276
|
Mounsey JP, Mistry DJ, Ai CW, Reddy S, Moorman JR. Skeletal muscle sodium channel gating in mice deficient in myotonic dystrophy protein kinase. Hum Mol Genet 2000; 9:2313-20. [PMID: 11001935 DOI: 10.1093/oxfordjournals.hmg.a018923] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Myotonic dystrophy, a progressive autosomal dominant disorder, is associated with an expansion of a CTG repeat tract located in the 3'-untranslated region of a serine/threonine protein kinase, DMPK. DMPK modulates skeletal muscle Na channels in vitro, and thus we hypothesized that mice deficient in DMPK would have altered muscle Na channel gating. We measured macroscopic and single channel Na currents from cell-attached patches of skeletal myocytes from mice heterozygous (DMPK(+/-)) and homozygous (DMPK(-/-)) for DMPK loss. In DMPK(-/-) myocytes, Na current amplitude was reduced because of reduced channel number. Single channel recordings revealed Na channel reopenings, similar to the gating abnormality of human myotonic muscular dystrophy (DM), which resulted in a plateau of Na current. The gating abnormality deteriorated with increasing age. In DMPK(+/-) muscle there was reduced Na current amplitude and increased Na channel reopenings identical to those in DMPK(-/-) muscle. Thus, these mouse models of complete and partial DMPK deficiency reproduce the Na channel abnormality of the human disease, providing direct evidence that DMPK deficiency underlies the Na channel abnormality in DM.
Collapse
|
277
|
Shimbo D, Osende J, Reddy S. Excess risk of MI in patients treated with antidepressant medications. Am J Med 2000; 109:68-9. [PMID: 10991739 DOI: 10.1016/s0002-9343(00)00432-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
278
|
Jackson T, Reddy S, Fincham J, Abd-Alla M, Welles S, Ravdin J. A comparison of cross-sectional and longitudinal seroepidemiological assessments of entamoeba-infected populations in South Africa. Arch Med Res 2000; 31:S36-7. [PMID: 11070215 DOI: 10.1016/s0188-4409(00)00150-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
279
|
Kandasamy R, Koh KF, Tham SL, Reddy S. Anaesthesia for caesarean section in a patient with Eisenmenger's syndrome. Singapore Med J 2000; 41:356-8. [PMID: 11026804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Eisenmenger's syndrome was originally described in 1897 and redefined by Wood in 1958. This syndrome includes pulmonary hypertension with reversed or bi-directional shunt associated with septal defects or a patent ductus arteriosus. A 27-year-old G2 PO with Eisenmenger's syndrome presented to the hospital for management at 17 weeks of pregnancy. She was advised termination of pregnancy but she refused. An elective caesarean section was performed successfully under general anaesthesia uneventfully at 29 weeks due to severe intrauterine growth retardation (IUGR). Patient's postoperative complications like pulmonary thromboembolism, the advantages and disadvantages of anticoagulation are discussed. Pregnancy carries substantial maternal and fetal risk for patients with pulmonary hypertension and Eisenmenger's syndrome. Although pregnancy should be discouraged in women with Eisenmenger's syndrome it can be successful.
Collapse
|
280
|
Abd-Alla MD, Jackson TF, Reddy S, Ravdin JI. Diagnosis of invasive amebiasis by enzyme-linked immunosorbent assay of saliva to detect amebic lectin antigen and anti-lectin immunoglobulin G antibodies. J Clin Microbiol 2000; 38:2344-7. [PMID: 10835000 PMCID: PMC86799 DOI: 10.1128/jcm.38.6.2344-2347.2000] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Saliva from subjects with amebic liver abscess (ALA), acute amebic colitis, asymptomatic infection with Entamoeba histolytica or Entamoeba dispar, and uninfected controls was tested by enzyme-linked immunosorbent assay (ELISA) for the presence of E. histolytica galactose-inhibitable lectin antigen and salivary immunoglobulin (IgG) antibodies to a recombinant cysteine-rich lectin-derived protein (LC3). Salivary lectin antigen was found in 65.8% of subjects with acute colitis, compared to 22.2% of those convalescent from ALA, 10.0% with asymptomatic E. histolytica infection, 9.8% with E. dispar infection, and 2.6% of controls (subjects from the United States and study patients with nonamebic diarrhea) (P < 0.001 for each compared to values for subjects with colitis). Salivary anti-LC3 IgG antibodies were found in 92% of ALA patients regardless of duration of illness and in 83.3% of colitis patients who were symptomatic for at least 7 days (P < 0.001 compared to other study groups). Serum anti-LC3 IgG antibodies were detected in 56.3% of subjects with acute colitis, 100% of subjects with ALA or prolonged colitis, 45% of subjects with asymptomatic E. histolytica infection, 32.3% of subjects with E. dispar infection, and 23.4% of diarrhea controls. In comparison to ELISA for serum anti-LC3 IgG antibodies, the salivary lectin antigen assay is a more sensitive and specific test for acute amebic colitis. Detection of salivary anti-LC3 IgG antibodies by ELISA is an effective means for the diagnosis of ALA and prolonged cases of amebic colitis.
