Cutaneous mantle cell lymphoma detected with Ga-67 Citrate.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to M Patel.
Explore the source record for details and available documents.
PURPOSE: The objective of this investigation was to compare the accuracies of bone and Ga-67 scintigraphy and magnetic resonance imaging (MRI) for diagnosing spinal osteomyelitis and to determine the optimal radionuclide approach to this disorder. METHODS: Twenty-two patients, with 24 sites of possible spinal osteomyelitis, who underwent three-phase bone scintigraphy with SPECT, Ga-67 scintigraphy with SPECT, and MRI with and without contrast were included in this retrospective review. Bone scans were interpreted as three-phase studies, delayed planar images alone, delayed planar plus SPECT, and SPECT alone (to identify uptake patterns). Sequential bone/ Ga-67 images were interpreted as planar and as SPECT studies. Planar and SPECT Ga-67 images were also interpreted alone. Precontrast MRI studies were used to identify osteomyelitis, whereas postcontrast images were used to identify soft tissue infection. RESULTS: Eleven sites of spinal osteomyelitis were identified. Tracer uptake in two contiguous vertebrae, as noted on SPECT, was the most accurate bone scan criterion for detecting spinal osteomyelitis (71 %). SPECT bone/Ga-67 was significantly more accurate (92%) than both planar bone/Ga-67 (75%) and bone SPECT (P = 0.15 and P = 0.2, respectively). SPECT Ga-67 was as accurate as SPECT bone/Ga-67 and as sensitive as MRI (91 %); the radionuclide study was slightly but not significantly more specific (92% vs. 77%) than MRI. Of 11 sites of extraosseous infection, 10 were identified on MRI, 9 on SPECT Ga-67, 7 on planar Ga-67, and none on bone scintigraphy. CONCLUSIONS: Spinal osteomyelitis and accompanying soft tissue infection can be diagnosed accurately with a single radionuclide procedure: SPECT Ga-67. This procedure can be used as a reliable alternative when MRI cannot be performed and as an adjunct in patients in whom the diagnosis is uncertain.
3-Deoxy-D-manno-octulosonate 8-phosphate (KDO8P) synthase catalyzes the biosynthesis of an essential component of the lipopolysaccharide of all Gram-negative bacteria. The structure and mechanism of KDO8P synthase are being actively studied as this enzyme represents an important target for antibiotic therapy. The structure of the Escherichia coli KDO8P synthase in cubic crystals (space group I23) has recently been determined and the enzyme shown to be a tetramer of identical subunits. However, this information is challenged by biochemical studies, which suggest that the enzyme behaves in solution as a homotrimer. Here, the preparation and preliminary X-ray analysis of monoclinic crystals of KDO8P synthase are reported. The crystals belong to space group P2(1), with unit-cell parameters a approximately 50, b approximately 140, c approximately 74 A, beta approximately 105 degrees. The structure of KDO8P synthase in the monoclinic crystal form was determined by molecular replacement, using as a search model one of the subunits of the enzyme in the cubic crystals. A tetramer of KDO8P synthase with 222 local symmetry is also present in the asymmetric unit of the P2(1) crystals, with a solvent content of 43%. The observation that the same quaternary structure of KDO8P synthase is observed in two different crystal forms belonging to distinct crystal systems (monoclinic and cubic) suggests that a tetramer is the native form of the enzyme.
