A new device to stabilize templates for transperineal I-125 implants

Transperineal Iodine-125 implants of the prostate are currently being performed at Memorial Sloan-Kettering Cancer Center with CT-based treatment planning and transrectal ultrasound for verification of proper needle placement in the prostate at the time of implantation. An adjustable device, the WIPI, has been designed to stabilize the perineal template and rectal obturator during planning and implementation of the procedure. The device is simple to use and is compatible with CT scanning, transrectal ultrasound, and the Mick applicator. Its design and key functional features are described here.

[Integrated mother-baby nursing care]

The article describes how the obstetrical department at Notre-Dame Hospital in Montreal developed a new, integrated approach to maternal-infant care. The first part deals with the family-centred philosophy of the unit, which has had a profound influence on the nursing staff. It explains how the previous system of post-partum care was changed, what physical modifications had to be made in the obstetrical wing and the organizational changes required to make the new system work. The second part of the article deals with the results of all these changes, as perceived by the clients. A study was conducted, using an experimental and a control group. The former consisted of clients who had experienced the new integrated system of mother-infant care. Results showed them to be more satisfied with the care they received than the control group, who received care along the lines of the traditional model. Clients in both groups were equally satisfied with the physical changes in the obstetrical wing. In summary, the new approach seems to respond to the need expressed by many couples to have their baby in a family-style atmosphere.

Inflammatory cells in graft-versus-host disease on the rectum: immunopathologic analysis

The inflammatory infiltrate of acute rectal graft-versus-host disease (GVHD) was investigated by indirect immunofluorescence. Twenty biopsies from 11 allogeneic bone marrow transplant recipients were studied in four groups: biopsies before transplantation; biopsies after transplantation without GVHD; biopsies from patients with extra-intestinal GVHD only; and biopsies from patients with intestinal GVHD. Total T cell numbers (CD2+, CD3+) in the lamina propria differed little in the four groups. CD4+ lymphocytes appeared to be decreased in GVHD while CD8+ lymphocytes were significantly increased (p less than 0.01), thus significantly lowering the CD4/CD8 ratio. In pre-transplant patients and in those without GVHD this ratio resembled that in normal peripheral blood (1.44 +/- 0.5 and 2.46 +/- 1.3, respectively) but was significantly lower in both extraintestinal (0.71 +/- 0.08) and intestinal GVHD (0.56 +/- 0.08) (p less than 0.05). Acute intestinal GVHD was marked by a fourfold increase in CD57+ lymphoid cells within the epithelium and the lamina propria (p less than 0.05). The recognition of CD57+ cells, which may include natural killer-like cells, within rectal lymphoid infiltrates suggests a possible role for non-HLA restricted effector cells in GVHD of the rectum.

Simultaneous upper and lower endoscopic biopsy in the diagnosis of intestinal graft-versus-host disease

Graft-versus-host disease in the upper gastrointestinal tract presents with anorexia, vomiting, and abdominal discomfort. Because these symptoms are not specific, we have proposed that a diagnosis of upper GI GVHD requires histologic confirmation. However, the utility of upper endoscopy in the diagnosis of upper GI GVHD has not been examined. We report a retrospective analysis of 77 allogeneic bone marrow transplantation recipients who received simultaneous upper and lower GI tract biopsies. Upper GI GVHD was found in 44% of patients, of whom 59% also had a positive lower GI tract biopsy (P less than 0.001). Thirty-five percent of the patients with no clinical evidence of lower GI tract GVHD had symptomatic upper GI GVHD confirmed histologically. Patients with and without upper GI GVHD had no significant difference in their clinical symptoms or in their endoscopic findings. We found an association between upper GI and skin GVHD greater than stage I (P = 0.05), a trend to concordance between upper GI GVHD and clinical GVHD in the lower GI tract (P = 0.08), and with the overall clinical GVHD grade (P = 0.08) but no association with clinical liver involvement. Of these 77 patients, 16% had their treatment for acute GVHD changed to include systemic immunosuppression as a result of the upper GI endoscopic biopsy. In addition, 71% had other enteric pathology identified that required specific therapy. These data suggest that upper GI GVHD cannot be diagnosed accurately from its clinical presentation nor inferred from lower GI symptoms or from extraintestinal GVHD. Upper GI endoscopy with biopsy is an important tool in the diagnosis of intestinal GVHD.

