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Biomedical subjects

S K Gupta

Publications and source records attributed to S K Gupta.

At least 739 records · Page 41Linked to original sources
PubMed1985

Surface membrane glycoproteins of wild-type and differentiation-inducer-resistant HL-60 cells.

Surface membrane glycoproteins (SMGs) of cells from the parental wild-type HL-60 cell line and from three sublines variably cross-resistant to the granulocyte differentiation-inducing effects of retinoic acid (RA), dimethylsulfoxide (DMSO), and certain purine bases (6-thioguanine [6TG] or hypoxanthine) were studied by one-dimensional and two-dimensional gel electrophoresis. After both oligosaccharide (periodate/borotritide) and peptide (1,3,4,6-tetrachloro-3 alpha, 6 alpha-diphenylglycouril) ectolabeling procedures, striking common changes were noted in the gel electrophoretic patterns of the SMGs from the RA- and 6TG-resistant sublines compared to those from the wild-type HL-60 line or the DMSO-resistant subline. Most prominently, this included the presence in the RA- and 6TG-resistant cells of an apparent high molecular weight acidic glycoprotein(s) (mol wt, 200 to 285 kilodaltons [kD]; isoelectric point range [pl], 4.5 to 6.0) not observed in the wild-type or DMSO-resistant cells and, conversely, the presence of a lower molecular weight glycoprotein(s) (mol wt, 120 to 165 kD; pl, 4.2 to 5.9) in the wild-type and DMSO-resistant cells, which was absent or much reduced in the RA- and 6TG-resistant cells. These acidic SMGs did not change as a function of the induction of granulocyte differentiation. However, some other more basic SMGs varied as a function of granulocyte differentiation in both the wild-type and differentiation inducer-resistant sublines, including the loss of the transferrin receptor and the gain of a mol wt 55- to 60-kD neutrophil-associated protein. In the context of previously reported information, these results indicate (1) that the overall pattern of SMG changes in the RA- and 6TG-resistant cells closely resembles that associated with multidrug (pleiotropic) resistance to cytotoxic agents in a variety of mammalian cells; (2) that the RA/6TG resistance-associated SMG changes are not granulocyte differentiation stage-specific; and (3) that either the RA/6TG resistance-associated SMG changes are not related to the resistance mechanism or they are involved in the resistance/cross-resistance mechanism(s) for RA/purine bases but not for DMSO.

Cell Differentiation↗
PubMed1985

Spontaneous intrahepatic cutaneous biliary fistula.

A rare case of spontaneous intrahepatic cutaneous biliary fistula due to obstruction of the biliary tree by ampullary fibrosis is reported. The diagnosis was made clinically by the presence of constant flow of the bile through the fistulous opening and confirmed by roentgenography and by surgery. The definitive treatment consisted of removal of the obstruction by choledochoduodenostomy. The fistula healed spontaneously within two weeks of surgery.

Ampulla of Vater↗
PubMed1984

Paradoxical effect of antibodies against chorionic gonadotropin on BeWo choriocarcinoma cells in vitro and in vivo: evidence for heterogeneity of cell types.

Antisera raised in monkey or baboon against purified beta-subunit of human chorionic gonadotropin (beta-hCG) coupled to tetanus toxoid exert complement-dependent cytotoxic effects on BeWo choriocarcinoma cells maintained in tissue culture. The cytotoxic effect is manifested morphologically as well as by incorporation of radioactive thymidine and leucine. However, in the presence of saturating amounts of anti-beta-hCG antibodies and complement, antibodies failed to kill all of the BeWo choriocarcinoma cells. Evidence is presented to suggest that the partial and not complete cytotoxic effect of antibodies may be due to the heterogeneity of cell types, one sensitive to immune attack by anti-beta-hCG antibodies, the other resistant. Immunoenzymatic localization of hCG revealed its presence on the cell surface of only a fraction of BeWo cells. The antibody-resistant BeWo cell population had no demonstrable hCG on the cell surface. Resistant cells did not secrete hCG into the medium when cultured for up to 4 days. However, the resistant cell population, upon transplantation to the hamster cheek pouch, regained the ability to secrete hCG. Heterogeneity of cell types may explain the refractoriness of the BeWo cells transplanted to the hamster cheek pouch to an inhibitory effect of antibodies at later stages of tumor growth.

