Absence of 3a0 charge density wave order in the infinite-layer nickelate NdNiO2

A hallmark of many unconventional superconductors is the presence of many-body interactions that give rise to broken-symmetry states intertwined with superconductivity. Recent resonant soft X-ray scattering experiments report commensurate 3a0 charge density wave order in infinite-layer nickelates, which has important implications regarding the universal interplay between charge order and superconductivity in both cuprates and nickelates. Here we present X-ray scattering and spectroscopy measurements on a series of NdNiO2+x samples, which reveal that the signatures of charge density wave order are absent in fully reduced, single-phase NdNiO2. The 3a0 superlattice peak instead originates from a partially reduced impurity phase where excess apical oxygens form ordered rows with three-unit-cell periodicity. The absence of any observable charge density wave order in NdNiO2 highlights a crucial difference between the phase diagrams of cuprate and nickelate superconductors.

Nutrient Composition, Physicobiochemical Analyses, Oxidative Stability and Antinutritional Assessment of Abundant Tropical Seaweeds from the Arabian Sea

Foods enriched with nutritional compounds and biological activities, especially antioxidants, are considered healthier for human and/or animal consumption. Seaweeds are rich sources of biologically active metabolites and are used as functional foods. In this study, proximate compositions, physicobiochemical characteristics and oil oxidative stability were analyzed for 15 abundant tropical seaweeds (four green-Acrosiphonia orientalis, Caulerpa scalpelliformis, Ulva fasciata, Ulva lactuca; six brown-Iyengaria stellata, Lobophora variegate, Padina boergesenii, Sargassum linearifolium, Spatoglossum asperum, Stoechospermum marginatum; and five red-Amphiroa anceps, Grateloupia indica, Halymenia porphyriformis, Scinaia carnosa, Solieria chordalis). All seaweeds were analyzed for the proximate composition, including moisture content, ash content, total sugar content, total proteins, total lipids, crude fiber, carotenoid content, total chlorophyll content, proline, iodine content, nitrogen-free extract, total phenolic content and total flavonoid content. Green seaweeds showed higher nutritional proximate composition, followed by brown and red seaweeds. Among the different seaweeds, Ulva, Caulerpa, Sargassum, Spatoglossum and Amphiroa showed high nutritional proximate composition compared to other seaweeds. High cation scavenging, free radical scavenging and total reducing activities were observed for Acrosiphonia, Caulerpa, Ulva, Sargassum, Spatoglossum and Iyengaria. It was also observed that 15 tropical seaweeds contained negligible amounts of antinutritional compounds, including tannic acid, phytic acid, saponins, alkaloids and terpenoids. Nutritionally, green and brown seaweeds provided higher sources of energy (150-300 calories per 100 g) compared to red seaweeds (80-165 calories per 100 g). Additionally, this study also confirmed that tropical seaweeds improved the oxidative stability of food oils and, therefore, might be recommended as natural antioxidant additives. The overall results confirm that tropical seaweeds are potential sources of nutrition and antioxidants and may be explored as functional food, dietary supplementation or animal feed. Additionally, they may also be explored as food supplements for fortifying food products, as food toppings or for garnishing and seasoning foods. However, a human or animal toxicity analysis is required before any conclusive recommendation for daily food or feed intake can be made.

Impact of COVID-19 lockdown on ambient noise levels in seven metropolitan cities of India

The paper analyzed the impact of lockdown on the ambient noise levels in the seventy sites in the seven major cities of India and ascertained the noise scenario in lockdown period, and on the Janta Curfew day in comparison to the pre-lock down period and year 2019 annual average values. It was observed that the majority of the noise monitoring sites exhibited a decrement in ambient day and night equivalent noise levels on the national Janta Curfew day and Lockdown period as compared with the normal working days attributed to the restricted social, economical, industrial, urbanization activity and reduced human mobility. A mixed pattern was observed at a few sites, wherein the ambient day and night equivalent noise levels during Janta curfew day and Lockdown period had been reported to be higher than that on the normal working days. The study depicts the noise scenario during the lockdown and pre-lockdown period for seventy sites in India and shall be instrumental in analyzing the consequences and implications of imposing lockdowns in future on the environmental noise pollution in Indian cities.

A profile of a retrospective cohort of 22 patients with COVID-19 and active/treated tuberculosis

We read with interest the two articles by Tadoliniet al. [1] and Stochinoet al. [2], which described recent cohorts of either current or former tuberculosis (TB) patients with coronavirus disease 2019 (COVID-19) and studied their clinical course. India has the majority of global burden of TB, along with highest rising number of daily COVID-19 cases in the world [3, 4]. The information about COVID-19 and active/former TB co-infection reported so far is sparse, but it can be assumed that person with TB, when co-infected with COVID-19, may be at more risk of poor outcomes [1, 5]. The present study describes the first-ever cohort of current or treated TB patients co-infected with COVID-19 from a high TB burden country, recruited by a tertiary care hospital in India.

Both tuberculosis and COVID-19 being communicable and prevalent diseases in India, the co-existence can lead to worse outcomes, as seen in this study, where there was high mortality among active as well as treated TB patients with COVID-19 co-infectionhttps://bit.ly/3jHcGbQ

Brucellosis in India: results of a collaborative workshop to define One Health priorities

Brucellosis is an important zoonosis worldwide. In livestock, it frequently causes chronic disease with reproductive failures that contribute to production losses, and in humans, it causes an often-chronic febrile illness that is frequently underdiagnosed in many low- and middle-income countries, including India. India has one of the largest ruminant populations in the world, and brucellosis is endemic in the country in both humans and animals. In November 2017, the International Livestock Research Institute invited experts from government, national research institutes, universities, and different international organizations to a one-day meeting to set priorities towards a "One Health" control strategy for brucellosis in India. Using a risk prioritization exercise followed by discussions, the meeting agreed on the following priorities: collaboration (transboundary and transdisciplinary); collection of more epidemiological evidence in humans, cattle, and in small ruminants (which have been neglected in past research); Economic impact studies, including cost effectiveness of control programmes; livestock vaccination, including national facilities for securing vaccines for the cattle population; management of infected animals (with the ban on bovine slaughter, alternatives such as sanctuaries must be explored); laboratory capacities and diagnostics (quality must be assured and better rapid tests developed); and increased awareness, making farmers, health workers, and the general public more aware of risks of brucellosis and zoonoses in general. Overall, the meeting participants agreed that brucellosis control will be challenging in India, but with collaboration to address the priority areas listed here, it could be possible.

