Soft tissue infection with Absidia corymbifera in a patient with idiopathic aplastic anemia

We describe a case of primary cutaneous mucormycosis (zygomycosis) in a patient with idiopathic aplastic anemia which responded to surgical debridement and therapy with liposomal amphotericin B. The tissue removed at surgery showed dense infiltration with fungal hyphae on histopathological examination. Primary cultures of tissue on solid media were negative, but Absidia corymbifera was isolated from unprocessed tissue placed in brain heart infusion broth.

Hybrid capture as a means of detecting human papillomavirus DNA from liquid-based cytology specimens: a preliminary evaluation

The connection between human papillomavirus (HPV) and cervical cancer is well documented, as is the benefit of an adjunctive, standardised objective test to complement cervical screening. Here, 197 liquid-based cytology (LBC) specimens previously processed for cytological examination (75 negative, 108 borderline/mild dyskaryosis, and 14 moderate/severe dyskaryosis) are examined for the presence of HPV using a hybrid capture assay. Of the 197 specimens tested for HPV DNA, 97 (49.2%) were positive using the combined high/low-risk probe, and 59 (29.9%) were negative cytologically and with the hybrid capture HPV test; however, 16/175 (21.3%) specimens classified as negative cytologically with LBC proved positive for HPV by hybrid capture. Of the 122 samples that showed abnormal cytology, 81 (66.4%) were positive for HPV. Although the number of samples tested is small, the results show that the use of LBC technology for both cervical cytological screening and the hybrid capture test has the potential to reduce both false-negative and -positive rates associated with cytological screening alone.

Fibrous histiocytoma of tendon sheath of the hand

The hand is not uncommonly afflicted by Fibrous histiocytoma/Giant Cell tumour of tendon sheath, an enigmatic and loosely-defined clinical entity only occasionally entering into the literature. The 26 cases in this clinico-pathologic review were obtained by a computerised search of histological files at the Dept. of Pathology, UCHG. Twice as many of these were female, more often in their fourth decade of life. The condition has a propensity for the long digits, more often the volar aspect and roughly evenly distibuted over each of the joints. Resection of these neoplasia is tedious due to it's propensity to grow between local anatomical structures contributing to a high recurrence rate. Interestingly it rarely figures in guesses at pre-operative diagnosis although the second commonest cause of a benign superficial hand mass after ganglion. We suggest that if this condition is suspected, referral to a specialist hand surgeon in the first instance is wise.

hMLH1 and hMSH2 expression correlates with allelic imbalance on chromosome 3p in non-small cell lung carcinomas

DNA mismatch repair genes have been implicated in the pathogenesis and predisposition of certain malignancies through a mutator phenotype. In this study, we investigated, in 150 non-small cell lung carcinomas, the expression levels of hMLH1 and hMSH2 proteins in relation to loss of heterozygosity on chromosomes 3p and 2p, the mutational status of these genes' promoters and the hot spot exons. We have demonstrated that 88 of 150 (58.6%) tumor specimens had reduced expression levels of the hMLH1 protein, whereas 85 of 147 (57.8%) specimens had reduced expression levels of the hMSH2 protein. Reduced expression levels of both proteins were observed in 51 of 150 (34%) specimens. In adenocarcinomas, the reduction of hMSH2 expression was more frequently observed than that of hMLH1 (P<0.003), whereas in squamous cell carcinoma of the lung hMLH1 expression was more frequently reduced than hMSH2 (P<0.006). Reduced expression of hMLH1correlated with allelic imbalance on loci D3S1289 (P<0.0002) and D2S391 (P<0.05). It is of note that an inverse correlation was found between hMSH2 reduced expression and loss of heterozygosity at locus D3S1300 (P = 0.016). In addition, hMLH1 reduced expression was more frequently associated with heavy smokers, assessed by daily tobacco uptake (P = 0.018) and total smoking exposure (pack-years; P<0.05). In addition, a correlation between hMLH1 reduced expression and nodal metastasis in squamous cell carcinoma of the lung was observed (P = 0.015). No mutations were identified in the promoters or exons examined in these two genes. These findings indicate that hMLH1 and hMSH2 gene inactivation is a common event in the development of non-small cell lung carcinoma and allelic loss seems to be a major genetic event involved in hMLH1 silencing. In addition, we propose that a putative negative regulator of hMSH2 gene may be located at the locus 3p14.

