Securing the surgical field for mobilization of right-sided colon cancer using the duodenum-first multidirectional approach in laparoscopic surgery.

BACKGROUND: The aim of this study was to compare the short-term outcomes of the duodenum-first multidirectional approach (DMA) in laparoscopic right colectomy with those of the conventional medial approach to assess its safety and feasibility. METHODS: This retrospective study enrolled 120 patients who had laparoscopic surgery for right-sided colon cancer in our institution between April 2013 and December 2019. Fifty-four patients underwent colectomy using the multidirectional approach; among these, 20 underwent the DMA and 34 underwent the caudal-first multidirectional approach (CMA). Sixty-six patients underwent the conventional medial approach. Complications within 30 days of surgery were compared between the groups. RESULTS: There were 54 patients in the multidirectional group [29 females, median age 72 years (range 36-91 years)] and 66 in the medial group [42 females, median age 72 years (range 41-91 years)]. Total operative time was significantly shorter in multidirectional approach patients than conventional medial approach patients (208 min vs. 271 min; p = 0.01) and significantly shorter in patients who underwent the DMA compared to the CMA (201 min vs. 269 min; p < 0.001). Operative time for the mobilization procedure was also significantly shorter in patients who underwent the DMA (131 min vs. 181 min; p < 0.001). Blood loss and incidence of postoperative complications did not differ. In 77 patients with advanced T3/T4 tumors, the DMA, CMA, and conventional medial approach were performed in 13, 21, and 43 patients, respectively. Total operative time and operative time of the mobilization procedure were significantly shorter in patients undergoing DMA. Blood loss and incidence of postoperative complications did not differ. R0 resection was achieved in all patients with advanced tumors. CONCLUSIONS: The DMA in laparoscopic right colectomy is safe and feasible and can achieve R0 resection with a shorter operative time than the conventional medial approach, even in patients with advanced tumors.

Atrophic change of the abdominal rectus muscle significantly influences the onset of parastomal hernias beyond existing risk factors after end colostomy.

PURPOSE: To investigate optimal risk factors, including atrophy of the abdominal rectus muscle (ARM) for postoperative parastomal hernia (PH) in patients who underwent end colostomy at left lower quadrant. METHODS: This single-institution retrospective study included 91 patients who underwent end colostomy between April 2004 and December 2015. The surgical and long-term outcomes among patients with or without PH were collected and compared. RESULTS: Altogether, 22 (24.2%) patients had a PH including 15 (68.2%) patients with a simultaneous incisional hernia. Univariate analysis showed that older patients (71 ± 11.9 vs. 64 ± 12.2 years, p = 0.03) and those with higher body mass index (BMI) (23.8 ± 3.8 vs. 20.9 ± 3.3 kg/m2, p < 0.001) had a statistically significant relation with having PHs. Relative atrophy of left abdominal rectus muscle was more frequently found in patients with PH (ratio of left side/right side; caudal level and medial side: 0.66 vs. 0.92, p < 0.01, caudal level and lateral side: 0.95 vs. 1.03, p = 0.04). Multivariate analysis revealed that BMI > 25 kg/m2 [odds ratio (OR) 9.05, 95% confidence interval (CI) 2.06-39.76, p = 0.003] and atrophy of the left lower medial portion of the abdominal rectus muscle (OR 12.85, 95% CI 2.49-66.39, p = 0.002) were independent risk factors for PHs. Neither the laparoscopic approach nor the extraperitoneal route of the colostomy was proven to correlate with a lower rate of PHs. CONCLUSIONS: High BMI and atrophic change of ARM were significantly associated with PH development. Surgical techniques for prevention of atrophic change of ARM are expected to reduce the incidence of PHs.

High birthweight is associated with increased prevalence of dental caries in Japanese children.

OBJECTIVE: We determined the prevalence of dental caries in 3-year-old Japanese children in a cross-sectional study and analysed its associations with birthweight, gestational age and birthweight for gestational age among the study subjects. METHODS: Study subjects were 6327 children. Their parents or guardians completed our study questionnaire with information on birth conditions and oral examinations taken from their Maternal and Child Health Handbooks, as documented by medical personnel at the hospital, clinic or public health centre. Children with one or more primary teeth that had either decayed or been filled were categorized as having caries. RESULTS: The prevalence of dental caries was 14.7%. We found a significant association between high birthweight (≥4000 g) and a higher prevalence of caries, compared with normal birthweight (2500-3999 g). Low birthweight (<2500 g) was not associated with dental caries prevalence. In addition, no measurable associations between gestational age or birthweight for gestational age and caries prevalence were observed. CONCLUSIONS: Our findings indicate that high birthweight might increase the likelihood of dental caries in children.

