Perioperative Platelet Count Ratio Predicts Long-Term Survival after Left Pancreatectomy and Splenectomy for Pancreatic Adenocarcinoma

BACKGROUND

The value of platelet characteristics as a prognostic factor in patients with pancreatic adenocarcinoma (PDAC) remains unclear.

METHODS

We assessed the prognostic ability of post-splenectomy thrombocytosis in patients who underwent left pancreatectomy for PDAC. Perioperative platelet count ratio (PPR), defined as the ratio between the maximum platelet count during the first five days following surgery and the preoperative level, was assessed in relation to long-term outcomes in patients who underwent left pancreatectomy for PDAC between November 2008 and October 2022.

RESULTS

A comparative cohort of 245 patients who underwent pancreaticoduodenectomy for PDAC was also evaluated. The median PPR among 106 patients who underwent left pancreatectomy was 1.4 (IQR1.1, 1.8). Forty-six had a PPR ≥ 1.5 (median 1.9, IQR1.7, 2.4) and 60 had a PPR < 1.5 (median 1.2, IQR1.0, 1.3). Patients with a PPR ≥ 1.5 had increased median overall survival (OS) compared to patients with a PPR < 1.5 (40 months vs. 20 months, p < 0.001). In multivariate analysis, PPR < 1.5 remained a strong predictor of worse OS (HR 2.24, p = 0.008). Among patients who underwent pancreaticoduodenectomy, the median PPR was 1.1 (IQR1.0, 1.3), which was significantly lower compared to patients who underwent left pancreatectomy (p > 0.001) and did not predict OS.

CONCLUSION

PPR is a biomarker for OS after left pancreatectomy for PDAC. Further studies are warranted to consolidate these findings.

Impact of azole antifungal treatment on outcome in acute invasive fungal rhinosinusitis with orbitocranial involvement: a surgical perspective

PURPOSE

To provide real-life data on azole treatment outcomes and the role of surgery in the current management of invasive fungal rhinosinusitis complicated by orbitocranial fungal infection (OCFI).

METHODS

Data was collected retrospectively from a chart review from four participating centers and a systematic literature review. The study group included patients with OCFI treated with azole antifungals. The control cases were treated with other antifungal agents. The cranial and orbital involvement degree was staged based on the imaging. The extent of the surgical resection was also classified to allow for inter-group comparison.

RESULTS

There were 125 patients in the azole-treated group and 153 in the control group. Among the patients with OCFI cranial extension, 23% were operated on in the azole-treated group and 18% in the control group. However, meninges and brain resection were performed only in the controls (11% of patients) and never in the azole antifungals group. Orbital involvement required surgery in 26% of azole-treated cases and 39% of controls. Despite a more aggressive cranial involvement, azole-treated patients' mortality was significantly lower than in controls, with an OCFI-specific mortality rate of 21% vs. 52%. A similar, though not statistically significant, trend was found for the extent of the orbital disease and surgery.

CONCLUSION

Despite less aggressive surgical intervention for cranial involvement, OCFI patients treated with azoles had a higher survival rate. This finding suggests we may improve morbidity with a more conservative surgical approach in conjunction with azole treatment. The same trend is emerging for orbital involvement.

[UPPER GASTROINTESTINAL BLEEDING CAUSED BY BREAST ANGIOSARCOMA METASTASIS LOCATED IN THE GASTRO-ESOPHAGEAL JUNCTION]

Angiosarcomas are rare and aggressive tumors that originate from endothelial cells and make up roughly 2-3% of all soft-tissue sarcomas. Breast angiosarcomas may be idiopathic or secondary to radiation therapy or chronic lymphatic edema. Primary angiosarcoma of the gastrointestinal (GI) tract is rare and usually causes abdominal pain or GI bleeding. In this case report, we present a patient who appeared with upper gastrointestinal bleeding due to a radiation-induced breast angiosarcoma metastatic lesion in the gastroesophageal junction (GEJ). To the best of our knowledge, breast angiosarcoma metastases to the GEJ were not previously described, and moreover, GI bleeding secondary to breast angiosarcoma GI metastases was not previously reported.

