Differences between Pygmy and Non-Pygmy Hunting in Congo Basin Forests.

We use data on game harvest from 60 Pygmy and non-Pygmy settlements in the Congo Basin forests to examine whether hunting patterns and prey profiles differ between the two hunter groups. For each group, we calculate hunted animal numbers and biomass available per inhabitant, P, per year (harvest rates) and killed per hunter, H, per year (extraction rates). We assess the impact of hunting of both hunter groups from estimates of numbers and biomass of prey species killed per square kilometre, and by examining the proportion of hunted taxa of low, medium and high population growth rates as a measure of their vulnerability to overhunting. We then map harvested biomass (kg-1P-1Yr-1) of bushmeat by Pygmies and non-Pygmies throughout the Congo Basin. Hunting patterns differ between Pygmies and non-Pygmies; Pygmies take larger and different prey and non-Pygmies sell more for profit. We show that non-Pygmies have a potentially more severe impact on prey populations than Pygmies. This is because non-Pygmies hunt a wider range of species, and twice as many animals are taken per square kilometre. Moreover, in non-Pygmy settlements there was a larger proportion of game taken of low population growth rate. Our harvest map shows that the non-Pygmy population may be responsible for 27 times more animals harvested than the Pygmy population. Such differences indicate that the intense competition that may arise from the more widespread commercial hunting by non-Pygmies is a far more important constraint and source of conflict than are protected areas.

Te concentration dependent photoemission and inverse-photoemission study of FeSe1-xTex.

We have characterized the electronic structure of FeSe1-x Te x for various x values using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasing x. HRPES exhibits systematic x dependence of the structure near the Fermi level (EF): its splitting near EF and filling of the pseudogap in FeSe. IPES shows two features, near EF and approximately 6 eV above EF; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states near EF for FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe.

Unilateral versus bilateral endoscopic metal stenting for malignant hilar biliary obstruction.

BACKGROUND AND AIM: The extent of liver drainage for palliative treatment of malignant hilar biliary obstruction is controversial. The aim of this study was to compare endoscopic unilateral versus bilateral drainage in patients with malignant hilar biliary obstruction using a self-expanding metal stent (SEMS). METHODS: We carried out a retrospective review of 46 consecutive patients with malignant hilar biliary obstruction who were treated by endoscopic biliary drainage using SEMS between 1997 and 2005. Unilateral metal stenting (group A) was performed in 17 patients between 1997 and 2000, and bilateral metal stenting (group B) was performed in 29 patients between 2001 and 2005. The successful stent insertion, successful drainage, early complications, late complications, stent patency, and survival rate for groups A and B were evaluated and compared retrospectively. RESULTS: There were no significant differences between the two groups in successful stent insertion (100% vs 90%, group A vs B, respectively), successful drainage (100% vs 96%), early complications (0% vs 10%), or late complications (65% vs 54%). Cumulative stent patency was significantly better in group B than in group A (P = 0.009). In cases of cholangiocarcinoma, cumulative stent patency was significantly better in group B than in group A (P = 0.009), whereas there were no inter-group differences for gallbladder carcinoma. Cumulative survival did not differ significantly between the groups. CONCLUSIONS: Endoscopic bilateral drainage using SEMS for malignant hilar biliary obstruction is more effective than unilateral drainage in terms of cumulative stent patency, especially in cases of cholangiocarcinoma.

Rupture of hepatic aneurysm complicating hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu disease) for which hepatic arterial coil embolization was effective.

A 74-year-old woman was transferred to our hospital for further examinations because of abdominal fullness and abnormal levels of serum liver/biliary enzyme persisting for 3 weeks. She had anemia and dilatation of many capillary vessels in her fingers, palms, and tongue in addition to reporting frequent incidences of nasal bleeding in herself and her family. Abdominal ultrasonography detected a cystic lesion in the right hepatic lobe, connected to a dilated tortuous hepatic artery. A low-echoic hepatic phyma was also detected in the back of the cystic lesion. Abdominal computed tomography and magnetic resonance imaging indicated that the cystic lesion was an aneurysm and the low-echoic phyma was a hematoma. Hepatic arteriography confirmed a hepatic aneurysm, tortuous dilatation of the hepatic artery, and the complication of an arteriovenous shunt in the liver. Taking all of these findings into consideration, this case was diagnosed as hereditary hemorrhagic telangiectasia (HTT) complicated by a hepatic aneurysm causing intrahepatic hematoma. To prevent re-rupture of the aneurysm, we performed a hepatic arterial coil embolization. After therapy, no blood flow to the aneurysm was detected by ultrasonic color Doppler method and the hematoma gradually diminished. There have been no reports of a case in which hepatic arterial embolization was effective for HHT-associated hepatic aneurysm causing intrahepatic hematoma. This very rare case provides important clinical information regarding abdominal vascular complications of HTT and a less invasive treatment for them.

Usefulness of transpapillary bile duct brushing cytology and forceps biopsy for improved diagnosis in patients with biliary strictures.

