Brief exposure to intermittent hypoxia increases erythropoietin levels in older adults.

Eight 4-min cycles of intermittent hypoxia represent the shortest hypoxic exposure to increase erythropoietin (EPO) levels in young adults. The impact of aging on the EPO response to a hypoxic stimulus remains equivocal. Thus, the objective of this study was to determine the effect of the same intermittent hypoxia protocol on EPO levels in older adults. Twenty-two participants (12 women, age: 53 ± 7 yr) were randomly assigned to an intermittent hypoxia group (IH, n = 11) or an intermittent normoxia group (IN, n = 11). Intermittent hypoxia consisted of eight 4-min cycles at a targeted oxygen saturation of 80% interspersed with normoxic cycles to resaturation. Air was made hypoxic by titrating nitrogen into a breathing circuit. Intermittent normoxia consisted of the same protocol, but nitrogen was not added to the breathing circuit. EPO levels were measured before and 4.5 h after the beginning of each protocol. Intermittent hypoxia lowered oxygen saturation to 82 ± 3%, which corresponded to a fraction of inspired oxygen of 10.9 ± 1.0%. There was a greater increase in EPO levels following intermittent hypoxia than intermittent normoxia (IH: 3.2 ± 2.2 vs. IN: 0.7 ± 0.8 mU/mL, P < 0.01). A single session of eight 4-min cycles of hypoxia increased EPO levels, the glycoprotein stimulating red blood cell production, in older adults. Exposure to intermittent hypoxia has therefore the potential to increase oxygen-carrying capacity in a population with reduced red blood cell volume.NEW & NOTEWORTHY We previously identified the shortest intermittent hypoxia protocol necessary to increase erythropoietin levels in young adults. The objective of this study was to determine whether the same intermittent hypoxia protocol increases erythropoietin levels in older adults. Eight 4-min bouts of hypoxia, representing a hypoxic duration of 32 min at a targeted oxygen saturation of 80%, increased erythropoietin levels in older adults, suggesting that exposure to intermittent hypoxia has the potential to increase oxygen-carrying capacity in an aging population.

Hypoxic preconditioning reduces endothelial ischemia-reperfusion injury in older adults.

Sudden blood flow restoration to an ischemic vessel paradoxically damages endothelial cells. Ischemic preconditioning, caused by repeated bouts of brief ischemia using local or remote cuff inflation before reperfusion, attenuates endothelial dysfunction following an ischemia-reperfusion injury in young adults but does not consistently protect endothelial function in older adults prone to ischemic events. Intermittent exposure to systemic hypoxemia, induced via brief bouts of breathing low levels of oxygen, attenuates endothelial dysfunction following an ischemia-reperfusion injury in young adults. The aim of this study was to determine whether systemic hypoxic preconditioning protects against ischemia-reperfusion injury in older adults. Twelve adults (five women, 57 ± 9 yr) participated in this randomized crossover trial. Endothelium-dependent vasodilation was assessed by brachial artery flow-mediated dilation using a semiautomated diagnostic ultrasound system before and after a 20-min blood flow occlusion that was preceded by either intermittent hypoxia, consisting of three 4-min hypoxic cycles at an oxygen saturation of 80% interspersed with 4-min room air cycles, or intermittent normoxia, consisting of three 4-min normoxic cycles separated by 4-min room air cycles. When preceded by intermittent normoxia, ischemia-reperfusion injury reduced flow-mediated dilation by 4.1 ± 2.6% (6.5 ± 1.7 to 2.4 ± 1.7%). In contrast, flow-mediated dilation was reduced by 2.0 ± 1.5% when ischemia-reperfusion injury was preceded by intermittent hypoxia (5.6 ± 1.7 to 3.6 ± 2.3%). In conclusion, hypoxic preconditioning significantly attenuated the reduction in brachial artery flow-mediated dilation induced by an ischemia-reperfusion injury in older adults at greater risk for ischemic events.

The extracellular matrix glycoprotein tenascin-X regulates peripheral sensory and motor neurones.