Effect of head posture on tooth contacts in dentate and complete denture wearers using computerized occlusal analysis system

Purpose:

The purpose of the study was to assess and compare the occlusal contacts in dentate and edentulous patients wearing complete denture with varying head posture.

Materials and Methods:

Ad hoc sampling of 30 subjects (15 dentate and 15 edentulous) based on inclusion and exclusion criteria was done. Subjects were divided into two groups: dentate and edentulous. Each group was further divided into two subgroups based on two head postures-upright 90° and ventroflexed 30°. For recording of every posture, a new sensor was used, and the subject was asked to clench on the sensor in maximum intercuspation position at the two head postures.

Results:

Data were summarized as mean ± standard error and compared by Student's t-test using SPSS software (windows version 17.0 IBM corporation, New York, USA). A statistically significant correlation between head posture and contact area was found in dentate and denture wearers, i.e., tooth contact area varies with head posture.

Conclusion:

It was concluded that the occlusal contacts vary at different head posture in dentate as well as in denture wearers. With ventroflexion, the number of tooth contact decreased as compared to upright-erect position in both groups. Clinical implication - since the number of tooth contacts varies with varying head postures, it is recommended that the balancing of the contacts should be done at varying head postures.

Transient hypercoagulability in adult patients following open-heart surgery

The technique of thrombelastography was used to assess whether the phenomenon of hypercoagulability (accelerated coagulation) occurred in adult patients (n = 20) undergoing consecutive open-heart surgical procedures. Standard haematological investigations (pre- and 2 hours postop) were also performed and comparisons made with thrombelastographic parameters. Thrombelastographic hypercoagulability was identified in 12/20 (60%) cases but this event was transient occurring immediately postprotamine administration, and normalizing at 2h postoperation. The standard postoperative haematological assessments routinely made 2h after operation failed to detect this phenomenon. Hypercoagulability following cardiac surgery in adult patients merits further evaluation in order that the clinical significance may be determined.

Delayed hematopoietic recovery after auto-SCT in patients receiving arsenic trioxide-based therapy for acute promyelocytic leukemia: a multi-center analysis

A potential link between arsenic (ATO)-based therapy and delayed hematopoietic recovery after autologous hematopoietic SCT (HSCT) for acute promyelocytic leukemia (APL) has previously been reported. We retrospectively reviewed the clinical histories of 58 patients undergoing autologous HSCT for APL at 21 institutions in the United States and Japan. Thirty-three (56%) of the patients received ATO-based therapy prior to stem cell collection. Delayed neutrophil engraftment occurred in 10 patients (17%): 9 of the 10 patients (90%) received prior ATO (representing 27% of all ATO-treated patients), compared with 1 of the 10 patients (10%) not previously treated with ATO (representing 4% of all ATO-naïve patients; P<0.001). Compared with ATO-naïve patients, ATO-treated patients experienced significantly longer times to ANC recovery (median 12 days vs 9 days, P<0.001). In multivariate analysis, the only significant independent predictor of delayed neutrophil engraftment was prior treatment with ATO (hazard ratio 4.87; P<0.001). Of the available stem cell aliquots from APL patients, the median viable post-thaw CD34+ cell recovery was significantly lower than that of cryopreserved autologous stem cell products from patients with non-APL AML. Our findings suggest that ATO exposure prior to CD34+ cell harvest has deleterious effects on hematopoietic recovery after autologous HSCT.

Comparative evaluation of vertical dimension at rest before extraction, after extraction and after rehabilitation with complete denture - A Cephalometric study

INTRODUCTION

The determination of physiologic rest position of the mandible to the maxillae is of paramount importance in almost all fields of dentistry. The stability of vertical dimension at rest has been controversial if the rest position of mandible remains constant throughout life or not. Despite of several studies on the rest position of the mandible and facial vertical dimension, certain fundamental disagreements remain unresolved. The present study aims to compare the vertical dimension at rest, before and after extraction and after rehabilitation with complete denture.

MATERIAL & METHODS

This study was conducted in a total of ten randomly selected patients, who had some natural teeth present with one or more opposing posterior teeth with vertical occlusal stops but were advised for extraction because of poor prognosis. Digital lateral cephalograms were done and measurements recorded at three stages: prior to extraction of remaining natural teeth, post extraction and after complete denture rehabilitation.

RESULTS

Vertical dimension at rest was found to be greatest in post rehabilitation followed by pre-extraction than post extraction state. The differences in changes were found to be statistically significant.

CONCLUSION

Vertical dimension at rest shows a decrease following extraction of natural teeth, the occlusal stops, and an increase on rehabilitation. It can be stated that vertical dimension at rest is not stable position and varies following extraction of natural teeth and rehabilitation.

Echocardiographic evaluation of heart in chronic obstructive pulmonary disease patient and its co-relation with the severity of disease

Background:

Chronic obstructive pulmonary disease (COPD) has considerable effects on cardiac functions, including those of the right ventricle, left ventricle, and pulmonary blood vessels. Most of the increased mortality associated with COPD is due to cardiac involvement. Echocardiography provides a rapid, noninvasive, portable, and accurate method to evaluate the cardiac changes.

Aims:

To assess the cardiac changes secondary to COPD by echocardiography and to find out the correlation between echocardiographic findings and severity of COPD, if there is any.

Materials and Methods:

A total 40 of patients of COPD were selected and staged by pulmonary function test (PFT) and evaluated byechocardiography.

Results:

On echocardiographic evaluation of COPD, 50% cases had normal echocardiographic parameters. Measurable tricuspid regurgitation (TR) was observed in 27/40 cases (67.5%). Pulmonary hypertension (PH), which is defined as systolic pulmonary arterial pressure (sPAP)> 30 mmHg was observed in 17/27 (63%) cases in which prevalence of mild, moderate, and severe PH were 10/17 (58.82%), 4/17 (23.53%), and 3/17 (17.65%), respectively. The frequencies of PH in mild, moderate, severe, and very severe COPD were 16.67%, 54.55%, 60.00%, and 83.33%, respectively. Right atrial pressure was 10 mmHg in 82.5% cases and 15 mmHg in 17.5% cases. Cor pulmonale was observed in 7/17 (41.17%) cases; 7.50% cases had left ventricle (LV) systolic dysfunction and 47.5% cases had evidence of LV diastolic dysfunction defined as A ≥ E (peak mitral flow velocity of the early rapid filling wave (E), peak velocity of the late filling wave caused by atrial contraction (A) on mitral valve tracing) Left ventricle hypertrophy was found in 22.5% cases.

