Non-ionic surfactant based vesicles (niosomes) for non-invasive topical genetic immunization against hepatitis B

DNA vaccines are capable of eliciting both humoral as well as cellular immune responses. Liposomes have been widely employed for DNA delivery through topical route; however, they suffer from certain drawbacks like higher cost and instability. In present study, non-ionic surfactant based vesicles (niosomes) for topical DNA delivery have been developed. DNA encoding hepatitis B surface antigen (HBsAg) was encapsulated in niosomes. Niosomes composed of span 85 and cholesterol as constitutive lipids were prepared by reverse phase evaporation method. Prepared niosomes were characterized for their size, shape and entrapment efficiency. The immune stimulating activity was studied by measuring serum anti-HBsAg titer and cyokines level (IL-2 and IFN-gamma) following topical application of niosomes in Balb/c mice and results were compared with naked DNA and liposomes encapsulated DNA applied topically as well as naked DNA and pure recombinant HBsAg administered intramuscularly. It was observed that topical niosomes elicited a comparable serum antibody titer and endogenous cytokines levels as compared to intramuscular recombinant HBsAg and topical liposomes. The study signifies the potential of niosomes as DNA vaccine carriers for effective topical immunization. The proposed system is simple, stable and cost effective compared to liposomes.

Magnetization transfer MRI demonstrates spinal cord abnormalities in adrenomyeloneuropathy

BACKGROUND

In adrenomyeloneuropathy (AMN) conventional MRI detects only spinal cord atrophy in the late stages.

OBJECTIVE

To apply a magnetization transfer-weighted (MTw) imaging to patients with AMN and AMN-like syndrome in order to visualize and quantitatively assess the pathology of white matter tracts in the cervical spinal cord.

METHODS

MTw studies were conducted in nine men with AMN, eight symptomatic heterozygous women, and 10 age- and sex-matched controls and compared to the Expanded Disability Status Scale (EDSS) and quantitative tests of vibratory sense and postural sway. MTw data sets were obtained at the level of C1 to C3 using a three-dimensional gradient echo acquisition technique, these images were then standardized between subjects by using the in-slice CSF signal as a normalization reference, allowing a quantitative assessment of the MTw signal.

RESULTS

In contrast to conventional MRI, MTw images showed signal hyperintensities in the lateral and dorsal columns of all patients. The MT signal quantified in the dorsal column showed significant differences between patients with AMN, X-linked adrenoleukodystrophy heterozygotes, and controls. MT hyperintensity in the dorsal column correlated with EDSS, vibratory sense, and postural sway.

CONCLUSION

Magnetization transfer-weighted imaging is a sensitive modality for the visual and quantitative assessment of spinal cord pathology in adrenomyeloneuropathy, and is a potential tool for evaluation of new therapies.

Spectroscopic evidence of cerebral axonopathy in patients with "pure" adrenomyeloneuropathy

BACKGROUND

Adrenomyeloneuropathy (AMN) is the adult variant of X-linked adrenoleukodystrophy. The disease pathology is usually limited to spinal cord and peripheral nerves, and when this is the case, it is referred to as "pure" AMN. Histopathology shows cerebral involvement even in pure AMN; however, not much is known about the nature, extent, and clinical relevance of these findings.

OBJECTIVE

To investigate brain involvement in AMN patients with normal MRI, employing multislice MR spectroscopic imaging.

METHODS

Twelve men with pure AMN were compared with 19 age-matched healthy volunteers. Metabolite ratios (N-acetylaspartate [NAA]/choline [Cho], NAA/creatine [Cr], and Cho/Cr) were measured from seven brain regions. Global metabolite ratios were generated as an average of these seven regional ratios. The Expanded Disability Status Scale (EDSS) was used for neurologic evaluation.

