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The present study was designed to study RBC aggregability in type 1 and type 2 DM by a new method based on the dielectric properties of disperse systems. This dielectric method has a significantly higher sensitivity to detect enhanced RBC aggregation in DM than other methods. Aggregability is increased in type 1 DM and even more markedly in type 2 diabetic patients. The enhanced RBC aggregation in type 1 diabetes was significantly correlated with the levels of HbA1C, cholesterol and triglycerides. However, no correlation between metabolic control and RBC aggregability was found in type 2 DM. The in vitro addition of non-toxic, low molecular weight dextran improves the high RBC aggregation in diabetes type 2. In the future, low molecular weight dextran may be used in DM patients clinically to lower the risk for vascular complications, after the problem of filtration is solved. [ABSTRACT FROM AUTHOR]

Background: Complete tooth loss is a significant global oral health issue, particularly impacting older individuals with lower socioeconomic status. Computer-assisted technologies enhance oral healthcare access by the elderly. Despite promising in vitro reports on digital denture materials, evidence from randomized clinical trials (RCTs) is lacking to verify their performance. This cross-over RCT will investigate whether 3D-printed implant-retained mandibular overdentures (IMO) are more satisfactory for edentulous seniors than those made through traditional methods., Methods/design: We will recruit 26 completely edentulous participants (any sex/gender) based on the following eligibility criteria: age ≥ 60 years, no tooth extraction in the past 12 months, two implants in the lower jaw, and need for new dentures in both jaws. Each participant will receive two denture pairs, either manufactured by 3D printing or traditionally, to be worn in a random order. A timeline of 3 months with each denture pair will be considered for outcome assessment (total: 6 months). Patient satisfaction with dentures will be measured by the McGill Denture Satisfaction Questionnaire. We will evaluate other patient-reported outcomes (including oral health-related quality of life) as well as clinician-assessed quality and cost. At the end of the trial, participants will choose which denture pair they wish to keep and interviewed about their experiences with the 3D-printed IMO. The quantitative and qualitative data will be incorporated through an explanatory mixed-methods strategy. A final quantitative assessment will happen after 12 months with the preferred IMO to assess the long-term performance and maintenance needs., Discussion: This mixed-methods RCT will explore patient experiences with 3D-printed IMOs, aiming to assess the potential for altering clinical practice and dental public health policies. Our results will inform policies by showing whether 3D printing offers comparable outcomes at lower costs, facilitating greater access to oral care for the elderly., Trial Registration: ClinicalTrials.gov, NCT06155630, Registered on 04 December 2023. https://classic., Clinicaltrials: gov/ct2/show/NCT06155630., (© 2024. The Author(s).)

Kidneys play an important role in retinol turnover. We postulated that retinol homeostasis is disturbed in diabetic nephropathy. The aim of this research was to study the effect of kidney impairment on urinary excretion and on serum concentrations of retinol in type 2 diabetes mellitus patients. For this purpose, 41 type 2 diabetes patients and 9 sex -and age-matched healthy subjects were enrolled. Serum and urinary retinol and retinol-binding protein (RBP) were assessed by high-pressure liquid chromatography and enzyme-linked immunosorbent assay, respectively. The study showed that 17 out of 41 diabetic patients (41.5%) and none of the controls excreted retinol in urine (P < 0.02). Retinol excretion in the urine in these patients was 1.5-fold more prevalent than hypercreatininemia. Urinary retinol significantly correlated with clinically diagnosed nephropathy (P = 0.02). All but one of the patients with hypercreatininemia excreted retinol in the urine. Serum retinol and RBP in patients with hypercreatininemia were higher than in controls (P < 0.002). Values of urinary retinol, unlike urinary RBP, albumin and total protein, did not overlap between patients and controls. Our results indicate that (i) urinary retinol is a specific sign of tubular damage in type 2 diabetic patients and (ii) urinary retinol enables a more clear-cut identification of proximal tubule dysfunction in type 2 diabetes patients than urinary RBP or albumin.

