency in polymorphonuclear (PMN)-MDSCs and Th2 from mice blood and endometrium as compared to these from CG. The frequency of Tregs in endometrium from HDG was lower than those from CG. Th1/Th2 ratio in both periphery and uterus from study groups showed a significant increase as compared to those from CG. By relevance analysis, we found that the level of Tregs positively correlated with the level of PMN-MDSCs, whereas the Th1/Th2 ratio negatively correlated with the frequency of PMN-MDSCs in uterus. Moreover, there was a positive relationship between the amount of blood PMN-MDSCs and endometrial PMN-MDSCs. These results suggest that we should carefully weigh the pros and cons of using sildenafil when applied to patients with poor endometrial receptivity.

[Clinical anatomic study on the segment and adjacent of tract of congenital pyriform sinus fistula].

Objective: To investigate the anatomic tract of congenital pyriform sinus fistula (CPSF). Methods: A total of 90 patients with CPSF undergoing open surgery between August, 2007 and March, 2017 at the Department of Guangdong General Hospital were retrospectively analyzed. Results: The tracts of all the fistulas actually walked far different from those of theoretical ones. A whole fistula may be divided into 4 segments according to adjacent anatomy of CPSF. The posterior inner segment to the thyroid cartilage was initial part of the fistula. It originated from the apex of pyriform sinus, then piercing out of the inferior constrictor of pharynx inferiorly near the inferior cornu of the thyroid cartilage (ICTC), and descended between the lateral branch of the superior laryngeal nerve and the recurrent laryngeal nerve. The ICTC segment was the second part of the fistula, firstly piercing out of the inferior constrictor of pharynx and/or cricothyroid muscle, and then entering into the upper pole of thyroid. The relationship between fistula and ICTC could be divided into three types: type A (medial inferior to ICTC) accounting for 42.2% (38/90); type B (penetrate ICTC) for 3.3% (3/90); and type C (lateral inferior to ICTC) for 54.5% (49/90). The internal segment in thyroid gland was the third part of fistula, walking into the thyroid gland and terminating at its upper pole (92.2%, 83/90) or deep cervical fascia near the upper pole of thyroid (7.8%, 7/90). The lateral inferior segment to thyroid gland was the last part of the fisula, most of which are iatrogenic pseudo fistula, and started from the lateral margin of thyroid gland. Conclusions: CPSF has a complicated pathway. Recognition of the tract and adjacent anatomy of CPSF will facilitate the dissection and resection of CPSF in open surgery.

[Value of modified Killian's method in diagnosis of congenital pyriform sinus fistula].

Objective: To investigate the feasibility and significance of modified Killian(MK) method in the clinical diagnosis of congenital pyriform sinus fistula(CPSF) by electronic laryngoscopy. Methods: The following examinations were performed for 30 suspected cases of CPSF, including the traditional electronic laryngoscopy, MK examination(modified Killian position+ head rotation+ the Valsalva maneuver), barium swallow X-ray(BSX) and CT , and a prospective comparison among them were done. Patients were divided into two groups according to their age: young age group(≤14 years old) and older age group (>14 years old). The results of MK examination from the patients were analyzed and the positive diagnostic rates (PDR) between groups were compared by using χ(2) tests. Results: Sinuses in 20 of 30 patients were depicted from pyriform sinus in BSX, and the PDR was 66.7%(20/30). The PRD of CT was 83.3%(25/30). The presence of air bubbles around the upper lobe of the thyroid gland or at the inferomedial edge of cricothyroid joints, morphological changes of thyroid grand as well as pseudo-fistula formation on lower neck were detected clearly on CT. Comparing to the traditional electronic laryngoscopy, the effect of exposing piriform fossa fistula by MK examination is significant(χ(2)=17.05, P<0.05), with the PDR of 13.3%(4/30) and 76.7%(23/30) respectively. Nevertheless, comparing to BSX and CT, there were no statistically significant differences in the effect to diagnose CPSF (χ(2)=0.31, χ(2)=0.10 respectively, P>0.05). The PDR of MK in older group is significantly higher than younger group(χ(2)=6.68, P<0.05). Conclusions: MK examination can clearly reveal the hypopharyngeal anatomical structure and detect the sinus of CPSF .It could be a safe, feasible, convenient and economical method as an application in preoperative diagnosis and follow-up examination of clinical suspected CPSF.

[Relationship between Work â ¡ type of congenital first branchial cleft anomaly and facial nerve and surgical strategies].

