Neoadjuvant concurrent chemoradiotherapy with and without hyperthermia in retroperitoneal sarcomas: feasibility, efficacy, toxicity, and long-term outcome

Purpose

Retroperitoneal (RPS) sarcomas are associated with poor local and abdominal tumor control. However, the benefit of preoperative radio- or chemotherapy alone for these entities is currently unclear. Moreover, as intermediate- and high-grade sarcomas have a tendency toward early metastasis, exploration of neoadjuvant strategies is of high importance. This analysis reports the results of our 20-year single-institution experience with preoperative neoadjuvant concurrent chemoradiation.

Methods

From 2000–2019, 27 patients with intermediate- or high-grade RPS (12 dedifferentiated liposarcoma, 10 leiomyosarcoma, 5 others) were treated with radiotherapy (median dose: 50.4 Gy; range 45–75 Gy) and two cycles of chemotherapy (doxorubicin 50 mg/m² BSA/d3 q28 and ifosfamide 1.5 g/m² BSA/d1‑5 q28) in neoadjuvant intent. Chemotherapy consisted of doxorubicin alone in two cases and ifosfamide alone in one case. Fifteen patients (56%) additionally received deep regional hyperthermia.

Results

The median follow-up time was 53 months (±56.7 months). 92% of patients received two cycles of chemotherapy as planned and 92% underwent surgery. At 5 and 10 years, abdominal-recurrence-free survival was 74.6% (±10.1%) and 66.3% (±11.9%), distant metastasis-free survival was 67.2% (±9.7%) and 59.7% (±11.1%), and overall survival was 60.3% (±10.5%) and 60.3% (±10.5%), respectively. CTC grade III and IV toxicities were leukocytopenia (85%), thrombocytopenia (33%), and anemia (11%). There were no treatment-related deaths.

Conclusion

Neoadjuvant chemoradiotherapy with and without hyperthermia for retroperitoneal sarcomas is feasible and provided high local control of intermediate- and high-grade sarcoma.

A sensitive and specific assay for the serological diagnosis of antilaminin 332 mucous membrane pemphigoid

BACKGROUND

Antilaminin 332 mucous membrane pemphigoid (MMP) is an autoimmune subepidermal blistering disease with predominant mucosal involvement and autoantibodies against laminin 332. Malignancies have been associated with this disease; however, no standardized detection system for antilaminin 332 serum antibodies is widely available.

OBJECTIVES

Development of a sensitive and specific assay for the detection of antilaminin 332 antibodies.

METHODS

An indirect immunofluorescence (IF) assay using recombinant laminin 332 was developed and probed with a large number of antilaminin 332 MMP patient sera (n = 93), as well as sera from patients with antilaminin 332-negative MMP (n = 153), bullous pemphigoid (n = 20), pemphigus vulgaris (n = 20) and noninflammatory dermatoses (n = 22), and healthy blood donors (n = 100).

RESULTS

In the novel IF assay, sensitivities with the laminin 332 heterotrimer and the individual α3, β3 and γ2 chains were 77%, 43%, 41% and 13%, respectively, with specificities of 100% for each substrate. The sensitivity for the heterotrimer increased when an anti-IgG4 enriched antitotal IgG conjugate was applied. Antilaminin 332 reactivity paralleled disease activity and was associated with malignancies in 25% of patients with antilaminin 332 MMP.

CONCLUSIONS

The novel IF-based assay will facilitate the serological diagnosis of antilaminin 332 MMP and may help to identify patients at risk of a malignancy.

MOG-IgG in primary and secondary chronic progressive multiple sclerosis: a multicenter study of 200 patients and review of the literature

Background

Antibodies to human full-length myelin oligodendrocyte glycoprotein (MOG-IgG) as detected by new-generation cell-based assays have recently been described in patients presenting with acute demyelinating disease of the central nervous system, including patients previously diagnosed with multiple sclerosis (MS). However, only limited data are available on the relevance of MOG-IgG testing in patients with chronic progressive demyelinating disease. It is unclear if patients with primary progressive MS (PPMS) or secondary progressive MS (SPMS) should routinely be tested for MOG-IgG.

