Nontransferrin-bound serum iron in thalassemia and sickle cell patients

Nontransferrin-bound iron (NTBI) was separated from transferrin bound iron (TBI) by DEAE-Sephadex-CDS filtration. TBI is eluted with Tris-NaCl buffer, NTBI that is retained on the column is eluted with citric acid. NTBI was identified in serum from thalassemia and sickle cell patients. Normal serum contained less than 6% NTBI as compared with 15-18% in patient's sera. NTBI levels were decreased significantly after 8 hr chelation with deferoxamine (DFO).

One-stage reconstruction of esophageal defect by free transfer of jejunum: treatment and complications

We report on 20 patients with esophageal defects that were reconstructed by jejunum transplant with the help of microsurgical techniques. Sixteen attempts were successful, for a success rate of 80%. Three types of reconstruction were used: free jejunum transfer, free jejunum flap transfer, and partially pedicled jejunum transfer with the distal portion revascularized. This article emphasizes the complications of these procedures, including tearing of the jejunum mesentery, thrombosis at the anastomotic stoma, balloon-like distention of the cervical portion of the transferred jejunum, strangulation at the diaphragm foramen, and stenosis of the anastomotic stoma between the remnant of the esophagus and the transferred jejunum. Measures for prevention and treatment of these complications are also discussed.

A case-control study of trophoblastic diseases in the People's Republic of China

A case-control study is currently under way in Beijing, People's Republic of China, involving approximately 165 patients with invasive moles or choriocarcinoma, 165 with hydatidiform moles, and 330 population controls, who were matched to the patients with invasive moles or choriocarcinoma on age and interval since last pregnancy. The interviews are focused on a number of suspected risk factors, including previous pregnancy outcomes, history of hydatidiform mole, medical factors, drug usage, family history, and diet. A brief background of the study and methods as established through a previous pilot study are given.

Vascular metatarsophalangeal to ankylosed temporomandibular joint replacement

Four cases of unilateral temporomandibular (TM) joint ankylosis were successfully treated by metatarsophalangeal to TM joint replacement by microvascular technique. Results 6 to 20 months postoperatively were encouraging. Further follow-up studies are necessary to evaluate the long-term results.

Lymphocyte phenotype and function in chronically transfused children with sickle cell disease

Immunologic studies were performed on mononuclear cells from ten chronically transfused children with sickle cell disease, and the results were compared with those from five other groups: 21 sickle cell patients who were not receiving regular transfusions, 6 chronically transfused children with other forms of refractory anemia, 10 previously splenectomized children, 5 boys with hemophilia A, and 27 normal adult controls. The helper:suppressor T cell ratios (T4:T8) in all groups except hemophiliacs were normal, were unrelated to the number of units transfused, and were not suggestive of findings reported for patients with the acquired immune deficiency syndrome (AIDS) or groups at risk for the syndrome. Percentages of T3, T4, and T8 cells were low in sickle cell and splenectomized patients, but not in chronically transfused patients with other anemias. Serum IgG was frequently elevated, and IgG synthesis in vitro was increased relative to IgM synthesis in sickle cell patients. Coculture experiments indicated that such findings may stem from a selective increase in IgG synthesis by B cells. Thus, transfused sickle cell patients have a particular pattern of immunologic abnormalities that is distinct from that seen in AIDS.

Ouabain decreases apparent potassium-conductance in proximal tubules of the amphibian kidney