Thermo-, photo-, and mechano-responsive liquid crystal networks enable tunable photonic crystals.

Tunable photonic crystals exhibiting optical properties that respond reversibly to external stimuli have been developed using liquid crystal networks (LCNs) and liquid crystal elastomers (LCEs). These tunable photonic crystals possess an inverse opal structure and are photo-responsive, but circumvent the usual requirement to contain dye molecules in the structure that often limit their applicability and cause optical degradation. Herein, we report tunable photonic crystal films that reversibly tune the reflection peak wavelength under thermo-, photo- and mechano-stimuli, through bilayering a stimuli-responsive LCN including azobenzene units with a colourless inverse opal film composed of non-responsive, flexible durable polymers. By mechanically deforming the azobenzene containing LCN via various stimuli, the reflection peak wavelength from the bilayered film assembly could be shifted on demand. We confirm that the reflection peak shift occurs due to the deformation of the stimuli-responsive layer propagating towards and into the inverse opal layer to change its shape in response, and this shift behaviour is repeatable without optical degradation.

The pga gene cluster in Aggregatibacter actinomycetemcomitans is necessary for the development of natural competence in Ca(2+) -promoted biofilms.

Natural competence is the ability of bacteria to incorporate extracellular DNA into their genomes. This competence is affected by a number of factors, including Ca(2+) utilization and biofilm formation. As bacteria can form thick biofilms in the presence of extracellular Ca(2+) , the additive effects of Ca(2+) -promoted biofilm formation on natural competence should be examined. We evaluated natural competence in Aggregatibacter actinomycetemcomitans, an important periodontal pathogen, in the context of Ca(2+) -promoted biofilms, and examined whether the pga gene cluster, required for bacterial cell aggregation, is necessary for competence development. The A. actinomycetemcomitans cells grown in the presence of 1 mm CaCl2 exhibited enhanced cell aggregation and increased levels of cell-associated Ca(2+) . Biofilm-derived cells grown in the presence of Ca(2+) exhibited the highest levels of natural transformation frequency and enhanced expression of the competence regulator gene, tfoX. Natural competence was enhanced by the additive effects of Ca(2+) -promoted biofilms, in which high levels of pga gene expression were also detected. Mutation of the pga gene cluster disrupted biofilm formation and competence development, suggesting that these genes play a critical role in the ability of A. actinomycetemcomitans to adapt to its natural environment. The Ca(2+) -promoted biofilms may enhance the ability of bacteria to acquire extracellular DNA.

Changes in cerebral oxygenation in children undergoing surgical repair of ventricular septal defects.

There have been few published studies on changes in cerebral oxygenation during paediatric cardiac surgery as measured by conventional near-infrared spectroscopy. We studied changes in cerebral oxygenation in 16 children undergoing surgical repair of ventricular septal defects. Fifteen of the patients showed similar patterns of changes: brain tissue concentrations of oxyhaemoglobin decreased significantly during cardiopulmonary bypass, whereas there was no significant change in brain tissue concentrations of deoxyhaemoglobin. In the remaining patient, who suffered decreased blood flow to the lower body during surgery, the pattern of changes was different to that of the other subjects. This patient suffered postoperative respiratory and renal failure. This study suggests that conventional near-infrared spectroscopy may be useful for clinical monitoring during ventricular septal defect repair.

Effects of mild and moderate hypothermia on apoptosis in neuronal PC12 cells.

