Multiple vertebral compression fractures in a human immunodeficiency virus-positive patient with glucocorticoid-induced Cushing syndrome treated with percutaneous vertebroplasty: a case report

The authors present a rare case of multiple vertebral compression fractures in a young female with iatrogenic glucocorticoid-induced Cushing syndrome and concomitant human immunodeficiency virus (HIV) infection. Both long-term steroid use and HIV infection may lead to osteopenia or even osteoporosis. Multiple vertebral fractures in young patients are very uncommon and should alert the examiner to investigate any underlying cause. Treatment choices include pharmacological agents such as bisphosphonates or parathyroid hormone and even surgical interventions such as percutaneous vertebroplasty.

Predictive factors for early failure of transarterial embolization in blunt hepatic injury patients

AIM

To evaluate the early success of transarterial embolization (TAE) in patients with traumatic liver haemorrhage and to determine independent factors for its failure.

MATERIALS AND METHODS

From January 2009 to December 2012, TAE was performed in 48 patients for traumatic liver haemorrhage. Their medical charts were reviewed for demographic information, pre-TAE vital signs and laboratory data, injury grade, type of contrast medium extravasation (CME) at CT, angiography findings, and early failure. "Early failure" was defined as the need for repeated TAE or a laparotomy for hepatic haemorrhage within 4 days after TAE. Variables were compared between the early success and early failure groups. Variables with univariate significance were also analysed using multivariate logistic regression for predictors of early failure.

RESULTS

Among 48 liver TAE cases, nine (18.8%) were early failures due to liver haemorrhage. Early failure was associated with injury grade (p = 0.039), major liver injury (grades 4 and 5; p = 0.007), multiple CMEs at angiography (p = 0.031), incomplete TAE (p = 0.002), and elevated heart rate (p = 0.026). Incomplete embolization (OR = 8; p = 0.042), and heart rate >110 beats/min (bpm; OR = 8; p = 0.05) were independent factors for early failure of TAE in the group with major liver injuries.

CONCLUSION

Major hepatic injury is an important factor in early failure. Patients with a heart rate >110 bpm and incomplete embolization in the major injury group have an increased rate of early failure. The success rate of proximal TAE was comparable to that of the more time-consuming, superselective, distal TAE.

Risk factors for liver abscess formation in patients with blunt hepatic injury after non-operative management

PURPOSE

To identify risk factors for liver abscess formation in patients with blunt hepatic injury who underwent non-operative management (NOM).

METHODS

From January 2004 to October 2008, retrospective data were collected from a single level I trauma center. Clinical data, hospital course, and outcome were all extracted from patient medical records for further analysis.

RESULTS

A total of 358 patients were enrolled for analysis. There were 13 patients with liver abscess after blunt hepatic injury. Patients with abscess had a significant increase in glutamic oxaloacetic transaminase (GOT, p = 0.006) and glutamic pyruvic transaminase (GPT, p < 0.0001), and a decrease in arterial blood pH (p = 0.023) compared to patients without abscess in the univariate analyses. In addition, high-grade hepatic injury and transarterial embolization (TAE, p < 0.001) were also risk factors for liver abscess formation. Five factors (GOT, GPT, pH level in the arterial blood sample, TAE, and high-grade hepatic injury) were included in the multivariate analysis. TAE, high-grade hepatic injury, and GPT level were statistically significant. The odds ratios of TAE and high-grade hepatic injury were 15.41 and 16.08, respectively. A receiver operating characteristic (ROC) analysis was used for GPT, and it suggested cutoff values of 372.5 U/L. A prediction model based on the ROC analysis had 100 % sensitivity and 86.7 % specificity to predict liver abscess formation in patients with two of the three independent risk factors.

CONCLUSIONS

TAE, high-grade hepatic injury, and a high GPT level are independent risk factors for liver abscess formation.

Suppressed gene expression of adipocyte resistin in an insulin-resistant rat model probably by elevated free fatty acids

Resistin, the peptide specifically secreted from adipocytes, is a hormone antagonistic to insulin action and, thus, may serve as a link between human obesity due to adiposity and insulin resistance associated with type 2 diabetes. To test this hypothesis, we studied the gene expression of resistin in adipocytes isolated from rats fed with a fructose diet which induced insulin resistance. Compared to the control rats (C) on a normal chow diet, the fructose-fed rats (F) developed hyperinsulinemia, glucose intolerance, hypertriglyceridemia and hypertension, a profile reminiscent of the syndrome X of patients with non-insulin-dependent diabetes mellitus (NIDDM). The F rats had significantly elevated plasma free fatty acids (FFA), enlarged epididymal fat pads, and increased adipocyte size compared with the C rats. We examined the glucose transport and the relative quantity of resistin mRNA produced in the adipocytes of these two groups of rats. Compared to the C rats, the F rats had a clearly reduced insulin-stimulated glucose transport. The gene expression of resistin and other adipocyte peptides was measured on the mRNA by semiquantitative RT-PCR; the validity of this technique was established in advance with a rat-fasting and then refeeding experiment. The F rats showed a decreased expression of the resistin gene, whereas gene expression of leptin and angiotensinogen in contrast increased. Free fatty acids were found to suppress the expression of resistin gene in normal rat adipocytes. These results demonstrate that an insulin-resistant instance in the fructose diet rat model exists with the decreased gene expression of resistin.

Genetic polymorphisms of the promoter region of dopamine D2 receptor and dopamine transporter genes and alcoholism among four aboriginal groups and Han Chinese in Taiwan

This study aims to examine the relationship between the functional polymorphism at the promoter region of the dopamine D2 receptor (DRD2) gene (i.e. -141C Ins/Del) and variable number of tandem repeat polymorphism at the 3' untranslated region of the dopamine transporter (DAT) gene (SLC6A3) with alcoholism in a case-control study. The cases (n = 203) were alcohol dependents with withdrawal symptoms, and the controls (n = 213) were sex- and ethnicity-matched individuals who were screened to exclude those with alcohol problems among four aboriginal groups (Atayal, Ami, Bunun, and Paiwan) and Han Chinese in Taiwan. To control for potential confounding factors, we excluded tobacco abusers from control subjects in part of the analysis and compared the distribution of the genetic polymorphisms in alcoholics with severe medical complications versus those with less severe medical complications. There were no differences in allele and genotype frequencies of these two distinct genetic markers between alcoholics and control subjects in these five different ethnic groups. There was no significant linkage disequilibrium between the -141C polymorphism and two other DRD2 polymorphisms (TaqI A and NcoI). The results remained unchanged when cases were limited to alcoholics with more severe medical complications or when tobacco abusers were excluded from control subjects. The results suggest that both the DRD2 promoter region and the DAT gene do not play a significant role in conferring vulnerability to alcoholism.