RESULTS

The patients with AMN showed reduced global NAA/Cho (AMN 1.40 +/- 0.16 vs controls 1.75 +/- 0.34; p = 0.003)) and global NAA/Cr (AMN 2.32 +/- 0.13 vs controls 2.62 +/- 0.43; p = 0.03). Regionally, NAA/Cho was lowered in the internal capsule (AMN 1.30 +/- 0.20 vs controls 1.69 +/- 0.37; p = 0.002) and in parieto-occipital white matter (AMN 1.45 +/- 0.19 vs controls 1.78 +/- 0.55; p = 0.04). NAA/Cr was lowered in parieto-occipital white matter (AMN 2.34 +/- 0.31 vs controls 2.83 +/- 0.71; p = 0.04). EDSS demonstrated an inverse association with global NAA/Cr (r = -0.65, p = 0.02) and NAA/Cr in centrum semiovale (r = -0.73, p = 0.006) and in parieto-occipital white matter (r = -0.64, p = 0.02). Cho/Cr was not significantly elevated.

CONCLUSIONS

(1)H-MR spectroscopic imaging is able to detect biochemical abnormalities suggestive of axonal damage even in the brains of patients with pure adrenomyeloneuropathy. The axonopathy is most prominent in internal capsule and parieto-occipital white matter and may contribute to clinical disability.

The effect of use of pyridostigmine and requirement of vecuronium in patients with myasthenia gravis

CONTEXT

Patients with myasthenia gravis receive pyridostigmine, an anticholinesterase agent, as a part of therapy. These patients demonstrate a heightened sensitivity towards non-depolarising muscle relaxants. Continuing pyridostigmine till the day of the surgery or omitting it on the night before surgery could provide variable results with regards to the effect of vecuronium.

AIMS

Myographic evaluation of a dose of vecuronium in patients with myasthenia gravis on pyridostigmine therapy.

SETTING AND DESIGN

A randomised, double-blind, clinical study conducted in a teaching hospital.

SUBJECTS AND METHODS

Medically (oral pyridostigmine) well-controlled adult patients with myasthenia gravis who were posted for thymectomy, were randomly divided into two groups. Patients in Group 1 received their last dose of pyridostigmine on the night before surgery while those in Group 2 received even the morning dose of the drug on the day of surgery. Neostigmine (1-2 mg) intravenously was used as rescue medication. Vecuronium (0.01 mg/kg) was used for intubation and muscle relaxation during trans-sternal thymectomy and its effect was reversed using neostigmine and atropine.

RESULTS

Fourteen patients (7 in each group) belonging to both sexes were enrolled in the study. The intubating dose of vecuronium showed quicker onset time (155 sec or 2.7 min approx.) and peak effect (99% T1 suppression) in patients belonging to Group 1, and 3/7 (43%) complained of respiratory discomfort while waiting for surgery. By giving the morning dose of pyridostigmine (Group 2), an identical intubating dose of vecuronium showed relative resistance (peak effect-97% T1 suppression) and delayed onset time (198 sec approx.). However, the reversal was complete at the end of surgery in both the regimens.

CONCLUSIONS

Omission of the pyridostigmine dose on the day of surgery predisposed patients with myasthenia gravis to the possibility of respiratory discomfort and sensitivity to vecuronium. Continued administration significantly prolonged the onset time of vecuronium and the patients required a higher dose of vecuronium.

The role of sawdust in the removal of unwanted materials from water

Sawdust, a relatively abundant and inexpensive material is currently being investigated as an adsorbent to remove contaminants from water. Chemical substances including dyes, oil, toxic salts and heavy metals can be removed very effectively with the organic material. This article presents a brief review on the role of sawdust in the removal of contaminants. Studies on the adsorption of various pollutants by different sawdust materials are reviewed and the adsorption mechanism, influencing factors, favorable conditions, etc. discussed in this paper. Some valuable guidelines can be drawn for either scientific research or industrial design.