According to a previous study from this laboratory, the electrochemical gradient for potassium across the peritubular cell membrane of proximal tubules in the isolated perfused frog kidney increases following the application of ouabain. In order to test, if this phenomenon were due to a decrease of potassium conductance, the effects of ouabain on cell membrane resistances and the sensitivity of the peritubular cell membrane potential difference (PDpt) to step changes of peritubular potassium and bicarbonate concentration were studied. In the absence of ouabain, PDpt averaged -60 +/- 3 mV (n = 25). A step increase of peritubular potassium concentration from 3 to 18 mmol/l (pH 8.07) depolarizes PDpt (delta PDk) by +24 +/- mV (n = 8). An increase of bicarbonate from 20 to 40 mmol/l (pH 8.07) hyperpolarizes PDpt (delta PDb) by -2.8 +/- 0.4 mV (n = 9). The resistance of the luminal and peritubular cell membranes in parallel (Rm) amounts to 45 +/- 9 k omega cm (tubule length) (n = 4) and the voltage divider ratio (VDR) to 1.4 +/- 0.2 (n = 7). The resistance of the cellular cable (cellular core, Rc) approaches 131 +/- 37 M omega/cm (n = 4). Peritubular application of 0.1 mmol/l ouabain leads to a gradual decline of PDpt (t1/2 approx. 30 min), to an increase of Rm, a decrease of delta PDk and an increase of delta PDb. VDR and Rc are not changed significantly. The data point to a functional link between the sodium/potassium ATPase and the potassium conductance of the peritubular cell membrane.

Hemothorax and hemomediastinum in patients with hemophilia

Three patients with hemophilia presented with hemothoraces which resolved within 1-3 weeks following treatment with factor concentrates. Drainage of blood was not necessary. Eight previously reported cases are reviewed, and therapy and complications are summarized. We suggest that treatment of this rare complication of hemophilia with factor concentrates and avoidance of surgical intervention is indicated.

Mechanism of hydrogen ion transport in the diluting segment of frog kidney

Transepithelial H+ transport was studied in diluting segments of the isolated-perfused kidney of rana esculenta. The experiments were performed in controls as well as in K+-adapted and Na+-adapted animals (exposed to 50 mmol/l KCl or NaCl, resp. for at least 3 days). Conventional and single-barreled, liquid ion-exchanger H+-sensitive microelectrodes were applied in the tubule lumen to evaluate transepithelial H+ net flux (JHte) as well as limiting transepithelial electrical and H+ electrochemical potential differences (PDte, EHte) and luminal pH at zero net flux conditions. The measurements were made in absence (control) and presence of furosemide (5 X 10(-5) mol/l) or amiloride (10(-3) mol/l). EHte (lumen positive vs ground) was 19 +/- 3 mV in controls, 43 +/- 3 mV in K+ adapted but about zero in Na+ adapted animals. Using the corresponding PDte-values, steady state luminal pH of 7.63 +/- 0.05, 7.13 +/- 0.05 and 8.02 +/- 0.02 was calculated for the respective groups of animals (peritubular pH 7.80). In parallel, significant secretory JHte (from blood to lumen) was found in controls (14 +/- 2 pmol X cm-2 X s-1) which was stimulated by K+ adaptation (61 +/- 8 pmol X cm-2 X s-1) but reversed in direction by Na+-adaptation (-8 +/- 1 pmol X cm-2 X s-1). Amiloride inhibited secretory JHte.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of intracellular sodium activity on the transport of glucose in proximal tubule of frog kidney

Inhibition of basolateral Na+/K+ ATPase by ouabain eventually abolishes transport of glucose. The present study was performed to test, if this effect is due to a dissipation of the electrochemical gradient for sodium or due to a regulatory inhibition of sodium-coupled glucose entry across the luminal membrane at increasing intracellular sodium activity. To this end, proximal convoluted tubules of the doubly perfused isolated frog kidney were perfused alternatively with solutions containing either 5 mmol/l glucose or raffinose. The potential difference across the peritubular cell membrane (PDpt) and across the epithelium (PDte) has been recorded with conventional and across the peritubular cell membrane with ion selective microelectrodes (PDpt). In the absence of luminal glucose PDpt is (+/- SEM) -54.0 +/- 2.4 mV, PDte = -1.2 +/- 2.0 mV and PDNapt = -96 +/- 5 mV. The electrochemical gradient for sodium (mu Na+) amounts to 95 mV and intracellular sodium activity to 14 mmol/l (extracellular sodium activity is 74 mmol/l). Luminal application of glucose leads to a rapid depolarisation of PDpt (delta PDpt = 8.6 +/- 0.9 mV and PDNapt (delta PDNapt = 11.1 +/- 3.0 mV) and to hyperpolarisation of PDte (delta PDte = -0.8 +/- 0.2 mV). The peritubular application of ouabain leads to a gradual, reversible and proportional decline of PDpt, PDNapt and mu Na+. Glucose induced delta PDpt and delta PDNapt decrease in parallel to PDpt and PDNapt, resp. In a separate series, the lumped conductance (Gm) of the luminal and basolateral cell membrane has been determined, which amounts to 2.4 +/- 0.3 microS/mm (tubule length). Gm decreases 23 +/- 4%, when PDpt is decreased to half.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of ouabain on intracellular activities of K+, Na+, Cl-, H+ and Ca2+ in proximal tubules of frog kidneys

