Management of iatrogenic facial nerve palsy and labyrinthine fistula in mastoid surgery

A 6-year review of complications of mastoid surgery between June 1995 and June 2001 revealed five cases with serious iatrogenic complications from mastoid surgery, of which four were facial nerve palsy and two were labyrinthine fistula. One of these patients had concomitant facial nerve palsy and labyrinthine fistula. There were two cases of complete facial nerve palsy (House Brackmann grade VI) and two cases of incomplete palsy (House Brackmann grades IV and V). The second genu was the site of injury in three of the four cases. Of the four cases with facial nerve palsy, two patients had full recovery (House Brackmann grade I), one recovered only to House Brackmann grade III, and one was lost to follow-up. Both patients with labyrinthine fistula had postoperative vertigo and profound sensorineural hearing loss. The site of iatrogenic fenestration was the lateral semicircular canal in both cases.     

Pelvic spleen with uterovaginal prolapse

A case of wandering (pelvic) spleen associated with third degree uterovaginal prolapse and ascaris in the biliary and intestinal tract is being presented here. On laparotomy; congested splenomegaly was found in the pelvis. Splenectomy, total abdominal hysterectomy and bilateral salpingo-ophrectomy was performed.     

Nephrotic proteinuria associated with high-dose pamidronate in multiple myeloma

Five patients receiving increased dose or frequency of pamidronate beyond the recommended dose (90 mg/monthly) exhibited nephrotic proteinuria (range 3.96-24 g/24 h). On dose reduction or discontinuation, three of these patients showed decreased proteinuria to normal levels (< 1 g/24 h), and proteinuria decreased to 4.5 g/24 h from a peak of 24 g/24 h in one patient. One patient on haemodialysis (hence not evaluable) had proteinuria of 2 g/24 h and elevated creatinine levels. One other patient continued to show elevated creatinine levels (272.8 micro mol/l). Renal biopsies obtained in two patients revealed focal segmental glomerulosclerosis.     

Cutaneous manifestations of cancer

The appearance of skin lesions in patients with occult or obvious malignancy may be of extreme value in the detection and management of cancer because the skin is readily accessible to examination and biopsy. Examination of the skin of our patients can provide important insights into underlying malignant processes or possible complications from cancer treatment. The range of cutaneous abnormalities is wide, and include cutaneous paraneoplastic syndromes such as xanthomas, acanthosis nigricans, carcinoid syndrome, unusual erythematous eruptions such as erythema gyratum repens, and a number of genetic syndromes associated with malignancies and inherited dermatoses.     

Hip displacement in Wolf–Hirschhorn syndrome: Report on three cases and review of associated musculoskeletal pathologies

Wolf–Hirschhorn syndrome is a rare genetic disease caused by a chromosomal deletion of the distal short arm of Chromosome 4. It is associated with multisystem abnormalities, including delayed growth, characteristic facial features, epilepsy, and skeletal abnormalities. We report three patients who developed hip displacement, and describe the occurrence of delayed and nonunion in patients who underwent corrective proximal femoral osteotomy for hip displacement. We also performed a literature review identifying common musculoskeletal presentations associated with the condition. Patients with Wolf–Hirschhorn Syndrome are at risk of hip displacement (subluxation), and we would advocate annual hip surveillance in this patient group.     

Mutation of the p53 tumour suppressor gene occurs preferentially in the chromophobe type of renal cell tumour

Genomic DNA from 30 non-papillary and 20 chromophobe renal cell carcinomas (RCCs), 30 papillary renal cell tumours, and 20 renal oncocytomas was screened for the presence of mutations in exons 5–8 of the p53 tumour suppressor gene by polymerase chain reaction–single strand conformation polymorphism analysis and direct DNA sequencing. Mutations leading to an amino acid change were found only in 6 out of 20 chromophobe RCCs. Microsatellite analysis of chromophobe RCCs revealed the loss of one allele at chromosome 17p in 14 out of 18 informative cases. No mutation of the p53 gene was found in five sarcomatous RCCs or in seven tumours of stage IV. This study shows that mutation of the p53 tumour suppressor gene does not correlate with the specific loss of DNA sequences at chromosome 17 in chromophobe RCCs, nor can it be used as a prognostic parameter for RCCs in general. © 1997 John Wiley & Sons, Ltd.     

