Henning Mothes

Efficacy of major general surgery performed by non-physician clinicians at a central hospital in Malawi

In some sub-Saharan African countries non-physician clinicians have to perform major general surgery without medical officers and surgeons. The safety of this practice has not been established. The aim of this study was to evaluate the contribution of clinical officers (COs) to major general surgery at Zomba Central Hospital. We performed a retrospective five-year period study during 2003–2007. The perioperative outcome for three procedures was analysed. During the study 2931 major general surgical procedures were performed: 1437 (49%) by surgeons; 366 (12.5%) by COs assisted by surgeons; and 1128 (38.5%) by COs alone. COs performed 50% of prostatectomies, ventriculo-peritoneal-shuntings and strangulated hernia repairs with bowel resection alone. Baseline parameters and perioperative outcomes of the patients who underwent operations with surgeons present (as operator or assistant, ‘surgeon group’) or patients operated by COs alone (‘CO group’) were similar. COs can safely perform major general surgery when adequate training and supervision are provided.

Defensin alpha 6 ( DEFA 6 ) overexpression threshold of over 60 fold can distinguish between adenoma and fully blown colon carcinoma in individual patients

BackgroundIt is known that alpha-defensin expression is enhanced in colon cancer. However, the expression of human alpha defensin 6 (DEFA 6) in earlier stages, such as adenoma, has so far not yet been studied in a patient resolved manner.MethodsBy using quantitative Real Time-PCR, the gene expression pattern of DEFA 1-3 and DEFA 6 was analyzed in tissue of different stages of carcinogenesis, derived from colorectal cancer patients. In addition to paired normal and tumor tissue, matched normal near tumor and adenoma tissue samples were examined.ResultsThe median gene expression of human defensin alpha 6 (DEFA 6) has been found to be moderately increased (~ 5 fold) in tumor samples derived from individuals with colorectal cancer (CRC) when compared to their normal counterparts. However, when the data were analyzed in a patient-wise manner, a large expression variation among individual patients is found, making the use of DEFA 6 for individual diagnosis of fully blown colon carcinoma difficult. Surprisingly, in adenoma the gene expression analysis revealed a 100 fold increased median expression of DEFA 6 relative to normal colon tissue. 13/18 samples had an individual overexpression of more than 60 fold in adenoma but only 3/17 in carcinoma. In each of the individual patients, at least either the adenoma or the carcinoma showed strong DEFA 6 overexpression.ConclusionsWe suggest that the expression of DEFA 6 preferably can be used as a potential diagnostic marker for adenoma and not as a marker for fully blown carcinoma. This is supported by the fact that DEFA 6 is a downstream target of the Wnt pathway, which is mutational active during the earliest stage of cancer development.

Butyrate suppresses mRNA increase of osteopontin and cyclooxygenase-2 in human colon tumor tissue

The short chain fatty acid (SCFA) butyrate, a product of fermentation of dietary fiber in the human colon, is found to exert multiple regulatory processes in colon carcinogenesis. The aim of this study was to find out whether butyrate affects the tumor-promoting genes osteopontin (OPN) and cyclooxygenase (COX)-2, their respective proteins and/or their functional activity in matched normal, adenoma and tumor colon tissues obtained from 20 individuals at colon cancer surgery. Quantitative real-time polymerase chain reaction experiments showed increased levels of OPN and COX-2 messenger RNA in tumor tissues when compared with the adjacent normal samples (P < 0.001). The addition of butyrate reduced OPN and COX-2 mRNA expression in all tissue types compared with the related medium controls (tumor: P < 0.05). In tumor samples, a downregulation of up to median 35% (COX-2) and 50% (OPN) was observed, respectively. Thereby, tumors with lower levels of OPN basal expression were more sensitive to inhibition and vice versa for COX-2 in normal tissue. At the protein and enzyme level, which were determined by using western blot and enzyme immunometric assays, the impact of the SCFA was not clearly visible anymore. The active proteins of OPN and COX-2 (determined by prostaglandin E(2)) were found to correlate with their respective mRNA expression only in 50-63% of analyzed donors. For the first time, our data reveal new insights into the chemoprotective potential of butyrate by showing the suppression of OPN and COX-2 mRNA in primary human colon tissue with the strongest effects observed in tumors.

Butyrate modulates antioxidant enzyme expression in malignant and non‐malignant human colon tissues

