Haupt- und seitenkettenkristallinität bei isotaktischen poly(1-alkyläthylen)en, 1. Thermoanalytische und röntgenographische untersuchungen an den höheren homologen

The main-chain and side-chain crystallinity of several isotactic poly(1-alkylethylene)s from poly(1-dodecylethylene) to poly(1-eicosylethylene) have been investigated by X-ray diffraction and thermoanalysis. The DSC curves of the samples which were melted and rapidly quenched indicate three first-order transitions. At low temperatures a crystal modification with an arrangement of closely packed parallel side-chains is observed. Heating of the samples changes the modification: The main-chains crystallize in a helical conformation, the side-chains assume an orthorhombic order. The side-chain crystallinity of the higher homologues of poly(1-alkylethylene)s predominates if the number of methylene groups in the side-chains increases.     

Untersuchungen zu Modifikationen von Polyamid-6 und Polyamid-4 mit eingelagerten Alkalihalogeniden

Polyamide-6 (PA-6) and polyamide-4 (PA-4) doped with alkali halides were investigated by X-ray diffraction, thermal analysis, infrared and far infrared spectroscopy at various temperatures (10 K – 300 K). The solubility of the alkali halides in PA-4 is better than in PA-6. Small ions are molecularly dispersed in PA-6 and PA-4. Alkali ions are coordinated to the oxygen, halide ions to the nitrogen of the amide group. The degree of crystallinity of the polyamides depends on the concentration of the alkali halides and the ion radii. Alkali halides stabilize modifications of the polyamides with not fully extended chains. In polyamides crystallized from the melt some alkali halides stabilized the γ-modification or similar structures. The modification is nearly independent of the alkali halide concentration and will not be destroyed by washing out the alkali halides. If the polyamides are crystallized from formic acid, alkali halides promote a pleated sheet structure with antiparallel chains. The factor group of the layer is D₂, indicated by a low temperature splitting of the B₂ vibration modes.     

Rapid regression of Kaposi’s sarcoma of the hard palate under therapy with boosted elvitegravir-containing fixdose antiretroviral combination therapy

Introduction

Kaposi’s sarcoma (KS) is a rare vascular tumor that may occur in a severe, rapidly progressive form, namely in HIV/AIDS patients. HIV-associated KS mainly affects the skin and mucous membranes.

Case presentation

We report about an HIV-positive patient who presented with an exophytic growing tumor in the region of the hard palate and severe problems regarding his dental status. Histological examination revealed evidence of AIDS-related KS. Antiretroviral therapy initiation with elvitegravir/cobicistat/emtricitabine(FTC)/tenofovirdisoproxilfumarat (E/c/F/T-fix dose combination) resulted in rapid complete remission of the KS within 2 months.

Conclusion

In this case of a treatment-naive HIV-infected patient with coexisting KS, antiretroviral therapy with E/c/FTC/TDF was very well suited to achieve rapid complete remission of KS.

     

Radical resection and liver grafting as the two main components of surgical strategy in the treatment of proximal bile duct cancer

In the treatment of adenocarcinoma of the proximal bile duct, our current strategy is to resect the tumor radically and to offer patients with unresectable tumors the chance of hepatic transplantation, if extrahepatic tumor growth is exluded. Tumor resection is performed by resection of the hilum alone or combined with partial hepatectomy. The latter procedure enables radical treatment of more advanced tumor stages and, eventually, a higher degree of radically is achieved, and is recommended. This concept is based on our experience with 108 patients with proximal bile duct carcinoma operated on between February, 1975 and October, 1986. In 10 patients, no therapeutic or palliative surgical procedure could be performed during laparotomy because of advanced tumor stage. In 30 patients, various drainage procedures were performed. Fifty-two patients underwent resection: 25 underwent resection of the hilum only, and 27 underwent resection of the hilum combined with partial liver resection. Twenty-eight of these resections were classified as curative and 24 as palliative. Sixteen patients with unresectable tumors had hepatic transplantation. In 7 of these patients, extrahepatic tumor growth was already present at the time of liver transplantation. Median survival times were: laparotomy only, 1 month; drainage procedures, 5 months; total resection, 15 months; curative resection, 23 months; palliative resection, 7 months; liver grafting, 16 months. Seven patients are alive up to 21 months posttransplantation. On the basis of favorable results in our more recent group of patients, liver grafting as the ultimate chance for tumor removal in patients otherwise treatable only by palliative drainage procedures may be justified.

