Change in structural morphology on addition of ZnO and its effect on fluorescence of Yb³âº/Er³âº doped Y2O3.

Yb(3+)/Er(3+) codoped Y(2)O(3) phosphor and its composite with ZnO have been synthesized by combustion method. Morphology of the materials has been investigated using X-ray diffraction pattern (XRD) and scanning electron microscopy (SEM) techniques. XRD confirms the constituents as Y(2)O(3) and ZnO, with average crystallite size of 112 nm. On addition of ZnO, a small shifting in XRD pattern of Y(2)O(3) is observed. SEM pattern suggests that the average particle size lies in micro-range (0.5 µm). A dumble like structure is observed for hybrid material on annealing at 1473 K. A strong green (525, 546 nm) with weak blue (411 nm) and red (657 nm) emissions through upconversion has been observed from the phosphor on excitation with 976 nm diode laser. The observed emissions involve (2)H(9/2)→(4)I(15/2), (2)H(11/2)→(4)I(15/2), (4)S(3/2)→(4)I(15/2) and (4)F(9/2)→(4)I(15/2) electronic transitions, respectively. The upconversion process has been confirmed by power dependence measurements and its slope value was found to be 1.85, 1.72 for green and red emissions, respectively. On addition of ZnO, the intensity of these emissions is enhanced several times. The reason behind the enhancement is discussed with the help of the emitting level lifetime. An interesting dual mode property (upconversion and downconversion) to the same material has been observed on excitation with 532 nm laser source.

Graft repair: the treatment of choice for renal allograft rupture.

The incidence of renal allograft rupture among 237 live donor renal transplant patients was 6.3%. The most common association was with acute rejection. The graft salvage rate was 73% and the longest graft function was 10 years.

Tuberculous pyomyositis in a renal transplant recipient.

Infections are a major cause of morbidity and mortality in renal transplant recipients. Although these patients are susceptible to many types of infection, soft tissue infections are rare. We report a case of tuberculous pyomyositis involving the left erector spinae muscle but with no other manifestations of tuberculosis. The diagnosis was suspected from the CT scan appearance and confirmed by microscopy and culture of the pus. Surgical incision and drainage, together with antituberculosis therapy, cured the infection. The relevant literature is briefly reviewed.

Psychological assessment of blood related renal donors.

The impact of kidney donation on the psychological health of 31 living related donors was assessed by administering certain psychological tests before and after the operation (for donating the kidney). The results indicated a significant rise in the somatization subscale of the Middlesex Hospital Questionnaire (MHQ) from a mean of 1.61 to 3.23. There was no significant change in the other variables of these instruments or in the locus of control score. Only about one-fourth of the donors had prior knowledge of renal transplant. In almost all cases, the decision to donate had been voluntary and immediate, motivated by a concern for the recipient; there was virtually no second thoughts or regrets subsequently, which was apparently partly related to the opinions of other relatives who positively valued the act of donation.

Sigmoid colon conduit urinary diversion in a renal transplant recipient.

Renal allotransplantation is the treatment of choice for patients with end-stage renal disease (ESRD). With increasing technical expertise, it has been realised that presence of a normal lower urinary tract is not a necessity for transplantation. Advanced genito-urinary tuberculosis frequently leads to a small-capacity bladder. Herein, we present a case of ESRD due to urinary tuberculosis in whom sigmoid colon conduit urinary diversion was carried out. The immunosuppressed status did not increase the complications of a sigmoid colon conduit urinary diversion.

Gastro-intestinal injuries in abdominal trauma.

Management of 55 patients of gastro-intestinal injuries has been reviewed. Eighty percent of the patients presented with generalised peritonitis and jejunum was the commonest segment of the bowel injured. Pneumoperitoneum co-related poorly with intestinal disruption. It was present in 35.8 per cent of the cases. Repeated physical examination was found to be paramount importance. Sixty percent of the patients has associated intra-extra-abdominal injuries. Preoperative shock, multiple hollow visceral injury, septicemia, and location of injury (colon and duodenum) were significant prognostic factors associated with the high mortality. Mortality in the series was 25.4 per cent.