Modulation of radiation-induced protein kinase C activity by phenolics

Natural phenolic compounds were tested in vitro for their effect on the activity of protein kinase C (PKC) isolated from the liver cytosol and the particulate fraction of unirradiated mice and mice irradiated at 5 Gy. Following irradiation, the PKC activity was found to be increased in both cytosolic and particulate fractions. Curcumin, ellagic acid and quercetin were effective in inhibiting radiation-induced PKC activity. Curcumin and ellagic acid were found to be more inhibitory towards radiation-induced PKC activity, while quercetin was the least effective. Curcumin was found to inhibit the activated cytosolic and particulate PKC at very low concentrations. Activation of PKC is one of the means of conferring radioresistance on a tumour cell. Suppression of PKC activity by phenolics may be one of the means of preventing the development of radioresistance following radiotherapy.

Alternative pathways to prostate carcinoma activate prostate stem cell antigen expression

Prostate Stem Cell Antigen (PSCA) is a glycosylphosphatidylinositol-anchored cell surface protein that is expressed in normal human prostate and overexpressed in human prostate cancers. To test whether different pathways that generate prostate cancer would affect PSCA expression, a murine model system was developed. Monoclonal antibodies were generated against murine PSCA (mPSCA). mPSCA is expressed on approximately 20% of cells in normal prostate epithelium, and this number decreases with increasing age. In the transgenic adenocarcinoma of the mouse prostate (TRAMP) model of prostate cancer, tumors develop between 19 and 25 weeks of age. Murine PSCA was strongly expressed on approximately 60% of the cells of TRAMP tumors, at an age where the number of PSCA+ cells and the level of expression of PSCA is very low in the normal prostate. Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) +/- mice develop a number of different cancers, including prostate cancer. The incidence of prostate cancer is low and occurs after a relatively long latency. Fluorescence-activated cell sorter analysis of prostatic tissue from 11-18-month-old PTEN +/- mice showed elevated numbers of PSCA+ cells in the prostate, and immunohistochemical analysis showed high mPSCA expression in the tumors of these mice. Together, these results show that two distinct mechanisms of carcinogenesis lead to expression of a common target antigen.

Stereotactic radiosurgery for brain metastases: results and prognostic factors

This study was conducted to determine prognostic factors for tumor response and patient survival after stereotactic radiosurgery (SRS) for brain metastasis. Eighty-four patients with brain metastasis underwent SRS at a single institution. After fixation of the head with a stereotactic frame, computed tomography treatment planning was performed. The metastatic lesion was treated with multiple arcs to a median dose of 19 Gy. Forty-seven patients (56%) had a solitary brain lesion. Fifty-nine patients (70%) had evidence of extracranial disease at the time of SRS. The median survival duration from SRS was 7 months. Sixty-three percent of the patients had an objective radiographic response to SRS, which in turn was associated with superior central nervous system control. Age, collimator size, number of arcs, tumor location, and histology did not influence objective response rates. Patients who had a solitary lesion or who received treatment within 2 weeks after diagnosis were more likely to have an objective response than were those who did not (P < 0.05). Progressive brain disease accounted for 37% of the deaths. Nineteen patients (23%) had an in-field relapse. Four severe complications were attributed to SRS. This study confirms the role of SRS as an acceptable treatment option for patients with solitary or limited brain metastases. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 157-162 (2000).

Recovery of sperm production following radiation therapy for Hodgkin's disease after induction chemotherapy with mitoxantrone, vincristine, vinblastine, and prednisone (NOVP)

PURPOSE

The effect on human male fertility of radiotherapy following chemotherapy for the treatment of Hodgkin's disease (HD) is unknown. The impact of radiation therapy, given after mitoxantrone, vincristine, vinblastine, and prednisone (NOVP) chemotherapy, on sperm production is the focus of this study.

PATIENTS

Serial semen analyses were performed on 34 patients with HD Stages I-III before NOVP chemotherapy, after chemotherapy prior to radiation, and after radiation therapy. The most inferior radiation portals for patients were: mantle, 1 patient; paraaortic-spleen, 3 patients; upper abdomen, 24 patients; abdominal spade, 4 patients; and pelvic, 2 patients. Testicular radiation dose measurements were available for 20 of these patients.

