Correlation of lower esophageal mucosal ring and lower esophageal sphincter pressure

We assessed the relationship of lower esophageal sphincter pressure (LESP) to presence and absence of lower esophageal mucosal ring (LEMR) in 66 patients to determine if the LEMR was more likely related to prolonged sphincter hypotension. This potential relationship is of interest because LEMR may be due to reflux esophagitis. Each patient had radiographic and manometric studies, and both examinations were done within one week of each other. The mean LESP in patients with LEMR was 23.8 mm Hg (range 4.2-64 mm Hg) compared to 28.7 mm Hg (range 8-59 mm Hg) in patients without LEMR; the difference was not statistically significant. Patients with LEMR were also divided into three subgroups according to the diameter of the rings (< or = 13 mm, 14-19 mm, > or = 20 mm). There was no significant relationship between the caliber of LEMR and LESP (P > 0.05). Presence of LEMR did not affect the amplitude or duration of primary esophageal peristalsis. These results do not support a relationship between LEMR and prolonged LESP hypotension or abnormal esophageal motility. However, other pathogenetic mechanisms involved in producing reflux esophagitis not related to prolonged sphincter hypotension were not studied.

Globus pharyngeus: radiographic evaluation and 24-hour pH monitoring of the pharynx and esophagus in 22 patients

PURPOSE

The authors correlated the radiographic evaluation and 24-hour pH monitoring of the pharynx and the esophagus in patients with globus pharyngeus.

MATERIALS AND METHODS

Radiographic examination of the pharynx of 22 patients (13 women and nine men, aged 23-73 years [mean, 47 years]) included videofluoroscopy and static radiography. Twenty-four-hour double-probe pH monitoring of the pharynx (abnormal, pH < 4) and esophagus (abnormal, 6% or more total acid exposure) was performed in all patients.

RESULTS

Radiographic results were normal in 17 patients; results were abnormal in five, with four having pharyngeal dysfunction and one showing a persistent cricopharyngeal impression. Zenker diverticulum was not seen. Results at pH monitoring of the pharynx and esophagus were normal in 20 and 18 of the 22 patients, respectively. In four of five patients with abnormal radiographic studies of the pharynx, results of pharyngeal pH monitoring were normal.

CONCLUSION

Most patients with globus pharyngeus had normal results at pH monitoring and radiographic examination of the pharynx.

The internationalization of the American Journal of Roentgenology: 1980-1992

OBJECTIVE

The purpose of this study was to determine whether significant changes have occurred in the number of foreign articles published in the American Journal of Roentgenology since 1980.

MATERIALS AND METHODS

A total of 3398 articles published in AJR during two 3-year periods (1980-1982 and 1990-1992) were classified by type, subject, radiologic technique, organ system, and national origin. Additionally, 2865 manuscripts submitted to AJR from 1990 to 1992 were analyzed to determine the probability of manuscript acceptance based on country of origin.

RESULTS

From 1980 to 1992, 158 (10%) of 1610 articles published in AJR originated from institutions outside the United States. By 1990-1992, international articles accounted for 441 (25%) of 1788 published papers (p < .00001). Although the total number of published articles from most nations increased during the decade, Korea, Japan, and Germany made the largest advances. International contributions in the 1990s were most numerous in the following areas: adult radiology, abdominal/gastrointestinal imaging, pulmonary/thoracic imaging, sonography, and interventional radiology. Notwithstanding these trends, manuscripts submitted from international sources are somewhat less likely to be accepted for publication than those originating from the United States (acceptance rate for major papers 27% vs 33%, p = .01).

CONCLUSION

The American Journal of Roentgenology is becoming increasingly internationalized, with Korea, Japan, and Germany making particularly striking advances in the past decade.

Skull-base foramina of the middle cranial fossa: reassessment of normal variation with high-resolution CT

PURPOSE

To evaluate by means of high-resolution CT the anatomic variations of the middle cranial fossa foramen.