Collapse
|
281
|
Clements RH, Reddy S, Holzman MD, Sharp KW, Olsen D, Holcomb GW, Richards WO. Incidence and significance of pneumomediastinum after laparoscopic esophageal surgery. Surg Endosc 2000; 14:553-5. [PMID: 10890964 DOI: 10.1007/s004640000164] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Pneumomediastinum can be a sign of esophageal perforation. During laparoscopic esophageal surgery, the mediastinum is exposed to carbon dioxide gas under pressure that can cause pneumomediastinum. METHODS Forty-five patients undergoing laparoscopic esophageal procedures had erect, inspiratory, single-view chest radiographs (CXR) performed in the recovery room (RR). Patients with extraabdominal gas underwent daily erect, inspiratory, single-view CXR until resorption of the gas or discharge from the hospital. Insufflation time and pressure were recorded, and morbidity was evaluated. Results are expressed as mean +/- SEM. RESULTS Twenty-five men (56%)and 20 women (44%) aged 33.0 +/- 2.9 years underwent 10 Heller myotomies (22.2%), 27 Nissen fundoplications (60.0%), six Toupet fundoplications (13.3%), and two paraesophageal hernia repairs (4.4%). Twenty-four patients (53.3%) had normal CXR in RR, and 21 (46.7%) had extraabdominal gas. Eighteen (85.7%) of the 21 had pneumomediastinum, three (14.3%) had pneumothorax, and 12 (57.1%) had subcutaneous emphysema in RR. Sixteen of these 21 remained hospitalized and had repeat CXR on postoperative day 1. Of these 16, five (31.3%) had normal CXR, 11 (68.8%) had pneumomediastinum, and seven (43.8%) had subcutaneous emphysema. There were no esophageal perforations and no chest tube insertions, and there was no morbidity related to pneumomediastinum. CONCLUSION Pneumomediastinum is observed frequently following laparoscopic esophageal operations and often persists past 24 h. After these operations, pneumomediastinum is not necessarily indicative of esophageal perforation. In this group, it caused no clinically significant events that altered the course of the patients.
Collapse
|
282
|
Birdi I, Chaudhuri N, Lenthall K, Reddy S, Nashef SA. Emergency reinstitution of cardiopulmonary bypass following cardiac surgery: outcome justifies the cost. Eur J Cardiothorac Surg 2000; 17:743-6. [PMID: 10856870 DOI: 10.1016/s1010-7940(00)00453-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE Crash back on bypass (crash-BOB) is occasionally required in the resuscitation of patients developing life-threatening complications following cardiac surgery. This study aims to determine the incidence, aetiology and cost-effectiveness of such intervention. METHODS Retrospective review of all crash-BOB patients over 5.5 years at one hospital. RESULTS The incidence of crash-BOB was 0.8% and occurred at a mean of 7 h post-operatively (range 1 h-20 days). Pre-operative Parsonnet scores were similar to the overall population of patients undergoing surgery in our institution (mean score 10; range 0-45). The original cardiac operations were coronary revascularization (39), valve surgery (12) and others (4). Indications for crash-BOB were cardiac arrest (23), bleeding (20), hypotension (7), ischaemia (1) and others (4). Of the 55 patients, 20 died on the operating table. Of the remaining 35, a further 12 died in hospital. Overall survival was therefore 42%. Where crash-BOB was for bleeding, 17 of 20 patients (85%) survived to leave theatre, of whom 11 patients (55%) left hospital alive. In the 35 non-bleeders, only 18 (51%) survived crash-BOB and 12 (34%) left hospital alive. Sixteen patients required a second period of aortic cross-clamping of whom 13 (81%) survived to leave theatre, and 11 (69%) left hospital alive. Conversely, of nine patients in whom no specific diagnosis was found during crash-BOB, only two (22%) survived the procedure and none survived to hospital discharge. Multiple logistic regression identified pre-operative Parsonnet score (P=0.045) and the need for aortic cross-clamping to deal with an identified surgical problem (P=0.03) as significant predictors of hospital survival. Indication for crash-BOB (bleeder/non-bleeder) failed to reach significance (P=0.08). Age, sex, intra-aortic balloon pump use at the primary procedure, and time following the primary procedure to crash-BOB were not identified as predictors of hospital survival. Of the 23 hospital survivors, three patients suffered a stroke post-operatively and made a good functional recovery prior to discharge. Two patients developed sternal wound dehiscence requiring surgical rewiring. At follow-up (mean 3 years, range 1-6 years), 19 patients were in NYHA class I and four were in class II. Crash-BOB patients required an average of 8 extra intensive care days and 2 extra ward days. The total cost of these resources was pound164900 (including theatre time, cardiopulmonary bypass and intra-aortic balloon pump use). This was equivalent to pound7170 per life saved. CONCLUSIONS Crash-BOB occurred in 0.8% of cases and was associated with a survival to discharge of 42%, and a justifiable cost of only pound7170 per life saved. Establishing an accurate diagnosis for the cause of clinical deterioration resulting in crash-BOB intervention was important, and the need for a further period of aortic cross-clamping did not preclude a favourable outcome.