RESULTS

Before the start of radiation, 90% of patients were normospermic. The magnitude of the decline in sperm counts was related to the measured testicular dose and/or radiation fields employed. The minimum postradiotherapy counts, expressed as a fraction of pretreatment counts, for the various treatment groups are as follows: paraaortic-spleen, 20%; upper abdomen, testicular dose < 30 cGy, 4%; upper abdomen, testicular dose 30-39 cGy, 0.9%; abdominal spade, 0.02%; and pelvis, 0%. The time to nadir of sperm counts averaged 4.5 months. Recovery to normospermic levels occurred in 96% of patients, with most recovering to that level within 18 months.

CONCLUSION

The effect of radiation following NOVP chemotherapy on sperm counts was no greater than would be expected with radiation therapy alone. In most patients, sperm counts recovered to levels compatible with normal fertility.

Localized primary non-Hodgkin lymphoma of the breast

A single institution's experience with the treatment of localized primary lymphoma of the breast (PLB) was analyzed to understand the natural history of this disease and to identify major prognostic factors and optimal treatment. A retrospective analysis of 23 previously untreated patients who met the strict criteria of PLB from 1972 through 1994 was undertaken. All pathologic materials were reviewed and classified by the Working Formulation. The Ann Arbor stages (AASs) were: IE, 17 patients; IIE, five patients; IV, one patients (bilateral breast involvement without distant metastasis). Pathologic findings were: low grade, two patients; intermediate grade, 18 patients (17 with diffuse large-cell lymphoma (DLCL)); high grade, two patients; and unclassifiable, one patient. The treatments after biopsy or mastectomy were: radiation alone, two patients; chemotherapy alone, six patients; and combined-modality therapy, 13 patients. Two patients had mastectomy alone. Overall survival (OS) and relapse-free survival (RFS) were calculated actuarially. Univariate analyses were performed with patient age, treatment modality, AAS, size of the primary tumor (T stage), and International Prognostic Index (IPI) for the 17 patients with DLCL to define prognostic factors. The median follow-up for the surviving patients was 78 months (range, 45-220 months). The 5-year OS and RFS were 74% and 73%, respectively for all 23 patients, and 65% and 70%, respectively, for the 17 patients with DLCL. Statistically significant factors for OS for DLCL were AAS and IPI. Statistically significant factors for RFS were AAS and T stage. With modern staging evaluation and multiagent combination chemotherapy, localized primary non-Hodgkin lymphoma of the breast, especially diffuse large-cell type, has a prognosis as favorable as that of other DLCL. Ann Arbor stage was a significant factor for both OS and RFS.

Tumor cells induce cytolytic T cells to a single immunodominant mutant peptide

Two different approaches have shown that cancers express mutant proteins that may be recognized as tumor-specific antigens. On the one hand, DNA sequences known to be mutant in tumor cells have been used to select for mutant peptides that induce tumor-specific T cells (the so-called "reverse immunologic" approach). On the other, T cells induced by vaccination with whole tumor cells have been used to identify tumor-specific mutations in proteins ("direct immunologic approach"). While both approaches generate tumor-specific T cells that can lyse cancer cells expressing the relevant mutant protein, the present study suggests that there may be crucial differences. Mutant epitopes originally defined from DNA sequences have so far been immunorecessive, and tumor cells themselves generally appear unable to induce specific CD8+ T cells that recognize the encoded mutant gene product. In contrast, we find that mutant epitopes identified by CD8+ T cells stimulated by immunization with whole tumor cells induce cytolytic T cells to such mutant peptides. In fact, much or all of the response appears to be to a single mutant octapeptide that seems to be immunodominant. One possible reason for the failure of immunorecessive antigens to induce a response may be the presence of lower amounts of the antigen in the cancer cell, but other mechanisms are possible as well. For example, in the host bearing a growing tumor, neither purified proteins nor peptides might be known; thus, only immunodominant unique antigens may be able to restimulate and activate tumor-specific memory T cells that localize in the tumor following active immunization.

