shukoor65/lab-rag-model huggingface dataset:
Blood flow reactivity to hypercapnia in strictly unilateral carotid disease: preliminary results. To show relationship between degree of carotid arterial stenosis and cerebral blood flow reactivity (RES%) to induced hypercapnia, fluorine-18-fluoromethane and positron emission tomography (PET) was used to study 18 patients with carotid distribution transient ischaemic attacks (TIA), all free of stroke, who had angiographic-proven unilateral arterial disease. Non-involved carotid arteries were either normal or had non-stenotic plaque. Either normal arteries or nonstenotic ulcerations in the symptomatic carotid arteries were present in five of 18 (28%), ipsilateral carotid stenosis from 50-99% was present in eight of 18 (44%), and ipsilateral internal carotid occlusion was present in five of 18 (28%) patients. In comparison with 14 normal controls, all patients with symptomatic middle cerebral artery (MCA) flow territories had significantly lower mean (SEM) RES% [5.0' (0.2) vs 4.0 (0.9), p less than 0.04]. Symptomatic anterior borderzone (ABZ) RES% was also significantly lower [4.6 (0.4) vs 3.3 (0.9), p less than 0.04], than controls. In patient subgroup comparisons, the 50-99% stenosis subgroup clearly had the lowest MCA RES% [3.4 (0.2)] as well as the lowest ABZ RES% [2.8 (0.4)] on their symptomatic sides. Age, expired pCO2, mean arterial blood pressure, serum glucose, serum haematocrit and number, type and estimated duration of TIAs were not significantly different between subgroups. Linear regression showed a significant relationship between RES% and both measured percentage-stenosis (p = 0.04) and residual luminal diameter (p = 0.05) in symptomatic MCA territories. This approached significance in symptomatic ABZ regions. This preliminary data set suggests that unilateral carotid stenosis can and does result in impaired CO2 reactivity following hypercapnia.
Protein kinase C is involved in PTH-induced homologous desensitization by directly affecting PTH receptor in the osteoblastic osteosarcoma cells. We have investigated mechanisms of PTH-induced homologous desensitization reflected in the refractoriness of cAMP response to the second exposure to PTH in the clonal rat osteosarcoma cell line, UMR-106. Preincubation with 10(-7) M rat (r) PTH-(1-34) for 6 h caused the desensitization, resulting in a 65% decrease in cAMP accumulation in response to further exposure to rPTH. This desensitization was apparent at 10(-10) M rPTH and maximal at 10(-7) M rPTH. UMR-106 cells treated with protein kinase C (PK-C) activating phorbol ester, phorbol 12-myristate 13-acetate (PMA, 10(-6) M) for 6 h also induced desensitization manifested by a loss of rPTH-stimulated cAMP accumulation to 50% of that in the control cells. On the other hand, 4 alpha-phorbol 12,13-didecanoate, incapable of activating PK-C, failed to induce desensitization. Fifty micromolar H-7 (PK-C inhibitor) significantly blocked both rPTH- and PMA-induced desensitization. Thus, PK-C seemed to play a major role in rPTH-induced desensitization. Pretreatment with neither rPTH nor PMA changed the cAMP responsiveness to 10 micrograms/ml cholera toxin or 100 microM forskolin. Islet activating protein failed to influence the desensitization in this cell line. PTH receptor binding, assessed by using 125I-labeled [Nle8,Nle18,Tyr34]PTH-(1-34) as a radioligand, was decreased along with PTH receptor numbers by pretreatment with rPTH or PMA. These data indicate that rPTH-induced homologous desensitization occurs at least in part through the activation of PK-C and that PK-C directly affects PTH receptor in UMR-106 cells.
The benefit of the Hemonetics cell saver apparatus during cardiac surgery. This retrospective chart review of 155 patients having coronary artery bypass graft surgery (CABG) over a two-month period determined whether the use of a cell saver apparatus (CSA) (1) reduced or increased the requirements for homologous blood; (2) increased the incidence of post-surgical bleeding; (3) was cost-effective. Two groups of patients were identified. Group 1 (n = 99) received both CSA processed red blood cells and homologous blood components. Requirement for homologous blood products was reduced in the first 24 hr after surgery (0.5 +/- 1.0 vs 1.3 +/- 1.8 units; P less than 0.05) when compared with Group 2 (n = 56) in whom only homologous blood products were utilized. More patients in Group 1 had no transfusion requirements (45 vs 8; P less than 0.05) and there was no increased risk of major haemorrhage. When the capital costs are included, utilization of the CSA was not cost-effective. We conclude that utilisation of a CSA was safe, with no increased risk of bleeding, reduced requirements for homologous blood transfusions, but added to the cost of the procedure.