Efficient tuning of zinc phthalocyanine-based dyes for dye-sensitized solar cells: a detailed DFT study

The growing energy demand speed up the designing of competent photovoltaic materials. Herein, five zinc phthalocyanine-based donor materials T1–T5 are designed by substituting various groups (isopropoxy, cyano, fluoro, methoxycarbonyl, and dicyanomethyl) around zinc phthalocyanine. B3LYP/6-31G (d,p) level density functional theory (DFT) was used to investigate the optoelectronic properties of five zinc phthalocyanine-based dyes T1–T5 for dye-sensitized solar cells. The designed molecule T1 shows maximum absorption wavelength (λ_max) in the absorption spectrum at 708.89 and 751.88 nm both in gaseous state and in THF (tetrahydrofuran) solvent. The E_g value of T1 (1.86 eV) is less than reference R, indicating a greater charge transfer rate for T1 among the molecules. The values of open-circuit voltages achieved with acceptor polymer PC₇₁BM are higher than R except for T1 and are 0.69 V, 1.95 V, 1.20 V, 1.44 V, and 1.84 V for T1, T2, T3, T4, and T5, respectively. The lower the reorganization energy, the higher the charge transfer for T1 due to its lower hole mobility (0.06297 eV) than R. Thus, the designed T1–T5 molecules are expected to exhibit superior performance in dye-sensitized solar cells.

We used a quantum chemical approach to investigate the optoelectronic properties of dyes T1–T5 for dye-sensitized solar cells using DFT and TD-DFT computation. The newly designed molecules exhibited outstanding photovoltaic and optoelectronic properties.     

Molecular analysis of the cyclin-dependent kinase inhibitor genes p15INK4b/MTS21, p16INK4/MTS1, p18 and pl9 in human cancer cell lines

Cyclin-dependent kinase-4 inhibitor genes (INK4) regulate the cell cycle and are candidate tumor-suppressor genes. To determine if alterations in the coding regions of the pl8 and pl9 genes, which are novel members of the INK4 family and if they correlate with the development of human cancer, 100 human cancer cell lines were analyzed. Two other INK4 gene family members, p15^INK4b/MTS2 and pl6^INK4/MTS1 genes were also analyzed. Homozygous deletions of the p15^INK4b/MTS2 gene were detected in 29 cancer cell lines. Thirty-five homozygous deletions and 7 intragenic mutations of the pl6^INK4/MTS1 gene were also detected in these cell lines. Neither homozygous deletions nor intragenic mutations of the p18 and p19 genes were found except in an ovarian cancer cell line, SKOV3, harboring a single base pair deletion in exon 1 of p19. In p16^INK4/MTS1 expression analysis, 5 cell lines with both authentic and alternative spliced pl6^INK4/MTS1 mRNA had no detectable pl6^INK4/MTS1 protein. These results suggest the hypotheses that either post-translational modification or enhanced degradation may be responsible for the lack of detection of the pl6^INK4/MTS1 protein. Using Western blot analysis, subsets of 26 human cancer cell lines were examined for pl8 expression and 39 cell lines for p19 expression. All of these cell lines expressed the pl8 or pl9 protein, with the exception of SKOV3, which did not express pl9. Therefore, the INK4 gene family may be divided into 2 groups. One group includes p15^INK4b/MTS2 and pl6^INK4/MTS1 in which genetic and epigenetic alterations might contribute to the development of human cancers. The other group includes p18 and p19, in which somatic mutations are uncommon in many types of human cancer, and their role in human carcinogenesis and cancer progression is uncertain. (This article is a US Government work and, as such, is in the public domain in the United States of America.) © 1996 Wiley-Liss, Inc.     

Backside wear of polyethylene tibial inserts: mechanism and magnitude of material loss

BACKGROUND: Wear of the underside of modular tibial inserts (backside wear) in total knee replacements has been reported by several authors. Although, for some implant designs, this phenomenon seems to contribute to osteolysis, the actual volume of material lost through wear of the backside surface has not been quantified. This study describes the results of computerized measurements of tibial inserts of one design known to be associated with a high prevalence of backside wear in situ. METHODS: A series of retrieved total knee components of one design were examined. The duration of implantation of the retrieved components ranged from thirty-six to 146 months. Laser surface profilometry and computer-aided design software were used to develop individual three-dimensional models of each worn, retrieved tibial insert to compare with scanned unused inserts. Volumetric subtraction of both models revealed the material lost because of backside wear. RESULTS: Worn and unworn areas on the backside surface were easily identified by stereomicroscopy and laser profilometry. The computer reconstructions showed that, in all retrievals, all unworn surfaces on the nonarticulating surface lay in one plane. The average volume (and standard deviation) of the material lost because of backside wear was 925 +/- 637 mm(3) (range, 197 to 2720 mm(3)). On the basis of the time in situ for each implant, the average volumetric wear rate was 138 +/- 95 mm(3)/yr. CONCLUSIONS: The predicted volume of material removed because of backside wear is substantial and may be sufficient to induce osteolysis. Our results suggest that peg-like protrusions are not generated by the extrusion of polyethylene into screw-holes within the base-plate but by abrasion of the underside of the bearing insert, leaving the protruding pegs as the only remnants of the original surface.