BACKGROUND: There is still a possibility that mild hypothermic therapy may be useful as a neuroprotective tool during the intraoperative period, although the mechanism of cerebral protection by mild hypothermia is not well understood. We hypothesized that mild hypothermia may be protective against cerebral ischaemia by inhibiting post-ischaemia apoptosis. In this study, we used serum-deprived PC12 cells as the neuronal apoptotic model and examined the direct effects of mild and moderate hypothermia. METHODS: Apoptosis was induced by depriving the cell culture medium of serum, which is one of the most representative methods to induce apoptosis, but not necrosis, in PC12 cells. Effects of mild (35 and 33 degrees C) and moderate (31 and 29 degrees C) hypothermia on apoptosis were evaluated. Cytotoxicity (lactate dehydrogenase leakage) and the percentage of apoptotic cells (calculated by flow cytometry with propidium iodide) were evaluated 4 days after induction of apoptosis. As a control, cells without induction of apoptosis were incubated under the same conditions as the apoptosis group. RESULTS: Without induction at 37 degrees C, cytotoxicity and the percentage of apoptotic cells were over 60 and 90%, respectively. At each temperature examined below 35 degrees C, significant decreases in cytotoxicity and the percentage of apoptotic cells were observed. Mean cytotoxicity at 31 and 29 degrees C was 50.2 (SD 4.2)% and 47.9 (4.4)%, respectively. The percentage of apoptotic cells at 31 and 29 degrees C was 42.5 (7.4)% and 36.5 (7.3)%, respectively. In the control group, cytotoxicity and the percentage of apoptotic cells were significantly higher at 29 degrees C than at 37 degrees C. CONCLUSIONS: Mild and moderate hypothermia (29-35 degrees C) inhibited apoptosis, although hypothermia below 30 degrees C may induce apoptosis in intact cells.

Posterior sagittal anorectoplasty for failed imperforate anus surgery: lessons learned from secondary repairs.

PURPOSE: The aim of this study was to evaluate secondary operations using a posterior sagittal approach in patients with fecal incontinence and impaction after primary repair of anorectal malformations. METHODS: Twenty patients (14 boys, 6 girls) who had previous failed surgery for imperforate anus underwent secondary operations. The indications for surgery included fecal incontinence (n = 16) and fecal impaction (n = 4). Patients ranged in age from 2 to 30 years (mean, 11 years), with 4 over the age of 20 years. The primary procedures included abdominosacroperineal (n = 7), sacroperineal (n = 10), and perineal (n = 3) pull-throughs. At surgery, none of the patients underwent a diverting colostomy. The rectum was mobilized from the surrounding structures through a posterior sagittal approach. The surgical findings included anteriorly displaced anus (n = 17), laterally displaced anus (n = 3), mesenteric fat surrounding the rectum (n = 4), mega-rectosigmoid (n = 2), and others (n = 3). The rectum underwent reconstruction, which involved relocation of the rectum and anus to surround them with the muscle complex. RESULTS: Patients underwent follow-up for periods ranging from 8 months to 6 years after surgery (mean, 3 years). To evaluate the functional results, fecal continence scores (Templeton and Ditesheim) were calculated for incontinent patients. Of the 16 incontinent patients, 12 achieved continence and 4 some improvement. Of the 4 patients with fecal impaction, 2 achieved daily voluntary bowel movement, whereas the other 2 have mild constipation and need occasional enemas. CONCLUSIONS: Our study suggests that (1) a secondary operation through a posterior sagittal approach can restore fecal continence and is efficacious even in adolescents and adults and (2) a posterior sagittal procedure can be safely performed without a diverting colostomy.

Management of cholelithiasis in combination with cardiovascular surgery.

A retrospective review of the perioperative management of patients with cardiovascular surgical disorders and cholelithiasis was conducted, and the surgical strategies employed are discussed. Between 1988 and 1998, 18 patients having cardiovascular surgical disorders underwent cholecystectomy. These patients were divided into three groups: group I, given a one-stage operation (n = 9); group II, given a two-stage operation (n = 3); and group III, given cholecystectomy during follow-up after cardiovascular surgery (n = 6). In group I, a median laparotomy was adopted for patients with an abdominal aortic aneurysm (AAA) to allow both disorders to be treated through the same incision, whereas a right subcostal approach was employed to separate the incisions for patients who underwent cardiac operations. In group II, one patient underwent cholecystectomy before cardiac surgery, and two patients underwent cholecystectomy for postoperative cholecystitis after cardiovascular operations. One patient from group II and all from group III were on preoperative anticoagulant therapy, two of whom underwent laparoscopic cholecystectomy. No fatal complications such as prosthetic infection, intraperitoneal hemorrhage, or cerebral attack were encountered. In conclusion, we consider that performing cholecystectomy during AAA repair may be safe and prevents the risk of postoperative cholecystitis; it is preferable to treat cholelithiasis coexisting with cardiac disorders concomitantly with or before cardiac operations; and laparoscopic cholecystectomy can be safely performed under anticoagulant therapy.

