Structural and functional abnormalities in lungs in patients with achalasia

Dilatation and oesophageal body aperistalsis in achalasia can lead to stasis which in turn can induce repeated microaspiration. It is therefore conceivable that patients with achalasia may also have abnormalities in lungs secondary to repeated episodes of microaspiration. There is a lack of systematic study on involvement of lungs in patients with achalasia. Thirty patients with achalasia underwent pulmonary function tests (spirometry, and carbon mono-oxide diffusion capacity) and high resolution computerized tomography (HRCT) of the chest. The mean age of patients and mean duration of disease were 33.5 +/- 10.9 years and 28.1 +/- 27.3 months respectively. Regurgitation was present in 22 (73.3%) of them. Respiratory symptoms in them were dry cough in 17 (56.6%), and chest pain in 18 (60%). The oesophagus was dilated in 26 (86.6%) and 13 (43.3%) had residue in oesophagus. Sixteen (53.3%) patients had either anatomical changes as seen on HRCT or functional changes as observed on pulmonary function tests. Of those with functional abnormalities, five (16.6%) and one (3.3%) had restrictive and obstructive airways disease respectively. While evidence of tracheo-bronchial compression by dilated oesophagus was present in eight (26.6%), 10 (33.3%) patients had parenchymal lung disease [nodular opacities in five (16.6%), ground glass appearance six (20%), patchy pulmonary fibrosis five (16.6%), air trapping two (6.6%), consolidation and bronchiectasis one (3.3%) each]. There was a significant association between presence of regurgitation and dilatation of oesophagus (P = 0.032). More than half (53.3%) of patients with achalasia have structural and/or functional abnormalities in lungs.

Klebsiella meningitis. A case report

Acute bacterial meningitis is a severe CNS infection occurring mostly in infants and older children. Bacterial meningitis caused by gram-negative bacteria is usually fatal. Klebsiella pneumoniae is an uncommon gram-negative bacteria causing meningitis with a poor outcome. Though the commonest presentation of bacterial meningitis is fever, patients usually seek medical attention for uncontrolled seizure and features of raised ICP. The commonest complications of gram-negative bacterial meningitis including Klebsiella meningitis are subdural hygroma / empyema, hydrocephalus, infarcts (both arterial and venous) and cortical blindness due to hypoxic ischaemic insult. MRI is the best modality for evaluating these patients for early diagnosis. Early institution of treatment significantly reduces the mortality and morbidity. We describe a case of acute bacterial meningitis caused by Klebsiella pneumoniae with MR evidence of sinus thrombosis, venous infarcts and subdural hygroma.

Chronic Tuberculous Retropharyngeal Abscess Due to Vertebral Tuberculosis with Associated Calvarial Tuberculosis

The occurrence of chronic tuberculous retropharyngeal abscess and calvarial tuberculosis is rare, even in isolated form. Chronic tuberculous retropharyngeal abscess is usually due to vertebral tuberculosis in adults. Calvarial tuberculosis is a rare manifestation of extra-pulmonary tuberculosis with limited reports in medical literature. We describe a rare case of chronic tuberculous retropharyngeal abscess due to vertebral tuberculosis with associated calvarial tuberculosis.

The autoantibody rheumatoid factor may be an independent risk factor for ischaemic heart disease in men

BACKGROUND

Subjects with rheumatoid arthritis have an increased prevalence of ischaemic heart disease (IHD). This is most likely in those people with the autoantibody rheumatoid factor (RF). RF is strongly associated with rheumatoid arthritis (RA) but is also present in up to 15% of all adults.

OBJECTIVE

To determine whether RF might identify people in a general population who also share an increased likelihood of developing IHD.

METHODS

Subjects from the Hertfordshire Cohort Study were investigated for the presence of RF. Subjects completed a questionnaire and attended a clinic where a history of IHD was recorded (ECG, coronary artery bypass grafting, Rose chest pain). Associations between the presence of RF, antinuclear antibodies (ANA), anticardiolipin antibodies (ACA) and IHD in 567 men and 589 women were investigated and compared with traditional risk factors for IHD.