Extraction of human DNA for PCR from chewed residues of betel quid using a novel "PVP/CTAB" method

Residues of chewed betel quid (BQ) are often found on crime scenes in Taiwan and possibly some of the Southeast Asian countries. Although these residues are important biological evidences relating to the suspects, the forensic analysis of BQ evidence has been hindered by failures in extraction of human DNA for PCR analysis. Therefore, it is a prerequisite for relevant forensic casework to establish a reliable method for extracting DNA from chewed BQ residues. Three conventional methods (salt/chloroform, 5% Chelex-100 resin, and QIAamp) were first tested for extraction of human DNA from 33 mock BQ samples, which had been stored for less than two months, and 50 four-year-old forensic BQ samples. PCR amplifications from the HLA-DQA1&PM and the STR loci were then used to test the quality of the extracted DNA. For the mock samples, three observations were made. First, PCR amplification of DNA extracted by using these conventional methods had low success rate. Second, the addition of extra Taq DNA polymerase could compensate the lost enzyme activities due to putative inhibitors and, thus, increase the yield. Third, using the Centricon-100 column to remove putative inhibitors substantially improved the efficiency of PCR. However, for the four-year-old forensic BQ samples, none of the attempts for PCR were successful. In order to solve the problem in PCR analysis of DNA from old BQ samples, we developed a DNA extraction method based on the use of polyvinyl pyrrolidone (PVP) and cetyltrimethylammonium bromide (CTAB), which bind to two common classes of PCR inhibitors in plants, polyphenols, and polysaccharides, respectively. The result showed that this "PVP/CTAB" method is completely successful for the mock BQ samples, and 92% (46 out of 50) successful for the four-year-old forensic BQ samples. To our best knowledge, this is the first report of a reliable method for the extraction of human DNA for PCR from chewed BQ residues. This method should provide a useful means for forensic identification in countries where betel chewing is common.

The stimulatory effect of vasoactive intestinal peptides on the cortisol production of guinea pig Zona fasciculata cells: an extra-ACTH regulatory model of the adrenocortical function

The effect of vasoactive intestinal peptide (VIP) on cortisol production was studied in a primary culture enriched with guinea pig Zona Fasciculata (ZF) cells. In ZF cells, VIP stimulates cortisol secretion and enhances the steroidogenic action of ACTH. Compared to ACTH on an equal molar basis, the cortisol-stimulatory effect of VIP is at least 10-fold less potent. As VIP exhibits a wide range of biological actions with widespread distribution in the body, the steroidogenic action of VIP on the adrenal glands is not tissue-specific. There are VIP receptors in ZF cells. With the aid of a VIP receptor antagonist, we found that ACTH and VIP mutually bind each other's receptors with an affinity-ranking order of ACTH > VIP receptor antagonist > VIP. VIP stimulates cortisol production most likely through the cyclic AMP (cAMP) signaling pathway. Both ACTH receptors and the VIP receptors bind VIP receptor antagonist more avidly than VIP, but the bindings do not lead to a consequential effect on cAMP production and cortisol secretion. However, the VIP receptor antagonist counteracted ACTH and VIP to lower both cAMP and cortisol production. In addition, ASIF and BNP-32, which are the proven ACTH receptor antagonists, reduced the cortisol-stimulatory effect of ACTH and VIP. These results suggest that besides ACTH, VIP be an important factor in regulating the cortisol secretion from the adrenal cortex at the site of ACTH receptors. In cases with hypercortisolemia being detected concomitantly with normal or low ACTH levels, we may need to investigate the influential role of VIP.

Acute appendicitis during pregnancy: a clinical assessment

BACKGROUND

Acute appendicitis is the most common non-obstetric reason for laparotomy during pregnancy. The purpose of this study was to analyze the characteristics of the clinical presentations and postoperative outcomes of these patients and their fetuses.

METHODS

Patients who underwent appendectomies during pregnancy from July 1991 to June 1997 were retrospectively identified. Their ages, clinical presentations, the severity of the inflammatory change in the appendices, and the postoperative complications of these patients and fetuses were recorded and analyzed. Long-term outcomes were confirmed by telephone contact, when possible.

RESULTS

Forty-five pregnant women who underwent appendectomies for suspected acute appendicitis were retrospectively reviewed. The histopathological inflammatory change in the appendix was proven in 35 patients (78%). Sixty-three percent of the patients were multiparous, and 86% were in the first 2 trimesters. In the clinical settings, pain and tenderness in the right lower abdominal quadrant were the most common symptoms and signs in presentation. Perioperative administration of ritodrine had no obvious advantage in the prevention of fetal loss. Appendectomy was performed beyond 36 hours of onset of symptoms in 28% of the patients, among whom one-half had gangrenous or perforated appendices. Only one fetus was spontaneously lost in 32 patients with diseased appendices (3%), excluding 3 patients choosing artificial abortion. There was no maternal death in our series.

CONCLUSION

The rate of fetal loss due to surgery for acute appendicitis during pregnancy was low. Delay of operation was pertinent to the more-inflammatory changes of the appendix and to the higher maternal complication rate. Early surgical intervention is essential.

Gallbladder torsion: case report and review of the literature

Torsion of the gallbladder is a surgical emergency, occurring mainly in the elderly. Female is predominant to male with ratio 3 to 1. Despite its unknown etiology, the anatomical variations in the attachment of gallbladder which occur on the mobile mesentery to the inferior margin of the liver are usually found. When the gallbladder twists around the cystic duct and artery, torsion takes place with ensuing occlusion of the flow of bile and blood. Preoperative diagnosis is difficult to make; however, patients who receive prompt surgical treatment with cholecystectomy always get excellent outcomes. Mortality rate is low with 3% to 5%. Here, we report on elderly male patient with gallbladder torsion at our hospital and review the existing literature.

