Gene mutations in saliva as molecular markers for head and neck squamous cell carcinomas

BACKGROUND

Cancer is caused by the accumulation of mutations that activate proto-oncogenes and inactivate tumor suppressor genes. The result is a clonal expansion of genetically identical daughter cells that eventually become clinical malignancies. The specific mutations acquired by the progenitor cell are like a fingerprint carried by each cell of the tumor. These mutations can serve as very specific markers for the presence of tumor cells in a background of normal cells.

METHODS

Mutations in the p53 gene recovered from head and neck squamous cell carcinomas were sequenced, and these altered DNA sequences were used retrospectively as tumor-specific genetic markers for cancer cells in the patient's saliva. Cloned p53 sequences amplified by the polymerase chain reaction from DNA extracted from banked preoperative saliva specimens were screened for the presence of tumor-specific mutations using radiolabeled oligonucleotide probes.

RESULTS

We identified tumor-specific mutations in preoperative saliva samples of 5 of the 7 patients evaluated (71%).

CONCLUSIONS

These results suggest a potential for clinical applications of this novel approach to cancer detection using gene mutations as molecular markers for carcinomas.

Microsatellite alterations as clonal markers for the detection of human cancer

Microsatellite instability has been reported to be an important feature of tumors from hereditary nonpolyposis colorectal carcinoma (HNPCC) patients. The recent discovery of genetic instability in small cell lung carcinoma, a neoplasm not associated with HNPCC, led us to investigate the possible presence of microsatellite alterations in other tumor types. We examined 52 microsatellite repeat sequences in the DNA of normal and tumor pairs from 100 head and neck, bladder, and lung cancer patients by the polymerase chain reaction. Although alterations were rare in dinucleotide repeats, larger (tri- or tetranucleotide) repeats were found to be more prone to expansion or deletion. We screened 100 tumors with a panel of nine tri- and tetranucleotide repeat markers and identified 26 (26%) that displayed alterations in at least one locus. This observation prompted us to examine the possibility of using microsatellite alterations as markers to detect clonal tumor-derived cell populations in pathologic samples. The identical microsatellite alterations detected in the primary tumors were successfully identified in corresponding urine, sputum, and surgical margins from affected patients. This study demonstrates that appropriately selected microsatellite loci are commonly altered in many cancers and can serve as clonal markers for their detection.

p53 gene mutations as markers of tumor spread in synchronous oral cancers

OBJECTIVE

To demonstrate how genetic mutations may be used as specific markers for the study and management of head and neck squamous cell carcinomas.

DESIGN

Mutations in the p53 gene were identified by DNA sequencing in synchronous primary head and neck squamous cell carcinomas from one patient. The polymerase chain reaction and mutant-specific oligomer probes were used to detect rare tumor cells in surgical margins, lymph nodes, and swabs of the oral cavity.

PATIENTS

Selected from a consecutive series of individuals with head and neck squamous cell carcinomas at a tertiary referral center.

RESULTS

Two synchronous primary invasive cancers displayed different missense mutations in the p53 gene. The mutated sequence from one primary tumor was detected in metastases from both sides of the neck. Infiltrating cells from this biologically aggressive tumor were also detected by a polymerase chain reaction-based assay in a histologically normal surgical margin, accurately predicting tumor recurrence.

CONCLUSIONS

p53 gene mutations were useful as molecular markers to distinguish between tumors in this case. The potential utility of detection of tumor cells in surgical margins and saliva by molecular techniques merits further investigation.

Inhibition of glutamate uptake in the rostral ventrolateral medulla enhances baroreflex-mediated bradycardia in conscious rats

The current investigation tested the hypothesis that inhibition of L-glutamate uptake in the rostral ventrolateral medulla (RVL) enhances the baroreceptor-mediated heart rate responses. In conscious freely moving rats, unilateral microinjection of the L-glutamate uptake blocker p-chloromercuriphenylsalfonic acid (PCMS, 0.1 nmol) elicited a 45% increase in the baroreflex-mediated bradycardic response tested by i.v. phenylephrine (-2.0 +/- 0.1 vs -2.9 +/- 0.2 beats/min/mmHg). In the same rats, evidence for the ability of PCMS to inhibit L-glutamate uptake at the site of its microinjection in the RVL was obtained. PCMS microinjected into the RVL did not influence basal blood pressure and heart rate. However, the cardiovascular responses elicited by L-glutamate (5 nmol) microinjected into the RVL were significantly enhanced by PCMS pretreatment. The pressor and bradycardic responses to L-glutamate increased 53% (from 28.3 +/- 2.4 to 43.4 +/- 4.7 mmHg) and 68% (from -59.6 +/- 13.1 to -100.0 +/- 7.2 beats/min), respectively after PCMS. An equal volume of ACSF microinjected into the RVL had no effect on BRS (-2.1 +/- 0.2 vs -1.9 +/- 0.1 beats/min/mmHg), nor on the pressor (29.9 +/- 7.4 vs 30.6 +/- 4.4 mmHg) and bradycardic (-50.3 +/- 12.0 vs -43.3 +/- 12.0 beats/min) responses elicited by L-glutamate. These findings suggest that: (i) glutamatergic pathways in the RVL serve a facilitatory role in processing the baroreceptor information, and (ii) L-glutamate uptake mechanisms exert a restraining influence on BRS and the cardiovascular effect of L-glutamate.