Ornithine Decarboxylase Exhibits Negative Thermal Modulation in the Sea Star Asterias vulgaris: Potential Regulatory Role During Temperature-Dependent Testicular Growth

The common northern sea star Asterias vulgaris is exposed to seasonal variation in temperature from -2 to 17°C. A. vulgaris exhibits an annual reproductive cycle, i.e., the testes increase slowly in size during fall and winter, and reach maximal size in early spring. Slow testicular growth in the winter has been attributed to low field temperatures. Previous studies indicate that the specific activity of ornithine decarboxylase and the levels of the polyamines putrescine, spermidine, and spermine decrease in mid-winter and increase in the spring, coincident with changes in field temperatures. Kinetic studies show that ornithine decarboxylase assayed from individuals collected in March exhibits negative thermal modulation (Km of ornithine is 0.22 mM and 0.65 mM at 15 and 0°C, respectively). Q10 values are highest at low substrate concentrations and at low temperatures. We hypothesize that during the cold winter months a decrease in the amount of ODC and an increase in the apparent Km causes polyamine synthesis to decline, leading to decreased growth and development of the testis. We suggest that thermal modulation of ODC (and polyamine synthesis) is a mechanism by which seasonal temperature fluctuations influence seasonal spermatogenesis in A. vulgaris. We further suggest that growth of various tissues in many other ectothermal invertebrates may be similarly controlled.

Histamine H3 receptor binding sites in rat brain membranes: modulations by guanine nucleotides and divalent cations

The binding of [3H](R)alpha-methylhistamine, a potent and specific agonist at histamine H3 receptors, was investigated with membranes of rat cerebral cortex. In phosphate buffer the specific binding defined with thioperamide, an H3 receptor antagonist, displayed characters of reversibility and saturability with a Bmax of approximately 30 fmol/mg protein. The KD, derived from either dissociation/association rates or saturation kinetics at equilibrium, was approximately 0.5 nM at 25 degrees C. Competition studies indicated that the binding occurred with a stereoselectivity and pharmacological specificity similar to that of functional H3 autoreceptors regulating histamine release in brain slices. However, whereas the potency of antagonists was closely similar in the two assay systems, that of agonists was approximately 10-fold higher in the binding assay. Among antagonists burimamide was the only one to compete with a pseudo-Hill coefficient significantly different from unity (nH = 0.48 +/- 0.03), indicating a possible heterogeneity among binding sites. The presence of 2.6 mM Ca2+, in a modified Krebs-Ringer medium, promoted the conversion of a larger fraction of sites into a low-affinity component with a KD of 16 nM. The presence of guanylnucleotides in the Krebs-Ringer medium with Ca2+ abolished the binding to this low-affinity component whereas in a phosphate buffer only the KD was slightly increased. It is concluded that the H3 receptor, like many other amine receptors, is coupled to its still unidentified effector system via a G-protein and regulated by Ca2+. However, unlike the latter, the H3 receptor is down-regulated by the divalent cation.

Relationship between arterial carbon dioxide and end-tidal carbon dioxide when a nasal sampling port is used