Collapse
|
283
|
Berul CI, Maguire CT, Gehrmann J, Reddy S. Progressive atrioventricular conduction block in a mouse myotonic dystrophy model. J Interv Card Electrophysiol 2000; 4:351-8. [PMID: 10936001 DOI: 10.1023/a:1009842114968] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
INTRODUCTION Myotonic dystrophy is caused by expansion of a CTG trinucleotide repeat on human chromosome 19, and leads to progressive skeletal myopathy and atrioventricular conduction disturbances. A murine model of myotonic dystrophy has been designed by targeted disruption of the myotonic dystrophy protein kinase (DMPK) gene. The DMPK-deficient mice display abnormalities in A-V conduction characteristics, similar to the human cardiac phenotype. The purpose of this study was to determine whether age-related progression of A-V block occurs in a mouse model of DMPK-deficiency. METHODS AND RESULTS Surface ECGs and intracardiac electrophysiology (EP) studies were performed in 60 immature and 90 adult homozygous (DMPK-/-), heterozygous (DMPK+/-), and wild-type (WT) DMPK+/+ control mice. Complete studies were obtained on 141 of 150 mice. The RR, PR, QRS, and QT intervals were measured on ECG. Sinus node recovery time, AV refractory periods, paced AV Wenckebach and 2:1 block cycle lengths, atrial and ventricular effective refractory periods were compared between genotypes and age groups. There were no differences in ECG intervals or EP findings in the young mutant mice, but progressive PR prolongation in older mice. The A-V conduction defects are also sensitive to DMPK gene dosage. Adult DMPK-/- mice develop 1 degrees, 2 degrees and 3 degrees A-V block, whereas DMPK+/- mice develop only 1 degrees heart block. CONCLUSION These data demonstrate that both age and DMPK dose are important factors regulating cardiac conduction in myotonic dystrophy. This mouse model of DM is remarkably similar to the human phenotype, with age-related progression in atrioventricular conduction defects.
Collapse
|
284
|
Mbewu A, Matchaba P, Reddy S, Onyebujoh P. AIDS management options for SA. S Afr Med J 2000; 90:461-3. [PMID: 10901812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
|
285
|
Reddy S, Jones AD, Cross CE, Wong PS, Van Der Vliet A. Inactivation of creatine kinase by S-glutathionylation of the active-site cysteine residue. Biochem J 2000; 347 Pt 3:821-7. [PMID: 10769188 PMCID: PMC1221021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Protein S-thiolation, the formation of mixed disulphides of cysteine residues in proteins with low-molecular-mass thiols, occurs under conditions associated with oxidative stress and can lead to modification of protein function. In the present study, we examined the site of S-thiolation of the enzyme creatine kinase (CK), an important source of ATP in myocytes. Inactivation of this enzyme is thought to play a critical role in cardiac injury during oxidative stress, such as during reperfusion injury. Reaction of rabbit CK M isoenzyme with GSSG, used to model protein S-thiolation, was found to result in enzyme inactivation that could be reversed by GSH or dithiothreitol. Measurement of GSH that is released during the thiolation reaction indicated that the maximum extent of CK thiolation was approx. 1 mol of GSH/mol of protein, suggesting thiolation on one reactive cysteine residue. Accordingly, matrix-assisted laser-desorption ionization MS confirmed that the molecular mass of CK was increased, consistent with addition of one GSH molecule/molecule of CK. Using trypsin digestion, HPLC and MS analysis, the active-site cysteine residue (Cys(283)) was identified as the site of thiolation. Reversal of thiolation was shown to be rapid when GSH is abundant, rendering dethiolation of CK thermodynamically favoured within the cell. We conclude that S-glutathionylation of CK could be one mechanism to explain temporary reversible loss in activity of CK during ischaemic injury. The maintainance of GSH levels represents an important mechanism for regeneration of active CK from S-glutathionylated CK.
Collapse
|
286
|
Hellstrom WJ, Reddy S. Application of pericardial graft in the surgical management of Peyronie's disease. J Urol 2000; 163:1445-7. [PMID: 10751854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
PURPOSE We investigated the use of Tutoplast cadaveric pericardium as an alternative material for grafting the tunica albuginea defect after Peyronie's plaque excision. MATERIALS AND METHODS A total of 11 patients with significant penile curvature interfering with sexual intercourse were evaluated after at least 12 months of conservative therapy. Preoperative evaluation in all cases included penile duplex Doppler ultrasound studies. Chemically processed and gamma irradiated pericardium was used to graft the cavernosal defect after surgical excision of the penile plaque. In 3 patients a penile prosthesis was simultaneously placed secondary to documented erectile dysfunction at duplex Doppler ultrasound evaluation. RESULTS Penile curvature resolved in all patients, allowing for normal sexual function after a mean followup of 14 months (range 9 to 19). No postoperative evidence of tissue rejection or infection was noted. In 1 patient urethro-corporal communication developed and a single penile cylinder was explanted. Another patient had a mild dorsal bulge at the site of graft placement when the prosthesis was fully inflated. CONCLUSIONS Polymeric silicone material used to provide satisfactory results in the surgical treatment of Peyronie's disease but it is no longer available for biomedical use. We demonstrate the effective use of cadaveric pericardium as a graft material for cavernosal defects after Peyronie's plaque excision. Overall patient satisfaction, absence of a second surgical incision, relative low risk and ease of surgical placement make this material ideal for the surgical treatment of this disease process.