KEY POINTS: Tenascin-X (TNX) is an extracellular matrix glycoprotein with anti-adhesive properties in skin and joints. Here we report the novel finding that TNX is expressed in human and mouse gut tissue where it is exclusive to specific subpopulations of neurones. Our studies with TNX-deficient mice show impaired defecation and neural control of distal colonic motility that can be rescued with a 5-HT4 receptor agonist. However, colonic secretion is unchanged. They are also susceptible to internal rectal intussusception. Colonic afferent sensitivity is increased in TNX-deficient mice. Correspondingly, there is increased density of and sensitivity of putative nociceptive fibres in TNX-deficient mucosa. A group of TNX-deficient patients report symptoms highly consistent with those in the mouse model. These findings suggest TNX plays entirely different roles in gut to non-visceral tissues - firstly a role in enteric motor neurones and secondly a role influencing nociceptive sensory neurones Studying further the mechanisms by which TNX influences neuronal function will lead to new targets for future treatment. ABSTRACT: The extracellular matrix (ECM) is not only an integral structural molecule, but is also critical for a wide range of cellular functions. The glycoprotein tenascin-X (TNX) predominates in the ECM of tissues like skin and regulates tissue structure through anti-adhesive interactions with collagen. Monogenic TNX deficiency causes painful joint hypermobility and skin hyperelasticity, symptoms characteristic of hypermobility Ehlers Danlos syndrome (hEDS). hEDS patients also report consistently increased visceral pain and gastrointestinal (GI) dysfunction. We investigated whether there is a direct link between TNX deficiency and GI pain or motor dysfunction. We set out first to learn where TNX is expressed in human and mouse, then determine how GI function, specifically in the colon, is disordered in TNX-deficient mice and humans of either sex. In human and mouse tissue, TNX was predominantly associated with cholinergic colonic enteric neurones, which are involved in motor control. TNX was absent from extrinsic nociceptive peptidergic neurones. TNX-deficient mice had internal rectal prolapse and a loss of distal colonic contractility which could be rescued by prokinetic drug treatment. TNX-deficient patients reported increased sensory and motor GI symptoms including abdominal pain and constipation compared to controls. Despite absence of TNX from nociceptive colonic neurones, neuronal sprouting and hyper-responsiveness to colonic distension was observed in the TNX-deficient mice. We conclude that ECM molecules are not merely support structures but an integral part of the microenvironment particularly for specific populations of colonic motor neurones where TNX exerts functional influences.

The effect of protein supplementation on body muscle mass and fat mass in post-bariatric surgery: a randomized controlled trial (RCT) study protocol.

BACKGROUND: Severe weight loss through means of bariatric surgery has been associated with loss of muscle mass due to lack of absorption of protein. The aim of this RCT is to investigate the effectiveness of protein supplementation in reducing the risk of developing protein malnutrition and muscle wasting in post-bariatric surgery patients in Qatar. METHODS AND ANALYSIS: The study was based at the Department of bariatric and metabolic surgery, Doha metropolitan and regional areas. It is envisaged that approximately 160 post-bariatric surgery patients will be randomized and followed up for 6 months. These will be males and females obese (BMI >35) Qatari patients between the aged 18-60 years. Subjects with renal or liver disease and those with past history of bariatric surgery will be excluded. By the completion of the trial, patients who took less than 80% of the supplement will be further excluded from the final analysis. Protein supplement (Cubitan,Protein, Nutricia, Netherlands) that contain daily intake of 20 g of protein to be taken orally 3 times a day throughout the study period. The placebo group will receive identical ampule containing zero-protein with exact instructions as per the intervention group. Body weight, muscle and fat mass, total protein, albumin, vit B12, Magnesium and Zinc will be measured at baseline and every follow up/study visit. Study variables will be compared between the 2 groups at different stages of the trial, including baseline, using Sample T-test (paired and unpaired) and the significance level will be confirmed with the 95% confidence interval with alpha error set to 0.05. ETHICS AND DISSEMINATION: Protein supplementation for post-bariatric patients is not yet a standard procedure at Hamad Medical Corporation in Qatar and requires an RCT to establish evidence-based clinical practice guidelines. This study was approved by the Hamad Medical Corporation IRB and MRC committees (approval no. 16433/16). TRIAL REGISTRATION: ClinicalTrials.gov NCT03147456 (registration date: 18 April 2017). STRENGTHS AND LIMITATIONS OF THIS STUDY: One major strength of our study is that our population is a distinctive population (Qatari Obese patients) where results from international studies may not apply to the local and unique context. A local study like ours will provide healthcare providers in Qatar an opportunity to ensure good clinical practice and healthy and sustainable weight loss following bariatric surgery.The well-designed double-blinded RCT will almost certainly provide us with the evidence-based clinical practice guideline that we seek as health professionals.One limitation of our study is the slight discrepancy in caloric content of the intervention and the placebo (250 cal and 100 cal, respectively). However, it is the intervention that has the higher caloric content, in which case it may not influence the results in the direction of our hypothesis that protein supplementation leads to lower fat mass and higher muscle mass.Another limitation is that the use of the intervention and the placebo are not objectively measured. However, all efforts will be made to ensure compliance and reporting of consumption of products.A third limitation could be loss to follow up. Participants may cease to participate, particularly, once they have lost "sufficient' weight and gained the fitness to consume any type of foods they desire. This is common in late stages of post-bariatric surgery (beyond 3 months). We feel that this may be a challenge, particularly in reference to our specific population. However, such findings albeit negative, should serve in improving the clinical practice delivered by healthcare providers.