Understanding work-related upper extremity disorders: clinical findings in 485 computer users, musicians, and others

Four hundred eighty five patients whose chief complaints were work related pain and other symptoms received a comprehensive upper-body clinical evaluation to determine the extent of their illness. The group had a mean age of 38.5 years. Sixty-three percent of patients were females. Seventy percent were computer users, 28% were musicians, and 2% were others engaged in repetitive work. The time between the onset of symptoms and our initial visit ranged from 2 weeks to over 17 years. A majority sought care within 30 months with the greatest number of them seeking care before 12 months. Fifty nine percent of subjects were still working when seen despite increasing pain and symptoms such as weakness, numbness, tingling, and stiffness. Following a history, a physical assessment utilizing commonly employed clinical tests were performed including evaluation of joint range of motion, hyperlaxity, muscle tenderness, pain, strength, and imbalance. Neurologic tests included Tinel's sign performed in wrist, elbow, tricipital sulcus, and neck and tests for thoracic out syndrome (TOS). Specific tests such as Finkelstein's test for deQuervain's tenosynovitis, Phalen's test for carpal tunnel syndrome and grip strengths were included in the examination protocol. Significant findings included postural misalignment with protracted shoulders (78%), head forward position (71%), neurogenic TOS (70%), cervical radiculopathy (0.03%), evidence of sympathetic dysfunction (20%), and complex regional pain syndrome (RSD) (0.6%). Hyperlaxity of fingers and elbows was found in over 50%, carpal tunnel syndrome in 8%, radial tunnel syndrome in 7%, cubital tunnel in 64%, shoulder impingement in 13%, medial epicondylitis in 60%, lateral epicondylitis in 33%, and peripheral muscle weakness in 70%. We conclude that despite initial presentation distally, work-related upper-extremity disorders are a diffuse neuromuscular illness with significant proximal upper-body findings that affect distal function. While neurogenic TOS remains a controversial diagnosis, the substantial number of patients with positive clinical findings in this study lends weight to the concept that posture related neurogenic TOS is a key factor in the cascading series of physical events that characterize this illness. A comprehensive upper-body examination produces findings that cannot be obtained through laboratory tests and surveys alone and lays the ground work for generating hypotheses about the etiology of work related upper-extremity disorders that can be tested in controlled investigations.

Simultaneous HPLC of twelve monoamines and metabolites shows neuroblastoma cell line releases HVA and HIAA

Neuroblastoma is a solid tumor occurring usually in children less than 5 years old. It has been difficult to distinguish neuroblastoma from other childhood tumors through morphological diagnosis. Urine homovanillic acid (HVA), which is a metabolite of dopamine, has been proposed as a diagnostic index. Although increased levels of a serotonin metabolite, 5-hydroxyindole-3-acetic acid (HIAA), have also been observed in urine samples of the patients, they were largely attributed to dietary amines. By using an HPLC system with electrochemical detection, which can simultaneously assay 12 monoamines and metabolites, we showed that HVA and HIAA are two of the most prominent monoamine metabolites in the medium after a neuroblastoma cell line (IMR-32) was cultured for 3 days. Moreover, we found that the levels of HVA and HIAA in the media are proportional to the cell densities. These results suggest that the levels of HVA and HIAA in tissue culture media, or in urine from patients whose dietary amines are well controlled, may provide a valuable diagnostic index for neuroblastoma.

Factors determining operative mortality of grade V blunt hepatic trauma

BACKGROUND

Despite recent advances in the management of severe hepatic injuries, the operative mortality rate of grade V hepatic injuries still ranges from 67% to 80%. Grade V hepatic injuries involving the retrohepatic cava or main hepatic veins are almost always lethal, especially those from blunt trauma. The purpose of this study is to understand the risk factors determining operative mortality in grade V blunt hepatic trauma, and to try to improve the surgical management of these injuries.

METHODS

A retrospective study was conducted at a medical center that offers services including primary, secondary, and tertiary care. Forty-four patients with grade V blunt hepatic injuries were treated during a 6-year period from January 1, 1991, to December 31, 1996. The operative mortality was compared by a multivariate analysis.

RESULTS

Forty-four patients with grade V blunt hepatic injuries were identified. Seven patients had only parenchymal injuries, and the others had vascular and associated parenchymal injuries. Venorrhaphy was used in 37 patients; 29 were treated using a nonshunting approach, and 8 with an atriocaval shunt. The overall mortality rate was 68% (30 of 44), and liver-related mortality was 50% (22 of 44). Univariate analysis revealed that the significant variables affecting operative mortality were initial systolic blood pressure, initial base deficit, the Glasgow Coma Scale, injury type, number of resected segments, and total intraoperative blood loss. Based on forward stepping logistic regression analysis, patients with an initial base deficit of -6 mmol/L or less (relative risk = 17.3), and a total intraoperative blood loss of 5,000 mL or more (relative risk = 23.5) would, significantly, encounter a worsening prognosis.

CONCLUSIONS

Initial base deficit and total intraoperative blood loss were the significant factors that determined operative mortality after grade V blunt hepatic trauma. We suggest that prompt resuscitation and expeditious and appropriate surgical management, to control operative blood loss, is the only way to reduce operative mortality in patients with grade V blunt hepatic trauma.

Cytokine dysregulation in activated cystic fibrosis (CF) peripheral lymphocytes

Recent studies demonstrate in vivo and in vitro cytokine dysregulation in CF epithelial cells. To see if these abnormalities may be generalized to other cells expressing cystic fibrosis transmembrane conductance regulator (CFTR) but not directly exposed to local inflammation, we studied mRNA transcription, intracellular protein production and extracellular secretion of IL-2, IL-4, IL-5, IL-10 and interferon-gamma (IFN-gamma) from freshly isolated blood mononuclear and CD4+ T cells from CF patients and controls. Cells were activated by phorbol myristate acetate (PMA) and anti-CD3, PMA-ionomycin, or lipopolysaccharide (LPS) and assessed for cytokine mRNA transcription by semiquantitative reverse transcriptase-polymerase chain reaction, intracellular protein production by flow cytometry, and secretion by supernatant ELISA. Cytokine expression was highly stimulus-dependent. CF cells showed higher IL-10 transcription than control cells after maximal activation by LPS (P = 0.01); despite this, cytokine production and secretion were equivalent to controls. CF cells showed lower cellular IL-10 production after PMA-anti-CD3 activation (P = 0.002). CF cells secreted less IFN-gamma than control cells after maximal activation by PMA-anti-CD3 (1836 +/- 273 pg/ml versus 9635 +/- 3437 pg/ml, P = 0.04). IL-2, IL-4 and IL-5 regulation was similar to controls. We conclude that CF mononuclear cells show selective cytokine dysregulation after maximal activation, namely reduced IFN-gamma secretion and increased IL-10 mRNA without increased production or secretion. These findings extend defects described in respiratory epithelial cells to circulating immunoregulatory cells, suggesting a link between CF genotype and cytokine dysregulation.