Collapse
|
287
|
Sarkar PS, Appukuttan B, Han J, Ito Y, Ai C, Tsai W, Chai Y, Stout JT, Reddy S. Heterozygous loss of Six5 in mice is sufficient to cause ocular cataracts. Nat Genet 2000; 25:110-4. [PMID: 10802668 DOI: 10.1038/75500] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Myotonic dystrophy (DM) is an autosomal dominant disorder characterized by skeletal muscle wasting, myotonia, cardiac arrhythmia, hyperinsulinaemia, mental retardation and ocular cataracts. The genetic defect in DM is a CTG repeat expansion located in the 3' untranslated region of DMPK and 5' of a homeodomain-encoding gene, SIX5 (formerly DMAHP; refs 2-5). There are three mechanisms by which CTG expansion can result in DM. First, repeat expansion may alter the processing or transport of the mutant DMPK mRNA and consequently reduce DMPK levels. Second, CTG expansion may establish a region of heterochromatin 3' of the repeat sequence and decrease SIX5 transcription. Third, toxic effects of the repeat expansion may be intrinsic to the repeated elements at the level of DNA or RNA (refs 10,11). Previous studies have demonstrated that a dose-dependent loss of Dm15 (the mouse DMPK homologue) in mice produces a partial DM phenotype characterized by decreased development of skeletal muscle force and cardiac conduction disorders. To test the role of Six5 loss in DM, we have analysed a strain of mice in which Six5 was deleted. Our results demonstrate that the rate and severity of cataract formation is inversely related to Six5 dosage and is temporally progressive. Six5+/- and Six5-/- mice show increased steady-state levels of the Na+/K+-ATPase alpha-1 subunit and decreased Dm15 mRNA levels. Thus, altered ion homeostasis within the lens may contribute to cataract formation. As ocular cataracts are a characteristic feature of DM, these results demonstrate that decreased SIX5 transcription is important in the aetiology of DM. Our data support the hypothesis that DM is a contiguous gene syndrome associated with the partial loss of both DMPK and SIX5.
Collapse
|
288
|
Kleeberger SR, Reddy S, Zhang LY, Jedlicka AE. Genetic susceptibility to ozone-induced lung hyperpermeability: role of toll-like receptor 4. Am J Respir Cell Mol Biol 2000; 22:620-7. [PMID: 10783135 DOI: 10.1165/ajrcmb.22.5.3912] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The pollutant ozone (O(3)) induces lung hyperpermeability and inflammation in humans and animal models. Among inbred strains of mice, there is a 3-fold difference in total protein (a marker of permeability) recovered in bronchoalveolar lavage (BAL) fluid after a 72-h exposure to 0.3 ppm O(3). To determine the chromosomal locations of susceptibility genes, we performed a genome screen using recombinant inbred (RI) strains of mice derived from O(3)-susceptible C57BL/6J (B6) and O(3)-resistant C3H/HeJ (HeJ) progenitors. Each RI strain was phenotyped for O(3)-induced hyperpermeability, and linkage was assessed for 558 markers using Map Manager QTb27. A significant quantitative trait locus (QTL) was identified on chromosome 4. The likelihood ratio chi(2) statistic (16.6) for the peak of the QTL was greater than the significance threshold (16.3) determined empirically by permutation test. This QTL contains a candidate gene, Toll-like receptor 4 (Tlr4 ), that recently has been implicated in innate immunity and endotoxin susceptibility. The amount of the total trait variance explained by the QTL at Tlr4, the gene with the highest likelihood ratio statistic in the QTL, was approximately 70%. To test the role of Tlr4 in O(3)-induced hyperpermeability, BAL protein responses to O(3) were compared in C3H/HeOuJ (OuJ) and HeJ mice that differ only at a polymorphism in the coding region of Tlr4. Significantly greater protein concentrations (430 +/- 35 microg/ml) were found in OuJ mice compared with HeJ mice (258 +/- 18 microg/ml) after exposure to O(3). Furthermore, reverse transcriptase/polymerase chain reaction analysis demonstrated differential expression of Tlr4 message levels between HeJ and OuJ mice after O(3) exposure. Together, results indicate that a QTL on mouse chromosome 4 explains a significant portion of the genetic variance in O(3)-induced hyperpermeability, and support a role for Tlr4 as a strong candidate susceptibility gene.
