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Assessing the seasonal patterns of the Amazon rainforests has been difficult because of the paucity of ground observations and persistent cloud cover over these forests obscuring optical remote sensing observations. Here, we use data from a new generation of geostationary satellites that carry the Advanced Baseline Imager (ABI) to study the Amazon canopy. ABI is similar to the widely used polar orbiting sensor, the Moderate Resolution Imaging Spectroradiometer (MODIS), but provides observations every 10-15 min. Our analysis of NDVI data collected over the Amazon during 2018-19 shows that ABI provides 21-35 times more cloud-free observations in a month than MODIS. The analyses show statistically significant changes in seasonality over 85% of Amazon forest pixels, an area about three times greater than previously reported using MODIS data. Though additional work is needed in converting the observed changes in seasonality into meaningful changes in canopy dynamics, our results highlight the potential of the new generation geostationary satellites to help us better understand tropical ecosystems, which has been a challenge with only polar orbiting satellites.

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This study highlights the severity of the low snow water equivalent (SWE) and remarkably high temperatures in 2020 in Japan, where reductions in SWE have significant impacts on society due to its importance for water resources. A continuous 60-year land surface simulation forced by reanalysis data revealed that the low SWE in many river basins in the southern snowy region of mainland Japan are the most severe on record. The impact of the remarkably high temperatures in 2020 on the low SWE was investigated by considering the relationships among SWE, temperature, and precipitation. The main difference between the 2020 case and prior periods of low SWE is the record-breaking high temperatures. Despite the fact that SWE was the lowest in 2020, precipitation was much higher than that in 2019, which was one of the lowest SWE on record pre-2020. The results indicate the possibility that even more serious low-SWE periods will be caused if lower precipitation and higher temperatures occur simultaneously.

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We describe our findings on HLH54F, a basic helix-loop-helix transcription factor gene that was highly expressed in the prothoracic gland, an organ producing the insect steroid ecdysone. HLH54F was uncovered by the use of an expressed sequence tag database of the silkworm Bombyx mori. It was also highly expressed in the prothoracic gland of the fruit fly Drosophila melanogaster.

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Based on the continuous observation on the spectral reflectance and CO2 flux during the whole growth period of winter wheat, the correlations between the variations of spectral characteristics and the diurnal CO2 budget of winter wheat field on Loess Plateau were analyzed. The results showed that the spectral reflectance at different wavelengths and the NDVI changed with the growth stages of winter wheat, and the diurnal spectral reflectance changed with solar altitude angle, with the wavelengths at which the reflectance changed most being at 550 nm and 700-1050 nm. At the same time period of different growth stages, the spectral reflectance changed little at 350-670 nm but varied greatly at 700-1050 nm. The red edge position shifted to longer wavelengths at seedling and tillering stages and by the end of wintering while to shorter wavelengths at the beginning of wintering, but the shift to shorter wavelengths was not obvious at ripening stage. No spectrum shift was observed at other growth stages. The diurnal NDVI changed in U-shape, reaching to the minimum at about 13:00 and fluctuating after 16:00, and the change pattern could be fitted by a parabola. Therefore, for winter wheat field, the best time for remote sensing observation should be selected at about 13:00 when the NDVI changed little, except in winter. After the 140th day of seeding, the reflectance and NDVI at 11:00 were symmetrical, and NDVI changed in M-shape, being able to be simulated by a quartic polynomial. There was a significant negative correlation between the NDVI and the diurnal CO2 budget during the whole growth period of winter wheat, but the correlation was weaker around midday.

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Ten-year protocol biopsies were performed in 16 patients treated with calcineurin inhibitor (CNI) continuously. All kidney grafts were functioning well at the time of biopsy with the mean serum creatinine level of 1.6 +/- 0.8 mg/dL. The specimen of biopsy showed various degrees of tissue injury. According to the Banff grading, allograft glomerulopathy (cg) was observed in one case. Interstitial fibrosis (ci) and tubular atrophy (ct) were observed more frequently in 13 (81%) and 15 (93%) cases, respectively. Fibrous intimal thickening (cv) was seen in one (7%) case. Arteriolar hyaline thickening (ah) was seen in 14 (87%) cases. These findings were associated with chronic rejection in one case, recurrence of original disease in four (25%) cases, toxicity of CNI in 14 (87%) cases. Longer follow-up studies are needed to confirm whether CNI should be continued or not in the long-term period following kidney transplantation for better graft survival.

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Twenty-seven living-donor kidney recipients were treated with the antibody against CD25 as the induction immunosuppressive agent. They did not develop acute rejection within 1 month after transplantation, and mean serum creatinine level at 1 month was 1.0 +/- 0.4 mg/dL. There were no findings of acute rejection or drug-induced nephrotoxicity in protocol biopsies at 1 month following transplantation. After 1 month had passed, acute rejection occurred in three cases. The pathological grade of acute rejection varied from borderline to grade III by Banff classification. The careful inspection is necessary to find out the occurrences of acute rejection more than 2 months after transplantation because immunological situation has been changing around this period.