Anti-arthropod saliva antibodies among residents of a community at high risk for Lyme disease in California

The role of the western black-legged tick (Ixodes pacificus) versus that of other potential arthropod vectors in the epidemiology of Lyme disease was evaluated by determining the prevalence of anti-arthropod saliva antibodies (AASA) among residents (n = 104) of a community at high-risk (CHR). Salivary gland extracts prepared from I. pacificus, the Pacific Coast tick (Dermacentor occidentalis), the western cone-nose bug (Triatoma protracta), and the western tree-hole mosquito (Aedes sierrensis) were used as antigens in an ELISA. Sera from 50 residents of the San Francisco Bay region in northern California and 51 residents of Imperial County in southern California served as comparison groups. The prevalence of AASA ranged from 2% for A. sierrensis to 79% for I. pacificus in study subjects, 0% for D. occidentalis to 36% for I. pacificus among residents of the San Francisco Bay region, and 6% for I. pacificus to 24% for A. sierrensis in residents of Imperial County. The associations between AASA and demographic factors, potential risk factors, probable Lyme disease, and seropositivity for Borrelia burgdorferi were assessed for 85 members of the CHR. Seropositivity for I. pacificus and B. burgdorferi were significantly correlated, the relative risk of seropositivity to B. burgdorferi was about 5 (31% versus 6%) for subjects who were seroreactive to I. pacificus, nearly every individual who was seropositive for B. burgdorferi had elevated levels of antibodies to I. pacificus, and the mean titer for antibodies to I. pacificus was significantly higher for subjects seropositive versus those seronegative for B. burgdorferi. Together, these findings support the widely held belief that I. pacificus is the primary vector of B. burgdorferi for humans in northern California, and they demonstrate the utility of the AASA method as an epidemiologic tool for studying emerging tick-borne infections.

Three studies testing the effects of role models on product users' safety behavior

Three studies were conducted to determine the effect of a role model's safety behavior on observers' safety behavior. In Studies 1 and 2, role models (confederates) used a cleaning product requiring them to wear safety gloves. Study 1 examined observers' safety behavior after they witnessed a friendly (unfriendly) role model's safety behavior in one of four conditions: 1) wearing rubber gloves, 2) not wearing rubber gloves and experiencing no chemical burn, 3) not wearing rubber gloves and experiencing a mild chemical burn, and 4) not wearing rubber gloves and experiencing a severe chemical burn. In Study 2, participants tested a cleaning product with a warning message (low hazard vs. high hazard) after observing a role model first test the cleaning product in one of the four conditions specified above. As predicted, in Studies 1 and 2, observers were influenced by the role model's safety behavior. However, the friendliness of the role model (Study 1) and level of hazard (Study 2) communicated in the warning message did not influence participants' safety behavior. Using an over-the-counter pain reliever, Study 3 tested the joint effects of: 1) the level of hazard communicated in the warning, 2) observers' outcome-relevant involvement, and 3) role model's compliance. Although the level of hazard communicated in the warning exerted no impact on observers' safety compliance, the role model's safety behavior and level of involvement jointly influenced observers' safety behavior. The implications of the findings and future research directions are discussed. Actual or potential applications of the research include, but are not limited to, using role models in warning messages and safety training programs to demonstrate the proper use of safety gear so as to enhance product users' compliance with safety recommendations.

Evidence that endothelin-1 (ET-1) inhibits insulin-stimulated glucose uptake in rat adipocytes mainly through ETA receptors

The specificity of endothelin (ET) receptors involved in the inhibition of insulin-stimulated glucose uptake (ISGU) in rat adipocytes was investigated. Adipocytes were isolated from the epididymal fat pads of Sprague-Dawley rats. To determine receptor subtypes, we used three ET isopeptides, ET-1 and ET-2, both of which are nonselective agonists, and ET-3, a selective agonist for ETC receptors, to displace [125I]ET-1 binding from the fat cells. The efficiency of displacement was ET-1 > ET-2 >> ET-3, indicating that the primary receptors involved belonged to the ETA subtype. At an equal concentration of 1 micromol/L, BQ-610, a selective ETA antagonist, displaced [125I]ET-1 from binding to fat cells, whereas IRL-1038, a selective ETB antagonist, did not. Using [3H]2-deoxy-D-1-glucose ([3H]2-DG) as a tracer in studies of glucose uptake, we found that equimolar BQ-610 completely reversed the inhibitory effect of ET-1 on ISGU, whereas IRL-1038 was ineffective. Northern blot analysis of adipocyte receptors showed abundant mRNA for ETA, but no ETB subtype. These results clearly demonstrate that ETA is the predominant receptor in rat adipocytes.

Overexpression of vascular endothelin-1 and endothelin-A receptors in a fructose-induced hypertensive rat model

OBJECTIVE

To examine the temporal relationship between hyperinsulinemia and hypertension in the fructose-hypertensive rat model and to study the function of endothelin-1 (ET-1) in fructose-induced hypertension.

DESIGN

Since ET-1 induces insulin resistance in conscious rats, we tested the hypothesis that both hyperinsulinemia and hypertension developed in the fructose-hypertensive rat model might be the sequelae of an elevated tissue content of ET-1 and ET(A) receptors.

MATERIALS AND METHODS

Systolic hypertension was induced within 3 weeks in male Sprague-Dawley rats fed on a fructose-rich diet. After continual monitoring of blood pressure and plasma insulin concentrations, the animals were killed at the end of experiment to determine plasma levels of ET-1, the contractile response of aortic rings to ET-1, and ET-1 and ET(A) receptor gene expressions. In a separate experiment, BQ-610 was administered to lower the effect of ET-1 in rats with fructose-induced hypertension.

RESULTS

Compared with control rats given normal chow, the fructose-fed rats developed systolic hypertension after 3 weeks of the diet (127+/-3.7 versus 110+/-5.5 mmHg, P < 0.01) and hyperinsulinemia both before (1 07.1+/-32.5 versus 48.5+/-14.3 pmol/l, P < 0.005) and after (96.6+/-63.7 versus 50.4+/-5.6 pmol/l, P< 0.05) they became hypertensive. Although plasma ET-1 levels did not differ between the rat groups, aortic ring contraction-concentration curves, indicating vessel contractility in response to ET-1, were significantly greater in these rats than in controls (F1,72 = 12.34, P< 0.00077). Messenger RNA extracted from the tail arteries and blotted with both ET-1 and ET(A) probes showed that fructose-fed rats had greater ET-1 and ET(A)-receptor gene expression than control rats. Concomitant administration of BQ-610 to rats fed on a fructose diet significantly reduced the hypertension. Conclusions These findings suggest that elevated vascular expression of ET-1 and ET(A) receptor genes may mediate the development of hypertension and hyperinsulinemia in rats fed a fructose-rich diet

Protein kinase profile of sperm and eggs: cloning and characterization of two novel testis-specific protein kinases (AIE1, AIE2) related to yeast and fly chromosome segregation regulators