Using conventional and ion selective microelectrodes, the effect of ouabain (10(-4) mol/l) on peritubular cell membrane potential (PDpt), on intracellular pH (pHi) as well as on the intracellular ion activities of Cl- (Cli-), K+ (Ki+), Na+ (Nai+) and Ca2+ (Ca2i+) was studied in proximal tubules of the isolated perfused frog kidney. In the absence of ouabain (PDpt = -57.0 +/- 1.9 mV), the electrochemical potential difference of chloride (apparent mu Cl- = -22 +/- 2 mV) and of potassium (mu K+ = +24 +/- 3 mV) is directed from cell to bath, of H+ (mu H+ = -42 +/- 5 mV), of Na+ (mu Na+ = -102 +/- 4 mV) and of Ca2+ (mu Ca2+ = -148 +/- 6 mV) from bath to cell. Ouabain leads to a gradual decline of PDpt, which is reduced to half (PDpt, 1/2) within 31 +/- 4.6 min (in presence of luminal glucose and phenylalanine), and to a decline of the absolute values of apparent mu Cl+, of mu H+, mu Na+ and mu Ca2+. In contrast, an increase of mu K+ is observed. At PDpt, 1/2 apparent Cl-i increases by 6.2 +/- 1.0 mmol/l, pHi by 0.13 +/- 0.03, Ca2+i by 185 +/- 21 nmol/l, and Nai+ by 34.2 +/- 4.6 mmol/l, whereas Ki+ decreases by 37.7 +/- 2.2 mmol/l. The results suggest that the application of ouabain is followed by a decrease of peritubular cell membrane permeability to K+, by an accumulation of Ca2+, Na+ and HCO3- in the cell and by a dissipation of the electrochemical Cl- gradient.

Induction of chromosome aberrations and specific locus mutation but not sister chromatid exchanges in Chinese hamster ovary cells by neocarzinostatin

The induction of chromosome aberrations, sister chromatid exchanges (SCE), cytotoxicity, and 6-thioguanine-resistant mutation by neocarzinostatin (NCS) in Chinese hamster ovary cells was analyzed. It was observed that within the same concentration range of 0.01-0.1 mu/ml NCS, the drug induced a significant increase in all analyzed end-points except in SCE frequencies. There was no increase in SCE frequencies even when the cells were treated at the G1/S border in the first cell cycle and when aberrations were observed in the same cell showing a second cycle differential staining pattern. Our study indicates that the cellular damage induced by NCS leads to expression in chromosome aberrations, cytotoxicity, and mutagenicity but not in sister chromatid exchanges.

Immunoregulatory abnormalities in Evans syndrome

Immune function in six patients with Evans syndrome (Coombs-positive hemolytic anemia and immune thrombocytopenia) was compared to that in seven with chronic ITP. The two groups differed in measurements of T-cell subsets and immunoglobulin production. Evans syndrome patients had decreased T4 (T-helper) (P = 0.025), increased T8 (T-suppressor) (P = 0.008), and a decreased ratio of T4:T8 cells (P = 0.0009) when compared to controls. Results in chronic ITP patients were similar to those in controls. Serum IgG, IgM, and IgA levels and in vitro synthesis of IgG and/or IgM were decreased in most Evans syndrome patients. Diminished in vivo and in vitro immunoglobulin synthesis in Evans syndrome is consistent with the decreased T4:T8 ratio in these patients. The altered T4:T8 ratio may represent an unsuccessful response to an autoimmune process in which the trigger is unknown.