Combined resection of the thoracic esophagus and thoracic descending aorta.

We conducted combined resection of the thoracic esophagus and thoracic descending aorta in 2 patients, one with advanced esophageal cancer with aortic invasion and the other aortoesophageal fistula caused by a false aortic aneurysm. Combined resection of esophageal tumor and adjacent involved organs was conducted in 14 patients with A3:T4 esophageal cancer but none survived 3 years and resecting tumor-invaded organs did not improve patient survival. One major problem of combined resection of the esophagus and aorta is contamination of the posterior mediastinum. In 1 patient, 2-stage surgery for the esophagus and in situ aortic replacement was conducted to reduce operative risk and avoiding infection of the prosthetic vascular graft. With thoracic descending aortic aneurysm adjacent to the esophagus on the increase, cardiovascular surgeons should prepared to undertake combined resection of both the aorta and esophagus.

Laparoscopic orchiopexy of intraabdominal undescended testis associated with congenital diaphragmatic hernia.

Laparoscopy is an advantageous method for the repair of intraabdominal undescended testis since both an abdominal exploration and vascular elongation can be effectively performed by laparoscopic assistance. A 3-year-old boy and a 1-year-old boy complaining of unilateral nonpalpable left testes were observed following previous congenital diaphragmatic hernia repairs on the day of birth. In these operations, a laparoscopic working sheath was inserted through a small supraumbilical incision. On each boy, a laparoscopically intraabdominal testis was found close to the left internal inguinal ring. In addition, a 10-mm trocar port was placed in the right lower abdominal quadrant and a 5-mm port was placed in the left lower quadrant. For the purpose of orchiopexy, the left testicular vessels were isolated over their full length. The left side of the testis was pulled through the inguinal ring to an inguinal canal divided by the abdominal wall, and then was retracted into the scrotum. The internal ring was thereafter closed externally by the fascia transversalis. Both patients are doing well, with no testicular atrophy or inguinal hernia for 1 and 2 years, respectively, after the above operations.

Antibodies against Helicobacter pylori were detected in the cerebrospinal fluid obtained from patients with Guillain-Barré syndrome.

We examined the antibodies against Helicobacter pylori proteins in the cerebrospinal fluid (CSF) of 7 patients with Guillain-Barré syndrome (GBS). Crude H. pylori antigens, fractionated heat shock protein (HSP), and urease B (UB) from H. pylori antigens were separated by SDS-PAGE. With Western blot analysis, four of seven CSF samples had several IgG antibodies against H. pylori proteins, including HSP and UB. No cross reactivity against Campylobacter jejuni was observed. These antibodies may be involved in the immune responses of patients with GBS.

A new artificial placenta with a centrifugal pump: long-term total extrauterine support of goat fetuses.

PURPOSE: We tried long-term total extrauterine support of goat fetuses at high pump flow, which was pulsatile and synchronized with the cardiac cycle and at low oxygen tension in the umbilical artery and vein by use of the new artificial placenta. METHOD: This system consisted of an arteriovenous extracorporeal membrane oxygenation using umbilical artery and vein and a thermoregulated water bath. Five goat fetuses (125 +/- 0.7 days of gestation, 2.0 +/- 0.9 kg) were incubated in lactated Ringer's solution. Mean pump flow rate ranged from 113 +/- 16 to 193 +/- 13 ml/min/kg, and umbilical arterial oxygen tension was maintained at 20 +/- 3 to 23 +/- 5 mm Hg for five fetuses. RESULT: Blood gas analysis echocardiogram showed that fetal circulation and sufficient oxygen consumption could be maintained, and fetal extrauterine support conditions were made as similar as possible to physiologic circulatory conditions. We achieved long-term extrauterine support of goat fetuses up to 237 hours (mean 137 +/- 58 hours). CONCLUSION: We believe that this system can be used for experimental models of the fetus and will come into clinical application for fetal extrauterine support systems and backup systems for fetal operations.

Arterio-venous extracorporeal membrane oxygenation of fetal goat incubated in artificial amniotic fluid (artificial placenta): influence on lung growth and maturation.