Nonnasopharyngeal lymphoepithelioma of the head and neck

BACKGROUND

Lymphoepithelioma (squamous cell carcinoma with associated lymphoid stroma) commonly occurs in the nasopharynx, rarely at other sites. As a result, the clinical course and optimal treatment of nonnasopharyngeal lymphoepithelioma of the head and neck have not been well described. This retrospective study was undertaken to analyze the clinical course of the disease in patients treated at a single institution and to formulate recommendations for treatment based on that experience as well as results reported in the literature.

METHODS

Between 1950 and 1994, 34 patients with nonnasopharyngeal lymphoepithelioma of the head and neck were treated at the University of Texas M. D. Anderson Cancer Center. The patients' medical records were reviewed and their pathologic specimens evaluated. The primary tumor sites were: oropharynx (24 patients), salivary gland (4), laryngohypopharynx (4), and the maxillary sinus/nasal cavity (2). Assessed in accordance with the 1992 American Joint Committee Against Cancer TNM staging system, T classifications were TX-2, T1-7, T2-8, T3-10, and T4-7, and N classifications were N0-8, N1-5, N2-15, and N3-6. Treatment consisted of radiotherapy for 24 patients, excisional biopsy of the primary tumor followed by radiotherapy for 7 patients, and surgery for 3 patients. Of the patients treated with radiotherapy, neck dissections were performed on only two, both of whom had persistent lymph node masses after completing radiotherapy. The median dose delivered to the primary tumor was 65 gray (Gy) (range, 46-78 Gy). The median fraction size was 2.1 Gy (range, 1.6-3.2 Gy).

RESULTS

The 5-year actuarial disease specific survival and overall survival rates were 59% and 39%, respectively. The 5-year actuarial local control rate for all patients was 94%. For the irradiated patients, the 5-year regional control rates were 77% overall and 83% within the radiation field. The 5-year actuarial rate of distant metastasis for all patients was 30%. For patients who presented with and without regional adenopathy, the 5-year rates of distant metastasis were 36% and 12%, respectively (P = 0.27).

CONCLUSIONS

Nonnasopharygeal lymphoepithelioma is a radiosensitive disease. High rates of locoregional tumor control were achieved with radiotherapy at all head and neck sites. The main cause of treatment failure was distant metastasis, which occurred more frequently in patients with lymph node involvement. Radiotherapy is appropriate initial locoregional therapy for patients with this disease. Surgery should be reserved for patients who have persistent disease after completing radiotherapy. Systemic therapy is a reasonable approach for patients who present with regional adenopathy because they have a relatively high rate of distant metastasis.

Antigenic cancer cells grow progressively in immune hosts without evidence for T cell exhaustion or systemic anergy

One enigma in tumor immunology is why animals bearing malignant grafts can reject normal grafts that express the same nonself-antigen. An explanation for this phenomenon could be that different T cell clones react to the normal graft and the malignant cells, respectively, and only the tumor-reactive clonotypes may be affected by the growing tumor. To test this hypothesis, we used a T cell receptor transgenic mouse in which essentially all CD8(+) T cells are specific for a closely related set of self-peptides presented on the MHC class I molecule Ld. We find that the tumor expressed Ld in the T cell receptor transgenic mice but grew, while the Ld-positive skin was rejected. Thus, despite an abundance of antigen-specific T cells, the malignant tissue grew while normal tissue expressing the same epitopes was rejected. Therefore, systemic T cell exhaustion or anergy was not responsible for the growth of the antigenic cancer cells. Expression of costimulatory molecules on the tumor cells after transfection and preimmunization by full-thickness skin grafts was required for rejection of a subsequent tumor challenge, but there was no detectable effect of active immunization once the tumor was established. Thus, the failure of established tumors to attract and activate tumor-specific T cells at the tumor site may be a major obstacle for preventive or therapeutic vaccination against antigenic cancer.