We have analyzed the general protein kinase expression profile in mouse sperm and eggs. A total of 41 different kinases were identified. In this study, we describe two novel protein kinases, designated AIE1 (mouse) and AIE2 (human), which share high amino acid identities with the serine/threonine (S/T) kinase domain of yeast Ip11, fly aurora, and frog Eg2. Mutations in Ip11 and aurora have been reported to cause abnormal chromosome segregation and centrosome separation. Both AIE1 and AIE2 contain a typical S/T kinase domain (251 aa) flanked by a short polypeptide at both ends. Two other AIE-related kinases (STK-1 and IAK1/Ayk1) were also identified in mature mouse oocytes. The central kinase domain of AIE1 revealed 77.6% and 66.3% identity with that of STK-1 and IAK1/Ayk1, but much less homology was found in the sequence outside the kinase domain. Northern blot analysis revealed that both AIE1 and AIE2 are specifically expressed in testis, whereas STK-1 and IAK1/Ayk1 are expressed in many tissues rich in proliferating cells. An in vitro kinase assay showed that AIE1 can phosphorylate casein, AIE1 itself, and an uncharacterized cellular protein (p16). The kinase activity of AIE1 can be destroyed by heat inactivation. In summary, we suggest that AIE is a new member of the S/T kinase family, which may be regulated in a fashion distinct from other AIE-related kinases.

Traumatic thoracic aortic injury caused by a sharp edge of left fractured rib on body position change: case report

Aortic injury caused by penetration of a fractured rib is very rare. We present a patient with aortic injury demonstrated using serial imaging studies. A 66-year-old woman fell from a ladder and sustained multiple left-side rib fractures. There was a small left hemothorax and widened mediastinum on the initial chest roentgenogram in the emergency department. Chest computed tomography (CT) revealed a posterior segmental fracture of the sixth rib on the left side with a sharp edge penetrating into the posterior aspect of the thoracic aorta. It was initially missed. More than 1000 cc of fresh blood suddenly gushed out of the chest tube 7 hours after the traumatic event. After resuscitation, an aortogram was performed which showed blood extravasation from the thoracic aorta at the rib fracture site. Unfortunately, surgical intervention was delayed and she died. Early detection and early surgical intervention are necessary in patients with a widened mediastinum and positive results on imaging studies.

Search for mutations near the alternatively spliced 8-amino-acid exon in the GABAA receptor gamma 2 subunit gene and lack of allelic association with alcoholism among four aboriginal groups and Han Chinese in Taiwan

The alternatively spliced 8-amino-acid exon for the GABAA receptor gamma2 subunit gene (GABRC2) has been postulated to mediate behavioral actions of alcohol. A rapid search for splice-junction mutations near the 8-amino-acid exon using restriction enzymes which normally recognize sequences near or in the exon gave negative results among 217 alcoholics in four aboriginal groups (Ami, Atayal, Bunun and Paiwan) and Han Chinese in Taiwan. The role of the GABRC2 gene in alcoholism was further assessed by a comparison of allelic frequencies revealed by a NciI RFLP between case and control groups. No significant association of alcohol dependence with GABRC2 alleles was observed. These results suggest that the GABRC2 gene probably does not play an essential role in predisposition to alcoholism in the sample population.

Polymorphisms and intron sequences flanking the alternatively spliced 8-amino-acid exon of gamma2 subunit gene for GABAA receptors

Gamma-amminobutyric acid (GABA) is a major inhibitory neurotransmitter. Two alternatively spliced forms of the gamma2 subunit of GABAA receptor (gamma2L and gamma2S), which differ by an exon of eight amino acids, show different sensitivities to modulatory effects of ethanol on receptor activities. A 2.7 kb DNA fragment and an 1.7 kb DNA fragment covering respectively the introns upstream and downstream from the 8-amino-acid exon were obtained through PCR-amplification of human genomic DNA using primers derived from cDNA sequences. Total sequencing of these fragments showed a composite 4.2 kb segment containing the 8-amino-acid exon and consensus sequences for RNA splice junctions. Restriction fragment length polymorphisms (RFLP) based on NciI restriction digestion were found among Chinese in Taiwan. This RFLP provides a useful DNA marker for allelic association or linkage analyses of the role of GABAA receptors in predisposition to alcoholism or other neuropsychiatric disorders.

Dopamine D2 receptor gene and alcoholism among four aboriginal groups and Han in Taiwan

Previous studies examining the putative association between DRD2 TaqI A1 and alcoholism have produced conflicting results. Major critiques of such studies include potential confounding arising from population admixture by inappropriate selection of controls, failure to screen out substance abusers from controls, and the failure to assess the severity of alcoholics. To address these issues, we compared the allelic frequency of two polymorphisms of DRD2, TaqI A and NcoI, among severe alcoholics and their ethnically matched nonalcoholic controls within four major aboriginal groups and Han (Chinese) in Taiwan. The sample of alcoholics and controls examined for the five groups included 36 and 31 (Atayal), 24 and 23 (Ami), 58 and 58 (Bunun), 35 and 35 (Paiwan), and 50 and 66 (Han). A borderline association between TaqI A1 and alcoholism among the Ami (P = 0.08) and an association between NcoI N1 and alcoholism among Han (P = 0.01) were found. Results of haplotype analysis further confirm that the frequency of haplotype A1N1 was higher in alcoholics than in controls for the Ami (P = 0.01) and Han (P = 0.03). If controls with tobacco abuse were excluded from the analysis, the results remained unchanged. Severity in medical complications of alcohol dependence with withdrawal symptoms was not associated with higher prevalence of DRD2 TaqI A1 or NcoI N1 alleles. The absence of an association between DRD2 and alcoholism among the three aboriginal groups suggests either a higher rate of phenocopies among aboriginal alcoholics or genetic heterogeneity in the susceptibility to alcoholism.

Alcohol dehydrogenase and aldehyde dehydrogenase genotypes and alcoholism among Taiwanese aborigines

Previous population association studies have indicated that certain alleles of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) genes may reduce the risk of alcoholism in Oriental populations. In this report we determined the genotypes for three genes, ADH2, ADH3, and ALDH2 among subjects with alcohol dependence (n = 159) and ethnically matched normal controls (n = 149) for the four largest aboriginal groups (Atayal, Ami, Bunun, and Paiwan) in Taiwan. The ethnicity matching used in this study was feasible because there are still few intergroup marriages between these aboriginal groups. On a group level, the rare frequencies of ALDH2*2, the inactive allele of ALDH2, among these aborigines may account partially for their vulnerability to alcohol use disorders. On an individual level, however, the genotypes controlling alcohol metabolism did not account for intragroup differences in vulnerability to alcoholism except in the case of ADH2 for the Ami ethnic group.