BACKGROUND: The purpose of neuroimaging of a patient with new onset of seizures is to demonstrate cause and explore the prognosis. It was recently recommended that emergency brain computed tomography (CT) be performed only in adult seizure patients with an increased likelihood of life-threatening lesions, i.e., those with new focal deficits, persistent altered mental status, fever, recent trauma, persistent headaches, history of cancer, history of anticoagulation, or suspicion of acquired immunodeficiency syndrome. The objective of this study was to determine the diagnostic utility of emergency brain CT in children who present to the emergency department with new onset of seizures. METHODS: A 1-year retrospective chart review of all children who presented to the emergency department of the Schneider Children's Hospital with a new onset of seizures and who underwent CT of the brain, excluding children with simple febrile seizures. RESULTS: Sixty-six patients, 34 boys and 32 girls with a mean age of 4.9 years, qualified for inclusion in the study. Fifty-two patients (78.8%) had normal CT results and 14 patients (21.2%) had abnormal CT results. Seizure cause was considered cryptogenic in 33 patients, of whom 2 (6%) had abnormal CT results; neither patient required intervention. Seizure cause was considered symptomatic in 20 patients, of whom 12 (60%) had abnormal CT results (p < 0.0001). In two patients with abnormal CT scans (both acute symptomatic), the imaging findings were of immediate therapeutic significance and were predictable from the clinical history and the physical examination. None of the 13 patients with complex febrile seizure cause had an abnormal CT scan. Patients with partial convulsive seizures were more likely to have abnormal CT scans than patients with generalized convulsive seizures, but the difference was not statistically significant. CONCLUSIONS: The routine practice in many pediatric emergency departments of obtaining brain CT scans for all patients with new onset of nonfebrile seizures is unjustified. History and physical examination are sufficient to identify those patients for whom such studies are likely to be appropriate. Emergent CT is not indicated for patients with no known seizure risk factors, normal neurological examinations, no acute symptomatic cause other than fever, and reliable neurological follow-up. For these patients, referral to a pediatric neurologist for further workup, including electroencephalography and the more diagnostically valuable magnetic resonance imaging, would be more appropriate.
Chronic granulomatous disease (CGD) is an inherited disorder of the NADPH oxidase in which phagocytes are defective in generating superoxide and downstream microbicidal reactive oxidants, leading to recurrent life-threatening bacterial and fungal infections. Xanthine oxidase (XO) is another enzyme known to produce superoxide in many tissues. Using the p47(phox-/-) mouse model of CGD, we evaluated the residual antibacterial activity of XO. Clearance of Burkholderia cepacia, a major pathogen in CGD, was reduced in p47(phox-/-) mice compared to that in wild-type mice and was further inhibited in p47(phox-/-) mice by pretreatment with the specific XO inhibitor allopurinol. Hepatic B. cepacia burden was similar in the two genotypes, but allopurinol significantly reduced net hepatic killing and killing efficiency only in p47(phox-/-) mice. Clearance and killing of intravenous Escherichia coli was intact in p47(phox-/-) mice and was unaffected by pretreatment with allopurinol. In CGD, XO may contribute to host defense against a subset of reactive oxidant-sensitive pathogens.
Two cases of jejunal strictures caused by Histoplasma capsulatum in AIDS patients are presented. Both patients were intravenous drug abusers. One patient, who was being treated for Pneumocystis carnii pneumonia, presented with jejunal perforation and the other presented with lower gastrointestinal bleeding and intestinal obstruction. On exploration, both patients were found to have jejunal strictures; one had intestinal perforation, and the other had intestinal obstruction with ulcers and strictures resulting in gastrointestinal bleeding. In areas where it is endemic, histoplasmosis is rarely disseminated. Dissemination is most commonly seen in immunosuppressed patients. Dissemination and extrapulmonary histoplasmosis is now included in the case definition of AIDS.
Kir1.1 (ROMK1) is inhibited by hypercapnia and intracellular acidosis with midpoint pH for channel inhibition (pK(a)) of approximately 6.7. Another close relative, Kir4.1 (BIR10), is also pH sensitive with much lower pH sensitivity (pK(a) approximately 6. 0), although it shares a high sequence homology with Kir1.1. To find the molecular determinants for the distinct pH sensitivity, we studied the structure-functional relationship using site-directed mutagenesis. An NH(2)-terminal residue (Lys-53) was found to be responsible for the low pH sensitivity in Kir4.1. Mutation of this lysine to valine (K53V), a residue seen at the same position in Kir1. 1, markedly increased channel sensitivity to CO(2)/pH. Reverse mutation on Kir1.1 (V66K) decreased the CO(2)/pH sensitivities. Interestingly, mutation of these residues to glutamate greatly enhanced the pH sensitivity in both channels. Other contributors to the distinct pH sensitivity were histidine residues in the COOH terminus, whose numbers are fewer in Kir4.1 than Kir1.1. Mutation of two of these histidine residues in Kir1.1 (H342Q/H354N) reduced CO(2)/pH sensitivities, whereas the creation of two histidines (S328H/G340H) in Kir4.1 increased the CO(2)/pH sensitivities. Combined mutations of the lysine and histidine residues in Kir4.1 (K53V/S328H/G340H) gave rise to a channel that had CO(2)/pH sensitivities almost identical to those of the wild-type Kir1.1. Thus the residues demonstrated in our current studies are likely the molecular basis for the distinct pH sensitivity between Kir1.1 and Kir4.1.