Objective

To evaluate the frequency of MOG-IgG among patients classified as having PPMS or SPMS based on current diagnostic criteria.

Methods

For this purpose, we retrospectively tested serum samples of 200 patients with PPMS or SPMS for MOG-IgG using cell-based assays. In addition, we performed a review of the entire English language literature on MOG-IgG published between 2011 and 2017.

Results

None of 139 PPMS and 61 SPMS patients tested was positive for MOG-IgG. Based on a review of the literature, we identified 35 further MOG-IgG tests in patients with PPMS and 55 in patients with SPMS; the only reportedly positive sample was positive just at threshold level and was tested in a non-IgG-specific assay. In total, a single borderline positive result was observed among 290 tests.

Conclusion

Our data suggest that MOG-IgG is absent or extremely rare among patients with PPMS or SPMS. Routine screening of patients with typical PPMS/SPMS for MOG-IgG seems not to be justified.

Distribution of Mycobacterium avium subsp. paratuberculosis in a Subclinical Naturally Infected German Fleckvieh Bull

Although it has been known for years that Mycobacterium avium subsp. paratuberculosis (MAP) is detectable in the reproductive organs and semen of infected bulls, only few studies have been conducted on this topic worldwide. This study surveyed the MAP status of a bull, naturally infected due to close contact with its subclinically infected parents over a period of 4 years. From the age of 7 weeks to necropsy, faecal, blood and, after sexual maturity, semen samples were drawn repeatedly. Already at the first sampling day, MAP-DNA was detected in faeces by semi-nested PCR. True infection was confirmed by the detection of MAP-DNA in blood at the age of 40 weeks. In total, MAP-DNA was present in 25% faecal (34/139), 16% blood (23/140) and 5% semen (4/89) samples, including MAP-free intervals of up to 9 weeks. MAP genome equivalents (MAP-GE) of up to 6.3 × 10⁶ /g faeces and 1.8 × 10⁵ /ml blood were determined. Cultivation of MAP occurred only in three of 137 faecal and two of 109 blood, but never in semen samples. Over the whole period, the bull was a serological negative MAP shedder. During necropsy, 42 tissue samples were collected. Neither macroscopic nor histological lesions characteristic of a MAP infection were observed. Cultivation of MAP in tissue sections failed. However, MAP-DNA was spread widely in the host, including in tissues of the lymphatic system (7/15), digestive tract (5/14) and the urogenital tract (5/9) with concentrations of up to 3.9 × 10⁶ MAP-GE/g tissue. The study highlighted the detection of MAP in male reproductive organs and semen. It supports the hypothesis that bulls may probably transmit MAP, at least under natural mating conditions. In artificial insemination, this might not be relevant, due to antibiotics included currently in semen extenders. However, the survivability of MAP in this microenvironment should be investigated in detail.

EUROPattern Suite technology for computer-aided immunofluorescence microscopy in autoantibody diagnostics

Antinuclear autoantibodies (ANA) are highly informative biomarkers in autoimmune diagnostics. The increasing demand for effective test systems, however, has led to the development of a confusingly large variety of different platforms. One of them, the indirect immunofluorescence (IIF), is regarded as the common gold standard for ANA screening, as described in a position statement by the American College of Rheumatology in 2009. Technological solutions have been developed aimed at standardization and automation of IIF to overcome methodological limitations and subjective bias in IIF interpretation. In this review, we present the EUROPattern Suite, a system for computer-aided immunofluorescence microscopy (CAIFM) including automated acquisition of digital images and evaluation of IIF results. The system was originally designed for ANA diagnostics on human epithelial cells, but its applications have been extended with the latest system update version 1.5 to the analysis of antineutrophil cytoplasmic antibodies (ANCA) and anti-dsDNA antibodies.