Acute colitis in renal transplant recipients.

Gastrointestinal complications constitute an important cause of morbidity and mortality in renal transplant recipients. The present communication is based on our experience with 10 living related donor kidney transplant recipients who suffered from severe acute colitis in the posttransplant period. A specific etiological factor was detected in only one (atypical mycobacteria). Six patients succumbed to the illness in the acute stage, thus highlighting its seriousness. Various factors involved in etiology have been discussed, and early therapeutic intervention emphasized.

Brain abscess due to Nocardia.

Cerebral Nocardiosis is a rare disease, usually occurring in immunocompromised hosts. We report here two cases of brain abscess due to Nocardia species-one due to usual N. asteroides and other by uncommon N. caviae. N. asteroides affected the brain in a post renal transplant patient, whereas N. caviae caused infection of brain in an apparently healthy individual. To the best of our knowledge, all the previous cases of brain abscess due to Nocardia caviae have been reported in compromised hosts. Agar dilution antimicrobial testing showed relatively higher resistant pattern in N. asteroides. In spite of antimicrobial therapy, both the patients succumbed, one within 4 days and other after an initial improvement for four weeks due to drainage of abscess.

Benign disease of the common bile duct.

The incidence of common bile duct (CBD) pathology in a group of patients with benign biliary disease (n = 505) was found to be 23.2 per cent. The spectrum included 111 patients (90.2 per cent) with CBD stones, 37 of whom (33.3 per cent) had no symptoms or findings pre-operatively indicating CBD involvement. Five patients had papillary stenosis, three had postoperative CBD strictures, one had a choledochal cyst and one had an external biliary fistula. Of the 100 CBDs measuring more than 10 mm in diameter, 90 harboured calculi. In the remaining 23 CBDs measuring less than 10 mm, calculi were present in 21. The presence of CBD calculi was demonstrated by intra-operative cholangiography in 49 patients. In the remaining patients (n = 74), the diagnosis of CBD pathology was made either by percutaneous transhepatic cholangiography, endoscopic retrograde cholangio-pancreatography, T-tube cholangiography or peroperative palpation. The surgical procedures performed included choledochotomy and T-tube drainage (n = 74), transduodenal sphincteroplasty (n = 27) and choledochoduodenostomy (n = 18). The overall mortality and morbidity of CBD exploration was 3.3 per cent and 24.4 per cent respectively, which was significantly greater than that for cholecystectomy alone (0.3 per cent and 8.6 per cent respectively). Transduodenal sphincteroplasty carried a much higher mortality (11 per cent) and morbidity (52 per cent) when compared with other procedures.

Cyclophosphamide in renal transplantation.

Success in renal transplantation is now largely dependent on safe and effective immunosuppression. Nonspecific immunosuppression by chemical agents continues to be the mainstay of clinical immunosuppression. Azathioprine and prednisolone have remained the two main drugs used in combination in standard immunosuppressive therapy in renal transplantation for many years. Although cyclophosphamide (CP) was tried in the early years of transplantation, enthusiasm for its use was dampened by the advent of newer agents. We have analyzed our experience with 29 recipients of living-related donor (LRD) renal allotransplantation on cyclophosphamide therapy. Cyclophosphamide is a safe and effective alternative to azathioprine in clinical renal allotransplantation. Due to its easy availability and the fact that it is a cheaper alternative to azathioprine and cyclosporine, it is more significant for developing countries.

Renal allograft rupture and its management.

Renal allograft rupture, although a rare complication, was encountered in 11 of our 137 cases of live kidney donor transplants. The commonest finding was an associated acute rejection. Our cases were mainly given conservative treatment with repair of the rupture and antirejection therapy. Eight of our kidneys were saved in this way, thus eight of the 11 patients survived. None of the deaths were related to the graft rupture or its effects.