Purpose: We evaluated the efficacy of a combined chemoradiation therapy protocol for the primary treatment of primary invasive carcinoma of the male urethra., Materials and Methods: From January 1991 to December 2006, 18 patients with invasive carcinoma of the male urethra referred to our institution were treated with a chemoradiation therapy protocol, consisting of 2 cycles of 5-fluorouracil (1,000 mg/m(2)) on days 1 to 4 and days 29 to 32, and mitomycin-C (10 mg/m(2)) on days 1 and 29 with concurrent external beam radiation therapy (45 to 55 Gy in 25 fractions during 5 weeks) to the genitalia, perineum, and inguinal and external iliac lymph nodes. Kaplan-Meier curves were constructed to assess overall, disease specific and disease-free survival., Results: The stage and node distribution was T2N0 in 2 patients (11%), T3N0 in 8 (44%), T4N0 in 2 (11%), TXN1 in 1(6%) and TXN2 in 5 (28%). The most prevalent histology was moderately (7 of 18 patients or 39%) or poorly (10 of 18 or 56%) differentiated squamous cell carcinoma (17 of 18 or 95%). Overall 83% (15 of 18) of the patients had a complete response to the primary chemoradiation therapy protocol, and the 5-year overall and disease specific survival rates were 60% and 83%, respectively. Five-year disease-free survival rates after chemoradiation therapy and after chemoradiation therapy with salvage surgery were 54% and 72%, respectively. The 3 nonresponders died of disease after undergoing salvage surgery and 5 of the 15 complete responders (30%) had recurrence. Complex urethral reconstruction was required in 3 of 10 patients (30%) who had prolonged disease-free survival., Conclusions: The chemoradiation therapy protocol is an alternative primary treatment modality for invasive urethral carcinoma. It enables an unprecedented potential for organ preservation.

The present study was designed to study RBC aggregability in type 1 and type 2 DM by a new method based on the dielectric properties of disperse systems. This dielectric method has a significantly higher sensitivity to detect enhanced RBC aggregation in DM than other methods. Aggregability is increased in type 1 DM and even more markedly in type 2 diabetic patients. The enhanced RBC aggregation in type 1 diabetes was significantly correlated with the levels of HbA(1C), cholesterol and triglycerides. However, no correlation between metabolic control and RBC aggregability was found in type 2 DM. The in vitro addition of non-toxic, low molecular weight dextran improves the high RBC aggregation in diabetes type 2. In the future, low molecular weight dextran may be used in DM patients clinically to lower the risk for vascular complications, after the problem of filtration is solved.

Over the past 10 years, men with prostate cancer have received earlier diagnoses and are undergoing prostatectomy and/or radiation therapy with curative intent; however, many men have increasing prostate-specific antigen (PSA) levels without evidence of local progression or metastatic disease during the first 2 years after definitive local therapy. Optimal treatment of men with PSA-only recurrent prostate cancer has not been established. This ongoing phase II trial is evaluating docetaxel (70 mg/m(2) administered intravenously over 1 hour on day 2 every 21 days for four cycles) and estramustine (10 mg/kg/d orally on days 1 to 5 every 21 days for four cycles) followed by bicalutamide and goserelin acetate in men with increasing PSA levels after prostatectomy and/or radiation therapy. Patients received pretreatment with dexamethasone, and after the third patient enrolled, patients received warfarin for prophylaxis against thrombosis. Colony-stimulating factor support was allowed. In preliminary results, 11 of 15 patients completed protocol chemotherapy; 12 of 15 patients achieved complete response (ie, normalization of PSA) after four cycles of chemotherapy. In addition, testosterone levels were reduced to the castrate range in all patients after chemotherapy. The regimen was generally well tolerated, and toxicities were mostly hematologic, with grade (3/4) neutropenia reported in approximately half of patients. Preliminary results of this phase II trial are encouraging, and enrollment is ongoing., (Copyright 2001 by W.B. Saunders Company.)