Objective: To investigate the relationship between Work Ⅱ type of congenital first branchial cleft anomaly (CFBCA) and facial nerve and discuss surgical strategies. Methods: Retrospective analysis of 37 patients with CFBCA who were treated from May 2005 to September 2016. Among 37 cases with CFBCA, 12 males and 25 females; 24 in the left and 13 in the right; the age at diagnosis was from 1 to 76 ( years, with a median age of 20, 24 cases with age of 18 years or less and 13 with age more than 18 years; duration of disease ranged from 1 to 10 years (median of 6 years); 4 cases were recurren after fistula resection. According to the classification of Olsen, all 37 cases were non-cyst (sinus or fistula). External fistula located over the mandibular angle in 28 (75.7%) cases and below the angle in 9 (24.3%) cases. Results: Surgeries were performed successfully in all the 37 cases. It was found that lesions located at anterior of the facial nerve in 13 (35.1%) cases, coursed between the branches in 3 cases (8.1%), and lied in the deep of the facial nerve in 21 (56.8%) cases. CFBCA in female with external fistula below mandibular angle and membranous band was more likely to lie deep of the facial nerve than in male with external fistula over the mandibular angle but without myringeal web. Conclusions: CFBCA in female patients with a external fistula located below the mandibular angle, non-cyst of Olsen or a myringeal web is more likely to lie deep of the facial nerve. Surgeons should particularly take care of the protection of facial nerve in these patients, if necessary, facial nerve monitoring technology can be used during surgery to complete resection of lesions.

[Modified rhytidectomy incision and modified Blair incision contrast research in superficial parotid gland tumor resection].

Objective:Evaluate the application value of modified rhytidectomy incision in superficial parotid gland tumor resection.Method:Seventy-one patients with tumor in the superficial parotid were included in this study from January 2012 to January 2015. They all accepted superficial parotidectomy or subtotal superficial parotidectomy. Thirty-six cases used modified rhytidectomy incision and 35 cases used modified blair incision. The data of operative field exposure, operating time, bleeding, the rate of complication, score of patients's satisfaction were recorded and compared between the two groups.Result:There was no statistically significant difference between the two groups in the operative field exposure, operating time and bleeding (P > 0.05). No difference was found between the two groups in the rate of facioplegia, while the rate of insensible earlobe in the modified rhytidectomy incision group was significantly lower than the modified blair incision group (P < 0.05). The score of patient's satisfaction in the modified rhytidectomy incision group was significantly higher than the other group (P < 0.05).Conclusion:The modified rhytidectomy incision provides good exposure and has the advantage of less complication and better cosmetic outcome. It is worthy of wide clinical application.

[Fourth branchial cleft deformity with skin orifice: a series of 10 cases].

Objective: To report rare cases of congenital neck cutaneous sinus with an orifice near the sternoclavicular joint and to investigate their origins and managements. Methods: A total of ten patients with congenital neck cutaneous sinus having an orifice near the sternoclavicular joint treated in the Guangdong General Hospital from January 2010 to June 2015 were retrospectively analyzed. Results: There four boys and six girls, aging from 11 months to 96 months with an average of 33.4 months, and they had a common feature showing a congenital cutaneous sinus with an orifice near sternoclavicular joint. Discharge of pus from the orifice or abscess formation was commonly seen soon after infection. With bacteriological study, staphylococcus aureus was positive in five cases and klebsiella pneumonia in a case. Another orifice of fistula/sinus was not depicted in pyriform with barium swallow X-ray in five cases Ultrasound studies of three cases demonstrated anechoic (i.e., nearly black) and solid-cystic lesion near sternoclavicular joint with posterior acoustic enhancement. Magnetic resonance imaging (MRI) showed isointensity of the lesion on T1 and T2 weighted images with heterogeneous enhancement and a close relationship with sternoclavicular joint. All patients underwent laryngoscopic examination, which showed no orifice of sinus in pyriform at same side. Surgical resection of fistula/sinus was performed in all cases. The lengths of the fistula varied from 5 mm to 22 mm with an average of 11 mm. Postoperative pathological examination showed all specimens were accordance with fistula. No complications were noticed. Recurrence was not observed in the cases by following-up of 6 months to 70 months (median: 33 months). Conclusion: Congenital neck cutaneous sinus with orifice near the sternoclavicular joint maybe a special clinical phenotype of the fourth branchial cleft sinus with skin orifice in cervicothoracic junction. Differential diagnoses between low cervical diseases are required. The curative treatment is a complete excision during inflammatory quiescent period.

[The selective anterior neck dissection for treating children's recurrent thyroglossal duct cysts].