End-tidal carbon dioxide (ETCO2) values obtained from awake nonintubated patients may prove to be useful in estimating a patient's ventilatory status. This study examined the relationship between arterial carbon dioxide tension (PaCO2) and ETCO2 during the preoperative period in 20 premedicated patients undergoing various surgical procedures. ETCO2 was sampled from a 16-gauge intravenous catheter pierced through one of the two nasal oxygen prongs and measured at various oxygen flow rates (2, 4, and 6 L/min) by an on-line ETCO2 monitor with analog display. Both peak and time-averaged values for ETCO2 were recorded. The results showed that the peak ETCO2 values (mean = 38.8 mm Hg) correlated more closely with the PaCO2 values (mean = 38.8 mm Hg; correlation coefficient r = 0.76) than did the average ETCO2 values irrespective of the oxygen flow rates. The time-averaged PaCO2-ETCO2 difference was significantly greater than the PaCO2-peak ETCO2 difference (P less than 0.001). Values for subgroups within the patient population were also analyzed, and it was shown that patients with minute respiratory rates greater than 20 but less than 30 and patients age 65 years or older did not differ from the overall studied patient population with regard to PaCO2-ETCO2 difference. A small subset of patients with respiratory rates of 30/min or greater (n = 30) did show a significant increase in the PaCO2-ETCO2 difference (P less than 0.001). It was concluded that under the conditions of this study, peak ETCO2 values did correlate with PaCO2 values and were not significantly affected by oxygen flow rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Response of children with Plasmodium falciparum to chloroquine and development of a national malaria treatment policy in Zaire

In vivo sensitivity of Plasmodium falciparum to chloroquine was evaluated in 4 of 9 regions of Zaire in 1985 to develop a national strategy for treatment of malaria. Children less than 5 years of age were treated with either a single dose of chloroquine base, 10 mg/kg, or a dose of 25 mg/kg given over 3 d. A modified 7-day World Health Organization in vivo test was used with follow-up 2, 3 and 7 d after the start of treatment. 339 children were studied. In Bwamanda 92% of children were aparasitaemic 7 days after chloroquine, 10 mg/kg, but in Kinshasa only 44% were free of parasites after 25 mg/kg chloroquine. The mean drop in parasite density among those who did not clear parasites by day 7 was greater than 98% of the initial value. Although the parasite density decreased markedly, the failure of most subjects to become aparasitaemic indicated a marked decrease in parasite sensitivity since 1983. Only one child of 51 who were initially febrile remained febrile, although 14 (28%) of these had resistant parasites. The decrease in parasitaemia and temperature, even among children with resistant strains, led the Ministry of Health to recommend 25 mg/kg chloroquine as first line treatment for fever/malaria in their national malaria control plan. The plan includes drug sensitivity surveillance and a referral system for patients who do not respond to chloroquine treatment.

Malaria infection in pregnant women in Zaire: the effects and the potential for intervention

In five maternity centres in urban and rural Zaire we evaluated the maternal prevalence of Plasmodium falciparum parasitaemia and recorded fever, the frequency of abortions and stillbirths, newborn birth weights and the feasibility of delivering antimalarial chemoprophylaxis. Women in their first and second pregnancy, compared to others (greater than or equal to third pregnancies), had a higher frequency of parasitaemia (38 v. 15%, respectively, P less than 0.001), higher parasite densities (geometric mean densities 927 per mm3 v. 277 per mm3, respectively, P = 0.01), higher rates of stillbirths and low birth weight babies (24% v. 6.4%, P less than 0.001). On average, pregnant women first attended prenatal clinics in the sixth to seventh month of gestation and made three to four visits before delivery. In these areas of Zaire, antimalarial interventions during pregnancy would have the largest impact if they were targeted to women in their first and second pregnancy. In the study areas, maternal attitudes and prenatal care-seeking behaviours do not appear to be barriers to providing an antimalarial intervention.

Specific opioid binding sites for dermorphin in rat brain. A radioreceptor assay using the tritiated hormone as primary ligand

Dermorphin, a heptapeptide amide isolated from amphibian skin, is the most potent of the naturally occurring opioid peptides. (3H)-dermorphin (52 Ci/mmol, 1294 GBq/mmol) was prepared by catalytic tritiation of the synthetic (2,5-iodotyrosyl 1,5)-dermorphin precursor. High affinity specific binding sites for dermorphin were labeled in rat brain membranes using tritiated dermorphin as primary ligand. The binding was saturable and time-dependent. Scatchard analysis revealed a single population of non-interacting high affinity sites (Kd = 0.86 nM). Dermorphin and the specific opiate antagonist naloxone inhibited specific (3H)-dermorphin binding in a concentration dependent manner. The displacement curves could be fit to a simple competitive model assuming only one population of binding sites, with IC 50 of 1.6 nM and 3.4 nM for dermorphin and naloxone, respectively. The use of tritiated dermorphin will be helpful to ascertain unequivocally the selectivity of dermorphin for the different opioid receptor subtypes in the central nervous system.