[Novel software-based and validated evaluation method for objective quantification of bone regeneration in experimental bone defects]

AIM

The quantification of newly formed bone in experimental defect models is a problem in various experimental set-ups. Several methods have been described to evaluate and quantify the regeneration of newly formed bone in various animal models. Most methods only describe the amount of regenerated tissue on a semi-quantitative level, the results significantly depend on the subjective rating of the observer and such evaluation methods have not been validated in terms of objectivity and reliability. The aim of the present study was to introduce a novel evaluation method for the accurate quantification of bone regeneration on digital X-ray images using a freely available digital image software analysis programme (GIMP, GNU General Public Licence).

METHODS

The method introduced here contains 5 steps: standardisation of size and colour, determination of range of interest (ROI), defining different qualities of mineralisation, pixel analysis with histogram function, similar to the Hondsfield index, and quantification. In order to evaluate the objectivity and reliability, the quantification method was compared to semi-quantitative scores described by Mosheiff and Werntz for inter- and intraobserver variability. Six observers were asked to determine bone regeneration in 16 X-ray images of 2 different animal models. In order to describe intraobserver variability, the evaluation was repeated after a period of 4 weeks. Statistical analysis including determination of intra- and interobserver variability (Bland-Altman coefficient of reproduction) was performed using SAS software.

RESULTS

For both experimental set-ups analysed in this project (rabbit and sheep bone defects), the objectivity was significantly higher in the GIMP-based evaluation compared to the evaluation according to Mosheiff and Werntz using the Bland-Altman coefficient (rabbit: GIMP: 0.095, Mosheiff: 0.272, Werntz: 0.283; sheep: GIMP: 0.098, Mosheiff: 0.658, Werntz: 0.668). Analogous results were obtained for reliability (rabbit: GIMP: 0.086, Mosheiff: 0.221, Werntz: 0.385; sheep: GIMP: 0.102, Mosheiff: 0.339, Werntz: 0.623).

CONCLUSION

This quantification method introduced here has proved to be a reliable and "easy-to-use" tool in order to perform objective quantification of bone regeneration in 2 different experimental set-ups. It offers a more detailed and quantitative way for precise determination of regenerated tissue and is characterised by higher objectivity and reliability compared to other semi-quantitative evaluation methods. The objectivity seems to be independent of the animal model to which the method is applied.

Achieving signalling selectivity of ligands for the corticotropin-releasing factor type 1 receptor by modifying the agonist's signalling domain

BACKGROUND AND PURPOSE

Most of the pharmaceuticals target G-protein-coupled receptors (GPCRs) which can generally activate different signalling events. The aim of this study was to achieve functional selectivity of corticotropin-releasing factor receptor type 1 (CRF(1)) ligands.

EXPERIMENTAL APPROACH

We systematically substituted urocortin, a natural peptide agonist of CRF(1), with bulky amino acids (benzoyl-phenylalanine, naphthylalanine) and determined the effect of the analogues on coupling of CRF(1) to Gs- and Gi-protein in human embryonic kidney cells, using receptor binding, [(35)S]-GTPgammaS binding stimulation, and cAMP accumulation assays.

KEY RESULTS

Native ligands stimulated Gs and Gi activation through CRF(1), resulting in stimulation and then inhibition of cAMP accumulation. Single replacements in urocortin at positions 6-15 led, dependent on the position and nature of the substituent, to ligands that conserved Gs activity, but were devoid of Gi activity, only stimulating cAMP accumulation, and competitively antagonized the Gi activation by sauvagine. In contrast, analogues with substitutions outside this sequence non-selectively activated Gs and Gi, as urocortin did.

CONCLUSIONS AND IMPLICATIONS

Modifications in a specific region, which we have called the signalling domain, in the polypeptide agonist urocortin resulted in analogues that behaved as agonists and, at the same time, antagonists for the activation of different G-proteins by CRF(1). This finding implies significant differences between active conformations of the receptor when coupled to different G-proteins. A similar structural encoding of signalling information in other polypeptide hormone receptor ligands would result in a general concept for the development of signalling-selective drug candidates.