20-Hydroxyeicosatetraenoic acid (20-HETE) is a cytochrome P-450 4A (CYP4A) metabolite of arachidonic acid (AA) in human and rabbit lung microsomes and is a dilator of isolated human pulmonary arteries (PA). However, little is known regarding the contribution of P-450 metabolites to pulmonary vascular tone. We examined 1) the effect of two mechanistically distinct omega- and omega1-hydroxylase inhibitors on perfusion pressures in isolated rabbit lungs ventilated with normoxic or hypoxic gases, 2) changes in rabbit PA ring tone elicited by 20-HETE or omega- and omega1-hydroxylase inhibitors, and 3) expression of CYP4A protein in lung tissue. A modest increase in perfusion pressure (55 +/- 11% above normoxic conditions) was observed in isolated perfused lungs during ventilation with hypoxic gas (FI(O(2)) = 0.05). Inhibitors of 20-HETE synthesis, 17-oxydecanoic acid (17-ODYA) or N-methylsulfonyl-12,12-dibromododec-11-enamide (DDMS), increased baseline perfusion pressure above that of vehicle and amplified hypoxia-induced increases in perfusion pressures by 92 +/- 11% and 105 +/- 11% over baseline pressures, respectively. 20-HETE relaxed phenylephrine (PE)-constricted PA rings. Treatment with 17-ODYA enhanced PE-induced contraction of PA rings, consistent with inhibition of a product that promotes arterial relaxation, whereas 6-(20-propargyloxyphenyl)hexanoic acid (PPOH), an epoxygenase inhibitor, blunted contraction to PE. Conversion of AA into 20-HETE was blocked by 17-ODYA, DDMS, and hypoxia. CYP4A immunospecific protein confirms expression of CYP4A in male rabbit lung tissue. Our data suggest that endogenously produced 20-HETE could modify rabbit pulmonary vascular tone, particularly under hypoxic conditions.
OBJECTIVE: To determine whether a computer-based method for recording standardized assessment of neglect identifies abnormalities in the 'process' as well as in the 'outcome' of such tasks. DESIGN: Prospective sequential assessment of patients admitted to a stroke rehabilitation unit. SUBJECTS: All consecutive patients with right-sided cerebrovascular accident confirmed on computerized tomography (CT) scan including 30 patients with neglect, 57 patients without neglect. An age-matched control group of 13 subjects. INTERVENTION: All patients were tested using the standard Rivermead Behavioural Inattention Test (BIT) and by computer recording of two standard tests for assessing neglect (line bisection and Albert's test). Age-matched controls were tested using computer recording of the two standard tests. MAIN OUTCOME MEASURES: Neglect was defined using the BIT with a cut-off score of 129. Computer recording measured the 'outcome' of tasks, i.e. the deviation from midline and omissions in cancellation, as well as the 'process' of tasks, i.e. time between cancellations, components of cancellation time including premovement, movement and drawing time, and the starting point for cancellation. RESULTS: The computer recording identified significant differences in 'outcome' and 'process' which distinguished neglect from non-neglect patients. There were significant differences between non-neglect patients and age-matched controls with regard to 'process' measures but not with regard to 'outcome' measures. CONCLUSIONS: Computer recording of standard tests for assessing neglect identifies novel impairments with regard to the process of carrying out tasks. These impairments may be used to investigate changes in neglect with time, the response of neglect to treatment and to explore further the neuropsychological changes associated with neglect in stroke patients.
Foot complications in diabetics often lead to amputation. Ulceration is the most common complication in the diabetic forefoot and underlies more than 90% of cases of pedal osteomyelitis. The diagnosis of osteomyelitis is, nevertheless, difficult, and imaging is an important part of the work-up. Plain radiographs, although useful for anatomical information, are neither sensitive nor specific. Three-phase bone scintigraphy is sensitive but not specific. Labelled leucocyte scintigraphy and MRI are both useful and are complementary to one another. Labelled leucocyte scintigraphy is valuable for diagnosis as well as follow-up of pedal osteomyelitis. MRI offers exquisite anatomical detail, which is invaluable for guiding surgical management. The principal complication in the mid and hind foot is the neuropathic or Charcot joint. Although infection of the neuropathic joint is infrequent, its diagnosis is difficult. The extensive bony changes that accompany this disorder severely diminish the value of radiography and bone scintigraphy. It is not always possible to distinguish the marrow oedema of neuropathy from that of osteomyelitis and the role of MRI in the evaluation of this entity is still uncertain. Uptake of labelled leucocytes in the absence of infection may occur and is owing, at least in part, to haematopoietically active marrow. Combined leucocyte/marrow scintigraphy holds considerable promise for identifying the infected Charcot joint.