Conclusion:

Prevalence of PH has a linear relationship with severity of COPD and severe PH is almost associated with cor pulmonale. Echocardiography helps in early detection of cardiac complications in COPD cases giving time for early interventions.

Review article: The use of potentially hepatotoxic drugs in patients with liver disease

BACKGROUND

Misconceptions surround the use of hepatotoxic drugs in chronic liver disease. While many prescription and over-the-counter (OTC) agents can be used safely, this often runs counter to labelled warnings/contraindications, especially for the statins and other commonly used agents.

AIM

To evaluate published data on the use of hepatotoxic drugs in chronic liver disease including pharmacokinetic changes in cirrhosis and drug interactions, where available, to formulate recommendations on their use.

METHODS

Using a combination of PubMed searches, review texts, the Physicians' Desk Reference and expert opinion, drugs considered at higher risk of hepatotoxicity in chronic liver disease were evaluated.

RESULTS

Most drugs and OTC products including herbals have not been formally studied in chronic liver disease, but available data suggest that several of the most commonly used agents, especially the statins, can be used safely. While there is an increased risk of drug-induced liver injury for drugs used in the treatment of tuberculosis and HIV patients with hepatitis B or C, recommendations for their safe use are emerging.

CONCLUSIONS

Although many clinicians remain hesitant to use hepatotoxic drugs in chronic liver disease, the database supporting this view is limited to just a few agents. Most medications can be used safely in patients with chronic liver disease with appropriate monitoring.

Risk of lymphoid follicle development in patients with chronic antral gastritis: role of endoscopic features, histopathological parameters, CagA status and interleukin-1 gene polymorphisms

OBJECTIVE

Helicobacter pylori infection causes gastritis, lymphoid follicle formation and development of MALT lymphoma. We evaluated endoscopic, histological, serological and genetic risk factors associated with lymphoid follicle development in gastritis.

MATERIALS AND METHODS

After upper GI endoscopy, 3 antral biopsies were taken from 120 patients for histological examination. H. pylori was diagnosed using rapid urease test (RUT), modified Giemsa stain and IgG anti-CagA ELISA. Genotyping of IL-1B (-511C/T) and IL-1RN (86 bp VNTR) genes were performed by PCR-RFLP/PCR.

RESULTS

In 120 patients, 45 (37.5%) showed presence of lymphoid follicles in antral gastric mucosa. H. pylori was positive by modified Giemsa stain (26%) RUT (50%) and anti-CagA IgG in 67.5%, The presence of nodularity (p = 0.030), neutrophilic infiltration (p = 0.010), lymphocytic infiltration (p = 0.002), glandular atrophy (p = 0.0001), glandular shortening (p = 0.001), fibrosis (p = 0.0001), plasma cells (p = 0.007), eosinophils (p = 0.012), anti-CagA antibodies (p = 0.003) and H. pylori density (p = 0.020) were associated with risk (odds ratio = 11.5, 3.8, 11.0, 8.4, 3.8, 4.6, 5.8, 16.0, 10.8 and 2.8 respectively) of lymphoid follicle. However, IL-1 gene polymorphisms did not influence lymphoid follicle development

CONCLUSION

The presence of modularity, lymphocytic infiltration, glandular atrophy, glandular shortening, fibrosis, plasma cells, eosinophils and anti-CagA IgG antibodies are risk factors for lymphoid follicle development in patients with gastritis.

Cytokine gene polymorphisms and the pathology of chronic gastritis

INTRODUCTION

Helicobacter pylori (H. pylori) infection is associated with divergent clinical outcomes and these outcomes are largely influenced by the levels of cytokines in the gastric mucosa. The levels of these cytokines are dependant on cytokine gene polymorphisms. Pro-inflammatory cytokine polymorphisms are strongly associated with severe histological changes in the gastric mucosa in Caucasian populations.

METHODS

In this study, we evaluated the role of cytokine gene polymorphisms in influencing the pathological severity of gastritis. 120 patients were evaluated. Cytokine gene polymorphisms of interleukin-1 (IL-1) beta, tumour necrosis factor alpha and the IL-1 receptor antagonist genes were done using polymerase chain reaction (PCR) restriction fragment length polymorphism and PCR variable number of tandem repeats markers typed on the deoxyribonucleic acid obtained from the peripheral blood. Histological analysis was done by using the revised Sydney system.

RESULTS

There was no association between pro-inflammatory cytokine gene polymorphisms and severity of gastritis.

CONCLUSION

This data suggests that high cytokine levels are not seen in the gastric mucosa in Indians in spite of H. pylori colonisation. IL-1 beta is a potent proinflammatory cytokine which causes a partial clearance of the organism as well as hypochlorhydria. Corporal hypochlorhydria causes a persistent colonisation by H. pylori followed by the development of gastric atrophy and later carcinoma. This lack of association with a pro-inflammatory polymorphism suggests that only low levels of IL-1 beta are present in the gastric mucosa. This causes a low clearance of the organism and a high incidence of duodenal ulceration because of hyperchlorhydria. However, it is protective against the development of gastric carcinoma. This would explain the "Indian Paradox" of the apparent discrepancy of a high degree of colonisation by H. pylori and a low incidence of gastric carcinoma in the Indian population.

The role of mast cells and eosinophils in chronic gastritis

The role of mast cells and eosinophils in influencing the pathology of chronic gastritis remains unclear. We attempted to study the relationship between endoscopy and the mast cell and eosinophil infiltrate. We also studied the role of gene polymorphisms, Helicobacter pylori density and the CagA antibody status in influencing the mast cell and eosinophil infiltrate. One hundred and twenty consecutive patients were studied. Endoscopic evaluation was done and 3 antral biopsies were taken from each patient and were assessed for eosinophilic and mast cell infiltration, H. pylori density and the density of the other inflammatory cells as per the revised Sydney system. Cytokine gene polymorphisms (IL-1beta, IL-1RA and TNF-alpha) were done on the DNA extracted from the peripheral blood by PCR-RFLP. ELISA was done on the patients' serum for the anti-CagA antibody titres. Nodularity is strongly associated with the presence and density of eosinophils on biopsy (P < 0.05). Eosinophil density is strongly associated with the density of H. pylori, neutrophils, lymphocytes, plasma cells, atrophy, ulceration, foveolitis and lymphoid follicles. The mast cell density is not associated with any of the other histopathological variables. Gene polymorphisms and the CagA antibody titres have no relationship to the mast cell and eosinophil density. Eighty-one patients showed positive anti-CagA antibody titres but there was no association with the eosinophilic or the mast cell infiltrate. It is likely that eosinophilic infiltration is influenced by the H. pylori density but the CagA protein has no role to play in influencing the grade of the eosinophilic infiltrate in the Indian context. Cytokine gene proinflammatory polymorphisms have no role to play in influencing the eosinophilic or the mast cell response. It is likely that other mediators are involved in the inflammatory cell responses.