Collapse
|
289
|
Donaldson JC, Dempsey PJ, Reddy S, Bouton AH, Coffey RJ, Hanks SK. Crk-associated substrate p130(Cas) interacts with nephrocystin and both proteins localize to cell-cell contacts of polarized epithelial cells. Exp Cell Res 2000; 256:168-78. [PMID: 10739664 DOI: 10.1006/excr.2000.4822] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Crk-associated substrate (p130(Cas), Cas) is a docking protein first recognized as having elevated phosphotyrosine content in mammalian cells transformed by v-Src and v-Crk oncoproteins. Subsequent studies have implicated Cas in the control of normal cell behavior through its roles in integrin-mediated signal transduction and organization of the actin cytoskeleton at sites of cell adhesion. In this study, we sought to gain new insight into normal Cas function by identifying previously unrecognized interacting proteins. A yeast two-hybrid screen using the C-terminal region of Cas as a bait identified the Src homology 3 (SH3) domain of the mouse "nephrocystin" protein-orthologous to a human protein whose loss of function leads to the cystic kidney disease familial juvenile nephronophthisis. The putative full-length mouse and partial canine nephrocystin sequences were deduced from cDNA clones. Additional studies using epitope-tagged mouse nephrocystin indicated that nephrocystin and Cas can interact in mammalian cells and revealed that both proteins prominently localize at or near sites of cell-cell contact in polarized Madin-Darby canine kidney epithelial cells. Our findings provide novel insight into the normal cellular activities regulated by both Cas and nephrocystin, and raise the possibility that these proteins have a related function in polarized epithelial cells.
Collapse
|
290
|
Reddy S, Karanam M, Krissansen G, Nitschke K, Neve J, Poole CA, Ross JM. Temporal relationship between immune cell influx and the expression of inducible nitric oxide synthase, interleukin-4 and interferon-gamma in pancreatic islets of NOD mice following adoptive transfer of diabetic spleen cells. THE HISTOCHEMICAL JOURNAL 2000; 32:195-206. [PMID: 10872884 DOI: 10.1023/a:1004084232446] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Beta cell destruction in NOD mice can be accelerated by adoptive transfer of diabetic spleen cells into irradiated adult NOD mice. Here mice receiving diabetic spleen cells were examined at days 0, 7, 14, 21 and at onset of diabetes for the resulting insulitis and the number of intra-islet CD4 and CD8 cells and macrophages. The progression of insulitis and the number of intra-islet CD4 and CD8 cells and macrophages were correlated with the expression and co-localization of inducible nitric oxide synthase, interferon-gamma and interleukin-4 by dual-label light and confocal immunofluorescence microscopy. Diabetes developed in 7/8 mice by 27 days following cell transfer. The insulitis score increased slightly by day 7 but rose sharply at day 14 (p = 0.001) and was maintained until diabetes. The mean number of intra-islet CD4 and CD8 cells and macrophages showed a similar trend to the insulitis scores and were present in almost equal numbers within the islets. Immunolabelling for inducible nitric oxide synthase was observed at day 7 in only some cells of a few islets but increased sharply from day 14. It was restricted to islets with insulitis and was co-localized in selective macrophages. Weak intra-islet interleukin-4 labelling was observed at days 7 and 14 but became more pronounced at day 21 and at onset of diabetes, being present in selective CD4 cells. Intra-islet labelling for interferon-gamma was first observed at day 21, but became more intense at onset of diabetes and was co-localized in a proportion of macrophages. Both cytokines were expressed in islets with advanced insulitis. Interferon-gamma staining was also observed within endothelial cells located in the exocrine pancreas. We conclude that transfer of diabetic spleen cells results in a rapid influx of CD4 and CD8 cells and macrophages within the pancreas of recipient mice. During the period of heightened insulitis, selective immune cells begin to express inducible nitric oxide synthase and the opposing cytokines, interferon-gamma and interleukin-4. Expression of these molecules becomes more pronounced immediately prior to and during the onset of diabetes.
Collapse
|
291
|
Daniels NA, Bergmire-Sweat DA, Schwab KJ, Hendricks KA, Reddy S, Rowe SM, Fankhauser RL, Monroe SS, Atmar RL, Glass RI, Mead P. A foodborne outbreak of gastroenteritis associated with Norwalk-like viruses: first molecular traceback to deli sandwiches contaminated during preparation. J Infect Dis 2000; 181:1467-70. [PMID: 10753727 DOI: 10.1086/315365] [Citation(s) in RCA: 148] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/1999] [Revised: 09/28/1999] [Indexed: 11/03/2022] Open
Abstract
In March 1998, an outbreak of acute gastroenteritis occurred among students at a Texas university. Overall, 125 ill students sought medical care. Case-control studies revealed that illness was significantly associated with eating foods from the university's main cafeteria deli bar on 9 and 10 March. Stool specimens from 9 (50%) of 18 ill students and samples of deli ham showed evidence of Norwalk-like viruses (NLVs) by reverse-transcriptase (RT) polymerase chain reaction (PCR) assay. A food handler who prepared sandwiches for lunch on 9 March reported that her infant had been sick with watery diarrhea since just before the outbreak. A stool sample from the infant was positive for NLV by RT-PCR, and the sequence of the amplified product was identical to that of amplified product from deli ham and students' stool specimens. This is the first time RT-PCR and sequence analysis have successfully confirmed viral contamination of a food item likely to have been contaminated by a food handler.