Keys to successful second toe-to-hand transfer: a review of 30 cases

Thirty cases of second toe-to-hand transfers are reported in which there were no failures. Factors judged to be important in these successful results include the careful choice of the donor site, distal to proximal exposure of first metatarsal artery, ensuring adequate perfusion of the toe before severing its vessels, and meticulous postoperative care.

Evidence for an amiloride sensitive Na+ pathway in the amphibian diluting segment induced by K+ adaptation

The effect of amiloride on cell membrane potentials and intracellular Na activity (Nai) was tested in early distal tubules of the isolated perfused kidney of control and of K-adapted (high-K diet) Amphiuma. Conventional and Na-sensitive liquid ion-exchanger microelectrodes were employed to measure the peritubular cell membrane potential (PDpt), the transepithelial potential difference (PDte) and the Na electrochemical gradient across the peritubular cell membrane (ENapt), in the absence and the presence of amiloride (1 X 10(-4) mol X 1(-1] in both groups of animals. Amiloride did not affect PDpt and ENapt in control animals but depolarized PDpt and ENapt by about 8 mV in K-adapted animals. Nai (11.0 +/- 0.6 mmol X 1(-1) in early distal cells of control animals) did not change significantly by this maneuver. However, Nai decreased to extremely low values (2.3 +/- 0.2 mmol X 1(-1] when the luminal cotransport system for Na, Cl and K was inhibited by the luminal application of furosemide (5 X 10(-5) mol/l) and when the luminal cell membrane was exposed simultaneously to amiloride. The amiloride-induced effects on PDpt, ENapt and Nai occurred within seconds and were fully reversible. We conclude that high-K diet (K adaptation) induces an amiloride-sensitive pathway in the luminal cell membrane of early distal cells of Amphiuma which exists in parallel with the furosemide-sensitive cotransport system located in this cell barrier. The results suggest a luminal amiloride-sensitive Na/H exchange mechanism which regulates the luminal K permeability.

Interaction of intracellular electrolytes and tubular transport

To disclose possible regulatory mechanisms, the potential difference across the peritubular cell membrane (PDpt) and intracellular activities of sodium (Nai+), potassium (Ki+), calcium (Cai2+), bicarbonate (HCO3i-) and chloride (Cli-) have been traced continuously during inhibition of Na+/K+-ATPase with ouabain. Within 31 +/- 4 min following application of ouabain, PDpt decreases (from 57 +/- 2 mV) to half and Ki+ by 37.7 +/- 2.2 mmol/l (from 63.5 +/- 1.9 mmol/l), Nai+ increases by 35.1 +/- 4.1 mmol/l (from 13.2 +/- 2.4 mmol/l), Cai2+ by 0.17 +/- 0.2 mumol/l (from 0.09 mumol/l), HCO3i-) by 3.0 +/- 1.1 mmol/l (from 15.3 +/- 2.0 mmol/l) and Cli- by 6.2 +/- 1.0 mmol/l (from 14.4 +/- 1.6 mmol/l). Within the same time the luminal and peritubular cell membrane resistances increase 45 +/- 15% and 53 +/- 17%, respectively. The increase of the resistances is mainly due to a decrease of K+ conductance, which in turn mainly accounts for the depolarisation of PDpt. Additional experiments demonstrate that the K+ conductance of the peritubular cell membrane is sensitive to the cell membrane potential difference and possibly linked to Na+/K+-ATPase activity. The decline of PDpt probably accounts for intracellular alkalinisation which in turn reduces Na+/H+ exchange. Na+-coupled transport of glucose and phenylalanine decrease in linear proportion to PDpt. The transport of these and probably of similar substances represents the main threat to electrolyte homeostasis of the cells.