Septic arthritis of adult hip treated by total hip replacement--a case report

Septic arthritis is usually seen in children as an acute febrile illness induced by septicemia, local inoculation of a joint caused by trauma or adjacent osteomyelitis. It also occurs in adults particulary those with debilitating disease or sepsis at other sites. It normally happens in knee joints, but rarely in hip joints. A 65-year-old patient suffered from hip pain and febrile episodes intermittently for two months. Diagnostic hip aspiration was performed with 60 ml pus drained. The aspirate grew Staphylococcus aureus. Hip arthrotomy was performed with extensive debridement. Eighteen months later, this patient received total hip replacement and he has remained well for 8 years, with no evidence of infection or of implants loosening.

Reduced IL-10 secretion by CD4+ T lymphocytes expressing mutant cystic fibrosis transmembrane conductance regulator (CFTR)

Expression of the CFTR protein is thought to be physiologically important only in exocrine epithelial cells. However, chronic respiratory inflammation and infection remain unexplained phenomena in disease pathogenesis. Non-transformed, antigen-responsive CD4+ T cells cloned from healthy controls and CF patients homozygous or heterozygous for the delta F508 mutation transcribed CFTR mRNA and expressed immunoreactive cytoplasmic CFTR protein. T cell clones (TCC) from controls and CF patients displayed equivalent Ca(2+)-mediated Cl- current; however, TCC from patients with CF but not controls displayed defective cAMP-mediated Cl-current. Although CF-derived TCC preserved mitogen and antigen proliferative responses and specificity to tetanus toxoid epitopes, they selectively secreted approximately 45% less IL-10 compared with control TCC after activation with concanavalin A (Con A) (624 +/- 101 versus 1564 +/- 401 pg/ml per 10(6) cells, respectively; P = 0.04) or anti-CD3/phorbol ester (5148 +/- 1634 versus 11788 +/- 2390 pg/ml; P = 0.05). This difference was independent of atopy. Secretion of interferon-gamma, IL-2, and IL-4 was comparable in CF and control TCC after both forms of activation, while IL-5 was reduced in CF TCC following anti-CD3/phorbol myristate acetate (PMA) but not after Con A. We conclude that expression of mutant CFTR in human TCC is accompanied by ion channel dysfunction characteristic of the CF phenotype, and is accompanied by a reduction in IL-10 secretion after polyclonal activation. It is possible that disruption of IL-10-mediated anti-inflammatory homeostasis may contribute to early onset sustained inflammation in CF airways.

Endothelin-1 induces insulin resistance in conscious rats

Since endothelin-1 (ET-1) might regulate insulin secretion and glucose metabolism, we carried out experiments to study the effect of ET-1 in conscious rats by injecting ET-1 (0.5 or 1.0 microgram/100 g body weight, i.p.) and examining the plasma glucose (PG) and insulin (PI) concentrations and PG/PI ratios continuously for 3 hours after the injection. Compared to the saline controls, ET-1 increased PG and PG/ P1 ratios in a dose-dependent manner. Oral glucose tolerance test (OGTT) performed at 30 min after the injection showed that PG levels stayed significantly higher in rats preinjected with ET-1 than rats with saline injection, although the change in PI levels was not different. Simultaneous infusion of glucose and insulin to somatostatin-primed rats with ET-1 or saline injection resulted in significantly higher steady state plasma glucose (SSPG) levels and SSPG/PI ratios in rats injected with ET-1 than control rats with saline. These results unequivocally indicated that intraperitoneally administered ET-1 induces insulin resistance in conscious rats.

Association of monoamine oxidase A alleles with alcoholism among male Chinese in Taiwan

OBJECTIVE

The role of monoamine oxidase (MAO) in alcoholism was assessed by genetic association studies separately in five ethnic groups in Taiwan.

METHOD

Restriction fragment length polymorphisms (RFLP) and dinucleotide repeat polymorphisms (DNRP) were used to determine MAOA and MAOB alleles in male alcoholic patients and nonalcoholic comparison subjects among Han Chinese and four aboriginal groups.

RESULTS

Significant associations of alcohol dependence with MAOA alleles (RFLP and DNRP) were found among the Han Chinese, but not among the aboriginal groups. No significant association with MAOB DNRP alleles was found in any group.

CONCLUSIONS

Genetic heterogeneity may underlie alcoholism among different ethnic groups in Taiwan, and MAOA mutations may play a role in susceptibility to alcoholism among Han Chinese.

Alcohol-metabolising genes and alcoholism among Taiwanese Han men: independent effect of ADH2, ADH3 and ALDH2

BACKGROUND

Previous population association studies have indicated that certain alleles of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) may reduce the risk of alcoholism in Asian populations. The association of ALDH2 and ADH2 with the development of alcoholism was found to be independent of each other and has been replicated in different Asian populations, while the effect of ADH3 is less studied.

METHOD

We genotyped the alcohol metabolism genes among Han men with alcohol dependence (n = 46) and their ethnically matched normal controls (n = 63) in Taiwan. Multiple logistic regression was then applied to assess the contribution of ADH3 to alcoholism by controlling the effect of ALDH2 and ADH2.

RESULTS

The results of multivariate analyses demonstrated that the odds ratios for an increment of one allele of ADH2*1, ADH3*2 and ALDH2*1 in the development of alcoholism were 4.18, 3.82, and 6.89, respectively.

CONCLUSIONS

These findings clearly indicate that all three alcohol-metabolising genes contribute to susceptibility to alcoholism.

Mutational analysis of the human MAOA gene

The monoamine oxidases (MAO-A and MAO-B) are the enzymes primarily responsible for the degradation of amine neurotransmitters, such as dopamine, norepinephrine, and serotonin. Wide variations in activity of these isozymes have been reported in control humans. The MAOA and MAOB genes are located next to each other in the p11.3-11.4 region of the human X chromosome. Our recent documentation of an MAO-A-deficiency state, apparently associated with impulsive aggressive behavior in males, has focused attention of genetic variations in the MAOA gene. In the present study variations in the coding sequence of the MAOA gene were evaluated by RT-PCR, SSCP, and sequencing a mRNA or genomic DNA in 40 control males with > 100-fold variations of MAO-A activity, as measured in cultured skin fibroblasts. Remarkable conservation of the coding sequence was found with only 5 polymorphisms observed. All but one of these were in the third codon position and thus did not alter the deduced amino acid sequence. The one amino acid alteration observed, lys --> arg, was neutral and should not affect the structure of the protein. This study demonstrates high conservation of coding sequence in the human MAOA gene in control males, and provides primer sets which can be used to search genomic DNA for mutations in this gene in males with neuropsychiatric conditions.