Antibiotics increase aggression behavior and aggression-related pheromones and receptors in Drosophila melanogaster

Aggression is a behavior common in most species; it is controlled by internal and external drivers, including hormones, environmental cues, and social interactions, and underlying pathways are understood in a broad range of species. To date, though, effects of gut microbiota on aggression in the context of gut-brain communication and social behavior have not been completely elucidated. We examine how manipulation of Drosophila melanogaster microbiota affects aggression as well as the pathways that underlie the behavior in this species. Male flies treated with antibiotics exhibited significantly more aggressive behaviors. Furthermore, they had higher levels of cVA and (Z)-9 Tricosene, pheromones associated with aggression in flies, as well as higher expression of the relevant pheromone receptors and transporters OR67d, OR83b, GR32a, and LUSH. These findings suggest that aggressive behavior is, at least in part, mediated by bacterial species in flies.

•

Aggression increases in flies that lack a microbiome

•

Monocolonization with specific bacteria can mediate this effect

•

We observed differences in aggression-related pheromone expression levels

Glucose metabolism: key endogenous regulator of β-cell replication and survival

Recent studies in mice have shown that pancreatic β-cells have a significant potential for regeneration, suggesting that regenerative therapy for diabetes is feasible. Genetic lineage tracing studies indicate that β-cell regeneration is based on the replication of fully differentiated, insulin-positive β-cells. Thus, a major challenge for this field is to identify and enhance the molecular pathways that control β-cell replication and mass. We review evidence, from human genetics and mouse models, that glucose is a major signal for β-cell replication. The mitogenic effect of blood glucose is transmitted via glucose metabolism within β-cells, and through a signalling cascade that resembles the pathway for glucose-stimulated insulin secretion. We introduce the concept that the individual β-cell workload, defined as the amount of insulin that an individual β-cell must secrete to maintain euglycaemia, is the primary determinant of replication, survival and mass. We also propose that a cell-autonomous pathway, similar to that regulating replication, appears to be responsible for at least some of the toxic effects of glucose on β-cells. Understanding and uncoupling the mitogenic and toxic effects of glucose metabolism on β-cells may allow for the development of effective regenerative therapies for diabetes.

Bleeding manifestations in males with von Willebrand disease

von Willebrand disease (vWD) is the most common congenital bleeding disorder in the USA, affecting 1-3% of the population. Previously characterizing the bleeding symptoms in females with type 1 vWD, we evaluated 42 males with type 1 vWD, mean age 16 years (1-64), of whom 24 (57%) presented with bleeding symptoms. The most common initial symptom was postoperative bleeding (26%). The most common bleeding symptoms ever were epistaxis (53%), bruising (50%), postoperative bleeding (47%), haematomas (29%) and oral bleeding (29%). Of postoperative bleeding, ear/nose/throat (44%), dental (17%) and circumcision bleeding (22%) occurred at a median 10 years of age, despite a previous bleeding or family history in 89%. Complications included anaemia in five (12%), neurological sequelae after subdural haematoma and tonsillectomy in two (5%), transfusion-associated hepatitis C in two (5%) and degenerative joint disease after traumatic haemarthroses in one (2%). The bleeding time (BT) was prolonged in 83%, and the ristocetin cofactor (vW:RCoF) and factor VIII (FVIII:C) decreased in 64% and 43%, respectively. Haemarthroses and haematoma formation were associated with a longer activated partial thromboplastin time (APTT) (P < 0.05), and anaemia with a lower FVIII:C (P < 0.05). In 81%, a haemostatic response occurred with 1-8 deamino-d-arginine vasopressin (DDAVP), although, in 13%, surgical intervention was also required to achieve haemostasis. Postoperative bleeding could have been avoided in 89%, if a preoperative past bleeding history or family history had been obtained, and, in at least 94%, if a preoperative BT and APTT had also been performed. The failure to avoid postoperative bleeding and related complications in patients with vWD by taking a personal and family bleeding history constitutes a major public health problem.