Objective:To evaluate the therapeutic effect of selective anterior neck dissection on the treatment of children's recurrent thyroglossal duct cysts. Method: The clinical data of 28 patients with recurrent thyroglossal duct cysts were retrospectively analyzed. In accordance with the embryologic and anatomic features of thyroglossal duct cysts, different types of selective neck dissection were applied. Enbloc resection principles were applied to extirpate thyroglossal duct cysts,scarrings and inflammatory granuloma during the operation. Result:All the wounds of 28 patients healed primarily without significant complications including dysphagia, paragammacism, injury of hypoglossal nerve and superior laryngeal nerve. No recurrences were found in all 28 cases with a follow-up period of 24 to 72 months(average 46 months). Conclusion:Selective anterior neck dissection is a safe and effective surgical procedure for the radical treatment of children's recurrent thyroglossal duct cysts.

Total synthesis and biological evaluation of (+)- and (-)-Butyl ester of rosmarinic acid.

An efficient method for the synthesis of the natural product (+)-(R)-butyl ester of rosmarinic acid (+)-(R)-1 and its enantiomer ( - )-(S)-1 has been developed by chemical resolution of its phenyl lactic acid precursors 4 with ( - )-menthol. Their antioxidative and anti-tumor activities were evaluated.

Effects of bee venom peptidergic components on rat pain-related behaviors and inflammation.

To identify the active components of honeybee venom in production of inflammation and pain-related behaviors, five major peptidergic subfractions were separated, purified and identified from the whole honeybee venom. Among them, four active peptidergic components were characterized as apamin, mast-cell degranulating peptide (MCDP), phospholipase A(2) (PLA(2))-related peptide and melittin, respectively. All five subfractions were effective in production of local inflammatory responses (paw edema) in rats although the efficacies were different. Among the five identified subfractions, only MCDP, PLA(2)-related peptide and melittin were able to produce ongoing pain-related behaviors shown as paw flinches, while only apamin and melittin were potent to produce both thermal and mechanical hypersensitivity. As shown in our previous report, melittin was the most potent polypeptide in production of local inflammation as well as ongoing pain and hypersensitivity. To further explore the peripheral mechanisms underlying melittin-induced nociception and hypersensitivity, a single dose of capsazepine, a blocker of thermal nociceptor transient receptor potential vanilloid receptor 1, was treated s.c. prior to or after melittin administration. The results showed that both pre- and post-treatment of capsazepine could significantly prevent and suppress the melittin-induced ongoing nociceptive responses and thermal hypersensitivity, but were without influencing mechanical hypersensitivity. The present results suggest that the naturally occurring peptidergic substances of the whole honeybee venom have various pharmacological potencies to produce local inflammation, nociception and pain hypersensitivity in mammals, and among the five identified reverse-phase high pressure liquid chromatography subfractions (four polypeptides), melittin, a polypeptide occupying over 50% of the whole honeybee venom, plays a central role in production of local inflammation, nociception and hyperalgesia or allodynia following the experimental honeybee's sting. Peripheral transient receptor potential vanilloid receptor 1 is likely to be involved in melittin-produced ongoing pain and heat hyperalgesia, but not mechanical hyperalgesia, in rats.

Total enzymatic synthesis of cholecystokinin CCK-5.

This paper describes the enzymatic synthesis of the C-terminal fragment H-Gly-Trp-Met-Asp-Phe-NH2 of cholecystokinin. Immobilized enzymes were used for the formation of all peptide bonds except thermolysin. Beginning the synthesis with phenylacetyl (PhAc) glycine carboxamidomethyl ester (OCam) and H-Trp-OMe by using immobilized papain as biocatalyst in buffered ethyl acetate, the dipeptide methyl ester was then coupled directly with Met-OEt.HCl by alpha-chymotrypsin/Celite 545 in a solvent free system. For the 3+2 coupling PhAc-Gly-Trp-Met-OEt had to be converted into its OCam ester. The other fragment H-Asp(OMe)-Phe-NH2 resulted from the coupling of Cbo-Asp(OMe)-OH with H-Phe-NH2.HCl and thermolysin as catalyst, followed by catalytic hydrogenation. Finally PhAc-Gly-Trp-Met-Asp-Phe-NH2 was obtained in a smooth reaction from PhAc-Gly-Trp-Met-OCam and H-Asp(OMe)-Phe-NH2 with alpha-chymotrypsin/Celite 545 in acetonitrile, followed by basic hydrolysis of the beta-methyl ester. The PhAc-group is removed with penicillin G amidase and CCK-5 is obtained in an overall isolated yield of 19.6%.

Detection of human papillomavirus-16 in ovarian malignancy.