Breast cancer management requires a multidisciplinary approach that is tailored to the patient's stage at presentation, desire for breast conservation or reconstruction, estimation of risk of recurrence, and assessment of the benefits and toxicities of potential adjuvant therapies. At the Lahey Clinic Medical Center, breast surgeons, plastic surgeons, radiation oncologists, and medical oncologists staff the Breast Cancer Treatment Clinic, and work closely together to formulate treatment plans that will optimize the likelihood for cure with an acceptable cosmetic result. This involves careful preoperative work-up, surgical axillary staging, breast irradiation in the setting of breast conservation, and selection of chemotherapy or hormonal therapy if appropriate. Newer aspects of breast cancer care, including sentinal lymph node biopsy, postmastectomy radiation therapy, expanded use of hormonal therapy in younger women, new agents and chemotherapy combinations, and autogenous reconstruction techniques, have become an essential part of the multidisciplinary clinic approach.

Mutations in the androgen receptor (AR), that alter steroid hormone specificity have been identified in a series of androgen-independent prostate cancers. To address the functional properties of these mutant ARs that may have contributed to their selection in vivo, responses to a series of steroid hormones and antiandrogens were assessed. CV-1 cells were cotransfected with wild-type or mutant ARs and a luciferase reporter plasmid regulated by an androgen-responsive element. Dose-response curves were analyzed for 5alpha-dihydrotestosterone, the most active androgen in normal prostate, and androstenedione, a major androgen derived from the adrenals. Although the mutant ARs responded to both of these steroids, the responses were equivalent to or less than the wild-type AR. In contrast, responses to flutamide, a competitive antagonist of the wild-type AR, were markedly increased by three of the mutations. Similar responses were observed with a second antiandrogen, nilutamide. Bicalutamide, another antiandrogen related to flutamide, remained an antagonist for these mutant ARs. Finally, flutamide was observed to be a weak partial agonist of the wild-type AR in this system. These results indicate that flutamide used in conjunction with androgen ablation therapy for prostate cancer may select for tumor cells with flutamide-inducible ARs.

Purpose: Rhodopsin is a zinc-binding protein. We investigated the effect of low concentrations of zinc on the initial phosphorylation of rhodopsin., Methods: Dark-adapted bovine rod outer segments (ROS) were incubated with (gamma 32P) ATP and 5 mM magnesium in the presence and absence of micromolar amounts of zinc. The ROS were exposed to light to initiate phosphorylation under conditions which allow only limited initial phosphorylation., Results: We found that zinc enhanced the rhodopsin phosphorylation apparent on autoradiographies by several fold. Phosphorylation reactions conducted in the presence of potent phospho-opsin phosphatase inhibitors show a comparable zinc-enhanced phosphorylation of rhodopsin. Under our reaction conditions, ROS membranes also appear more red upon initial exposure to light when zinc is present., Conclusions: Zinc can increase initial rhodopsin phosphorylation, apparently acting at the substrate rhodopsin and not at relevant phosphatases or rhodopsin kinase. How zinc binding to rhodopsin might increase its ability to serve as a substrate for phosphorylation is under investigation.

8-Azidoadenosine triphosphate labeled in the alpha or gamma position with 32P was used as a photoaffinity reagent for identifying ATP binding sites on the external surface of intact rat brain synaptosomes. As revealed by autoradiography of sodium dodecyl sulfate-polyacrylamide gel electrophoretic patterns. UV irradiation of intact synaptosomes in the presence of the above radioactive compounds at 5-10 microM resulted in the formation of several major radioactive conjugates with approximate molecular masses of 29, 45/46, 58, and 93 kDa. Minor bands of 20, 39, 52/54, 82/84, 120, and 140 kDa were also consistently labeled in these experiments. The possibility that labeling of these proteins was due to the presence of contaminating subcellular particles or intrasynaptosomal proteins was excluded. The major 8-azidoadenosine [alpha-32P]triphosphate-labeled protein complex of approximately 45/46 kDa was resolved into several subbands that are labeled differently depending on the type of divalent cations added to the photoaffinity reaction. In the presence of magnesium only, the major labeled band appeared at 45 kDa. With calcium, two additional subbands (43 and 46 kDa) could be distinguished. In the presence of 1 mM EDTA, a band at 44 kDa was labeled within this ATP-binding complex. The labeling pattern of the subbands of this 45/46-kDa complex is consistent with these bands being extracellular ATP-binding proteins on the surface of the synaptosome.

