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Integrated genomics and morphological approach reveals interspecific gene flow cases and decodes the origin of selected feathergrasses (Poaceae, Stipa).

Central Asia is a diversity hotspot of arid-adapted grasses from the genus Stipa, with approximately 100 taxa found in the region. Recent studies in the steppe areas of Kazakhstan revealed specimens displaying intermediate morphology, distinguishing them from other taxa that grow sympatrically. Using integrative taxonomy, we investigated whether these individuals resulted from natural speciation or hybridisation, and if so, we would like to know which species were involved in this process feathergrasses. Research conducted in steppes of central Kazakhstan (Kyzylorda region), revealed the existence of individuals morphologically intermediate between S. arabica and S. richteriana, suggesting that these are probably of hybrid origin. Morphology and SNP markers validated the specimens as F1 hybrid between the aforementioned species by cladding separately based on neighbor-joining phylogenetic tree. Moreover, genetic structure displayed a separate cluster and showed almost equal genetic admixture between S. arabica and S. richteriana. Additionally, fastStructure analysis detected two geographically separated cryptic genotypes within S. richteriana population and their involvement in the hybridisation resulted in occurrence of S. × heptapotamica, S. × czerepanovii and S. × korshinskyi which recently were suggested as hybrids. Based on these evidences, we described a new nothospecies S. × kyzylordensis, as F1 hybrid. Furthermore, morphologically, the nothospecies delimited with other hybrids in Kazakh steppe area, marking the first report of hybridisation between S. arabica and S. richteriana, along with molecular evidence for the origin of further species supposed to be hybrids. This finding is crucial to understanding species diversity and hybridisation process in morphologically and genetically distant Stipa species.

Poaceae

Alkaloids of Stipa robusta (sleepygrass) infected with an Acremonium endophyte.

Stipa robusta (= Stipa vaseyi) is a perennial grass found in certain areas of the southwestern United States. It is commonly known as sleepygrass, as horses that ingest this grass may become profoundly somnolent or stuporous for periods of time lasting up to several days. In an attempt to determine the active principle(s), fractionation of a methanolic extract of sleepygrass infected with an Acremonium endophyte has yielded lysergic acid amide (20 micrograms/g dry wt), isolysergic amide (8), 8-hydroxylsergic acid amide (0.3), ergonovine (7), chanoclavine-I (15), and N-formylloline (18). Related alkaloids have been found in many endophyte-infected grasses. The dominant alkaloid constituent in sleepygrass, lysergic acid amide, has not previously been identified in a grass in such high concentration. Lysergic acid amide is likely to be the basis for the extreme sedative effects on animals, given past pharmacological work on the compound from the ergot fungus Claviceps paspali.

Acremonium

Extrinsic allergic alveolitis caused by esparto (Stipa tenacissima).

Extrinsic allergic alveolitis (EAA) are clinical entities of growing importance. The discovered etiological agents which can induce them, organic and inorganic substances of low molecular weight which are frequently found in the laboral environment, are every day more numerous. In the group of substances which are rarely implied in EAA etiology, we must mention esparto (Stipa tenacissima), a grass of the graminea family widely used in Spain. The EAA caused by Stipa tenacissima inhalation in known as stipatosis, a disease with poorly systematized clinical manifestations because of the few cases described in the literature so far. Our purpose in this report is to show the second case, in world literature, of EAA correctly characterized.

Adult

Extraperitoneal aortic bypass with exclusion of the intact infra-renal aortic aneurysm: the in-situ management of aortic aneurysms. A preliminary report.

Transabdominal aortic aneurysmorraphy with graft replacement is the generally accepted and most widely applied surgical approach in the treatment of infra-renal abdominal aortic aneurysm with a mortality rate of 2-5%. The alternative, retroperitoneal exposure of the aorta, although utilized for the first reported repair of an AAA by Dubost and championed by Rob, Stipa and Shaw, Helsby and Moosa and more recently by Williams et al., offers superior exposure and decreased post-operative morbidity. Despite these advantages, it is not commonly used by most vascular surgeons for the surgical management of aortic aneurysms. We have treated 35 patients using an extended retroperitoneal approach in which the aneurysm was treated by division of the infra-renal aorta, an end-to-end proximal anastomosis with an aortic bypass, and over-sewing of the aneurysm. In this group of patients, we found less post-operative physiological disturbances and a reduced requirement for blood transfusion. These data suggest that this method of retroperitoneal exclusion and bypass is generally applicable and is of particular value in the obese and/or the higher risk, medically disadvantaged patient.