Telomerase activity in non-small cell lung carcinomas correlates with smoking status

Human telomerase is a ribonucleoprotein DNA polymerase which maintains the telomeric region of human chromosomes and has been detected in all types of human cancer tested. We used the telomeric repeat amplification protocol (TRAP) assay to examine 71 non-small cell lung carcinomas (NSCLC) and their adjacent normal tissue. Telomerase activity was detected in 61 (86%) of the 71 NSCLC examined but not in any of the matched normal lung tissues. A significant correlation was found between the presence of telomerase activity and current smoking status at the time of diagnosis (p=0. 0076). In addition, a trend was found between telomerase activity and smoking exposure (p=0.06). Our findings demonstrate that telomerase activity is a common phenomenon in NSCLC cases but not in the normal lung. However, certain cases in former smokers may follow a telomerase independent pathway.

Direct interaction of EEA1 with Rab5b

The early endosomal autoantigen EEA1 is essential for early endosomal membrane fusion. It binds to endosomes via a C-terminal domain (EEA1-CT). To identify proteins interacting with EEA1-CT, we screened a human brain library in the yeast two-hybrid system. Fourteen clones reacted strongly with EEA1-CT. Sequencing of these clones revealed that they all contained the ORF of the small GTPase, Rab5b. Further two-hybrid analysis suggested that Rab5b also interacts with the N-terminus of EEA1 (EEA1-NT). The interaction of both EEA1-CT and EEA1-NT with Rab5b was confirmed biochemically, and was found to be GTP dependent. Confocal immunofluorescence microscopy indicated that EEA1 colocalizes with Rab5b on early endosomes. Although EEA1-CT and EEA1-NT interacted strongly with wild-type Rab5b in the two-hybrid system, we detected no interaction with wild-type Rab5a, even though GTPase-deficient mutants of both Rab5a and Rab5b interacted equally well with EEA1. This difference could not be explained by differences in intrinsic GTPase activities, as these were found to be very similar. Instead, we speculate that yeast may contain a GTPase-activating protein (GAP) activity that stimulates Rab5a but not Rab5b. In contrast, pig brain cytosol was found to contain a GAP activity that stimulates the GTPase activity of Rab5b in preference to that of Rab5a. These data provide evidence that EEA1 interacts with both Rab5a and Rab5b, and that the GTPase activities of the two proteins are differentially regulated in vivo.

The endosome fusion regulator early-endosomal autoantigen 1 (EEA1) is a dimer

EEA1, an early-endosomal protein originally identified as an autoantigen, is essential for endocytic membrane fusion. It interacts with early endosomes via binding to the membrane lipid phosphatidylinositol 3-phosphate (PtdIns3P) and the active form of the small GTPase Rab5. Most of the EEA1 sequence contains heptad repeats characteristic of proteins involved in coiled-coil protein-protein interactions. Here we have investigated the ability of EEA1 to self-interact. Crosslinking of cytosolic and recombinant EEA1 resulted in the disappearance of the 180-kDa monomer in SDS/PAGE and the strong appearance of a approximately 350-kDa crosslinked product. Glycerol gradient centrifugation experiments indicated that native EEA1 had the same hydrodynamic properties as the approximately 350-kDa crosslinked complex. Two-hybrid analysis indicated that N- and C-terminal fragments of EEA1 can interact with themselves, but not with each other, suggesting that EEA1 forms parallel coiled-coil dimers. The ability of the C-terminus of EEA1 to dimerize correlates with its ability to bind to Rab5 and early endosomes, whereas its binding to PtdIns3P is independent of dimerization. These data enable us to propose a model for the quaternary structure of EEA1.