Corticotropin releasing hormone and related peptides can act as bioregulatory factors in human keratinocytes

Following previous findings in human skin of the functional expression of genes for the corticotropin releasing hormone (CRH) receptor type 1 (CRH-R1) and CRH itself, we searched for local phenotypic effects for peptides related to CRH. We now report that CRH, sauvagine, and urocortin inhibit proliferation of human HaCaT keratinocytes in a dose-dependent manner. The peptides produced variable cyclic adenosine 3':5'-monophosphate stimulation, with CRH having the highest potency. Binding of iodine 125 CRH to intact keratinocytes was inhibited by increasing doses of CRH, sauvagine, or urocortin, all showing equal inhibitory potency. Immunocytochemistry identified CRH-R1 immunoreactivity in HaCaT keratinocytes. In conclusion, CRH (exogenous or produced locally) and the related urocortin and sauvagine peptides can modify human keratinocyte phenotype through a receptor-mediated pathway.

A role for a helical connector between two receptor binding sites of a long-chain peptide hormone

The conformational freedom of single-chain peptide hormones, such as the 41-amino acid hormone corticotropin releasing factor (CRF), is a major obstacle to the determination of their biologically relevant conformation, and thus hampers insights into the mechanism of ligand-receptor interaction. Since N- and C-terminal truncations of CRF lead to loss of biological activity, it has been thought that almost the entire peptide is essential for receptor activation. Here we show the existence of two segregated receptor binding sites at the N and C termini of CRF, connection of which is essential for receptor binding and activation. Connection of the two binding sites by highly flexible epsilon-aminocaproic acid residues resulted in CRF analogues that remained full, although weak agonists (EC(50): 100-300 nM) independent of linker length. Connection of the two sites by an appropriate helical peptide led to a very potent analogue, which adopted, in contrast to CRF itself, a stable, monomer conformation in aqueous solution. Analogues in which the two sites were connected by helical linkers of different lengths were potent agonists; their significantly different biopotencies (EC(50): 0.6-50 nM), however, suggest the relative orientation between the two binding sites rather than the maintenance of a distinct distance between them to be essential for a high potency.

Cutaneous expression of CRH and CRH-R. Is there a "skin stress response system?"

The classical neuroendocrine pathway for response to systemic stress is by hypothalamic release of corticotropin releasing hormone (CRH), subsequent activation of pituitary CRH receptors (CRH-R), and production and release of proopiomelanocortin (POMC) derived peptides. It has been proposed that an equivalent to the hypothalamic-pituitary-adrenal axis functions in mammalian skin, in response to local stress (see Reference 1). To further define such system we used immunocytochemistry, RP-HPLC separation, and RIA techniques, in rodent and human skin, and in cultured normal and malignant melanocytes and keratinocytes. Production of mRNA for CRH-R1 was documented in mouse and human skin using RT-PCR and Northern blot techniques; CRH binding sites and CRH-R1 protein were also identified. Addition of CRH to immortalized human keratinocytes, and to rodent and human melanoma cells induced rapid, specific, and dose-dependent increases in intracellular Ca2+. The latter were inhibited by the CRH antagonist alpha-helical-CRH(9-41) and by the depletion of extracellular calcium with EGTA. CRH production was enhanced by ultraviolet light radiation and forskolin (a stimulator for intracellular cAMP production), and inhibited by dexamethasone. Thus, evidence that skin cells, both produce CRH and express functional CRH-R1, supports the existence of a local CRH/CRH-R neuroendocrine pathway that may be activated within the context of a skin stress response system.