Alcohol treatment outcome evaluation methodology: state of the art 1980-1984

The methodology of alcohol treatment outcome studies published during two sequential intervals from 1976 through mid-1984 is critically reviewed. Although considerable methodological improvements have occurred over time, major methodological deficiencies continue to characterize much of the literature, with inadequate reporting of subjects' pretreatment characteristics (e.g., severity of dependence) being the most striking problem. Pervasive differences across studies regarding the types of data gathered and the ways in which findings are reported seriously impede attempts to compare studies and weaken the types of conclusions that can be drawn about treatment efficacy in general. It is suggested that journal editors establish standards of reporting for follow-up studies.

Chemically fixed human umbilical cord vein grafts as arterial substitutes: potential and limits

In spite of reported successes, synthetic fabric grafts and microporous and plain synthetic conduits have proven unsuitable for aorto-coronary bypasses and showed weaknesses below the knee. Readily available and uniform diameter vascular substitutes with biological and mechanical properties comparable to human vessels would be of paramount interest. Following reported successes with chemically fixed human umbilical veins (HUV), we have attempted to develop smaller diameter blood conduits and have improved the currently prevalent techniques of fixation, preparation and storage to generate more convenient surgical products. In vitro assessment of the processed HUV demonstrated that the HUV can be easily processed to make an arterial substitute that can be preserved either in a liquid medium or as a dry product. However, the in vivo implantations in dogs led to disappointing results for liquid-preserved or albuminated veins. Critical-point dried grafts gave better results, unfortunately they do not heal and they can only degrade after implantation.

Photoaffinity labeling of D-2 dopamine binding subunits from rat striatum, anterior pituitary and olfactory bulb with a new probe, [3H]azidosulpride

A novel photoaffinity probe [3H] azidosulpride has been developed for biochemical studies of D-2 dopamine receptors. This ligand binds to the receptors with high affinity (Kd = 3.1 +/- 0.2 nM) and, upon photoactivation, about 20% of the radioactivity bound to membranes becomes covalently incorporated. More than 90% of this irreversible binding is protectable by dopaminergic agents including D-2 selective compounds, whereas D-1 selective and non-dopaminergic compounds are ineffective. Analysis by sodium dodecylsulfate polyacrylamide gel electrophoresis reveals a single band at Mr = 85 kDa for labeled receptors in striatum, anterior pituitary or olfactory bulb, where pharmacologically distinct binding sites have been previously detected.

Identification of alcohol abuse using laboratory tests and a history of trauma

In a study involving 68 ambulatory patients with known alcohol problems and 68 social drinkers matched for age and sex, a questionnaire about the patients' history of trauma identified 7 out of 10 subjects with drinking problems. In contrast, abnormal values for gamma-glutamyl transferase, mean corpuscular volume, or high-density lipoproteins had only moderate sensitivity (26% to 40%) for identifying alcohol problems but excellent specificity (88% to 99%) for ruling out cases. Similar rates of sensitivity and specificity were found among 61 family practice patients. Diagnostic accuracy was improved by combining tests results, using computer-based logistic regression analysis. This study suggests that a brief questionnaire on history of trauma is valuable for the earlier detection of problem drinking in ambulatory populations, in contrast to laboratory tests, which appear to have high sensitivity only with more chronic alcoholics.