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PURPOSE: Kidney allografts with multiple renal arteries (MRAs) have been used with increasing frequency since the advent of laparoscopic live donor nephrectomy. To determine if MRA grafts affect the short- and long-term outcomes of grafts and patients, we analyzed 340 grafts procured by open nephrectomy. METHODS: We divided the graft recipients into five groups according to the methods used for vascular reconstruction. We compared patient and graft survival, serum creatinine levels, total (rewarm) ischemic times (TIT), incidence of acute tubular necrosis (ATN), need for antihypertensive drugs, incidence of acute rejection episodes, and vascular and urologic complications, between the MRA group and a control group of patients with single-artery renal grafts. RESULTS: In patients who underwent multiple anastomoses in situ, prolonged TIT resulted in an increased incidence of ATN, but there was no significant difference between the MRA groups and the control group (P = 0.45). The incidence of vascular complications was higher in the MRA groups (P < 0.01), but there were no significant differences in the other variables among the groups. CONCLUSION: Multiple renal artery grafts procured by open nephrectomy can be transplanted as successfully as those with single arteries, by using meticulous suturing techniques.

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PURPOSE: We investigated the expression of cyclooxygenase (Cox-1 and Cox-2) in mammary tissues from patients with breast cancer. METHODS: We used reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry. RESULTS: The cancer cells showed very weak expression of Cox-1, but strong expression of immunoreactive Cox-2. In contrast, immunoreactive Cox-2 was very weak in all of the benign mammary tumors examined, including fibroadenoma (FA) and mastopathy (MP). Immunoreactive Cox-1 was also very weak in these benign tumors. The extent and intensity of immunoreactive Cox-2 polypeptides was significantly greater in the cancer cells than in the FA cells or MP cells. RT-PCR analysis showed enhanced expression of Cox-2, but not Cox-1 in breast cancer tissue, and faint expression of Cox-2 in benign tissue. CONCLUSIONS: These results demonstrated that human breast cancer cells generated Cox-2, indicating that Cox-2 might play an important role in the proliferation of breast cancer cells.

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A malignant rhabdoid tumor is very rare and its prognosis is extremely poor. It was first described as a distinctive and highly malignant neoplasm of the infant kidney. Tumors with a similar appearance have been reported in various extrarenal sites. We herein report a case of a 41-year-old man who was admitted to our hospital complaining of a lower abdominal mass. After one series of examinations, the patient underwent a laparotomy. Most such tumors are situated in the mesentery and involve the small intestine, and thus we diagnosed it to originate from mesentery. This tumor could not be resected and only an excisional biopsy was done. It was histologically composed of a solid sheet arrangement with ovoid, round, and lateralized nuclei and mild acidophilic cytoplasm. Inclusion body-like structures were found in the cytoplasm. Immunohistochemically, the tumor cells were positive for cytokeratin, epithelial membrane antigen, vimentin, and CAM5.2. The patient died 2 weeks after operation due to multiple organ failure.

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Twenty-year protocol biopsies were performed in four cases of renal transplant recipients with grafts that had survived 20 years or more. All four recipients received transplants from their parents, and never had episodes of acute rejection. They were maintained with the conventional immunosuppressive protocol including azathioprine, mizoribine, and prednisolone. Three of them had past history of malignant diseases such as breast cancer and tongue cancer. In spite of fair graft function, the microscopic findings of 20-year protocol biopsy showed various degrees of histological damage; e.g. obsolescence of the glomeruli, glomerulosclerosis, arteriole wall thickening, interstitial fibrosis and tubular atrophy. Although two of the four grafts were functioning with low serum creatinine levels (1.3-1.4 mg dL-1) at 24 years and 26 years following transplantation, respectively, the function of the other two grafts had decreased more than 20 years after transplantation. In the two grafts with decreased function, glomerulosclerosis and arteriole wall thickening tended to be more severe (Banff classification of chronic allograft nephropathy [CAN] grade II and III) at the 20-year protocol biopsy compared with the two well-functioning grafts (CAN grade I and II). We conclude that the protocol biopsies even at 20 years can contribute to predict the fate of renal allografts.

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Embryologically, the urachus is the tubular structure that connects the dome of the bladder to the umbilicus. Incomplete obliteration of the urachal lumen results in several anomalies. The most common urachal abnormality is the urachal cyst and, while intraperitoneal rupture of an infected urachal cyst is very rare, acute peritonitis resulting from intraperitoneal rupture is the most dangerous of all complications associated with urachal anomalies. We report the case of an 80-year-old woman who underwent an emergency laparotomy for lower abdominal pain and signs of acute peritonitis, which revealed intraperitoneal rupture of an infected urachal cyst. Infected urachal cysts with intraperitoneal rupture are often misdiagnosed as a common acute abdomen and result in emergency exploratory laparotomy. These patients should be managed by complete excision of the urachal remnant to prevent any malignant change occurring, as malignant changes have been reported.

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