The histopathology of chronic gastritis

Chronic gastritis is a multifactorial disorder thought to be influenced by bacterial and host genetic factors. Histopathological examination is the mainstay of diagnosis, however features like the presence of Helicobacter pylori are difficult to evaluate on biopsy. We evaluated 120 gastric antral biopsies using the revised Sydney system. The density of the inflammatory infiltrate, H pylori and mast cells were evaluated. It was seen that the presence of H pylori is strongly associated with an acute and a chronic inflammatory infiltrate. The presence of neutrophils on biopsy is strongly associated with the presence of H pylori and with the density and the grade of the chronic inflammatory infiltrate. The chronic inflammatory response is an intermediary between the acute inflammatory process and glandular atrophy. The lymphocytic infiltrate is also a precursor lesion of the lymphoid follicles. The presence of mast cells does not appear to be related to any of the other inflammatory parameters. The presence of one feature is a strong indicator for the presence of other inflammatory features.

Outbreak of Scrub Typhus in Jammu - A Report

BACKGROUND

Jammu is scrub typhus prone. Scrub typhus is often seen when troops move out of permanent locations.

METHODS

In a prospective study cases of fever reporting to the local military hospital from July to October 2002 were examined clinically, investigated and categorised as scrub typhus when Weil Felix readings were above 1:160.

RESULTS

Twelve cases of scrub typhus were diagnosed during the period of study. The clinical features included fever, malaise and conjunctival congestion. However rashes were rare and only one had an eschar. Multisystem complications occurred in one patient. There was a spatial and temporal clustering of cases. Control of outbreak was carried out by 25% benzyl benzoate impregnation of clothing, clearing of scrub, residual spray with malathion and antirodent measures.

CONCLUSION

Scrub typhus outbreaks have been noted whenever troops move out of permanent locations to scrub areas.

Concomitant methotrexate and radiotherapy in advanced head and neck cancer: 15-year follow-up of a randomized clinical trial

Long-term follow-up for patients who receive chemoradiation for head and neck cancer is lacking from most studies reported in the literature. This report gives a 15-year review of the use of concomitant methotrexate and radiation in advanced head and neck cancer. Although there has not been any significant benefit in overall survival, the primary control rate is higher in patients who received methotrexate in addition to radiotherapy. However, in those with oropharyngeal cancer, both primary control and survival were significantly improved when chemotherapy was used. The other most significant benefit from chemoradiation is the much lower rate of salvage operations for primary recurrence. The addition of methotrexate failed to show any effect on the development of metastatic neck nodes. The rate of block dissection of the neck was similar in both arms of the study and is comparable with the historical data collected at this institute. There has not been any significant increase in serious late morbidity. The timing of the methotrexate with radiotherapy has a significant influence on primary control and survival in head and neck cancer.

Bilateral ectopia lentis as a presenting feature of medulloepithelioma

Ectopia lentis may be a feature of numerous systemic and ocular disorders. Kivela and Tarkkanen described an 8-year-old girl with medulloepithelioma who presented with ectopia lentis and a mass behind the temporal iris. Shields reported 2 children with medulloepithelioma who had ectopia lentis associated with neovascular glaucoma. To date, there has been no report of a child with ectopia lentis as the only presentation of an intraocular tumor. We present 2 children with malignant medulloepitheliomas who presented in this fashion.

331 cases of clinically node-negative supraglottic carcinoma of the larynx: a study of a modest size fixed field radiotherapy approach

PURPOSE

For node-negative supraglottic carcinoma of the larynx, radiotherapy with surgery in reserve commonly provides very good results in terms of both local control and survival, while preserving function. However uncertainty exists over the treatment of the node-negative neck. Elective whole neck radiotherapy, while effective, may be associated with significant morbidity. The purpose of this study was to examine our practice of treating a modest size, fixed field to a high biologically effective dose and compare it with the patterns of recurrence from other centers that use different dose/volume approaches.

METHODS AND MATERIALS

Over a 10-year period 331 patients with node-negative supraglottic carcinoma of the larynx were treated with radiotherapy at the Christie Hospital Manchester. Patients were treated with doses of 50-55 Gy in 16 fractions over 3 weeks. Data were collected retrospectively for local and regional control, survival, and morbidity.

RESULTS

Overall local control, after surgical salvage in 17 cases, was 79% (T1-92%, T2-81%, T3-67%, T4-73%). Overall regional lymph node control, after surgical salvage in 13 cases, was 84% (T1-91%, T2-88%, T3-81%, T4-72%). Five-year crude survival was 50%, but after correcting for intercurrent deaths was 70% (T1-83%, T2-78%, T3-53%, T4-61%). Serious morbidity requiring surgery was seen in 7 cases (2.1%) and was related to prescribed dose (50 Gy-0%, 52.5 Gy-1. 3%, 55 Gy-3.4%).

DISCUSSION

Our results confirm that treating a modest size, fixed field to a high biologically effective dose is highly effective. It enables preservation of the larynx in most cases, with acceptable regional control and no loss of survival compared to whole neck radiotherapy regimes.