Microvascular blood flow: evidence indicating a cubic dependence on arteriolar diameter

The primary objectives of this study were 1) to determine the functional relationship between microvascular blood flow (Q) and arteriolar internal diameter (D) and 2) to determine whether this relationship conformed to a theoretical optimality prediction--that blood flow is proportional to the cube of the diameter (Q = kD3). Paired blood velocity and arteriolar diameter measurements in the cremaster muscle microvasculature of eight normotensive (WKY) and eight hypertensive (SHR) rats were made under control conditions and following maximal dilation of the microvasculature with topically applied adenosine. A total of 160 paired flow-diameter measurements were made in arteriolar vessels with diameters ranging from 6 to 108 micron. Analysis of this data showed that Q and D were functionally linked by Q = kDm with k = 417 and m = 3.01 with D expressed in centimeters. Confidence intervals at the 99.9% level were 331-503 and 2.86-3.14 for k and m, respectively. A theoretical development based on the minimization of the energy cost of blood volume and arteriolar wall volume led to a theoretical estimate for the range of k to be 92-132 and a value for m to be 3. Predicted pressure gradients in single vessels of the cat mesentery and shear rates in the rat cremaster based on Q = kD3 compared well with measured data reported in the literature and that determined in the present study. On the basis of the direct and predictive evidence, it is concluded that the relationship Q = kD3 represents a general average property of the microvasculature.

Role of the carboxamide groups of the asparagine and glycinamide residues of oxytocin. Syntheses and biological properties of [5-beta-cyanoalanine] oxytocin and [9-alpha-aminoacetonitrile] oxytocin

In an attempt to see whether the C=O and the NH2 of CONH2 of asparagine5 and glycinamide9 are both essential for biological activity, [5-beta-cyanoalanine] oxytocin and [9-alpha-aminoacetonitrile] oxytocin have been synthesized. Each of these analogs contains a nitrile group in place of the carboxamide group of Asn5 and GlyNH92 respectively; the nitrile group can simulate the carbonyl portion of the carboxamide, but lacks the hydrogen-bond donating capacity of its NH2 portion. Substitution of a nitrile group produced opposite biological effects in the 5 and the 9 positions; the 5-substituted analog showed very low activities (less than 3% of those of oxytocin) while the 9-substituted analog showed extremely high activities (with an in vivo uterine activity of 906 U/mg almost twice that of oxytocin). The results clearly suggest that the mechanisms of interaction of the carboxamide groups with the receptor sites are different for residues 5 and 9.

Biofunctional evaluation of two hydrogen bonds stabilizing the beta-turn in the acyclic component of oxytocin

The depsipeptide [8-alpha-hydroxyisocaproic acid, 9-glycolic amide]-oxytocin, which has ester linkages replacing the peptide linkages between the 7th and 8th and the 8th and 9th residues of oxytocin, has been synthesized by a (6 + 3) condensation of Boc-tocinoic acid with Pro-O-HyIc-O-Glyc-NH2, followed by deprotection of the resulting product. The analog exhibited the following activities in rats: 258 +/- 11 and 28 +/- 5 U/mg, uterus in vitro in the absence and presence, respectively, of Mg+2; 54 +/- 4 U/mg, uterus in vivo; 19.3 +/- 2.1 U/mg, milk ejection; 0.153 +/- 0.026 U/mg, antidiuretic activity; and no pressor activity. The need for the presence of the peptide linkages mentioned above as sources for internal hydrogen bonds to stabilize the "biologically significant" conformation is discussed.

[1-Desaminopenicillamine, 8-alpha-hydroxyisocaproic acid] oxytocin. A selective inhibitor in rats of the uterine response to oxytocin

[1-Desaminopenicillamine, 8-alpha-hydroxyisocaproic acid] oxytocin was synthesized by a 6 + 3 fragment condensation from precursors which had been formed by solution methods. This analog inhibited uterine responses to oxytocin (pA2 7.37, 7.9, 6.17; uterus in vitro without Mg++, in vitro with Mg++, and in vivo, respectively) and showed little or no activity in other bioassays.