Blue-light generation by frequency doubling of an 810-nm cw GaAlAs diode laser in a quasi-phase-matched LiNbO(3) crystal

A third-order quasi-phase-matched LiNbO(3) crystal was used to double the output of an 810-nm cw GaAlAs diode laser directly. A blue-light output power of 0.35 mW was measured with a conversion efficiency of 0.13%.

ANG II receptor blockade prevents ventricular hypertrophy and ANF gene expression with pressure overload in mice

There is increasing evidence that the renin-angiotensin system may play a important role in cardiac hypertrophy. To assess the role of angiotensin II in the induction of cardiac hypertrophy, three groups of adult mice were subjected to left ventricular pressure overload by transverse aortic constriction (TAC). For the next 7 days the groups received either the specific angiotensin II subtype 1 receptor (AT1) antagonist (losartan, 1.05 g/l; n = 17), an angiotensin enzyme inhibitor (captopril, 2 g/l; n = 17), or no treatment (n = 22) administered in the drinking water and compared with three similarly treated sham-operated groups (n = 7 each). TAC resulted in a significant increase in heart weight-to-body weight ratio (0.634 +/- 0.087 vs. 0.525 +/- 0.039, g/g x 100, P < 0.05), which was prevented by losartan (0.506 +/- 0.069, g/g x 100, P < 0.0001) despite similar hemodynamic load (proximal systolic pressure 146 +/- 31 vs. 136 +/- 32 mmHg, untreated vs. losartan, P = NS). Proximal systolic pressure was positively correlated with the development of ventricular hypertrophy. In the presence of AT1-receptor blockade, the increase in heart weight-to-body weight ratio at any given systolic pressure was significantly attenuated compared with untreated TAC mice. The increase in heart weight-to-body weight ratio was also significantly attenuated by captopril compared with untreated banded controls (0.542 +/- 0.091, g/g x 100, P = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of oncogene mutations in sputum precedes diagnosis of lung cancer

The Johns Hopkins Lung Project developed an archive of sputum specimens during a randomized trial of lung cancer screening (1974-1982). We identified 15 patients from that trial who later developed adenocarcinoma of the lung. The primary lung carcinomas from 10 of these 15 patients contained either a ras or a p53 gene mutation. Using a polymerase chain reaction-based assay, stored sputum samples obtained prior to clinical diagnosis were examined for the presence of these same oncogene mutations. In 8 of 10 patients, the identical mutation identified in the primary tumor was also detected in at least one sputum sample. The earliest detection of a clonal population of cancer cells in sputum was in a sample obtained more than 1 year prior to clinical diagnosis. These results provide the basis of a novel approach for detection of lung cancer based on the evolving molecular genetics of this disease.

In vivo assessment of left ventricular remodelling after myocardial infarction by digital video contrast angiography in the rat

OBJECTIVE

The aim was to develop a digital video contrast angiographic method for assessing global left ventricular function and volume in vivo in the rat and then to apply it to a study of ventricular remodelling after coronary occlusion, with and without reperfusion.

METHODS

Digital contrast angiography was performed on 29 rats, including the following groups: sham operated (n = 11), non-transmural myocardial infarction produced by reperfusion (n = 8), and transmural infarction produced by permanent occlusion (n = 10). Under anaesthesia three weeks later, biplane fluoroscopic images were acquired following venous contrast injection. Levophase images were digitised, and left ventricular end diastolic and end systolic volumes and ejection fractions were obtained using an area-length method. Left ventricular ejection fraction data also were calculated by videodensitometry from video density curves.