Animals↗
PubMed1984

Inadequacy of the noninvasive hemodynamic evaluation of percutaneous transluminal angioplasty.

The role of noninvasive hemodynamic tests in the evaluation of percutaneous transluminal angioplasty success or failure was studied. The ankle-brachial pressure index and pulse volume recording amplitude were measured before and after 37 iliac and 46 femoropopliteal angiographically successful percutaneous transluminal angioplasties. Immediate evidence of hemodynamic improvement was seen in 53 percent of angiographically successful dilatations using the ankle-brachial pressure index and in 60 percent using the pulse volume recording amplitude alone. A better correlation was seen when improvement was noted on either test but was still only 71 percent. Twelve primary iliac percutaneous transluminal angioplasties were considered to be successful immediately by angiography, yet no hemodynamic improvement was recorded. Nine primary iliac percutaneous transluminal angioplasties, however, had continued clinical success and limb viability. Twelve angiographically successful femoropopliteal percutaneous transluminal angioplasties also showed no improvement in hemodynamic values, yet three have continued clinical evidence of patency. Thus, although noninvasive hemodynamic tests are important and must be carried out, they are only one of many ways to assess the effectiveness of angioplasty.

Adult↗
PubMed1984

Evaluation of graft patency utilizing the ankle-brachial pressure index and ankle pulse volume recording amplitude.

To determine femoropopliteal graft patency, the ankle-brachial pulse index and the ankle pulse volume recording amplitude were measured. Fourteen healthy volunteer subjects were tested on two occasions over 24 hours (ankle-brachial pressure index 1.14+:-0.16, change 0.03+:-0.05; ankle pulse volume recording amplitude 25+:-7 mm, change 5+:-4 mm). In the second control group, hemodynamic function in the unoperated limb was studied before and after surgery in 40 patients undergoing infrainguinal bypass on the contralateral side (preoperative ankle-brachial pressure index 0.66+:-0.3, change 0.02+:-0.12; preoperative ankle pulse volume recording amplitude 8+:-7 mm, change 1+:-3 mm). After 119 patent femoropopliteal bypasses ankle-brachial pressure index and ankle pulse volume recording amplitude increased by 0.41+:-0.26 and 11+:8 mm, respectively.

Ankle↗
PubMed1984

Gonadal hormone-dependent changes in the concentrations of sialic acid and fructose in the seminal glomus and of glycogen in the oviduct of the Indian pied myna.

Sialic acid and fructose contents of the seminal glomus and glycogen content of the oviduct were estimated in the normal, gonadectomized, and gonadectomized plus sex steroid (testosterone in male and estradiol in female birds)-treated Indian pied myra, Sturnus contra contra. The levels of these substances declined on the sixth day after gonadectomy; sex steroid administration increased the level of these substances in gonadectomized birds. The findings indicate that the concentration of these substances in the accessory reproductive organs in the Indian pied myna are influenced by the respective gonadal hormones.

Animals↗
PubMed1984

Quantitative assessment of outflow resistance in lower extremity arterial reconstructions.

Graft patency is thought to correlate with resistance in the runoff bed or outflow resistance. However, accurate measurement of this parameter has been difficult. A simple and reproducible method for direct measurement of outflow resistance following completion of the distal anastomosis of a bypass graft has been developed. This method employs injection of a fixed amount of normal saline through the proximal end of the graft and measurement of the resulting integrated pressure increment by an analog computer. Division of this pressure integral by the volume injected is a measure of the outflow resistance expressed in resistance units (mm Hg/ml/min). The median outflow resistance in 31 femoropopliteal bypasses was 0.29 units with a range of 0.08-1.38 units. The median outflow resistance in 33 femorodistal bypasses was 0.7 units with a range of 0.18-2.34 units. All bypasses with an outflow resistance of 1.1 units or less remained patent for 3 months. There were 51 grafts in this group (30 femoropopliteal; 21 femorodistal) and their outflow resistance ranged from 0.08 to 1.1 units. All bypasses with an outflow resistance of 1.2 units or higher thrombosed within the first postoperative month. There were 13 grafts in this group (1 femoropopliteal; 12 femorodistal) and their outflow resistance ranged from 1.2 to 2.38 units. Eight of the 13 grafts that failed originally were subjected to thrombectomy, which was uniformly unsuccessful. Although this method does not yet allow bypass surgery to be denied to any patient, it does define a group of patients in whom thrombectomy will not be effective and should not be attempted.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1984

