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PubMed1978

Studies on regulatory functions of malic enzymes. V. Comparative studies of malic enzymes in bacteria.

Screening of four malic enzymes--NAD-linked enzyme [EC 1.1.1.38], NAD, NADP-linked enzyme [EC 1.1.1.39], NADP-linked enzyme [EC 1.1.1.40], and D-malic enzyme--was carried out with cell-free extracts of the following 16 strains of bacteria by the aid of Sepharose 6B column chromatography: 9 strains of enteric bacteria, 3 strains of Pseudomonas, Alcaligenes faecalis, Agrobacterium tumefaciens, Rhodospirillum rubrum, and Clostridium tetanomorphum. All the strains tested contained at least one malic enzyme. The NADP-linked enzyme activity was found in all the strains except C. tetanomorphum, the NAD-linked enzyme activity in 12 strains--8 strains of enteric bacteria, 2 strains of Pseudomonas, Ag. tumefaciens, and C. tetanomorphum--and D-malic enzyme activity in 4 strains--A, aerogenes (IFO 3319 and 12059), Ps. fluorescens, and R. rubrum. The NADP-linked and NAD-linked enzyme activities of two strains of Pseudomonas were not separated by the chromatography. The available evidence suggested that the NAD, NADP-linked enzyme was not present in these 16 strains. The comparative studies of molecular, enzymatic, and serological properties of the malic enzymes in these 16 strains revealed a close similarity of the same types of malic enzymes among enteric bacteria.

Alcaligenes↗
PubMed1976

A comparative study of the pineal complex in the deep-sea fishes Bathylagus Wesethi and Nezumia liolepis.

The pineal complexes of two deep-sea fishes, Bathylagus wesethi (family Bathylagidae) and Nezumia liolepis (family Macrouridae), were studied with both light and electron microscopy. Receptor and supportive cells were identified in the pineals of both species. The presence of receptor cells suggests that the pineals function in photoreception. Ganglion cells could be identified only in B. wesethi. A dorsal sac and a paraphysis were found in B. wesethi; both structures are absent in N. liolepis. Several trends were found when the results of this study were compared with those of a study on the pineal complex of another deep-sea fish, the myctophid Triphoturus mexicanus (McNulty and Nafpaktitis, 1976). Two of these trends, which are correlated with the vertical distributions of the species studied, suggest an increase in the photosensitivity of the pineals. These are: 1) an increase in the average number of outer segment lamellar membranes per receptor cell, and 2) an increase in the ratio of receptor cells to nerve fibers in the pineal stalks. A functional relationship between the dorsal sac, paraphysis, and pineal central lumen was suggested. The relationship may involve secretory activities.

Animals↗
PubMed1979

Biochemistry of intraerythrocytic parasites. II. Comparative studies in carbohydrate metabolism.

Comparative studies were carried out on the glucose catabolism of mouse erythrocytes infected with Plasmodium berghei, Plasmodium yoelii, Babesia rodhaini, Babesia microti and Anthemosoma garnhami, as well as on uninfected erythrocytes and reticulocytes. The results showed that there was little qualitative difference between the glucose utilization and lactate production of the parasites although quantitative differences between malaria parasites and piroplasms were observed. The rate of glucose utilization of the infected cells was at least an order of magnitude higher than the rate for uninfected erythrocytes. Reticulocytes were also shown to have higher rates of glucose utilization and lactate production than uninfected erythrocytes.

Animals↗
PubMedDate not supplied

Irrigation vs. natural evacuation of left colostomy: a comparative study of 340 patients.

