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N Arber

Publications and source records attributed to N Arber.

At least 145 records · Page 8Linked to original sources
PubMed1991

Streaming kidney.

Twenty-five male young adult random bred rats, weighing 250-300 g, were injected with 18.5 kBq/g body weight tritiated thymidine (specific activity 185 GBq/mM). The rats were then killed in groups of five, at the following times: 1 h and 14, 30, 60 and 120 days. The kidneys were processed histologically and dipped into liquid emulsion, exposed for 3 weeks and developed. Kinetic measurements were restricted to juxta-medullary glomeruli, their adjacent convoluted tubules and medullary tubuli. All other nephrons were ignored. The medullary pole of the juxta-medullary glomerulus served as reference point for all measurements and was referred to as the origin. The distance of a labelled cell from the origin was measured with an eye-piece micrometer and expressed in terms of two units: distance (microns) and cell location, defined as the number of cells separating a labelled cell from origin. Since only medullary nephrons were considered, these measurements represent distances directed toward the papilla. One hour after labelling, most cells were in the vicinity of the juxta-medullary glomerulus, not further than 800 microns from the origin in the direction of the papilla. During the following days labelled cells advanced toward the papilla at a daily velocity of 13.8 microns, covering 1.1 locations/day. Kinetically, the juxta-medullary nephron is a two-compartment cell renewal system. Its compartments, the progenitor (P) and the functional (Q), cover locations 0-80 and 81-150, respectively. The first feeds the second with cells. Morphologically, the progenitor compartment includes proximal and distal convoluted epithelia and a part of thick straight tubules. Other nephron portions belong to the Q-compartment. It is assumed that the nephrocyte is a part of a cell stream directed toward the papilla, which probably also includes stroma and vasculature.

Animals↗
PubMed1991

Streaming liver. VIII: Cell production rates following partial hepatectomy.

Twenty-four young, female, random-bred rats weighing 250 g were partially hepatectomized and killed in groups of four animals at the following times: 1 h and 1, 2, 3, 7 and 14 days. One hour before killing, each rat was injected i.p. with 0.5 microCi [3H]-thymidine, specific activity 5 Ci/mmol/g body weight. Livers were processed histologically and dipped into liquid emulsion for autoradiography. Twenty-four hours after partial hepatectomy, hepatocyte and littoral labelling indices rose, reaching on the third day respective peak values of 3.7%, and 15.4%, whereupon they declined, remaining slightly above pre-treatment level. Labelling indices served for cell production estimates. On day 3 the hepatocyte labelling index rose 26-fold. At the same time hepatocytes doubled their ploidy, indicating that half of the observed L.I. increase was directed to DNA accumulation and not to cell division. The hepatocyte production rate therefore increased 13-fold (or 1300%). The acinus diameter increased 15%, and cell density declined 5%, so that the acinus capacity to retain cells increased only 5%. Since the acinus did not enlarge proportionally to cell production, it is concluded that 95% of newly formed cells were eliminated. Partial hepatectomy thus triggers two processes: an acute process lasting about a week marked by massive and rapid cell turnover during which most newly formed cells are eliminated; and a second, more protracted process which serves for liver mass restoration. It is proposed that partial hepatectomy induces an acute shortage of a hitherto unknown metabolite that is produced by newly formed cells immediately after hepatectomy.

Animals↗
PubMed1991

Close association of HLA-B51 and B52 in Israeli patients with Behçet's syndrome.

Epidemiological data, family history, clinical data, and HLA typing were studied in three groups of patients with Behçet's syndrome: six Israeli Ashkenazi Jews, 29 non-Ashkenazi Jews, and three Israeli Arabs. HLA-B51 and B52 were present in 24/38 (63%) and 8/38 (21%), respectively, of the patients compared with 13/151 (9%) of the control group for both cases, a relative risk of 18.2 and 2.8 respectively. The syndrome was found in six of the 34 families. Ninety five per cent of the affected family members were either B51 or B52 positive. Eleven of the 14 families (79%) chosen for study contained a close relative of the proband who had recurrent oral ulcers. All the relatives with ulcers, except for one, were B51 or B52 carriers. Recurrent oral ulcers in the patients with Behçet's syndrome began a few years before other manifestations of the syndrome occurred. Our findings suggest that (a) HLA-B51 and HLA-B52 are primarily associated with Behçet's disease of Israeli patients; (b) the familial occurrence of this syndrome is high and occurs predominantly in the B5 positive group; (c) recurrent oral ulcers may be the first symptom of Behçet's syndrome, appearing early in life; HLA analysis can provide the clue for a correct diagnosis; (d) ulcer recurrence is common among members of a family containing a patient with Behçet's syndrome.