Thiol-induced nitric oxide release from 3-halogeno-3,4-dihydrodiazete 1,2-dioxides

In this work we studied the mechanism of nitric oxide (NO) release underlying the vasorelaxant and antiaggregant effect of 3,4-dihydrodiazete 1,2-dioxides (DD). Six derivatives were included in the investigations, namely, 3-bromo- and 3-chloro-3,4,4-trimethyl-DD (1a,b), 3-bromo- and 3-chloro-4-methyl-3,4-hexamethylene-DD (2a,b), 3,3,4,4-tetramethyl-DD (3), and 3-methyl-3,4-hexamethylene-DD (4), and their reactivity toward thiols was analyzed. The 3-bromo- and 3-chloro-DD derivatives were found to react with thiols; this reaction can lead to NO formation, DD 2a being the most reactive compound. 2-(Hydroxyamino)-2-methylbutan-3-one oxime (5a) and 2-hydroxy-2-methylbutan-3-one oxime (6) were the main products isolated from the reaction of 1a with cysteine. Reaction rates of DD with thiols were dependent upon pH and concentration of the reagents. Maximum rates of NO release corresponded to thiol concentrations in the range of 1 mM. Consistent with reaction kinetics data and products isolated, a reaction mechanism was proposed. Addition of 2a to bovine aortic endothelial cells led to strong NO release indicating a reaction with endogenous thiols. In rat mesenterial arteries, the vasorelaxant action of 2a was only slightly influenced by addition of thiol to the incubation medium. For the most reactive DD derivatives, cytotoxic effects were observed at concentrations roughly 2 orders of magnitude higher than those inducing vasorelaxation.

Hair cycle-dependent expression of corticotropin-releasing factor (CRF) and CRF receptors in murine skin

We demonstrate the presence and hair cycle-dependent expression of corticotropin-releasing factor (CRF) and CRF receptors (CRF-R) in C57BL/6 mouse skin. To correlate this with a physiological, developmentally controlled tissue remodeling process, we have analyzed CRF and CRF-R expression during defined stages of the murine hair cycle with its rhythmic changes between growth (anagen), regression (catagen), and resting (telogen). Using reversed-phase HPLC combined with two independent anti-CRF radioimmunoassays, we have identified CRF in murine skin. Maximal CRF levels were found in anagen III-IV skin, and minimal values were detected in catagen and telogen skin. By immunofluorescence, maximal CRF immunoreactivity (CRF-IR) was seen in the basal epidermis, nerve bundles of skin, the outer root sheath and matrix region of anagen IV-VI follicles, and in defined sections of their perifollicular neural network, whereas catagen and telogen skin displayed minimal CRF-IR. Using quantitative autoradiography and 125I-CRF as a tracer, high-affinity binding sites for CRF were detected in murine skin. The highest density of specific binding sites was detected in the panniculus carnosus, the epidermis, and the hair follicle. CRF-R type 1 (CRF-R1) IR was detected by immunohistology mainly in the outer root sheath, hair matrix, and dermal papilla of anagen VI follicles, as well as in the inner and outer root sheaths of early catagen follicles. CRF-R1 expression was also hair cycle dependent. Therefore, in normal murine skin, the CRF-CRF-R signaling system may operate as an additional neuroendocrine pathway regulating skin functions, possibly in the context of cutaneous stress responses.

Influence of continuous levels of fentanyl in rats on the mu-opioid receptor in the central nervous system