METHODS

We examined 123 CT studies of the temporal bone in patients with no evidence of disease that might alter foraminal anatomy. A checklist of known variants and suspected structures was used as each case was systematically examined for the presence or absence of these foramina; variations in size, shape, and location; and relationship of structures to each other. Inclusion criteria were established to eliminate error.

RESULTS

The foramen rotundum had a constant appearance. We identified the inferior rotundal canal in 16% of patients and the lateral rotundal canal in 8%. The foramen of Vesalius was present, at least unilaterally, in 80% of our cases. Asymmetry of the foramen of Vesalius did not indicate disease in our patient group. We did not find an inverse relationship between the size of the foramen of Vesalius and that of the ipsilateral foramen ovale. We found variations in the size and shape of the foramen ovale and its confluence with the foramen spinosum (n = 2) and the foramen of Vesalius (n = 8). We did not find an inverse relationship between the size of the foramen ovale and that of the foramen spinosum. The canaliculus innominatus for the lesser superficial petrosal nerve was identified in 16.3% of our patients. Variations of the foramen spinosum that we found include a medial bony defect (26.8%) and absence (3.2%).

CONCLUSION

Although it is unlikely that well-formed foramen will be misinterpreted as diseased, it is nonetheless important to recognize foraminal variants and associated neurovascular anatomy.

The study of anticardiolipin antibodies and interleukin-6 in cerebrospinal fluid and blood of Chinese patients with systemic lupus erythematosus and central nervous system involvement

Anticardiolipin (ACL) antibodies and interleukin-6 (IL-6) in cerebrospinal fluid (CSF) may be involved in the mechanism of lupus patients with central nervous system (CNS) involvement. ACL antibodies of 3 isotypes and IL-6 were measured in paired CSF and serum samples from 14 lupus patients with CNS involvement, 5 lupus patients without CNS involvement and 7 patients with non-inflammatory neurological diseases. ACL antibodies, IgG and IgM isotypes, and IL-6 were significantly increased in CSF from lupus patients with CNS involvement as compared with other 2 groups of patients. Both ACL antibodies and IL-6 decreased after neurological activity subsided. These results suggest increased ACL antibodies and IL-6 in CSF are involved in immune responses within CNS in lupus patients. Quantitation of CSF ACL antibodies may be helpful in evaluating neurological activity of lupus patients with CNS involvement.

Cytosolic acetylation of sulfamethazine decreases hepatic release of ketone bodies in vivo in fasting rats

The effect of sulfamethazine (SMZ) on ketogenesis was studied in this report. SMZ, a sulfonamide metabolized by cytosolic acetylation in liver, was intraperitoneally injected (2 mmol/kg) to ketamine-anesthetized, overnight-fasted rats. Ketogenesis was measured by the Fick principle from the transhepatic (A-V) gradients of acetoacetate (AcAc) and D-beta-hydroxybutyrate (beta-OHB). Prior to SMZ injection, A-V gradient of ketone bodies (KB) (AcAc + beta-OHB) was -1.38 mM, indicating release from the liver. After SMZ injection, the release of KB decreased rapidly, maintaining at a level approximately 50% less than controls throughout the 2-h experimental period. Plasma concentrations of AcAc and beta-OHB also decreased. In contrast, plasma concentrations and trans-hepatic gradients of free fatty acids (FFA) were not significantly affected. Our results thus indicate that SMZ acetylation in liver mobilizes acetyl CoA from mitochondria. Decreased hepatic ketogenesis limits the availability of KB and may thus affect energy metabolism in the extrahepatic tissues. The incomplete inhibition on ketogenesis may indicate compartmentation of acetyl CoA in liver mitochondria.