Localized primary malignant lymphoma of bone

PURPOSE

A single institution's experience with the treatment of localized primary malignant lymphoma of bone (PLB) was analyzed to identify major prognostic factors, toxicity, and optimal treatment for this rare malignancy.

METHODS AND MATERIALS

A retrospective analysis of 45 previously untreated patients with Ann Arbor stage IE and IIE PLB from 1967 to 1992 was undertaken. All histopathologic material was reviewed. Irradiated patients received at least 40 Gy. Systemic chemotherapy was generally doxorubicin based. Overall survival (OS), progression free survival (PFS), and disease-specific survival (DSS) were calculated actuarially.

RESULTS

Histologically, there were 41 diffuse large cell, 2 diffuse mixed cell, 1 lymphocytic, and 1 lymphoblastic lymphomas. International Index scores were assessed on 43 patients. Thirty-six patients were treated with chemotherapy and radiation (CMT), five patients were treated with radiation only, and four patients were treated with chemotherapy only. Univariate analysis revealed significantly improved 5-year OS for those patients who had International Index scores of 0 vs. scores of 1 or 2 (85 vs. 53%, respectively, p = 0.004). Analysis failed to demonstrate a difference in OS, PFS, or DSS when comparing radiotherapy alone versus CMT, stage IE vs. stage IIE, or axial skeleton involvement vs. extremities.

CONCLUSION

The outcome of patients with PLB is relatively favorable in the era of CMT. Doses of radiation in the range of 46 Gy provide optimal local control with an acceptable rate of complications. The International Index is a valid prognostic tool for PLB.

The immunodominant antigen of an ultraviolet-induced regressor tumor is generated by a somatic point mutation in the DEAD box helicase p68

The genetic origins of CD8+ T cell-recognized unique antigens to which mice respond when immunized with syngeneic tumor cells are unknown. The ultraviolet light-induced murine tumor 8101 expresses an H-2Kb-restricted immunodominant antigen, A, that induces cytolytic CD8+ T cells in vivo A+ 8101 cells are rejected by naive mice while A- 8101 tumor cells grow. To identify the antigen H-2Kb molecules were immunoprecipitated from A+ 8101 cells and peptides were eluted by acid. The sensitizing peptide was isolated by sequential reverse-phase HPLC and sequenced using microcapillary HPLC-triple quadruple mass spectrometry. The peptide, SNFVFAGI, matched the sequence of the DEAD box protein p68 RNA helicase except for a single amino acid substitution, caused by a single nucleotide change. This mutation was somatic since fibroblasts from the mouse of tumor origin expressed the wild-type sequence. The amino acid substitution created an anchor for binding of the mutant peptide to H-2Kb. Our results are consistent with mutant p68 being responsible for rejection of the tumor. Several functions of p68, which include nucleolar assembly and inhibition of DNA unwinding, may be mediated through its IQ domain, which was altered by the mutation. This is the first description of a somatic tumor-specific mutation in the coding region of a nucleic acid helicase.

Synergy between T-cell immunity and inhibition of paracrine stimulation causes tumor rejection

During tumor progression, variants may arise that grow more vigorously. The fate of such variants depends upon the balance between aggressiveness of the variant and the strength of the host immunity. Although enhancing host immunity to cancer is a logical objective, eliminating host factors necessary for aggressive growth of the variant should also be considered. The present study illustrates this concept in the model of a spontaneously occurring, progressively growing variant of an ultraviolet light-induced tumor. The variant produces chemotactic factors that attract host leukocytes and is stimulated in vitro by defined growth factors that can be produced or induced by leukocytes. This study also shows that CD8+ T-cell immunity reduces the rate of tumor growth; however, the variant continues to grow and kills the host. Treatment with a monoclonal anti-granulocyte antibody that counteracts the infiltration of the tumor cell inoculum by non-T-cell leukocytes did not interfere with the CD8+ T-cell-mediated immune response but resulted in rejection of the tumor challenge, indicating a synergy between CD8+ T-cell-mediated immunity and the inhibition of paracrine stimulation.