The highly potent and efficacious mu-opioid agonist fentanyl was SC infused into rats with submaximal analgesic doses (0-1.14 mumol/kg/day) continuously for 8 days, checked by the constant daily urinary recovery of intact drug (0.43 +/- 0.031% of the daily dose). Tail-flick latencies measured at 24 (day 1) and 48 h (day 2) after starting the infusion were increased in a dose-dependent fashion compared with those before the infusion (day 0). However, at day 8, the latencies were increased only weakly, not significantly, revealing tolerance to the antinociceptive activity of fentanyl. Fentanyl at all doses showed no significant effect on the capacity (Bmax) and affinity (Kd) of the mu-opioid receptor binding of DAMGO to whole brain (Bmax 126.2 +/- 3.00 fmol/mg protein, Kd 1.00 +/- 0.04 nM) and spinal cord (Bmax 48.24 +/- 2.71 fmol/mg protein, Kd 1.93 +/- 0.13 nM) membranes gained from the rats after killing them at day 8. Gpp(NH)p increased the Kd for brain and spinal cord sites by 3.09 and 2.65, respectively, independent of the fentanyl dose. The infusion with fentanyl did not after the basal and forskolin-stimulated adenylate cyclase activity in the whole brain membranes, nor did it change the inhibition of the forskolin-stimulated activity by DAMGO. It is concluded that, in rats, constant long-term body levels of highly potent mu-agonists result in a tolerant state that, however, does not produce overall changes in the parameters of their specific receptor sites in the CNS, i.e., receptor capacity and affinity, and in the events closely related to them, i.e., their regulation by GTP and of adenylate cyclase. This does not exclude such possible changes to be restricted to specific regions in the CNS.

Height increase, neuromuscular function, and back pain during 6 degrees head-down tilt with traction

BACKGROUND

Spinal lengthening and back pain are commonly experienced by astronauts exposed to microgravity.

METHODS

To develop a ground-based simulation for spinal adaptation to microgravity, we investigated height increase, neuromuscular function and back pain in 6 subjects all of whom underwent two forms of bed rest for 3 d. One form consisted of 6 degrees of head-down tilt (HDT) with balanced traction, while the other was horizontal bed rest (HBR). Subjects had a 2-week recovery period in between the studies.

RESULTS

Total body and spinal length increased significantly more and the subjects had significantly more back pain during HDT with balanced traction compared to HBR. The distance between the lower endplate of L4 and upper endplate of S1, as measured by ultrasonography, increased significantly in both treatments to the same degree. Intramuscular pressures in the erector spinae muscles and ankle torque measurements during plantarflexion and dorsiflexion did not change significantly during either treatment.

CONCLUSION

Compared to HBR, HDT with balanced traction may be a better method to simulate changes of total body and spinal lengths, as well as back pain seen in microgravity.

Corticotropin-releasing hormone (CRH) receptors in the mesenteric small arteries of rats resemble the (2)-subtype

The potencies of the corticotropin-releasing hormone (CRH) agonistic peptides oCRH, h/rCRH, frog sauvagine, and carp urotensin I and of the antagonistic peptide alpha-helical CRH9-41 were compared in 3 different in vitro assays: (a) receptor binding to rat brain membranes; (b) release of ACTH/beta-endorphin from rat pituitary cells; and (c) relaxation of rat mesenteric small arteries. From their potency profiles, especially from the high potency of sauvagine relative to CRH in the relaxation assay, it is concluded that the receptors mediating the hypotensive action of systemic CRH in vascular smooth muscle are different from those in the pituitary and brain, and may be identical or very similar to the recently cloned new CRH receptor type 2.

A single-point slight alteration set as a tool for structure-activity relationship studies of ovine corticotropin releasing factor