Therapeutic ERCP: spectrum of procedures performed in 60 consecutive patients

Therapeutic applications of endoscopic retrograde cholangiopancreatography (ERCP) have increased dramatically, and endoscopic sphincterotomy (ES) is the cornerstone of these techniques. Indications include treatment of retained biliary duct stones, papillary stenosis, benign and malignant strictures, and acute cholangitis and pancreatitis. We reviewed our recent experience to assess the spectrum of procedures done and their results. Medical records and radiographic examinations in 60 consecutive patients undergoing therapeutic ERCP were studied. Patients were placed into one of three treatment groups; Group 1, ES alone (N = 21); Group 2, ES plus stone retrieval (N = 15); and Group 3, ES plus stent placement (N = 24). In Group 1, all of eight patients with ductal stones had spontaneous passage. In 11 patients with papillary stenosis, nine had relief of symptoms following ES. Two patients with pancreatitis improved after ES. In Group 2, all 15 patients with ductal stones had successful retrieval. In Group 3, patients were treated for biliary stricture alone (4), retained stones (7), pancreatitis (5), neoplasms (6) and papillary stenosis (2). In these 24 patient, 21 (88%) were treated successfully or had palliation of their symptoms. In our series, a wide variety of therapeutic applications of ERCP was used to manage simple and complex biliary disease. ES alone or in combination with other techniques was done in all patients. Overall, 55 (92%) of 60 interventional procedures were successful as defined by removal of stones and relief or palliation of symptoms.

Toxic effects of linear alkylbenzene sulfonate on the tiger prawn, Penaeus monodon

The toxic effects of linear alkybenzene sulfonate (LAS) on the larvae and juveniles of tiger prawn Penaeus monodon were tested. The 24-hr LC50 values of LAS were 0.06, 0.10, and 3.11 ppm for the zoea 2nd substage, mysis 2nd substage (M2), and postlarva 12th substage (PL12) of the tiger prawn, respectively. The 48-hr LC50 values of LAS were 0.07, 1.03, and 4.36 ppm for M2, PL12, and postlarva 15th substage of the tiger prawn, respectively. The hepatopancreatic glutathione (GSH) in juvenile tiger prawn was obviously depleted when LAS concentration was over 1.0 ppm. The hepatopancreatic GSH content of tiger prawn exposed to solutions of greater than 1.0 ppm LAS was difficult to raise to normal levels, even after the tiger prawns were switched to an LAS-free solution. The activity of malate dehydrogenase in the serum of juvenile tiger prawns exposed to 10.0 ppm LAS solution was significantly increased.

Postoperative hysterosalpingography. Radiographic appearances and clinical results following tubal surgery

Medical records and postoperative hysterosalpingograms on 23 women following tubal surgery who failed to become pregnant within 2-28 months were reviewed. A total of 39 tubes were analyzed. The surgical indications were reversal of tubal ligation in 24 tubes and correction of tubal or perifimbrial disease in 15 tubes. Tubal ligation had been performed by a variety of methods. At surgery, tubal patency, as shown by chromotubation, was seen in 37 (95%) of 39 tubes. On postoperative hysterosalpingography, tubal spillage was present in 32 (82%) of 39 tubes. Radiographically, the tubes that spilled appeared normal except for occasional shortening after reversal of tubal ligation. The eventual pregnancy rate was 8 (35%) of 23 patients, with 7 intrauterine. Pregnancy occurred only in women under 35 years and was more likely in the group having reversal of tubal ligation. We conclude that among patients who do not initially become pregnant following tubal surgery for infertility, tubal patency is restored in most. During hysterosalpingography, tubes operated on may appear normal or shortened. On long-term follow-up, younger patients and those requiring tubal anastomosis only had a higher pregnancy rate.

Mutational study of Streptomyces tyrosinase trans-activator MelC1. MelC1 is likely a chaperone for apotyrosinase