Type 1 diabetic patients with peripheral neuropathy have pan-enteric prolongation of gastrointestinal transit times and an altered caecal pH profile.

AIMS/HYPOTHESIS: We hypothesised that type 1 diabetic patients with established diabetic sensorimotor polyneuropathy (DSPN) would have segmental and/or pan-enteric dysmotility in comparison to healthy age-matched controls. We aimed to investigate the co-relationships between gastrointestinal function, degree of DSPN and clinical symptoms. METHODS: An observational comparison was made between 48 patients with DSPN (39 men, mean age 50 years, range 29-71 years), representing the baseline data of an ongoing clinical trial (representing a secondary analysis of baseline data collected from an ongoing double-blind randomised controlled trial investigating the neuroprotective effects of liraglutide) and 41 healthy participants (16 men, mean age 49 years, range 30-78) who underwent a standardised wireless motility capsule test to assess gastrointestinal transit. In patients, vibration thresholds, the Michigan Neuropathy Screening Instrument and Patient Assessment of Upper Gastrointestinal Symptom questionnaires were recorded. RESULTS: Compared with healthy controls, patients showed prolonged gastric emptying (299 ± 289 vs 179 ± 49 min; p = 0.01), small bowel transit (289 ± 107 vs 224 ± 63 min; p = 0.001), colonic transit (2140, interquartile range [IQR] 1149-2799 min vs 1087, IQR 882-1650 min; p = 0.0001) and whole-gut transit time (2721, IQR 1196-3541 min vs 1475 (IQR 1278-2214) min; p < 0.0001). Patients also showed an increased fall in pH across the ileocaecal junction (-1.8 ± 0.4 vs -1.3 ± 0.4 pH; p < 0.0001), which was associated with prolonged colonic transit (r = 0.3, p = 0.001). Multivariable regression, controlling for sex, disease duration and glycaemic control, demonstrated an association between whole-gut transit time and total GCSI (p = 0.02). CONCLUSIONS/INTERPRETATION: Pan-enteric prolongation of gastrointestinal transit times and a more acidic caecal pH, which may represent heightened caecal fermentation, are present in patients with type 1 diabetes. The potential implication of delayed gastrointestinal transit on the bioavailability of nutrition and on pharmacotherapeutic and glycaemic control warrants further investigation. TRIAL REGISTRATION: EUDRA CT: 2013-004375-12.

Caecal pH is a biomarker of excessive colonic fermentation.

AIM: To ascertain whether caecal pH is different in patients with irritable bowel syndrome (IBS), whose primary symptoms are bloating and distension, to healthy controls. METHODS: Motility and pH data were reviewed from 16 patients with Rome III defined IBS and 16 healthy controls, who had undergone a wireless motility capsule (WMC) study using a standardized protocol. Motility measures were anchored around known anatomical landmarks as identified by compartmental pH changes. Sixty-minute epochs were used to quantify antral, duodenal, ileal, caecal and distal colonic contractility. The maximum and minimum pH was measured either side of the ileo-caecal junction. RESULTS: No differences were seen in motility parameters, compartmental transit times or maximal ileal pH between the two groups. Caecal pH was significantly lower in patients compared to controls (5.12 ± 0.05 vs 6.16 ± 0.15, P < 0.0001). The ileal:caecal Δchange was greater in patients than controls (-2.63 ± 0.08 vs -1.42 ± 0.11, P < 0.0001). There was a significant correlation between caecal pH and right colonic contractility (r = 0.54, P = 0.002). CONCLUSION: Patients with bloating and distension have a lower caecal pH compared to controls. The measurement of caecal pH using the WMC provides a quantifiable biomarker of fermentation potentially identifying those patients that may preferentially benefit from antibiotic or dietary interventions.