EEA1 links PI(3)K function to Rab5 regulation of endosome fusion

GTPases and lipid kinases regulate membrane traffic along the endocytic pathway by mechanisms that are not completely understood. Fusion between early endosomes requires phosphatidylinositol-3-OH kinase (PI(3)K) activity as well as the small GTPase Rab5. Excess Rab5-GTP complex restores endosome fusion when PI(3)K is inhibited. Here we identify the early-endosomal autoantigen EEA1 which binds the PI(3)K product phosphatidylinositol-3-phosphate, as a new Rab5 effector that is required for endosome fusion. The association of EEA1 with the endosomal membrane requires Rab5-GTP and PI(3)K activity, and excess Rab5-GTP stabilizes the membrane association of EEA1 even when PI(3)K is inhibited. The identification of EEA1 as a direct Rab5 effector provides a molecular link between PI(3)K and Rab5, and its restricted distribution to early endosomes indicates that EEA1 may confer directionality to Rab5-dependent endocytic transport.

Elder abuse and one community's response

Elder abuse has come to be recognized as any act of both commission or omission that causes harm or loss to elderly people. This can include active or passive neglect, violence, sexual or emotional abuse, various kinds of theft, and deprivation of the person's human rights. Elder abuse has many causes. The Hastings and Prince Edward Council on Aging developed an Elder Abuse Community Response Protocol to help address this problem.

Inhibition of dihydropyrimidine dehydrogenase by 5-propynyluracil, a metabolite of the anti-varicella zoster virus agent netivudine

OBJECTIVE

To study the effects of the anti-herpetic drug netivudine on dihydropyrimidine dehydrogenase activity in elderly volunteers and to relate them to concentrations of netivudine and its metabolite 5-propynyluracil.

METHODS

Three groups of eight elderly volunteers received 400 or 800 mg netivudine or placebo once daily for 8 days. Plasma netivudine, 5-propynyluracil, and uracil, an indirect measure of dihydropyrimidine dehydrogenase activity, were assayed before the first dose and on days 2, 3, 5, 7 and 8. Full plasma profiles of netivudine and 5-propynyluracil were determined after the last dose.

RESULTS

Plasma uracil was unquantifiable in all subjects before the first dose and at all time points in the placebo group. In recipients of netivudine it reached a plateau between days 3 and 5, with mean values of 23.2 and 23.5 mumol/L on day 8 in the subjects who received 400 and 800 mg. Plasma netivudine concentrations were approximately dose proportional, but 5-propynyluracil concentrations were similar in both groups. The half-maximal rise in plasma uracil occurred after a cumulative 5-propynyluracil exposure of 120 mumol/L.hr; such exposures will be achieved even after doses as low as 50 to 100 mg daily.

CONCLUSIONS

Netivudine dosing produces complete inhibition of plasma dihydropyrimidine dehydrogenase. Coadministration with the antimetabolite 5-fluorouracil will require a substantial reduction in 5-fluorouracil dose to avoid toxicity but may also improve the therapeutic index of 5-fluorouracil.

Intravenous methylmethacrylate following cemented total hip arthroplasty

Both cemented and noncemented techniques have been used for total hip arthroplasty (THA). Each technique has advantages and disadvantages. Among the disadvantages of cemented THA are several perioperative complications, such as intraoperative cardiac or respiratory failure and hypotension, called "cement implantation syndrome," and extrusion of cement beyond the confines of the medullary canal. Cement extrusion can be the result of overreaming of the femoral canal and cortical perforation. This is a worrisome finding, as the risk of subsequent femoral fracture at the site of perforation is increased. Extruded cement, however, does not always indicate a problem. Extruded cement located within the femoral venous system, intravenous methylmethacrylate, for example, is not associated with long-term complications. While uncommon, it is important to differentiate this finding from the more serious cortical perforation. We report four examples of intravenous methylmethacrylate following THA and describe the imaging features that allow differentiation of this entity from the more significant finding of cortical perforation.

Twenty-five years of gallbladder surgery in a small rural hospital

BACKGROUND

During a 25-year period from 1967 to 1991, 1,058 gallbladder operations were done by one surgeon in solo practice in a rural 50-bed hospital.