BACKGROUND: Acute upper respiratory infections are common in children who attend child care, and preventing transmission of disease in this setting depends on actions by child care staff. We set out to discover whether transmission of respiratory infections in child care could be reduced by improved infection control procedures. METHODS: We performed a cluster, randomized, controlled trial of an infection control intervention conducted in child care centers in 1 city in Australia. The intervention was training of child care staff about transmission of infection, handwashing, and aseptic nosewiping technique. Implementation of the intervention was recorded by an observer. Illness was measured by parent report in telephone interviews every 2 weeks. RESULTS: There were 311 child-years of surveillance for respiratory symptoms. By multivariable analysis, there was no significant reduction in colds in intervention center children across the full age range. However, a significant reduction in respiratory illness was present in children 24 months of age and younger. When compliance with infection control practices was high, colds in these children were reduced by 17%. CONCLUSIONS: This trial supports the role of direct transmission of colds in young children in child care. The ability of infection control techniques to reduce episodes of colds in children in child care was limited to children 24 months of age and under.
BACKGROUND: Diarrheal infections are common in children who attend child care, and preventing transmission of disease in this setting depends on actions by child care staff. We set out to discover whether transmission of gastrointestinal infections in child care could be reduced by improved infection control procedures. METHODS: We performed a cluster randomized, controlled trial of an infection control intervention conducted in child care centers for 1 city in Australia. The intervention was training of child care staff about transmission of infection and handwashing and focused on both staff and child behavior. Implementation of the intervention was recorded by an observer. Illness was measured by parent report in telephone interviews every 2 weeks. RESULTS: There were 311 child-years of surveillance for diarrheal episodes. The rate of episodes of diarrhea was 1.9 per child-year in intervention centers and 2.7 per child-year in control centers. Multivariable analysis showed that diarrheal episodes were significantly reduced in intervention center children by 50%. However, the impact of the intervention was confined to children over 24 months of age. For those centers in which children's compliance with handwashing was high, diarrheal episodes were reduced by 66%. CONCLUSIONS: This trial supports education about infection control, for staff and children in child care, as a means of reducing transmission of diarrhea. Reduction in episodes of diarrhea in children in child care was limited to children over 24 months of age.
OBJECTIVE: Our purpose was to evaluate thick-section reformatted helical CT of the brain base as a technique for reducing skull base-related artifacts and to compare it with conventional CT. MATERIALS AND METHODS: Twenty-three patients with suspected intracranial abnormalities related to the brain base, as determined either by clinical examination or at the time of imaging, were evaluated with contrast-enhanced conventional CT of the brain (5-mm collimation, 140 kVp, 170 mA, 2-sec rotation time) and reformatted helical CT (1-mm collimation, 1.5 pitch, 120 kVp, 220 mA). Helical sections were reformatted to a thickness of 5 mm by a volume-averaging algorithm using a computer workstation. Three observers retrospectively and blindly reviewed the images and qualitatively scored artifacts at the foramen magnum, middle cranial fossa, anterior cranial fossa, interpetrous region, and internal occipital protuberance. Image graininess and observer confidence were also scored. Paired statistical analyses using score differences in each patient were possible. RESULTS: Reformatted helical CT reduced skull base-related artifacts across all five anatomic regions (p < 0.05). The foramen magnum showed the greatest reduction in artifacts and the anterior cranial fossa the least. Image graininess was increased on reformatted CT compared with conventional CT (p < 0.05), but observer confidence remained higher for reformatted CT (p < 0.05). Total additional scan time was 3.15 +/- 0.38 min with 5.3 +/- 1.2 min required for reformatting. CONCLUSION: Reformatted CT significantly decreases skull base-related artifacts in the brain, improving confidence in evaluation of the brain base and adding an average of only 8.45 +/- 1.6 min of scanning and processing time to each examination.