Abnormal responses to orthostatic testing in children and adolescents with recurrent unexplained syncope. Syncope in the pediatric age group is a frequent event. Most often the cause is readily apparent--i.e., orthostatic hypotension or a vasovagal event. However, there are a large number of children with frequent recurrent unexplained syncope. Neither history, physical examination, nor standard testing reveals a cause. One hundred four consecutive patients were evaluated by orthostatic testing after standard methods found no cause for the recurrent syncope. Forty-seven (44%) of these 104 patients had syncope produced by orthostatic testing. Twenty-six of the 47 (55%) became syncopal within 5 minutes of testing initiation and 21 of the 47 (45%) after 5 to 11 minutes of testing. These patients had an average decrease of 81.5 mm Hg in blood pressure and a 25 beat/min decrease in heart rate. Of 12 control subjects, none lost consciousness with standing times as long as 14 minutes. Pacing was ineffective in preventing syncope, as two patients with a previously implanted normally functioning pacemaker had recurrent syncope clinically. Syncope was also induced by orthostatic testing, with the pacemaker showing a normal response with pacing as the patient became bradycardic. The syncopal event produced by orthostatic testing occurred with a downward blood pressure trend and a narrowing of the pulse pressure without a significant increase in heart rate. This was followed by a sudden drop in blood pressure and then by bradycardia. There is a group of children and adolescents with recurrent unexplained syncope due to abnormal orthostatic control mechanisms. Orthostatic testing appears helpful in identifying these patients.
Lumbar epidural diamorphine following thoracic surgery. A comparison of infusion and bolus administration. Twenty-two patients received a single dose of diamorphine 5 mg through a lumbar epidural catheter before thoracic surgery. The patients were transferred after surgery to a high dependency unit where they were allocated randomly to receive either an infusion of epidural diamorphine at a rate of 1 mg/hour (group 1) or bolus doses of epidural diamorphine 5 mg on demand (group 2). There was no statistically significant difference between the groups in visual analogue pain scores in the first 18 postoperative hours. Arterial carbon dioxide tension was elevated in both groups and was consistently higher in group 1 than in group 2, with a statistically significant intergroup difference 12 hours after operation. Respiratory rate was not a useful index of respiratory depression. The commonest nonrespiratory side effect was urinary retention, but the incidences of this and other minor side effects were similar in the two groups.
Carcinoma of the prostate: MR images obtained with body coils do not accurately reflect tumor volume. MR imaging with a body coil is unreliable in directly demonstrating tumor spread through the prostatic capsule. However, the likelihood of extracapsular spread of prostatic cancer rises with increasing tumor volume. The aim of our study was to assess the accuracy of MR with a body coil in diagnosing capsular penetration indirectly via an estimation of prostatic tumor volumes. Twenty-six patients with proved prostatic cancer that was clinically confined to the gland underwent MR imaging before radical prostatectomy and whole-mount pathologic sectioning of the specimen. Twenty of 31 lesions prospectively outlined on the MR images corresponded to cancers outlined on the pathology slides, and tumor volumes were calculated by using a voxel summation technique. On MR, tumor volume was underestimated in 11 of 20 cases and overestimated in nine of 20 cases. Only two of 20 size estimates based on MR findings were within 10% of actual tumor volume. Overlap in MR tumor volumes was significant between lesions with and without capsular penetration at microscopy. Factors contributing to inaccuracies in measurements of tumor volume on MR images included the variable histologic make-up of the tumors. Our results show that, although knowledge of the size of a prostatic lesion is important in predicting the behavior of the tumor, MR imaging with a body coil is not reliable for accurate estimation of tumor volume.