Aged

Local recurrence after curative resection for colorectal cancer: frequency, risk factors and treatment.

Analysis of 498 patients with colorectal carcinoma was retrospectively reviewed to evaluate the incidence, risk factors and therapy of local recurrent carcinoma following curative resection. Complete follow-up information was obtained in all but four patients (99.2%). After a median follow up of 42 months, 64 out of 469 (13.6%) patients developed local recurrence (LR). The incidence of LR was higher in rectal than in colon cancer patients (18.3% vs 8.9%) (P less than 0.005). Separate univariate and Cox analyses for rectal patients showed tumor site (P less than 0.02). Dukes stage (P less than 0.002), and adjuvant radiotherapy (P = 0.05) determined risk of LR. For colon cancer patients risk of LR was determined by histological tumor grade (P less than 0.01). Out of 64 patients, 5 (7.8%) underwent radical excision of LR. Forty percent of these survived at 5-year (P less than 0.08). Palliative treatment (radio-chemotherapy) obtained a 5-year survival of 15.3%, with no survivors in no-treatment group. These results suggest that local recurrent colorectal carcinoma remain a difficult treatment problem. More effective combinations of surgery and adjuvant therapy are therefore mandatory to reduce the incidence of local failure in high risk colorectal patients.

Adenocarcinoma

[Laparoscopic cholecystectomy. The beginning of a new era].

An important breakthrough in the field of general surgery, laparoscopic cholecystectomy (LC) offers significant advantages for patients. Major reasons for the rapid worldwide acceptance of this new surgical procedure is that patients experience reduced postoperative pain, ileus is virtually abolished, and the patient is able to leave the hospital the following day without a major abdominal scar. This appears to respond to patients' desire for less invasive approaches to the treatment of gallstone disease. LC is thus becoming the treatment of choice for symptomatic gallbladder disease. Its rapidly growing popularity is evident in Italy where many centers are offering LC routinely, in alternative to open cholecystectomy. A critical appraisal of this new technology is necessary, in light of recent data from centers presenting results and complications of large series of LCs. Adequate training of surgeons who will perform LC is also becoming a major concern. In this review the authors describe patient evaluation and selection for LC. Effective therapeutic strategies are illustrated, including the central, but nevertheless controversial role of endoscopic retrograde cholangiopancreatography (ERCP) as an approach to common bile duct lithiasis. Currently, LC should be performed in centers with the availability of an endoscopist with expertise in ERCP. Following the success of LC, other minimally invasive techniques will evolve in various surgical specialties. New generations of surgeons will thus have to familiarize with these emerging techniques while maintaining a critical attitude of evaluation.

Cholecystectomy

[Biologic response modifiers in the treatment of solid tumors].

This study concerns the clinical applications in Oncology of Biologic Response Modifiers; the authors focus the results reached in neoplasms, such as renal cell carcinoma or melanoma, whose sensitivity to this treatment has been proved. Prospective studies, published in 1990 have been reviewed, considering only those in which route and rate of response (complete and partial) were clearly specified. At present clinical efficacy concerning this topic is controversial and it probably depends on different reasons: immunogenicity of cancer, variable route of administration, lack of predictors. It should be stressed that more in depth studies about cancer immunology are required; a wide spread of immunotherapy will be feasible only by improving therapeutic strategies and limiting adverse effects of this treatment.

Adjuvants, Immunologic

[Indications and limitations of the surgical treatment of portal hypertension].

The authors report a review of the literature and describe their personal experience with treating esophageal varices; all types of surgical approaches (selective and total shunts, esophageal transection) are examined and compared to the results obtained with non surgical treatment (particularly endoscopic sclerotherapy). Indications and results of surgical treatment are discussed from three definitive viewpoints: prevention of first bleeding or prophylactic treatment, control of acute bleeding or emergency treatment and prevention of rebleeding or elective treatment.