The induction of antioxidant enzymes is an important mechanism in colon cancer chemoprevention, but the response of human colon tissue to butyrate, a gut fermentation product derived from dietary fiber, remains largely unknown. Therefore, our study investigated the effect of a butyrate treatment on catalase (CAT) and superoxide dismutase (SOD2) in matched human colon tissues of different transformation stages (n = 3–15 in each group) ex vivo. By performing quantitative real‐time PCR, Western blot, and spectrophotometric measurements, we found an increase in SOD2 at expression and activity level in colonic adenocarcinomas (mRNA: 1.96‐fold; protein: 1.41‐fold, activity: 1.8‐fold; P < 0.05). No difference was detectable for CAT between normal, adenoma, and carcinoma colon tissues. Treatment of normal colon epithelium (12 h) with a physiologically relevant concentration of butyrate (10 mM) resulted in a significant increase (P < 0.05) in CAT mRNA (1.24‐fold) and protein (1.39‐fold), without affecting the enzymatic activity. Consequently, preliminary experiments failed to show any protective effect of butyrate against H2O2‐mediated DNA damage. Despite a significantly lowered SOD2 transcript (0.51‐fold, P < 0.01) and, to a lesser extent, protein level (0.86‐fold) after butyrate exposure of normal colon cells, the catalytic activity was significantly enhanced (1.19‐fold, P < 0.05), suggesting an increased protection against tissue superoxide radicals. In malignant tissues, greater variations in response to butyrate were observed. Furthermore, both enzymes showed an age‐dependent decrease in activity in normal colon epithelium (CAT: r = −0.49, P = 0.09; SOD2: r = −0.58, P = 0.049). In conclusion, butyrate exhibited potential antioxidant features ex vivo but cellular consequences need to be investigated more in depth.

Human Neutrophil Peptides 1-3 – Early markers in development of colorectal adenomas and carcinomas

Expression of Human Neutrophil Peptides (HNP) 1–3 was recently found to be associated with development of colorectal cancer. Raised defensin-expression in tumours is believed to stem from increased infiltration of neutrophils into tumour environment. To further specify the role of α-defensins in tumourigenesis and progression, HNP1–3 were analyzed in colorectal adenomas and carcinomas of 87 patients and quantified in relation to cancer stage and grading. Using the ProteinChip arrays, HNP1–3 were found upregulated in both colorectal adenomas and carcinomas. By combining the array with Laser capture microscopy we were able to confirm that HNP1–3 are expressed by tumour cells but not by neutrophils or other tumour invading cells. These findings suggest that α-defensins are more likely to contribute to tumour growth than they are to mount an effective host anti-tumour response. However, the amount of HNP-expression was not found to be related to tumour stage, grading, and serological tumour markers.

Do patients in rural Malawi benefit from upper gastrointestinal endoscopy

The aim of this study was to evaluate the benefits of upper gastrointestinal endoscopy at central hospital level in Malawi and to draw conclusions from its use in the treatment of patients presenting with dysphagia and dyspepsia to health institutions in rural Africa. This retrospective study was carried out in order to investigate the endoscopic findings in 455 patients who presented to Zomba Central Hospital, Malawi, with upper gastrointestinal symptoms. Fifty-six percent of patients presenting with dysphagia were found to have oesophageal carcinoma. In 50% of patients with epigastric pain and 44% with abdominal pain, an endoscopy did not reveal any pathological findings. The intended treatment was frequently altered as a result of performing the endoscopy. We were able to treat patients according to their specific diagnosis in a significantly higher number than before: 51% versus 18% of those presenting with dysphagia, 96% versus 24% of those with epigastric pain and 90% versus 39% of those with abdominal pain. Upper gastrointestinal endoscopy is a feasible diagnostic tool in developing countries which improves the detection and treatment of diseases of the gastrointestinal tract.

Chemopreventive potential of in vitro fermented nuts in LT97 colon adenoma and primary epithelial colon cells

Due to their beneficial nutritional profile the consumption of nuts contributes to a healthy diet and might reduce colon cancer risk. To get closer insights into potential mechanisms, the chemopreventive potential of different in vitro fermented nut varieties regarding the modulation of genes involved in detoxification (CAT, SOD2, GSTP1, GPx1) and cell cycle (p21, cyclin D2) as well as proliferation and apoptosis was examined in LT97 colon adenoma and primary epithelial colon cells. Fermentation supernatants (FS) of nuts significantly induced mRNA expression of CAT (up to 4.0‐fold), SOD2 (up to 2.5‐fold), and GSTP1 (up to 2.3‐fold), while GPx1 expression was significantly reduced by all nut FS (0.8 fold on average). Levels of p21 mRNA were significantly enhanced (up to 2.6‐fold), whereas all nut FS significantly decreased cyclin D2 expression (0.4‐fold on average). In primary epithelial cells, expression of CAT (up to 3.5‐fold), GSTP1 (up to 3.0‐fold), and GPx1 (up to 3.9‐fold) was increased, whereas p21 and cyclin D2 levels were not influenced. Nut FS significantly inhibited growth of LT97 cells and increased levels of early apoptotic cells (8.4% on average) and caspase 3 activity (4.6‐fold on average), whereas caspase 3 activity was not modulated in primary colon cells. The differential modulation of genes involved in detoxification and cell cycle together with an inhibition of proliferation and induction of apoptosis in adenoma cells might contribute to chemopreventive effects of nuts regarding colon cancer.