Human papillomavirus is the causal factor for cervical cancer. However, the role of HPV infection in ovarian cancer is unclear. This study aimed to determine the presence of human papillomavirus-16 (HPV-16) in ovarian cancer tissues. Archived human ovarian cancer tissues (N=54 cases, 50 are epithelial cancer, four are nonepithelial cancer) embedded in paraffin blocks were used. Controls are 30 nonmalignant ovarian tissue blocks. In situ hybridisation (ISH) and immunohistochemistry (IHC) were used to detect the presence of HPV-16 and p53 expression. In all, 52 or 36% of the epithelial ovarian tumours detected by ISH or IHC, respectively, were HPV-16 E6 positive. In contrast, only 6.7% of normal ovarian tissues were HPV-16 positive proved by ISH. Human papillomavirus-16 infection was significantly higher in cancer tissues compared to controls with an odds ratio of 16.7 (95% confidence interval [CI]=3.2-71.4, P<0.01). No significant correlation between HPV-16 infection and histological types of cancer was found (P>0.05). p53 gene expression was detected in 42% epithelial ovarian cancers. No correlation between p53 expression and HPV-16 infection was found. The results showed the presence of HPV-16 E6 in ovarian carcinoma, suggesting that HPV infection might play a role in ovarian carcinogenesis.

Human papillomavirus type 16 is an important infectious factor in the high incidence of esophageal cancer in Anyang area of China.

To investigate the potential role of human papillomavirus (HPV) infection in the pathogenesis of esophageal carcinomas in the Anyang area of China, we have evaluated specimens collected by balloon cytology examination from volunteers in two regions with significantly different incidences of esophageal carcinoma. 138 donors were from a village in a county with an esophageal carcinoma (EC) age-adjusted mortality rate of 132x10(5), the remaining 68 were resident in a second village from another county with an EC mortality rate of 52x10(5). Specimens were evaluated using both polymerase chain reaction (PCR) amplification and in situ hybridization (ISH) protocols. PCR results showed that the prevalence of the human papillomavirus type 16 (HPV-16) E6 gene in the high incidence area was 1.9-fold higher than that of the low incidence area (72 and 37%, respectively, P < 0.01). Moreover, the positive rate corresponded with pathology grade. Similar results were obtained with the HPV-16 E7 gene. As the cells undergoing cytopathological progress, the HPV-16 E6 positive rate was increased, in both villages. In contrast to HPV-16 E6 and E7, detection of the HPV L1 gene was consistently lower, and its prevalence decreased with increasing dysplasia grades (P < 0.05). By ISH analyses, the expression rate of HPV-16 E6 in the specimens collected from the high incidence area was 2.2-fold higher than those from the low incidence area (49 versus 22%, respectively; P < 0.05), and transcription of the E6 gene paralleled cytopathology. HPV-18 was also detected in 17 and 15% of the specimens from the high and low incidence areas, respectively, but most of these samples were also simultaneously HVP-16 positive. These results suggest that HVP-16 plays a causative role in the high incidence of esophageal cancer in the Anyang region of CHINA:

Effects of gossypol on the activity of kidney (Na+ + K+)-ATPase and the functions of erythrocyte membrane.

Gossypol extracted from cottonseed oil, reputed to exert contraceptive action in males, may induce a side effect of hypokalemia. The cellular and molecular mechanisms by which gossypol produces hypokalemia are not quite understood. We have examined the inhibitory effect of gossypol on the activity of (Na+ + K+)-ATPase purified from the outer medulla of rabbit kidney, the half maximal inhibitory concentration (IC50) is 6.5 micron. The kinetic studies using this enzyme preparation show that gossypol is noncompetitive with ATP, Mg2+, Na+ and K+ with apparent Ki of 15.0, 13.0, 14.0 and 4.4 micron, respectively. On the other hand, in order to estimate the effects of gossypol on membrane transport of intact cells, we have investigated the effects of gossypol on the activity of (Na+ + K+)-ATPase, membrane integrity and permeability of human erythrocytes. It shows that gossypol inhibited the enzyme activity (greater than 5 micron) and expressed the hemolysis (greater than 50 micron) in vitro in a concentration-dependent manner, and increased the K+-efflux of the cells (10-40 micron). The above effects are antagonized by 1-2% bovine serum albumin. The data demonstrate that gossypol is a specific and potent membrane active agent. These results may be relevant to the in vivo actions of gossypol.

PIP: Hypokalemia has been demonstrated to be the major side effect of gossypol administration for contraceptive purposes; however, the cellular and molecular mechanisms involved in this effect are unknown. This study investigated the effect of gossypol on the activity of (Na+ and K+)-ATPase purified from the rabbit kidney and the functions of erythrocyte membrane. Kinetic findings indicated gossypol is noncompetitive with ATP, Mg2+, Na+, and K+. On the other hand, gossypol inhibited the enzyme activity of (Na+ and K+)=ATPase, expressed the hemolysis in vitro in a concentration-dependent manner, and increased the K+ efflux of the cells. These effects were antagonized by 1-2% serum bovine albumin. These findings demonstrate that gossypol is a specific and potent membrane active agent capable of injuring the cell membrane.