The melanin operon (melC) of Streptomyces antibioticus contains two genes, melC1 and melC2 (apotyrosinase). Our previous studies indicated that MelC1 forms a transient binary complex with the downstream apotyrosinase MelC2 to facilitate the incorporation of copper ion and the secretion of tyrosinase. In this study, we investigated the role of histidine residues in the function of MelC1 by examining a series of substitution or deletion mutants. Of eight mutants only the substitution of His-117 with Asp in the mutant M-117D rendered the complete abolishment of the intracellular tyrosinase activity in both Streptomyces and Escherichia coli. Replacement of His-102 by Leu in the mutant M-102L also caused a 64-70% reduction of tyrosinase activity in Streptomyces and E. coli. These two mutations also affected the secretion of both MelC1 and MelC2 proteins. In vitro copper activation of the purified MelC1.MelC2 binary complex from these two mutants regained only 20-30% tyrosinase activity of the wild type. Biochemical characterization of the tyrosinases from these two mutants revealed that they were different in several aspects. The intracellular tyrosinase activity in M-117D, but not in M-102L, could be partially reactivated by copper ion or by the cell extract containing MelC1. The copper content and the specific activity of the tyrosinase purified from the culture supernatant from M-117D were only 40% of those in wild type and M-102L. Additionally, fast protein liquid chromatography analysis indicated that in these two mutants the copper activation process was defective, very likely due to the incompetent MelC1.MelC2 binary complex formed: reduced association in M-117D and elevated association in M-102L. Furthermore, the conformation of MelC2 in the binary complex or in the mature enzyme form in wild type could be differentiated by the proteinase K digestion pattern, and so did the conformation of MelC2 found in those of M-102L, but not in M-117D mutant. Taken together, our results demonstrate that MelC1 is indispensable in the incorporation of copper ion into MelC2 apotyrosinase via a transient, competent binary complex formation, during which a conformational transition of MelC2 has occurred. This strongly suggests that MelC1 is a chaperone for the apotyrosinase MelC2.

Compression filming with high-density barium suspensions

A method is described for use of high-density barium suspension (250% wt/vol) during compression filming performed in conjunction with the double-contrast examination of the stomach. The technique employs control of the distribution of barium within the stomach by table tilting and use of the vertebral column to stabilize the posterior wall of the stomach. The technique allows routine demonstration of the area gastricae and gastric erosions on compression films, as well as detection of anterior wall lesions that may be undetected by double-contrast films.

Human immunodeficiency virus type 1 Vpu protein is an oligomeric type I integral membrane protein

The human immunodeficiency virus type 1 Vpu protein is a 16-kDa phosphoprotein which enhances the efficiency of virion production and induces rapid degradation of CD4, the cellular receptor for human immunodeficiency virus. The topology of membrane-inserted Vpu was investigated by using in vitro-synthesized Vpu cotranslationally inserted into canine microsomal membranes. Proteolytic digestion and immunoprecipitation studies revealed that Vpu was a type I integral membrane protein, with the hydrophilic domain projecting from the cytoplasmic membrane face. In addition, several high-molecular-weight proteins containing Vpu were identified by chemical cross-linking. Such complexes also formed when wild-type Vpu and a Tat-Vpu fusion protein were coexpressed. Subsequent analysis by one- and two-dimensional electrophoresis revealed that these high-molecular-weight complexes consisted of homo-oligomers of Vpu. These findings indicate that Vpu is a type I integral membrane protein capable of multimerization.

Infiltrating lymphocytes and accessory cells in nasopharyngeal carcinoma

The infiltrating lymphocytes (LCs) and accessory cells (ACs) including dendritic cells (DCs) and monocytes/macrophages in nasopharyngeal biopsies taken from 4 groups of nasopharyngeal carcinoma (NPC) patients were observed by using an immunostaining technique and the correlation of the results to the clinical manifestations and follow-up data was examined. The findings were as follows. (1) NPCs without lymph node metastasis always had marked infiltrating LCs and DCs as compared with those with lymph node(s) metastasis. (2) Advanced NPCs with lymph node(s) involvement (T1-4N1-3M0) and a rapid development of distant metastasis followed by death within 1 year after radiotherapy always showed fewer infiltrating LCs and DCs as compared with those with lymph node(s) metastasis (T1-4N1-3M0) and having longer than 5-year survival after radiotherapy. The amount of both LCs and ACs, especially DCs, infiltrating in NPC tissues appears to be an indicator of the activity of host immune defence mechanisms against cancer and influences the progression of the neoplasm as well as the prognosis.