Systematic classification of uterine cervical elongation in patients with pelvic organ prolapse

OBJECTIVE To define and classify cervical elongation, to compare uterine measurements after prolapse hysterectomy with a non-prolapse control group, and to associate stage of prolapse and degree of cervical elongation. STUDY DESIGN This was a single-centre retrospective case-control study conducted at the University Hospital, Urogynaecological Unit, with a certified urogynaecological surgeon. Data were collected from patients with and without pelvic organ prolapse (POP) who underwent laparoscopically assisted vaginal hysterectomy. Post-hysterectomy uterine cervical elongation was examined using the corpus/cervix ratio (CCR), calculated from measurements taken on photographs. Cervical elongation was classified as physiological (grade 0, CCR>1.5) grade I (CCR>1 and ≤1.5) grade II (CCR>0.5 and ≤1), and grade III (CCR≤0.5). RESULTS Cervical elongation was detected in 288/295 (97.6%) patients in the prolapse group (grade I, 44/288 [15.2%]; grade II, 212 [73.6%]; grade III, 32 [11.1%]). Mean CCR was greater among those with stage II/III than among those with stage IV prolapse (1.0±0.4 vs. 0.8±0.2; p<0.001). Grades of cervical elongation and prolapse stages were associated (p<0.001). Grade I cervical elongation was detected in 26/69 (37.6%), grade II in 5/69, and grade III in 0/69 patients of the control group. Cervical elongation was found more often in the prolapse group compared to the control group (p<0.001). Mean total uterine length did not differ between the prolapse and control groups (8.0±1.6 vs. 8.2±1.3cm), but mean calculated cervical length was greater in the prolapse group than in the control group (4.4±1.1 vs. 3.1+0.8cm; p<0.001). CONCLUSIONS Uterine cervical elongation is found in patients undergoing hysterectomy for pelvic organ prolapse. Cervical elongation grades and prolapse stages are correlated. Defining uterine cervical elongation based on corpus/cervix ratio with grades I-III could be a valuable basic tool for further research.

Culturing explanted colon crypts highly improves viability of primary non-transformed human colon epithelial cells.

Chemoprotective effects of nutritional compounds are usually studied in cell lines. Studies using primary human colon cells have been limited due to the lack of established methods regarding their culture. We therefore optimized isolation and culture of non-transformed human epithelial cells from individual donors to enrich viable cells and sufficient amounts of intact RNA. Isolated epithelial cells were seeded in different coated cell culture dishes combined with several media (2-24h). To avoid cells from anoikis, also intact colon crypts were isolated to maintain cell interactions. These crypts were incubated with gut fermentation products (24h) derived from indigestible carbohydrates. In none of the coated (fibronectin, laminin) cell culture dishes isolated epithelial cells did attach. The number of these cells remaining in suspension, decreased already after 2h to 20%. Intact colon crypts cultured as pellets showed a stable viability up to 24h (91±4%) and were suitable to gain a sufficient quantity of RNA. The use of colon crypts with an appropriate cell culture medium could double the lifespan of intestinal epithelial cells from 12 up to 24h and represents a promising approach to study early events in carcinogenesis and chemoprevention as well as other diseases of the colon.

Detection of HPV16 in Esophageal Cancer in a High-Incidence Region of Malawi

This study was designed to explore the role of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC). Fifty-five patients receiving diagnostic upper gastrointestinal endoscopy at Zomba Central Hospital or Queen Elizabeth Hospital in Blantyre (Malawi) in 2010, were included in our study. Formalin-fixed paraffin-embedded biopsies were collected for histopathological diagnosis. HPV DNA was detected using multiplex Quantitative PCR (qPCR) and in situ hybridization (ISH). p16INK4a staining served as a surrogate marker for HPV oncogene activity. Cell proliferation was determined by Ki-67 staining. Human immunodeficiency virus (HIV) status was evaluated by serology. Data on the consumption of alcohol and tobacco, and history of tuberculosis (TBC), oral thrush, and Herpes zoster, were obtained by questionnaire. Forty patients displayed ESCC, three displayed dysplastic epithelium, and 12 displayed normal epithelium. HPV16 was detected in six ESCC specimens and in one dysplastic lesion. Among HPV-positive patients, viral load varied from 0.001 to 2.5 copies per tumor cell. HPV DNA presence could not be confirmed by ISH. p16INK4a positivity correlated with the presence of HPV DNA (p = 0.03). Of particular note is that the Ki-67 proliferation index, in areas with diffuse nuclear or cytoplasmatic p16INK4a staining ≥50%, was significantly higher in HPV-positive tumors compared to the corresponding p16INK4a stained areas of HPV-negative tumors (p = 0.004). HPV infection in ESCC was not associated with the consumption of tobacco or alcohol, but there were significantly more patients drinking locally brewed alcohol among HPV-positive tumor patients compared to non-tumor patients (p = 0.02) and compared to HPV-negative tumor patients (p = 0.047). There was no association between HIV infection, history of TBC, Herpes zoster, oral thrush, or HPV infection, in ESCC patients. Our indirect evidence for viral oncogene activity is restricted to single tumor cell areas, indicative of the role of HPV16 in the development of ESCC. The inhomogeneous presence of the virus within the tumor is reminiscent of the “hit and run” mechanism discussed for β-HPV types, such as HPV38.