A comparative study of two methods of managing left colostomy (irrigation and natural evacuation) was carried out on 340 patients who were examined and interviewed at the Stoma Rehabilitation Clinic of the Institute of Surgical Pathology of the University of Padua. Ninety-two per cent of patients who irrigated their colostomies gained fecal continence. No patient who irrigated his colostomy had any cutaneous problem, and this group had significantly better results in preventing leakage of gas and odors compared with those patients using natural evacuation. For most patients who irrigated, the ability to predict or control bowel movements overcame fears of "being dirty" and related psychological problems. These patients also had more normal social and working lives than did those patients not irrigating their colostomies. Only one patient in our series had a colonic perforation, and any chance of a repeat incident will probably disappear with the cone-shaped catheters now available. The authors conclude that in properly selected patients, irrigation is the method of choice for management of left colostomy.

Aged↗
PubMed1977

A comparative study of maprotiline (Ludiomil) and viloxazine in the management of depressed patients in general practice.

A double-blind, comparative, multicentre study comparing the efficacy and tolerability of maprotiline (Ludiomil) and viloxazine as antidepressants in general practice usage is described. Progress was measured at weekly intervals over the 4-week trial duration using a modified Hamilton Rating Scale and patient self-assessment visual analogue scales. A total of 127 patients were randomized into two groups; 63 patients being allocated maprotiline and 64 patients being allocated viloxazine. Of the patients receiving maprotiline, 12 withdrew during the course of the study compared to 9 patients receiving viloxazine. Maprotiline appeared to be superior to viloxazine on the sleep and sadness scales and some evidence to show it to be better also on the tension scale. Whilst the trend favoured maprotiline, the two drugs did not appear to be significantly different on either the doctors' or the patients' assessments. There was little to choose between the drugs in terms of side-effects or ultimate patient tolerability and preference.

Adjustment Disorders↗
PubMed1977

Effects of Solanum malacoxylon extract on rachitic chicks. Comparative study with vitamin D3.

A comparative study of the effects of vitamin D3 and of a partially purified extract of Solanum malacoxylon has been carried out in rachitic chicks. Vitamin D3 and Solanum malacoxylon increased intestinal calcium absorption and serum calcium levels. They normalized the bone water and ash content. Vitamin D3 produced an increase of serum phosphate while Solanum malacoxylon further decreased the already low phosphate values. Vitamin D3 significantly increased the body weight increment of rachitic chicks, but Solanum malacoxylon did not. It appears that Solanum malacoxylon duplicates certain actions of vitamin D but lacks its phosphate-regulating and growth-promoting actions.

Alkaline Phosphatase↗
PubMedDate not supplied

Factors influenced on prognosis of reconstructive surgery for peripheral arterial occlusion: comparative study between arteriosclerosis obliterans and thromboangiitis obliterans.

Reconstructive surgery was carried out in 93 patients of ASO and TAO. Factors influenced on prognosis were studied being compared with ASO and TAO. Cumulative 5-year patency was 60% in ASO and 25% in TAO. Distal patency was shown by total score given in each site of arteriogram. Patency rate was well correlated with combinated factors such as total score of arteriogram and back flow at site of surgery. Period from onset of symptom to surgery and site of operation also correlated with patency statistically, though total serum cholesterol, ischemic time at reconstructive surgery, and amount of bleeding at operation did not relate to prognosis. Causes of early failure and special problems of late failure in TAO were studied.

Arteriosclerosis Obliterans↗
PubMed1978

Some frontiers in comparative studies of the renin-angiotensin system.

A prospective survey on the comparative studies of the renin-angiotensin system (RAS) was made at the final session of the Japan-U.S. Cooperative Seminar, held on November 14--19, 1977, at Jichi Medical School, Tochigi-ken, Japan. Strategies and tactics of the research have been clarified. In morphological studies, the strategy is to clarify structure of the juxtaglomerular apparatus in representative species of vetebrate classes. In chemical studies, each component of the RAS must be established in each vertebrate class. Since we now know the existence of severel new angiotensins in vertebrates, their amino-acid sequences must be determined. They must be synthesized in sufficient purity. It is necessary to establish the international purity and assay criteria for synthetic angiotensins. In comparative studies on physiological aspects, the strategy is to establish the physiological roles of the RAS in vertebrate classes. Controls of blood pressure, of aldostrone secretion, of glomerular filtration rate and tubular transport, and of drinking and intestinal absorpiton are the candidates. Physiological roles of extrarenal renin as well as renal one are interesting. A renin-like substance in the corpuscles of Stannius in the teleosts has been identified preliminarily as hypocalcin. Many frontiers exist in these fields, and one can expect fruitful contributions to research of the cardiovascular disease in humans through comparative studies of the RAS.