Human immunodeficiency virus type 1 Vpu protein induces degradation of CD4 in vitro: the cytoplasmic domain of CD4 contributes to Vpu sensitivity

CD4 is an integral membrane glycoprotein which functions as the human immunodeficiency virus (HIV) receptor for infection of human host cells. We have recently demonstrated that Vpu, an HIV type 1 (HIV-1) encoded integral membrane phosphoprotein, induces rapid degradation of CD4 in the endoplasmic reticulum. In this report, we describe an in vitro model system that allowed us to define important parameters for Vpu-dependent CD4 degradation. The rate of CD4 decay in rabbit reticulocyte lysate was approximately one-third of that observed previously in tissue culture experiments in the presence of Vpu (40 versus 12 min) and required no other HIV-1 encoded proteins. Degradation was contingent on the presence of microsomal membranes in the assay and the coexpression of Vpu and CD4 in the same membrane compartment. By using the in vitro degradation assay, the effects of specific mutations in CD4, including C-terminal truncations and glycosylation mutants, were analyzed. The results of these experiments indicate that Vpu has the capacity to induce degradation of glycosylated as well as nonglycosylated membrane-associated CD4. Truncation of 13 C-terminal amino acids of CD4 did not affect the ability of Vpu to induce its degradation. However, the removal of 32 amino acids from the C-terminus of CD4 completely abolished sensitivity to Vpu. This suggests that Vpu targets specific sequences in the cytoplasmic domain of CD4 to induce its degradation. We also analyzed the effects of mutations in Vpu on its biological activity in the in vitro CD4 degradation assay. The results of these experiments suggest that sequences critical for this function of Vpu are located in its hydrophilic C-terminal domain.

Measurement of anti-endothelial and anti-cardiolipin autoantibodies and intercellular adhesion molecules-1 in patients with systemic and cutaneous vasculitis

Two types of autoantibodies and intercellular adhesion molecule-1 (ICAM-1) were measured in patients with vasculitis. There were 13 patients with systemic vasculitis, and 12 with cutaneous vasculitis. The measured antibodies included antiendothelial cell antibodies (AECA) and anti-cardiolipin (ACL) antibodies of three isotypes. Results showed that patients with systemic vasculitis had elevated levels of ICAM-1 and IgG isotype ACL antibodies. Higher levels of ICAM-1 and IgG isotype ACL antibody were found in patients with systemic vasculitis than in those with cutaneous vasculitis. Levels of ICAM-1 and IgG isotype ACL antibodies also decreased after disease activity subsided in patients with systemic vasculitis. Measurement of ICAM-1 and autoantibodies may be useful in evaluating the extent of involvement, and for following the disease course.

Achalasia associated with hiatal hernia: prevalence and potential implications

Although hiatal hernia is reported with a 40-50% frequency in the general population, its occurrence and potential implications in achalasia are less well known. We reviewed the medical records and radiographic examinations of 120 patients with achalasia to assess the prevalence of hiatal hernia and its importance in evaluation and management of this motility disorder. Hiatal hernia was present in only 10 (8.3%) patients. Age, sex distribution, prevalence of dysphagia and regurgitation, and lower esophageal sphincter pressure measured manometrically were not significantly different in patients having hiatal hernia compared to those without hernia. Most patients (88%) underwent pneumatic dilatation and five esophageal perforations occurred, but all in patients without hiatal hernia. In conclusion, hiatal hernia is uncommon in patients with achalasia for reasons not known. Age, sex, symptoms, and results of esophageal manometry were not significantly different in those with hiatal hernia. Finally, the presence of hiatal hernia is not a contraindication to treatment of achalasia by pneumatic dilatation.

Successful treatment of Kaposi's sarcoma with interferon-alpha in a patient with acquired immunodeficiency syndrome

Although combined therapy with interferon-alpha and zidovudine may be safely administered to some patients with the acquired immunodeficiency syndrome (AIDS) and Kaposi sarcoma, no ethnic Chinese patient has been successfully treated before in this area. This case report concerns a 47-year-old male with a history of bisexuality who had suffered from oral ulcers for half a year, Human immunodeficiency virus (HIV) serology was positive, and pathology of the oral ulcers disclosed Kaposi sarcoma. Combination therapy with zidovudine and interferon-alpha was initiated. The patient received a low-dose regimen of 5.0 million U interferon-alpha s.c. per day for 8 weeks and 5 million U twice a week for another 8 weeks. The oral ulcers faded away without recurrence. This report also reviews the literatures on treatment of AIDS-related Kaposi sarcoma with interferon.