Background: Metastatic prostate cancer is a leading cause of cancer-related death in men. The rate of response to androgen ablation is high, but most patients relapse as a result of the outgrowth of androgen-independent tumor cells. The androgen receptor, which binds testosterone and stimulates the transcription of androgen-responsive genes, regulates the growth of prostate cells. We analyzed the androgen-receptor genes from samples of metastatic androgen-independent prostate cancers to determine whether mutations in the gene have a role in androgen independence., Methods: Complementary DNA was synthesized from metastatic prostate cancers in 10 patients with androgen-independent prostate cancer, and the expression of the androgen-receptor gene was estimated by amplification with the polymerase chain reaction. Exons B through H of the gene were cloned, and mutations were identified by DNA sequencing. The functional effects of the mutations were assessed in cells transfected with mutant genes., Results: All androgen-independent tumors expressed high levels of androgen-receptor gene transcripts, relative to the levels expressed by an androgen-independent prostate-cancer cell line (LNCaP). Point mutations in the androgen-receptor gene were identified in metastatic cells from 5 of the 10 patients examined. One mutation was in the same codon as the mutation found previously in the androgen-independent prostate-cancer cell line. The mutations were not detected in the primary tumors from of the two patients. Functional studies of two of the mutant androgen receptors demonstrated that they could be activated by progesterone and estrogen., Conclusions: Most metastatic androgen-independent prostate cancers express high levels of androgen-receptor gene transcripts. Mutations in androgen-receptor genes are not uncommon and may provide a selective growth advantage after androgen ablation.

Rod outer segments (ROS) from rat were purified on Percoll gradients. These ROS had intact plasma membranes since they were impermeable to small molecules. Protein phosphorylation in the purified ROS was studied after the plasma membrane was disrupted by freeze/thawing. [gamma-32P]ATP was used as phosphate donor. ATP concentration, time, temperature, and light or dark adaptation were varied in the assays. The 32P-labeled proteins were separated by polyacrylamide gel electrophoresis and autoradiographed. Rhodopsin was the dominant phosphorylated protein, and the addition of adenosine cyclic 3',5'-phosphate (cAMP) or guanosine cyclic 3',5'-phosphate (cGMP) (10(-4) M) did not qualitatively alter the ROS phosphorylation pattern. The only cyclic nucleotide effect we could establish in these experiments was the inhibition of rhodopsin phosphorylation by cGMP. This inhibition did not appear to be competitive with ATP since cAMP was much less inhibitory than cGMP and the phosphorylation in the presence of cGMP reached a plateau at a much lower level than in control conditions. Hypotheses implying an involvement of protein phosphorylation/dephosphorylation in dark adaptation have been formulated [Miller, J. A., & Paulsen, R. (1975) J. Biol. Chem. 250, 4427-4432; Kuhn, H., McDowell, J. H., Leser, K. H., & Bader, S. (1977) Biophys. Struct. Mech. 3, 175-180]; we suggest that cGMP may control this process through the modulation of the extent of inhibition of phosphorylation of the visual pigment.