In vitro synthesis of genome length complementary RNA of vesicular stomatitis virus in the presence of inosine 5'-triphosphate

The virion-associated RNA polymerase of vesicular stomatitis virus (VSV) synthesizes RNA in vitro when GTP is replaced by inosine 5'-triphosphate (ITP). The synthesis is optimal at an ITP concentration of 200 microM and the extent of synthesis is between 15 to 20% compared to normal transcription in the presence of GTP. Analyses of the RNA products revealed that approximately 10% of the product RNA represented plus-strand complement of the genome RNA. Defective interfering particles of VSV were also capable of synthesizing complementary RNA in the presence of ITP, in addition to 46-base RNA, although in lesser amount (2%). Since I substitution facilitates read-through of the genome RNA, these results suggest that interaction of the product RNA with the genome template or ITP-mediated modification of a viral protein may be involved in the read-through process in vitro.

Radio-labelling of 1-O-alkyl, 2-O-acetyl, sn-glycero-3-phosphorylcholine, 1-O-(9,10-di3H)-octadecyl PAF-acether

3H-labelling of 1-3H-PAF-aceter was prepared by catalytic reduction of 1-O-(9,10)-octadecenyl-2-O-benzyl-sn-glyceryl-3-phosphorylcholine and then acetylated. 5 mumoles of this dehydro derivative dissolved in methanol was treated during 4 hours with tritium gas (80 Ci) and compressed until 1.1 bar by an automatic tritium transfer unit [1]. The catalyst was removed by filtration over Millex (Millipore) and labile tritium atoms eliminated by rotatory flash evaporation. The chemical purity was checked by 3H scanning and autoradiography. It was finally recovered through preparative thin-layer chromatography and then acetylated. The specific radioactivity was found to be close to 40-50 Ci/mmole.

Enkephalin dipeptidyl carboxypeptidase (enkephalinase) activity: selective radioassay, properties, and regional distribution in human brain

The compound [3H]Tyr1,D-Ala2,Leu-OH5]enkephalin has been synthesised as a potentially selective substrate for enkephalin dipeptidyl carboxypeptidase (enkephalinase) activity in brain. Incubations in the presence of homogenates and particulate fractions from rodent and human brain result in the formation of [3H]Tyr-D-Ala-Gly, which can be conveniently isolated by polystyrene bead column chromatography. The enzyme activity responsible for the hydrolysis of the Gly3-Phe4 amide bond of this substrate displays close resemblance to that hydrolysing the natural enkephalins at the same level. In addition, enkephalinase activity characterised in postmortem human brain is closely similar to that in rodent brain, with regard to optimal pH and apparent affinities of various substrates and inhibitors, including the potent compound thiorphan. Enkephalinase activity is distributed in a highly heterogeneous fashion among regions of human brain, the highest levels being found in globus pallidus and pars reticulata of the substantia nigra. This distribution is poorly correlated with that of opiate receptor binding sites but displays some resemblance to that of reported Met5-enkephalin levels.

Biofunctional evaluation of a hydrogen bond stabilizing the conformation in the cyclic part of oxytocin

[5-beta-Malamidic acid]oxytocin was synthesized to study the importance of the hydrogen bond between the C=O of Tyr2 and the peptide N-H of Asn5 for the stabilization of a biologically functional conformation of oxytocin. This analog lacks the peptide N-H at residue 5 required for the formation of a hydrogen bond with the C-O of Tyr2. [5-beta-Malamidic acid] oxytocin exhibited 45.1 +/- 2.5 U/mg and 65.6 +/- 5.9 U/mg of uterotonic activity, in vitro, in the absence and in the presence, respectively, of Mg2+, 147 +/- 14 U/mg of uterotonic activity in vivo, 203 +/- 13 U/mg of milk-ejecting activity, 0.37 +/- 0.03 U/mg of pressor activity and 0.32 +/- 0.29 U/mg of antidiuretic activity. It is concluded that devoid of the hydrogen bond under question, an oxytocin-like peptide can still assume the conformation needed to interact with the oxytocin receptors.