In vivo uptake of ethanol and release of acetate in rat liver and GI

The concentration gradients of ethanol and acetate across liver and GI were determined in overnight starved rats infused with ethanol at a rate (15 mu mol/min/rat) below and a rate (30 mu mol/min/rat) exceeding the rate of ethanol disposal in the animals. Plasma concentrations of ethanol in the systemic circulation reached steady-state levels of approximately 0.6 mM between 30 and 60 min during low rate of infusion; increased steadily from 3.5 mM at 30 min to 6.4 mM at 2 h during high rate of infusion. GI metabolism was determined by concentration differences in aorta and portal vein; hepatic metabolism by differences in hepatic influx and hepatic veins. Hepatic influx was the sum of the concentrations in aorta and portal vein, each multiplied by their fractional contributions to hepatic blood supply. At low rate of infusion, hepatic extraction of ethanol was nearly complete and could be accounted for entirely by the acetate released from liver. The concentrations of ethanol in aorta were greater but not significantly than that in portal vein. At high rate of infusion, hepatic and GI gradients of ethanol remained constant despite changes in circulating concentrations of ethanol. The concentration gradients of ethanol and acetate across liver, though different in signs, were identical in magnitude. GI gradient indicating uptake of ethanol was statistically significant and was about 30% of hepatic gradient. Enzyme activity of alcohol dehydrogenase in stomach was found to be about 10% of that in liver. Our results thus show that acetate generated during ethanol oxidation is completely released from liver in rats, in either conscious or anesthetized state under submaximal or maximal condition of ethanol disposal, and that GI metabolism of circulating ethanol can be as high as one third of the metabolism in liver.

Monoclonal gammopathies and the related autoimmune manifestations in Taiwan

A total of 50,000 patients were surveyed for the presence of monoclonal immunoglobulins during the past two decades. There were 411 cases of monoclonal gammopathies including 243 cases of plasma cell neoplasms and 168 cases of secondary plasma-cell dyscrasia. Among the 227 cases of multiple myeloma and Waldenström's macroglobulinemia, there were 49.3% IgG class, 22.9% IgA class, 9.7% IgM class and 13.2% light chain type. In addition, there were 1.3% of nonexcretory myeloma including an IgM type. A relatively high frequency (4.8%) of IgD M-proteins was detected but heavy chain disease was not encountered in the present series. Purified M-components from patients with possible autoimmune manifestations were subjected to immunofluorescence studies. Autoimmune activity of M-proteins was found in a patient of Waldenström's macroglobulinemia with peripheral neuropathy, and another patient of cryofibrinogenemia with recurrent purpura and gangrene. In conclusion, a high frequency of IgD myeloma is found in Chinese patients of this area. M-components may have autoimmune activity resulting in unusual clinical manifestations.

Clinical and videofluoroscopic evaluation of swallowing in 41 patients with neurologic disease

Forty-one patients with neurologic disease (ND) were evaluated by clinical and videofluoroscopic examination of the oral cavity and pharynx to assess location and severity of swallowing dysfunction using various bolus consistencies. Four different materials were given to each patient, and included low- and high-viscosity barium suspensions, barium paste, and paste-coated cookie. Thirty-five patients had abnormalities of both oral and pharyngeal function. Four patients had pharyngeal dysfunction only, and two patients were normal. Mild swallowing difficulties occurred in five patients (12%), moderate dysfunction in 29 patients (71%), and severe dysfunction in five patients (12%). Thirty-two patients had pharyngeal stasis, which was symmetric in 30 patients (94%) and asymmetric in two. Site of stasis was not related to the type of neurologic disease. Fifteen patients aspirated, most of them (13 of 15) with the low-viscosity barium suspension. The predominance of aspiration with the low-viscosity liquid emphasizes the importance of clinical and videofluoroscopic evaluation of swallowing in dysphagic patients with ND for appropriate feeding recommendations. Thus, videofluoroscopy complemented the clinical examination and defined the type and severity of swallowing abnormalities and aspiration, when present.