Amino Acid Sequence↗
PubMed1978

Costs of gastrointestinal examinations: a comparative study.

The costs of performing four major gastrointestinal examinations were studied and compared: single-contrast and double-contrast upper gastrointestinal series, and single-contrast and double contrast barium enema. A total of 1,725 examination records were reviewed for the number of films expended, room occupancy time, and physician involvement time, and the costs of the studies determined. The data indicated a large and significantly increased time and expense required for the double-contrast barium enema over the single-contrast barium enema. A relatively small increment was found in the cost performing the double-contrast upper gastrointestinal series over the single-contrast study.

Barium Sulfate↗
PubMed1979

Characterization of the molecular components in kinetoplast-mitochondrial DNA of Trypanosoma equiperdum. Comparative study of the dyskinetoplastic and wild strains.

The structure of the kinetoplast DNA of Trypanosoma equiperdum has been studied and compared to the structure of the circular mitochondrial DNA extracted from a dyskinetoplastic strain of T. equiperdum. In T. equiperdum wild type, the kinetoplast DNA constitutes approximately 6% of the total cellular DNA and is composed of approximately 3,000 supercoiled minicircles of 6.4 x 10(5) daltons and approximately 50 circular supercoiled molecules of 15.4 x 10(6) daltons topologically interlocked; The buoyant density in CsCl of the minicircles is 1.691 g/cm 3. The large circles have a buoyant density of 1.684 g/cm 3, are homogeneous in size and are selectively cleaved by several restriction endonucleases which do not cleave the minicircles. The cleavage sites of six different restriction endonucleases have been mapped on the large circle. The minicircles are cleaved by two other restriction endonucleases, and their cleavage sites have been mapped. The mitochondrial DNA extracted from the dyskinetoplastic strain of T. equiperdum represents 7% of the total DNA of the cell and is composed of supercoiled circles, heterogeneous in size, and topologically associated in catenated oligomers. Its buoyant density in CsCl is 1.688 g/cm 3. These molecules are not cleaved by any of the eight restriction endonucleases tested. The reassociation kinetics of in vitro labeled kDNA minicircles and large circles has been studied. The results indicate that the minicircles as well as the large circles are homogeneous in sequence and that the circular DNA of the dyskinetoplastic strain has no sequence in common with the kDNA of the wild strain.

Animals↗
PubMed2026

Robotic-assisted transbronchial biopsy versus computed tomography-guided transthoracic needle biopsy for peripheral pulmonary lesions: a systematic review and meta-analysis of direct comparative studies.