BACKGROUND AND AIM: Transpapillary bile duct brushing cytology and/or forceps biopsy was performed in the presence of an indwelling guidewire in patients with biliary stricture, and the treatment time, overall diagnosis rate, diagnosis rate of each disease, complications, and influences on subsequent biliary drainage were investigated. METHODS: After endoscopic retrograde cholangiography, brushing cytology was performed, followed by forceps biopsy. In patients with obstructive jaundice, endoscopic biliary drainage (EBD) was subsequently performed. To investigate the influences of bile duct brushing cytology and forceps biopsy on EBD, patients who underwent subsequent EBD by plastic stent were compared with patients who underwent EBD alone. RESULTS: The samples for cytology were collected successfully in all cases, and the sensitivity for malignancy/benignity, specificity, and accuracy were 71.6%, 100%, and 75.0%, respectively. The biopsy sampling was successful in 51 patients, and samples applicable to the evaluation were collected in all 51 patients. The sensitivity for malignancy/benignity, specificity, and accuracy were 65.2%, 100%, and 68.6%, respectively. Combination of the two procedures increased the sensitivity and accuracy to 73.5% and 76.6%, respectively. The time required for cytology and biopsy was 11.7 min, which is relatively short. Cytology and biopsy did not affect drainage. Regarding accidents, bile duct perforation occurred during biopsy in one patient (1.9%), but was rapidly improved by endoscopic biliary drainage. CONCLUSIONS: Transpapillary brushing cytology and forceps biopsy could be performed in a short time. The diagnosis rate was high, and the incidence of complication was low, having no influence on subsequent biliary drainage.

[Clinical evaluation of covered self-expandable metallic stent for unresectable malignant stomach pyloric region and duodenal obstruction].

We evaluated palliative treatment for unresectable malignant stomach pyloric region and the duodenal obstruction using covered self-expandable metallic stent (SEMS). Fifty-seven patients (26 stomach pyloric stenosis, 31 duodenal stenosis) were underwent palliative treatment using covered SEMS. The covered SEMS was Ultraflex stent for esophageal obstruction. The covered SEMS was successfully indwelled in the target region in 56 patients. The patients became able to ingest orally after a mean of 2 days, and 96% of the patients (54/56) became able to eat solid or semi-solid diets later. The SEMS obstruction by tumor ingrowth or hyperplasia was not occurred, so SEMS was maintenance-free. We concluded covered SEMS was useful palliative treatment because it prevented SEMS obstruction by tumor ingrowth or hyperplasia and it was maintenance-free.

Intracystic hemorrhage of a simple liver cyst mimicking a biliary cystadenocarcinoma.

Simple liver cysts are rarely complicated by intracystic hemorrhage. We encountered a case of simple liver cyst that was morphologically similar to biliary cystadenocarcinoma, which was complicated by asymptomatic intracystic hemorrhage and successfully treated by right lobectomy. A large cystic lesion of the liver was detected in a 57-year-old woman during a mass screening health check. Abdominal ultrasonography (US) revealed that the cystic lesion, containing many hyperechoic papillary structures, occupied almost the entire region of the right hepatic lobe. In addition, a round mural nodule, measuring approximately 5 cm in diameter, was detected in the cystic wall. Abdominal computed tomography (CT) revealed that the inner part of the cystic lesion showed homogeneous low density, but CT did not show the round nodule detected by US. On T1-weighted sequence of magnetic resonance imaging (MRI), the lesion showed homogeneous high signals, together with a low-signal tumorous lesion in the cystic wall. T2-weighted sequence of MRI showed unhomogeneous high signals, together with high signals in the tumorous part. These findings did not exclude the possibility of a malignant cystic tumor, such as biliary cystadenocarcinoma. Therefore, right lobectomy was performed. Histological examinations of resected tissue specimens revealed that the lesion was a liver cyst containing a large amount of blood clot, and that the tumorous lesion detected by US and MRI was a large mass of blood clot which was partly liquefied. This case indicates the diagnostic importance of the morphological discordance between CT and US or MRI findings for liver cyst containing a large amount of blood clot.

Exophytic pedunculated gastrointestinal stromal tumor with remarkable cystic change.

A 59-year-old man with bloody stools, and previously diagnosed with sigmoid colon carcinoma, visited our hospital. Preoperative abdominal ultrasonography (US) showed another tumor, with an uneven irregular surface, measuring about 9 x 5 cm, below the left hypochondrium. The tumor consisted of several cysts. Abdominal computed tomography (CT) showed a multicystic tumor attached to the stomach, and its septum and marginal region were intensely stained on contrast imaging. On magnetic resonance imaging (MRI), low and markedly high signals were revealed in the tumor on T1-weighted and T2-weighted sequences, respectively. Contrast imaging of the upper digestive tract showed extramural compression of the greater curvature of the antral stomach by the tumor. The tumor was partially imaged by endoscopic ultrasonography (EUS), but continuity to the stomach was not confirmed. On abdominal angiography, the tumor was slightly stained via the gastroepiploic arteries. Surgical treatment was performed to excise both the gastric tumor and the sigmoid colon carcinoma. The gastric tumor was removed with gastric wall tissue where the tumor was attached to a 2-cm pedicle. It was multicystic, contained watery fluid, and had a smooth outer surface. Histologically, the tumor consisted of multiple irregular cysts without epithelial lining, and solid epitheloid cell nests in between. The tumor cells had clear or eosinophilic cytoplasm and round nuclei. No mitotic figures were seen. The tumor cells in the pedicle were connected with the muscularis propriae of the stomach. Immunohistochemistry showed c-kit-positive, CD34-positive smooth muscle actin (SMA)-negative, and S-100-negative staining of tumor cells. The final diagnosis was gastrointestinal stromal tumor (GIST).