ABSTRACT
To analyse initial tobacco-related cellular alterations in the upper aerodigestive tract, we investigated the proliferation state in paraffin embedded samples of tumour-adjacent histologically normal mucosa from head and neck squamous cell carcinoma (HNSCC) patients and normal buccal mucosa from healthy individuals. The proliferation index (PI) was assessed by indirect immunohistochemical staining for the proliferation marker Ki-67. Only a slight rise in PI was seen in the normal epithelium from non-smoking HNSCC patients in comparison with the epithelium from non-smoking healthy individuals. The epithelia from the smoking HNSCC patients and from the healthy smoking individuals both showed an increased PI compared with epithelia from the non-smoking HNSCC patients and healthy individuals (P = 0.001). In addition, the ex-smokers in both groups still showed a trend towards increased PI. Increased PI after cessation of smoking could indicate permanent epithelial alterations. Our findings provide new evidence for the concept of field cancerisation.
Subject(s)
Carcinoma, Squamous Cell/pathology , Head and Neck Neoplasms/pathology , Smoking/pathology , Adult , Aged , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Female , Humans , Immunohistochemistry , Ki-67 Antigen/metabolism , Male , Middle Aged , Mouth Mucosa/metabolism , Mouth Mucosa/pathology , Smoking/metabolismABSTRACT
The development of a polymerase chain reaction (PCR) based fingerprinting method for the characterization of Giardia duodenalis isolates is described. The method uses three different PCRs; one is specific for the A ("Polish") major group of G. duodenalis isolates, another is specific for the B ("Belgian") group of isolates; and one amplifies a fragment of the glutamate dehydrogenase gene present in all G. duodenalis isolates. The PCRs perform highly sensitively on DNA from cultured trophozoites. Isolates were further characterized by restriction-fragment-length polymorphism (RFLP) analysis of the PCR products. In this way, representative isolates from the A and B groups could be grouped together into a number of subgroups. The stability of the genotypes with time and the reproducibility of the two methods were tested on cloned and subcloned lines from a number of isolates and proved to be highly satisfactory. The PCR/RFLP method was evaluated on cysts derived from a number of human patients. It is concluded that the PCR fingerprinting method described in this paper provides a reliable characterization method for Giardia isolates and has the potential to be used as a direct method of typing G. duodenalis cysts from feces.
Subject(s)
Giardia/genetics , Giardia/isolation & purification , Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Cloning, Molecular , DNA Fingerprinting/methods , DNA Primers , DNA, Protozoan/genetics , DNA, Protozoan/isolation & purification , Feces/parasitology , Giardia/classification , Giardiasis/diagnosis , Giardiasis/parasitology , Humans , Infant , Middle Aged , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , Restriction MappingABSTRACT
A servo-controlled foot platform was used to quantify, in upright stance, the thresholds for sensing ankle inversion and eversion movements in seven geriatric patients with peripheral neuropathy (PN) confirmed by nerve conduction studies and seven age- and gender-matched (C) controls with normal nerve conduction function. The PN group had a 4.6-fold larger (p = 0.0026) threshold (mean [SD] 1.37 [1.74]degrees) for perceiving the presence and direction of an ankle rotation at a 75% rate of success (TH75) than did the C group (0.3[0.17]degrees). Inversion acuity was approximately twice that of eversion acuity in both groups. The PN group demonstrated better proprioceptive acuity in unipedal stance than in bipedal stance, whereas no such difference was found in the C group. Semiquantitative clinical tests of PN group proprioception at the ankle performed in the seated position failed to demonstrate significant differences from controls save in one case; however, the results of such tests at the toe were abnormal in all patients. In the geriatric population, PN is associated with deficits in ankle proprioception known theoretically to hamper maintenance of unipedal balance. It is significant that these deficits are associated with a clinically demonstrable loss of position sense at the toe but not the ankle.
Subject(s)
Peroneal Nerve , Proprioception , Sural Nerve , Tibial Nerve , Aged , Ankle/innervation , Case-Control Studies , Electromyography , Female , Geriatric Assessment , Humans , Male , Neural Conduction , Peripheral Nervous System Diseases/diagnosisABSTRACT
A randomized quadruple staircase method and probit analysis were used to measure the thresholds for sensation of ankle inversion and eversion by 18 healthy young and 18 healthy old subjects while standing with a foot in a servo-driven cradle. The results of over 3600 trials show that the mean threshold for detecting inversion with a probability of 75% was 0.35 degrees in the older subjects, a value significantly greater than the 0.06 degrees threshold found in the younger group. The corresponding thresholds in eversion were significantly greater in both old (0.52 degrees) and young (0.35 degrees) subjects. Significant, but smaller, age differences were also found in unipedal stance. Few significant sex differences were found. When the velocity of a 0.1 degree inversion movement was increased from 2 to 200 degrees/s the probability of detecting it rose by only 22.6%. Although significantly increased with age, the threshold for sensing rotation in the weight-bearing ankle was measured in tenths of degrees, an order of magnitude better than previously reported (non-weight-bearing) values.