Adenylate kinase activity (ATP:AMP-phosphotransferase; EC 2.7.4.3) was studied in various subcellular fractions of rat brain tissues. Because of the presence of other adenosine nucleotide-utilizing enzymes, adenylate kinase activity was assayed in both the forward and reverse directions by using coupled enzyme systems and by using a specific adenylate kinase inhibitor, P1,P5-di(adenosine-5') pentaphosphate. As expected, the highest specific adenylate kinase activity (2.89 mumol/min/mg of protein) was detected in the cytosolic brain fraction. However, substantial enzyme activity (0.68 mumol/min/mg) was also found in the intact synaptosomal fraction isolated on Percoll/sucrose gradients. The increased specific enzyme activity of purified synaptosomes and the differences found between the kinetic parameters of the membrane-bound and cytosolic enzyme forms suggest that the synaptosomal adenylate kinase activity cannot be attributed to the small amount of contaminating cytosol present in our preparations. The adenylate kinase enzyme adhered to purified synaptic plasma membranes and was not released by washings with isoosmotic sucrose medium. The facts that the adenylate kinase enzyme activity could be measured in intact synaptosomal preparations and that both its substrates and its inhibitors do not cross intact plasma membranes support the possibility that the synaptosomal adenylate kinase is an ecto-enzyme.

The developmental pattern of rhodopsin phosphorylation in degenerative (rdle homozygote) and normal (rd/+ heterozygote) mouse retina has been investigated. The results indicate that rhodopsin levels are comparable in the 2 retinas up to about 10 days of age but that rhodopsin phosphorylation is not. The phosphorylation of rhodopsin is substantially reduced in the degenerative retina during development. This abnormality may be an expression of the rd lesion. The rhodopsin kinase/phosphatase system, the G protein, and the visual pigment are all involved in the modulation of cGMP-phosphodiesterase activity in normal retinas. A defect in any of these components could account for the reduced level of cGMP-phosphodiesterase activity in rd retinas, resulting in cGMP accumulation and subsequent photoreceptor degeneration.

Rat rod outer segments (ROSs) were isolated by vortexing retinas and separating the detached components on performed Percoll gradients. A lighter band of 20 x 10(6) unsealed ROSs per ten retinas, and a heavier band of 60 x 10(6) sealed ROSs per ten retinas were obtained from each 12 ml gradient. The yield of sealed ROSs (but not unsealed ROSs) was increased up to twofold in the presence of the specific cysteine protease inhibitor, Ep-475. Aprotinin, pepstatin, PMSF, TPCK and EGTA plus EDTA had no effect. These results indicate that during isolation, ROSs are vulnerable to damage by cysteine protease activity either from damaged retinal cells or from within.

The rod photoreceptor outer segment maintains a remarkable morphology. Two of the proteins which have been implicated in the maintenance of this structure are the 240 kDa spectrin-like protein, and the 220 kDa glycoprotein often referred to as the rim protein. We have probed rat rod outer segment proteins with light-activated (azido-labeled) radioactive nucleotides and found a nucleotide binding site(s) on the rim protein which has a preference for guanine nucleotides. Binding to this site is stimulated by the divalent cations zinc, manganese and magnesium, but not calcium. This site is under investigation and may play a role in stabilizing protein structure.

An ATP-hydrolysing activity on the external surface of intact synaptosomes from chicken forebrain has been investigated. The observed ATPase activity was not due to leakage of the intracellular ATPase activities, of artefacts resulting from breakage of the nerve endings during the incubation and isolation periods, or to possible contamination by other subcellular particles. Disruption of the synaptosomes resulted in an approximately 2.5-fold increase of the basal, Mg2+-dependent ATPase activity, suggesting that the plasma membrane was acting as permeability barrier to the substrate. ATP hydrolysis was maximal (0.8 mumol Pi/min/mg protein) at pH 8.2 in a medium containing either Mg2+ or Ca2+ ions. Ouabain (0.2 mM) and oligomycin (2 micrograms/mg protein) had no appreciable effect on this ATPase activity. Kinetic studies of the enzyme revealed an apparent Km value of ATP of approximately 4 x 10(-5) M. These data are consistent with the view that the observed ATP hydrolysis was being catalysed by an ectoenzyme, i.e., an enzyme in the plasma membrane of the nerve endings with its active site facing the external medium. The rapid hydrolysis of the released ATP is a suspected function for this ecto-ATPase.