Mixed methods pilot study of sharing behaviors among waterpipe smokers of rural Lao PDR: implications for infectious disease transmission.

To date, the sharing behaviors associated with the homemade tobacco waterpipe used in rural areas of the Western Pacific Region have not been studied. Evidence from studies of manufactured waterpipes raises the possibility of infectious disease transmission due to waterpipe sharing. The objective of our pilot study in rural Lao People's Democratic Republic (PDR) was to identify and measure the prevalence of waterpipe sharing behaviors. We first conducted ethnographic studies to investigate waterpipe-smoking behaviors. These findings were then used to develop an interviewer-administered household survey that was used in a sampling of waterpipe smokers from three villages of the Luang Namtha province of Lao PDR (n = 43). Sampled waterpipe smokers were predominantly male (90.7%), older (mean age 49, SD 13.79), married (95.4%), farmers (78.6%), and had completed no primary education. Pipes were primarily made from bamboo (92.9%). Almost all (97.6%) smokers were willing to share their pipe with others. At the last time they smoked, smokers shared a pipe with at least one other person (1.2 ± 0.5 persons). During the past week, they had shared a pipe with five other persons (5.2 ± 3.8 persons). The high prevalence of sharing behaviors among waterpipe smokers in rural Southeast Asia raises the possibility that this behavior provides important and unmeasured social network pathways for the transmission of infectious agents.

Accurate localization of a fall in pH within the ileocecal region: validation using a dual-scintigraphic technique.

Stereotypical changes in pH occur along the gastrointestinal (GI) tract. Classically, there is an abrupt increase in pH on exit from the stomach, followed later by a sharp fall in pH, attributed to passage through the ileocecal region. However, the precise location of this latter pH change has never been conclusively substantiated. We aimed to determine the site of fall in pH using a dual-scintigraphic technique. On day 1, 13 healthy subjects underwent nasal intubation with a 3-m-long catheter, which was allowed to progress to the distal ileum. On day 2, subjects ingested a pH-sensitive wireless motility capsule labeled with 4 MBq (51)Chromium [EDTA]. The course of this, as it travelled through the GI tract, was assessed with a single-headed γ-camera using static and dynamic scans. Capsule progression was plotted relative to a background of 4 MBq ¹¹¹Indium [diethylenetriamine penta-acetic acid] administered through the catheter. Intraluminal pH, as recorded by the capsule, was monitored continuously, and position of the capsule relative to pH was established. A sharp fall in pH was recorded in all subjects; position of the capsule relative to this was accurately determined anatomically in 9/13 subjects. In these nine subjects, a pH drop of 1.5 ± 0.2 U, from 7.6 ± 0.05 to 6.1 ± 0.1 occurred a median of 7.5 min (1-16) after passage through the ileocecal valve; location was either in the cecum (n = 5), ascending colon (n = 2), or coincident with a move from the cecum to ascending colon (n = 2). This study provides conclusive evidence that the fall in pH seen within the ileocolonic region actually occurs in the proximal colon. This phenomenon can be used as a biomarker of transition between the small and large bowel and validates assessment of regional GI motility using capsule technology that incorporates pH measurement.

Insect bite-like reaction associated with mantle cell lymphoma: clinicopathological, immunopathological, and molecular studies.