A bioactive somatostatin analog without a type II' beta-turn: synthesis and conformational analysis in solution

A cyclic somatostatin analog [structure: see text] (1) has been synthesized. Biological assays show that this compound has strong binding affinities to somatostatin hsst2 and hsst5 receptor subtypes (5.2 and 1.2 nM, respectively, and modest affinity to hsst4 (41.1 nM)). Our conformational analysis carried out in DMSO-d6 indicates that this compound exists as two structures arising from the trans and cis configurations of the peptide bond between Phe7 and N-alkylated Gly8. However, neither conformer exhibits a type II' beta-turn. This is the first report of a potent bioactive somatostatin analog that does not exhibit a type II' beta-turn in solution. Molecular dynamics simulations (500 ps) carried out at 300 K indicate that the backbone of compound 1 is more flexible than other cyclic somatostatin analogs formed by disulfide bonds.

Novel long-acting somatostatin analog with endocrine selectivity: potent suppression of growth hormone but not of insulin

Somatostatin, also known as somatotropin release-inhibiting factor (SRIF), is a natural cyclic peptide inhibitor of pituitary, pancreatic, and gastrointestinal secretion. Its long-acting analogs are in clinical use for treatment of various endocrine syndromes and gastrointestinal anomalies. These analogs are more potent inhibitors of the endocrine release of GH, glucagon, and insulin than the native SRIF; hence, they do not display considerable physiological selectivity. Our goal was to design effective and physiologically selective SRIF analogs with potential therapeutic value. We employed an integrated approach consisting of screening of backbone cyclic peptide libraries constructed on the basis of molecular modeling of known SRIF agonists and of high throughput receptor binding assays with each of the five cloned human SRIF receptors (hsst1-5). By using this approach, we identified a novel, high affinity, enzymatically stable, and long-acting SRIF analog, PTR-3173, which binds with nanomolar affinity to human SRIF receptors hsst2, hsst4, and hsst5. The hsst5 and the rat sst5 (rsst5) forms have the same nanomolar affinity for this analog. In the human carcinoid-derived cell line BON-1, PTR-3173 inhibits forskolin-stimulated cAMP accumulation as efficiently as the drug octreotide, indicating its agonistic effect in this human cell system. In hormone secretion studies with rats, we found that PTR-3173 is 1000-fold and more than 10,000-fold more potent in inhibiting GH release than glucagon and insulin release, respectively. These results suggest that PTR-3173 is the first highly selective somatostatinergic analog for the in vivo inhibition of GH secretion, with minimal or no effect on glucagon and insulin release, respectively.

Experimental acute necrotising pancreatitis: evaluation and characterisation of a model of intraparenchymal injection of sodium taurocholate in rats

OBJECTIVES

To evaluate a simple model that produces progressive dose dependent pancreatitis, by intraparenchymal injection of sodium taurocholate.

DESIGN

Open laboratory study.

SETTING

Teaching hospital, Israel.

MATERIALS

Forty eight Wistar rats.

INTERVENTIONS

Sodium taurocholate was injected, 0.3 ml/100 g body weight, in concentrations of 5% and 10% into the pancreatic parenchyma of 32 Wistar rats, resulting in two distinct groups of severity. In 16 sham controls, saline was injected into the pancreas in similar fashion. Blood samples were withdrawn before, and 6, 24, 48, and 72 hours after induction of pancreatitis.