Pollution and sanitary quality of river Narmada in relation to human use at Mandla

Study of physico-chemical characteristics and indicator bacterial population of Narmada river water at six different sites during summer, revealed extremely poor microbiological sanitary quality for human use. Free CO2 was found to be absent from all the sampling sites studied which indicates the trophogenic activity in the river water at Mandla. BOD value ranged from 1.0 to 2.5 mgl-1 and were less than the permissible limits of BOD in fresh waters i.e. 3-6 mgl-1.

Mastication and acid secretion

The gastric acid response and the buffer capacity of the stomach were measured in 30 control subjects and 22 duodenal ulcer patients in response to a masticatory (solid) and a non-masticatory (homogenized) meal having the same chemical composition. The peak acid output values were equal after a masticatory and after a non-masticatory diet in control subjects (masticatory 18.1 +/- 1.2, non-masticatory 15.7 +/- 1.3 mmol/hr) as well as in duodenal ulcer patients (masticatory 35.7 +/- 1.5, non-masticatory 33.7 +/- 1.1 mmol/hr). The buffer capacity of the stomach contents 1 hr after the meal was significantly greater after a masticatory diet than a non-masticatory diet in both controls (14.6 +/- 1.4 and 9.0 +/- 1.9 mmol) and in duodenal ulcer patients (9.5 +/- 1.5 and 7.5 +/- 1.2 mmol). Duodenal ulcer patients had a significantly lower buffer capacity compared with controls. Masticatory diets may play a part in protecting individuals from developing duodenal ulcer.

Effect of tea on gastric acid secretion

The gastric acid response to a 200-ml cup of tea was measured by in situ titration in 36 patients with duodenal ulcer (DU) and 56 without duodenal ulcer (controls). Tea resulted in an acid secretory response which was almost equal to that after a maximal dose (0.04 mg/kg) of histamine. The effect of tea was mainly due to its local chemical action on gastric mucosa. Tea without milk and sugar resulted in an acid response higher than that evoked by a maximal dose of histamine. The concentration of tea brew that had the greatest effect on gastric acid secretion was 15 g/200 ml, which was three times as much as that in a palatable cup of tea. Tea is a potent stimulant of gastric acid, and this can be reduced by adding milk and sugar.

Simultaneous measurement of gastric acid and duodenal alkali secretion by in situ titration in health and disease

We have devised a technique for simultaneously measuring the acid secretion into the stomach and alkali into the duodenum by in situ titration using a modification of the technique of Fordtran and Walsh. Using this technique, the results of acid and alkali secretion measured simultaneously were identical with those obtained using the conventional aspiration method on separate days. In response to stimulation with pentagastrin acid output was 17.2 +/- 1.4 vs 15.4 +/- 1.9 mmol/h and alkali response with secretin was 16.0 +/- 0.8 vs 14.4 +/- 1.5 mmol/h. The response to food was measured in 10 control subjects, 10 patients with duodenal ulcer, and 10 patients with pancreatitis. In controls, the acid and alkaline secretion were similar (15.8 +/- 1.7 vs 18.2 +/- 1.3 mmol/h), in patients with duodenal ulcer acid secretion was significantly greater than alkaline secretion (31.9 +/- 2.2 vs 21.9 +/- 1.7 mmol/h), and in patients with pancreatitis the alkali secretion was significantly less than acid (19.8 +/- 1.9 mmol/h acid vs 11.4 +/- 0.6 mmol/h alkali). It can, therefore, be concluded that in response to food the patients with duodenal ulcer are significant hypersecretors of acid (DU acid greater than DU alkali output) and patients with pancreatitis are significant hyposecretors of alkali (pancreatitis-alkaline output less than acid output) and normal subjects secrete equal amounts of acid and alkali.