Activation of (Na++K+)-ATPase by long-chain fatty acids and fatty acyl coenzymes A

Long-chain unsaturated fatty acids and fatty acyl CoA derivatives activated (Na++K+)-ATPase at suboptimal, but not optimal, ATP concentrations. Activation was obtained within a narrow range of fatty acid concentrations; higher acid levels inhibited the enzyme. The various CoA esters, however, activated with K0.5 values in the range of 0.15-10 microM; and with no inhibitory effects at concentrations up to 100 microM. Palmitoyl CoA, binding reversibly to a regulatory site, reduced K0.5 of ATP from 0.37 mM to 0.17 mM; and changed the Hill coefficient of the substrate-velocity curve from 0.86 to 0.63. These compounds may be physiological regulators that desensitize the function of this enzyme to diminishing ATP levels.     

Midlevel Personnel in Obstetrics and Gynecology Practices: Cost-Effectiveness and Consumer Benefits

Two private obstetrics-gynecology practices, in adjacent Northwest cities, which employ midlevel nurse practitioners for routine obstetric and gynecologic care were the subject of this study. At site A fees charged by the practitioner were 44 percent less than those for identical services provided by the physician. This was an attempt to pass cost savings directly to patients. At site B, fees were the same for both physician and practitioner, yielding a significant net income to the practice. At this latter site a proportion of the income was passed to patients by not increasing office fees for the years 1975 (when the practitioner was hired) through 1977, during which time the average fees of ten other physicians increased. The study shows that the use of midlevel personnel in private offices is highly cost-effective and profitable. Ideally, this profit can be passed on to patients by reduced overall office fees.     

CD-30(Ki-1)-positive anaplastic large cell lymphoma in a pleural effusion. A case report with diagnosis by cytomorphologic and immunocytochemical studies.

BACKGROUND: Reports on cytodiagnosis of Ki-1-positive anaplastic large cell lymphoma (ALCL) are rare. This report describes one such case diagnosed by cytologic examination of a pleural effusion and confirmed by immunocytochemistry. CASE: An 87-year-old male presented with breathlessness, fever and a cough. Computed tomographic scan of the thorax showed a small, right, pleura-based nodule with infiltration of the immediate surroundings in addition to a massive, right-sided pleural effusion. Cytologic examination of pleural fluid revealed a heterogeneous population of cells comprising small mature lymphocytes, and numerous medium and large atypical lymphoid cells having frequent nuclear irregularity. Occasional very large cells resembling Reed-Sternberg cells or multinucleated cells with a horseshoe or wreathlike arrangement of nuclei (doughnut cells) were also present. Cytomorphology was suggestive of Ki-1 anaplastic large cell lymphoma (ALCL). Immunocytochemistry revealed intense positivity for CD-30, positivity for LCA and EMA in a variable number of cells and a negative result for cytokeratin except for occasional cells. CONCLUSION: Cytologic examination of pleural fluid can serve as a useful tool for the initial diagnosis of Ki-1-positive ALCL.     

Plasma membrane proteome of adhesion‐competent endometrial epithelial cells and its modulation by Rab11a

Human endometrial epithelium (EE) is composed of a multitude of proteins, amongst which those localized on the plasma membrane [plasma membrane proteins (PMPs)] are of critical relevance in the early stages of implantation. Evidence supports the key role of few PMPs in implantation. However, many remain unidentified, as efforts have not been made till date to generate the plasma membrane proteome of human EE cells, using a gel‐free approach. This study presents a protein catalog of the PMP enriched fraction of Ishikawa cell line; often used as an in vitro model for embryo‐adhesive EE. Liquid chromatography with tandem mass spectrometry identified 3,598 proteins. Of these, 1,963 proteins were annotated for their membrane localization. Of 1,963 proteins, 1,321 were found to have a transmembrane domain and 43 proteins had glycophosphatidylinositol (GPI) anchor. Extensive data mining revealed endometrial expression of 943 proteins reported in humans and/or rodents. Further, quantitative alterations were observed in the plasma membrane proteome on the perturbation of intracellular trafficking. Silencing of Rab11a (known for its role in plasma membrane organization) expression caused alteration in the abundance of 74 proteins. Caveolin‐1 and EpCAM levels were reduced whereas Rab4a abundance increased in the PMP extracts of Rab11a deficient cells, compared with control cells. Briefly, the study reports the identity of several novel plasma membrane‐localized proteins. A major spin‐off of the study is the identification of novel proteins trafficked by Rab11a to the plasma membrane. Targeted analysis of novel PMPs may reveal their specific roles in endometrial receptivity and implantation.     

PTTG and cancer

Pituitary tumor transforming gene (pttg) is a recently isolated oncogene that is expressed in most of the tumors. Overexpression of pttg results in an increase in cell proliferation, induces cell transformation in vitro, and promotes tumor formation in nude mice. The gene encodes a protein of 202 amino acids with no significant homology with other known proteins. The protein is a multi domain consisting of a transactivation domain, domain required for ubiquitin-mediated proteolysis and a DNA binding domain. pttg protein is bestowed with a multitude of functions and seems to be involved in most of the important mechanisms of cell proliferation, differentiation and signaling. Given the number of processes that are involved in the manifestation of cancer, it thus becomes mandatory to study the role of this potent oncogene in relation to the processes of cell survival, death and functioning.     

Flow injection chemiluminescence determination of acetochlor and cartap-HCl in freshwater samples using an acidic KMnO4–rhodamine-B reaction system

A flow injection (FI) methodology using the acidic potassium permanganate (KMnO₄)–rhodamine-B (Rh-B) reaction with chemiluminescence (CL) detection was established to determine acetochlor and cartap-HCl pesticides in freshwater samples. Experimental parameters were optimized, and Chelex-100 cationic exchanger mini column and solid-phase extraction (SPE) were used as phase separation techniques. Linear calibration curves were observed for the standard solutions of acetochlor and cartap-HCl over the ranges 0.005–2.0 mg L⁻¹ [y = 1155.8x + 57.551, R² = 0.9999 (n = 8)] and 0.005–1.0 mg L⁻¹ [y = 979.76x + 14.491, R² = 0.9998 (n = 8)] with LODs and LOQs of 7.5 × 10⁻⁴ and 8.0 × 10⁻⁴ mg L⁻¹ (3σ blank) and 2.5 × 10⁻³ and 2.7 × 10⁻³ mg L⁻¹ (10σ blank), respectively, with an injection throughput of 140 h⁻¹. These methods were used to estimate acetochlor and cartap-HCl with or without the SPE procedure, respectively, in spiked freshwater samples. Results obtained were not significantly different at a 95% confidence level to those of other reported methods. Recoveries for acetochlor and cartap-HCl were obtained over the ranges 93–112% (RSD = 1.9–3.6%) and 98–109% (RSD = 1.7–3.8%), respectively. The most probable CL reaction mechanism was explored.     

Comparative electrophoretic studies of proteins and enzymes of some Brassica species

Summary A considerable amount of variation with respect to soluble proteins and esterase isoenzyme pattern was observed between different species of Brassica. Naturally occurring amphidiploids had comparable proteins and isoenzyme patterns to either one or both of the parental species. The species relationship based on percentage homology of protein and esterase bands revealed that B. nigra and B. campestris are the parental species of B. carinata and not B. nigra and B. oleracea, as suggested on the basis of cytological studies. Elimination of a pair of chromosomes might have resulted into 2n=34 in the case of B. carinata. Further studies are needed to confirm this view. The peroxidase and catalase isoenzyme patterns did not show much variation in different species and amphidiploids.