PURPOSE: The authors attempted to achieve extrauterine support of goat fetuses using arteriovenous extracorporeal membrane oxygenation (A-V ECMO) via umbilical vessels, incubated in a warm bath. They hypothesized that this extrauterine support system affected both the lung growth and maturation of goat fetuses. METHODS: Four goat fetuses at about 125 days' gestation (term, 150 days) were placed in this fetal ECMO system. Their four twin fetuses with similar body weights were harvested and examined for baseline data before ECMO (pre-ECMO data). The mean duration of A-V ECMO was 138.8+/-66.9 hours (range, 87 to 237 hours). Tracheal ligation was performed on all four fetuses to prevent the efflux of fetal tracheal fluid and to collect a sample of tracheal fluid daily. The surfactant and electrolytes of the tracheal fluid were analyzed in pre-ECMO (twin fetuses) and during ECMO. The surfactant of lung tissue, and lung weight were analyzed in pre-ECMO (twin fetuses) and after ECMO. Plasma cortisol and T3 levels were also assayed as hormonal factors that affected lung maturation in pre-ECMO and during ECMO. RESULTS: The phospholipid, phosphatidylcholine, and lecithin-sphingomyelin ratio of the tracheal fluid on day 5 during ECMO (15.0+/-7.1 mg/dL, 53.4+/-26.5%, and 6.2+/-7.1) were elevated above pre-ECMO (10.0+/-4.6 mg/dL, 43.0+/-0.6%, and 4.0+/-2.9), but there were no significant differences. The phosphatidylcholine and disaturated phosphatidylcholine of the lung tissue after ECMO were 72.3+/-15.4 mg/g and 19.2+/-8.2 mg/g, which were significantly higher than pre-ECMO (53.7+/-13.9 mg/g and 11.6+/-4.1 mg/g). The Cl- and K+ of the tracheal fluid were 123.5+/-6.2 mEq/L and 3.7+/-0.7 mEq/L on day 1 during ECMO, which were significantly lower than pre-ECMO (141.8+/-2.9 mEq/L and 6.8+/-1.1 mEq/L), but they then recovered to pre-ECMO levels. The wet and dry lung weights after ECMO were 87.8+/-18.0 g and 6.3+/-1.9 g, which were significantly higher than pre-ECMO (49.3+/-5.9 g and 4.2+/-1.3 g). Plasma cortisol levels and T3 levels during ECMO were significantly higher than pre-ECMO. Electron microscopy demonstrated a higher increase of mature type 11 cells in the lungs after ECMO than pre-ECMO. CONCLUSION: This fetal A-V ECMO system in the bath showed a production of surfactant, the maintenance of ion transport by the pulmonary epithelium, an increase in lung weight, and an increase in mature type II cells, resulting in lung growth and maturation.

Ligation of medically refracted patent ductus arteriosus (PDA) in an extremely low body weight premature infant.

Medically refracted patent ductus arteriosus (PDA) in an extremely low birth weight (ELBW) preterm (gestation 24 weeks 2 days) infant was successfully ligated under general anesthesia in the neonatal intensive care unit (NICU). Pharmacological agents are more effective to close PDA in preterm infants than in full-term infants, although within 48 h three doses of indomethacin were not sufficient to close PDA in this case. At the age of 69 h the infant developed severe symptoms including bradycardia, systemic hypotension, pulmonary hypertension, diastolic steal (reverse distal aorta flow velocity), and anuria. A PDA ligation was thus performed surgically at 72 h of age. General anesthesia and surgical stress were tolerated by this 531 g infant. Postoperatively all symptoms improved dramatically and the general conditions were stable. On the 38th day the endotracheal tube was extubated and on the 50th day nasogastric milk feeding was started. The oxygen supply was weaned on the 78th day. Growth and development until 6 months were within the normal range of very low birth weight infants. A surgical ligation as early as possible in medically refracted PDA in an ELBW infant is thus considered to be a safe and effective treatment. It prevents the development of further complications of cardiopulmonary vascular problems. Color Doppler echocardiography can reliably measure the PDA size, flow velocity, and hemodynamic changes of persistent PDA, even in tiny infants.

[Development of extracorporeal membrane oxygenation for neonates with severe respiratory failure].