Robotic-assisted bronchoscopy (RAB) and computed tomography-guided transthoracic biopsy (CTTB) are competing strategies for sampling peripheral pulmonary lesions (PPLs). Whether they differ in yield or safety is uncertain. To our knowledge, this is the first systematic review restricted to direct comparisons. We searched MEDLINE, Europe PMC, Scopus, Web of Science and ClinicalTrials.gov from inception to 7 July 2026 for studies directly comparing RAB with CTTB in adults with PPLs. The primary outcome was strict 2024 American Thoracic Society/American College of Chest Physicians diagnostic yield. Risk of bias was assessed with ROBINS-I and certainty with GRADE. A cohort-genealogy step identified, per outcome, the largest set of cohorts sharing no patients; only that set was pooled, with Hartung-Knapp and Mantel-Haenszel sensitivity analyses. Five retrospective studies from one US health system were eligible. Four share patients; at most three cohorts are mutually independent. Across those three, diagnostic yield was comparable (risk ratio [RR] 0.99, 95% confidence interval [CI] 0.93-1.06; I²=24%; Hartung-Knapp 0.87-1.13), with an identical relative effect under strict and intermediate definitions although absolute yields fell from 88% to 74-84% under strict criteria. Pneumothorax requiring a chest tube and/or admission was about three-quarters less frequent with RAB across all three cohorts (RR 0.25, 95% CI 0.14-0.46; I²=0%; Hartung-Knapp 0.07-0.96). Strict yield (RR 0.99) and any pneumothorax (RR 0.06) were reported by two cohorts each and neither survives the few-studies correction. RAB took about 50 min longer than CTTB where same-session staging endobronchial ultrasound was counted in the robotic time, but only about 8 min longer than CTTB where it was not. Only one cohort reported yield by lesion size category and none reported yield by bronchus sign or lung zone, so lesion-level subgroups could not be pooled. Certainty was low for pleural complications and very low elsewhere. Low-certainty evidence indicates that RAB is associated with fewer pleural complications, with no statistically detectable difference in diagnostic yield; equivalence was not formally established. Because all evidence is retrospective, confined to one health system, and almost never stratified by lesion size or accessibility, these findings are hypothesis-generating and require a multicenter randomized trial.

Humans↗
PubMed1979

Lymphocyte studies in rheumatoid arthritis. III. A comparative study of the responses of peripheral blood and synovial fluid lymphocytes to phytomitogens.

The response of peripheral blood and synovial fluid lymphocytes to three non-specific mitogens has been studied. The paired samples were taken from patients with a range of inflammatory arthritides. Unstimulated synovial fluid lymphocytes (SFL) tended to have a greater uptake of tritiated thymidine than had unstimulated peripheral blood lymphocytes (PBL). This background uptake of tritiated thymidine by SFL showed a positive correlation with the response these SFL then showed to the mitogens. A significant depression was observed in the SFL response to phytohaemagglutinin when compared with the paired PBL response; this was seen in both the rheumatoid arthritis and other inflammatory joint diseases groups. SFL responses to concanavalin A and pokeweed mitogen, although depressed in individual cases, failed to show a significant depression overall. Attempts to restore the SFL response to that of the paired PBL by removal of any possible blocking substance from the cell surface either by pre-incubation of SFL in tissue culture medium or by enzyme treatment were unsuccessful. This suggested that cell surface blockers were possibly not the reason for deficient SFL reponses and that other factors were involved.

Arthritis, Rheumatoid↗
PubMed1977

[On the efficiency of new antiinflammatory agents. A comparative study (author's transl)].

In a comparative study new antiinflammatory agents, like sodium-(3-[(2,6-dichlorephenyl)-amino5-phenyl)-acetate (diclofenac); d,l-2-(3-phen0xy-phenyl) propionic acid (fenoprofen); 2-(3-benzoxyl-phenly-propionic acid (ketoprofen); cis-5-fluoro-2-methyl-1-(p-methylsulfinyl) benzylideryl-3-indenyl-acetic acid (MK 231, sulindac); 2-(6-methoxy-2-naphthyl)-propionic acid (naproxen/, showed nearly the same antiiflammatory effectiveness as 5-methoxy-2-methyl-1-(4-chlorobenzoyl)-indolyl-(3)-acetic acid (indometacin). In homogenates of inflamed rat paws an antiproteolytic activity of the new antiinflammatory agents was lacking.

Animals↗
PubMed1979

[Experimental studies of various model materials. 1. Comparative study on linear dimension behavior].

The linear dimensional behaviour of the model materials Begolith, Dentaloc, Tewestone, Impredur and Keramik-Cement was investigated at various mixing temperature, the thickness of layer ranging from 3 to 5 mm. It seems that the model materials Begolith, Dentaloc and Tewestone will yield good results in practice. Impredur may be recommended on certain conditions. On the contrary, Keramik-Cement is not suited as a model material.

Dental Materials↗