Behcet Syndrome↗
PubMed1991

Detection of aggregated leukocytes in the circulating pool during stress-demargination is not necessarily a result of decreased leukocyte adhesiveness.

Leukocyte endothelial interactions are essential for a normal immune response. It is known that this response is influenced by stress and that the latter induces demargination. We examined the question of whether stress demargination results from a decreased state of leukocyte adhesiveness. Included were various volunteers and patients under different degrees of stress. 66 young athletes before beginning their daily exercises, 67 middle-aged healthy volunteers, 25 patients before ergometry for evaluation of chest pain, 75 patients who were referred to the emergency room with chest pain without ischemia/infarction, 78 patients with ischemia/infarction, 65 patients with minor trauma, 25 with a fracture and 12 with polytrauma. The leukocyte adhesiveness/aggregation (LAA) values were measured with a direct slide test. The respective LAA values were 7.4 +/- 4.7, 6.3 +/- 4.4, 5.8 +/- 3.6, 5.2 +/- 3.5, 10.8 +/- 8.5, 9.1 +/- 5.8, 12.2 +/- 6.6 and 19 +/- 12.6% of aggregated leukocytes. We conclude that an increase in aggregated white blood cells can be detected in the circulating pool during major stress. It is therefore suggested that stress demargination is not necessarily a result of diminished leukocyte adhesiveness.

Adolescent↗
PubMed1991

Possible role for a plasma factor in the induction and/or maintenance of the state of leukocyte adhesiveness/aggregation in the peripheral blood. A study of mothers and their newborns.

The adhesive property of white blood cells is essential for a normal immune response. We examined the state of leukocyte adhesiveness/aggregation (LAA) in the peripheral blood of 31 mothers and their newborns by means of a direct slide test and found it to differ significantly, the respective per cents of aggregated leukocytes found in the peripheral blood being 15 +/- 6.4 and 5 +/- 3.3 (mean +/- SD). However, the particle concentration of white blood cells in the peripheral blood did not differ significantly (14.2 +/- 4.4 and 13.6 +/- x 10(9) l-1). By incubating a mother's plasma with her newborn's whole blood we could induce a significant (p less than 0.0001) increment in the state of LAA. We conclude that deficiency of a plasma factor that does not cross the placenta is responsible for the low LAA in the newborn's peripheral blood.

Cell Adhesion↗
PubMed1991

Heterotypic leukocyte aggregation in the peripheral blood of patients with leukemia, inflammation and stress.

This study deals with the question of whether the aggregates of leukocytes in the peripheral blood are homo- or heterotypic. One hundred-fifty individuals with leukemia, inflammation, and physical and mental stress, were examined. It was found that the various cell populations of the peripheral blood are represented in the aggregates and that aggregates are generally heterotypic. Normal and malignant leukocytes were noted in aggregates of patients with leukemia, suggesting that adhesive mechanisms are similar for both normal and malignant leukocytes. This was also supported in two animal models, one with leukocytosis of normal cells and the other with leukocytosis of leukemic cells, in which the state of leukocyte adhesiveness/aggregation in the peripheral blood correlated with tissue leukostasis. The possibility exists that "non specific stickers", present in the peripheral blood, promote interactions between the white blood cells, normal and malignant, and between these cells and the endothelium.

Adolescent↗
PubMed1991

Native valve Staphylococcus epidermidis endocarditis: report of seven cases and review of the literature.

This report describes seven patients from three university hospitals whose native valve infective endocarditis was caused by Staphylococcus epidermidis. The literature on endocarditis caused by S. epidermidis is also reviewed and the clinical features of patients with native valve endocarditis due to this organism are compared with those of patients from a general series of infective endocarditis cases. Compared with infective endocarditis caused by other organisms, S. epidermidis endocarditis tends to occur more frequently in male patients. Patients with S. epidermidis endocarditis exhibit fewer embolic complications and skin manifestations. The frequency of congestive heart failure is lower in this group. The relative indolent course and apparent rarity of native valve S. epidermidis endocarditis necessitate a high index of suspicion for early diagnosis.

Aged↗
PubMed1990

Streaming liver. VI: Streaming intra-hepatic bile ducts.