In order to determine which amino acid side chains of ovine corticotropin releasing factor (oCRF) are most sensitive to alterations with respect to receptor binding and activation, we synthesized a single-point replacement set by replacing each residue by a similar, preferably proteinogenic amino acid, maintaining a minimal change of character at each position (Ser by Thr, Gln by Asn, Glu by Asp, Arg by Lys, and vice versa, Pro by N-MeAla, Ile by Leu, Leu by Nle, Phe by Trp, His by Ala, Val by Leu, Met by Nle, Ala by Leu). In general, any loss in the biological potency by a single-point substitution in oCRF parallels a decrease in receptor binding, indicating that, in contrast to previous suggestions, there is no specific side chain in the peptide that is more responsible for receptor activation than for receptor binding. In addition to Arg(16), Ala(31), and Arg(35), amino acid residues in the N-terminal sequence (5-14) were found to be sensitive to alteration, demonstrating their particular importance for the receptor interaction of CRF agonists. Most of the analogs tested exhibited agonistic potencies in an in vitro pituitary cell culture assay at a concentration of 0.3 nM, and all analogs showed full agonistic potency at 1 microM. In contrast to the results of an alanine replacement study, the strongest decrease in receptor binding and biological potency was observed for analogs with substitutions of hydrophilic amino acids Ser(7), Arg(16), Glu(17), or Asn(34). In the case of Ser(7) and Arg(16), side chain specific interactions with the receptor may be required for high affinity. Alanine replacements at positions 17 or 34 resulted in analogs that were as potent as oCRF, while replacement of Glu(17) by Asp or Asn(34) by Gln caused a dramatic loss in potency, thereby suggesting an important effect at sterically or conformationally sensitive positions. In contrast to corresponding alanine analogs which exhibited a significant loss in biological potency, slight alterations of lipophilic side chains at positions 6, 12, or 38 did not cause a significant reduction of receptor binding and activation, indicating that it is not specific side chains but rather lipophilicity which is essential at these positions. Indeed, replacement of Phe(12) by Trp provides an agonist with significantly increased receptor binding and biological potency.

Hair growth induction by substance P

BACKGROUND

In vitro, some neuropeptides, including the tachykinin, substance P (SP), act as growth factors. The cyclic growth of the richly innervated hair follicle offers a model for probing such functions in a complex, developmentally regulated tissue interaction system under physiologic conditions. Dissecting the role of neuropeptides in this system may also reveal as yet obscure neural mechanisms of hair growth control.

EXPERIMENTAL DESIGN

The neuropeptide-releasing neurotoxin, capsaicin was injected intradermally, or SP slow-release formulations were implanted subcutaneously in the back skin of C57BL/6 mice with all follicles in the resting stage of the hair cycle (telogen) in order to see whether this induced hair growth (anagen). In addition, the endogenous SP skin concentration and the activity of the main SP-degrading enzyme, neutral endopeptidase, were determined during the induced murine hair cycle by high performance liquid chromatography-controlled radioimmuno-assay (SP) or by fluorometry (neutral endopeptidase).

RESULTS

Both capsaicin and SP induced significant hair growth (anagen) in the back skin of telogen mice. This was associated with substantial mast cell degranulation. The endogenous SP skin concentration showed significant, hair cycle-dependent fluctuations during the induced murine hair cycle, which were largely independent of the activity of neutral endopeptidase.

CONCLUSIONS

SP may play a role in the neural control of hair growth. Whereas this pilot study does not address the underlying mechanisms of action, it demonstrates that SP has potential as a hair growth-stimulatory agent in vivo, and serves as a basis for exploring the role of tachykinins in epithelial-mesenchymal-neuroectodermal interaction systems like the hair follicle.

The effect of increasing levels of fish oil-containing structured triglycerides on protein metabolism in parenterally fed rats stressed by burn plus endotoxin

This report investigates the effect of various levels of medium-chain/fish oil structured triglycerides on protein and energy metabolism in hypermetabolic rats. Male Sprague-Dawley rats (192 to 226 g) were continuously infused with isovolemic diets that provided 200 kcal/kg per day and 2 g of amino acid nitrogen per kilogram per day. The percentage of nonnitrogen calories as structured triglyceride was varied: no fat, 5%, 15%, or 30%. A 30% long-chain triglyceride diet was also provided as a control to compare the protein-sparing abilities of these two types of fat. Nitrogen excretion, plasma albumin, plasma triglycerides, and whole-body and liver and muscle protein kinetics were determined after 3 days of feeding. Whole-body protein breakdown, flux, and oxidation were similar in all groups. The 15% structured triglyceride diet maximized whole-body protein synthesis (p < .05). Liver fractional synthetic rate was significantly greater in animals receiving 5% of nonprotein calories as structured triglyceride (p < .05). Muscle fractional synthetic rate was unchanged. Plasma triglycerides were markedly elevated in the 30% structured triglyceride-fed rats. The 30% structured triglyceride diet maintained plasma albumin levels better than those diets containing no fat, 5% medium-chain triglyceride/fish oil structured triglyceride, or 30% long-chain triglycerides. Nitrogen excretion was lower in animals receiving 30% of nonnitrogen calories as a structured triglyceride than in those receiving 30% as long-chain triglycerides, but this difference did not reach statistical significance (p = .1). These data suggest that protein metabolism is optimized when structured triglyceride is provided at relatively low dietary fat intakes.