Extracorporeal membrane oxygenation (ECMO) is one of the most highly developed artificial organ treatment of the last decade. Especially for severe neonatal respiratory failure, ECMO has become standard treatment in Japan following the same pattern as in the USA. In the USA, more than 12,000 infants have been registered for ECMO treatment by the Extracorporeal Life Support Organization (ELSO), and their total survival rate is above 80%. Recently, to avoid ligating the carotid artery, most neonates who required ECMO have been supported by a veno-venous (V-V) bypass using a double-lumen catheter via the right internal jugular vein into the right atrium. To prevent bleeding complications, the introduction of Nafamostat Mesilate and the development of a heparin-coated system would be advantageous. Progresses in these instruments and perfusing techniques might enlarge the indications of ECMO. We performed an experiment on fetus ECMO as artificial placenta. The fetuses were incubated for 10-237 hours by A-V ECMO using a centrifugal pump successfully and maturation of the lung was revealed. In the future the fetus ECMO could be introduced clinically as a back-up system for fetal surgeries and incubation for extra-premature infants.

[A case of intrathoracic goiter].

Intrathoracic goiter is an uncommon conditional lesion. A case of intrathoracic goiter in a 66-year-old woman is herein described. Her chief complaint was anterior chest opplession. A computed tomographic scan and magnetic resonance imaging (MRI) revealed intrathoracic goiter pressed the trachea to the right side. The tumor was safety and completely took by collar incision without thoracotomy. Histologically, the mass was diagnosed the adenomatous goiter. In this case, MRI was very useful to be determined the surgical approach.

[Operative corrections of funnel chest depend on age group].

The methods of correcting funnel chest are various and many. It's necessary to select the proper method depending on the age group. For children, sternal elevation by Ravitch's procedure produces to better results without prosthesis. For adolescent patients, the elevated sternum can be maintained by Kirschner's wires. Furthermore, adult patients have severe chest wall deformities with calcificated costal cartilage. The methods sternal elevation methods cause an unsatisfactory by postoperative appearance for adult patients with funnel chest. Two adult patients, 20 and 48-year-old men, underwent the sternal turnover methods with complete sternal blood supplies. The procedures of the new method turn over the sternal body crossing bilateral internal thoracic vessels and abdominal rectal muscles. No chest wall deformities were seen and the patency of internal thoracic arteries and superior epigastric arteries was revealed by postoperative arteriography.

Quantitative detection of secretory immunoglobulin A to Helicobacter pylori in gastric juice: antibody capture enzyme-linked immunosorbent assay.

Helicobacter pylori is a major etiologic agent in gastroduodenal disorders. In this study, immunoglobulin A (IgA) antibodies to H. pylori were estimated in serum and gastric juice specimens from patients with gastritis and peptic ulcers using antibody capture enzyme-linked immunosorbent assays (ACELISAs). The antibody titers of the ACELISAs are independent of the antibody concentration and reflect the ratio of H. pylori-specific IgA to total IgA. The ratio is stable, although the antibody concentration fluctuates in gastric juice. Using the ACELISAs it was possible to evaluate quantitatively not only serum IgA (SR-IgA) antibodies but also secretory IgA (SC-IgA) antibodies in gastric juice. There were significant differences between the patients and control group in the SR-IgA and SC-IgA ACELISAs. Furthermore, the ACELISAs made it possible to compare between SR-IgA antibodies in serum and SC-IgA antibodies in gastric juice. In all patients, the ratios of H. pylori-specific IgA were higher in gastric juice than in serum. These results suggest that H. pylori SC-IgA antibodies are mainly produced by the local immune response in the gastric mucosa. Our studies indicate that ACELISA is well suited for the analysis of local immune response in mucosa.

Detection and identification of cagA of Helicobacter pylori by polymerase chain reaction.

AIM: To investigate cagA, which is linked to vacuolating cytotoxin activity of Helicobacter pylori, using molecular techniques. MATERIALS AND METHODS: A polymerase chain reaction method was used to detect cagA from clinical isolates of H. pylori. H. pylori strain diversity was examined by DNA restriction fragment length polymorphism (RFLP) patterns with cagA as a probe. RESULTS: The detection rate of the cagA products was significantly higher in strains from gastric ulcer patients than in those of chronic gastritis patients (78.9 versus 56.0%; P < 0.05), and RFLP patterns were different between gastric ulcer and gastric cancer strains. CONCLUSIONS: A polymerase chain reaction method established for the detection of cagA proved to be rapid and useful. Analysis of cagA may therefore be a useful genetic technique for the study of strain diversity.