A cutaneous eruption simulating insect bites has been repeatedly described in association with chronic lymphocytic leukemia (CLL). It was only rarely described with mantle cell lymphoma (MCL). Our study was performed to elucidate the clinical, histologic, immunopathological, and molecular characteristics of insect bite like reaction (IBLR) associated with MCL. The clinical presentation and histologic findings in 3 IBLR cases associated with MCL were found to be similar to 3 IBLR cases associated with CLL. The eruptions consisted of itchy erythematous papules, nodules, plaques, and vesicles. Non-vesicular lesions were characterized histologically by normal or mildly spongiotic epidermis. Vesicular lesions were characterized by marked spongiosis and intraepidermal spongiotic vesicles containing eosinophils, or marked subepidermal edema occasionally leading to a dermoepidermal separation. Most of the lesions were characterized by superficial and mid dermal to deep perivascular and interstitial, and occasionally periadnexal, inflammatory-cell infiltrate consisting of mononuclear cells and eosinophils. The densities of the infiltrates varied and the inflammatory-cell infiltrate extended often into the fat lobules. Neutrophils and nuclear dust were found more frequently and abundantly in the IBLR lesions associated with MCL. Immunophenotyping, direct immunofluorescence (DIF) tests, and IgH gene rearrangement studies were performed in the lesions associated with MCL only. The majority of the infiltrating lymphocytes were CD3+, CD5+ and CD43+, more CD4+ than CD8+, and only a small minority was CD20+. The cells did not stain for bcl-1 protein and CD30, and with no evidence of clonality. The DIF test result was negative. The IBLR eruption associated with MCL resembles clinically and histologically IBLR associated with CLL. The eruption seems to be reactive rather than neoplastic, because there is no evidence of MCL involvement in the skin lesions.

Laparoscopic management of non-communicating rudimentary horn in a dysmenorrheic and infertile patient.

A case of laparoscopic excision of non-communicating rudimentary horn. The anatomical features of this case were unique. A 19-year-old nulligravida presented with severe dysmenorrhea and primary infertility. Hysterosalpingogram revealed a left uterine horn that had a solitary patent tube. Magnetic resonance imaging showed a left unicornuate uterus continuous with the cervix and the vagina, and a rudimentary right uterine horn. This confirmed the diagnosis of non-communicating cavitated right rudimentary horn. At laparoscopy the patient had stage III endometriosis, and non-communicating right rudimentary horn, which was attached to the unicornuate uterus by a long fibrous band. The rudimentary horn was freed from the pelvic side wall, excised and removed laparoscopically with no complication.

Liver and circulating NK1.1(+)CD3(-) cells are increased in infection with attenuated Salmonella typhimurium and are associated with reduced tumor in murine liver cancer.

An attenuated (DeltacyA, Deltacrp) strain of Salmonella typhimurium (chi4550) containing a gene for human IL-2 (chi4550pIL2) reduces hepatic tumor burden when orally inoculated into mice with liver cancer; however, wild-type S. typhimurium is also associated with cancer regression. Therefore, experiments were designed to clarify the invasiveness and the anti-tumor properties of three strains of S. typhimurium. S. typhimurium chi4550pIL2, chi4550, or wild type (WT) was incubated with mature Caco-2 and HT-29 enterocytes, and S. typhimurium internalization was assessed. For infectivity experiments, mice were orally inoculated with saline or 10(9)S. typhimurium chi4550pIL2, chi4550, or WT; 48 h later mice were sacrificed for analysis of cecal bacteria and S. typhimurium translocation to mesenteric lymph nodes. For experiments involving tumor implantation, four groups were studied: saline control, tumor alone, chi4550pIL2+tumor, and chi4550+tumor. Mice were orally inoculated with saline or S. typhimurium and underwent laparotomy 24 h later with 5 x 10(4) MCA38 murine adenocarcinoma cells injected into the spleen. On day 14, liver tumors were counted and peripheral blood and hepatic lymphocyte populations were analyzed by FACScan. Attenuated S. typhimurium exhibited decreased internalization by cultured enterocytes and decreased infectivity after oral inoculation. Mice treated with chi4550pIL2 or chi4550 had fewer liver tumors and increased populations of hepatic and circulating NK1.1(+)CD3(-) lymphocytes compared to mice treated with saline (P < 0.01). These data suggest that attenuated S. typhimurium may have an application as an anti-tumor agent.

The effect of antiviral therapy on t(14;18) translocation and immunoglobulin gene rearrangement in patients with chronic hepatitis C virus infection.