In-vivo release of a GnRH agonist from a slow-release poly(lactide-glycolide) copolymer preparation: comparison in rat, rabbit and guinea-pig

Different batches of 50:50 poly((+-)-lactide-glycolide) copolymer (PLG) were used as biodegradable carriers for D-Phe6-gonadotropin-releasing hormone (GnRHa) in the form of injectable long-acting implants loaded with 10% GnRHa and tracer amounts of [125I]GnRHa. After their injection subcutaneously into rats, rabbits, and guinea-pigs, the release kinetics of the peptide were determined by counting the radioactivity remaining in the implants (i) after recovery from the rats after death or (ii) directly on the skin above the injection site of rabbits and guinea-pigs in-vivo. No significant differences in the release pattern of the peptide amongst the three species whether the release process was controlled by diffusion or by degradation of the polymeric matrix were found. It is concluded that the results of in-vivo release tests using laboratory animals are valid for man and that enzymes are not involved in the degradation of the polymeric matrix. The results may be of general importance for the use of long-term release PLG formulations of highly active drugs, especially peptides and proteins.

CT findings in tuboovarian abscess

As there are little data in the radiologic literature regarding the CT appearance of and the associated findings of tuboovarian abscesses (TOA), we retrospectively reviewed CT from seven patients with nine TOAs. They were bilateral in two patients and unilateral in the remaining five. The most common appearance of these abscesses was that of a somewhat tubular septated cystic pelvic mass with uniform wall thickness and with loss of fat planes between the mass and the adjacent pelvic organs (usually the uterus when present). Ipsilateral ureterectasis was also seen in four of nine lesions. Although these findings are not specific for TOA, they should be considered when pelvic masses having the above configuration are seen on CT.

[The influence of viscosity-increasing pharmaceutic aids on the liberation of the peptide gonadotropin releasing hormone (GnRH) in solution]

The in vitro liberation of the peptide hormone GnRH from polymer solutions was studied as a function of the viscosity of the polymer solutions. The liberation experiments were performed with a flow through dialysis apparatus. From solutions of dextran, carboxymethylcellulose, hydroxyethylcellulose, and polyvinylpyrrolidone the release of GnRH is prolonged whereas the release of GnRH from highly viscous solutions of methylcellulose and polyacrylic acid is not. The delivery process was found to be diffusion-controlled in solutions of dextran, carboxymethylcellulose, and hydroxyethylcellulose. In solutions of polyvinylpyrrolidone the diffusion-controlled prolongation of the GnRH release is additionally influenced by binding of the peptide to the polymer. The results imply that in these polymer solutions the diffusion coefficient of GnRH does not obey the classical relation D approximately 1/eta which is often used to predict liberation from viscous solutions. Thus, the measured macroscopic viscosity of the polymer solutions is not relevant for the diffusion-controlled prolongation of the in vitro release of GnRH. This phenomenon can be explained by the obstruction effect and the microviscosity of the polymer solutions. The described rapid and simple method can be applied for the quantitative determination of the prolonged release in polymer solutions based on diffusion-controlled processes and is useful in the comparison of the efficacy of various polymeric additives. Furthermore the method allows the quantitative proof of the decrease of diffusion in viscous low-molecular solutions and the proof of prolongations of delivery due to the binding of the investigated drug to the polymer.