Purification of parathyroid hypertensive factor from plasma of spontaneously hypertensive rats. Parathyroid hypertensive factor (PHF) is a newly described hypertensive factor that may be related to elevation of blood pressure in 30-40% of North American essential hypertensive patients. PHF is also found in several animal models of hypertension, including spontaneously hypertensive rats, and deoxycorticosterone acetate salt hypertensive rats. Plasma collected from spontaneously hypertensive rats (SHR) was used in the present study for purification of PHF. Plasma was dialyzed at a molecular mass cutoff of 1 kDa, and then ultrafiltered at a molecular mass cutoff of 5 kDa. PHF activity, as determined by bioassay (characteristic delayed hypertensive response in normotensive rat) was retained in the fraction that was greater than 1 kDa and less than 5 kDa. Dialyzed and ultrafiltered SHR plasma was fractionated by molecular-exclusion chromatography, either with Bio-Gel P-6 liquid chromatography, or TSK 2000 SW HPLC. The biological activity was detected in a discrete region corresponding to a molecular mass of 2.5-3 kDa. When the molecular-exclusion fraction was subsequently fractionated by reverse-phase HPLC, biological activity was located in a single discrete peak, which did not occur in plasma from normotensive rats prepared in a similar manner. The biologically active fraction of PHF was inactivated by trypsin; this and its UV spectrum indicate the presence of a peptide structure.
Nasal schwannoma. A 36-year-old man with a nasal septal mass is presented. The diagnosis of a benign neoplasm arising from peripheral nerve Schwann cells was made by excisional biopsy. A benign nerve sheath tumor may be either a schwannoma or neurofibroma. Schwannomas may be distinguished from neurofibroma by clinical and histologic criteria. Malignant degeneration and intracranial extension may complicate the course of a nasal schwannoma. Complete excision is the preferred therapy.
Essential fatty acid deficiency associated with the use of a medium-chain-triglyceride infant formula in pediatric hepatobiliary disease. Serum phospholipid fatty acid patterns were determined by gas chromatography in four infants with hepatobiliary disease receiving a formula with a high content of medium-chain-triglyceride (MCT) oil. All four infants demonstrated signs of essential fatty acid deficiency, characterized by decreased arachidonic acid and increased palmitoleic and oleic acids. All had substantial concentrations of the pathologic triene 5,8,11-eicosatrienoic acid. Three of four had decreased linoleic acid concentrations and abnormal ratios of triene to tetraene (5,8,11-eicosatrienoic acid: arachidonic acid), greater than 0.38. One patient may have experienced growth failure due to abnormal essential fatty acid status. Infants with the potential for fat malabsorption should only receive MCT-oil feedings with well above the generally recommended requirements for linoleic acid (3% of total caloric intake).
Postoperative infusional continuous regional analgesia. A technique for relief of postoperative pain following major extremity surgery. A new technique using postoperative infusional continuous regional analgesia (PICRA) for postoperative pain relief was investigated in 23 surgical patients treated by amputation (12 patients) or by limb-salvage resection operations (11 patients). Bupivacaine was delivered into peripheral nerve sheaths via catheters placed therein at the time of surgery. Only patients in whom the nerves were easily accessible were treated. Catheters were placed in the axillary sheath, the lumbosacral trunk, and the femoral nerve sheaths of patients treated with shoulder girdle and pelvic procedures (resections and amputations), and within the sciatic nerve sheath of those treated with lower extremity procedures. The anesthetic agent was delivered at controllable rates. Regional analgesia was obtained in the operative site with minimal motor or sensory decrease. To assess the efficacy of this technique, the results of this study group were compared with those of a matched group of 11 patients treated with similar surgical procedures but who received epidural morphine. Eleven of the 23 patients on PICRA required no supplemental narcotic agents. The mean level of the narcotic agents required by the remaining 13 PICRA patients was approximately one third of that required by the matched group of 11 patients receiving epidural morphine. Overall, the patients on PICRA had an 80% reduction of narcotic requirements when compared to the historical controls. The technique is reliable and can be performed by the surgeon, requiring about a ten-minute increase in operating time. It has potentially wide application in orthopedics in procedures in which the major nerves are easily accessible (e.g., pelvic fractures and revision hip surgery) and for patients with intractable pain of the extremities.