The mechanism of lymphomagenesis of hepatitis C virus (HCV)-related B-cell lymphoma is unknown. Recently, it has been suggested that HCV may induce B-cell clonal proliferation and t(14;18) translocation in patients chronically infected with the virus. Thus, this study investigated the effect of antiviral treatment on immunoglobulin heavy-chain gene (IgH) rearrangement and t(14;18) translocation in HCV infected patients. Twenty-nine patients with chronic HCV infection were studied in whom IgH rearrangement and/or t(14;18) translocation were previously detected. The IgH rearrangement (FR3/JH) and t(14;18) translocation (MBR bcl2-JH) were detected in peripheral blood mononuclear cells by polymerase chain reaction. Fifteen of 29 patients (8 with IgH rearrangement, 6 with t(14;18) translocation, and 1 with both) were treated with either interferon-alpha or by combination therapy with interferon and ribavirin for 6 to 12 months. IgH rearrangement became negative in 7 of 9 treated patients compared with only 1 of 8 of nontreated patients (P <.02). The t(14;18) translocation became negative in 6 of 7 treated patients compared with 1 of 6 nontreated patients (P =.03). Disappearance of IgH rearrangement or t(14;18) translocation was strongly associated with virologic response to treatment. Two t(14;18)+ patients developed B-cell lymphoma during follow-up. Antiviral treatment appears to be effective in eliminating the clonal proliferation of B cells in patients with chronic HCV infection and may prevent the subsequent development of lymphoma. The mechanism can be related to a direct effect of interferon-alpha on the proliferating clone or to an indirect effect by eradicating the antigenic stimulus.

bcl-2 and immunoglobulin gene rearrangement in patients with hepatitis C virus infection.

An association between chronic hepatitis C virus (HCV) infection and clonal proliferation of B cells, including B cell lymphoma, has recently been demonstrated. However, the mechanism of malignant transformation is still unknown. It has been shown that B cells from patients with type II mixed cryoglobulinaemia (MC), strongly express the antiapoptotic bcl-2 oncogene product. Therefore, we investigated a possible mechanism of lymphomagenesis, the occurrence of bcl-2 and immunoglobulin gene rearrangement (IgH) in HCV-infected patients. Three groups of patients were studied: (1) 44 patients with HCV and MC (anti-HCV and HCV RNA positive); (2) 59 patients with chronic HCV infection without MC; (3) 50 patients with chronic liver disease (CLD) not related to HCV infection. The t(14;18) translocation (MBR bcl-2-JH) and IgH rearrangement (FR3/JH) were detected by polymerase chain reaction (PCR) in peripheral mononuclear cells. bcl-2 translocation was detected in 17/44 (39%), 7/59 (12%) and in none of the patients of groups 1, 2 and 3 respectively (P < 0.01). Monoclonal IgH rearrangement was detected in 15/44 (34%), 5/59 (8.5%) and 2/50 (4%) patients of groups 1, 2 and 3 respectively (P < 0.05). HCV-infected patients had a higher prevalence of monoclonal IgH rearrangement and bcl-2 translocation than patients with CLD of other aetiologies. These data suggest that HCV may play a role in the multistep mechanism of lymphomagenesis by inducing clonal proliferation of B cells and inhibition of apoptosis.

The Candida albicans INT1 gene facilitates cecal colonization in endotoxin-treated mice.

Increased intestinal colonization with Candida albicans is believed to be a major predisposing factor to systemic candidiasis. Previous evidence has implicated the C. albicans INT1 gene in hyphal development, epithelial adherence, and mouse virulence. The effect of INT1 on mouse cecal colonization was measured using a parent strain (CAF2, INT1/INT1), an int1 deletion homozygote (CAG3, int1/int1), and a heterozygous reintegrant (CAG5, int1/int1 + INT1). Forty-eight hours after oral inoculation of 10(7) C. albicans into normal mice, only low numbers of each strain were recovered from the cecal flora. In mice pretreated with oral bacitracin/streptomycin, cecal colonization of each C. albicans strain was increased compared to the corresponding strain inoculated into untreated mice, with the CAF2 parent strain greater (P < 0.01) than the two mutant strains, and with the heterozygous and homozygous mutants not different from each other. In mice pretreated with parenteral lipopolysaccharide (LPS), in addition to oral antibiotics, numbers of cecal CAF2, CAG5, and CAG3 were increased (P < 0.01) compared to the corresponding strain inoculated into mice treated with antibiotics alone. In LPS-treated mice, numbers of cecal C. albicans CAF2 (INT1/INT1) were greater (P < 0.05) than C. albicans CAG3 (int1/int1). Thus, parenteral LPS had an additive effect on C. albicans cecal colonization in antibiotic-treated mice, and the presence of two functional copies of the INT1 gene appeared to facilitate colonization in both antibiotic-treated mice and in mice treated with antibiotics plus parenteral endotoxin.

