In vitro noncontact intravascular femtosecond laser surgery in models of branch retinal vein occlusion

PURPOSE: To investigate intravenous femtosecond laser surgery in models of branch retinal vein occlusion. MATERIALS AND METHODS: Non-amplified near infrared femtosecond laser was used to ablate polyamide sutures and human hairs inserted into the vascular lumina of porcine retinal veins in vitro. Specimens were subjected to multiphoton laser scanning microscopy and electron microscopy. RESULTS: Regular laser cuts within sutures and hairs were detected with laser microscopy and electron microscopy. Neither laser microscopy nor histology revealed collateral damage of the vascular wall. CONCLUSIONS: Non-amplified femtosecond lasers may allow precise atraumatic non-contact intravenous retinal surgery controlled by high-resolution imaging of the target.     

Storage of Buffy‐coat‐derived platelets in additive solutions: in vitro effects on platelets prepared by the novel TACSI system and stored in plastic containers with different gas permeability

Background The novel TACSI system is designed for automated preparation of platelets (PLTs) from pooled buffy coats (BCs). One TACSI device will handle 6 units at the same time. The aim of our in vitro study is to investigate the effects of using this automated equipment with subsequent storage in two different plastic containers and to compare these results with PLTs prepared by the OrbiSac system. Study design and methods Buffy‐coat‐derived PLTs (n = 8) were prepared by using the TACSI system, including storage in polyvinyl chloride (PVC)‐based plastic containers with di, n‐decyl phthalate (DnDP) (TACSI R) and BTHC (TACSI T)‐based plasticizers. As a reference, the OrbiSac System was used to prepare PLTs (n = 8) with subsequent storage in a PVC plastic container with a citrate‐based plasticizer (BTHC). In total, 16 TACSI and eight reference units, supplied by approximately 30% plasma and 70% SSP+, were analysed for various in vitro variables during the 7‐day storage period. Results No significant difference in PLT counts, LDH, mean platelet volume (MPV) and adenosine triphosphate between the groups was detected. Glucose was lower (P < 0·05) and lactate was higher (P < 0·05) in TACSI R vs. OrbiSac. With exception of day 7 (P < 0·05 TACSI R vs. OrbiSac), HSR reactivity were not different between groups. Extent of shape change was lower and CD62P higher in TACSI T when compared with TACSI R and OrbiSac units (P < 0·05). pH was maintained at >6·8 (day 7) and swirling remained at the highest level (score = 2) for all units throughout storage. Conclusion Platelets prepared by the TACSI system with subsequent storage in two different PVC‐based plastic containers were equivalent to reference PLTs with regard to in vitro characteristics during 7 days of storage.     

Observations on the microvasculature of bone defects filled with biodegradable nanoparticulate hydroxyapatite

The microvascularization of metaphyseal bone defects filled with nanoparticulate, biodegradable hydroxyapatite biomaterial with and without platelet factors enrichment was investigated in a minipig model. Results from morphological analysis and PECAM-1 immunohistochemistry showed the formation of new blood vessels into the bone defects by sprouting and intussusception of pre-existing ones. However, no significant differences were observed in the microvascularization of the different biomaterials applied (pure versus platelet factors-enriched hydroxyapatite), concerning the number of vessels and their morphological structure at day 20 after operation. The appearance of VEGFR-2 positive endothelial progenitor cells in the connective tissue between hydroxyapatite particles was also found to be independent from platelet factors enrichment of the hydroxyapatite bone substitute. In both groups formation of lymphatic vessels was detected with a podoplanin antibody. No differences were noted between HA/PLF- and HA/PLF+ implants with respect to the podoplanin expression level, the staining pattern or number of lymphatic vessels. In conclusion, the present study demonstrates different mechanisms of blood and lymphatic vessel formation in hydroxyapatite implants in minipigs.     

Lung metastases--can resection also be justified in synchronous liver metastasis?