Extracellular binding sites of IgA anti-jejunal antibodies on normal small bowel detected by indirect immunoelectronmicroscopy. Patients with dermatitis herpetiformis (DH) have IgA deposition in the papillary dermis and in the lamina propria of the small bowel. In addition, most of DH patients' sera contain IgA class anti-reticulin antibodies, anti-endomysium antibodies (EMA), and anti-jejunal antibodies (JAB) during times of gluten intake. In previous studies, JAB and EMA seemed to be identical and related to the group of anti-reticulin antibodies. In the present study, pre-embedding en bloc immunoelectronmicroscopic methods were applied for analysis of the ultrastructural binding sites of JAB on monkey and rabbit small bowels. These substrates were incubated with sera from DH patients strongly positive for JAB. Simultaneous investigations with the PAP technique and with 5 nm gold-labeled protein A or second antibodies visualized the bound IgA identically: it was associated with collagen fibrils underlying the epithelial and cryptal basement membranes and with collagen fibrils around capillaries. Staining was also detected along the endomysial collagen fibrils of smooth muscle layers, around elastica and smooth muscle cells of blood vessel walls, and along collagen fibrils near smooth muscle cells in the lamina propria. Neither the peroxidase product nor gold deposition was detected directly on the fibers, but was associated with amorphous material surrounding collagen fibers of different diameters. The distribution of JAB-stained structures corresponded to the localization of reticulin network of the small bowel. Our data indicate that JAB recognize an antigen or antigens associated with an amorphous component of the reticulin-collagen structure of jejunum and may have identical binding sites, as anti-reticulin antibodies and EMA.
Amenorrhoea in women with non-alcoholic chronic liver disease. Amenorrhoea is common in women with non-alcoholic chronic liver disease, but little is known about its causes or consequences. We investigated 12 young women with non-alcoholic chronic liver disease and amenorrhoea and compared them with 11 healthy age matched controls studied in the follicular phase of the menstrual cycle. None of the patients had raised serum concentrations of follicle stimulating hormone suggesting primary gonadal failure, but the variance in serum concentrations of testosterone, oestradiol, prolactin, and luteinising hormone were significantly greater in chronic liver disease patients than control subjects (p less than 0.01). Seven of the 12 chronic liver disease patients had low serum luteinising hormone concentrations, and compared with controls these patients also had significantly reduced median values of oestradiol (64 pmol/l), testosterone (1.1 nmol/l), and follicle stimulating hormone, and were significantly underweight as assessed by skinfold thickness measurements (all comparisons p less than 0.025). In the group with chronic liver disease skinfold thickness was significantly correlated with serum luteinising hormone (p less than 0.02). The five patients with normal serum luteinising hormone had higher median values of both oestradiol (237 pmol/l) and testosterone (3.0 nmol/l) than the control subjects (oestradiol: 113 pmol/l, testosterone: 1.9 nmol/l) but were not more obese or hirsute. Amenorrhoea was unrelated to the duration or severity of liver disease. The metacarpal cortical bone area (an index of bone density) was inversely related to the duration of amenorrhoea (p less than 0.02). We conclude that amenorrhoea in women with non-alcoholic chronic liver disease arises from hypothalamic-pituitary dysfunction and can occur at any stage.
Computer-assisted superimposition of magnetic resonance and high-resolution technetium-99m-HMPAO and thallium-201 SPECT images of the brain. A method for registering three-dimensional CT, MR, and PET data sets that require no special patient immobilization or other precise positioning measures was adapted to high-resolution SPECT and MRI and was applied in 14 subjects (five normal volunteers, four patients with dementia (Alzheimer's disease), two patients with recurrent glioblastoma, and three patients with focal lesions (stroke, arachnoid cyst and head trauma]. T2-weighted axial magnetic resonance images and transaxial 99mTc-HMPAO and 201Tl images acquired with an annular gamma camera were merged using an objective registration (translation, rotation and rescaling) program. In the normal subjects and patients with dementia and focal lesions, focal areas of high uptake corresponded to gray matter structures. Focal lesions observed on MRI corresponded to perfusion defects on SPECT. In the patients who had undergone surgical resection of glioblastoma followed by interstitial brachytherapy, increased 201Tl corresponding to recurrent tumor could be localized from the superimposed images. The method was evaluated by measuring the residuals in all subjects and translational errors due to superimposition of deep structures in the 12 subjects with normal thalamic anatomy and 99mTc-HMPAO uptake. This method for superimposing magnetic resonance and high-resolution SPECT images of the brain is a useful technique for correlating regional function with brain anatomy.