UNLABELLED: The addition of a brief alpha interferon regimen to each CHOP induction cycle, plus one year of alpha interferon thrice weekly maintenance therapy, has no early effect on response rates or survival in patients with Intermediate or High grade cell NHL. BACKGROUND: The CHOP (Cyclophosphamide, Adriamycin. Vincristine, Prednisone) regimen is the most widely used first-line therapy for patients with Intermediate or High Grade (IG/HG) non-Hodgkin's lymphoma (NHL). Alpha 2b interferon (INF) enhances response rates and improves survival in low-grade NHL. The International Oncology Study Group (IOSG) conducted a prospective randomized study comparing CHOP alone or combined with INF in patients with IG/HG-NHL. The primary study aim was to compare the objective response rates in these patient cohorts. PATIENTS AND METHODS: Patients with a confirmed diagnosis of measurable NHL of International Working Formulation (IWF) groups D to H histology were randomized to receive CHOP alone or CHOP with 5Mu INF s.c. for 5 days on days 22 to 26 of each 28 day cycle with INF 5 million units (Mu) given three times per week subcutaneously for 52 weeks in those patients who responded to CHOP plus INF. RESULTS: The overall response rates were equivalent in both groups: CHOP alone (214 patients) 81% (complete 55%, partial 26%); CHOP plus INF (221 patients) 80% (complete 54%, partial 26%). At 36 months, the actuarial survival rate was equivalent in both groups. CONCLUSIONS: There is no apparent early advantage in terms of response or survival conferred by adding the study INF regimen to CHOP therapy for patients with IG/HG-NHL.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
We sought to determine the safety, efficacy, and outcome of percutaneous cholecystostomy (PC) in all patients undergoing the procedure at our institutions. We reviewed 53 consecutive cases of acute cholecystitis seen at our hospitals over 5.5 years in which PC was performed at the initial treatment. Follow-up was obtained by chart review and telephone questionnaire. Acute cholecystitis was the primary admitting diagnosis in 18 cases. In the remaining 35, cholecystitis developed during hospitalization. All patients were considered high surgical risks on the basis of the presence of comorbid conditions. The gallbladder was successfully catheterized under radiologic guidance in all patients and with no immediate procedure-related morbidity. Acute cholecystitis resolved in 44 of 53 patients (83%), whereas nine patients (17%) did not improve clinically after PC and died during the same hospitalization. A total of 33 (62%) eventually survived hospitalization. Elective cholecystectomy was done in 25 patients with no mortality. After cholecystectomy, three of these patients subsequently died of other causes, whereas 22 are alive. Eight patients did not undergo cholecystectomy because of underlying medical conditions or because they had acalculous cholecystitis. These patients remained free of biliary problems after removal of their cholecystostomy tube, but two have subsequently died of nonbiliary conditions. Percutaneous cholecystostomy is a safe, effective treatment for high-risk patients with acute cholecystitis. Cholecystostomy can be followed by elective cholecystectomy at a later time if the patient's condition permits or by expectant conservative management in patients who have had acalculous cholecystitis or have a very high mortality risk with surgery.
BACKGROUND: Guidelines to improve standards of care for hypertension and diabetes were disseminated by the National Department of Health in 1996 but have generally not been implemented by health professional in local primary care. A strategy for the adoption and implementation of the Guidelines was developed in collaboration with health professionals in primary care. OBJECTIVES: The development of a structured record, with prompts for the management of diabetes and hypertension according to the Guidelines. SETTING: Three community health centres (CHCs) in the Western Cape. PARTICIPANTS: Doctors and nurses managing patients with diabetes and hypertension. METHODS: A draft of the structured record was developed at a single-pilot CHC in the Western Cape. Focus group discussions established the core requirements for a structured record. Process, result and structural indicators in line with the national Guidelines were considered for inclusion in the draft record. This draft record was then piloted at two other CHCs. Comments from semi-structured interviews and pre- and post-test evaluation questionnaires were used to compile the final instrument. RESULTS: Eleven doctors and 8 nurses participated in the development of the final instrument. Important considerations in the design were a single-page, user-friendly format, tick-boxes to reduce writing, prompts, provision for sequential recording, target setting, and compatibility with the Guidelines. The final instrument was piloted and elicited a favourable overall response. CONCLUSION: The structured record simplifies the application of the Guidelines and the systematic recording of processes of care. The effectiveness of the Guidelines will be evaluated further in a randomised control trial using the structured record.