Esophageal and Gastric Varices

Pylorus-preserving total pancreatectomy and segmental pancreas autotransplantation.

12 patients affected by periampullary neoplasms underwent surgery consisting of modified pylorus-preserving total pancreatectomy. In 8 of these patients, a segmental pancreas autotransplantation was performed by anastomosing the splenic to the femoral vessels in the Scarpa's triangle. The pancreas was treated by irradiation to inhibit the exocrine function. Gastric emptying was studied in 9 survivors by upper gastrointestinal barium series. In 6 patients gastric emptying and pyloric function were also evaluated by radionuclide studies. In 3 patients the transplanted pancreas had to be removed within the second postoperative week because of graft thrombosis, infection or hemorrhage. In a mean follow-up of 16 months (range: 6-20 months) the remaining 5 transplants showed a good endocrine activity until the beginning of antiblastic treatment for hepatic metastasis (3 cases), pancreatic fibrosis (1 case) or the patient's death (2 case). At present no graft is still functioning.

Adult

Prognostic significance of flow cytometry in lung cancer. A 5-year study.

Flow cytometrically determined cellular DNA content has been measured on specimens from 101 patients affected by lung cancer (40 epidermoid cell carcinoma, 22 adenocarcinoma, 21 large cell carcinoma, 11 small cell carcinoma, and seven undifferentiated carcinoma), and one by mesothelioma. Ninety-eight of 102 (96%) patients with neoplastic disease evidenced the occurrence of at least one cytometrically aneuploid cell subpopulation. Fifty-five of 102 (54%) cases evidenced the occurrence of multiclonality, that is, the presence of more than one aneuploid stem cell line. However, the incidence of multiclonality in lung carcinoma was statistically different in surgical cases (where multiple site sampling from the primary and lymph nodes was possible) in comparison to the nonsurgical ones (e.g., bronchial washing): 48/77 (62%) and six of 24 (25%), respectively. Therefore, only the 77 surgical patients were used for further analysis. The cases were classified according to the DNA index (DI) in the following way: Group A (tumors with one or more stem lines with DI ranging from 1 to 2) and Group B (tumors with at least one stem line with DI less than 1 or greater than 2). A significant correlation has been found between the cytometric ploidy condition so defined (Groups A and B) and the tumor mass doubling time (DT), Group B being associated with fast growing tumors (DT lower than 90 days). A statistically better 12-month survival rate (5-year maximum follow-up) was observed in Group A (88%) in respect to Group B (47%) and is evident in the patient survival time course. A better prognostic indication can be achieved by stratifying the patients according to both the cytometric ploidy condition and the tumor DT. Flow cytometric data can usefully contribute to the prognostic assessment of lung carcinoma provided that representative cellular material is collected by multiple site sampling.

Actuarial Analysis

Portal hypertension treated by left gastro-epiploic to left renal vein anastomosis: case report.

A case of portal hypertension is presented in which because of the presence of multiple thromboses of the main portal branches one of the usual portasystemic shunts could not be performed. An anastomosis between an enlarged left gastro-epiploc vein and the left renal vein was successfully carried out. Six months after surgery the patient was well and no further haemorrhage had occured.

Female

Flow cytometric analysis in colorectal carcinoma: prognostic significance of cellular DNA content.

The prognostic value of DNA ploidy status was evaluated prospectively in 70 patients with colorectal carcinoma. Cellular DNA content was measured by flow cytometry from fresh specimens with multiple site sampling. Seventy-five percent of cases exhibited a DNA aneuploid pattern. In a univariate analysis, DNA ploidy status showed a statistically significant correlation with survival (p less than 0.05), weaker than Dukes' stage (p less than 0.001). No correlation was observed between survival and presence of multiple DNA stemlines. In a multivariate analysis, Dukes' stage was the strongest prognostic indicator (p = 0.01) while DNA ploidy status did not show an independent prognostic value. It is concluded that DNA ploidy status is associated with pathological features of aggressive malignancy, but it does not have a determinant role in predicting survival.

Adenocarcinoma