Unilesional mycosis fungoides: a study of seven cases.

BACKGROUND: Unilesional mycosis fungoides (MF) is a rare variant of cutaneous T-cell lymphoma (CTCL), characterized by a solitary lesion clinically and by histopathological features indistinguishable from those of MF, and typically having a benign course. OBJECTIVE: To describe the clinicopathological features of a series of patients with unilesional MF. METHODS: The records of cases of unilesional MF identified during a 10-year period in two medical departments were reviewed. RESULTS: There were 7 patients: 6 males, 1 female; mean age at the time of diagnosis: 32 years; age range: 12-58 years; 3 were below the age of 18 years. The mean pretherapy follow-up period was 9 years (range: 2-20 years). In 5 patients, the eruption consisted of a characteristic patch or plaque of MF located on the trunk or upper extremity; in 2 it was atypical - in 1, a hypopigmented patch, and in 1, a plaque indistinguishable from MF-associated follicular mucinosis. Histopathologically all the lesions exhibited features characteristic of MF, with CD3+ lymphoid cells. In 6 cases (with available fresh frozen tissue) there was a predominance of CD3+ CD4+ cells; in 1 of 5 there was deletion of CD7, and in 3 of 5 there was an overexpression of IL-2 receptor. T-cell receptor gamma gene rearrangement was found in 1 of 4 cutaneous lesions tested; in 2 cases it was found in the blood but not in the skin. Treatment modalities included localized electron beam, excision, topical nitrogen mustard or topical steroids and sunbathing, resulting in all cases in a sustained complete clinical response. In 1 patient, however, there were 2 local recurrences and in yet another patient there was distant cutaneous spread 3.5 years after therapy. CONCLUSIONS: Unilesional MF is a rare variant of CTCL, has heterogeneous clinical manifestations and can affect any age group, including children. The histopathological and immunophenotypical features are in general indistinguishable from those observed in multilesional MF. Although it is a unifocal event, there may occasionally be cutaneous spread with the appearance of noncontiguous lesions, even a long time after therapy. Whether all cases represent minimal-stage IA MF or whether some are actually T-cell pseudolymphoma remains to be clarified.

Follicular cutaneous T-cell lymphoma: a clinicopathological study of nine cases.

Nine patients with follicular cutaneous T-cell lymphoma (CTCL), a recently described variant of lymphoma, are presented. On the basis of clinical manifestations and disease course, three groups of patients were distinguished: (i) two patients with follicular CTCL not associated with conventional lesions of mycosis fungoides (MF) and showing no evolution towards MF in follow-up periods of 3 and 6 years; (ii) one patient with follicular CTCL that evolved into conventional MF within 3 years; (iii) six patients showing conventional MF lesions either before or concurrently with the follicular lesions and thus representing follicular CTCL of the true MF type. The follicular lesions included hair-devoid patches or plaques with spiky hyperkeratotic papules (four patients), keratosis pilaris-like lesions (four), comedo-like lesions (four), follicular papules with alopecia (three) and milia-like lesions (three). Histopathological examination showed perifollicular and intrafollicular lymphocytes, without mucin deposition and with minimal or no involvement of the overlying epidermis. Significant syringotropism was also observed in three cases. Immunohistochemical analysis showed the predominance of CD4 + T cells, deletion of CD7 in some cases, Ki-67 + lymphocytes confined mainly to the follicular epithelium, and expression of keratinocyte intercellular adhesion molecule-1 exclusively in the hair follicle. T-cell receptor gamma gene rearrangement was positive in the one case studied from each group. Different treatment modalities were employed, the most commonly used as monotherapy being phototherapy: psoralen ultraviolet A in four patients, two of whom showed a complete clinical and histopathological remission, and ultraviolet B in one patient, who showed a complete remission (both clinical and histopathological). This study indicates that follicular CTCL is more common than reflected in the literature, has heterogeneous clinical manifestations, and is either an expression of or closely related to MF. The influence of the follicular involvement on the therapeutic response remains to be clarified. However, our therapeutic experience clearly suggests that some patients with follicular CTCL can benefit from phototherapy.