RESULTS

RF was associated with an increased likelihood of IHD in men (odds ratio (OR) = 3.1, 95% CI 1.7 to 5.4, p<0.001). This increased risk could not be explained by traditional risk factors for IHD (mutually adjusted OR for RF 2.9 (95% CI 1.6 to 5.3), p<0.001). There was no significant association between RF in women or between ANA or ACA with IHD in men or women.

CONCLUSION

This work suggests that RF is an independent risk factor for IHD in the general population. It lends support to the importance of inflammation in atherosclerosis and suggests that autoimmune processes may be involved. In addition, it raises the intriguing possibility that RF may have a direct role in the pathogenesis of IHD in some subjects.

Pyomyositis: a diagnostic problem

A case of a 45-year-old lady presenting with symptoms suggestive of pancreatitis is described. Initially the findings on Imaging were ambiguous while the enzyme studies were against the diagnosis of pancreatitis. Recurrence of symptoms and with Increased intensity prompted repeated imaging and further investigations. Finally, by a combination of CT scan, MR imaging and muscle biopsy the rare diagnosis of pyomyositis was established. The fact that this case was difficult to diagnose because of its rarity and its mimicking pencreatitis is discussed.

Growth and infectious exposure during infancy and the risk of rheumatoid factor in adult life

BACKGROUND

The contribution of the environment to rheumatoid arthritis (RA) remains uncertain. Intrauterine and early postnatal life may be important. Rheumatoid factor (RF) found in around 10% of the normal population confers a risk of developing RA and may be present years before onset of clinical disease. The immune pathology leading to RA and RF may have similar genetic and environmental influences.

OBJECTIVE

To measure RF in people for whom data on birth weight, infant growth, and markers of infectious exposure during infancy and childhood, had been previously recorded.

METHODS

675 men and 668 women aged 59-67 years, born and still resident in Hertfordshire, UK, were studied. RF was measured with an ELISA. Associations between presence of RF, early growth, and markers of hygiene in infancy, were investigated.

RESULTS

RF was detected in 112/675 (16.6%) men and 79/668 (11.8%) women. No significant relationships existed between early growth and presence of RF in men or women. Among women, sharing a bedroom during childhood was associated with a lower risk of RF positivity (OR = 0.48, 95% CI 0.30 to 0.78, p = 0.003).

CONCLUSIONS

A developing immune system exposed to increased infectious exposure is less likely to produce RF in adult life; this may reduce the pathological process which leads to RA.

A case of disseminated hydatidosis

A young lady initially found to have hydatid cysts in the lung only, subsequently within a very short period was found to develop cysts in the liver. Soon after, she developed cysts in the subcutaneous tissue over the anterolateral chest wall, which, on investigation, revealed hepatic cysts herniating through the chest wall defects caused by previous operations. The unique features of this case include the degree of dissemination, the multiplicity of sites and the peculiar nature of herniation of the hepatic cysts into the parietes.

Mitotically active haemorrhagic cellular (apoplectic) leiomyoma

Apoplectic leiomyoma is a distinctive smooth muscle tumour usually occurring in women either taking oral contraceptives or who are pregnant or recently postpartum. Most of these tumours show 0-2 mitoses per 10 high power fields, but a mitotic index of up to 8 per 10 high power fields is allowed in such tumours. We describe an apoplectic leiomyoma with a number of atypical features including a high mitotic index (up to 20 per 10 high power fields) in a 47-year-old woman. Follow-up clinically and by computerised tomography (CT) for 3 years demonstrates no recurrence.

Heat shock inhibits radiation-induced activation of NF-kappaB via inhibition of I-kappaB kinase