Activation of CFTR chloride current by nitric oxide in human T lymphocytes

Nitric oxide, which is produced by cytokine-activated mononuclear cells, is thought to play an important role in inflammation and immunity. While the function of nitric oxide as a direct cytotoxic effector molecule is well established, its function as a transducer molecule in immune cells is not. By use of whole-cell patch clamp recordings, we show that nitric oxide activates cystic fibrosis transmembrane conductance regulator CI- currents in normal human cloned T cells by a cGMP-dependent mechanism. This pathway is defective in cystic fibrosis-derived human cloned T cells. These findings not only delineate a novel transduction mechanism for nitric oxide but also support the hypothesis that an intrinsic immune defect may exist in cystic fibrosis.

Organization of the human monoamine oxidase genes and long-range physical mapping around them

A 265-kb yeast artificial chromosome containing sequences for human monoamine oxidase A and B (MAO-A and MAO-B) genes has been characterized. These two genes are localized within a region of about 240 kb and are arranged in a tail-to-tail configuration, with the 3' coding sequences separated by about 50 kb. A region about 2.5 Mb around the MAO loci was mapped by pulsed-field gel electrophoresis (PFGE). Comparisons between the restriction maps derived from the YAC and the long-range map derived from genomic digestions were in general agreement. The important features identified include a CpG island at the 5' end of the MAO-A and MAO-B genes, respectively. The combined information supports the order of markers within this region to be DXS77-DXS7-MAOA-MAOB.

RFLP for human DBH (dopamine beta-hydroxylase)

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Biochemistry and genetics of monoamine oxidase

This chapter reviews the two mitochondrial flavin containing isozymes of monoamine oxidase. Section 1, "Biochemistry" discusses assays, substrates and inhibitors, phylogenic and tissue distribution, interactions with lipids, nutritional studies, protein structure, kinetic and chemical mechanistic proposals, and biosynthesis. Section 2, "Inheritance" discusses possible genes involved in expression, genetic studies of platelet MAO-B and fibroblast MAO-A, and chromosomal location. Section 3, "Molecular Genetics" reviews the cloning of their cDNAs, their intra- and interspecies homology and structural inferences made from deduced amino acid sequences. Section 4, "Regulation" gives an overview of levels in development and aging, and effect of drugs. The final section 5, "Role in Human Disease" discusses physiological function and effects of altered levels in humans and animal models including complete absence due to a submicroscopic chromosomal deletion in several human patients.

Pseudomonas hyperimmune globulin passive immunotherapy for pulmonary exacerbations in cystic fibrosis

We studied the effect of an intravenously administered gamma globulin [Ps-ivIG] enriched fivefold over conventional ivIG for Pseudomonas aeruginosa lipopolysaccharide [PA LPS] antibodies on ten patients with cystic fibrosis [CF] aged 19-32 years during hospitalization for pulmonary deterioration. All were colonized with greater than or equal to 1 PA phenotype resistant to all antibiotics at the time of admission and they received 500 mg/kg Ps-ivIG intravenously as a single dose in addition to conventional treatment, including antibiotics and chest physiotherapy. No adverse effects occurred. Circulating immune complexes and complement levels remained unchanged from baseline. Serum levels of anti-PA LPS IgG, as measured by ELISA for eight PA LPS immunotypes, increased to 244 +/- 65% (mean +/- SE) of baseline levels 1 hour post-infusion (P less than 0.01), remained significantly elevated during a mean hospital stay of 17 days, and returned to near baseline by follow-up 4 weeks after hospital discharge. Plasma half-life and clearance values were similar to those of other subjects receiving conventional ivIG. Sputum PA density declined from 3.0 to 1.2 x 10(8) cfu/mL 1 week post-infusion (P approximately equal to 0.05), and returned to baseline at follow-up. Serum anti-PA opsonic activity increased after infusion (P less than 0.01), but returned to baseline by 72 hours. Clinical scores improved from admission to discharge (P less than 0.005) without decline at follow-up. Forced vital capacity [FVC] and forced expiratory volume in one second [FEV1] increased from admission to discharge (P less than 0.01 and P less than 0.05, respectively) without decline at follow-up. Using autologous historical control data, standard hospital therapy without Ps-ivIG resulted in no improvement in FVC or FEV1, and a subsequent decline in these parameters (P less than 0.05 for each) during a similar follow-up period. This occurred despite the fact that half the patients did not have antibiotic-resistant PA on the control admission. We conclude that Ps-ivIG is a safe adjunctive therapy for pulmonary exacerbations in moderately ill cystic fibrosis patients colonized with resistant PA, and may be associated with both greater and more prolonged improvement in pulmonary function than standard therapy alone.

Nonopsonic antibodies in cystic fibrosis. Pseudomonas aeruginosa lipopolysaccharide-specific immunoglobulin G antibodies from infected patient sera inhibit neutrophil oxidative responses

Antibody opsonins from cystic fibrosis (CF) patients were investigated using nonmucoid and mucoid lipopolysaccharide (LPS) immunotype 1 Pseudomonas aeruginosa as bacterial ligands and PMN phagocytes. CF sera were compared to normal sera, polyvalent PA LPS hyperimmune globulin, and isotype switch variant monoclonal antibodies (MAbs) specific for type 1 PA LPS. Sera from PA-infected CF patients (CF PA+) had elevated levels of PA LPS and alginate IgG antibodies and promoted significantly greater antibody-dependent PMN chemiluminescence responses than sera from uninfected CF patients (CF PA-) or normal human sera (NHS). After adjustment for autologous IgG PA LPS antibody content, however, CF PA+ sera had less antibody-dependent opsonic activity than sera from CF PA- patients (P less than 0.025) or NHS (P less than 0.0025), suggesting qualitative opsonic defects of IgG PA LPS antibodies in CF PA+ sera. Antigen-specific immunoprecipitation of PA LPS antibodies enhanced opsonization by 40% of CF PA+ sera while uniformly reducing that from CF PA- sera (P less than 0.01), indicating LPS-specific nonopsonic antibodies in some CF PA+ sera. Alginate antibodies were not critical opsonins in most uninfected CF patient sera. PA LPS IgG antibodies isolated by immunoaffinity chromatography from NHS, hyperimmune globulin, and CF PA- sources were opsonic and had greater activity at equal antigen-binding concentration than identical antibodies isolated from infected CF patients (P less than 0.01-0.05); the majority of isolates from CF PA+ sera did not promote PMN oxidative responses above nonopsonic baseline. A potential isotypic basis for these findings was supported by differences in PMN responses to PA opsonized with MAbs of identical specificity but differing isotypes. PA LPS-specific IgG antibodies inhibiting PMN oxidative responses in infected patient sera demonstrate antigen-specific immunomodulation of host responses by chronic bacterial parasitism in CF, which may play a role in the pathophysiology of lung disease.