Collapse
|
292
|
Reddy S, Young B, Xue Q, Taha B, Brodnick D, Steinberg J. Review of methods to predict and detect atrial fibrillation in post-cardiac surgery patients. J Electrocardiol 2000; 32 Suppl:23-8. [PMID: 10688299 DOI: 10.1016/s0022-0736(99)90030-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Atrial fibrillation (AF) is the most common sustained arrhythmia after cardiac surgery. Postoperative AF is known to substantially lengthen hospital stay and affect patient recovery. Identification of those at risk of developing AF after surgery and early detection of AF during recovery would be extremely helpful in effective management of these patients, including targeting prophylactic therapy to prevent AF in high-risk patients. In this communication, diagnostic methods to identify those at risk of developing AF after surgery and early identification of AF before, during, and after surgery have been reviewed. Signal-averaged P wave analysis, done before surgery, identifies patients who are likely to develop AF during recovery. When combined with low ejection fraction, signal-averaged P wave can discriminate those who develop AF from those who do not. During recovery, AF can be detected early either from a detailed analysis of atrial activity in a 10-second electrocardiogram or an analysis of R-to-R intervals from an extended rhythm strip (1 minute or longer). Analysis of the 10-second electrocardiogram includes median QRST subtraction from rhythm data and detection and analysis of atrial signals in the resulting residual. AF is detected from extended rhythm strips by using a statistical model to identify the presence of characteristic irregular patterns of R-to-R intervals.
Collapse
|
293
|
Cullinane DC, Jenkins JM, Reddy S, VanNatta T, Eddy VA, Bass JG, Chen A, Schwartz M, Lavin P, Morris JA. Anterior ischemic optic neuropathy: a complication after systemic inflammatory response syndrome. THE JOURNAL OF TRAUMA 2000; 48:381-6; discussion 386-7. [PMID: 10744273 DOI: 10.1097/00005373-200003000-00003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Patients are surviving previously fatal injuries. Unique morbidities are occurring in these survivors. Anterior ischemic optic neuropathy represents a previously unrecognized cause of blindness in the trauma victim. We hypothesize that this phenomenon is caused by unique characteristics of optic edema/ pressure or decreased blood flow associated with massive resuscitation. METHODS Between November of 1991 and August of 1998, there were 18,199 admissions to our trauma center. Of this group, 350 patients required massive volume resuscitation (>20 liters infused over first 24 hours). Patients having closed head injuries, facial fractures or direct orbital trauma were excluded from study. The following variables were studied: demographics, injury severity (Injury Severity Score, highest lactate, worst base deficit, and lowest pH) crystalloid and transfusion requirements, ventilator requirements (PEEP) RESULTS: Of the 350 patients with massive resuscitation, 9 patients were diagnosed with anterior ischemic optic neuropathy (2.6%). Of these, seven patients required celiotomy (78%). Six of the seven celiotomy patients had damage control celiotomies and abdominal compartment syndrome (86%). One patient had a repair of a subclavian artery; one had a complex acetabular repair. Blindness was unilateral in five patients and bilateral in four. All nine patients had evidence of global hypoperfusion, systemic inflammatory response, massive resuscitation, and high ventilatory support; one patient required cardiopulmonary resuscitation. CONCLUSION Prone positioning is known to be associated with an increased intraocular pressure. We postulate that the combination of massive resuscitation and prone positioning will increase the incidence of anterior ischemic optic neuropathy. As such, we recommend that prone positioning for adult respiratory distress syndrome be reserved for only those patients at risk of death.
Collapse
|
294
|
Lee DH, Walker IR, Teitel J, Poon MC, Ritchie B, Akabutu J, Sinclair GD, Pai M, Wu JW, Reddy S, Carter C, Growe G, Lillicrap D, Lam M, Blajchman MA. Effect of the factor V Leiden mutation on the clinical expression of severe hemophilia A. Thromb Haemost 2000; 83:387-91. [PMID: 10744141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
To determine whether the factor V Leiden mutation is associated with decreased bleeding in individuals with severe hemophilia A, factor concentrate utilization, maximum annual number of bleeding episodes, and the prevalence of hemophilic arthropathy between carriers and non-carriers of the factor V Leiden mutation were compared. Heterozygosity for the factor V Leiden mutation was found in 6 of 137 subjects (4.4%). Carriers of the factor V Leiden mutation utilized less factor concentrate (geometric mean: 310 vs. 1185 units/kg/year) and had fewer bleeding episodes than non-carriers (proportion with 10 or fewer bleeding episodes in their worst year: 50 vs. 11%). However, the factor V Leiden mutation was not associated with the absence of arthropathy. The intron 22 inversion mutation of the factor VIII gene was tested for in a subgroup of 80 subjects, but it was not found to be a significant variable for any of the bleeding endpoints. The results of this small study are consistent with the hypothesis that the factor V Leiden mutation imparts a protective effect; however, a larger confirmatory study in which the factor VIII molecular defects can be controlled for is needed. Furthermore, most severe hemophiliacs who used fewer than 200 units/kg/year of factor concentrate or who had experienced 10 or fewer bleeding episodes per year did not carry the factor V Leiden mutation, suggesting that the proportion of severe hemophiliacs whose mild clinical course can be attributed to the factor V Leiden mutation is small.