Radiation stimulates signaling cascades that result in the activation of several transcription factors that are believed to play a central role in protective response(s) to ionizing radiation (IR). It is also well established that heat shock alters the regulation of signaling cascades and transcription factors and is a potent radiosensitizing agent. To explore the hypothesis that heat disrupts or alters the regulation of signaling factors activated by IR, the effect of heat shock on IR-induced activation of NF-kappaB was determined. Irradiated HeLa cells demonstrated transient increases in NF-kappaB DNA binding activity and NF-kappaB protein nuclear localization. In addition, irradiated cells demonstrated increased I-kappaB phosphorylation and decreased I-kappaBalpha cytoplasmic protein levels, corresponding temporally with the increase of NF-kappaB DNA binding. Heat shock prior to IR inhibited the increase in NF-kappaB DNA binding activity, nuclear localization of NF-kappaB, and the phosphorylation and subsequent degradation of I-kappaB. I-kappaB kinase (IKK) immunoprecipitation assays demonstrated an increase in IKK catalytic activity in response to IR that was inhibited by pretreatment with heat. Kinetic experiments determined that heat-induced inhibition of NF-kappaB activation in response to IR decayed within 5 h after heating. Furthermore, pretreatment with cycloheximide, to block de novo protein synthesis, did not alter heat shock inhibition of IR induction of NF-kappaB. These experiments demonstrate that heat shock transiently inhibits IR induction of NF-kappaB DNA binding activity by preventing IKK activation and suggests a mechanism independent of protein synthesis.

Intron sequences and the length of the downstream second exon affect the binding of hnRNP C proteins in an in vitro splicing reaction

The proteins that are in direct contact with the pre-mRNA in an in vitro splicing reaction were analyzed by UV cross-linking experiments. Six major proteins (120, 55, 44, 42, 39 and 38 KD) and three minor polypeptides (84, 72 and 63 KD) were detected. The predominant proteins 44, 42 KD belong to the class of hnRNP C proteins since they were immunoprecipitated by monoclonal antibodies directed against hnRNP C proteins. The cross-linked proteins were not detected in the absence of Mg2+, ATP or when RNA lacking introns were used as substrates in the splicing reactions. The effect of exon sequences on the binding efficiency for the photocrosslinked proteins was investigated. Transcripts containing a second exon of 24 nucleotides for the beta-globin or 107 nucleotides for the mouse insulin, yielded a reduced amount of cross-linked proteins when compared with "full length" pre-mRNAs. Sequences within the first exon of the beta-globin pre-mRNA did not affect the binding efficiency of these proteins. The reduced binding efficiency of the cross-linked proteins for the truncated beta-globin or mouse insulin pre-mRNAs correlated with the lower efficiency for in vitro splicing. Substitutions with unrelated sequences in the beta-globin second exon restore the binding of the cross-linked proteins indicating that the length of the second exon and not specific sequences are relevant for the binding efficiency of these proteins. The SP6/mouse insulin oligonucleotides cross-linked to the hnRNP C proteins were isolated and sequenced. A 17-mer was located in the second exon (134 nucleotides downstream from the 3' splice site) and a 14-mer in the intron region (25 nucleotides downstream the 5' splice site). The beta-globin oligonucleotides cross-linked to the hnRNP C proteins were a 13-mer in the second exon (28 nucleotides downstream the 3' splice site) and an 8-mer in the first exon (81 nucleotides downstream the 5' end of the pre-mRNA). Our results indicate that the hnRNP C proteins interact with those oligonucleotides located in different regions of the pre-mRNA. The binding efficiency of those proteins, however, depends on the length of the second exon and the presence of intron sequences (secondary and/or tertiary pre-mRNA structure).

The secondary structure of a messenger RNA precursor probed with psoralen is melted in an in vitro splicing reaction

The secondary structure of the SP6/mouse insulin precursor RNA was determined by psoralen cross-linking experiments. A series of long-range contacts occur within the left half of the pre-mRNA that contains the intervening sequence. Multiple secondary structures for the pre-mRNA exist since some of the interactions share common sites. In splicing buffer but without the splicing extract added, many of these interactions are stable up to at least 50 degrees C. These interactions, however, are dissociated during the in vitro splicing reaction. This dissociation requires ATP and it occurs during the first 30 min. of the splicing reaction. Pre-mRNAs containing psoralen cross-links in different locations within the RNA molecule were purified and used as substrates for in vitro splicing. Psoralen cross-links at any of the double-stranded regions resulted in complete inhibition of the splicing reaction. This indicates that destabilization of the secondary structure of the SP6/mouse insulin pre-mRNA is necessary for in vitro splicing.