Binding and metabolism studies with [3H](D-Ala2,Leu5)enkephalinamide and [3H](D-Ala2,Pro5)enkephalinamide: evidence for a selective interaction of (D-Ala2,Pro5)enkephalinamide with mu-receptors

We have compared the binding characteristics of [3H](D-Ala2,Leu5)enkephalinamide and [3H](D-Ala2,Pro5)enkephalinamide on a washed homogenate from mouse brain. The maximum number of binding sites for [3H](D-Ala2,Leu5)enkephalinamide was twice that obtained with [3H](D-Ala2,Pro5)enkephalinamide. Hill slopes of the displacement curves for opiates and (D-Ala2,Pro5)enkephalinamide obtained against [3H](D-Ala2,Leu5)enkephalinamide were considerably lower than that of (D-Ala2,Met5)enkephalinamide and (D-Ala2,Leu5)enkephalinamide. In contrast, Hill slopes for morphine, ketocyclazocine and (D-Ala2,Leu5)enkephalinamide were similar for the displacement of [3H](D-Ala2,Pro5)enkephalinamide. These results are discussed and interpreted in terms of a selective interaction for (D-Ala2,Pro5)enkephalinamide with mu-receptors and a similar affinity of (D-Ala2,Leu5)enkephalinamide for mu- and delta-receptors. Since metabolism studies did not show any difference in the degradation rate of these two enkephalin analogs, the discrepancy between in vitro and in vivo activity cannot result from the catabolism processes. Another possible explanation is proposed.

Effects of traumatic manipulations on grafts, sutures, and host arteries during vascular surgery procedures. Experiments on dogs

Scanning electron microscopy was used to diagnose incidents of trauma and the pattern of healing following surgical implantation of microporous blood vessel substitutes. Vascular reconstruction procedures using autogenous or synthetic prosthetic material inflict damage to the adjacent tissues as well as the prosthesis. This affects the thrombotic behavior and healing pattern of the area. The prognosis for long-term success are, as a consequence, directly influenced. Various vessel-occluding devices were evaluated in canine models with respect to their ability to damage blood vessels at the clamped site. The impact of suture needles on tissues and prosthetic materials was also considered. Of the various vessel-clamping devices which are commercially available, those which have elastomeric shields on the clamping components were found to be most satisfactory. The development of less traumatic surgical devices is discussed with the aim of further reducing surgical trauma.

Defibrinogenation as an alternative to heparinization in prolonged extracorporeal circulation

Complications arising from difficulty controlled bleeding and thrombus formation during procedures which require extracorporeal circulation with heparin as anticoagulant motivate the search for better hemostasis and anticoagulant technology. An enzyme (Defibrase), having a specific interaction with fibrinopeptide A such as to cause fibrin depletion in a soluble form, has been proposed as an alternative to heparin. Defibrase, in contrast to heparin, does not affect blood platelet function. Heparin and Defibrase as anticoagulants were compared in 8 h perfusion studies using arterio-venous extracorporeal blood circuits in dogs; the circuitry included pumps, membrane oxygenators and filters serially. Thrombus formation, in the filters and the oxygenators as well as pathology of the perfused animal were investigated. The results suggest that defibrase-like enzymes have potential for enhanced control of hemorrhagic and thrombotic phenomena. Although impeded by a latency of several hours before the full anticoagulant properties are developed in vivo, it appears that enzymatically mediated defibrinogenation of blood may be a valuable alternative to heparinization in extracorporeal circulation procedures.

[The treatment of fracture-dislocation of the humeral head by blind pinning (author's transl)]

The authors have treated 7 fracture-dislocations of the humeral head by blind pinning. The fractures were reduced by traction under general anaesthesia. 3 or 4 pins were then introduced into the olecranon fossa and driven up through the humeral head. After an average follow up of 29 months, the results were excellent in 9 cases, good in 5 and fair in 3. In 3 cases only, necrosis of the humeral head was noted.