The development of unit activity in the lateral geniculate nucleus of the kitten

The spontaneous unit activity in the lateral geniculate nucleus of 15 kittens has been analyzed in terms of the sleep-wake state. Lateral geniculate units in animals ranging from 2 days to 5 weeks of age were recorded under chronic conditions by means of a hydraulically movable glass micropipet. During the first postnatal month, the mean frequency of firing increased progressively in the awake state and in paradoxical sleep but was not modified in quiet or slow wave sleep. However, as early as the third postnatal week, the pattern of modulation of the frequency of unit discharge in response to changes in state reached an organization close to that seen in the adult cat. The most dramatic alteration in the cellular discharge configuration was represented by the introduction of the “burst-pause” pattern in slow wave sleep. Serial interspike interval distributions demonstrated the appearance of this pattern at the end of the second week. The organization of unit firing in the 1-month-old animal was qualitatively similar to that in the adult, though quantitatively less intense. The pattern of development of unit firing is discussed in light of the appearance of other important developmental features such as cortical synchronization, ponto-geniculo-occipital spikes, and maturation of certain monamine-containing cells in the central nervous system. Some structural and neurochemical factors in development are mentioned that may be responsible for the ontogenetic organization of unit discharges in the lateral geniculate nucleus.     

Lung cancer and occupation in nonsmokers: a multicenter case-control study in Europe

BACKGROUND: Tobacco smoking is the main cause for lung cancer worldwide, making it difficult to examine the carcinogenic role of other risk factors because of possible confounding by smoking. Therefore, the present study aimed to investigate the association between lung cancer and occupation independent of smoking. METHODS: A case-control study of lung cancer was carried out between March 1998 and January 2002 in 16 centers from 7 European countries, including 223 never-smoking cases and 1039 controls. Information on lifestyle and occupation was obtained through detailed questionnaires. Job and industries were classified as entailing exposure to known or suspected carcinogens; in addition, expert assessment provided exposure estimates to specific agents. RESULTS: The odds ratio of lung cancer among women employed for more than 12 years in suspected high-risk occupations was 1.75 (95% confidence interval = 0.63-4.85). A comparable increase in risk was not detected for employment in established high-risk occupations or among men. Increased risk of lung cancer was suggested among individuals exposed to nonferrous metal dust and fumes, crystalline silica, and organic solvents. CONCLUSION: Occupations were found to play a limited role in lung cancer risk among never-smokers. Jobs entailing exposure to suspected lung carcinogens should receive priority in future studies among women. Nonferrous metal dust and fumes and silica may exert a carcinogenic effect independently from smoking.     

Comparison of metabolic monitors in critically ill, ventilated patients

OBJECTIVE: We compared the Deltatrac II, the M-COVX, and the Evita 4 metabolic monitoring devices under clinical conditions. METHODS: A prospective simultaneous clinical comparison was performed in a general intensive care department of a tertiary university hospital in 43 ventilated, critically ill patients. The monitors were compared simultaneously. After 30 min of steady state, oxygen consumption per unit time, carbon dioxide consumption per unit time, resting energy expenditure, and respiratory quotient were recorded for the Deltatrac II; the same parameters in addition to end-tidal carbon dioxide and fraction of inspired oxygen were recorded for the M-COVX; and carbon dioxide consumption per unit time, end-tidal carbon dioxide, and fraction of inspired oxygen were recorded for the Evita 4. Pulmonary gas-exchange measurements from the Deltatrac II and resting energy expenditure and respiratory quotient from the M-COVX were obtained after 30 min. The other parameters were calculated from the last five measurements obtained at the end of the study period. RESULTS: A good correlation was found between oxygen consumption per unit time and resting energy expenditure as obtained from the Deltatrac II and the M-COVX (r = 0.76 and 0.75, respectively; P < 0.001), but the correlation was lower between carbon dioxide consumption per unit time as obtained from the Deltatrac II and the M-COVX or Evita 4 (r = 0.67 and 0.48, respectively). Agreement between the different methods did not reach clinical acceptability, exceeding a 20% difference using the Bland-Altman statistical methods. CONCLUSION: Poor agreement was found between the Deltatrac II and M-COVX or Evita 4 metabolic monitors, despite a good correlation between measurements, leading to the conclusion that the M-COVX and Evita 4 provide less accurate measurements of metabolic gas exchange in stable ventilated patients. These devices can be used for daily nutritional assessment and continuous monitoring, but the Deltatrac II remains the method of choice for metabolic measurement.     