Survival of patients with dementia. The evidence on survival in dementia is summarized. There are no reliable data on survival after onset of dementia or after first contact with medical services. People with dementia in outpatient clinics and nursing homes have 2-year survival rates of 75% (range 60%-95%) and 50% (range 30%-65%), respectively. Differences in survival between patients with senile dementia of the Alzheimer's type (SDAT) and multi infarct dementia (MID) are small. Women in nursing homes have a better prognosis than men (2-year survival rates, 60% vs 40%). Dementia patients have a considerable excess mortality when compared to the vital statistics. There is no evidence for improvement of survival rates during recent decades. Recommendations for future studies are made.
Percutaneous excimer laser coronary angioplasty of lesions not ideal for balloon angioplasty BACKGROUND. Excimer laser coronary angioplasty is a new, investigational technique for treating coronary artery stenoses. Initial reports have demonstrated acute efficacy and relative safety of this procedure, but have not addressed the effect of lesion type on acute success and complication rates. METHODS AND RESULTS. In the first 100 patients undergoing percutaneous excimer laser coronary angioplasty at our institution, acute laser success was obtained in 84% and procedural success was obtained in 94%. There were six acute closures during laser angioplasty and one myocardial infarction. Two patients required emergency coronary bypass surgery. Sixty-five percent of patients had lesions not ideal for balloon angioplasty because of lesion morphology (tubular, diffuse, or chronic total occlusion) or ostial location. There were 10 tubular stenoses, 29 diffuse lesions, 18 chronic total occlusions, and eight ostial lesions, including five aorto-ostial lesions. In this nonideal subgroup, the acute success rate with laser was 86% (72% of chronic total occlusions and 91% of non-totally occluded lesions), and the procedural success rate was 94%. There were three acute occlusions during laser angioplasty but no myocardial infarctions, emergency bypass surgeries, or deaths. One coronary artery perforation occurred without clinical sequelae. Laser angioplasty was successful in four of six lesions (67%) in which balloon angioplasty had failed. Laser success was obtained in 10 of 11 (91%) moderately or heavily calcified stenoses. Eight eccentric lesions and two lesions on bends were successfully treated without dissection or perforation. No side branch occlusions occurred in the 15 patients in whom one or more major branches originated within the lesion treated. Adjunctive balloon angioplasty was performed in 47% of cases, usually to obtain a larger final luminal diameter. Need for adjunctive balloon angioplasty decreased to 36% after a larger (2.0 mm) laser catheter became available. Twenty-eight percent of the 105 lesions treated were American College of Cardiology/American Heart Association classification type A, 47% were type B, and 25% were type C. Laser and procedural successes were obtained in 83% and 97% of type A, 88% and 96% of type B, and 85% and 88% of type C lesions, respectively. CONCLUSIONS. In our initial experience, excimer laser angioplasty was found to be acutely effective and safe therapy for lesions identified as not ideal for balloon angioplasty. This technique may provide a useful adjunct or alternative to balloon angioplasty in selected patients.
The postmenopausal adnexal mass: correlation between ultrasonic and pathologic findings. One hundred two postmenopausal women underwent ultrasonographic evaluation of adnexal masses before surgery. Twenty-nine (28%) had malignant tumors and 73 (72%) had benign tumors. Two of 33 patients with a "simple cyst" smaller than 5 cm in diameter by ultrasound had malignant ovarian tumors. Twenty-two of the 52 women (42%) with "complex masses" by ultrasound and five of the 17 (29%) with solid tumors had ovarian cancer. For predicting malignancy in ovarian tumors, abdominal ultrasonography had a positive predictive value of 39% and a negative predictive value of 94%. If a negative sonogram had been relied upon, 6% of malignant ovarian tumors in postmenopausal women might have been missed.