Immunophenotyping and T-cell receptor gamma gene rearrangement analysis as an adjunct to the histopathologic diagnosis of mycosis fungoides.

BACKGROUND: The histopathologic diagnosis of mycosis fungoides (MF) may be difficult. OBJECTIVE: Our purpose was to evaluate the role of immunophenotyping and T-cell receptor (TCR) gene rearrangement studies as an adjunct to the histopathologic diagnosis of MF. METHODS: Immunohistochemical studies with antibodies to CD4, CD5, CD7, and CD8 and TCR gamma gene rearrangement analysis with a polymerase chain reaction were performed on fresh-frozen material of patients with "classic" histology of MF, "inconclusive" histology, and benign inflammatory dermatoses. RESULTS: Clonal TCR gamma gene rearrangements were found in 11 of 16 (69%) of classic MF cases, in 3 of 19 (16%) of inconclusive cases, and in none of the 12 inflammatory dermatoses cases (P < .05 and P < .001, respectively). Only the mean CD7 counts were statistically significantly different between these 3 groups (MF < inconclusive < inflammatory). CONCLUSION: Inconclusive histology is probably a heterogeneous group in which CD7 counts and TCR gamma gene rearrangement studies might help to differentiate the MF cases from the benign cases.

Molecular follow-up of disease progression and interferon therapy in chronic myelocytic leukemia.

We previously reported that the abl promoter (Pa) undergoes de novo DNA methylation in the course of chronic myelocytic leukemia (CML). The clinical implications of this finding are the subject of the present study in which samples of CML patients, including a group treated with interferon alpha (IFNalpha) were surveyed. The methylation status of the abl promoter was monitored by polymerase chain reaction (PCR) amplification of the Pa region after digestion with several site-methylation sensitive restriction enzymes. Some 74% of the DNA samples from blood and marrow drawn in the chronic phase were nonmethylated, similar to control samples from non-CML patients. The remaining 26% were partially methylated in the abl Pa region. The latter samples were derived from patients who were indistinguishable from the others on the basis of clinical presentation. Methylated samples were mostly derived from patients known to have a disease of longer duration (26 months v 7.5 months, P = .01). Samples of 30 IFNalpha-treated patients were sequentially analyzed in the course of treatment. Fifteen patients with no evidence of Pa methylation before treatment remained methylation-free. The remainder, who displayed Pa methylation before treatment, reverted to the methylation-free status. The outcome is attributed to IFNalpha therapy, as the Pa methylation status was not reversed in any of the patients treated with hydroxyurea. Methylation of the abl promoter indicates a disease of long-standing, most likely associated with a higher probability of imminent blastic transformation. It appears to predict the outcome of IFNalpha therapy far better than the cytogenetic response.

Differential expression during embryogenesis of three genes clustered in the Ras1 region of Drosophila melanogaster.

Transcription mapping and nucleotide sequence analysis reveal that the genomic region of the Drosophila Ras1 gene contains a cluster of three closely localized genes. A gene termed Rlb1 is located nearby and upstream of Ras1, and is oriented in the opposite polarity relative to Ras1. In addition, a third gene termed Rlc1, is found at a very close proximity downstream to Rlb1. Ras1, the homologue of the human transforming ras genes, has been shown to be active in the posterior termini of the Drosophila embryo and in the eye imaginal disc in pathways of cell fate determination. We demonstrate that during embryogenesis Ras1 transcripts are restricted mainly to the embryonic central nervous system, suggesting that the gene product also may have a role in these nerve cells. Rlb1 encodes for a novel, lysine-rich basic protein. It is expressed mainly in the developing midgut and in the somatic mesoderm. Rlc1 also encodes for a novel, basic protein. The expression of Rlc1 during embryogenesis is similar, but not identical, to the expression pattern detected for Ras1. The vertebrate p21Ras proteins are bound to the inner face of the cell membrane. Ras1, the Drosophila homologue of p21, and the Rlb1 protein, are also non-cytoplasmic, membranous proteins. Rlb1 is found in the cell membrane of larval midgut epithelial cells. In addition, Rlb1 is detected in the nuclei of these cells, and in the nuclei of the midgut imaginal cells.