A control-matched comparison of laser epithelial keratomileusis and laser in situ keratomileusis for low to moderate myopia

PURPOSE: To compare the visual and refractive outcomes of laser epithelial keratomileusis (LASEK) and laser in situ keratomileusis (LASIK) for the treatment of low to moderate myopia. DESIGN: Retrospective, nonrandomized, control-matched study. METHODS: The charts of 2257 eyes that underwent LASEK or LASIK treatment were reviewed. Patients who were 21 years of age or older having between -0.75 and -6.00 diopters (D) of myopia with up to -2.25 D of astigmatism were included. One hundred twenty-two LASEK-treated eyes were matched with 122 LASIK-treated eyes having preoperative spheres, cylinders, and spherical equivalent (SE) within +/-0.50 D. Both groups had similar preoperative best spectacle-corrected visual acuity (BSCVA), laser platform, and follow-up durations. Outcome measures were visual and refractive results. RESULTS: Preoperatively, the mean SE was -3.50 +/- 1.40 D for LASEK and -3.50 +/- 1.42 D for LASIK (P = .59). Postoperatively, the mean logarithm of minimum angle of resolution (logMAR) uncorrected visual acuity (UCVA) was 0.01 +/- 0.08 (20/21) for LASEK and 0.06 +/- 0.12 (20/23) for LASIK; the mean SE was -0.15 +/- 0.40 D for LASEK and -0.37 +/- 0.45 D for LASIK; and the mean logMAR of BSCVA was -0.03 +/- 0.06 (20/19) for LASEK and -0.02 +/- 0.05 (20/19) for LASIK. No eye lost 2 or more lines of BSCVA in both groups. CONCLUSIONS: Slight differences in the visual and refractive results between LASEK and LASIK were observed, despite the use of the same nomogram. Both procedures were safe, effective, and predictable. Nomogram adjustment may be necessary for LASIK surgeons adopting surface ablation.     

The effect of cyclo-DfKRG peptide immobilization on titanium on the adhesion and differentiation of human osteoprogenitor cells

This study takes place in the field of development of a bioactive surface of titanium alloys. In this paper, titanium was functionalized with cyclo-DfKRG peptide by coating or grafting using different anchors (thiol or phosphonate) as spacers between the surface and the peptide. Cell adhesion, and differentiation of human osteoprogenitor (HOP) cells arising from human bone marrow were investigated. Our results seem to demonstrate that cyclo-DfKRG peptide coating with a phosphonate anchor and grafting procedure contributes to higher cell adhesion and a strong ALP and Cbfa1 mRNA expression, after 10 days of cell seeding. At the contrary, this peptide coated with a thiol anchor stimulates differentiation of HOP within 3 days of culture.     

Surgical Management of Metastases to the Thyroid Gland

Background

Metastases to the thyroid gland are uncommon, with rates reported between 0.02% and 1.4% of surgically resected thyroid specimens. Our goal was to present our experience with surgical management of metastases to the thyroid gland.

Methods

Twenty-one patients with metastatic disease to the thyroid were identified from a database of 1,992 patients with thyroid cancer who had surgery during 1986–2005. Patient, tumor, treatment, and outcome details were recorded by analysis of charts. The median age at time of surgery was 68 (range, 39–83) years; 12 were men and 9 were women.

Results

All patients were managed by surgery, including lobectomy in ten patients, total thyroidectomy in six, completion thyroidectomy in two, and subtotal thyroidectomy in one. In two patients, the thyroid lesion was found to be unresectable at the time of surgery. Histopathology revealed renal cell carcinoma in ten, malignant melanoma in three, gastrointestinal adenocarcinoma in three, breast cancer in one, sarcoma in one, and adenocarcinoma from an unknown primary site in three patients. Seventeen patients have died. The cause of death in all 17 was widespread metastatic disease from their respective primary tumors. The median survival from surgery to death or last follow-up was 26.5 (range, 2–114) months.

Conclusions

In patients with metastases to the thyroid gland, local control of metastatic disease in the central compartment of the neck can be successfully achieved with minimal morbidity with surgical resection in selected patients.     

Select screening in a specific high-risk population of patients suggests a stage migration toward detection of non-muscle-invasive bladder cancer

Background

More than 25% of bladder cancer (BC) cases are still muscle-invasive at first diagnosis. Screening is unproven to enable the detection of more non–muscle-invasive tumors. BC association with aristolochic acid nephropathy (AAN) was reported after intake of slimming pills containing Chinese herbs.

Objective

We evaluated whether a BC screening protocol in a high-risk and unique patient population had an impact on the stage of tumor presentation.

Design, setting, and participants

Forty-eight AAN-affected patients were enrolled in a screening program, establishing BC incidence during prospective screening cystoscopies and biopsies biannually for up to 10 yr. Two patients were lost to follow-up, and three refused screening after consenting.

Measurements

Patients were evaluated for presence of BC and tumor stage at diagnosis.

Results and limitations

BC was diagnosed in 25 patients (52%). Among 43 patients who underwent screening cystoscopies (median follow-up: 94 mo), 22 were first diagnosed with non–muscle-invasive BC but none with muscle-invasive tumors and none died of BC. Three women who declined follow-up were diagnosed and died with advanced metastatic disease. The limitations of our findings include the small sample size of this case series, the absence of a real control group, and the particular risk factor in these patients that differs from the usual risk factors, such as smoking or industrial chemicals.

Conclusions

BC screening in high-risk groups may allow identification of tumors before muscle invasion. The optimal screening schedule and the relevance of the present findings in smoking-related BC remain to be defined.