Evaluating contraceptive choice through the method-mix approach. An Indian Council of Medical Research (ICMR) task force study

The method-mix approach was used to evaluate informed contraceptive choices in the present study. A total of 8,077 potential clients were given a balanced presentation of all available contraceptive methods in the national program, ie, the CuT 200 intrauterine device (IUD), low-dose combined oral pills (OC), condom, and sterilization (female/male) along with a new method, Norplant(R).(1) The majority of women opted for spacing methods; among them, the IUD was preferred by about 60% of clients, followed by condoms (9%), OC (6%), and Norplant (5%). Sterilization, mainly female, was accepted by about 17% of the women making an informed choice. The economic status of couples did not influence the contraceptive choices, as all the methods were offered free of cost in the present study, which is the current practice in the national program. Illiterate women more often accepted sterilization (about 25%) than did literate women (15%). This is because illiterate women had more children; about 30% of illiterate women had three or more children, as opposed to 16.2% of literate women. However, literacy status did not influence the choice of any specific spacing method. The study also revealed that, by encouraging potential clients to make an informed choice, they could override the provider's bias while accepting a particular type of spacing method. This is evident from the observation that Norplant was the first choice of the provider for 35% of the women, whereas only 5% of women preferred and accepted Norplant. The present study stresses an urgent need to promote the practice of informed choices in the national program with a variety of contraceptive options-especially, spacing methods for improving contraceptive prevalence and reproductive health in the country.

Self-expanding oesophageal metal stents for the palliation of dysphagia due to extrinsic compression

The role of self-expanding metallic stents is well established in the palliation of oesophageal stenosis and dysphagia due to primary oesophageal malignancy. However, their role in palliation of dysphagia due to external compressive mediastinal malignancies is not well established. The purpose of this study was to assess the efficacy of self-expanding metallic stents in the palliation of dysphagia due to extrinsic oesophageal compression by mediastinal malignancy. Between January 1995 and January 1998, 21 patients with oesophageal compression due to malignant mediastinal tumours underwent oesophageal stent placement for palliation of dysphagia. Complete data were available in 17 patients (10 men and 7 women). The mean age was 63.5 years (range 46-89 years). A total of 19 stents were placed successfully. The dysphagia grade prior to and after oesophageal stent placement was assessed and the complications documented. Of the 17 patients, 16 reported an improvement in dysphagia. The mean dysphagia score improved from 3.1 prior to treatment to 1.3 after treatment. In 1 patient the stent slipped during placement and another stent was placed satisfactorily. Early complications (within 48 h) in the form of mild to moderate retrosternal chest pain occurred in 5 patients. This was treated symptomatically. Late complications (after 48 h) in the form of bolus impaction occurred in 2 patients. This was successfully treated with oesophagoscopy and removal of bolus. In 2 patients the stent was overgrown by tumour and in one of these an additional stent was placed. In 1 patient incomplete closure of a tracheo-oesophageal fistula was observed. There was no procedure- or stent-related mortality. The mean survival time of this group was 2. 1 months. Self-expanding metallic stents can be safely and effectively used in the palliation of dysphagia due to external mediastinal malignancies.

Differential effects of neurotoxic destruction of descending noradrenergic pathways on acute and persistent nociceptive processing

Although many pharmacological studies indicate that bulbospinal noradrenergic projections contribute to antinociception, lesions of the major brainstem noradrenergic cell groups have provided conflicting evidence. Here we used a new immunotoxin, anti-dopamine beta-hydroxylase-saporin, to re-examine the contribution of noradrenergic pathways to nociception and to morphine analgesia. We treated rats intrathecally by lumbar puncture with the immunotoxin and examined dopamine beta-hydroxylase (DbetaH) immunoreactivity seven and 14 days after treatment. There was no change in DbetaH staining at 7 days; however, 14 days after treatment we demonstrated significant destruction of noradrenergic neurons in the locus coeruleus and in the A5 and A7 cell groups. There was a concomitant loss of noradrenergic axons in the dorsal and ventral horns of the lumbosacral and cervical cord. Consistent with the lack of anatomical changes, we found no difference in nociceptive responses in the hot-plate, tail-flick or formalin tests one week post-toxin. On day 14 we examined the behavioral response to injection of formalin into the hindpaw and found that responses during the second phase of pain behavior were significantly reduced. There was no change during the first phase. Formalin-evoked fos expression in the spinal cord was also reduced. We also evaluated morphine analgesia in the formalin test and found that toxin-treated animals exhibited enhanced morphine analgesia. These results establish the utility of using this immunotoxin to selectively destroy subpopulations of noradrenergic cell groups and provide evidence that acute and persistent nociception are differentially regulated by descending noradrenergic pathways.

Submandibular gland carcinoma; an audit of local control and survival following adjuvant radiotherapy

Carcinoma of the submandibular gland is a rare diagnosis, accounting for less than 2% of cases of salivary gland tumours. We have examined the treatment and outcome of a total of 30 patients treated with radiotherapy at the Christie Hospital, Manchester between 1980 and 1993. In most cases this followed radical surgery, though 12 patients were referred following either incomplete excision or biopsy only. Adenoid-cystic histology accounted for 19 cases (63%). Standard radiotherapy was delivered using a beam directed technique to treat the whole submandibular compartment. Doses prescribed were most commonly from 50 to 55 Gy in 16 fractions over three weeks. Cancer specific survival was 79% and 57% at 5 and 10 yr respectively, the continued fall at 10 yr reflected late recurrence seen in patients with adenoid-cystic histology. Local control was 85% and 73%, respectively. Nine of twelve patients with incomplete excision or biopsy only had local control with radiotherapy. Six patients developed lung metastases, all of whom had adenoid-cystic histology. Radiotherapy was well-tolerated acutely, and only one patient experienced osteoradionecrosis requiring surgical intervention. The incidence of adenoid-cystic carcinoma is higher in the submandibular than the parotid gland. This typically results in late recurrence, and a high incidence of lung metastases and this was confirmed in our study. However, overall survival was very similar to that of parotid carcinoma.

Does salivary gland scintigraphy predict response to pilocarpine in patients with post-radiotherapy xerostomia?

This study was undertaken to determine whether standard salivary gland scintigraphy may be used for the objective assessment of salivary gland sialogogues, in particular oral pilocarpine, in the treatment of post-radiotherapy xerostomia. Nine patients, with xerostomia following radiotherapy to the head and neck region underwent salivary gland scintigraphy with technetium-99m pertechnetate (40 MBq) both before and following 1 month of oral pilocarpine (5 mg tds). For each scan, the percentage uptake in the first 14 min, the peak uptake, time to peak uptake and the percentage of activity excreted following lemon juice stimulation were calculated. The results were correlated with the subjective response as assessed by questionnaire and visual analogue scale. We found no correlation between subjective response and any of the four scan parameters analysed. We could not identify any parameter that predicted those patients who would respond to pilocarpine. In addition, only one parameter, the percentage of activity excreted following stimulation, correlated with previous dose of radiotherapy to the gland. In conclusion, in this study salivary gland scintigraphy did not appear to correlate with or predict response to oral pilocarpine. However, future studies might consider performing salivary gland scintigraphy prior to radiotherapy as well as at differing time points following the commencement of pilocarpine.