Prevalence of upper gastrointestinal disease in relation to age: radiologic and clinical implications

Reports of 1126 endoscopies were reviewed to determine the age-related prevalence of upper gastrointestinal (UGI) diseases as a guide to radiologists performing UGI examinations. Results indicate that (1) there were positive findings in 78% of all endoscopic examinations, and thus most symptomatic patients can be expected to have at least one UGI abnormality; (2) many patients with UGI symptoms have two or more reportable disease processes; (3) the prevalence of serious or life-threatening disease, such as cancer or large ulcers, rises steadily with age; and (4) after age 60, approximately 60% of symptomatic patients have a serious UGI disease. Based on these findings, radiologists should not hesitate to make the diagnosis of multiple abnormalities and should expect to diagnose at least one abnormality in most symptomatic patients having an UGI study. Also, because of the high prevalence of serious lesions in the elderly, endoscopy should be considered for the initial examination of an elderly patient if poor physical status would render the radiologic examination difficult or unreliable.

Benign colorectal neoplasms undetected by colonoscopy

This retrospective investigation assessed the sensitivity of colonoscopy for the detection of colonic polyps seen previously at barium enema examination. Included in the study were 77 patients with 106 polypoid lesions. Films showing lesions not subsequently seen at colonoscopy were reviewed and only those lesions with a visible point of attachment, exhibiting no movement in response to filling or change in position of the patient, and confidently diagnosed as a polyp by both reviewing radiologists were included among the 106 lesions. Sixteen lesions (15%) seen radiologically were not located colonoscopically, indicating an endoscopic sensitivity of 85%. Contrary to previous reports, most of the lesions missed endoscopically were in the left colon in regions thought to have been traversed by the instrument. The 15% false-negative rate found for colonoscopy is consistent with existing reports on colonoscopic errors and is approximately the same as the false-negative error rate for radiologic detection of colonic polyps.

Gastroesophageal reflux disease: correlation of esophageal pH testing and radiographic findings

In an attempt to ascertain radiologic efficacy in patients with evidence of gastroesophageal reflux disease (GERD) at pH testing, radiographic findings were correlated with pH values obtained with an esophageal monitor worn for a 24-hour period in 112 patients. Fifteen (30%) of 50 patients with abnormal pH test results had esophagitis diagnosed radiographically, compared with six (10%) of 62 with normal pH test results (P < .05). The severity of abnormal pH monitoring results was classified but did not correlate significantly with the prevalence of esophagitis diagnosed radiographically. Hiatal hernia was also more common (80% vs 60%) in patients with abnormal pH test results (40 of 50 patients) than in those with normal results (37 of 62 patients) (P < .05). Pharyngeal, laryngeal, and pulmonary symptoms were common indications for evaluation, and 14 of 27 (52%) patients with hoarseness had an abnormal pH tracing. Only a minority of patients with evidence of GERD as defined by abnormal pH test results had reflux esophagitis diagnosed radiographically.

Status and trend of HIV-1 infection and AIDS in Taiwan, December, 1991

From May 1, 1985 to December 31, 1991, a total of 4,962,707 serum samples from 8 population groups in Taiwan were tested for anti-human immunodeficiency virus type 1 (anti-HIV-1). In total, 256 samples were seropositive; of these individuals, 43 developed acquired immunodeficiency syndrome (AIDS): 29 were homosexuals; 5 were hemophiliacs; 8 were heterosexuals and 1 was of unknown risk. Although the prevalence of HIV-1 infection and AIDS remains low compared with other countries, since 1988 the increase has been rapid. Before 1977 the majority were homosexuals and hemophiliacs; thereafter the risk groups diversified, with a trend away from homosexuals and hemophiliacs towards heterosexuals and intravenous drug abusers (IVDAs). A few patients have caused serious social problems for the public, health care workers and families. Active community efforts are needed to achieve future success in the control of HIV-1 infection and AIDS in Taiwan.