---

Resumen Nuestra estrategia actual en el tratamiento del adenocarcinoma de la porción proximal del canal biliar es la resección radical del tumor y, para los pacientes con tumores no resecables, la posibilidad de trasplante hepático si se ha demostrado que no hay crecimiento tumoral extrahepático. La resección tumoral es realizada mediante la resección del hilio solamente o combinada con hepatectomía parcial. Este Último procedimiento, que hace posible el tratamiento radical de los estados tumorales más avanzados y que eventualmente logra un mayor grado de radicalidad, es el recomendado. El concepto se fundamenta en la experiencia con 108 pacientes con carcinoma del canal biliar proximal operados entre febrero de 1975 y octubre de 1986.En 10 pacientes no fue posible realizar procedimiento alguno de tipo terapéutico o paliativo durante la laparotomía debido al avanzado estado del tumor. Diversos procedimientos de drenaje fueron ejecutados en 30 pacientes. Cincuenta y dos pacientes fueron sometidos a resección, 25 con resección del hilio solamente, 27 con resección combinada con resección parcial del hígado; 28 de las resecciones fueron clasificadas como curativas y 24 como paliativas; 16 pacientes con tumores no resecables reciberion trasplante hepático, y en 7 de ellos había crecimiento tumoral extrahepático en el momento del trasplante hepático.Las supervivencias medias fueron: laparotomía, 1 mes; procedimientos de drenaje, 5 meses; resección total, 15 meses; resección curativa, 23 meses; resección paliativa, 7 meses; trasplante hepático, 16 meses. Siete pacientes se hallan vivos a los 21 meses posttrasplante. Con base en los resultados favorables en el grupo más reciente de nuestros pacientes, el trasplante de hígado como la Última posibilidad de remoción del tumor en pacientes que no podrían ser tratados sino mediante procedimientos paliativos de drenaje, puede estar justificado.

---

Résumé Pour traiter le cancer de la partie supérieure de l'arbre biliaire la stratégie actuelle des auteurs est de procéder à l'exérèse radicale de la tumeur ou de pratiquer une transplantation lorsque la tumeur ne peut Être réséquée dès lors qu'il n'y a pas d'extension extra-hépatique du processus tumoral. L'exérèse de la tumeur est effectuée par résection isolée du hile biliaire ou résection associée de la lésion et d'un segment du foie; cette dernière méthode qui s'applique aux cancers plus étendus est recommandée car plus radicale. Leur conception repose sur leur expérience concernant 108 cas opérés de février 1975 à octobre 1986.Chez 10 malades aucune intervention radicale ou palliative ne put Être pratiquée en raison du stade avancé de la tumeur. Chez 30 patients: différentes opérations de drainage furent pratiquées. En revanche, 52 sujets subirent une exérèse: 25 une résection biliaire, 27 une résection du hile associée à une hépatectomie partielle; 28 de ces résections étant considérées comme opération palliative, 24 comme palliative. Seize malades qui présentaient une lésion inacessible à l'exérèse ont été traités par une transplantation hépatique mais 7 d'entre eux accusèrent ultérieurement une extension extra-hépatique du processus tumoral.Les temps de survie furent de 1 mois après laparotomie, 5 mois après intervention de drainage, 15 mois après résection, 23 mois après opération dite curative, 7 mois après opération dite palliative, 21 mois après transplantation chez 7 malades. En raison des résultats favorables chez les derniers malades, la transplantation hépatique constitue pour les auteurs l'ultime chance de traitement radical des patients qui relèveraient autrement d'une opération palliative de drainage du fait de l'importance de la tumeur.

     

Variant of Group B Lacking the B Antigen on the Red Cells

Abstract. A group B variant, lacking B antigen on the red cells, but secreting small amounts of B substance in the saliva is described. Family investigation showed both parents and three sibs to be normal B. Among six children no normal or abnormal B occurred. It is discussed whether the B variant is due to mutation of the B gene or to the effect of a recessive suppressor gene.