Expression and activity of p67 are induced during heat shock

p67, a cellular glycoprotein, protects eIF2 alpha from phosphorylation by inhibitory kinases such as PKR and HCR. p67 promoter contains heat shock element (HSE). To investigate whether this HSE of p67 has any role during heat-shock, rat tumor hepatoma cells were transiently transfected with CAT reporters linked to p67 promoter with HSE and without HSE. Heat shock induced CAT activity when p67 promoter contained HSE and this induction was not observed when HSE was deleted from the p67 promoter. In response to heat-shock, the endogenous p67 mRNA was also induced to more than 36-fold, and much of it translated into protein which was modified by GlcNAc moieties. The time of induced glycosyl modification at the later stages of the heat-shock correlates with the reduced level of eIF2 alpha phosphorylation. During later stages of the heat shock of animal cells, there is a preferential translation of a small class of messages encoding heat shock proteins. Our results suggest that the expression and activity of p67 are induced at the later stages of the heat-shock, and may be involved in the preferential translation of the heat-shock messages.

Viral infection. II. Hemin induces overexpression of p67 as it partially prevents appearance of an active p67-deglycosylase in baculovirus-infected insect cells

The roles of p67-deglycosylase (p67-DG) in the regulation of protein synthesis in baculovirus-infected insect cells were studied. Like vaccinia viral infection, baculovirus infection of insect cells also induced the appearance of a p67-DG. However, p67-DG activity could not be detected because these cells do not contain a detectable level of p67. The baculovirus expression vector system (BEVS), however, promotes significant expression of cloned p67-cDNA. The expression of p67 was significantly enhanced by the addition of hemin to the growth medium. Maximum enhancement was observed at 5 microM hemin. Data suggest that hemin prevents the activation of latent p67-DG inside the cell and does not have any effect on p67 gene transcription. To gain a better understanding of the mechanism of p67-DG activation and hemin stimulation of p67 synthesis, we have now purified p67-DG from baculovirus-infected insect cells. We prepared antibodies against this protein. These antibodies reacted with a 105-kDa protein in cell extracts from the uninfected insect cells (Sf9), KRC-7, and L929 (animal cells). In addition, these antibodies reacted with an additional 60-kDa protein in the cell extracts of baculovirus-infected Sf9 cells and vaccinia virus-infected KRC-7 and L929 cells. Data are also presented to show that the antibodies against p67-DG reacted more efficiently (40%) with the 60-kDa protein in both hemin-deficient reticulocyte lysate and hemin-deficient baculovirus-infected cells. We suggest that hemin prevents the conversion of an inactive p67-DG into an active form possibly by covalent modification such as protein phosphorylation or protein glycosylation. The active form is more efficiently recognized by the p67-DG antibodies since these antibodies were prepared against the active form of p67-DG.

Viral infection. I. Regulation of protein synthesis during vaccinia viral infection of animal cells

Regulation of vaccinia viral infection was studied using three animal cell lines: KRC-7 (rat hepatoma), L929 (mouse fibroblast), and CV-1 (African green monkey kidney). KRC-7 is highly enriched in p67, a glycoprotein which protects eIF-2 alpha-subunit from phosphorylation by eIF-2 kinases. We report: (i) At 5 pfu per cell of the virus, KRC-7 is resistant to the virus. Other cells are sensitive. At 25 pfu per cell of the virus, KRC-7 is also sensitive to the virus. After productive viral infection, the cell extracts showed strong p67-DG activity and actively deglycosylated exogenous p67. After p67-deglycosylation, the cell extracts also phosphorylated eIF-2. (ii) The rate of synthesis of a major host protein (approximately 45 kDa) in infected L929 cells measured after 2 h of viral infection declined more than 50%. The rate declined thereafter. The rate of synthesis of host proteins in viral-resistant KRC-7 cells (infected with 5 pfu per cell of the virus) remained unchanged. The mechanism of resistance of KRC7 cells to vacinia virus at 5 pfu per cell of the virus was investigated. The p67 level in these cells was varied by growing the cells under different physiological conditions such as serum starvation and expression of p67-sense and p67-antisense DNA. At low p67 level in the cells, p67-DG is activated. This deglycosylates p67 and inactivates p67. This accompanies eIF-2 phosphorylation and shutoff of host protein synthesis. At high p67 level in the cells, activation of p67-DG is prevented. This prevents shut-off of host protein synthesis and viral growth.

Cloning and characterization of the promoter region of a gene encoding a 67-kDa glycoprotein

A rat genomic library constructed in lambda-EMBL3 (SP6/T7) vector () was screened using 32P-labeled rat p67 cDNA. A clone containing a segment of 5'-upstream region of p67 genomic DNA was obtained. The DNA (about 1.7 kilobase pairs) was isolated and characterized. Sequence analysis of this DNA fragment showed that the 898 base pairs at the 5'-end of the upstream region was identical to several long interspersed nucleotide sequences. One hundred forty-eight base pairs at the 3'-end contained the beginning of the first exon including the ATG initiator codon. The remaining 652 base pairs in between contained two AT-rich regions and several regulatory sequences. The mRNA initiation site was identified at 89 base pairs upstream from the translation start codon. The DNA fragment was also analyzed by transient transfection. When linked to a firefly luciferase reporter gene, this fragment enhanced transcription in a rat hepatoma cell line (KRC-7). Using a series of deletions in the DNA, the minimum essential promoter region (from -177 to -60) was identified. The promoter activity was also enhanced by treatment with phorbol 13-myristate 12-acetate (PMA). This enhancement required an AP-1 sequence (-298 to -292; 5'-TGACTCA-3') and a similar sequence (-97 to -88; 5'-ATGACATCAT-3'). Deletion of either of these sequences significantly reduced PMA enhancement. Deletion of both of these sequences almost completely eliminated PMA enhancement.

p67 transcription regulates translation in serum-starved and mitogen-activated KRC-7 cells