Components of outflow resistance and their correlation with graft patency in lower extremity arterial reconstructions.

We have used a simple reproducible method to measure total outflow resistance (OR) and its proximal and distal components in 101 bypasses (46 femoropopliteal [FP] and 55 femorodistal [FD]). All bypasses with a distal OR greater than 1.2 mm Hg/ml/min failed within 3 months and all with distal OR less than 1.2 mm Hg/ml/min remained patent for at least 3 months. To evaluate the contribution of vasospasm to OR and its role in graft failure, 60 bypasses (29 FP, 31 FD) had OR measurements before and after local infusion of papaverine hydrochloride (60 mg). Within 3 months, nine grafts (all FD) occluded and 51 remained patent. All nine failures had distal OR greater than 1.2 mm Hg/ml/min before papaverine infusion. After infusion, the mean percentage decrease in both total and distal OR for all grafts was 30% and 31%, respectively. However, there was no significant difference between these papaverine-induced decreases in OR and 3-month graft failure or success. Moreover, in three bypasses, even though papaverine lowered the distal OR from greater than 1.2 to less than 1.2 mm Hg/ml/min, early occlusion occurred. In six grafts (1 FP, 5 FD) when total and distal OR before and after papaverine was greater than 1.2 mm Hg/ml/min, the graft was extended to a second distal artery as a sequential bypass. These six grafts have remained patent over 3 months. Thus measurement of OR and particularly distal OR is a most accurate predictor of early graft success or failure. Pharmacologic manipulation does not enhance the predictive value of the OR measurement. OR measurements also help to select those FD bypass cases in which extension to a second distal artery as a sequential bypass improves patency.

Aged↗
PubMed1984

Management of angioplasty complications, unsuccessful procedures and early and late failures.

Limb-salvage was the indication for 90% of 206 attempted PTAs in 175 patients between 1976 and 1982. Life-table patency rates at 4 years for the angiographically successful iliac PTA and femoropopliteal PTA were 78% and 50%, respectively. PTA of eight iliac, seven femoropopliteal, nine tibial, and two subclavian arteries and one autogenous saphenous vein graft (ASV) were unsuccessful. Of these, 17 subsequently underwent successful bypass grafts and five required below-knee amputations. Ten iliac, 37 femoropopliteal, four tibial, and two ASV graft PTAs failed. Of 20 repeat attempts at PTA, only two have achieved long-term patency. Appropriate surgery allowed limb salvage in 23 of 36 early failures (less than 3 months) and 12 of 14 late failures (greater than 3 months), and usually consisted of the same operation that would have been performed had PTA not been attempted. Fifty-two complications were classified according to the method of treatment. Fourteen warranted surgery, but in 10 this was successfully achieved by the same operation that would have been required had PTA not been performed.

Adult↗
PubMed1984

5-HIAA in cerebrospinal fluid of patients with status epilepticus.

Cerebrospinal fluid concentration of 5-hydroxyindolacetic acid (5-HIAA) was determined in 15 patients soon after recovery from status epilepticus. Similarly, patients with generalised epilepsy and persons without epilepsy, serving as controls, were also studied. The level of 5-HIAA was significantly reduced in all epileptic patients with or without status epilepticus, as compared with the nonepileptic control group. However, there was no statistical difference between patients with status epilepticus and those with generalised epilepsy. Among patients with epilepsy, low 5-HIAA levels in CSF could not be correlated with frequency or severity of seizures, or with antiepileptic drugs. A link between CSF 5-HIAA and susceptibility of humans to epilepsy may indicate a possible future therapeutic approach.

Adolescent↗