Histological studies of surgically resected hepatocellular carcinoma following combined radiotherapy and hyperthermia

Four cases of hepatocellular carcinoma (HCC) were surgically resected following combined radiotherapy (RT) and hyperthermia (HT). Complete necrosis of the tumor without viable tumor cell was found in one case and extensive tumor necrosis was observed in the other three cases; the percentage of necrosis in the specimens were 40%, 70%, and 80%, respectively. Histologic assessment showed mainly coagulative necrosis in the tumor with focal liquefactive necrosis. Cystic dilatation of sinusoids was observed in both tumor and nontumorous normal liver tissue. Other changes in normal liver tissue were unremarkable except for infiltration of inflammatory cells, fatty change, and proliferation of the bile ducts which can usually be seen beyond the area where any space occupying lesions are present. It is concluded that combined radiotherapy and hyperthermia can significantly induce coagulative necrosis of hepatocellular carcinoma with nonsignificant minimal histologic changes in adjacent nontumorous liver tissue.

The incidence of recurrent soft tissue ankle injuries

A prospective study was carried out to assess the incidence of recurrent soft tissue injuries to the ankle joint. Out of 310 patients with acute ankle injuries seen in the accident and emergency department at the Royal Victoria Infirmary, Newcastle upon Tyne, 101 (32.5%) had injuries which were severe enough to necessitate review in the follow-up clinic. Twenty-seven of these patients (26.7%) had sustained one or more previous injuries to the same ankle within the past 24 months. This rather high incidence of recurrence highlights the need to evaluate our current diagnostic and treatment policies in dealing with this common injury.

Differential responses persist in shoot explants regenerated from callus of two mature black locust trees

Callus cultures were established from internodal segments of shoot cultures from two mature black locust Robinia pseudoacacia L. trees. Callus of both trees produced shoots on Murashige and Skoog (MS) medium supplemented with 10 microM 6-benzylaminopurine alone or in combination with 1 microM naphthaleneacetic acid. Regenerated shoots were successfully multiplied on MS medium containing 0.32 microM 6-benzylaminopurine, and produced roots on 0.1 strength MS medium containing 1 microM indole-3-butyric acid. One clone consistently outperformed the other with respect to shoot proliferation and proportion of shoots that produced roots. This distinction had previously been observed in shoots produced from bud explants obtained from the mature trees.

Solution conformations of the B-loop fragments of human transforming growth factor alpha and epidermal growth factor by 1H nuclear magnetic resonance and restrained molecular dynamics

A restrained molecular dynamics simulation approach that explicitly includes the effect of the surrounding solvent molecules is applied to the NMR determination of the conformations of the B-loop fragments of human transforming growth factor alpha and epidermal growth factor. Backbone interproton distance restraints are obtained by using two-dimensional rotating frame nuclear Overhauser effect spectroscopy (ROESY). The simulations are carried out both in "vacuum" and in "water." The results are discussed in terms of the energetics, agreement with the NMR distances, and the flexibility of the peptides.

Endoscopic injection sclerotherapy in patients with bleeding esophageal varices: a retrospective analysis

Endoscopic injection sclerotherapy has been accepted as the procedure of choice for patients with variceal hemorrhage. To evaluate the efficiency of endoscopic injection sclerotherapy in patients with bleeding esophageal varices, we did a retrospective study of 52 patients (non-sclerotherapy group) with bleeding esophageal varices who were admitted to hospitals and did not receive sclerotherapy and of 50 patients (sclerotherapy group) who received sclerotherapy with ethanolamine oleate. The mortality (sclerotherapy group vs. non-sclerotherapy group: 18.0% vs. 32.7%) during index hospitalization, the bleeding risk factor (the number of rebleeds per patient/month; 1.56 +/- 2.76 vs. 4.96 +/- 9.99: mean +/- SEM) and the mortality due to bleeding (14.0% vs. 36.5%) were higher in the non-sclerotherapy group than in the sclerotherapy group. Only those in Child's class C who received sclerotherapy had a significantly better survival rate than the non-sclerotherapy group (p less than 0.05). Although formal comparisons were not made because of the retrospective nature of this study, endoscopic injection sclerotherapy is effective and appears to be superior to conventional medical treatments.