The regulation of protein synthesis was studied in KRC-7 cells (rat hepatoma) grown in complete medium, during serum starvation, and mitogen activation. Upon serum starvation, the cells lost almost completely p67 mRNA, p67 protein, and protein synthesis activity. After phorbol 12-myristate 13-acetate addition, the same serum-starved cells regained p67 mRNA, p67 protein, and protein synthesis activity. Also, the extracts from the serum-starved cells phosphorylated the eukaryotic initiation factor-2 (eIF-2) alpha-subunit. This eIF-2 alpha-subunit phosphorylation was not observed when the extracts from either the cells grown in complete medium or mitogen-activated cells were used (Gupta, S., Wu, S., Chatterjee, N., Ilan, J., Ilan, J., Osterman, J. C., and Gupta, N. K. (1995) Gene Expr. 5, 113-122). We now report the following. 1) The eIF-2 kinase activity was the same in the cells grown in complete medium, after serum starvation, and subsequent mitogen stimulation. However, the eIF-2 kinase in the cells grown in complete medium and also after mitogen activation of the serum-starved cells cannot phosphorylate eIF-2 alpha-subunit as these cells contain p67. After removal of endogenous p67 by p67 antibodies, the extracts from all these cells similarly phosphorylated exogenously added eIF-2. 2) None of the cell extracts showed p67 deglycosylase activity. 3) The p67 mRNA was synthesized in serum-starved cells by expression of a p67 cDNA. The appearance of p67 mRNA in the serum-starved cells was accompanied by the appearance of p67 protein. Also, the rates of protein synthesis in the serum-starved cells were restored nearly to the level observed in the confluent cells. The expression of p67 cDNA also significantly increased protein synthesis rates in the cells grown in complete medium and in mitogen-activated cells. These results show that the loss of protein synthesis activity in serum-starved cells was due to loss of p67 mRNA. The expressed p67 mRNA was stable in serum-starved cells. These results, therefore, suggest that the loss of p67 mRNA in serum-starved cells is due to loss of p67 transcription. The p67 transcription regulates translation.

Intracavitary radiotherapy boosting for nasopharynx cancer

Intracavitary radiotherapy is conceptually an attractive method of boosting dose to nasopharynx cancer whilst sparing sensitive normal tissues. A high dose rate (HDR) microselectron can be used to deliver a brachytherapy boost conveniently, safely, comfortably and effectively. Following external radiotherapy a single outpatient treatment has been given to patients using the remote afterloading system of sources placed in modified paediatric endotracheal tubes. This has been associated with good primary control and no evidence of serious morbidity in eight patients. The main limitation of this method is restriction of its utilization to small volume primary disease.

Olfactory neural tumours--the role of external beam radiotherapy

Olfactory neuroblastoma is an uncommon tumour arising in the nasal cavity or paranasal sinuses. We report the management of nine cases treated with external beam radiotherapy subsequent to surgery, either attempted definitive removal or biopsy only. Recent refinements in pathological evaluation of these tumours are discussed. Seven cases were deemed classical olfactory neuroblastoma whilst two were classified as neuroendocrine carcinoma. The clinical features, radiotherapy technique and variable natural history are presented. Seven of eight patients treated radically were controlled locally, with a minimum follow-up of two years. Three patients developed cervical lymph node disease and three patients died of systemic metastatic disease. Suggestions are made as to which patients should have en-bloc resection rather than definitive radiotherapy.

Radical external beam radiotherapy for 333 squamous carcinomas of the oral cavity--evaluation of late morbidity and a watch policy for the clinically negative neck

BACKGROUND AND PURPOSE

The aims of this study were to examine local control/morbidity for all cases and a 'watch policy' for the node-negative neck.

PATIENTS/METHODS

333 patients with squamous cell carcinoma of the oral cavity were treated with a short radical radiotherapy regime to the primary site and involved lymph node groups at the Christie Hospital, Manchester, between 1980 and 1987. Only 10 of 278 node-negative patients received elective neck node irradiation.

RESULTS

Actuarial cancer-free survival and local control rates at 5 years for the whole group were 55% and 61%, respectively. Control at the primary site was adversely related to increasing T-stage, node positivity and bone involvement at presentation. Osteonecrosis was seen in 14 (5.9%) of 237 cases without bone involvement at presentation. Taking all patients, late morbidity (non-healing soft tissue injury or bone necrosis) was seen in 45 patients (13.6%) at a median time of 21 months from treatment. The factors contributing to late morbidity were: (1) bone involvement at presentation, (2) synchronous MTX chemotherapy, (3) the contribution of scattered radiation from elective neck treatment, (4) increasing radiation dose, (5) increasing target volume for doses less than 55 Gy and (6) dental extractions. Eighty-four (31%) patients who were initially node-negative developed disease in the untreated neck during follow-up. Salvage neck dissections controlled neck disease in half of the node-only recurrences (21/42 cases).

CONCLUSION

These results have influenced our treatment policy, with lowering of the primary tumour dose in some cases and addition of elective neck irradiation for T2-T4 No patients.

Primary lymphoma of the skull presenting as multiple cranial nerve palsies

Lymphoma presenting with isolated diffuse infiltration of the skull is exceedingly rare, with less than 20 previously reported cases. The clinical presentation of a 73-year-old female with primary lymphoma of the skull, manifesting multiple cranial nerve palsies and infiltration of the temporalis muscles is described. MRI of the head, revealed an abnormal signal from the diploic space of the call varium and skull base on both T1 and T2 weighted images, infiltration of the temporalis muscles and clivus, and diffuse meningeal enhancement encroaching on the cavernous sinus bilaterally. Biopsy of temporalis muscle and skull showed a diffuse large cell lymphoma, B-cell type. Staging workup failed to reveal any other sites of disease. Despite multiple cranial nerve palsies, there was no evidence of leptomeningeal disease on CSF examination. MRI was instrumental in demonstrating the abnormalities that lead to the diagnostic biopsy.

Modification of radiation induced changes in murine hepatic lipid profiles by garlic (Allium sativum Linn.) unsaturated oils

Adult male Swiss albino mice were administered 74 kBq g-1 body weight of 45Ca in the presence and absence of garlic unsaturated oils, and the changes in total lipids, triglycerides, phospholipids and free fatty acids contents of liver were observed at various intervals from 1 to 14 days post-treatment. The results obtained indicate that garlic oils prevented rapid increase in hepatic total lipids, triglycerides and phospholipids and decrease in free fatty acids induced by radiocalcium and the values reached normal values earlier in garlic treated animals than in irradiated animals. Possible mechanism underlying the protective action of garlic oils is reported.