Thirty male adult rats, weighing 250-300 g, were injected with 0.5 muCi [3H]-thymidine. The rats were killed in groups of five, at the following times: 1 h, 14, 30, 60, 90 and 120 days. The livers were fixed in formalin, embedded in paraffin and cut into 5-microns-thick sections, which were then dipped into liquid emulsion for autoradiography. Bile ducts were evaluated in all portal tracts of a section. Obliquely cut bile ducts were excluded. The number of cells paving the duct lumen was defined as bile duct class. Class is roughly proportional to bile duct size. One hour after labelling, labelling index was 3.39 +/- 0.06% (the second number is one standard error of the mean). With time it declined, reaching 0.22 +/- 0.15 on day 60. Initially labelled cells were found in narrow bile ducts and the mean labelled cell was located at class 7.48 +/- 0.63. With time, labelled cells proceeded into wider bile ducts advancing daily 0.122 +/- 0.025 classes. Intra-hepatic bile duct epithelium renews its cells continuously in the same way as epidermis or gastro-intestinal mucosa do. It consists of two kinetic compartments, a progenitor (P) and a functional (Q) compartment. P feeds Q with cells.

Animals↗
PubMed1990

Streaming pancreas: islet cell kinetics.

Thirty male young adult rats aged 7 weeks, weighing 200 g, were injected with 0.5 microCi/g body weight tritiated thymidine (specific activity 5.0 Ci/mM). The rats were then killed in groups of five, at the following times: 1 hour, and 14, 28, 42, 56, 90, and 120 days. The pancreata were dissected, embedded in paraffin, and cut into 5 microns thick sections which were then dipped into liquid emulsion. The labelling index of acini and islet cells was estimated in each autoradiogram, and their distance from intercalated duct was measured. Acini and islet cells streamed away from the intercalated duct at a daily velocity of 0.52 microns. Acinus labelling index which was initially 0.78% declined with time. Islet cell labelling index was initially 0.38%. In the following days it climbed upward reaching on the 42nd day its peak value of 0.78%. From then onward it declined to a low of 0.38%. Since cells were labelled only once, and labelling was instantaneous, it is concluded that labelled acinus cells entered the islet, and that acinus cells are actually islet cell precursors. The pancreas is structured kinetically like other exocrine glands, being a two compartment cell renewal system which continuously renews its cells. The pancreocyte is a descendant of an intercalated duct progenitor. After leaving the duct it turns into an acinus cell, gradually approaching the Langerhans islet. After crossing its border it becomes an islet cell, and proceeds toward the islet center. Its population size dwindles exponentially until at islet center all cells are eliminated.

Animals↗
PubMed1990

[Leukergy 1990].

Explore the source record for details and available documents.

Animals↗
PubMed1989

Adult onset Still's disease.

Three patients with adult onset of Still's disease are presented. Common early findings were: septic fever, polyarthralgia, leukocytosis, neutrophilia and elevated sedimentation rate. All of them had abnormal liver function tests which returned to normal values following corticosteroid therapy. It is proposed that hepatic abnormalities in adult onset of Still's disease reflect the basic disease process.

Adult↗
PubMed1989

The streaming of the submandibular gland. II: Parenchyma and stroma advance at the same velocity.

Thirty young male rats aged 7 weeks, weighing 200 g, were injected with 18.5 kBq g-1 (0.5 microCi g-1) body weight tritiated thymidine [3H]TdR (specific activity 185 GBq). The rats were then killed in groups of five, at the following times: 1 hour, and 14, 30, 60, 90, and 120 days. Autoradiograms of sections through the submandibular gland were prepared, and the location of labelled cells in tubular and acinar cross sections was recorded. The nuclear content of each cross section was defined as its 'class'. In this numbering system, narrow tubuli, e.g. intercalated ducts are of low class, and wider tubuli, e.g. striated ducts, of high class. One hour after labelling most labelled tubular cells were found in low class cross sections, i.e. intercalated ducts and narrow granular ducts. Striated ducts were not labelled. From then onward labelled cells entered wider tubuli, e.g. striated ducts. The advancing labelled epithelium was accompanied by labelled stroma. Both cell types traversed 0.089 classes per day. In acini, labelled cells advanced in the opposite direction, starting from acinar cross sections of high class and ending in class-1 cross sections.

Animals↗
PubMed1989

[Infection with Mycobacterium avium complex in the nonimmunocompromised host].

Pulmonary infection due to mycobacterium avium complex has been considered exceedingly rare, with only 50 case reports in the literature until 1982. However, during the past decade the dissemination of the acquired immune deficiency syndrome has been accompanied by a marked increase in the frequency of reported infections due to this agent, although infection in the noncompromised host remains rare. We describe an 80-year-old man who was not immunocompromised but who was infected with mycobacterium avium complex.

Aged↗