Management of partial skin thickness burn wounds with Inadine dressings

In a prospective randomized trial, 213 consecutive patients with less than 10 per cent BSA partial thickness burns were treated as outpatients with either Bactigras (n = 102) (tulle gras dressing with 0.5 per cent Chlorhexidine Acetate B.P.) or Inadine (n = 111) (rayon dressing with 10 per cent povidone iodine ointment). Inadine caused less bleeding on dressing removal but not significantly less. Inadine treated patients required less analgesia, a reduced treatment time, a smaller number of hospital visits and less time off work/normal activities (P = 0.01). Inadine should be more widely used in the management of partial thickness burn wounds.

Percutaneous fine needle aspiration biopsy of pancreatic cancer guided by ultrasonography

Fine needle aspiration biopsy guided by ultrasonography was performed in 39 patients with pancreatic cancer to evaluate the value of the technique for establishing a proved histologic diagnosis. Aspirated material suitable for cytologic evaluation of smear preparation was obtained from 33 patients (84.6%). Among the 33 patients, cytologic diagnosis of pancreatic cancer was possible in 28 patients (84.9%). There was mild abdominal pain only in one patient (2.6%). In conclusion, percutaneous fine needle aspiration biopsy guided by ultrasonography proved to be a safe and useful method for histologic diagnosis of pancreatic cancer.

Comparison of the conformation and GTP hydrolysing ability of N-terminal ras p21 protein segments

Conformational, GTP binding, and GTP hydrolytic studies are carried out with synthetically prepared N-terminal 34 residue segments (residues 2-35) of p21 ras oncogenic (12-Val) and non-oncogenic (12-Gly) proteins. It was found that these N-terminal regions bind nucleotides through their phosphate groups, and that substitution of valine for glycine produces a more pronounced alpha-helical structure and decreases the conformational flexibility. The glycine containing peptide, when compared to the valine containing analog, catalyses the hydrolysis of GTP 6 times more efficiently. Results suggest that restriction of conformational adaptation may contribute to the transforming capacity of the Val-12 p21 protein.

Proton magnetic resonance study of the influence of chemical modification, mutation, quaternary state, and ligation state on dynamic stability of the heme pocket in hemoglobin as reflected in the exchange of the proximal histidyl ring labile proton

Proton nuclear magnetic resonance spectroscopy has been utilized to investigate the rates of exchange with deuterium of the proximal histidyl ring protons in a series of chemically modified and mutated forms of Hb A. Differences in rates of exchange are related to differences in the stability of the deformed or partially unfolded intermediates from which exchange with bulk solvent takes place. Each modified/mutated Hb exhibited kinetic subunit heterogeneity in the reduced ferrous state, with the alpha subunit exhibiting faster exchange than the beta subunit. Modification or mutation resulted in significant increases in the His F8 ring NH exchange rates primarily for the affected subunit and only if the modification/mutation occurs at the allosterically important alpha 1 beta 2 subunit interface. Moreover, this enhancement in exchange rate is observed primarily in that quaternary state of the modified/mutated Hb in which the modified/substituted residue makes the intersubunit contact. This confirms the importance of allosteric constraints in determining the dynamic properties of the heme pocket. Using modified or mutated Hbs that can switch between the alternate quaternary states within a given ligation state or ligate within a given quaternary state, we show that the major portion of the enhanced exchange rate in R-state oxy Hb relative to T-state deoxy Hb originates from the quaternary switch rather than from ligation. However, solely ligation effects are not negligible. The exchange rates of the His F8 ring labile protons increase dramatically upon oxidizing the iron to the ferric state, and both the subunit kinetic heterogeneity and the allosteric sensitivity to the quaternary state are essentially abolished.(ABSTRACT TRUNCATED AT 250 WORDS)

Ankle swelling is not always 'medical'

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Conformational and receptor binding properties of human EGF and TGF-alpha second loop fragments