Localization of human monoamine oxidase-A gene to Xp11.23-11.4 by in situ hybridization: implications for Norrie disease

A cDNA for the neurotransmitter-degrading enzyme monoamine oxidase-A (MAO-A) has been assigned by in situ hybridization to the human X chromosome and subregionally localized to Xp11.23-11.4. As restriction fragments detected by this probe are deleted in some patients with Norrie disease, this assignment provides confirmation of the localization of the disease.

The primary structure of bovine monoamine oxidase type A. Comparison with peptide sequences of bovine monoamine oxidase type B and other flavoenzymes

We have isolated cDNA clones believed to encompass the full-length coding sequences for a subunit of bovine monoamine oxidase type A (MAO-A). The clones code for an apoprotein of 527 amino acid residues corresponding to a molecular mass of 59,806 Da. The inferred protein sequences show an overall similarity of 68% with partial amino acid sequences of bovine type B MAO (about 41% of the total sequence), as well as a greater similarity (greater than 90%) with some regions including that for the published sequence of the flavin-binding region. Sequence comparisons indicate that these two forms of MAO are encoded by distinct genes. Comparison of this sequence with other flavoenzymes showed similarity with regions associated with non-covalent flavin-binding sites. Analysis of mRNAs coding for MAO enzymes showed a heterogeneity of transcripts consistent with several different forms of monoamine oxidase.

Monoamine oxidase deficiency in males with an X chromosome deletion

Mapping of the human MAOA gene to chromosomal region Xp21-p11 prompted our study of two affected males in a family previously reported to have Norrie disease resulting from a submicroscopic deletion in this chromosomal region. In this investigation we demonstrate in these cousins deletion of the MAOA gene, undetectable levels of MAO-A and MAO-B activities in their fibroblasts and platelets, respectively, loss of mRNA for MAO-A in fibroblasts, and substantial alterations in urinary catecholamine metabolites. The present study documents that a marked deficiency of MAO activity is compatible with life and that genes for MAO-A and MAO-B are near each other in this Xp chromosomal region. Some of the clinical features of these MAO deletion patients may help to identify X-linked MAO deficiency diseases in humans.

Structural features of human monoamine oxidase A elucidated from cDNA and peptide sequences

Monoamine oxidase (MAO), an important enzyme for the degradation of amine neurotransmitters, has been implicated in neuropsychiatric illness. The amino acid sequence for one form of the enzyme, MAO-A, has been deduced from human cDNA clones and verified against proteolytic peptides. The covalent binding site for the flavin adenine dinucleotide (FAD) cofactor is near the C-terminal region. The presence of features characteristic of the ADP-binding fold suggests that the N-terminal region is also involved in the binding of FAD. These cDNAs should facilitate the study of the structure, function, and intracellular targeting of MAO, as well as the analysis of its expression in normal and pathological states.

Human monoamine oxidase gene (MAOA): chromosome position (Xp21-p11) and DNA polymorphism

An essentially full-length cDNA clone for the human enzyme monoamine oxidase type A (MAO-A) has been used to determine the chromosomal location of a gene encoding it. This enzyme is important in the degradative metabolism of biogenic amines throughout the body and is located in the outer mitochondrial membrane of many cell types. Southern blot analysis of PstI-digested human DNA revealed multiple fragments that hybridized to this probe. Using rodent-human somatic cell hybrids containing all or part of the human X chromosome, we have mapped these fragments to the region Xp21-p11. A restriction fragment length polymorphism (RFLP) for this MAOA gene was identified and used to evaluate linkage distances between this locus and several other loci on Xp. The MAOA locus lies between DXS14 and OTC, about 29 cM from the former.

Altered antibody isotype in cystic fibrosis: impaired natural antibody response to polysaccharide antigens

Patients with cystic fibrosis (CF) have impaired natural (preinfection) IgG2 antibody responses to Pseudomonas aeruginosa lipopolysaccharide. To investigate the basis for this defect, we measured natural IgG and IgG1-4 antibody levels to Haemophilus influenzae type b polyribophosphate (PRP) and tetanus toxoid by enzyme-linked immunosorbent assay in 24 adult CF patients and 20 normal controls. Immunoglobulin heavy- and light-chain allotypes were determined on 146 Caucasian CF patients and 96 controls. The tetanus toxoid-specific IgG response was predominantly IgG1. CF and control subjects had similar IgG and IgG1 antibody levels. The PRP-specific IgG response was predominantly IgG2. In contrast to tetanus toxoid results, CF patients had lower geometric mean level of PRP-specific IgG compared to normal controls (p = 0.0036). ELISA results were confirmed by liquid-phase 3H-PRP-binding assay: CF patients had a geometric mean serum antibody level of 395 versus 922 ng/ml in controls (p = 0.0044). PRP-specific IgG2 levels were also depressed in CF patients (p = 0.03). CF patients had a lower prevalence of the A2m(2) allotype than the local racially matched control sample (p less than 0.025). Other allotype prevalences including G2m(n) and Km(1) were similar. Impaired IgG2 antibody responses to microbial polysaccharide surface antigens in CF patients might predispose them to persistent endobronchial infection and lead to production of nonopsonizing isotype responses. The potential role of A2m(2), coded for in the H chain locus on chromosome 14, is unknown, but could be related to mucosal IgA2 antibody responses.

Performance characteristics of immunoenzymatic allergosorbent testing for total and specific immunoglobulin E

Paper disc-based solid phase radioimmunoassays are widely used in vitro diagnostic test kits for measuring total IgE (Phadebas PRIST) and specific IgE antibodies (RAST). Recently, these kits have been modified by the substitution of an enzyme-linked immunosorbent assay detection system (Phadezym PRIST/RAST). We studied the performance characteristics of Phadezym PRIST and RAST kits. Phadezym PRIST was sensitive to 0.5 IU/mL IgE. Reproducibility was excellent in the range of 5 to 200 IU/mL IgE and adequate in the range of 5 to 1000 IU/mL using 1:10 serum dilutions (average inter-assay coefficient of variation = 19%). Phadezym RAST was specific, but sensitivity was limited by absorbances in the RAST class 1/0 range indistinguishable from background values. Average inter-assay coefficient of variation was 29% for the semi-quantitative 'Phadezym RAST Unit' (PRU) reporting system. We modified the test kit procedure by disc incubations in microtiter plate wells with rotational agitation and use of ELISA-dedicated spectrophotometer and computer software. These microplate accelerated computerized assays ('MacPRIST' and 'MacRAST') were shown to perform similarly to the conventional Phadezym procedures with advantages in speed, ease, and handling of data.