RESULTS

Compared to the sham operated group, the reperfused group showed a significant decrease in left ventricular ejection fraction, at 53(SD 7) v 70(5)% (p < 0.01), and an increase in end diastolic volume. The permanent occlusion group showed a further decrease in the ejection fraction [40(8)%] and a further significant increase in end diastolic volume compared to the reperfused group (p < 0.01). Left ventricular ejection fraction correlated inversely with percent infarct size (r = 0.882) and showed a positive correlation with the spared epicardial area (r = 0.721). Most haemodynamic variables, including maximum left ventricular dP/dt, failed to discriminate between the groups. The methods showed reasonable accuracy when tested in vitro using contrast filled balloons. In vivo, the left ventricular ejection fraction calculated by densitometry showed adequate interobserver variability (2 SD +/- 8.5 percentage points), but the area-length method showed somewhat more scatter.

CONCLUSIONS

Digital video contrast angiography is a feasible method for the assessing global left ventricular function in the rat and should be useful in other small animal models. Significant differences in left ventricular volumes and ejection fractions were detected between reperfused and permanent occlusion groups, whereas haemodynamic variables showed non-significant trends. Reperfusion after 45 min of occlusion caused sparing of the epicardium, prevented unfavourable remodelling, and improved the ejection fraction compared to permanent occlusion.

Effect of caval-portal shunt on ovarian tissue in rats: I. Histological observation

Forty-three female Sprague Dawley rats were divided into five groups, with groups 1-4 subjected to end-to-side caval-portal shunt (CPS). In addition to CPS, group 1 (n = 13), group 2 (n = 10), and group 3 (n = 7) rats had undergone removal of the right ovary and one-half of the left ovary, the left ovary, and one-half of the left ovary, respectively. Group 4 (n = 6) rats were not subjected to ovariectomy. Group 5 (n = 7) animals were not subjected to CPS but underwent left ovarian hemiresection. The ovarian volume of the hemiresected ovaries increased to 393.00 +/- 4.83 mm3 and 126.00 +/- 44.3 mm3 from 18.40 +/- 0.54 mm3 and 18.40 +/- 0.59 mm in groups 1 and 3, respectively, at the end of three postoperative months. The nonresected ovaries enlarged to 339.98 +/- 5.09 mm3 and 226.3 +/- 46.2 mm3 from 36.79 +/- 1.09 mm3 in groups 2 and 3, respectively. When no ovaries were resected, the CPS animals in group 4 showed an increment of ovarian volume of 1.75-2.2 times as much as the preoperative ones. In the animals that had undergone simple hemiovariectomy (group 5), the contralateral ovaries showed a significant increase in volume (40.2 +/- 8.3 mm3 to 243.1 +/- 114.8 mm3) at 3 months. The hemiresected ovarian volume increased from 27.1 +/- 5.5 mm3 to 44.1 +/- 11.8 mm3.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and experimental studies on tong yu ling in the treatment of diabetic hyperlipemia

72 diabetes mellitus patients (70 cases non-insulin-dependent) were treated routinely with D860. After one month, cases with persisting hyperglycemia and hyperlipemia were randomly divided into Group A to be treated with D860 plus Tong Yu Ling (TYL), and Group B to continue treatment with D860 alone, while Group C, comprising cases with persisting hyperlipemia only, were treated with TYL alone. Therapeutic results showed that of the total 50 cases of Group A and C, 26 were markedly improved, 14 improved, and 10 cases ineffective. The antihyperlipemic effect was pronounced in Group A, where the blood cholesterol, beta-lipoprotein and triglyceride showed remarkable decline, less pronounced in Group C, and insignificant in Group B. Experiments in rat models of non-insulin-dependent diabetes demonstrated that TYL was markedly effective in treating hyperlipemia.

Comparison of the antinociceptive effects induced by electroacupuncture and transcutaneous electrical nerve stimulation in the rat

The analgesic effects induced by two different kinds of peripheral conditioning stimulations, electroacupuncture (EA) and transcutaneous electrical nerve stimulation (TENS), were compared in the rat using the latency of radiant heat-evoked tail flick reflex as nociceptive index. The parallel elevations of withdrawal latency of tail flick were produced by EA and TENS administrations at the acupoints of S36 and Sp6 with low intensity (1-2-3 mA) and one of three different frequencies (2, 15 and 100 Hz). Analgesic effects of EA or TENS were characterized by slow-on and slow-off nature, and a significant linear correlation was found between both at any one of three frequencies. Systemic naloxone hydrochloride (2 mg/kg) almost completely and partially antagonized 2 and 15 Hz EA- or TENS-induced analgesia, respectively, but failed to affect those induced by 100 Hz EA or TENS. Tolerance to EA stimulation with one of three frequencies reduced the corresponding frequency TENS-induced analgesia and vice versa. These data indicate that: (a) there is no significant difference in producing antinociception for two different peripheral conditioning stimulations when applied at the same sites and (b) the common neural mechanisms most likely process the analgesic effects of EA and TENS. The involvement of (an) endogenous opiate mechanism in the management of different frequency EA and TENS analgesia is discussed in detail.