The solution conformation of the second loop fragment of human EGF, [Ala20] EGF (14-31), was determined using two-dimensional NMR homonuclear Hartmann-Hahn and rotating frame nuclear Overhauser enhancement spectroscopy. The results are compared with the conformation of the second loop fragment of human TGF-alpha, [Ala21] TGF-alpha(16-32), and with that of the second loop of intact EGF. Comparison of the two experimentally determined structures of the second loop fragments shows significant differences in the turn regions of each peptide. For the EGF fragment, hydrophobic side chain groups protrude away from the ring, whereas for the TGF-alpha fragment hydrophilic groups are directed away from the ring. Although these turn regions represent the putative receptor binding sites, neither second loop fragment binds to the EGF receptor. The biological activity is discussed in terms of the conformational differences found for the two second loop fragments.

Hydrogen bonding between cytosine and peptides of threonine or serine: is it relevant to the origin of the genetic code?

13C, 15N, and 1H nuclear magnetic resonance measurements indicate that chloroform-soluble threonine-containing tripeptide derivatives, such as t-Boc-Thr-Gly-Gly-OBz, form three strong hydrogen bonds to the cytosine moiety of 2',3'-O-isopropylidene-5'-O-t-butyldimethylsilylcytidine. The C = O and NH of the central peptide residue plus the OH of the threonine side chain appear to form bonds to the N(4')H2, N(3), and C(2) = O, respectively, of the pyrimidine. An association constant calculated from the cytidine 15N(4') nuclear magnetic resonance response to added peptide is four times larger than the corresponding cytosine-guanine constant. It is suggested that cytosine-peptide bonding was part of the primitive genetic coding mechanism early in evolution and accounts for the origin of the cytosine-centered codons for the hydroxy amino acids, serine and threonine, in the present code.

Nuclear magnetic resonance study of the isotope exchange of the proximal histidyl ring labile protons in hemoglobin A. The exchange rates and mechanisms of individual subunits in deoxy and oxy-hemoglobin

Proton nuclear magnetic resonance spectroscopy has been used to investigate the rates and mechanism of exchange with deuterium of the proximal histidyl imidazole labile ring proton in deoxy and oxy-hemoglobin A. The resolved signals for the two subunits indicate dynamic heterogeneity, with the exchange rate always faster in the alpha than the beta subunits, suggesting a lower dynamic stability for the alpha subunit. The activation energy for the exchange in both subunits (approximately 25 kcal; 1 cal = 4.184 J) indicates that exchange proceeds via an intermediate far from denaturation or global unfolding. The pH profiles for both hemoglobin states reflect the EX2 mechanism for both subunits. While the base catalysis expected for an iron-bound imidazole is observed in all cases, there are important differences in both rates and mechanisms between the subunits. In deoxy-hemoglobin, both base-catalyzed and water-assisted exchange contribute to the alpha subunit, but only the former to the beta subunit. For oxy-hemoglobin, the base-catalysis is retained for both subunits, but the slope is considerably less for the alpha relative to the beta subunit. Thus the two subunits in the two states of hemoglobin differ both in mechanisms and in the inherent dynamic stability reflected in any one mechanism. The relationships of the proximal histidyl ring NH exchange rates to previously characterized subsets of allosterically responsive protons in hemoglobin A is briefly discussed.

Use of autogenous split-thickness dermal graft for reconstruction of the lining of the exenterated orbit

A surgical technique using an exposed dermal graft to line the exenterated orbit has been successful in nine patients. Eight of the nine patients had undergone total maxillectomy at the time of exenteration. A split-thickness (epidermal) skin graft is harvested with a dermatome and hinged at one end. A second split-thickness dermal graft is harvested from the dermal bed of the first graft. The hinged epidermal graft is sutured into its donor site, and the deeper free dermal graft is used to line the orbital cavity. The latter graft tends to be more viable than a split-thickness epidermal graft. Also, because the dermal graft can self-epithelialize or be epithelialized by adjacent tissues, it may be placed adjacent to skin or a mucous membrane.