RESULTS

Six hours after taurocholate injection, there was a sharp increase in the plasma activities of amylase, lipase, and lactate dehydrogenase (LDH). After 24 hours plasma activities of amylase and lipase decreased to near normal values while LDH remained slightly increased for 48 hours and decreased only after 72 hours. At 6 hours after the injection, interleukin-6 (IL-6) concentrations had increased slightly in the 5% group and decreased to the baseline values at 24 hours. In the 10% group, the increase in IL-6 values was significantly greater than in the 5% group (p = 0.04), and correlated well with severity of pancreatitis as defined by histology (p = 0.01) and mortality (p = 0.037). Twenty four hours after injection of taurocholate, morphological changes comprising diffuse necrosis of the pancreas, fat necrosis, and intestinal dilatation secondary to paralytic ileus were severe. Histopathological examination of the pancreas showed good correlation with the clinical findings and with mortality. No morphological changes were detected when saline was injected into the pancreas (sham control), and only mild rises of IL-6, lipase, amylase, and LDH activities were seen at 6 hours after injection. The mortality, after 10 days, was 80% in the 10% taurocholate group, 30% in the 5% taurocholate group, and 0 in the sham control group (p < 0.05).

CONCLUSION

The intraparenchymal injection of taurocholate is easy to perform and highly reproducible. The histopathological injury is dose-dependent, as is the mortality. We conclude that this model is valuable for the study of new treatments for pancreatitis.

Design, synthesis, and biological activities of potent and selective somatostatin analogues incorporating novel peptoid residues

We report the synthesis, bioactivity, and structure-activity relationship studies of compounds related to the Merck cyclic hexapeptide c[Pro6-Phe7-d-Trp8-Lys9-Thr10-Phe11], L-363,301 (the numbering in the sequence refers to the position of the residues in native somatostatin). The Pro residue in this compound is replaced with arylalkyl peptoid residues. We present a novel approach utilizing beta-methyl chiral substitutions to constrain the peptoid side-chain conformation. Our studies led to molecules which show potent binding and increased selectivity to the hsst2 receptor (weaker binding to the hsst3 and hsst5 receptors compared to L-363, 301). In vivo, these peptoid analogues selectively inhibit the release of growth hormone but have no effect on the inhibition of insulin. The biological assays which include binding to five recombinant human somatostatin receptors carried out in two independent laboratories and in vivo inhibition of growth hormone and insulin provide insight into the relationship between structure and biological activity of somatostatin analogues. Our results have important implications for the study of other peptide hormones and neurotransmitters.

A backbone-cyclic, receptor 5-selective somatostatin analogue: synthesis, bioactivity, and nuclear magnetic resonance conformational analysis

Cyclo(PheN2-Tyr-D-Trp-Lys-Val-PheC3)-Thr-NH2 (PTR 3046), a backbone-cyclic somatostatin analogue, was synthesized by solid-phase methodology. The binding characteristics of PTR 3046 to the different somatostatin receptors, expressed in CHO cells, indicate high selectivity to the SSTR5 receptor. PTR 3046 is highly stable against enzymatic degradation as determined in vitro by incubation with rat renal homogenate and human serum. The biological activity of PTR 3046 in vivo was determined in rats. PTR 3046 inhibits bombesin- and caerulein-induced amylase and lipase release from the pancreas without inhibiting growth hormone or glucagon release. The major conformation of PTR 3046 in CD3OH, as determined by NMR, is defined by a type II' beta-turn at D-Trp-Lys and a cis amide bond at Val-PheC3.

Use of Antitranspirants for Control of Powdery Mildew on Field Grown Roses

Antitranspirants Wilt Pruf, Vapor Gard and Folicote protected garden roses from powdery mildew. The coating polymers were stable in the field for about 30 days.

Intracellular trehalase of a hybrid yeast

1. The trehalase found in an extract prepared from a yeast strain that cannot ferment trehalose was studied and characterized. The enzyme is highly specific for trehalose with K(m) 1.02x10(-2)m, and an optimum pH of 6.9. 2. It is inhibited by glucose and by trehalose 6-phosphate, and does not facilitate any significant transglucosylations. 3. pK values 7.7 and 5.8 were detected for the groups associated with binding of the non-ionized substrate to the enzyme. 4. The trehalase was found to be highly labile and was inhibited by thiol-binding reagents. 5. The possible role of this enzyme in the trehalose-dissimilation patterns in the yeast cell was evaluated.