Dietary vitamin and mineral concentrations of two juvenile female giant pandas (Ailuropoda melanoleuca)

During a 7 mo exhibit loan, diets of two juvenile female giant pandas (Ailuropoda melanoleuca) were monitored. Mineral [calcium (Ca), copper (Cu), phosphorus (P), potassium (K), zinc (Zn)] and vitamin (beta-carotene and total tocopherol) concentrations in the diet were quantified as well as in a serum sample obtained from one of these animals. Diets consumed by the pandas contained (dry matter basis): 0.82% Ca, 0.62% P, 1.05% K, 14.3 mg/kg Cu, 31.8 mg/kg Zn, 12.2 mg/kg beta-carotene, and 12 mg/kg total tocopherol. Serum values for these vitamins and minerals were within reported normal limits for the spectacled bear (Tremarctos ornatus). This diet appeared to provide adequate nutrition for maintenance and growth.

Analgesic electrical stimulation of the hypothalamic arcuate nucleus: tolerance and its cross-tolerance to 2 Hz or 100 Hz electroacupuncture

Focal electrical stimulation of the arcuate nucleus of the hypothalamus (ARH) for 5 min (1 session) produced a marked elevation of tail flick latency (TFL) to noxious heat in the pentobarbital-anesthetized rat. Repeated stimulation for a total of 11 sessions at 30 min intervals resulted in a gradual decline in the hypoalgesic action, and this tolerance may last for 7 days. Tolerance to the ARH analgesic stimulation reduced the analgesia produced by low (2 Hz) but not high (100 Hz) frequency electroacupuncture (EA); and tolerance to low frequency EA analgesia attenuated the ARH stimulation-produced analgesia without affecting high frequency EA analgesia. Alternatively, rats tolerant to high-frequency EA analgesia were still sensitive to either the ARH or low-frequency EA stimulation. These results suggest that the ARH stimulation and low-frequency EA administration produced analgesia via a common neural mechanism, supporting our hypothesis put forward previously that the ARH plays an important role in mediating low- but not high-frequency EA analgesia.

The arcuate nucleus of hypothalamus mediates low but not high frequency electroacupuncture analgesia in rats

Electrolytic, kainic acid or sham lesions were made in the arcuate nucleus of the hypothalamus (ARH) in female Wistar rats to investigate the putative role of the ARH in the organization of low (2 Hz) or high (100 Hz) frequency electroacupuncture (EA) analgesia. Both electrolytic and chemical lesions lead to an almost total suppression of the low frequency EA analgesia as measured 4 and 6 days following the surgical intervention, leaving high frequency EA analgesia unaffected. In sham-operated animals, the antinociceptive effect induced by low or high frequency EA was essentially intact. These data indicate that neurones of the ARH most likely play an important role in mediating low, but not high frequency EA analgesia.

Education of the Blind Population of Taiwan ROC and the Effects of International Agencies

The authors examine the impact of several agencies’ services, both domestic and international, for education of blind and visually impaired people in Taiwan. Findings show that although educational services and programs are available, those trained often find appropriate-level jobs scarce.

Free transplantation of venous network pattern skin flap

We report a patient treated by transplantation of a venous network pattern skin flap containing two superficial cutaneous veins. Through one of the veins, arterial blood passed into the capillaries, restoring circulation and ensuring survival of the flap.

Alkaloids of Nauclea officinalis

Five minor alkaloids were isolated from the stems of NAUCLEA OFFICINALIS Pierre ex Pitard: three new alkaloids named naucleficine ( 1), nauclefidine ( 2) and nauclefoline ( 3), and two known alkaloids 1-acetyl-beta-carboline and naucleidinal, along with vanillic acid.

Chemical Study of Alkaloids from Corydalis conspersa

From the whole plant of CORYDALIS CONSPERSA, four benzo[ C]-phenanthridine-type alkaloids were isolated. Three of these were identified as corynoline, acetylcorynoline and corynoloxine. The fourth is a new alkaloid, named consperine. Its structure, C (26)H (27)NO (7), has been established to be 6-acetonylacetylcorynoline on the basis of spectral data and chemical synthesis. The configuration of acetonyl group in consperine is also discussed.