There is general agreement on the preconditions necessary for the resection of lung metastases: the primary tumor has to be resected completely, a local tumor recurrence as well as metastases in other organs have to be excluded. 5-year survival rate of patients operated under these criteria is said to be about 20 to 40% (number of own patients: 72; 5-year survival rate: 30.2%. Only in a few cases, however, lack of metastases in other organs is given. Often there are synchronic liver metastases. Local intraarterial chemotherapy doesn't put much burden on the patient, induces a decrease of liver metastases in 30% and a complete remission in a few cases, respectively. Between 1981 and 1987 we performed local chemotherapy of the liver in 575 patients. 110 patients showed lung metastases in the course of the treatment or during the aftercare period. In 8 patients we resected lung metastases occurring after remission of liver metastases. 7 patients died 11 to 28 months after the operation, 1 patient is still alive 16 months postoperatively.     

Somatostatin in small intestine fistulas

Somatostatin (GIF) was administered to a patient with persisting intestinal fistulas. Somatostatin reduced the tryptical activity of the secretions which subsequently subsided.     

38. Kalter Strumaknoten — Enucleation oder Resektion

Zusammenfassung Von 2408 Schilddrüseneingriffen, die in den Jahren 1969–1984 an der Chirurgischen Universitätsklinik Gießen durchgeführt wurden, lagen bei 72,5 % der Patienten szintigraphisch kalte Knoten vor. Nur in der Hälfte aller Fälle von kalten Knoten stellte der kalte Knoten auch die Indikation zur Operation dar. Zeigt sich die intraoperativ freigelegte Schilddrüse weder malignomverdächtig noch weitergehend regressiv verändert, so wird der Knoten durch eine Segmentresektion entfernt. Damit erhält der Pathologe ausreichend umgebendes Gewebe, wodurch die Diagnose eines evtl. hochdifferenzierten Carcinoms anhand der Kapselinvasion sicher gestellt werden kann.     

Activation of the bone morphogenetic protein signaling pathway induces inhibin beta(B)-subunit mRNA and secreted inhibin B levels in cultured human granulosa-luteal cells

During the human menstrual cycle the circulating levels of inhibin B, a dimer of inhibin alpha- and beta(B)-subunits, fluctuate in a fashion distinct from that of inhibin A, the alpha-beta(A)-subunit dimer. This suggests that human inhibin subunits are each regulated in a distinct manner in human ovarian granulosa cells by endocrine and local factors. We have previously shown using cultures of human granulosa-luteal (hGL) cells that gonadotropins stimulate the steady state mRNA levels of inhibin alpha- and beta(A)-subunits, but not those of the beta(B)-subunit, which, on the other hand, are up-regulated by, for instance, activin and TGF beta. We recently identified the TGF beta gene family member bone morphogenetic protein-3 (BMP-3) as a granulosa cell-derived growth factor, but whether BMP-3 or other structurally related BMPs regulate human granulosa cell inhibin production is not known. We show here that hGL cells express mRNAs for distinct serine/threonine kinase receptors (BMP-RIA and BMP-RII) and Smad signaling proteins (Smad1, Smad4, and Smad5) involved in the mediation of cellular effects of BMPs. Subsequently, we determined in hGL cell cultures the effects of distinct members of the BMP family previously found to be expressed in mammalian ovaries. Recombinant BMP-2 induces potently in a time- and concentration-dependent manner the expression of the inhibin beta(B)-subunit mRNAs in hGL cells without affecting the levels of alpha- or beta(A)-subunit mRNAs. BMP-6 has a similar, but weaker, effect than BMP-2, whereas BMP-3 and its close homolog, BMP-3b (also known as growth differentiation factor-10) had no effect on inhibin subunit mRNA expression. hCG treatment of hGL cells was previously shown to abolish the stimulatory effect of activin on beta(B)-subunit mRNA levels, and here hCG is also shown to suppress the effect of BMP-2. Furthermore, BMP-2 stimulates hGL cell secreted dimeric inhibin B levels in a concentration-dependent manner. Depending on the experiment, maximal increases in inhibin B levels of 6- to 28-fold above basal levels were detected during a 72-h culture period. We conclude that activation of the BMP-signaling pathway in hGL cells stimulates inhibin beta(B)-subunit mRNA levels and leads at the protein level to a dramatic stimulation of secreted inhibin B dimers. Our results are consistent with the suggestion that in addition to the distinct activin- and TGF beta-activated signaling pathways, the BMP-activated pathway is likely to be implicated in the complex regulation of inhibins in the human ovary.