Collapse
|
295
|
Dietz V, Vugia D, Nelson R, Wicklund J, Nadle J, McCombs KG, Reddy S. Active, multisite, laboratory-based surveillance for Cryptosporidium parvum. Am J Trop Med Hyg 2000; 62:368-72. [PMID: 11037779 DOI: 10.4269/ajtmh.2000.62.368] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Cryptosporidium parvum leaped to the attention of the United States following the 1993 outbreak in Milwaukee, Wisconsin, which sickened 400,000 people. Other outbreaks in the United States have been associated with drinking and recreational water, consumption of contaminated foods, contact with animals, and childcare attendance. Despite its public health importance, the number of people who become infected each year is not known. In 1997, active surveillance for C. parvum was added to the Foodborne Diseases Active Surveillance Network (FoodNet), a collaborative effort among the Centers for Disease Control and Prevention, selected state health departments, the U.S. Departments of Agriculture and Food and Drug Administration. During the first 2 years of surveillance, 1,023 laboratory-confirmed cases of cryptosporidiosis were detected in FoodNet (Connecticut, Minnesota, Oregon, and selected counties in California, Georgia, Maryland, and New York). The annual rate per 100,000 persons was 2.3. Sixteen percent of case-patients were hospitalized. A seasonal increase in case detection was noted in late summer among persons less than 15 years of age. These data represent the first active multistate ascertainment of laboratory-confirmed cryptosporidiosis cases and provide useful information on the burden of disease in the United States.
Collapse
|
296
|
Abstract
UNLABELLED The purposes of this article are to: (1) underscore both the importance and the difficulty of assessing clinical skills at the graduate level, (2) review both old and new assessment methods of clinical skills in an attempt to familiarize educators with current views on evaluation modalities, and (3) assess the state of clinical-skills assessment specifically in radiation oncology. A series of articles published in The Lancet in 1995, entitled "Examining the Examiner," was used as a starting point. We then conducted an extensive literature search (using MEDLINE) to find publications that examined different examination methods, old and new, that apply to the education of radiation oncology residents. Concepts critical to understanding any discussion of clinical skills evaluation methods are also reviewed. RESULTS Part I of the article provides an introduction critical to understanding the objectives of clinical-skills evaluation. Also, three older, well-established methods of clinical skills evaluation (ward evaluation, oral examination, and multiple-choice questions) are assessed. In Part II, the objective structured clinical examination (OSCE), the standardized patient (SP), and the patient management problem (PMP), all born of recent innovations in the field, are discussed. Part II concludes with a review of how the issues presented in both parts are relevant to the assessment of the radiation oncology resident. All evaluation methods that can be applied to the education of radiation oncology residents have perceived advantages and shortcomings. With the proper administration of many of these (save, perhaps, the PMP), any perceived difficulties in evaluating the clinical skills of radiation oncology residents may be addressed and diminished. Suggestions offered that are worthy of further discussion, debate, and study include establishment of a standardized "ward" examination, a formative oral examination to accompany the ACR In-Training examination, and the possible revision of the American Board of Radiology oral examination. An in-depth appraisal on the feasibility of using newer evaluation methods (OSCE, SP, etc.) is also needed. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 1-12 (2000).
Collapse
|
297
|
Reddy S. Identification and purification of the 69-kDa intracellular protease involved in the proteolytic processing of the crystal δ-endotoxin of Bacillus thuringiensis subsp. tenebrionis. FEMS Microbiol Lett 2000. [DOI: 10.1016/s0378-1097(99)00631-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
298
|
Scammell JG, Reddy S, Valentine DL, Coker TN, Nikolopoulos SN, Ross RA. Isolation and characterization of the human secretogranin II gene promoter. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2000; 75:8-15. [PMID: 10648883 DOI: 10.1016/s0169-328x(99)00269-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The goal of this study was to isolate and functionally characterize the human secretogranin II (SgII) gene promoter. SgII is a member of the granin family of proteins which are selectively expressed in neurosecretory cells. The human SgII promoter contains a consensus TATA box and cyclic AMP response element (CRE) 35 and 74 bp upstream of the transcription start site, respectively, elements also found in the mouse and rat SgII gene promoters. Transfection studies showed that 869 bp of the human SgII promoter were sufficient to confer cell type-specific expression of an SgII promoter-luciferase reporter gene in neurosecretory PC-12, GH and BE(2)-M17 cells. The activity of the human SgII promoter was also compared in three N-type, human neuroblastoma cell lines [BE(2)-M17, SMS-KAN and SH-SY5Y], which differ markedly in the level of SgII expression. SgII promoter activities in the neuroblastoma cell lines correlated not only with the levels of SgII but also the levels of the cyclic AMP response element-binding protein CREB which were highest in BE(2)-M17 cells and lowest in SH-SY5Y cells. To establish that the activity of the human SgII promoter in these neuroblastoma cell lines is dependent on the level of CREB, rat CREB was overexpressed in SH-SY5Y cells. SgII promoter activity was up to 8-fold higher in SH-SY5Y cells overexpressing CREB. These results suggest that SgII expression is a marker for neuronal differentiation in human neuroblastoma cell lines and is dependent on the level of CREB expression.