Proteins from the all-cone retina of the lizard Anolis carolinensis were phosphorylated using [gamma 32P] ATP, separated by SDS-PAGE and detected by autoradiography. Several proteins incorporated 32P. Exposure of the retinal homogenates to light brought about a dramatic increase in phosphorylation of the protein(s) with a molecular weight nearly identical to that of rat rhodopsin. It is likely that these proteins are the cone visual pigments, and that they incorporate phosphate when bleached by light. Increasing the time of the phosphorylation reaction from 1 to 30 min led to an increase in the amount of incorporation of labeled phosphate by the putative cone visual pigments, but changing the temperature from 4 degrees C to 20 degrees C decreased it. The amount of phosphate incorporation was substantially increased by NaF, a phosphatase inhibitor. This latter finding, along with the changes in incorporation of 32P with increased temperature, suggest that a phosphoprotein phosphatase is active in the lizard retina. The cation requirements, as well as the effects of cyclic nucleotides on light-induced phosphorylation of retinal lizard proteins, were also investigated.

Intact synaptosomes isolated from mammalian brain tissues (rat, mouse, gerbil, and human) have an ATP hydrolyzing enzyme activity on their external surface. The synaptosomal ecto-ATPase(s) possesses characteristics consistent with those that have been described for ecto-ATPases of various other cell types. The enzyme has a high affinity for ATP (the apparent Km values are in the range of 2-5 X 10(-5) M), and is apparently stimulated equally well by either Mg2+ or Ca2+ in the absence of any other cations. The apparent activation constant for both divalent cations is approximately 4 X 10(-4) M in all mammalian brain tissues studied. The involvement of a non-specific phosphatase in the hydrolysis of externally added ATP is excluded. ATP hydrolysis is maximal in the pH range 7.4-7.8 for both divalent cation-dependent ATPase activities. Dicyclohexylcarbodiimide, 2,4-dinitrophenol, trifluoperazine, chlorpromazine, and p-chloromercuribenzoate (50 microM) inhibit the ecto-ATPase, whereas ouabain (1 mM) and oligomycin (3.5 micrograms X mg-1 protein) show little or no inhibition of this enzyme activity. Inhibitor data suggest that the Mg2+- and Ca2+-dependent ecto-ATPase may represent two different enzymes on the surface of synaptosomes.

With the use of an antiserum raised to peanut agglutinin (PNA)-binding protein(s) from human retinas, we have identified a glycoprotein that has the same subunit molecular weight (135,000) as human interphotoreceptor retinol-binding protein (IRBP) on human retinal protein transblots, and, like IRBP, is localized in the interphotoreceptor matrix surrounding both rods and cones. We show that this PNA-binding protein is not IRBP by comparing the binding patterns of antiserum to the PNA-binding protein to binding patterns obtained with antisera to bovine and monkey IRBP.

ATP has important roles in the vertebrate rod outer segment (ROS) physiological response to light. One of them is the quench of light-activated cGMP-phosphodiesterase activity. How ATP quenches PDE is not established; however, leading hypotheses favor the intervention of a 48-kDa ATP-binding protein and/or an ATP-utilizing rhodopsin kinase in this reaction. We have investigated the binding of [alpha 32P]8-azido-ATP to rat ROS proteins in the presence and absence of various divalent cations and competitive nucleotides. An event we have detected which might further clarify the role of ATP in PDE inactivation is a zinc-induced binding of azido-ATP to rhodopsin. Manganese is also effective in inducing this binding, while magnesium and calcium are not. The azido-ATP binding is eliminated by the addition of ATP, but not GTP, UTP, cGMP, or cAMP. A nucleotide-binding site on the rim protein is also suggested from these studies.