METHODS

Open cholecystectomy was performed on all but 6 patients who had cholecystostomy. Operative cholangiography was liberally used, and 19% of all patients required common duct exploration. The majority of the patients were older than 65 years of age and 19% were older than 75 years of age.

RESULTS

The overall mortality was 0.7%. There were no deaths following cholecystectomy for chronic or acute nongangrenous cholecystitis, and all deaths occurred in patients older than 77 years of age. Most of the deaths occurred prior to 1978 and the last death was recorded in 1984.

CONCLUSIONS

Rural America has a comparatively large proportion of the elderly population of our nation. Most of these patients prefer to have their surgery performed locally, provided the results are comparable with those of large neighboring medical centers. The results from this current series from a small rural hospital compare favorably with the published results from large medical and academic centers.

A twenty-five year survey of a solo practice in rural surgical care

A large proportion (55 million) of our population lives in rural America, but there is a paucity of published material regarding the surgical care of this large group. This report is based on 13,793 patients treated in a 50-bed rural hospital by one surgeon during a period of 25 years from 1967 to 1991. Gynecologic, obstetric, orthopedic and urologic surgical treatment accounted for 41 percent of extensive operations, but endoscopic procedures have been increasing in recent years. Good surgical results can be obtained in the smaller rural hospital, but more emphasis on broader training for the would-be rural surgeon is necessary for this to continue.

Surgery for Crohn's disease

In the last 12 years, 72 operations have been performed on 41 patients for Crohn's disease in this hospital. The patients were predominantly young (mean age 32 yrs) and there were more females than males. 28 had ileocolic disease, three small intestinal, two pan-enteric and eight colonic. Pain (in 76%), diarrhoea (56%) and weight loss (66%) were the main presenting symptoms. Diarrhoea occurred in all those with colonic disease, but in only 43% of those with ileocolic disease. A right hemicolectomy (28 patients), colonic resection (12) and small intestinal resection (9) were the commonest operations. There were no deaths. 22 patients had a total of 26 complications after surgery, eight necessitating further surgery. The mean post-operative stay was 15 days, being lowest in those with ileocolic disease. 19 patients have required only one operation, with a mean follow-up of 5.3 years. These patients also had significantly less complications (p < 0.05). Half of the patients requiring surgery for Crohn's disease have done very well. The other half require many operations and have a substantial morbidity.

Chondro-osteodystrophy (Morquio Brailsford disease, mucopolysaccharidosis type IV A)

We report three cases of Morquio Brailsford Disease (Mucopolysaccharidosis Type IV A) in an Irish family. We are unaware of any previous similar report from this Country.

An evaluation of the usefulness of primary tumour expression of MCA and CA15-3 as prognostic indicators in breast carcinoma

CA15-3 antigen and mucin-like carcinoma associated antigen (MCA) show potential as clinically useful serum markers of breast carcinoma. Recently, immunohistochemical versions of these monoclonal antibodies have become available but few data are available as to their clinical usefulness. The aims of this study were (i) to assess CA15-3 and MCA expression by primary breast tumours and to correlate tumour immunoreactivity with tumour behaviour, and (ii) to investigate the relationship between immunohistological staining and oestrogen receptor (ER) status. Pathological material from 39 stage 1 (node free) breast carcinoma patients was assessed. The mean age was 51.3 (range 34-70) years, 19 were premenopausal and the mean duration of follow-up was 3.6 years (range 0.8-14 years). In each case two further sections were stained with antisera to the CA15-3 and MCA antigens. Staining of primary tumour was achieved in 38 cases. Low (less than 30% tumour cell staining) and intermediate (30-60% of cells staining) grade immunoreactivity with both monoclonals correlated with significantly shorter disease free intervals (P less than 0.05). Neither monoclonal can predict ER status. We conclude that the use of monoclonal antibodies to CA15-3 and MCA in staining primary breast carcinoma tumours and their axillary nodes may be a significant (P less than 0.05) prognostic indicator of future tumour behaviour and that this requires further evaluation.