Collapse
|
299
|
Rao AD, Reddy S, Rao DS. Is there a difference between right and left femoral bone density? J Clin Densitom 2000; 3:57-61. [PMID: 10745302 DOI: 10.1385/jcd:3:1:057] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/1999] [Revised: 09/07/1999] [Accepted: 10/23/1999] [Indexed: 11/11/2022]
Abstract
Because of the known differences in bone mineral density (BMD) of the dominant and nondominant forearms, it has been customary to measure BMD of the nondominant forearm to reduce variance. However, it is less clear whether such systematic differences exist between BMD of the two hips. Accordingly, we measured BMD of both hips and the spine in 131 consecutive white women who presented to a community based private practitioner for evaluation and advice on osteoporosis. There was a highly significant correlation between BMD of the two hips at the femoral neck, trochanter, and Ward's triangle (r = 0.91, 0.93, and 0.89; p < 0.0001 for all three sites), and also between BMD at various measurement sites in the hip and the spine BMD (p < 0.0001). Although, there was no significant difference between the right and left femoral neck BMD, there were small (approximately 1-2.5%) but significant differences between BMD of the two hips at the trochanter and Ward's triangle (p = 0.008 and 0. 005, respectively). The left hip BMD was consistently higher than the right hip BMD at all measurement sites. Because of the small sample size of the left-handed persons, we were unable to determine the influence of dominant handedness on hip BMD. We concluded the following: (1) BMDs of the two hips are highly correlated at relevant measurement sites; (2) there does not appear to be a dominant hip as there is dominant forearm; (3) because of strong agreement between BMD of the two hips there is little justification to measure both hips in routine clinical practice.
Collapse
|
300
|
Lau D, Xue L, Hu R, Liaw T, Wu R, Reddy S. Expression and regulation of a molecular marker, SPR1, in multistep bronchial carcinogenesis. Am J Respir Cell Mol Biol 2000; 22:92-6. [PMID: 10615070 DOI: 10.1165/ajrcmb.22.1.3637] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
A small proline-rich protein, SPR1, is overexpressed in squamous metaplasia of bronchial epithelium. We studied the expression and regulation of SPR1 in a series of human bronchial epithelial cell lines representing a model of multistep bronchial carcinogenesis. These cell lines included a primary culture of tracheobronchial epithelial cells (HTBE), a papilloma virus-transformed tracheobronchial epithelial cell line (HBE1), a cell line selected from HBE1 by a tobacco carcinogen and a phorbol ester (HBE1-C), a simian virus-transformed bronchial epithelial cell line (BEAS-2B), and a lung carcinoma cell line (H460). Different tumorigenic potentials of these cell lines were indicated by graded levels of telomerase activity. Concomitant with squamous transformation, there was an increase in SPR1 expression in HTBE, HBE1, and HBE1-C that was reversible by vitamin A. With progression of tumorigenicity, there was a marked reduction in SPR1 expression in BEAS-2B and a total loss of expression in H460. In these latter cell lines representing advanced malignant transformation, there was a loss of up- and downregulation, respectively, by the phorbol ester and vitamin A. Transfection study with chimeric constructs of the SPR1 promoter and a reporter gene showed that the dysregulation of SPR1 expression in malignant transformation was a result of perturbation of the basal and enhancer elements of the first 162 nucleotides in the 5'-flanking promoter region of the SPR1 gene. These findings suggest an association of transcriptional dysregulation of the SPR1 gene with multistep bronchial carcinogenesis.
Collapse
MESH Headings
- Animals
- Biomarkers, Tumor/genetics
- Blotting, Western
- Carcinoma, Bronchogenic/enzymology
- Carcinoma, Bronchogenic/etiology
- Carcinoma, Bronchogenic/genetics
- Carcinoma, Bronchogenic/metabolism
- Cell Line
- Cornified Envelope Proline-Rich Proteins
- Epithelial Cells/enzymology
- Gene Expression Regulation, Neoplastic
- Genes, p53/genetics
- Genes, ras/genetics
- Humans
- Lung Neoplasms/enzymology
- Lung Neoplasms/genetics
- Lung Neoplasms/metabolism
- Membrane Proteins
- Mice
- Mice, Nude
- Mutation/genetics
- Promoter Regions, Genetic/genetics
- Protein Biosynthesis
- Proteins/genetics
- RNA, Messenger/biosynthesis
- Telomerase/metabolism
- Tumor Cells, Cultured
Collapse
|