Myocardial perfusion scintigraphy in patients undergoing major non-vascular abdominal surgery

The prognostic value of myocardial perfusion scintigraphy is beginning to be recognised in patients undergoing cardiovascular surgery. The aim of this prospective study was to assess the predictive value of scintigraphy in elderly patients undergoing major non-vascular abdominal surgery. Adenosine stress thallium-201 (201Tl) single-photon emission tomography (SPET) was employed for imaging using a standard protocol. Patients over the age of 60 years (n = 55) with an intermediate to high likelihood of coronary artery disease were evaluated prospectively. The clinical outcome variables analysed were cardiac mortality and major cardiac morbidity occurring within 30 days of surgery. Cardiac events were cardiac death (n = 5), angina pectoris (n = 5), nonfatal mycardial infarction (n = 1), acute left ventricular failure (n = 2) and arrhythmias requiring treatment (n = 4). All cardiac events occurred in the first 10 postoperative days except one cardiac death which happened on the 29th postoperative day. Patients with an abnormal 201Tl SPET scan had a higher risk of postoperative death (4 vs 1) or any postoperative cardiac event (13 patients vs 4 patients; P < 0.0001) when compared with those with a normal scan. The sensitivity, specificity and positive predictive value of 201Tl imaging for perioperative ischaemia and adverse outcomes were 76%, 82% and 65%, respectively. The occurrence of an intraoperative event (P < 0.02) and the length of surgery (P < 0.01) were also predictors of a postoperative cardiac event. Clinical risk variables and an abnormal electrocardiogram in isolation were poor predictors. In conclusion, preoperative myocardial perfusion scintigraphy is a valuable technique for identifying elderly patients with a high risk for cardiac events when undergoing major non-vascular abdominal surgery.

Slow bolus injection of ribose in the identification of thallium-201 redistribution following combined adenosine/dynamic exercise stress

AIM

A simple stress/redistribution thallium-201 myocardial perfusion imaging protocol may underestimate the degree of thallium redistribution in a defect identified on the stress images. We sought to investigate whether a slow-bolus injection of D-ribose improves the identification of thallium redistribution following combined adenosine/dynamic exercise stress.

MATERIALS AND METHODS

Fifteen patients (10 males, five female, median age 63 years, range 50-75) were enrolled in the study. All underwent two successive adenosine plus exercise myocardial perfusion scintigraphy protocols 7-14 days apart. Adenosine was infused at 140 micrograms.kg-1.min-1 coupled with 25 W ergometer pedalling for 6 min with 74 Mbq of thallium-201 being injected at 4 min. Immediately following the stress image acquisition, patients received the one of either 60 mg.kg-1 of D-ribose or normal saline, injected over 5 min. Redistribution images were acquired after 4 h. The identical stress procedure was conducted in the crossover arm of the study, and patients received the alternative test article. SPECT images were visually analysed and scored in a nine segment model by two blinded observers. In addition, circumferential profile analysis was conducted.

RESULTS

By visual interpretation 25 segments displayed redistribution of the ribose, but not in the saline study, 14 reversible segments were seen on the saline study alone and 18 were seen on both studies (P = ns). In six patients ribose identified a greater number of redistributing segments and in a further six patients saline identified more reversible segments. Comparison of mean values of defect extent severity and percentage reversibility scores generated from the circumferential profile analysis showed no significant difference between the two arms of the study.

CONCLUSION

A 5 min bolus injection of D-ribose following combined adenosine/dynamic exercise stress confers little benefit on the identification of redistribution of thallium-201. These results differ from those of previous studies which showed that a 30 min infusion of D-ribose following treadmill exercise significantly enhanced thallium redistribution. The duration of the ribose infusion is likely to be an important factor influencing the effect brought to bear on the redistribution of the tracer, and should be run over 30 min, or longer.

A eukaryotic translation initiation factor 2-associated 67 kDa glycoprotein partially reverses protein synthesis inhibition by activated double-stranded RNA-dependent protein kinase in intact cells

A eukaryotic translation initiation factor 2 (eIF-2)-associated 67 kDa glycoprotein (p67) protects the eIF-2 alpha-subunit from inhibitory phosphorylation by eIF-2 kinases, and this promotes protein synthesis in the presence of active eIF-2 alpha kinases in vitro [Ray, M. K., et al. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 539-543]. We have now examined the effect of overexpression of this cellular eIF-2 kinase inhibitor in an in vivo system using transiently transfected COS-l cells. In this system, coexpression of genes that inhibit PKR activity restores translation of plasmid-derived mRNA. We now report the following. (1) Transient transfection of COS-1 cells with a p67 expression vector increased p67 synthesis by 20-fold over endogenous levels in the isolated subpopulation of transfected cells. (2) Cotransfection of p67 cDNA increased translation of plasmid-derived mRNAs. (3) Overexpression of p67 reduced phosphorylation of coexpressed eIF-2 alpha. (4) p67 synthesis was inhibited by cotransfection with an eIF-2 alpha mutant S51D, a mutant that mimics phosphorylated eIF-2 alpha, indicating that p67 cannot bypass translational inhibition mediated by phosphorylation of the eIF-2 alpha-subunit. These results show that the cellular protein p67 can reverse PKR-mediated translational inhibition in intact cells.

First-rib exostosis bursa

We describe a case of exostosis bursa of the first left rib. Clinical features, investigations, and surgical management are described in detail.

Impaired thermoregulation in Raynaud's phenomenon

In an attempt to examine the role of the thermoregulatory apparatus in the etiology of Raynaud's phenomenon (RP), the authors exposed 15 women with RP and 12 controls to central body cooling and central body warming. Subjects were placed in an environmental chamber at 25 degrees C. Their right hand was placed in an annex of the chamber, which was insulated from the main chamber and maintained at a constant temperature of 25 degrees C throughout the experiment. Blood flow was measured in the digits of the right hand by venous occlusion strain gauge plethysmography and skin thermometry. Body temperature was measured with an oral thermometer. The temperature of the chamber was then increased to 35 degrees C and then reduced to 13 degrees C for twenty-five minutes with measurements repeated. Following this period patients were rewarmed in an ambient temperature of 35 degrees C for twenty minutes.

RESULTS

subjects with RP had significantly lower blood flow at all stages of the test; moreover, their digital rewarming response following central cooling was considerably prolonged when compared with controls. Body temperature was lower and dropped significantly more in the RP group following the cold challenge. The authors conclude that subjects with RP have an impaired thermoregulatory mechanism. This may partially explain cold sensitivity.